Search PubMed⌕ Search

Biomedical subjects

M Takase

Publications and source records attributed to M Takase.

At least 127 records · Page 7Linked to original sources
PubMed1990

Studies on bi-heterocyclic compounds. II. 5-substituted thiazolones.

Reactions of 4-methyl-2(3H)-thiazolones (5) with various N-alkoxycarbonyl pyridinium salts (6a--f) led to (N-alkoxycarbonyl dihydropyridyl)thiazolones (7a--f), oxidation of which yielded a new class of 5-pyridylthiazolones (8a--f). These reactions were applied to the synthesis of other azaarylthiazolones. Some of these azaarylthiazolones, particularly 5-(4-pyridyl)thiazolones (8b, c) and 5-(4-quinolyl)thiazolones (14a,b), showed positive inotropic activity with little chronotropic effect on guinea pig left atria.

Animals↗
PubMed1990

Effects of PRL and FSH on LH binding and number of Leydig cells in hypophysectomized mice.

The effects of PRL and FSH on testicular LH receptors were studied in hypophysectomized (hypox) mice. From the eleventh day after hypophysectomy, they were given 100 micrograms ovine (o) PRL and/or 2 micrograms oFSH in two injections per day for 10 days. Hypophysectomy reduced the weight of testis, epididymides and seminal vesicles, and the LH binding to the testis. Treatment with oPRL and/or oFSH in hypox mice resulted in an increase in the weight of testis and epididymides, and the LH binding per testis. There was no difference between the testicular LH binding in oFSH- and oPRL-treated mice. Histological examination showed that oPRL and/or oFSH treatment in hypox mice restored normal spermatogenesis. Administration of oFSH to hypox mice led to an increase in the number of typical Leydig cells, whereas oPRL was not effective. These results suggest that either PRL or FSH stimulates the LH binding to the testis, but that the action of PRL and FSH on the increase in testicular LH binding is different.

Animals↗
PubMed1990

The ocular penetration of topical forskolin and its effects on intraocular pressure, aqueous flow rate and cyclic AMP level in the rabbit eye.

The ocular penetration of 14C-forskolin in suspension was studied using albino rabbits. The effects of topical forskolin suspension on cyclic AMP (cAMP) synthesis, aqueous flow and intraocular pressure (IOP) were also studied. It was shown that only 0.03% of the instilled forskolin penetrated the ocular tissue. The calculated kep value for forskolin was 0.2 X 10(-4) cm/hr. The peak concentrations were calculated to be 4 X 10(-7) mole/liter, 4.6 X 10(-7) and 2.7 X 10(-7) mole/1,000 g tissue in aqueous, iris and ciliary body, respectively, after instillation of 1% forskolin suspension. Topical 1% forskolin suspension caused cAMP increase in the aqueous humor 30 minutes after instillation, but cAMP returned to baseline level 60 minutes after instillation. The cAMP level in the ciliary body was not increased by forskolin. Aqueous flow did not change, and the IOP was slightly decreased 45 and 60 minutes after instillation of forskolin suspension. The in vivo least-effective concentration of forskolin in the ciliary epithelium was considered to be about 2.7 X 10(-7) mole/1,000 g tissue. The weak IOP lowering effect of topical forskolin suspension was considered to be due to its poor ocular penetration. However, slight modification of molecular structure might increase ocular penetration. Present results suggest only a slight increase in penetrative potential would be needed to make forskolin effective in antiglaucoma therapy.

Administration, Topical↗
PubMed1990

Topical flurbiprofen in intraocular surgery on diabetic and nondiabetic patients.

