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T Ueda

Publications and source records attributed to T Ueda.

At least 667 records · Page 37Linked to original sources
PubMed1995

Surfactant treatment and ventilation effects on surfactant SP-A, SP-B, and SP-C mRNA levels in preterm lamb lungs.

The effects of exogenous surfactant treatment combined with postnatal ventilation on surfactant protein (SP)-A, SP-B, and SP-C steady-state mRNA levels were evaluated in preterm sheep at 120, 132, and 139 days gestation. Three groups were studied at each gestation period: animals ventilated and treated with 100 mg/kg natural sheep surfactant, animals ventilated and not treated with surfactant, and a comparison group of lambs that were neither ventilated nor treated with surfactant. In unventilated lambs, SP-A and SP-C mRNA levels measured by densitometry from Northern blots increased between 120 and 132 days gestation (P < 0.05). At 120 days gestation, no differences in SP-A, SP-B, or SP-C mRNA levels were noted among the three groups. At 132 days gestation, SP-A mRNA levels increased in both ventilated groups (P < 0.01), but no additional surfactant effect on SP-A mRNA expression was detected. There were no changes in SP-B or SP-C mRNA levels among the groups at 132 days gestation. At 139 days gestation, mRNA levels for both SP-A and SP-B increased after ventilation, compared with the unventilated groups (P < 0.05). Furthermore, an additional effect of surfactant treatment to increase SP-A mRNA levels relative to animals undergoing ventilation alone was noted (P < 0.05). We conclude that postnatal changes in mRNA levels for the surfactant proteins are gestationally regulated and protein specific.

Animals↗
PubMed1995

Exogenous surfactant function in very preterm lambs with and without fetal corticosteroid treatment.

We have asked whether the function of a bovine source surfactant frequently used clinically (Survanta) could be enhanced after exposure to the very preterm lung when the surfactant was subsequently tested in vivo in preterm surfactant-deficient rabbits. We also evaluated whether there would be effects resulting from fetal treatment with 0.5 mg/kg betamethasone given 48 h before delivery of lambs at 121 days gestational age. The fetal corticosteroid treatment significantly improved gas exchange, increased compliance, increased functional residual capacity, decreased vascular-to-alveolar protein leak, and increased static lung volumes. However, surfactant from both groups of lambs, recovered by alveolar wash and subsequently fractionated to recover the large-aggregate functional surfactant, was equivalent in function to the Survants given to the lambs when tested in preterm surfactant-deficient rabbits. Addition of plasma to Survanta resulted in high minimum surface tensions in vitro, and this inhibition could be prevented by supplementation of the Survanta with 5 or 10% sheep surfactant. No activation occurred with treatment of the very preterm lung, a result consistent with the lung being too immature to contribute components to the surfactant used for treatment. Fetal corticosteroid treatment had no effect on surfactant function at this gestational age.

Adrenal Cortex Hormones↗
PubMed1995

Effects of fetal corticosteroid treatments on postnatal surfactant function in preterm lambs.

Effects of prenatal corticosteroid on the properties of surfactant have not previously been evaluated. A single ultrasound-guided fetal injection with 0.5 mg/kg betamethasone 48 h before delivery of preterm lambs at 134- to 135-days gestation improved oxygenation, lowered the ventilatory pressures required to maintain arterial PCO2 between 30 and 40 Torr and decreased the protein leak of albumin from the intravascular to the alveolar space. This dose of glucocorticoid did not alter surfactant-saturated phosphatidylcholine pool sizes in the airspaces of preterm lambs. However, the treatment changed the characteristics of the surfactant recovered from the ventilated preterm lambs. The in vitro conversion from heavy to light subtype surfactant decreased from 59% for the saline-treated lambs to 37% for the corticosteroid-treated lambs after 180 min of surface area cycling (P < 0.02). Surfactant from the corticosteroid-treated lambs also increased the dynamic compliance of preterm surfactant-deficient rabbits more than did surfactant from the saline-treated lambs (P < 0.05). Prenatal treatment of preterm lambs with betamethasone improved the functional characteristics of surfactant without significant effects on the alveolar surfactant pool sizes.

