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T Momose

Publications and source records attributed to T Momose.

At least 55 records · Page 3Linked to original sources
PubMed1998

Structure-retention correlation of isomeric bile acids in inclusion high-performance liquid chromatography with methyl beta-cyclodextrin.

The structure-retention correlation of various C24 bile acid isomers was studied by the addition of methyl beta-cyclodextrin (Me-beta-CD) to mobile phases in reversed-phase high-performance liquid chromatography (HPLC). The compounds examined include a series of monosubstituted bile acids related to cholanoic acids differing from one another in the position and configuration of an oxygen-containing function (hydroxyl or oxo group) at the position C-3, C-6, C-7, or C-12 and the stereochemistry of the A/B-ring fusion (trans 5 alpha-H and cis 5 beta-H) in the steroid nucleus. The inclusion HPLC with Me-beta-CD was also applied to biologically important 4 beta- and 6-hydroxylated bile acids substituted by three to four hydroxyl groups in the 5 beta-steroid nucleus. These bile acid samples were converted into their fluorescence prelabeled 24-pyrenacyl ester derivatives and chromatographed on a Capcell Pak C18 column eluted with methanol-water mixtures in the presence or absence of 5 mM Me-beta-CD. The effects of Me-beta-CD on the retentions of each compound were correlated quantitatively to the decreasing rate of capacity factors and the relative strength of host-guest interactions. On the basis of the retention data, specific and nonspecific hydrogen-bonding interactions between the bile acids and the Me-beta-CD were discussed.

Bile Acids and Salts↗
PubMed1998

Androgen metabolism in cultured rat renal inner medullary collecting duct (IMCD) cells.

Although the stimulations of renal hypertrophy and renal erythropoietin production have been well-known androgen effects in the kidney, recent investigative progresses are further providing good evidences for androgen-regulated gene productions of key enzymes or local hormone substrates important to renal cell metabolisms and tubular functions in mouse or rat proximal tubules, respectively. It has been also reported that testosterone restores vasopressin receptors in medullary collecting ducts of the ageing rat and improves a urinary concentrating ability. Therefore in the present study we examined a metabolic pathway of androgens in cultured rat renal IMCD cells, which finally determine a urinary composition and volume. IMCD cells cultured from kidneys of male Wistar rats weighing about 200 g were incubated with serum-free culture media containing 4 nM [3H] testosterone or [3H] androstenedione for 2-48 h. Radioactive compounds in incubation media were then separated by reverse-phase high-pressure liquid chromatography (HPLC) and identified mainly on the basis of comparison of retention times of standard materials on HPLC. The main metabolites identified in testosterone or androstenedione incubation experiment were 5 alpha-dihydrotestosterone or 5 alpha-androstanedione, respectively. 5 alpha-Reductase inhibitor, MK 906, effectively inhibited the formations of these Ring A reduced metabolites. These results may suggest that rat renal IMCD cells possess 5 alpha-reductase activity, thereby converting androgens into their biologically active forms in vivo.

5-alpha Reductase Inhibitors↗
PubMed1998

A case of pathophysiologic study in Kimura's disease: measurement of cytokines and surface analysis of eosinophils.

BACKGROUND: Kimura's disease is a rare but distinctive eosinophilic inflammatory disorder of unknown etiology; few reported case studies have focused on the immunopathologic background of this unique disease. OBJECTIVE: To define better the immunopathogenetic features of Kimura's disease, we attempted to quantitatively analyze values of cytokines and soluble interleukin-2 receptor (sIL-2R) in peripheral blood (PB), as well as perform surface immunophenotypic analysis of eosinophils from a Japanese patient with chronic relapsing Kimura's disease. RESULTS: Granulocyte macrophage-colony stimulating factor (GM-CSF), tumor necrosis factor-alpha (TNF-alpha) and sIL-2R were elevated, and newly expressed antigens on eosinophils CD4, CD25, and HLA-DR were found to be involved in the pathophysiology of this disorder. CONCLUSIONS: Kimura's disease may be a disease in which activated lymphocytes release cytokines, and these released cytokines, such as GM-CSF and TNF-alpha cause eosinophil activation. These processes may be related to the pathogenesis of this disorder.

Aged↗
PubMed1998

Predominant implication of IL-5 in acute eosinophilic pneumonia: comparison with chronic eosinophilic pneumonia.

