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Biomedical subjects

K Sakamoto

Publications and source records attributed to K Sakamoto.

At least 883 records · Page 49Linked to original sources
PubMed1987

[Experimental study on pedicle fat grafts after laminectomy: comparison of pedicle fat and free fat grafts].

Scar formation adherent to the dura and nerve roots causes recurrent symptoms following laminectomy. Free and pedicle fat grafts have been performed in low-back surgery as a preventive measure. An experimental study in rats was designed to compare pedicle fat grafts and free fat grafts after wide laminectomy, for efficacy in preventing scar formation and for effects on the spinal cord. The following results were obtained. 1) Dense scar formation over the dura and degeneration of the cord were seen at control laminectomy sites. 2) Free fat grafts, examined at 2 and 4 weeks postoperatively, showed death of portions of the graft, whereas pedicle fat grafts always demonstrated the presence of living fat. 3) At 4 months postoperatively, pedicle fat grafts were statistically superior to free fat grafts, which showed scarring over the dura and degeneration of the cord. In conclusion, pedicle fat grafts were more effective in preventing dural scar formation and protecting the cord than free fat grafts.

Adipose Tissue↗
PubMed1986

Pharmacological profiles of a potential LTB4-antagonist, SM-9064.

Antagonistic activity against leukotriene B4 (LTB4) and other pharmacological activities of SM-9064 were studied in vitro and in vivo. It inhibited the chemotaxis of rat polymorphonuclear leukocytes (PMNLs) induced by LTB4 (IC50 = 1.3 X 10(-7) M, not by other chemoattractants. Its agonistic activity was much less than that of LTB4. It suppressed the Arthus reaction-induced inflammation in mice with the dose of 5 mg/kg, i.p. or 10 mg/kg, p.o. These results suggest that SM-9064 is a candidate of LTB4 antagonists, which is effective in some type of inflammation.

Animals↗
PubMed1986

Malignant fibrous histiocytoma induced by intra-articular injection of 9,10-dimethyl-1,2-benzanthracene in the rat. Pathological and enzyme histochemical studies.

Malignant fibrous histiocytoma (MFH) was produced by injection of 9,10-dimethyl-1,2-benzanthracene (DMBA) into the rat knee joint. The tumor was observed in or around the knee in nearly all the animals 13 to 36 weeks after the initial DMBA administration. Histologically, these lesions were of the storiform-pleomorphic type (39/58, 67.2%), myxoid type (9/58, 15.5%), or giant cell type (8/58, 13.8%). Six cell types reported in human MFH were confirmed and phagocytosis of 0.81-micron latex particles by histiocyte-like cells was noted by electron microscopic examination. Acid phosphatase, beta-glucuronidase, and alpha-naphthyl acetate esterase were positive in enzyme histochemical examinations. Acid phosphatase activity was electron microscopically noted primarily in the lysosomes and the Golgi apparatus of the histiocyte-like cells. Cells from the storiform-pleomorphic (M1) and myxoid (M2) type tumors were serially transplanted subcutaneously in the back of the rats, and are now at the thirtieth and fortieth passage, respectively. They also were studied by enzyme histochemical and electron microscopic techniques. Our observations suggested an undifferentiated mesenchymal cell origin of MFH. Transplantable MFH can be produced in rats by intra-articular injection of DMBA, and lesions thus produced are a useful experimental model for the investigation of the histogenesis and the effect of chemotherapy of MFH.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1986

Loss of nuclear ribonucleoprotein antigens in human skin cancers. A preliminary report.

Affinity-purified autoantibodies against nuclear ribonucleoprotein (nRNP) antigens were applied to fresh-frozen sections of benign tumors, carcinomas in situ, and carcinomas of the human skin. Using indirect immunofluorescence, the benign lesions showed speckled nuclear staining as seen in the normal epidermis. Invasive tumors such as basal cell epitheliomas and squamous cell carcinomas, in contrast, lacked immunoreactivity for nRNP antigens. Recently, ribonucleoprotein complexes defined by nRNP antigens have been postulated to be involved in the excision of intervening sequences of premessenger ribonucleic acids (RNAs). Our findings provide useful information for the understanding of the pathophysiology of human skin cancers.

Antigen-Antibody Reactions↗
PubMed1986

Explant organ culture of hamster alimentary tract epithelium.

Adult Syrian Golden hamster alimentary tract maintained as explants in organ culture was studied using the model system for hamster pancreas described by Resau et al. (1983a). Explants of esophagus, stomach, duodenum and colon were maintained in organ culture on Gelfoam sponge rafts in a high-oxygen atmosphere with serum-supplemented CMRL-1066 medium. All of the tissues were observed to show evidence of sublethal acute cell injury during the first several days of culture. Subsequently, the epithelial tissues recovered from this injury, repopulated the denuded areas of the explants and replicated within the sponge matrix. Explants were maintained in a differentiated state for 30+ days and sampled for morphology to examine to process of cell injury, repair, differentiation and replication which occurs in mucosal epithelia. The percentage of basement membrane covered by epithelia in the explants from various tissues was compared to the level of LDH in the media to reveal the relationship between viability determined by biochemical and by morphological methods. Restitution of the mucosal surface occurred in all of the explants. We conclude that adequate populations of replicating cells are maintained within the epithelium of the hamster alimentary tract tissues in vitro so that restitution can occur through migration and subsequent differentiation of the epithelial cells within the mucosa of the explants.

