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Biomedical subjects

M Horio

Publications and source records attributed to M Horio.

At least 73 records · Page 4Linked to original sources
PubMed1990

A new mutant, White larva, of the mosquito Toxorhynchites splendens: genetics and cannibalism.

A strain of a new body-color mutant, white larva (wl), was established from a field-collected wild-type strain of Toxorhynchites splendens. The mutant can be distinguished from the wild type in both the larval and pupal stages, but not in the adult. Crossing experiments confirmed its mode of inheritance to be a single recessive system. This is the first visible mutant found in Tx. splendens. Larvae of the wl phenotype seem to be recognized as prey by other individuals in mass larvae rearing.

Animals↗
PubMed1990

[An autopsy case of extramural malignant leiomyoblastoma of the stomach with ovarian cancer: an immunohistochemical study].

The subject was an 85-year-old woman, who had been diagnosed as having an ovarian cancer and carcinomatous peritonitis and had been treated conservatively. She subsequently died from respiratory and renal insufficiency, and the autopsy that followed revealed that her pelvic cavity had been filled by a tumorous mass that size of a child's head. Histologically, the tumor was a serous cystadenocarcinoma of the ovary. Moreover another tumor, also the approximate size of a child's head, was found sited extramurally, beneath the posterior wall mucosa of the stomach body. Histological inspection of this tumor revealed a proliferation of round oval, and spindle-shaped tumor cells. A vacuolation of the cytoplasms and karyomitosis to the extent of 10/50 HPF also were observed. Based on the findings of being positive for Vimentin and a negative EMA, this tumor was diagnosed as being a malignant leiomyoblastoma of the stomach smooth muscle. The leioblastoma is a relatively uncommon neoplasm, and recent advances in immunohistochemical staining have indicated that some of these tumors are not only of smooth muscle derivation but also of nerve origin. Therefore, this tumor, given its morphological characteristics, had been generalized in this case as a gastric stromal tumor, and with negative findings for Desmin and S-100 protein, as well as positive for Vimentin.

Aged↗
PubMed1990

[Chromosome aberrations and genes in human and experimental leukemias].

Although determination of chromosomal abnormalities may be of limited usefulness for the diagnosis of leukemia, the recent advances in the molecular mechanism associated with chromosome aberration has been rapid. Chromosome translocation in Burkitt lymphoma and chronic myeloid leukemia was the most striking evidence for the oncogene activation. Other specific chromosome abnormalities for FAB-classified leukemias are also known. Translocated type of chromosome abnormalities between immunoglobulin or T-cell receptor genes and oncogenes may also affect the T and B-cell leukemogenesis. However, the role of trisomies found in human and experimental leukemias and the gene dosages had been thought to be most important until 1982, has not been unclear. Many types of phenotypically heterogeneous leukemias have been reported. t(4 ; 11) acute leukemia is one such leukemia which shows early B-cell and myelomonocytic nature. Heterogeneous leukemias have been called biphenotypic, hybrid and acute mixed leukemias. The terminology must be used the unified. Recent trials to use paraffin-fixed tissues and bone marrow smear for molecular analysis has been successfully reported. Basic analysis on the DNA degradation mechanism revealed the enzymatic activity might play an important role before the complete fixation.

Animals↗
PubMed1990

[A case of perianeurysmal fibrosis treated by the thrombo-exclusion technique].

A very rare case of perianeurysmal fibrosis was presented. A 65-year old man was admitted with the complaint of abdominal pulsatile mass and intermittent claudication of right lower limb. Aortography revealed fusiform, calcified aneurysm of the infrarenal abdominal aorta and severe stenosis of right common iliac artery. CT scan demonstrated a soft tissue density structure around the aortic aneurysm which was enhanced after contrast medium injection. At surgery, the aneurysm had a thick, firm, smooth wall which was shiny white in appearance and adherent perianeurysmal fibrosis was marked. In order to avoid injury to surrounding tissue such as the duodenum or vena cava, thrombo-exclusion method was chosen. Histological examination of the aneurysmal wall showed fibrous tissue infiltrated with mononuclear cells such as lymphocytes and plasma cells. The postcontrast enhancement of aortic wall and perianeurysmal sheet disappeared on CT on the post-operative 57th day and no recurrence has been observed.

Aged↗
PubMed1989

Transepithelial transport of drugs by the multidrug transporter in cultured Madin-Darby canine kidney cell epithelia.

