Transitional cell carcinoma of urinary bladder with metastasis in lumbar vertebrae and spinal cord compression in an ocelot(Leopardus pardalis)

This paper reports a case of nonpapillary and infiltrative transitional cell carcinoma (TCC) of the urinary bladder with metastasis of lumbar vertebrae and spinal cord compression in an adult female ocelot (Leopardus pardalis), from the Mato Grosso state, Brazil. The ocelot had pelvic limb paralysis and skin ulcers in the posterior region of the body and was submitted to euthanasia procedure. At necropsy was observed a multilobulated and irregular shaped, yellowish to white nodule in the urinary bladder. The nodule had a soft consistency and arised from the mucosa of the urinary bladder extending throughout the muscular layers and the serosa. Nodules of similar appearance infiltrating the vertebral column the at L6 and L7 vertebrae with corresponding spinal canal invasion were also observed. The histological evaluation showed epithelial neoplastic proliferation in the urinary bladder with characteristics of nonpapillary and infiltrative TCC, with positive immunohistochemical staining for pancytokeratin, and strong immunostaining for cytokeratin of low molecular weight, and weak or absent labeling for high molecular weight cytokeratin. This is the first report of TCC of urinary bladder in ocelot in Brazil.

Morphological and immunohistochemical characterization of angiogenic and apoptotic factors and the expression of thyroid receptors in the ovary of tilapia Oreochromis niloticus in captivity

Morphological and immunohistochemical characterization of angiogenic and apoptotic factors and the expression of thyroid receptors in the ovary of tilapia Oreochromis niloticus in captivity were studied. The morphological evaluation of the ovaries was performed by histological paraffin embedded and stained with HE. The immunohistochemical expressions of CDC47, VEGF, Flk-1, angiopoietin, Tie-2 and thyroid receptor (TRα) were performed by the technique of streptavidein-biotin-peroxidase. Apoptosis was assessed using the TUNEL kit. The relative expression of thyroid hormone receptors (TRα and TRβ) was assessed by RT-PCR real time. The nuclear expression of CDC47 increased with the stage of maturation of the oocyte and was observed in the follicle cells. Apoptotic bodies were observed in the follicular cells of atretic follicles and postovulatory follicles from the ovaries of 150g and 350g fish. Expression of VEGF and its receptor Flk-1 was also observed in the follicular cells, and the expression of both increased with the maturity of the oocyte, with a higher intensity observed in the full-grown follicle. The expression of angiopoietin and of its receptor (Tie 2) was discrete and moderate respectively. TRα expression was independent of follicular development. However, the 350 g tilapia exhibited higher expression of TRβ compared with the 50 g tilapia. We conclude that the proliferative activity and the expression of VEGF and its receptor increase with follicular maturation and that the TRs expression increases with ovarian maturity in tilapia (Oreochromis niloticus).

Carcinoma hepatocelular metastático em Jaguatirica (Leopardus pardalis )

RESUMO: O carcinoma hepatocelular (CHC) é uma neoplasia rara nos animais domésticos e em espécies selvagens foi relatado somente em antílopes, veado, cães da pradaria e furões, mas não existem relatos em Leopardus pardalis (jaguatirica). Este trabalho descreve um caso de carcinoma hepatocelular metastático em uma fêmea felina de aproximadamente 18 anos de idade, da espécie Leopardus pardalis, proveniente do Parque Zoobotânico de Teresina-PI, com histórico de anorexia, apatia e evolução ao óbito que foi encaminhada ao Setor de Patologia Animal da Universidade Federal do Piauí para exame anatomopatológico. À necropsia foram observadas duas nodulações de aproximadamente 8,0cm de diâmetro no fígado, de coloração variando da brancacenta ao vermelhado claro, amarelada a vermelho escuro, subdivididas em lóbulos por tecido conjuntivo. No pâncreas foram observadas múltiplas nodulações de aproximadamente 1,0 cm de diâmetro, com superfície lisa, consistência firme, coloração vermelho-amarelada. A superfície de corte dos rins também apresentava várias nodulações milimétricas de distribuição multifocal, na região córtico-medular, consistência firme, coloração branco-acinzentada ou amarelada, sugerindo metástase. Os fragmentos das lesões de fígado foram coletados e no exame microscópico observaram-se proliferação de hepatócitos em cordões bem diferenciados, formando trabéculas com espessura de três ou mais células. Os hepatócitos apresentavam-se volumosos, pleomórficos, com citoplasma eosinofílico. Na coloração com PAS constataram-se, regularmente, acúmulo de glicogênio nos hepatócitos neoplásicos. A confirmação foi feita pela técnica de imunoistoquímica, utilizando-se anticorpo monoclonal (Hepatocyte Specific Antigen). Os achados anatomohistopatológicos, e o auxilio da imunoistoquímica permitiram concluir pelo diagnóstico de hepatocarcinoma trabecular metastático em Leopardus pardalis criado em cativeiro.

