APOBEC3A is a specific inhibitor of the early phases of HIV-1 infection in myeloid cells

Myeloid cells play numerous roles in HIV-1 pathogenesis serving as a vehicle for viral spread and as a viral reservoir. Yet, cells of this lineage generally resist HIV-1 infection when compared to cells of other lineages, a phenomenon particularly acute during the early phases of infection. Here, we explore the role of APOBEC3A on these steps. APOBEC3A is a member of the APOBEC3 family that is highly expressed in myeloid cells, but so far lacks a known antiviral effect against retroviruses. Using ectopic expression of APOBEC3A in established cell lines and specific silencing in primary macrophages and dendritic cells, we demonstrate that the pool of APOBEC3A in target cells inhibits the early phases of HIV-1 infection and the spread of replication-competent R5-tropic HIV-1, specifically in cells of myeloid origins. In these cells, APOBEC3A affects the amount of vDNA synthesized over the course of infection. The susceptibility to the antiviral effect of APOBEC3A is conserved among primate lentiviruses, although the viral protein Vpx coded by members of the SIV(SM)/HIV-2 lineage provides partial protection from APOBEC3A during infection. Our results indicate that APOBEC3A is a previously unrecognized antiviral factor that targets primate lentiviruses specifically in myeloid cells and that acts during the early phases of infection directly in target cells. The findings presented here open up new venues on the role of APOBEC3A during HIV infection and pathogenesis, on the role of the cellular context in the regulation of the antiviral activities of members of the APOBEC3 family and more generally on the natural functions of APOBEC3A.     

A simple novel method for determining mortality rates in HIV treatment programs worldwide

In this Perspective, Gregory Bisson discusses a new article by Matthias Egger and colleagues that introduces a simple method for HIV treatment programs to more accurately estimate the proportion of patients dying in the first year after ART initiation.     

Functional identification of optimized RNAi triggers using a massively parallel sensor assay

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Highlights? The Sensor assay reliably identifies potent single-copy shRNAs ? Potent shRNAs are rare and generally not predicted by existing algorithms ? Analyses of ～20,000 shRNAs reveal insights into shRNA biogenesis and function ? Sensor-based rules provide a criteria framework for rational shRNA design     

Global variation in the piggyBac-like element of pink bollworm,Pectinophora gossypiella

The piggyBac transposable element, originally discovered in the cabbage looper, Trichoplusia ni, has been used widely in genetic engineering of insects including the pink bollworm, Pectinophora gossypiella, a major lepidopteran pest of cotton. Previously, we identified an intact copy of a piggyBac-like element (PLE) in pink bollworm, designated as PgPLE1.1. Here we report global variation in the occurrence and sequence of PgPLE1.1 and its flanking sequences. Low to high frequency of the PgPLE1.1 insertion was observed in populations from USA, Mexico, China, India, and Israel, while there is no PgPLE1.1 insertion in the populations from Australia. Investigation of the five haplotypes of PgPLE1.1, their frequency, and the flanking sequences of PgPLE1.1 revealed significant differences of the populations from Australia and China compared to other global populations, although recent occurrences of extensive gene flows among global populations were evident.     

Non-nearest-neighbor dependence of the stability for RNA group II single-nucleotide bulge loops

Thirty-one RNA duplexes containing single-nucleotide bulge loops were optically melted in 1 M NaCl, and the thermodynamic parameters ΔH°, ΔS°, ΔG°(37), and T(M) for each sequence were determined. The bulge loops were of the group II variety, where the bulged nucleotide is identical to one of its nearest neighbors, leading to ambiguity as to the exact position of the bulge. The data were used to develop a model to predict the free energy of an RNA duplex containing a single-nucleotide bulge. The destabilization of the duplex by the bulge was primarily related to the stability of the stems adjacent to the bulge. Specifically, there was a direct correlation between the destabilization of the duplex and the stability of the less stable duplex stem. Since there is an ambiguity of the bulge position for group II bulges, several different stem combinations are possible. The destabilization of group II bulge loops is similar to the destabilization of group I bulge loops, if the second least stable stem is used to predict the influence of the group II bulge. In-line structure probing of the group II bulge loop embedded in a hairpin indicates that the bulged nucleotide is the one positioned farther from the hairpin loop.     

