Epstein-Barr virus associated hemophagocytic lymphohistiocytosis in a rheumatic patient receiving abatacept therapy.

Hemophagocytic lymphohistiocytosis (HLH) is a life- threatening hyperinflammatory disease that causes extensive organ damage. It is generally triggered by viral, fungal, or parasitic infections in the setting of hematologic disease-induced immune deficiency. Occurrences in rheumatologic disease are less frequent, with the syndrome developing most often in patients with systemic lupus erythematosus and adult-onset Still disease. It is believed that the immunosuppression induced by rheumatologic disease itself and exacerbation by immunomodulatory therapies predispose to infection and subsequently HLH. Abatacept is a relatively new disease-modifying agent for rheumatoid arthritis (RA) that has been associated with varicella zoster virus, cytomegalovirus, and Epstein-Barr virus (EBV) infections, but not previously in the setting of HLH. Here we report a unique case of EBV-associated HLH in a RA patient receiving abatacept therapy.

Application of molecular techniques in the diagnosis, prognosis and management of patients with colorectal cancer: a practical approach.

There has been an increasing role for molecular diagnostics in the diagnosis and management of cancer, and colorectal carcinoma is no exception. Recent molecular advances have elucidated 3 broad molecular subtypes of colorectal cancer, including chromosomal instability, microsatellite instability, and cytosine-phosphoguanine island methylator phenotype, which will be discussed. Also, the common syndromes associated with colorectal carcinoma will be reviewed with a focus on the differentiation between Lynch syndrome and microsatellite unstable tumors. Molecular biomarkers for predictive and prognostic markers are also becoming widely used, and due to the clinical use of monoclonal antibodies to the epidermal growth factor receptor, an emphasis is placed on that pathway.

The dual functions of receptor interacting protein 1 in fas-induced hepatocyte death during sepsis.

In examining the liver's response to sepsis, our laboratory has found that septic hepatocytes exhibit a higher degree of necrosis when compared with septic thymocytes, which typically die through the canonical apoptotic pathway. Recently, an adaptor protein associated with the Fas/TNF death receptor pathway, receptor interacting protein 1 (RIP1), has been shown to be critical for determining whether a cell's death is apoptotic or necrotic. We propose to test the central hypothesis that RIP1 activation by death receptor (Fas) during sepsis determines whether the hepatocytes' fate is apoptotic versus necrotic. We approached this problem by delivering RIP1 siRNA in vivo to C57BL/6 mice and observing changes in mortality after septic challenge. Contrary to our hypothesis, RIP1-silenced mice did not survive as long as scrambled sequence injected controls (22.2% vs. 50.0% 14 days after cecal ligation and puncture, respectively). When we used a pharmacological/synthetic antagonist of RIP1 kinase, necrostatin 1 (Nec1), and examined the mortality of Nec1-treated mice, there was no difference from the RIP1 siRNA-treated mice (20.0% vs. 22.2%, respectively). Furthermore, we carried out a series of comparative histological studies, which indicated that septic mice pretreated with Nec1 exhibited a preservation of liver glycogen stores (represented by periodic acid Schiff stain) versus siRNA-treated mice, which exhibit lower glycogen stores as well as altered morphology. Furthermore, the histological studies also revealed that Nec1 treatment in septic mice increases caspase 3 activity. We speculate that these contradictatory findings are due to the dual-signaling responsibilities of RIP1, where the RIP1 kinase domain can induce death through Fas ligation while also initiating prosurvival signaling through nuclear factor κB (NF-κB).

Pathobiology of colorectal cancer hepatic metastases with an emphasis on prognostic factors.

Colorectal cancer is the second leading cause of cancer related death in the United States. The majority of these deaths are due to metastasis, with the liver easily accounting as the most common site of deposit. While there are multiple steps in the CRC hepatic metastatic cascade, this review attempts to summarize the different processes involved, focusing on the most recent discoveries, as well as the associated effects in relation to prognosis.

A human immunodeficiency virus-positive infant with probable congenital histoplasmosis in a nonendemic area.

A 5-week-old infant presented with a fever, and was diagnosed with congenital human immunodeficiency virus and histoplasmosis. Both infections were likely transmitted vertically. The child was effectively treated with antifungal medications and highly active antiretroviral therapy. This represents the first case of delayed presentation of vertically transmitted histoplasmosis, and the first case in a nonendemic area.

Synthesis and biologically relevant properties of polyphosphazene polyacids.

Polyphosphazene polyacids show potential as immunostimulating compounds and materials for microencapsulation. Their synthesis requires multistep chemical transition from a hydrolytically unstable macromolecular precursor, poly(dichlorophosphazene), to a water-soluble polyelectrolyte. Insufficient synthetic control in these reactions can lead to molecular weight variations and formation of macromolecules with "structural defects" resulting in significant variations in polymer performance. Simple and reproducible "one pot-one solvent" method is reported for the preparation of polyphosphazene polyacids-poly[di(carboxylatophenoxy)phosphazene] and its copolymers. Molecular weight characteristics and polymer compositions were studied as a function of reaction parameters. Macromolecular byproducts, incompletely substituted polymers containing hydroxyl groups and partially deprotected polymers containing propyl ester functionalities, were synthesized and characterized. It was demonstrated, that the presence of such groups can affect polymer characteristics, such as hydrolytic degradation profiles, immunostimulating activity, and microsphere forming properties. In vivo studies showed that the immunostimulating activity of polyphosphazene polyacids correlates with the content of acid functionalities in the polymer.