Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 30
Filtrar
1.
Dalton Trans ; 48(42): 16017-16025, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31599279

RESUMO

This paper deals with the combination of a proline-based moiety with biologically active gold centers in the oxidation states +1 and +3. In particular, six Au(i)/(iii)-proline dithiocarbamato (DTC) complexes with general formulae [Au(DTC)2] and [AuIIIX2(DTC)] (X = Cl, Br) are reported here. After the synthesis of the ligand and the complexes, all derivatives were characterized via several techniques and tested for their stability in DMSO/water media. This study was focused on the demonstration of a peculiar behavior of Au(iii)-DTC species in solution. Finally, the complexes were screened for their antiproliferative activity against 2 human cancer cell lines, namely HepG2 and HepG2/SB3, taken as models of hepatocellular carcinoma. The latter, chosen for its aggressiveness due to the upregulation of the anti-apoptotic protein SerpinB3, was selectively inhibited in terms of growth by some Au(iii)-DTC complexes.


Assuntos
Antineoplásicos/química , Carbamatos/química , Complexos de Coordenação/química , Ouro/química , Prolina/análogos & derivados , Prolina/química , Antígenos de Neoplasias/metabolismo , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Complexos de Coordenação/farmacologia , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Serpinas/metabolismo
2.
J Pept Sci ; 25(2): e3142, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30680875

RESUMO

The study of the process of HIV entry into the host cell and the creation of biomimetic nanosystems that are able to selectively bind viral particles and proteins is a high priority research area for the development of novel diagnostic tools and treatment of HIV infection. Recently, we described multilayer nanoparticles (nanotraps) with heparin surface and cationic peptides comprising the N-terminal tail (Nt) and the second extracellular loop (ECL2) of CCR5 receptor, which could bind with high affinity some inflammatory chemokines, in particular, Rantes. Because of the similarity of the binding determinants in CCR5 structure, both for chemokines and gp120 HIV protein, here we expand this approach to the study of the interactions of these biomimetic nanosystems and their components with the peptide representing the V3 loop of the activated form of gp120. According to surface plasmon resonance results, a conformational rearrangement is involved in the process of V3 and CCR5 fragments binding. As in the case of Rantes, ECL2 peptide showed much higher affinity to V3 peptide than Nt (KD  = 3.72 × 10-8 and 1.10 × 10-6  M, respectively). Heparin-covered nanoparticles bearing CCR5 peptides effectively bound V3 as well. The presence of both heparin and the peptides in the structure of the nanotraps was shown to be crucial for the interaction with the V3 loop. Thus, short cationic peptides ECL2 and Nt proved to be excellent candidates for the design of CCR5 receptor mimetics.


Assuntos
Proteína gp120 do Envelope de HIV/química , Proteína gp120 do Envelope de HIV/metabolismo , Modelos Moleculares , Receptores CCR5/química , Receptores CCR5/metabolismo , Humanos , Nanopartículas/química , Peptídeos/síntese química , Peptídeos/química
3.
Eur J Endocrinol ; 177(4): R199-R217, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28566447

RESUMO

The number of elderly people, mostly aged over 85 years (the 'oldest old'), is increasing worldwide. As a consequence, accompanying morbidity and disability have been increasing, and frailty, defined as an age-related condition of decline of physiological reserves and vulnerability, represents an emerging problem. Caring for older frail people may represent a challenge, since the elderly differ significantly from younger adults in terms of comorbidity, polypharmacy, pharmacokinetics and greater vulnerability to adverse drug reactions. Specific criteria of therapeutic appropriateness and modified goals of care are needed in such patients, also in endocrine care settings. Indeed, thyroid dysfunctions are among the most common conditions in older, multimorbid populations. The prevalence of overt and subclinical hypothyroidism is as high as 20% and thyroid hormone prescription is common in the elderly, with a trend toward levothyroxine treatment of more marginal degrees of hypothyroidism. In addition, older patients have the highest rate of overtreatment during replacement therapy and are more susceptible to developing adverse effects from thyroid hormone excess. Recently, results of a multicentric randomized controlled trial, the TRUST-IEMO collaboration trial, added further insights to the debated question of whether and when levothyroxine treatment is required and if it is beneficial in the elderly. With this in mind, we revised the relevant literature on the impact of thyroid dysfunction and replacement therapy among older people, with the aim to better define indications, benefits and risks of l-T4 replacement therapy in the frail elderly.


