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Biomedical subjects

K Sakamoto

Publications and source records attributed to K Sakamoto.

At least 667 records · Page 37Linked to original sources
PubMed1991

[Statistical observations of pemphigus at the Nara University Hospital from 1975 to 1989].

From 1975 to 1989, 12 patients with pemphigus vulgaris (PV) and 19 with pemphigus foliaceus (PF) were treated with systemic or topical corticosteroids at the Nara University Hospital. All 12 patients with PV were treated with oral corticosteroids (initial dose of prednisolone: 15-70 mg/day) and 4 of 12 patients showed prolonged clinical remission (up to 9 years) without corticosteroids. Of 19 patients with PF, 16 patients were treated with oral corticosteroids (initial dose of prednisolone: 8-40 mg/day) and 3 patients were treated with only topical application of corticosteroids. In PF, 7 of 16 patients treated with systemic corticosteroids and all 3 patients treated with topical corticosteroids also showed prolonged clinical remission (up to 10 years). These observations suggest that most of the patients with pemphigus respond well to the treatment of relatively small or moderate dosage of corticosteroids.

Administration, Oral↗
PubMed1991

[A case of corrosive esophagitis with stenosis].

A 41-year-old man was admitted to our hospital because of pharyngeal pain and vomiting after intentionally swallowing sodium hydroxide. Gradually esophageal stenosis took place. After 9 months from the taking poison the patient was operated. We tried blunt dissection of esophagus. But the procedure failed in because the wire of stripper was cut. So performed total esophageal resection under the right thoracotomy. The right side colon was used to re-construction through antero-sternal space that was anastmosed to cervical esophagus and stomach. The postoperative course was uneventful.

Adult↗
PubMed1991

[Absent pulmonary valve syndrome: surgical approach for the worst group included in symptomatic neonates].

Absent pulmonary valve syndrome (APVS) has been classified to two groups. One is severely symptomatic infant group and the other no or slightly symptomatic. But we think that severely symptomatic group should be divided into the worst neonate group and the other. This worst group, that contains neonates who can not be weaned from the respirator after surgical intervention including corrective surgery because of severe bronchomalacia and/or peripheral bronchial stenosis, has already severe respiratory distress and needs ventilatory support while high pulmonary vascular resistance is maintained. Three patients of this group were operated on at 2, 13 and 2 days of age and there were two late hospital death. The last patient underwent ligation of main pulmonary artery (mPA) and left modified Blalock-Taussig shunt (MBTS) with phi 4 mm polytetrafluoroethylene graft and was extubated on the next day. The management of this group should aim at controlling the pulmonary regurgitation as early as possible to decrease the progressive airway obstruction and minimize pulmonary tissue damage. Ligation of mPA and MBTS can be performed without cardiopulmonary bypass and eliminates pulmonary regurgitation and controls the pulmonary blood flow less than the total correction. In the point of protecting bronchi and lung and reducing the risk of surgical intervention in critical neonatal period, ligation of mPA and MBTS can be safer and more effective operation for the worst APVS neonate than the total correction with insertion of artificial valve.

Blood Vessel Prosthesis↗
PubMed1991

[Consequences of DNA damage and the relationship between respiratory diseases in childhood and in adult hood].

The purpose of this study was to test the hypothesis that lung injury at an early postnatal age results in respiratory disease in later life. One mg/g body weight of bromodeoxyuridine (BrdU) was injected intraperitoneally in suckling rats on day 6 after birth. The animals were sacrificed at 2 and 8 wk of age. Although the lungs of BrdU-treated animals at 2 wks of age were similar to those in the control animals, the BrdU-treated animals at 8 wks of age had an abnormal enlargement of airspace and an increased compliance. The results show that lungs injured cytogenetically in early postnatal life may develop pulmonary functional and structural abnormalities in later life.

Age Factors↗
PubMed1990

[Low-dose-rate teletherapy combined with hyperthermia as a boost therapy].

The efficacy of the low dose rate teletherapy (LDRT; 1 Gy/hr, 4 Gy/day, 2-3 times/week) combined with hyperthermia as a boost therapy (H (+) group) against far advanced carcinomas was examined. The treatment results in H (+) group (17 esophageal carcinomas, 3 pancreatic and bile duct carcinomas and 5 other carcinomas) were compared with the ones in H (-) group (38 esophageal carcinomas, 5 pancreatic and bile duct carcinomas and 13 other carcinomas) which were treated with the LDRT (1 Gy/hr, 7 Gy/day, every day) as a boost. A total dose of 14-24 Gy by the LDRT was followed after the irradiation of 50-60 Gy by conventionally fractionated method (1.5-2 Gy/day). H (+) cases were treated with 42.5 degrees C, 1 hour hyperthermia immediately before the LDRT and 19 cases (76%) were successfully heated. There were no significant differences between H (+) group and H (-) group in local control, late severe complication and survival rates, even when they were corrected by primary sites and stages. The incidence of metastases was higher in H (+) group. It was considered that the gain of the combination of the LDRT and the hyperthermia as a boost therapy was a little.

