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1.
J Endocrinol Invest ; 41(12): 1435-1443, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30327945

RESUMEN

Thyroid ultrasonography (US) is the gold standard for thyroid imaging and its widespread use is due to an optimal spatial resolution for superficial anatomic structures, a low cost and the lack of health risks. Thyroid US is a pivotal tool for the diagnosis and follow-up of autoimmune thyroid diseases, for assessing nodule size and echostructure and defining the risk of malignancy in thyroid nodules. The main limitation of US is the poor reproducibility, due to the variable experience of the operators and the different performance and settings of the equipments. Aim of this consensus statement is to standardize the report of thyroid US through the definition of common minimum requirements and a correct terminology. US patterns of autoimmune thyroid diseases are defined. US signs of malignancy in thyroid nodules are classified and scored in each nodule. We also propose a simplified nodule risk stratification, based on the predictive value of each US sign, classified and scored according to the strength of association with malignancy, but also to the estimated reproducibility among different operators.


Asunto(s)
Enfermedades de la Tiroides/diagnóstico por imagen , Glándula Tiroides/diagnóstico por imagen , Ultrasonografía/normas , Consenso , Humanos , Reproducibilidad de los Resultados
2.
J Endocrinol Invest ; 41(7): 849-876, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29729004

RESUMEN

BACKGROUND: Thyroid nodules are a common clinical problem, and differentiated thyroid cancer is becoming increasingly prevalent. METHODS: Six scientific Italian societies entitled to cure thyroid cancer patients (the Italian Thyroid Association, the Medical Endocrinology Association, the Italian Society of Endocrinology, the Italian Association of Nuclear Medicine and Molecular Imaging, the Italian Society of Unified Endocrine Surgery and the Italian Society of Anatomic Pathology and Diagnostic Cytology) felt the need to develop a consensus report based on significant scientific advances occurred in the field. OBJECTIVE: The document includes recommendations regarding initial evaluation of thyroid nodules, clinical and ultrasound criteria for fine-needle aspiration biopsy, initial management of thyroid cancer including staging and risk assessment, surgical management, radioiodine remnant ablation, and levothyroxine therapy, short-term and long-term follow-up strategies, and management of recurrent and metastatic disease. The objective of this consensus is to inform clinicians, patients, researchers, and health policy makers about the best strategies (and their limitations) relating to the diagnosis and treatment of differentiated thyroid cancer.


Asunto(s)
Adenocarcinoma/diagnóstico , Adenocarcinoma/terapia , Endocrinología/normas , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/terapia , Biopsia con Aguja Fina/métodos , Biopsia con Aguja Fina/normas , Consenso , Humanos , Italia , Imagen Molecular/métodos , Imagen Molecular/normas , Medicina Nuclear/organización & administración , Medicina Nuclear/normas , Cintigrafía/métodos , Cintigrafía/normas , Sociedades Médicas/organización & administración , Sociedades Médicas/normas , Ultrasonografía/métodos , Ultrasonografía/normas
3.
Oncogene ; 36(5): 667-677, 2017 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-27375021

RESUMEN

The transdifferentiation of epithelial cells toward a mesenchymal condition (EMT) is a complex process that allows tumor cells to migrate to ectopic sites. Cadherins are not just structural proteins, but they act as sensors of the surrounding microenvironment and as signaling centers for cellular pathways. However, the molecular mechanisms underlying these signaling functions remain poorly characterized. Cadherin-6 (CDH6) is a type 2 cadherin, which drives EMT during embryonic development and it is aberrantly re-activated in cancer. We recently showed that CDH6 is a TGFß target and an EMT marker in thyroid cancer, suggesting a role for this protein in the progression of this type of tumor. Papillary thyroid carcinomas (PTCs) are usually indolent lesions. However, metastatic spreading occurs in about 5% of the cases. The identification of molecular markers that could early predict the metastatic potential of these lesions would be strategic to design more tailored approaches and reduce patients overtreatment. In this work, we assessed the role of CDH6 in the metastatic progression of thyroid cancer. We showed that loss of CDH6 expression profoundly changes cellular architecture, alters the inter-cellular interaction modalities and attenuates EMT features in thyroid cancer cells. Using a yeast two-hybrid screening approach, based on a thyroid cancer patients library, we showed that CDH6 directly interacts with GABARAP, BNIP3 and BNIP3L, and that through these interactions CDH6 restrains autophagy and promotes re-organization of mitochondrial network through a DRP1-mediated mechanism. Analysis of the LIR domains suggests that the interaction with the autophagic machinery may be a common feature of many cadherin family members. Finally, the analysis of CDH6 expression in a unique cohort of human PTCs showed that CDH6 expression marks specifically EMT cells. and it is strongly associated with metastatic behavior and worse outcome of PTCs.


