LuSIV Cells: A Reporter Cell Line for the Detection and Quantitation of a Single Cycle of HIV and SIV Replication

AbstractA single cycle of viral replication is the time required for a virus to enter the host cell, replicate its genome, and produce infectious progeny virions. The primate lentiviruses, human immunodeficiency virus (HIV) and simian immunodeficiency virus (SIV), require on average 24 h to complete one cycle of replication. We have now developed and characterized a reporter assay system in CEMx174 cells for the quantitative measurement of HIV/SIV infection within a single replication cycle. The SIVmac239 LTR (−225 → +149) was cloned upstream of the firefly luciferase reporter gene and this reporter plasmid is maintained in CEMx174 cells under stable selection. This cell line, designated LuSIV, is highly sensitive to infection by primary and laboratory strains of HIV/SIV, resulting in Tat-mediated expression of luciferase, which correlates with viral infectivity. Furthermore, manipulation of LuSIV cells for the detection of luciferase activity is easy to perform and requires a minimal amount of time as compared to current HIV/SIV detection systems. The LuSIV system is a powerful tool for the analysis of HIV/SIV infection that provides a unique assay system that can detect virus replication prior to 24 h and does not require virus to spread from cell to cell. Thus these cells can be used for the study of replication-deficient viruses and the high throughput screening of antivirals, or other inhibitors of infection

Factors Associated With Whether Pediatricians Inquire About Parents' Adverse Childhood Experiences

ObjectiveCumulative adverse childhood experiences (ACE) can have profound and lasting effects on parenting. Parents with a history of multiple ACE have greater challenges modulating their own stress responses and helping their children adapt to life stressors. We examined pediatric practice in inquiring about parents' childhood adversities as of 2013.MethodsUsing data from the 85th Periodic Survey of the American Academy of Pediatrics (AAP), we restricted analyses to the 302 pediatricians exclusively practicing general pediatrics who answered questions regarding their beliefs about childhood stressors, their role in advising parents, and whether they asked about parents' ACEs. Weighted descriptive and logistic regression analyses were conducted.ResultsDespite endorsing the influence of positive parenting on a child's life-course trajectory (96%), that their advice can impact parenting skills (79%), and that screening for social-emotional risks is within their scope of practice (81%), most pediatricians (61%) did not inquire about parents' ACE. Pediatricians who believed that their advice influences positive parenting skills inquired about more parents' ACE.ConclusionsAs of 2013, few pediatricians inquired about parents' ACEs despite recognizing their negative impact on parenting behaviors and child development. Research is needed regarding the best approaches to the prevention and amelioration of ACEs and the promotion of family and child resilience. Pediatricians need resources and education about the AAP's proposed dyadic approach to assessing family and child risk factors and strengths and to providing guidance and management

Late‐stage calcites in the Permian Capitan Formation and its equivalents, Delaware Basin margin, west Texas and New Mexico: evidence for replacement of precursor evaporites

Comparison of Upper Guadalupian fore‐reef, reef and back‐reef strata from outcrops in the Guadalupe Mountains with equivalent subsurface cores from the northern and eastern margins of the Delaware Basin indicates that extensive evaporite diagenesis has occurred in both areas. In both surface and subsurface sections, the original sediments were extensively dolomitized and most primary and secondary porosity was filled with anhydrite. These evaporites were emplaced by reflux of evaporitic fluids from shelf settings through solution‐enlarged fractures and karstic sink holes into the underlying strata. Outcrop areas today, however, contain no preserved evaporites in reef and fore‐reef sections and only partial remnants of evaporites are retained in back‐reef settings. In their place, these rocks contain minor silica, very large volumes of coarse sparry calcite and some secondary porosity. The replacement minerals locally form pseudomorphs of their evaporite precursors and, less commonly, contain solid anhydrite inclusions. Some silicification, dissolution of anhydrite and conversion of anhydrite to gypsum have occurred in these strata where they are still buried at depths in excess of 1 km; however, no calcite replacements were noted from any subsurface core samples. Subsurface alteration has also led to the widespread, late‐stage development of large‐ and small‐scale dissolution breccias. The restriction of calcite cements to very near‐surface sections, petrographic evidence that the calcites post‐date hydrocarbon emplacement, and the highly variable but generally ‘light’carbon and oxygen isotopic signatures of the spars all indicate that calcite precipitation is a very late diagenetic (telogenetic) phenomenon. Evaporite dissolution and calcitization reactions have only taken place where Permian strata were flushed with meteoric fluids as a consequence of Tertiary uplift, tilting and breaching of regional hydrological seals. A typical sequence of alteration involves initial corrosion of anhydrite, one or more stage