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Biomedical subjects

T Matsuno

Publications and source records attributed to T Matsuno.

At least 127 records · Page 7Linked to original sources
PubMed1994

Multichannel taste sensor using electric potential changes in lipid membranes.

A taste sensor with a multichannel electrode was developed by using lipid membranes as a transducer of taste substances. The sensor can detect the taste in a similar manner to the human gustatory sensation by response patterns of electric potential to taste substances. The sensitivity, reproducibility and durability were superior to those of humans. The same taste as that elicited by some commercial aqueous drink was reproduced by making aqueous solution mixed from four kinds of basic taste substances, the concentrations of which were determined so that the electric-potential pattern of this mixed solution could agree well with the pattern by the drink. Different brands of beer were easily distinguished by the electric-potential patterns.

Biosensing Techniques↗
PubMed1994

The relevance of preoperative cystometrography in patients with benign prostatic hyperplasia: correlating the findings with clinical features and outcome after prostatectomy.

Preoperative water cystometrograms in 437 patients with benign prostatic hyperplasia (BPH) were examined in a retrospective study. The cystometrographic results were analyzed regarding the preoperative clinical features: patient age, presence or absence of urinary incontinence, history of urinary retention and rate of residual urine. The prognostic value in improvement in voiding difficulty and postoperative urinary incontinence was also analyzed at 1 and 6 months after elective prostatectomy. Subjective symptoms of the patients were the primary reasons for prostatectomy, the majority of which were performed by a single competent resectionist (K. T.) who evaluated the outcome but was blinded to the cystometric findings. Of these patients 263 (60.2%) had detrusor instability (group 1), while 174 did not (group 2). Vesical denervation supersensitivity to bethanechol chloride was noted in 47 of 375 patients (12.5%). The difference in clinical features was significant between the 2 groups, with group 1 showing older patient age (p < 0.01), and a greater incidence of urinary incontinence (p < 0.001) and retention (p < 0.001). The difference between groups 1 and 2 in mean bladder capacity (p < 0.01), compliance (p < 0.01) and a greater positive rate of vesical denervation supersensitivity (p < 0.001) was also significant. The clinical and cystometrographic parameters studied worsened with advancing patient age. Although the majority of the patients (94.7%) were relieved of obstructive symptoms after transurethral prostatectomy (6 months later), 113 (25.9%) were not at 1 month. Compared to 324 patients with early improvement (74.1%), those without improvement at 1 month were characterized by older age (p < 0.01), greater prevalence of preoperative incontinence (p < 0.05), retention (p < 0.01), greater residual rate (p < 0.05), a less compliant bladder (p < 0.01) and a higher positive rate of vesical denervation supersensitivity (p < 0.05). Cystometrographic findings, however, had no relevance to late (6 months) outcome of voiding difficulty. On the other hand, postoperative incontinence was noted in 100 patients (22.9%) at 1 month after transurethral prostatectomy, with the majority having episodes similar to those experienced preoperatively (70.0%) as well as detrusor instability (87.0%). They also were older (p < 0.01), and had a less compliant bladder (p < 0.01) and a higher positive rate of vesical denervation supersensitivity (p < 0.01) than did continent patients. Only 18 elderly patients (4.1%) remained incontinent 6 months later, all with a less compliant (p < 0.01) and more unstable (p < 0.01) bladder initially. The genesis of this detrusor dysfunction was believed to be aging in male patients, in whom BPH evolves and progresses. In conclusion, preoperative cystometrography in patients with BPH is valuable in that it correlated well with the clinical features and it can predict to some extent the outcome of obstructive symptoms and urinary incontinence after transurethral prostatectomy.

Age Factors↗
PubMed1994

Responses of lipid membranes of taste sensor to astringent and pungent substances.

Astringent substances and pungent substances were studied using a multichannel taste sensor with lipid membranes. The electric-potential pattern constructed of eight outputs from the membranes has information of taste quality and intensity. Pungent substances, such as capsaicin, piperine and allyl isothiocyanate, had no effect on the membrane potentials of the lipid membranes. On the other hand, astringent substances such as tannic acid, catechin, gallic acid and chlorogenic acid changed the potentials remarkably. A principal component analysis of the patterns in electric potential changes caused by the taste substances revealed the astringency is located between bitterness and sourness.

