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H Ohtake

Publications and source records attributed to H Ohtake.

At least 91 records · Page 5Linked to original sources
PubMed1996

Molecular analysis of the phosphate-specific transport (pst) operon of Pseudomonas aeruginosa.

The organization of the phosphate-specific transport (pst) operon in Pseudomonas aeruginosa has been determined. The gene order of the pst operon is pstC, pstA, pstB, phoU, and a well-conserved Pho box sequence (16/18 bases identical) exists in the promoter region. The most striking difference from the known Escherichia coli pst operon is the lack of the pstS gene encoding a periplasmic phosphate (Pi)-binding protein. Even though the three pst genes were absolutely required for P(i)-specific transport, expression of the pst operon at high levels did not increase P(i) uptake in P. aeruginosa. DNA sequences for the pstB and phoU genes have been determined previously. The newly identified pstC and pstA genes encode possible integral membrane proteins of 677 amino acids (M(r) 73,844) and 513 amino acids (M(r) 56,394) respectively. The amino acid sequences of PstC and PstA predict that these proteins contain a long hydrophilic domain not seen in their E. coli counterparts. A chromosomal deletion of the entire pst operon rendered P. aeruginosa unable to repress P(i) taxis under conditions of P(i) excess. The phoU and pstB genes are essential for repressing P(i) taxis. However, mutants lacking either PstC or PstA alone were able to repress P(i) taxis under conditions of P(i) excess.

ATP-Binding Cassette Transporters↗
PubMed1996

Surgical therapy for Wolff-Parkinson-White syndrome in patients with bronchial asthma.

The surgical therapy for Wolff-Parkinson-White syndrome in patients with bronchial asthma was studied. Between 1974 and 1992, 447 patients with Wolff-Parkinson-White syndrome were treated, seven of whom had associated severe bronchial asthma. Supraventricular tachyarrhythmias were induced on occasion by bronchodilating agents such as beta-receptor agonists or theophylline preparations. High-dose steroids were required for acute bronchospasm in three patients, despite possibly leading to cardiac dysfunction. Beta-blockers therapy for Wolff-Parkinson-White syndrome can induce bronchospasm; in patients with Wolff-Parkinson-White syndrome and bronchial asthma, pharmacological agents used to treat one condition may exacerbate the other. Therefore, a non-pharmacological therapy was performed, namely surgical division of the accessory conduction pathway via an endocardial approach, in all seven asthmatic patients with Wolff-Parkinson- White syndrome. In all cases, division of the accessory conduction pathway resulted in disappearance of the delta wave, and there were no further tachyarrhythmias either at rest or after administration of bronchodilators. Since surgery, bronchial asthma has been effectively controlled with standard drug therapy in all patients. Non-pharmacological therapy is recommended for patients with Wolff-Parkinson-White syndrome and bronchial asthma.

Adolescent↗
PubMed1996

Eosinophil apoptosis caused by theophylline, glucocorticoids, and macrolides after stimulation with IL-5.

BACKGROUND: Glucocorticoids have long been used as the most potent drugs in the treatment of bronchial asthma. Data reported recently have led to the proposal that theophylline and macrolides have antiinflammatory effects. OBJECTIVE: We examined the abilities of theophylline, glucocorticoids, and macrolides to counteract the prolongation of eosinophil survival caused by IL-5. METHODS: Purified guinea pig eosinophils were cultured in the presence or absence of human IL-5 and with or without the aforementioned drugs at various concentrations. The percentage of cells alive after 3 days in culture was determined. RESULTS: Aminophylline (AM), methylprednisolone (MP), erythromycin (EM), and clarithromycin (CAM) suppressed the IL-5 induced prolongation of eosinophil survival in a dose-dependent manner. The effects of these drugs on eosinophil survival were significantly greater at low concentrations of IL-5 than at high concentrations of IL-5. When eosinophils were cultured in the presence of IL-5 (1 ng/ml) with physiologic concentrations of MP (10(-6) mol/L), AM (10(-4) mol/L), and either EM or CAM (both 10 micrograms/ml), the effect of IL-5 was almost completely abolished, and the morphologic changes in eosinophils observed by electron microscopy were consistent with apoptosis. DNA extracted from eosinophils cultured with IL-5 and each of the drugs was definitely fragmented. CONCLUSIONS: One mechanism of the effectiveness of these drugs is induction of eosinophil apoptosis. Some combination of these drugs may be useful in the treatment of bronchial asthma.

Aminophylline↗
PubMed1996

A new contact probe for intraoperative laser ablation.

