Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
1.
Eur J Neurol ; 24(2): 446-449, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27982500

RESUMO

BACKGROUND AND PURPOSE: Growth hormone (GH)/insulin-like growth factor 1 (IGF-1) axis abnormalities in multiple sclerosis (MS) suggest their role in its pathogenesis. Interferon ß (IFN-ß) efficacy could be mediated also by an increase of IGF-1 levels. A 2-year longitudinal study was performed to estimate the prevalence of GH and/or IGF-1 deficiency in clinically isolated syndrome (CIS) patients and their correlation with conversion to MS in IFN treated patients. METHODS: Clinical and demographic features of CIS patients were collected before the start of IFN-ß-1b. IGF-1 levels and GH response after arginine and GH releasing hormone + arginine stimulation tests were assessed. Clinical and magnetic resonance imaging evaluations were performed at baseline, 1 year and 2 years. RESULTS: Thirty CIS patients (24 female) were enrolled. At baseline, four patients (13%) showed a hypothalamic GH deficiency (GHD), whilst no one had a pituitary GHD. Baseline demographic, clinical and radiological data were not related to GHD, whilst IGF-1 levels were inversely related to age (P < 0.001) and GH levels (P = 0.03). GH and IGF-1 serum mean levels were not significantly modified after 1 and 2 years of treatment in the whole group, although 3/4 GHD patients experienced a normalization of GH levels, whilst one dropped out. After 2 years of treatment 13/28 (46%) patients converted to MS. The presence of GHD and GH and IGF-1 levels were not predictive of relapses, new T2 lesions or conversion occurrence. CONCLUSIONS: Growth hormone/IGF-1 axis function was found to be frequently altered in CIS patients, but this was not related to MS conversion. Patients experienced an improvement of GHD during IFN therapy. Longer follow-up is necessary to assess its impact on disease progression.


Assuntos
Hormônio do Crescimento Humano/sangue , Fator de Crescimento Insulin-Like I/análise , Interferon beta-1b/uso terapêutico , Esclerose Múltipla/sangue , Adulto , Arginina/farmacologia , Progressão da Doença , Eletrodiagnóstico , Feminino , Seguimentos , Hormônio Liberador de Hormônio do Crescimento/farmacologia , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/fisiopatologia , Exame Neurológico , Resultado do Tratamento
2.
J Endocrinol Invest ; 36(9): 712-5, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23563248

RESUMO

BACKGROUND: GPR7, the endogenous coupled receptor for neuropeptide B and neuropeptide W, is expressed in several regions of the central nervous system, which are involved in the regulation of feeding behavior. GPR7 affects the regulation of energy balance through a mechanism independent of leptin and melanocortin pathways. AIM: Aim of this study was to investigate whether GPR7 gene mutations can be detected in human subjects and, in that event, if they are differently distributed among lean and obese subjects. SUBJECTS AND METHODS: The coding region of GPR7 were sequenced in 150 obese patients and 100 normal-weight unrelated controls. Functional studies of the allelic variants were performed. RESULTS: One genetic GPR7 variant was found (Tyr135Phe - rs33977775) in obese subjects (13.3%) and lean control (25%). Functional studies did not reveal significant differences between the wild type and the Tyr135Phe allelic variants in their NPW-mediated capacity to inhibit forskolin-induced cAMP production. CONCLUSIONS: Screening of GPR7 gene mutations among lean and obese subjects revealed a Tyr135Phe allelic variant that was fairly common in the study population. As indicated by in vitro and in silico studies, this variant is unlikely to cause a functional derangement of the receptor.


Assuntos
Obesidade/genética , Receptores Acoplados a Proteínas G/genética , Receptores de Neuropeptídeos/genética , Magreza/genética , Adulto , Alelos , Substituição de Aminoácidos , Animais , Células COS , Chlorocebus aethiops , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Receptores Acoplados a Proteínas G/fisiologia , Receptores de Neuropeptídeos/fisiologia
3.
Endocrinology ; 152(8): 3082-92, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21628384

