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Biomedical subjects

G Kahaly

Publications and source records attributed to G Kahaly.

At least 55 records · Page 3Linked to original sources
PubMed1994

[Cardiopulmonary stress in hyperthyroidism].

Spiroergometry might be applicable to detect alterations of cardiopulmonary functions related to hyperthyroidism. Thus, cardiac and respiratory changes as well as work capacity in hyperthroid female patients were to be assessed with the help of the Cardiopulmonal Exercise Test System. Twelve female hyperthyroid patients with Graves' disease of whom all were controlled in euthyroidism, were examined. Eighteen euthyroid female patients in whom intracardiac catheter examination ruled out cardiopulmonary disease served as controls. The anaerobic threshold was determined by means of the V-slope method. An echocardiography was performed in all patients. Ergometry was performed in a semisupine position using a continuous ramp protocol of 20 watt/min. A markedly reduced work capacity, and a high heart rate in rest and exercise were found. In the ratio heart rate/oxygen uptake a lower rise (p = 0.001) due to a decreased growth in the heart rate was noticed. Regarding the pulmonary system a decreased tidal volume in hyperthyroidism (p = 0.021), and a higher breathing frequency (p = 0.003) were recognized, as well as an impaired oxygen consumption, in comparison with the euthyroid state. Also, echocardiographically an increased cardiac index (p = 0.008) and a markedly reduced stroke volume (p = 0.005) in comparison to the control group were observed. Heart rate, work capacity, oxygen uptake, and the ratio heart rate to oxygen uptake were normalized in euthyroidism. With the help of the CPX-System noninvasive measure of marked cardiopulmonary changes in hyperthyroidism are possible, especially the lower growth of the heart rate in exercise, which might be the limiting factor of work capacity.

Adult↗
PubMed1994

[Color duplex ultrasound findings in patients with endocrine orbitopathy].

UNLABELLED: Color Doppler imaging makes it possible for the first time to assess the blood flow velocity of orbital vessels. Especially in Graves disease, with its increase of orbital contents, this technique allows detection of changes in the perfusion of retrobulbar arteries and veins. We examined 23 patients (19 female, 4 male, average age 47.9 years) with thyroid ophthalmopathy using color Doppler imaging. Central retinal artery and vein, posterior ciliary arteries, vortex veins, superior orbital vein and ophthalmic artery were located and their Doppler spectra analysed. Results were compared with observations recorded in a control group consisting of 105 healthy volunteers. The thicknesses of extraocular muscles were measured echographically. RESULTS: There was no significant difference in blood flow velocity in central retinal artery and vein, posterior ciliary arteries and vortex veins between patients with Graves disease and the control group. The maximal blood flow velocity in superior orbital vein was significantly decreased (P = 0.01 on right eye, P = 0.04 on left eye). There was a slight correlation between reduced venous outflow in the superior orbital vein and the severity of the disease (r = 0.52 on right eye, r = 0.5 on left eye). CONCLUSION: Color Doppler imaging is a new, noninvasive technique that could be used to examine patients with thyroid ophthalmopathy. Reduced venous outflow may contribute to exophthalmus by creating perivenous edema and consequent swelling of orbital fat.

Adult↗
PubMed1993

Retrobulbar adipocytes and humoral immunity in Graves' ophthalmopathy.

