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1.
Dement Geriatr Cogn Disord ; 29(6): 484-90, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20523046

RESUMO

BACKGROUND/AIMS: Mutations in the amyloid precursor protein gene were the first to be recognized as a cause of Alzheimer's disease (AD). METHODS: We describe 2 Italian families showing the missense mutation in exon 17 of the amyloid precursor protein gene on chromosome 21 (Val717Ile), known as London mutation. RESULTS: In 1 family, this mutation was responsible for AD in 3 out of 7 siblings and it is also present in a fourth sibling who has only shown signs of executive dysfunction so far. Two subjects of the other family with AD diagnosis were carriers of the same mutation. CONCLUSION: All AD subjects showed a cognitive profile characterized by early impairment in long-term memory, shifting abilities and affective symptoms beginning in the fifth decade of life.


Assuntos
Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Atenção/fisiologia , Transtornos Cognitivos/genética , Função Executiva/fisiologia , Idoso , Doença de Alzheimer/complicações , Doença de Alzheimer/patologia , Cromossomos Humanos Par 21/genética , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Diagnóstico Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Linhagem
2.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2270-2273, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018460

RESUMO

Iron plays important roles in healthy brain but altered homeostasis and concentration have been correlated to aging and neurodegenerative diseases. Iron enters the central nervous system by crossing the brain barrier systems: the Blood- Brain Barrier separating blood and brain and the Blood-Cerebrospinal Fluid Barrier (BCSFB) between blood and CSF, which is in contact with the brain by far less selective barriers. Herein, we develop a two-compartmental model for the BCSFB, based on first-order ordinary differential equations, performing numerical simulations and sensitivity analysis. Furthermore, as input parameters of the model, experimental data from patients affected by Alzheimer's disease, frontotemporal dementia, mild cognitive impairment and matched neurological controls were used, with the aim of investigating the differences between physiological and pathological conditions in the regulation of iron passage between blood and CSF which can be possibly targeted by therapy.


Assuntos
Doenças Neurodegenerativas , Barreira Hematoencefálica , Encéfalo , Humanos , Ferro , Modelos Teóricos
3.
Ann Oncol ; 20(2): 213-26, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18842614

RESUMO

The epidermal growth factor receptor (EGFr) is one of the most studied molecules as a target for cancer therapy. Over these last few years, several studies attempting to identify predictive biomarkers of treatment response, such as the receptor status or other molecules related to the downstream signalling pathway, have been conducted. However, from a clinical point of view, the information obtained from ex vivo analyses still has various limitations that may be overcome by the combination with molecular imaging technologies which may provide a noninvasive, global, in vivo evaluation of the molecular tumour background. The aim of this review is to report the preclinical results of all positron emission tomography (PET) tracers synthesized until now for in vivo detection of EGFr in cancer. Two classes of PET compounds have been developed: labelled small molecules such as tyrosine kinase inhibitors and labelled monoclonal antibodies. The in vitro and in vivo results of these PET tracers are very different depending on the chemical properties, positron emission radionuclide, or animal models. As a consequence, various critical questions are still open, and the implications of a translation in the clinical setting for EGFr imaging in cancer patients is discussed.


Assuntos
Receptores ErbB/análise , Neoplasias/diagnóstico por imagem , Neoplasias/enzimologia , Tomografia por Emissão de Pósitrons/métodos , Animais , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais/uso terapêutico , Linhagem Celular Tumoral , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Radioisótopos do Iodo , Células K562 , Camundongos , Inibidores de Proteínas Quinases/farmacologia , Cintilografia , Ratos , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Cancer Treat Rev ; 34(2): 103-21, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18055120

RESUMO

In the last ten years, the development of several novel targeted drugs and the refinement of state of the art technologies such as the genomics and proteomics and their introduction to clinical practice have revolutionized the management of patients affected by cancer. However, everyday practice points out several clinical questions: the difficulty of response assessment to new drugs especially using standard RECIST criteria that do not provide information on biological, vascular or metabolic variations; the inadequate selection of patients who are likely to benefit from a targeted therapy excluding those with breast cancer and gastrointestinal stromal tumours; the need to know the global biological background of diseases especially in metastatic setting using repeatable non-invasive procedures. Molecular imaging could provide information on in vivo distribution of biological markers in response to targeted therapy and could improve the selection of patients before therapies. The aim of this review is to analyze the current role of conventional and innovative positron emission tomography (PET) radiotracers in clinical practice and to explore the promising perspectives of molecular imaging in cancer research.


