Design of paediatric trials with benefit-risk endpoints using a composite score of adverse events of interest (AEI) and win-statistics.

A fundamental problem in the regulatory evaluation of a therapy is assessing whether the benefit outweighs the associated risks. This work proposes designing a trial that assesses a composite endpoint consisting of benefit and risk, hence, making the core of the design of the study, to assess benefit and risk. The proposed benefit risk measure consists of efficacy measure(s) and a risk measure that is based on a composite score obtained from pre-defined adverse events of interest (AEI). This composite score incorporates full aspects of adverse events of interest (i.e. the incidence, severity, and duration of the events). We call this newly proposed score the AEI composite score. After specifying the priorities between the components of the composite endpoint, a win-statistic (i.e. win ratio, win odds, or net benefit) is used to assess the difference between treatments in this composite endpoint. The power and sample size requirements of such a trial design are explored via simulation. Finally, using Dupixent published adult study results, we show how we can design a paediatric trial where the primary outcome is a composite of prioritized outcomes consisting of efficacy endpoints and the AEI composite score endpoint. The resulting trial design can potentially substantially reduce sample size compared to a trial designed to assess the co-primary efficacy endpoints, therefore it may address the challenge of slow enrollment and patient availability for paediatric studies.

Communicating risk to promote colorectal cancer screening: a multi-method study to test tailored versus targeted message strategies.

Colorectal cancer (CRC) screening rates are suboptimal, partly due to poor communication about CRC risk. More effective methods are needed to educate patients, but little research has examined best practices for communicating CRC risk. This multi-method study tests whether tailoring CRC risk information increases screening intentions. Participants (N = 738) were randomized with a 2:2:1 allocation to tailored, targeted, and control message conditions. The primary outcome was intention to screen for CRC (yes/no). Additional variables include perceived message relevance, perceived susceptibility to CRC, and free-text comments evaluating the intervention. A chi-square test determined differences in the proportion of participants who intended to complete CRC screening by condition. A logistic-based path analysis explored mediation. Free-text comments were analyzed using advanced topic modeling analysis. CRC screening intentions were highest in the tailored intervention and significantly greater than control (P = 0.006). The tailored message condition significantly increased message relevance compared with control (P = 0.027) and targeted conditions (P = 0.002). The tailored condition also increased susceptibility (P < 0.001) compared with control, which mediated the relationship between the tailored condition and intention to screen (b = 0.04, SE = 0.02, 95% confidence interval = 0.02, 0.09). The qualitative data reflect similar trends. The theoretical mechanisms and practical implications of tailoring health education materials about CRC risk are discussed.

Case Report of Intractable Vomiting and Abdominal Pain Related to Heavy Daily Cannabis Use.

CASE: A highly anxious and dehydrated adolescent came to a local emergency department with complaints of intractable emesis, weight loss, and abdominal pain. He stated that bathing and "guzzling water" ameliorated symptoms. He admitted to using marijuana socially. Efforts at palliation with benzodiazepines, atypical antipsychotics, and antiemetic medications were unable to soothe the patient. After thorough initial diagnostics and physical exam failed to elucidate etiology, the patient was referred to an inpatient psychiatric facility for further evaluation of potential psychosomatic or affective causes. During psychiatric evaluation and upon obtaining additional information from family and reviewing the work done by primary care providers, the patient was questioned stringently about his marijuana use patterns. Questioning revealed that the patient had previous chemical dependency treatment, legal charges related to drug use, and heavy daily marijuana use including "dabbing," ingestion of THC candy, and smoking up to several grams a day. DISCUSSION: Cannabinoid hyperemesis syndrome (CHS) consists of intractable emesis, abdominal pain, and weight loss. There is often a history of symptom amelioration with bathing and showering. These patients may or may not admit to heavy marijuana use. Cannabis effects vary and are dose dependent. Historically, CHS would require over a year of heavy daily use. In this day and age of higher THC potency marijuana and even higher THC potency "dabs," it is anticipated that more cases of cannabis related syndromes in general, and CHS in particular will be presenting more frequently to ambulatory and emergency room settings. The patients will potentially be younger and have a shorter duration of heavy cannabis use before symptoms start. A high index of suspicion will be required to prevent expensive and potentially invasive workups and thus delaying diagnosis and treatment.

Improving the Utilization of STRmix™ Variance Parameters as Semi-Quantitative Profile Modeling Metrics.

Distributions of the variance parameter values developed during the validation process. Comparisons of these prior distributions to the run-specific average are one measure used by analysts to assess the reliability of a STRmix deconvolution. This study examined the behavior of three different STRmix variance parameters under standard amplification and interpretation conditions, as well as under a variety of challenging conditions, with the goal of making comparisons to the prior distributions more practical and meaningful. Using information found in STRmix v2.8 Interpretation Reports, we plotted the log10 of each variance parameter against the log10 of the template amount of the highest-level contributor (Tc) for a large set of mixture data amplified under standard conditions. We observed nonlinear trends in these plots, which we regressed to fourth-order polynomials, and used the regression data to establish typical ranges for the variance parameters over the Tc range. We then compared the typical variance parameter ranges to log10(variance parameter) v log10(Tc) plots for mixtures amplified and interpreted under a variety of challenging conditions. We observed several distinct patterns to variance parameter shifts in the challenged data interpretations in comparison to the unchallenged data interpretations, as well as distinct shifts in the unchallenged variance parameters away from their prior gamma distribution modes over specific ranges of Tc. These findings suggest that employing empirically determined working ranges for variance parameters may be an improved means of detecting whether aberrations in the interpretation were meaningful enough to trigger greater scrutiny of the electropherogram and genotype interpretation.

Compound and Conditioned Likelihood Ratio Behavior within a Probabilistic Genotyping Context.

In cases where multiple questioned individuals are separately supported as contributors to a mixed DNA profile, guidance documents recommend performing a comparison to see if there is support for their joint contribution. Anecdotal observations suggest the summed log of the individual likelihood ratios (LR), termed the simple LR product, should be roughly equivalent to or less than the log(LR) for the joint likelihood ratio, termed the compound LR. To assist casework analysts in evaluating statistical weights applied to a case at hand, this study assessed how consistently compound LRs conform to an additive behavior when compared to the simple LR product counterparts. Two-, three-, and four-person DNA mixture data, of various mixture proportions and DNA inputs, were interpreted by STRmix® version 2.8 Probabilistic Genotyping Software. Relative magnitudes of LR increases were found to be dependent on both template level and mixture composition. The distribution of log(LR) differences between all compound/simple LR comparisons was ~-2.7 to ~28.3. This level of information gain was similar to that for compound LR comparisons, with and without interpretation conditioning (~-3.2 to ~27.7). In both scenarios, the probability density peaked at approximately 0.5, indicating the information gain from constrained genotype combinations has a comparable impact on the outcome of LR calculations whether the restriction is applied before or after interpretation.

Telehealth and racial disparities in colorectal cancer screening: A pilot study of how virtual clinician characteristics influence screening intentions.

Introduction: Racial disparities in colorectal cancer (CRC) can be addressed through increased adherence to screening guidelines. In real-life encounters, patients may be more willing to follow screening recommendations delivered by a race concordant clinician. The growth of telehealth to deliver care provides an opportunity to explore whether these effects translate to a virtual setting. The primary purpose of this pilot study is to explore the relationships between virtual clinician (VC) characteristics and CRC screening intentions after engagement with a telehealth intervention leveraging technology to deliver tailored CRC prevention messaging. Methods: Using a posttest-only design with three factors (VC race-matching, VC gender, intervention type), participants (N = 2267) were randomised to one of eight intervention treatments. Participants self-reported perceptions and behavioral intentions. Results: The benefits of matching participants with a racially similar VC trended positive but did not reach statistical significance. Specifically, race-matching positively influenced screening intentions for Black participants but not for Whites (b = 0.29, p = 0.10). Importantly, perceptions of credibility, attractiveness, and message relevance significantly influenced screening intentions and the relationship with race-matching. Conclusions: To reduce racial CRC screening disparities, investments are needed to identify patient-focused interventions to address structural barriers to screening. This study suggests that telehealth interventions that match Black patients with a Black VC can enhance perceptions of credibility and message relevance, which may then improve screening intentions. Future research is needed to examine how to increase VC credibility and attractiveness, as well as message relevance without race-matching.

