The role of de novo mutations (DNMs) in common diseases remains largely unknown. Nonetheless, the rate of de novo deleterious mutations and the strength of selection against de novo mutations are ...critical to understanding the genetic architecture of a disease. Discovery of high-impact DNMs requires substantial high-resolution interrogation of partial or complete genomes of families via resequencing. We hypothesized that deleterious DNMs may play a role in cases of autism spectrum disorders (ASD) and schizophrenia (SCZ), two etiologically heterogeneous disorders with significantly reduced reproductive fitness. We present a direct measure of the de novo mutation rate (μ) and selective constraints from DNMs estimated from a deep resequencing data set generated from a large cohort of ASD and SCZ cases (n = 285) and population control individuals (n = 285) with available parental DNA. A survey of ∼430 Mb of DNA from 401 synapse-expressed genes across all cases and 25 Mb of DNA in controls found 28 candidate DNMs, 13 of which were cell line artifacts. Our calculated direct neutral mutation rate (1.36 × 10−8) is similar to previous indirect estimates, but we observed a significant excess of potentially deleterious DNMs in ASD and SCZ individuals. Our results emphasize the importance of DNMs as genetic mechanisms in ASD and SCZ and the limitations of using DNA from archived cell lines to identify functional variants.
In most male birds that exhibit paternal care, extending the spring testosterone (T) peak throughout the breeding season reduces nestling provisioning. However, in some species, this trade-off ...between high T and expression of paternal care is absent. For example, during some or all of the nestling period, T did not affect paternal behavior in Male Lapland longspurs (
Calcarius lapponicus), chestnut-collared longspurs (
Calcarius ornatus), and great tits (
Parus major). Two ecological constraints have been hypothesized to drive insensitivity to T after eggs hatch: (1) a short breeding season that limits breeding opportunities, and (2) a need for paternal care to ensure reproductive success. However, because two of the three species that exhibit T insensitivity are closely related, potential phylogenetic confounds limit determination of which, if either, factor constrains some males to T insensitivity. We examined the effects of supplementary T on paternal behavior in the Snow Bunting (
Plectrophenax nivalis), a member of the monophyletic
Calcarius/
Plectrophenax clade. Male Snow Buntings are constrained to a short breeding season, but paternal care is not essential for survival of nestlings. We administered exogenous T during the parental phase to mimic the early spring T peak. T treatment increased song rates and interfered with paternal behavior such that nestlings of T-implanted males grew more slowly than controls. Our data suggest that T insensitivity in this clade is related to relatively recent constraints of the breeding environment (i.e., not simply common ancestry) and that the necessity of paternal care in some species may be a strong selective factor driving behavioral insensitivity to T during the parental phase.
The growing use of newer communication and Internet technologies, even among low-income and transient populations, require research staff to update their outreach strategies to ensure high follow-up ...and participant retention rates. This paper presents the views of research assistants on the use of cell phones and the Internet to track participants in a multisite randomized trial of substance use disorder treatment.
Preinterview questionnaires exploring tracking and other study-related activities were collected from 21 research staff across the 10 participating US sites. Data were then used to construct a semistructured interview guide that, in turn, was used to interview 12 of the same staff members. The questionnaires and interview data were entered in Atlas.ti and analyzed for emergent themes related to the use of technology for participant-tracking purposes.
Study staff reported that most participants had cell phones, despite having unstable physical addresses and landlines. The incoming call feature of most cell phones was useful for participants and research staff alike, and texting proved to have additional benefits. However, reliance on participants' cell phones also proved problematic. Even homeless participants were found to have access to the Internet through public libraries and could respond to study staff e-mails. Some study sites opened generic social media accounts, through which study staff sent private messages to participants. However, the institutional review board (IRB) approval process for tracking participants using social media at some sites was prohibitively lengthy. Internet searches through Google, national paid databases, obituaries, and judiciary Web sites were also helpful tools.
Research staff perceive that cell phones, Internet searches, and social networking sites were effective tools to achieve high follow-up rates in drug abuse research. Studies should incorporate cell phone, texting, and social network Web site information on locator forms; obtain IRB approval for contacting participants using social networking Web sites; and include Web searches, texting, and the use of social media in staff training as standard operating procedures.
Direct-acting antivirals (DAAs) are highly effective for treating HCV infection even among people who inject drugs (PWID). Yet, little is known about patients' adherence patterns and their ...association with sustained virologic response (SVR) rates. We aimed to summarize various adherence patterns and determine their associations with SVR.