RESUMO

RT-PCR shows that mouse skeletal muscle contains type-2 iodothyronine deiodinase (D2) mRNA. However, the D2 activity has been hard to measure. Except for newborn mice, muscle homogenates have no detectable activity. However, we have reported D2 activity in mouse muscle microsomes. As the mRNA, activity is higher in slow- than in fast-twitch muscle. We addressed here the major problems in measuring D2 activity in muscle by: homogenizing muscle in high salt to improve yield of membranous structures; separating postmitochondrial supernatant between 38 and 50% sucrose, to eliminate lighter membranes lacking D2; washing these with 0.1 M Na(2)CO(3) to eliminate additional contaminating proteins; pretreating all buffers with Chelex, to eliminate catalytic metals; and eliminating the EDTA from the assay, as this can bind iron that enhances dithiothreitol oxidation and promotes peroxidation reactions. Maximum velocity of T(3) generation by postgradient microsomes from red muscles was approximately 1100 fmol/(h · mg) protein with a Michaelis-Menten constant for T(4) of 1.5 nM. D2-specific activity of Na(2)CO(3)-washed microsomes was 6-10 times higher. The enrichment in D2 activity increased in parallel with the capacity of microsomes to load (sarco/endoplasmic reticulum Ca(2+)-ATPase) and bind Ca(2+) (calsequestrin), indicating that D2 resides in the inner sarcoplasmic reticulum, close to the nuclei. The presence of D3 in the sarcolemma suggests that the most of D2-generated T(3) acts locally. Estimates from maximum velocity, Michaelis-Menten constant, and muscle T(4) content suggest that mouse red, type-1, aerobic mouse muscle fibers can generate physiologically relevant amounts of T(3) and, further, that muscle D2 plays an important role in thyroid hormone-dependent muscle thermogenesis.


Assuntos
Iodeto Peroxidase/metabolismo , Músculo Esquelético/enzimologia , Animais , Cálcio/metabolismo , Iodeto Peroxidase/análise , Iodeto Peroxidase/genética , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/análise , Retículo Sarcoplasmático/enzimologia , Termogênese , Iodotironina Desiodinase Tipo II
4.
Endocrinology ; 152(8): 3093-102, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21652727

RESUMO

Mice with ablation of the Thra gene have cold intolerance due to an as yet undefined defect in the activation of brown adipose tissue (BAT) uncoupling protein (UCP). They develop an alternate form of facultative thermogenesis, activated at temperatures below thermoneutrality and associated with hypermetabolism and reduced sensitivity to diet-induced obesity. A consistent finding in Thra-0/0 mice is increased type-2 iodothyronine deiodinase (D2) mRNA in skeletal muscle and other tissues. With an improved assay to measure D2 activity, we show here that this enzyme activity is increased in proportion to the mRNA and as a function of the ambient cold. The activation is mediated by the sympathetic nervous system in Thra-0/0, as it is in wild-type genotype mice, but the sympathetic nervous system effect is greater in Thra-0/0 mice. Using D2-ablated mice (Dio2-/-), we reported elsewhere and show here that, in spite of sharing a severe deficiency in BAT thermogenesis with Thra-0/0 and UCP1-knockout mice, they do not have an increase in oxygen consumption, and they gain more weight than wild-type controls when fed a high-fat diet. UCP3 mRNA is highly responsive to thyroid hormone, and it is increased in Thra-0/0 mice, particularly when fed high-fat diets. We show here that muscle UCP3 mRNA in hypothyroid Thra-0/0 mice is responsive to small dose-short regimens of T(4), indicating a role for locally, D2-generated T(3). Lastly, we show that bile acids stimulate not only BAT but also muscle D2 activity, and this is associated with stimulation of muscle UCP3 mRNA expression provided T(4) is present. These observations strongly support the concept that enhanced D2 activity in Thra-0/0 plays a critical role in their alternate form of facultative thermogenesis, stimulating increased fat oxidation by increasing local T(3) generation in skeletal muscle.


Assuntos
Iodeto Peroxidase/fisiologia , Músculo Esquelético/enzimologia , Receptores alfa dos Hormônios Tireóideos/metabolismo , Animais , Iodeto Peroxidase/genética , Canais Iônicos/genética , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Mitocondriais/genética , RNA Mensageiro/análise , Termogênese , Receptores alfa dos Hormônios Tireóideos/deficiência , Proteína Desacopladora 3 , Iodotironina Desiodinase Tipo II
5.
J Endocrinol Invest ; 34(5): 395-407, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21427525

RESUMO

T4 is a prohormone secreted by the thyroid. T4 has a long half life in circulation and it is tightly regulated to remain constant in a variety of circumstances. However, the availability of iodothyronine selenodeiodinases allow both the initiation or the cessation of thyroid hormone action and can result in surprisingly acute changes in the intracellular concentration of the active hormone T3, in a tissue- specific and chronologically-determined fashion, in spite of the constant circulating levels of the prohormone. This fine-tuning of thyroid hormone signaling is becoming widely appreciated in the context of situations where the rapid modifications in intracellular T3 concentrations are necessary for developmental changes or tissue repair. Given the increasing availability of genetic models of deiodinase deficiency, new insights into the role of these important enzymes are being recognized. In this review, we have incorporated new information regarding the special role played by these enzymes into our current knowledge of thyroid physiology, emphasizing the clinical significance of these new insights.


