ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1992.tb02243.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1992.tb02244.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

OBJECTIVE We aimed to investigate the pattern of 24‐hour ACTH and cortisol secretion in pitultary‐dependent Cushing's syndrome and to evaluate the pituitary and hypothalamic contributions to the disease.PATIENTS Five women with Cushing's disease (mean age 35±5 (SEM) years) and five normal female controls (mean age 25±2 years) were studied.DESIGN AND MEASUREMENTS Plasma ACTH and cortisol levels were measured every 15 minutes for 24 hours using established IRMA and RIA respectively. ACTH and cortisol mean and trough levels, pulse number and amplitude were calculated using established computer software, programmed to identify ACTH and cortisol peaks.RESULTS Patients with Cushing's disease had a twofold increase in 24‐hour mean cortisol levels and a threefold increase in 24‐hour mean ACTH levels (Cushing's 5.9±1.0, controls 1.9±0.2 pmol/l, P<0.01). This was predominantly mediated by an increase in ACTH pulse amplitude. However, 24‐hour ACTH pulse number was also increased (Cushing's 15±2±2±6, controls 10±6±1±7, P<0±05) due to an increase in pulse number between 1800 and 2400 h. ACTH trough levels were also higher in patients with Cushing's disease (Cushing's 5±3±1±3, controls 2±3±0±2 pmol/I, P<0±05).CONCLUSION Twenty‐four‐hour mean plasma cortisol and ACTH levels are elevated two to three‐fold in patients with Cushing's disease. The Increase in ACTH pulse amplitude suggests a pituitary abnormality in patients with Cushing's disease. However, the increased ACTH pulse frequency together with elevated trough levels is interpreted as Indicating coexisting hypothalamic st

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1992.tb02245.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

OBJECTIVE We wished to analyse the relative value of computerized tomography and magnetic resonance in patients referred for evaluation of pituitary and parasellar lesions.DESIGN We performed a separate evaluation by two independent neuroradiologists of computerized tomography and magnetic resonance images ordered numerically and anonymously, with no clinical data available. PATIENTS We studied 40 patients submitted for hypothalamic‐pituitary study; 31 were carried out preoperatively, of which histological confirmation later became available in 14. The remaining nine patients were evaluated post‐operatively.MEASUREMENTS Over 40 parameters relating to the bony margins, cavernous sinuses, carotid arteries, optic chiasm, suprasellar cisterns, pituitary, pituitary stalk and extension of the lesion were evaluated. These reports were compared with the initial ones offered when the scans were ordered, and with the final diagnosis.RESULTS Concordance between initial computerized tomography and magnetic resonance was observed in 27 cases (67±5%); among the discordant cases computerized tomography showed the lesion in two, magnetic resonance in 10, while in the remaining case reported to harbour a microadenoma on computerized tomography the differential diagnosis between a true TSH‐secreting microadenoma and pituitary resistance to thyroid hormones is still unclear. Both neuroradiologists coincided in their reports in 32 patients (80%); when the initial report was compared with those of the neuroradiologists, concordance was observed with at least one of them in 34 instances (85%). Discordant results were observed principally in microadenomas secreting ACTH or PRL and in delayed puberty. In the eight patients with Cushing's disease (histologically confirmed in six) magnetic resonance was positive in five and computerized tomography in two; the abnormal image correctly identified the side of the lesion at surgery.CONCLUSIONS In patients referred for evaluation of Cushing's syndrome or hyperprolactinaemia (due to microadenomas) or after surgery, magnetic resonance is clearly preferable to computerized tomography. In macroadenomas both scans are equally diagnostic but magnetic resonance offers more information on pituitary morphology and neighbouring structures. Nevertheless, there are cases in which the results of computerized tomography and magnetic resonance will complement each other, since different parameters are analysed with each examination and discordant results are encou

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1992.tb02246.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

OBJECTIVE Hypopituitary adults who were affected during childhood have a below‐average rate of marriage, a rate of unemployment that exceeds national norms, and often indicate dissatisfaction with their life circumstances. We undertook the present study to determine the effects of short stature versus those of pituitary hormone deficiency.DESIGN AND PATIENTS We compared hypopituitary adults (n= 25) with normal short adults (n= 25) who were matched for height, sex, age and socioeconomic status.MEASUREMENTS In these two groups of subjects, we compared the physiological responses to a simulated social stressor, a public speaking task, and we measured the psychometric attributes that are indicators of social assertiveness and extraversion.RESULTS Before, during and after the stress of public speaking, patients with multiple pituitary hormone deficiencies (n= 20) had lower mean systolic and diastolic blood pressures than controls, while patients with isolated growth hormone deficiency (n= 5) were equivalent to controls. The reactivity to stress, assessed using delta scores based on changes in blood pressure and heart rate, was also decreased in multiple hormone deficient patients. Psychometric test results indicated that patients with multiple hormone deficiencies showed lower openness, lower assertiveness, greater neuroticism and a tendency towards less extraversion than did controls. The responses of patients with isolated GH deficiency on the psychometric tests were not statistically different from controls, but the number of subjects in this group (n= 5) was too small to draw conclusions.CONCLUSIONS The impaired cardiovascular responses to stress in patients with multiple hormone deficiencies, compared to short control subjects and to patients with GH deficiency leads us to conclude that factors other than stature and GH are responsible for these observations. The differences might be related to insufficiency of cate‐cholamines or cortisol in the patients with multiple hormone deficiencies. These hormonal deficiencies might also account for the socially inhibited behaviour of these patients. Our results suggest that more attention needs to be directed at preparing hypopituitary patients for the challenges of adulthood. Also, these patients may be helped by more intensive efforts at hormonal replacement in adulth

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1992.tb02247.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

OBJECTIVE The aim was to Investigate the hormone secretory products of a pituitary tumour from a patient with multiple endocrine neoplasia type I (MEN I) utilizing cell culture and Immunoassay techniques.DESIGN Adenoma tissue was enzymically dispersed and established In cell culture. Medium was collected for hormone measurement after 2 days, and also after 24‐hour periods during long‐term culture. In addition, tissue fixed at surgery was analysed by Immunocytochemistry and electron microscopy.PATIENT The subject was a 59‐year‐old male with a clinical history characteristic of familial MEN I syndrome. MEASUREMENTS Pituitary hormones in serum and culture medium were measured by fully characterized radiolmmunoassays.RESULTS Preoperative serum LH and FSH levels were normal, or slightly elevated, and there was a progressively blunted gonadotrophin response to GnRH throughout the 8 years prior to adenomectomy. TRH Induced a small, paradoxical Increase In serum gonadotrophin levels 2 weeks preoperatively. Post‐operative pituitary hormone responses to standard stimulation tests showed an active normal pituitary.In vitro, the pituitary tumour cells secreted only gonadotrophins and glycoprotein hormone α‐subunit. The fixed tumour tissue immunostained for α‐subunit alone, and electron microscopy confirmed the presence of secretory granules with diameters of 100–280 nm. Gonadotrophin secretion continued throughout 77 days in long‐term culture, but whilst LH was released at a steady rate, that of FSH transiently increased between days 29 and 48in vitro.CONCLUSIONS These data demonstrate that a pitultary tumour associated with the MEN I syndrome secreted gon

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1992.tb02248.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

OBJECTIVE We aimed to investigate the mechanisms of hypogonadism which develops after head Injury.DESIGN Pulsatile secretion of LH was studied in subjects 6–10 days after major head Injury.PATIENTS We studied five male subjects admitted with major head injuries and six healthy age‐matched control subjects.MEASUREMENTS During the pulsatility study, LH was measured at 5‐minute intervals for 4 hours and 15‐minute intervals for a further 2 hours. In addition, testosterone and LH were measured on Days 1–5, 14 and after 3–6 months.RESULTS The analysis of pulsatile secretion of LH demonstrated an LH pulse frequency similar to control subjects, but a significantly reduced LH pulse amplitude (P<0.001, fixed threshold method;P<0.02, Detect method). Both testosterone and LH levels were reduced after injury with the nadir occurring on Day 4.CONCLUSIONS Hypogonadism after head Injury is due to defective LH secretion, with normal pulse frequency but a reduced puls

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1992.tb02249.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

OBJECTIVE We wished to investigate the interaction of arginine, GHRH and insulin stress on GH secretion.DESIGN Six healthy, non‐obese volunteers underwent seven separate studes in random order. They received (1) insulin alone at 0 minutes; (2) GHRH alone at 15 minutes; (3) arginine alone at 0–30 minutes; (4) arginine at 0–30 minutes and GHRH at 15 minutes; (5) insulin at 0 minutes and arginine at 0–30 minutes; (6) Insulin at 0 minutes, GHRH at 15 minutes and arginine at 0–30 minutes; (7) Insulin at 0 minutes and GHRH at 15 minutes.MEASUREMENTS GH and PRL were measured from —30 to 150 minutes at Intervals of 15 minutes.RESULTS Arginine increased GH responses to GHRH and decreased GH responses to hypoglycaemia, but this inhibitory effect of arginine was reversed by GHRH.CONCLUSIONS The findings suggest that arglnine‐Induced GH release is mainly mediated by a decrease In somatostatinergic tone, while GH responses to insulin stress are probably mediated by both an increase in hypothalamic GHRH release and Inhlbition of

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1992.tb02250.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

OBJECTIVE We have evaluated the efficacy of percutaneous ethanol Injection as an alternative to surgery and iodlne‐131 treatment in solitary autonomous thyroid adenoma.DESIGN Percutaneous ethanol Injection (0.5–2.8 ml ethanol/ml nodular tissue) was performed under sonographic guidance in 3–5 (1–2 weekly) sessions; a 7.5 MHz linear real‐time scanner (Toshiba, mod. 32B) was used for sonographic studies. The thyroid hormone profile was assessed during treatment and for the next 6 months.PATIENTS Fifty‐six patients (40 females, 16 males, mean age 46.SD 9 years; 30 pretoxic, 26 toxic) were included in the study: their pretreatment technetlum‐99 m thyroid scan showed a single hot nodule with total suppression of extranodular tissue in 45 and near‐total suppression in 11.MEASUREMENTS Thyroid hormones, antithyroglobulin and antiperoxidase antibodies were measured by specific radloimmunoassay, while thyrotrophin was evaluated by ultrasensitive Immunoradiometric assay.RESULTS Apart from a case of transient pyrexia, no relevant adverse effects were observed. A slight thyrold hormone increase was seen in both groups immediately following a treatment. Six months after therapy a biochemical and clinical remission of hyperthyroldism was observed in 18 out of 22 toxic patients (81.8%); a significant increase of TSH levels was seen in both groups (P<0.01). With follow‐up, significant volume shrinkage (P<0.001) as well as structural alterations of the nodule were consistently recorded at sonography; a linear relationship (r= 0.98;P<0.0001) between pretreatment volume and volume reduction was found. At scintiscan, functional activity of extranodular parenchyma was found In 40 out of 56 patients (71.4%), 16/26 (61.5%) In the hyperthyrold group, 24/30 (80.0%) In the pretoxic group.CONCLUSIONS These data confirm that percutaneous ethanol Injection is effective in obtaining functional ablation and in Inducing remission of hyperthyroldism, when present; adverse effect

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1992.tb02251.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

OBJECTIVE We aimed to re‐evaluate the captopril test in the diagnosis of primary hyperaldosteronism.DESIGN Serum aldosterone and plasma renin activity were measured supine prior to and 60, 90, 120 minutes after oral captopril, 25 mg.PATIENTS We have performed this test in ten patients with primary hyperaldosteronism, two with hypertension and secondary hyperaldosteronism and in ten normokalaemic patients with essential hypertension.MEASUREMENTS Validity was assessed by mathematical prediction methods.RESULTS Using a ratio of aldosterone to plasma renin activity>1400 pmol/l per μg/ml/h as a predictor of primary hyperaldosteronism, the captopril test had a sensitivity of 100%, a specificity of 83% and a predictive value of 82% with a 60‐minute post captopril evaluation being sufficient. Nevertheless, this test was only marginally superior to a careful analysis of the supine values where a similar ratio In the presence of a normal or suppressed plasma renin activity predicted primary hyperaldosteronism with a sensitivity also of 100% but a slightly lower specificity of 75% and predictive value of 77%.CONCLUSION Application of the captopril test to patients identified as abnormal by screening confirms all cases of primary hyperaldosteronism but false positive or equivocal results, necessitating further Investigation, may occur In some patients with esssential hyperten

ISSN:0300-0664    

DOI:10.1111/j.1365-2265.1992.tb02252.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY