A Cost-Effective Microfluidic Device to Teach the Principles of Electrophoresis and Electroosmosis

Electrophoresis is integral to analytical and biochemistry experiences in undergraduate education; however, fundamental principles of the method are often taught in upper-level laboratories through hands-on experiences. A laboratory activity is reported that teaches the concepts of electrophoretic mobility and electroosmotic flow. A single reuseable instrument, called a mini-E, costs 37 USD and consists of a DC power supply, a voltmeter, platinum electrodes, and a chip cast in polydimethylsiloxane. This activity uses common reagents costing only 0.02 USD per student. Experiments are devised that allow students to investigate the properties of electrophoretic flow and electroosmotic flow by separating the two commonly used food dyeing agents Brilliant Blue FCF and Allura Red AC in vinegar and in a solution of ammonium hydroxide. A dark-purple mixture of these dyes is separated into red and blue bands that are easily visualized. The migration order of the dyes differs when the separation is performed under conditions of reversed polarity and suppressed electroosmotic flow (vinegar) compared to conditions of normal polarity and active electroosmotic flow (ammonium hydroxide). When delivered to chemistry majors, students had a significant gain in their ability to apply the concepts of electroosmosis and electrophoresis to predict analyte migration. Although this activity targets upper-level chemistry content, it can also be adapted for other laboratory experiences.

Preclinical studies of a PARP targeted, Meitner-Auger emitting, theranostic radiopharmaceutical for metastatic ovarian cancer

Advanced ovarian cancer currently has few therapeutic options. Poly(ADP-ribose) polymerase (PARP) inhibitors bind to nuclear PARP and trap the protein-inhibitor complex to DNA. This work investigates a theranostic PARP inhibitor for targeted radiopharmaceutical therapy of ovarian cancer in vitro and PET imaging of healthy mice in vivo.

METHODS

[77Br]RD1 was synthesized and assessed for pharmacokinetics and cytotoxicity in human and murine ovarian cancer cell lines. [76Br]RD1 biodistribution and organ uptake in healthy mice were quantified through longitudinal PET/CT imaging and ex vivo radioactivity measurements. Organ-level dosimetry following [76/77Br]RD1 administration was calculated using RAPID, an in-house platform for absorbed dose in mice, and OLINDA for equivalent and effective dose in human.

RESULTS

The maximum specific binding (Bmax), equilibrium dissociation constant (Kd), and nonspecific binding slope (NS) were calculated for each cell line. These values were used to calculate the cell specific activity uptake for cell viability studies. The half maximal effective concentration (EC50) was measured as 0.17 (95 % CI: 0.13-0.24) nM and 0.46 (0.13-0.24) nM for PARP(+) and PARP(-) expressing cell lines, respectively. The EC50 was 0.27 (0.21-0.36) nM and 0.30 (0.22-0.41) nM for BRCA1(-) and BRCA1(+) expressing cell lines, respectively. When measuring the EC50 as a function of cellular activity uptake and nuclear dose, the EC50 ranges from 0.020 to 0.039 Bq/cell and 3.3-9.2 Gy, respectively. Excretion through the hepatobiliary and renal pathways were observed in mice, with liver uptake of 2.3 ± 0.4 %ID/g after 48 h, contributing to estimated absorbed dose values in mice of 19.3 ± 0.3 mGy/MBq and 290 ± 10 mGy/MBq for [77Br]RD1 and [76Br]RD1, respectively.

CONCLUSION

[77Br]RD1 cytotoxicity was dependent on PARP expression and independent of BRCA1 status. The in vitro results suggest that [77Br]RD1 cytotoxicity is driven by the targeted Meitner-Auger electron (MAe) radiotherapeutic effect of the agent. Further studies investigating the theranostic potential, organ dose, and tumor uptake of [76/77Br]RD1 are warranted.

A note on the use of rank-ordered logit models for ordered response categories

Models for rankings have been shown to produce more efficient estimators than comparable models for first/top choices. The discussions and applications of these models typically only consider unordered alternatives. But these models can be usefully adapted to the case where a respondent ranks a set of ordered alternatives that are ordered response categories. This paper proposes eliciting a rank order that is consistent with the ordering of the response categories, and then modelling the observed rankings using a variant of the rank ordered logit model where the distribution of rankings has been truncated to the set of admissible rankings. This results in lower standard errors in comparison to when only a single top category is selected by the respondents. And the restrictions on the set of admissible rankings reduces the number of decisions needed to be made by respondents in comparison to ranking a set of unordered alternatives. Simulation studies and application examples featuring models based on a stereotype regression model and a rating scale item response model are provided to demonstrate the utility of this approach.

Vegetation and vantage point influence visibility across diverse ecosystems: Implications for animal ecology

Visual information can influence animal behavior and habitat use in diverse ways. Visibility is the property that relates 3D habitat structure to accessibility of visual information. Despite the importance of visibility in animal ecology, this property remains largely unstudied. Our objective was to assess how habitat structure from diverse environments and animal position within that structure can influence visibility. We gathered terrestrial lidar data (1 cm at 10 m) in four ecosystems (forest, shrub-steppe, prairie, and desert) to characterize viewsheds (i.e., estimates of visibility based on spatially explicit sightlines) from multiple vantage points. Both ecosystem-specific structure and animal position influenced potential viewsheds. Generally, as height of the vantage point above the ground increased, viewshed extent also increased, but the relationships were not linear. In low-structure ecosystems (prairie, shrub-steppe, and desert), variability in viewsheds decreased as vantage points increased to heights above the vegetation canopy. In the forest, however, variation in viewsheds was highest at intermediate heights, and markedly lower at the lowest and highest vantage points. These patterns are likely linked to the amount, heterogeneity, and distribution of vegetation structure occluding sightlines. Our work is the first to apply a new method that can be used to estimate viewshed properties relevant to animals (i.e., viewshed extent and variability). We demonstrate that these properties differ across terrestrial landscapes in complex ways that likely influence many facets of animal ecology and behavior.

An investigation of kV mini-GRID spatially fractionated radiation therapy: dosimetry and preclinical trial

Objective. To develop and characterize novel methods of extreme spatially fractionated kV radiation therapy (including mini-GRID therapy) and to evaluate efficacy in the context of a pre-clinical mouse study.Approach. Spatially fractionated GRIDs were precision-milled from 3 mm thick lead sheets compatible with mounting on a 225 kVp small animal irradiator (X-Rad). Three pencil-beam GRIDs created arrays of 1 mm diameter beams, and three 'bar' GRIDs created 1 × 20 mm rectangular fields. GRIDs projected 20 × 20 mm²fields at isocenter, and beamlets were spaced at 1, 1.25, and 1.5 mm, respectively. Peak-to-valley ratios and dose distributions were evaluated with Gafchromic film. Syngeneic transplant tumors were induced by intramuscular injection of a soft tissue sarcoma cell line into the gastrocnemius muscle of C57BL/6 mice. Tumor-bearing mice were randomized to four groups: unirradiated control, conventional irradiation of entire tumor, GRID therapy, and hemi-irradiation (half-beam block, 50% tumor volume treated). All irradiated mice received a single fraction of 15 Gy.Results. High peak-to-valley ratios were achieved (bar GRIDs: 11.9 ± 0.9, 13.6 ± 0.4, 13.8 ± 0.5; pencil-beam GRIDs: 18.7 ± 0.6, 26.3 ± 1.5, 31.0 ± 3.3). Pencil-beam GRIDs could theoretically spare more intra-tumor immune cells than bar GRIDs, but they treat less tumor tissue (3%-4% versus 19%-23% area receiving 90% prescription, respectively). Bar GRID and hemi-irradiation treatments significantly delayed tumor growth (P < 0.05), but not as much as a conventional treatment (P < 0.001). No significant difference was found in tumor growth delay between GRID and hemi-irradiation.Significance. High peak-to-valley ratios were achieved with kV grids: two-to-five times higher than values reported in literature for MV grids. GRID irradiation and hemi-irradiation delayed tumor growth, but neither was as effective as conventional whole tumor uniform dose treatment. Single fraction GRID therapy could not initiate an anti-cancer immune response strong enough to match conventional RT outcomes, but follow-up studies will evaluate the combination of mini-GRID with immune checkpoint blockade.

Estimation of the strength of mate preference from mated pairs observed in the wild

A number of key processes in evolution are driven by individuals preferring mates with particular phenotypes. However, despite long‐standing interest, it is difficult to quantify the strength of mate preference from phenotypic observations in nature in a way that connects directly to key parameters in theoretical models. To bridge the gap between mathematical models and empirical data, we develop a novel maximum likelihood‐based method to estimate the strength and form of mate preference, where preference depends on traits expressed in both males and females. Using simulated data, we demonstrate that our method accurately infers model parameters, including the strength of mate preference and the optimal offset match between trait values in mated pairs when model assumptions are satisfied. Applying our method to two previous studies of assortative mating in marine gastropods and the European common frog, we support previous findings, but also give additional insight into the role of mate preference in each system. Our method can be generalized to a variety of plant and animal taxa that exhibit mating preferences to facilitate the testing of evolutionary hypotheses and link empirical data to theoretical models of assortative mating, sexual selection, and speciation.

Linking forest management to moose population trends: The role of the nutritional landscape

Forested lands in the western USA have undergone changes in management and condition that are resulting in a shift towards climax vegetation. These changes can influence the quality and quantity of forage for herbivores that rely on early-seral plants. To evaluate how management of forested landscapes might affect nutrition for Shiras moose (A. a. shirasi) at large spatial scales, we focused on shrubs and evaluated summer diet composition, forage availability, and forage quality across 21 population management units encompassing >36,000 km² in northern Idaho, USA. We identified 17 shrub species in the diets of moose, 11 of which comprised the bulk of the diets. These forage shrubs varied markedly in both energy (mean digestible energy for leaves ranged from 9.62 to 12.89 kJ/g) and protein (mean digestible protein for leaves ranged from 1.73 to 7.90%). By adapting established field sampling methods and integrating recent advances in remote sensing analyses in a modeling framework, we predicted approximations of current and past (i.e., 1984) quantities of forage shrubs across northern Idaho. We also created a qualitative index of population trend for moose across population management units using harvest data. Predicted quantities of forage shrubs varied widely across the study area with generally higher values at more northern latitudes. The quantity of forage shrubs was estimated to have declined over the past 30 years in about half of the population management units, with the greatest declines predicted for high-energy forage species. The population trend index was correlated with the percent change in availability of moderate-energy forage shrubs, indicating that availability of forage shrubs and change in availability over time might be affecting population dynamics for moose in northern Idaho. Our study highlights the importance of assessing how changes in forest management across broad spatiotemporal extents could affect wildlife and their habitats.

Seasonal temperature acclimatization in a semi-fossorial mammal and the role of burrows as thermal refuges

Small mammals in habitats with strong seasonal variation in the thermal environment often exhibit physiological and behavioral adaptations for coping with thermal extremes and reducing thermoregulatory costs. Burrows are especially important for providing thermal refuge when above-ground temperatures require high regulatory costs (e.g., water or energy) or exceed the physiological tolerances of an organism. Our objective was to explore the role of burrows as thermal refuges for a small endotherm, the pygmy rabbit (Brachylagus idahoensis), during the summer and winter by quantifying energetic costs associated with resting above and below ground. We used indirect calorimetry to determine the relationship between energy expenditure and ambient temperature over a range of temperatures that pygmy rabbits experience in their natural habitat. We also measured the temperature of above- and below-ground rest sites used by pygmy rabbits in eastern Idaho, USA, during summer and winter and estimated the seasonal thermoregulatory costs of resting in the two microsites. Although pygmy rabbits demonstrated seasonal physiological acclimatization, the burrow was an important thermal refuge, especially in winter. Thermoregulatory costs were lower inside the burrow than in above-ground rest sites for more than 50% of the winter season. In contrast, thermal heterogeneity provided by above-ground rest sites during summer reduced the role of burrows as a thermal refuge during all but the hottest periods of the afternoon. Our findings contribute to an understanding of the ecology of small mammals in seasonal environments and demonstrate the importance of burrows as thermal refuge for pygmy rabbits.

The balancing act of foraging: mammalian herbivores trade-off multiple risks when selecting food patches

Animals face multiple risks while foraging such as the risk of acquiring inadequate energy from food and the risk of predation. We evaluated how two sympatric rabbits (pygmy rabbits, Brachylagus idahoensis, and mountain cottontail rabbits, Sylvilagus nuttallii) that differ in size, use of burrows, and habitat specialization in the sagebrush-steppe of western North America respond to different types and levels of perceived risks (i.e., fitness cost × probability of occurrence), including fiber and toxins in food, exposure to predation, and distance from a refuge. We measured food intake by the rabbits at paired food patches that varied in these risks and used the method of paired comparisons to create a relative ranking of habitat cues, which revealed an animal's perceived risk on a single scale representing an integrated response to a variety of risks. Pygmy rabbits perceived exposure to predation risk and distance from a burrow as riskier than did cottontails, whereas cottontails perceived dietary toxin as riskier. Pygmy rabbits consumed lower quality food, containing higher fiber or toxins, thereby avoided feeding in exposed patches or traveling far from their burrow to forage. In contrast, cottontails fed in exposed patches and traveled farther from the burrow to obtain higher quality food. We have shown how risks can be integrated into a single model that allows animals to reveal their perceptions of risks on a single scale that can be used to create a spatially explicit landscape of risk.

