RESUMEN
The ADA and the EASD recently published a consensus statement for the medical management of hyperglycaemia in patients with type 2 diabetes. The authors advocate initial treatment with metformin monotherapy and lifestyle modification, followed by addition of basal insulin or a sulfonylurea if glycaemic goals are not met (tier 1 recommendations). All other glucose-lowering therapies are relegated to a secondary (tier 2) status and only recommended for selected clinical settings. In our view, this algorithm does not offer physicians and patients the appropriate selection of options to individualise and optimise care with a view to sustained control of blood glucose and reduction both of diabetes complications and cardiovascular risk. This paper critically assesses the basis of the ADA/EASD algorithm and the resulting tiers of treatment options.
Asunto(s)
Algoritmos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 2/complicaciones , Europa (Continente) , Humanos , Hiperglucemia/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Factores de Riesgo , Sociedades Médicas/normas , Estados UnidosRESUMEN
BACKGROUND: Twin studies have shown that age at menarche may be subject to hereditary influences but the specific determinants are unknown. Estrogens are known to have an important role in menarche. Since the enzyme aromatase is responsible for the conversion of androgens to estrogens, the aromatase (CYP19) gene could be a candidate gene for the regulation of menarche. The aim of this study was to investigate the possible association of the CYP19(TTTA)(n) polymorphism with age at menarche. METHODS: We studied 130 healthy adolescent females from a closed community in North-Western Greece. Information on menarche was obtained through interviews. The BMI was recorded. The CYP19(TTTA)(n) polymorphism was genotyped. RESULTS: The mean age at menarche was 12.9 ± 1.2 years and the BMI = 19.8 ± 2.3 kg/m(2). Genotype analysis revealed 5 CYP19(TTTA)(n) alleles containing 7-11 TTTA repeats. Girls homozygous for the allele with 7 TTTA repeats had earlier menarche (12.45 ± 0.9 years) than girls carrying other genotypes (13.0 ± 1.2 years, P = 0.025), whereas the BMI was not different between these two subgroups. Carriers of the allele with 11 TTTA repeats had later menarche compared with non-carriers (14.1 ± 0.75 versus 12.8 ± 1.2 years, P< 0.001), whereas no difference was found in BMI values. Comparing girls with early menarche (<12 years, 25th percentile) with girls with late menarche (>13.75 years, 75th percentile), we found that 31% of the girls with early menarche were homozygous for the (TTTA)(7) allele compared with 6.9% among girls with late menarche (P = 0.018). In addition, none of the girls carrying the (TTTA)(11) allele was found among the subgroup with early menarche, whereas 24.1% of girls with late menarche had the (TTTA)(11) allele (P = 0.001). No association between other alleles and age at menarche was found. CONCLUSIONS: There is evidence for a genetic contribution of the CYP19 gene to the age at menarche.
Asunto(s)
Aromatasa/genética , Menarquia/genética , Repeticiones de Microsatélite , Adolescente , Niño , Femenino , Humanos , Polimorfismo GenéticoRESUMEN
BACKGROUND: Polycystic ovary syndrome (PCOS) may be programmed in utero by androgen excess. Our aim was to examine the role of the sex hormone-binding globulin (SHBG) and androgen receptor (AR) gene polymorphisms, in the phenotypic expression of PCOS. METHODS: A cohort of 180 women with PCOS and 168 healthy women of reproductive age were investigated. BMI was recorded and the hormonal profile was determined on Day 3-5 of menstrual cycle. DNA was extracted from peripheral blood leucocytes and the SHBG(TAAAA)n and AR(CAG)n polymorphisms were genotyped by PCR. RESULTS: Genotype analysis revealed six SHBG(TAAAA)n alleles with 6-11 repeats and 19 AR(CAG)n alleles with 6-32 repeats, present in both PCOS and control women. Long SHBG(TAAAA)n alleles (>8 repeats) were at greater frequency in PCOS than normal women (P = 0.001), whereas short AR(CAG)n alleles (Asunto(s)
Síndrome del Ovario Poliquístico/genética
, Receptores Androgénicos/genética
, Globulina de Unión a Hormona Sexual/genética
, Adolescente
, Adulto
, Estudios de Cohortes
, Femenino
, Humanos
, Reacción en Cadena de la Polimerasa
, Polimorfismo Genético
, Receptores Androgénicos/fisiología
, Globulina de Unión a Hormona Sexual/fisiología
RESUMEN
AIM: To demonstrate any differences in the detection of herpes simplex virus type 1 and 2, cytomegalovirus, human herpes virus type 6 and 7 DNA from thyroid tissue blocks of patients with autoimmune thyroid disease and multi-nodular goiter and to propose few mechanisms, which could explain the possible role of herpesvirus infection in the development of thyroid autoimmune responses. MATERIAL-METHODS: Thyroid tissue specimens were obtained postoperatively from 4 patients with multinodular goiter and 18 patients with autoimmune thyroid disease (Graves' disease and Hashimoto thyroiditis). Herpes virus DNA was detected using polymerase chain reaction based assays. RESULTS: No statistically significant differences were observed between autoimmune thyroid disease and multinodular goiter tissue specimens concerning herpes simplex virus type 1, 2 DNA isolation (44.4% vs 0%, P=0.094), human herpes virus type 6 DNA isolation (11.1% vs 0%, P=0.48), human herpes virus type 7 DNA isolation (33.3% vs 25%, P=0.75). No CMV DNA was isolated from any tissue specimen. At least one kind of herpes virus DNA was detected in 13 out of 18 (72.22%) AITD tissue specimens and in 1 out of 4 (25%) MNG tissue specimens (P=0.01). CONCLUSIONS: Although no data are available relating the direct effect of herpes infection on thyroid epithelial cells, a better understanding of how an aberrant immune response against the thyroid gland is initiated and propagated through herpes virus infection is required. Elucidation of the underlying mechanisms may allow the development of new etiologically based therapeutic modalities.
Asunto(s)
ADN Viral/análisis , Herpesviridae/genética , Glándula Tiroides/cirugía , Glándula Tiroides/virología , Tiroiditis Autoinmune/cirugía , Tiroiditis Autoinmune/virología , Bocio Nodular/cirugía , Bocio Nodular/virología , Enfermedad de Graves/cirugía , Enfermedad de Graves/virología , Enfermedad de Hashimoto/cirugía , Enfermedad de Hashimoto/virología , Infecciones por Herpesviridae , Herpesvirus Humano 1/genética , Herpesvirus Humano 2/genética , Herpesvirus Humano 6/genética , Herpesvirus Humano 7/genética , HumanosRESUMEN
The purpose of this study was to reveal some possible factors for the differences between the pattern of disappearance of thyroglobulin autoantibodies (anti-Tg) and thyroid peroxidase autoantibodies (anti-TPO) in patients with differentiated thyroid carcinoma following thyroidectomy and iodine-131 ablation. Patients with a history of follicular cell derived cancer (papillary, follicular, both papillary and follicular, Hürthle cell) and high pre-operative titers of anti-TPO and/or anti-Tg autoantibodies were retrospectively studied. Thyroglobulin (Tg) levels were measured using radio-immunometric assay (RIA). Anti-Tg and anti-TPO levels during the first 6 yr' follow-up were measured by passive agglutination, during the following 10 yr by ELISA method and during the last 2 yr by chemiluminescence assay. A statistically significant difference was observed between median time (72 months) of disappearance of anti-TPO and median time (39 months) of disappearance of anti-Tg in patients with complete ablation of thyroid tissue, following iodine-131 administration (p=0.0395, Logrank statistic=4.24, Kaplan-Meier method). A statistically significant difference was observed between median time (106 months) of disappearance of anti-TPO and median time (33 months) of disappearance of anti-Tg in patients >45 yr of age (p=0.034) and between median time (111 months) of disappearance of anti-TPO and median time (41 months) of disappearance of anti-Tg in patients with tumor size <2 cm (p=0.0175). We concluded that patients with differentiated thyroid carcinoma and pre-surgical elevated titers of both Tg and anti-TPO tend to become earlier anti-Tg seronegative. Although tumor size and age may influence the pattern of thyroid autoantibody reduction, the exact reasons for the different rhythm of autoantibodies decrease must further be evaluated.
