Targeted Enzymatic VLP-Nanoreactors with ß-Glucocerebrosidase Activity as Potential Enzyme Replacement Therapy for Gaucher's Disease.

Gaucher disease is a genetic disorder and the most common lysosomal disease caused by the deficiency of enzyme ß-glucocerebrosidase (GCase). Although enzyme replacement therapy (ERT) is successfully applied using mannose-exposed conjugated glucocerebrosidase, the lower stability of the enzyme in blood demands periodic intravenous administration that adds to the high cost of treatment. In this work, the enzyme ß-glucocerebrosidase was encapsulated inside virus-like nanoparticles (VLPs) from brome mosaic virus (BMV), and their surface was functionalized with mannose groups for targeting to macrophages. The VLP nanoreactors showed significant GCase catalytic activity. Moreover, the Michaelis-Menten constants for the free GCase enzyme (KM =0.29 mM) and the functionalized nanoreactors (KM =0.32 mM) were similar even after chemical modification. Importantly, the stability of enzymes under physiological conditions (pH 7.4, 37 °C) was enhanced by ≈11-fold after encapsulation; this is beneficial for obtaining a higher blood circulation half-life, which may decrease the cost of therapy by reducing the requirement of multiple intravenous injections. Finally, the mannose receptor targeted enzymatic nanoreactors showed enhanced internalization into macrophage cells. Thus, the catalytic activity and cell targeting suggest the potential of these nanoreactors in ERT of Gaucher's disease.

Nitrate assimilation pathway (NAP): role of structural (nit) and transporter (ntr1) genes in Fusarium oxysporum f.sp. lycopersici growth and pathogenicity.

The tomato pathogen Fusarium oxysporum f.sp. lycopersici possesses the capability to use nitrate as the only nitrogen source under aerobic and anaerobic conditions and to activate virulence-related functions when cultivated in the presence of nitrate, but not in ammonium. The genome of F. oxysporum f.sp. lycopersici encodes three paralogs nitrate reductase (NR) genes (nit1, nit2 and nit3) and one predicted ortholog of the Aspergillus nidulans high-affinity nitrate/nitrite transporters NtrA and NtrB, named ntr1. We set out to clarify the role of nit1, nit2, nit3 and ntr1 genes in nitrate assimilation and in the virulence of F. oxysporum f.sp. lycopersici. Quantitative RT-PCR analysis revealed that only nit1, nit2 and ntr1 are expressed at significant levels during growth in nitrate as the only nitrogen source. Targeted deletion of nit1 and ntr1, but not of nit2 or nit3, severely impaired growth of F. oxysporum on nitrate as nitrogen source, indicating that Nit1 and Ntr1 proteins are involved in nitrate assimilation by the fungus; biochemical analysis of nit mutants indicated that Nit1 and Nit2 enzymes contribute to about 50 and 30% of the total NR activity, respectively. In addition, a spontaneous chlorate-resistant mutant derived from F. oxysporum 4287, denoted NitFG, was characterized, showing inability to grow in nitrate under aerobic and anaerobic conditions and low levels of NR activity, in spite of its increased transcription levels of nit1 and nit2 genes. Tomato plant infection assays showed that NitFG and ∆ntr1 mutants induced an earlier death in tomato plants, whereas the single mutants ∆nit1, ∆nit2 and ∆nit1∆nit2 double mutant showed a mortality rate similar to the wild-type strain. Taken together, these results indicate that the Nit1 and Ntr1 proteins are important for nitrate assimilation of F. oxysporum f.sp. lycopersici incubated under aerobic and anaerobic conditions and that this metabolic process is not essential for the virulence of the fungus. These observations open new questions about the role of Nit1, Nit2, and Nit3 proteins in other routes of nitrate metabolism in this pathogenic fungus and in the possible regulatory role that can be exerted by the AreA protein in these routes.

Computational drug treatment simulations on projections of dysregulated protein networks derived from the myelodysplastic mutanome match clinical response in patients.

Although the majority of MDS patients fail to achieve clinical improvement to approved therapies, some patients benefit from treatment. Predicting patient response prior to therapy would improve treatment effectiveness, avoid treatment-related adverse events and reduce healthcare costs. Three separate cohorts of MDS patients were used to simulate drug response to lenalidomide alone, hypomethylating agent (HMA) alone, or HMA plus lenalidomide. Utilizing a computational biology program, genomic abnormalities in each patient were used to create an intracellular pathway map that was then used to screen for drug response. In the lenalidomide treated cohort, computer modeling correctly matched clinical responses in 37/46 patients (80%). In the second cohort, 15 HMA patients were modeled and correctly matched to responses in 12 (80%). In the third cohort, computer modeling correctly matched responses in 10/10 patients (100%). This computational biology network approach identified GGH overexpression as a potential resistance factor to HMA treatment and paradoxical activation of beta-catenin (through Csnk1a1 inhibition) as a resistance factor to lenalidomide treatment. We demonstrate that a computational technology is able to map the complexity of the MDS mutanome to simulate and predict drug response. This tool can improve understanding of MDS biology and mechanisms of drug sensitivity and resistance.

Intimate partner violence: advanced practice nurses clinical stories of success and challenge.

PURPOSE: This qualitative study presents knowledge from clinical experiences of advanced practice nurses (APNs) working with women who have experienced intimate partner violence (IPV). DATA SOURCES: Face-to-face interviews were conducted with ten APNs to discover their ways of being with, supporting, and helping women who have experienced IPV. Interviews were transcribed and analyzed using interpretive phenomenology. Analysis proceeded from whole to parts and back to whole with ongoing attention to maintaining the situational context to guide interpretation of meanings. CONCLUSIONS: APNs experience both challenges and successes in caring for women who live with IPV. Findings consist of interpretations of clinical stories to uncover knowledge embedded in practice. Healing practices and ways of being survival facilitators for women and children are identified and described. IMPLICATIONS FOR PRACTICE: APNs are in a unique position to help families who live with abuse, but may lack resources and knowledge about the most effective interventions. They may become cynical and frustrated with feelings of futility when faced with the repeating patterns associated with the cycle of violence. The goals of this study are to promote more comprehensive understanding of IPV and stimulate changes in education, practice, research, and health policy.