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Biomedical subjects

A Ohara

Publications and source records attributed to A Ohara.

At least 91 records · Page 5Linked to original sources
PubMed1990

Relationship between gastric mucosal prostaglandin levels and healing of gastric lesions in rats.

1. This study was designed to determine whether or not endogenous prostaglandins (PG) contribute to the healing of gastric ulcers induced by high concentrations of ethanol or water immersion stress. 2. Ethanol-induced gastric lesions; rats were divided into four groups: (1) the control group: untreated; (2) the indomethacin group: indomethacin (2 mg/kg) was injected intramuscularly (i.m.) once daily until the end of the experiment; (3) the ethanol group: rats were given 1 mL of 50% ethanol intragastrically; (4) the ethanol + indomethacin group: indomethacin (2 mg/kg) was injected (i.m.) once daily from 1 h after administration of 50% ethanol until the end of the experiment. 3. Water immersion stress-induced gastric lesions; rats were divided into three groups: (1) control group: untreated; (2) stress group: rats were placed in a stress cage and immersed into a water bath (23 degrees C) for 6 h; (3) stress + indomethacin group: indomethacin (2 mg/kg) was injected (i.m.) once daily for 3 consecutive days immediately after stress treatment or from 3 days after stress treatment until the end of the experiment. 4. Immediately after observation of the lesions, the fundic mucosal layer was separated from the muscle layer and mucosal PG levels were measured by high performance liquid chromatography in each group. 5. Indomethacin did not inhibit ulcer healing until 48 h after administration in the ethanol experiment, and until 3 days after administration in the water immersion experiment. In contrast, indomethacin inhibited ulcer healing thereafter in each experiment respectively. 6. Four kinds of PG, that is 6-keto-PGF1 alpha, PGF2 alpha, PGE2 and PGD2 were detected in gastric mucosa.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

Tyrosine formation from phenylalanine by ultraviolet irradiation.

When phenylalanine was irradiated at ultraviolet (UV) light, p-tyrosine, m-tyrosine and o-tyrosine were identified as hydroxylated products. From p-tyrosine and m-tyrosine, the formation of L-3,4-dihydroxyphenylalanine (DOPA) was observed. The hydroxylation of phenylalanine was prevented by radical scavengers, e.g., catalase, superoxide dismutase, sodium thiocyanate, mannitol, potassium iodide and thiourea. Replacement of air with nitrogen gas prevented the hydroxylation, but did not depress it completely. The addition of H2O2 increased significantly the hydroxylation of phenylalanine. These results suggest that the hydroxylation of phenylalanine by UV irradiation may be caused by .OH formed during the decomposition of H2O.

Hydroxylation↗
PubMed1990

Accelerating effect of glutathione on hydroxylation of phenylalanine by stimulated polymorphonuclear leukocytes.

Sulfhydryl compounds significantly accelerated the hydroxylation of phenylalanine by stimulated polymorphonuclear leukocytes. The reduced form of glutathione (G-SH) was most effective. The hydroxylation reaction in the presence of G-SH was largely prevented by superoxide dismutase and hydroxyl radical scavengers. The results suggest that a much faster production of hydroxyl radical may occur in a reaction mixture containing both G-SH and stimulated polymorphonuclear leukocytes than in that containing stimulated polymorphonuclear leukocytes alone.

Animals↗
PubMed1990

Fibronectin receptor on polymorphonuclear leukocytes in families of Ehlers-Danlos syndrome and other hereditary connective tissue diseases.

Studies were made on the fibronectin receptor on polymorphonuclear leukocytes of patients with hereditary connective tissue diseases and of healthy members of their families. In four patients with Ehlers-Danlos syndrome type II (family E) and type VI (family M), the maximum number of binding sites (Bmax) of fibronectin receptor was significantly decreased to 2.2 to 2.9 x 10(3) sites/cell (normal range 6.3 +/- 1.5 x 10(3) sites/cell). The Bmax values of healthy members of their families were normal or moderately decreased to 3.8 to 5.1 x 10(3) sites/cell. In a patient with osteogenesis imperfecta type III (family K) the Bmax was significantly decreased to 1.1 x 10(3) sites/cell, but healthy members of his family had normal Bmax values. In a patient with Marfan syndrome (family A) the Bmax was decreased to 4.3 x 10(3) sites/cell. The dissociation constant of the fibronectin receptor was normal in all subjects examined. Some healthy members of the families of the patients with Ehlers-Danlos syndrome had moderately decreased Bmax values, suggesting that they are carriers of an abnormal gene causing this disorder. These data suggest that fibronectin receptor is closely related to the pathogenesis of hereditary connective tissue diseases.