Effects of topical flurbiprofen, a highly potent prostaglandin synthetase inhibitor, were evaluated during planned extracapsular cataract extraction in diabetic and nondiabetic patients. One drop of flurbiprofen 0.1% or vehicle solution was instilled preoperatively and three times a day postoperatively for seven days. Pupil size was measured at several stages throughout and after the operation. Further, intraocular pressure before and after the operation was compared. In the nondiabetic patients, aqueous cells and flare, cells in the vitreous body, and pericorneal injection were examined as postoperative inflammatory responses. In the nondiabetic patients pupillary constriction was significantly suppressed by flurbiprofen at the end of anterior capsulotomy (P less than .05) and at the end of surgery (P less than .01). In the vehicle group, postoperative reduction in intraocular pressure was significant compared with that of the flurbiprofen group. These effects were not found in the diabetic patients. Inflammatory responses were not suppressed in the flurbiprofen group compared with the control group except for pericorneal injection.

Administration, Topical↗
PubMed1989

Expression of neurofilaments in a neoplastic human salivary intercalated duct cell line or its derivatives and effect of nerve growth factor on the cellular proliferation and phenotype.

A neoplastic salivary cell line with an ultrastructure similar to that of an intercalated duct cell of the salivary gland, established from a human submandibular salivary gland, has been used in our laboratory as a model for studying mechanisms regulating cytodifferentiation in salivary glands. The expression of neurofilaments (Mr 200,000, 160,000, and 68,000) in the neoplastic human salivary intercalated duct cell line and its derivatives was found by the immunofluorescence staining technique, immunoblotting, or immunoelectron microscopy. In addition, these cells stained with Bodian impregnation and expressed specific antigens such as tubulin alpha and beta chain, HNK-1 antigen, and laminin. When these cells were cultured in the presence of nerve growth factor, only the cells with a myoepithelial cell phenotype formed the long cytoplasmic processes which were densely packed with ample microfibrils in addition to microtubule bundles, and they exhibited marked suppression of anchorage-independent and anchorage-dependent growths. These findings indicate that the characteristics of neoplastic human salivary intercalated duct cell line and its derivatives are similar to those of neuronal cells.

Biomarkers↗
PubMed1989

Synthesis and antitumor properties of N1-acyloxymethyl derivatives of bis(2,6-dioxopiperazines).

Many N1-acyloxymethyl derivatives VI of bis(2,6-dioxopiperazine) I, ICRF-154, were prepared and tested for antitumor activity. The treatment of I with formaldehyde gave a crystalline bis(N1-hydroxymethyl) derivative VII, which was acylated under various conditions to give bis(N1-acyloxymethyl) derivatives VI. Antitumor activity of VI against P388 leukemia in mice was studied. Several bis(N1-acyloxymethyl) compounds such as phenylacetyloxymethyl VI-6, methoxycarbonyloxymethyl VI-41, isobutoxycarbonyloxymethyl VI-44, and furancarboxymethyl VI-38 compounds were found to have potent antitumor activities. On the other hand, water-soluble esters having an amine or a carboxylic acid function in their acyl groups showed rather reduced activity. These bis(N1-acyloxymethyl) derivatives VI were presumably hydrolyzed into the parent bis(2,6-dioxopiperazine) I by nonspecific esterase in the body to exhibit their antitumor activity.

Animals↗
PubMed1988

New methods for removing saccades in analysis of smooth pursuit eye movement.

New computation methods for removing saccades in analysis of smooth pursuit eye movement characteristics were developed. They have removed saccades more completely than previous methods, and were very effective especially for noisy data recorded by the EOG method. The fully developed method was applicable to eye movement data in tracking of pseudo-random target movement as well as deterministic target movement. Furthermore, the methods were also useful for extracting the number and magnitudes of saccades more precisely.

Electrooculography↗
PubMed1988

Collet-Sicard syndrome after minor head trauma.

Occipital condyle fractures are rare and are usually associated with severe head and cervical spine injury. A 71-year-old man developed unilateral palsies of the 9th through 12th cranial nerves (Collet-Sicard syndrome) due to a fracture of the occipital condyle, which was diagnosed by computed tomography. He was treated conservatively and made a good recovery.

Accessory Nerve↗
PubMed1988

Cardiotonic activity of 5-methyl-6-(4-pyridyl)-2H-1,4-thiazin-3(4H)-one hydrochloride (ZSY-27).

