Biomedical subjects
Publications and source records attributed to Y Sakamoto.
Explore the source record for details and available documents.
This is a case report of an adrenal myelolipoma, accidentally diagnosed during a work-up for bladder tumor. A 67-year-old male presented with the chief complaint of gross hematuria. He was subsequently diagnosed as having a bladder tumor, which was resected transurethrally and was found to be a transitional cell carcinoma of Grade 2 and Stage pT2. During further examination for metastasis computed tomography (CT) scan revealed a round tumor (approximately 5 cm in diameter) in the left adrenal. A tentative diagnosis was reached based on the scan, and surgery was undertaken to remove the tumor. A well-encapsulated tumor, yellowish and partly dark brown in color and 60 grams in weight, was retrieved. The tumor consisted of mature lipoid cells with myeloid cells scattered among them which verified the pathological diagnosis of adrenal myelolipoma. The present case is the 16th clinical case of adrenal myelolipoma reported in the Japanese literature.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Suppressor cells for delayed footpad reaction (DFR) against syngeneic testicular cells (TC) were detected in the spleen cells of donor mice immunized intravenously (iv) with viable syngeneic TC. Cyclophosphamide (CY)-pretreated recipients were given spleen cells from donors iv, immunized subcutaneously (sc) with syngeneic TC, and the footpad reaction at 24 hr was elicited with syngeneic TC 6 days after immunization. DFR in the recipients was suppressed by the transfer of spleen suppressor cells. The suppressor cells induced were Thy-1+, CY-sensitive, adult thymectomy (ATx)-resistant and act only at the induction stage. They directly suppress the generation of effector T cells for delayed-type hypersensitivity (DTH). When mice pretreated with CY were actively immunized with syngeneic TC, DFR could be provoked to a measurable level only when they were immunized sc. However, peritoneal exudate cells of those tolerant mice immunized sc without CY pretreatment or immunized iv with CY pretreatment also passively transferred DFR locally, suggesting the existence of effector T cells for DTH even in tolerant mice.
A high-performance liquid chromatographic method is described for the assay of angiotensin-converting enzyme in human serum and for the separation of angiotensins and their analogues after pre-column fluorescence derivatization with benzoin. Angiotensin II, formed enzymatically from angiotensin I, is converted into a fluorescent derivative which is then separated isocratically from the substrate and biological substances in the enzyme reaction mixture on a reversed-phase column (TSK gel ODS-120T). The lower limit of detection for angiotensin II is 0.66 pmol per enzyme assay tube. The method is simple and sensitive, and requires as little as 5 microliter of human serum. Angiotensin analogues can also be separated and quantified by the chromatographic technique, and thus this method permits the use of the analogues of angiotensin I as substrates.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Peripheral nerve myelin contains a large quantity of integral glycoproteins, such as PO and PASII protein. The present paper reports a fast and sensitive method for separation of these glycoproteins. High performance liquid chromatography (HPLC) with TSK-GEL 3000 SW column in the presence of sodium dodecyl sulfate (SDS) or lithium dodecyl sulfate (LDS) was used. Whereas the separation of PO and PASII was inadequate with low concentrations of the detergent, better separation profiles were obtained with high concentrations (1-2%) of the detergent in 0.1 M phosphate buffer. The two glycoproteins were able to be purified by rechromatography. High concentration of the detergent presumably diminished interaction between these glycoproteins. LSD-phosphate, SDS-lithium citrate or SDS-Tris buffer as an eluent was also compared with SDS-phosphate system. This method will be applicable to the detection and purification of proteins from myelin or other organelles.
The losses of blood group antigens A, B, and H in carcinoma tissue of the uterine cervix were studied by the avidin-biotin-peroxidase complex (ABC) method and the relations of these losses to invasion and dedifferentiation of primary cancer were examined. The incidence of cases showing complete loss of A or B antigen increased in proportion to the progression of cancer, but in most cases even of invasive cancer, H antigen, the precursor of A and B antigens, was detected. Complete loss of H antigen was not demonstrated in well-differentiated keratinizing invasive carcinomas, but was seen in 15% (15/101) of the cases of large cell non-keratinizing type cancer and 50% (8/16) of those of small cell non-keratinizing type cancer. No relationship was found between losses of A, B, and H antigens and parametrial spread of carcinoma or metastasis to the pelvic lymph nodes, but the incidence of death within 2 years after hysterectomy was higher in H antigen-negative cases than in H antigen-positive cases. These results indicate that loss of A and B antigens depends on some activity of invasion of cancer, while loss of H antigen strongly indicates dedifferentiation of cancer cells and also may indicate a poor prognosis.
