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Biomedical subjects

A R Hermus

Publications and source records attributed to A R Hermus.

At least 73 records · Page 4Linked to original sources
PubMed1993

Long-term results of two schedules of radioiodine treatment for toxic multinodular goitre.

The long-term effects of two schedules of radioiodine therapy in patients with toxic multinodular goitre were evaluated. Forty-five patients (group A) were treated with low doses and 58 patients (group B) with calculated doses adjusted for thyroid weight (1.85-3.70 MBq/g) and radioactive iodine uptake. Follow-up (mean +/- SEM) was 4.3 +/- 0.2 years and 5.2 +/- 0.3 years, respectively (P > 0.1). At the end of follow-up, hyperthyroidism was successfully reversed in 73% (group A) and 88% (group B). In each group, hypothyroidism was present in 7%. The total dose per gram of thyroid tissue was not significantly different in groups A and B (2.1 +/- 0.2 vs 2.7 +/- 0.2 MBq/g). However, for patients treated with calculated doses the number of 131I administrations was significantly lower (1.3 +/- 0.1) than for patients treated with low doses (2.2 +/- 0.2), and the percentage of patients who were adequately treated with a single dose was more than twice as high (66% in group B versus 27% in group A). Euthyroidism was reached within a significantly shorter time after treatment with calculated doses (median time 0.6 years in group B vs 1.5 years in group A; life table analysis). It is concluded that radioiodine is an effective treatment for toxic multinodular goitre with a low risk of post-treatment hypothyroidism and that calculated (higher) doses appear to be preferable to low doses.

Adult↗
PubMed1993

Long-term follow up of breast cancer patients treated for hypercalcaemia with aminohydroxypropylidene bisphosphate (APD).

No systematic data are available about the long-term follow up of breast cancer patients treated with amino-hydroxypropylidene bisphosphate (APD) for hypercalcaemia and about the results of APD treatment of recurrent hypercalcaemia in these patients. Treatment with intravenous APD (10-15 mg daily until normalization of the serum calcium level) normalized serum calcium in 29 of 31 patients with hypercalcaemia due to advanced breast cancer. Survival in these 29 patients varied between 8 and 693 days (median 140 days) and 7 patients achieved a partial remission or stabilisation of disease during subsequent anti-tumor therapy. In 16 of the 29 patients in whom APD treatment was initially successful, hypercalcaemia recurred after a median period of 65 days. Eleven of these patients received a second course of APD, which was equally successful as the first in terms of percentage of patients with normalization of serum calcium, total dose of APD needed, and duration to normalization of serum calcium. Recurrent hypercalcaemia occurred significantly faster after the second successful APD course (median 17 days) than after the first (median 65 days). When only patients with progressive disease were taken into account, recurrence of hypercalcaemia usually occurred early, both after a first (median 23 days) and after a second successful APD course (median 17 days). Normalization of serum calcium occurred in 4 of 6 patients receiving a third APD course, in all 3 patients receiving a fourth, and in 1 of 2 patients receiving a fifth course.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Regulation of resistance against adjuvant arthritis in the Fisher rat.

Inbred female Lewis (LEW/N) rats develop a severe chronic arthritis in the adjuvant arthritis (AA) model, histocompatible Fisher (F344/N) rats are resistant and germ-free Fishers (GF F344) are again susceptible. In this study we show that the F344 rat can become susceptible to AA, using Mycobacterium tuberculosis (M.tb.) in the powerful adjuvant paraffin oil, instead of mineral oil (Freund's incomplete adjuvant (FIA)). This indicates that the F344 rat does not lack T effector cells. To examine further mechanisms responsible for suppression, we determined the level of plasma corticosterone in response to IL-1 alpha in Lewis, F344 and GF F344 rats. IL-1 alpha induced only low amounts of corticosterone in Lewis rats, but high amounts in both F344 and GF F344 rats. The GF F344 rats are susceptible to AA, but the severity of the disease is reduced compared with Lewis rats. This indicates that corticosterone may be an important mechanism to suppress disease development, but not the only mechanism. In addition we investigated whether T suppressor cells play a role in the resistance of the F344 strain. This was performed by pretreating the animals with the immunomodulating drugs cyclophosphamide (Cy) and cyclosporin A (CsA). We were unable to make the F344 rat susceptible to AA, indicating that active suppression does not play a role in the induction phase of arthritis. This finding is confirmed in adoptive transfer experiments of AA from Lewis to F344 rats. Our data suggest the lack of a strong pre-existing suppression in the F344 rats, and indicate that suppression is generated upon bacterial challenge. Whether suppression is overruled probably depends on the power of adjuvants used and potential control by corticosteroids.