Adult↗
PubMed1990

[The effects of uneven fractionated irradiation on mouse squamous cell carcinoma and normal tissue].

In uneven fractionated radiotherapy combining large doses and small doses, we studied the influence of the order of their combination on tumors and on normal tissues, using squamous cell carcinoma and skin reaction of mice. The number of fractions was 6, and we used various combinations of 4 small doses and 2 large doses (4 times larger). The antitumor effect was smallest when a large dose was given at the end of treatment, but in skin reactions, there was no difference in effect even when the order of the combination of large and small doses was changed.

Animals↗
PubMed1990

Binding of the gamma-subunit of retinal rod-outer-segment phosphodiesterase with both transducin and the catalytic subunits of phosphodiesterase.

The gamma-subunit of retinal rod-outer-segment phosphodiesterase (PDE-gamma) is a multifunctional protein which interacts directly with both of the catalytic subunits of PDE (PDE alpha/beta) and the alpha-subunit of the retinal G (guanine-nucleotide-binding)-protein transducin alpha (T alpha). We have previously reported that the PDE gamma binds to T alpha at residue nos. 24-45 [Morrison. Rider & Takemoto (1987) FEBS Lett. 222, 266-270]. In vitro this results in inhibition of T alpha GTP/GDP exchange [Morrison, Cunnick, Oppert & Takemoto (1989) J. Biol. Chem. 264, 11671-11681]. We now report that the inhibitory region of PDE gamma for PDE alpha/beta occurs at PDE gamma residues 54-87. This binding results in inhibition of either trypsin-solubilized or membrane-bound PDE alpha/beta. PDE gamma which has been treated with carboxypeptidase Y, removing the C-terminus, does not inhibit PDE alpha/beta, but does inhibit T alpha GTP/GDP exchange. Inhibition by PDE gamma can be removed by T alpha-guanosine 5'-[gamma-thio]triphosphate (GTP[S]) addition to membranes. This results in a displacement of PDE gamma, but not in removal of this subunit from the membrane [Whalen, Bitensky & Takemoto (1990) Biochem. J. 265, 655-658]. These results suggest that low levels of T alpha-GTP[S] can result in displacement of PDE gamma from the membrane in vitro as a GTP[S]-T alpha-PDE gamma complex. Further activation by high levels of T alpha-GTP[S] occurs by displacement of PDE gamma from its inhibitory site on PDE alpha/beta, but not in removal from the membrane.

Animals↗
PubMed1990

[Improved methods for transseptal left heart catheterization].

Although the transseptal approach is useful for evaluation of reliable hemodynamics, this technique is not used commonly for its invasive procedure. We report a new technique for transseptal left heart catheterization utilizing J-shaped guide wire (0.018 inch). The guide wire is available for protecting the atrial wall from perforation by transseptal needle. Transseptal approach was performed by this technique in 58 patients with aortic valvular disease and mitral stenosis, including 6 cases of percutaneous transluminal mitral commissurotomy. We conclude that the J-shaped guide wire and the new technique make transseptal approach a safe and reliable procedure for even inexperienced hands.

Adolescent↗
PubMed1990

DNA mutagenesis and recombination.

The polymerase chain reaction is used for site-specific mutagenesis and for DNA recombination without any enzymatic reaction in vitro, apart from DNA amplification.

DNA, Circular↗
PubMed1990

Induction of tumor cytotoxic immune cells using a protein from the bitter melon (Momordica charantia).

The fruit and seeds of the bitter melon (Momordica charantia) have been reported to have anti-leukemic and antiviral activities. This anti-leukemic and antiviral action was associated with an activation of murine lymphocytes. A partially purified protein factor from the bitter melon caused an infiltration and activation of peritoneal exudate cells in C57B1/6J, C3H/HeJ, and C3H/HeN mice. When the extract was injected twice a week at 8 micrograms of protein per ip injection for 0-4 weeks, the peritoneal exudate cells from the treated mice were cytotoxic in a long-term (18-hr) 51Cr-release assay against a range of labeled targets: L1210, P388, and MOLT-4 tumor cells. Cytotoxicity was also observed against YAC-1 targets in a short-term (4-hr) assay. Fractionation of the cytotoxic immune cells implicated a nonadherent cell population which was capable of killing an NK-sensitive cell line in a 4-hr 51Cr-release assay. Unit gravity sedimentation studies indicated that the cytotoxicity was due to either a neutrophil or a large lymphocyte. Antibody depletion experiments using antibody to asialo GM1, an NK cell-specific antibody, depleted cytotoxicity observed in nonadherent, Ficoll/Hypaque-separated PEC. This suggests that at least part of the anti-leukemic activity of the bitter melon extract is due to the activation of NK cells in the host mouse.