Assuntos
Idoso Fragilizado , Terapia de Reposição Hormonal/métodos , Hipotireoidismo/diagnóstico , Hipotireoidismo/tratamento farmacológico , Tiroxina/administração & dosagem , Idoso de 80 Anos ou mais , Humanos , Hipotireoidismo/mortalidade , Mortalidade/tendências
4.
Cytopathology ; 27(2): 115-21, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25810099

RESUMO

OBJECTIVE: In our Pathology Department, fine needle aspiration (FNA) of palpable thyroid nodules is performed by cytopathologists who ensure correct sample management and rapid on-site evaluation (ROSE). Conversely, ultrasound (US)-guided FNAs have traditionally been carried out by endocrinologists and radiologists in outside clinics, where the presence of a cytopathologist is not always feasible. To overcome this limitation, cytopathologists have started to perform US-guided FNAs themselves. This study retrospectively evaluates 1 year of this novel practice. METHODS: A total of 2225 US-guided FNAs were performed in our clinic by cytopathologists, whereas 1490 aspirates were taken by a group of non-cytopathologists. Among these, 756 FNAs were taken by a single experienced endocrinologist. The distribution of the Bethesda classification categories was evaluated in each of these groups. RESULTS: FNAs performed by cytopathologists were more often diagnostic and better prepared than those taken by non-cytopathologists, including those taken by the experienced endocrinologist (P < 0.01). The latter operator yielded a higher rate of suspicious and malignant FNAs, reflecting a more appropriate clinical triage of worrisome nodules. CONCLUSION: Although the endocrinologist's evaluation is crucial to select clinically relevant thyroid nodules, cytopathologists can reliably perform US guidance in addition to their traditional expertise in sampling, specimen preparation and ROSE.


Assuntos
Citodiagnóstico , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Médicos , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade , Manejo de Espécimes , Neoplasias da Glândula Tireoide/patologia
6.
J Endocrinol Invest ; 35(4): 407-12, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21737999

RESUMO

BACKGROUND: Obesity and insulin resistance predispose individuals to the development of both metabolic syndrome and non-toxic nodular thyroid diseases. AIM: The aim of this observational, cross-sectional study is to evaluate the relationship between metabolic syndrome and multinodular nontoxic goiter in an inpatient population from a geographic area with moderate iodine deficiency. SUBJECTS AND METHODS: We examined 1422 Caucasian euthyroid inpatients. Thyroid volume was determined by ultrasound of the neck. A fine-needle aspiration biopsy was performed to evaluate single thyroid nodules and dominant nodules ≥15 mm in euthyroid multinodular goiter. The diagnosis of metabolic syndrome was made according to the criteria of the American Heart Association/ National Heart, Lung, and Blood Institute. RESULTS: Of the sample, 277 patients had clinical evidence of multinodular nontoxic goiter, 461 met the criteria for the diagnosis of metabolic syndrome, and 132 were found to have both conditions. After adjusting for age, gender, body mass index, nicotinism, parity, alcohol intake, thyroid function, and metabolic syndrome- related pharmacological treatment, metabolic syndrome was found to be an independent risk factor for the occurrence of multinodular non-toxic goiter. The relationship between metabolic syndrome and multi nodular non-toxic goiter was apparent in both men and women. CONCLUSIONS: In this study of euthyroid inpatients, we demonstrate that metabolic syndrome is an independent risk factor for the occurrence of multinodular non-toxic goiter in a geographic area with moderate iodine deficiency. We propose that patients meeting the criteria for metabolic syndrome should be screened for the presence of multinodular non-toxic goiter.


Assuntos
Bócio Nodular/sangue , Bócio Nodular/epidemiologia , Hospitalização , Iodo/deficiência , Síndrome Metabólica/sangue , Síndrome Metabólica/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Iodo/sangue , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco
7.
J Endocrinol Invest ; 31(4): 352-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18475055

RESUMO

The identification of patients with von Hippel-Lindau (VHL) disease dictates accurate genetic counseling of family members, whereas screening for early detection of visceral and neurological involvement is usually performed by a combination of radiological and nuclear medicine techniques such as ultrasonography or contrast-enhanced computed tomography of the upper abdomen, magnetic resonance imaging of the central nervous system and 131I-metaiodobenzylguanidine-scintigraphy. The role of 111-indium-diethylenetriaminepentaacetic acid [111In-DTPA0] octreotide scintigraphy in this clinical context has never been investigated. Here, we report imaging findings in a VHL patient and in 3 consecutive family members undergoing clinical and radiological screening that included [111In-DTPA0] octreotide scintigraphy in addition to the above-mentioned procedures. Somatostatin receptor expression was investigated in vitro by immunohistochemistry in pancreatic tumor sections. On the basis of in vivo and in vitro findings, octreotide long-acting release treatment followed by 90Y-1,4,7,10-Tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid (DOTA0)-Tyr3-octreotide led to a lack of progression in this patient although this result is a possibility which needs to be proved by further investigation and longer follow-up. The results of this study suggest that [111In-DTPA0] octreotide scintigraphy may be helpful in the routine work-up of VHL patients for diagnostic and therapeutic purposes.


