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1.
Reprod Domest Anim ; 53(2): 333-343, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29134714

RESUMO

Mammalian uterus contains a population of mesenchymal stem/progenitor cells that likely contribute to endometrial regeneration during each reproductive cycle. In human and mouse, they reside in perivascular, epithelial and stromal compartments of the endometrial functionalis and basalis. Here, we aimed to identify tissue resident cells expressing mesenchymal stem cell markers CD29, CD44, CD90, CD105, CD140b and CD146 in the porcine endometrium. We used single immunofluorescence and Western blotting. Each of these markers was detected in small cells surrounding endometrial blood vessels. CD105 and CD146 were also expressed in single stromal cells. A few stromal and perivascular cells showed the presence of pluripotency marker Oct4 in the cytoplasm, but not in the nucleus, which may imply they are not truly pluripotent. Endometrial cell cultures were examined for the expression of CD29, CD44, CD90, CD105 and CD140b proteins and tested in wound-healing assay and culture model of chemotaxis. In conclusion, our results demonstrate perivascular location of prospective mesenchymal stem/progenitor cells in the porcine endometrium and may suggest that stromal CD105+ and CD146+ cells represent more mature precursors originating from their perivascular ancestors.


Assuntos
Endométrio/citologia , Células-Tronco Mesenquimais/metabolismo , Pericitos/metabolismo , Animais , Biomarcadores/metabolismo , Células Cultivadas , Endométrio/metabolismo , Feminino , Células-Tronco Mesenquimais/citologia , Fator 3 de Transcrição de Octâmero/metabolismo , Pericitos/citologia , Células-Tronco/metabolismo , Sus scrofa
2.
Curr Oncol ; 24(5): e423-e428, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29089812

RESUMO

Tuberous sclerosis complex (tsc), a phacomatosis, is a rare genetic disease (autosomal dominant; incidence: 1 in 6,800-17,300) associated with mutations in the TSC1 and TSC2 genes, 70% of which are sporadic. The disease causes benign tumours in the brain, kidneys, heart, lungs, skin, and eyes; thyroid lesions are extremely rare. A 13-year-old euthyroid boy with a hereditary form of tsc (del 4730G in TSC2, also seen in 2 sisters and the father) was admitted to hospital with a thyroid nodule. Physical examination revealed a nodular left lobe with increased consistency. Thyroid ultrasonography revealed a heterogeneous left lobe, predominantly hypoechoic with multiple microcalcifications and the presence of suspicious cervical lymph nodes on the left side. A macrocalcification was observed on the right lobe. Fine-needle biopsy results showed a few groups of cells with discrete atypical characteristics, including abundant cytoplasm, nuclei with conspicuous nucleoli, intra-nuclear inclusions, and nuclear grooves. The patient underwent total thyroidectomy with lymphadenectomy. Histopathology examination confirmed papillary thyroid carcinoma. The coincidence of endocrine neoplasia including thyroid cancer and tsc is rare, and tsc with papillary thyroid carcinoma has never been described in a child. Studies of mutations in the tumour suppressor genes TSC1, TSC2, and STK11, activating the mtor (mammalian target of rapamycin) pathway, might support their role in the pathogenesis of thyroid cancer.

3.
J Clin Endocrinol Metab ; 99(5): 1648-55, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24517152

RESUMO

CONTEXT AND OBJECTIVE: The incidence of TSH receptor (TSHR) stimulating autoantibodies (TSAbs) in pediatric Graves' disease (GD) is controversial. This large, multicenter study evaluated the clinical relevance of TSAbs in children with GD both with Graves' orbitopathy (GO) and without orbital disease. DESIGN: We conducted a cross-sectional retrospective study. SETTING: Sera were collected in seven American and European academic referral centers and evaluated in a central laboratory. PATIENTS AND SAMPLES: A total of 422 serum samples from 157 children with GD, 101 control individuals with other thyroid and nonthyroid autoimmune diseases, and 50 healthy children were studied. MAIN OUTCOME MEASURES: TSAbs were measured using a novel, chimeric TSHR bioassay and a cAMP response element-dependent luciferase. TSH binding-inhibitory Ig (TBII) and parameters of thyroid function were also determined. RESULTS: In 82 untreated children with GD, sensitivity, specificity, and positive and negative predictive values for TSAb and TBII were: 100 and 92.68% (P = .031), 100 and 100%, 100 and 100%, and 100 and 96.15%, respectively. TSAb and TBII were present in 147 (94%) and 138 (87.9%) of the 157 children with GD (P < .039), respectively; and in 247 (94%) and 233 (89%) of the 263 samples from this group (P < .0075), respectively. In children with GD and GO, TSAb and TBII were noted in 100 and 96% (P < .001), respectively. Hyperthyroid children with GD and GO showed markedly higher TSAb levels compared to those with thyroidal GD only (P < .0001). No significant differences were noted for TBII between the two groups. After a 3-year (median) medical treatment, the decrease of TSAb levels was 69% in GD vs 20% in GD and GO (P < .001). All 31 samples of euthyroid children with GO were TSAb positive; in contrast, only 24 were TBII positive (P = .016). All children with Hashimoto's thyroiditis, nonautoimmune hyperthyroidism, type 1 diabetes, and juvenile arthritis and the healthy controls were TSAb and TBII negative. CONCLUSIONS: Serum TSAb level is a sensitive, specific, and reproducible biomarker for pediatric GD and correlates well with disease severity and extrathyroidal manifestations.


