This is a prospective study analyzing 52 asymptomatic, consecutive patients with ankylosing spondylitis (AS), who submitted to a pulmonary investigation that included plain chest radiography, pulmonary function test (PFT), and thoracic high-resolution computed tomography (HRCT). The results were compared according to sex, race, dorsal spine involvement, thoracic diameter, smoking status, and HLA-B27. There were four patients (8%) with an altered plain chest radiograph. PFT presented a restrictive pattern in 52% of the patients. Thoracic HRCT showed abnormalities in 21 patients (40%), predominantly nonspecific linear parenchymal opacities (19%), lymphadenopathy (12%), emphysema (10%), bronchiectasis (8%), and pleural involvement (8%). Linear parenchymal opacities were associated with a smoking history (p=0.026) and dorsal spine involvement (p=0.032). HLA-B27 was not associated with any abnormality. A lower thoracic diameter was observed in patients with dorsal spine involvement (p=0.0001), restrictive pattern at PFT (p=0.023), and linear parenchymal opacities (p=0.015). The study concluded that nonspecific subclinical pulmonary involvement is frequent in AS.
Insulin resistance during pregnancy has been reported both in women and in experimental animals [1][2][3][4][5][6][7], but the mechanism of this resistance remains unclear. In vivo studies have shown that pregnant rats become progressively resistant to insulin after day 16 of gestation [5]. In these animals, the insulin resistance of skeletal muscle has been clearly demonstrated in vitro, while the insulin resistance in vivo in peripheral tissues and liver has been substantiated in studies using the euglycaemic-hyperinsulinaemic clamp technique [6,7].Insulin initiates its metabolic and growth-promoting effects by binding to the a subunit of its tetrameric receptor, thereby activating the kinase in the b subunit [8]. This interaction catalyses the intramolecular autophosphorylation of specific tyrosine residues of the b subunit which further enhances the tyrosine kinase activity of the receptor toward other protein substrates [8]. In most cells, this primary event leads to the subsequent tyrosyl phosphorylation of a cytoplasmic protein with an apparent molecular weight of 160-185 kDa, called insulin receptor substrate 1 (IRS-1) [9][10][11]. Considerable evidence indicates that insulin receptor tyrosine Diabetologia (1997) 40: 179-186 Defects in insulin signal transduction in liver and muscle of pregnant rats Summary Pregnancy is known to induce insulin resistance, but the exact molecular mechanism involved is unknown. In the present study, we have examined the levels and phosphorylation state of the insulin receptor and of insulin receptor substrate 1(IRS-1), as well as the association between IRS-1 and phosphatidylinositol 3-kinase (PI 3-kinase) in the liver and muscle of pregnant rats (day 20 of gestation) by immunoprecipitation and immunoblotting with anti-insulin receptor, anti-IRS-1, anti-PI 3-kinase and antiphosphotyrosine antibodies. There were no changes in the insulin receptor concentration in the liver and muscle of pregnant rats. However, insulin stimulation of receptor autophosphorylation, as determined by immunoblotting with antiphosphotyrosine antibody, was reduced by 30 ± 6 % (p < 0.02) in muscle and 36 ± 5 % (p < 0.01) in liver at day 20 of gestation. IRS-1 protein levels decreased by 45 ± 6 % (p < 0.002) in liver and by 56 ± 9 % (p < 0.002) in muscle of pregnant rats. In samples previously immunoprecipitated with anti-IRS-1 antibody and blotted with antiphosphotyrosine antibody, the insulin-stimulated IRS-1 phosphorylation levels in the muscle and liver of pregnant rats decreased by 70 ± 9 % (p < 0.01) and 75 ± 8 % (p < 0.01), respectively. The insulin-stimulated IRS-1 association with PI 3-kinase decreased by 81 ± 6 % in muscle (p < 0.01) and 79 ± 11 % (p < 0.01) in the liver during pregnancy. These data suggest that changes in the early steps of insulin signal transduction may have a role in the insulin resistance observed in pregnancy. [Diabetologia (1997) 40: 179-186]
We have examined the insulin-stimulated IRS-2 association with PI 3-kinase and the phosphorylation of AKT/PKB, which is functionally located downstream of the PI 3-kinase, in aged (obese) rats. The IRS-2 protein levels were similar in 2 and 20 month-old rats in both tissues, liver and muscle. There were reductions in insulin-induced IRS-2 tyrosine phosphorylation in liver and muscle, accompanied by a decrease in IRS-2/PI 3-kinase association and in AKT/PKB phosphorylation only in muscle tissue of aged rats. This regulation may be important in the altered glucose metabolism observed in aged (obese) rats.
O granuloma reparador de células gigantes é lesão óssea rara, correspondendo a cerca de 7% de todos os tumores ósseos benignos da mandíbula, com maior incidência no sexo feminino. Embora seja considerada resposta a um trauma, este antecedente nem sempre está presente. O aspecto radiológico característico é de lesão lítica, uni ou multiloculada, com afilamento da cortical, podendo apresentar calcificações no seu interior. Neste trabalho relatamos os aspectos clínicos e radiológicos de cinco casos de granuloma reparador de células gigantes envolvendo a mandíbula e o maxilar, e as principais características que permitem o diagnóstico diferencial com outras lesões fibro-ósseas que acometem a face. Unitermos: Granuloma reparador de células gigantes. Tomografia computadorizada. Mandíbula. Maxilar. Neoplasia.Giant cell reparative granuloma -report of five cases. Giant cell reparative granuloma is an uncommon bone lesion accounting for slightly less than 7% of all benign tumors of the jaw and affecting predominantly females. It probably represents a reparative reaction to a traumatic injury, although history of trauma is not always confirmed. The characteristic radiological feature is a uni-or multilocular lytic bone defect eroding the bone cortical and occasionally presenting with calcifications within the lesion. We report the most important clinical and radiological features observed in five patients with giant cell reparative granuloma involving the mandible and the maxillae and discuss the main aspects for the differential diagnosis with other fibro-osseous lesions that affect the facial bones.Aceito para publicação em 16/12/2000.
Este trabalho tem como objetivo revisar as patologias que acometem o compartimento iliopsoas. Foi realizada análise retrospectiva de casos com acometimento do compartimento iliopsoas avaliados por tomografia computadorizada (TC), no Departamento de Radiologia da Faculdade de Ciências Médicas da Universidade Estadual de Campinas, nos últimos dez anos, confirmados por biópsia cirúrgica ou percutânea. Os principais diagnósticos encontrados foram neoplasias, abscessos e hematomas. Os achados tomográficos baseiam-se na extensão do acometimento iliopsoas, no grau de atenuação, margens da lesão, presença de gás e/ou calcificações, destruição óssea, infiltração da gordura e acometimento de estruturas abdominais adjacentes. A TC é o método de escolha na avaliação do compartimento iliopsoas, podendo ser utilizada para orientar biópsias percutâneas, cirúrgicas ou drenagem. Porém, os achados isolados do estudo por TC, sem o conhecimento da história clínica, não são específicos para permitir a diferenciação das diversas patologias que acometem o compartimento iliopsoas.
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