Asunto(s)
Autoanticuerpos/sangre , Yoduro Peroxidasa/inmunología , Radioisótopos de Yodo/uso terapéutico , Tiroglobulina/inmunología , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Adolescente , Adulto , Anciano , Autoanticuerpos/biosíntesis , Niño , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia , Neoplasias de la Tiroides/inmunología , Neoplasias de la Tiroides/mortalidad , Neoplasias de la Tiroides/patologíaRESUMEN
Estrogens play a significant role in bone physiology. Their action is mainly exerted through their receptors. Estrogen receptor alpha (ERalpha) plays a major role in bone homeostasis and there is evidence suggesting that estrogen receptor beta (ERbeta) has also an effect on BMD. We investigated the possible effect of two ERbeta gene polymorphisms on spinal bone mineral density (BMD) and metabolic bone markers in Greek women. Spine BMD as well as biochemical bone markers were measured in 147 healthy peri- and post-menopausal women [mean age (S.D.) 54 (7.9) years]. Genotyping was performed for two restriction fragment length polymorphisms (RFLPs) of ERbeta gene, RsaI in exon 5 and AluI in exon 8. For each polymorphism studied the cohort was divided into two groups: the "wild-type" group (RR and AA, respectively) and the "carrier" group including subjects with at least one allele with the restriction site (Rr&rr and Aa&aa, respectively). The distribution of RsaI genotypes was RR: 91.2% (n = 134), Rr: 8.2% (n = 12), and rr: 0.6% (n = 1) and of AluI genotypes AA: 36.7% (n = 54), Aa: 57.2% (n = 84), and aa: 6.1% (n = 9). No linkage disequilibrium was found between the two polymorphic sites studied. Spine BMD did not differ significantly in the two groups of either polymorphism, after adjusting for age, weight, height, and years since menopause [mean BMD (S.D.) for RR 0.841 (0.17) g/cm(2) versus Rr&rr 0.798 (0.13) g/cm(2), p = 0.25, and mean BMD (S.D.) for AA 0.828 (0.16)g/cm(2) versus Aa&aa 0.848 (0.17) g/cm(2), p = 0.32]. No significant differences were noted in metabolic bone markers except for a marginal difference of RR versus Rr/rr in urinary hydroxyproline/creatinine ratio [median (IQR) 3.88 (6.04) micromol/mmol in RR versus 8.2 (4.32) micromol/mmol in Rr/rr, p = 0.05]. Furthermore, no interaction between the two polymorphisms on BMD was found. In conclusion, in a Greek female post-menopausal population, the two ERbeta gene polymorphisms were not associated with BMD, or metabolic bone markers.
Asunto(s)
Densidad Ósea/genética , Receptor beta de Estrógeno/genética , Osteoporosis Posmenopáusica/genética , Polimorfismo de Nucleótido Simple/genética , Absorciometría de Fotón , Biomarcadores/sangre , Biomarcadores/orina , Densidad Ósea/fisiología , Distribución de Chi-Cuadrado , Receptor beta de Estrógeno/fisiología , Femenino , Genotipo , Grecia , Humanos , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple/fisiología , Columna Vertebral/fisiología , Estadísticas no ParamétricasRESUMEN
Fine needle aspiration biopsy (FNAB)-based cytology is an accurate preoperative diagnostic method for the evaluation of thyroid nodules. Despite its high specificity and sensitivity, the results are non-diagnostic in a significant number of cases, commonly due to inadequacy of the samples or the presence of undetermined cellular morphology. Overlap-ping cytologic features among follicular-derived lesions are the most common causes of cyto-histopathologic discordances. The management of thyroid nodules with a non-diagnostic FNAB remains controversial. The significant probability of malignancy imposes either the repeat of the procedure or direct surgery. Recent studies have demonstrated the important role of molecular-based techniques such as RT-PCR in the diagnosis of thyroid lesions. Follicular cells obtained from the remaining material within the needle can be used for RNA extraction and then for RT-PCR amplification of specific mRNAs that are expressed in benign or malignant thyroid nodules. Furthermore, FNAB-RT-PCR in combination with molecular scanning techniques or direct sequencing provides a valuable screening tool for mutations. The present review highlights the applications of FNAB-RT-PCR method in the identification of new diagnostic molecular markers. The parallel molecular and cytological analysis of FNABs may contribute to a more accurate diagnosis and, thus, to a more specific clinical management of thyroid nodules.
Asunto(s)
Biopsia con Aguja Fina/métodos , Cuidados Preoperatorios , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Nódulo Tiroideo/diagnóstico , Nódulo Tiroideo/genética , Humanos , Sensibilidad y Especificidad , Análisis de Secuencia de ADN , Nódulo Tiroideo/cirugía , TiroidectomíaRESUMEN
Fine-needle aspiration biopsy (FNAB) of the thyroid gland is the most cost-effective examination in the evaluation of thyroid nodules. The aim of this study was to present our experience from all patients who underwent thyroid FNA in the University Hospital of Ioannina, Greece, in the period 1993-2003, and its value in the diagnostic management of patients with thyroid nodules. FNA was performed in 900 patients of whom 753 were females and 147 males. The cases were classified according to diagnosis into five groups: benign/negative 628, primary carcinoma 28, metastatic carcinoma 5, suspicious/indeterminate 60 and non-diagnostic 179. Cytological findings were compared with histopathological findings and the statistical analysis in our data yielded the following results: sensitivity 92.1%, specificity 93.2%. These results are in accordance with the already published data in the international literature. In cases of differential diagnosis between adenomatoid hyperplasia and follicular neoplasia, four cases were diagnosed as hot nodules. In the benign group, three cases were diagnosed as nodular hyperplasia with cystic degeneration on FNA, but, after surgical treatment, histologically were diagnosed as papillary carcinomas. In the group of suspicious/indeterminate, two cases were diagnosed as suspicious for follicular neoplasia on FNA and, after surgical treatment, were diagnosed histopathologically as medullary carcinomas. In conclusion, we suggest that routine measurement of serum calcitonin is useful and mandatory in the detection of medullary carcinoma among patients with nodular thyroid diseases. Taking into consideration the clinical data can minimize false-positive and false-negative rates. We conclude that FNA is an effective screening test in the evaluation of the necessity for surgical treatment in patients with thyroid nodules.