Animals↗
PubMed1993

Unpredictable hypersecretion of cortisol in Cushing's disease: detection by daily salivary cortisol measurements.

A 70-year-old man with mild signs and symptoms of Cushing's syndrome due to an ACTH-secreting pituitary adenoma is described. He had a completely unpredictable pattern of urinary excretion of cortisol; 24 h urine for determination of cortisol excretion was collected daily at home on 725 consecutive days. During this period there were eight episodes in which urinary cortisol excretion exceeded the upper limit of normal. Within these episodes the pattern of cortisol secretion was extremely unpredictable, with cortisol excretion ranging from normal to highly elevated. Using a Cluster Analysis Program 61 pulses of cortisol excretion were detected within the eight periods of cortisol hypersecretion. The interval between two pulses varied from 2 to 12 days. Between the periods of cortisol hypersecretion, urinary cortisol excretion was completely normal, lasting from 4 to 102 days. There was no difference in the clinical expression of Cushing's syndrome between the periods of elevated and normal urinary cortisol excretion. During the last 439 days of the observation, cortisol was also measured in saliva collected at home at 09.00 after an overnight fast. The salivary cortisol pattern closely resembled that of urinary cortisol excretion and there was a significant correlation between salivary cortisol levels and 24 h urinary cortisol excretion in the 24 h after (r = 0.42, p < 0.0001, Spearman) and before saliva collection (r = 0.44, p < 0.0001). On 71% of occasions cortisol peaks in saliva, as detected by the Cluster Analysis Program, coincided with urinary cortisol peaks. We conclude that daily measurement of cortisol in saliva, collected at home, is a convenient and reliable method for detecting intermittent hypercortisolism in patients with Cushing's syndrome.

Adenoma↗
PubMed1993

Thermoregulation and afterdrop during hypothermia in patients with poikilothermia.

The pathophysiology of afterdrop of core temperature during rewarming in patients with induced or accidental hypothermia remains controversial. We studied the effect of cooling and rewarming in four female patients with acquired poikilothermia and in four normal females. Exposure to cold air (16.5 degrees C) induced shivering and adequate vasoconstriction in normal individuals, without a fall in rectal temperature (Tr; 36.3 +/- 0.2 degrees C [mean +/- SD]); subsequent heating (40 degrees C) induced a rise in Tr to 37.0 +/- 0.3 degrees C and generalized sweating. The four patients all had spontaneous hypothermia (Tr 34.1 +/- 0.9 degrees C) before cooling. Tr decreased by 0.3-0.9 degrees C during cold exposure, and a marked afterdrop of Tr (0.3-0.5 degrees C) occurred during rewarming: this did not occur in normal individuals. Cooling failed to induce shivering and vasoconstriction in three patients. No patient showed visible sweating during heating despite a Tr of up to 38.0-38.5 degrees C and skin temperature of up to 37.7-38.5 degrees C. The basal metabolic rate was decreased by 71-82% in all patients during steady-state hypothermia and remained lowered during normothermia in two patients. We conclude that during hypothermia three of the four patients showed severe disorders of peripheral vasomotor function and shivering response. These data provide evidence for thermal conduction as the major mechanism of afterdrop during hypothermia.

