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Biomedical subjects

Y Honma

Publications and source records attributed to Y Honma.

At least 235 records · Page 13Linked to original sources

[The assessment of 99mTc-HMPAO tumor scintigraphy using VX-2 tumors in rabbits].

Tumor scintigraphy using 99mTc-hexamethyl-propyleneamine oxime (99mTc-HMPAO) was performed in VX-2 tumors implanted in the muscles of the lower limbs of rabbits to evaluate the possibility that this agent could be used to estimate the blood perfusion of the tumor. The distribution of 99mTc-HMPAO in the tumor immediately after the intravenous injection of this radiopharmaceutical exhibited almost the same distribution on the static image 1 hour after administration. Tumor time-activity curve for 99mTc-HMPAO revealed initial peak after the injection followed by fading of 99mTc-HMPAO activity and subsequent gradual decrease in activity over the next 1 hour. The ratio of 99mTc-HMPAO activity in the tumor to that in normal muscle tissue during this next 1 hour was high and independent of time. These findings indicate that static 99mTc-HMPAO scintigraphy can provide qualitative but not quantitative data useful in the estimation of tumor blood perfusion. Moreover, comparison of distribution of 99mTc-HMPAO on the static images and angiographic, histological findings also suggest that static 99mTc-HMPAO images accurately reflect tumor blood perfusion.

Animals↗

Protein factors that regulate the growth and differentiation of mouse myeloid leukaemia cells.

We have purified and characterized several protein factors that regulate the growth and differentiation of mouse myeloid leukaemia M1 cells. The differentiation factor (D-factor) from conditioned medium (CM) of Ehrlich ascites tumour cells is a glycoprotein of Mr 40,000-50,000. Its amino acid sequence was found to be almost identical to that of leukaemia inhibitory factor (LIF) from Krebs II ascites cells. The differentiation inhibitory factor (I-factor) from the CM of variant M1 cell clones which were resistant to several differentiation inducers is a basic protein of apparent Mr 68,000. The growth inhibitory factor (GI-factor) that specifically inhibits the partially differentiated and still growing monocytic leukaemia M1 cells was isolated from the CM of a clone of M1 cells resistant to the differentiation inducers. This GI-factor is a basic protein with an Mr of 25,000. Regulation by these protein factors together with other known cytokines of growth and differentiation of M1 cells is reported.

Animals↗

Difference in effects of interferon-alpha and interferon-gamma on the induction of differentiation of retinoic acid-treated acute myeloid leukemia cells in primary culture.

We studied differentiation inducing effects of retinoic acid (RA), 1 alpha, 25-dihydroxyvitamin D3 (D3) and interferons (IFNs), alone and in combination, on fresh myeloid leukemic cells from 8 patients. RA not only induced the differentiation of leukemic cells in 5/8 cases, but potentiated differentiation by IFNs either in granulocytic or monocytic pathways. In particular, interferon-alpha enhanced granulocytic differentiation and interferon-gamma induced mono-macrophage differentiation of promyelocytic leukemic cells in the presence of RA. Differentiation induced by D3, alone or in combination with IFNs, was limited in all cases. RA plus IFNs might be an effective combination for differentiation therapy for some types of myeloid leukemia.

Cell Differentiation↗

Laser ureterolithotripsy with combined rigid and flexible ureterorenoscopy.

Because the pulsed dye laser can be transmitted through a thin, flexible quartz fiber a small caliber ureteroscope and flexible ureterorenoscope are applicable. Therefore, the use of a rigid or flexible ureterorenoscope was combined with laser lithotripsy to treat upper urinary tract calculi. All 14 ureteral stones below the pelvic brim were removed successfully with a rigid 7.2F (outer diameter) ureteroscope and 14 of 16 stones above the pelvic brim were removed with a flexible ureterorenoscope. Laser monotherapy was effective in 24 cases and the complementary use of forceps or electrohydraulic lithotripsy was required in 4. Two stones were lost from the visual field during endoscopic manipulation. There was no complication requiring surgical correction. The combined use of these instruments is highly successful and safe for the treatment of upper urinary tract calculi.

Adult↗

Pili of Aeromonas hydrophila: purification, characterization, and biological role.