BACKGROUND: Acute eosinophilic pneumonia (AEP) is a rare disease with unknown etiology. To examine pathophysiology of AEP we measured the cell number of eosinophils and eosinophil active cytokines in the peripheral blood and bronchoalveolar lavage fluid (BALF) of AEP patients and compared the levels with those measured in chronic eosinophilic pneumonia (CEP) patients. METHODS: Cell number of eosinophils in peripheral blood and BALF from patients with AEP (n = 3) and CEP (n = 3) were measured. Eosinophil active cytokines in serum and BALF from the patients were measured using ELISA. RESULTS: Eosinophil cell number in peripheral blood was 274-1,377/mm3 in AEP and 526-2,500/mm3 in CEP. The percentages of BALF eosinophils were high in AEP and CEP. Eosinophilia disappeared after methylprednisolone pulse therapy (1 g for 3 days) in AEP, however the cell number of eosinophils gradually increased after methylprednisolone pulse therapy and then spontaneously decreased to within normal range without any further medication. The concentrations of IL-5 in AEP were very high in serum and in BALF, however the concentrations in CEP were low in serum and BALF. CONCLUSION: AEP is a disease in which eosinophil active cytokine IL-5 is predominantly involved; CEP is not. The factors involving eosinophil infiltration to inflammatory loci differ between AEP and CEP.

Acute Disease↗
PubMed1998

Effects of intracellular cyclic AMP modulators on human eosinophil survival, degranulation and CD11b expression.

BACKGROUND: Brochial asthma is characterized by infiltration of inflammatory cells such as lymphocytes and eosinophils. Theophylline is one of the most widely used drugs in the therapy of bronchial asthma, and phosphodiesterase (PDE) inhibition is thought to be an important mechanism of its anti-inflammatory actions. However, the detailed effects of PDE inhibition on eosinophils still remain unclear. METHODS: Eosinophils in peripheral blood obtained from normal subjects and patients with mild off-season allergic rhinitis were purified using CD16 negative selection. The following effects of theophylline (nonselective PDE inhibitor), KF19514 (selective PDE IV inhibitor), mirlinone (selective PDE III inhibitor), procaterol (beta2-adrenoceptor agonist) and N6, 2'-O-dibutyryladenosine 3'5'-cyclic monophosphate (dB-cAMP; AMP analogue) on eosinophils were examined: (1) survival in the presence of interleukin-5, (2) degranulation by granulocyte/macrophage colony-stimulating factor (GM-CSF) or platelet-activating factor (PAF), (3) CD11b expression under GM-CSF or PAF stimulation and (4) intracellular cAMP level. RESULTS: Eosinophil survival was inhibited by theophilline, KF19514 or procaterol. GM-CSF- or PAF-induced degranulation was inhibited by theophylline, KF19514, procaterol or dB-cAMP. CD11b up-regulation by PAF was inhibited by theophylline, KF19514 or dB-cAMP, while GM-CSF-stimulated CD11b up-regulation was not significantly inhibited by any of the drugs tested. The levels of intracellular cAMP were increased by theophylline, KF19514 and procaterol. CONCLUSIONS: Intracellular cAMP is an important factor in the regulation of eosinophil biological functions. PDE IV inhibitors and beta2-agonists are suggested to be useful for the treatment of bronchial asthma through inhibition of eosinophil effector function.

Bucladesine↗
PubMed1998

[Analysis of cerebral blood flow SPECT imaging on standard brain atlas in patients with dementia of Alzheimer type].

Statistical parametric map (SPM) has been developed by Friston et al. to analyze focal changes in rCBF induced by brain activation. This automated and objective approach has the potential of being applied to SPECT image data sets. This study evaluated an automated analysis of brain SPECT imaging in patients with dementia of Alzheimer type (DAT) using SPM95. Seventeen patients with clinically diagnosed moderate to severe DAT and nine normal control subjects were studied. The SPECT device used was a triple-headed rotation gamma camera GCA9300A/HG. All images were transformed into the standard anatomical space of the stereotactic brain atlas of Talairach and Tournoux, and then smoothed. Statistical analysis was made between DAT and normal control groups. SPM analysis of SPECT images revealed that the parieto-temporal areas and posterior cingulate gyrus of both cerebral hemispheres were significantly decreased in DAT patients compared to normal controls. In conclusion, SPM analysis of SPECT images proved to be useful in the evaluation of abnormal perfusion areas of demented patients.

