Purtscher-Like Retinopathy Associated With Acute Pancreatitis: A Case Report.

Purtscher retinopathy is a type of ischemic retinopathy that can lead to a devastating visual prognosis. With no significantly proven treatment, preventing the condition by managing the causes and risk factors is the best way to preserve vision. This case report will focus on a patient with Purtscher-like retinopathy associated with acute pancreatitis, including exam findings, risk factors, and a discussion of treatment options.

Developmental expression of insulin receptor substrate-2 during dimethylsulfoxide-induced differentiation of human HL-60 cells.

Insulin receptor substrate-2 (IRS-2) is phosphorylated on tyrosine by a number of cytokine receptors and is implicated in the activation of phosphatidylinositol 3'-kinase (PI3-kinase). Here, we demonstrate that induction of granulocytic differentiation of human promyeloid HL-60 cells leads to an increase in the amount of IRS-2 that is phosphorylated in response to insulin-like growth factor (IGF)-I. Although PI3-kinase is often activated following interaction with IRS-1, we could not detect IRS-1 protein, IRS-1 mRNA, or IRS-1-precipitable PI3-kinase enzymatic activity.

Elevated cyclin E levels, inactive retinoblastoma protein, and suppression of the p27(KIP1) inhibitor characterize early development of promyeloid cells into macrophages.

Cyclin-dependent kinase inhibitors such as p27(KIP1) have recently been shown to lead to cellular differentiation by causing cell cycle arrest, but it is unknown whether similar events occur in differentiating promyeloid cells. Hematopoietic progenitor cells undergo lineage-restricted differentiation, which is accompanied by expression of distinct maturation markers. Here we show that the classical growth factor insulin-like growth factor I (IGF-I) potently promotes vitamin D(3)-induced macrophage differentiation of promyeloid cells, as assessed by measurement of a coordinate increase in expression of the integrin alpha subunit CD11b, the CD14 lipopolysaccharide receptor, and the macrophage-specific esterase, alpha-naphthyl acetate esterase, as early as 24 h following initiation of terminal differentiation.

A new mechanism of neurodegeneration: a proinflammatory cytokine inhibits receptor signaling by a survival peptide.

Heightened expression of both a proinflammatory cytokine, tumor necrosis factor alpha (TNF-alpha), and a survival peptide, insulin-like growth factor I (IGF-I), occurs in diverse diseases of the central nervous system, including Alzheimer's disease, multiple sclerosis, the AIDS-dementia complex, and cerebral ischemia. Conventional roles for these two proteins are neuroprotection by IGF-I and neurotoxicity by TNF-alpha. Although the mechanisms of action for IGF-I and TNF-alpha in the central nervous system originally were established as disparate and unrelated, we hypothesized that the signaling pathways of these two cytokines may interact during neurodegeneration.

Expression and localization of p80 and p68 interleukin-1 receptor proteins in the brain of adult mice.

The biological effects of interleukin-1 (IL-1) are mediated by two distinct receptors, the p80 type I IL-1 and p68 type II IL-1 receptor proteins (IL-1RI and IL-1RII, respectively), both of which have been recently co-localized to the growth hormone synthesizing cells of the adenohypophysis. Previous studies have shown that IL-1 can bind to specific structures in the central nervous system, but the distribution of IL-1RI and IL-1RII proteins in the adult mouse brain has not been reported. Here we have used immunohistochemistry to study the expression, distribution and cellular localization of both isoforms of the IL-1 receptor proteins in the adult mouse brain.