Search PubMed⌕ Search

Biomedical subjects

T Araki

Publications and source records attributed to T Araki.

At least 91 records · Page 5Linked to original sources
PubMed2001

Fusion of a sequence from HEI10 (14q11) to the HMGIC gene at 12q15 in a uterine leiomyoma.

Uterine leiomyoma, a benign smooth-muscle tumor of the myometrium, is the most commonly encountered neoplasm in women of reproductive age. Band q15 of chromosome 12 is often rearranged in benign mesenchymal tumors such as uterine leiomyomas, and the HMGIC gene, encoding a protein of the high-mobility-group (HMG), is present in that region. Using 3' rapid amplification of cDNA ends (3'RACE) experiments, we isolated an ectopic sequence that was fused to HMGIC in a uterine leiomyoma. Cloning of the fusion cDNA identified a gene termed rising dbl quote, left (low)homo sapiens enhancer of invasion 10" (HEI10) as the fusion partner. Radiation hybrid mapping revealed that the normal location of HEI10 is at 14q11. In the fusion transcript the first two exons of the HMGIC gene, which encode DNA-binding domains, were fused to the 3' portion of the HEI10 gene. This rearrangement implicates HMGIC in the tumorigenesis of uterine leiomyoma, and suggests that its fusion HMGIC product may play a role in mesenchymal differentiation.

Amino Acid Sequence↗
PubMed2001

Duct-penetrating sign at MRCP: usefulness for differentiating inflammatory pancreatic mass from pancreatic carcinomas.

PURPOSE: To define the duct-penetrating sign at magnetic resonance (MR) cholangiopancreatography (MRCP) and to assess the usefulness of this sign for distinguishing an inflammatory pancreatic mass (IPM) from a conventional pancreatic carcinoma (CPC) compared with arterial phase computed tomography (hereafter, CT) and arterial phase MR imaging (hereafter, MR imaging). MATERIALS AND METHODS: MRCP, CT, and MR images were compared by means of receiver operating characteristic (ROC) analysis for 11 IPMs and 43 CPCs. With the MRCP images, a morphologic classification of the main pancreatic duct (MPD) was attempted for all lesions. On the basis of this classification and the enhancement patterns of a lesion, all readers graded the presence of IPM or CPC on a five-point scale for all images. RESULTS: On the MRCP images, the morphologic characteristics of the MPD were nonobstruction for IPM (28 of 33, 85%) and obstruction or irregular stenosis for CPC (124 of 129, 96%). At ROC analysis among all the techniques, MRCP images had the highest value (0.98) for significant areas under the ROC curve (CT, 0.84; MR, 0.76) (P <.001). For the duct-penetrating sign in the broad sense (nonobstructed MPD) and the sign in the narrow sense (only normal MPD), the sensitivity, specificity, and accuracy for diagnosis of IPM were 85%, 96%, and 94%, respectively, and 36%, 100%, and 87%, respectively. CONCLUSION: The duct-penetrating sign on MRCP images was more helpful to distinguish IPM from CPC than were the enhancement patterns on CT and MR images.

Aged↗
PubMed2001

Regulation of platelet aggregation in vitro by plasma adenosine in preeclampsia.

The aim of this study was to evaluate the possible role of plasma adenosine in platelet aggregation in preeclampsia. We measured the plasma adenosine concentration [ADO] and in vitro platelet aggregation in the third trimester of normal pregnant (n = 15) and preeclamptic women (n = 15). The mean plasma [ADO] in preeclampsia was 0.68 +/- 0.08 microM (means +/- SEM), significantly higher than in normal pregnancy (0.42 +/- 0.09 microM) (p < 0.05). In preeclampsia, platelet aggregation in response to collagen was approximately 40% lower than that in normal pregnancy (p < 0.05). There was an inverse correlation between the plasma [ADO] and platelet aggregation in vitro (r = -0.27, p < 0.05). These results suggest reduced platelet aggregation in preeclampsia may be at least in part attributed to an elevation of the the plasma [ADO].

Adenosine↗
PubMed2001

Fetal circulatory responses to maternal blood loss.