Aeromonas hydrophila (Ae6) has 2 morphologically distinctive kinds of pili. One appeared rigid, channeled, and straight with a diameter of 9 nm (Ae6-R pili). The other looked flexible, wavy, and having helical structure with a diameter of 7 nm (Ae6-W pili). Ae6-R pili were purified and characterized. The pili consisted of a subunit protein with a molecular weight of 18 kDa as estimated by SDS-PAGE, and contained 42.3% hydrophobic amino acids and one cysteine residue. The pilus was solubilized to 18 kDa subunit protein by 2-mercaptoethanol, dithiothreitol, hydrochloric acid, or heating at 120 C for 5 min. The organism Ae6 was strongly adhesive to rabbit intestines as well as human intestines, and agglutinated erythrocytes. Anti-pili antibody (Fab fraction) did not block the adhesion. Purified Ae6-R pili did not adhere to the intestine or to the erythrocytes. However, the anti-pili Fab inhibited pellicle formation of the organisms cultured in broth, and also inhibited salt agglutination with ammonium sulfate. From these results, Ae6-R pili are not likely a colonization factor but probably play a role in the autoaggregation of the organisms.

Aeromonas↗

Pili of an Aeromonas hydrophila strain as a possible colonization factor.

Aeromonas hydrophila Ae6 had 2 morphologically distinctive kinds of pili. One appeared rigid and straight with a diameter of 9 nm (R-pili). The other appeared wavy and flexible with a diameter of 7 nm (W-pili). W-pili were very few on the cell as compared with R-pili. In this study, W-pili were purified and characterized. The pili consisted of a subunit protein with a molecular weight of 21 kDa as estimated by SDS-PAGE. There was no immunological cross-reaction between W-pili and other cellular components. The strain Ae6 and its purified W-pili adhered to human and rabbit intestine and agglutinated human and rabbit erythrocytes. Organisms pretreated with the Fab fraction of anti-pilus antibody failed to adhere to the intestine. Pretreatment of intestine with purified W-pili blocked adherence of the organisms to the intestine. These results suggest that the W-pili are the colonization factor of A. hydrophila Ae6.

Aeromonas↗

Inhibition of abl oncogene tyrosine kinase induces erythroid differentiation of human myelogenous leukemia K562 cells.

The human chronic myelogenous leukemia cell line K562 expresses a structurally altered c-abl protein with tyrosine kinase activity. Erythroid differentiation of K562 cells was induced by tyrosine kinase inhibitors, but not by other kinase inhibitors. Treatment of K562 cells with 5'd(TACTGGCCGCTG-AAGGGC)3', complementary to the second exon (codons 2 to 7) of c-abl mRNA, inhibited cell growth and induced benzidine-positive cells in a dose-dependent manner. However, exposure to the sense oligomer did not induce erythroid differentiation of the cells. These results suggest that inhibition of abl tyrosine kinase activity is closely related to induction of erythroid differentiation of K562 cells. A multidrug-resistant subline (K562R) was induced to undergo erythroid differentiation by tyrosine kinase inhibitors such as genistein or herbimycin A as effectively as the parent K562 cells were. Therefore, tyrosine kinase inhibitors might be useful as cancer chemotherapeutic agents against some multidrug-resistant leukemias having abnormally high activity of oncogene tyrosine kinase(s).

Alkaloids↗

Inhibition of proliferation and induction of differentiation of human and mouse myeloid leukemia cells by new ethyleneglycol-type nonphosphorus alkyl ether lipids.

A variety of ethyleneglycol-type nonphosphorus alkyl ether lipids, ether derivatives of diethyleneglycol in which the two hydroxyl groups were substituted with long chain alkyl and quaternary ammonioalkyl groups, were synthesized and their effects on proliferation and differentiation of cultured human (HL-60) and mouse (M1) myeloid leukemia cells were studied. Incubation with these compounds inhibited the cellular proliferation, and the cells differentiated into morphologically and functionally mature granulocytes. Of the compounds tested, 1-[2-[2-(octadecyloxy)ethoxy]ethoxy]-butylpyridinium mesylate (EG-6) was the most effective in inducing differentiation of HL-60 cells. Almost maximal induction of differentiation and inhibition of growth of HL-60 cells on day 6 were observed when the cells were treated with EG-6 for 1 day and then cultured without EG-6 for a further 5 days. The inhibitory effect of EG-6 on the leukemic cells was over 100 times more than that of 2-[2-(dodecyloxy)ethoxy]ethyl 2-pyridinioethyl phosphate, a potent antileukemic ether phospholipid.