As CT and MR-imaging revealed an enlargement of retrobulbar fat tissue in patients with Graves' ophthalmopathy, the role of the retrobulbar adipocytes in the pathogenesis of this disorder remains to be elucidated. To evaluate the in vitro influence of humoral immunity on retrobulbar adipose tissue, the effects of IgG and sera from 56 euthyroid ophthalmopathy patients and 53 controls on both porcine and human (patients' and controls') retrobulbar adipocytes were measured by means of several assays: An enzyme-linked immunosorbent assay was employed to reveal specific binding of antibodies to the adipocytes. Metabolic activity was determined by means of a colorimetric dimethyl thiazolium-diphenyl-tetrazolium bromide test which quantifies the activity of mitochondrial dehydrogenases; cell proliferation was measured by incorporation of [3H]-thymidine in 24 h, and activities of adipocyte specific enzymes, such as membrane-bound lipoprotein lipase and 1-glycerol-3-phosphate-dehydrogenase were determined. By means of these specific enzyme tests no distinctions could be made between patients and controls. Furthermore, a significant difference between patients' (untreated and treated) and controls' IgG to bind to, to activate or to stimulate the proliferation of porcine or human (patients' and controls') retrobulbar adipocytes could not be detected under the employed experimental conditions. The effects of patients' heat-inactivated and non-inactivated sera were indistinguishable from those of the controls. Incubation with autologous sera, however, led to an activation of the retrobulbar adipocytes which was higher than the median caused by the patients' group and that engendered by incubation with autologous IgG.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipocytes↗
PubMed1993

Glycosaminoglycan antibodies in endocrine ophthalmopathy.

An increased accumulation of glycosaminoglycans (GAG) in the orbita has been reported in endocrine ophthalmopathy (EO). In this study we investigated whether antibodies directed against GAG are present in the sera of 52 EO patients and 47 healthy controls. Three out of 52 patients exhibited low titers of antinuclear antibodies and all patients were negative for antibodies against extractable nuclear antigens. Isotype IgG antibodies were detected by means of an ELISA using hyaluronic acid and dermatan sulfate as antigens. Values were expressed as optical density at 405 nm. In comparison to the control group (0.445, 0.364, 0.588; median, 25th, 75th percentile) significantly (p < 0.001) higher hyaluronic acid antibody levels were found in EO patients (0.626, 0.473, 0.801). Untreated patients had significantly higher hyaluronic acid antibody values compared to controls (0.770 vs 0.437, median, p < 0.005). Thyroid status or antithyroid treatment did not influence binding of hyaluronic acid antibodies. When screening for dermatan sulfate antibodies no such difference could be observed between patients and controls. Thus, the detection of GAG antibodies in EO patients emphasizes the important role of glycosaminoglycans in the pathogenesis of thyroid eye disease.

Adolescent↗
PubMed1993

[Selective blood sampling from the sinus petrosus inferior: a comparison of CRF and TRH stimulation].

In 10 patients with hypophyseal Cushing microadenomas, selective bilateral sampling from the inferior petrosal sinuses was performed and the effect of stimulation by iv TRH and CRF was compared. On the side of the microadenoma. ACTH concentration rose from 650 +/- 242 pg/ml to 2712 +/- 843 pg/ml following injection of CRF and 2025 +/- 242 pg/ml after TRH. Contralateral values were 165 +/- 79 pg/ml, 490 +/- 200 pg/ml and 165 +/- 72 pg/ml respectively. Prolactin concentration on the side of the adenoma was 98 +/- 49 ng/ml before stimulation, 236 +/- 62 ng/ml after CRF and 747 +/- 168 ng/ml after TRH. Contralateral concentration was 22 +/- 10 ng/ml, 64 +/- 19 ng/ml respectively. Sampling localised all adenomas correctly, whereas contrast-enhanced MRT diagnosed only four adenomas.

Adenoma↗
PubMed1992

Relation of endocrine and cardiac findings in acromegalics.

Cardiac involvement in 32 acromegalics was related to endocrine parameters, clinical score and duration of the disease as well as compared to that of 50 controls free of cardiac disease. Stress ECG, 24h Holter monitoring and echocardiography revealed that supraventricular premature complexes did not occur more often in acromegalics than in controls, both prevalence and severity of ventricular arrhythmia, however, were higher in patients compared to controls: 15/32 (48%) acromegalics had complex ventricular arrhythmia as compared with 6/50 (12%) normal subjects (p less than 0.01). Repetitive ventricular arrhythmia was manifest in 10/32 (31%) patients but only in 4/50 (8%) controls (p less than 0.01). Furthermore, frequency of ventricular premature complexes increased with duration of acromegaly (p less than 0.01), the severity of the former being correlated with left ventricular mass and with clinical activity score (p less than 0.01). No correlation, however, was found between the degree of ventricular arrhythmia and hormone levels. Left ventricular muscle mass was increased (p less than 0.02) due to concentric hypertrophy. Thus, compared to controls, acromegalics show more frequent and complex ventricular arrhythmia and left ventricular hypertrophy. Duration of the disease rather than hormone levels seems to be relevant for these pathological changes.