Electronic blister packs were used to measure daily adherence to once-a-day sofosbuvir/velpatasvir during the 12-week treatment period among active PWIDs. Blister pack data were available for 496 participants who initiated DAAs for whom SVR status was known. Adherence was summarized in multiple patterns, such as total adherent days, consecutive missed days, and early discontinuations. Thresholds for adherence patterns associated with >90% SVR rates were also determined.
The overall SVR rate was 92.7%, with a median adherence rate of 75%. All adherence patterns indicating greater adherence were significantly associated with achieving SVR. Participant groups with ≥50% (>42/84) adherent days or <26 consecutive missed days achieved an SVR rate of >90%. Greater total adherent days during 9-12 weeks and no early discontinuation were significantly associated with higher SVR rates only in those with <50% adherence. Participants with first month discontinuation and ≥2 weeks of treatment interruption had low SVR rates, 25% and 85%, respectively. However, greater adherent days were significantly associated with SVR (adjusted odds ratio 1.10; 95% CI 1.04–1.16; p <0.001) even among participants with ≥14 consecutive missed days.
High SVR rates can be achieved in the PWID population despite suboptimal adherence. Encouraging patients to take as much medication as possible, with <2 weeks consecutive missed days and without early discontinuation, was found to be important for achieving SVR.
People who inject drugs can be cured of HCV in >90% of cases, even with relatively low adherence to direct-acting antivirals, but early discontinuations and long treatment interruptions can significantly reduce the likelihood of achieving cure. Clinicians should encourage people who inject drugs who are living with HCV to adhere daily to direct-acting antivirals as consistently as possible, but if any days are interrupted, to continue and complete treatment. These results from the HERO study are important for patients living with HCV, clinicians, experts writing clinical guidelines, and payers.
NCT02824640.
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•The recent US nationwide HERO RCT study randomized 755 PWIDs living with HCV.•Electronic blister packs measured day-by-day adherence to 12-week DAA regimen.•Greater adherence is associated with SVR among those with <50% adherence rate.•Treatment interruption and early discontinuation are associated with lower SVR.•High SVR (>90%) can be achieved even with adherence as low as 50%.
The neuromodulator serotonin is an important regulator of aggressive behavior in vertebrates. Experimentally increasing synaptic levels of serotonin with fluoxetine, a selective serotonin reuptake ...inhibitor, has been shown to reliably decrease the expression of aggressive behavior. Here, we describe a method by which fluoxetine can be noninvasively administered to male Betta splendens (an attractive model for the study of aggressive behavior) and describe a simple laboratory exercise that allows students to experimentally investigate the physiological mechanisms of aggressive behavior. We demonstrate that relatively short-term exposure (3 h) of male bettas to as little as 3 microg/ml of fluoxetine-treated aquarium water is sufficient to reduce the expression of specific aggressive behaviors. We emphasize the physiological concepts that can be addressed with this exercise, including the role of the serotonergic system in regulating aggression, and the interplay of environmental contaminants and physiology in regulating the expression of behavior. We also highlight important aspects of experimental design. This exercise can be flexibly altered to accommodate one or several laboratory periods. It is also low cost, is low impact to the animals, and requires minimal preparation time for instructors.
There is concern that P from dairy effluent sprayfields will leach into groundwater beneath Suwannee River basins in northern Florida. Our purpose was to describe the effects of dairy effluent ...irrigation on the movement of soil P and other nutrients within the upper soil profile of a sprayfield over three 12-mo cycles (April 1998-March 2001). Effluent P rates of 70, 110, and 165 kg ha-1 cycle-1 were applied to forages that were grown year-round. The soil is a deep, excessively drained sand (thermic, uncoated Typic Quartzipsamment). Mean P concentration in soil water below the rooting zone (152-cm depth) was <or= 0.1 mg L-1 during 11 3-mo periods. Mehlich-1-extractable (M1) P, Al, and Ca in the topsoil increased over time but did not change in subsoil depths of 25 to 51, 51 to 71, 71 to 97, and 97 to 122 cm. Topsoil Ca increased as effluent rate increased. High Ca levels were found in dairy effluent (avg.: 305 mg L-1) and supplemental irrigation water (avg.: 145 mg L-1) which likely played a role in retaining P in the topsoil. An effect of effluent rate on P and Al concentrations in the topsoil was not detected, probably due to large and variable quantities present at project initiation. The P retention capacity (i.e., Al plus Fe) increased in the topsoil because Al increased. Dairy effluent contained Al (avg.: 31 mg L-1). Phosphorus saturation ratio (PSR) increased over time in the topsoil but not in subsoil layers. Regardless of effluent rate, the P retention capacity and PSR of subsoil, which contained 119 to 229 mg kg-1 of Al, should be taken into account when assessing the risk of P moving below the rooting zone of most forage crops.