Animals↗

[Effect of cefaclor on guinea pig platelet aggregation in vitro].

Effects of cefaclor (3-chloro-7-D-(2-phenyl-glycinamido)-3-cephem-4-carboxylic acid) on PAF, ADP, collagen, endotoxin, and thrombin-induced platelet aggregation were examined in vitro with the use of guinea pig platelet-rich plasma and washed platelets. PAF, even at concentrations lower than its minimum effective concentration, enhanced ADP- or endotoxin-induced platelet aggregation and prolonged the time to attain the maximum aggregation. PAF also enhanced collagen-induced platelet aggregation and shortened the lag time. Cefaclor (CCL) inhibited the PAF, ADP or thrombin induced platelet aggregation and shortened their maximum aggregation times at higher concentrations such as 300 micrograms/ml or more. CCL also inhibited the collagen-induced platelet aggregation and prolonged the lag time, but showed no effect on endotoxin-induced platelet aggregation. The effect of CCL was almost the same as that of latamoxef (LMOX). CCL and LMOX, however, showed no effect on cellular Ca2+ increase produced by PAF, ADP, or thrombin, suggesting that the inhibitory effect of CCL and LMOX on platelet aggregation is caused by the inhibition of fibrinogen binding to the glycoprotein IIb/IIIa complex.

Adenosine Diphosphate↗

[Clinical evaluation of bunazosin hydrochloride for the treatment of voiding disturbances due to neurogenic bladder--a double-blind study].

The therapeutic utility of bunazosin hydrochloride was evaluated by a multi-center (67 hospitals) double-blind controlled study in patients who complained of voiding disturbances due to neurogenic bladder. For means of comparison, bethanechol chloride and placebo were used as reference drugs. Bunazosin hydrochloride was orally administered 1.5 mg per day for the first week and 3.0 mg per day for two weeks thereafter (Group E). Bethanechol chloride 15 mg (Group B) and placebo (Group P) were orally administered three times daily for three weeks. Three hundred and twenty-three cases were subjected to this study. The global improvement rating was analyzed for 244 cases (83 in Group E, 78 in Group B and 83 in Group P). The global utility rating (GUR) was analyzed for 252 cases (84 in Group E, 81 in Group B and 87 in Group P). Three hundred and twenty cases (107 in Group E, 104 in Group B and 109 in Group P) were analyzed with respect to overall safety rating (OSR). The global improvement ratings (excellent and good) were 32.5% in Group E, 28.2% in Group B and 21.2% in Group P. In the evaluation of GUR, Group E was superior to Group P. In addition, the incidence judged to be useless in Group E was significantly lower than that in Group B. There were no differences in OSR among these three groups. In the total evaluation of the subjective symptoms, the rates of improvement were not different among these three groups. In the total evaluation of the objective findings, the improvement rate in Group E was significantly higher than that in Group P. In addition, the deterioration rate in Group E was significantly lower than that in Group B. In objective findings before and after administration of bunazosin hydrochloride (Group E), the volume of residual urine, the rate of residual urine and the average flow rate improved significantly However, the bladder capacity, the maximum resting bladder pressure and the maximum urethral pressure did not change significantly. Bunazosin hydrochloride improved the objective findings regardless of the bladder capacity and the maximum resting bladder pressure. These significant improvements were marked in the neurogenic bladder patients who were able to urinate and in the patients whose urethral pressure was high. There were no differences in the incidence of side effects or in the appearance of abnormal values of laboratory findings in these three groups. Neither specific signs nor serious clinical side effects except those reported previously were observed.(ABSTRACT TRUNCATED AT 400 WORDS)

Adrenergic alpha-Antagonists↗

Immunohistochemical demonstration of serotonin neuron system in the central nervous system of the Japanese dogfish, Scyliorhinus torazame (Chondrichthyes).