Animals↗
PubMed1995

Comparative mapping of the imprinted U2afbpL gene on mouse chromosome 11 and human chromosome 5.

The genetic map location of the recently discovered imprinted gene U2afbpL has been verified and refined in several mouse crosses. RI strain analysis had previously shown that the gene is located on mouse chromosome 11. This assignment has been verified using interspecific backcrosses. Moreover, the location of the gene relative to a fixed order of markers in the proximal region of mouse chromosome 11 has been established. The location of the gene on mouse chromosome 11 corresponds to a homologous linkage group that is conserved on human chromosome 5q. The location of the human homologue has been determined using both somatic cell hybrid genetic analysis and fluorescence in situ hybridization. These analyses have mapped the human locus U2AFBPL to human chromosome 5q23-->q31.

Animals↗
PubMed1995

Fetal corticosteroid and T4 treatment effects on lung function of surfactant-treated preterm lambs.

Three groups of sheep fetuses at 125 or 126 d gestational age randomly received a single ultrasound-guided intramuscular injection of saline, 0.5 mg/kg betamethasone, or 0.5 mg/kg betamethasone plus 50 micrograms/kg thyroxine (T4). Forty-eight hours later the fetuses were delivered, treated with a pulmonary surfactant preparation, and ventilated for 3 h. Corticosteroids alone and in combination with T4 increased FRC, compliance, and lung volumes, and decreased the protein leak into the airspace. Saturated phosphatidylcholine pool sizes recovered by alveolar washing were not changed after hormone treatment. To evaluate the function of surfactant recovered from the lambs in vivo, we treated preterm rabbits at 27 d gestational age with the large-aggregate surfactant from alveolar washes. Large-aggregate surfactants and the pulmonary surfactant preparation increased compliances and maximal lung volumes relative to those in untreated preterm rabbits. Large-aggregate surfactants improved compliance more than did the pulmonary surfactant preparation. We conclude that ultrasound-guided single fetal corticosteroid treatment followed by postnatal surfactant improved postnatal lung function in preterm lambs. Addition of T4 did not augment corticosteroid effects. The function of the exogenous surfactant was improved in premature lamb lungs independently of the fetal treatment modality.

Animals↗
PubMed1995

Clearance of surfactant protein A from rabbit lungs.

Surfactant protein A (SP-A) is a major surfactant protein with multiple biophysical, metabolic, and host defense functions. To further characterize its metabolism in vivo, we measured clearance of SP-A from adult rabbit lungs. Trace amounts of [125I]SP-A radiolabeled by the Bolton-Hunter method and mixed with [3H]dipalmitoylphosphatidylcholine (DPPC) were given intratracheally via a bronchoscope to rabbits. Groups of five to six animals were studied 10 min to 16 h after labeled surfactant administration. After collection of alveolar washes, lamellar bodies were isolated from lung tissue. Macrophages also were isolated from alveolar washes. [125I]SP-A was cleared more rapidly than DPPC from the airspaces. Both [125I]SP-A and [3H]DPPC were lost exponentially from the total lungs, with half-life values of 6.5 h for SP-A and 12 h for DPPC (P < 0.01). In macrophages, the highest radioactivities for SP-A and DPPC were at 10 to 45 min and the radiolabels subsequently disappeared similarly. In lamellar bodies, 125I and 3H radioactivities per mumol saturated phosphatidylcholine (Sat PC) increased in parallel and were highest at 2 h. Whereas radiolabeled lipids were recovered in lamellar bodies for up to 16 h, iodinated SP-A was lost, indicating less recycling of SP-A than DPPC. We previously showed independent pathways of SP-A and Sat PC secretion in rabbits. These results demonstrate the different clearance kinetics of these two principle components of surfactant.