Several clinical factors decrease the accuracy of intraoperative laser ablation. The distance to the target, the irradiation angle, and the media are reported among these factors. We developed a new laser probe to resolve these problems. This probe has a hollow conical tube with a tip covered by a thin film. Zero-degree centigrade saline was fed into this probe. Results from using the new probe were compared with those from the conventional noncontact irradiation method with cooling by sprinkled cooling water. In beating canine hearts, ventricles were irradiated with neodymium:yttrium aluminum garnet (Nd:YAG) lasers at 50-200 J/mm2. There was no difference in the mean volume of irradiated tissue between the new and the noncontact method. However, the distribution of volume values in the new method was smaller than that in the noncontact method (P < 0.05). In conclusion, results obtained indicate that this new probe could perform more accurate intraoperative ablation than the conventional method. Problems of stabilizing the distance to the target, the irradiation angle, and the media were resolved.

Animals↗
PubMed1996

Role of macrophages in ovarian follicular development.

The effects of macrophages on granulosa cell proliferation were examined using gonadotropin-primed immature female rats and osteopetrotic (op/op) mice, a model defective in monocyte-macrophage lineage cells. Macrophages were found in the follicles at various developmental stages in rats and mice. The labeling index with [3H]thymidine of cultured rat granulosa cells was maximal when they were cultured with peritoneal macrophages at a macrophages:granulosa cell ratio of 0.01. This ratio was similar to those in rat preantral and antral follicles in vivo. In op/op mice, the number of developing follicles was markedly reduced, but increased after daily macrophage-colony-stimulating factor (M-CSF) administration. In the antral follicles of op/op mice, both granulosa cells and macrophages were significantly decreased in number but were increased after M-CSF treatment. Double immunohistochemical staining revealed that epidermal growth factor (EGF)-positive cells were macrophages in the developing rat follicles. These findings suggest that macrophages are located in the developing follicles and participate in promoting granulosa cell growth through a paracrine mechanism by secreting EGF and other cytokines.

Animals↗
PubMed1996

Ontogenic changes in the expression of cytochrome c oxidase subunit I gene in the cerebellar cortex of the perinatal hypothyroid rat.

The thyroid hormone plays a critical role in normal development of the mammalian central nervous system. This study was designed to examine the effect of perinatal hypothyroidism on ontogenic change in cytochrome c oxidase subunit I (COX I) gene expression in the rat cerebellum by using quantitative in situ hybridization histochemistry (ISH). Newborn rats were rendered hypothyroid by continuous administration of methimazole in the mothers' drinking water. The pups were then killed by decapitation on 1, 5, 10, 15, 20, and 30 days after birth (P1, P5, P10, P15, P20, and P30). Their cerebella were removed, and frozen sections were cut and processed for ISH with 35S-labeled RNA probe for COX I messenger RNA. After hybridization, emulsion autoradiography was performed. The numbers of grains within the external granule cell layer, molecular layer, and internal granule cell layer were then counted. A significant decrease in grain density was detected in the hypothyroid animal in all these areas on P5, P10, and P15. On P15, in the molecular layer, a greater hybridization signal was detected in the inner portion than in the outer portion in the euthyroid animal. No such difference was seen in the hypothyroid animal. Daily T4 treatment for 15 days restored the effect of methimazole treatment. The significant effect of perinatal hypothyroidism on COX I gene expression was not detected after P20. These results indicate that altered thyroid states affect the COX I gene expression in the cerebellar cortex during development, suggesting that the COX I gene is one of the key genes regulated by the thyroid hormone and plays an important role in the morphogenetic changes observed in the perinatal hypothyroid cerebellum.

Aging↗
PubMed1996

Regional comparison of prolactin gene expression in the human decidualized endometrium in early and term pregnancy.

Prolactin (PRL) is known to be expressed in the decidualized human endometrium and secreted into amniotic fluid. Although the site of synthesis of endometrial PRL is known to be the decidual cells, the difference in PRL gene expression within each area of decidua, i.e. decidua basalis, decidua parietalis and decidua capsularis, during pregnancy is not clear. We have applied an in situ hybridization histochemistry technique using a radiolabeled RNA probe to compare the difference in expression of PRL gene within each area of the decidualized endometrium. Specific hybridization signals were distributed over the decidual cells in early and term pregnancy. More intense hybridization signals were always detected in the tissues of early pregnancy than in those of term pregnancy. In the decidua capsularis of early pregnancy, labeled cells were concentrated close to the amniotic cavity, whereas cells were concentrated close to the maternal surface of the fetal membrane in term pregnancy. In the decidua parietalis, almost all decidual cells were labeled, but no specific labeling was seen in the endometrial glands or capillary endothelium in both groups. In the decidua basalis, most decidual cells showed hybridization signals whereas no hybridization signal was seen over the trophoblast cells. These results show that there are regional and periodic differences in PRL gene expression in the decidual cells during pregnancy.