Acromegaly↗
PubMed1992

Arrhythmia profile in acromegaly.

In a controlled study, the cardiac involvement and arrhythmia profile of 32 patients with acromegaly were correlated with endocrine parameters (somatomedine C, growth hormone), clinical score and duration of the disease. Data were compared with those of 50 controls free of cardiac disease. Stress ECG, 24 h Holter monitoring and echocardiography were performed. Supraventricular premature complexes occurred no more often in acromegalics than in controls. Both prevalence and severity of ventricular arrhythmia, however, were significantly higher in patients compared to controls (P less than 0.01). 15/32 (48%) acromegalic patients had complex ventricular arrhythmias (Lown III-IV) as compared with 6/50 (12%) normal subjects (P less than 0.01). Repetitive ventricular arrhythmias (Lown IV a/b) occurred in 10/32 (31%) patients, but only in 4/50 (8%) controls (P less than 0.01). Furthermore, the frequency of ventricular premature complexes increased with duration of acromegaly (P less than 0.01). No correlation was found between the severity of ventricular arrhythmia and hormone levels. Left ventricular muscle mass was significantly increased (285 +/- 139 g, P less than 0.02) due to concentric hypertrophy. Severity of ventricular arrhythmias correlated with left ventricular mass and with clinical activity score (P less than 0.01). Thus, compared to controls, acromegalic patients show more frequent and complex ventricular arrhythmias and left ventricular hypertrophy. Duration of the disease rather than hormone levels seems to be relevant for these pathological changes.

Acromegaly↗
PubMed1992

Humoral immunity and retrobulbar fibroblasts in endocrine ophthalmopathy.

The exact role of retrobulbar fibroblasts in the immunopathogenesis of endocrine ophthalmopathy still remains to be elucidated. To evaluate the in vitro influence of humoral immunity on retrobulbar fibroblasts, the effects of immunoglobulin G as well as of the sera of 50 euthyroid patients with endocrine ophthalmopathy and 30 controls on both porcine and human (patients' and controls') retrobulbar fibroblasts were measured by means of several assays: a colorimetric test involving a heterocyclic chemical, a tetrazolium bromide, was applied to quantify the activity of mitochondrial dehydrogenases; the incorporation of 3H-thymidine was determined as a sensitive parameter for cell proliferation, and an enzyme-linked immunosorbent assay was to reveal specific binding of antibodies to the cells. There was consistently no significant difference between patients' (untreated or treated) and controls' IgG to bind to, to activate or to stimulate the proliferation of porcine and human (patients and controls) retrobulbar fibroblasts. The effects of patients' heat-inactivated and non-inactivated sera were indistinguishable from those of the controls. Incubation of autologous sera, however, led to an activation of retrobulbar fibroblasts which was both higher than the median caused by the patients' group and that engendered by incubation of autologous IgG. Yet, a significant role that humoral immunity might play directly on retrobulbar fibroblasts could not be detected in the experiments conducted in this study.

Adult↗
PubMed1992

In vitro synthesis of glycosaminoglycans in endocrine ophthalmopathy.

