Scurvy and Tinea Corporis Simulating Leukocytoclastic Vasculitis.

Leukocytoclastic vasculitis (LCV) is a small vessel inflammatory condition considered to be caused by circulating immune complexes and often occurs after an acute infection or exposure to a new medication, although it may be associated with an underlying systemic disease or be idiopathic in nature. It is important to determine the etiology, identify the extent of the disease for early intervention and appropriate management, and treat and/or eliminate the underlying cause. Here, we report cases of scurvy and tinea corporis that presented with histopathologic features of LCV and had significant clinical improvement with treatment of the underlying etiologies.

A rare cause of melena.

Melanoma presenting in the gastrointestinal tract is commonly due to metastasis from a primary cutaneous or ocular lesion. There have been a few case reports of primary GI melanoma which is commonly seen in the rectum and anus. We report a case of a 77-year-old man who presented with GI bleeding and was found to have a primary small bowel melanoma.

Nucleoporin Seh1 Interacts with Olig2/Brd7 to Promote Oligodendrocyte Differentiation and Myelination.

Nucleoporins (Nups) are involved in neural development, and alterations in Nup genes are linked to human neurological diseases. However, physiological functions of specific Nups and the underlying mechanisms involved in these processes remain elusive. Here, we show that tissue-specific depletion of the nucleoporin Seh1 causes dramatic myelination defects in the CNS.

Sec13 Regulates Expression of Specific Immune Factors Involved in Inflammation In Vivo.

The Sec13 protein functions in various intracellular compartments including the nuclear pore complex, COPII-coated vesicles, and inside the nucleus as a transcription regulator. Here we developed a mouse model that expresses low levels of Sec13 (Sec13(H/-)) to assess its functions in vivo, as Sec13 knockout is lethal. These Sec13 mutant mice did not present gross defects in anatomy and physiology.

Vesicular stomatitis virus inhibits mitotic progression and triggers cell death.

Vesicular stomatitis virus (VSV) infects and kills a wide range of cell types; however, the mechanisms involved in VSV-mediated cell death are not fully understood. Here we show that VSV infection interferes with mitotic progression, resulting in cell death. This effect requires the interaction of VSV matrix (M) protein with the Rae1-Nup98 complex in mitosis, which is associated with a subset of ribonucleoproteins (RNPs).