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S Naomi

Publications and source records attributed to S Naomi.

At least 37 records · Page 2Linked to original sources
PubMed1990

Role of carbohydrate moiety of IL-5. Effect of tunicamycin on the glycosylation of IL-5 and the biologic activity of deglycosylated IL-5.

IL-5 is a T cell-derived lymphokine that induces B cell growth and differentiation in murine systems. In this study, we examined the role of carbohydrate moiety of IL-5 in the expression of biological function. IL-5 polypeptides translated in Xenopus oocytes were heterogeneous in terms of isoelectric point (pI 4.7 to 8.0) and m.w. (45,000 to 60,000 under nonreducing conditions) and yielded m.w. of 25,000 to 30,000 under reducing conditions. Treatment of rIL-5 with N-glycanase under reducing conditions yielded an IL-5 monomer of m.w. 12,000 to 14,000. Furthermore, deglycosylated rIL-5 that had been translated in the presence of tunicamycin showed very limited heterogeneity by two-dimensional gel electrophoresis (first dimension, nonequilibrium pH gradient electrophoresis; second dimension, SDS-PAGE). The m.w. was 27,000 to 28,000 under non-reducing conditions and migrated to m.w. 13,000 to 14,000 under reducing conditions. These results indicate that IL-5 is a glycoprotein carrying the N-glycosidically-linked carbohydrates. Treatment of IL-5 with sialidase caused the decrease in the heterogeneity in isoelectric point of IL-5. Deglycosylated rIL-5 that had been obtained from tunicamycin-treated oocytes could bind to IL-5-responding cells (T88-M), which express both high- and low-affinity IL-5 receptors, as efficient as intact rIL-5 under high-affinity conditions. Scatchard plot analysis of equilibrium binding of 35S-labeled rIL-5 to T88-M cells revealed that the dissociation constants (Kd) of glycosylated rIL-5 and deglycosylated rIL-5 were 127 pM and 110 pM, respectively. IL-5 activities determined by both B cell growth and differentiation assays were not affected by deglycosylation. These results indicate that N-linked glycoside moiety of IL-5 molecules may not play an essential role in the expression of its activity.

Animals↗
PubMed1990

Localization of aldosterone-producing adenoma: venous sampling in primary aldosteronism.

Adrenal venous sampling of blood was performed for nine patients with aldosterone-producing adenoma (APA). Measurement of adrenal venous aldosterone is useful for localization of APA but difficult, because catheterization of the right adrenal vein is not easy, and the blood is diluted by nonadrenal flow. To solve these problems, levels of aldosterone (A; ng/dl) and cortisol (C; micrograms/dl) were measured in samples from the left adrenal vein (LAV) and the inferior vena cava (IVC), and the LAV A/C and (LAV A/C)/(IVC A/C) ratios were calculated. These ratios were also obtained for 16 patients with essential hypertension. The adenoma could be localized in three of the nine cases by the measurement of aldosterone alone, but the use of a LAV A/C ratio greater than 5 x 10(-3) and a (LAV A/C)/(IVA A/C) ratio less than 1.0 as criteria separated the patients into those with a left APA, right APA, or essential hypertension. Consequently, adrenal venous sampling and the calculation of these ratios enables preoperative localization of APA with more accuracy, especially when the tumor is small or the result of CT and adrenal scintigraphy is not consistent.

Adenoma↗
PubMed1990

Plasma atrial natriuretic peptide in patients with Graves' disease.

In order to clarify the effect of thyroid hormone on the plasma atrial natriuretic peptide (ANP) concentration, 14 patients with Graves' disease and 6 normal control subjects were studied. They were all under constant sodium intake because dietary sodium is known to affect the amount of plasma ANP. Sodium intake remained constant at 171 mEq daily for five consecutive days at which time the ANP concentration was measured. Graves' disease patients were tested both before and after surgery. The preoperative, hyperthyroid ANP level concentration in Graves' disease patients was 6.7 +/- 2.3 fmol/ml compared to a significantly lower level of 4.2 +/- 1.4 fmol/in normal control subjects. Seven days after surgery when Graves' disease patients became euthyroid their ANP markedly decreased to 4.2 +/- 2.9 fmol/ml. In the present study we were able to confirm that under a constant sodium diet, high plasma ANP in patients with Graves' disease was reduced after surgery when they became euthyroid. Results also suggest that high circulating ANP might play an important role in sodium and water metabolism and hemodynamic changes in hyperthyroidism.

Age Factors↗
PubMed1989

[Determination of plasma alpha human atrial natriuretic polypeptide using monoclonal antibodies in patients with chronic renal failure].

To clarify the molecular nature and dynamics of circulating alpha human atrial natriuretic polypeptide (alpha hANP) in chronic renal disease, the plasma concentrations of alpha hANP were determined by radioimmunoassays using two distinct monoclonal antibodies (MoAbs). One MoAb (10B1) recognized N-terminus of alpha hANP, while the other (C351) recognized the ring structure. The preliminary studies revealed a close correlation (r = 0.97, p less than 0.0001) between plasma alpha hANP measured with 10B1 and C351 MoAbs, supporting the theory that the main circulating form is alpha hANP(1-28). Therefore, the more sensitive radioimmunoassay using MoAb (C351) was used in the present studies. The plasma alpha hANP was 3.8 +/- 1.7 (mean +/- SD) in healthy subjects, 2.7 +/- 1.4 fmol/ml in patients with chronic glomerulonephritis without renal failure, 16.2 +/- 16.8 fmol/ml in patients with chronic renal failure, and 24.3 +/- 10.5 fmol/ml in patients under maintenance hemodialysis. Thus, the elevation of plasma alpha hANP was related to the stages of renal damage. Although the plasma alpha hANP in 18 patients under maintenance hemodialysis declined significantly (p less than 0.01) after hemodialysis, their levels (17.9 +/- 9.0 fmol/ml) after hemodialysis were still higher than those in healthy subjects. On the other hand, a positive correlation (r = 0.65, p less than 0.05) between alpha hANP and creatinine in blood was found only in the group of chronic renal failure before maintenance hemodialysis. These results suggest that an impaired metabolism of alpha hANP in the kidney might play an important role in the elevation of plasma alpha hANP as well as the stimulation of alpha hANP secretion caused by the expansion of extracellular fluid.

Adult↗
PubMed1988

[Lateralisation of aldosterone-producing adenoma in primary aldosteronism].

Four lateralizing methods were carried out in 14 patients with primary aldosteronism (PA): ultrasonography, CT scan, adrenal scintiscan and determination of adrenal venous aldosterone levels. In all cases, unilateral aldosterone-producing adenomas were verified by surgery. Of four lateralizing methods, determination of adrenal venous aldosterone, in spite of high diagnostic value, has two big problems: difficulty in selective catheterization of right adrenal vein and dilution of adrenal vein efflux from non-adrenal sources. To solve these problems, cortisol (C, micrograms/dl) levels along with aldosterone (A, ng/dl) were determined in samples from the left adrenal vein (LAV) and the inferior vena cava (IVC) in 8 patients with PA, and the (LAV A/C)/(IVC A/C) ratio was calculated. That ratio was also obtained in 7 patients with other types of hypertension for comparison. Accuracy of lateralisation by ultrasonography, CT scan and adrenal scintiscan was 23%, 64% and 69% respectively, in the first studies. Those rates changed to 23%, 93% and 85% when the second studies were performed. Venous blood was obtained from both adrenal veins in 46% (6/13), while lateralisation of adenoma was also predicted in 46% (6/13) by the measurement of aldosterone concentrations alone. On the other hand, (LAV A/C)/(IVC A/C) ratios were 3.54-6.98 in the cases of left APA, 0.15-0.98 in those of right APA and 1.10-2.86 in cases of other types of hypertension. There was no overlap of ratios among the three groups, resulting in correct prediction of lateralisation in all cases (8/8) of APA.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗
PubMed1988

Receptors for T cell-replacing factor/interleukin 5. Specificity, quantitation, and its implication.