Adult↗
PubMed1992

Adrenocortical function: an indicator of severity of disease and survival in chronic critically ill patients.

Plasma cortisol levels and modified Apache II (Apache IIm-stay) severity of disease scores were determined at weekly intervals in 159 patients who were treated for at least 7 days at the Critical Care Unit of our hospital. The mean (+/- SD) plasma cortisol level (0.60 +/- 0.28 mumol/l) was clearly elevated in these patients. The highest plasma cortisol levels were measured in patients treated with vasoactive drugs (0.76 +/- 0.39 mumol/l). Non-survivors (n = 36) had a significantly higher mean plasma cortisol level and Apache IIm-stay score than survivors (respectively 0.78 +/- 0.40 vs. 0.54 +/- 0.21 mumol/l; p less than 0.0003 and 12.6 +/- 4.8 vs. 7.3 +/- 4.1; p less than 0.0001). A significant correlation was found between the individual weekly plasma cortisol levels and the Apache IIm-stay scores (r = 0.41; p less than 0.0001), especially in the subgroup of patients, who never received glucocorticoids during their stay at the ICU (r = 0.51; p less than 0.0001). During the 14-month study period only two patients showed a clinical picture of adrenocortical insufficiency and a blunted response of cortisol to 0.25 mg synthetic ACTH(1-24). In conclusion, our data suggest that a high plasma cortisol level, like a high Apache IIm-stay score, indicates severity of disease and poor survival in critically ill patients. De novo adrenocortical insufficiency is rare and therefore routine screening of adrenocortical function is superfluous.

Adolescent↗
PubMed1992

Dose intensity of chemotherapy with cyclophosphamide, methotrexate and 5-fluorouracil in the elderly with advanced breast cancer.

Toxicity and results of two different dose levels of chemotherapy with cyclophosphamide, methotrexate and 5-fluorouracil (CMF) in older (greater than 70 years) patients with advanced breast cancer were evaluated in a prospective (non-randomised) study. During the first three courses of chemotherapy dose reduction for haematological toxicity was necessary in all of 10 and 8 of 13 patients treated with an intended dose of 100% and 75% of standard dose CMF, respectively. The median percentages of CMF, administered during the first three courses were about 75% in both groups of patients corresponding with a median dose intensity of 72% (range 49-87%) and 64% (range 36-78%) for patients of the 100% and 75% dose group, respectively. In 34 younger postmenopausal women (mean age 57 years) treated in our institution for advanced breast cancer the median percentages of CMF in the second and third course were 86% and 84%, respectively with a median dose intensity during the three courses of 82%. Dose reductions of CMF and bone marrow toxicity, though interdependent, were statistically significantly correlated with the endogenous creatinine clearance, but not with age. 1 patient died during severe leukopenia and thrombocytopenia. Non-haematological side effects were most pronounced in the 100% group. Results of therapy in both groups of patients were about equal and compared well with those of CMF therapy in general. It is advised that the dose of CMF in patients above 70 years should not exceed 75% of standard dose. Further dose reduction of methotrexate in case of severe renal failure is required.

Age Factors↗
PubMed1992

Electrocardiographic changes during steady mild hypothermia and normothermia in patients with poikilothermia.

1. ECG changes observed in short-term induced and accidental hypothermia are well known. To assess the influence of steady-state spontaneous hypothermia on the ECG, we subjected four patients with acquired poikilothermia (severe thermolability) to 24 h ECG recording, exercise testing and thermal stress. 2. Twenty-four hour Holter monitoring showed a significant reduction in heart rate and a prolongation of the QT interval during steady-state mild hypothermia (rectal temperature 33.9 +/- 0.7 degrees C, mean +/- SD) compared with during normothermia; no significant changes occurred in the PR interval, QRS complex and QTc interval (QT interval corrected for heart rate). 3. Unlike during normothermia, during steady hypothermia atrioventricular Wenckebach blocks were observed in two patients, whereas another patient showed markedly more atrioventricular Wenckebach blocks during hypothermia. 4. During steady hypothermia the heart rate variability was significantly enhanced in comparison with normothermia. 5. Exercise tolerance was similar during mild hypothermia and normothermia. 6. Heat exposure (ambient temperature 40 degrees C) induced significantly greater changes in rectal temperature, heart rate and PR interval, QRS complex and QT interval in the patients than in the control subjects (n = 8). 7. The present study reveals that even mild steady spontaneous hypothermia can elicit ECG changes, presumably mediated by relatively enhanced cardiac vagal tone. Hence, spontaneous abnormalities in core temperature should be taken into account in interpreting the ECG in clinical practice.