Prolactin inhibits auto- and cross-induction of thyroid hormone and estrogen receptor and vitellogenin genes in adult Xenopus (Amphibia) hepatocytes

It is well known that virtually every tissue of the amphibian larvae is highly sensitive to the mutually antagonistic actions of thyroid hormone (TH) and prolactin (PRL), but it is not known if adult amphibian tissues respond similarly to these two hormones. We have previously shown that very low doses of triiodothyronine (T3) rapidly and strongly potentiate the activation of silent vitellogenin (Vit) genes by estrogen (E2) and the autoinduction of estrogen receptor (ER) transcripts in primary cultures of adult Xenopus hepatocytes. This response to T3 is accompanied by the upregulation of thyroid hormone receptor b (TRb) mRNA. Using Northern blot and RNase protection assays, we now show that ovine PRL added for 12 h along with 2 x 10-9 M T3 will completely prevent potentiation of E2 induction of Vit mRNA in primary cultures of adult Xenopus hepatocytes. PRL also abolished the auto-upregulation of TRb mRNA and the cross-activation of autoinduction of ER mRNA. Thus, we show for the first time that the anti-TH action of PRL that is manifested in Xenopus tadpole tissues during metamorphosis is retained in adult liver, and suggest that the mutually antagonistic actions of the two hormones may be brought about by similar molecular mechanisms in larval and adult amphibian tissues

Complications of surgical treatment of cervical carcinoma

A total of 302 patients with stage Ib and IIa cervical carcinoma were submitted to radical hysterectomy and lymphadenectomy during the period from 1980 to 1994. The morbidity rate was 37.5% and the mortality rate 0.6%. The most common intraoperative complications were injuries to the great pelvic vessels and the most frequent postoperative complications involved the urinary tract. The leading causes of morbidity were urinary infection (20.8%), bladder dysfunction (9.2%) and ureteral fistulas (2.9%). Although the rate of complications was high, morbidity has been decreasing over the last five years. Thus, radical hysterectomy continues to be one of the methods for the treatment of early cervical carcinoma that presents an acceptable 5-year survival rate.

Thyroid function in post-weaning rats whose dams were fed a low-protein diet during suckling

This study was designed to evaluate the thyroid and pituitary hormone levels in post-weaning rats whose dams were fed a low-protein diet during suckling (21 days). The dams and pups were divided into 2 groups: a control group fed a diet containing 22% protein that supplies the necessary amount of protein for the rat and is the usual content of protein in most commercial rat chow, and a diet group fed a low-protein (8%) diet in which the protein was substituted by an isocaloric amount of starch. After weaning all dams and pups received the 22% protein diet. Two hours before sacrifice of pups aged 21, 30 and 60 days, a tracer dose (0.6 µCi) of 125I was injected (ip) into each animal. Blood and thyroid glands of pups were collected for the determination of serum T4, T3 and TSH and radioiodine uptake. Low protein diet caused a slight decrease in radioiodine uptake at 21 days, and a significant decrease in T3 levels (128 ± 14 vs 74 ± 9 ng/dl, P<0.05), while T4 levels did not change and TSH was increased slightly. At 30 days, T3 and TSH did not change while there was a significant increase in both T4 levels (4.8 ± 0.3 vs 6.1 ± 0.2 µg/dl, P<0.05) and in radioiodine uptake levels (0.34 ± 0.02 vs 0.50 ± 0.03%/mg thyroid, P<0.05). At 60 days serum T3, T4 and TSH levels were normal, but radioiodine uptake was still significantly increased (0.33 ± 0.02 vs 0.41 ± 0.03%/mg thyroid, P<0.05). Thus, it seems that protein malnutrition of the dams during suckling causes hypothyroidism in the pups at 21 days that has a compensatory mechanism increasing thyroid function after refeeding with a 22% protein diet. The radioiodine uptake still remained altered at 60 days, when all the hormonal serum levels returned to the normal values, suggesting a permanent change in the thyroid function

