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Haematemesis is a worrying sign, generally related to acute upper gastrointestinal bleeding and potentially life-threatening condition. We present a case of a 15-year-old Caucasian girl who was belatedly diagnosed with oral bleeding because it was not related to the most common aetiologic factors. In fact, she was undergoing orthodontic treatment with a Nance palatal arch, an appliance used to reinforce anchorage during teeth movements. In her case haematemesis was a sign of inflammation and necrosis occurring in the palatal mucosa, under the acrylic button of palatal arch. The appliance was removed; antibiotic and Chlorhexidine 0.12% were recommended. After a 6-week follow-up, no pathological signs were present and the orthodontic treatment was resumed. Both physicians and dentists should be aware of the possible side effect of the Nance palatal arch use; this could help in achieving a diagnosis and providing a correct treatment. Orthodontists should avoid excessive compression over the palatal mucosa and check the appliance condition during every follow-up in order to avoid necrosis of the palatal mucosa.  相似文献   
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Apoptosis normally occurs in the human placenta. As a consequence, cell blebs, post-apoptotic debris (also referred to as syncytial knots) and membrane microparticles are released into the blood of pregnant women. These events become prominent during the best-characterized pregnancy complication, pre-eclampsia. An excessive or deregulated cell death, which results in the generation of an overwhelming burden of apoptotic material, alarms the immune system. This plays a role in the pathogenesis of systemic connective tissue diseases and possibly of small vessels vasculitis. Infiltration of leukocytes and activation of endothelial cells and platelets are hallmarks of normal pregnancy, indicating that physiologic pregnancy is a condition characterized by an activation of the innate immune system. Conversely, a failure in the physiologic termination of inflammatory events is probably a requirement for pre-eclampsia to develop. Here, we discuss recent findings suggesting a link between deregulated disposal of placental debris, the generation of endogenous pro-inflammatory signals (alarmins) and the widespread vascular inflammation that characterizes on one hand pre-eclampsia and on the other systemic autoimmune diseases.  相似文献   
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Iron overload (IO) is poorly investigated in the congenital haemolytic anaemias (CHAs), a heterogeneous group of rare inherited diseases encompassing abnormalities of the erythrocyte membrane and metabolism, and defects of the erythropoiesis. In this study we systematically evaluated routine iron parameters and cardiac and hepatic magnetic resonance imaging, together with erythropoietin, hepcidin, non-transferrin bound iron (NTBI), and cytokine serum levels in patients with different CHAs. We found that 40% of patients had a liver iron concentration (LIC) >4 mg Fe/g dry weight. Hepatic IO was associated with ferritin levels (P = 0·0025), transferrin saturation (TfSat, P = 0·002) and NTBI (P = 0·003). Moreover, ferritin >500 μg/l plus TfSat >60% was demonstrated as the best combination able to identify increased LIC, and TfSat alteration as more important in cases with discordant values. Possible confounding factors, such as transfusions, hepatic disease, metabolic syndrome and hereditary haemochromatosis-associated mutations, had negligible effects on IO. Erythropoietin and hepcidin levels were increased in CHAs compared with controls, correlating with LIC and ferritin, respectively. Regarding cytokines, γ-interferon (IFN-γ) was increased, and both interleukin 6 and IFN-γ levels positively correlated with ferritin and hepcidin levels. Overall, these findings suggest the existence of a vicious cycle between chronic haemolysis, inflammatory response and IO in CHAs.  相似文献   
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Objective: Metabolic disorders are a pandemic and increasing health problem. Women of childbearing age may also be affected, thus an abnormal metabolism may interfere with pregnancy short- and long-term outcomes, harming both mother and child. In the context of an abnormal maternal and intrauterine metabolic milieu the development of fetal organs, including pancreas, may be affected.

Aim: To investigate the effects of pregnancy metabolic disorders on the morphology of pancreatic Langerhans islets in human late-third trimester stillborn fetuses.

Methods: Samples from fetal pancreas underwent a quantitative histological evaluation to detect differences between pregnancy with (cases, n?=?9) or without (controls, n?=?6) abnormal metabolism.

Results: Results show that the islets size increases in fetuses from dysmetabolic pregnancies and that this increment is related to both beta-cell hyperplasia and hypertrophy. Moreover, according to pregnancy and fetal metabolic disorders, a threshold of abnormal size of the islets has been identified. Above this threshold the size of fetal pancreatic Langerhans islets should be considered excessively increased.

Conclusion: The study suggests that an accurate fetal pancreas analysis supplies an important tool in stillborn fetus, to discover metabolic disturbances that should be kept in mind and managed in future pregnancies.  相似文献   
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