Decidua↗
PubMed1996

Twice sealed-rupture of a small abdominal aortic aneurysm with unusual computed tomography findings. A case report.

Small abdominal aortic aneurysm rupture is uncommon and fatal. We report a case of twice sealed-rupture small abdominal aneurysm 3.5 cm in diameter. Computed tomography showed unusual findings of a hematoma-like multiple cyst around the small aneurysm. We were bothered the diagnosis. By the intraoperative finding; an irregular pseudoaneurysm, the final diagnosis was performed. After aneurysmectomy, artificial graft replacement was made. From only this case, discussion of the indications for the small abdominal aortic aneurysm is difficult. However, the possibility of the rupture in even this [correction of thus] small abdominal aortic aneurysm should be considered.

Aged↗
PubMed1996

[Endovascular stenting for a recurrent angina patient].

We report successful Palmaz-Schatz stenting for recurrent angina. Coronary arteriography in a 65-year-old man with recurrent angina six months after coronary artery bypass grafting (CABG) showed stenosis in the right coronary artery and in the saphenous vein graft to the left anterior descending artery. For both stenotic lesions, balloon dilatation was performed. However, both lesions recoiled after dilatation. Therefore, Palmaz-Schatz stents were inserted in both stenotic lesions. After stenting, the patient did not experience any further chest pain. Three months later coronary arteriography showed the stents remained patient. Balloon angioplasty for post-CABG angina is technically easier than additional surgery. However, angioplasty by balloon dilatation alone can induce dangerous complications during the acute phase and restenosis frequently develops. This method is not sufficiently effective or safe for recurrent angina. To prevent these problems, the stent was developed as a useful adjunct to balloon dilatation for the native artery. Using this new device, angioplasty for recurrent angina will be safer and more effective than additional surgery.

Aged↗
PubMed1996

[A basic and clinical evaluation of a new immunoradiometric assay kit for human serum tissue polypeptide antigen (TPA)].

A new immunoradiometric assay kit (IRMA) of human serum tissue polypeptide antigen (TPA) based on combination monoclonal antibodies was evaluated. Using a new TPA-IRMA, the procedure of TPA measurement was faster and the range of measurement was more wide than a conventional TPA-IRMA. 89% (76/85 cases) of patients with malignant tumor and 96.4% (27/28) of patients with metastatic malignant tumor were positively detected. This assay of new TPA-M kit is sensitive to the level of serum TPA which is corresponding to a therapy. It is concluded that a new TPA-IRMA is very useful in monitoring and assessing malignant tumors.

Adult↗
PubMed1996

[Expression of prolactin receptor gene in human decidua of early pregnancy].

UNLABELLED: This study was designed to examine the expression of the prolactin receptor (PRL-R) gene in the human decidualized endometrium and to determine the localization of endometrial cells expressing the PRL-R gene. METHOD: Decidua and trophoblast tissues of normal and ectopic pregnancy were obtained by curettage from patients undergoing artificial abortion at 8 -10 weeks of gestation. Total RNA was extracted to perform northern blot hybridization with a radiolabeled human PRL-R cDNA probe. Some tissues were cut and processed for in situ hybridization histochemistry with a radiolabeled RNA probe. RESULTS: 1. Northern blot hybridization: Approximately 9.0, 3.6 and 2.8kb size bands were detected in decidua in normal and ectopic pregnancy. No hybridization signal was detected in the chorionic villi. 2. In situ hybridization: Hybridization signals were detected in the cytoplasm of the decidual cells not only in normal pregnancy but also in ectopic pregnancy. No hybridization signal was detected in the trophoblast cells or endometrial glands. CONCLUSION: The human PRL-R gene is expressed in the decidual cells in early pregnancy not only in normal pregnancy but also in ectopic pregnancy. And it has been reported that the decidual cells produce PRL. These results suggest that PRL may act directly on the decidual cells by paracrine and/or autocrine mechanisms.

Blotting, Northern↗
PubMed1995

Localization of prolactin and its receptor messenger RNA in the human decidua.