Assuntos
Doença de Graves/imunologia , Imunoglobulinas Estimuladoras da Glândula Tireoide/imunologia , Adolescente , Doenças Autoimunes/sangue , Doenças Autoimunes/imunologia , Criança , Feminino , Doença de Graves/sangue , Humanos , Imunoglobulinas Estimuladoras da Glândula Tireoide/sangue , Masculino , Estudos Retrospectivos , Sensibilidade e Especificidade , Hormônios Tireóideos/sangue , Adulto Jovem
4.
Eur Thyroid J ; 1(3): 142-7, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24783013

RESUMO

All cases of familial thyrotoxicosis with absence of evidence of autoimmunity and all children with persistent isolated neonatal hyperthyroidism should be evaluated for familial non-autoimmune autosomal dominant hyperthyroidism (FNAH) or persistent sporadic non-autoimmune hyperthyroidism (PSNAH). First, all index patients should be analysed for the presence/absence of a thyroid-stimulating hormone (TSH) receptor (TSHR) germline mutation, and if they display a TSHR germline mutation, all other family members including asymptomatic and euthyroid family members should also be analysed. A functional characterization of all new TSHR mutations is necessary. Appropriate ablative therapy is recommended to avoid relapses of hyperthyroidism and its consequences, especially in children. Therefore, in children the diagnosis of FNAH or PSNAH needs to be established as early as possible in the presence of the clinical hallmarks of the disease.

5.
J Clin Endocrinol Metab ; 95(5): 2443-50, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20233785

RESUMO

CONTEXT: In 21-hydroxylase (CYP21A2) deficiency (21OHD), the level of in vitro enzymatic function allows for classification of mutation groups (null, A, B, C) and prediction of disease severity. However, genital virilization in affected females correlates only weakly with CYP21A2 mutation groups, suggesting the influence of genetic modifiers. OBJECTIVE: The objective of the study was to investigate the influence of the polymorphic CAG and GGn repeats of the androgen receptor (AR) gene on the degree of genital virilization in 21OHD females. DESIGN AND PATIENTS: Design of the study was the determination of CYP21A2 genotype, degree of genital virilization (Prader stage), and X-weighted biallelic mean of AR CAG and GGn repeat length in 205 females with 21OHD. OUTCOME MEASUREMENTS: Correlation of AR CAG and GGn repeat lengths with Prader stages using nested stepwise logistic regression analysis was measured. RESULTS: CYP21A2 mutation groups null and A showed significantly higher levels of genital virilization than groups B and C (P < 0.01). However, Prader stages varied considerably within mutation groups: null, Prader I-V (median IV); A, Prader I-V (median IV); B, Prader I-V (median III); C, 0-III (median I). Mean GGn repeat length of patients was not significantly associated with Prader stages, classified as low (0-I), intermediate (II-III), or severe (IV-V) (odds ratio per repeat: 0.98, 95% confidence interval 0.71-1.35). In contrast, patients with Prader 0-I showed a trend toward longer CAG repeats without reaching statistical significance (P = 0.07, odds ratio per repeat: 0.82, 95% confidence interval 0.65-1.02). CONCLUSION: Neither CAG nor GGn repeat lengths are statistically significant modifiers of genital virilization in females with 21OHD.


