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Biomedical subjects

I Satoh

Publications and source records attributed to I Satoh.

At least 37 records · Page 2Linked to original sources

Two-dimensional arrangement of a functional protein by cysteine-gold interaction: enzyme activity and characterization of a protein monolayer on a gold substrate.

We have characterized the functional protein, myosin subfragment 1 (S1), attached to a gold substrate by the sulfhydryl groups of cysteine in proteins. The amino groups of the regulatory light chain (RLC) isolated from myosin were labeled with a radioisotope (125I), and the labeled RLC was incorporated into S1 from which the RLC had been removed. The radiation from 125I showed that S1 molecules had attached to the gold and, through the interference effect of the monochromatic radiation from 125I, provided information about the position of labeled RLC sites in the S1 monolayer. The interference fringes showed that the RLC was located close to the gold surface and that all of the adsorbed S1 molecules had the same orientation. We confirmed that the motor function of S1 on the gold surface is maintained by observing sliding movement at low ionic strength and by observing the detachment at high ionic strength of fluorescent actin filaments in the presence of ATP. We also found that the adsorbed S1 molecules were not removed from the Au surface by a reducing agent. Thus the Au-S bond is more stable than the S-S bond.

Actins↗

Role of pulmonary afferent inputs in vocal on-switch in the cat.

The purpose of this paper is to elucidate the possible role of pulmonary afferent inputs in triggering inspiratory-vocal (I-V) and Vocal-inspiratory (V-I) transitions during periaqueductal gray (PAG)-induced vocalization. Under ketamine anesthesia, we investigated the effects of changes in pulmonary afferent inputs on the PAG-induced vocal motor pattern by transection and electrical stimulation of the cervical vagus nerve in non-paralyzed cats and by lung inflation and deflation in paralyzed cats. After bilateral vagotomy, PAG stimulation induced apneusis; strong suppression of the I-V transition disrupted the vocal rhythmicity. Electrical stimulation of the central end of the cut vagus nerve during PAG stimulation immediately caused an I-V transition. In paralyzed cats during the withholding of lung inflation, the I-V transition was also suppressed during PAG stimulation. Lung inflation during PAG stimulation caused a phase switch from inspiration to fictive vocalization, i.e. I-V transition. In contrast, this fictive vocal phase maintained by lung inflation was terminated by lung deflation, i.e. V-I transition. These findings suggest that pulmonary vagal afferent feedback plays an important role in triggering and terminating vocalization.

Afferent Pathways↗

Reducing nurses'. Workload using a computerized nursing support system linked to the hospital information system.

A computerised nursing support system (CNSS) linked to the hospital information system (HIS) was developed and has been in use for one year, in order to reduce the workload of nurses. CNSS consists of (1) a hand held computer for each nurse (2) desk-top computers in the nurses' station and doctors' rooms (3) a data server (4) an interface with the main hospital information system. Nurses enter vital signs, food intake and other information about the patients into the hand held computer at the bed-side. The information is then sent automatically to the CNSS data server, which also receives patients' details (prescribed medicines etc.) from the HIS. Nurses and doctors can see all the information on the desk-top and hand held computers. This system was introduced in May 1995 into a university hospital ward with 40 beds. A questionnaire was completed by 23 nurses before and after the introduction of CNSS. The mean time required to post vital data was significantly reduced from 121 seconds to 54 seconds (p < 0.01). After three months 30% of nurses felt CNSS had reduced their workload, while 30% felt it had complicated their work; after five months 70% noted a reduction and 0% reported that CNSS had made their work more complex. The study therefore concludes that the interface between a computerised nursing support system and the hospital information system reduced the workload of nurses.

Humans↗

[Phase II study of paclitaxel (BMS-181339) in patients with ovarian cancer by 3-hour intravenous infusion].