Asunto(s)
Biopsia con Aguja Fina/métodos , Nódulo Tiroideo/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Diagnóstico Diferencial , Femenino , Grecia , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Neoplasias de la Tiroides/patología , Neoplasias de la Tiroides/cirugía , Nódulo Tiroideo/clasificación , Nódulo Tiroideo/cirugía , Resultado del TratamientoRESUMEN
Several studies have addressed the effect of the Spl polymorphism of the collagen Ialpha 1 (COLIA1) gene on the prevalence of fractures. The results are not in full agreement on whether this polymorphism is associated with fracture risk. To clarify this uncertainty, we performed a meta-analysis including 13 eligible studies with 3641 subjects. The COLIA1 Spl polymorphism showed a dose-response relationship with the prevalence of fractures. The risk was 1.25-fold (95% CI, 1.09-1.45) in Ss heterozygotes versus SS homozygotes, 1.68-fold (95% CI, 1.35-2.10) in ss homozygotes versus SS homozygotes, and 1.35 (95% CI, 1.04-1.75) for ss homozygotes versus Ss heterozygotes by random effects calculations. There was modest heterogeneity for these three effect estimates (p value for heterogeneity, 0.17, 0.16, and 0.08, respectively). The Sp1 polymorphism effects possibly were larger when the analysis was limited to studies considering only vertebral fractures (pooled risk ratios [RR], 1.30, 2.07, and 1.46, respectively). Conversely, the Spl polymorphism effects tended to be smaller in studies with mean patient age > or = 65 years than in studies with younger patients on average, but the differences were not formally significant. We estimated the total average attributable fraction (AF) of fractures due to the s allele in European/U.S. populations as 9.4%. The meta-analysis suggests an important role for the Spl polymorphism in the regulation of fracture risk; however, potential heterogeneity across ethnic groups, age groups, and skeletal sites may be important to clarify in future studies. Very large studies or meta-analyses are required to document subtle genetic differences in fracture risk.
Asunto(s)
Colágeno Tipo I , Colágeno/genética , Fracturas Óseas/epidemiología , Polimorfismo Genético , Factor de Transcripción Sp1/metabolismo , Sitios de Unión , Cadena alfa 1 del Colágeno Tipo I , Fracturas Óseas/genética , Humanos , Prevalencia , Factores de RiesgoRESUMEN
The physiological role of GH in the adult skeleton is unknown. In this study, 12 adults (10 males and 2 females) with isolated GH deficiency were treated with GH as a single daily sc injection (0.125 IU/kg.week for the first 4 weeks and subsequently at 0.25 IU/kg.week) for 1 yr in a double blind, placebo-controlled manner. Bone mineral density of the spine (T12-L3) was measured by quantitative computed tomography, and bone mineral content (BMC) of the forearm by single photon absorptiometry at entry into the study and subsequently at 6 monthly intervals. All baseline bone mineral measurements were reduced compared with those in an age- and sex-matched control population. In the treatment cohort, quantitative computed tomography spinal trabecular bone mineral density increased by 7.8 g/L after 6 months of GH replacement (mean +/- SEM, 151.7 +/- 6.0 vs. 159.5 +/- 5.9 g/L; n = 11; P < 0.01), and this increment was maintained at 1 yr (160.7 +/- 6.3 g/L). Proximal forearm (cortical) BMC showed no change after 6 months of GH replacement, but there was a significant increase of 0.06 g/cm after 12 months of GH replacement (from 1.38 +/- 0.04 to 1.44 +/- 0.04 g/cm; n = 12; P < 0.05). Distal forearm (cortical and trabecular) BMC also increased significantly during the study period from 1.46 +/- 0.04 g/cm to 1.52 +/- 0.05 g/cm; n = 12, P < 0.05. No significant changes occurred in bone mineral measurements during 6 months of placebo therapy. Midthigh muscle and fat cross-sectional area increased and decreased, respectively, during the active treatment phase. These results demonstrate that GH plays an important role in maintaining the integrity of the adult skeleton.