Astringents↗
PubMed1994

[Bladder calculus after augmentation ileocystoplasty in children].

Of 12 children who had undergone augmentation ileocystoplasty for treatment of neurogenic bladder, 3 developed bladder calculi 9 to 19 months after the operation. All these 3 children had simultaneously undergone procedure to ensure urinary continence together with ileocystoplasty, and postoperative persistent bacteriuria was found in these 3 children. Component of bladder calculi was magnesium-ammonium phosphate in 2 and calcium phosphate in the other child, and all were successfully removed by endoscopic lithotripsy. These data suggest that postoperative persistent bacteriuria as well as procedures to ensure urinary continence might play a role in the formation of bladder calculus after augmentation cystoplasty.

Adolescent↗
PubMed1994

Rostrocaudal polarity formation of chick optic tectum.

The optic tectum receives retinal fibers in a topographically ordered manner. For the formation of the precise connections, the tectum is believed to be positionally specified by gradients of molecules along axes. Rostrocaudal polarity of the tectum is first detectable at embryonic day 2 (E2) in the chick, by the caudorostral gradient of en expression, then by the rostrocaudal gradient of cytoarchitectonic development. Tectum rotation experiments showed that tectum rostrocaudal polarity is not determined at around 10-somite stage, but is fixed on E3. Ectopic tectum was produced in the diencephalon by transplanting the mesencephalic alar plate heterotopically. In the ectopic tectum, en expression was weakest at the caudal (nearest to the host diencephalo-mesencephalon junction) and strongest at the rostral end. Consequently, the pattern of en expression in the host and ectopic tecta was nearly a mirror image. Retinal fibers projected to the ectopic tectum in a topographic order in accordance with the inverted gradient of the en expression pattern. Ectopic tecta was also produced by heterochronal transplantations between E3 host and E2 donor, where the en pattern was preserved. Retinotectal projection pattern was also preserved, suggesting that en expression patterns are followed by retinotopic order with regard to rostrocaudal polarity.

Animals↗
PubMed1994

[Chronic fatigue syndrome and psychiatric diseases].

The chronic fatigue syndrome consists of a combination of non-specific symptoms. Some believe that the CFS is subcategory of major depression, because the symptoms are similar to those of major depression. We believe that the CFS is quite different from major depression or neurotic depression, since the CFS has no lack of initiative and effort, no inhibition which is seen in endogenous depression, and sharp fluctuations in general fatigue, anxiety, and various persisting somatic symptoms, such as, malaise and mild fever. CFS seems to be similar to the neurasthenia. It is harmful, at least, in aetiology and treatment, to neglect the diagnosis of the CFS.

Depressive Disorder↗
PubMed1994

[Lennox-Gastaut syndrome with series of spasms intermixed with tonic seizures].

A patient with Lennox-Gastaut syndrome developed an unusual feature of periodic spasms (PS), intermixed with tonic seizures. At age 14, she began to have unilateral seizures on awaking, followed by series of spasms Each spasm consisted of rotation of the head to the left and global muscle contraction of the whole body lasting for 0.5-1 second. Ictal EEGs revealed diffuse high voltage slow waves (HVSW), sometimes superimposed upon by diffuse low voltage fast activity, which was related to the increase of muscle activity following the spasms. When the duration of the fast activity on EEG became longer than 2 seconds, the peculiar seizures consisting of combination of asymmetrical spasms and tonic seizures occurred. It is speculated that the fast activity superimposed on HVSW seen in PS represents a transition from PS to tonic seizures.

Adolescent↗
PubMed1993

Plasticity of avian mesencephalic polarity revealed by trajectories of tectofugal axons.