This article describes the essential components for effective and comprehensive HIV care for youth who have tested positive and have been linked to HIV treatment. Descriptive profile data are also ...presented that detail the demographics, risk behaviors and health care barriers of youth served in the five Special Projects of National Significance (SPNS), which focused on adolescents and young adults.
Data presented are from the core multi-site data set, which was standardized across the five youth-oriented SPNS projects. Substance use and mental health symptoms were gathered using the Personal Problem Questionnaire (PPQ) screener, which was an adaptation of the PRIME-MD. In-depth qualitative interviews with enrolled HIV-positive youth were also conducted by several Projects.
Medical care alone is not enough and cannot be effective without supportive program components such as flexible scheduling, and a multi-disciplinary team approach that includes assertive case management. Case Managers help enrolled youth with concrete service needs such as housing, emergency financial assistance for food/utilities, transportation, child care, coverage for prescriptions, and public entitlements. They also help isolated youth to connect with a personal support system. Addressing those needs helps to facilitate and reinforce treatment adherence and retention. In addition to other identified needs such as stable housing and transportation, a significant number of enrolled youth self-reported having experienced physical, sexual, and/or emotional abuse in their lives and articulated a need for mental health services. Therefore, effective HIV care for youth must be multi-faceted; it must consist of more than a medical component.
Abstract
Background
ADG20 is a fully human IgG1 monoclonal antibody engineered to have potent and broad neutralization against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other ...SARS-like CoVs with pandemic potential as well as an extended-half-life. ADG20 is administered intramuscularly (IM). A QSP/PBPK model was constructed to support dose selection for a COVID-19 Phase 2/3 prevention trial (EVADE: NCT04859517).
Methods
A QSP/PBPK model and a CDC reference adult body weight distribution (45–150 kg) were used to simulate 1000 concentration-time profiles for candidate single-dose regimens of ADG20 (150–450 mg IM). As serum virus neutralizing antibody (sVNA) titers are reportedly a key correlate of protection from COVID-19, a regression equation between time-matched serum ADG20 concentrations (following a 300 mg IM dose) and sVNA titers was developed using measured titers against authentic SARS-CoV-2 determined by a plaque reduction neutralization assay. Projected ADG20 serum concentrations relative to neutralization potency in vitro (90% inhibitory concentration IC90) for authentic SARS-CoV-2 were also evaluated.
Results
The measured 50% neutralization titer (MN50; geometric mean coefficient of variation, %) was 1382 (32.7%) 13 days after a single 300 mg IM dose of ADG20. This was within the range of peak sVNA titers reported for COVID-19 vaccine recipients. Using the linear equation relating serum ADG20 concentration to time matched individual MN50 titers and the QSP/PBPK median PK prediction, the anticipated median MN50 exceeded the threshold for protection from SARS-CoV-2 infection established in a non-human primate adoptive transfer model for up to 52 weeks. Based on the QSP/PBPK median PK prediction, median ADG20 serum concentrations are projected to remain >100-fold above the ADG20 IC90 value of 0.011 mg/L against authentic SARS-CoV-2 for up to 52 weeks (Figure).
Conclusion
Following administration of a single 300 mg IM dose, sVNA titers and concentrations of ADG20 are projected to remain above thresholds anticipated to be required for protection against COVID-19 for up to 52 weeks. These data support the evaluation of a single ADG20 300 mg IM dose for the prevention of COVID-19.
Figure. QSP/PBPK model forecast of ADG20 300 mg IM in adults.
Predicted median serum ADG20 concentration is shown with the dotted line representing 100× in vitro IC90 of 0.011 mg/L or 1.1 mg/L; the solid black line represents the simulated median; the shaded area represents the 90% prediction interval. The predicted median half-life of ADG20 300 mg IM exceeded 74 days. PBPK model inputs include Ln-normal Kd,FcRn of 9.55 nM (10% IIV); IM bioavailability of 100%; 15% IIV on muscle lymph RC; and Centers for Disease Control and Prevention weight distribution of 45–150 kg. FcRn, neonatal Fc receptor; IIV, inter-individual variability; Kd, dissociation constant; Ln, log-normal; RC, reflection coefficient.
Disclosures
Scott A. Van Wart, PhD, Adagio Therapeutics, Inc. (Independent Contractor) Evan D. Tarbell, PhD, Adagio Therapeutics, Inc. (Independent Contractor) Kristin Narayan, PhD, Adagio Therapeutics, Inc. (Employee) Laura M. Walker, PhD, Adagio Therapeutics, Inc. (Other Financial or Material Support, Laura M. Walker is an inventor on a patent application submitted by Adagio Therapeutics, Inc., describing the engineered SARS-CoV-2 antibody.) Lynn E. Connolly, MD, PhD, Adagio Therapeutics, Inc. (Employee) Paul G. Ambrose, PharmD, Adagio Therapeutics, Inc. (Employee)
To demonstrate that whereas all HIV-infected youth evidence complex factors that challenge retention in care and adherence to treatment, HIV-infected females have additional issues that are ...gender-specific.