Assuntos
Iodeto Peroxidase/fisiologia , Animais , Retroalimentação Fisiológica , Humanos , Estrutura Molecular , Doenças da Glândula Tireoide/fisiopatologia , Glândula Tireoide/enzimologia , Glândula Tireoide/fisiologia , Tiroxina/química , Tiroxina/metabolismo , Tri-Iodotironina/química , Tri-Iodotironina/metabolismo
6.
J Endocrinol Invest ; 30(2): 104-10, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17392599

RESUMO

Non-alcoholic fatty liver disease is a common finding in obese subjects, and increasing evidence has been provided suggesting that it represents the hepatic component of the metabolic syndrome. The aim of this study was to evaluate whether the extent of liver enlargement is related to the severity of the metabolic syndrome in obese women. The relationship between ultrasound- measured hepatic left lobe volume (HLLV) and various features of the metabolic syndrome was evaluated in 85 obese women. The mean+/-SD value of HLLV in obese women was 431+/-214 ml (range 46-1019 ml) while it was 187+/-31 ml (range 143-258 ml) in lean subjects. In a multiple logistic regression analysis, ultrasound-measured intra-abdominal fat was the only anthropometric measure independently associated with HLLV. A strong positive association was found between HLLV and serum liver enzymes, triglycerides, glucose, insulin, uric acid, C reactive protein, systolic and diastolic blood pressure, while a negative correlation was observed between HLLV and HDL cholesterol. The values of HLLV corresponding to the cut-off values of various risk factors for the diagnosis of the metabolic syndrome were calculated, yielding a mean value of 465 ml. In conclusion, ultrasound measurement of HLLV represents a simple, reliable and low-cost tool for the evaluation of liver involvement in the metabolic syndrome. The strong association between liver enlargement and various cardiovascular risk factors associated with insulin resistance supports the role of liver steatosis as an important link among the many facets of the metabolic syndrome in human obesity.


Assuntos
Fígado/anatomia & histologia , Fígado/diagnóstico por imagem , Síndrome Metabólica/diagnóstico por imagem , Obesidade/diagnóstico por imagem , Adulto , Idoso , Índice de Massa Corporal , Fígado Gorduroso/complicações , Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/patologia , Feminino , Humanos , Gordura Intra-Abdominal/diagnóstico por imagem , Gordura Intra-Abdominal/patologia , Fígado/patologia , Síndrome Metabólica/complicações , Síndrome Metabólica/patologia , Pessoa de Meia-Idade , Obesidade/complicações , Ultrassonografia
7.
J Clin Endocrinol Metab ; 89(6): 2678-83, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15181041

RESUMO

Haptoglobin (Hp) is a glycoprotein involved in the acute phase response to inflammation. Our previous findings indicate that Hp mRNA and protein are present in the adipose tissue of rodents and that Hp gene expression is up-regulated in obese models. The aim of the present study was to establish whether Hp could be considered a marker of obesity in humans. In 312 subjects, serum Hp was correlated directly with body mass index (BMI), leptin, C-reactive protein (CRP), and age. In a multivariate stepwise regression analysis, BMI and CRP were independent determinants of serum Hp in females, with BMI having the strongest effect. CRP and age were independent determinants of serum Hp in males, although explaining only a modest percentage of the total variability. Serum Hp was positively associated with body fat, as assessed by dual-energy x-ray absorptiometry, both in female and in male groups. The level of significance improved when serum Hp was analyzed against fat mass adjusted for lean mass. Finally, Northern and Western blot analyses performed in biopsies of sc abdominal fat from 20 obese individuals showed the presence of Hp mRNA and protein in the human adipose tissue. In conclusion, serum Hp constitutes a novel marker of adiposity in humans, and the adipose tissue likely contributes to determine its levels.


Assuntos
Tecido Adiposo/metabolismo , Índice de Massa Corporal , Haptoglobinas/metabolismo , Obesidade/sangue , Adolescente , Adulto , Idoso , Biomarcadores/sangue , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Obesidade/diagnóstico
8.
J Endocrinol Invest ; 27(2): RC5-7, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15129802

RESUMO

Thyroid dysfunction is associated with metabolic changes that affect mass and adipocyte function, as well as lipid and carbohydrate metabolism. Adipose tissue performs complex metabolic and endocrine functions. Leptin and adiponectin are two of the most important adipocytokines, both involved in the regulation of intermediate metabolism. The aim of this study was to evaluate the relationships between thyroid status and circulating levels of the two adipose tissue hormones. We studied 15 patients with hyperthyroidism, 15 patients with hypothyroidism and 15 euthyroid subjects, all matched by sex, age and body mass index (BMI). Serum concentrations of free thyroxine, free tri-iodothyronine, thyrotropin, leptin and adiponectin and anthropometric parameters (weight, height, BMI) were assessed. No significant difference was found among the 3 groups, as assessed by Student's t-test, both for adiponectin and leptin. We conclude that metabolic changes associated with thyroid dysfunction are not related to variations in serum levels of adiponectin or leptin.


Assuntos
Tecido Adiposo/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular , Leptina/sangue , Proteínas/metabolismo , Glândula Tireoide/metabolismo , Adiponectina , Adulto , Antropometria , Estudos de Casos e Controles , Feminino , Humanos , Hipertireoidismo/metabolismo , Hipotireoidismo/metabolismo , Masculino , Pessoa de Meia-Idade , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue
9.
J Endocrinol Invest ; 26(10): 950-5, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14759065

RESUMO

Several natural or synthetic chemicals have been indicated as potential thyroid disruptors. The development of in vitro assays has been recommended to comprehensively assess the potential thyroid disrupting activity of a substance or a complex mixture. In this study, 12 substances suspected for acting as thyroid disruptors were tested for their ability to inhibit TSH-stimulated cAMP production in vitro. Those substances producing an inhibition were further studied to establish the level at which they interfere with this step of thyroid cell function. Using Chinese hamster ovary cells (CHO) transfected with the recombinant human TSH receptor, a dose-dependent inhibition of TSH-stimulated adenylate cyclase activity was produced by 1,1-bis-(4-chlorphenyl)-2,2,2-trichloroethan (DDT), Aroclor 1254 and Melissa Officinalis. All three substances also inhibited the cAMP production stimulated by TSH receptor antibody. Melissa Officinalis produced a significant inhibition of TSH binding to its receptor and of antibody binding to TSH, while no significant changes were produced by Aroclor 1254 or DDT in these assays. These data suggest that principles contained in Melissa Officinalis may block the binding of TSH to its receptor by acting both on the hormone and the receptor itself, while DDT and Aroclor 1254 affect cAMP production mainly at post-receptor step. In conclusion, we have developed a set of in vitro assays that allow investigation into the effect of thyroid disruptors on the TSH-mediated activation of the cAMP cascade. These assays may be useful to identify the mechanism of action of thyroid disruptors, coming beside and supporting animal studies or epidemiological surveys.


Assuntos
Adenilil Ciclases/metabolismo , Antitireóideos/toxicidade , DDT/toxicidade , Poluentes Ambientais/toxicidade , Melissa/toxicidade , Glândula Tireoide/efeitos dos fármacos , Tireotropina/antagonistas & inibidores , Animais , Autoanticorpos/metabolismo , Células CHO , Colforsina/farmacologia , Cricetinae , AMP Cíclico/biossíntese , Relação Dose-Resposta a Droga , Ativadores de Enzimas/farmacologia , Imunoglobulinas Estimuladoras da Glândula Tireoide , Radioimunoensaio , Receptores da Tireotropina/antagonistas & inibidores , Receptores da Tireotropina/metabolismo , Glândula Tireoide/metabolismo , Tireotropina/metabolismo
10.
Phytochemistry ; 34(3): 847-52, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7764155

RESUMO

Two new flavonoids, 5,8-dihydroxy-4'-methoxy-6,7-methylenedioxyisoflavone and carthamidin-7-O-alpha-L-rhamnopyranoside and a new triterpenoid saponin, 3 beta,16 beta,22 beta,24-tetrahydroxy-olean-12- ene-3-beta-yl-]beta-D-glucopyranosyl (1-->2)]-alpha-L-rhamnopyranoside (junceoside), were isolated from Spartium junceum. Their structures were elucidated by means of IR, UV, MS, 1H, 13C NMR, 13C NMR DEPT and 2D NMR experiments. Apigenin-7-O-beta-D-glucopyranoside and genistein-8-C-beta-D-glucopyranoside, never previously found in this plant, were also isolated.