Adult↗
PubMed1990

[Endoscopic ultrasonography for assessing the horizontal spread of invasive gastric cancer].

The subjects were 64 cases of gastric cancer. In all 64 cases, resected specimens (formalin fixed) were subjected to endoscopic ultrasonographic examination by the water immersion method in order to assess the horizontal spread of the invasive gastric cancer. Ultrasonographic findings were compared with the histopathological findings of resected specimens. The tumor which invaded the submucosa or deeper layers was visualized as low echogenicity region in the third layer (corresponding to the submucosa) or deeper layers. The horizontal spread of the low echogenicity region represented that of the tumor or the associated fibrosis, but not the tumor itself. In the cases showing echo patterns which were characteristic of the peptic ulceration in the tumor focus (Type II-1, II-2, UL), the horizontal spread of cancer invasion in the submucosal layer or deeper layers (L Ca) was smaller than that of low echogenicity region depicted by ultrasonography (L U). In the other (Type II-3, III, A, B) cases, L Ca was almost comparable to L U.

Gastric Mucosa↗
PubMed1990

Quantitative determination of prostaglandin levels in human gastric mucosa--analysis by microcolumn high performance liquid chromatography with laser induced fluorescence detection.

This study was designed to analyze PGs in human gastric mucosa using biopsy specimens at femtomole level by the combination of microcolumn HPLC and He/Cd laser induced fluorescence detection. Biopsy specimens were taken along the greater curvature at the corpus of the stomach, in which no gastric disease was revealed by endoscopic examination. PGs extracted from human gastric mucosa were derivatized with ADAM, and ADAM-derivatized PGs were injected into the column for analysis. The mobile phase of acetonitrile-water (73:27) containing 0.01% of phosphoric acid was used at a constant pressure of 20 kgf/cm2. Using this system, PGs in few mg of human gastric mucosa obtained by biopsy were well separated and detected; i.e., 1653 +/- 254 (femtomole/mg tissue), 279 +/- 56, 729 +/- 153, 831 +/- 199 for 6-keto-PGF1 alpha, PGF2 alpha, PGE2, and PGD2, respectively. In conclusion, the microcolumn HPLC system with laser induced fluorescence detection is a reliable method for determining individual PGs in human gastric mucosa. In addition, PGI2 is the predominant PG in human gastric mucosa and probably plays an important role in gastric function.

6-Ketoprostaglandin F1 alpha↗
PubMed1989

Improved hematopoiesis in anemic Sl/Sld mice by splenectomy and therapeutic transplantation of a hematopoietic microenvironment.

