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1.
Eur J Endocrinol ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38771697

RESUMO

OBJECTIVE: To compare the response to first-line medical treatment in treatment-naive acromegaly patients with pure growth hormone (GH)-secreting pituitary adenoma (GH-PA) and those with GH and prolactin co-secreting PA (GH&PRL-PA). DESIGN: Retrospective multicentric study of acromegaly patients followed from 2003 to 2023 in 33 tertiary Spanish hospitals with at least six months of first-line medical treatment. METHODS: Baseline characteristics, first-line medical treatment strategies, and outcomes were analysed. We employed a multiple logistic regression full model to estimate the impact of some baseline characteristics on disease control after each treatment modality. RESULTS: Of the 144 patients included, 72.9% had a GH-PA, and 27.1% had a GH&PRL-PA. Patients with GH&PRL-PA were younger (43.9 ± 15.0 vs. 51.9 ± 12.7 years; p < 0.01) and harboring more frequently macroadenomas (89.7% vs. 72.1%, p = 0.03). First generation somatostatin receptor ligand (fgSRL) as monotherapy was given to 106 (73.6%) and a combination treatment with fgSRL and cabergoline in the remaining 38 (26.4%). Patients with GH&PRL-PA received more frequently a combination therapy (56.4% vs. 15.2%; p < 0.01). After 6 months of treatment, in the group of patients under fgSRL as monotherapy, those patients with GH&PRL-PA had worse control compared to GH-PAs (29.4% vs. 55.1%, p = 0.04). However, these differences in the rate of disease control between both groups disappeared when both received combination treatment with fgSRL and cabergoline. CONCLUSION: In GH&PRL-PA the biochemical control achieved with fgSRL as monotherapy is substantially worse than in patients harboring GH-PA, supporting the inclusion of cabergoline as first line medical treatment in combination with fgSRLs in these subgroups of patients.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38436926

RESUMO

PURPOSE: To evaluate differences in clinical presentation and in surgical outcomes between growth hormone-secreting pituitary adenomas (GH-PAs) and GH and prolactin co-secreting pituitary adenomas (GH&PRL-PAs). METHODS: Multicenter retrospective study of 604 patients with acromegaly submitted to pituitary surgery. Patients were classified into two groups according to serum PRL levels at diagnosis and immunohistochemistry (IHC) for PRL: a) GH&PRL-PAs when PRL levels were above the upper limit of normal and IHC for GH and PRL was positive or PRL levels were >100ng/and PRL IHC was not available (n=130) and b) GH-PAs who did not meet the previously mentioned criteria (n=474). RESULTS: GH&PRL-PAs represented 21.5% (n=130) of patients with acromegaly. The mean age at diagnosis was lower in GH&PRL-PAs than in GH-PAs (P<0.001). GH&PRL-PAs were more frequently macroadenomas (90.6% vs. 77.4%, P=0.001) and tended to be more invasive (33.6% vs. 24.7%, P=0.057) than GH-PAs. Furthermore, they had presurgical hypopituitarism more frequently (OR 2.8, 95% CI 1.83-4.38). IGF-1 upper limit of normality (ULN) levels at diagnosis were lower in patients with GH&PRL-PAs (median 2.4 [IQR 1.73-3.29] vs. 2.7 [IQR 1.91-3.67], P=0.023). There were no differences in the immediate (41.1% vs 43.3%, P=0.659) or long-term post-surgical acromegaly biochemical cure rate (53.5% vs. 53.1%, P=0.936) between groups. However, there was a higher incidence of permanent arginine-vasopressin deficiency (AVP-D) (7.3% vs. 2.4%, P=0.011) in GH&PRL-PAs patients. CONCLUSIONS: GH&PRL-PAs are responsible for 20% of acromegaly cases. These tumors are more invasive, larger and cause hypopituitarism more frequently than GH-PAs and are diagnosed at an earlier age. The biochemical cure rate is similar between both groups, but patients with GH&PRL-PAs tend to develop permanent postsurgical AVP-D more frequently.