Can virtual human clinicians help close the gap in colorectal cancer screening for rural adults in the United States? The influence of rural identity on perceptions of virtual human clinicians.

Rural adults experience disparities in colorectal cancer screening, a trend even more distinct among rural Black adults. Healthcare disruptions caused by COVID-19 exacerbated inequities, heightening attention on virtual communication strategies to increase screening. Yet little is known about how rural adults perceive virtual human clinicians (VHCs). Given that identifying as rural influences perceived source credibility often through appearance judgments, the goal of this pilot was to explore how to develop VHCs that individuals highly identified with rurality find attractive. Between November 2018 and April 2019, we tested a culturally tailored, VHC-led telehealth intervention delivering evidence-based colorectal cancer prevention education with White and Black adults (N = 2079) in the United States recruited through an online panel who were non-adherent to screening guidelines and between 50 and 73 years of age. Participants were randomized on three factors (VHC race-matching, VHC gender-matching, Intervention type). Ordinal logistic regression models examined VHC appearance ratings. Participants with a high rural identity (AOR = 1.12, CI = [1.02, 1.23], p =.02) rated the VHCs more attractive. High rural belonging influenced VHC attractiveness for Black participants (AOR = 1.22, CI = [1.03, 1.44], p =.02). Also, Black participants interacting with a Black VHC and reporting high rural self-concept rated the VHC as more attractive (AOR = 2.22, CI = [1.27, 3.91], p =.01). Findings suggest adults for whom rural identity is important have more positive impressions of VHC attractiveness. For patients with strong rural identities, enhancing VHC appearance is critical to tailoring colorectal cancer prevention interventions.

A Pilot Study Examining the Efficacy of Delivering Colorectal Cancer Screening Messages via Virtual Health Assistants.

INTRODUCTION: Patients are more likely to complete colorectal cancer screening when recommended by a race-concordant healthcare provider. Leveraging virtual healthcare assistants to deliver tailored screening interventions may promote adherence to colorectal cancer screening guidelines among diverse patient populations. The purpose of this pilot study is to determine the efficacy of the Agent Leveraging Empathy for eXams virtual healthcare assistant intervention to increase patient intentions to talk to their doctor about colorectal cancer screening. It also examines the influence of animation and race concordance on intentions to complete colorectal cancer screening. METHODS: White and Black adults (N=1,363) aged 50-73 years and not adherent to colorectal cancer screening guidelines were recruited from Qualtrics Panels in 2018 to participate in a 3-arm (animated virtual healthcare assistant, static virtual healthcare assistant, attention control) message design experiment. In 2020, a probit regression model was used to identify the intervention effects. RESULTS: Participants assigned to the animated virtual healthcare assistant (p<0.01) reported higher intentions to talk to their doctor about colorectal cancer screening than participants assigned to the other conditions. There was a significant effect of race concordance on colorectal cancer screening intentions but only in the static virtual healthcare assistant condition (p=0.04). Participant race, age, trust in healthcare providers, health literacy, and cancer information overload were also significant predictors of colorectal cancer screening intentions. CONCLUSIONS: Animated virtual healthcare assistants were efficacious compared with the static virtual healthcare assistant and attention control conditions. The influence of race concordance between source and participant was inconsistent across conditions. This warrants additional investigation in future studies given the potential for virtual healthcare assistant‒assisted interventions to promote colorectal cancer screening within guidelines.