The ability of a clonal hematopoiesis-supportive bone-marrow stromal cell line GBlneor to engraft and alter the microenvironment-induced anemia of Sl/Sld mice was studied. Prior to stromal cell transplantation, Sl/Sld mice received 1 Gy total body irradiation (TBI) and 13 Gy to the right hind limb. Two months after intravenous (IV) injection of 5 x 10(5) GBlneor cells, 54.4% +/- 17.0% donor origin (G418r) colony-forming cells were recovered from the right hind limb of Sl/Sld mice. Long-term bone marrow cultures (LTBMCs) established from GBlneor-transplanted mice produced 189.5 CFU-GEMM-forming progenitors/flask over 10 weeks compared with 52.7 +/- 6.2 CFU-GEMM forming progenitors/flask from irradiated nontransplanted Sl/Sld mice. A partial correction of macrocytic anemia was detected 2 months after GBlneor transplantation in splenectomized, irradiated Sl/Sld mice (HgB 7.2 +/- 0.4 g/dL; MCV 68.3 +/- 7.0 fL) compared to splenectomized, irradiated, nontransplanted Sl/Sld mice (HgB 5.5 +/- 1.1 g/dL; MCV 76 +/- 8.5 fL) or control Sl/Sld mice (HgB 5.4 +/- 0.5 g/dL; MCV 82.4 +/- 1.3 fL). Mean RBC volume distribution analysis showed a 2.5-fold increase in percentage of peripheral blood RBCs with MCV less than or equal to 45 fL and confirmed reduction of the MCV in splenectomized-GBlneor-transplanted mice compared to control Sl/Sld mice. A hematopoiesis-suppressive clonal stromal cell line derived from LTBMCs of Sl/Sld mice (Sldneor) engrafted as effectively (43.5% +/- 1.2% G418r CFU-F/limb) as did GBlneor cells (38.3% +/- 0.16% G418r CFU-F/limb) to the irradiated right hind limbs of C57Bl/6 mice. LTBMCs established after 2 or 6 months from Sldneor-transplanted mice showed decreased hematopoiesis (182 +/- 12 [2 months] and 3494.3 +/- 408.1 [6 months] CFU-GEMM forming progenitors/flask over 10 weeks) compared to those established from GBlneor-transplanted mice (5980 +/- 530 [2 months] and 7728 +/- 607, [6 months] CFU-GEMM progenitors forming/flask). Thus, transplantation of clonal bone-marrow stromal cell lines in vivo can stably transfer their physiologic properties to normal or mutant mice.

Anemia↗
PubMed1989

Recombinant murine GM-CSF increases resistance of some factor dependent hematopoietic progenitor cells to low-dose-rate gamma irradiation.

The effects of murine recombinant IL-3 (multi-CSF) and murine recombinant GM-CSF (granulocyte-macrophage colony stimulating factor) on the radiation biology of clonal hematopoietic progenitor cell lines were evaluated. Four clonal cell lines with growth response to either IL-3 or GM-CSF (FDCP-1JL26, and bg/bg d64) or exclusively dependent on IL-3 (32D cl 3 and B6SUtA), were pre-incubated in IL-3, or GM-CSF, for 7 days prior to gamma irradiation, then washed and irradiated at 5 cGy/min, or 116 cGy/min, and transferred to semisolid medium supplemented with either IL-3, or GM-CSF, for assay of 7 day greater than or equal to 50 cell colonies. The cell lines demonstrated similar radiosensitivity and lack of a detectable dose-rate effect when grown in IL-3 (FDCP-1JL26: D0 154, n 1.05 at 5 cGy/min, and D0 138, n 1.16 at 116 cGy/min; bg/bg d64: D0 95.7, n 1.16 at 5 cGy/min, and D0 97.7 n .993 at 116 cGy/min; B6SUtA: D0 101, n 1.29 at 5 cGy/min, D0 100, n 1.27 at 116 cGy/min; and cell line 32D cl 3: D0 123, n 1.65 at 5 cGy/min, and D0 126, n 1.17 at 116 cGy/min). In contrast, FDCP-1JL26 cells demonstrated a significant relative radioresistance at low-dose-rate when grown in recombinant GM-CSF, (D0 217, n 1.27 at 5 cGy/min, D0 138, n 1.34 at 116 cGy/min, p less than .005). The increase in radioresistance of FDCP-1 cells at low-dose-rate was induced either by preincubation in GM-CSF with transfer to IL-3, or by preincubation in IL-3 and transfer to recombinant GM-CSF. Growth factor independent malignant subclones of lines B6SUtA and FDCP-1JL26 demonstrated a significant increase in radioresistance at low-dose-rate (B6SUtA EL4JL: D0 187, n 1.39 at 5 cGy/min, and D0 133, n 1.73 at 116 cGy/min (p. less than .05); and FDCP-1JL26 F7 cl 2: D0 191, n 1.17 at 5 cGy/min, and D0 150, n 1.31 at 116 cGy/min [p less than .05]). Thus, some hematopoietic progenitor cell lines are induced by GM-CSF to grow after irradiation at low-dose-rate similar to the growth of clonal malignant cell lines. The data may have implications for the radiation biology of normal hematopoietic progenitor cells in two circumstances: (a) selective survival of GM-CSF responsive cells after total body irradiation, and (b) selective survival of some hematopoietic progenitors in vivo during clinical recombinant GM-CSF infusion.