The distribution of serotonin immunoreactivity in the brain of the Japanese dogfish (Scyliorhinus torazame) was studied with the peroxidase-antiperoxidase immunohistochemical method with serotonin antiserum. The somata of the serotonin neurons were located in the raphe regions of the brain stem and the spinal cord. A small number of serotonergic neurons were also distributed as cerebrospinal-fluid contacting neurons in the organum vasculosum hypothalami (OVH) and the paraventricular organ (PVO). These neurons were classified into nine groups (S1-S9): spinal cord (S1), rhombencephalon (S2-S6), mesencephalon (S7), and prosencephalon (OVH, S8 and PVO, S9). Processes of the serotonin neurons were widely distributed in the central nervous system, forming dense networks in various regions. The highest concentrations of these fibers were in the dorsal area of the vagal lobe, the nucleus isthmi, the tuberculum posterium, the distal part of the PVO, and the dorsal regions of the olfactory tubercle.

Animals↗

[Coexistence of cyst and tumor in the same kidney: a case report].

A case of renal cyst associated with renal tumor is presented herein. A 40-year-old male patient visited our outpatient clinic for left renal cyst which had been found by ultrasonography on routine clinical examination. CT scan demonstrated an irregular area in the cyst wall measuring about 2 cm in thickness which showed enhancement of density with contrast medium. Magnetic resonance imaging (MRI) also demonstrated a round mass with abnormal signal on the cyst wall, protruding into the cyst cavity. Transabdominal radical nephrectomy was performed on 13 July 1987, and to the resected kidney was attached a cyst measuring 7 cm in diameter in the lower pole. Grossly, the cyst contained amorphous red-brown material which turned out to be old blood clots and the wall harbored a tumor (3.0 x 2.5 cm). Histologically, the tumor was renal cell carcinoma, the surface of which was covered with necrotic tissue. The coexistence of renal cyst and tumor is rare and 62 cases were collected from the Japanese literature including our case, and discussion was made in relation to the etiological factors.

Adult↗

[A case report of the pathognomonic relationship between idiopathic interstitial pneumonia and silicosis].

A 67 year-old male complaining of cough and exertional dyspnea was hospitalized for evaluation of an abnormal chest shadow. Chest X-ray films revealed bilateral diffuse nodular shadows, honeycombing in the lower lung fields and pleural thickening suggestive of idiopathic interstitial pneumonia. He had worked as a boilerman and painting using various materials. Transbronchial lung biopsy did not reveal silicotic nodules or asbestos bodies. Analytical electron microscopic study demonstrated amounts of free silica without other elements and asbestos fibers. This case suggests a pathognomonic relationship between idiopathic interstitial pneumonia and silica inhalation.

Biopsy↗

Induction of erythroid differentiation of K562 human leukemic cells by herbimycin A, an inhibitor of tyrosine kinase activity.

Herbimycin A, a benzoquinonoid ansamycin antibiotic, is found to reduce intracellular phosphorylation by tyrosine protein kinase. The human chronic myelogenous leukemia cell line K562 expresses a structurally altered c-abl protein with tyrosine kinase activity. When K562 cells are induced to undergo erythroid differentiation by hemin, reduction in the intracellular level of tyrosine phosphorylation occurs. In order to understand the relationship between induction of differentiation and reduction of tyrosine phosphorylation by the c-abl gene product, the effect that herbimycin A, a selective inhibitor of intracellular tyrosine kinase activity, exerts on the differentiation of K562 cells was examined. Reduction of tyrosine phosphorylation in K562 cells by herbimycin A was observed within 1 h. Noncytotoxic concentrations of herbimycin A induced erythroid differentiation of K562 cells but not of murine erythroleukemia 745A cells. The other human myeloid leukemia cell lines (HL-60, THP-1, and U937) tested were not induced to undergo cell differentiation by this antibiotic. Herbimycin A and the other well-known inducers such as hemin, butyric acid, Adriamycin, and 1-beta-D-arabinofuranosylcytosine had additive or more than additive effects on induction of erythroid differentiation of K562 cells. With respect to inhibition of cell growth, the sensitivity of K562 cells to herbimycin A was highest in the human leukemia cell lines we tested. Noncytotoxic concentrations of herbimycin enhanced the antiproliferative effect of Adriamycin or 1-beta-D-arabinofuranosylcytosine on K562 cells. Combination therapy with herbimycin A and its derivatives may be considered for use in the treatment of some types of leukemia where tyrosine kinase activities are implicated as determinants of the oncogenic state.