Prolactin (PRL) is known as an anterior pituitary hormone. On the other hand, PRL is also produced in the human decidualized endometrium. The physiological role and site of action of endometrial PRL have not yet been clarified. This study was designed to investigate the localization of PRL receptor (PRL-R) gene-expressing cells in the human decidualized endometrium using in situ hybridization histochemistry. Sense and antisense 35S-labeled RNA probes for human PRL-R mRNA were hybridized with cryostat sections of human decidua, which were obtained from patients undergoing therapeutic abortion at 8-10 weeks of gestation. Hybridization signals for PRL-R mRNA were seen over the decidual cells. No labeled cells were seen in the chorion, amnion, or trophoblast. Comparing the localization of PRL-R gene-expressing cells to that of PRL gene-expressing cells using adjacent sections, their distributions were quite similar. These results indicate that not only PRL but also PRL-R transcripts are located in the decidual cells.

Decidua↗
PubMed1995

Localization of D-amino acid oxidase mRNA in the mouse kidney and the effect of testosterone treatment.

D-Amino acid oxidase (DAO), which catalyzes oxidative deamination of D-amino acids, is known to be highly expressed in the kidney. This study was designed to examine the localization of DAO mRNA in the mouse kidney using in situ hybridization histochemistry (ISH). For comparison, ISH for mRNA of ornithine decarboxylase (ODC), which is also highly expressed in the mouse kidney, was simultaneously performed. Adult, male mice which received 1 mg of testosterone propionate or vehicle injection, were sacrificed 14 h after injection and their kidneys were removed and processed for ISH. Hybridization signals for both mRNAs were exclusively located over the epithelial cells of the proximal tubule in the vehicle-treated animals. Signals for the DAO mRNA were observed at nearly the same hybridization intensity throughout the proximal tubule, whereas hybridization signals for the ODC mRNA were observed exclusively in the pars convoluta. Following testosterone treatment, ODC mRNA in the pars convoluta was expressed with a stronger intensity than that in the vehicle-injected animals. ODC mRNA was also expressed in the pars recta with a weaker intensity than in the pars convoluta. On the other hand, DAO mRNA expression was little affected by testosterone treatment. These results indicate that, although both genes are possibly expressed in the same cells, the expression of these genes is regulated by different mechanisms.

Amino Acids↗
PubMed1995

Efficacy of a skeletal muscle-powered dynamic patch: Part 1. Left ventricular assistance.

In this study, we examined the capability of a skeletal muscle-powered, dynamic patch to provide left ventricular assistance. An actuator was developed that used linear traction power furnished by the latissimus dorsi muscle and liquid as the medium for power transfer. The proximal portion of the muscle was dissected and was reattached to the actuator. The left ventricular apex was excised, and the dynamic patch lined with autologous pericardium was implanted during cardiopulmonary bypass. Hemodynamic studies were performed in 8 dogs after weaning from cardiopulmonary bypass. Muscle stimulation was found to significantly increase the systolic aortic pressure (91.6 versus 112.1 mm Hg; p < 0.01), the mean aortic pressure (65.2 versus 73.0 mm Hg; p < 0.01), and aortic blood flow (0.77 versus 0.92 L/min; p < 0.01). The left atrial pressure decreased from 17.9 to 16.6 mm Hg (p < 0.01). This "hybrid" left ventricular assist device possesses notable clinical advantages because of its remarkable efficacy in assisting circulation. Further experimental studies using preconditioned skeletal muscle are necessary to assess the long-term effects of this technique.

Animals↗
PubMed1995

Efficacy of a skeletal muscle-powered dynamic patch: Part 2. Right ventricular assistance.

The purpose of this study was to assess the feasibility of using a skeletal muscle-powered dynamic patch to assist the failing right ventricle. Seven adult mongrel dogs were used in the study. The proximal portion of the left latissimus dorsi muscle was harvested and reattached to the actuator to serve as a skeletal muscle energy convertor. The right ventricular free wall was fully excised and the dynamic patch was implanted under cardiopulmonary bypass. After weaning from cardiopulmonary bypass, the latissimus dorsi muscle was stimulated using a burst frequency of 33 Hz, a burst duration of 200 ms, and 1:2 synchronous mode stimulation with the native R wave. Latissimus dorsi muscle stimulation increased systolic aortic pressure (78 versus 91 mm Hg; p < 0.01), mean aortic pressure (56 versus 62 mm Hg; p < 0.05), aortic blood flow (0.73 versus 0.97 mL; p < 0.01), and systolic right ventricular pressure (41 versus 56 mm Hg; p < 0.01). The mean right atrial pressure decreased from 14 to 9.6 mm Hg (p < 0.01). Our results demonstrate that the use of a right ventricular dynamic patch powered by a skeletal muscle linear-type actuator can not only function as a right ventricular free wall substitute but also lead to the augmentation of right ventricular and global cardiac function.

Animals↗