Assuntos
Neoplasias/diagnóstico , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Avaliação da Tecnologia Biomédica , Diagnóstico por Imagem/métodos , Sistemas de Liberação de Medicamentos , Expressão Gênica , Humanos , Neoplasias/terapia , Neovascularização Patológica/diagnóstico , Resultado do Tratamento
5.
Int J Oncol ; 33(3): 443-52, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18695872

RESUMO

The widespread use of several new non-cytotoxic drugs and the significant improvements in functional imaging highlights a number of difficulties in monitoring, interpreting and predicting treatment response in clinical practice. Certain guidelines for disease assessment after therapy are already available: the traditional Response Evaluation Criteria in Solid Tumours guidelines based on tumour size variations using conventional imaging technologies, the recent combined method developed by Choi and colleagues in gastrointestinal stromal tumour treated with tyrosine kinase inhibitors based on tumour density variations using computed tomography (CT), and the European Organization for Research and Treatment of Cancer criteria based on tumour glucose metabolism variations using fluorodeoxyglucose (FDG) positron emission tomography (PET). At the moment combined PET/CT response criteria are still not available. A number of new PET compounds other than FDG are also currently being developed to visualize specific cellular and molecular tumour pathways but their role in assessment and prediction of cancer treatment response has not yet been thoroughly investigated in a large series. However, in clinical practice many oncologists treat cancer patients with targeted therapies or chemotherapy and evaluate the response using conventional or functional imaging without appropriate and standardized guidelines. The aim of this study was to present a selection of clinical cases that illustrate the usefulness of new PET tracers and efficacy evaluation of new drugs. In the era of molecular imaging and molecular therapies, these cases highlight the urgency to develop new criteria for treatment assessment and the exigency of correctly interpreting the biological information obtained from new technologies, and introduce new concepts that require further investigation in clinical trials.


Assuntos
Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Idoso , Antineoplásicos/uso terapêutico , Radioisótopos de Carbono , Colina , Ensaios Clínicos como Assunto , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Metionina , Pessoa de Meia-Idade , Neoplasias/tratamento farmacológico , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X
6.
Appl Radiat Isot ; 66(8): 1091-6, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18226535

RESUMO

Somatostatin receptors 1-5 are over expressed in neuroendocrine tumours (NETs). 68Ga-labelled [1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid]-1-Nal3-Octreotide (DOTA NOC), a recent synthesized somatostatin analogue, shows high affinity for those receptors. Herein, modifications of a commercial module for the labelling of DOTA NOC with 68Ga, as well as the assessment of time course of the radiochemical purity variation are described. The evaluation of radiochemical stability was done by two different chromatographic methods: reversed-phase radio HPLC and fast TLC analysis. Labelled compound has been found radiochemically stable within 3h from the end of labelling (EOL) and radiochemical purity was always higher than 99%. After 73 labelling sessions the system showed great reproducibility and high radiochemical yield.


Assuntos
Gadolínio/química , Compostos Organometálicos/síntese química , Compostos Radiofarmacêuticos/síntese química , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Marcação por Isótopo/métodos , Compostos Organometálicos/química , Controle de Qualidade , Compostos Radiofarmacêuticos/química , Reprodutibilidade dos Testes
7.
Musculoskelet Surg ; 99(2): 127-32, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25904348

RESUMO

BACKGROUND AND PURPOSE: Irreparable rotator cuff tears are a common cause of pain in adult population, requiring in many cases a surgical treatment. Possible alternatives are debridement, partial repair, muscle transfers and joint replacement. We evaluated two groups of patients with irreparable rotator cuff tear treated surgically: one group received an arthroscopic-assisted latissimus dorsi tendon transfer (LDTT), and the other an arthroscopic rotator cuff partial repair. Aim of our study was to compare clinical results and quality of life in two groups of patients with massive irreparable rotator cuff tear: one receiving an arthroscopic LDTT and the other receiving an arthroscopic rotator cuff partial repair. METHODS: Forty patients were assigned to two groups: 20 patients to group TT treated with LDTT and 20 patients to group PR treated with a partial repair. The average follow-up duration was 2.8 years (1-5, SD 3). Pre- and postoperative modified UCLA shoulder score, ROM, measurement of the strength and the rotator cuff quality of life (RC-QOL) were used to asses the outcome. RESULTS: LDTT showed significative improvements when compared to partial repair in UCLA score results, strength and RC-QOL questionnaire. No differences were found between the groups in pain relief. CONCLUSION: Both techniques are effective in reducing patients' symptoms. We believe that in younger, high-demanding patients with no or mild osteoarthritis, the LDTT represents a valid treatment option with better modified UCLA score improvement and strength at our follow-up.