Animals↗
PubMed1990

Prevention of fatal infections by recombinant human interleukin 1 alpha in normal and anticancer drug-treated mice.

The preventive capability of interleukin 1 alpha (IL-1) against bacterial infections was estimated in normal and anticancer drug-treated BALB/c mice in comparison with OK432, granulocyte colony-stimulating factor, interferons alpha and gamma, and interleukin 2. Pretreatment with IL-1 (days -4 and -2) resulted in a significantly higher survival rate in normal mice inoculated i.p. with Klebsiella pneumoniae, Pseudomonas aeruginosa or Listeria monocytogenes (day 0). The i.p. and s.c. administrations of IL-1 were equally effective for the induction of antibacterial resistance. Pretreatment with OK432 showed an equal degree of resistance to i.p. infection but was effective only by i.p. administration. Enhanced antibacterial resistance by IL-1 and OK432 was also observed in cyclophosphamide- and aminomethylpyrimidinylmethylchloroethylnitrosourea hydrochloride-pretreated (day -5) normal hosts and in cyclophosphamide-treated tumor-bearing hosts. In the case of granulocyte colony-stimulating factor (i.p. or s.c.) (days -4 to -1), a statistical difference in survival rate between granulocyte colony-stimulating factor and its vehicle-treated groups was observed in cyclophosphamide-pretreated hosts, but not in normal hosts or aminomethylpyrimidinylmethylchloroethylnitrosourea hydrochloride-pretreated hosts. Viable bacteria in the peritoneal cavity and blood at 12 h after i.p. infection of K. pneumoniae correlated well with the survival rate. In IL-1-pretreated hosts, the earlier and increased accumulation of neutrophils into peritoneal cavity after the infection was observed and the number of inflammatory cells in peritoneal cavity correlated well with the survival rate. The enhanced resistance to bacterial infection by IL-1 was suggested to be in part due to the enhanced cellular defense mechanisms. The prophylactic administration of IL-1 would be beneficial for the management of serious infections in cancer patients.

Animals↗
PubMed1990

[Successful treatment by using a pedicled omental flap for mediastinal infection in the presence of a external valved conduit].

Mediastinal infection is one of serve and fatal complications after cardiac surgery, especially in the presence of an artificial graft. A case of successful treatment by using a pedicled omental flap for mediastinal infection in the presence of an external valved conduit is reported. a 10-year-old girl who had implanted the 12 mm porcine valved conduit for truncus arteriosus at age 9 months, underwent replacement of the old conduit with a 18 mm valved conduit. On the 9th postoperative day, as soon as mediastinal infection was proved by positive culture of the drainage from the chest tube, a reoperation was performed to debride and irrigate the mediastinum. Irrigation with povidone-iodine and antibiotics was continued for 3 weeks until improvement of CRP levels and negative drainage cultures. Then the heart and the valved conduit were wrapped with the pedicled omental flap and the skin was closed. She was without any evidence of infection for 3 months after operation. Use of a pedicled omental flap might be an effective method for treatment of mediastinal infection in the presence of an external conduit.

Blood Vessel Prosthesis↗
PubMed1990

[Delayed midsternal wound reconstruction for infants without secondary sternal closure].

Three infants, aged 11 days, 19 days and 48 days, underwent two Jatene operations and one modified Norwood operation. The sternum was left open and the skin defect was covered with a silicon sheet in all three patients. Delayed sternal closure was impossible because of hemodynamic deterioration in all three patients. Consequently delayed midsternal wound reconstruction was applied. One rectus abdominis muscle flap was turned up and the defect between the split sternum was filled with this muscle flap. Bilateral axillary incision was made to decrease the skin tension and the midsternal wound was closed with cutaneous advancement flaps. Bilateral axillary defects were covered with mesh skin implantation. All three patients recovered after this procedure. We propose this technique for the cases in which the delayed sternal closure is impossible.

Abdominal Muscles↗
PubMed1990

In vivo measurement of intra- and extracellular space of brain tissue by electrical impedance method.

