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T Momose

Publications and source records attributed to T Momose.

At least 19 recordsLinked to original sources
PubMed1999

Relief of hemiballism from a basal ganglia arteriovenous malformation after radiosurgery.

A patient with a 3-year history of progressive hemiballism presented with an unruptured arteriovenous malformation (AVM) in the contralateral caudate nucleus and putamen. PET demonstrated a matched reduction of cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO2) in the basal ganglia and adjacent frontal lobe. The patient underwent radiosurgery for the AVM. After a period of no clinical change for 6 months, the movement disorder resolved by month 7 post-treatment. The AVM was successfully obliterated 2 years after irradiation without any significant change in the regional CBF or CMRO2.

Arteriovenous Malformations↗
PubMed1999

Efficient targeting of gene expression in chick embryos by microelectroporation.

During vertebrate embryonic development, a key to unraveling specific functions of gene products is the capability to manipulate expression of the gene of interest at the desired time and place. For this, we developed a 'microelectroporation' technique by which DNA can be locally introduced into a targeted site of avian embryos, restricting spatial expression of the protein products during development. This technique involved injection of DNA solution in ovo around the target tissue and pinpoint application of an electric field by tungsten electrodes, allowing efficient and reproducible targeted gene transfer, for example, into an optic vesicle, somites, cranial mesoderm and limb mesenchyme. Because of the locality of gene introduction and its expression, survival rates of the embryos were high: approximately 90% of the embryos injected in optic vesicles were alive for at least 1 day after microelectroporation. The instantaneous gene transfer into embryonic cells allowed rapid expression of protein products such as green fluorescence protein within 2.5 h with fluorescence maintained for 3 days of incubation. This improved technique provides a convenient and efficient way to express transgenes in a spatially and temporally restricted manner in chicken embryos.

Animals↗
PubMed1999

Contact area of the trapeziometacarpal joint.

Eighteen cadaver hands were studied to determine the contact area of the trapeziometacarpal joint by using silicone rubber casts. Casting material was introduced into the trapeziometacarpal joint during several motions of the thumb and the contact location was observed. The ratios of the contact area to the total joint area were calculated. The contact locations in opposition were the radial, volar, and ulnar segments of the trapezium and the dorsal, radial, and volar segments of the metacarpal. On average, 53% of the trapezium was in contact with 53% of the metacarpal in opposition, while 28% of the trapezium was in contact with 28% of the metacarpal in palmar abduction and 25% of the trapezium was in contact with 25% of the metacarpal in radial abduction. The contact area was the largest in opposition. The trapeziometacarpal joint is stable in opposition and facilitates a strong pinch.

Aged↗
PubMed1998

Method for the separation of the unconjugates and conjugates of chenodeoxycholic acid and deoxycholic acid by two-dimensional reversed-phase thin layer chromatography with methyl beta-cyclodextrin.

A simple and efficient method for the separation of individual unconjugated bile acids and their glycine- and taurine-amidated, 3-sulfated, 3-glucosylated and 3-glucuronidated conjugates is described. The method involves the use of a two-dimensional (2D) reversed-phase (RP) high-performance thin-layer chromatographic (HPTLC) technique with methyl beta-cyclodextrin (Me-beta-CD). Five major unconjugated bile acids, chenodeoxycholic acid (CDCA), deoxycholic acid (DCA), ursodeoxycholic acid and lithocholic acid, and their conjugates were examined as the solutes. A high degree of separation of individual bile acids in each homologous series was achieved on a RP-HPTLC plate by developing with aqueous methanol in the first dimension and the same solvent system containing Me-beta-CD in the second dimension. In particular, all of the six 'difficult-to-separate' pairs, unconjugated CDCA and DCA and their conjugated forms with glycine, taurine, sulfuric acid, D-glucose and D-glucuronic acid, were effectively resolved by adding Me-beta-CD in the aqueous mobile phases with the formers having larger mobilities than the latter. The application of this 2D inclusion RP-HPLC method to the separation of glycine-conjugated bile acids in human bile is also described. The present method would be useful for separating and characterizing these bile acids present in biological materials.

Bile↗
PubMed1998

Mechanism of short-term memory and repetition in conduction aphasia and related cognitive disorders: a neuropsychological, audiological and neuroimaging study.

To evaluate the role of the sub-cortical white matter and cortical areas of the supramarginal gyrus in short-term memory impairment (shortened digit or letter span) and repetition difficulty, four patients with conduction aphasia and impaired short-term memory and two patients with only short-term memory impairment were given digit span, letter span, speech audiometry and dichotic listening tests. The results showed that in most of the patients letter span was inferior to digit span and that bilateral ear suppression in the dichotic listening test was observed in two patients with a lesion in the inferior part of the supramarginal gyrus, suggesting that what was affected was phonological information and that the supramarginal gyrus was the storage site. The overlapped lesion of conduction aphasia patients with short-term memory impairment was the periventricular white matter at the upper to middle part of the trigone, while patients with only short-term memory impairment had a lesion in the inferior supramarginal gyrus in common. Thus, damage to the periventricular white matter at the trigone may yield the phonemic paraphasia characteristic of conduction aphasia, while damage to the inferior part of the supramarginal gyrus may result in the impairment of short-term memory. We believe that as a part of the mechanisms of short-term memory and repetition, phonological information is processed in the primary auditory cortex and goes through the periventricular white matter to the inferior part of the supramarginal gyrus and is temporarily stored there.

Aged↗
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↗