Pituitary-thyroid axis in short- and long-term experimental diabetes mellitus

Short-term experimental diabetes mellitus (DM) produces a significant decrease in serum thyroid hormones, a decreased or normal serum thyroid-stimulating hormone (TSH) and a reduction in hepatic and renal T4-5'-deiodination. However, little is known about the effects of chronic diabetes mellitus on the pituitary-thyroid axis function. We evaluated the changes induced by very short-term (6 days), short-term (15 days) and chronic (6 months) streptozotocin-induced diabetes mellitus in 3-month old female Dutch-Miranda rat serum T4, serum TSH and T4-5'-deiodinase activity in the thyroid and pituitary glands. Serum hormones were determined by specific radioimmunoassays. Iodothyronine-5'-deiodinase activities were assayed in the thyroid and pituitary microsomal fractions using 2 µM T4 as substrate. Mean serum T4 was significantly decreased from 3.3 to 2.0 µg/dl 6 days after diabetes mellitus induction, and from 2.2 to 1.5 µg/dl after 15 days of DM, with no significant changes in serum TSH, indicating a decreased pituitary TSH responsiveness to the diminished suppression by T4, even though pituitary T4-5'-deiodinase activity was unchanged. Thyroid T4-5'-deiodinase was unchanged after 6 days of diabetes mellitus, but was significantly increased from 20.6 to 37.0 pmol T3/mg protein after 15 days. Six months after diabetes mellitus induction, both serum T4 and thyroid T4-5'-deiodinase returned to normal ranges and serum TSH was unchanged, although pituitary T4-5'-deiodinase was now significantly decreased from 2.7 to 1.7 pmol T3/mg protein. These findings indicate that some kind of adaptation to chronic insulinopenia may occur at the thyroid level, but this does not seem to be true for the pituitary

Effects of estradiol benzoate on 5'-iodothyronine deiodinase activities in female rat anterior pituitary gland, liver and thyroid gland

There is little information on the possible effects of estrogen on the activity of 5'-deiodinase (5'-ID), an enzyme responsible for the generation of T3, the biologically active thyroid hormone. In the present study, anterior pituitary sonicates or hepatic and thyroid microsomes from ovariectomized (OVX) rats treated or not with estradiol benzoate (EB, 0.7 or 14 µg/100 g body weight, sc, for 10 days) were assayed for type I 5'-ID (5'-ID-I) and type II 5'-ID (5'-ID-II, only in pituitary) activities. The 5'-ID activity was evaluated by the release of 125I from deiodinated 125I rT3, using specific assay conditions for type I or type II. Serum TSH and free T3 and free T4 were measured by radioimmunoassay. OVX alone induced a reduction in pituitary 5'-ID-I (control = 723.7 ± 67.9 vs OVX = 413.9 ± 26.9; P<0.05), while the EB-treated OVX group showed activity similar to that of the normal group. Thyroid 5'-ID-I showed the same pattern of changes, but these changes were not statistically significant. Pituitary and hepatic 5'-ID-II did not show major alterations. The treatment with the higher EB dose (14 µg), contrary to the results obtained with the lower dose, had no effect on the reduced pituitary 5'-ID-I of OVX rats. However, it induced an important increment of 5'-ID-I in the thyroid gland (0.8 times higher than that of the normal group: control = 131.9 ± 23.7 vs ovx + EB 14 µg = 248.0 ± 31.2; P<0.05), which is associated with increased serum TSH (0.6-fold vs OVX, P<0.05) but normal serum free T3 and free T4. The data suggest that estrogen is a physiological stimulator of anterior pituitary 5'-ID-I and a potent stimulator of the thyroid enzyme when employed at high doses