The effects of humoral and cell-mediated immunity on the glycosaminoglycan synthesis of retrobulbar fibroblasts was evaluated in patients with endocrine ophthalmopathy. After incubation with IgG and sera, secreted glycosaminoglycans, radiolabeled with D-6-3H-glucosamine and 35sulfate, were precipitated with cetylpyridinium chloride and ethanol. Hyaluronic acid synthesis of human retrobulbar fibroblasts after incubation with sera and IgG and after co-culture with lymphocytes was assessed by means of a radiometric test. Patients' IgG, compared to controls', accounted for a higher secretory stimulation of porcine retrobulbar fibroblasts (as measured by cetylpyridinium chloride precipitation) after 24 and 48 h. Contrasting with 24 h incubation time, glycosaminoglycan values after 48 h were increased two to threefold. Patients' and controls' sera caused earlier and stronger, yet indistinguishable glycosaminoglycan production. Non-sulfated hyaluronic acid was the preponderant glycosaminoglycan secreted into the media by retrobulbar fibroblasts. As assessed with the radiometric test, incubation with patients' and controls' sera and IgG did not reveal a significant difference in stimulating the hyaluronic synthesis of patients' and controls' retrobulbar fibroblasts. When measuring the hyaluronic acid synthesis of controls' and patients' retrobulbar fibroblasts after co-cultivation of lymphocytes, however, patients' lymphocytes had a marked ability to increase the hyaluronic acid concentration compared to controls' lymphocytes. The hyaluronic acid concentration after incubation of a patient's retrobulbar fibroblasts with autologous lymphocytes was markedly more elevated than the intrinsic hyaluronic acid production of retrobulbar fibroblasts.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Glycosaminoglycans in thyroid-associated ophthalmopathy.

Glycosaminoglycan (GAG) accumulation in the retrobulbar space of patients with thyroid-associated ophthalmopathy (TAO) has been documented in a number of immunohistochemical studies. In order to gain further insight into possible immunopathogenic mechanisms, the influence of humoral immunity on retrobulbar fibroblasts (RF) as GAG producing cells as well as on GAGs themselves was investigated. The effect of lymphocytes on hyaluronic acid (HA) synthesis of RF as well as in turn the influence of RF on lymphocytes were evaluated. In search of methods which would facilitate management of patients with TAO and allow assessment of disease activity, GAGs were determined in both urine and plasma. Immunoglobulin G (IgG) of patients with TAO were found to markedly stimulate the 3H-GAG secretion of RF. Patients with TAO exhibited significantly greater antibody values directed against HA than controls. Preliminary results concerning the influence of lymphocytes on RF indicate a tendency for patients' lymphocytes to increase the synthesis of HA. Furthermore, these lymphocytes in turn were stimulated more by irradiated autologous RF than by irradiated heterologous RF. Urine and plasma GAG determination proved to be suitable for the routine assessment of disease activity and outcome of therapy. In conclusion, GAGs seem to play an important role in the pathogenesis of the disease and their measurement may provide aid to the endocrinological evaluation of patients with TAO.

Antibody Formation↗
PubMed1991

Relationship of eye muscle antibodies with HLA phenotypes and thyroid-stimulating immunoglobulins in endocrine orbitopathy.

The relationship between endocrine orbitopathy and Graves' hyperthyroidism is still not clarified. The purpose of this study was to elucidate the incidence of eye muscle antibodies and the relationship with HLA phenotypes and thyroid antibodies in 65 patients with endocrine orbitopathy classes 1-5. Both bovine and abdominal muscles were used as antigens in ELISA systems in which IgG and IgM antibodies were assayed. Before starting the immunosuppressant therapy, 46/65 patients (71%) showed a positive result for eye muscle antibodies. Those patients with an active disease had such antibodies more frequently. Where the ophthalmopathy was of recent onset IgM antibodies were found, whereas patients with chronic disease were mostly IgG-Ab positive. No association was found either with HLA phenotypes (B8, DR3) or with antibodies directed against thyroglobulin, thyroid microsomes, and the TSH receptor measured as thyroid-stimulating immunoglobulins. Furthermore, there was no correlation between ophthalmopathy class and optic muscle antibody-binding activity. There was no relation between the degree of exophthalmos and eye muscle, thyroid-stimulating, antithyroglobulin, or antithyroid microsomal antibodies. These results suggest that, although very closely related, endocrine orbitopathy and Graves' hyperthyroidism are separate, organ-specific autoimmune diseases.

Adolescent↗