Assuntos
Radioisótopos de Índio , Octreotida/análogos & derivados , Ácido Pentético/análogos & derivados , Tomografia Computadorizada de Emissão/métodos , Doença de von Hippel-Lindau/diagnóstico por imagem , Doença de von Hippel-Lindau/genética , Adulto , Feminino , Humanos , Masculino , Doença de von Hippel-Lindau/diagnóstico
8.
Bone ; 35(3): 785-91, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15336617

RESUMO

This study was aimed at evaluating serum osteoprotegerin (OPG) concentrations in a cohort of patients with hyperthyroidism before and after methimazole (MMI) treatment. One hundred fourteen hyperthyroid patients [93 with Graves disease (GD) and 21 with toxic nodular goitre (TNG)] and 68 matched for sex and age healthy subjects were evaluated for serum free-thyroxine (FT4), free-triiodiothyronine (FT3), thyrotropin (TSH), TSH receptor antibodies (TRAb), bone alkaline phosphatase (BALP), C-telopeptides of type-1 collagen (CrossLaps), OPG levels, and bone mineral density (BMD). In hyperthyroid patients, the biochemical evaluations were performed before and after 6 and 12 months of MMI treatment, whereas BMD was measured at baseline and after 12 months of treatment. Hyperthyroidism was more severe in GD than TNG patients. Serum OPG levels were found to be significantly higher in hyperthyroid patients than in the healthy subjects (4.3 pmol/l, range: 1.6-12.0, vs. 2.2 pmol/l, range: 1.4-6.0; P < 0.001), the values being higher in GD patients than TNG. A significant correlation between serum OPG levels and age was found in the healthy subjects (r: 0.48; P < 0.001) but not in hyperthyroid patients (r: -0.03; P = 0.8). In the healthy subjects, serum OPG levels were also positively correlated with both serum FT4 (r: 0.23; P = 0.03) and FT3 (r: 0.24; P = 0.04) levels. In hyperthyroid patients, however, serum OPG was still correlated with FT3 levels (r: 0.38; P < 0.001), whereas the correlation with serum FT4 was lost (r: 0.19; P = 0.06). In hyperthyroid patients, but not in the healthy subjects, serum OPG levels were correlated positively with CrossLaps (r: 0.20; P = 0.03) and negatively with BALP (r: -0.24; P = 0.01) and BMD (r: -0.33; P = 0.01). After 6 months of MMI treatment, serum OPG concentrations decreased significantly in TNG patients (from 3.5 pmol/l, range: 1.6-8.0, to 2.3 pmol/l, range: 1.0-4.3; P < 0.001), whereas a not significant change in OPG levels occurred in GD patients (from 4.8 pmol/l, range: 1.8-12.0, to 4.2 pmol/l, range: 1.0-14.0; P = 0.7). At Month 12 of treatment, serum OPG concentrations were significantly lower than those measured at baseline in both TNG (2.5 pmol/l, range: 1.0-3.1, vs. 3.5 pmol/l, range: 1.6-8.0; P < 0.001) and GD (2.1 pmol/l, range: 1.0-8.6, vs. 4.8 pmol/l, range: 1.8-12.0; P < 0.001). At this time, no significant differences in serum OPG, CrossLaps, and BALP values were found between patients and control subjects. At the end of follow-up, BMD was higher than those measured at baseline but still significantly lower than those measured in the control subjects. This study shows that hyperthyroid patients have serum OPG concentrations significantly higher in comparison with euthyroid subjects, in relation to thyroid hormone excess and high bone turnover. Medical treatment of hyperthyroidism normalizes serum OPG levels in temporal relationship with the normalization of bone metabolism markers, even in presence of persistent abnormal bone structure as determined by ultrasonography.


Assuntos
Glicoproteínas/sangue , Hipertireoidismo/sangue , Hipertireoidismo/tratamento farmacológico , Metimazol/uso terapêutico , Receptores Citoplasmáticos e Nucleares/sangue , Adulto , Idoso , Distribuição de Qui-Quadrado , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteoprotegerina , Receptores do Fator de Necrose Tumoral , Estatísticas não Paramétricas , Hormônios Tireóideos/sangue
9.
Minerva Endocrinol ; 29(4): 161-74, 2004 Dec.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-15765026

