The binding of mRNA to the ribosome is mediated by eukaryotic initiation factors eukaryotic initiation factor 4F (eIF4F), eIF4B, eIF4A, and eIF3, eIF4F binds to the mRNA cap structure and, in combination with eIF4B, is believed to unwind the secondary structure in the 5' untranslated region to facilitate ribosome binding. eIF3 associates with the 40S ribosomal subunit prior to mRNA binding. eIF4B copurifies with eIF3 and eIF4F through several purification steps, suggesting the involvement of a multisubunit complex during translation initiation. To understand the mechanism by which eIF4B promotes 40S ribosome binding to the mRNA, we studied its interactions with partner proteins by using a filter overlay (protein-protein [far Western]) assay and the two-hybrid system. In this report, we show that eIF4B self-associates and also interacts directly with the p170 subunit of eIF3. A region rich in aspartic acid, arginine, tyrosine, and glycine, termed the DRYG domain, is sufficient for self-association of eIF4B, both in vitro and in vivo, and for interaction with the p170 subunit of eIF3. These experiments suggest that eIF4B participates in mRNA-ribosome binding by acting as an intermediary between the mRNA and eIF3, via a direct interaction with the p170 subunit of eIF3.

The association between dermatomyositis and celiac disease in children has been well documented. In the adult population, however, the association has not been clearly established. A rare case of concomitant dermatomyositis and celiac disease in a 40-year-old woman is presented. After having been diagnosed with dermatomyositis and iron deficiency anemia, this patient was referred to the gastroenterology clinic to exclude a gastrointestinal malignancy. Blood tests revealed various vitamin deficiencies consistent with malabsorption. The results of gastroscopy with duodenal biopsy were consistent with celiac disease. After she was put on a strict gluten-free diet, both nutritional deficiencies and the dermatomyositis resolved. The patient's human leukocyte antigen haplotype study was positive for DR3 and DQ2, which have been shown to be associated with both juvenile dermatomyositis and celiac disease. It is suggested that patients with newly diagnosed dermatomyositis be investigated for concomitant celiac disease even in the absence of gastrointestinal symptoms.

Granulomatous hypophysitis is a rare pituitary condition that commonly presents with enlargement of the pituitary gland. A 31-year-old woman was admitted to the hospital with a severe headache and bitemporal hemianopsia. Magnetic resonance imaging (MRI) showed an 18 × 10-mm sellar mass with suprasellar extension and compression of the optic chiasm. Interestingly, brain MRI had shown no abnormal finding 4 months previously. On hormonal examination, hypopituitarism with mild hyperprolactinemia was noted. The biopsy revealed granulomatous changes with multinucleated giant cells. We herein report this rare case and discuss the relevant literature.

Although adrenocortical tumors are common, adrenocortical carcinomas are rare. Moreover, aldosterone-producing adrenocortical carcinomas without hypertension are exceedingly rare, with only two previously reported cases.

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