Assuntos
Lesões do Manguito Rotador/cirurgia , Músculos Superficiais do Dorso/transplante , Fatores Etários , Idoso , Artralgia/cirurgia , Artroscopia/métodos , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Qualidade de Vida , Ruptura/cirurgia , Transferência Tendinosa/métodos , Fatores de Tempo , Resultado do Tratamento
8.
Infect Genet Evol ; 32: 231-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25801607

RESUMO

Worldwide, more than 170 million people are chronically infected with the hepatitis C virus (HCV) and every year die more than 350,000 people from HCV-related liver diseases. Recently, HCV was reclassified into seven major genotypes and 67 subtypes. Some subtypes as 1a, 1b and 3a, have become epidemic as a result of the new parenteral transmission routes and are responsible for most HCV infections in Western countries. HCV 1a subtype have been sub-categorized into two separate sub clades. Recent studies based on the analysis of NS5B genome region, reveal that HCV epidemics in Argentina and Brazil are characterized by multiple introductions events of subtypes 1a, 1b and 3a, followed by subsequent local dispersion. There is no data about HCV genotypes circulating in Uruguay and their evolutionary and demographic history. To this end, a total of 153 HCV NS5B gene sequences were obtained from Uruguayan patients between 2005 and 2011. 86 (56%) sequences grouped with subtype 1a, 40 (26%) with subtype 3a and 27 (18%) with subtype 1b. Furthermore, subtype 1a sequences were distributed among both clades, 1 (n=62, 72%) and 2 (n=24, 28%). Four local HCV clades were found: UY-1a(I), UY-1a(II), UY-1a(III) and UY-3a; comprising a 39% of all HCV viruses analyzed in this study. HCV epidemic in Uruguay has been driving by multiple introductions of subtypes 1a, 1b and 3a and by local dissemination of a few country-specific strains. The evolutionary and demographic history of the major Uruguayan HCV clade UY-1a(I) was reconstructed under two different molecular clock rate models and displayed an epidemic history characterized by an initial phase of rapid expansion followed by a more recent reduction of growth rate since 2000-2005. This is the first comprehensive study about the molecular epidemiology and epidemic history of HCV in Uruguay.


Assuntos
Genoma Viral , Genótipo , Hepacivirus/genética , Hepatite C/virologia , Argentina/epidemiologia , Brasil/epidemiologia , Evolução Molecular , Hepacivirus/classificação , Hepacivirus/isolamento & purificação , Hepatite C/epidemiologia , Humanos , Epidemiologia Molecular , Filogenia , RNA Viral/genética , Análise de Sequência de RNA , Uruguai
9.
Hypertension ; 29(1 Pt 1): 105-10, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9039088

RESUMO

To investigate the involvement of endogenous opioids in acute increases in blood pressure and their functional relationship with atrial natriuretic factor and endothelin-1, we assessed plasma levels of beta-endorphin, met-enkephalin, dynorphin B, catecholamines, atrial natriuretic factor, and endothelin-1 before and after administration of the opioid antagonist naloxone hydrochloride (8 mg i.v.) in 28 hypertensive patients with a stress-induced acute increase in blood pressure. Ten patients with established mild or moderate essential hypertension and 10 normotensive subjects served as control groups. Opioids, atrial natriuretic factor, and endothelin-I were radioimmunoassayed after chromatographic preextraction; catecholamines were determined by high-performance liquid chromatography with electrochemical detection. Patients with an acute increase in blood pressure (systolic, 203.2 +/- 2.2 mm Hg; diastolic, 108.4 +/- 1.3) had plasma opioid, catecholamine, and atrial natriuretic factor levels significantly (P < .01) higher than hypertensive control patients (systolic pressure, 176.4 +/- 1.0 mm Hg; diastolic, 100.0 +/- 1.4), who had a hormonal pattern similar to that of normotensive subjects (systolic pressure, 123.2 +/- 1.5 mm Hg; diastolic, 75.0 +/- 2.0). Endothelin-1 did not differ in any group. In patients with an acute increase in blood pressure, naloxone significantly (P < .01) reduced blood pressure, heart rate, opioids, catecholamines, and atrial natriuretic factor 10 minutes after administration. Naloxone effects on blood pressure, heart rate, opioids, and catecholamines wore off within 20 minutes. In control groups, naloxone failed to modify any of the considered parameters. Our findings suggest that pressor effects of opioid peptides mediated by the autonomic nervous system during stress-induced acute episodes of blood pressure increase in hypertensive patients.


Assuntos
Pressão Sanguínea/fisiologia , Hipertensão/fisiopatologia , Peptídeos Opioides/fisiologia , Fator Natriurético Atrial/antagonistas & inibidores , Fator Natriurético Atrial/sangue , Fator Natriurético Atrial/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Dinorfinas/antagonistas & inibidores , Dinorfinas/sangue , Dinorfinas/fisiologia , Endorfinas/antagonistas & inibidores , Endorfinas/sangue , Endorfinas/fisiologia , Endotelina-1/antagonistas & inibidores , Endotelina-1/sangue , Endotelina-1/fisiologia , Encefalina Metionina/antagonistas & inibidores , Encefalina Metionina/sangue , Encefalina Metionina/fisiologia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Hipertensão/sangue , Hipertensão/etiologia , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Naloxona/administração & dosagem , Naloxona/farmacologia , Antagonistas de Entorpecentes/administração & dosagem , Antagonistas de Entorpecentes/farmacologia , Norepinefrina/antagonistas & inibidores , Norepinefrina/sangue , Norepinefrina/fisiologia , Peptídeos Opioides/antagonistas & inibidores , Peptídeos Opioides/sangue , Estresse Fisiológico/complicações , Estresse Psicológico/complicações , beta-Endorfina/antagonistas & inibidores , beta-Endorfina/sangue , beta-Endorfina/fisiologia
10.
J Clin Endocrinol Metab ; 86(1): 337-43, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11232021

RESUMO

Although the role that LH plays in folliculogenesis is still controversial, recent evidence points toward facilitatory actions of LH activity in ovulation induction. Thus, we compared the response to either highly purified FSH (75 IU FSH/ampoule; group A, 25 subjects) or human menopausal gonadotropin (75 IU FSH and 75 IU LH/ampoule; group B, 25 subjects) in normoovulatory GnRH agonist-suppressed women, candidates for intrauterine insemination. A fixed regimen of 2 daily ampoules of highly purified FSH or human menopausal gonadotropin was administered in the initial 14 days of treatment; menotropin dose adjustments were allowed thereafter. Treatment was monitored with daily blood samples for the measurement of LH, FSH, 17beta-estradiol (E(2)), progesterone, testosterone, hCG, inhibin A, and inhibin B, and transvaginal pelvic ultrasound was performed at 2-day intervals. Although preovulatory E(2) levels were similar, both the duration of treatment (16.1 +/- 0.8 vs. 12.6 +/- 0.5 days; P< 0.005) and the per cycle menotropin dose (33.6 +/- 2.4 vs. 23.6 +/- 1.1 ampoules; P < 0.005) were lower in group B. In the initial 14 treatment days the area under the curve of FSH, progesterone, testosterone, inhibin A, and inhibin B did not differ between the 2 groups, whereas LH, hCG, and E(2) areas under the curve were higher in group B. The occurrence of small follicles (<10 mm) and the inhibin B/A ratio in the late follicular phase were significantly reduced in group B. A nonsignificant trend toward a higher multiple gestation rate was present in group A (60% vs. 17%). We conclude that ovulation induction with LH activity-containing menotropins is associated with 1) shorter treatment duration, 2) lower menotropin consumption, and 3) reduced development of small ovarian follicles. These features can be exploited to develop regimens that optimize treatment outcome, lower costs, and reduce occurrence of complications such as multiple gestation and ovarian hyperstimulation.


Assuntos
Hormônio Foliculoestimulante/administração & dosagem , Hormônio Luteinizante/administração & dosagem , Menotropinas/administração & dosagem , Folículo Ovariano/fisiologia , Indução da Ovulação , Adulto , Feminino , Humanos , Infertilidade/tratamento farmacológico , Hormônio Luteinizante/fisiologia , Menotropinas/fisiologia , Folículo Ovariano/efeitos dos fármacos , Ovulação/efeitos dos fármacos , Ovulação/fisiologia , Gravidez , Resultado do Tratamento , Pamoato de Triptorrelina/administração & dosagem
11.
J Clin Endocrinol Metab ; 80(11): 3346-50, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7593449