Assuntos
Flavonoides/isolamento & purificação , Plantas/química , Saponinas/isolamento & purificação , Sequência de Carboidratos , Flavonoides/química , Espectroscopia de Ressonância Magnética , Dados de Sequência Molecular , Saponinas/química
11.
J Nat Prod ; 56(9): 1605-8, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8254354

RESUMO

Two aristolochic acids [2 and 3] and a flavonol glycoside 1 have been isolated from Aristolochia rigida (Aristolochiaceae). Aristolochic acid IV [2], the most abundant constituent, has shown a weak direct mutagenic activity in the Ames test: this action seems to be inhibited, at least in part, by metabolic reactions.


Assuntos
Ácidos Aristolóquicos , Mutagênicos/toxicidade , Fenantrenos/toxicidade , Plantas Medicinais/química , Animais , Cromatografia em Camada Fina , Leucemia P388/tratamento farmacológico , Espectroscopia de Ressonância Magnética , Testes de Mutagenicidade , Fenantrenos/análise , Extratos Vegetais/análise , Salmonella typhimurium/genética , Somália
12.
J Nat Prod ; 56(2): 240-4, 1993 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8463796

RESUMO

Three triterpenoid saponins 1-3 of the oleanane series, containing one fucose and two glucose units, were isolated from the MeOH extract of the roots of Bupleurum fruticosum. Their structures were elucidated by means of fabms and a combination of homo- and heteronuclear 2D nmr techniques. Two of the three saponins are new.


Assuntos
Plantas Medicinais/química , Saponinas/análise , Triterpenos/análise , Espectroscopia de Ressonância Magnética , Medicina Tradicional Chinesa
13.
Planta Med ; 56(2): 230-1, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17221403

RESUMO

Umbelliferose has been isolated from the fruits of CACHRYS FERULACEA (L.) Calestani and the sugar sequence has been determined by NMR spectroscopic 2D-COLOC technique. The method of identification of the trisaccharide, which occurs only in the Umbelliferae family and may have a chemotaxonomic significance, is described and briefly discussed.

15.
Radiol Med ; 73(5): 434-7, 1987 May.
Artigo em Italiano | MEDLINE | ID: mdl-3296028

RESUMO

Urinary stress incontinence has been examined in 42 women with a standard radiographic technique, such as CCURG (colpocystourethrorectography) and echotomography. With these techniques 6 parameters have been established and measured both at rest and under Valsalva's maneuver. Stress incontinence has been diagnosed through variation of the normal values above physiological limits during the passage from rest to stress. In particular, reliability of echotomography in measuring the six parameters has been established and advantages and disadvantages have been evaluated in comparison with CCURG.


Assuntos
Ultrassonografia , Incontinência Urinária por Estresse/diagnóstico , Feminino , Humanos , Postura , Radiografia , Reto/diagnóstico por imagem , Uretra/diagnóstico por imagem , Bexiga Urinária/diagnóstico por imagem , Incontinência Urinária por Estresse/diagnóstico por imagem , Incontinência Urinária por Estresse/fisiopatologia , Vagina/diagnóstico por imagem , Manobra de Valsalva
17.
Br J Plast Surg ; 35(1): 88-91, 1982 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6461373

RESUMO

An experimental study in rats showed that the use of the alpha-receptor antagonist, thymoxamine could increase the blood supply to an ischaemic flap. Thymoxamine has a very short half-life, must be given frequently to be effective, but has the significant advantage that its action can be reversed by noradrenaline. When a flap is in trouble, alpha-receptor blockade by thymoxamine might help dramatically in its salvage.


Assuntos
Sobrevivência de Enxerto/efeitos dos fármacos , Moxisilita/farmacologia , Transplante de Pele , Animais , Masculino , Moxisilita/administração & dosagem , Período Pós-Operatório , Pré-Medicação , Ratos , Ratos Endogâmicos , Retalhos Cirúrgicos
18.
Minerva Chir ; 36(15-16): 1011-8, 1981.
Artigo em Italiano | MEDLINE | ID: mdl-7290414

RESUMO

After a review of the techniques of subcutaneous mastectomy and of reconstruction of the breast, the authors analyze the cause of the most common complications and suggest a method which is shown to prevent their occurrence: it is based on a wide exposure of the glands to be excised and of the following defect. A dermofat flap based inferiorly is interposed between the skin and the prosthesis. Complications have been very rare in a series of 35 cases and the results have been cosmetically very satisfactory. The method is therefore indicated in all the cases where some degree of ptosis is associated with the mammary condition.


Assuntos
Doenças Mamárias/cirurgia , Mama/cirurgia , Mastectomia , Cirurgia Plástica , Adulto , Feminino , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA