RESUMO
Sequential cleavage of the precursor protein pre-pro-opiomelanocortin (POMC) generates the melanocortin peptides adrenocorticotrophin (ACTH), melanocyte-stimulating hormones (MSH) alpha, beta and gamma as well as the opioid-receptor ligand beta-endorphin. While a few cases of isolated ACTH deficiency have been reported (OMIM 201400), an inherited POMC defect has not been described so far. Recent studies in animal models elucidated a central role of alpha-MSH in the regulation of food intake by activation of the brain melanocortin-4-receptor (MC4-R; refs 3-5) and the linkage of human obesity to chromosome 2 in close proximity to the POMC locus, led to the proposal of an association of POMC with human obesity. The dual role of alpha-MSH in regulating food intake and influencing hair pigmentation predicts that the phenotype associated with a defect in POMC function would include obesity, alteration in pigmentation and ACTH deficiency. The observation of these symptoms in two probands prompted us to search for mutations within their POMC genes. Patient 1 was found to be a compound heterozygote for two mutations in exon 3 (G7013T, C7133delta) which interfere with appropriate synthesis of ACTH and alpha-MSH. Patient 2 was homozygous for a mutation in exon 2 (C3804A) which abolishes POMC translation. These findings represent the first examples of a genetic defect within the POMC gene and define a new monogenic endocrine disorder resulting in early-onset obesity, adrenal insufficiency and red hair pigmentation.
Assuntos
Insuficiência Adrenal/genética , Cor de Cabelo/genética , Mutação , Obesidade/genética , Pró-Opiomelanocortina/genética , Precursores de Proteínas/genética , Insuficiência Adrenal/complicações , Hormônio Adrenocorticotrópico/deficiência , Criança , Análise Mutacional de DNA , Éxons , Feminino , Mutação da Fase de Leitura , Humanos , Masculino , Obesidade/complicações , FenótipoRESUMO
Chronic pancreatitis (CP) is a continuing or relapsing inflammatory disease of the pancreas. In approximately one-third of all cases, no aetiological factor can be found, and these patients are classified as having idiopathic disease. Pathophysiologically, autodigestion and inflammation may be caused by either increased proteolytic activity or decreased protease inhibition. Several studies have demonstrated mutations in the cationic trypsinogen gene (PRSS1) in patients with hereditary or idiopathic CP. It is thought that these mutations result in increased trypsin activity within the pancreatic parenchyma. Most patients with idiopathic or hereditary CP, however, do not have mutations in PRSS1 (ref. 4). Here we analysed 96 unrelated children and adolescents with CP for mutations in the gene encoding the serine protease inhibitor, Kazal type 1 (SPINK1), a pancreatic trypsin inhibitor. We found mutations in 23% of the patients. In 18 patients, 6 of whom were homozygous, we detected a missense mutation of codon 34 (N34S). We also found four other sequence variants. Our results indicate that mutations in SPINK1 are associated with chronic pancreatitis.
Assuntos
Mutação/genética , Pancreatite/genética , Inibidor da Tripsina Pancreática de Kazal/genética , Adolescente , Criança , Cromossomos Humanos Par 5/genética , Doença Crônica , Análise Mutacional de DNA , Éxons/genética , Feminino , Genótipo , Haplótipos/genética , Humanos , Íntrons/genética , Desequilíbrio de Ligação/genética , Escore Lod , Masculino , Modelos Biológicos , Mutação de Sentido Incorreto/genética , Polimorfismo Genético/genéticaRESUMO
Hypertrophic pulmonary osteoarthropathy (often referred to as Marie-Bamberger syndrome) occurs in 1â-â5â% of all patients with non-small cell lung cancer (NSCLC) as a paraneoplastic syndrome. The complete syndrome is characterised by clubbing of the fingers and toes (often without hypoxia) and pain in the joints and tubular bones. On the basis of four clinical cases, this article shows that this syndrome can precede tumour-specific symptoms and that it is still often overlooked by physicians. An early suspicion of this syndrome is of great clinical value because it can lead to a diagnosis of NSCLC at an earlier tumour stage. In addition to the case reports, the current literature on hypertrophic pulmonary osteoarthropathy is reviewed in this article, with special reference to pathogenetic concepts und to therapeutic options.