An impedance method was applied to evaluate transcellular fluid shifts in ischaemic brain oedema. The admittances (apparent electrical conductivities) of tissues were measured at varied frequencies based on a simple model of an electrical equivalent circuit for tissues, which consisted of Re (resistivity of extracellular fluid), Ri (resistivity of intracellular fluid) and Cm (capacitance of cell membrane). Calculated were Re, Ri, Rinf (resistivity of total fluid), Re/Ri and alpha (Cole-Cole distribution index) of brain tissue by Cole-Cole an arc of a circle. During ischaemia induced by cat middle cerebral artery occlusion (MCAO), the parameters were examined continuously. After MCAO, cerebral blood flow (CBF) decreased to under 10 ml/100 g/min. Then Re and Re/Ri increased, but Ri decreased. These results indicated that fluid shift from extracellular (EC) to intracellular (IC) space occurred after ischaemic insult. Rinf showed no changes during ischaemia of 30 min, which demonstrated no changes of total fluid volume. Using this impedance technique, fluid accumulation and shift may be examined by changes of Re, Ri, Re/Ri and Rinf in various types of brain oedema in vivo.

Animals↗
PubMed1990

Recurrent low-grade glioma in children with special reference to computed tomography findings and pathological changes.

Recurrent low-grade gliomas in children were studied with special reference to correlation between the computed tomography (CT) scan and pathological findings at recurrence. During the past 16 years (1970-1986) 105 cases of primary pediatric brain tumors were treated in our hospital. Seventeen of these had low-grade glioma, seven of which (five astrocytomas, one ependymoma, and one subependymoma) had recurrence of tumor by the end of 1987. The enhanced CT findings were classified into three types--cystic, false cystic, and solid, according to Lapras' classification. The pathological findings of recurrent tumors were reviewed with particular attention to malignant transformation. The results showed that in two out of three cases where CT findings had changed from initial cystic to solid type at recurrence malignant transformation was revealed. Enhanced CT scan was also useful for detecting small asymptomatic recurrent tumors in children. On the other hand, surgical procedures and adjuvant therapies demonstrated no significant relationship with recurrence. It is suggested that the recurrence of low-grade glioma in children is not rare, and that changes in findings on contrast enhanced CT might reflect malignant transformation in a recurrent tumor, necessitating a careful follow-up.

Adolescent↗
PubMed1990

Comparative studies on the expression of gastrointestinal-cancer-associated antigen, PA8-15, CA19-9 and the blood-group antigens in non-malignant and malignant human pancreatic tissues.

The expression of PA8-15 antigen and the blood-group-related antigens A, B, O, Le(a), Le(b), Le(x), and Le(y), as well as CA19-9, were examined in the normal pancreas and in specimens from benign and malignant pancreatic tissue by the avidin-biotin-immunoperoxidase technique. A correlation was found between the expression of PA8-15, Le(a), and CA19-9 in some cases. However, in the cancer tissues in which neither Le(a) nor CA19-9 could be demonstrated, strong expression of PA8-15 was observed. The reactivity of monoclonal antibody (mAb) PA8-15 with pancreatic cancer tissue was not inhibited by the preincubation of the sections with the mAb anti-Le(a) (CO514) and mAb CA19-9 (CO19-9) indicating that the epitope recognized by PA8-15 is different from that detected by the other two antibodies. Moreover, unlike Le(a) and CA19-9, PA8-15 was also expressed in cancer cells of patients of the Le(a-b-) type. The results suggest that mAb PA8-15 recognizes a sialylated molecule related to Le(a) but different from CA19-9, and seems to be an additional useful marker for pancreatic cancer.

Adenocarcinoma↗
PubMed1990

A pilot study on the usefulness of a new test for mass screening of colorectal cancer in Japan.

A new screening test (Shamsuddin and Elsayed, 1988) based on the enzymatic detection of the disaccharide beta-D-Gal(1----3)-D-GalNAc in the rectal mucus of patients with colorectal (CR) cancer and precancerous conditions such as inflammatory bowel disease (IBD) and polyp (precancerous lesions) was evaluated in 85 Japanese patients. Following a 15-minute reaction, a sensitivity of 80.0% (8/10) for CR cancer and 72.2% (8/11) for precancerous lesions was obtained. The overall specificity for combined CR cancers and precancerous lesions was 62.2% (28/45). Correlation with abnormal mucin production in the tissues of CR cancer and precancerous lesions was studied by high-iron diamine-Alcian blue and/or periodic acid-Schiff-Alcian blue (pH = 1.0). The agreement of the results with this test was 77.8% (7/9) for CR cancers and 75.0% (6/8) for precancerous conditions. Because of the simplicity of this test, low cost, stability of the sample and reagents and accuracy for CR cancer and precancerous lesions, the test may have potential use for mass screening of cancer and high risk individuals, particularly CR cancer in Japan.

Biomarkers, Tumor↗