3.
Front Endocrinol (Lausanne) ; 14: 1269787, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38027102

RESUMO

Introduction: We previously described that a short version of the acute octreotide test (sAOT) can predict the response to first-generation somatostatin receptor ligands (SRLs) in patients with acromegaly. We have prospectively reassessed the sAOT in patients from the ACROFAST study using current ultra-sensitive GH assays. We also studied the correlation of sAOT with tumor expression of E-cadherin and somatostatin receptor 2 (SSTR2) . Methods: A total of 47 patients treated with SRLs for 6 months were evaluated with the sAOT at diagnosis and correlated with SRLs' response. Those patients whose IGF1 decreased to <3SDS from normal value were considered responders and those whose IGF1 was ≥3SDS, were considered non-responders. The 2 hours GH value (GH2h) after s.c. administration of 100 mcg of octreotide was used to define predictive cutoffs. E-cadherin and SSTR2 immunostaining in somatotropinoma tissue were investigated in 24/47 and 18/47 patients, respectively. Results: In all, 30 patients were responders and 17 were non-responders. GH2h was 0.68 (0.25-1.98) ng/mL in responders vs 2.35 (1.59-9.37) ng/mL in non-responders (p<0.001). GH2h = 1.4ng/mL showed the highest ability to identify responders (accuracy of 81%, sensitivity of 73.3%, and specificity of 94.1%). GH2h = 4.3ng/mL was the best cutoff for non-response prediction (accuracy of 74%, sensitivity of 35.3%, and specificity of 96.7%). Patients with E-cadherin-positive tumors showed a lower GH2h than those with E-cadherin-negative tumors [0.9 (0.3-2.1) vs 3.3 (1.5-12.1) ng/mL; p<0.01], and patients with positive E-cadherin presented a higher score of SSTR2 (7.5 ± 4.2 vs 3.3 ± 2.1; p=0.01). Conclusion: The sAOT is a good predictor tool for assessing response to SRLs and correlates with tumor E-cadherin and SSTR2 expression. Thus, it can be useful in clinical practice for therapeutic decision-making in patients with acromegaly.


Assuntos
Acromegalia , Adenoma , Neoplasias Hipofisárias , Humanos , Octreotida/uso terapêutico , Acromegalia/diagnóstico , Acromegalia/tratamento farmacológico , Acromegalia/metabolismo , Somatostatina/uso terapêutico , Resultado do Tratamento , Neoplasias Hipofisárias/metabolismo , Adenoma/tratamento farmacológico , Caderinas
4.
Sci Rep ; 12(1): 8979, 2022 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-35643771

RESUMO

Predicting which acromegaly patients could benefit from somatostatin receptor ligands (SRL) is a must for personalized medicine. Although many biomarkers linked to SRL response have been identified, there is no consensus criterion on how to assign this pharmacologic treatment according to biomarker levels. Our aim is to provide better predictive tools for an accurate acromegaly patient stratification regarding the ability to respond to SRL. We took advantage of a multicenter study of 71 acromegaly patients and we used advanced mathematical modelling to predict SRL response combining molecular and clinical information. Different models of patient stratification were obtained, with a much higher accuracy when the studied cohort is fragmented according to relevant clinical characteristics. Considering all the models, a patient stratification based on the extrasellar growth of the tumor, sex, age and the expression of E-cadherin, GHRL, IN1-GHRL, DRD2, SSTR5 and PEBP1 is proposed, with accuracies that stand between 71 to 95%. In conclusion, the use of data mining could be very useful for implementation of personalized medicine in acromegaly through an interdisciplinary work between computer science, mathematics, biology and medicine. This new methodology opens a door to more precise and personalized medicine for acromegaly patients.


Assuntos
Acromegalia , Neoplasias , Acromegalia/tratamento farmacológico , Acromegalia/terapia , Biomarcadores , Análise de Dados , Mineração de Dados , Humanos , Neoplasias/terapia , Medicina de Precisão
5.
Clin Endocrinol (Oxf) ; 94(5): 811-819, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-32978826

RESUMO

OBJECTIVE: Large somatotrophic adenomas depict poor response to somatostatin receptor ligands (SRLs). Debulking has shown to enhance SRLs effect in some but not all cases and tumour volume reduction has been proposed as the main predictor of response. No biological studies have been performed so far in this matter. We aimed to identify molecular markers of response to SRLs after surgical debulking in GH-secreting adenomas. DESIGN: We performed a multicenter retrospective study. PATIENTS: 24 patients bearing large GH-producing tumours. MEASUREMENTS: Clinical data and SRLs response both before and after surgical debulking were collected, and 21 molecular biomarkers of SRLs response were studied in tumour samples by gene expression. RESULTS: From the 21 molecular markers studied, only two of them predicted enhanced SRLs response after surgery. Tumours with improved response to SRLs after surgical debulking showed lower levels of Ki-67 (MKI67, FC = 0.17 and P = .008) and higher levels of RAR-related orphan receptor C (RORC) (FC = 3.1 and P Ë‚ .001). When a cut-off of no detectable expression was used for Ki-67, the model provided a sensitivity of 100% and a specificity of 52.6% with an area under the curve of 65.8%. Using a cut-off of 2 units of relative expression of RORC, the prediction model showed 100% of sensitivity and specificity. CONCLUSIONS: High levels of RORC and low levels of Ki-67 identify improved SRLs response after surgical debulking in large somatotropic adenomas. To determine their expression would facilitate medical treatment decision-making after surgery.


Assuntos
Acromegalia , Adenoma , Neoplasias Hipofisárias , Adenoma/genética , Adenoma/cirurgia , Procedimentos Cirúrgicos de Citorredução , Humanos , Antígeno Ki-67/genética , Ligantes , Receptores de Somatostatina/genética , Estudos Retrospectivos , Somatostatina
6.
J Endocr Soc ; 4(12): bvaa149, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33173841

RESUMO

AIM: To examine the impact of the lockdown caused by the COVID-19 pandemic on both the glycemic control and the daily habits of a group of patients with type 1 diabetes mellitus (T1DM) using flash continuous glucose monitoring devices (flash CGMs). METHODS: Retrospective analysis based on all the information gathered in virtual consultations from a cohort of 50 adult patients with T1DM with follow-up at our site. We compared their CGM metrics during lockdown with their own previous data before the pandemic occurred, as well as the potential psychological and therapeutic changes. RESULTS: We observed a reduction of average glucose values: 160.26 ± 22.55 mg/dL vs 150 ± 20.96 mg/dL, P = .0009; estimated glycosylated hemoglobin: 7.21 ± 0.78% vs 6.83 ± 0.71%, P = .0005; glucose management indicator 7.15 ± 0.57% vs 6.88 ± 0.49%; P = .0003, and glycemic variability: 40.74 ± 6.66 vs 36.43 ± 6.09 P < .0001. Time in range showed an improvement: 57.46 ± 11.85% vs a 65.76 ± 12.09%, P < .0001, without an increase in percentage of time in hypoglycemia. CONCLUSIONS: COVID-19 lockdown was associated with an improvement in glycemic control in patients with T1DM using CGMs.

7.
Biophys J ; 114(6): 1285-1294, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29590586

RESUMO

Human color vision is mediated by the red, green, and blue cone visual pigments. Cone opsins are G-protein-coupled receptors consisting of an opsin apoprotein covalently linked to the 11-cis-retinal chromophore. All visual pigments share a common evolutionary origin, and red and green cone opsins exhibit a higher homology, whereas blue cone opsin shows more resemblance to the dim light receptor rhodopsin. Here we show that chromophore regeneration in photoactivated blue cone opsin exhibits intermediate transient conformations and a secondary retinoid binding event with slower binding kinetics. We also detected a fine-tuning of the conformational change in the photoactivated blue cone opsin binding site that alters the retinal isomer binding specificity. Furthermore, the molecular models of active and inactive blue cone opsins show specific molecular interactions in the retinal binding site that are not present in other opsins. These findings highlight the differential conformational versatility of human cone opsin pigments in the chromophore regeneration process, particularly compared to rhodopsin, and point to relevant functional, unexpected roles other than spectral tuning for the cone visual pigments.