Systematic evaluation of STRmix™ performance on degraded DNA profile data.

This study examined the DNA degradation modeling capacity of STRmix™, a widely implemented DNA interpretation software program. As a part of the CAL DOJ STRmix™ v2.4 validation, a large volume of STR profile data was generated from intact template DNA exposed to DNase I for a series of increasing time intervals. The resulting degraded profile data was analyzed with STRmix™ v2.4, and the efficacy of the analysis was assessed, both in terms of how the degradation modeling parameter values from the STRmix™ analysis compared to ground truth values, and how the weight-of-evidence statistics calculated for degraded profiles compared to those calculated for corresponding intact profiles. An additional set of differentially degraded mixture data was generated in silico to further challenge the STRmix™ degradation model, as well as to determine the extent to which end-user adjustment of the model's application can assist in resolving analysis problems that arise when high levels of degradation are observed in a profile. This work demonstrates that the degradation model in STRmix™ is capable of addressing a wide range of degraded STR profile data. The assessment expands the range of samples that have been rigorously examined using probabilistic genotyping approaches, as called for by forensic advisory bodies such as the United States President's Council of Advisors on Science and Technology.

A sensitivity analysis to determine the robustness of STRmix™ with respect to laboratory calibration.

STRmix™ uses several laboratory specific parameters to calibrate the stochastic model for peak heights. These are modelled on empirical observations specific to the instruments and protocol used in the analysis. The extent to which these parameters can be borrowed from laboratories with similar technology and protocols without affecting the accuracy of the system is investigated using a sensitivity analysis. Parameters are first calibrated to a publicly available dataset, after which a large number of likelihood ratios are computed for true contributors and non-contributors using both the calibrated parameters and several borrowed parameters. Differences in the LR caused by using different sets of parameter values are found to be negligible.

Transcriptional profile of aging in C. elegans.

BACKGROUND: Numerous gerontogene mutants leading to dramatic life extensions have been identified in the nematode Caenorhabditis elegans over the last 20 years. Analysis of these mutants has provided a basis for understanding the mechanisms driving the aging process(es). Several distinct mechanisms including an altered rate of aging, increased resistance to stress, decreased metabolic rate, or alterations in a program causing organismic aging and death have been proposed to underlie these mutants. RESULTS: Whole-genome analysis of gene expression during chronological aging of the worm provides a rich database of age-specific changes in gene expression and represents one way to distinguish among these models. Using a rigorous statistical model with multiple replicates, we find that a relatively small number of genes (only 164) show statistically significant changes in transcript levels as aging occurs (<1% of the genome). Expression of heat shock proteins decreases, while expression of certain transposases increases in older worms, and these findings are consistent with a higher mortality risk due to a failure in homeostenosis and destabilization of the genome in older animals. Finally, a specific subset of genes is coordinately altered both during chronological aging and in the transition from the reproductive form to the dauer, demonstrating a mechanistic overlap in aging between these two processes. CONCLUSIONS: We have performed a whole-genome analysis of changes in gene expression during aging in C. elegans that provides a molecular description of C. elegans senescence.

Gene expression analysis in a transgenic Caenorhabditis elegans Alzheimer's disease model.

We have engineered transgenic Caenorhabditis elegans animals to inducibly express the human beta amyloid peptide (Abeta). Gene expression changes resulting from Abeta induction have been monitored by cDNA hybridization to glass slide microarrays containing probes for almost all known or predicted C. elegans genes. Using statistical criteria, we have identified 67 up-regulated and 240 down-regulated genes. Subsets of these regulated genes have been tested and confirmed by quantitative RT-PCR. To investigate whether genes identified in this model system also show gene expression changes in Alzheimer's disease (AD) brain, we have also used quantitative RT-PCR to examine in post-mortem AD brain tissue transcript levels of alphaB-crystallin (CRYAB) and tumor necrosis factor-induced protein 1 (TNFAIP1), human homologs of genes found to be robustly induced in the transgenic C. elegans model. Both CRYAB and TNFAIP1 show increased transcript levels in AD brains, supporting the validity of this approach.

