Biomedical subjects

T Ono

Publications and source records attributed to T Ono.

At least 919 records · Page 51Linked to original sources

PubMed1989

Gametocytogenesis induction in cultured Plasmodium falciparum and further development of the gametocytes to ookinetes in prolonged culture.

Gametocytogenesis induction medium (RPMI-FSC reactive medium), prepared with a mixture of the culture supernatant from anti-Plasmodium falciparum antibody-producing hybridoma cells and hybridoma cell lysate, consistently induced gametocytogenesis in cultured P. falciparum. Gametocytogenesis was induced in three strains (0662, FCB 1, and FCR-3) and one clone (R.FCR-3) as has previously been described in two other strains (Ono et al. 1986). Both caffeine (2 mM/ml) and calmodulin (5 micrograms/ml) enhanced the effects of RPMI-FSC reactive medium. Furthermore, gametocytes that appeared after treatment with RPMI-FSC reactive medium continued their development to ookinete formation in candle jar culture with Waymouth's medium.

Animals↗

PubMed1989

A case of the pathogenesis of choledochocele in relation to dysfunction of the sphincter of Oddi.

A 47-year-old woman was admitted for evaluation of pain in the right upper quadrant of the abdomen. Seventeen years previously, she had undergone cholecystectomy for cholelithiasis. Endoscopic retrograde cholangiopancreatography (ERCP) showed a cystic dilatation of the terminal portion of the common bile duct (CBD) protruding into the duodenal lumen and delaying the drainage of contrast medium. In this patient the CBD and the pancreatic duct appeared to be unimportant in the formation of the cyst. Repeated changes in the radius of the cyst suggested dysfunction of the ampullary component of the sphincter of Oddi, with maintenance of normal function of the common duct component. The pathogenesis of the choledochocele in this patient is discussed in relation to dysfunction of the sphincter of Oddi. In addition, 2 criteria for the diagnosis of choledochocele by ERCP are proposed: [1] cystic dilatation of the terminal portion of the CBD protruding into the duodenal lumen, and [2] absence of the narrow segment of the CBD.

Ampulla of Vater↗

PubMed1989

Roles of Ca2+ in O2 evolution in higher plant photosystem II: effects of replacement of Ca2+ site by other cations.

The properties of the S2 states formed in Ca2+-extracted, Sr2+-substituted, and Cd2+-substituted photosystem II (PSII) were comparatively studied by means of thermoluminescence (TL) and low temperature EPR spectroscopy. The following results were obtained: (i) Ca-extracted PSII showed neither EPR multiline nor g = 4.1 signals but showed an abnormal TL band with an upshifted peak temperature, which did not oscillate on excitation with two or more flashes. Addition of Ca2+ to the extracted PSII reversed most of these effects concomitant with marked restoration of O2 evolution, but the EPR g = 4.1 signal remained lost. (ii) Sr2+ substitution largely restored the g = 4.1 signal and partly restored the multiline signal in a modified form having a reduced hyperfine line spacing concomitant with partial restoration of O2 evolution. Sr2+ substitution also reversed the abnormal TL peak temperature to normal, but the oscillation of the restored TL peak was much damped. (iii) Cd2+ substitution restored neither of the two EPR signals nor O2 evolution but reversed the abnormal TL peak temperature to normal. However, the reversed TL peak did not show any oscillatory behavior. Given these results, the function of the weakly bound Ca2+ in S-state turnovers in higher plant PSII is discussed.

Cadmium↗

PubMed1989

Suppression of atherogenesis in cholesterol-fed rabbits treated with nilvadipine, a new vasoselective calcium entry blocker.

We examined the effects of nilvadipine, a new dihydropyridine calcium entry blocker, on atherogenesis in rabbits fed a 1% cholesterol diet. The drug was given subcutaneously to the animals in hypotensive doses of 1.0 or 3.2 mg/kg/day for 10 weeks, and was well tolerated. Plasma total cholesterol increased markedly in all the cholesterol-fed rabbits, and nilvadipine had no effect on this, or on HDL-cholesterol and triglyceride levels. However, the area of Sudan IV positive intimal lesions (one of the parameters of atherosclerosis) in the aorta decreased significantly in the nilvadipine treated animals, and in addition, cholesterol and calcium content in the thoracic aorta were reduced. The reference drugs, nifedipine and nicardipine given subcutaneously in doses of 10.0 mg/kg/day either had no effect or were weaker in antiatherogenic effect than nilvadipine. The findings suggest that nilvadipine has more potent antiatherogenic activity than nicardipine or nifedipine.

Animals↗

PubMed1989

Muscular dystrophy-like disease in a thoroughbred foal.