Adult↗
PubMed1992

Interleukin-1-induced nonspecific resistance to bacterial infection in mice is not mediated by glucocorticosteroids.

Preexposure to a low dose of interleukin-1 (IL-1; 3 to 30 micrograms/kg) 24 h before a lethal gram-negative bacterial infection prolonged survival in normal and granulocytopenic mice. To examine whether this protective effect is mediated by glucocorticosteroids, we first measured corticosterone concentrations in mice after administration of 80 and 800 ng of IL-1. IL-1 induced a dose-dependent increase in corticosterone levels in plasma. Next, the corticosterone peak induced by a protective dose of IL-1 (800 ng) was simulated by administration of synthetic human adrenocorticotropic hormone 1-24 (ACTH) in normal and neutropenic mice. Although corticosterone levels induced by pretreatment with IL-1 or ACTH were virtually identical, the ACTH-induced corticosterone peak was not associated with protection against Klebsiella pneumoniae infection in normal mice and Pseudomonas aeruginosa infection in neutropenic mice. This indicates that the protective effect of IL-1 pretreatment against gram-negative bacterial infection is not mediated by elevated levels of glucocorticosteroids. In addition, we found that plasma corticosterone concentrations during K. pneumoniae infection were significantly lower after pretreatment with IL-1 than after pretreatment with ACTH or vehicle, probably reflecting the better physical condition of IL-1-treated mice.

Animals↗
PubMed1992

Chronic infusion of TNF-alpha reduces plasma T4 binding without affecting pituitary-thyroid activity in rats.

In the present study the effects of continuous administration of tumor necrosis factor-alpha (TNF-alpha), in a dose not affecting body temperature and food intake, on pituitary-thyroid function of rats were investigated. Male rats, bearing a venous catheter to allow repeated blood sampling, were intraperitoneally equipped with osmotic minipumps that continuously delivered recombinant human TNF-alpha (8.0 micrograms/day ip) or saline for 7 days. Infusion of TNF-alpha resulted in a significant decrease of plasma total thyroxine (T4) levels during days 2-5 of infusion as compared with the levels in saline-infused rats. This suppression of plasma T4 concentrations was caused by a decreased binding of T4 in plasma, as indicated by an increased percentage of free T4. TNF-alpha infusion did not significantly affect free T4 levels in plasma nor basal and thyrotropin-releasing hormone-stimulated TSH levels. The decreased binding of T4 was, at least partially, caused by a reduction of T4-binding prealbumin (TBPA) levels in plasma, which were significantly reduced during the first 3 days of TNF-alpha infusion. Plasma levels of free fatty acids were not affected by TNF-alpha. TNF-alpha treatment did not influence the plasma 3,5,3'-triiodothyronine (T3)-to-T4 ratio nor hepatic 5'-deiodinase activity. Plasma reverse T3 levels remained undetectable both in control and TNF-alpha-treated rats. Taken together, our findings indicate that chronic infusion of rats with TNF-alpha in a subpyrogenic and subanorectic dose induces a transient decrease of plasma T4 binding without affecting pituitary-thyroid activity and peripheral thyroid hormone metabolism.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Continuous infusion of interleukin-1 beta in rats induces a profound fall in plasma levels of cholesterol and triglycerides.