RESUMO

Thyroid cancer is the most common endocrine malignancy. More than 90% of primary thyroid cancers are differentiated papillary or follicular types. The treatment of differentiated thyroid carcinoma (DTC) consists of total thyroidectomy and radioactive iodine ablation therapy, followed by L-thyroxine therapy. The extent of initial surgery, the indication for radioiodine ablation therapy and the degree of TSH-suppression are all issues that are still being debated cancers are in relation to the risk of recurrence. Total thyroidectomy reduces the risk of recurrence and facilitates (131)I ablation of thyroid remnants. The aim of radioiodine ablation is to destroy any normal or neoplastic residuals of thyroid tissue. These procedures also improve the sensitivity of thyroglobulin (Tg) as a marker of disease, and increase the sensitivity of (131)I total body scan (TBS) for the detection of persistent or recurrent disease. The aim of TSH-suppressive therapy is to restore euthyroidism and to decrease serum TSH levels, in order to reduce the growth and progression of thyroid cancer. After initial treatment, the objectives of the follow-up of DTC is to maintain adequate thyroxine therapy and to detect persistent or recurrent disease through the combined use of neck ultrasound (US) and serum Tg and (131)I TBS after TSH stimulation. The follow-up protocol should be adapted to the risk of recurrence. Recent advances in the follow-up of DTC are related to the use of recombinant human TSH (rhTSH) in order to stimulate Tg production and the ultrasensitive methods for Tg measurement. Undetectable serum Tg during TSH suppressive therapy with L-T4 does not exclude persistent disease, therefore serum Tg should be measured after TSH stimulation. The results of rhTSH administration and L-thyroxine therapy withdrawal are equivalent in detecting recurrent thyroid cancer, but the use of rhTSH helps to avoid the onset of hypothyroid symptoms and the negative effects of acute hypothyroidism on cardiovascular, hepatic, renal and neurological function. In low-risk DTC patients serum Tg after TSH stimulation, together with ultrasound of the neck, should be used to monitor persistent disease, avoiding diagnostic TBS which has a poor sensitivity. These recommendations do not apply when Tg antibodies are present in the serum, in patients with persistent or recurrent disease or limited thyroid surgery. Low-risk patients may be considered to be in remission when undetectable Tg after TSH stimulation and negative US evaluation of the neck are present. On the contrary, detectable Tg after TSH stimulation is an indicator in selecting patients who are candidates for further diagnostic procedures.


Assuntos
Biomarcadores Tumorais/sangue , Carcinoma Papilar, Variante Folicular/diagnóstico , Radioisótopos do Iodo/uso terapêutico , Tireoglobulina/sangue , Neoplasias da Glândula Tireoide/diagnóstico , Tireoidectomia , Tiroxina/administração & dosagem , Carcinoma Papilar, Variante Folicular/terapia , Humanos , Sensibilidade e Especificidade , Neoplasias da Glândula Tireoide/terapia
10.
J Endocrinol Invest ; 27(8): 774-7, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15636433

RESUMO

Herein we report on a young girl with recurrent, functioning paraganglioma of the organ of Zuckerkandl and severe and sustained arterial hypertension (systolic pressure >200, diastolic pressure >120 mmHg); with evidence of cardiac damage induced by chronic cathecolamine excess. She promptly and steadily improved after the institution of doxazosin (6 mg/day) plus atenolol (50 mg bid) treatment. This case demonstrates that a correct therapeutic strategy in the long-term management of patients with inoperable catecholamine-producing neuroendocrine tumors (pheochromocytomas and paragangliomas) can maintain arterial pressure in the normal range and reverse the cardiac damage induced by chronic cathecolamine excess.


Assuntos
Antagonistas Adrenérgicos alfa/uso terapêutico , Antagonistas Adrenérgicos beta/uso terapêutico , Atenolol/uso terapêutico , Catecolaminas/fisiologia , Doxazossina/uso terapêutico , Cardiopatias/tratamento farmacológico , Neoplasias Cardíacas/tratamento farmacológico , Hipertensão/tratamento farmacológico , Glomos Para-Aórticos/diagnóstico por imagem , Paraganglioma/complicações , 3-Iodobenzilguanidina , Pressão Sanguínea/efeitos dos fármacos , Catecolaminas/sangue , Criança , Quimioterapia Combinada , Eletrocardiografia/efeitos dos fármacos , Feminino , Cardiopatias/patologia , Neoplasias Cardíacas/diagnóstico por imagem , Neoplasias Cardíacas/patologia , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Hipertrofia Ventricular Esquerda/patologia , Paraganglioma/diagnóstico por imagem , Cintilografia , Compostos Radiofarmacêuticos
11.
J Inorg Biochem ; 93(3-4): 181-9, 2003 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-12576280

RESUMO

This work reports on the synthesis, characterization and biological activity of new coordination compounds of the type [M(TSDTM)X(2)] (M=Pt(II), Pd(II); X=Cl, Br; TSDTM=ter-butylsarcosine(S-methyl)dithiocarbamate) and [Pd(TSDT)X](n) (TSDT=ter-butylsarcosinedithiocarbamate) in order to study their behavior as potential antitumor agents. All the synthesized compounds were characterized by means of elemental analysis, FT-IR, (1)H and (13)C-NMR spectroscopy and thermogravimetric analysis, suggesting a chelate S,S' structure of the TSDTM/TSDT ligand in a square-planar geometry. Finally, the synthesized complexes have been tested for in vitro cytotoxic activity against human leukemic HL60 and adenocarcinoma HeLa cells; the most active compound [Pt(TSDTM)Br(2)], characterized by IC(50) values very similar to those of the reference compound (cisplatin), was also tested for in vitro nephrotoxicity showing a very low renal cytotoxicity as compared to cisplatin itself.


