West Nile Virus Genetic Diversity is Maintained during Transmission by Culex pipiens quinquefasciatus Mosquitoes

Due to error-prone replication, RNA viruses exist within hosts as a heterogeneous population of non-identical, but related viral variants. These populations may undergo bottlenecks during transmission that stochastically reduce variability leading to fitness declines. Such bottlenecks have been documented for several single-host RNA viruses, but their role in the population biology of obligate two-host viruses such as arthropod-borne viruses (arboviruses) in vivo is unclear, but of central importance in understanding arbovirus persistence and emergence. Therefore, we tracked the composition of West Nile virus (WNV; Flaviviridae, Flavivirus) populations during infection of the vector mosquito, Culex pipiens quinquefasciatus to determine whether WNV populations undergo bottlenecks during transmission by this host. Quantitative, qualitative and phylogenetic analyses of WNV sequences in mosquito midguts, hemolymph and saliva failed to document reductions in genetic diversity during mosquito infection. Further, migration analysis of individual viral variants revealed that while there was some evidence of compartmentalization, anatomical barriers do not impose genetic bottlenecks on WNV populations. Together, these data suggest that the complexity of WNV populations are not significantly diminished during the extrinsic incubation period of mosquitoes

A Parent Coach–Led Model of Well-Child Care for Young Children in Low-Income Communities: Protocol for a Cluster Randomized Controlled Trial

BackgroundThe Parent-focused Redesign for Encounters, Newborns to Toddlers (PARENT) intervention was created as a team-based approach to well-child care (WCC) that relies on a health educator (Parent Coach) to provide the bulk of WCC services, address specific needs faced by families in low-income communities, and decrease reliance on the clinician as the primary provider of WCC services. ObjectiveThis study aims to evaluate the impact of PARENT using a cluster randomized controlled trial. MethodsThis study tested the effectiveness of PARENT at 10 clinical sites in 2 federally qualified health centers in Tacoma, Washington, and Los Angeles, California. We conducted a cluster randomized controlled trial that included 916 families with children aged ≤12 months at the time of the baseline survey. Parents will be followed up at 6 and 12 months after enrollment. The Parent Coach, the main element of PARENT, provides anticipatory guidance, psychosocial screening and referral, developmental and behavioral surveillance, screening, and guidance at each WCC visit. The coach is supported by parent-focused previsit screening and visit prioritization, a brief, problem-focused clinician encounter for a physical examination and any concerns that require a clinician’s attention, and an automated text message parent reminder and education service for periodic, age-specific messages to reinforce key health-related information recommended by Bright Futures national guidelines. We will examine parent-reported quality of care (receipt of nationally recommended WCC services, family-centeredness of care, and parental experiences of care), and health care use (WCC, urgent care, emergency department, and hospitalizations), conduct a cost analysis, and conduct a separate time-motion study of clinician time allocation to assess efficiency. We will also collect data on exploratory measures of parent-and parenting-focused outcomes. Our primary outcomes were receipt of anticipatory guidance and emergency department use. ResultsParticipant recruitment began in March 2019. After recruitment, 6- and 12-month follow-up surveys will be completed. As of August 30, 2021, we enrolled a total of 916 participants. ConclusionsThis large pragmatic trial of PARENT in partnership with federally qualified health centers will assess its utility as an evidence-based and financially sustainable model for the delivery of preventive care services to children in low-income communities. Trial RegistrationClinicalTrials.gov: NCT03797898; https://clinicaltrials.gov/ct2/show/NCT03797898 International Registered Report Identifier (IRRID)DERR1-10.2196/2705

Dolutegravir (S/GSK1349572) Exhibits Significantly Slower Dissociation than Raltegravir and Elvitegravir from Wild-Type and Integrase Inhibitor-Resistant HIV-1 Integrase-DNA Complexes▿†

The integrase inhibitor (INI) dolutegravir (DTG; S/GSK1349572) has significant activity against HIV-1 isolates with raltegravir (RAL)- and elvitegravir (ELV)-associated resistance mutations. As an initial step in characterizing the different resistance profiles of DTG, RAL, and ELV, we determined the dissociation rates of these INIs with integrase (IN)-DNA complexes containing a broad panel of IN proteins, including IN substitutions corresponding to signature RAL and ELV resistance mutations. DTG dissociates slowly from a wild-type IN-DNA complex at 37°C with an off-rate of 2.7 × 10−6 s−1 and a dissociative half-life (t1/2) of 71 h, significantly longer than the half-lives for RAL (8.8 h) and ELV (2.7 h). Prolonged binding (t1/2, at least 5 h) was observed for DTG with IN-DNA complexes containing E92, Y143, Q148, and N155 substitutions. The addition of a second substitution to either Q148 or N155 typically resulted in an increase in the off-rate compared to that with the single substitution. For all of the IN substitutions tested, the off-rate of DTG from IN-DNA complexes was significantly slower (from 5 to 40 times slower) than the off-rate of RAL or ELV. These data are consistent with the potential for DTG to have a higher genetic barrier to resistance, provide evidence that the INI off-rate may be an important component of the mechanism of INI resistance, and suggest that the slow dissociation of DTG may contribute to its distinctive resistance profile

High-dose chemotherapy with stem cell rescue as initial therapy for anaplastic oligodendroglioma: Long-term follow-up

We previously reported a phase 2 trial of 69 patients with newly diagnosed anaplastic or aggressive oligodendroglioma who were treated with intensive procarbazine, CCNU (lomustine), and vincristine (PCV) followed by high-dose thiotepa with autologous stem cell rescue. This report summarizes the long-term follow-up of the cohort of 39 patients who received high-dose thiotepa with autologous stem cell support. Thirty-nine patients with a median age of 43 (range, 18–67) and a median KPS of 100 (range, 70–100) were treated. Surviving patients now have a median follow-up of 80.5 months (range, 44–142). The median progression-free survival is 78 months, and median overall survival has not been reached. Eighteen patients (46%) have relapsed. Neither histology nor prior low-grade oligodendroglioma correlated with risk of relapse. Persistent nonenhancing tumor at transplant was identified in our initial report as a significant risk factor for relapse; however, long-term follow-up has not confirmed this finding. Long-term neurotoxicity has developed only in those patients whose disease relapsed and required additional therapy; no patient in continuous remission has developed a delayed neurologic injury. This treatment strategy affords long-term disease control to a subset of patients with newly diagnosed anaplastic oligodendroglioma without evidence of delayed neurotoxicity or myelodysplasia