During infectious diseases, striking alterations in plasma concentrations of cholesterol (hypocholesterolemia) and triglycerides (hypertriglyceridemia) may occur. It has been suggested that interleukin-1 is a mediator of these alterations. We studied the effects of continuous administration of recombinant human interleukin-1 beta (rhIL-1 beta) on plasma levels of cholesterol and triglycerides. A total of 42 rats were equipped with minipumps loaded with either rhIL-1 beta (delivery rate of 0.5, 2.0, or 4.0 micrograms/day i.p. for 1 week) or saline. After 1 day of treatment with rhIL-1 beta, plasma cholesterol levels had not changed. On day 2 a remarkable decrease of plasma cholesterol levels was observed in rats treated with 2.0 micrograms rhIL-1 beta/day (1.49 +/- 0.13 versus 2.23 +/- 0.08 mmol/l, p less than 0.005; rhIL-1 beta versus saline) or 4.0 micrograms rhIL-1 beta/day (1.46 +/- 0.04 versus 2.18 +/- 0.04 mmol/l,p less than 0.0005). This decrease persisted until the end of the experiment and occurred in all major lipoprotein fractions. Triglycerides in plasma (and in very low density lipoprotein) decreased almost concomitantly with plasma cholesterol, although to a lesser degree. Infusion of 2.0 micrograms rhIL-1 beta/day did not affect either cholesterol esterification or total postheparin lipolytic activity in plasma. Long-term infusion with 4.0 micrograms rhIL-1 beta/day induced prolonged fever, whereas at the lower doses temperatures were elevated only the first 2 days. rhIL-1 beta at a dose of 2.0 and 4.0 micrograms/day induced a transient decrease of food intake and a suppression of body weight gain.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Chronic stimulation of the pituitary-adrenal axis in rats by interleukin-1 beta infusion: in vivo and in vitro studies.

It has been shown that acute administration of interleukin-1 (IL-1) to rats elicits a transitory increase in plasma ACTH and corticosterone (B) levels. To investigate the effects of chronic administration of IL-1 on plasma ACTH and B levels, in the present study rats were equipped with Alzet osmotic minipumps loaded with either IL-1 (delivery rate 0.5, 2.0, or 4.0 micrograms/24 h, ip, for 1 week) or saline. At the end of the treatment the rats were decapitated, the adrenals were weighed, and the in vitro release of beta-endorphin (beta E) by the anterior pituitary and that of B by the adrenal gland were measured. Continuous administration of 2.0 and 4.0 micrograms IL-1/24 h resulted in a persistent increase in plasma ACTH and B concentrations compared to the levels in saline-infused rats, with peak levels on the first day of administration. In addition, adrenal weights of IL-1 rats were significantly higher than those of saline rats. The 4.0-micrograms IL-1/day in vivo treatment induced an increase in spontaneous in vitro secretion of beta E and B, while the in vitro responses of the pituitary (to CRF) and the adrenal (to ACTH) of animals treated in vivo with IL-1 were significantly diminished. IL-1 at a dose of 0.5 microgram failed to affect plasma ACTH and B values, adrenal weight, and in vitro beta E and B secretion. Chronic infusion of rats with 4.0 micrograms IL-1/day induced prolonged fever, whereas at lower doses of IL-1 (2.0 and 0.5 micrograms), temperatures were elevated only on the first 2 days of infusion. IL-1 at doses of 2.0 and 4.0 micrograms/day induced suppression of body weight gain on the first 2 days of the treatment period compared to saline treatment. Plasma norepinephrine and/or epinephrine concentrations were raised only on day 1 of the 2.0- and 4.0-micrograms IL-1 experiments. Thus, the observed effects of IL-1 on the hypothalamo-pituitary-adrenal axis probably do not result merely from stress induced by the treatment. Taken together, our data show the potential of IL-1 to induce a dose-dependent and long term activation of the pituitary-adrenal axis.

Adrenal Glands↗
PubMed1992

TSH-dependent production of T4 and T3 by metastases of a thyroid carcinoma.