Assuntos
Hiperplasia Suprarrenal Congênita/genética , Receptores Androgênicos/genética , Esteroide 21-Hidroxilase/genética , Repetições de Trinucleotídeos/genética , Virilismo/genética , Hiperplasia Suprarrenal Congênita/classificação , Hiperplasia Suprarrenal Congênita/patologia , Alelos , Primers do DNA , Feminino , Amplificação de Genes , Genótipo , Humanos , Reação em Cadeia da Polimerase , Deleção de Sequência , Virilismo/classificação , Virilismo/patologia
6.
Exp Clin Endocrinol Diabetes ; 118(3): 180-3, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20198557

RESUMO

Treatment of congenital adrenal hyperplasia (CAH) in its salt-wasting form with appropriate doses of glucocorticoids and mineralocorticoids should promote growth, puberty and final height in a similar to normal pattern. However, the individual requirements for these drugs to normalize the hormonal profile and to achieve a physiologic growth pattern may differ. Moreover, the time of onset of puberty is also unpredictable since the course of the disease may predispose for precocity. The aim of this study was to explain the unexpected arrest of growth during puberty in a boy with late-onset CAH, who had been treated with glucocorticoid from early childhood. A short course of GnRH agonist treatment was also introduced in later years. The growth chart reflects two periods of impaired growth velocity preceded by weight loss. The reason for the first decline is difficult to prove retrospectively, but during the second episode the boy became both clinically and hormonally hypogonadal. At that time the anorexia nervosa (AN) was diagnosed according to APA DSM-IV criteria. We conclude that there were several reasons for the discontinued growth spurt and reduced final height in this boy with CAH: (a) early variant of puberty and subsequent late treatment with GnRH agonist, (b) AN possibly occurring during mid-childhood and clearly during puberty and (c) the repeated use of high doses of glucocorticoids. AN, a relatively rare disorder in boys, appears to have had a significant negative effect on this patient's growth and should be considered in the differential diagnosis in CAH children with impaired growth.


Assuntos
Hiperplasia Suprarrenal Congênita/tratamento farmacológico , Anorexia Nervosa/complicações , Glucocorticoides/uso terapêutico , Hormônio Liberador de Gonadotropina/agonistas , Transtornos do Crescimento/etiologia , Adolescente , Hiperplasia Suprarrenal Congênita/complicações , Criança , Pré-Escolar , Glucocorticoides/efeitos adversos , Transtornos do Crescimento/diagnóstico , Humanos , Masculino , Puberdade , Esteroide 21-Hidroxilase/metabolismo
7.
Horm Res ; 70(3): 155-64, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18663316

RESUMO

The Bcl-2 family proteins that control homeostasis of cells play an important role in apoptosis. This group consists of antiapoptotic (Bcl-2, Bcl-XL) and proapoptotic (Bcl-2 associated protein X, Bax; B-cell homologous antagonist/killer, Bak) molecules. In the thyroid, abnormal apoptotic activity may be involved in a variety of diseases such as autoimmune thyroid diseases. The aim of the current study was to estimate the expression of pro- and antiapoptotic proteins in thyroid tissues from young patients with Graves' disease (GD), nontoxic nodular goiter and toxic nodular goiter using Western Blot and immunohistochemistry. Identification of the antiapoptotic Bcl-2 and Bcl-XL molecules in the thyrocytes revealed higher expression of both proteins in patients with GD (assessed as +++/++ and ++/+, respectively). In adolescents with toxic and nontoxic nodular goiter, this expression was lower (Bcl-2 ++/+ , ++/+; Bcl-XL +, +). The tissue material was additionally subjected to Western Blot analysis, which in GD patients showed the presence of Bcl-2 and Bcl-XL in one band p26 kDa. In patients with toxic and nontoxic nodular goiter, the intensity of expression for these two antiapoptotic proteins was lower (referred to band 26 kDa for Bcl-2 and Bcl-XL). Identification of the proapoptotic proteins Bax and Bak revealed their predominance in thyrocytes of GD patients (+, ++/+, respectively) as compared to patients with toxic and nontoxic nodular goiter (0/+, 0/+ for Bax and 0/+, 0/+ for Bak). In GD patients, Western Blot analysis showed Bax expression in one band 21 kDa and Bak in two bands p50, p24 kDa. In patients with nodular goiter, the degree of expression of both proapoptotic proteins was lower and referred to band 21 kDa for Bax (toxic and nontoxic goiter) and 24 kDa for Bak (toxic goiter only). Patients with GD showed a statistically significant correlation between Bcl-2 expression and antibodies against receptor for thyroid stimulating hormone (R = 0.47, p < 0.03); however, such a correlation was not observed in patients with nodular goiter. In conclusion, our findings suggest that the changes in the expression of regulatory proteins of the Bcl-2 family in the thyroid follicular cells indicate the involvement of apoptosis in the pathogenesis of GD.