Autoradiographic thyroid evaluation in short-term experimental diabetes mellitus

Previous studies have shown that in vitro thyroid peroxidase (TPO) iodide oxidation activity is decreased and thyroid T4-5'-deiodinase activity is increased 15 days after induction of experimental diabetes mellitus (DM). In the present study we used thyroid histoautoradiography, an indirect assay of in vivo TPO activity, to determine the possible parallelism between the in vitro and in vivo changes induced by experimental DM. DM was induced in male Wistar rats (about 250 g body weight) by a single ip streptozotocin injection (45 mg/kg), while control (C) animals received a single injection of the vehicle. Seven and 30 days after diabetes induction, each diabetic and control animal was given ip a tracer dose of 125I (2 µCi), 2.5 h before thyroid excision. The glands were counted, weighed, fixed in Bouin's solution, embedded in paraffin and cut. The sections were stained with HE and exposed to NTB-2 emulsion (Kodak). The autohistograms were developed and the quantitative distribution of silver grains was evaluated with a computerized image analyzer system. Thyroid radioiodine uptake was significantly decreased only after 30 days of DM (C: 0.38 ± 0.05 vs DM: 0.20 ± 0.04%/mg thyroid, P<0.05) while in vivo TPO activity was significantly decreased 7 and 30 days after DM induction (C: 5.3 and 4.5 grains/100 µm2 vs DM: 2.9 and 1.6 grains/100 µm2, respectively, P<0.05 ). These data suggest that insulin deficiency first reduces in vivo TPO activity during short-term experimental diabetes mellitus

Thyroid hormone regulates protein expression in C6 glioma cells

Thyroid hormone (T3) is essential to normal brain development. Previously, we have shown that T3 induces cerebellar astrocyte proliferation. This effect is accompanied by alteration in glial fibrillary acidic protein (GFAP) and fibronectin organization. In the present study, we report that the C6 glioma cell line, which expresses GFAP and is classified as an undifferentiated astrocytic cell type, is a target for T3 action. The C6 monolayers were treated with 50 nM T3 for 3 days, after which the cells were maintained for 2 days without medium changes. In C6 cells, T3 induced the expression of proteins of 107, 73 and 62 kDa. The hormone also up-regulated protein bands of 100 (+50%), 37 (+50%) and 25.5 kDa (+50%) and down-regulated proteins of 94 (-100%), 86.5 (-100%), 68 (-100%), 60 (-100%), 54 (-33%), 51 (-33%) and 43.5 kDa (-33%). We suggest, on the basis of molecular mass, that the 54-, 51- and 43.5-kDa proteins could be the cytoskeletal proteins vimentin, GFAP and actin, respectively. The down-regulation of these proteins may be involved in the effects of thyroid hormone on C6 differentiation.

Analysis of p53 expression and proliferative assessment using PCNA in localized prostate carcinoma

The surgical specimens from 51 men submitted to radical prostatectomy for localized prostate cancer were examined by immunohistochemistry using proliferation cell nuclear antigen (PCNA) monoclonal antibody to evaluate the proliferative index (PI). The relationship between PI, biological variables and p53 protein expression was evaluated by immunohistochemistry. PI was low in invasive localized prostate carcinoma (mean, 12.4%) and the incidence of PCNA-positive cells was significantly higher in tumors with p53 expression (P = 0.0226). There was no statistical difference in PCNA values when biological parameters such as Gleason score, tumor volume, extraprostatic involvement, seminal vesicle infiltration or lymph node metastasis were considered. We conclude that proliferative activity is usually low in prostate carcinoma but is correlated with p53 immune staining, indicating that p53 is important in cell cycle control in this neoplasm.

Reactivity of anti-thyroid antibodies to thyroglobulin tryptic fragments: comparison of autoimmune and non-autoimmune thyroid diseases

Studies concerning the antigenicity of thyroglobulin fragments allow the characterization of the epitopes but do not consider the role of heavier antigenic fragments that could result in vivo from the action of endoproteases. Here we assess the relative importance of the fragments obtained from thyroglobulin by limited proteolysis with trypsin and compare by immunoblotting their reactivity to serum from patients with autoimmune (Graves' disease and Hashimoto's thyroiditis) and non-autoimmune (subacute thyroiditis) disease. The results showed no difference in frequency of recognition of any peptide by sera from patients with autoimmune thyroiditis. In contrast, sera from patients with subacute thyroiditis reacted more frequently with a peptide of 80 kDa. These results suggest the presence of antibody subpopulations directed at fragments produced in vivo by enzymatic cleavage of thyroglobulin. This fragment and antibodies to it may represent markers for subacute thyroiditis.