Preliminary data from a subset of 21 adolescent/young women under age 25 from the Whole Life mental health-perinatal HIV care project were analyzed to illustrate the needs of these patients.
Of the 21 young women assessed, all but one was of minority background, and a sizeable majority had limited education (<high school diploma) and were quite poor (incomes <$500/mo.). Nearly 67% first learned of their HIV status between ages 16 and 19 years. More than three-fourths were pregnant and, of these, more than one-third entered prenatal care in the last trimester. More than half had responsibility for one to two other children. Two-thirds reported having unprotected sex in the prior 6 months. Nearly 43% had CD4 counts of 500 or below. About one-third screened positive for a mental health problem, and the majority reported a striking frequency of exposure to abusive events and traumatic losses across their short lifetimes.
Adolescent girls and young women have unique needs for developmentally appropriate medical and psychosocial approaches to promote retention and adherence.
Abstract
Background
ADG20 is a fully human IgG1 monoclonal antibody engineered to have potent and broad neutralization against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and other ...SARS-like CoVs with pandemic potential and an extended half-life. ADG20 is administered intramuscularly (IM). A QSP/PBPK model was constructed to support dose selection for a Phase 2/3 trial of ambulatory patients with mild to moderate COVID-19 (STAMP: NCT04805671).
Methods
A QSP/PBPK model was used to simulate receptor occupancy (RO) and drug exposure in the upper airway (nasopharyngeal/oropharyngeal epithelial lining fluid ELF compartment). RO was linked to an existing viral dynamic model to enable the prediction of the natural time course of viral load and the effect of ADG20 on viral clearance and infectivity rate. RO was calculated using: 1) in vitro ADG20–SARS-CoV-2 binding kinetics (association rate constant (kon) of 1.52E+06 M-1•s1 and dissociation rate constant (koff) of 2.81E-04 s-1 from a Biacore assay; 2) time course of ADG20 concentrations in ELF; and 3) time course of viral load following ADG20 administration. Molar SARS-CoV-2 viral binding site capacity was calculated assuming 40 spike proteins per virion, 3 binding sites per spike, and an initial viral load of log 107 copies/mL for all patients. The QSP/PBPK model and a 2018 CDC reference body weight distribution (45–150 kg) were used to simulate 1000 concentration-time profiles for a range of candidate ADG20 regimens. ADG20 regimens were evaluated against 2 criteria: 1) ability to attain near complete ( >90%), and durable (28-day) SARS-CoV-2 RO in the ELF; and 2) ability to maintain ELF ADG20 concentrations relative to a concentration (0.5 mg/L) associated with 100% viral growth suppression in an in vitro post-infection assay.
Results
A single 300 mg IM ADG20 dose met the dose selection criteria in terms of RO (Figure A) and viral growth suppression (Figure B).
Conclusion
These data support the evaluation of an ADG20 300 mg IM dose for the treatment of mild to moderate COVID-19. ADG20 is forecasted to attain near complete ( >90%) SARS-CoV-2 RO in the ELF and maintain ELF ADG20 concentrations above that associated with 100% viral growth suppression in vitro.
Figure. QSP/PBPK model forecast of ADG20 300 mg IM in adults
(A) Predicted RO expressed as percent occupancy with the dotted line representing the threshold for 90% RO. (B) Predicted median concentration of ADG20 relative to a concentration (0.5 mg/L) associated with 100% viral growth suppression as indicated by the dotted line; the shaded area represents the 90% prediction interval.
Disclosures
Evan D. Tarbell, PhD, Adagio Therapeutics, Inc. (Independent Contractor) Scott A. Van Wart, PhD, Adagio Therapeutics, Inc. (Independent Contractor) Laura M. Walker, PhD, Adagio Therapeutics, Inc. (Other Financial or Material Support, Laura M. Walker is an inventor on a patent application submitted by Adagio Therapeutics, Inc., describing the engineered SARS-CoV-2 antibody.) Andrew Santulli, PhD, Adagio Therapeutics, Inc. (Independent Contractor) Lynn E. Connolly, MD, PhD, Adagio Therapeutics, Inc. (Employee) Donald E Mager, PharmD, PhD, Adagio Therapeutics, Inc. (Independent Contractor) Paul G. Ambrose, PharmD, Adagio Therapeutics, Inc. (Employee)
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