Assuntos
Paládio/química , Platina/química , Sarcosina/análogos & derivados , Sarcosina/síntese química , Tiocarbamatos/síntese química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Divisão Celular/efeitos dos fármacos , Células HL-60 , Células HeLa , Humanos , Rim/citologia , Rim/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Masculino , Conformação Molecular , Ratos , Ratos Wistar , Sarcosina/química , Sarcosina/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Tiocarbamatos/química , Tiocarbamatos/farmacologia
12.
J Endocrinol Invest ; 25(5): 442-6, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12035941

RESUMO

Despite the observation that parity may increase the risk of thyroid carcinoma, very few studies have investigated the possible repercussion of parity on thyroid benign pathology. Recently, parity has been identified as one of the factors contributing to a larger thyroid size in healthy females. The aim of this work was to investigate a possible role for parity on the prevalence of multinodular goiter in iodine deficient areas. For this purpose, the reproductive histories of 2 cohorts of women, normal (Group I, 235 cases) and non-toxic multinodular goiter (NTMNG) affected (Group II, 274 cases) were compared. All subjects were euthyroid and had no previous history of thyroid function abnormalities. The number of full-term previous pregnancies (2.55+/-0.11 vs 1.77+/-0.10) and age (47.7+/-0.76 vs 42.3+/-0.83 yr) were found significantly higher (p<0.001) in multinodular goiter (MNG) patients than controls. Parity and age were found to be directly correlated (p<0.001), nevertheless the partial correlation coefficients demonstrated an independent and statistically significant difference for both variables between normal and NTMNG. Therefore, the independent effects of parity and age were further investigated. The effect of age on NTMNG prevalence seems to be weaker, in fact significant differences (p<0.001) for age between patients and controls were detected only when the effect of parity was absent (nulliparous), while with increasing gestations the effect of age disappeared. Our results indicate that age plays a minor role compared to parity which can therefore be considered as a stronger risk factor. In conclusion, the present study shows that, at least in iodine deficient regions, non-toxic multinodular goiter women show a statistically significant higher parity rate than healthy controls. Age may play a certain role but only when additional stronger risk factors are absent.


Assuntos
Bócio Nodular/epidemiologia , Iodo/deficiência , Paridade , Adulto , Envelhecimento/fisiologia , Deficiências Nutricionais/epidemiologia , Feminino , Humanos , Itália/epidemiologia , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
13.
Minerva Endocrinol ; 26(4): 231-8, 2001 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-11782708

RESUMO

Neuroendocrine tumours are frequently malignant and have often reached an advanced stage by the time of diagnosis when they are inoperable, accompanied by severe symptoms, sometimes of an endocrine nature. Current therapeutic procedures include surgery, embolisation of hepatic metastases, local radiotherapy, biotherapy and chemotherapy. Over the years somatostatin analogs, of which octreotide is the first form, have become increasingly important in the treatment of patients with neuroendocrine tumours. A major step forward in analog treatment is represented by the development of slow-release formulas which do not require multiple daily injections and reduce the onset of resistance. The treatment of neuroendocrine tumours in the future will be based on the increased use of somatostatin analogs alone or in association with interferon or chemotherapy, and will also include surgery, radiometabolic therapy and targeted irradiation of the tumour.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Neoplasias Gastrointestinais/terapia , Tumores Neuroendócrinos/terapia , Neoplasias Pancreáticas/terapia , Terapia Combinada , Humanos , Octreotida/uso terapêutico , Receptores de Somatostatina/antagonistas & inibidores
14.
J Clin Endocrinol Metab ; 85(1): 179-82, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10634384

RESUMO

Many studies have shown that acromegaly has relevant effects on cardiovascular system, but few data are available regarding the effects of short-term acromegaly on heart morphology and function. These data would help to clarify the natural history of acromegalic disease and could provide new insight into the mechanisms of GH action on the human heart. Therefore, we studied by Doppler echocardiography a group of 10 young subjects strictly selected as having short-term (<5 yr) uncomplicated acromegaly. The results of this study have shown that shortterm acromegaly is characterized by significantly increased left ventricular mass (P<0.005), with normal relative wall thickness, associated with Doppler indices of diastolic function in the normal range. Furthermore, stroke index and cardiac index were significantly enhanced in the patient group (P<0.01 and P<0.001, respectively), whereas systemic vascular resistance was significantly reduced (P<0.001). In conclusion, our study shows that short-term acromegaly significantly affects the heart, but, at variance with long-term disease, it is characterized by increased left ventricular mass, with eccentric remodeling and normal diastolic function. Moreover, short-term acromegaly induces a high cardiac output state with reduction of systemic vascular resistance.