RESUMO

It has been shown that in vitro calcium channel blockers may regulate insulin secretion, and in vivo studies have demonstrated that they can reduce the degree of hyperinsulinemia and ameliorate the insulin-resistant state in subjects (particularly men) with obesity and hypertension. It is also commonly accepted that hyperinsulinemia may be an important factor responsible for the development of hyperandrogenism in obese women with polycystic ovarian syndrome (PCOS). We, therefore, investigated whether the administration of nitrendipine, a widely used calcium channel blocker, may improve both insulin levels and hyperandrogenism in a group of seven insulin-resistant hyperinsulinemic women with obesity and PCOS. They were treated for 7-8 days with oral nitrendipine (10 mg, twice daily) or placebo using a double blind, cross-over design. Before and after treatment, blood samples were obtained for androgen and sex hormone-binding globulin determinations, and an oral glucose tolerance test was performed, measuring glucose and insulin. Both nitrendipine and placebo failed to decrease basal and stimulated insulin levels. Moreover, no significant variations in testosterone, dehydroepiandrosterone sulfate, or sex hormone-binding globulin concentrations were observed after either treatment. Therefore, these data fail to support previous suggestions that calcium channel blockers may play a role in the treatment of hyperandrogenism and hyperinsulinemia in obese women with PCOS.


Assuntos
Androgênios/sangue , Bloqueadores dos Canais de Cálcio/uso terapêutico , Insulina/sangue , Nitrendipino/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , Globulina de Ligação a Hormônio Sexual/metabolismo , Adulto , Glicemia/análise , Pressão Sanguínea , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/fisiopatologia , Resultado do Tratamento
12.
J Clin Endocrinol Metab ; 83(10): 3643-6, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9768678

RESUMO

We evaluated the circulating levels of GH, insulin-like growth factor I (IGF-I), GH-binding protein (GHBP), and IGF-binding protein-3 (IGFBP-3) before L-T4 therapy in 19 infants with congenital hypothyroidism (CH), aged 12-29 days, diagnosed by neonatal screening and in a group of age- and sex-matched control infants. The same parameters were reevaluated after several months of treatment. Serum GHBP was measured by the high performance liquid chromatography-gel filtration method; serum GH, IGF-I, and IGFBP-3 levels were determined by commercial kits. The hypothyroid patients, before beginning therapy, presented significantly lower GHBP values than controls (P < 0.0001); during treatment, these values increased significantly; however, after 6 months they were still significantly lower than control values (P < 0.01). The pretreatment levels of GH were not significantly different from control values; after 1 month of treatment, GH did not show the decrease observed in controls and, therefore, was significantly higher (P < 0.01). The pretreatment levels of IGF-I were not significantly different from control values, but were lower in patients with severe than in those with mild hypothyroidism. They decreased at about 4 months of life and became significantly lower than control values at about 7 months of age (P < 0.05). In conclusion, it may be hypothesized that the condition of CH induces a change in GHBP expression, perhaps beginning in fetal life. The intrauterine production of IGF-I seems to be independent of the levels of GHBP and partially affected by fetal thyroid function.


Assuntos
Proteínas de Transporte/sangue , Hipotireoidismo Congênito , Hipotireoidismo/sangue , Feminino , Hormônio do Crescimento Humano/sangue , Humanos , Hipotireoidismo/tratamento farmacológico , Recém-Nascido , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/análise , Masculino , Valores de Referência , Hormônios Tireóideos/sangue , Tiroxina/uso terapêutico
13.
J Clin Endocrinol Metab ; 80(2): 654-8, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7852532

RESUMO

There are no studies in vivo on the effects of insulin on androgens and sex hormone-binding globulin (SHBG) in men. We, therefore, investigated the effects of insulin suppression on testosterone and SHBG in two groups of eight nondiabetic adult obese men and six healthy normal weight men who underwent diazoxide treatment (100 mg, three times daily) for 7 days. Blood samples for hormone determination were obtained before the subjects had been selected for the study, immediately before diazoxide administration, and on the last day of treatment. A 24-h oral glucose tolerance test was also performed for glucose, insulin, and C-peptide determinations before and on the last day of treatment. Only one subject experienced significant side-effects, and no significant changes in mean body weight were found during the treatment. Diazoxide administration worsened glucose tolerance in several subjects and reduced fasting and glucose-stimulated insulin levels by approximately 50% in both control and obese subjects. No significant difference was present between historical and pretreatment hormone values in either group. Moreover, there were no differences in pretreatment gonadotropin and SHBG concentrations between the two groups, whereas testosterone (free and total) levels were lower in the obese than in the control subjects. After diazoxide administration, testosterone (free and total) decreased slightly, but significantly, whereas LH and SHBG significantly increased in both groups. Diazoxide treatment increased estradiol levels in controls, but not in obese men. In conclusion, these results indicate that in vivo, insulin is capable of stimulating testosterone production and, simultaneously, of inhibiting SHBG concentrations in both normal weight and obese men.


