Plasma digoxin levels in anuric patients and normal subjects taking digitoxin

Summary Plasma digoxin suspected to be elevated in anuric patients taking digitoxin was determined by radioimmunoassay in 15 anuric patients and 15 normal persons subjected to 0.1 mg digitoxin therapy per day. All plasma digoxin values from the anuric patients and the normal subjects were far below the lower limit of the therapeutic range of plasma digoxin. There existed no difference between the digoxin values determined in anuric patients and subjects with normal renal function; in both groups there was a scatter of digoxin values about the cross reaction line between digitoxin and digoxin antibody. It is concluded from the results that digoxin retention in anuric patients taking digitoxin plays an insignificant role; thus, the pharmacological effect is mediated by digitoxin itself.Supported by the Deutschen Forschungsgemeinschaft concerning SFB 89 Kardiologie Göttingen     

Effects of secretin on parathyroid hormone and calcium in normal subjects, patients with hyperparathyroidism and patients with gastrinoma

In vitro studies have demonstrated that secretin can stimulate the release of parathyroid hormone (PTH), but reports concerning its effects on PTH and calcium in vivo are contradictory. To examine this question further, a bolus injection of secretin (75 IU) was given to 12 normal subjects and 10 patients with primary hyperparathyroidism (HPT). Six of the patients had multiple endocrine neoplasia and five had endocrine pancreatic tumours (EPT). Three normocalcaemic patients with EPT were also included in the study. The mean serum gastrin level rose significantly (from 19 to 40 pmol/l, p less than 0.01) within 15 min of secretin injection in the normal subjects. HPT patients without EPT had a somewhat higher mean basal level of gastrin (39 pmol/l, p less than 0.05 compared with controls), but it did not increase significantly after the secretin bolus. In six EPT patients the gastrin concentrations rose by more than 300 pmol/l. Although secretin had a biological capacity to release gastrin, it had no discernible effects on either serum PTH or serum calcium in any of the groups studied. Nor were any changes in PTH or calcium observed when secretin was given as a continuous infusion (3 IU/kg/h) over 90 min. Thus, our data do not support the concept that secretin, in vivo, is a secretagogue of PTH.     

Tubular reabsorption of calcium in normal and hypercalciuric subjects

Tubular reabsorption and excretion of calcium were studied at different levels of filtered calcium by means of calcium infusion in normal and hypercalciuric subjects and in patients with idiopathic nephrolithiasis.Calcium reabsorption and excretion rose linearly with filtered load and in no case was a maximum tubular reabsorptive capacity for calcium reached.No decrease in tubular reabsorption of calcium was found in hypercalciuric as compared with normocalciuric subjects, and no difference in tubular reabsorption was found between patients with idiopathic nephrolithiasis and normal subjects.Calcium excretion and reabsorption calculated from the endogenous creatinine clearance during calcium infusion were virtually identical with the corresponding values calculated from the inulin clearance.     

Plasma fibronectin in normal subjects and in various disease states.

Plasma fibronectin was determined in 121 normal adults and in 149 patients. Fibronectin levels in normals were strongly influenced by sex and age. The mean value of the protein in cancer patients did not differ from that in normal controls; however, patients with cryofibrinogenaemia or extensive liver metastases had lower values whereas those with obstructive jaundice due to pancreatic carcinoma had higher values than normal controls. Fibronectin levels were greatly increased in patients with primary biliary cirrhosis and moderately elevated in nephrotic syndrome. In patients with severe infection or sepsis, plasma fibronectin did not show a consistent pattern. Patients with overt disseminated intravascular coagulation, irrespective of its cause, had the lowest plasma fibronectin concentrations.     

Control of breathing in normal subjects and in patients with chronic airflow obstruction

In order to assess ventilatory control in patients with chronic airflow obstruction (CAO), the present study was carried out in nine patients with chronic obstructive pulmonary disease (COPD), eight asthmatics and nine normal subjects. We analysed the components of the respiratory control system at three levels: neural, assessed by diaphragmatic electromyography (EMGd), muscular, assessed by mouth occlusion pressure (P0.1), and ventilatory, assessed by mean inspiratory flow (VT/TI). EMGd was recorded by surface electrodes. During a CO2 rebreathing test, patients showed a normal or greater EMGd response slope (EMGdS), while for a given degree of EMGdS, P0.1 response slope (P0.1S) was found to be significantly reduced; in contrast, for a given degree of P0.1S, VT/TI response slope (VT/TIS) was found to be significantly reduced in COPD patients only. These data show that, compared to normal subjects, patients with CAO have a normal or increased neural component of the respiratory activity (EMGdS) and a relatively lower neuromuscular coupling (P0.1S/EMGdS). Probably due to different parenchymal and airway involvement, musculoventilatory transfer (VT/TIS/P0.1S) was found to be reduced in COPD patients but not in asthmatics. A complementary study, showing a good agreement between surface and oesophageal EMGd seems to confirm that surface EMGd is a useful and promising tool for clinical investigation.     

Effects of acute hypercalcaemia on blood pressure in subjects with and without parathyroid hormone secretion

AIM: Acute hypercalcaemia increases the blood pressure, but the mechanism is uncertain. It may partly be the result of the concomitant fall in parathyroid hormone (PTH) secretion as PTH has been reported to have a vasodilator effect. To elucidate this, we infused calcium intravenously in subjects with and without PTH secretion. METHODS: Seven thyroparathyroidectomized subjects with undetectable PTH levels and 10 controls were studied twice, once with a calcium clamp technique that increased plasma ionized calcium in two steps of 0.1 mmol L(-1), each step lasting 60 min, and once with a placebo infusion. RESULTS: On the placebo day, blood pressure and all other variables were unaffected in both groups. On the calcium day, systolic blood pressure increased gradually and significantly from end of baseline till end of the calcium infusion in the controls (123.5 +/- 19.8 and 134.2 +/- 17.6 mmHg, P < 0.004) but not in the thyroparathyroidectomized subjects (124.9 +/- 15.7 and 126.0 +/- 20.6 mmHg, P = ns). Serum PTH levels fell promptly in the controls, and in both groups there was a significant increase in serum phosphate. The diastolic blood pressure and pulse rate, and the plasma adrenaline and noradrenaline, plasma renin activity, and serum aldosterone levels were unaffected by the calcium infusion. CONCLUSION: During acute hypercalcaemia the blood pressure increase appears unrelated to catecholamine secretion and the renin-aldosterone system, whereas the fall in PTH secretion may play a contributory role.     

Plasma tryptophan to large neutral amino acid ratios in depressed and normal subjects

The ratios of total and free plasma tryptophan to the sum of five large neutral amino acids (LNAAs) were found to be significantly lower in a group of 16 depressed inpatients compared to nine normal subjects after oral loading with L-tryptophan. The group differences in these ratios were significant before, and 2 weeks after starting treatment with a tricyclic antidepressant. Plasma tryptophan ratios and severity of depression were not significantly correlated.     

Circulating basophils in normal subjects and in subjects with hay fever

The relationship of hay fever symptoms and changes in the number of circulating basophils was studied in 12 subjects clinically sensitive only to ragweed and in 10 nonatopic subjects before, during, and after the ragweed season. Total white blood counts, absolute basophil counts, and symptom scores were recorded twice weekly from mid-June through October, 1974, and compared with the ragweed pollen count. The results indicated that the absolute and relative number of basophils were significantly elevated (p < 0.001) in the hay fever group when symptoms occurred. As the symptom score of the allergic group increased during the ragweed season, the number of basophils also increased, only to decrease to control values when symptoms subsided. The basophil counts of the atopic group were significantly higher than those of the nonatopic group during the control periods. The nonatopic group also showed a significant elevation of basophils during the ragweed season, but to a much lesser extent than the atopic group. It is concluded that: (1) subjects with symptomatic hay fever have a significantly elevated absolute and relative basophil count which correlates with the exacerbation and remission of symptoms; (2) nonatopic subjects also have a small but significant elevation of basophils during the ragweed season; and (3) the elevation of basophils in the atopic group during symptoms is significantly greater than in the nonatopic group during the ragweed season.     

The metabolism of C9 in normal subjects and in patients with autoimmune disease

The metabolism of the ninth component of complement (C9) was studied in eight healthy subjects and nine patients with autoimmune disease, including seven with systemic lupus erythematosus (SLE) and one each with mesangial IgA nephropathy and mixed essential cryoglobulinaemia. In normal subjects the metabolic parameters (mean ± s.d.) were: fractional catabolic rate (FCR): 2.92 ± 0.36%/h, plasma half-life (T_1/2): 42.5 ± 6.7 h, and extravascular/intravascular distribution ratio (EV/IV): 0.56 ± 0.12. In patients the FCR was 3.38 ± 0.70%/h, the T_1/2 was 37.6 ± 10.2 h, and the EV/IV was 0.55 ± 0.19. Patients with reduced total serum haemolytic activity (i.e. CH₅₀ < 68% of normal human serum (NHS), n = 7) had significantly higher FCR (3.57 ± 0.67%/h) and shorter T_1/2 (33.5 ± 6.8 h) than the control group (both P< 0.05). The plasma concentration of the terminal complement complex (i.e. soluble TCC or SC5b-9) was higher in patients (median (range): 515 (300–1879 μg/l)) than in normal subjects (313 (229–402 μg/l); P< 0.01) and showed a positive correlation with the FCR of C9 (r =0.61, P< 0.01). Plasma C9 production rate was also greater in patients (0.11 ± 0.05 mg/kg per h) compared with control subjects (0.07 ± 0.03 mg/kg per h, P< 0.05), and was associated with a higher C9 concentration in patients’ sera (76 ± 13 mg/lversus 61 ± 14 mg/l, P< 0.05). These results demonstrate that C9 is rapidly metabolized in normal humans and that hypercatabolism occurs in patients with autoimmune disease and complement activation. This was despite the presence of normal or elevated serum C9 levels and normal compartmental distribution.     

偏执型精神分裂症病人与正常人脑电图向量分析

目的 :用向量分析法处理脑电图 ,为脑电图研究提供一个新的手段。方法 :将 94例偏执型精神分裂症病人 (病人组 )与 35例正常人 (对照组 )的脑电向量分析结果进行比较。结果 :病人组中 6 9例异常 ,2 5例正常。对照组中 ,1例异常 ,34例正常。结论 :脑电信息流的向量分析技术 ,对精神病人的临床诊断有重要价值。     

The effect of diurnal variation on total plasma calcium concentration in normal subjects

In 12 normal subjects plasma calcium and phosphorus concentrations were estimated during a normal working day. In the individual subjects fluctuations from the fasting values occurred during the period of study, but at no time during that period did the mean values differ significantly from the fasting plasma calcium or phosphorus concentrations. In three of the subjects the study was repeated while fasting during a normal working day. In these subjects the fluctuations in both plasma calcium and phosphorus concentrations were less than during a normal day while taking meals, and there was evidence of a diurnal variation in the plasma phosphorus concentration.