In normal E6 (sixth day of incubation) quail mesencephalons, circumferential axons originate in the tectum (the dorsal part of a mesencephalon), course in a ventral direction and split into three trajectories in the ventral region of the mesencephalon; two of them turned on the ipsilateral side of the mesencephalon, one rostrally and the other caudally, while the third crossed the ventral midline and turned caudally on the contralateral side. In this study, we examined whether the ventral part of the mesencephalon has plasticity in its rostrocaudal polarity formation. We transplanted quail mesencephalons at the 9-10 somite stage (E2) with reversed rostrocaudal orientation prior to axon outgrowth. In reversely transplanted mesencephalons, circumferential axons at E6 took the same trajectory pattern as that of normal embryos; one turned rostrally and the second caudally on the ipsilateral side, and the third one turned caudally on the contralateral side. These results indicate that the rostrocaudal polarity of the mesencephalon is not fixed at E2, and that it may develop under the influence of tissues surrounding the mesencephalon.

Animals↗
PubMed1993

Characterization of neutral glycosphingolipids in human cataractous lens.

Neutral glycosphingolipids were purified from human senile cataractous lenses by a combination of solvent extraction, Folch's partition, acetylation, and column chromatography using DEAE-Sephadex and Iatrobeads. Six major glycosphingolipids (A-F) from monohexosylceramide to pentahexosylceramide were identified by sugar composition analysis, methylation analysis, secondary ion-mass spectrometry, glycosidase digestion, and chromium trioxide oxidation. Their structures suggested that they were closely related in their metabolism: their sugar chains were in sequence and their ceramide moieties were similarly composed, namely C16:0 and C24:1 constituted most of the fatty acids, and long-chain base components were mostly C18-dihydrosphingosine with a small portion of C18-sphingosine. The sugar chains implied two pathways branching from lactosylceramide: one to globotriaosylceramide and the other to lactotriaosylceramide, which leads to the production of Le(x) glycolipid via neolacto type 2 core chain.

Amino Acid Sequence↗
PubMed1993

Evidence for autoinhibitory regulation of the c-src gene product. A possible interaction between the src homology 2 domain and autophosphorylation site.

In the previous study (Sato, K., Miki, S., Tachibana, H., Hayashi, F., Akiyama, T., and Fukami, Y. (1990) Biochem. Biophys. Res. Commun. 171, 1152-1159), we found a synthetic peptide, termed peptide A, that inhibited the kinase activity of p60v-src. The peptide A sequence corresponds to residues 137 to 157 of p60v-src which are included in the amino-terminal portion of the src homology 2 domain. In this study, we attempted to specify the inhibitory sequence in this domain and to identify its target site. The most potent peptide A derivative was one that corresponds to residues 140 through 157. The target site of peptide A was assumed to reside in the autophosphorylation site of p60v-src, since synthetic peptides containing the sequence Phe424-Pro-Ile-Lys-Trp428 which is present downstream of the autophosphorylated Tyr416 partially counteracted the inhibitory effect of peptide A. An antibody was prepared against one of such target peptides, termed pepY. Cross-linking experiments showed that 125I-labeled peptide A could bind to p60v-src blotted on a membrane, and the binding was blocked by the anti-pepY antibody but not by other anti-p60v-src antibodies. Conversely, immunoblotting of p60v-src with anti-pepY antibody was blocked by the cross-linking of peptide A to p60v-src. To our surprise, anti-pepY antibody did not affect the p60v-src activity. Furthermore, p60c-src was activated 2- to 6-fold by this antibody. These results suggest that the pepY region in the catalytic domain of p60v-src or of p60c-src is not essential for the catalytic activity but rather is involved in the negative regulation of the kinase activity of p60c-src.

Amino Acid Sequence↗
PubMed1993

Cecoureterocele: experience of three cases with special reference to the relevance of endoscopic incision.

We report three cases of cecoureterocele to emphasize the salient features of this rare clinical entity. The differentiation of it from the usual ectopic ureterocele requires careful examination of the urethra by voiding cystourethrography and cystourethroscopy. We describe the management of these three cases with special reference to the endoscopic incision of the obstructing tissue.

Child↗