We studied transepithelial transport of 3H-labeled hydrophobic cationic drugs in epithelia formed by wild-type and by drug-resistant Madin-Darby canine kidney (MDCk) cells that had been infected with a retrovirus carrying the multidrug-resistance (MDR1) cDNA which encodes the P-glycoprotein. P-glycoprotein is an ATP consuming plasma membrane multidrug transporter responsible for the efflux of cytotoxic chemotherapeutic drugs from resistant cancer cells. Wild-type MDCK cells have small amounts of P-glycoprotein detected by immunoprecipitation. Net transepithelial transport across wild-type MDCK epithelia was demonstrated. Basal to apical flux of 100 nM vinblastine was about six times higher than apical to basal flux. Addition of unlabeled vinblastine reduced basal to apical flux of tracer and increased apical to basal flux of tracer, a pattern expected if there is a saturable pump that extrudes vinblastine at the apical plasma membrane. Daunomycin, vincristine, and actinomycin D were also actively transported and at 20 microM these agents inhibited transport of vinblastine, suggesting that wild-type MDCK cells have a common transporter for all these drugs. Vinblastine transport was also inhibited by 20 microM verapamil, which inhibits the multidrug transporter and reverses multidrug-resistance in non-polarized cells. Net transepithelial transport of all these cytotoxic drugs and of verapamil was much higher in epithelia formed by MDCK cells infected with a human MDR1 virus (MDR-MDCK) which is expressed on the apical surface of MDR-MDCK monolayers. Because the transport of these cytotoxic drugs and verapamil is increased in MDR-MDCK epithelia compared to wild-type MDCK epithelia, transport in both these cell populations can be attributed to P-glycoprotein. These results are consistent with a role for P-glycoprotein in multidrug secretory transport across the epithelium of the proximal tubule since P-glycoprotein is normally expressed on the apical membrane of proximal tubule cells.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1989

Decrease in the fluidity of brush-border membrane vesicles induced by gentamicin. A spin-labeling study.

In our previous paper (Horio et al., Biochim Biophys Acta 858: 153-160, 1986), we reported that the addition of gentamicin in vitro to rabbit renal brush-border membrane vesicles decreases the apparent Vmax of Na+-dependent D-glucose transport without affecting the apparent Km. In the present study, we investigated the effects of gentamicin on the physical state of spin-labeled rabbit renal brush-border membranes, using electron spin resonance spectrometry. Brush-border membrane vesicles were prepared from outer cortex (mainly contains early proximal tubule) and outer medulla (containing primarily late proximal tubule), and the gentamicin toxicities in both preparations were compared. Significant decreases were observed in the membrane fluidity of 5 mM gentamicin-treated brush-border membranes. The fluidity of outer cortical brush-border membranes was affected at both 25 degrees and 35 degrees, whereas that of outer medullary membranes was affected only at 35 degrees. Two different stearic acid spin labels revealed that gentamicin affected the fluidity only in the superficial region of the membranes. We also demonstrated that the gentamicin-induced decreases in Na+-dependent D-glucose transport and in the membrane fluidity were recovered by washing gentamicin-treated brush-border membranes. We suggest that gentamicin binds to the superficial region of brush-border membranes and inhibits Na+-dependent D-glucose transport across brush-border membranes through the decrease in the membrane fluidity.

Animals↗
PubMed1989

In situ DNA-RNA hybridization using in vivo bromodeoxyuridine-labeled DNA probe.

An in vivo 5'-bromodeoxyuridine (BrdUrd) labeled DNA probe was used for in situ DNA-RNA hybridization. BrdUrd was incorporated into plasmid DNA by inoculating E. coli with Luria-Bertani (LB) culture medium containing 500 mg/L of BrdUrd. After purification of the plasmid DNA, specific probes of the defined DNA fragments, which contained the cloned insert and short stretches of the vector DNA, were generated by restriction endonuclease. The enzymatic digestion pattern of the BrdUrd-labeled plasmid DNA was the same as that of the non-labeled one. BrdUrd was incorporated in 15%-20% of the total DNA, that is, about 80% of the thymidine was replaced by BrdUrd. Picogram amounts of the BrdUrd-labeled DNA probe itself and the target DNA were detectable on nitrocellulose filters in dot-blot spot and hybridization experiments using a peroxidase/diaminobenzidine combination. The BrdUrd-labeled DNA probe was efficiently hybridized with both single stranded DNA on nitrocellulose filters and cellular mRNA in in situ hybridization experiments. Through the reaction with BrdUrd in single stranded tails, hybridized probes were clearly detectable with fluorescent microscopy using a FITC-conjugated monoclonal anti-BrdUrd antibody. The in vivo labeling method did not require nick translation steps or in vitro DNA polymerase reactions. Sensitive, stable and efficient DNA probes were easily obtainable with this method.