We examined the fetal circulatory responses to maternal blood loss in pregnant women during the third trimester. Seven healthy women with placenta previa and singleton pregnancies underwent phlebotomies in an autologous donation program. Four hundred milliliters of blood was collected within 15 min at 34 and 35 weeks of gestation. Continuous electric recordings of fetal heart rate were performed during the first blood collection, and the maternal uterine artery (UtA), umbilical artery (UmA) and fetal middle cerebral artery (MCA) Doppler velocity waveforms were recorded before, immediately after and 24 h after the second collection in each patient. The average fetal heart rate, maternal UtA and UmA pulsatility indices did not change measurably during or after maternal blood collections. However, the average fetal MCA pulsatility index decreased significantly 24 h after maternal blood loss. The observation of a decrease in fetal MCA pulsatility index may indicate delayed fetal asphyxia following mild maternal hemorrhage.

Adult↗
PubMed2001

Relation between serum uric acid and plasma adenosine levels in women with preeclampsia.

The aim of this study was to examine the relationship between plasma adenosine and serum uric acid levels in women with preeclampsia. Maternal arterial blood sampling was performed to measure serum uric acid and plasma adenosine levels in 20 pregnant women complicated by preeclampsia and 22 normal pregnant women at 33-38 weeks of gestation. The average plasma adenosine levels were 0.31 +/- 0.12 micromol/l in the normal pregnant group and 0.45 +/- 0.11 micromol/l in the preeclampsia group. The mean serum uric acid level in women with preeclampsia was 5.9 +/- 0.60 mg/dl, significantly higher than in the normal pregnant women (4.4 +/- 0.69 mg/dl). Positive correlations were found between serum uric acid and plasma adenosine levels in both the group with (r(2) = 0.38, p < 0.05) and the group without (r(2) = 0.54, p < 0.05) preeclampsia. There was also a significant correlation between serum uric acid and plasma adenosine levels on the whole (r(2) = 0.59, p < 0.05). Our results suggest that increased adenosine is a contributing source of preeclamptic hyperuricemia.

Adenosine↗
PubMed2001

Correlation between grade III placenta and plasma antithrombin III activity in full term pregnancy.

We evaluated whether the presence of a grade III placenta correlates with blood hypercoagulability in pregnancy between 37 and 39 weeks of gestation. The placenta was graded by ultrasound in 155 healthy full-term women and the plasma levels of antithrombin III (AT III) activity, thrombin-antithrombin complex (TAT) and D-dimer were correlated with each placental grade. AT III activity levels tended to decrease with advancing placental grade from I to III (p < 0.05). D-dimer showed the same tendency while TAT did not. The incidence of reduced AT III activity levels (<70%) in women with a grade III placenta was about twice those in women with a grade II or I placenta, and that of AT III <80% was 3-fold greater. We concluded that the presence of a grade III placenta in full-term pregnancies correlates with blood hypercoagulability.

Adult↗
PubMed2001

Relation between plasma endothelin 1 levels and T helper 1: T helper 2 cell immunity in women with preeclampsia.

The aim of this study was to investigate the relationship between plasma endothelin 1 (ET-1) levels and T helper (Th)-1:Th2 cell immunity in women with preeclampsia. The percentage of Th1 and Th2 cells and the Th1:Th2 cell ratios in peripheral blood from 11 normal pregnant women and 11 patients with preeclampsia at 29-34 weeks of gestation were calculated using flow cytometry. The plasma ET-1 level was also determined using a modified radioimmunoassay. The plasma ET-1 concentrations and the Th1:Th2 cell ratios in normal pregnancies were significantly lower than those in patients with preeclampsia. Negative correlations were found between plasma ET-1 levels and Th2 cells in both the preeclamptic pregnancy groups and in the normal pregnant women. Our results indicate that elevated ET-1 levels are associated with a Th1:Th2 imbalance in preeclampsia.

Adult↗
PubMed2001

Applications of fluorescence microscopy to studies of dental hard tissue.

In this review we describe applications of fluorescence microscopy to investigations of dental hard tissue. Many studies have shown that human teeth show autofluorescence and several applications of fluorescence microscopy have been reported, although the chemical nature of autofluorescence remains unknown. However, most applications are based on a static measurement mode, which has inherent limitations. These limitations can be overcome by the use of time-resolved fluorescence microscopy. Therefore, we attempted to combine ordinary and time-resolved fluorescence microscopy to study human dentine. Using stationary measurements, blue fluorescence with a peak of 440 +/- 10 nm and a width of approximately 100 nm was observed. Increases in fluorescence intensity were found to be dependent upon age and temperature, regardless of tooth type or gender. The results suggest that the aging mechanism for crown dentine differs from that for root dentine and that the observed increase in fluorescence intensity is partially due to a temperature-dependent physicochemical mechanism. We speculate that fluorescence microscopy will become a useful tool for analysis of dental hard tissue in several fields.

