Indices of comparative cognition:Assessing animal models of human brain function

Understanding the cognitive capacities of animals is important, because (a) several animal models of human neurodegenerative disease are considered poor representatives of the human equivalent and (b) cognitive capacities may provide insight into alternative animal models. We used a three-stage process of cognitive and neuroanatomical comparison (using sheep as an example) to assess the appropriateness of a species to model human brain function. First, a cognitive task was defined via a reinforcement-learning algorithm where values/constants in the algorithm were taken as indirect measures of neurophysiological attributes. Second, cognitive data (values/constants) were generated for the example species (sheep) and compared to other species. Third, cognitive data were compared with neuroanatomical metrics for each species (endocranial volume, gyrification index, encephalisation quotient, and number of cortical neurons). Four breeds of sheep (n = 15/sheep) were tested using the two-choice discrimination-reversal task. The 'reversal index' was used as a measure of constants within the learning algorithm. Reversal index data ranked sheep as third in a table of species that included primates, dogs, and pigs. Across all species, number of cortical neurons correlated strongest against the reversal index (r2 = 0.66, p = 0.0075) followed by encephalization quotient (r2 = 0.42, p = 0.03), endocranial volume (r2 = 0.30, p = 0.08), and gyrification index (r2 = 0.16, p = 0.23). Sheep have a high predicted level of cognitive capacity and are thus a valid alternative model for neurodegenerative research. Using learning algorithms within cognitive tasks increases the resolution of methods of comparative cognition and can help to identify the most relevant species to model human brain function and dysfunction.CHDI In

A stop-signal task for sheep:Introduction and validation of a direct measure for the stop-signal reaction time

Huntington?s disease (HD) patients show reduced flexibility in inhibiting an already-started response. This can be quantified by the stop-signal task. The aim of this study was to develop and validate a sheep version of the stop-signal task that would be suitable for monitoring the progression of cognitive decline in a transgenic sheep model of HD. Using a semi-automated operant system, sheep were trained to perform in a two-choice discrimination task. In 22% of the trials, a stop-signal was presented. Upon the stop-signal presentation, the sheep had to inhibit their already-started response. The stopping behaviour was captured using an accelerometer mounted on the back of the sheep. This set-up provided a direct read-out of the individual stop-signal reaction time (SSRT). We also estimated the SSRT using the conventional approach of subtracting the stop-signal delay (i.e., time after which the stop-signal is presented) from the ranked reaction time during a trial without a stop-signal. We found that all sheep could inhibit an already-started response in 91% of the stop-trials. The directly measured SSRT (0.974 ? 0.04 s) was not significantly different from the estimated SSRT (0.938 ? 0.04 s). The sheep version of the stop-signal task adds to the repertoire of tests suitable for investigating both cognitive dysfunction and efficacy of therapeutic agents in sheep models of neurodegenerative disease such as HD, as well as neurological conditions such as attention deficit hyperactivity disorder.publishersversionPeer reviewe

A Convergent Synthetic Platform for Single-Nanoparticle Combination Cancer Therapy: Ratiometric Loading and Controlled Release of Cisplatin, Doxorubicin, and Camptothecin

The synthesis of polymer therapeutics capable of controlled loading and synchronized release of multiple therapeutic agents remains a formidable challenge in drug delivery and synthetic polymer chemistry. Herein, we report the synthesis of polymer nanoparticles (NPs) that carry precise molar ratios of doxorubicin, camptothecin, and cisplatin. To our knowledge, this work provides the first example of orthogonally triggered release of three drugs from single NPs. The highly convergent synthetic approach opens the door to new NP-based combination therapies for cancer.MIT Research Support CommitteeLincoln Laboratory. Advanced Concepts CommitteeUnited States. Dept. of Defense (Ovarian Cancer Research Program Teal Innovator Award)National Institutes of Health (U.S.) (Ruth L. Kirschstein National Research Service Award 1F32EB017614-01)Natural Sciences and Engineering Research Council of Canada (Postdoctoral Fellowship)Natural Sciences and Engineering Research Council of Canada (Graduate Fellowship)National Cancer Institute (U.S.) (Koch Institute Support (Core) Grant P30-CA14051

Personalizing neoadjuvant chemotherapy for locally advanced colon cancer:protocols for the international phase III FOxTROT2 and FOxTROT3 randomized controlled trials

AIM: FOxTROT1 established a new standard of care for managing locally advanced colon cancer (CC) with neoadjuvant chemotherapy (NAC). Six weeks of neoadjuvant oxaliplatin and fluoropyrimidine (OxFp) chemotherapy was associated with greater 2-year disease-free survival (DFS) when compared with proceeding straight to surgery (STS). There is now a need to refine the use of NAC and identify those most likely to benefit. FOxTROT2 will aim to investigate NAC in older adults and those with frailty. FOxTROT3 will aim to assess whether intensified triplet NAC provides additional benefits over OxFp.METHOD: FOxTROT2 and FOxTROT3 are international, open-label, phase III randomized controlled trials. Eligible patients will be identified by the multidisciplinary team. Patient age, frailty and comorbidities will be considered to guide trial entry. Participants will be randomized 2:1 to the intervention or control arm: 6 weeks of dose-adapted neoadjuvant OxFp versus STS in FOxTROT2 and 6 weeks of neoadjuvant modified oxaliplatin, 5-fluorouracil and irinotecan versus OxFp in FOxTROT3. The primary endpoint in FOxTROT2 is 3-year DFS. In FOxTROT3, tumour regression grade and 3-year DFS are co-primary endpoints.DISCUSSION: FOxTROT2 and FOxTROT3 will establish the FOxTROT platform, a key part of our long-term strategy to develop neoadjuvant treatments for CC. FOxTROT2 will investigate NAC in a population under-represented in FOxTROT1 and wider research. FOxTROT3 will assess whether it is possible to induce greater early tumour responses and whether this translates to superior long-term outcomes. Looking ahead, the FOxTROT platform will facilitate further trial comparisons and extensive translational research to optimize the use of NAC in CC.</p

A homozygous variant disrupting the PIGH start-codon is associated with developmental delay, epilepsy, and microcephaly.

