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Biomedical subjects

Y Matsui

Publications and source records attributed to Y Matsui.

At least 307 records · Page 17Linked to original sources
PubMed1993

Inhibition of mammary duct development but not alveolar outgrowth during pregnancy in transgenic mice expressing active TGF-beta 1.

The transforming growth factors beta (TGFs-beta) are potent inhibitors of cell proliferation and are usually secreted in a latent form. TGF-beta 1, TGF-beta 2, and TGF-beta 3 are expressed in distinct but overlapping patterns in the developing mouse mammary gland. To study the role of transforming growth factor-beta 1 (TGF-beta 1) in normal mammary development and in mammary neoplasia, we have constructed three transgenic mouse lines that express a simian TGF-beta 1 s223/225 mutated to produce a constitutively active product under the control of the MMTV enhancer/promoter. Expression of the transgene, as confirmed by in situ hybridization, immunohistochemistry, and Northern blot analysis, was associated with marked suppression of the normal pattern of mammary ductal tree development in female transgenics. Reduction in total ductal tree volume was observed at 7 weeks, soon after estrous begins, and was most apparent at 13 weeks, as ductal growth in the normal mammary gland declines. This effect was seen in all three lines. However, during pregnancy, alveolar outgrowths developed from the hypoplastic ductal tree, and lactation occurred, therefore, all transgenic females could feed full litters. Unlike many other transgenic mouse models in which expression of growth factors or oncogenes under control of the MMTV promoter leads to mammary epithelial hyperplasia and increased tumor formation, the MMTV-TGF-beta 1S223/225 transgene causes conditional hypoplasia of the mammary ductal tree and no spontaneous tumors have been detected in the MMTV-TGF-beta 1S223/225 transgenic animals.

Animals↗
PubMed1993

Ultrastructural study of extramammary Paget's disease--histologically showing transition from bowenoid pattern to Paget's disease pattern.

Histological, immunohistochemical, and ultrastructural studies were performed on two cases of histologically unusual extramammary Paget's disease. Histologically, the central area of the lesions showed a bowenoid pattern, and the peripheral area showed typical extramammary Paget's disease. The transition zone showed an intermediate pattern. All these areas were positive for CEA and EMA, and negative for S-100 protein. Ultrastructurally, in the intermediate pattern, the tumour cells had abundant cytoplasmic glycogen, and the widened intercellular spaces contained numerous glycogen particles, which were probably secreted by the tumour cells. It is well known that eccrine glands, but not apocrine glands, secrete glycogen particles. Therefore, the present findings suggest that some cases of extramammary Paget's disease are a proliferation of germinative cells with eccrine gland differentiation.

Aged↗
PubMed1993

Fusarium poae and Fusarium crookwellense, Fungi Responsible for the Natural Occurrence of Nivalenol in Hokkaido.

To determine the reasons for the natural occurrence of nivalenol in the northernmost area of Japan, scabby wheat was harvested from 19 crop fields in Hokkaido. Mycological surveys and analysis for mycotoxin contamination were performed. Among 13 wheat grain samples harvested in seven locations, 9, 2, and 6 samples were positive for deoxynivalenol, nivalenol, and zearalenone, respectively, at levels ranging from 0.03 to 1.28 mug/g, 0.04 to 1.22 mug/g, and 2 to 25 ng/g, respectively. The predominant Fusarium species of the scabby wheat examined were F. sporotrichioides, F. avenaceum, F. poae, and F. crookwellense. Fifteen of 48 F. poae isolates and all four F. crookwellense isolates were screened for the production of seven derivatives of trichothecenes and zearalenone respectively, on rice culture. One isolate of F. poae produced diacetoxyscirpenol alone (4.3 mug/g); seven produced nivalenol (1.3 to 23.8 mug/g), 4-acetylnivalenol (0.1 to 4.6 mug/g), and diacetoxyscirpenol (0.9 to 99.5 mug/g); and five produced nivalenol alone (0.4 to 3.5 mug/g). The remaining two isolates produced no trichothecenes. Zearalenone production was not found in any isolate of F. poae tested. All isolates of F. crookwellense produced nivalenol (0.9 to 22.5 mug/g), 4-acetylnivalenol (0.5 to 25.0 mug/g), and zearalenone (1.4 to 162.5 mug/g). From these results, it is apparent that deoxynivalenol and zearalenone, and occasionally nivalenol, occur naturally throughout Hokkaido, and it is suggested that nivalenol-producing F. poae and F. crookwellense strains are responsible for the natural contamination with nivalenol found in the northernmost area of Japan. Furthermore, it was found for the first time that several isolates of F. poae distributed in Hokkaido possessed the ability to produce both type A and type B trichothecenes.

