SE - Sistema Endócrino (Disfunção metabólica e doenças endócrinas)
Permanent URI for this community
Browse
Browsing SE - Sistema Endócrino (Disfunção metabólica e doenças endócrinas) by Issue Date
Now showing 1 - 10 of 15
Results Per Page
Sort Options
- HIPERTIROIDISMO E GRAVIDEZPublication . Castro, J.; Borges, F.Os autores descrevem as etiologias mais frequentes do hipertiroidismo que ocorre na gravidez e referem as alterações imunológicas que caracterizam a doença de Graves e a tolerância imunológica associada à gravidez. Referem o quadro clínico, o diagnóstico laboratorial e o tratamento a efectuar. Como o tratamento médico é o mais frequente, referem os antitiroideus de síntese, suas características e a opção mais conveniente para o tratamento durante a gravidez. The authors describe most common hyperthyroidism aetiologies that occur during pregnancy and also the immunity changes that define Graves disease and the immunity tolerance associated to pregnancy. They also refer the clinical pictur, laboratorial diagnosis and the treatment to be carried out. Medical treatment is mostly based on anti-thyroid drugs. Their characteristics and use during pregnancy are discussed.
- Urgências em Doenças Metabólicas - Formas de Apresentação TardiaPublication . Martins, E.
- Urgências em Doenças Metabólicas - Diagnóstico LaboratorialPublication . Cardoso, M.
- Defeitos da β-Oxidação Mitocondrial dos Ácidos Gordos - Artigo de RevisãoPublication . Sarmento, A.; Cardoso, M.; Barbo, C.; Martins, E.RESUMO Os defeitos da β-oxidação dos ácidos gordos constituem um grupo de doenças hereditárias do metabolismo que inclui 16 patologias distintas. O seu diagnóstico é por vezes difícil, visto que a maioria dos doentes está assintomática fora dos períodos de descompensação metabólica. O objectivo deste artigo é efectuar uma revisão do estado actual do conhecimento e apresentar de forma simplificada uma abordagem diagnóstica deste grupo de doenças. Clinicamente os defeitos da β-oxidação caracterizam-se pelo envolvimento de órgãos dependentes do metabolismo dos ácidos gordos para obtenção de energia, nomeadamente: coração, músculo esquelético e fígado. Há que exclui-las no contexto de síndrome de morte súbita do lactente e síndrome Reye like. As manifestações podem ser agudas e episódicas ou evoluir para formas crónicas (com cardiomiopatia hipertrófica e fraqueza muscular). A maioria manifesta- se durante o 1º ano de vida. Em termos laboratoriais é comum uma hipoglicemia hipocetótica e acidose metabólica. O diagnóstico é feito a partir do doseamento da carnitina, estudo do perfil das acilcarnitinas no plasma e estudo dos ácidos orgânicos e acilglicinas na urina. Os estudos genéticos e enzimáticos permitem confirmar o diagnóstico e são indispensáveis para a realização de um posterior diagnóstico pré-natal. O tratamento consiste em prevenir um jejum prolongado, favorecer o aporte de hidratos de carbono como fonte de energia e, dependendo do défice específicos, recorrer ao tratamento com carnitina, MCT e riboflavina. ABSTRACT Inborn defects in fatty acid β-oxidation are a complex group of diseases in which 16 different entities are recognized. These are genetic disorders, in which affected patients are often free of symptoms between episodes of acute decompensation, so clinical recognition may be difficult. The purpose of this article is to review this group of defects and, to present an approach to the appropriate evaluation. Clinically these diseases involve fatty acid β-oxidation energy dependent tissues like skeletal and cardiac muscle and liver. They must be considered in cases of sudden infant death syndrome and Reye like syndrome. Symptoms may be either acute and episodic or have a more chronic evolution (with hypertrophic cardiomiopaty and muscle weakness). Most of the times, they present in the first year of life. Laboratory features commonly present hipoketotic hypoglycemia and a metabolic acidosis. Carnitine measurement, study of acylcarnitines in blood, organic acids and acylglycines in urine are important to diagnosis. Currently genetic studies and enzyme activity measurement allow a precise diagnosis and better understanding of theses entities. The primary treatment is avoidance of prolonged fasting, restricting fatty acid uptake and increasing carbohydrate uptake. Depending on the type of the underlying metabolic disorder, treatment with carnitine, MCT or riboflavine may be indicated.