A patient with T4 and T3 production by metastases of a follicular thyroid carcinoma leading to TSH suppression is described. During a period of three years, plasma T4, T3 and TSH levels were measured in the substitution-free periods before the successive iodine-131 retention measurements and iodine-131 therapies, when the patient was at least two weeks without thyroid hormones. From the presented data it can be derived that the production of thyroid hormones by metastases was enhanced by endogenous TSH.

Adenocarcinoma↗
PubMed1991

Poikilothermia in man: pathophysiology and clinical implications.

Poikilothermia, the inability to maintain a constant core temperature independent of ambient temperature, markedly influences both the mental and physical function of affected patients; furthermore, prolonged hypothermia can induce numerous complications. To establish the pathophysiology of thermoregulation underlying poikilothermia in man, we compared 4 women with acquired poikilothermia, with 9 female control subjects. The activity of the main thermoregulatory effector mechanisms was assessed in a thermoneutral environment, and during subsequent cold stress and heat exposure. At thermoneutrality the patients had a significantly lower rectal temperature and resting metabolic rate compared with the controls; no patient showed peripheral vasoconstriction or shivering. Cooling revealed markedly reduced peripheral vasoconstriction in 3 patients and failure of the metabolic response in 2 patients; unlike controls, no patient exhibited shivering. Heat challenge revealed severely reduced capacity for heat dissipation in all patients. We conclude that in patients with poikilothermia, the mechanisms for both heat conservation and heat dissipation are seriously attenuated. Careful monitoring of the core temperature and adequate measures to maintain normothermia are of great importance in patients with poikilothermia in order to provide adequate treatment, improve the quality of life, and prevent serious complications.

Adipose Tissue↗
PubMed1991

Aseptic bone necrosis in patients on glucocorticoid replacement therapy.

The incidence of aseptic bone necrosis in 167 patients on glucocorticoid replacement therapy in our hospital was found to be 2.4% (4 patients). The diagnosis was made 16 months to five years after initiation of the therapy. A review of eight other cases reported in the literature is presented. The incidence of aseptic bone necrosis in patients on glucocorticoid replacement therapy seems much higher than might be expected. It is suggested that the dose of glucocorticoid substitution therapy be established individually at the lowest acceptable level.

Adult↗
PubMed1991

Effects of steady hypothermia and normothermia on the electrocardiogram in human poikilothermia.

The electrocardiographic changes observed in (short-term) induced and accidental hypothermia are well known. We studied the electrocardiographic effects of steady mild hypothermia in 4 female patients with poikilothermia. 24h Holter recording revealed during mild hypothermia significantly decreased heart rate and prolongation of the QT interval in comparison with normothermia. During hypothermia the short-term heart rate variability and the circadian rhythm of heart rate variability were significantly higher than during normothermia. We conclude that in our patients even mild steady hypothermia induces electrocardiographic alterations. In patients with disorders of thermoregulation one should be on the alert for cardiovascular complications, especially in cold climates.

Adult↗
PubMed1990

Cytokines and the hypothalamic-pituitary-adrenal axis.

After administration of the cytokines interleukin 1 (IL1), tumor necrosis factor (TNF), interleukin 2 and interleukin 6 to laboratory animals or humans, plasma levels of glucocorticoids are elevated. This effect is mediated by activation of the hypothalamic-pituitary unit. IL1 and TNF inhibit aldosterone production by rat adrenocortical cells in vitro and stimulate renin release by rat renal cortical cells. Administration of IL1 or TNF in rats suppresses hypothalamic-pituitary-thyroid function, whereas IL1 acts at the level of the brain and the gonads to interfere with gonadotropin and sex steroid secretion. During stimulation of the immune system (e.g. during infectious diseases), peculiar alterations in hormone secretion occur (hypercortisolism, hyperreninemic hypoaldosteronism, euthyroid sick syndrome, hypogonadism). The role of cytokines in these alterations remains to be established.

Animals↗