There have been three articles in the clinical literature of ergonovine maleate-induced bronchospasm. The effect of the alkaloid on isolated canine tracheal smooth muscle was analyzed to investigate the mechanism of ergonovine-induced airway smooth muscle contraction. Both ergonovine and 5-hydroxytryptamine (5HT, serotonin) contracted the smooth muscle preparations with EC50s of 1.35 X 10(-8) mol/L and 5.06 X 10(-7) mol/L, respectively. The maximal contractile response observed with ergonovine was approximately 30% less than that observed with 5HT. Methysergide competitively blocked both ergonovine and 5HT responses with similar calculated pKB values (8.33 against ergonovine and 8.46 against 5HT) and also similar pA2 values determined by Schild plots (8.50 and 8.45, respectively). The relative affinity and efficacy of ergonovine versus 5HT were determined by use of a concentration of the irreversible antagonist, phenoxybenzamine, which partially blocked receptor sites. The calculated affinity of ergonovine was about 16 times higher than that of 5HT. The relative efficacy at EC100 for ergonovine was 0.2, but at EC10 it was 41.9 (5HT efficacy = 1). Ergonovine 10(-9) or 10(-8) mol/L shifted the 5HT dose-response curve to the right without reducing the maximal response, but the shift was nonparallel. Blockade of muscarinic (atropine), alpha 1-adrenergic (prazosin), beta-adrenergic (propranolol), H1 (pyrilamine), or H2 (cimetidine) receptors did not alter ergonovine-induced contraction. These data indicate that ergonovine directly contracts canine tracheal smooth muscle as a result of its combination with 5HT receptors. This effect may result in precipitation of an asthmatic attack in susceptible individuals.
Reserpine was found to enhance the cytotoxicity of ACNU on ACNU-resistant C6 glioma (C6/ACNU) cells in vitro. When reserpine was added along with ACNU to the C6/ACNU cells in vitro. When reserpine was added along with ACNU to the C6/ACNU culture in vitro at a concentration of 10 microM, the IC50 of ACNU for C6/ACNU cells decreased to the level of that for C6 cells and ACNU resistance was completely overcome in vitro. Furthermore, intracellular uptake of ACNU increased in both sensitive (C6) and resistant (C6/ACNU) glioma cells when 20 microM reserpine was added to the culture medium. Reserpine (20 microM) enhanced the cellular level of ACNU in C6 cells 1.5-fold and enhanced the level of ACNU in C6/ACNU cells 4-fold. The amount of ACNU incorporated into C6/ACNU cells reached the same level as that incorporated into C6 cells. The enhanced cytotoxicity of ACNU in vitro could be explained by the effective intracellular accumulation of ACNU resulting from the increase of intracellular uptake of ACNU in C6/ACNU cells by reserpine.
The contribution of Na+ and membrane depolarization to biphasic contractions induced by adrenaline were investigated in the smooth muscle of guinea pig vas deferens. Adrenaline (5 X 10(-6) M) produced an initial small contraction (first contraction) followed by a large tonic contraction (second contraction) with subsequent rhythmic activity. The entire response to adrenaline was largely inhibited by phentolamine (5 X 10(-6) M). By adding an appropriate concentration of Mn2+ (2 X 10(-4) M) or nifedipine (3 X 10(-7) M), a Ca2+ blocker, the second contraction was strongly reduced, accompanied by abolishment of the rhythmic contraction, whereas the first contraction was virtually unaffected. However, the first contraction was markedly suppressed by a higher concentration of Mn2+. All contractions produced by adrenaline were greatly reduced in Ca2+-free solution containing 0.5 mM EGTA. By lowering external Na+ concentration, the first contraction was markedly increased without greatly affecting the second contraction. By exposure to Na+-free isotonic high K+ solution, which elicited a greater depolarization of the membrane, the first contraction produced by adrenaline was also greatly potentiated, while the second and rhythmic contractions were eliminated. These results suggest that the adrenaline-evoked first contraction may be due to an influx of membrane bound Ca2+ which is independent of membrane depolarization, while the second (rhythmic) contraction is due to an influx of extracellular Ca2+ which is dependent upon depolarization.