- Vómitos Cíclicos / Acidúria Glutárica tipo II - Caso ClínicoPublication . Sarmento, A.; Cardoso, M.; Teixeira, F.; Barbot, C.; Martins, E.RESUMO O síndrome de vómitos cíclicos caracteriza-se por episódios recorrentes de vómitos que persistem durante horas ou dias com intervalo de normalidade entre eles. O seu diagnóstico baseia-se na exclusão de outras patologias: alterações do aparelho gastrointestinal, lesão neurológica ocupante de espaço e doenças metabólicas. Apresenta-se o caso de uma adolescente de 13 anos, com má evolução staturoponderal, desenvolvimento psicomotor adequado e referência a vómitos recorrentes desde os 2 anos. Em alguns destes episódios documentou- se hipoglicemia, acidose metabólica, cetonúria marcada e aumento das transaminases hepáticas. O estudo metabólico efectuado aos 11 anos mostrou alterações na cromatografia dos ácidos orgânicos urinários com aumento do ácido β-hidroxiglutárico e acidúria dicarboxílica. Na repetição deste estudo estas alterações mantiveram-se. As hipóteses de diagnóstico incluíram défices da β-oxidação dos ácidos gordos, dos transportadores de electrões (acidúria glutárica tipo II), da cadeia mitocondrial e acidúria D2 ou L2-hidroxiglutárica. O perfil das acilcarnitinas plasmáticas e o estudo da cadeia respiratória no músculo revelaram-se normais. O doseamento do isómero D do ácido 2- hidroxiglutárico na urina, plasma e LCR mostrou-se elevado. Este último resultado seria compatível com acidúria D2- hidroxiglutárica, mas o estudo da β-oxidação em fibroblastos mostra diminuição da actividade do ETF (electron transfer flavoprotein), o que permitiu o diagnóstico definitivo de acidúria glutárica tipo II. Esta é uma doença rara, caracterizada não só por bloqueio da oxidação dos ácidos gordos, mas também por alterações na oxidação de aminoácidos de cadeia ramificada e degradação da lisina, triptofano e hidroxilisina. Tem clínica e gravidade variáveis. O caso referido representa um fenótipo de sintomatologia ligeira, essencialmente gastrointestinal, sem envolvimento major do sistema nervoso central, coração e músculo. ABSTRACT Cyclic vomiting syndrome is characterized by recurrent vomiting that last hours or days without symptoms between those episodes. The diagnosis is made when others disorders are excluded, like: abnormalities of gastrointestinal tract, neurological space-occupying lesions and metabolic disorders. We present a 13 years old girl with normal psychomotor development, weight loss and recurrent vomiting since two years old. During decompensation periods she had metabolic acidosis, severe ketonuria and increased transaminases levels in serum. Metabolic investigation performed at 11 years old exhibits changes on organic acid profiles, with marked increased excretion of D-2-hydroxyglutaric acid in urine and dicarboxylic aciduria. Forward analyses show the same. The differential diagnoses were disorders of β-oxidation, defects in pathway for transferring electrons, defects of the mitochondrial respiratory chain and D-2 or L-2-hydroxyglutaric aciduria. Analysis of plasma acylcarnitine profiles and study of mitochondrial respiratory chain in skeletal muscle were normal. The separation of D and L stereisomers of 2-hydroxyglutaric acid showed an increased of the D form in urine, plasma and CSF. The study of mitochondrial β-oxidation in fibroblasts showed a deficiency in ETF (electron transfer flavoprotein) and final diagnosis of Glutaric Aciduria type II. This is a rare disorder with defects not only in fatty acid oxidation, but also in the oxidation of branched-chain amino acids and degradation of lysine, tryptophan and hydroxylysine. Their clinical spectrum and prognosis are variable. The case reported show a phenotype with mild symptoms, mainly gastrointestinal symptoms, without major envelopment of central nervous system and skeletal muscle.
- A rat model of restrictive bariatric surgery with gastric bandingPublication . MONTEIRO, M.P.; MONTEIRO, J.D.; AGUAS, A.P.; CARDOSO, M.H.Obes Surg. 2006 Jan;16(1):48-51. A rat model of restrictive bariatric surgery with gastric banding. Monteiro MP, Monteiro JD, Aguas AP, Cardoso MH. Department of Anatomy of ICBAS (Abel Salazar Institute for the Biomedical Sciences), and Division of Endocrinology of Santo Antonio General Hospital, University of Porto, Porto, Portugal. mpmonteiro@icbas.up.pt Abstract BACKGROUND: Gastric banding is a well established weight reduction operation that is effective in the treatment of severe obesity. Its metabolic and endocrine mechanisms of action, however, remain unclear. The aim of this study was to establish a rat model of gastric banding that would replicate the procedure performed in human obese patients. METHODS: Male Wistar rats were submitted either to gastric banding (n=5) or sham gastric banding (n=4), and were followed for 21 days. Detailed description on how to perform gastric banding in rats are herein described. RESULTS: The Wistar rats submitted to gastric banding showed a decrease in weight gain and food intake when compared to sham-operated rats. The cumulative weight gain during the 21 days after the surgical procedure was 143+/-2.58 g for the gastric banded rats and 162+/-2.48 g for the sham-operated animals (P=0.001). The cumulative food intake was 329+/-0.53 g for the gastric banded rats and 380+/-15.22 g for the sham-operated animals, also statistically significant (P=0.025). CONCLUSION: A rat model to study gastric banding is described. This model can now be used for experimental investigation of biochemical and molecular mechanisms of weight loss resulting from this type of surgery. PMID: 16417758 [PubMed - indexed for MEDLINE]
- Rats submitted to gastric banding are leaner and show distinctive feeding patternsPublication . MONTEIRO, M.P.; MONTEIRO, J.D.; AGUAS, A.P.; CARDOSO, M.H.Obes Surg. 2006 May;16(5):597-602. Rats submitted to gastric banding are leaner and show distinctive feeding patterns. Monteiro MP, Monteiro JD, Aguas AP, Cardoso MH. Department of Anatomy, Unit for Multidisciplinary Biomedical Research, Abel Salazar Institute for the Biomedical Sciences, University of Porto, 4099-003 Porto, Portugal. mpmonteiro@icbas.up.pt Abstract BACKGROUND: Bariatric surgery is expanding to meet the global epidemic of morbid obesity, because this surgery is successful in achieving sustained weight loss. After having recently established a rat model of gastric banding, our aim now was to investigate the relative fat mass content and the feeding patterns of gastric banded rats. METHODS: Two groups of Wistar rats, submitted either to gastric banding or to sham surgery, were followed-up for 26 days regarding weight, daily food intake and feeding patterns both under resting conditions and when refed after fasting. Weight of the epididymal fat pad was used as a measure to evaluate changes in white adipose tissue in the rats. RESULTS: 10 days after surgery and thereafter, rats submitted to gastric banding showed the same daily food intake that was observed in sham-operated rats. Nevertheless, gastric banded rats kept lower body weights and were leaner than controls. These differences were associated with distinctive feeding patterns, both under resting conditions and when refed after fasting, suggesting that gastric banded rats present a significant increase in feeding frequency when compared with controls. CONCLUSION: This data is the first experimental evidence that an increase in feeding frequency is associated with weight loss after gastric banding, even if there is no decrease in total energy intake. Thus, medical advice on the advantages of fractionating daily caloric intake into multiple meals is further supported by the herein new information obtained in an animal model of gastric banding.
- SISTEMA RENINA-ANGIOTENSINA-ALDOSTERONA E sua Modulação FarmacológicaPublication . Giestas, A.; Palma, I.; Ramos, M:O sistema-renina-angiotensina-aldosterona (SRAA) é um sistema neuroendócrino complexo responsável pela modulação do equilíbrio hidroelectrolítico e regulação da pressão arterial. Através das suas múltiplas interacções contribui para a protecção do tecido endotelial, cardíaco, cerebral e renal. Adicionalmente, regula ainda a resposta do endotélio à inflamação e lesão. A sua activação crónica/desregulação induz hipertensão e perpetuação de uma cascata pró-inflamatória, pró-trombótica e aterogénica, que está na base da lesão de vários órgãos-alvo (coração, cérebro, rim, endotélio). Consequentemente, o SRAA constitui um alvo terapêutico importante nestas situações. O artigo aborda a fisiologia, patofisiologia e mecanismos de modulação farmacológica do SRAA. The renin-angiotensin-aldosterone system (RAAS) is a neuroendocrine complex system that regulates the modulation of salt and water homeostasis, and regulation of blood pressure. Through its multiple interactions it protects the endothelium, heart, brain and kidney. In addition, the RAAS regulates the vascular response to injury and inflammation. Chronic activation/dysregulation of the RAAS leads to hypertension and perpetuates a cascade of proinflammatory, prothrombotic and atherogenic effects associated with endorgan damage (heart, brain, kidney, endothelium). Consequently, the RAAS is an important therapeutic target in these situations. This article presents an overview of physiology, pathophysiology and pharmacologic modulation of the RAAS.
- SÍNDROME METABÓLICA NA GRAVIDEZ COMO FACTOR PREDITIVO DE OUTCOMES OBSTÉTRICOS E NEONATAIS ADVERSOSPublication . Teixeira, C.; Dores, J.O reconhecimento da Síndrome Metabólica (SM) durante a gravidez poderá ajudar a identificar um conjunto de mulheres que não só terão um risco aumentado para desenvolver complicações cardiovasculares e metabólicas mais tardiamente na vida, mas também, potencialmente, estarão em risco de desenvolver uma patologia relacionada com a gravidez. A implementação do rastreio da SM, na segunda metade da gravidez, poderá permitir identificar grávidas de alto risco e definir estratégias de intervenção adequadas. Este trabalho teve como objectivos (i) Determinar a prevalência de SM em gestações normais e complicadas; (ii) Avaliar o impacto do diagnóstico de SM na ocorrência de outcomes obstétricos e neonatais adversos.
- Non-Transferrin-Bound Iron (NTBI) Uptake by T Lymphocytes: Evidence for the Selective Acquisition of Oligomeric Ferric Citrate SpeciesPublication . Arezes, J.; Costa, M.; Vieira, I.; Dias, V.; Kong, X.; Fernandes, R.; Vos, M.; Carlsson, A.; Rikers, Y.; Porto, G.; Rangel, M.; Hider, R.; Pinto, J.Iron is an essential nutrient in several biological processes such as oxygen transport, DNA replication and erythropoiesis. Plasma iron normally circulates bound to transferrin. In iron overload disorders, however, iron concentrations exceed transferrin binding capacity and iron appears complexed with low molecular weight molecules, known as non-transferrin-bound iron (NTBI). NTBI is responsible for the toxicity associated with iron-overload pathologies but the mechanisms leading to NTBI uptake are not fully understood. Here we show for the first time that T lymphocytes are able to take up and accumulate NTBI in a manner that resembles that of hepatocytes. Moreover, we show that both hepatocytes and T lymphocytes take up the oligomeric Fe3Cit3 preferentially to other iron-citrate species, suggesting the existence of a selective NTBI carrier. These results provide a tool for the identification of the still elusive ferric-citrate cellular carrier and may also open a new pathway towards the design of more efficient iron chelators for the treatment of iron overload disorders.