To identify host proteins interacting with Tomato bushy stunt virus (TBSV) replication proteins in a genomewide scale, we have used a yeast (Saccharomyces cerevisiae) proteome microarray carrying 4,088 purified proteins. This approach led to the identification of 58 yeast proteins that interacted with p33 replication protein. The identified host proteins included protein chaperones, ubiquitin-associated proteins, translation factors, RNA-modifying enzymes, and other proteins with yet-unknown functions. We confirmed that 19 of the identified host proteins bound to p33 in vitro or in a split-ubiquitin-based two-hybrid assay. Further analysis of Cdc34p E2 ubiquitin-conjugating enzyme, which is one of the host proteins interacting with p33, revealed that Cdc34p is a novel component of the purified viral replicase. Downregulation of Cdc34p expression in yeast, which supports replication of a TBSV replicon RNA (repRNA), reduced repRNA accumulation and the activity of the tombusvirus replicase by up to fivefold. Overexpression of wild-type Cdc34p, but not that of an E2-defective mutant of Cdc34p, increased repRNA accumulation, suggesting a significant role for the ubiquitin-conjugating enzyme function of Cdc34p in TBSV replication. Also, Cdc34p was able to ubiquitinate p33 in vitro. In addition, we have shown that p33 becomes ubiquitinated in vivo. We propose that ubiquitination of p33 likely alters its function or affects the recruitment of host factors during TBSV replication.

The hope and expectation is that interferon is eliminated from the armamentarium of HCV therapy and that all-oral therapies prove effective although interferon in combination with multiple drugs may still be required to treat select patients. In addition, there is a need to develop effective therapies for all HCV genotypes with simple and well-tolerated regimes.

(HCC) is the third most common cause of cancer-related deaths worldwide, and each year, approximately 750,000 new cases are diagnosed.1 Surveillance strategies for patients with cirrhosis, who have an HCC incidence of 1.5% to 6%/year, can lead to a 3 to 9 month increase in mean life expectancy. 2 As the incidence of liver cancer continues to rise, effective surveillance programs are necessary in order to maximize patient outcomes. Symptomatic advanced-stage HCC has dismal outcomes (5-year life expectancy < 10%). In comparison, liver cancer identified before the onset of symptoms is more amenable to treatment, with 5-year survival rates greater than 50% for both resection and liver transplantation. 2 For surveillance programs to be effective in maximizing life expectancy outcomes, identifying risk factors for HCC is essential.The single largest risk factor in the development of HCC is cirrhosis of any etiology, which is present in 70% to 90% of those who have primary liver cancer 3 (Table 1). Following this, hepatitis B virus (HBV) infection is a significant predisposing factor for the development of HCC and accounts for more than 50% of all cases 4 ( Other notable causes of cirrhosis can increase the risk for the development of HCC (Table 2). Patients with genetic hemochromatosis are susceptible to developing cirrhosis. For those in whom cirrhosis is established, the relative risk for liver cancer is approximately 20-fold higher. The incidence of liver cancer in individuals with stage 4 primary biliary cirrhosis is similar to the incidence in patients with HCV and cirrhosis, and this suggests that primary biliary cirrhosis confers a high risk for HCC.

While daclatasvir has pangenotypic activity, it has a lower barrier to resistance in Genotype 1a but has been found to be very effective in Genotype 1b patients. However, Genotype 1a patients can be successfully treated with the addition of one or more DAAs alone or in combination with peginterferon and ribavirin. The future for daclatasvir and other DAAs is very encouraging in that all-oral therapies are likely to be effective and well-tolerated.

Early revascularization is critical to reduce morbidity after myocardial infarction, although reperfusion incites additional oxidative injury. Superoxide dismutase (SOD) is an antioxidant that scavenges reactive oxygen species (ROS) but has low endogenous expression and rapid myocardial washout when administered exogenously. This study utilizes a novel nanoparticle carrier to improve exogeneous SOD retention while preserving enzyme function. Its role is assessed in preserving cardiac function after myocardial ischemia‐reperfusion (I/R) injury. Here, nanoparticle‐encapsulated SOD (NP‐SOD) exhibits similar enzyme activity as free SOD, measured by ferricytochrome‐c assay. In an in vitro I/R model, free and NP‐SOD reduce active ROS, preserve mitochondrial integrity, and improve cell viability compared to controls. In a rat in vivo I/R injury model, NP‐encapsulation of fluorescent‐tagged SOD improves intramyocardial retention after direct injection. Intramyocardial NP‐SOD administration in vivo improves left ventricular contractility at 3‐h post‐reperfusion by echocardiography and 4‐weeks by echocardiography and invasive pressure–volume catheter analysis. These findings suggest that NP‐SOD mitigates ROS damage in cardiac I/R injury in vitro and maximizes retention in vivo. NP‐SOD further attenuates acute injury and protects against myocyte loss and chronic adverse ventricular remodeling, demonstrating potential for translating NP‐SOD as a therapy to mitigate myocardial I/R injury.