Bromodeoxyuridine↗
PubMed1989

[An autopsied case of malignant paraganglioma of the posterior thoracic cavity].

An autopsied case of a malignant paraganglioma of the posterior thoracic cavity is reported. A 68-year-old man had complained of chest discomfort, and serial examinations revealed a functioning paraganglioma with bone metastasis. After death a pathological examination revealed that the tumors consisted of alveolarly arranged cells and well developed capillary vessels. Numerous neurosecretory granules were observed on viewing by electron microscopy. An immunohistochemical examination showed that most of the tumor cells were positive for NSE, while only a few cells were positive for the S-100 protein. These results indicate that a paraganglioma originating from the aortic sympathetic paraganglia had similar features of a carcinoid and a neuroblastoma.

Adrenal Gland Neoplasms↗
PubMed1988

[A case report of nasal infestation by the leech, Dinobdella ferox].

A 55-year-old man in Okagaki Town, Fukuoka Prefecture, pulled a nasal leech from his nostril in July 1987, after suffering from nosebleed, copious running snivels as well as unpleasant foreign body sensation in the nasal cavity. Except for nasal septum deviation, no abnormality in the ears and mouth cavity nor bleeding, ulcerous and erosive changes in the nasal cavity were found. The formalin-fixed specimen of the leech was nearly black with no definite stripes or spots, and measured 3.5 cm in length and 1.2 cm in width. Because of these and the following characteristics, viz. 1) auricles on the posterior segment were absent, 2) five pairs of eyes were present in the anterior segments with the eye pairs 3 and 4 separated by an annulus, and 3) teeth were not observed, this specimen was identified as Dinobdella ferox. This nasal leech is found widely in Southeast Asia. In Japan, some human cases of its infestation have also been reported, mainly from southern Kyushu. The leech seemed to have entered the nasal passage of the present case from a stream at a hot spring in northern Kyushu. Attention should be given to nasal leech infestation especially now that many people in Japan are eager to visit isolated hot spring resorts.

Animals↗
PubMed1988

ATP-dependent transport of vinblastine in vesicles from human multidrug-resistant cells.

Resistance of human cancer cells to multiple cytotoxic hydrophobic agents (multidrug resistance) is due to overexpression of the "MDR1" gene, whose product is the plasma membrane P-glycoprotein. Plasma membrane vesicles partially purified from multidrug-resistant human KB carcinoma cells, but not from drug-sensitive cells, accumulate [3H]vinblastine in an ATP-dependent manner. This transport is osmotically sensitive, with an apparent Km of 38 microM for ATP and of approximately equal to 2 microM for vinblastine. The nonhydrolyzable analog adenosine 5'-[beta, gamma-imido]triphosphate does not substitute for ATP but is a competitive inhibitor of ATP for the transport process. Vanadate, an ATPase inhibitor, is a potent noncompetitive inhibitor of transport. These results indicate that hydrolysis of ATP is probably required for active transport of vinblastine. Several other drugs to which multidrug-resistant cell lines are resistant inhibit transport, with relative potencies as follows: vincristine greater than actinomycin D greater than daunomycin greater than colchicine = puromycin. Verapamil and quinidine, which reverse the multidrug-resistance phenotype, are good inhibitors of the transport process. These results confirm that multidrug-resistant cells express an energy-dependent plasma membrane transporter for hydrophobic drugs, and establish a system for the detailed biochemical analysis of this transport process.

Adenosine Triphosphate↗
PubMed1988

[Chromosome abnormalities in early cancers].

The chromosome changes in early cancer had been thought to be difficult to analyse because of the technical reasons and of the complex nature of the chromosomal abnormalities as compared with hematological diseases having simple diploid karyotype. Recent advances allowed to analyse the chromosomes of solid tumors by the improved technics for cell disaggregation, short term culture, and chromosome banding. Although some advanced solid cancers kept the simple near by diploid chromosomal features, many tumors such as cervical cancers reveal complex chromosomal changes already in the pre-invasive stage. Much more data must be collected to evaluate the role of chromosomal changes in benign and early malignant tumors.

Chromosome Aberrations↗
PubMed1986

Gentamicin inhibits Na+-dependent D-glucose transport in rabbit kidney brush-border membrane vesicles.