Journal Article↗
PubMed1993

Responses to catecholamines in perfused livers of hypothalamic-lesioned rats.

The responses of hepatic glycogenolysis to catecholamines in ventromedial hypothalamus (VMH)-lesioned male rats were examined in perfused livers. Seven days after bilateral electrical lesioning of the VMH, the livers were perfused. Isoproterenol, a beta-agonist, stimulated greater glucose production in VMH-lesioned rats than in controls (32.8 vs. 5.6 mumol glucose.h-1.g liver-1), while responses to phenylephrine, an alpha-agonist, decreased significantly compared with controls (44.4 vs. 69.8 mumol glucose.h-1.g liver-1). There were no significant differences in responses of livers to glucagon and vasopressin between control and VMH-lesioned rats. Adrenodemedullation showed the same effect on beta-responses as lesions in the VMH, but no effect on alpha-responses. Plasma epinephrine levels were not detectable with the high-performance liquid chromatography analysis in VMH-lesioned rats. The periodicity of plasma corticosterone levels was observed in both VMH-lesioned and control rats, although daytime increases in plasma corticosterone were blocked by VMH lesions. These results suggest that the lesions in the VMH cause changes in the levels of adrenergic receptor and that the increase in beta-responses is caused mostly by the reduction of plasma epinephrine.

Adrenalectomy↗
PubMed1993

Effect of subadipose tissue on the variables of signal-averaged electrocardiograms in healthy subjects.

Ventricular late potentials are obtained by signal averaging of surface electrocardiograms. Late potentials have been reported to be affected by body size or left ventricular mass. However, the effect of subadipose tissue, which is known to influence QRS amplitudes of surface ECG, on the variables of late potentials has not been evaluated. The relationships between the variables of late potentials and various obesity indices were assessed in 45 men, aged 24-38 years, without structural heart disease and bundle branch blocks. QRS duration, root mean square voltage in the last 40 ms and low-amplitude signals < 40 microV were obtained by signal-averaged ECG. Left ventricular mass was determined by echocardiography. QRS duration and root mean square voltage had no correlation with body height, weight, body mass index, sum of skin folds (triceps and subscapular) or left ventricular mass. Positive linear correlations were found between low-amplitude signals and weight (r = 0.48, p < 0.002) body mass index (r = 0.54, p < 0.002), sum of skin folds (r = 0.57, p < 0.002), percent body mass index (r = 0.54, p < 0.002). Subadipose tissue may shift the onset of the 40-microV point of low-amplitude signals to the left with a consequent prolongation of low-amplitude signals by attenuation of the QRS complex. These data suggest that the use of low-amplitude signals alone or as a combination in an obese population for the definition of positive late potentials is inappropriate. The low-amplitude signal has to be used with caution in obese patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗
PubMed1993

Parasympathetic cerebrovasodilator center of the facial nerve.

Functional studies have yet to be undertaken to establish which brain region subserves the parasympathetic regulation of the cerebral circulation. Using 31 anesthetized rats with precluded cervical sympathetic trunks, we therefore attempted to perform chemical stimulation of the greater petrosal nerve (GPN) cell group, which is a subgroup of the superior salivatory nucleus and sends off axons largely to the parasympathetic pterygopalatine ganglion via the GPN component of the facial nerve. The cerebrocortical blood flow was monitored with a laser-Doppler flowmeter. Unilateral stimulation of the GPN cell group by microinjection of L-glutamate reduced the ipsilateral cerebrocortical vascular resistance, maximally by 16.4 +/- 4.1% (mean +/- SD, n = 61). The response was not mediated by the classic muscarinic receptors of the cerebral vessel wall. However, pharmacological blockade of the peripheral parasympathetic ganglia and acute and chronic bilateral removal of the parasympathetic postganglionic fibers originating in the pterygopalatine ganglion abolished the response. The present data thus provide functional evidence that the GPN cell group may constitute a parasympathetic cerebrovasodilator center.

Animals↗
PubMed1993

Effect of the leukotriene receptor antagonist ONO-1078 on extravascular lung water after coronary ligation in dogs.

To determine whether or not leukotrienes are associated with pulmonary edema after coronary ligation in dogs, we studied the effects of a specific leukotriene C4/D4 antagonist, ONO-1078, on extravascular lung water, as measured by the thermal-dye double indicator dilution method (Extravascular thermal volume, ETV). Six dogs served as a sham control (group 1). The proximal left anterior descending coronary artery was ligated for 45 min in 6 dogs (group 2), and in 6 others the coronary artery was ligated after pretreatment with ONO-1078 (1 mu/kg/min) (group 3). ETV and pulmonary arterial pressure were measured at control and 45 min after coronary ligation. In group 1, no significant change was found in ETV. Although there was no significant increase in pulmonary arterial pressure after coronary ligation, ETV significantly increased in groups 2 and 3. ETV increased more in groups 2 and 3 than in group 1, but there was no significant difference between groups 2 and 3. Thus, ONO-1078 did not effectively prevent the accumulation of extravascular lung water after coronary ligation, indicating that leukotrienes are not important mediators of pulmonary edema after myocardial ischemia.

Animals↗
PubMed1993

Application of hydroxyapatite-coated implants as support for palatal lift prostheses in edentulous patients with cleft palate: a clinical report.

A palatal lift prosthesis (PLP) is a prosthetic speech aid used to compensate for palatopharyngeal incompetence. However, it requires dental abutments to facilitate its function. In two edentulous patients with cleft palate, hydroxyapatite-coated dental implants were used to increase PLP retention. In both cases, palatopharyngeal closure was obtained and PLP function was deemed effective, as determined by speech evaluation and nasal air flow measurements, for more than 3 years. This treatment is useful for enhancing the retention of a PLP in patients who have few or no remaining natural tooth abutments.

Adult↗
PubMed1993

[Influence of epinephrine infusion on the metabolism of exogenous lipid emulsions after 70% hepatectomy in the rat].

We investigated the effects of epinephrine on the metabolism of a lipid emulsion administrated to rats after 70% hepatectomy. Sprague-Dawley rats were underwent 70% hepatectomy and then were given lipid total parenteral nutrition (lipid-TPN) for 96 h. To increase catabolism after hepatectomy, epinephrine (Bosmine) infused continuously with the lipid-TPN. With increasing doses of the epinephrine, weight loss and the increased urinary excretion of nitrogen and 3 methyl histidine were observed. This indicated that administration of epinephrine after hepatectomy produced a model of increased surgical stress. As the epinephrine dose increased the linoleic acid content of the hepatic phospholipids increased and the arachidonic acid decreased at 96 h after hepatectomy. Epinephrine apparently inhibited the activity of the delta 5.6 desaturase involved in the biosynthesis of polyunsaturated fatty acids, leading to changes of the cell membrane fatty acid composition that could possibly influence membrane function. Thus, the fatty acid composition of lipid emulsions for TPN should be tailored according to the severity of surgical stress, because the pattern of secretion of stress hormone is dependent on the degree of such stress.

Animals↗
PubMed1993

[Correlation of myocardial temperature, intramyocardial pH, and myocardial electrical activity during hyperkalemic hypothermic cardioplegic arrest to functional recovery after reperfusion].

We estimated the correlation of myocardial temperature, intramyocardial pH, and myocardial electrical activity (MEA) during hyperkalemic hypothermic cardioplegic arrest to functional recovery after reperfusion to assess those parameters as intra-operative on-line assessment of myocardial preservation during cardiac operation. Twenty dogs underwent cardiopulmonary bypass at 30 degrees C. Cardiac function was evaluated before and after two hours ascending aortic cross-clamping. The dogs were divided into four groups according to cardiac preservation methods employed. Group I (n = 6): 4 degrees C hyperkalemic crystalloid cardioplegic solution was delivered antegradely through the aorta every 30 minutes without topical cooling. Group II (n = 4): total volume of cardioplegic solution same as Group I was delivered only once without topical cooling. Group III (n = 5): cardioplegic solution same as Group I with lidocaine (100 mg/l) was delivered every 30 minutes without topical cooling. Group IV (n = 5): cardioplegic solution same as Group I was delivered every 30 minutes with topical cooling. Hearts at less than 8 degrees C during aortic cross-clamping (Group I) revealed better functional recovery (72 +/- 21%) than those over 15 degrees C (Group II-IV, 28 +/- 30%). There was no significant correlation between intramyocardial pH changes during aortic cross-clamping and functional recovery after reperfusion (R = -.2257). During aortic cross-clamping, the occurrence of MEA which was obtained directly from the electrode inserted into left ventricular anterior free wall (direct MEA) was observed in all cases. However the myocardial activities which were identified by direct MEA were not necessarily observed visually or by routine electrocardiogram.(ABSTRACT TRUNCATED AT 250 WORDS)

Action Potentials↗
PubMed1993

Measuring vision with temporally modulated stripes in infants and children with ROP.

PURPOSE: To determine differences in preferential looking (PL) acuities using stationary and temporally modulated stripe patterns in patients with various stages of retinopathy of prematurity (ROP). METHODS: We measured the PL acuities of 134 patients (ages 4 mo to 13 yr) with various stages of ROP. Patients were divided into six subgroups according to PL vision measured with stationary stripes: (1) equal to or better than 20/200 (n = 24); (2) worse than 20/200 to 20/400 (n = 10); (3) worse than 20/400 to 20/800 (n = 15); (4) worse than 20/800 to 20/1600 (n = 13); (5) worse than 20/1600 to 20/6400 (n = 26); and (6) worse than 20/6400 (n = 46; no stationary vision). RESULTS: In the group with PL acuity equal to or better than 20/200, no difference in vision was apparent between the two methods. In patients with acuities worse than 20/200 to 20/400, the temporally modulated PL acuities were 0.23 octave better than the PL acuities measured with the stationary stripes. The difference increased to 0.86 and 1.12 octaves in the groups with visual acuities worse than 20/400 to 20/800 and worse than 20/800 to 20/1600, respectively. The difference in the group with PL acuities worse than 20/1600 to 20/6400 was 1.69 octaves. The 46 patients with no stationary vision detected only the temporally modulated stripes. CONCLUSIONS: The results suggest that the PL acuity difference between the temporally modulated and stationary stripes increases with visual impairment. Measuring PL acuity with temporally modulated stripes is an important addition to the evaluation of severely visually impaired subjects.

Adolescent↗
PubMed1993

[Surgical aspects of automatic implantable cardioverter defibrillator (AICD) in patients with life-threatening ventricular tachyarrhythmias].

Implantations of automatic implantable cardioverter defibrillator were performed in five patients with life-threatening ventricular tachyarrhythmias. Preoperative diagnoses of arrhythmias were sustained ventricular tachycardia (VT) in two cases, ventricular fibrillation (VF) in two cases and sustained VT+VF in one case. Four of five cases had basic diseases respectively (broad anterior myocardial infarction, dilated cardiomyopathy, arrhythmogenic right ventricular dysplasia, hypertrophic cardiomyopathy), and the other case was idiopathic. Preoperative CTR were 43-65% (mean 57.4%) and left ventricular ejection fraction were 26-76% (mean 51.2%). Implantation of AICD was indicated for patients who survived circulatory arrest or life-threatening VT. Median sternotomy (3) or left antero-lateral thoracotomy (2) were performed for implantation of large-small patch electrodes for defibrillation. AICD generators were implanted in the pocket under abdominal rectal muscle in all cases. Postoperatively myocardial insufficiency, pericarditis, pleuritis occurred in three cases respectively. In the follow-up periods (2-25 months, mean 13 months), AICD worked effectively in two patients with spontaneous VT (6 months, 1 year after operation) and no cardiac death was experienced. We concluded that AICD system is effective for the life-threatening ventricular tachyarrhythmias, although the further estimation in longer follow-up periods are warranted.

Adult↗
PubMed1992

Malignant lymphoma of the stomach associated with systemic sarcoidosis.