Asunto(s)
Densidad Ósea/efectos de los fármacos , Hormona del Crecimiento/deficiencia , Hormona del Crecimiento/uso terapéutico , Tejido Adiposo/efectos de los fármacos , Adolescente , Adulto , Método Doble Ciego , Femenino , Humanos , Masculino , Músculos/efectos de los fármacos , Músculos/patología , Placebos , Proteínas Recombinantes , Columna Vertebral/diagnóstico por imagen , Columna Vertebral/efectos de los fármacos , Muslo , Factores de Tiempo , Tomografía Computarizada por Rayos XRESUMEN
Testicular function was studied in three groups of patients previously treated for malignant disease, and a control group of adult males. The adult patients in groups one and two underwent unilateral orchidectomy for a testicular tumour but only in group two was this followed by post-operative high-dose irradiation (30 Gy) to the remaining testis. Four of the five boys in group three had a unilateral orchidectomy between the ages of 1 and 4 years and all five received a similar dose of irradiation (27.5-30 Gy) to the scrotum as in group two. The five subjects in group three were studied between the ages of 12 and 34 years. In group one the median basal testosterone level (16.0 nmol/l) was normal and the basal gonadotrophin levels mildly but significantly increased, reflecting a resetting of the pituitary-testicular axis following unilateral orchidectomy. In group two the median basal testosterone level (12.5 nmol/l) was significantly lower and the median basal FSH and LH levels were significantly higher than the respective values in group one, indicating that irradiation to the testis in adult life may damage both the germinal epithelium and the Leydig cells. All five males in group three showed grossly increased FSH and LH levels, with a median basal testosterone level (less than 2.5 nmol/l) significantly lower than groups one and two. None of the five showed a testosterone response to a stimulation test with human chorionic gonadotrophin or underwent puberty spontaneously.(ABSTRACT TRUNCATED AT 250 WORDS)
Asunto(s)
Células Intersticiales del Testículo/efectos de la radiación , Traumatismos por Radiación/etiología , Radioterapia de Alta Energía/efectos adversos , Adolescente , Adulto , Factores de Edad , Hormona Folículo Estimulante/sangre , Humanos , Hormona Luteinizante/sangre , Masculino , Persona de Mediana Edad , Pubertad , Testosterona/sangreRESUMEN
The degree of stability in vitro of bioactive and immunoreactive LH in human blood, plasma and serum was examined. Bioactivity and immunoreactivity of LH were assayed by the dispersed mouse Leydig cell assay and by standard radioimmunoassay respectively, using the same reference preparation (first international reference preparation for human pituitary LH 68/40 for immunoassay). Bioactive and immunoreactive LH were stable in blood and plasma at 22 degrees C for up to 4 and 24 h respectively, and in blood at 4 degrees C for up to 24 h. There was no loss of biological or immunological LH activity in plasma which had been either snap-frozen and stored at -70 degrees C, allowed to freeze at -20 degrees C and stored at that temperature or kept at 4 degrees C for 24 h and then stored at -70 degrees C. Likewise, the levels of LH in plasma and serum which had been stored at either -20 or -70 degrees C and then thawed and refrozen up to four times remained unchanged. In addition, the biological and immunological activity of LH was not affected after vortexing samples of plasma or serum for up to 60 s. Bioactive LH was also stable in plasma samples after prolonged storage (up to 9 months) at either -70 or -20 degrees C. We conclude that LH bioactivity and immunoreactivity are stable in blood and plasma following a variety of treatments commonly experienced during normal handling of a blood sample after venepuncture.
Asunto(s)
Hormona Luteinizante/sangre , Bioensayo , Conservación de la Sangre , Recolección de Muestras de Sangre/normas , Estabilidad de Medicamentos , Femenino , Congelación , Humanos , Hormona Luteinizante/inmunología , Masculino , Radioinmunoensayo , Factores de TiempoRESUMEN
Recent evidence has emphasized the importance of apoptosis in the maintenance of tissue homeostasis and the pathogenesis of malignant and immune diseases. Autoimmune thyroid diseases such as Hashimoto's thyroiditis and Graves' disease, as well as other autoimmune endocrine diseases, have been associated with dysregulation of apoptotic signaling pathways. In particular, dysfunction of the Fas apoptotic pathway or production of soluble factors including soluble Fas and soluble Fas ligand may be involved in the pathogenesis of these disorders. On the other hand, malignant thyroid cells may avoid Fas-mediated suicide possibly by expression of inhibitors of apoptosis and evade the immune system by inducing apoptosis on infiltrating lymphocytes. The delicate balance between cell proliferation and cell death through the Fas pathway may also play an important role in the control of thyroid cell mass and goitrogenesis. This review analyzes the current evidence on the role of Fas-mediated apoptosis in the pathogenesis of thyroid diseases including Hashimoto's thyroiditis, Graves' disease, thyroid cancer and goiter. However, the exact mechanisms involved in the regulation of apoptosis in thyroid disease remain unclear. Further investigation is needed.