Thyroid peroxidase activity is inhibited by amino acids

Normal in vitro thyroid peroxidase (TPO) iodide oxidation activity was completely inhibited by a hydrolyzed TPO preparation (0.15 mg/ml) or hydrolyzed bovine serum albumin (BSA, 0.2 mg/ml). A pancreatic hydrolysate of casein (trypticase peptone, 0.1 mg/ml) and some amino acids (cysteine, tryptophan and methionine, 50 µM each) also inhibited the TPO iodide oxidation reaction completely, whereas casamino acids (0.1 mg/ml), and tyrosine, phenylalanine and histidine (50 µM each) inhibited the TPO reaction by 54% or less. A pancreatic digest of gelatin (0.1 mg/ml) or any other amino acid (50 µM) tested did not significantly decrease TPO activity. The amino acids that impair iodide oxidation also inhibit the TPO albumin iodination activity. The inhibitory amino acids contain side chains with either sulfur atoms (cysteine and methionine) or aromatic rings (tyrosine, tryptophan, histidine and phenylalanine). Among the amino acids tested, only cysteine affected the TPO guaiacol oxidation reaction, producing a transient inhibition at 25 or 50 µM. The iodide oxidation inhibitory activity of cysteine, methionine and tryptophan was reversed by increasing iodide concentrations from 12 to 18 mM, while no such effect was observed when the cofactor (H2O2) concentration was increased. The inhibitory substances might interfere with the enzyme activity by competing with its normal substrates for their binding sites, binding to the free substrates or reducing their oxidized form.

Clinical results of the use of mitotane for adrenocortical carcinoma

Mitotane (o,p'-DDD) acts mainly as an inhibitor of intramitochondrial pregnenolone and cortisol synthesis. Its adrenolytic effect depends on metabolic activation due to conversion to o,p'-DDA and o,p'-DDE. The drug has been used for 40 years in the treatment of adrenocortical carcinoma, mainly its regional and metastatic stage, as an adjuvant to surgical resection of the tumor. In the medical literature there are controversial opinions about its efficacy for the treatment of adrenocortical carcinoma. In our experience, mitotane administered immediately after surgery appeared to be much more efficient than when administered later. We have administered this drug in all cases of microscopically confirmed adrenocortical carcinoma, irrespectively of stage at the time of surgery, for fear of a false too optimistic classification. In our series of 82 patients with adrenocortical carcinoma, 59 patients have been treated with mitotane, 32 of them immediately after surgery, and 27 with a delay of 2 to 24 months. Today there are 18 survivors in the group of patients treated with mitotane soon after the operation and only 6 survivors in the group receiving mitotane with a delay. All patients were simultaneously given replacement therapy. Undesired effects of mitotane administration included increased aminotransferase and alkaline phosphatase activity, decreased white cell, platelet or red cell number, and myasthenia. Furthermore, we used mitotane with good results in Cushing's syndrome of non-malignant origin as pre-treatment before surgery or in long-term treatment for patients with poor tolerance of other adrenal inhibitors.

Estradiol decreases iodide uptake by rat thyroid follicular FRTL-5 cells

Estradiol has well-known indirect effects on the thyroid. A direct effect of estradiol on thyroid follicular cells, increasing cell growth and reducing the expression of the sodium-iodide symporter gene, has been recently reported. The aim of the present investigation was to study the effect of estradiol on iodide uptake by thyroid follicular cells, using FRTL-5 cells as a model. Estradiol decreased basal iodide uptake by FRTL-5 cells from control levels of 2.490 ± 0.370 to 2.085 ± 0.364 pmol I-/µg DNA at 1 ng/ml (P<0.02), to 1.970 ± 0.302 pmol I-/µg DNA at 10 ng/ml (P<0.003), and to 2.038 ± 0.389 pmol I-/µg DNA at 100 ng/ml (P<0.02). In addition, 4 ng/ml estradiol decreased iodide uptake induced by 0.02 mIU/ml thyrotropin from 8.678 ± 0.408 to 7.312 ± 0.506 pmol I-/µg DNA (P<0.02). A decrease in iodide uptake by thyroid cells caused by estradiol has not been described previously and may have a role in goiter pathogenesis.