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Thyroid hormone preparations, especially thyroxine, are widely used either at replacement doses to correct hypothyroidism or at suppressive doses to abolish thyrotropin (thyroid-stimulating hormone) secretion in patients with differentiated thyroid carcinoma after total thyroidectomy or with diffuse/ nodular nontoxic goitre. In order to suppress thyrotropin secretion, it is necessary to administer slightly supraphysiological doses of thyroxine. Possible adverse effects of this therapy include cardiovascular changes (shortening of systolic time intervals, increased frequency of atrial premature beats and, possibly, left ventricular hypertrophy) and bone changes (reduced bone density and bone mass), but the risk of these adverse effects can be minimised by carefully monitoring serum free thyroxine and free liothyronine (triiodothyronine) measurements and adjusting the dosage accordingly. Thionamides [thiamazole (methimazole), carbimazole, propylthiouracil] are the most widely used antithyroid drugs. They are given for long periods of time and cause adverse effects in 3 to 5% of patients. In most cases, adverse effects are minor and transient (e.g. skin rash, itching, mild leucopenia). The most dangerous effect is agranulocytosis, which occurs in 0.1 to 0.5% of patients. This life-threatening condition can now be effectively treated by granulocyte colony-stimulating factor administration. Other major adverse effects (aplastic anaemia, thrombocytopenia, lupus erythematosus-like syndrome, vasculitis) are exceedingly rare.

We studied the effectiveness of orally administered thyrotropin-releasing hormone (TRH) (40 mg/day) for 10 days against placebo in 11 patients with hereditary ataxias (HA). All patients completed the trial and none reported any noticeable side effects. A clinical rating scale for inherited ataxias and the Northwestern University Disability Scale for clinical disability showed no significant variation over the duration of the study. Manual dexterity, studied with the peg board test, showed a significant improvement after TRH compared with basal values, which persisted after washout. Eye movement alterations, as revealed by electroculography were reduced after TRH and washout when compared with placebo and basal scores. Hormonal monitoring showed only a transitory effect on the hypothalamus-hypophysis-thyroid axis. These results demonstrate that orally administered TRH has a mild but significant effect only on some cerebellar symptoms in HA.

Quality of life (QoL) may be affected in acromegalic patients, although the role of disease activity is still unsettled. The aim of the study was to assess the QoL of acromegalic patients with a specific questionnaire (ACROQOL). ACROQOL was evaluated in a prospective study (at baseline, at 6 and 24 months) in 23 active untreated acromegalic patients. Control of acromegaly was defined by normal age-matched serum IGF-I concentrations. Patient groups were defined as controlled or uncontrolled at 6 months and at 24 months: controlled or uncontrolled during the entire study period (ACRO(CC) or ACRO(NC), respectively) or uncontrolled at 6 months and controlled thereafter (ACRO(C)). At 6 months, ACROQOL scores improved globally (from 54.3+/-21 to 65.1+/-19, p=0.04) as did subdomains and were inversely related to IGF-I variation (r=-0.50, p=0.052). At 24 months, ACROQOL improved globally (from 54.3+/-21 to 65.7+/-18.0, p=0.04) and this was also seen in the appearance subdomains; however, no correlation was revealed between variation of serum IGF-I concentrations and changes in ACROQOL total score (r=0.008, p=0.87). ACROQOL scores did not significantly change in ACRO(NC) (p=0.310) and in ACRO(C) (p=0.583), whereas it improved globally (from 42.1+/-22.1 to 58.8+/-16.04, p=0.021) and in psychological subdomains in ACRO(CC); however, it reflected the improvement occurred within the first 6 months of disease control. In conclusion, successful treatment, which normalizes disease activity, improves QoL in acromegaly in the short term. However, the lack of correlation between the ACROQOL score in the long term might suggest that factors other than serum IGF-I participate in the well-being of acromegalic patients; however, due to the small sample size, our results need to be confirmed in larger studies.

Microvessel density (MVD) represents a measure of angiogenesis and may be used as an indicator of neoplastic aggressiveness. Vascular endothelial growth factor (VEGF) plays a pivotal role as angiogenic promoter by stimulating endothelial cell proliferation and migration and enhancing vascular permeability. The aim of this study was to investigate MVD and VEGF expression in human pituitary adenomas and normal pituitary gland tissues by immunohistochemistry, and to correlate data with clinical characteristics. Fragments from 46 pituitary adenomas (18 non-functioning, 12 ACTH-secreting, 12 GH-secreting, 4 PRL-secreting) and 19 specimens of normal anterior pituitary gland obtained at surgery were evaluated. MVD in normal anterior pituitary was significantly higher than in tumors (69.2 +/- 28.5 vs 29.3 +/- 19.7; p0.0001). Within adenomas, no difference was found in MVD when different histotype, size, sex, age, rate of recurrence or medical pre-surgical treatment were considered. The degree of vascularity was somewhat related only to clinical invasiveness, as evaluated by pre-surgical MRI grading (grade 0 p0.05 vs grade 1 and vs grade 2). No statistically significant difference in VEGF expression was found between normal tissue and adenomas and among tumors of different histotype (p = 0.3978). Size, sex, age, rate of recurrence and medical pre-surgical treatment did not influence VEGF expression. No correlation was found between MVD and VEGF expression. In conclusion, MVD was reduced in pituitary adenomas with respect to normal gland. VEGF expression is however well preserved in adenomas and this might contribute to adequate tumoral vascular supply with complex mechanisms other than endothelial cells proliferation.

Color flow doppler sonography (CFDS) is a powerful technique which displays tissue blood flow and vascularity. Hyperthyroidism due to Graves’ disease is characterized by variable degrees of increased blood flow at CFDS. The purpose of this study was to evaluate CFDS patterns in five women with thyrotoxicosis factitia, a condition due to surreptitious ingestion of excess thyroid hormone. Diagnosis was supported by the finding of elevated free thyroxine (FT4), ranging 24.2–67.6 pmol/L (normal values: 8.3–20.5), elevated free triiodothyronine (FT3), ranging 9.9–26.7 pmol/L (normal values: 3.8–8.4), undetectable thyrotropin (TSH), absent anti-thyroid antibodies, undetectable serum thyroglobulin (Tg) concentrations, very low/suppressed thyroidal radioiodine uptake and normal/low urinary iodine excretion. Moreover, all patients admitted thyroid hormone pills intake. All patients had normal thyroid volume and echogenicity at conventional sonography (mean estimated volume, 9.4 ml, range, 6–11 ml), and absent hypervascularity or minimal intrathyroidal vascular spots at CFDS. The peak systolic velocity (PSV) was at the lower limit of normal values (mean, 4 cm/sec, range 3–5 cm/sec). Twenty-six women with untreated Graves’ disease had an increase in the mean PSV, (mean 12.9 cm/sec, range 8–20, p

Peroxisome proliferator activated receptor (PPAR)gamma plays a pivotal role in regulating adipocyte differentiation and metabolism, but also has an antiproliferative effect in several tissues, including colonic mucosa, where it is highly expressed. Loss-of-function mutations have been reported in about 10% of sporadic primary colon cancer. Acromegalic patients have an increased prevalence of colonic neoplasms and lower PPARgamma levels in the colonic mucosa. Thus, PPARgamma may act as a tumor suppressor gene, and its reduced expression or loss-of-function mutations may contribute to tumorigenesis. In this study the expression and mutations of the PPARgamma gene in the colonic polyps and mucosa outside polyps were investigated in 10 acromegalic and 17 non-acromegalic patients. PPARgamma expression was evaluated by RT-PCR. PPARgamma was expressed in each sample, but expression appeared to be lower in polyps than in mucosa outside polyps from either acromegalic or non-acromegalic patients. All exons of the PPARgamma gene were directly sequenced after PCR amplification: no mutations were found either in acromegalic or in non-acromegalic patients. In conclusion, the results of this preliminary study suggest that the lower expression of PPARgamma rather than somatic mutations of this gene is involved in colonic tumorigenesis.

Measurements of serum thyroxine binding globulin (TBG) by a ligand partitioning sandwich assay were performed in 173 healthy subjects between three months and 92 yr of age. Significant sex-related differences were observed in subjects aged 21 to 50 yr. In males, serum TBG declined progressively reaching a nadir in the fourth decade and then increased with advancing age. In contrast, no significant age-related variation was observed in females.

Amiodarone, an iodine-containing drug used frequently in the treatment of cardiac arrhythmias and angina pectoris, has many effects on thyroid hormone metabolism, including decreasing the production of triiodothyronine (T3) and decreasing the clearance of thyroxine and reverse T3. These effects result in elevated serum thyroxine and reverse T3 concentrations and decreased serum T3 concentrations. In addition, iodine-induced hyperthyroidism or hypothyroidism may occur in patients chronically treated with amiodarone. This study is a retrospective analysis of the incidence of thyroid dysfunction in Lucca and Pisa, West Tuscany, Italy, and in Worcester, Massachusetts. Hyperthyroidism was a more frequent (9.6%) complication of amiodarone therapy in West Tuscany, where iodine intake is moderately low; hypothyroidism was more frequent (22%) in Worcester, where iodine intake is sufficient. In patients receiving chronic amiodarone therapy, clinically suspected hyperthyroidism is best confirmed by showing elevations in serum T3 or free T3 concentrations; hypothyroidism is best diagnosed by showing an elevated serum thyrotrophin concentration. Thyroid function should be carefully monitored in patients receiving amiodarone chronically, especially if they have goiter or Hashimoto's thyroiditis.