Search PubMed⌕ Search

Biomedical subjects

T Maeda

Publications and source records attributed to T Maeda.

At least 1,117 records · Page 62Linked to original sources

[The treatment of brain metastasis from lung cancer].

From August, 1976, through May, 1986, 111 patients with brain metastasis from lung cancer received various treatments according to their systemic conditions. Forty-two out of 55 patients without systemic metastasis were selected for surgical removal followed by radiation therapy, and the remaining 13 inoperable patients received radiation therapy alone. The median survival of the former group was 14.5 months with a 1-year survival rate of 57.2%, and was 11.0 months with a 1-year survival rate of 38.1% for the latter group. Twenty patients among the former group received intraoperative radiation therapy, and the result obtained was the same as that of the remaining 22 patients treated by surgery and conventional external radiation therapy. As to the conservative therapy applied for the 47 cases with systemic metastasis, radiation therapy, surgical decompression or steroid therapy were planned. The overall median survival of patients of this group was 3.5 months, with a 6-month survival rate of 27.7%. Radiation therapy combined with cisplatin was evaluated to be effective, showing more than 50% reduction of tumor volume in 73.9% of patients. The surgical removal of metastatic tumors should be considered for patients without systemic metastasis, and should also be followed by radiation therapy. Such cases would be expected to survive for more than 1 year, whereas there is no suitable treatment for patients with systemic metastasis.

Brain↗

[Fundamental studies on the properties of a new adriamycin delivery system involving adsorption to activated carbon particles].

Adriamycin (ADM) was absorbed onto fine particles of activated charcoal. The characteristics of this newly developed drug delivery system were then examined in vitro. Eighty micrograms of ADM was released from the charcoal reversibly, and the biological activity of ADM released from the charcoal was retained perfectly. The ADM was released so slowly and continuously that the concentration of ADM around the charcoal particles remained high for a long time. Such characteristics suggested that ADM-CH may be available for the treatment of peritonitis carcinomatosa and lymph node metastases.

Adsorption↗

Demonstration of monoamine oxidase type B in serotonergic and type A in noradrenergic neurons in the cat dorsal pontine tegmentum by an improved histochemical technique.

Application of a diaminobenzidine-coupled peroxidation method to monoamine oxidase (MAO) histochemistry demonstrates a detailed morphology of MAO-containing perikarya, dendrites, axons and fibers in the dorsal pontine tegmentum of the cat, sectioned with a vibratome. Further, utilization of specific inhibitors, deprenyl and clorgyline, also provides evidence that serotonergic neurons contain exclusively MAO-B and catecholaminergic ones contain MAO-A.

Animals↗

Molecular cloning of cDNA of S100 alpha subunit mRNA.

The primary structure of the bovine S-100 alpha mRNA on the basis of molecular cloning and sequence analysis of the cDNA are described. The sequence is composed of 532 bp which include the 282 bp of the complete coding region, 89 bp at the 5'-noncoding region, 161 bp at the 3'-noncoding region, polyadenylation signal, ATTAAA and poly(A) tail. Northern blot analysis shows that the size of S-100 alpha mRNA is about 700-800 bases long and a single mRNA occurs in bovine brain. Bovine brain contains both S100 alpha and beta subunits and their mRNAs. In contrast, the rat brain contains only S100 beta subunit and its mRNA.

Animals↗

Distribution of gamma-aminobutyric acid-immunoreactive neurons in the septal region of the rat brain.

The distribution of gamma-aminobutyric acid-immunoreactive (GABA-I) elements was examined in the septal region of the rat brain. The indirect peroxidase-antiperoxidase technique was used with anti-GABA antibodies in normal and colchicine-pretreated rats, with or without use of detergent in the incubation medium. Intraventricular injection of colchicine did not result in any change in the staining of neuronal perikarya. Intraseptal injections increased the intensity of labelling of GABA-I cell bodies in the lateral septal nucleus and increased the number of labelled cells in the medial septal nucleus and diagonal band of Broca (dbB). Triton X-100 added to the incubation media decreased the intensity of staining and number of GABA-I somata in all septal nuclei with a concentration-dependent effect. No change was observed concerning GABA-I varicosities. The septal area, including the lateral, medial, and triangular septal nuclei; the anterior rudiment of the hippocampus; the island of Calleja magna; the septofimbrial nucleus; the bed nucleus of the stria terminalis; and the dbB showed a strong reaction to anti-GABA antibodies with regard to GABA-containing surrounding structures. GABA-I axonal varicosities were observed in all the regions with an uneven distribution. The highest density was found in the dorsal and ventral parts of the lateral septal nucleus and in a band situated between the dbB and the nucleus accumbens. Labelled varicosities were frequently observed surrounding GABA-I and nonimmunoreactive cell bodies. GABA-I somata ranged from 10 to 30 micron in diameter. Small neurons were present in great number at the ventricular border and in the zona limitans. Medium-size and large neurons were mostly observed in the medial part of the dorsal lateral nucleus and in the intermediate lateral nucleus.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Class-switching from mu to gamma 3 or gamma 2b production at pre-B cell stage.