Benzoquinones↗

Immunocytochemical localization of S-100 protein in the hypophysis and saccus vasculosus of the elasmobranchs Mustelus manazo and Scyliorhinus torazame.

S-100 protein-immunoreactive cells were demonstrated by immunocytochemical procedures in the hypophysis and saccus vasculosus of two species of elasmobranchs (Mustelus manazo and Scyliorhinus torazame). In the saccus vasculosus of M. manazo, immunoreactivity was detectable exclusively in the fibrous portions interposed between the epithelial layer and the blood vessels. In the neurohypophysis, tanycytes and astrocytes of the median eminence were immunostained, but only a few labeled cells were found in the neurointermediate lobe. In S. torazame, the neurohypophysis displayed a similar distribution of immunoreactivity, but there were no labeled cells in the saccus vasculosus. In both species, none of the glandular cells of the hypophysis displayed immunoreactivity. Electron-microscopic examination showed that the immunostained cells in the saccus vasculosus correspond to astrocytes.

Animals↗

Normal mouse lung tissue produces a growth-inhibitory factor(s) preferential for mouse monocytic leukemia cells.

A growth-inhibitory (GI) factor, that specifically inhibits the growth of mouse monocytic leukemia cells, was found in conditioned medium of mouse lung tissue, but not in that of mouse brain, heart, liver, or kidney tissue. Conditioned medium of spleen or bone marrow cells had low GI activity. Pulmonary macrophages were as active as peritoneal and bone-marrow-derived macrophages in production of the GI activity. The GI factor inhibited the growth of murine monocytic leukemia cell lines Mm-A and J774.1, but scarcely inhibited the growth of other mouse cell lines, such as a myeloblastic leukemia cell line (M1), a Friend erythroleukemia cell line (745A) and a mammary carcinoma cell line (FM3A). It had no significant effect on the growth of human monocytic leukemia cell lines U937 and THP-1 or on the HL-60 promyelocytic leukemia cell line. These results suggest that the GI factor produced by mouse lung tissue preferentially inhibits the growth of mouse monocytic cells. The GI factor was found to be a proteinaceous substance with a molecular mass of 25 kDa. On chromatofocusing, the GI activity was eluted with Polybuffer 96/acetic acid at pH 7.2-7.5. The GI activity was not significantly decreased by heat treatment at 56 degrees C for 30 min or acid treatment (0.01 M HCl, 14 h), but the GI activity in glycosidase-treated conditioned medium of lung tissue was lost on heat treatment. The GI activity could not be neutralized with anti-(interferon alpha + beta) antibody. The activity was produced constitutively by lung tissues and its production was not stimulated appreciably by lipopolysaccharide, lectin, or poly(I).poly(C). The GI factor appears to be a cytokine unrelated to known cytokines such as tumor necrosis factor, interleukin-1, transforming growth factor beta, and interferons. These results suggest that the GI factor may be involved in negative feedback regulation of macrophage production in steady-state conditions in the lungs.

Animals↗

Monitoring of cortical blood flow during excision of arteriovenous malformation by thermal diffusion method.

The cortical blood flow adjacent to arteriovenous malformations was monitored in six patients before, during, and after excision of arteriovenous malformations using a thermal diffusion probe. In a large arteriovenous malformation, a progressive increase in cortical blood flow up to two times the preexcision value was noted with occlusion of the feeding arteries. Lowering arterial pressure to keep normal cortical blood flow during and after operation resulted in minimum brain edema and an excellent result. Direct measurement of cortical blood flow is of value in determining the precise level of hypotension to prevent brain edema and ischemia that may occur with excision of a large arteriovenous malformation.

Adult↗