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Osteoartropatia Hipertrófica Secundária/diagnóstico , Osteoartropatia Hipertrófica Secundária/etiologia , Síndromes Paraneoplásicas/diagnóstico , Síndromes Paraneoplásicas/etiologia , Adenocarcinoma/diagnóstico , Adenocarcinoma/patologia , Adenocarcinoma/terapia , Adulto , Idoso , Broncoscopia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/terapia , Terapia Combinada , Progressão da Doença , Diagnóstico Precoce , Feminino , Humanos , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/terapia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Osteoartropatia Hipertrófica Secundária/terapia , Síndromes Paraneoplásicas/terapia , Prognóstico , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: Xenobiotic mediated cellular injury is thought to play a major role in the pathogenesis of pancreatic diseases. Genetic variations that reduce the expression or activity of detoxifying phase II biotransformation enzymes such as the UDP-glucuronosyltransferases might be important in this respect. Recently, a UGT1A7 low detoxification activity allele, UGT1A7*3, has been linked to pancreatic cancer and alcoholic chronic pancreatitis. OBJECTIVE: To investigate whether UGT1A7 polymorphisms contribute to the risk of pancreatitis and pancreatic cancer. METHODS: Genetic polymorphisms in the UGT1A7 gene were assessed in a large cohort of patients with different types of pancreatitis and pancreatic cancer originating from the Czech Republic (n = 93), Germany (n = 638), Netherlands (n = 136), and Switzerland (n = 106), and in healthy (n = 1409) and alcoholic (n = 123) controls from the same populations. Polymorphisms were determined by melting curve analysis using fluorescence resonance energy transfer probes. In addition, 229 Dutch subjects were analysed by restriction fragment length polymorphism. RESULTS: The frequencies of UGT1A7 genotypes did not differ between patients with acute or chronic pancreatitis or pancreatic adenocarcinoma and alcoholic and healthy controls. CONCLUSIONS: The data suggest that, in contrast to earlier studies, UGT1A7 polymorphisms do not predispose patients to the development of pancreatic cancer and pancreatitis.
Assuntos
Predisposição Genética para Doença , Glucuronosiltransferase/genética , Pancreatopatias/enzimologia , Polimorfismo Genético , Adenocarcinoma/metabolismo , Adulto , Estudos de Coortes , Feminino , Frequência do Gene , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite/enzimologia , XenobióticosRESUMO
The main indication for orthotopic liver transplantation (OLTx) in Wilson's disease (WD) is severe hepatic decompensation. Our 15-year-old patient is the second case to date in whom OLTx was performed because of neurologic manifestations resulting from WD. His initial condition involving recurrent headaches, tremor, and athetoid hand movements progressively deteriorated during therapy with D-penicillamine, zinc sulfate, and trientine until he was severely dysarthric, unable to walk, and bedridden. After OLTx, his neurologic condition became almost normal.
Assuntos
Encefalopatias/terapia , Degeneração Hepatolenticular/terapia , Transplante de Fígado , Adolescente , Encefalopatias/complicações , Cobre/metabolismo , Degeneração Hepatolenticular/complicações , Degeneração Hepatolenticular/metabolismo , Humanos , MasculinoRESUMO
Using sensitive radioimmunoassay techniques, the formation of cysteinyl-leukotrienes (LT) and prostaglandin (PG) F2 alpha was investigated in human brain tissue slices in vitro. Under basal conditions spontaneous release of considerable amounts of LTC4-like material and PGF2 alpha could be detected from slices of both human grey and white matter. Ionophore A23187 stimulated the release of large amounts of LTC4-like material while leaving unaffected the formation of the cyclo-oxygenase product PGF2 alpha. Incubation of grey or white matter in the presence of the cyclo-oxygenase inhibitor indomethacin inhibited the release of PGF2 alpha but did not affect that of LTC4-like material. Preincubation of brain tissue in the presence of the lipoxygenase inhibitor nordihydroguaiaretic acid (NDGA) abolished the ionophore A23187-induced release of LTC4-like material from both grey and white matter and also significantly reduced the spontaneous release of LTC4-like material from white matter slices. Formation of PGF2 alpha was not affected by NDGA. Using the isolated guinea pig ileum the LTC4-like material was shown to possess biological activity which could be antagonized with the slow-reacting substance of anaphylaxis (SRS-A) antagonist FPL 55712. By reversed phase HPLC the immunoreactive LTC4-like material from human grey matter was shown to coelute with authentic LTC4, LTD4 and LTE4, while material from human white matter coeluted with authentic LTD4 and LTE4. The capacity of human brain tissue to synthesize cysteinyl-LT may be important for cellular functions in the central nervous system.
Assuntos
Encéfalo/metabolismo , SRS-A/biossíntese , Encéfalo/efeitos dos fármacos , Calcimicina/farmacologia , Dimetil Sulfóxido/farmacologia , Dinoprosta/biossíntese , Humanos , Técnicas In Vitro , Indometacina/farmacologia , Cinética , Masoprocol/farmacologia , Valores de ReferênciaRESUMO
Using radioimmunoassay techniques we studied the formation of the 5-lipoxygenase-derived cysteinyl-leukotrienes (LT) in comparison to the cyclooxygenase product thromboxane (TX) B2 in whole human blood allowed to clot at 37 degrees C in vitro. Spontaneous clotting resulted in a time-dependent release of smaller amounts of cysteinyl-LT as well as release of large amounts of TXB2 into the serum. Cysteinyl-LT were characterized by their immunoreactive behaviour and their biological activity in the guinea pig ileum bioassay, an effect which could be antagonized by the SRS-A antagonist FPL 55712 (0.38 microM). By reversed phase HPLC cysteinyl-LT in the serum were identified as a mixture of LTC4, LTD4 and LTE4. At 90 and 120 min part of the immunoreactive material consisted of the omega-oxidized metabolite 20-OH-LTE4. Almost complete inhibition of cyclooxygenase activity by indomethacin (2.8 microM) did not affect cysteinyl-LT formation by clotting whole human blood in vitro nor did activation of platelets by compounds such as the TX mimetic U 46619 (10 microM), platelet-activating factor (PAF, 1 microM) or thrombin (3 IU/ml). In contrast, the lipoxygenase inhibitor nordihydroguaiaretic acid (NDGA, 10 microM), the Ca2+-chelating anticoagulants trisodium citrate (10 microM) and edetate disodium (EDTA, 5.4 mM) as well as the functionally unrelated heparin (20 IU/ml) significantly inhibited the formation of cysteinyl-LT as well as of TXB2. Thus, an event related to the process of clotting of whole human blood appears to be able to induce cysteinyl-LT formation in amounts which might be functionally relevant during thromboembolic events.
Assuntos
Coagulação Sanguínea , SRS-A/sangue , Adulto , Animais , Bioensaio , Cromatografia Líquida de Alta Pressão , Cromonas/farmacologia , Citratos/farmacologia , Ácido Cítrico , Ácido Edético/farmacologia , Cobaias , Heparina/farmacologia , Humanos , Íleo/efeitos dos fármacos , Íleo/fisiologia , Cinética , Leucotrieno E4 , Masculino , Masoprocol/farmacologia , Contração Muscular/efeitos dos fármacos , SRS-A/análogos & derivados , SRS-A/antagonistas & inibidores , SRS-A/farmacologia , Tromboxano B2/sangueRESUMO
Cadmium concentrations were measured by flameless atomic absorption spectrometry in blood and mature milk of 15 nonsmoking and 56 smoking mothers during the nursing period. Both blood and milk concentrations increased with increasing cigarette consumption. The median blood and milk concentrations in nonsmokers were 0.54 and 0.07 microgram/l, respectively; these values rose to 1.54 and 0.16 micrograms/l in blood and milk of mothers smoking more than 20 cigarettes per day. Milk concentrations of cadmium were approximately 10% of corresponding blood concentrations. The cadmium exposure of infants nursed by nonsmoking as well as by smoking mothers was far below the exposure of formula-fed infants or the provisional acceptable weekly intake level set by the WHO.
Assuntos
Cádmio/análise , Leite Humano/análise , Fumar , Adolescente , Adulto , Cádmio/metabolismo , Feminino , Humanos , LactenteRESUMO
AIM: of our study was to investigate the effect of pre- and postnatal passive tobacco smoke exposure on the incidence of allergic sensitization. PATIENTS AND METHODS: Specific sensitization to food, outdoor and indoor allergens was determined in 342 children at the age of 1, 2 and 3 years. Parents were asked about their smoking habit at the birth of their children, at 18 months and 3 years of age. RESULTS: Multivariate regression analysis indicated, that during the first 3 years of life, pre- and postnatally exposed children had a significantly higher risk for sensitization to food allergens compared to children never exposed to tobacco smoke (OR 2.2, 95% CI 1.1-4.2; P = 0.02). With respect to inhalant allergens no significant influence of tobacco smoke exposure on specific sensitization could be demonstrated. CONCLUSION: During early childhood both pre- and postnatal tobacco smoke exposure has an adjuvant effect on allergic sensitization to food allergens.
Assuntos
Feto/efeitos dos fármacos , Hipersensibilidade/etiologia , Troca Materno-Fetal , Poluição por Fumaça de Tabaco/efeitos adversos , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Gravidez , Análise de RegressãoRESUMO
Test-retest reliability and sex differences when viewed in a distorted room were investigated. The presence of the Honi phenomenon, which is less change in apparent size of a spouse than of a stranger, was examined. A reliability coefficient was obtained by testing 27 college men twice. Judgments of size from 25 of the men and 25 women who viewed black disc targets and also from 10 women viewing husbands' and strangers' photographs were compared. The reliability was high, .87. Sex difference was significant. Women's larger reading was interpreted as a more meaningful or valuable perception of things than men's. The Honi phenomenon does not exist.