Assuntos
Opsinas dos Cones/metabolismo , Regeneração , Retinaldeído/metabolismo , Sítios de Ligação , Opsinas dos Cones/química , Humanos , Modelos Moleculares , Ligação Proteica , Conformação Proteica , Termodinâmica
8.
Biochim Biophys Acta Mol Basis Dis ; 1863(7): 1840-1847, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28487225

RESUMO

Deuteranopia is an X-linked congenital dichromatic condition in which single point mutations in green cone opsin lead to defective non-functional cone photoreceptor cells. Green cone opsin belongs to the G protein-coupled receptor superfamily and consists of a seven transmembrane helical apoprotein covalently bound to 11-cis-retinal, by means of a protonated Schiff base linkage, in its inactive dark state. Several point mutations in green cone opsin have been reported to cause deuteranopia, but the structural details underlying the molecular mechanisms behind the malfunction of mutated opsins have not been clearly established. Here, deutan N94K and R330Q mutants were studied by introducing these substitutions into the native green cone opsin gene by site-directed mutagenesis. The mutant proteins were purified and analyzed using UV-vis spectroscopy and transducin activation assay. We find that the N94K mutant binds the retinal chromophore by means of an unprotonated Schiff base linkage in contrast to previous studies that reported no chromophore regeneration. The other mutant studied, R330Q, showed impaired functionality as measured by its reduced transducin activation ability when compared to wild-type green cone opsin. A double Cys mutant that could form a stabilizing disulfide bond was used in an attempt to address the instability of the green opsin mutants. Our results suggest the presence of key intramolecular networks which may be disrupted in deuteranopia, and these findings could help in finding therapeutic solutions for treating color blindness. Furthermore, our results can also have implications for the study of other visual pigments and other rhodopsin-like G protein-coupled receptors.


Assuntos
Defeitos da Visão Cromática , Mutação de Sentido Incorreto , Opsinas/química , Substituição de Aminoácidos , Dissulfetos/química , Dissulfetos/metabolismo , Humanos , Opsinas/genética , Opsinas/metabolismo , Estabilidade Proteica , Relação Estrutura-Atividade
9.
Sci Rep ; 6: 21570, 2016 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-26865329

RESUMO

Visual rhodopsins are membrane proteins that function as light photoreceptors in the vertebrate retina. Specific amino acids have been positively selected in visual pigments during mammal evolution, which, as products of adaptive selection, would be at the base of important functional innovations. We have analyzed the top candidates for positive selection at the specific amino acids and the corresponding reverse changes (F13M, Q225R and A346S) in order to unravel the structural and functional consequences of these important sites in rhodopsin evolution. We have constructed, expressed and immunopurified the corresponding mutated pigments and analyzed their molecular phenotypes. We find that position 13 is very important for the folding of the receptor and also for proper protein glycosylation. Position 225 appears to be important for the function of the protein affecting the G-protein activation process, and position 346 would also regulate functionality of the receptor by enhancing G-protein activation and presumably affecting protein phosphorylation by rhodopsin kinase. Our results represent a link between the evolutionary analysis, which pinpoints the specific amino acid positions in the adaptive process, and the structural and functional analysis, closer to the phenotype, making biochemical sense of specific selected genetic sequences in rhodopsin evolution.


Assuntos
Substituição de Aminoácidos , Evolução Biológica , Mamíferos/genética , Filogenia , Rodopsina/química , Adaptação Fisiológica , Alanina/química , Alanina/metabolismo , Sequência de Aminoácidos , Animais , Arginina/química , Arginina/metabolismo , Células COS , Chlorocebus aethiops , Receptor Quinase 1 Acoplada a Proteína G/genética , Receptor Quinase 1 Acoplada a Proteína G/metabolismo , Expressão Gênica , Glutamina/química , Glutamina/metabolismo , Glicosilação , Humanos , Mamíferos/classificação , Mamíferos/metabolismo , Metionina/química , Metionina/metabolismo , Modelos Moleculares , Mutação , Fenilalanina/química , Fenilalanina/metabolismo , Fosforilação , Dobramento de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Rodopsina/genética , Rodopsina/metabolismo , Seleção Genética , Serina/química , Serina/metabolismo
10.
Rev. venez. endocrinol. metab ; 7(3): 29-32, sep. 2009. ilus
Artigo em Espanhol | LILACS-Express | LILACS | ID: lil-631360