We have recently identified a diabetic patient with marked fasting hyperinsulinemia. Family study revealed that the abnormality was an autosomal dominant trait. High-performance liquid chromatography (HPLC) profile of the patient's serum insulin showed that she had an abnormal insulin in addition to a normal insulin. We have purified her insulin(s) from the specimen of her pancreas, which was biopsied during an operation of cholelithiasis. Insulin was also immunologically purified from the serum of her portal vein. The reverse-phase HPLC analysis revealed that the ratios of normal to abnormal insulin in the pancreas, portal vein, and peripheral vein were 5:4, 4:5, and 1:7, respectively. Radioreceptor assay for insulin using guinea pig kidney membrane revealed that the binding activities of the normal component insulin, the abnormal component insulin and her pancreatic insulin containing both components were 100, 5, and 50% of standard human insulin, respectively. The biological activities of the normal component, the abnormal component and her pancreatic insulin to stimulate glucose oxidation in rat adipocytes were found to be 100, 8, and 60% of standard human insulin, respectively. Analysis of amino acid sequences of the abnormal insulin purified from her pancreas strongly suggested the substitution of leucine for valine at the third position of the A chain, A3 (Val----Leu).
Rat liver contains an ATP-stimulated translocation promoter (ASTP), which is not a receptor and which enhances nuclear binding of activated receptor-glucocorticoid complex in the presence of ATP. Studies were made on changes in ASTP activity under various conditions to elucidate its physiological role in the action of glucocorticoid hormone. ASTP activity in the cytosol fraction increased markedly after adrenalectomy. Conversely, 30 min after a single injection of dexamethasone it decreased and then gradually increased. The increase in ASTP activity after adrenalectomy was inhibited by actinomycin D or cycloheximide. With decrease in ASTP activity in the cytosol fraction after the administration of glucocorticoids, activity appeared in the nuclear fraction 30 min after injection and then decreased. Thus, after the dexamethasone injection, the changes in ASTP activity in the cytosol and nuclei were similar to but not coincident with those in the glucocorticoid receptor. These results suggest, but do not prove, that ASTP is translocated or binds to nuclei with activated receptor-glucocorticoid complexes. From these results, we consider that ASTP may be an integral part of the regulatory mechanism for the action of steroid hormones and may influence specific gene expression by increasing nuclear binding of the activated complex.
A 28 year-old woman was admitted to Jichi Medical School Hospital because of amenorrhea, cold intolerance, easy fatigability and body weight loss. She was pregnant at the age of 26 years. She delivered a 3230 g healthy girl at full term without any complications. However, she did not have any lactation or recurrence of menstruation after the delivery. Serum cortisol was 0.7 micrograms/dl, and plasma adrenocorticotropic hormone (ACTH) was less than 10 pg/ml. Both hormones failed to increase in response to insulin-induced hypoglycemia or exogenous arginine vasopressin. However, serum cortisol and urinary excretion of 17-hydroxycorticosteroids (17-OHCS) were significantly increased by the repeated administration of ACTH. Serum prolactin was 2.2 ng/ml and the level did not rise after the administration of thyrotropin releasing hormone (TRH). Responses of release of adenohypophysial hormones including gonadotropins, growth hormone and thyroid stimulating hormone (TSH) were normal. Serological studies showed an antibody to the pituitary gland which was demonstrated by an indirect immunofluorescence technique. Plain skull X-ray film and brain computerized tomography revealed an empty sella of the normal size. These results indicate the presence of partial deficiency of ACTH and prolactin, and that autoimmune disorders may be involved in the pathogenesis of her hypopituitarism.
Explore the source record for details and available documents.
Explore the source record for details and available documents.