T cell-replacing factor (TRF)/IL-5 is a glycosylated polypeptide that acts as a key factor for B cell growth and differentiation. Since IL-5 action is probably mediated by specific cell surface receptor(s), we have characterized the binding of IL-5 to cells using biosynthetically [35S]methionine-labeled IL-5 and 125I-IL-5 that had been prepared using Bolton-Hunter reagent. The radiolabeled IL-5 binds specifically to BCL1-B20 (in vitro line) (a murine chronic B cell leukemic cell line previously shown to differentiate into IgM-secreting cells in response to IL-5) within 10 min at 37 degrees C. There are two classes of binding sites with high affinity (Kd = 66 pM) and low affinity (Kd = 12 nM) for IL-5 and an average number of binding sites for high affinity and for low affinity were 400 and 7,500 per cell, respectively. The specificity of binding of radiolabeled IL-5 has been confirmed by demonstrating that only unlabeled IL-5 and anti-IL-5 mAb but not by IL-1, IL-2, IL-3, IFN-gamma, and GM-CSF inhibit radiolabeled IL-5 binding to BCL1-B20 cells. Treatment of surface-bound radiolabeled IL-5 with bivalent crosslinkers identified a membrane polypeptide of Mr 46,500 to which IL-5 is crosslinked. A variety of cell types have been surveyed for the capacity to bind specifically radiolabeled IL-5 with high affinity. BCL1 cells MOPC104E (murine myeloma cell line) expressed IL-5-R, whereas BAL. 17 and L10 A (B cell lymphoma) did not. T cell line, mastocytoma cell line, or macrophage tumor cell line did not display detectable levels of IL-5-R. were hardly detectable on normal resting B cells but were expressed on LPS-activated B cells, fitting the function of IL-5 that acts on activated B cells for their differentiation into Ig-secreting cells. Intriguingly, early B cell lines (J-87 and T-88) that grow in the presence of IL-5 expressed significant but low numbers of high-affinity binding sites for IL-5. The biological effects of IL-5 were mediated by high-affinity binding sites. The identification and characterization of IL-5-R should provide new insight into the apparent diverse biological activities of IL-5.

Affinity Labels↗
PubMed1988

The effect of low and high NaCl diets on oral glucose tolerance.

The effects of low and high NaCl diets on plasma glucose and insulin responses to glucose ingestion were investigated in 15 patients with essential hypertension. Oral glucose (75 g) tolerance tests were carried out while patients were taking diets with low (2 g/day) and high (20 g/day) NaCl content. Fasting plasma glucose and insulin levels were both significantly lower during ingestion of the high NaCl diet (p less than 0.05). After glucose ingestion, the incremental areas under the two hour plasma glucose and insulin curves were significantly smaller during ingestion of the high NaCl diet (glucose p less than 0.005 and insulin p less than 0.025). These findings that low NaCl diets increase the glycemic response to glucose loads suggest that use of NaCl restriction for the treatment of essential hypertension may not always be desirable.

Adult↗
PubMed1988

[Salt sensitivity and central dopaminergic activity in patients with essential hypertension].

The pathophysiological role of the central dopaminergic mechanism in human essential hypertension (EH) is still unknown. We studied on the relationship between the dopaminergic activity and the salt-sensitivity. Twenty three hospitalized patients with EH were divided into the salt-sensitive group (SS, n = 12) or non salt-sensitive group (NSS, n = 11) by their responses whether they caused more than 8% increase in mean blood pressure (MBP) when the dietary salt was increased from 2g/day to 20g/day for 7 days of each. The change of central dopaminergic activity by the salt load was evaluated by the decrement of plasma prolactin (PRL) response to small dosage (25 micrograms) of thyrotropin releasing hormone. The mean percent change of PRL response by the salt load in the SS group was -6.5 +/- 8.3% (mean +/- SEM), which was significantly lower than 26.8 +/- 5.5% in the NSS group (p less than 0.01). There was a significant negative correlation between the percent changes of PRL response and the percent changes of MBP by the salt load (r = -0.448, p less than 0.05). These results suggested that the rise in blood pressure by salt load in SS patients with EH might be due to a reduced activity of the central dopaminergic mechanism.

Adult↗
PubMed1988

A sensitive radioimmunoassay of alpha human atrial natriuretic polypeptide using monoclonal antibody recognizing human form ring structure.

A monoclonal antibody (C351) against alpha human atrial natriuretic polypeptide (alpha hANP) recognizing human form ring structure was established and applied to a radioimmunoassay of plasma alpha hANP. The minimum detectable amount in terms of 10% radioligand displacement relative to zero dose were 0.28 fmol/tube, corresponding to 0.7 fmol/ml in plasma after extraction using Sep-Pak C18 cartridges. When the mean plasma levels at recumbent position in fasted morning were compared in 10 young (less than 30 years) and 10 elderly (greater than or equal to 50 years) healthy subjects taking normal sodium diet, it was slightly higher in the latter (3.2 +/- 0.4 vs 4.7 +/- 0.5 fmol/ml, mean +/- SE, p less than 0.05). After i.v. infusion of hypertonic saline (2.5% NaCl) at a rate of 0.24 ml/kg/min for 20 min in 6 normal subjects (26 to 35 years), it was increased from 4.1 +/- 0.4 to 5.9 +/- 0.7 fmol/ml (p less than 0.01). In 6 patients with essential hypertension (34 to 57 years), it was elevated with high salt intake, i.e. 3.3 +/- 0.3, 3.9 +/- 1.03 and 7.6 +/- 1.5 fmol/ml under 34, 170 and 340 mEq NaCl/day for 7 days, respectively. From these results, the radioimmunoassay of plasma IR-alpha hANP using MAb C351 seems to be quite suitable to detect rather small changes at low plasma concentrations and to investigate a physiological importance of alpha hANP in man.