Degradation of N-acylhomoserine lactones, the bacterial quorum-sensing molecules, by acylase.

Porcine kidney acylase I was shown to be able to deacylate N-acylhomoserine lactones, a family of chemicals employed by Gram-negative bacteria as quorum-sensing molecules for cell population density-dependent growth (such as biofilm formation). The enzyme transformed both N-butyryl-and N-octanoyl-L-homoserine lactones into L-homoserine. An optimal pH of 10 at 23 degrees C and an optimal temperature of 76 degrees C at pH 9 were found for the enzyme in hydrolyzing N-butyryl-homoserine lactone. At pH 9 and 23 degrees C, the enzymatic catalysis had a K(m) of 81+/-3 mM and a k(cat) of 127+/-2 nmol min(-1) per mg. The enzyme was also shown to be able to reduce the biofilm growth in an aquarium water sample. Potential physiological significance and medicinal/industrial applications of the N-acylhomoserine lactone-degrading activity of acylase are discussed.

Ethanol-response genes and their regulation analyzed by a microarray and comparative genomic approach in the nematode Caenorhabditis elegans.

The nematode shows responses to acute ethanol exposure that are similar to those observed in humans, mice, and Drosophila, namely hyperactivity followed by uncoordination and sedation. We used in this report the nematode Caenorhabditis elegans as a model system to identify and characterize the genes that are affected by ethanol exposure and to link those genes functionally into an ethanol-induced gene network. By analyzing the expression profiles of all C. elegans ORFs using microarrays, we identified 230 genes affected by ethanol. While the ethanol response of some of the identified genes was significant at early time points, that of the majority was at late time points, indicating that the genes in the latter case might represent the physiological consequence of the ethanol exposure. We further characterized the early response genes that may represent those involved directly in the ethanol response. These genes included many heat shock protein genes, indicating that high concentration of ethanol acts as a strong stress to the animal. Interestingly, we identified two non-heat-shock protein genes that were specifically responsive to ethanol. glr-2 was the only glutamate receptor gene to be induced by ethanol. T28C12.4, which encodes a protein with limited homology to human neuroligin, was also specific to ethanol stress. Finally, by analyzing the promoter regions of the early response genes, we identified a regulatory element, TCTGCGTCTCT, that was necessary for the expression of subsets of ethanol response genes.

A global analysis of Caenorhabditis elegans operons.

The nematode worm Caenorhabditis elegans and its relatives are unique among animals in having operons. Operons are regulated multigene transcription units, in which polycistronic pre-messenger RNA (pre-mRNA coding for multiple peptides) is processed to monocistronic mRNAs. This occurs by 3' end formation and trans-splicing using the specialized SL2 small nuclear ribonucleoprotein particle for downstream mRNAs. Previously, the correlation between downstream location in an operon and SL2 trans-splicing has been strong, but anecdotal. Although only 28 operons have been reported, the complete sequence of the C. elegans genome reveals numerous gene clusters. To determine how many of these clusters represent operons, we probed full-genome microarrays for SL2-containing mRNAs. We found significant enrichment for about 1,200 genes, including most of a group of several hundred genes represented by complementary DNAs that contain SL2 sequence. Analysis of their genomic arrangements indicates that >90% are downstream genes, falling in 790 distinct operons. Our evidence indicates that the genome contains at least 1,000 operons, 2 8 genes long, that contain about 15% of all C. elegans genes. Numerous examples of co-transcription of genes encoding functionally related proteins are evident. Inspection of the operon list should reveal previously unknown functional relationships.