A 1-month-old male thoroughbred foal, which had difficulty in walking, was killed and examined by histological, histochemical and ultrastructural methods. The muscles of the trunk and upper hind limbs were chiefly affected, and changes in the affected muscles resembled those in muscular dystrophy in man. The type of muscular dystrophy present in this foal and the significance of this disease in thoroughbred horses are discussed. The dystrophy in this foal resembled the limb-girdle type or myotonic dystrophy of muscular dystrophy in man.

Adenosine Triphosphatases↗

PubMed1989

Contribution of amygdalar and lateral hypothalamic neurons to visual information processing of food and nonfood in monkey.

Visual information processing was investigated in the inferotemporal cortical (ITCx)-amygdalar (AM)-lateral hypothalamic (LHA) axis which contributes to food-nonfood discrimination. Neuronal activity was recorded from monkey AM and LHA during discrimination of sensory stimuli including sight of food or nonfood. The task had four phases: control, visual, bar press, and ingestion. Of 710 AM neurons tested, 220 (31.0%) responded during visual phase: 48 to only visual stimulation, 13 (1.9%) to visual plus oral sensory stimulation, 142 (20.0%) to multimodal stimulation and 17 (2.4%) to one affectively significant item. Of 669 LHA neurons tested, 106 (15.8%) responded in the visual phase. Of 80 visual-related neurons tested systematically, 33 (41.2%) responded selectively to the sight of any object predicting the availability of reward, and 47 (58.8%) responded nondifferentially to both food and nonfood. Many of AM neuron responses were graded according to the degree of affective significance of sensory stimuli (sensory-affective association), but responses of LHA food responsive neurons did not depend on the kind of reward indicated by the sensory stimuli (stimulus-reinforcement association). Some AM and LHA food responses were modulated by extinction or reversal. Dynamic information processing in ITCx-AM-LHA axis was investigated by reversible deficits of bilateral ITCx or AM by cooling. ITCx cooling suppressed discrimination by vision responding AM neurons (8/17). AM cooling suppressed LHA responses to food (9/22). We suggest deep AM-LHA involvement in food-nonfood discrimination based on AM sensory-affective association and LHA stimulus-reinforcement association.

Affect↗

PubMed1989

Endogenous virus genomes become hypomethylated tissue--specifically during aging process of C57BL mice.

In an attempt to find out a cause for age-dependent derepression of endogenous viruses, extents of DNA methylation at the endogenous B- and C-type ecotropic viruses in brain, liver and spleen of C57BL/6NJc1 were examined at three ages, newborn, young adult and old. Both endogenous viruses showed a slight but significant tissue-specific either hypo- or hypermethylation during post-natal developmental phase in the three tissues. After maturation, however, no such change was detectable at most of the sites examined. The exceptions were C-type ecotropic virus in brain and B-type virus in spleen, where the age-dependent decreases of methylation were observed. The changes seemed to be continuations of preceding developmental hypomethylation. They indicated that the hypomethylation could be one of the causes for the age-dependent derepression of endogenous virus. It was further suggested that a mechanism to stop the developmental changes of DNA methylation at the maturation of individuals would be important in considering the reasons for the changes in senescent phase.

Aging↗

PubMed1989

Micronucleus test with vincristine administered by intraperitoneal injection and oral gavage.

The effects of vincristine sulfate (VINC) on micronucleus induction were studied in 2 strains of mice (MS/Ae: CD-1) following intraperitoneal (i.p.) or oral administration (p.o.) of the chemical. On the basis of a small-scale acute toxicity study and a pilot micronucleus experiment, the full-scale micronucleus test was performed with a sampling time of 24 h at doses of 0.063, 0.125, 0.25 and 0.5 mg/kg (i.p.) and 1.25, 2.5, 5.0 and 10 mg/kg (p.o.). The maximum frequency of micronucleated polychromatic erythrocytes was 7.15% in MS/Ae mice and 4.98% in CD-1 mice at 5.0 mg/kg p.o. in both cases. The maximum frequencies by the i.p. route (9.93% in MS/Ae mice; 11.68% in CD-1 mice) occurred at 0.25 mg/kg and 0.125 mg/kg, respectively. Although the doses showing a positive response were different between the 2 routes, VINC induced micronuclei very efficiently at all doses tested by both administration routes in both strains.

Administration, Oral↗

PubMed1989

The effects of hemorrhagic shock on thyrotropin-releasing hormone and its receptors in discrete regions of rat brain.