Animals↗
PubMed1989

[Comparative clinical study of roxithromycin and josamycin for suppurative skin and soft tissue infections by a double-blind method].

The clinical efficacy and safety of Roxithromycin (RU 28965, RU), a new macrolide preparation, were compared with those of Josamycin (JM) in superficial suppurative skin infections. The study was designed as double-blind controlled trial with daily dosages of 300 mg in RU group and 1200 mg in JM group. A total of 209 cases (RU:105; JM:104) was analyzed and the final global improvement rating was 82.9% in the RU group and 80.8% in the JM group; there was no significant difference between the two groups. Slight adverse reactions were observed in 3.6% (4 cases) of the RU group and in 4.6% (5 cases) of the JM group. In conclusion, RU at daily doses of 300 mg is as effective as JM at daily doses of 1200 mg in superficial suppurative skin infections.

Adult↗
PubMed1989

Stimulatory effects of purified human follicle-stimulating hormone on estradiol production in the human luteal phase.

A bolus iv injection of 150 IU purified human urinary FSH (hFSH) or saline was given to 21 normal women during 3 different luteal phases (early luteal phase, n = 7; midluteal, n = 8; late luteal, n = 6), and the responses of ovarian steroids and gonadotropins were analyzed sequentially for 24 h after hFSH injection. A rapid and dramatic increase in serum FSH concentrations occurred after each hFSH injection, followed by a gradual decrease. Serum LH concentrations, including hourly fluctuations, were significantly higher after FSH administration than after NaCl injection at the same time during the preceding cycle. Neither serum progesterone nor testosterone levels were affected by the hFSH injection in any of the 3 luteal phases, but in the early and midluteal phases serum estradiol levels were higher than the preinjection values and those during the control cycles. These results indicate that FSH stimulates aromatization of luteal tissue in vivo as it does in vitro. Thus, FSH in addition to LH as the indispensable luteotropin may have a permissive role in the regulation of corpus luteum function.

Adult↗
PubMed1989

Long-term prognosis and residual abnormalities of idiopathic acquired aplastic anemia in children.

We evaluated the long-term prognosis and quality of cure of idiopathic acquired aplastic anemia in children. Of the 244 patients registered from 1965 to 1985, those registered in 1965-1975 and 1976-1985 had a survival rate of 50.1% and 62.0%. The percentage of cure, undertreatment and death was 30, 30 and 40%, respectively. About 40% of the patients with moderate cases, died dead or required frequent blood transfusions. In the case of pediatric patients, as the success rate of bone marrow transplantation was high. This modality should be considered for patients with moderate severity who require blood transfusion 3 months after the diagnosis and an HLA identical donor is available. Physical development was almost normal but 35% of the patients showed residual abnormalities such as bleeding tendency, and hepatic disorders due to treatment. Thrombocytopenia and ineffective hematopoiesis were observed in one-third of the patients and all of the patients showed abnormal committed stem cell assay. The CD 4/8 ratio was reduced in 50% of the patients and 15% exhibited psychological problems. These residual abnormalities last for years, and sometimes a lifetime.

Anemia, Aplastic↗
PubMed1989

[Diagnosis of paraaortic and pelvic lymph node metastasis by ultrasound guided percutaneous fine needle aspiration biopsy (FNAB)].

Ultrasonography (US) was performed in patients with gynecologic malignancies to detect paraaortic and pelvic lymphadenopathy. US of paraaortic lymph nodes was performed in 32 patients. Of the 32 patients 17 had lymphadenopathy, and ultrasound-guided percutaneous fine needle aspiration biopsies (FNAB) were therefore performed in 16 of these 17 cases. Of these 16 patients, 11 were positive and 5 were negative FNAB. US of pelvic lymph nodes was performed in 68 patients. Of the 68 patients 14 had lymphadenopathy, and FNAB were performed in 8 of these. All 14 of these FNABs were positive. There were no major complications from due to FNAB. It is therefore concluded that ultrasound-guided percutaneous FNAB is very useful in detecting metastatic lymph nodes of gynecologic malignancies.

Aorta, Abdominal↗
PubMed1989

Retroviral src gene expression in continuous marrow culture increases the self-renewal capacity of multilineage hematopoietic stem cells.

To define the action of the retroviral src gene on hematopoietic stem cells, C57BL/6 x DBA/2 (B6D2F1) mouse long-term marrow cultures were infected at initiation with Moloney murine leukemia virus (MuLV) pseudotypes of src-recombinant retroviruses with the src gene inserted in the env region of an amphotropic MuLV (src-Ampho), or in the gag region of Moloney MuLV (src-Mo). Other cultures were infected with Friend spleen focus-forming virus polycythemia-inducing strain (SFFVp), Moloney MuLV, or amphotropic MuLV, or were uninfected controls. Harvested nonadherent cells were tested weekly for multilineage, granulocyte-erythroid-megakaryocyte macrophage (CFU-GEMM) colony formation in vitro in recombinant murine IL-3 and erythropoietin, and individual colonies were removed, split 1:2, with half of each replated for in vitro self-renewal and the other half examined morphologically for number of hematopoietic cellular lineages, or tested for release of MuLV and src virus. Cultures infected with src-Ampho, src-Mo, or SFFVp demonstrated a significant increase in cumulative nonadherent cell and CFU-GEMM production. There was prolonged self-renewal over seven serial transfers of individual CFU-GEMM from src virus-infected cultures over seven serial transfers, and five of 61 individual colonies from the second or third generations contained detectable v-src gene sequences, but none released detectable src virus. Self-renewal of CFU-GEMM was similar to that with permanent IL-3-dependent cell line B6SUtA. In contrast, MuLV-infected or control uninfected cultures produced fewer cells, and self-renewal of CFU-GEMM did not exceed three generations. IL-3-dependent clonal hematopoietic progenitor cell lines, derived from each culture group, formed no detectable tumors in vivo; however, each released the original helper and/or transforming virus. Adherent cell lines, derived from src-Ampho-infected cultures released src virus and formed fibro-sarcomas in vivo. The data support the conclusion that src-recombinant virus expression in long-term marrow cultures increases the self-renewal capacity of multilineage hematopoietic stem cells.

Animals↗
PubMed1988

Na/K pump activity in the new membrane formed at first cleavage in Cynops pyrrhogaster eggs.

Resting membrane potentials (Em) increased in the negative direction during first cleavage in Cynops pyrrhogaster eggs whose new membranes formed at first cleavage were exposed to bathing solutions by removing the vitelline envelopes. Em was -11.4 and -87.2 mV at the one- and two-cell stages, respectively. Na/K pump activity contributed to Em at the two-cell stage by about -30 mV. The distribution of Na/K ATPase activity was cytochemically studied by Ernst's method (S. A. Ernst, 1972, J. Histochem. Cytochem. 20, 23-38). The new membrane of the eggs at the two-cell stage showed the pump activity. But the activity was detected neither in the preexisting outer membrane of the eggs at the two-cell stage nor in the membrane at the one-cell stage.

Animals↗
PubMed1988

Mutagen formed from tryptophan reacted with sodium nitrite in acidic solution.

The reaction products from L-tryptophan treated with nitrite under acidic conditions were investigated for mutagenic activity with the Salmonella typhimurium his reversion assay and for DNA-damaging activity using the rec-assay. The diethyl ether extract of the reaction mixture showed 8 spots on thin-layer chromatography (TLC). One compound from the TLC had high mutagenic activity for TA98 without S9 mix, with little DNA-damaging activity. The mutagen was purified and identified by instrumental analysis as 2-hydroxy-(1-N-nitrosoindole)propionic acid (NIHP). The mutagenic activity of NIHP was determined by the induced mutation frequency method; the induced mutation frequency was about 19.2 X 10(-5) at a dose level of 160 micrograms/plate.

Acids↗