We studied the effect of gentamicin on Na+-dependent D-glucose transport into brush-border membrane vesicles isolated from rabbit kidney outer cortex (early proximal tubule) and outer medulla (late proximal tubule) in vitro. We found the same osmotically active space and nonspecific binding between control and gentamicin-treated brush-border membrane vesicles. There was no difference in the passive permeability properties between control and gentamicin-treated brush-border membrane vesicles. Kinetic analyses of D-glucose transport into 1 mM gentamicin-treated brush-border membrane vesicles demonstrated that gentamicin decreased Vmax in the outer cortical preparation, while it did not affect Vmax in the outer medullary preparation. With regard to Km, there was no effect of gentamicin in any vesicle preparation. When brush-border membrane vesicles were incubated with higher concentrations of gentamicin, Na+-dependent D-glucose transport was inhibited dose-dependently in both outer cortical and outer medullary preparations. Dixon plots yield inhibition constant Ki = 4 mM in the outer cortical preparation and Ki = 7 mM in the outer medullary preparation. These results indicate that the Na+-dependent D-glucose transport system in early proximal tubule is more vulnerable to gentamicin toxicity than that in late proximal tubule.

Animals↗
PubMed1985

[Reevaluation of the biological control of vector mosquitoes using predatory larvae of Toxorhynchites mosquitoes].

Attempts to control mosquito-borne disease using predatory mosquitoes such as Toxorhynchites larvae have led to indefinite results for many years, mainly because of the lack of adequate species or strains of Toxorhynchites. Recent improvements of natural and artificial matings of adults in the laboratory and of mass breeding of larvae, however, have made it possible to establish laboratory colonies of most Toxorhynchites species whenever and wherever necessary. Effects of biological control by releasing large numbers of Toxorhynchites mosquitoes should be reevaluated from a new concept of comparing the usual chemical insecticides with the living and flying "insecticides" which cause no environmental pollution.

Animals↗
PubMed1985

Laboratory bionomics of Tripteroides aranoides.

Tripteroides aranoides was colonized in the laboratory. Total duration of the immature stages was ca. 3 weeks at 28 degrees C, L:D = 15.5:8.5 with an ample food supply. Retardation of 4th instar development was observed in larvae fed on insufficient food. Females were autogenous for the first clutch of eggs and required a blood meal for maturation of the second clutch. Mating was initiated in flight and copulation occurred on the cage wall. Gravid females hovered in small oblique loops above water in bamboo cups, whereupon a white egg appeared at the abdominal tip, which was propelled by the swing of the abdomen towards water surface. The females propelled eggs in the same manner into small apertures (11 x 4 mm) bored in bamboo.

Animals↗
PubMed1984

The mechanism of decreased Na+-dependent D-glucose transport in brush-border membrane vesicles from rabbit kidneys with experimental Fanconi syndrome.

In our previous paper (Yanase, M. et al. (1983) Biochim. Biophys. Acta 733, 95-101) we reported that the Na+-dependent D-glucose uptake into brush-border membrane vesicles is decreased in rabbits with experimental Fanconi syndrome (induced by anhydro-4-epitetracycline). In the present paper we investigate the mechanism underlying this decrease. D-Glucose is taken up into the osmotically active space in anhydro-4-epitetracycline-treated brush-border membrane vesicles and exhibits the same distribution volume and the same degree of nonspecific binding and trapping as in control brush-border membrane vesicles. The passive permeability properties of control and anhydro-4-epitetracycline-treated brush-border membrane vesicles are shown to be the same as measured by the time-dependence of L-glucose efflux from brush-border membrane vesicles. D-Glucose flux was measured by the equilibrium exchange procedure at constant external and internal Na+ concentrations and zero potential. Kinetic analyses of Na+-dependent D-glucose flux indicate that Vmax in anhydro-4-epitetracycline-treated brush-border membrane vesicles (79.3 +/- 7.6 nmol/min per mg protein) is significantly smaller than in control brush-border membrane vesicles (141.3 +/- 9.9 nmol/min per mg protein), while the Km values in the two cases are not different from each other (22.3 +/- 0.9 and 27.4 +/- 1.8 mM, respectively). These results suggest that Na+-dependent D-glucose carriers per se are affected by anhydro-4-epitetracycline, and that this disorder is an important underlying mechanism in the decreased Na+-dependent D-glucose uptake into anhydro-4-epitetracycline-treated brush-border membrane vesicles.

Animals↗