RESUMO

Objetivos: Presentar el caso de un síndrome muy raro, el Síndrome de Rothmund-Thomson, de herencia autosómica recesiva, atribuible a una mutación en el gen RECQL4 helicase, 8q24. Se caracteriza por la presencia de placas cutáneas reticuladas, atróficas, hiperpigmentadas, telangiectásicas, que a menudo se acompañan de catarata juvenil, nariz en silla de montar, defectos óseos congénitos, trastornos en el crecimiento del cabello, uñas, dientes, hipotiroidismo, talla baja e hipogonadismo. Caso clínico: Paciente femenina de 12 años que consulta por talla baja. Antecedentes personales y familiares sin importancia. La familia ha notado cambios cutáneos en la piel desde poco después del nacimiento. La niña tiene un retraso escolar importante. Al examen físico presenta talla 124 cm, peso 21 kg, ambos muy por debajo del percentil 3 para su edad y sexo. Facies de cara de pájaro, piel pálida con telangiectasias rojas en telaraña en cara, brazos y abdomen, alopecia difusa, paladar ojival, atrofia cutánea en manos y atrofia de uñas, dientes irregulares y malformados, incisivos proyectados hacia delante. Presenta bocio difuso grado Ib, telarquia estadío II de Tanner (botón mamario) y no hay pubarquia. Edad ósea de 10 años. Con los exámenes de laboratorio se diagnostica hipotiroidismo primario y se indica tratamiento con 50 μg de levotiroxina sódica. En el seguimiento a los 3 meses se nota crecimiento de 2 cms y normalización de TSH. Evaluación oftalmológica sin alteraciones. Dada la presentación clínica y la evolución de la paciente, se establece el diagnóstico de Síndrome de Rothmund Thomson. Conclusiones: El síndrome de Rothmund Thompson es una entidad clínica poco frecuente, asociada con una amplia gama de alteraciones endocrinas, por lo cual consideramos importante reportar este caso.


Objectives: To present the case of a rare syndrome, the Rothmund-Thomson syndrome, autosomal recessive, attributable to a mutation in the RECQL4 helicase gene, 8q24. It is characterized by reticulate skin plaques, atrophic, hyperpigmented, telangiectatic, often accompanied by juvenile cataracts, saddle nose, congenital bone defects, disturbances in the growth of hair, nails, teeth, hypothyroidism, short stature and hypogonadism. Clinical case: A twelve year old girl came to the clinic because of short stature. Her personal and family history was unremarkable. Her parents noticed skin changes few days after birth. She has a delay in her school performance. Physical exam: height: 124cm, weight: 21kg, both below the third percentile for her age and sex; a bird face appearance. Skin pale with red spider thelangiectasias in the face, arms and abdomen. Generalized alopecia. Arched palate. There was skin and nail atrophy in both hands, irregular and malformed teeth and incisors projected forward. Goiter grade Ib, breasts with budding tanner stage II, there was no pubic hair. Bone age of 10 years. Laboratory tests: a diagnosis of primary hypothyroidism was made. She was started on L-Thyroxine 50 micrograms daily with an increase of 2cm when she came back three months later. An ophthalmological evaluation was normal. With the above clinical findings and clinical course we conclude that she has the Rothmund-Thomson Syndrome. Conclusions: The Rothmund Thompson syndrome is a rare clinical entity associated with a wide range of endocrine disruption, so we consider it is important to report this case.

11.
Isabélica méd ; 10(2): 201-11, jul.-dic. 1985. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-31779

RESUMO

Se expone la nueva clasificación de la Diabetes Mellitus de 1.985, que incluye como nuevo tipo clínico la Diabetes Mellitus relacionada con la malnutrición. Se hace una revisión de las características de los dos Subtipos: Diabetes Pancreatica Fibrocalculosa y Diabetes Pancreatica por deficit de proteínas. Se presenta un caso de Diabetes Pancreatica Fibrocalculosa


Assuntos
Adulto , Humanos , Masculino , Ductos Pancreáticos/patologia , Diabetes Mellitus/etiologia , Distúrbios Nutricionais/complicações , Diabetes Mellitus/classificação
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