1,2-Dipalmitoylphosphatidylcholine↗
PubMed1995

A new histochemical method for detection of sialic acids using a physical development procedure.

We have established an efficient histochemical method for demonstration of sialic acids in light microscopy. The method consists of a selective periodate oxidation-phenylhydrazine blockade and a thiocarbohydrazide-silver protein sequence followed by a physical development procedure. From the results obtained by the present experimental and control studies in tissue sections from a series of rat and mouse organs, such as stomach, duodenum, colon, liver, sublingual gland, lung, and kidney, the specificity and sensitivity of the method were sufficient. In the tissues tested, sialic acids were visualized as distinct brownish and blackish reaction products. Comparisons of the new method with the periodic acid-phenylhydrazine-Schiff (PA-P-S) or selective periodate oxidation-Schiff (PA*-S) method employed hitherto have confirmed that the new method reported here is higher in efficiency and visibility of reaction products than the latter two methods.

Animals↗
PubMed1995

Surfactant protein-B supplementation improves in vivo function of a modified natural surfactant.

The effect of the addition of surfactant protein (SP)-B or SP-B plus SP-C (SP-BC) to a surfactant made from bovine lung (Survanta) was evaluated in 27-d-gestation preterm rabbits. The animals were treated with Survanta, Survanta + 2% SP-B, Survanta + 3% SP-BC, or sheep surfactant. They were then ventilated with 3 cm H2O positive end-expiratory pressure and tidal volumes of 8 mL/kg. Survanta + 2% SP-B was prepared by adding SP-B in water to Survanta or by adding SP-B in chloroform [SP-B(Chl)] to lipid-extracted Survanta. Dynamic compliances of the Survanta + 2% SP-B(Chl)- and Survanta + 3% SP-BC-treated rabbits were greater (p < 0.05) than those treated with Survanta or Survanta + 2% SP-B in water and were comparable to sheep surfactant. Postventilation pressure-volume curves for the groups treated with Survanta supplemented with SP-B had significantly larger retained volumes on deflation compared with those treated only with Survanta (p < 0.01). The effects of ventilation style on the responses were assessed by ventilating other groups of rabbits treated with Survanta, Survanta + 0.5% SP-B(Chl), Survanta + 2% SP-B(Chl), or sheep surfactant with tidal volumes of 10 mL/kg and 0 cm H2O positive end-expiratory pressure. SP-B (2%) augmented the in vivo function of Survanta without positive end-expiratory pressure, and 0.5% SP-B had no effect. Infasurf, a surfactant with more SP-B, was more effective than Survanta when tested in the preterm rabbits. SP-B is a critical factor for optimum immediate surfactant function.

Animals↗
PubMed1995

Absolute stereostructures of hovenidulciosides A1 and A2, bioactive novel triterpene glycosides from hoveniae semen seu fructus, the seeds and fruit of Hovenia dulcis Thunb.

Two bioactive novel triterpene glycosides named hovenidulciosides A1 and A2 have been isolated from a Chinese natural medicine, Hoveniae Semen Seu Fructus, the seeds and fruit of Hovenia dulcis Thunb. (Rhamnaceae). The absolute stereostructures of hovenidulciosides A1 and A2 with a migrated 16,17-seco-dammarane skeleton have been determined on the basis of chemical and physicochemical evidence which included the X-ray crystallographic analysis of the p-bromobenzoate of their common aglycone, hovenidulcigenin A. Hovenidulciosides A1 and A2 exhibited inhibitory activity on the histamine release from rat mast cells induced by compound 48/80 or calcium ionophore A-23187.

Animals↗
PubMed1995

Change in the distribution of alpha-tocopherol stereoisomers in rats after intravenous administration.