Assuntos
Acromegalia/fisiopatologia , Adenoma/fisiopatologia , Hemodinâmica/fisiologia , Hormônio do Crescimento Humano/fisiologia , Neoplasias Hipofisárias/fisiopatologia , Acromegalia/diagnóstico por imagem , Adenoma/complicações , Adulto , Pressão Sanguínea/fisiologia , Circulação Coronária/fisiologia , Ecocardiografia Doppler , Feminino , Humanos , Masculino , Neoplasias Hipofisárias/complicações , Função Ventricular Esquerda/fisiologia
15.
Thyroid ; 10(12): 1081-5, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11201853

RESUMO

Recent studies have raised doubts about the efficacy of the postoperative use of levothyroxine (LT4) suppressive doses in patients who underwent thyroid surgery for multinodular goiter. The purpose of this retrospective study was to examine the efficacy of different doses of LT4 in preventing postsurgical recurrences of simple multinodular goiter and to identify a marker that could be useful in discriminating patients with a higher risk of developing recurrence. Two hundred thirty-two patients (57 male, 175 female) operated for nontoxic multinodular goiter were divided into two groups: (I) patients with normal postsurgery thyrotropin (TSH) levels (0.25 to 4.5 mU/L) and (II) patients with elevated postsurgery TSH levels (>4.5 mU/L). All patients were subjected to replacement (1.3 microg LT4/kg/day) or suppressive (1.7 microg LT4/kg/day) doses of LT4, and they were followed for a median period of 6 years (range 2 to 12). No statistical difference was found for sex, age, and postsurgery serum TSH between patients submitted to suppressive and replacement therapy. The ultrasound (US) detection of new postsurgery nodules of at least 0.5 cm maximum diameter was considered a recurrence of disease and was found in 10% of the cases studied. Patients with normal postsurgery serum TSH showed a high recurrence rate (30.4%) when submitted to lower daily doses of LT4. In patients with elevated postsurgery serum TSH, the rate of nodular goiter recurrence did not vary with different types of LT4 therapy. In conclusion, our results suggest that the postsurgical serum TSH is useful for prediction of nodular goiter recurrence, as it reflects the amount of residual functioning thyroid tissue in the cervical area. It may also be indicative of patients who might benefit from LT4 suppressive therapy.


Assuntos
Doenças Endêmicas , Bócio Nodular/cirurgia , Iodo/deficiência , Tireotropina/sangue , Tiroxina/uso terapêutico , Adulto , Terapia Combinada , Feminino , Bócio Nodular/tratamento farmacológico , Bócio Nodular/epidemiologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Período Pós-Operatório , Recidiva
16.
Cardiologia ; 44(5): 443-9, 1999 May.
Artigo em Italiano | MEDLINE | ID: mdl-10389349

RESUMO

BACKGROUND: Thyroid hormones greatly affect the cardiovascular system. Although the effects of overt hyperthyroidism on the cardiovascular system have been diffusely studied, only in the last years the effects of subclinical hyperthyroidism on the heart have been investigated. Subclinical hyperthyroidism is a symptomatic or asymptomatic condition with an absent response of thyrotropin (TSH) to thyrotropin-releasing hormone in the presence of normal serum levels of thyroid hormones for the general population, though supraoptimal for the individual. The more frequent causes of endogenous subclinical hyperthyroidism are multinodular goiter, toxic, adenoma and Graves's disease, whereas the exogenous causes are induced by levothyroxine (LT4) therapy used to suppress TSH in patients with nontoxic goiter and differentiated thyroid cancer. This paper reports our experience derived from the study of 60 patients with subclinical hyperthyroidism due to TSH-suppressive therapy with LT4 compared to normal subjects. METHODS: Patients (9 males and 51 females, mean age 39 +/- 10 years) were studied by complete Doppler echocardiography, standard and 24 hour ECG Holter monitoring, exercise test with cycloergometer, and radionuclide ventriculography at rest and during fixed workload (75 W). RESULTS: Holter monitoring showed a significant increase in mean 24 hour heart rate (80 +/- 10 vs 70 +/- 9 b/min, p < 0.001) and supraventricular arrhythmias (42 vs 12 patients, p < 0.003). Echocardiography showed an increase in left ventricular mass index (94 +/- 13 vs 80 +/- 18 g/m2, p < 0.001) due to increased septal and posterior wall thickness. At rest, echocardiographic indices of systolic function (fractional shortening and mean corrected velocity of circumferential fiber shortening) were higher in patients than in controls (fractional shortening 40 +/- 6 vs 34 +/- 4%, p < 0.001; mean corrected velocity of circumferential fiber shortening 1.23 +/- 0.17 vs 1.05 +/- 0.14 circ/s, p < 0.001), while the Doppler indices of diastolic function were significantly impaired as documented by the reduced E/A ratio (1.18 +/- 0.3 vs 1.8 +/- 0.5, p < 0.001) and the prolonged isovolumic relaxation time (94 +/- 13 vs 78 +/- 12 ms, p < 0.001). Exercise tolerance was also significantly impaired in patients with subclinical hyperthyroidism: maximal exercise time (6.4 +/- 0.7 vs 9.4 +/- 1.4 min, p < 0.001) and peak workload (81 +/- 11 vs 121 +/- 17 W, p < 0.001) were significantly reduced and radionuclide ventriculography showed a decrease in ejection fraction during exercise (from 62 +/- 7 to 53 +/- 8%, p < 0.002). CONCLUSIONS: Persistent subclinical hyperthyroidism by TSH-suppressive doses of LT4 significantly affects heart morphology and function. Thus, we suggest that a complete suppression of TSH must be recommended only in patients with differentiated thyroid cancer, while in patients with begin thyroid disease it could be sufficient to maintain subnormal TSH levels.