The case of a patient with gastric malignant lymphoma associated with systemic sarcoidosis is reported. The patient's sarcoidosis was identified by the findings of bilateral hilar lymphadenopathy and secondary glaucoma. Biopsy of a cervical lymph node showed epithelioid cell granuloma; the sarcoidosis was diagnosed 15 years previously. She had been treated with prednisolone for 5 years until 1979. Proximal gastrectomy, splenectomy, and lymph node dissection were done in 1989. The tumor was diagnosed as malignant lymphoma of the diffuse large cell type according to the Working Formulation. There was no infiltration of lymphoma cell in the 45 dissected lymph nodes, but sarcoid nodules were observed in all nodes. Only three cases of gastric malignant lymphoma complicating sarcoidosis have been reported to the authors' knowledge. Further study should be done in support of the concept of a sarcoidosis-lymphoma syndrome.

Aged↗
PubMed1992

Derivation of pluripotential embryonic stem cells from murine primordial germ cells in culture.

Steel factor (SF) and LIF (leukemia inhibitory factor) synergistically promote the proliferation and survival of mouse primordial germ cells (PGCs), but only for a limited time period in culture. We show here that addition of bFGF to cultures in the presence of membrane-associated SF and LIF enhances the growth of PGCs and allows their continued proliferation beyond the time when they normally stop dividing in vivo. They form colonies of densely packed, alkaline phosphatase-positive, SSEA-1-positive cells resembling undifferentiated embryonic stem (ES) cells in morphology. These cultures can be maintained on feeder layers for at least 20 passages, and under appropriate conditions give rise to embryoid bodies and to multiple differentiated cell phenotypes in monolayer culture and in tumors in nude mice. PGC-derived ES cells can also contribute to chimeras when injected into host blastocysts. The long-term culture of PGCs and their reprogramming to pluripotential ES cells has important implications for germ cell biology and the induction of teratocarcinomas.

Alkaline Phosphatase↗
PubMed1992

Characterization of the factors binding to a PEPCK gene upstream hypersensitive site with LCR activity.

A previously described upstream hypersensitive site (HS) in the PEPCK gene at -4800 bp, termed HS A (1), has been characterized and determined to bind at least two factors. One of these is a member of the ubiquitous CREB/ATF family, and the second is a novel tissue specific protein, pep A. A construct carrying HS A and the PEPCK proximal promoter was tested in transgenic mice and its CAT activity compared to the proximal promoter alone. The HS A was shown to drive tissue-specific, position-independent transcription of the CAT reporter gene 2-3 fold more effectively than the proximal promoter alone, with a concommitant 4-5 fold higher expression of CAT. Protein binding activity has been localized to a 33 bp region. This region contains a CRE (2) which is shown to bind a member of the CREB/ATF family through competition assays with an oligo containing a CRE from the proximal promoter and by the appearance of a supershift when the factor/oligo complex was exposed to CREB polyclonal antibody. Through restriction enzyme digests and competition of protein binding with an oligonucleotide homologous to HS A with a mutated CRE we have characterized a putative binding site for a liver-specific factor. In vitro and 'in vivo' footprinting studies complement each other, as well as, mobility shift assay data in designating the binding site of the proteins. The CREB/ATF factor and Pep A bind independently of each other during short term incubations, however, both factors can be accomodated on the DNA substrate as a function of extended time of incubation. Preliminary biochemical analysis defines the subunit molecular mass of the CREB/ATF like proteins at 55, 42, and 35 kD, while the tissue specific material exists as a single homogeneous subunit polypeptide in SDS of molecular mass = 49 kD.

Animals↗
PubMed1992

Isolation and characterization of two novel ras superfamily genes in Saccharomyces cerevisiae.

We have isolated two novel genes, designated as RHO3 (on chromosome IX) and RHO4 (on chromosome XI), belonging to the ras superfamily, from the yeast Saccharomyces cerevisiae. Deletion of RHO4 did not affect cell growth, but deletion of RHO3 caused a severe growth delay and a decrease in cell viability. The rho3 and rho4 disrupted genes displayed synthetic lethality at 30 degrees C. RHO3 and RHO4 seem to have overlapping functions in cell growth, because the growth defect in rho3 cells was suppressed by overexpression of RHO4 despite the low homology (about 35%) at the amino acid sequence level between the RHO3 and RHO4 proteins.

Amino Acid Sequence↗