Aging↗
PubMed2001

The mechanism of reaction of ebselen with superoxide in aprotic solvents as examined by cyclic voltammetry and ESR.

The mechanism of the redox reaction of ebselen with superoxide was investigated using both ESR and electrochemical techniques. The reaction with superoxide in aprotic solvents was followed by means of cyclic voltammetry and ESR spin-trapping. A decrease in the oxidation current due to superoxide as a result of the addition of ebselen was clearly observed in the cyclic voltammograms. Ebselen reduced the ESR signal intensity of 5,5-dimethyl-1-pyrroline N-oxide (DMPO)-superoxide in a dose-dependent manner. The formation of an amidyl radical in this redox reaction was confirmed by rapid mixing continuous-flow ESR. The selenonate form and the seleninate form of ebselen were identified as the final products of the reaction of ebselen with superoxide. The following mechanism for this redox reaction can be proposed: First, ebselen reacts with superoxide and is converted to an ebselen anion radical; second, the ebselen anion radical reacts with superoxide and is converted to the amidyl radical. Hydrogen abstraction by the amidyl radical occurs and gives both a seleninate form and a selenonate form.

Antioxidants↗
PubMed2001

Antioxidative properties of probucol estimated by the reactivity with superoxide and by electrochemical oxidation.

The reaction of probucol with superoxide (O2(*-)) was investigated in acetonitrile using both electron spin resonance (ESR) and electrochemical techniques. The formation of phenoxyl radical was observed during the reaction of probucol with O2(*-) by ESR spectroscopy. The reaction of probucol with O2(*-) in acetonitrile was followed by cyclic voltammetry. With the addition of probucol, the oxidation peak current of O2(*-) decreased concentration dependently. This suggests that probucol reacts with O2(*-), that is, probucol scavenges O2(*-) in acetonitrile. 2,6-Di-tert-butyl-p-benzoquinone was identified as the major product of the reaction of probucol with O2(*-) in acetonitrile. Electrochemical oxidation of probucol was also performed. Probucol gives an irreversible oxidation peak at ca. +1.4 V vs. the saturated calomel electrode in the cyclic voltammogram. Controlled-potential electrolysis was carried out at +1.2 V in a divided cell. 2,6-Di-tert-butyl-p-benzoquinone, 4,4'-dithiobis(2,6-di-tert-butylphenol), and 4,4'-trithiobis(2,6-di-tert-butylphenol) were identified as the products of anodic oxidation. These redox properties of probucol may correlate with the physiological activities.

Antioxidants↗
PubMed2001

Binding of a highly de-N-acetylated chitosan to Japanese pheasan lysozyme as measured by 1H-NMR spectroscopy.

Binding of a highly de-N-acetylated chitosan to Japanese pheasant lysozyme (JPL), which differs from hen egg white lysozyme (HEWL) by nine amino acid substitutions (including Arg114-->His), was investigated by 1H-NMR spectroscopy. The profile of the one-dimensional spectrum of JPL is essentially identical to that of HEWL. Using two-dimensional spectra of JPL and HEWL, several aromatic and aliphatic proton resonances of JPL were assigned by comparison. When a highly de-N-acetylated chitosan (number-average degree of polymerization, about 18; degree of acetylation, 0.04), where the N-acetylated units are predominantly surrounded by de-N-acetylated units (a monoacetylated chitosan), was added to the JPL solution, the NMR signals were clearly affected in Trp28 C5H and Ile98 gammaCH, as in the case of binding to HEWL. The dissociation constant of the monoacetylated chitosan evaluated from the NMR signal responses was calculated to be 0.23+/-0.05 mm (-31.5 kJ/mol), which is similar to that of HEWL (0.11+/-0.02 mm, -33.3 kJ/mol). Thus, the Arg-->His substitution of the 114th amino acid, which participates in sugar residue binding at the right-sided subsite F, did not significantly affect the chitosan binding. In addition, the C2H signal of His114 of JPL was not affected by the chitosan binding. These results suggest that the monoacetylated chitosan binds to subsites E and F through the left-sided binding mode.

Algorithms↗
PubMed2001

Purification and characterization of goose type lysozyme from cassowary (Casuarius casuarius) egg white.