Adult↗
PubMed1988

Is salt sensitivity in essential hypertension affected by ageing?

To investigate the question of whether the salt sensitivity of blood pressure in human essential hypertension is affected by ageing, the salt-sensitivity index was determined in 54 hospitalized patients with essential hypertension, aged 26-67 years (mean +/- s.d. 46.9 +/- 9.5 years) as well as plasma inhibition of Na+,K+-ATPase (sodium-pump inhibitor), erythrocyte sodium and potassium concentrations and fractional excretion of lithium. The salt-sensitivity index was calculated as the percentage change in mean blood pressure when the dietary sodium content was increased from 34 mmol/day (low sodium) to 340 mmol/day (high sodium) for 8 days each. Despite wide range of ages, age showed no correlation with the salt-sensitivity index, the sodium-pump inhibitor, the erythrocyte Na+:K+ ratio or fractional excretion of lithium. Furthermore, the distribution of the salt-sensitivity index did not differ between older (greater than or equal to 45 years old) and younger (less than 45 years old) age groups. In contrast, the distribution of this index was correlated positively with the change in sodium pump inhibition induced by a sodium load (r = 0.415, P less than 0.05) and negatively with the fractional excretion of lithium (r = -0.725, P less than 0.01). The erythrocyte Na+:K+ ratio tended to be higher in patients with a salt-sensitivity index of 10% than in those with an index of less than 5%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

Production and characterization of monoclonal antibodies against amino-terminus of human alpha-atrial natriuretic polypeptide.

Monoclonal antibodies directed against human, alpha-atrial natriuretic polypeptide (alpha-ANP; Human, 1-28) were obtained by somatic cell fusion between P3-X63-Ag8.653 myeloma cells and spleen cells from a BALB/c mouse immunized with human, alpha-ANP selectively coupled to keyhole limpet hemocyanin. From the analysis of polyclonal sera with respect to determinant specificity before the fusion, the strategy was primarily used to pick up monoclonal antibody specific for the N-terminal residues of human, alpha-ANP. Screening of antibodies in the hybridoma culture supernatants were performed by binding to iodinated synthetic human, alpha-ANP. Two stable clones producing anti-human, alpha-ANP antibodies, designated 13A1 and 10B1, were obtained by the limiting dilution technique. The ability of ANP(Rat, 1-28) to inhibit binding of 125I-human, alpha-ANP to these antibodies was almost equipotent to ANP(human, 1-28). However, ANP fragments (Human, 7-28) and (18-28) did not compete the binding completely. These results suggest that both 13A1 and 10B1 monoclonal antibodies can specifically recognized N-terminus of human, alpha-ANP, and may be a useful tool to investigate receptor binding of human, alpha-ANP by the antagonizing effect.

Amino Acid Sequence↗
PubMed1987

The effect of iopanoic acid on thyrotropin secretion in patients with cirrhosis of the liver.

Ten patients with liver cirrhosis and six normal subjects were studied to evaluate the effect of iopanoic acid (IA) on thyrotropin secretion. A thyrotropin-releasing-hormone (TRH) test was performed before and 5 days after IA administration (single oral dose of 3 g). After IA administration, a significant increase in TSH response to TRH was observed in normal subjects. In cirrhotics, however, it did not significantly increase after IA administration. The serum T3 and T3/TBG ratio were significantly decreased and the serum T4 and T4/TBG ratio were increased after IA administration in normal subjects and cirrhotics. There was no significant difference in the % decrease in serum T3, % increase in serum T4 or other thyroid hormone parameters including TSH in IA induced TSH responders (R) and non-responders (NR). However, r-T3 before and after IA in R was higher than those in NR. The values for hepatic function tests such as serum albumin, prothrombin time, 45 minutes retention rate of bromsulphalein (BSP 45 min) and the cholinesterase (ChE) level in R were not different from those of NR. These results suggested that in cirrhotics, abnormal regulation of the hypothalamo-pituitary system might exist.

Adult↗
PubMed1987

Effects of sodium intake on the captopril test for primary aldosteronism.

The validity of the captopril test for primary aldosteronism (PA) was tested in patients with surgically verified PA (n = 12) or essential hypertension (EHT, n = 20) with different levels of sodium intakes. The patients were scheduled on 7 days each of three regimes of the prepared diet containing 34, 120 and 340 mEq of sodium chloride per day, and the captopril test was repeated in each period. For the test, captopril (50 mg) was administered orally at 9:00 A.M. after 1 hour of rest in a supine position, and venous blood samples were obtained before and 90 min after drug administration. Plasma aldosterone concentration (PAC; ng/dl) and plasma renin activity (PRA; ng/ml/h) were measured by radioimmunoassay. Under the three different sodium intakes, a PAC/PRA ratio greater than 20 at 90 min after captopril administration was sufficiently sensitive (0.95, 19/20) and specific (0.92, 55/60) to identify PA. Similarly, PA was associated with a PAC above 15 ng/dl 90 min after captopril. There were no complaints associated with the antihypertensive effects of the drug even when patients were sodium-restricted. These results confirmed that the captopril test is safe and useful for screening out-patients for PA, independent of individual differences in sodium intake.

Adult↗
PubMed1987

Assay of a circulating sodium pump inhibitor in patients with essential hypertension and normotensive subjects.

The plasma levels of a sodium pump inhibitor (Na+ PI) were measured by a modified method of Hamlyn et al, using dog kidney Na+, K+-ATPase. When the level of Na+ PI was expressed as the % inhibition of the enzyme and compared with that of a control solution, it was found to be 9.0 +/- 0.7% in 43 untreated patients with essential hypertension. This was significantly higher than 5.0 +/- 0.4% for 56 normotensive subjects (p less than 0.01). Male patients with essential hypertension showed the highest mean value of 10.5 +/- 1.1%, disclosing an apparent sex difference in the patient group (p less than 0.01). Only in female patients was there a significant positive correlation between the inhibitor's level and the mean blood pressure (r = 0.649, p less than 0.01). These results provided additional evidence for increased Na+ PI in the plasma of patients with essential hypertension, which might bear an important role in the pathogenesis of the disease.

Adult↗
PubMed1986

Pheochromocytoma associated with adrenocortical adenoma: case report and literature review.

The case of a 60-year-old woman with pheochromocytoma and concomitant adrenocortical adenoma in the same gland is presented. She complained of episodic headache, palpitation, nausea, vomiting and sweating. Physical examination revealed that the patient has generalized obesity, wet skin and paroxysmal hypertension, but no signs of Cushing's syndrome. Elevated levels of urinary noradrenaline, adrenaline and total metanephrine were sequentially observed. In addition, urinary 17-OHCS was also slightly elevated, but plasma cortisol was normal and suppressed after oral administration of 0.5 mg of dexamethasone. Abdominal echography and CT scanning demonstrated a left adrenal tumor, which took up both 131I-meta-iodobenzylguanidine and 75Se-scintadoren in the same region. A left adrenalectomy was performed and the tumor was found to consist of two parts, pheochromocytoma (2.5 X 2.5 X 2.5 cm) and cortical adenoma (2.5 X 3 X 5 cm). A total of 23 reported cases showing evidence of hyperfunction of the adrenal cortex and the medulla were noted. So far as we know, this patient was the second case of pheochromocytoma with adrenocortical adenoma in Japan.

Adenoma↗
PubMed1985

Clinical evaluation of the captopril screening test for primary aldosteronism.

In order to investigate the validity of angiotensin converting enzyme inhibition with captopril as a screening test for primary aldosteronism (PA), 50 mg of captopril were administered orally to 7 patients with PA, 17 with essential hypertension (EH), 5 with renovascular hypertension (RVH), 2 with renoparenchymal hypertension (RH) and 8 normal volunteers. The plasma aldosterone concentration (PAC) was suppressed to less than 15 ng/dl in all of the EH, RVH and RH patients and normal subjects 90 min after administration of captopril, but not suppressed in 6 of 7 patients with PA. In addition, the plasma renin activity (PRA) was increased to greater than 1 ng/ml/h in 10 of 17 patients with EH and in all with RVH, RH and the normal controls, but to less than that in 6 of 7 PA and the remaining EH patients. The PAC to PRA ratio after captopril was greater than 20 in all patients with PA, while it remained below 20 in EH, RVH and RH patients and normal controls. From these results, we conclude that the PAC to PRA ratio in the captopril administration test is a simple and useful tool to detect PA in hypertensive patients. In addition, the test has a great advantage in that it can be safely applied to outpatients with relatively severe hypertension.

Adult↗