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Biomedical subjects

Y Katayama

Publications and source records attributed to Y Katayama.

At least 667 records · Page 37Linked to original sources
PubMed1988

Reactivities of human urinary prokallikrein and kallikrein toward rabbit antibodies with special reference to enzyme immunoassay.

Human urinary prokallikrein and kallikrein have been analyzed by means of solid phase enzyme immunoassay (EIA) using rabbit antibodies. The anti-kallikrein antibody-immobilized EIA detected both kallikrein and prokallikrein. However, only kallikrein was detectable at concentrations below 20 micrograms/1. The anti-prokallikrein antibody-immobilized EIA detected both kallikrein and prokallikrein, but the binding maximum for kallikrein was about one-third less than that for prokallikrein. Similar difference in reactivity of kallikrein and prokallikrein toward each antibody was observed with immunoaffinity column chromatography and single radial immunodiffusion. The results show that immunochemical properties of human urinary prokallikrein and kallikrein differ distinctly, and conflicting results on detectability of kallikrein and prokallikrein in human urine with EIA or radioimmunoassay using the anti-kallikrein antibody was due to the difference in reactivity of the two forms of kallikrein toward the immobilized antibody.

Animals↗
PubMed1988

Immunocytochemical demonstration of glial fibrillary acidic protein in imprint smears of human brain tumors.

Papanicolaou-destained imprint smears from 24 brain tumors were investigated by means of avidin-biotin-peroxidase complex method (ABC) with the use of monoclonal antibodies against glial fibrillary acidic protein (GFAP). Positive staining reaction to GFAP antibody has been demonstrated in cells from the following tumors: astrocytoma, anaplastic astrocytoma, glioblastoma multiforme, mixed glioma, and ependymoma. The reaction for GFAP was negative for the following tumors: medulloblastoma, neurilemmoma, melanoma, hemangioblastoma, and metastatic tumors. In astrocytoma, the cell bodies and processes were positive with delicate fibrillary patterns; in anaplastic astrocytoma, cytoplasm and the processes were intensively stained. In glioblastoma multiforme, the staining patterns were also mixed, and the short, thickened processes were characteristic. Use of both a smear preparation and the immunoperoxidase staining technique is of great value in diagnosis of tumors of the central nervous system.

Antibodies, Monoclonal↗
PubMed1988

Preoperative determination of the level of spinal cord lesions from the killed end potential.

To determine preoperatively the level of lesions in acute cervical cord injury, the killed end potential of the spinal cord was recorded with a pair of electrodes placed in the spinal epidural space, one initially being placed rostrally to the lesions for obtaining recordings and the other placed caudally to the lesions for stimulation. The level associated with the largest killed end potential was clearly determined without much difficulty, with sequential recordings on stepwise withdrawal of the recording electrode, in four of five cases investigated. In two cases subjected to surgery, the recording electrode left in place at the level associated with the largest killed end potential was found to be located at, or a few millimeters below, the center of the lesions. This demonstrates the preoperative localizing value of the killed end potential for determining the level of lesions responsible for myelopathy.

Evoked Potentials↗
PubMed1988

Plasma levels of leukotriene C4, B4, slow reacting substance of anaphylaxis in chronological phases of cerebrovascular disease.

In this study we report and compare plasma leukotriene (LT) levels in seventeen (17) patients with cerebral infarction, five (5) patients with cerebral hemorrhage and twelve (12) age-matched healthy volunteers. Plasma samples were collected at intervals of 1-7 days, 8-14 days, 15-30 days and 31 days- after cerebrovascular accident. Plasma immunoreactive LTC4, LTB4 and SRS-A (Slow Reacting Substance of Anaphylaxis or total peptido-LT's) levels were measured for each sample. Immunoreactive LTC4 (and SRS-A) levels were elevated in patients with cerebral infarction whilst LTB4 levels were raised in the patients with cerebral hemorrhage. In particular, cerebral infarcted patients exhibited significantly elevated levels in phases 1-7 days and after 15 days when compared with the age-matched healthy volunteers. In patients with cerebral hemorrhage, significant increases in LTB4 were measured in days 1-7 only. These results suggest a clinical relationship between the plasma levels of LT's and cerebrovascular disease.

Adult↗
PubMed1988

Enhancement of peptidergic synaptic transmission by catecholamines in the bullfrog sympathetic ganglion.

Extracellular recordings were made from postganglionic branches or ganglion cells of the 9th or 10th ganglia of the paravertebral sympathetic chain of the bullfrog in vitro. Tetanic preganglionic stimulation, applied to nerve fibers between the 7th and 8th ganglia, elicited cholinergic (muscarinic) and non-cholinergic synaptic responses in nicotinized preparations. These were an early after-discharge (EAD) and a late after-discharge (LAD), respectively. Brief application (3-10 min) of catecholamines augmented the LAD and this augmentation continued for 90-120 min after catecholamine withdrawal. In contrast, these catecholamines did not significantly augment the EAD. The catecholamine effects were concentration-dependent within the range 1-100 microM, and the order of the potency was isoprenaline greater than adrenaline greater than noradrenaline greater than dopamine = phenylephrine. The catecholamine-induced augmentation was blocked by propranolol (0.1-1 microM) and pindolol (1-10 microM), but not by phentolamine (up to 10 microM). The catecholamine-evoked augmentation of the LAD could be mimicked by dibutyryl cyclic adenosine 3',5'-monophosphate (dbc-AMP) at 1-50 microM. However, similar concentrations of cyclic adenosine 3',5'-monophosphate (c-AMP), cyclic guanosine 3',5'-monophosphate (c-GMP) and dibutyryl c-GMP (dbc-GMP) had no effect. None of cyclic nucleotides appreciably augmented the EAD. Methylxanthines, 3-isobutyl-1-methylxanthine and caffeine, facilitated the LAD and potentiated the isoprenaline-induced augmentation of the LAD. The excitatory actions of luteinizing hormone releasing hormone (LHRH) were also enhanced by (-)-isoprenaline and dbc-AMP. The former was prevented by propranolol.(ABSTRACT TRUNCATED AT 250 WORDS)

1-Methyl-3-isobutylxanthine↗
PubMed1988

Supranormal levels of serotonin and its metabolite after raphe cell transplantation in serotonin-denervated rat hippocampus.

Transplantation of fetal raphe cells (14 days of gestation) into the adult rat hippocampus, 2 weeks following serotonin (5-HT)-denervation with intracisternal injection of 5,7-dihydroxytryptamine, can restore 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) levels in the hippocampus to far beyond normal values. Transplantation into the unilateral hippocampus produces asymmetrical turning behavior after administration of the 5-HT releasor, p-chloroamphetamine (IP), comparable to the behavior reported for rats with 5-HT denervation of the unilateral hippocampus. The effect is blocked by prior depletion of 5-HT with p-chlorophenylalanine (IP). The asymmetry in 5-HT levels are correlated with the behavioral change. These data indicate that a large amount of 5-HT is released from nerve terminals of transplanted raphe cells, and suggest that the supranormal levels of 5-HT and 5-HIAA after raphe cell transplantation are neurochemical correlates of 5-HT hyper-innervation of the hippocampus which has been reported previously.

5,7-Dihydroxytryptamine↗
PubMed1988

Regional rates of glucose utilization in the cat following concussive head injury.

Injections of [14C]-deoxyglucose ([14C]DG) were used to study rates of local cerebral glucose utilization (LCGU) in control cats and cats subjected to concussive brain injury produced by a fluid-percussion device. Studies in separate groups of animals demonstrated that the injury level selected produced transient behavioral suppression probably associated with traumatic disturbances of consciousness. LCGU was sampled near the site of fluid-percussion injury and more caudally in pontine regions. Histopathologic studies examined the possibility of hemorrhage, contusion, or breakdown of the blood-brain barrier in regions within which LCGU was calculated. These studies yielded analyses indicating that (1) the [14C]DG technique can be applied usefully to infer changes in regional levels of brain activity after concussion, (2) concussive injury produces changes in brain function that differ reliably across various regions of the central nervous system and may include both depression and focal activation of specific brain sites. Data are discussed that suggest that changes in brain activity in specific regions indicated by changes in LCGU could contribute to acute neurologic disturbances after concussion including unconsciousness.

Animals↗
PubMed1988

Transforming genes of canine adenovirus type 2.

Genes of canine adenovirus type 2 (CAd2) involved in transformation were localized and their functions investigated. Cells transformed by CAd2 whole DNA or the BamHI A fragment (leftmost 47%) totally lacked contact inhibition and were serum-independent, anchorage-independent and tumorigenic in newborn rats. All the cells transformed by the XbaI D (0 to 15.2%) and the EcoRI C (0 to 11.3%) fragments were morphologically transformed, but were serum-dependent, anchorage-dependent and not tumorigenic in newborn rats after 150 and 190 days observation, respectively, when 5 x 10(6) cells per rat were injected. No transforming activities were detected by DNA fragments smaller than EcoRI C. By Northern blot hybridization, it was shown that a 1 kb mRNA was encoded in the 0 to 45% region of the genome, and 1.1 kb and 2 kb RNAs in the 4.5 to 11% region. It was therefore suggested that these gene products are required for morphological transformation, and other gene(s) or element(s), which have not been identified, may be involved in serum independence, anchorage independence and tumorigenicity of the transformed cells.

Adenoviridae↗
PubMed1988

Corticospinal direct response in humans: identification of the motor cortex during intracranial surgery under general anaesthesia.

The corticospinal direct (D) response to stimulation of the motor cortex exposed for intracranial surgery was recorded in 20 cases from wire electrodes inserted into the spinal epidural space. The D response was obtained from stimulation of restricted areas of the cerebral cortex, that is, the hand, trunk and thigh areas of the motor cortex. The D response was resistant to anaesthesia and unaffected by muscle relaxants. Thus, recordings of the D response are useful for identifying the location of the motor cortex during intracranial surgery under general anaesthesia.

Anesthesia, General↗
PubMed1988

Brain eicosanoid levels in spontaneously hypertensive rats after ischemia with reperfusion: leukotriene C4 as a possible cause of cerebral edema.

The relation of brain eicosanoids to progression of cerebral edema was studied in stroke-resistant spontaneously hypertensive rats subjected to incomplete global brain ischemia induced by bilateral occlusion of the common carotid arteries. Thromboxane B2 and 6-keto prostaglandin F1 alpha levels were significantly elevated 5 minutes after reperfusion but returned to control levels by 30 minutes. In contrast, leukotriene C4 levels increased 2 hours after bilateral common carotid artery occlusion and peaked 30 minutes after reperfusion, with higher levels persisting until 60 minutes after reperfusion. Cerebral ischemia was accompanied by cerebral edema early after reperfusion. The edema correlated with increased leukotriene C4 levels. That the increased brain water content was causally related to an increase in leukotriene C4 was supported by results obtained following administration of the 5-lipoxygenase inhibitors ONO-LP-016 and AA-861. Both inhibitors suppressed the increased leukotriene C4 and brain water contents after reperfusion. Our results indicate that leukotriene C4 is closely associated with an induction of ischemic cerebral edema.

6-Ketoprostaglandin F1 alpha↗
PubMed1988

Influences of protein malnutrition on amino acid composition, trace metal elements and tensile strength of rat hairs.

We examined hair properties from determinations of diameter, amino acid composition, trace metal elements, and tensile strength of the hairs from protein-malnourished rats. The coarse or medium hair diameters of the experimental protein-malnourished rats had a tendency to decrease more than those of the control. Total contents of amino acids in the hairs had a tendency to decrease in the protein-deficient rats. Cystine content of rat hairs definitely decreased only in 5% wheat- and 5% rice-pattern amino acid mixture diet groups but not in 5% gluten diet and 5% casein diet groups. And many of the low-protein diet groups were significantly lower in methionine content than the control except for the 5% casein diet group. The Mg, Zn, and Fe contents in the hairs considerably increased in protein-deficient rats against the control. Tensile strength of coarse hairs in the experimental protein-malnourished rats was significantly lower than that of the control. The changes in amino acid composition of rat hair proteins are more likely to be influenced by various qualities of dietary protein or different compositions of amino acid mixtures in the diets at a similar dietary protein level. It should seriously be considered from our data whether the reduced cystine content in the hair can be regarded as an indicator of nutritional status.

Amino Acids↗
PubMed1988

[A case of urinary retention due to a female paraurethral leiomyoma].

A case of urinary retention due to a female paraurethral leiomyoma is reported. The patient was a 67-year-old female who visited our clinic complaining of urinary retention. Urinary sediment and infravenous pyelography revealed no abnormal findings. An oval-shaped mass was palpated at the anterior vaginal wall. The tumor was 7 X 6 cm in size, elastic hard in consistency, irregular surfaced and well movable. Computed tomography revealed a calcified tumor in the urethrovaginal septum extending over all the urethral length from the bladder neck to the urethral meatus. Cystourethroscopic examination revealed a bladder neck elevation. Transvaginal needle biopsy was performed and the pathological diagnosis was benign leiomyoma. Transvaginal removal of the tumor was performed under the diagnosis of female paraurethral leiomyoma. The tumor was easily dissected from the vaginal wall but was adhered rather firmly to the urethra. The origin of the tumor could not be identified. Postoperatively, urination was improved. Female paraurethral leiomyoma is rare but must be considered as a cause of urinary retention.

Aged↗
PubMed1988

[Treatment in male infertile clinic of Kaizuka Municipal Hospital].

The results of treatment of 68 idiopathic male infertile cases are reported. The follow up period was 3 years and 8 months from the time the Department of Urology, Kaizuka Municipal Hospital had opened. The main treatments were human mammary gonadotropin-human chorionic gonadotropin (HMG-HCG) therapy and high ligation of left testicular vein in the cases accompanied with varicocele. Adjuvant therapy was administration of vitamin B12, herb medicine and antibiotic agents for prostatovesiculitis. Some cases were administered clomiphene citrate. The results in 43 cases at over 10 weeks after treatment was followed. Mean sperm count and mean sperm activity rate in 11 cases accompanied with no varicocele and whose sperm count was 2 approximately 45 x 10(6)/ml were raised from 11.0 +/- 8.0 SD x 10(6)/ml and 19.1 +/- 11.4 SD% to 22.7 +/- 16.8 SD x 10(6)/ml and 26.9 +/- 18.5 SD%, respectively after 20 weeks of HMG-HCG therapy. Efficacy was 7 out of 11 (63.6%) in sperm count and 6 out of 11 (54.5%) in sperm activity rate. Pregnancy was obtained in 3 cases. Effect of HMG-HCG therapy was not observed in 8 cases accompanied with varicocele and whose sperm count was 2 approximately 45 x 10(6)/ml. High ligation of left testicular vein was effective in all of the 4 cases accompanied with varicocele and whose sperm count was 2 approximately 45 x 10(6)/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