A phase II study of Paclitaxel in patients with ovarian cancer by 3-hour intravenous infusion was undertaken by a cooperative study group of 30 institutes. Of 66 cases enrolled, 57 cases were evaluable for efficacy, and 63 cases were evaluable for safety. In spite of the fact that all cases for efficacy evaluation were previously treated with chemotherapy including platinum-based drugs, 2 cases of complete response (CR) and 15 cases of partial response (PR) were observed, with a response rate of 29.8% (The 95% confidence interval of response rate was 18.4-43.4%). Paclitaxel also showed 28.2% (11/39) response rate in patients refractory to treatment by platinum-based drugs. Histologically, the response rates were 28.9% (11/38) in serous adenocarcinoma, 40.0% (2/5) in clear cell adenocarcinoma and 25.0% (1/4) in mucinous adenocarcinoma. As the major laboratory abnormalities, leukopenia, neutropenia and decrease in hemoglobin were observed with incidence rates of 98.4% (62/63), 95.2% (59/62) and 85.7% (54/63), respectively. However, these abnormalities were clinically manageable by either withdrawal of medication, administration of antibiotics, G-CSF or metachysis etc. In addition, thrombocytopenia, elevation in GOT and GPT were seen with moderate incidence. Peripheral neuropathy was a major adverse symptom with an incidence of 79.4% (50/63), followed by alopecia, myalgia, arthralgia and fever. However, the majority of these adverse reactions were less than grade 3. From these findings, we confirmed that 3-hour intravenous infusion of Paclitaxel was a clinically useful chemotherapeutic agent in patients with ovarian cancer.

Adult↗

Conservative management of idiopathic pneumoperitoneum masquerading as peritonitis: report of a case.

Pneumoperitoneum is most commonly caused by the perforation of a hollow viscus, in which case an emergency laparotomy is indicated. We report herein the case of a patient who presented with the signs and symptoms of peritonitis, but who was found to have idiopathic pneumoperitoneum which was successfully managed by conservative treatment. A 70-year-old man presented with epigastric pain, nausea, and a severely distended and tympanitic abdomen. Abdominal examination revealed diffuse tenderness with guarding, but no rebound tenderness. He was febrile with leukocytosis and high C-reactive protein. Chest X-ray and abdominal computed tomography demonstrated a massive pneumoperitoneum without pneumothorax, pneumomediastinum, pneumoretroperitoneum, or subcutaneous emphysema, and subsequent examinations failed to demonstrate perforation of a hollow viscus. Thus, a diagnosis of idiopathic pneumoperitoneum was made, and the patient was managed conservatively, which resulted in a successful outcome. This experience and a review of the literature suggest that idiopathic pneumoperitoneum is amenable to conservative management, even when the signs and symptoms of peritonitis are present.

Aged↗

[Tetralogy of Fallot with a restrictive ventricular septal defect caused by a membranous flap].

A 5-year-old boy who had typical tetralogy of Fallot (TOF) with mild cyanosis was referred to us. Preoperative echocardiogram revealed that in addition to the TOF morphology, an abnormal piece of tissue attached to the right side of the ventricular septum was floating and obstructing flow through the ventricular septal defect (VSD) in systole. Preoperative cardiac catheterization showed suprasystemic right ventricular pressure with a gradient of 60 mmHg between the right ventricle and the aorta, and a right ventriculogram demonstrated a narrow radiolucent structure beneath the aortic valve in the right ventricle. During surgery a fibrous membranous tissue, with no relation to the tricuspid valve, was found to extend from the edge of the VSD to the aortic valve and to partially occlude the defect. This tissue was used as a suture anchorage for patch closure of the defect. Preoperative echocardiography is useful to detect such flaps and early surgical correction should be done to prevent right ventricular failure resulting from right ventricular pressure overload.

Child, Preschool↗

Immunohistochemical localization of gonadotropin-associated peptide (GAP) in the human hypothalamus.

GAP was immunohistochemically localized for the first time in the human hypothalamus. GAP-immunoreactivity was present in the cytoplasm of neuronal cells in the arcuate nucleus. GAP-immunoreactive nerve fibers were also present in the primary plexus around capillaries in the infundibular region. No GAP-immunoreactive neurons were detected in the paraventricular nuclei or supraoptic nuclei.

Arcuate Nucleus of Hypothalamus↗

[Informed consent of the family in the chemotherapy for lung cancer].

In Japan where the question of cancer notification has yet to be resolved, it is difficult to obtain an informed consent from the patient himself in clinical studies of the chemotherapies for cancer. In fact, the chemotherapy is administered while not enough explanation is given to the family let alone the patient. Such is the present situation. For the purpose of finding out the best possible method at present, we carried out a method whereby an informed consent of the family is substituted for a consent of the patient in phase II study of inoperable non-small cell carcinoma of the lung. As a result, the consent was obtained from 21 (91.3%) out of 23 families. This method should be taken into consideration as a feasible one under the present circumstances. It was in only one family (4.3%) that a consent on the notification of diagnosis from the family to the patient was obtained. In order for the informed consent to be established, efforts to form a social consensus on cancer notification are needed.

Adult↗

Growth dynamics of the heart from perinatal period to childhood.