Aged↗
PubMed1998

[Stepwise analysis of cerebral blood flow SPECT imaging on standard brain atlas in patients with dementia of Alzheimer's type].

Statistical parametric mapping (SPM) has been developed by Friston et al. to analyze focal changes in regional cerebral blood flow (rCBF) induced by brain activation. This automated and objective approach has the potential of being applied to single photon emission computed tomography (SPECT) image data sets. This study evaluated an automated analysis of N-isopropyl-p[123I]iodoamphetamine SPECT (123I-IMP) imaging in patients with dementia of Alzheimer's type (DAT) using statistical parametric mapping '95 (SPM'95). Eighteen patients with clinically diagnosed mild to severe DAT who were classified into two groups and ten normal control subjects were studied. The SPECT device used was a triple-headed rotation gamma camera. All images were transformed into the standard anatomical space of the stereotaxic brain atlas of Talairach and Tournoux, and then smoothed. Statistical analyses were made between severe DAT, mild DAT and normal control groups. SPM analysis of 123I-IMP SPECT images revealed that the parietotemporal association areas and posterior cingulate gyri of both cerebral hemispheres were significantly decreased in CBF in mild DAT group compared to normal controls. In comparison of DAT groups, the right hippocampal area and basal forebrain were significantly decreased in CBF in severe DAT group. In conclusion, these results obtained by SPM analysis of SPECT images suggested that the right hippocampal area and basal forebrain followed the parietotemporal association areas and posterior cingulate gyri in the reduction of the rCBF in patients with DAT.

Aged↗
PubMed1997

Effect of deadtime loss on quantitative measurement of cerebral blood flow with technetium-99m hexamethylpropylene amine oxime.

Deadtime count loss may cause error in quantitative measurements with a gamma camera. We evaluated the effect of deadtime loss on the measurement of cerebral blood flow (CBF). Radionuclide angiography with technetium-99m hexamethylpropylene amine oxime (99mTc-HMPAO) was performed in 20 patients. A reference source was placed on the periphery of the detector to monitor deadtime loss, and CBF was calculated based on the data of radionuclide angiography with and without deadtime correction. In ten patients injected with 1110 MBq of the tracer, the CBF value without correction was 9.9%+/-1.8% higher than that with correction. This shows that deadtime loss may cause significant overestimation. The difference between CBF values obtained with and without correction was smaller in ten patients with an injected dose of 370 MBq (3.0%+/-1.2%). These results suggest a substantial effect of deadtime loss on CBF as measured by radionuclide angiography and 99mTc-HMPAO.

Adolescent↗
PubMed1997

An improved synthesis of taurine- and glycine-conjugated bile acids.

A simple and efficient method for the synthesis of taurine- and glycine-conjugated bile acids is described. The condensation reaction was achieved by the simple mixing of unconjugated bile acid (1.0 eq.), taurine (2.0 eq.) (or glycinate ester), diethyl phosphorocyanidate (1.2 eq.) in the presence of triethylamine at room temperature for 30-60 min. Sample clean-up was effected by the use of a prepacked Sep-Pak C18 cartridge for reversed-phase solid extraction or by direct recrystallization, yielding the desired taurine and glycine conjugates in 89-93 and 92-96% isolated yields, respectively.

Chemistry, Organic↗
PubMed1997

Effect of mastication on regional cerebral blood flow in humans examined by positron-emission tomography with ¹⁵O-labelled water and magnetic resonance imaging.

The interaction between mastication and cerebral blood flow was studied in 12 healthy volunteers (five males and seven females) aged 18-40 years. Positron-emission tomography (PET) autoradiography was carried out after bolus injection of 1.5 GBq H₂¹⁵O (¹⁵O-labelled water) with a half life of 2 min. The PET images were superimposed on magnetic resonance images of each participant. The regional cerebral blood flow images were normalized by the global cerebral blood flow value, and subtraction images (those during gum-chewing minus those during resting) were created and recut at the magnetic resonance image slice positions. Gum specially designed for chewing training was used. Mastication increased regional cerebral blood flow in the primary sensorimotor areas by 25-28%, in the supplementary motor areas and insulae by 9-17%, and in the cerebellum and striatum by 8-11%. These increases demonstrate that chewing activates widespread regions of the brain.

Adolescent↗
PubMed1997

Pharmacokinetic analysis of benzodiazepine receptor binding of [123I]iomazenil in human brain.