Defective glycosylphosphatidylinositol (GPI)-anchor biogenesis can cause a spectrum of predominantly neurological problems. For eight genes critical to this biological process, disease associations are not yet reported. Scanning exomes from 7,833 parent-child trios and 1,792 singletons from the DDD study for biallelic variants in this gene-set uncovered a rare PIGH variant in a boy with epilepsy, microcephaly, and behavioral difficulties. Although only 2/2 reads harbored this c.1A > T transversion, the presence of ∼25 Mb autozygosity at this locus implied homozygosity, which was confirmed using Sanger sequencing. A similarly-affected sister was also homozygous. FACS analysis of PIGH-deficient CHO cells indicated that cDNAs with c.1A > T could not efficiently restore expression of GPI-APs. Truncation of PIGH protein was consistent with the utilization of an in-frame start-site at codon 63. In summary, we describe siblings harboring a homozygous c.1A > T variant resulting in defective GPI-anchor biogenesis and highlight the importance of exploring low-coverage variants within autozygous regions

Measuring Five Dimensions of Religiosity Across Adolescence

This paper theorizes and tests a latent variable model of adolescent religiosity in which five dimensions of religiosity are interrelated: religious beliefs, religious exclusivity, external religiosity, private practice, and religious salience. Research often theorizes overlapping and independent influences of single items or dimensions of religiosity on outcomes such as adolescent sexual behavior, but rarely operationalizes the dimensions in a measurement model accounting for their associations with each other and across time. We use longitudinal structural equation modeling (SEM) with latent variables to analyze data from two waves of the National Study of Youth and Religion. We test our hypothesized measurement model as compared to four alternate measurement models and find that our proposed model maintains superior fit. We then discuss the associations between the five dimensions of religiosity we measure and how these change over time. Our findings suggest how future research might better operationalize multiple dimensions of religiosity in studies of the influence of religion in adolescence

Diagnostic value of exome and whole genome sequencing in craniosynostosis

Background Craniosynostosis, the premature fusion of one or more cranial sutures, occurs in ~1 in 2250 births, either in isolation or as part of a syndrome. Mutations in at least 57 genes have been associated with craniosynostosis, but only a minority of these are included in routine laboratory genetic testing. Methods We used exome or whole genome sequencing to seek a genetic cause in a cohort of 40 subjects with craniosynostosis, selected by clinical or molecular geneticists as being high-priority cases, and in whom prior clinically driven genetic testing had been negative. Results We identified likely associated mutations in 15 patients (37.5%), involving 14 different genes. All genes were mutated in single families, except for IL11RA (two families). We classified the other positive diagnoses as follows: commonly mutated craniosynostosis genes with atypical presentation (EFNB1, TWIST1); other core craniosynostosis genes (CDC45, MSX2, ZIC1); genes for which mutations are only rarely associated with craniosynostosis (FBN1, HUWE1, KRAS, STAT3); and known disease genes for which a causal relationship with craniosynostosis is currently unknown (AHDC1, NTRK2). In two further families, likely novel disease genes are currently undergoing functional validation. In 5 of the 15 positive cases, the (previously unanticipated) molecular diagnosis had immediate, actionable consequences for either genetic or medical management (mutations in EFNB1, FBN1, KRAS, NTRK2, STAT3). Conclusions This substantial genetic heterogeneity, and the multiple actionable mutations identified, emphasises the benefits of exome/whole genome sequencing to identify causal mutations in craniosynostosis cases for which routine clinical testing has yielded negative results

The Importance of Eurekan Mountains on Cenozoic Sediment Routing on the Western Barents Shelf

The importance of topography generated by Eocene Eurekan deformation as a sediment source for sandstones deposited on the western Barents Shelf margin is evaluated through a sediment provenance study conducted on wellbore materials retrieved from Spitsbergen and from the Vestbakken Volcanic Province and the Sørvestsnaget Basin in the southwest Barents Sea. A variety of complementary techniques record a provenance change across the Paleocene-Eocene boundary in wellbore BH 10-2008, which samples Paleogene strata of the Central Tertiary Basin in Spitsbergen. Sandstones containing K-feldspar with radiogenic Pb isotopic compositions, chrome spinel in the heavy mineral assemblage, and detrital zircons and rutiles with prominent Palaeoproterozoic and Late Palaeozoic—Early Mesozoic U-Pb age populations are up-section replaced by sandstone containing albitic plagioclase feldspar, metasedimentary schist rock fragments, a heavy mineral assemblage with abundant chloritoid, metamorphic apatite with low REE contents, metapelitic rutile with Silurian U-Pb ages and zircons with predominantly Archaean and Palaeoproterozoic U-Pb age populations. Our results clearly demonstrate the well-known regional change in source area from an exposed Barents Shelf terrain east of the Central Tertiary Basin during the Paleocene to the emerging Eurekan mountains west and north of the Central Tertiary Basin during the Eocene. Eocene sandstones deposited in the marginal basins of the southwestern Barents Shelf, which were sampled in wellbores 7316/5-1 and 7216/11-1S, contain elements of both the Eurekan and the eastern Barents Shelf provenance signatures. The mixing of the two sand types and delivery to the southwest margin of the Barents Shelf is consistent with a fill and spill model for the Central Teritary Basin, with transport of Eurekan-derived sediment east then south hundreds of kilometres across the Shelf