Animals↗
PubMed1986

Intracranial tumors in the first year of life.

Among 100 childhood brain tumors treated at Kobe Children's Hospital from May 1970 to June 1985, 18 of the children presented with symptoms during the first year of life. This paper analyzes these 18 cases. Supratentorial tumors (78%) were more common than infratentorial ones, and 67% of all the tumors were located in the central neural axis. Initial symptoms were cranial enlargement (56%), vomiting (17%), cranial deformity (11%), blepharoptosis, respiratory distress, and ataxia. Histological diagnosis of the tumors was as follows: teratoma (3 cases), medulloblastoma (3), glioblastoma (2), astrocytoma (2), ependymoma (2), craniopharyngioma (1), choroid plexus papilloma (1), hamartoma (1), lipoma (1), melanotic progonoma (1), and an undetermined type, probably medulloblastoma (1). Seventeen of the patients underwent craniotomy for tumor resection (4 total, 4 subtotal and 7 partial removal, and 2 biopsies). Additional therapeutic methods used separately and in various combinations included ventriculoperitoneal shunt, subduralperitoneal shunt, ventricular drainage, radiotherapy and chemotherapy. Nine patients died (average 98 days) after surgery. Of the 9 survivors, 6 are still alive after more than 5 years. Five of the 6 are mentally retarded and 4 are physically handicapped to some degree.

Brain Neoplasms↗
PubMed1986

Tamoxifen binding sites in human mammary cancers.

Tamoxifen binding sites (TBS) were measured using 3H-tamoxifen, the objective being to evaluate the relationships among TBS and hormone receptors and/or clinical and pathological characteristics in malignant tissues from 60 patients with mammary cancer. TBS were detected in most (96.7 per cent) cancers in the breast tissues, and the mean content and affinity were 569 fmol/mg X protein with Kd: 1.98 nM. There was no significant correlation between TBS and the estrogen receptor and/or progesterone receptor, with respect to positivity or content. However, there was a significant correlation between TBS and histological grading, thereby indicating the differentiation and the proliferative activity in this tissue. The content of TBS was significantly higher in the group with a high grade of malignancy. The TBS content significantly increased in parallel with the degree of malignancy, as related to tubule formation, nuclear pleomorphism and mitotic activity. On the other hand, there was no significant correlation between TBS and age, tumor size, lymph node status or clinical stage. These results suggest the possibility that TBS may be associated with differentiation and cell-proliferation in breast cancer tissues.

Adenocarcinoma↗
PubMed1986

Serum fatty acid concentrations in patients on postoperative parenteral nutrition with and without fat.

To examine changes in fatty acid composition of serum lipids, sixteen patients with gastric cancer were maintained on total parenteral nutrition (TPN) or intravenous feeding immediately after total gastrectomy. Subjects receiving no fat showed decreases in linoleic acid, linolenic acid and arachidonic acid and increases in palmitoleic acid and oleic acid, whereas those receiving fat emulsion showed no detectable changes. Decrease in the linoleic acid content was greater in subjects on a higher carbohydrate intake, but less in those on a higher fat intake. Multiple regression analysis of the relationships among carbohydrate intake (X1) and fat intake (X2) and changes in the linoleic acid percentage of total serum fatty acids (Y) in each case yielded an equation: Y =-4.75 X1 + 69.0 X2 - 27.9 (R = 0.885, p less than 0.05). Approximately 1 g/kg/day of fat provided in 40-50 kcal/kg/day of nonprotein energy intake was estimated to prevent decrease in the linoleic acid content in the serum fatty acid pattern during the postoperative catabolic stage.

Adult↗
PubMed1986

A case of hereditary motor and sensory neuropathy type III with a decrease in unmyelinated fibers.

We report a 3-year-old girl with hereditary motor and sensory neuropathy type III with a decrease in unmyelinated fibers. There have been few reports of such cases. The present findings suggest the possibility that the primary lesion in this disease is in the axons. We consider that more attention should be paid to the changes in unmyelinated fibers and axons in further studies on this disease.

Child, Preschool↗
PubMed1986

Evaluation of serum CA125 values in healthy individuals and pregnant women.