Synthetic alpha-tocopherol (alpha-Toc) contains equal amounts of eight different stereoisomers arising from three chiral centers in the phytyl tail. Of these, the four stereoisomers with the 2R configuration are generally more active than their corresponding 2S-isomers. We investigated the change in distribution of alpha-Toc stereoisomers in the plasma and tissues after intravenously administering all-rac- and SRR-alpha-Toc acetate. The concentration of 2R-isomers in the rat plasma after administering all-roc-alpha-Toc acetate was higher than that of the 2S-isomers. On the other hand, the concentration of 2R-isomers in the liver was lower than that of 2S-isomers up to 6 h. In the rat plasma after administering only SRR-alpha-Toc acetate, no SRR-alpha-Toc was detected after 6 h, although SRR-alpha-Toc in the liver was retained at a higher level than in the other tissues. We presume that the intravenously administered 2R- and 2S-isomers were easily transported into the liver from the plasma, the 2R-isomers being preferentially released from the liver into the blood, whereas the 2S-isomers remained in the liver for up to 6 h.

Adrenal Glands↗
PubMed1995

Changes in coagulation and fibrinolytic system after local intra-arterial thrombolysis for acute ischemic stroke.

Intracerebral hemorrhagic transformation is one of the most important complications of thrombolytic therapy for acute ischemic stroke. The relationship between changes in markers for the coagulation and fibrinolytic systems and occurrence of hemorrhagic transformation was determined after local intra-arterial thrombolytic therapy using urokinase (UK) (24 patients) or recombinant tissue plasminogen activator (t-PA) (10 patients) within 6 hours of onset. All 34 patients had no hypodensity areas on initial computed tomography scans. Plasma concentrations of fibrinogen-fibrin degradation products (FDP), fibrinogen, alpha 2-plasmin inhibitor (alpha 2-PI), plasmin-alpha 2 plasmin inhibitor complex (PIC), thrombin-antithrombin III complex (TAT), and D-dimer were measured. Hemorrhagic transformation occurred in seven patients (21%) with complete or partial recanalization; four in the UK group and three in the t-PA group. Doses of the thrombolytic agents did not correlate with the incidence of hemorrhagic transformation. The FDP levels in the hemorrhagic transformation group treated with UK significantly increased immediately and 1 hour after the therapy. The alpha 2-PI activities decreased and PIC levels increased in both the hemorrhagic transformation and the nonhemorrhagic groups after the therapy. The TAT levels in both groups tended to be higher than the normal range, but there was no significant difference from the pretreatment levels. The D-dimer levels in the hemorrhagic transformation group were higher than those in the nonhemorrhagic group at 24 hours after the therapy. Furthermore, the D-dimer levels were significantly higher in patients with complete recanalization compared with those with none or partial recanalization.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Immunohistochemical investigations of parvalbumin localization in the skeletal muscle fibers of rats.

Parvalbumin (PA) is a water soluble, low-molecular weight, calcium-binding protein which has been thought to be involved in the relaxation of skeletal muscle fibers. Although it is well known that PA concentrations are higher in fast twitch fiber than slow twitch fiber, the localization of PA within the cytoplasm of single muscle fibers is still unknown. The present study, therefore, was undertaken to clarify the PA localization by immunohistochemical methods using the confocal laser scanning microscope (CLSM) and transmission electron microscope (TEM). Wistar strain male rats were fixed by vascular perfusion with 4% paraformaldehyde solution, and the extensor digitorm longus muscle was dissected out. For fluorescent antibody examination, these specimens were quickly frozen in melting isopentan and sections were cut using a cryostat at -25 degrees C. These sections were incubated in anti-PA and anti-Troponin (TR) respectively, and then exposed to Texas-Red- and FITC-labelled secondary antibodies. For TEM study, the pre-embedding method was used. Fluorescent immunohistochemical study has clearly shown that both PA and TR are located intimately in the I-band of the skeletal muscle fibers. The finding by the immunofluorescent study correlated well with those which have been seen at the ultrastructural level. The fact that PA is located in close proximity to TR is considered to be very reasonable when we consider it in terms of the muscular contraction-relaxation cycle.