In order to obtain information useful for the diagnosis of fetus and newborn heart disease, we established a theoretical model of perinatal cardiac growth. We measured with the use of ultrasonic cross-section imaging system the mitral valve ring dimension, tricuspid valve ring dimension, and total cardiac dimension as morphological parameters of the heart in 45 cases composed of fetuses and children. The obtained data were entered into a computer. With the use of these data, simulation was made on the basis of the general theory of biological development. The present simulation showed that from the fetal stage to childhood the growth rates of the foregoing three morphological parameters mutually differ, but during the period of growth to the age of 12 years of the present study, they all demonstrated continuous growth up to 3 1/2 years after birth when they reached a growth saturation level.

Aging↗

[Root resorption of vital and endodontically treated teeth in orthodontic movement].

Orthodontic tooth movement frequently induces the resorption of the tooth root, although valuable information concerning the relationship between the root resorption and force magnitude, duration and types of tooth movement and the condition of periodontium obtained. However, it is incompletely known that the situation of candidated tooth itself of orthodontic movement in which pulpectomized non-vital condition influence the process of root resorption and subsequent repairing. Thus, the study was conducted to clarify the effect by the pulpectomy accompanied with tooth movement on the process of root resorption and regeneration of periodontium. A hundred and fifty Wistar rats, weight 180-200 g, 6 weeks old, were used as experimental animals. Prior to experimental tooth movement, first molars of 50 rats were received pulpectomy on both sides followed by filling of root canal (first group) and those of another 50 rats on single side (second group). Maxillary first molars of the other 50 rats were saved as a vital dental pulp control (third group). The first and the third groups of animals were then subjected to experimental tooth movement with the interproximal insertion of elastic rubber as described by Waldo (1953) for 3 days, 1, 2, 3 and 4 weeks. After tooth movement was terminated, animals were sacrificed by ether inhalation or by perfusion of glutaraldehyde fixation solution. The upper jaw from each rat was dissected and prepared specimens for non-decalcified section and light microscopic section. Root resorption and regeneration of cementum were evaluated quantitatively using the modular system for semiautomatic quantitative evaluation of images on the light microscopic section. Occurrence of external root resorption with multinucleated odontoclast associated with experimental tooth movement in pulpectomized tooth were lesser and later than those of vital teeth. These findings suggest that the dental pulp plays an important role in the processes of root resorption and remodeling of cementum associated with orthodontic tooth movement.

Animals↗

Decrease of transplantability by the immunopotentiators, OK-432 and interleukin-2: experiments on a human hepatoma cell line in nude mice.

The relationship between nonspecific cytotoxic activity of spleen cells and the resistance against the graft challenge of a human hepatoma cell line (HCC-M) was investigated in nude mice. Two administrations of an immunopotentiator, OK-432 or human interleukin-2, prior to the subcutaneous inoculation of HCC-M cells, which was performed 24 h after the last administration, significantly inhibited the tumor development in terms of rate of tumor take and tumor size. This effect was abrogated by simultaneous administration of an anti-asialo GM1 (ASGM1) antiserum. There was a significant inverse correlation between tumor volume and spleen cell cytotoxicity which was determined at the time of HCC-M cell inoculation against a YAC-1 or HCC-M target. Spleen cell cytotoxicity enhanced by these immunopotentiators could not completely be abolished by in vitro treatment with ASGM1 and complement. This result suggests that effector cells of the enhanced cytotoxicity consist of heterogeneous cells including both ASGM1+ natural killer cells and other nonselective cytotoxic cells. These results suggest that nonspecific cytotoxic cells play crucial roles in the resistance against tumor cell challenge and that the total level of cytotoxic activity of these cells at the time of tumor cell challenge is a key factor which determines tumor development.

Animals↗

Reduced vasoactive intestinal polypeptide immunoreactivity in the pituitaries of hormone-deficient mutant mice.

The prolactin-producing cells of the bovine anterior pituitary were found to contain a vasoactive intestinal polypeptide (VIP) immunoreactive substance, thus suggesting a role for VIP in the regulation of prolactin release. The pituitaries of the dw and lit strains of mutant mice, congenitally deficient in prolactin-producing cells, and hyt mice, which were found to have reduced numbers of prolactin-producing cells, showed a markedly reduced VIP immunoreactivity. Hypothalamic VIP immunoreactivity, however, was found to be unchanged in the three strains of mutant mice, indicating that the high concentration of VIP in the hypothalamus does not derive from the adenohypophysis through retrograde flow. The deficiency in the mutant mice seems to be due to the lack of prolactin target cells in the pituitary.

Animals↗