Morphohistological aspects of tumors and tumor-like changes in the thyroid gland

The results of the thyroid gland (TG) state investigation in 1027 patients, ageing from 14 to 75 years, operated on in 1986-1995 yrs., are adduced. In 60.5% of patients the diffuse-nodular goitre was diagnosed, in 9.5%--Hashimoto's thyroiditis, in 9.5%--TG cancer, in 2.8%--other pathology. To establish the interrelationship of pre-cancer changes and a TG cancer it is necessary to point out the concomitant morphologic change beside the main diagnosis, which determines the clinical tactics.     

Gender-specific changes in thyroid hormone-glucuronidating enzymes in rat liver during short-term fasting and long-term food restriction

Glucuronidation is a major pathway of thyroid hormone metabolism in rats, involving at least three different hepatic UDP-glucuronyltransferases (UGTs): bilirubin UGT, phenol UGT and androsterone UGT. We have studied the effects of short-term (3 days) fasting and long-term (3 weeks) food restriction to one-third of normal intake (FR33) on hepatic UGT activities for thyroxine (T4), triiodothyronine (T3), bilirubin and androsterone in male and female Wistar rats with either a functional (high activity, HA) or a defective (low activity, LA) androsterone UGT gene. Because food deprivation is known to induce centrally mediated hypothyroidism in rats, results were compared with those obtained in methimazole (MMI)-induced hypothyroid rats. Both fasting and FR33 produced largely parallel increases in T4 and bilirubin UGT activities. These effects were greater in males than in females, and were reproduced in MMI-treated rats. In male and female HA rats, fasting induced insignificant increases in T3 UGT activity and had no effect on androsterone UGT activity. In male HA rats, FR33 was associated with an increase in T3 UGT activity, while androsterone UGT activity showed little change. However, in female HA rats both T3 and androsterone UGT activities were markedly decreased by FR33. Triiodothyronine UGT activity in LA rats was strongly decreased compared with HA rats, but was not further decreased by FR33 in female LA rats, supporting the importance of androsterone UGT for T3 glucuronidation. These results demonstrate different sex-dependent effects of food deprivation on hepatic T4 and T3 glucuronidation that are associated with changes in the expression of bilirubin UGT and androsterone UGT, respectively. For the increased T4 and bilirubin UGT activities at least, these effects appear to be mediated by the hypothyroid state of the (semi)starved animals.     

The use of diets incorporating soy products in the treatment of experimental alimentary dystrophy

The more accurate definition of the role of cerebral mechanism in migraine development by means of contingent negative deviation (CND) method was the aim of this investigation. The significant alterations of some parameters were revealed in patients with migraine between the fits as compared with controls. The same indices were normal during the very fits. The CND indices were similar in patients with chronic Headache of strain and healthy individuals. The clinical neurophysiological analysis didn't reveal any significant dependence of CND changes clinical peculiarities and anxious and depressive disorders. The significant elevation of CND parameters observed between the attacks suggests presence of superfluous activity in cerebral structures (noradrenergic mainly) in patients with migraine without aura. Such alterations in their action lead, apparently, to headache attack development.     

Effects of 6-N-propyl-2-thiouracil on growth, hormonal profiles, carcass and reproductive traits of boars

Neonatal 6-N-propyl-2-thiouracil (PTU)-induced hypothyroidism reduces body weight but increases testicular size in adult male rodents. The objective of this study was to determine the effect of prepubertal PTU treatment on boars. For Experiment I, boars (n = 28) were randomly allotted to eight pens. Each pen received one of four PTU doses (0, 0.01, 0.03 and 0.1% in a basal diet) between 28 and 56 days of age (DOA). Due to a lack of difference among three PTU treatments, PTU-treated boars were pooled. Boars treated with PTU had lower (P < 0.05) ADG during treatment, lighter (P < 0.05) BW after 56 DOA and less (P < 0.05) developed epididymides at 154 DOA. For Experiment II, boars (n = 19) were randomly allotted to six pens. Each pen received one of three PTU treatments orally as: control (carrier), PTU-I (0.002% BW of PTU daily between 7 and 70 DOA), or PTU-II (0.002% BW of PTU daily between 28 and 91 DOA). During treatment, PTU-treated boars had lower (P < 0.05) serum T4 levels, rectal temperature, feed intake and ADG. Boars treated with PTU had lower (P < 0.05) BW between 63 and 154 DOA but higher (P < 0.05) gain/feed between 105 and 133 DOA. Boars treated with PTU had less (P < 0.05) developed epididymides and sperm count per gram testis at 238 DOA. These results suggest that prepubertal PTU-induced hypothyroidism had significant effects on growth, hormonal profiles, and reproductive traits of boars; however, it does not appear to be an effective method for increasing testis size and sperm production of commercial boars.     

Value of color-coded Doppler sonography in the differential diagnosis of nodular thyroid gland changes

AIM: The incidence of functional autonomous adenomas, detected in every second nodular goiter by scintigraphic methods is very high in an area of iodine deficiency. The color-coded Doppler sonography (CCDS) as a diagnostic tool in differentiating thyroid nodules is discussed controversially. METHODS: In this prospective study we investigated the value of CCDS in 200 patients with nodular thyroid alterations compared with 99m-Technetium (Tc) scintigraphy. RESULTS: Focal maximas of Tc-uptake were detected in 22.5% of all patients, and 44.5% of the thyroid nodules showed increased vascularity. There was no correlation between nodular vascularity and thyroid 99m-Tc uptake (TcTU). In contrast to this we could demonstrate a significant relation between vascularity and the diameter of the nodule (p < 0.0001). The results are discussed in the context of method specific limitations of ultrasound examinations. CONCLUSION: Our results confirm that CCDS has no great importance in the differentiation of thyroid nodules. Scintigraphy remains the diagnostic method of choice to assess the topographic thyroid function.     

Anaplastic cancer, lymphoma, and metastases of the thyroid gland

Not all thyroid carcinomas behave in an indolent fashion. There is a rare group of thyroid neoplasms that is biologically aggressive and carries a poor prognosis. These tumors include poorly differentiated tumors, anaplastic, and thyroid lymphomas. Poorly differentiated tumors are important tumors to recognize because aggressive surgical intervention appears to offer the best chance for long-term survival. Until recently, anaplastic carcinoma was universally fatal. Preoperative chemotherapy and hyperfractionated radiation has led to better local control and a few long-term survivors. The role of the surgeon in the treatment of the thyroid lymphomas remains controversial, however, most would agree that the surgeons role is limited, because these tumors are radiosensitive and chemosensitive.     

Indications for percutaneous radiotherapy in carcinoma of the thyroid gland. Freiburg consensus

At the University of Freiburg, a consensus was arrived at concerning the place of external radiotherapy in the management of thyroid cancer. External irradiation is always indicated in papillary and folliculary carcinoma in the pT4 stage of pTNM classification but not in those in pT1-3 pN0 stage. In the presence of lymph-node metastases and distant metastases, an individual treatment concept is recommended, which should be set up in an interdisciplinary conference regarding all risk factors, especially the age and sex of the patient, the histology and grading of the tumor and the completeness of tumor resection. Finally, radiotherapy is usually not indicated in medullary thyroid carcinoma, whereas it is always indicated in anaplastic carcinoma.     

Ultrasonic examination of the thyroid gland. Possibilities and limitations

In 440 patients with various thyroid disorders scintiphotography and ultrasonography were carried out. For ultrasonic examination both the A-mode and B-mode display technics were employed, included in the study were 324 patients with hypofunctioning solitary nodules; a histopathologic diagnosis could be obtained in 151 of these. The method proved to be especially valuable for differentiating between solid and cystic nodules. This is of practical importance because completely cystic nodules are nearly always benign and may be treated by thin needle puncture with aspiration of the cyst fluid. In addition, ultrasonography is of some value in making a better functional classification of nodules, better estimating the size of the thyroid and in the follow-up of patients with various thyroid disorders who are under treatment or untreated. Differentiating between benign and malignant solid nodules was not possible with the technic used. The examination can be safely carried out in pregnancy. The limitations of the technic are discussed.     

Morphometric changes in the prepubertal female rat thyroid gland following acute exposure to 2,2'',4,4''-tetrachlorobiphenyl and Aroclor 1242

Rabbit polyclonal antibodies were raised against the C-terminal fragment (amino acid residues 318-451) of human gamma-tubulin. These antibodies were used to stain cultured cells of various tissues (epithelium, nervous tissue, fibroblasts) from different animals (human, monkey, pig, rat, kangaroo rat, mouse, hamster, chicken, triton). The antibodies specifically stained centrioles in the interphase and mitotic cells of mammals, but not birds (chicken) or amphibians (newt). In the interphase cells, centrioles were stained as a pair of dots (or as a double dot) in 96-97% of the cells. The distances between the maternal and filial centrioles varied in different cultures. Procentrioles were stained in certain cells, but with less intensity than mature centrioles. In mitotic cells, the antibodies revealed two spots corresponding to two mitotic poles. The spots in mitosis were significantly larger than the interphase dots, but the staining was more faint. In spontaneous tripolar mitoses, only two poles were stained. Thus, it was shown that, on the one hand, gamma-tubulin is associated with centrioles irrespective of whether or not they serve as the microtubule organizing centres and, on the other hand, gamma-tubulin might not be an essential component of the microtubule organizing centres.     

First results of radioiodine therapy of multifocal and disseminated thyroid gland autonomy and use of a TcTUs-adapted dose concept

AIM: The presented study examines prospectively the efficiency of a dose concept for radioiodine therapy (RIT) adapted to the pretherapeutic 99mTc-pertechnetate thyroid uptake under suppression (TcTUs) in patients with multifocal (MFA) and disseminated (DISA) autonomy. This concept considers the total thyroid as target volume and uses target doses from 150 Gy to 300 Gy according to the TcTUs, which is as a measure for the "autonomous volume" of the thyroid. METHODS: The data of 75 patients (54 female, 21 male; age 71 +/- 9 years) with MFA of DISA were evaluated. RIT was performed on patients presenting with normal values for free triiodothyronine and thyroxine and endogenous suppression of the basal thyrotropin (TSH). The following target dose were used for a TcTUs of 1.5-2.5% 150 Gy, for 2.51-3.5% 200 Gy, for 3.51-4.5% 250 Gy, and for > 4.5% 300 Gy. The radiation dose to be administered was calculated using a modified Marinelli formula. The therapy was considered as successful. When the basal TSH was above 0.5 mU/l and autonomous areas had disappeared in thyroid scintigraphy or the TcTU was below 1.5%, respectively. The average follow-up period was 8 +/- 4 months. RESULTS: The success rates average to 92%. Only in one case a subsequent subclinical hypothyroidism and in a further case an immunogenic hyperthyroidism occurred. CONCLUSION: The presented data indicate that even patients with a marked autonomy (TcTUs > 3.5%) can thus expected to be cured by of a one time therapy with success rate of over 90% using the presented dose concept. The rate of early hypothyroidism can altogether be estimated as very low.     

Guidelines for the use of radio-iodine, thyroid hormone, and treatment of metastatic disease in patients with differentiated thyroid cancer

The treatment of metastatic differentiated thyroid carcinoma is currently at a crossroad. The stunning effect of imaging doses of RAI on subsequent treatment doses is being recognized. Alternatives to RAI imaging for diagnostic purposes are being tested; these include ultrasonography for local and cervical nodal remnants/recurrences, Sestamibi and other isotope scanning that do not require the discontinuation of TSH suppression, and the measurement of circulating thyroglobulin that is rapidly becoming the cornerstone of the detection and the treatment follow-up of metastatic carcinoma.     

Removal of the caudae epididymides to create infertile boars for use in estrus detection programs

Epididymectomies (removal of the caudae epididymides) were performed to create infertile boars. The simplicity of this procedure allowed for it to be easily performed on physically or chemically restrained boars that weighted 30 kg. Benefits of the use of epididymectomy, rather than vasectomy, to render boars infertile include low cost, simplicity, reduced surgical time, and minimum need of surgical instruments and materials. Epididymectomized boars are used in swine breeding management programs.     

Malignant hemangioendothelioma of the thyroid gland: new results on pathogenesis, therapy and prognosis

BACKGROUND: Malignant hemangioendothelioma of the thyroid is a rare tumor predominantly described in areas with endemic goiter like the Alpine regions. The estimated incidence of the disease is between 0.15 and 0.25 per 100,000 inhabitants per year for Western Austria. The prognosis is reported to be dismal. MATERIALS AND METHODS: Between 1982 and 1995, 10 cases with immunohistochemically confirmed malignant hemangioendotheliomas of the thyroid were referred to our department for postoperative or palliative treatment. Two patients with clear margins at surgery received no adjuvant radiotherapy and were only observed. By surgery, clear margins (R-0 resection) were achieved in 5, microscopic residuals (R-1) were left in 3, and gross residual disease in 1 patient. One patient had an inoperable primary tumor. Postoperative radiotherapy was administered in 6 cases, 4 of them additionally received the radiosensitizer razoxane. Total tumor doses ranged between 58 and 65 Gy. RESULTS: Local tumor control was achieved in 9 of 10 patients; 4 of 10 lived longer than 4 years. The median survival time has not yet been reached and is presently between 7.5 and 21+ months.--Noteworthy is a complete regression of 2 lung metastases in a 72-year-old man by a combination of vindesine, razoxane and radiotherapy. The patient is still in complete remission under a maintenance therapy with vindesine and razoxane since 14 months.--It may also be of interest that 4 of the 10 patients were strongly exposed to vinyl chloride and other polymeric materials during their occupational life. CONCLUSIONS: This small series may indicate that the outcome of this disease may not be uniformly deleterious, and that the resistance to radiotherapy reported in the literature may be questioned.--The data offer new evidence of the occurrence of vinyl chloride-induced angiosarcomas outside the liver, and support observations which have already been published in case reports.     

Production and reproductive responses to use of DairyMAN: a management information system for New Zealand dairy herds

To assess the benefits of on-farm use of a computerized management information system (DairyMAN, Department of Veterinary Clinical Science, Massey University, Palmerston North, New Zealand) on seasonally calving herds of New Zealand, data for 144 herds using this system were compared with a stratified random sample of 294 herds using only the centralized National Dairy Database system during the season 1993 to 1994. Demographic, reproductive performance, and milk yield indices were compared. Herds using DairyMAN had superior reproductive outcomes, measured as a higher percentage (+8.4%) of cows calving during the desired seasonal period (critical in this seasonal system) and a higher percentage of cows (+9.7%) mated at the optimal time to achieve a concentrated calving in the following year. Multiple analysis of covariance was used to differentiate effects. The superior performance was not associated with differences in some of the more commonly used reproductive indices (efficiency of estrus detection, first service nonreturn rate, and pregnancy rate), but the data used in the study do not accurately reflect true performance. Herds using DairyMAN had more information on breeding performance because pregnancy data were available and natural breedings were recorded for a longer period. With cows of equivalent genetic merit, herds using DairyMAN produced more milk (+1.2 L/d per cow) indicating that users achieved better management of the herd through improved attention to managerial details. This improved production was associated with the adoption of DairyMAN but is not shown by this study to be a direct consequence of it. DairyMAN user herds were larger (245 cows) than were herds not using the system (181 cows), but this difference did not significantly affect the various outcomes measured.