Assuntos
Hipertireoidismo/induzido quimicamente , Hipertireoidismo/patologia , Tiroxina/efeitos adversos , Adulto , Feminino , Coração/fisiopatologia , Humanos , Hipertireoidismo/fisiopatologia , Masculino , Miocárdio/patologia
17.
J Pept Res ; 53(4): 442-52, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10406222

RESUMO

In order to investigate the antiproliferative properties of antamanide, we have synthesized and studied two antamanide analogs where the phenylalanine residue in positions 6 or 9 is substituted by tyrosine, their corresponding linear forms and the cyclic and linear des Phe5,Phe6-Tyr9-analogs. Antamanide and its biologically active synthetic analogs are able to form highly stable complexes with metal ions, particularly Na+, K+ and Ca2+. We studied the ion-binding properties of the Tyr-antamanide analogs by CD and Tb3+ -mediated fluorescence in acetonitrile. In this medium the far-and near-UV CD spectra of the neat Tyr6-antamanide analog are very similar to that of the parent cyclic decapeptide. Substantial differences occur on the contrary in the CD spectra of the neat Tyr9-antamanide, particularly in the regions at 220 nm and 270-290 nm. In acetonitrile, as already found for antamanide, the interaction with the above-mentioned metal ions always produces evident changes in the far- and near-UV CD spectra of both analogs. On the contrary, the CD spectra of the linear deca- and octa- and of the cyclic octa-analogs are affected by the presence of metal ions only in the near-UV region. In the same solvent the Tb3+ -mediated fluorescence spectra of all the synthetic peptides are remarkably affected by the addition of ions. On the basis of the spectral total changes, by using either or both the spectroscopic techniques, it has been possible to determine the ion binding constants for all the linear and cyclic Tyr-antamanide analogs and to compare them with that of the parent peptide. The antitoxic and antiproliferative activities of these antamanide analogs have been tentatively correlated to their ion-binding properties. A preliminary account of this work was given in (1).


Assuntos
Antídotos/metabolismo , Antídotos/farmacologia , Metais/metabolismo , Peptídeos Cíclicos/metabolismo , Peptídeos Cíclicos/farmacologia , Acetonitrilas/química , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Antídotos/química , Cálcio/metabolismo , Cátions/metabolismo , Divisão Celular/efeitos dos fármacos , Dicroísmo Circular , Masculino , Melanoma/tratamento farmacológico , Melanoma/secundário , Metais Terras Raras/metabolismo , Camundongos , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Peptídeos Cíclicos/química , Faloidina/farmacologia , Potássio/metabolismo , Sódio/metabolismo , Espectrometria de Fluorescência , Térbio/metabolismo , Células Tumorais Cultivadas
18.
Clin Cardiol ; 21(10): 777-9, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9789703

RESUMO

Even today, heart failure due to doxorubicin-induced dilated cardiomyopathy seems to have a poor prognosis, as it is often irreversible and relatively unresponsive to standard medical treatment. This paper describes the first case of a patient complaining of severe symptoms of congestive heart failure due to doxorubicin-induced dilated cardiomyopathy unresponsive to standard medical treatment (digoxin, diuretics, and angiotensin-converting enzyme inhibitor), who showed complete clinical recovery and significant improvement of left ventricular dysfunction after carvedilol treatment. It also illustrates the possibility that carvedilol may be a first-choice drug for the treatment of this disease.