Asunto(s)
Apoptosis/fisiología , Enfermedades de la Tiroides/patología , Receptor fas/fisiología , Animales , HumanosRESUMEN
Polycystic ovary syndrome (PCOS) is a common endocrine disorder in women of reproductive age. The disorder is characterized by clinical features of hyperandrogenism, menstrual irregularities and often central obesity and hyperinsulinaemia. PCOS may increase the risk for infertility, type 2 diabetes mellitus, dyslipidaemia, cardiovascular disease and endometrial cancer, emphasizing the need for early diagnosis of the syndrome. The genetic basis of PCOS is unknown. There is a strong familial component but the mode of inheritance is uncertain and several candidate genes have been proposed to contribute to susceptibility. Not only genes involved in steroid hormone biosynthesis have been studied but also genes associated with the regulation of insulin secretion and action since hyperinsulinaemia is a characteristic of PCOS. So far there is evidence that INS VNTR (insulin variable number of tandem repeats) or CYP11alpha (cholesterol side chain cleavage) genes are associated with this syndrome. PCOS appears, however, to be an oligogenic disorder and more studies are necessary to define the genetic basis.
Asunto(s)
Síndrome del Ovario Poliquístico/genética , Enzima de Desdoblamiento de la Cadena Lateral del Colesterol/genética , Femenino , Folistatina/genética , Humanos , Insulina/genética , Hormona Luteinizante de Subunidad beta/genética , Síndrome del Ovario Poliquístico/metabolismo , Receptor de Insulina/genética , Receptores Androgénicos/genética , Esteroide 17-alfa-Hidroxilasa/genéticaRESUMEN
OBJECTIVE: The relative expression of the apoptotic protein Fas and the anti-apoptotic protein Bcl-2 were investigated in thyrocytes from patients with non-toxic nodular goiter (NTG, n=20) and Hashimoto's thyroiditis (HT, n=5), who underwent fine-needle aspiration biopsy for diagnostic reasons. On the basis of the clinical and cytological findings, the patients with NTG were sub-classified into the group of those with colloid nodules (n=9), degenerative nodules (n=6) and adenomatous nodules (n=5). METHODS: Fine-needle biopsy aspirates were examined by immunocytochemistry for Fas and Bcl-2 expression, using specific monoclonal antibodies. For the evaluation of Fas and Bcl-2 immuno-reactivity, an expression index, based on the number of cells with positive staining, was used: grade 1 included samples with positive staining in <20% of cells; grade 2 included samples with 20-50% positive cells; and grade 3 included samples with >50% positive cells. RESULTS: Fas protein expression was generally low (grade 1) in patients with nodular goiter, in contrast to patients with HT, in whom high expression was detected (grade 3). Only in aspirates from degenerative nodules (four out of six), and in which lymphocytes were also present, was Fas expressed at an intermediate level (grade 2). On the other hand, Bcl-2 protein was differentially expressed among the nodule subtypes. It was low in colloid and degenerative nodules (grade 1) but high in adenomatous ones (grades 2 and 3). Bcl-2 expression was also low in patients with HT (grade 1). CONCLUSION: It is concluded that in comparison to HT, where there is up-regulation of Fas and down-regulation of Bcl-2 protein, Fas expression is low in human goiter, indicating low apoptotic activity. The regulation of Bcl-2 protein differs between adenomatous and colloid nodules, suggesting that this protein may play a role in the differentiation of thyroid nodules.
Asunto(s)
Bocio Nodular/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Glándula Tiroides/metabolismo , Receptor fas/metabolismo , Adulto , Anciano , Femenino , Bocio Nodular/patología , Humanos , Masculino , Persona de Mediana Edad , Glándula Tiroides/patología , Tiroiditis Autoinmune/metabolismo , Tiroiditis Autoinmune/patologíaRESUMEN
OBJECTIVE: Variations in thyroid function are known to be associated with changes in adrenocortical activity. Previous studies in animals have suggested that long-standing hyperthyroidism may be associated with diminished adrenal functional reserve despite a continuing hyperactivity of the hypothalamic-pituitary-adrenal (HPA) axis. In humans, there has been no direct assessment of adrenal secretory reserve in clinical thyrotoxicosis. This study aimed to assess adrenocortical reserve in response to low-dose ACTH, following dexamethasone suppression, in patients with severe thyrotoxicosis. DESIGN AND METHODS: Ten patients (four men and six women, 30-45 years) with severe long-standing thyrotoxicosis due to Graves' disease (n=6) or toxic nodular goitre (n=4) were studied at diagnosis and again when in a stable euthyroid state following drug therapy for 8-12 months. All patients underwent ACTH stimulation tests at 0800h with ACTH(1-24) (Cortrosyn; 0.1microg/kg body weight, i.v.) following overnight suppression of the HPA axis with dexamethasone (1mg per os at 2300h). Serum cortisol was assayed at -15, 0, 15, 30, 60 and 90min after the administration of ACTH. RESULTS: The mean (+/-s.d.) peak and delta cortisol responses to ACTH (634.5+/-164nmol/l and 618+/- 196nmol/l respectively), as well as the net area under the response curve (36769+/-12188nmol/lx min) in the hyperthyroid patients were significantly lower compared with the values when the same patients were euthyroid (911+/-157nmol/l, 905+/-160nmol/l and 57652+/-10128nmol/lxmin respectively; P<0.005). Subnormal peak cortisol responses (<500nmol/l) were observed in two severely toxic patients. The findings were independent of the cause of thyrotoxicosis. CONCLUSION: In patients with severe thyrotoxicosis, cortisol secretion in response to low-dose ACTH stimulation, following dexamethasone suppression, is lower in the hyperthyroid than in the euthyroid state. It appears that thyrotoxicosis is associated with subtle impairment of adrenocortical reserve.
Asunto(s)
Corteza Suprarrenal/metabolismo , Hormona Adrenocorticotrópica/metabolismo , Hidrocortisona/sangre , Tirotoxicosis/sangre , Hormona Adrenocorticotrópica/administración & dosificación , Adulto , Anticuerpos/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Glándula Tiroides/inmunología , Hormonas Tiroideas/sangre , Tirotoxicosis/etiología , Tirotropina/sangre , Factores de TiempoRESUMEN
OBJECTIVE: The significance of dyslipidemia in subclinical hypothyroidism (SH) and the effect of thyroid substitution on lipids remain controversial. The present study aimed to assess the association of SH with lipid abnormalities and to quantify the effect of L-thyroxine therapy on serum lipid profiles. DESIGN: Serum lipid parameters of 66 patients with SH and 75 age- and sex-matched euthyroid controls were evaluated in a cross-sectional study. RESULTS: Patients with SH had higher total cholesterol (TC) (222+/-45 (s.d.) vs 190+/- 32 mg/dl), low-density lipoprotein cholesterol (LDL-C) (139+/-28 vs 118+/-39 mg/dl), apolipoprotein B (149+/-21 vs 139+/-18 mg/dl) and lipoprotein (a) (Lp(a)) (median 12.5 (0.8-101) mg/dl vs 7 (0.8-44) mg/dl) levels compared with euthyroid controls (P<0.05 for all comparisons). In a follow-up study including 37 patients with SH, all measurements were repeated after restoration of a euthyroid state with incremental doses of l-thyroxine. No significant changes in serum lipid profiles were observed except for a decrease in high-density lipoprotein cholesterol (59+/-15 to 55+/-14 mg/dl, P<0.05). However, patients with high pre-treatment TC (> or =240 mg/dl) showed a significant reduction in both TC (278+/-28 vs 257+/-36 mg/dl, P<0.05) and LDL-C (192+/-23 vs 173+/-28 mg/dl, P<0.01) levels. Similar but more pronounced changes were observed in a subgroup of patients with pre-treatment levels of TSH > or =10 microU/ml. Thyroid autoimmunity had no effect on either the baseline or the post-treatment lipid profile. CONCLUSION: Although patients with subclinical hypothyroidism exhibit increased levels of the atherogenic parameters (mainly LDL-C and Lp(a)), thyroid substitution therapy does not seem to significantly improve dyslipidemia in the whole group of patients.
Asunto(s)
Hipotiroidismo/sangre , Hipotiroidismo/tratamiento farmacológico , Lípidos/sangre , Tiroxina/uso terapéutico , Adulto , Apolipoproteínas B/sangre , Colesterol/sangre , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Femenino , Humanos , Hiperlipidemias/complicaciones , Hipotiroidismo/complicaciones , Lipoproteína(a)/sangre , Masculino , Persona de Mediana Edad , Tirotropina/sangreRESUMEN
The paradox of normal or even excessive growth despite a proven lack of GH is a well-known but still unexplained phenomenon that has been described in some patients following resection of a craniopharyngioma or other suprasellar tumours. However, the consequences of GH deficiency on other metabolic aspects of GH action in this syndrome have not been adequately investigated. The aim of this study was to examine whether a dissociation might exist between the growth-promoting and metabolic effects of GH. We studied a 7.1 year old boy who, after removal of a suprasellar craniopharyngioma, developed panhypopituitarism with mild hyperprolactinaemia. Despite the presence of severe GH deficiency associated with persistently low IGF-I and IGFBP-3 levels, the patient grew spontaneously at an accelerated rate for a prepubertal boy, achieving a height velocity of 9.0 cm during the first and 8.5 cm during the second post-operative year. However, other metabolic parameters of GH activity were adversely affected by the lack of GH. The maximum tubular reabsorption rate for phosphate over glomerular filtration rate ratio (2.8) was persistently low and normalized during a 4 day course of hGH administration (4.2) together with the normalization of IGF-I (from 34 microg/l to 294 microg/l), suggesting that GH-dependent renal phosphate handling is impaired in this syndrome. In addition, bone age was delayed by 1.7 years consistently with delayed skeletal maturation, whereas skinfold thickness and the waist to hip ratio were increased in comparison with normative data, suggesting increased adipose tissue mass with central fat distribution, a phenotype characteristic of GH deficiency. In conclusion, our case study suggests that, in the "growth without GH" syndrome, the excessive growth is independent of GH and dissociated from other GH-dependent metabolic effects, which are decreased.
Asunto(s)
Hormona de Crecimiento Humana/deficiencia , Hormona de Crecimiento Humana/metabolismo , Hormona de Crecimiento Humana/uso terapéutico , Estatura , Desarrollo Óseo , Niño , Craneofaringioma/complicaciones , Craneofaringioma/cirugía , Tasa de Filtración Glomerular , Humanos , Hipopituitarismo/diagnóstico , Hipotálamo/fisiología , Insulina/sangre , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/biosíntesis , Factor I del Crecimiento Similar a la Insulina/biosíntesis , Masculino , Fenotipo , Hipófisis/fisiología , Prolactina/biosíntesis , Factores de TiempoRESUMEN
In the present study, the changes in circulating IGF-1 and its binding protein IGFBP-3 were determined in adult patients with active inflammatory bowel disease (IBD) in order to assess the effect of this inflammatory condition on the IGF system. IGF-1 and IGFBP-3, as well as interleukin-6 (IL-6) were measured in serum obtained from 22 consecutive newly diagnosed patients (mean age 41.3 years) with active IBD, including 10 patients with Crohn's disease (CD), and 12 with ulcerative colitis (UC). For comparison the same parameters were determined in 30 healthy volunteers matched for age, sex and Body Mass Index (BMI). Serum IGF-1 and IGFBP-3 levels were similar in the two subgroups of patients and the values from all patients were combined for comparison with those from the control group. The mean (+/- SD) serum IGF-1 concentration (178 +/- 91 ng/ml) in the patients with IBD was lower compared with that in the controls (227 +/- 79 ng/ml, P<0.035). Similarly, the mean IGFBP-3 concentration in the patients was lower than in the controls (1.6 +/- 0.6 ng/ml vs 3.2 +/- 0.7 ng/ml respectively, P<0.001), Serum IL-6 levels were higher in the patients compared with the controls (5.5 +/- 4.2 vs 0.65 +/- 0.11 pg/ml, P<0.0001). The reduced IGF-1 and IGFBP-3 levels in patients with active IBD suggest that this systemic inflammatory condition is associated with a degree of acquired GH resistance, possibly induced by inflammatory cytokines.
Asunto(s)
Enfermedades Inflamatorias del Intestino/sangre , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Adulto , Estudios de Casos y Controles , Colitis Ulcerosa/sangre , Enfermedad de Crohn/sangre , Femenino , Humanos , Mediadores de Inflamación/sangre , Interleucina-6/sangre , Masculino , Persona de Mediana EdadRESUMEN
The stimulated and spontaneous growth hormone (GH) secretion and the response to GH action were assessed in growth-retarded children with juvenile chronic arthritis (JCA), in order to determine the underlying mechanisms of growth retardation in such children. Six children (4 boys and 2 girls aged 10.7-13.8 years) with active JCA of systemic onset were included in the study which involved: (1) anthropometric measurements; (2) assessment of GH responses to insulin-induced hypoglycaemia and clonidine stimulation; (3) assessment of the nocturnal pulsatile GH secretion by measuring GH in blood samples obtained every 20 min from 20.00 to 08.00 h; and (4) the IGF-I generation test. As a control, the latter test was also performed in eight aged-matched children with physiological delay in puberty. Biosynthetic hGH (0.1 IU/kg BW) was administered s. c. for 4 days and blood samples were taken at baseline and the morning after the last GH injection for measurement of IGF-I and IGFBP-3. All six children with JCA were prepubertal and their growth velocity was <3 cm/year. The GH responses to both stimulation tests were normal (peak GH >20 mU/l). Analysis of the pulsatile GH secretion during the night revealed three-to-four GH pulses of normal amplitude (>20 mU/l). IGF-I (26.7+/-4.6 nmol/l, mean+/-SD) and IGFBP-3 (2.1+/-0.2 mg/l) levels were lower in the patients compared with the controls (43.0+/-3.7 nmol/l and 2.8+/-0.2 mg/l, respectively, P<0.01). Following stimulation with exogenous hGH, there was a significant increase in IGF-I and IGFBP-3 levels in the control group (85 and 73%, respectively), but only a small increase in the patients (31 and 14%). It appears that stimulated and spontaneous GH secretion is normal in children with active systemic JCA, but the response to endogenous and exogenous GH with regard to IGF-I and IGFBP-3 production is impaired, indicating a degree of GH insensitivity in such children.