Assuntos
Bócio Nodular/metabolismo , Doença de Graves/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Adolescente , Adulto , Antitireóideos/uso terapêutico , Apoptose/fisiologia , Western Blotting , Criança , Feminino , Bócio Nodular/sangue , Bócio Nodular/tratamento farmacológico , Bócio Nodular/patologia , Doença de Graves/sangue , Doença de Graves/tratamento farmacológico , Doença de Graves/patologia , Humanos , Imuno-Histoquímica , Masculino , Metimazol/uso terapêutico , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
9.
Endocr Relat Cancer ; 13(2): 427-53, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16728572

RESUMO

According to the literature thyroid nodules are quite rare in the first two decades of life. However, there are some exceptions, relating to areas with an iodine deficiency or affected by radioactive fallout, where the risk of nodules and carcinomas is increased. Therefore, it is a great challenge for the physician to distinguish between benign and malignant lesions preoperatively, and not only in these areas of greater risk. A careful work-up, comprising the patient's history, clinical examination, laboratory tests, thyroid ultrasound, scintigraphy, fine-needle aspiration biopsy (FNAB) and molecular studies, is mandatory to improve the preoperative diagnosis. The differential diagnosis should also include benign thyroid conditions such as: (i) congenital hypothyroidism due to dyshormonogenesis or ectopy, (ii) thyroid hemiagenesis, (iii) thyroglossal duct cyst, (iv) simple goiter, (v) cystic lesion, (vi) nodular hyperplasia, (vii) follicular adenoma, (viii) Graves' disease and (ix) Hashimoto thyroiditis, all of which can predispose to the development of thyroid nodules. The majority of thyroid carcinomas derive from the follicular cell (papillary, follicular, insular and undifferentiated (or anaplastic) thyroid carcinoma), whereas medullary thyroid carcinoma derives from calcitonin-producing cells. Inherited forms of thyroid cancer may occur, especially in relation to medullary thyroid carcinoma. FNAB is a critical factor in establishing the preoperative diagnosis. However, we should keep in mind the fact that a conventional cytological evaluation can miss the neoplastic nature of a lesion and the employment of immunocytochemical and molecular studies of aspirates from FNAB can give us a more precise diagnosis of neoplasia in thyroid nodules once they are detected.


Assuntos
Nódulo da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/patologia , Biópsia por Agulha Fina , Criança , Humanos , Cintilografia , Doenças da Glândula Tireoide/diagnóstico , Doenças da Glândula Tireoide/terapia , Nódulo da Glândula Tireoide/terapia , Ultrassonografia
10.
J Pediatr Endocrinol Metab ; 15(6): 823-30, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12099393

RESUMO

In an iodine deficient area, a high incidence of hot thyroid nodules was observed in children after the introduction of iodine supplementation in 1997. Thirty-one children (28 girls, 3 boys) were identified with hot nodules between the years 1996-2000 (3 patients in 1996, 4 in 1997, 10 in 1998, 7 in 1999, and 7 in 2000). The incidence ratio of hot nodules in this study population increased significantly from 0.23 in 1996 to 0.80 in 1998. In 17 children, radionuclide uptake was confined exclusively to areas corresponding to the nodules. Cancer was detected in one child in post-operative histological examination. In the other 14 children, the predominant uptake was in nodules, but it was also registered within extranodular tissue. In the latter group, eight tumors were eventually diagnosed as cancer and six as benign tumors. The majority of tumors in the entire group was located in the right lobe (19/31) and was accompanied by reduced TSH levels (23/31), but only 14 of the 31 patients had signs of hyperthyroidism. The years 1996-2000, in which the increase in the incidence of "hot" nodules in children with nodular goiter was observed, correspond to a period of enforced salt iodinization. The existence of cancer within hot nodules is rare, ranging from 2-5% of all nodules. By contrast, the risk of cancer in hot nodules in the cohort of this study was significantly higher (9/31; 29.0%), especially in cases of hot nodules with a rudimentary radionuclide uptake in the extranodular area. We conclude that, in geographical regions affected with iodine deficiency, the therapeutic protocol for children with hot nodules should be based primarily on surgery rather than on radioiodine.