Cardiotonic activity of a new, non-catecholamine and non-glycoside positive inotropic agent, 5-methyl-6-(4-pyridyl)-2H-1,4-thiazin-3(4H)-one hydrochloride (ZSY-27), was investigated in isolated guinea pig left atria, cat right ventricular papillary muscle and cross-circulated excised dog papillary muscle preparations, and in anesthetized open-chest dogs. In electrically driven guinea pig left atria and cat papillary muscle preparations, ZSY-27 (3 x 10(-6)-10(-4) M) increased the developed tension in a concentration-related manner. The positive inotropic effect of ZSY-27 was not blocked by propranolol (3 x 10(-8) M) in the guinea pig atria, but was significantly inhibited by carbachol (5 x 10(-6) M) in cat papillary muscle preparations. The positive inotropic effect of ZSY-27 was comparable to that of milrinone in guinea pig atria. ZSY-27 (0.01-3 mg) increased dose-dependently the developed tension in cross-circulated excised dog papillary muscle preparations as well. In anesthetized dogs, ZSY-27 (0.03-1 mg/kg, i.v.) produced a dose-dependent increase in left ventricular contractile force and a decrease in blood pressure, while the increase in heart rate was relatively small. The pharmacological profile of ZSY-27 in anesthetized dogs was similar to that of milrinone. These results suggest that ZSY-27 is potent cardiotonic agent with vasodilator activity and its effect may be partially due to an increase in the intracellular adenosine 3',5'-cyclic monophosphate level.

Animals↗
PubMed1988

Inhibitory effect of Sertoli cell-cultured media on LH binding to mouse Leydig cells in culture.

The aim of this study is to examine the influence of Sertoli cells on LH binding to Leydig cells in culture in immature mice. Leydig cells and Sertoli cells were obtained from the testes of immature C57BL/6Ncrj mice and were cultured in serum-free medium for 7 days. The LH binding to Leydig cells and the FSH binding to Sertoli cells were dependent on incubation time, the number of cells, and the amount of labelled hormone added. The dissociation constant for LH binding to Leydig cells was 7.3 x 10(-10) M. Co-culture of Leydig cells with Sertoli cells for 7 days decreased LH binding to Leydig cells. The binding was 34.9% of that to Leydig cells cultured alone. After cultivation of Leydig cells with spent Sertoli cell-cultured medium (SM) for the last 4 days of the 7-day culture period, LH binding to Leydig cells decreased to as low as 17.4% of that of the controls. For the controls, LH binding was measured in Leydig cells cultured in spent Leydig cell-cultured medium (LM). There was no difference between SM- and LM-cultures in the final survival rate or the percentage of cells showing histochemically demonstrated 3 beta-hydroxysteroid dehydrogenase activity. These data suggest that some factor or factors are secreted from the cultured Sertoli cells and inhibit the binding of LH to Leydig cells in culture.

Animals↗
PubMed1988

Radiosensitive hemangiopericytoma of the falx. Case report.

A case of a recurrent hemangiopericytoma of the falx which responded well to radiotherapy is reported. The patient was a 58-year-old woman who received a total of 6000 rads of local Linac irradiation over 6 weeks. One year after completing radiotherapy, a computerized tomography scan showed marked regression of the tumor.

Brain Neoplasms↗
PubMed1988

[A case of alpha coma in acute brainstem dysfunction--consecutive electroencephalograms and evoked potentials].

A 31-year-old woman was admitted because of severe headache and dysarthria in December 1985. Neurological examination on admission revealed severe impairment of consciousness, anisocoria, absent light reflex on the right side, and evidence of left hemiparesis, but other brainstem reflexes were intact. A CT scan taken shortly after arrival demonstrated a large hematoma in the right temporal lobe and the right cerebellum. Breathing became irregular and intubation was needed. An emergency operation was performed. After the operation the patient remained comatose without any spontaneous respiration or brainstem reflexes. The next day she was still comatose without any spontaneous movement and other neurological finding remained unchanged. An initial EEG obtained at this time showed an 8- to 9-Hz alpha rhythm of about 15-40 microV with preponderance over the posterior and central regions. Some spontaneous variability was noted. The same day, investigations of brainstem auditory evoked potential (BAEP), visual evoked potential (VEP), and somatosensory evoked potential (SEP) were performed. BAEP showed only the first, second and third waves (I-III) bilaterally. VEP was able to elicit the primary response (II-III) without the secondary response. SEP could not be obtained from the early cortical response to left median nerve stimulation, but showed N14 bilaterally and small N20 upon right median nerve stimulation. On the second day of hospitalization, a repeated EEG showed generalized slowing with loss of alpha frequency rhythms and it proved impossible for SEP to elicit N20 bilaterally. At this time, BAEP showed bilateral I-IIIth waves and VEP still showed primary response.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

[Intraoperative electrophysiological monitoring for hearing preservation in acoustic neurinoma surgery].

Five acoustic neurinomas have been operated with hearing preservation as a goal. We monitored intraoperative brainstem auditory evoked potentials (BAEP) in all five cases, electrocochleogram (ECoG) using needle electrode in external auditory meatus in four, and compound action potentials directly recorded from the cochlear nerve (CAP VIII) in three. In all five cases the tumor was totally resected and cochlear nerve was anatomically preserved. However, in only one case useful hearing was preserved with preservation of all wave forms of the BAEP. Another patient with preservation of all wave forms of BAEP and the ECoG showed postoperative severe hearing loss. Other three patients showed postoperative severe hearing loss: only Wave I of BAEP and ECoG were preserved without preservation of the CAP VIII in one whose cochlear nerve was thought to be damaged in cerebellopontine angle cistern; Wave I of BAEP, ECoG and CAP VIII were preserved in one in whom it was suggested cochlear nerve near brainstem or cochlear nucleus was damaged; none of the BAEP, ECoG and CAP VIII was preserved in one in whom it was suggested distal cochlear nerve, or internal auditory artery was damaged. These different patterns of changes suggested that different causes for the hearing loss and difficulties in hearing preservation during acoustic neurinoma surgery. Having identified the putative mechanism of the hearing loss by monitoring those potentials, suggestions are made about how such hearing loss might be avoided. For preservation of the hearing in acoustic neurinoma surgery, all of those potentials including all wave forms of BAEP, ECoG and CAP VIII should be preserved during surgery.(ABSTRACT TRUNCATED AT 250 WORDS)

Action Potentials↗
PubMed1988

[Clinicophysiological study of multimodality evoked potentials and computed tomographic findings in persistent vegetative state].

The auditory brainstem response (ABR), short latency somatosensory evoked potential (SSEP) and visual evoked potential (VEP) of patients in the persistent vegetative state (PVS) are reported, and the correlations between the electrophysiological findings and the CT scan findings with the three clinical grades of the PVS (transitional, incomplete and complete vegetative syndromes) are discussed. Twenty two patients in a vegetative state caused by subarachnoid hemorrhage (3), hypertensive intracerebral hemorrhage (5), cerebral infarction (6), head injury (3), cerebral anoxia (4) and brain tumor (1). Each evoked response was evaluated for the presence or absence of abnormalities and assigned a grade ranked I to III. Briefly an evoked response was assigned a grade I, II, III if it satisfied the respective criteria of normal, moderately abnormal and severely abnormal or absent electrical activity. On the other hand CT scan findings in the PVS were evaluated for abnormal low density areas, ventricular dilatation and enlargement of the sulci and cisterns indicative of atrophy of the brain parenchyma. SSEP and VEP were better correlated with the clinical grade than ABR, and upper brainstem atrophy and abnormal low density area in CT scan findings were more valuable as an index to expresses the clinical features than ventricular dilatation. On the basis of these results, it is concluded that studies of ABR, SSEP and VEP associated with CT scan findings in the PVS could be a useful diagnostic aid to evaluate the lesions of these patients.

Adult↗