Search PubMed⌕ Search

Biomedical subjects

H Takagi

Publications and source records attributed to H Takagi.

At least 1,171 records · Page 65Linked to original sources
PubMed1983

Isolation from bovine brain of a novel analgesic pentapeptide, neo-kyotorphin, containing the Tyr-Arg (kyotorphin) unit.

A novel analgesic peptide, isolated from the bovine brain, was found to contain the Tyr-Arg (kyotorphin) unit at the C-terminal portion. This peptide, in the methanol-soluble fraction, was isolated by gel filtration and cation exchange chromatography. This peptide was termed "neo-kyotorphin" and the amino acid sequence is Thr-Ser-Lys-Tyr-Arg. The synthetically prepared neo-kyotorphin proved to have a dose-dependent analgesic effect in mice. The median analgesic dose, ED50 of neo-kyotorphin was 195 nmol/mouse (intracisternal injection), with the tail pinch test, and the potency was approximately equal that of Leu-enkephalin.

Amino Acids↗
PubMed1983

Ontogeny of cholecystokinin-8 containing neuron system of the rat: an immunohistochemical analysis--II. Lower brain stem.

The ontogeny of the cholecystokinin-8 neuron system in the lower brain stem of the rat was investigated by means of indirect immunofluorescence. Cholecystokinin-8-like immunoreactive structures first appeared in the primordium of the ventral tegmental area, ventral tegmental nucleus of Gudden and the area lateral to the superior central nucleus of the fetus on gestational day 17. Although cholecystokinin-8-like immunoreactive structures appeared gradually in various lower brain stem areas from this day, and developed markedly from postnatal day 6, thereafter, the ontogeny of cells and fibers was different. In general, the fibers increased in number as the rats grew and reached the maximum in adulthood, whereas the cells reached a maximum number between postnatal days 6-12, after which they decreased in number. Colchicine treatment, however, demonstrated the presence of cholecystokinin-8-like immunoreactive cells in various areas of the lower brain stem. These findings suggest that the cholecystokinin-containing neuron system is active in the adult and that cholecystokinin-containing cell somata cannot store a sufficient amount of the peptide for visualization in the absence of colchicine. Thus, it might be concluded that cholecystokinin may play an important role in the brain function of the adult as a neurotransmitter or neuromodulator, though its exact function is now open to discussion.

Animals↗
PubMed1983

Image diagnosis of parathyroid glands in chronic renal failure.

Twenty-two out of 31 patients with chronic renal failure and secondary hyperparathyroidism who underwent parathyroidectomy before operation underwent non-invasive image diagnosis of parathyroid glands by computed tomography (CT), scintigraphy with 201TlCl and 99mTcO4+, and/or ultrasonography. CT visualized 39 of 45 parathyroid glands (86.7%), weighing more than 500 mg. Scintigraphy with a subtraction method using a computer performed the diagnosis in 19 of 27 glands (70.4%). Ultrasonography detected 21 of 27 glands (77.8%). Image diagnosis was also useful in the postoperative follow-up study. The non-invasive image diagnosis of parathyroid glands in patients with chronic renal failure is thus valuable for 1) definite diagnosis of secondary hyperparathyroidism, 2) localization, and 3) diagnosis for effectiveness of conservative treatment.

Adult↗
PubMed1983

Polymorphism of parathyroid glands in patients with chronic renal failure and secondary hyperparathyroidism.

The excised parathyroid glands of twenty-one patients with secondary hyperparathyroidism due to chronic renal failure were submitted to careful histopathologic examinations including electron-microscopy. The previous history of these patients who had been on hemodialysis treatment for a certain period was relatively uniform with no association with primary hyperparathyroidism. Although eleven patients had four evenly enlarged parathyroid glands, eight patients showed four unevenly enlarged parathyroid glands with one or two glands weighing less than 100 mg. Histopathologic patterns of hyperplasia are easily divided into two distinctly different patterns, diffuse and nodular. Thirteen cases showed the same histopathological patterns of hyperplasia, either diffuse or nodular, in all excised glands. However, one or two out of four glands in eight patients evidenced a different histopathological pattern.

Adult↗
PubMed1983

Leucine-enkephalin-like immunoreactivity in the chicken retina with a special reference to its fine structures.

Leucine-enkephalin-like immunoreactivity (LEI) in the chicken retina was investigated using light and electron microscopic immunohistochemistry. A flat-mount technique for light microscopy clearly demonstrated that LEI cells were distributed widely throughout the entire retina, without any differences between the central and peripheral retinal regions. Frozen sections for light microscopy confirmed the previous findings in pigeons that LEI is localized in amacrine cells. The present electron microscopic observations confirmed the findings of light microscopy and revealed that LEI terminals make synaptic contract mainly with vesicle-containing processes that seemed to belong to the amacrine cells. The present study further suggests that LEI terminals are both pre- and postsynaptic elements onto vesicle-containing processes mentioned above.

Animals↗
PubMed1983

[Experimental studies of brain edema by infusion edema model-- biophysical changes of edema fluid in white matter of the brain].

The important changes in the area of brain edema are the accumulation and the spreading of edema fluid through the extracellular space in white matter of the brain. In this study, we described the changes of tissue resistance and compliance as the increment of accumulated volume of fluid produced by the slow infusion of normal saline or plasma into white matter of the cat brain. Adult cats (22) were tracheotomized, paralyzed with Galamine (2 mg/kg) and maintained normocapnic, normotensive under nitrous oxide anesthesia. Normal saline or plasma of their own was infused slowly through 25 gauge needle implanted into left frontal white matter by stereotaxic technique. A low compliance pressure gauge transducer was connected to the line for the measurement of inflow pressure. Tissue resistance and compliance for the movement of infused fluid into white matter were delivered from the changes of inflow pressure by adding the 3 microlitter per minutes on top of the resting steady state pressure. Values of tissue resistance in normal white matter, determined at the accumulated volume of 0.05 ml was very high (normal saline infusion: 6.42 +/- 0.61 X 10(3) mmHg/ml/min, plasma infusion: 5.47 +/- 1.43 X 10(3) mmHg/ml/min). But it decreased rapidly followed by more gradual decrease of tissue resistance became more edematous, reaching a plateau of one sixth of initial value at an infused volume of 0.5 ml. Tissue compliance changed by an opposite pattern of rapid increase and plateau to the changes of tissue resistance.

Animals↗
PubMed1983

[Study of brain edema by an infusion edema Model--the method and characteristics of the model].

In this report, we have described the way of making the infusion edema model, physiological changes of various parameters during this procedure, distribution of water content in white and gray matter and the light and electron microscopic findings of this edema model, for the further understanding of vasogenic edema of the brain. To make the infusion edema model, 25-G needle was stereotaxically inserted into the left frontal white matter of the cat brain. Through the polyethylene catheter with three way stop cock, this catheter was connected to the pressure transducer and slow infusion pump. By this way, we can monitor the pressure of infusing fluid into the white matter. Normal saline was infused with initial rate of 0.75 microliter/min for the first 2 hours. The inflow rate was increased to 1.5 microliter/min for the next one hour, and then changed to 3.0 microliters/min for maintenance inflow rate. The total amount of infused volume was 0.5 ml in this study. During making the infusion edema model, blood pressure and PaCO2 changed little. Intracranial pressure slightly increased from 5.8 to 15.1 mmHg. Pressure volume index (PVI) changed from 0.74 to 0.64, suggesting the changes of intracranial compliance. The water content measured by specific gravimetric technique showed nearly the same water contents and distribution of edema fluid in the white matter of the cat as in the cryogenic injury model. Pathological findings of this infusion edema model demonstrated that the infused liquid was accumulated in the extracellular space of white matter without damaging the tight junction, and endothelial cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1983

The effect of vitamin A depletion on antigen-stimulated trapping of peripheral lymphocytes in local lymph nodes of rats.

The effect of vitamin A depletion on antigen-stimulated trapping of peripheral lymphocytes in lymphatic organs was studied in rats. Distribution of [3H]-uridine-labelled syngenic peripheral lymphocytes was quantified by assaying radioactive content of brachial and axillary lymph nodes, spleen and liver of normal and vitamin A-depleted F344/Ducrj rats immunized with sheep red blood cells. Localization of labelled cells in the ipsilateral brachial lymph nodes of the normal rats was stimulated by three times upon immunization with sheep erythrocytes as compared with the contralateral nodes. Recruitment of cells in axillary lymph nodes, spleen and liver was not significantly different from non-immunized values. The vitamin A-depleted rats exhibited marked deterioration in antigen-stimulated trapping of labelled cells in the draining brachial lymph nodes. These results suggest that this effect of vitamin A depletion is due to derangement of integrity of lymphocyte-trapping mechanism in the draining lymph nodes and not to any change in nature of lymphocytes per se.

Animals↗