Asunto(s)
Cadherinas/metabolismo , Carcinoma/metabolismo , Carcinoma/patología , Neoplasias de la Tiroides/metabolismo , Neoplasias de la Tiroides/patología , Autofagia/fisiología , Carcinoma Papilar , Transición Epitelial-Mesenquimal , Humanos , Metástasis de la Neoplasia , Transducción de Señal , Cáncer Papilar Tiroideo
4.
J Oncol ; 2012: 320198, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22934111

RESUMEN

The aim of this study was to assess the efficacy of PRRT in patients with advanced neuroendocrine tumors (NETs). Patients and Methods. From January 2007 to August 2011, we enrolled 65 patients (m/f 38/27; mean age 65 years, range 33-83) with advanced NETs having enhanced SSTR expression, treated with PRRT. The enhanced expression of SSTR was assessed using (68)Ga-DOTATOC/DOTATATE PET/CT. Among all the enrolled patients, 6 of them were excluded from the present analysis since they voluntarily interrupted treatment. Mean activity/cycle of 2.6 GBq ((90)Y-DOTATOC/DOTATATE) or 6.0 GBq ((177)Lu-DOTATOC/DOTATATE) was administrated intravenously (max 9 cycles). Results. Complete response (CR) was found in 1/59 (2%) patients, partial remission (PR) in 24/59 (40.5%) patients, stable disease (SD) in 24/59 (40.5%), and progression (PD) in 10/59 (17%) patients. The overall tumor response rate (CR + PR) was 42.5%. In 40.5% of patients, the disease could be stabilized. Overall, 49 out of 59 patients had no tumor progression (83%). Twelve patients out of 59 (20%) had grade 2-3 hematological side effects including anemia, thrombocytopenia, and leukopenia. Long-term nephrotoxicity was observed in 3 patients (2 moderate, 1 severe). Conclusions. PRRT is a promising perspective for patients with advanced NETs.

5.
Cytopathology ; 22(3): 164-73, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20626438

RESUMEN

OBJECTIVE: Fine needle aspiration (FNA) has long been recognized as an essential technique for the evaluation of thyroid nodules. Although specific cytological patterns have been recognized, a wide variety of reporting schemes for thyroid FNA results have been adopted. This study reports our experience with a five-category reporting scheme developed in-house based on a numeric score and applied to a large series of consecutive thyroid FNAs. It focuses mainly on the accuracy of thyroid FNA as a preoperative test in a large subset of histologically distinct thyroid lesions. METHODS: During the 1998-2007 period, 18,359 thyroid ultrasound-guided FNAs were performed on 15,269 patients; FNA reports were classified according to a C1-C5 reporting scheme: non-diagnostic (C1), benign (C2), indeterminate (C3), suspicious (C4), and malignant (C5). RESULTS: Non-diagnostic (C1) and indeterminate (C3) FNA results totalled 2,230 (12.1%) and 1,461 (7.9%), respectively, while suspicious (C4) and malignant (C5) results totalled 238 (1.3%) and 531 (2.9%), respectively. Histological results were available in 2,047 patients, with thyroid malignancy detected in 840. Positive predictive value of FNA was 98.1% with a 49.0 likelihood ratio (LR) of malignancy in patients with a C4/C5 FNA report. CONCLUSIONS: This five-category scheme for thyroid FNA is accurate in discriminating between the virtual certainty of malignancy associated with C5, a high rate (92%) of malignancy associated with C4, and a 98% probability of a histological benign diagnosis associated with C2. Further sub-classifications of C3 may improve the accuracy of the diagnostic scheme and may help in recognizing patients eligible for a 'wait and see' management.


Asunto(s)
Informe de Investigación , Glándula Tiroides/patología , Biopsia con Aguja Fina , Humanos , Estadificación de Neoplasias , Neoplasias de la Tiroides/patología
6.
Thyroid ; 11(10): 941-6, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11716041

RESUMEN

Conventional cytology cannot discriminate between benign and malignant follicular neoplasms. Our study evaluated the diagnostic role of computer-assisted image analysis in the presurgical assessment of thyroid follicular neoplasms. Fifty-eight patients (14 males, 44 females, age range, 45-75 years) who underwent surgery for cytologic diagnosis of thyroid follicular neoplasm were studied. All patients were first evaluated on clinical grounds and assigned a high/low suspicion of malignancy on the basis of gender, age, and nodule size. Cell image analysis was subsequently performed using a Cytometrica BYK Gulden microscope image processor on Feulgen-stained thyroid cytologic smears. A different population of 50 benign and 50 malignant, histologically evaluated nodules was studied in order to establish image analysis criteria suggestive of thyroid malignancy. Ploidy histogram, proliferation index (PI), nuclear area coefficient of variation (NACV), and anisocariosis ratio (AR) were studied. Thyroid cancer was diagnosed in 16 of 58 follicular neoplasms. Only 7 of these lesions were clinically suspicious (43.7%), whereas 14 of 16 (87.5%) malignant tumors were identified by image analysis. Positive and negative predictive values of image analysis versus clinical evaluation were 46.6% versus 30.4% and 92.8% versus 74.3%, respectively. The distribution of ploidy pattern was different in benign versus malignant follicular neoplasms (chi2 8.25, p = 0.016), malignant lesions showing an increased frequency of heteroclonal aneuploid DNA content (37.5% vs. 7.1%). Increased PI (mean +/- standard deviation (SD) = 11.3 +/- 5.7 vs. 7.1 +/- 6.1; p < 0.01) and NACV (mean +/- SD = 25.28 +/- 1.89 vs. 20.14 0.91; p < 0.01) levels were also observed in malignant follicular neoplasms. In conclusion, computer-assisted image analysis may profitably support clinical evaluation in the assessment of thyroid follicular neoplasms.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Ploidias , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Adenoma/diagnóstico , Adenoma/genética , Adenoma/patología , Adulto , Anciano , Aneuploidia , Biopsia con Aguja , Carcinoma Papilar Folicular/diagnóstico , Carcinoma Papilar Folicular/genética , Carcinoma Papilar Folicular/patología , Estudios de Casos y Controles , Núcleo Celular/patología , ADN de Neoplasias/análisis , ADN de Neoplasias/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice Mitótico , Valor Predictivo de las Pruebas , Neoplasias de la Tiroides/diagnóstico
7.
Clin Endocrinol (Oxf) ; 52(2): 187-95, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10671946

RESUMEN

OBJECTIVE: Insulin-like growth factor binding-protein-1 (IGFBP-1) has a role in glucose homeostasis and is present at high concentrations in hyperthyroidism. We have investigated the relationship between IGFBP-1 concentration and glucose homeostasis in hyperthyroidism. DESIGN: Patients and controls had intravenous glucose tolerance tests (IVGTT) and/or oral glucose tolerance tests (OGTT). Patients were tested when hyperthyroid and when euthyroid whilst the controls were tested once. The IVGTT was used to assess insulin sensitivity and the OGTT to establish that the study group had abnormal glucose tolerance. The hyperthyroid patients were treated with methimazole to restore euthyroidism. PATIENTS: Ten patients (9 females) and 13 healthy controls (9 females) consented to the study. Ten patients and nine controls (7 females) had IVGTT. Six patients (5 females) and six controls (4 females) had OGTT. MEASUREMENTS: Glucose, insulin, glucagon, GH and IGFBP-1 were measured during GTT. IGF-I, free thyroid hormones, and TSH concentrations were measured basally. RESULTS: Hyperthyroid subjects were insulin resistant and 67% had impaired glucose tolerance. Fasting IGFBP-1 levels were doubled in hyperthyroid subjects compared to healthy controls and correlated positively with free T4 (r = 0.84, P < 0.0001), with peak glucose during the OGTT (r = 0.68, P < 0.005) with peak insulin during the IVGTT (r = 0.51, P < 0.005) and negatively with glucose disappearance constant (r = - 0.52, P < 0.005). IGFBP-1 was highly phosphorylated in hyperthyroid and control subjects. Fasting insulin and IGFBP-1 levels were unrelated but IGFBP-1 suppressed acutely during GTT in all groups. GH levels fell less in patients with hyperthyroidism than in normals during GTTs. CONCLUSIONS: We conclude that in hyperthyroidism thyroid hormones directly increase fasting IGFBP-1 concentration but acute regulation of IGFBP-1 by insulin is normal and that elevated fasting phosphorylated IGFBP-1 concentration is associated with insulin resistance.


Asunto(s)
Hipertiroidismo/metabolismo , Resistencia a la Insulina , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Adulto , Antitiroideos/uso terapéutico , Área Bajo la Curva , Glucemia/metabolismo , Estudios de Casos y Controles , Femenino , Prueba de Tolerancia a la Glucosa , Hormona de Crecimiento Humana/sangre , Humanos , Hipertiroidismo/tratamiento farmacológico , Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Metimazol/uso terapéutico , Tiroxina/sangre
8.
J Endocrinol Invest ; 22(10): 796-9, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10614530

RESUMEN

We report two patients with incidentally discovered enlarged parathyroid glands while performing neck ultrasonography (US) for thyroid nodules. The parathyroid masses were seen as hypoechoic, homogeneous, oval nodules, separated from the thyroid gland. Both patients were completely asymptomatic, although subclinical evidence of hyperparathyroidism (serum PTH and calcium levels in the upper limit of the normal range, increased ionized serum calcium, osteocalcin, urinary calcium and hydroxyproline) was subsequently found in one patient. An enhanced uptake on sesta-MIBI scinti scan was concordant with the US finding in the two cases. PTH levels in the wash-out from the US-guided fine needle aspiration biopsy, confirmed the parathyroid origin of the lesions. Cytology and immunocytochemistry were, in our cases, unreliable diagnostic procedures. The extensive use of US imaging in thyroid pathology may increase the finding of US incidentally discovered parathyroid adenomas. The early detection of silent parathyroid pathologic findings may extend the natural history of these masses to a preclinical stage. Further investigations are necessary to evaluate the evolution of parathyroid incidentalomas and therefore their clinical significance.


Asunto(s)
Neoplasias de las Paratiroides/diagnóstico por imagen , Glándula Tiroides/diagnóstico por imagen , Calcio/sangre , Calcio/orina , Femenino , Humanos , Hidroxiprolina/sangre , Persona de Mediana Edad , Osteocalcina/sangre , Hormona Paratiroidea/sangre , Ultrasonografía
9.
J Clin Ultrasound ; 27(9): 492-8, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10525210

RESUMEN

PURPOSE: The aim of our study was to evaluate the incidence of incidentally found parathyroid adenomas (incidentalomas) in patients undergoing sonography of the neck for thyroid disease. METHODS: A total of 1,686 patients (305 men and 1,381 women) underwent sonography of the neck; the mean age was 49.6 +/- 21.7 years. In 38 patients (2.3%; 7 men and 31 women) with a mean age of 48.7 +/- 14.7 years, hypoechoic, homogeneous, oval nodules (mean volume, 1.0 +/- 0. 9 cm(3)) adjacent to the thyroid parenchyma were observed. All these lesions, compatible with the shape of an enlarged parathyroid gland, underwent ultrasound-guided fine-needle aspiration biopsy (FNAB), with measurement of parathyroid hormone (PTH) and thyroglobulin (Tg) levels in the needle washings (FNAB-PTH and FNAB-Tg). Biochemical screening for hyperparathyroidism was also performed. RESULTS: Cytologic examination plus FNAB-PTH/FNAB-Tg measurements revealed the presence of cellular material consistent with parathyroid tissue in 9 patients (24%), thyroid tissue in 22 patients (58%), and lymphoid tissue in 4 patients (11%). A tissue diagnosis was not established in 3 patients (8%). Five of 9 patients with parathyroid enlargement had high serum PTH and calcium levels. CONCLUSIONS: Enlarged parathyroid glands may be incidentally discovered during sonography of the thyroid. In patients with thyroid disease, the positive-predictive value of sonography in the identification of parathyroid tissue was low. Ultrasound-guided FNAB-PTH determination should be carried out when parathyroid adenoma is suspected. The incidental finding of an enlarged parathyroid may or may not be associated with yet undiagnosed hyperparathyroidism.


Asunto(s)
Adenoma/diagnóstico por imagen , Neoplasias de las Paratiroides/diagnóstico por imagen , Adenoma/sangre , Adenoma/patología , Adulto , Biopsia con Aguja , Calcio/sangre , Diagnóstico Diferencial , Femenino , Humanos , Hiperparatiroidismo/sangre , Hiperparatiroidismo/diagnóstico por imagen , Hiperparatiroidismo/patología , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Neoplasias de las Paratiroides/sangre , Neoplasias de las Paratiroides/patología , Estudios Retrospectivos , Sensibilidad y Especificidad , Tiroglobulina/sangre , Ultrasonografía
10.
Thyroid ; 9(2): 105-11, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10090308

RESUMEN

The identification of metastatic neck lymph nodes in patients awaiting surgery for differentiated thyroid tumor permits their excision during thyroidectomy. In order to detect thyroid cancer lymphatic metastasis before surgery, we measured thyroglobulin (Tg) in the needle wash-out of fine-needle aspiration biopsy (FNAB). Ultrasound-guided FNAB on enlarged neck nodes was performed in 23 patients awaiting surgery for differentiated thyroid tumor (n = 33 lymph nodes), 47 patients previously thyroidectomized for thyroid tumor (n = 89 lymph nodes), and 60 patients without thyroid disease (n = 94 lymph nodes). Immediately after aspiration biopsy, the needle was rinsed with 1 mL of normal saline solution and Tg levels were measured on the needle wash-out (FNAB-Tg). FNAB-Tg levels were markedly elevated in metastatic lymph nodes both in patients awaiting thyroidectomy (metastatic vs. negative lymph nodes, mean +/- SEM, 16,593 +/- 7,050 ng/mL vs. 4.91 +/- 1.61 ng/mL; p < 0.001) and in thyroidectomized patients (11,541 +/- 7,283 ng/mL vs. 0.45 +/- 0.07 ng/mL; p < 0.001). FNAB-Tg sensitivity, evaluated through histological examination in 69 lymph nodes, was 84.0%. The combination of cytology plus FNAB-Tg increased FNAB sensitivity from 76% to 92.0%. In conclusion, FNAB-Tg measurement is a useful technique for early diagnosis of lymph node metastasis originating from differentiated thyroid cancer.


Asunto(s)
Biopsia con Aguja , Ganglios Linfáticos/química , Metástasis Linfática , Tiroglobulina/análisis , Neoplasias de la Tiroides/química , Adulto , Anciano , Diferenciación Celular , Femenino , Humanos , Ganglios Linfáticos/patología , Ganglios Linfáticos/cirugía , Masculino , Persona de Mediana Edad , Cuello , Sensibilidad y Especificidad , Tiroglobulina/sangre , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/cirugía , Tiroidectomía
11.
Neurosci Lett ; 277(3): 169-72, 1999 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-10626840

RESUMEN

We have studied nicotinic acetylcholine receptors in spontaneously hypertensive 'stroke prone' (SHsp) rats. We found a significant decrease in 125I-alpha-bungarotoxin binding and alpha7 subunit mRNA levels in cortical areas of the SHsp rats with respect to Wistar Kyoto (WKy) normotensive rats. Antihypertensive drug treatment counteracted these changes in cerebral cortex but not in hippocampus. No significant change was instead found in [3H]-epibatidine binding and alpha4 and beta2 subunit mRNA levels. SHsp rats showed decreased latency at the active avoidance test and transiently increased threshold at both hot-plate and tail-flick tests in comparison with WKy rats. None of these behavioral parameters was correlated with 125I-alpha-bungarotoxin binding in cortical areas. In conclusion, present data show a preferential impairment of alpha-bungarotoxin sensitive nAChRs in SHsp rats.


Asunto(s)
Nicotina/metabolismo , ARN Mensajero/metabolismo , Ratas Endogámicas SHR/metabolismo , Receptores Nicotínicos/genética , Animales , Antihipertensivos/farmacología , Reacción de Prevención/fisiología , Bungarotoxinas/metabolismo , Corteza Cerebral/metabolismo , Predisposición Genética a la Enfermedad , Hipocampo/metabolismo , Masculino , Umbral del Dolor , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Ratas , Ratas Endogámicas SHR/genética , Ratas Endogámicas WKY , Tiempo de Reacción , Receptores Nicotínicos/metabolismo , Valores de Referencia , Accidente Cerebrovascular/genética
12.
J Endocrinol Invest ; 18(5): 384-90, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7594229

RESUMEN

The distribution of glucocorticoid receptor (GR) in the rat testis was investigated by means of immunocytochemistry (IR) and computer-assisted image analysis. A monoclonal antibody against rat liver GR showed the presence of GR IR selectively in the nuclei of interstitial and tubular cells. The semiquantitative microdensitometry of GR IR revealed that 77% of the specific staining was localized in the tubular compartment of rat testis. After adrenalectomy, GR IR was greatly reduced both in interstitial and tubular cells, roughly at the same degree. Corticosterone treatment (50 mg/kg, for 5 d) of adrenalectomized animals yielded a recovery of nuclear immunopositivity without changing the cellular distribution of GR, as observed in control rats. Nevertheless, the high dose of corticosterone administered produced a significant (p < 0.01) decrease of GR IR with respect to control rats. These results provide evidence for a prevalent nuclear binding of GR in the tubular compartment in basal conditions. On the other hand, adrenalectomy or repeated corticosterone treatment seem to affect GR similarly in all positive cells without changing significantly the proportion of GR IR in the different testicular compartments. This uneven distribution of GR IR suggests that tubular cells can be a major target of corticosterone when affecting directly testicular functions in the rat.


Asunto(s)
Adrenalectomía , Corticosterona/farmacología , Receptores de Glucocorticoides/metabolismo , Testículo/metabolismo , Animales , Anticuerpos Monoclonales , Núcleo Celular/efectos de los fármacos , Núcleo Celular/metabolismo , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Masculino , Ratas , Ratas Sprague-Dawley , Receptores de Glucocorticoides/efectos de los fármacos , Testículo/efectos de los fármacos , Testículo/ultraestructura
13.
Int J Androl ; 18(1): 46-54, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7782131

RESUMEN

Short- (3-24 h) and long-term (4-50 days) changes in sulphated glycoprotein-2 (SGP-2) and ornithine decarboxylase (ODC) mRNA levels in the adult rat testis were studied following a single dose of ethane-dimethane sulphonate (EDS), to destroy the Leydig cells. Distribution patterns of SGP-2 and ODC labelling were consistent with prevailing expression of the two transcripts in Sertoli cells and germ cells, respectively. This pattern did not show appreciable changes following EDS administration. No labelling of SGP-2 mRNA was noted in the interstitium of control and EDS-treated rats. This finding indicates that Leydig cell death induced by EDS is not associated with increased SGP-2 mRNA levels, a phenomenon related to apoptotic cell death in many tissues. Semi-quantitative densitometric analysis of the preparations demonstrated differential changes in SGP-2 and ODC mRNA levels in the tubular compartment following EDS treatment. At 6, but not at 3 and 12, h following EDS administration, SGP-2 mRNA levels showed a significant increase, possibly secondary to a direct effect of the alkylating agent on Sertoli cells. A significant decrease in ODC mRNA levels was observed from day 7 to day 28, matching degenerative changes in the seminiferous epithelium. In contrast, a decrease in SGP-2 transcript levels was observed from days 21-35 after treatment. In conclusion, our findings demonstrate that SGP-2 mRNA, a putative marker of apoptosis, is not altered in the testicular interstitium during EDS-induced degeneration of Leydig cells.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Apoptosis , Glicoproteínas/metabolismo , Células Intersticiales del Testículo/metabolismo , Chaperonas Moleculares , Ornitina Descarboxilasa/metabolismo , Testículo/metabolismo , Animales , Apoptosis/efectos de los fármacos , Secuencia de Bases , Clusterina , Sondas de ADN , Células Intersticiales del Testículo/efectos de los fármacos , Masculino , Mesilatos/farmacología , Datos de Secuencia Molecular , Ornitina Descarboxilasa/genética , Ratas , Ratas Sprague-Dawley , Testículo/citología , Factores de Tiempo
14.
Neurobiol Aging ; 16(1): 77-83, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-7723939

RESUMEN

By means of semiquantitative immunocytochemistry, possible age-related changes in dopamine and cyclic AMP-regulated phosphoprotein mr 32 (DARPP-32) and glial fibrillary acidic protein (GFAP) immunoreactivities (IR) were investigated in tanycytes of the arcuate nucleus. These two markers showed opposite changes during aging. DARPP-32 IR decreased by around 70%, whereas GFAP IR increased by around 300% in 24-month-old vs. 3-month-old rats. These changes were accompanied by a progressive loss in the number of tanycytes, measured by counting of their long processes in the arcuate nucleus. No significant age-related change was observed either in GFAP IR in astrocytic populations of the mediobasal hypothalamus or in tyrosine hydroxylase IR in dopaminergic neurons of the dorsal arcuate nucleus. These observations indicate that the tanycytic population of the arcuate nucleus undergoes important modifications during aging, which include cell loss, impairment in the intracellular signalling cascade linked to DARPP-32, and hypertrophy. These changes may be related to the alterations in the neuroendocrine systems known to occur during aging.


Asunto(s)
Envejecimiento/patología , Hipotálamo Medio/patología , Envejecimiento/metabolismo , Animales , Núcleo Arqueado del Hipotálamo/metabolismo , Núcleo Arqueado del Hipotálamo/patología , Astrocitos/metabolismo , Fosfoproteína 32 Regulada por Dopamina y AMPc , Proteína Ácida Fibrilar de la Glía/metabolismo , Hipotálamo Medio/citología , Hipotálamo Medio/metabolismo , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Masculino , Proteínas del Tejido Nervioso/metabolismo , Núcleo Hipotalámico Paraventricular/patología , Fosfoproteínas/metabolismo , Ratas , Ratas Sprague-Dawley , Tirosina 3-Monooxigenasa/metabolismo
15.
Biochem Biophys Res Commun ; 202(3): 1315-21, 1994 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-8060308

RESUMEN

The seminiferous epithelium is a highly proliferating tissue in which germ cell "degeneration" is a constant feature. Recent data based on morphological analysis have shown that spontaneously dying germ cells display some characteristics of apoptosis. In order to evaluate the molecular signals controlling the phenomenon, adult male rats were studied after in vivo treatment with ethane dimethane sulphonate, an agent which leads to testosterone withdrawal by a selective destruction of Leydig cells. DNA fragmentation by agarose gel electrophoresis and cell DNA content by flow cytometry after propidium iodide staining were used to evaluate and quantify apoptosis in the testis. Despite the simultaneous presence of cells with different ploidies, the present data suggest that testosterone withdrawal induces death by apoptosis and that this phenomenon is particularly evident in haploid germ cells. Thus, this study support the involvement of testosterone in regulating programmed cell death, beside cell proliferation and differentiation, during spermatogenesis.


Asunto(s)
Apoptosis , Espermatogénesis , Testosterona , Animales , Electroforesis en Gel de Agar , Citometría de Flujo , Células Intersticiales del Testículo/efectos de los fármacos , Células Intersticiales del Testículo/metabolismo , Células Intersticiales del Testículo/patología , Masculino , Mesilatos/farmacología , Modelos Biológicos , Ratas , Ratas Sprague-Dawley
16.
Neurochem Int ; 25(1): 17-22, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7950964

RESUMEN

Basic fibroblast growth factor (bFGF) increases neuronal survival and growth in cell cultures and stimulates functional recovery from brain lesion. In addition, bFGF is able to induce glial cell proliferation and differentiation. Recently, L-deprenyl has been shown to potentiate astrocyte reaction to a mechanical lesion and to possess a trophic-like activity in several experimental models. In the present paper, we have therefore investigated if the enhancing effect of L-deprenyl on astrocyte reactivity is accompanied by increased levels of bFGF. The effect of L-deprenyl (0.25 mg/kg/day) on bFGF immunoreactivity (IR) after the insertion of an injection cannula in rat neostriatum have been investigated. It has been found that subchronic L-deprenyl treatment potentiates both the lesion-induced increase of glial fibrillary acidic protein (GFAP) and bFGF IRs (P < 0.01). These data suggest that a possible mechanism for L-deprenyl-induced neuroprotection may be the activation of astrocytes associated with increased secretion of trophic factors that promote neuronal survival and growth. This "astrocyte-kinetic" action of L-deprenyl could represent a new therapeutical approach to increase trophic support of lesioned neurons.


Asunto(s)
Astrocitos/efectos de los fármacos , Enfermedades del Sistema Nervioso/tratamiento farmacológico , Selegilina/farmacología , Animales , División Celular/efectos de los fármacos , Densitometría , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Proteína Ácida Fibrilar de la Glía/metabolismo , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Masculino , Neostriado/anatomía & histología , Neostriado/fisiología , Degeneración Nerviosa/efectos de los fármacos , Enfermedades del Sistema Nervioso/patología , Ratas , Ratas Sprague-Dawley
17.
Pharmacol Biochem Behav ; 45(3): 607-14, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8101377

RESUMEN

Transient forebrain ischemia induced in rats by the four-vessel occlusion method produced analgesic effects in the hotplate test that persisted for 2 weeks. Ischemia-induced analgesia was attenuated by low doses of alpha 2-agonist clonidine (0.01-0.10 mg/kg, IP) and enhanced by low doses of alpha 2-antagonists yohimbine (1-2 mg/kg, IP) and idazoxan (0.25-1.00 mg/kg, IP) administration 7 days after ischemia. Ischemia-induced analgesia was not affected by methysergide, naloxone, propranolol, or phenoxybenzamine administered 7 days after ischemia, when motor control and arousal level of rats recovered to normal conditions. The enhanced response to yohimbine was antagonized by pretreatment with clonidine (0.75 mg/kg, IP) and naloxone (10 mg/kg, IP), suggesting the involvement of endogenous opioid peptides. The enhanced response to yohimbine was still present 2 months after ischemia, when preischemic hotplate threshold was restored. As alpha 2-agonists reduce and alpha 2-antagonists increase the outflow of central noradrenaline, it is suggested that activation of central noradrenergic systems is involved in the mediation of ischemia-induced analgesia.


Asunto(s)
Analgesia , Ataque Isquémico Transitorio/psicología , Receptores Adrenérgicos alfa/fisiología , Antagonistas Adrenérgicos alfa/farmacología , Animales , Encéfalo/patología , Arteria Carótida Común/fisiología , Clonidina/farmacología , Dioxanos/farmacología , Endorfinas/fisiología , Idazoxan , Ataque Isquémico Transitorio/patología , Masculino , Metisergida/farmacología , Naloxona/farmacología , Norepinefrina/fisiología , Dimensión del Dolor/efectos de los fármacos , Umbral del Dolor/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Receptores Adrenérgicos alfa/efectos de los fármacos , Serotonina/fisiología , Transmisión Sináptica/efectos de los fármacos , Yohimbina/farmacología
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