PURPOSE: The purpose of this study is to evaluate the central benzodiazepine (BZP) receptor binding of iomazenil (IMZ) by pharmacokinetic analysis and to establish a methodology for the diagnosis of CNS disorders with abnormalities in BZP receptor binding. METHODS: BZP receptor binding of IMZ was analyzed kinetically using plasma concentration-time profiles and dynamic single photon emission computed tomography (SPECT) data obtained after the intravenous administration of IMZ to patients with neuropsychiatric disease. The analysis was based on a 3-compartmental model including the processes of both blood-brain barrier (BBB) transport and BZP receptor binding. RESULTS: Hydrolized metabolite of IMZ was detected in plasma, indicating the need for separation by HPLC. The BBB influx clearance and the receptor binding potential of IMZ in the medial temporal region was reduced in the epileptic patient. CONCLUSIONS: Our findings suggest the possibility of detecting the epileptic focus by using our method.

Blood-Brain Barrier↗
PubMed1997

Intercellular adhesion molecule-1 on eosinophils is involved in eosinophil protein X release induced by cytokines.

Recent evidence suggests that adhesion molecules play important roles in eosinophil functions such as degranulation and superoxide anion production. CD11b/CD18 (Mac-1) and CD49d/CD29 (VLA-4) are involved in eosinophil-endothelial adhesion through their counterligands, intercellular adhesion molecule-1 (ICAM-1; CD54) and vascular cell adhesion molecule-1 (VCAM-1), respectively. CD54 is also induced on eosinophils by cytokine stimulation. We hypothesized that CD54 on human eosinophils may participate in eosinophil degranulation. CD54 was induced on eosinophils by a combination of human recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF) and human recombinant tumour necrosis factor-alpha (rTNF-alpha) within 2 hr of incubation, as determined by flow cytometric analysis. Recombinant GM-CSF alone induced a slight but significant CD54 expression on eosinophils. Release of eosinophil protein X, an indicator of eosinophil degranulation, was induced by rGM-CSF and this effect was synergistically enhanced by adding rTNF-alpha. To determine the role of newly expressed CD54 in eosinophil degranulation, a blocking assay was performed using monoclonal antibody (mAb) against CD54 and CD18. Anti-CD18 mAb and anti-CD54 mAb markedly inhibited eosinophil degranulation induced by rGM-CSF or a combination of rGM-CSF and rTNF-alpha. On the other hand, anti-CD54 mAb had little effect on rGM-CSF- or rGM-CSF/rTNF-alpha-induced adhesion of eosinophils, whereas anti-CD18 mAb significantly inhibited eosinophil adhesion. These results indicate that CD54 on eosinophils plays an important role in the eosinophil degranulation and that eosinophils are capable of interacting with other beta 2 integrin-positive cells.

Antibodies, Monoclonal↗
PubMed1997

Frontal pure agraphia for kanji or kana: dissociation between morphology and phonology.

We present two patients with frontal pure agraphia more impaired for either kanji or kana (two separate writing systems for the Japanese language). The lesion of patient 1 (preferentially disturbed for kanji) was restricted to the foot of the middle frontal gyrus and the adjacent anterior precentral gyrus, whereas the lesion of patient 2 (preferentially disturbed for kana) included the posterior two thirds of the middle frontal gyrus. Both patients made agraphic errors (impaired recall) for kanji and agraphic or paragraphic errors (changing into other symbols) for kana. The double dissociation and the difference in types of errors between kanji writing and kana writing suggests that there are two pathways involved in writing, i.e., a morphologic route and a phonologic route. We concluded that damage to the morphologic route may yield agraphia for kanji and that damage to the phonologic route may yield agraphia for kana.

Aged↗
PubMed1997

Comparative abilities and optimal conditions for beta-glycosidase enzymes to hydrolyse the glucuronide, glucoside, and N-acetylglucosaminide conjugates of bile acids.