CA125 is an antigenic determinant associated with human epithelial ovarian carcinoma. This study was undertaken to evaluate the distribution of serum CA125 levels and the effect of smoking on these levels among healthy individuals and clarify the relation of maternal serum CA125 level and pregnancy. Among 552 healthy individuals, the distribution of serum CA125 values was demonstrated to resemble logarithmic normal distribution. Analysis of variance about age and sex revealed apparent elevation of values for women under 49 years of age in comparison with those for women over 50 years of age and men. Values for these two groups were 143 units/ml for the former and 32 units/ml for the latter, with a 99.7% confidence limit. These values exclude 99.3% of the former and 99.7% of the latter. Serum CA125 values were not affected by smoking. The measurement of serum CA125 levels in 71 pregnant women disclosed a significant elevation during the first trimester in comparison with nonpregnant women under 49 years of age. These results indicate that CA125 values must be deliberatively evaluated in young women, especially during first trimester of pregnancy.

Adult↗
PubMed1986

Clinical significance of serum CA125 values in patients with cancers of the digestive system.

A study of 347 patients with gastrointestinal diseases revealed elevation of CA125 in sera of 63% of patients with pancreatic carcinoma, 46% of patients with carcinoma of the biliary tract, 40% of patients with liver carcinoma and 11-37% of patients with other carcinomas. All of the patients with acute pancreatitis, chronic pancreatitis, cholelithiasis, and peptic ulcer had normal CA125 values, but 35% of patients with liver cirrhosis and 10% of patients with chronic active hepatitis had elevated values. Patients with disseminated carcinomas had significantly higher levels than patients with localized carcinomas. CA125 did not significantly correlate with CA19-9 or carcinoembryonic antigen in patients with pancreatic carcinoma. Ninety-seven percent of patients with pancreatic carcinoma were defined as being positive when both serum CA125 and CA19-9 were evaluated. These results indicate that CA125 is useful for differentiating pancreatic carcinoma from chronic pancreatitis, especially when supplemented with CA19-9.

Antigens, Neoplasm↗
PubMed1986

Expression of pemphigoid antigen by SV40-transformed human keratinocytes.

The expression and properties of pemphigoid antigen of SV40-transformed human keratinocytes were studied. By indirect immunofluorescence, SV40-transformed keratinocytes in passage 80-85 expressed the pemphigoid antigen as coarsely granular perinuclear fluorescence. To characterize this antigen, NP40 extracts of cells labeled with [14C]amino acids were immunoprecipitated using sera of 8 patients: bullous pemphigoid (6 patients), chronic localized pemphigoid (1 patient), and drug-induced lichen planus pemphigoides (1 patient). These immunoprecipitates were subjected to sodium dodecyl sulfate polyacrylamide gel electrophoresis and then fluorographed. All 8 sera precipitated a protein of Mr 240K, while normal human sera did not precipitate this protein. These results indicate that SV40-transformed human keratinocytes synthesize pemphigoid antigen, and that autoantibodies in the sera of pemphigoid patients with different clinical features identify the same antigen of Mr 240K in these cells.

Antigen-Antibody Reactions↗
PubMed1986

Exacerbation of pemphigus by rifampicin.

Rifampicin therapy caused exacerbation of skin lesions, rising serum pemphigus antibody titres, and decreased serum betamethasone levels in a 59-year-old man with pemphigus vulgaris. Exacerbation of pemphigus was confined to the period of rifampicin therapy and seems to be best explained by the effect of rifampicin on the metabolism of betamethasone. Physicians prescribing rifampicin for the treatment of tuberculosis should be aware of its potential to produce such an important adverse reaction.

Betamethasone↗
PubMed1986

Chronic incomplete obstruction of the ureter: a new experimental model.

To produce a chronic moderate hydronephrosis in dog, a method of partial ureteral occlusion using a specially designed polypropylene obturator was developed. In 11 of 14 dogs undergoing this procedure, excretory urography constantly revealed a moderate degree of hydronephrosis persisting for 7 weeks. Combination of this method in one ureter with the vaginal-cuff cutaneous ureterostomy, previously reported, in the contralateral ureter is a useful model for split renal function study of unilateral chronic hydronephrosis or obstructive nephropathy analogous to that of clinical case.

Animals↗
PubMed1986

[Effect of atenolol on MAO activities in SHR].

The effects of atenolol on monoamine oxidase (MAO) activities in the heart, liver, kidney and mesenteric artery in spontaneously hypertensive rats (SHR) were studied. Male SHR (5-weeks-old) were given 20 and 100 mg/kg/day of atenolol by gavage for 10 weeks. The MAO activities were determined once every 2 weeks. Atenolol produced a hypotensive effect and bradycardia in SHR. The heart weight/body weight ratio in SHR was suppressed from 4 weeks of atenolol treatment. Though atenolol induced MAO activities in the 2 weeks treated heart and 4-6 weeks treated liver, it inhibited the increase of MAO activities in all prepared organs after 10 weeks treatment. The MAO activities of the heart were more markedly inhibited than in the other organs by the treatment of atenolol. Atenolol did not lower the Km value, but reduced significantly the Vmax value of the 10 weeks treated heart MAO. Atenolol had no effect on the MAO activities in vitro. These results suggest that the changes of the MAO activities in the organs of SHR by the treatment of atenolol may be relative to the hypotensive and bradycardic effects of the cardioselective beta-adrenoceptor blocking agent.

Animals↗