The effects of hemorrhagic shock on thyrotropin-releasing hormone (TRH) levels and its receptors were studied in different regions of the rat brain. Rats were bled for 30 min from the left femoral artery, and their mean arterial pressure was kept at 40 mmHg for the following hour. The rats were killed by decapitation. Rat brains were immediately removed and dissected into 7 regions. Hemorrhagic shock decreased TRH significantly in the frontal cortex, septum, hippocampus, and hindbrain but TRH was not changed in the striatum, hypothalamus, and midbrain. Hemorrhagic shock significantly decreased TRH receptor binding in the septum and hindbrain. Scatchard analysis of saturation isotherms of specific TRH binding showed that the decreased specific TRH binding in the hindbrain resulted not from an increase of the dissociation constant (Kd), but from a decrease in the maximum number of binding sites (Bmax). In the septum, the decrease in specific binding was due both to a decrease in Bmax and an increase in Kd. The findings indicate that TRH plays a role in the physiological response to hemorrhagic shock.

Animals↗

PubMed1989

Age-associated changes in DNA methylation and mRNA level of the c-myc gene in spleen and liver of mice.

Age-associated changes in DNA structure and mRNA level were studied for the c-myc gene in spleen and liver of mice at 2, 14 and 26 months of age. Neither amplification nor rearrangement of the gene was detected in either tissue at any age. However, a significant alteration was observed in the methylation profile. The profile of the gene and its vicinity was determined using various methylation-sensitive restriction enzymes. In both tissues, the gene had an unmethylated domain ranging from -2 kb upstream of the 5' end of the first exon to the 3' end of the first intron. It was flanked by partially methylated regions, where age-dependent changes as well as tissue specificity were observed. In the spleen, age-related hypomethylation was observed at both the 3' and 5' sides of the domain. In contrast, hypermethylation was found in the liver only at the 3' side. The steady-state level of c-myc mRNA showed a drastic decrease in liver from youth to middle age, while splenic mRNA changed little. The correlation between the changes of mRNA and DNA methylation is discussed.

Aging↗

PubMed1989

Evaluation of the pleural malignant mesothelioma patients with the relation of asbestos exposure.

There has been a recent increase in the number of patients with malignant mesothelioma in parts of Japan where Naval shipyards were located during World War II. This can be attributed to asbestos exposure during work in the shipyard. We have studied eight patients who were seen between 1984 and 1986 in Kure Kyosai Hospital. All had a history of asbestos exposure, seven in a Naval shipyard. In these seven cases, the latent period between exposure and the appearance of mesothelioma was 43-49 years. Quantification of asbestos bodies in the lung indicated a high concentration in all patients, giving further weight to the concept that asbestos is an etiologic factor in the genesis of mesothelioma. The major types of asbestos fibers were crocidolite and amosite. The study of structural features of these two types may provide a clue to the pathogenesis of the disease.

Aged↗

PubMed1989

Drosophila ninaA gene encodes an eye-specific cyclophilin (cyclosporine A binding protein).

Mutations in the ninaA gene of Drosophila severely reduce the amount of rhodopsin specifically in R1-6 photoreceptors. Isolation of the ninaA gene by chromosomal walking revealed that it is expressed only in the eye and encodes a 237-amino acid polypeptide that shows strong sequence similarity to cyclophilin, a putative molecular target for cyclosporine A, a potent immunosuppressant used in human organ transplantations. Unlike most cyclophilins characterized to date, the ninaA-encoded protein has a putative signal sequence and a transmembrane domain. Each of the three ehtyl methanesulfonate-induced ninaA mutant alleles analyzed shows a single nucleotide change in the mRNA coding region leading to either a nonsense or a missense mutation. We find no evidence that the ninaA-encoded protein is directly involved in phototransduction. The only detectable mutant phenotype that correlates with the severity of molecular defects in the three mutants is the amount of depletion of R1-6 rhodopsin. The above results and the recent findings that cyclophilin is a peptidylprolyl cis-trans-isomerase suggest that the ninaA-encoded protein may be required for proper folding and stability of R1-6 rhodopsin.

Amino Acid Sequence↗

PubMed1989

Promotional effect of lithocholic acid and 3-hydroxyanthranilic acid on transformation of X-ray-initiated BALB/3T3 cells.

X-ray-irradiated BALB/3T3 A31-1-1 cloned cells were post-treated with lithocholic acid (LCA), one of the bile acids, and 3-hydroxyanthranilic acid (3HOA), a tryptophan metabolite, in order to examine their potential to promote cell transformation. Insulin was added to the medium so as to increase the sensitivity of the cells to transformation. A dose-dependent increase in the number of transformed foci was observed with LCA. 3HOA had a very weak, though significant, activity. Transformation frequency was increased only a little, if any, by the treatment with cholic acid, which is structurally related to LCA. Anthranilic acid, an analogue of 3HOA, had no such effect. The results are discussed in view of the importance of endogenous promoters.

3-Hydroxyanthranilic Acid↗

PubMed1989

Covalent structure of a low-molecular-mass protein, meleagrin, present in a turkey (Meleagris gallopavo) ovomucoid preparation.