Enzymatic hydrolyses were described for three variants of glycosidic conjugated bile acids with one beta-glucuronidase (Helix pomatia), three beta-glucosidase (almonds, sweet almonds, and Escherichia coli), and four beta-N-acetylglucosaminidase (jack beans, bovine kidney, human placenta, and Diplococcus pneumoniae) preparations. The substrates include the beta-glucuronide, beta-glucoside, and beta-N-acetylglucosaminide conjugates of bile acids related to hyodeoxycholic, murideoxycholic, chenodeoxycholic, and ursodeoxycholic acids possessing a sugar moiety at position C-3, C-6 or C-7. The comparative abilities and optimal conditions for the beta-glycosidases to catalyze the hydrolyses of the substrates were clarified by changing pHs and incubation times. Hydrolysis rates of the bile acid glycosides with beta-glycosidase treatments were influenced by both the source of the enzyme preparations and the conjugated position of a sugar moiety in the substrates, and the 3-glucoside and 3-N-acetylglucosaminide conjugates were usually hydrolyzed more efficiently than their corresponding 6- and 7-analogs. Escherichia coli and jack bean enzymes were chosen to hydrolyse the glucosidic and N-acetylglucosaminidic conjugated bile acids, respectively.

Acetylglucosamine↗
PubMed1997

Inhibitory effects of theophylline and procaterol on eosinophil function.

Eosinophils play a crucial role in bronchial asthma. As theophylline and procaterol (beta 2-agonist) are used for the treatment of bronchial asthma, the specific functions of eosinophils in the presence of granulocyte/macrophage colony-stimulating factor (GM-CSF) or platelet activating factor (PAF) were examined using theophylline and procaterol alone and in combination. Eosinophil degranulation induced by PAF or GM-CSF was inhibited by theophylline (10(-6) M-10(-3) M and 10(-6) M to 10(-3) M, respectively) and procaterol (10(-7) M-10(-5) M and 10(-7) M-10(-5) M, respectively). The combination of 10(-4) M theophylline and various concentrations of procaterol provided higher inhibition than 10(-4) M theophylline or procaterol (10(-7) M-10(-5) M). CD11b, which is a triggering molecule for human eosinophil degranulation, showed a significantly inhibited expression of PAF stimulation with 10(-4) M theophylline. CD11b and another triggering molecule for eosinophil degranulation, CD18, showed a significantly inhibited expression of PAF stimulation using a combination of 10(-4) M theophylline and various concentrations of procaterol (10(-5) M-10(-7) M) compared with the inhibition of 10(-4) M theophylline or procaterol (10(-5) M-10(-7) M), but GM-CSF-stimulated eosinophils were not inhibited. Taken collectively, theophylline and/or procaterol have anti-inflammatory effects.

Asthma↗
PubMed1997

[Striatal dopamine D2 receptor in Parkinson disease and its related disorders assessed by C-11 NMSP and PET].

Dopamine D2 receptor binding potential (BP) was measured by C-11 N-methylspiperone (NMSP) and PET in normal healthy volunteers and patients with various neurodegenerative diseases including Parkinson disease (PD), multiple system atrophy (MSA), progressive supranuclear palsy (PSP), corticobasal degeneration (CBD), Huntington disease (HD) and so on. In normal aging process, striatal BP was decreased according to the age. In never-medicated Parkinson disease, BP was slightly elevated, which may reflect denervation hypersensitivity in postsynaptic site. In contrast, BP was reduced in MSA (SND type) and HD. C-11 NMSP and PET is useful in better understanding of pathophysiology and differential diagnosis of Parkinson disease and its related disorders.

Aging↗
PubMed1997

Adsorption of levocabastine eye drops by soft contact lenses and its effects in rabbit eyes.

PURPOSE: We evaluated the adsorption of levocabastine (LEV) eye drops onto soft contact lenses in rabbit eyes to confirm the safety of this antihistaminic and antiallergic agent. METHODS: Low- and high- water-content soft contact lenses were placed on the eyes of three rabbits for each type of soft contact lens (total: six rabbits) for 8 hours daily. LEV eye drops and physiological saline solution (used as a control) were instilled into the experimental eye and the fellow eye at a dosage of 0.1 mL per eye, at 1 hour intervals, eight times daily, for 6 consecutive days. Severity of possible eye injury was evaluated before soft contact lens insertion and after removal. RESULTS: After completion of the study, the amounts of LEV and the preservative benzalkonium chloride (BAK) adsorbed onto the soft contact lenses were assayed using high-performance liquid chromatography. There were no significant differences between the experimental solution and the control solution using Draize's method scores or slit lamp evaluation. CONCLUSION: LEV and BAK accumulated only slightly in the soft contact lenses, leading us to conclude that LEV eye drops could be used safely by soft contact lens wearers for about 1 week.

Adsorption↗