Patellofemoral knee pain treatment using neuromuscular retraining of the hip musculature in an adolescent female: a case report

The purpose of this case study is to demonstrate the treatment of patella-femoral knee pain in an adolescent female athlete with emphasis on neuromuscular training of the knee and hip in synergy movement strategies. A 1.67-m, 61.5-kg, 15-year-old woman athlete reported to rehabilitation with the complaint of a 1-year history of bilateral knee pain. The patient noted that the symptoms were exacerbated with any sports-specific training. The patient played softball as an infielder. The athlete was referred by her family practice physician. After the patient was assessed, a clinical hypothesis was generated. It was thought that neuromuscular dysfunction of the hips and knees was causing faulty knee mechanics. These abnormal mechanics were presenting as patella-femoral knee pain. Initially, the athlete was assigned a home exercise program of side-lying hip abduction and lateral step-downs. At her first follow-up appointment, she noted increased symptoms that were aggravated with her home program. Upon inspecting her exercise technique, faulty step-down mechanics were contributing to her symptoms. Step-downs were discontinued, and the patient was instructed in and performed a chair squatting exercise, which was added to her home program. At her next follow-up, the patient noted being asymptomatic for 2 days. Her exercises were increased in intensity to include a Stairmaster and hip abduction and adduction on a 4-way hip machine. Eventually, over her treatment course, perturbation and proprioceptive training were initiated. By the sixth visit, the patient reported no symptoms and felt comfortable with self-management. A phone interview 3 months later indicated that the patient had no recurrent symptoms and was participating in sports without difficulty. This case demonstrates effectiveness of using hip and knee joint synergy to treat patella-femoral pain (PFP). The use of this synergy promotes proper patella–femoral alignment and improved knee mechanics. This case also is unique in the lack of physical agents and taping used to improve the patient's condition. It reinforces how exercise technique can carry over to functional athletic activities. This study provides a case for the use of hip and knee mechanical retraining in the treatment of PFP in adolescent female athletes who do not exhibit abnormal foot mechanics in weight bearing. It is important that sports medicine professionals be aware of these treatment options and are able to use them to correct these deficits in order to facilitate return to training and competition as quickly and safely as possible.     

Performance analysis of elite Rugby League match play using global positioning systems

The aim of this study was (a) to examine the physiological demands of competitive Rugby League match play using portable Global Positioning Systems (GPSs) to monitor players' movement patterns and heart rate (HR) and (b) examine positional comparisons to determine if players' physiological requirements are influenced by their playing position during Rugby League match play. Twenty-two elite male Rugby League players were monitored during 5 regular season competition matches using portable GPS software. There was no difference in the total distance traveled between backs (5,573 ± 1,128 m) and forwards (4,982 ± 1,185 m) during match play. Backs and forwards had an average HR of approximately 80% of their maximum (162 ± 11 and 165 ± 12 b · min(-1), respectively) throughout each match. Backs achieved greater maximum running speed (8.6 ± 0.7 m · s(-1)), completed a greater number of sprints (18 ± 6), had less time between sprints (3.2 ± 1.1 minutes), achieved a greater total duration of sprinting (44.7 ± 9.1 seconds), and covered more distance sprinting (321 ± 74 m) than forwards did (6.8 ± 0.7 m · s(-1), 11 ± 5, 5.2 ± 2.2 minutes, 25.8 ± 9.2 seconds, and 153 ± 38 m, respectively). The GPS successfully provided real-time feedback to identify significant positional differences in distances covered, running speed characteristics, and the physiological demands of competitive Rugby League match play.     

Temporal and Taxonomic Variability in Response of Fauna to Riparian Restoration

Evaluating the success of restoration projects requires well‐designed studies. Among the decisions that need to be made are what taxonomic groups to study and when to conduct the monitoring. To explore how these decisions can influence assessments of restoration success, we examined species richness and composition data collected over several years on different terrestrial fauna (landbirds, rodents, bees, and beetles) at Sacramento River restoration and remnant riparian sites. Our selection of study organisms enabled us to ask whether variability in species richness among restoration sites is less for vagile taxa than for sedentary taxa, and if invertebrates display greater variability among sites than vertebrates. Our results demonstrate that responses to restoration can vary depending upon the season when it is assessed, and the taxa that are studied. For all taxa except bees, there was considerable variability in the relative performance of taxa at restoration sites from one sampling date to the next, such that the relative ranking of the sites often changed dramatically. Comparisons of β ‐diversity (variability in species richness across sites) revealed that certain taxonomic groups were more spatially variable in their response to restoration than others. Among vertebrates, sedentary taxa (rodents) had significantly higher variability in species richness across sites than highly vagile taxa (birds); however, no such pattern was observed for invertebrates. Overall, vertebrates had lower variability than invertebrates, suggesting that evaluations of restoration success based on a few better‐known taxonomic groups (e.g., birds, rodents) may be inadequate to represent the biodiversity response of other groups (e.g., insects).     

The Lepidoptera of White Sands National Monument, Otero County, New Mexico, USA 4. A new species of Schinia Hübner, 1818 (Lepidoptera, Noctuidae, Heliothinae)

In 2006 the U.S. National Park Service initiated a long term study of the Lepidoptera at White Sands National Monument, Otero County, New Mexico. Schinia pogueisp. n., described here, was discovered in 2007, the second year of the study. The male and female adult moths and genitalia are illustrated.