A novel goose-type lysozyme was purified from egg white of cassowary bird (Casuarius casuarius). The purification step was composed of two fractionation steps: pH treatment steps followed by a cation exchange column chromatography. The molecular mass of the purified enzyme was estimated to be 20.8 kDa by SDS-PAGE. This enzyme was composed of 186 amino acid residues and showed similar amino acid composition to reported goose-type lysozymes. The N-terminal amino acid sequencing from transblotted protein found that this protein had no N-terminal. This enzyme showed either lytic or chitinase activities and had some different properties from those reported for goose lysozyme. The optimum pH and temperature on lytic activity of this lysozyme were pH 5 and 30 degrees C at ionic strength of 0.1, respectively. This lysozyme was stable up to 30 degrees C for lytic activity and the activity was completely abolished at 80 degrees C. The chitinase activity against glycol chitin showed dual optimum pH around 4.5 and 11. The optimum temperature for chitinase activity was at 50 degrees C and the enzyme was stable up to 40 degrees C.

Animals↗
PubMed2001

Two distinct populations of neurons expressing nitric oxide synthase mRNA in the female rat preoptic area: site specific changes induced by sex steroids.

Non-isotopic in situ hybridization histochemistry in the basal forebrain of gonadectomized juvenile female rats visualized neuronal nitric oxide synthase (nNOS) mRNA in two distinct cellular populations, one in the organum vasculosum of the lamina terminals (OVLT) and the other in the rostral preoptic area at the level of the anteroventral periventricular nucleus (rPOA). In the rPOA, digoxigenin-labeled nNOS mRNA positive cells were in close proximity to the cell body of gonadotropin-releasing hormone (GnRH) -immunoreactive neurons. In the OVLT, the labeled cells were in an area rich in GnRH fibers. In the frontal section of the rPOA, the labeled cells were distributed in an inverted V-shaped area over the third ventricle. Combined treatment with estradiol and progesterone caused a significant reduction in the number of nNOS mRNA positive cells in the inverted V-shaped area in the female rat rPOA. The treatment induced a luteinizing hormone surge at the time of sacrifice. In the OVLT, ovarian steroids had no effect on nNOS mRNA expression. The results indicate that nNOS mRNA expression in the rPOA is regulated by ovarian steroids in a site-specific manner.

Animals↗
PubMed2001

Massive subchorionic hematoma (Breus' mole) complicated by intrauterine growth retardation.

We present here a case of massive subchorionic hematoma complicated by intrauterine growth retardation and oligohydramnios diagnosed at 22 weeks' gestation. The patient was managed with the following medications: (1) tocolysis with ritodrine infusion, (2) 10%maltose infusion therapy (1500mL/day), (3) antibiotic infusion (cefotaxim sodium, 2 g/dayx7) and (4) kampo therapy with Sairei-to until delivery. At 33 weeks and 0 days' gestation, a female baby weighing 1,342 g was delivered without complication by caesarean section. During surgery, an escape of about 500~600 g of dark brown blood with no clots was noted from the subchorionic space of the placenta. Examination of the placenta showed a large fibrosis with well-defined margins on the fetal surface.

Adult↗
PubMed2001

Three-dimensional transfer functions of coherent anti-Stokes Raman scattering microscopy.

The three-dimensional coherent transfer function of confocal coherent anti-Stokes Raman scattering microscopy was derived theoretically. The three-dimensional optical transfer function was also derived under the weak-contrast assumption. The effect of a pinhole in front of the detector on the optical transfer function was estimated, and it was found that the cutoff frequency of the optical transfer function is independent of the pinhole. Micrometer-order spatial resolution along the optical axis was also experimentally demonstrated.

Microscopy, Confocal↗
PubMed2001

Visual demonstration of calcium accumulation in human arteries of upper and lower limbs.

To elucidate the calcium content of the arteries in the upper and lower limbs, the authors determined the calcium content of all the arteries in the upper and lower limbs continuously by microwave-induced plasma-atomic emission spectrometry. The subjects were an 87-yr-old man and a 72-yr-old woman. The calcium content was determined both in the arteries of the upper limbs continuously, such as the subclavian arteries and its distal arteries, and in the arteries of the lower limbs, such as the common iliac arteries and its distal arteries. The common finding that the higher accumulation of calcium occurred in the arteries of the lower limbs in comparison to the arteries of the upper limbs and extremely high accumulation of calcium occurred in the common, external, and internal iliac arteries was obtained in the two subjects. The calcium content of the arteries in the upper and lower limbs was visually demonstrated.

Aged↗