Type I error A type I error occurs when one rejects the null hypothesis when it is true. The probability of a type I error is the level of significance of the test of hypothesis, and is denoted by *alpha*. Usually a one-tailed test of hypothesis is is used when one talks about type I error. Examples: If the cholesterol level of healthy men is normally distributed with a mean of 180 and a standa...

Scientists have been investigating the critical role type 1 interferons (IFN-I) play in controlling viral infections for more than 50 y. Common pathogen motifs present on viral particles trigger intracellular and membrane-associated pattern recognition receptors, leading to the production of IFN-I and rapid expression of interferon stimulated genes (ISIGs). ISIGs encode proteins with direct ant...

La neurofibromatose de type 1 (NF1) ou maladie de Recklinghausen est une génodermatose autosomique dominante, elle touche de 1/3000 à 1/4000 personnes. La NF1 est caractérisée par une variabilité de son expression clinique qu'on peut retrouver au sein de la même famille. Des critères de diagnostic ont été établis en 1988. Le diagnostic de la NF1 est porté quand au moins deux des signes suivants...

Plasmacytoid dendritic cells (pDCs) are specialized producers of type I interferons (IFNs) that respond to most viruses. Because of their antiviral activity and regulatory functions in innate and adaptive immunity, type I IFNs are important not only for antiviral resistance but also in other types of infections and in immune pathology. Here we discuss recent data that begin to reveal the unique...

Type I collagen is the predominant collagen in mature tendons and ligaments, where it gives them their load-bearing mechanical properties. Fibrils of type I collagen are formed by the packing of polypeptide triple helices. Higher-order structures like fibril bundles and fibers are assembled from fibrils in the presence of other collagenous molecules and noncollagenous molecules. Curiously, howe...

History: A student nurse, aged 20, was admitted to the New Haven Hospital on October I3, I929, with a complaint of "earache". There was no history of exposure to Type I pneumococcus infection. One week before admission she developed a dry, nonproductive cough with an uncomfortable restricted feeling about the chest. There was no sore throat nor history of muscular or joint pains. On the morning...

Rhizomelic Chondrodysplasia Punctata Type I is one of the rare peroxisome disorders. We report the case of a newborn white male that developed seizures and skeletal dysmorphism. The baby had short humerus bones with stippled epiphyses, consistent with the disease. He had also delay in myelinization on brain MRI with bilateral subependymal cysts over the atria and frontal horns of the lateral ve...

A recent NIH panel in which I participated unanimously agreed that wide clinical application of immunotherapy for type I diabetes is at present inappropriate. The risks of premature application of such therapy outweigh potential benefits. In this editorial, I will briefly review the current information upon which I and my colleagues have begun small research trials of immunotherapy which 1 beli...

Familial chylomicronemia syndrome is a group of rare genetic disorders characterized by deficient activity of an enzyme lipoprotein lipase or apo-protein C-II deficiency. In this paper we present an infant with massive hyperchylomicronemia and severe pancreatitis. Exchange transfusion for controlling hypertriglyceridemia and pancreatitis led to an increase in hyperviscosity which resulted in en...