Assuntos
Iodo/deficiência , Nódulo da Glândula Tireoide/epidemiologia , Adolescente , Biópsia por Agulha , Criança , Estudos de Coortes , Dieta , Feminino , Humanos , Iodo/uso terapêutico , Masculino , Polônia/epidemiologia , Cintilografia , Fatores de Risco , Neoplasias da Glândula Tireoide/diagnóstico por imagem , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/diagnóstico por imagem , Nódulo da Glândula Tireoide/cirurgia , Tireoidectomia , Resultado do Tratamento
11.
J Pediatr Endocrinol Metab ; 14(7): 901-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11515732

RESUMO

Autoimmune thyroiditis, the most frequent cause of acquired hypothyroidism in childhood and adolescents, is characterized by raised levels of the specific antibodies to thyroperoxidase (TPOAb) and thyroglobulin (TgAb). We report a girl aged 10 years and 9 months who presented with arrested growth and breast development (thelarche). She also exhibited myxedema of the face and legs, prominent striae on the thighs, dry, cold skin, and hypertrichosis on her back. There was no goiter, no history of thyroid pain and no family history of thyroid disease. She complained occasionally of a transient headache. The patient's height was below the 3rd percentile, while her body weight was at the 50th percentile and bone age was normal. Laboratory tests proved severe hypothyroidism (fT4 0 ng/dl, fT3 0.99 pg/ml, TSH >100 microIU/ml plus an increased titer of TPOAb). Thyroid ultrasound supported the diagnosis of thyroiditis. Pituitary PRL and FSH levels and peripheral estradiol were all elevated. L-Thyroxine therapy, instituted following diagnosis, improved the growth velocity to 11 cm/year and the FSH and E2 levels were normalized to prepubertal values. Complete regression of the breast development was observed within 4 months. However, 4 months later a true (central), isosexual LHRH-dependent puberty started. The pubertal features at the time of the original diagnosis might be explained by: 1. the direct action of elevated TRH on gonadotropes to stimulate gonadotropin secretion and on lactotrophes to stimulate PRL secretion, and 2. TSH action on LH and mostly FSH receptors (homologous to TSH receptors) in the ovary, stimulating the secretion of estradiol.


Assuntos
Estatura/fisiologia , Hipotireoidismo/etiologia , Puberdade Precoce/etiologia , Maturidade Sexual/fisiologia , Tireoidite Autoimune/complicações , Criança , Feminino , Transtornos do Crescimento/etiologia , Terapia de Reposição Hormonal , Hormônios/sangue , Humanos , Hipotireoidismo/diagnóstico por imagem , Iodeto Peroxidase/imunologia , Tireoglobulina/imunologia , Tireoidite Autoimune/diagnóstico por imagem , Tiroxina/uso terapêutico , Ultrassonografia
12.
Artigo em Polonês | MEDLINE | ID: mdl-12818076

RESUMO

Hashimoto's thyroiditis (HT) and Graves' disease (GD) constitute a spectrum of autoimmune thyroid diseases (AITD). They share an autoimmune pathogenesis, with a cellular and a humoral response to the thyroid gland. As a consequence, dysfunction of the gland itself may develop, characterized by hyperfunction in the case of GD and hypofunction in the case of HT, however at the onset of HT the hyperthyroidism might be observed as a result of a rapid destruction of thyrocytes. An abnormal thyroid echographic pattern characterized by a diffuse low echogeneity has been described in both AITD. This hypoechogeneity is due to three components: increase of intrathyroidal flow, functional changes in thyroid follicles with increased cellularity and decrease of the colloid content, resulting in the reduction of the cell/colloid interface, variable degree of lymphocytic infiltration. The first two components may be reversible during medical treatment and seem to be characteristic for GD, whereas lymphocytic infiltration may rather represent mostly HT. Here we present a 17-year-old girl with typical clinical signs of hyperthyroidism [firm goiter (II degrees), tachycardia, palpitations, nervousness, excessive sweating and tremor]. Laboratory tests were the following: fT3 - 6.59 pg/ml(increasing), fT4 - 1.99 ng/dl(increasing), TSH - 0.02 micro IU/ml(decreasing); anti-Tg-Ab - 840 IU/ml(increasing), anti-TPO-Ab - 190 IU/ml(increasing) (4 months later antithyroid antibodies were 2200 and 70, respectively). Ultrasound examination showed hypoechogeneity of the whole gland and enhanced vascular flow based on power Doppler analysis. Thyroid scan visualized the generally increased uptake of technetium. The girl was put on beta-blocker (propranolol) and later an antithyroid drug (thiamazole) was added. A course of disease was unstable, therefore the fine-needle aspiration biopsy was performed and showed the presence of single groups of normal thyrocytes and scanty colloid with no features of HT. Power Doppler analysis showed still enhanced blood flow within a gland inspite of euthyroid state. After a very unsteady period of the disease, the euthyroid state is maintained although the medical treatment was given up. The full recovery of normal blood flow and normal echogeneity of the thyroid was documented. The latter supports the diagnosis of GD. Follow-up of the thyroid echogeneity is of great diagnostic and prognostic value if the assay of TSHR-Ab is not available. On the other side, it has to be remembered that TSHR-Ab do not have to be positive in patients with GD and can be positive in patients with HT.

13.
Artigo em Polonês | MEDLINE | ID: mdl-12818080

RESUMO

Five children with a solitary hot thyroid nodule are described in this paper. The clinical status, hormonal values, thyroid ultrasound, pre-operative cytological examination and post-operative histological evaluation are analyzed. A special attention has been directed toward the distribution of radioisotope in scintiscan of the presented cases.

14.
Artigo em Polonês | MEDLINE | ID: mdl-12818087

RESUMO

Four rare cases of precocity in children are described in this paper. Three of them presented some clinical features of McCune-Albright syndrome and the fourth one was a severely hypothyroid child with breast enlargement. The most likely causes of precocious sexual development in these children have been studied.

15.
Andrologia ; 31(3): 157-61, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10363120

RESUMO

For studies addressing the functions of Leydig cells, isolated cells are often better suited than intact animals. Here, the isolation procedure of Leydig cells from adult male Djungarian hamsters (Phodopus sungorus) is described. Cells were isolated using a procedure involving enzymatic dissociation and Percoll-gradient centrifugation. For each experiment, approximately 4.4 x 10(6) Leydig cells from six animals were obtained. The cells showed high steroidogenic responsiveness to physiological (ovine luteinizing hormone (oLH) and human chorionic gonadotropin (hCG)) and nonphysiological (forskolin) stimuli in vitro. Approximately 98% of cells were viable as assessed by trypan blue exclusion, and the purity varied from 80 to 95% as tested by 3 beta-hydroxysteroid dehydrogenase activity. Leydig cells were also identified by a bright yellow halo under phase-contrast microscopy. They contained numerous lipid droplets and showed round nuclei and prominent nucleoli. The cells responded to oLH, hCG and forskolin with an increased testosterone production in a dose-dependent manner. Dose-response curves in these studies suggest that Leydig cells of Djungarian hamsters undergo desensitization, probably due to down regulation of their LH/CG receptors.


Assuntos
Separação Celular/métodos , Células Intersticiais do Testículo/citologia , Testosterona/biossíntese , Animais , Gonadotropina Coriônica/metabolismo , Gonadotropina Coriônica/farmacologia , Colforsina/metabolismo , Colforsina/farmacologia , Cricetinae , Relação Dose-Resposta a Droga , Humanos , Células Intersticiais do Testículo/efeitos dos fármacos , Células Intersticiais do Testículo/metabolismo , Hormônio Luteinizante/metabolismo , Hormônio Luteinizante/farmacologia , Masculino , Phodopus , Ovinos
16.
Artigo em Polonês | MEDLINE | ID: mdl-12818094

RESUMO

17-year-old girl with thyroid tumor of the right lobe is described in this paper. Based on clinical picture and diagnostic criteria the follicular adenoma was suspected pre-operatively as the most likely final diagnosis. Post-operative histopathological evaluation proved the presence of the oxyphilic type of follicular thyroid cancer within the follicular adenoma. The authors analyze the possibilities of the pre-operative discovery of the discussed cancer.

17.
Neurosci Lett ; 201(3): 247-50, 1995 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-8786851

RESUMO

Leydig cells of adult Djungarian hamsters, stimulated with luteinizing hormone (LH), were co-incubated with melatonin at various concentrations in a primary culture system. Testosterone secretion was only affected by melatonin when cells were stimulated with LH. Maximal suppression was observed at low doses of LH (0.5 ng/ml). These effects are at least partially mediated through the adenylate cyclase system, since melatonin was able to reduce forskolin-stimulated testosterone secretion. These results indicate that the time between pulses of LH can be considered to be most highly effective for tonic melatonin actions.


Assuntos
Células Intersticiais do Testículo/efeitos dos fármacos , Melatonina/farmacologia , Testosterona/sangue , Testosterona/metabolismo , Animais , Colforsina/farmacologia , Cricetinae , Relação Dose-Resposta a Droga , Técnicas In Vitro , Hormônio Luteinizante/farmacologia , Masculino
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