Assuntos
Antagonistas Adrenérgicos alfa/uso terapêutico , Antagonistas Adrenérgicos beta/uso terapêutico , Antineoplásicos/efeitos adversos , Carbazóis/uso terapêutico , Cardiomiopatia Dilatada/induzido quimicamente , Cardiomiopatia Dilatada/tratamento farmacológico , Doxorrubicina/efeitos adversos , Propanolaminas/uso terapêutico , Antagonistas Adrenérgicos alfa/administração & dosagem , Antagonistas Adrenérgicos beta/administração & dosagem , Adulto , Carbazóis/administração & dosagem , Cardiomiopatia Dilatada/diagnóstico por imagem , Carvedilol , Feminino , Seguimentos , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Propanolaminas/administração & dosagem , Radiografia Torácica , Fatores de Tempo
19.
J Endocrinol Invest ; 21(11): 748-52, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9972674

RESUMO

Thyroid autoimmunity and dysfunction are a well known side effect of IFN alpha therapy for viral hepatitis and tumors, while the IFN beta effects on the thyroid gland in neurological patients have not been studied. The aim of this longitudinal study was to look for the appearance of thyroid autoimmunity as well as for the occurrence of overt thyroid disease in the patients affected by multiple sclerosis (MS) treated with IFN beta 1b. Eight patients (4 males, 4 females) undergoing r-IFN beta 1b treatment (8 M.U. every other day for 9 months) for relapsing remitting multiple sclerosis entered the study. We have analyzed thyroid function parameters and auto antibody levels before and after 1, 2, 3, 6 and 9 months of therapy. None of them referred to familiar thyroid pathology or presented clinically overt thyroid disease except for one patient (case 4) who showed TPO-Ab pretreatment positivity and another (case 8) who was in therapy with Levothyroxine 100 microg/die for multinodular goiter. The number of patients with appearance of thyroid antibodies has slowly increased, until the third month of therapy with 3 patients out of 7 positive for TPO-Ab. The only case of overt thyroid dysfunction reported by us appeared after nine months of therapy and consisted of a hypothyroidism. Our data suggest that short-term interferon beta treatment is able to induce thyroid autoimmunity (42.8%) and dysfunction (12.5%).


Assuntos
Autoimunidade , Interferon beta/efeitos adversos , Esclerose Múltipla/terapia , Glândula Tireoide/imunologia , Adulto , Autoanticorpos/sangue , Doenças Autoimunes/induzido quimicamente , Feminino , Humanos , Interferon beta/uso terapêutico , Iodeto Peroxidase/imunologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Tireoglobulina/imunologia , Doenças da Glândula Tireoide/induzido quimicamente , Doenças da Glândula Tireoide/imunologia , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
20.
J Clin Endocrinol Metab ; 80(7): 2222-6, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7608283

RESUMO

Thyroid-stimulating hormone (TSH) suppressive therapy with levothyroxine (L-T4) may cause adverse cardiac effects such as rhythm disturbances and ventricular hypertrophy. The latter is a predisposing condition to diastolic dysfunction. Thus, this study was designed to assess the effect of long-term TSH suppressive therapy on cardiac diastolic function. Because beta-blockade is known to reduce ventricular hypertrophy in patients on L-T4 therapy, we also tried to determine whether the addition of a beta-blocker to L-T4 improved diastolic function. Twenty-five patients (21 female and 4 male; mean age 41 +/- 10 yr) on TSH suppressive therapy for 3-9 yr (9 for differentiated carcinoma and 16 for nontoxic goiter) and 20 control subjects were studied. A subgroup of 10 patients, selected for the presence of symptoms and signs of adrenergic overactivity, was treated for 4 months with the beta-blocker bisoprolol (4.25 +/- 1.2 mg/day), and their maintaining L-T4 therapy was unchanged. In the patient group, left ventricular mass was significantly increased (P < 0.001), isovolumic relaxation time was prolonged (P < 0.001), and early diastolic filling velocity was markedly reduced (P < 0.001), whereas late diastolic filling was increased (P < 0.005). Consequently, the early-to-late diastolic flow velocity ratio was markedly decreased (P < 0.001). These alterations were more pronounced in the subgroup of patients with evidence of adrenergic overactivity. In these patients, beta-blockade induced a significant regression of cardiac hypertrophy and improved diastolic dysfunction. In particular, isovolumic relaxation time decreased (P < 0.01) and the early-to-late flow velocity ratio increased significantly (P < 0.01). Both indices reached values after beta-blockade that were no longer different from those of asymptomatic patients. It is concluded that long-term L-T4 therapy increases myocardial mass and causes relevant diastolic dysfunction, particularly in those patients with evidence of mild hyperthyroidism and adrenergic overactivity. Both myocardial hypertrophy and diastolic dysfunction are significantly improved by adrenergic beta-blockade.


Assuntos
Bisoprolol/uso terapêutico , Cardiomegalia/tratamento farmacológico , Diástole/efeitos dos fármacos , Bócio/tratamento farmacológico , Neoplasias da Glândula Tireoide/tratamento farmacológico , Tiroxina/efeitos adversos , Adulto , Cardiomegalia/induzido quimicamente , Ecocardiografia Doppler , Feminino , Bócio/fisiopatologia , Frequência Cardíaca , Ventrículos do Coração , Humanos , Masculino , Pessoa de Meia-Idade , Sístole , Neoplasias da Glândula Tireoide/fisiopatologia , Tireotropina/antagonistas & inibidores , Tiroxina/sangue , Tiroxina/uso terapêutico , Tri-Iodotironina/sangue
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA