Response to direct‐acting antivirals for hepatitis C treatment in vertically HIV/HCV co‐infected patients

Direct‐acting antivirals (DAAs) for HCV treatment have improved tolerance and efficacy among adults, but experience in vertical transmission is scarce. In our vertically HIV/HCV co‐infected youth cohort of 58 patients, DAA achieved excellent rates of cure among naïve and pretreated individuals. Treating vertically infected seems important as 29.6% displayed advanced fibrosis at treatment initiation.     

Mechanical elasticity as a physical signature of conformational dynamics in a virus particle

In this study we test the hypothesis that mechanically elastic regions in a virus particle (or large biomolecular complex) must coincide with conformationally dynamic regions, because both properties are intrinsically correlated. Hypothesis-derived predictions were subjected to verification by using 19 variants of the minute virus of mice capsid. The structural modifications in these variants reduced, preserved, or restored the conformational dynamism of regions surrounding capsid pores that are involved in molecular translocation events required for virus infectivity. The mechanical elasticity of the modified capsids was analyzed by atomic force microscopy, and the results corroborated every prediction tested: Any mutation (or chemical cross-linking) that impaired a conformational rearrangement of the pore regions increased their mechanical stiffness. On the contrary, any mutation that preserved the dynamics of the pore regions also preserved their elasticity. Moreover, any pseudo-reversion that restored the dynamics of the pore regions (lost through previous mutation) also restored their elasticity. Finally, no correlation was observed between dynamics of the pore regions and mechanical elasticity of other capsid regions. This study (i) corroborates the hypothesis that local mechanical elasticity and conformational dynamics in a viral particle are intrinsically correlated; (ii) proposes that determination by atomic force microscopy of local mechanical elasticity, combined with mutational analysis, may be used to identify and study conformationally dynamic regions in virus particles and large biomolecular complexes; (iii) supports a connection between mechanical properties and biological function in a virus; (iv) shows that viral capsids can be greatly stiffened by protein engineering for nanotechnological applications.     

Bruton tyrosine kinase inhibition is a novel therapeutic strategy targeting tumor in the bone marrow microenvironment in multiple myeloma

Bruton tyrosine kinase (Btk) has a well-defined role in B-cell development, whereas its expression in osteoclasts (OCs) further suggests a role in osteoclastogenesis. Here we investigated effects of PCI-32765, an oral and selective Btk inhibitor, on osteoclastogenesis as well as on multiple myeloma (MM) growth within the BM microenvironment. PCI-32765 blocked RANKL/M-CSF-induced phosphorylation of Btk and downstream PLC-γ2 in OCs, resulting in diminished TRAP5b (ED(50) = 17nM) and bone resorption activity. PCI-32765 also inhibited secretion of multiple cytokines and chemokines from OC and BM stromal cell cultures from both normal donors (ED(50) = 0.5nM) and MM patients. It decreased SDF-1-induced migration of MM cells, and down-regulated MIP1-α/CCL3 in MM cells. It also blocked MM cell growth and survival triggered by IL-6 or coculture with BM stromal cells or OCs in vitro. Importantly, PCI-32765 treatment significantly inhibits in vivo MM cell growth (P < .03) and MM cell-induced osteolysis of implanted human bone chips in SCID mice. Moreover, PCI-32765 prevents in vitro colony formation by stem-like cells from MM patients. Together, these results delineate functional sequelae of Btk activation mediating osteolysis and growth of MM cells, supporting evaluation of PCI-32765 as a novel therapeutic in MM.     

Opciones de tratamiento quirúrgico en la estenosis de uretra bulbar

ObjectiveTo review the outcome of bulbar urethroplasty using two stage surgical techniques.Material and methodsTwenty-two of the 35 patients studied corresponded to end-to-end urethroplasty (ATT) and 13 to dorsal onlay graft (DOG) in preputial skin or oral mucosa variants. Clinical outcome was considered a failure when postoperative surgery was needed or the uroflowmetry was less than 15 ml/s. The following variables were studied: age, previous surgery, number of urethrotomies and stricture length. The curves and log-rank Curves using the log-rank were elaborated for follow-up and comparison, with the Cox regression model for risk factors.ResultsMean follow-up was 40.02 months. Of all the cases. 85.71% were successful. Of these, 86.36% were in the ATT group and 84.61% in the DOG group. There were no significant differences in the comparative LR test based in stricture length, previous surgery between both group and individualized for each management. The Cox regression model showed a risk of failure in the technique for the elderly patients (OR 2.2), it not achieving statistical significance in the remaining variables.ConclusionsThe success rate achieved with the ATT technique is verified a gold standard option in short strictures. The DOG is shown as a valid option in long strictures in bulbar urethral in medium follow-up, using a oral mucosa or preputial onlay graft. More long-term follow-up must be performed with a greater number of patients to better evaluate these results.