Animals↗
PubMed1995

Clinical application of ultrasonic blood rheography in vertebral artery for vertigo.

In 507 vertigo cases in which circulatory velocity in the vertebral artery was determined, using ultrasonic blood rheography, the results in 150 cases (32%) were abnormal, falling appropriately into a 'laterality' group and a 'lower' group. Twenty-one patients whose clinical course was followed up showed a decrease in the side difference of their circulatory velocity, with consequent improvement in their vertigo. VBI demonstrated a poorer prognosis for the laterality group than for the normals, thus indicating a positive correlation between side difference and the effect of fluctuating blood pressure on serum lipids. Certain antivertiginous drugs had a beneficial effect on side difference, increasing the circulatory velocity.

Adolescent↗
PubMed1995

Clinical application of ultrasonic blood rheography for vertigo.

The blood flow in the vertebral artery was measured in 507 patients with vertigo using ultrasonic blood rheography. In 150 of the 507 cases (32%), abnormal findings including laterality and decreased flow were detected. Twenty-one cases whose clinical course was observed showed a decrease in the differences in velocity between sides as vertigo improved. VBI (vertebro-basilar insufficiency) showed a worse prognosis in patients with laterality compared with those without and a positive correlation was demonstrated between side differences and fluctuating blood pressure or serum lipids. Some anti-vertiginous drugs improved the difference between sides by increasing the velocity.

Adolescent↗
PubMed1995

The influence of unilateral vertebral artery occlusion on bilateral inner ear blood flow in rats.

We investigated the influence of unilateral vertebral artery (VA) occlusion on bilateral inner ear blood flow in rats using laser Doppler flowmetry for the measurement of bilateral cochlear blood flow (CBF) and photochemically initiated thrombosis for VA occlusion. BP and CBF showed little change by unilateral VA occlusion alone. However, subsequent hypotension induced by venesection not only reduced CBF but also caused imbalance between bilateral CBF reduction rates. CBF changed independently of BP, indicating the existence of a local CBF regulatory system.

Animals↗
PubMed1995

The influence of unilateral vertebral artery occlusion on brainstem and inner ear blood flow in rat.

We investigated the influence of unilateral VA occlusion on blood regulation in the brainstem and the inner ear, using laser-Doppler flowmetry in rat. Chemical control was evaluated by blood flow response to CO2 inhalation, and autoregulation by that to induced hypotension. The results were as follows: i) Unilateral VA occlusion impairs chemical control and autoregulation of brainstem blood flow and affects autoregulation in the inner ear. ii) Unilateral VA occlusion damages the potential for blood flow regulation more strongly in the brainstem than in the inner ear. These results suggest that occlusive disease within the vertebro-basilar system leads to the impairment of blood flow regulation in both the brainstem and the inner ear-more strongly in the brainstem-possibly contributing to symptoms such as vertigo and hearing disturbance, at least in certain groups of patients when hemodynamic factors such as systemic hypotension are added.

Animals↗
PubMed1995

The risk of cancer in rheumatoid patients in Japan.

In order to clarify the risk of cancer development in patients with rheumatoid arthritis (RA), the incidence of malignant tumors during a follow-up period was investigated in RA patients at the Center for Adult Diseases, Osaka, Japan. Six hundred and fifty-five eligible rheumatoid patients (131 males, 524 females) who were admitted to our institute between 1980 and 1989 were matched against the files of the Osaka Cancer Registry. Among them, a total of 26 patients (5 males, 21 females) were noted to have developed some kinds of cancer. The female RA patients demonstrated a significantly higher incidence of all cancers than the general population, with an observed/expected (O/E) ratio of 1.71 (95% confidence interval = 1.06-2.62). Cancer of the buccal cavity/pharynx and thyroid cancer also showed a higher incidence in female RA patients, with O/E ratios of 12.93 and 2.74, respectively.

Adult↗