A low-molecular-mass protein, tentatively named meleagrin, was isolated from a commercial preparation of turkey (Meleagris gallopavo) ovomucoid. This 40-amino acid protein contains 3 disulfide bonds and high concentrations of aromatic residues (2 tryptophans and 3 tyrosines). It lacks threonine, methionine, phenylalanine, and arginine residues. The complete amino acid sequence was determined to be the following: less than Glu-Val-Leu-Lys-Tyr-Cys-Pro-Lys-Ile-Gly-Tyr-Cys-Ser-Ser-Lys-Cys-Ser-Lys- Ala- Glu-Val-Trp-Ala-Tyr-Ser-Pro-Asp-Cys-Lys-Val-His-Cys-Cys-Val-Pro-Ala-Asn- Gln-Lys - Trp. One of the three disulfide bonds exists between Cys12 and Cys28, and the two others links Cys32-Cys33 with Cys6 and Cys16. The amino acid sequence of meleagrin shows a strong homology to a similar basic protein, cygnin (Simpson, G.R. & Morgan, F.J. [1983] Int. J. Pep. Protein Res. 22, 476-481), of a rather distantly related aves, black swan (Cygnus atratus), suggesting some vital role of this protein in avian eggs. Similarity to a part (exon 9) of transferrins was also recognized.

Amino Acid Sequence↗

PubMed1989

Evaluation of fluorescence polarization immunoassay for determination of cyclosporin in plasma.

The fluorescence polarization immunoassay (FPIA) method for determination of cyclosporin in plasma was evaluated and compared with the high-performance liquid chromatography (HPLC) and the radioimmunoassay (RIA) methods. The coefficients of variation for the within-run and between-run precision were less than 5 and less than 8%, respectively, for samples ranging in concentration from 50 to 600 ng/ml. Recoveries were determined by adding cyclosporin at concentrations from 25 to 1,000 ng/ml to patient plasma; they were, on average, 98.5%. The calibration curve was stable throughout a 10-week study period. There was no clinically significant interference due to hemolysis, icterus, lipemia, or other commonly used drugs. There was considerable variation of the ratio of the FPIA result to the HPLC result, whereas there was a good correlation between the FPIA and the RIA results (r = 0.975, n = 25, y = 1.2x - 36.4), when evaluated using specimens from renal transplant patients receiving cyclosporin orally. It was concluded that the FPIA is an appropriate, rapid method for patient cyclosporin analysis in plasma and serves as a practical alternative to the RIA.

Adolescent↗

PubMed1989

Proliferating giant pigmented nevus: a report of an unusual tumor occurring in association with a congenital giant pigmented nevus.

A 32-year-old Japanese woman with a giant pigmented congenital nevus of the torso presented with a massive pigmented tumor mass of the vulva which grew over an 8-year period. Histologically, the tumor was composed of benign appearing nevus-like cells with focal areas of extensive fibrous response. The tumor cells were positive for S-100 protein and with an antihuman melanoma antibody (MoAb 225, 28S) stain. Electron microscopy confirmed the nevomelanocytic nature of the tumor cells and demonstrated peculiar cytoplasmic crystalline tubular structures similar to those seen in cells infected with herpes virus type II. We propose the term "proliferating giant pigmented nevus" for this previous undescribed tumor.

Adult↗

PubMed1989

Morphea profunda--a cutaneo-pulmonary variant with profuse sweating.

A 51-year-old Japanese male developed morphea profunda over a plaque of pigmented sweating skin on the left chest extending deeply into the lung. Eight years previously, he noted a brown pigmented spot on the left axilla which started to enlarge over the left chest in a band-like manner. Later, the involved skin hardened with profuse sweating. Chest X-ray examination and computer tomography revealed a thickening of the left chest wall and a nodular mass lesion in the left lower lung field. Biopsy specimens from lung, chest wall, and overlying skin revealed a granulomatous tissue in the parenchyma and a marked fibrosis extending from the deep dermis to the pleura. There were no findings suggestive of malignancy or chronic infectious disease. We assume that the process of morphea in this patient extended deeply from the skin to the lung.

Humans↗

PubMed1989

Pigmented basal cell carcinoma developing on the lower extremities--three cases masquerading as malignant melanoma.

Three cases of pigmented basal cell carcinoma were reported which needed to be differentiated from malignant melanoma based on their location and clinical features. Clinicopathologically, they were characterized by a large number of melanophages in the stroma, blockade melanocytes in the parenchyma, and phagocytosis of melanosomes in tumor cells as well as a large number of intraparenchymal melanophages. Two cases were characterized by the aggregation of melanophages in cystic spaces caused by stellate atrophy.

Aged↗