Assuntos
Peso Corporal , Insulina/fisiologia , Obesidade/sangue , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue , Adulto , Diazóxido/farmacologia , Teste de Tolerância a Glucose , Hormônios Esteroides Gonadais/sangue , Gonadotropinas/sangue , Humanos , Antagonistas da Insulina/farmacologia , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Valores de Referência
14.
Am J Clin Nutr ; 71(1 Suppl): 339S-42S, 2000 01.
Artigo em Inglês | MEDLINE | ID: mdl-10617993

RESUMO

The rationale for supplementation with n-3 fatty acids to promote the health of the gastrointestinal tract lies in the antiinflammatory effects of these lipid compounds. The first evidence of the importance of dietary intake of n-3 polyunsaturated fatty acids was derived from epidemiologic observations of the low incidence of inflammatory bowel disease in Eskimos. The aim of this paper was to briefly review the literature on the use of n-3 fatty acids in inflammatory bowel disease (ulcerative colitis and Crohn disease), the results of which are controversial. The discrepancies between studies may reside in the different study designs used as well as in the various formulations and dosages used, some of which may lead to a high incidence of side effects. Choosing a formulation that lowers the incidence of side effects, selecting patients carefully, and paying strict attention to experimental design are critical when investigating further the therapeutic potential of these lipids in inflammatory bowel disease.


Assuntos
Colite Ulcerativa/dietoterapia , Doença de Crohn/dietoterapia , Ácidos Graxos Ômega-3/uso terapêutico , Gorduras Insaturadas na Dieta/uso terapêutico , Ácidos Graxos Ômega-3/administração & dosagem , Óleos de Peixe/uso terapêutico , Humanos , Azeite de Oliva , Cooperação do Paciente , Óleos de Plantas , Recidiva
15.
Am J Med ; 109(8): 621-7, 2000 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-11099681

RESUMO

PURPOSE: To investigate the effects of hypoxemia, hypercapnia, and cardiovascular hormones (norepinephrine, endothelin-1, and atrial natriuretic factor) on blood pressure during acute respiratory failure. PATIENTS AND METHODS: Patients with chronic obstructive pulmonary disease and acute respiratory failure were divided into four groups of 10 patients each: hypoxemia-normocapnia, hypoxemia-hypercapnia, hypoxemia-hypocapnia, and normoxemia-hypercapnia. Plasma norepinephrine levels were determined by high-performance liquid chromatography with electrochemical detection. Plasma endothelin-1 and atrial natriuretic factor levels were radioimmunoassayed after chromatographic preextraction. RESULTS: Systolic blood pressure and cardiovascular hormone levels were greater in patients with hypercapnia (whether or not they also had hypoxemia) than in those with normocapnia and hypoxemia. For example, in patients with hypercapnia and normoxemia, the mean (+/- SD) systolic blood pressure was 183+/-31 mm Hg and the mean norepinephrine level was 494+/-107 pg/mL, as compared with 150+/- 6 mm Hg and 243+/-58 pg/mL in those with normocapnia and hypoxemia (both P<0.05). Similar results were seen for endothelin-1 and atrial natriuretic factor levels, and for the comparisons of hypoxemic patients who were hypercapnic with those who were normocapnic. CONCLUSIONS: These results suggest that blood carbon dioxide levels, rather than oxygen levels, are responsible for hypertension during acute respiratory failure, perhaps as a result of enhanced sympatho-adrenergic activity.


Assuntos
Dióxido de Carbono/sangue , Hipertensão/sangue , Hipertensão/etiologia , Pneumopatias Obstrutivas/complicações , Oxigênio/sangue , Insuficiência Respiratória/complicações , Doença Aguda , Adulto , Idoso , Fator Natriurético Atrial/sangue , Pressão Sanguínea , Endotelina-1/sangue , Feminino , Frequência Cardíaca , Humanos , Hipercapnia/sangue , Hipocapnia/sangue , Hipóxia/sangue , Pneumopatias Obstrutivas/sangue , Masculino , Pessoa de Meia-Idade , Norepinefrina/sangue , Insuficiência Respiratória/sangue , Índice de Gravidade de Doença
16.
J Hypertens ; 14(4): 509-17, 1996 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-8761902

RESUMO

OBJECTIVES: To identify factors predisposing subjects to the development of stable hypertension and to estimate their relative importance in 70 young patients with borderline hypertension monitored for 10 years. DESIGN: Longitudinal evaluation of the incidence of stable hypertension [diastolic blood pressure (DBP) > 95 mmHg]. METHODS: Patients were examined at baseline by determination of resting blood pressure, intracellular sodium level and individual pressor response to mental arithmetic and to intravenous saline loading. They were re-examined after 10 years to assess the prevalence of established hypertension and the importance of some prognostic variables identified prospectively (age, sex, intracellular sodium level, baseline blood pressure, pressor response to stress and acute salt-sensitivity). RESULTS: The prevalence of sustained hypertension (DBP > 95 mmHg) was 35.8% after 10 years of follow-up study. Subjects developing hypertension were older (26.9 +/- 1.3 versus 21.0 +/- 1.8 years) and showed a higher percentage of family history of hypertension (92 versus 64%) and of acute salt-sensitivity (72 versus 53%). The pressor response to mental arithmetic was greater in patients who developed hypertension (systolic blood pressure 26.9 +/- 1 versus 22.7 +/- 0.9 mmHg, P = 0.005 DBP = 16.6 +/- 0.8 versus 13.1 +/- 0.7 mmHg, P = 0.005), who also showed higher levels of intracellular sodium (30.7 +/- 0.6 versus 27.3 +/- 0.5 mmol/kg, P = 0.001). The same variables were found to be related to the development of hypertension in a multivariate analysis and the concomitant presence of 4-5 risk factors was associated with a reasonable predictive power for the identification of patients at high risk (sensitivity 72%, specificity 67%, predictive accuracy 76%). CONCLUSIONS: The present study demonstrates that borderline hypertensives at high risk of stable hypertension can be identified by the concomitant evaluation of some clinical and cellular characteristics directly related to long-term development of high blood pressure.


Assuntos
Hipertensão/etiologia , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino , Fatores de Risco
17.
J Hypertens ; 12(11): 1285-90, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7868876

RESUMO

OBJECTIVE: To investigate the effects of the endogenous opioid system on plasma atrial natriuretic factor (ANF) levels during sympathetic hyperactivity. DESIGN: We studied the young normotensive offspring of parents who both had essential hypertension, who are characterized by a hyperactive sympathetic nervous system. METHODS: We assessed plasma beta-endorphin, met-enkephalin, dynorphin B, ANF and noradrenaline levels, blood pressure and heart rate values in eight normotensive offspring and in 10 young normotensive subjects with no family history of hypertension (controls) at rest and during two exercise tests: the first test performed with the infusion of placebo (1.5 ml/min saline) and the second test with the infusion of an opioid antagonist (9.5 micrograms/kg per min naloxone hydrochloride). ANF and opioids were radioimmunoassayed after chromatographic pre-extraction. RESULTS: At rest plasma met-enkephalin, dynorphin B, ANF and noradrenaline values in the normotensive offspring were significantly higher than in the controls. Exercise with placebo significantly raised all hormonal and haemodynamic parameters in the two groups. This increase was significantly higher in the normotensive offspring than in the controls. Naloxone did not modify any parameter in either group at rest, but it enhanced further the rise in plasma noradrenaline levels induced by exercise in both groups. A similar effect of naloxone during exercise was observed for plasma ANF levels in the normotensive offspring. CONCLUSIONS: Our findings show that plasma met-enkephalin, dynorphin B, ANF and noradrenaline levels at rest and during exercise are higher in normotensive offspring than in controls. The effects of naloxone indicate that in normotensive offspring at rest the opioid system does not affect ANF release, whereas during exercise it attenuates ANF hypersecretion, possibly by reducing noradrenaline release.


Assuntos
Fator Natriurético Atrial/sangue , Hipertensão/sangue , Naloxona/farmacologia , Peptídeos Opioides/sangue , Esforço Físico , Adulto , Suscetibilidade a Doenças , Dinorfinas/sangue , Endorfinas/sangue , Encefalina Metionina/sangue , Teste de Esforço , Feminino , Hemodinâmica/efeitos dos fármacos , Humanos , Hipertensão/genética , Masculino , Norepinefrina/sangue , Radioimunoensaio , beta-Endorfina/sangue
18.
Am J Cardiol ; 66(5): 597-602, 1990 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-2144096

RESUMO

An increased venous tone responsible for changes in systemic hemodynamics has been described in borderline hypertensive patients along with the release, in response to intravenous sodium chloride, of an endogenous sodium ion/potassium ion adenosine triphosphatase (Na+/K+ ATPase) inhibitor with vasoconstrictive properties. The hemodynamic and humoral effects of a 2-hour intravenous saline infusion were studied in 25 borderline hypertensives characterized on the basis of their forearm venous distensibility (VV30) in normal (n = 15) and low (n = 10) VV30. VV30 was slightly reduced by saline in the entire hypertensive group (1.47 vs 1.36 ml/100 ml; p less than 0.05), whereas blood pressure and plasma Na+/K+ ATPase inhibitor were unchanged. Normal VV30 showed a sudden increase in plasma Na+/K+ ATPase inhibitor in response to saline associated with an increase in blood pressure, a forearm arterial and venous constriction, and a sluggish suppression in plasma renin activity, whereas low VV30 exhibited a completely opposite pattern. The changes in plasma Na+/K+ ATPase inhibitor inversely correlated to VV30 decreases in borderline hypertensives with normal VV30 (r = -0.49; p less than 0.05), whereas they did not in all hypertensive patients. Atrial natriuretic peptide response to saline infusion was delayed in normal VV30 and inversely related to the changes in Na/K+ ATPase inhibitory activity (r = -42; p less than 0.05) attained after 2 hours of infusion in the entire hypertensive population. Results of this study suggest the ability of acute volume expansion to reduce peripheral venous distensibility in borderline hypertensive patients.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Hipertensão/fisiopatologia , Volume Plasmático , Pressão Venosa , Adolescente , Adulto , Aldosterona/sangue , Fator Natriurético Atrial/metabolismo , Feminino , Antebraço , Hemodinâmica/fisiologia , Humanos , Masculino , Volume Plasmático/efeitos dos fármacos , Proteínas/metabolismo , ATPases Translocadoras de Prótons/antagonistas & inibidores , Renina/sangue , Cloreto de Sódio/administração & dosagem , Urina/análise , Vasodilatação/fisiologia , Proteína Inibidora de ATPase
19.
Am J Cardiol ; 65(5): 343-8, 1990 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-2137279

RESUMO

Rest and exercise hemodynamic and hormonal effects of nicorandil, a nicotinamide-nitrate vasodilator, were assessed in 9 patients with New York Heart Association class II or III congestive heart failure (CHF) and left ventricular ejection fraction less than or equal to 40%. Single oral doses of placebo and 40 and 60 mg of nicorandil were given in a double-blind, randomized trial. Hemodynamic measurements were assessed at rest, up to 8 hours after dose and at peak exercise performed on an upright cycloergometer 1 hour after the dose. Forearm blood flow and venous capacitance were measured by plethysmography 45 minutes after dose. Plasma noradrenaline and plasma renin activity were assessed 1 hour and 2 hours after dose, respectively. Data were analyzed by analysis of variance. Peak effects were observed between 30 and 60 minutes after dose. Mean blood pressure decreased from 86 +/- 7 mm Hg after placebo to 78 +/- 7 mm Hg after 40 mg (p less than 0.05) and to 78 +/- 7 mm Hg after 60 mg (p less than 0.05) of nicorandil. Mean pulmonary artery pressure decreased from 24 +/- 11 to 15 +/- 17 mm Hg (p less than 0.05) and to 17 +/- 7 mm Hg (p less than 0.05) and mean pulmonary wedge pressure decreased from 15 +/- 8 to 9 +/- 4 mm Hg (p less than 0.05) and to 10 +/- 5 mm Hg (p less than 0.05). The changes were significant up to 6 to 8 hours after both doses.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Insuficiência Cardíaca/tratamento farmacológico , Hemodinâmica/efeitos dos fármacos , Niacinamida/análogos & derivados , Vasodilatadores/uso terapêutico , Adulto , Método Duplo-Cego , Exercício Físico/fisiologia , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Niacinamida/uso terapêutico , Nicorandil , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Tempo
20.
Am J Cardiol ; 79(7): 957-9, 1997 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9104911

RESUMO

At peak exercise, plasma endothelin-1 concentration increases in patients with effort angina as well as thallium-201 radionuclide perfusion defects; the opposite occurs in patients with normal scans and in healthy volunteers. It is concluded that exercise-induced ischemia correlates with enhanced endothelin-1 production.


Assuntos
Angina Pectoris/sangue , Endotelina-1/sangue , Isquemia Miocárdica/sangue , Angina Pectoris/diagnóstico , Angina Pectoris/diagnóstico por imagem , Estudos de Casos e Controles , Teste de Esforço , Feminino , Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/diagnóstico , Isquemia Miocárdica/diagnóstico por imagem , Cintilografia , Radioisótopos de Tálio
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