An Abelson virus-transformed murine pre-B cell line class-switched from mu to gamma 3 or gamma 2b at the pre-B stage during culture. A class-switch was mediated by the deletion mechanism of the intervening CH genes on the active chromosome. This study showed for the first time that class-switching at the pre-B cell stage was not always confined to gamma 2b production.

Animals↗

Postnatal development of serotonin nerve fibers in the somatosensory cortex of mice studied by immunohistochemistry.

Postnatal serotonin (5HT) innervation in the cerebral cortex of mice has been studied by 5HT immunohistochemistry. 5HT-like immunoreactive (5HT-LI) nerve fibers and terminals appeared to increase transiently, particularly in the somatosensory (Sm) cortex during early postnatal days. As pups grow, 5HT afferent inputs decreased rapidly to reach a similar pattern of distribution to that in adult animals. Since the transient increase was seen at a critical period (seventh postnatal day) for the differentiation of layer IV, it is suggested that increased 5HT concentrations might have an effect on thalamocortical inputs and/or cortical lamination of the developing brains.

Animals↗

Localization of monoamine oxidase (MAO) in the rat peripheral nervous system--existence of MAO-containing unmyelinated axons.

Using a new coupled peroxidation method modified by adding nickel ammonium sulfate, we demonstrated the localization of monoamine oxidase (MAO) in the rat peripheral nervous system. MAO was localized in the endothelial cells of endoneurial vessels, in Schwann cell cytoplasm encircling myelinated axons, and in some unmyelinated axons. The morphometric ratio of these MAO-containing axons to the total unmyelinated axons was 10-13%. These MAO-containing unmyelinated axons were assumed to coincide with postganglionic sympathetic noradrenergic ones passing in the sciatic nerve. Histochemical MAO staining may be utilized to identify the postganglionic sympathetic nerves in normal and pathological conditions at the electron microscopic level in particular.

Adrenergic Fibers↗

Deficiency of apolipoproteins A-I and C-III and severe coronary heart disease.

A 55-year-old woman with severe coronary arteriosclerosis and skin xanthomas is described. The patient had a normal total cholesterol level of 168 mg/dl. Her level of high-density lipoprotein cholesterol was markedly reduced (3 mg/dl). On apolipoprotein analysis, apolipoproteins A-I and C-III were not detectable, and the level of apolipoprotein A-II was found to be at a low level (3.5 mg/dl). This case may possibly belong to a distinct new disease entity of deficiencies of apolipoprotein A-I and C-III in which coronary arteriosclerosis appears prematurely and severely.

Apolipoprotein A-I↗

The role of renal kallikrein-kinin system and prostaglandins in diuresis and natriuresis following saline infusion in normotensives and essential hypertensives.

In order to clarify the significance of the renal kallikrein(KAL)-kinin(KIN) system and prostaglandins (PG) in exaggerated natriuresis in essential hypertensives, the effect of acute sodium load on urinary KAL, KIN, PG, and renal water and sodium handling were investigated in normotensives (NT) and patients with essential hypertension (EHT). Nine NT and seven EHT were studied following acute physiological saline infusion (1000 ml/2 hrs). Urine volume (UV), urinary sodium excretion (UNaV), fractional excretion of sodium (FENa), and fractional excretion of inorganic phosphorus (FEP) were measured by the clearance method. Urinary KAL and KIN were determined by direct-RIA. Urinary kininase (total, I and II) activities were measured by the kinin destroying capacity. Urinary PGE was measured by RIA. Following saline infusion, UV, UNaV, FEP, KAL, KIN and PGE significantly increased in both NT and EHT. The increases of UV, UNaV, FENa, FEP and KAL were remarkably greater in EHT than each in NT, while no significant difference was found in the increment of PGE between NT and EHT. Significantly positive correlations were observed between PGE and KAL or KIN in NT (r = 0.889, p less than 0.005; r = 0.574, p less than 0.05, respectively), but not in EHT. From these results, it was concluded that the exaggerated natriuresis observed in EHT following infusion may be significantly related to the augmentation of renal KAL-KIN system, but was not directly related to PGE.

Diuresis↗

The method of urinary total kallikrein and prekallikrein measurement, and their urinary excretions in the patients with essential hypertension.

The method of measurement for urinary total kallikrein (KAL) and preKAL in human was developed, and daily excretions of urinary total KAL, KAL and preKAL were investigated in patients with essential hypertension. Forty microliter of urine samples were incubated with or without 120 micrograms of chymotrypsin-free trypsin for total KAL or KAL, respectively. KAL was measured with direct radioimmunoassay and kininogenase assay. PreKAL was calculated by the subtraction of KAL from total KAL. The subjects of this study included 7 normotensives (NT) and 8 essential hypertensives (EHT). Daily excretions of total KAL, KAL and preKAL were significantly lower in EHT than those in NT. KAL/total KAL ratio, which reflects the conversion rate from preKAL to KAL in the kidney, was not significantly different between EHT and NT. From these results, it is suggested that decreased urinary KAL excretion in EHT is mainly caused by reduced preKAL production rather than the impaired conversion from preKAL to KAL in the kidney. It is emphasized that this method of measurement for urinary total KAL and preKAL may be a very useful tool for research of the renal kallikrein-kinin system.

Adult↗