Evaluation of micro-GPS receivers for tracking small-bodied mammals

GPS telemetry markedly enhances the temporal and spatial resolution of animal location data, and recent advances in micro-GPS receivers permit their deployment on small mammals. One such technological advance, snapshot technology, allows for improved battery life by reducing the time to first fix via postponing recovery of satellite ephemeris (satellite location) data and processing of locations. However, no previous work has employed snapshot technology for small, terrestrial mammals. We evaluated performance of two types of micro-GPS (< 20 g) receivers (traditional and snapshot) on a small, semi-fossorial lagomorph, the pygmy rabbit (Brachylagus idahoensis), to understand how GPS errors might influence fine-scale assessments of space use and habitat selection. During stationary tests, microtopography (i.e., burrows) and satellite geometry had the largest influence on GPS fix success rate (FSR) and location error (LE). There was no difference between FSR while animals wore the GPS collars above ground (determined via light sensors) and FSR generated during stationary, above-ground trials, suggesting that animal behavior other than burrowing did not markedly influence micro-GPS errors. In our study, traditional micro-GPS receivers demonstrated similar FSR and LE to snapshot receivers, however, snapshot receivers operated inconsistently due to battery and software failures. In contrast, the initial traditional receivers deployed on animals experienced some breakages, but a modified collar design consistently functioned as expected. If such problems were resolved, snapshot technology could reduce the tradeoff between fix interval and battery life that occurs with traditional micro-GPS receivers. Our results suggest that micro-GPS receivers are capable of addressing questions about space use and resource selection by small mammals, but that additional techniques might be needed to identify use of habitat structures (e.g., burrows, tree cavities, rock crevices) that could affect micro-GPS performance and bias study results.

Evaluation of micro-GPS receivers for tracking small-bodied mammals

GPS telemetry markedly enhances the temporal and spatial resolution of animal location data, and recent advances in micro-GPS receivers permit their deployment on small mammals. One such technological advance, snapshot technology, allows for improved battery life by reducing the time to first fix via postponing recovery of satellite ephemeris (satellite location) data and processing of locations. However, no previous work has employed snapshot technology for small, terrestrial mammals. We evaluated performance of two types of micro-GPS (< 20 g) receivers (traditional and snapshot) on a small, semi-fossorial lagomorph, the pygmy rabbit (Brachylagus idahoensis), to understand how GPS errors might influence fine-scale assessments of space use and habitat selection. During stationary tests, microtopography (i.e., burrows) and satellite geometry had the largest influence on GPS fix success rate (FSR) and location error (LE). There was no difference between FSR while animals wore the GPS collars above ground (determined via light sensors) and FSR generated during stationary, above-ground trials, suggesting that animal behavior other than burrowing did not markedly influence micro-GPS errors. In our study, traditional micro-GPS receivers demonstrated similar FSR and LE to snapshot receivers, however, snapshot receivers operated inconsistently due to battery and software failures. In contrast, the initial traditional receivers deployed on animals experienced some breakages, but a modified collar design consistently functioned as expected. If such problems were resolved, snapshot technology could reduce the tradeoff between fix interval and battery life that occurs with traditional micro-GPS receivers. Our results suggest that micro-GPS receivers are capable of addressing questions about space use and resource selection by small mammals, but that additional techniques might be needed to identify use of habitat structures (e.g., burrows, tree cavities, rock crevices) that could affect micro-GPS performance and bias study results.

A randomized clinical trial of a culturally responsive intervention for African American women with asthma

BACKGROUND

Few interventions have focused on the difficulties that African American women face when managing asthma.

OBJECTIVE

To evaluate a telephone-based self-regulation intervention that emphasized African American women's management of asthma in a series of 6 sessions.

METHODS

A total of 422 African American women with persistent asthma were randomly assigned to either an intervention or control group receiving usual care. Behavioral factors, symptoms and asthma control, asthma-related quality of life, and health care use at baseline and 2 years after baseline were assessed. Generalized estimating equations were used to assess the long-term effect of the intervention on outcomes.

RESULTS

Compared with the control group, those who completed the full intervention (6 sessions) had significant gains in self-regulation of their asthma (B estimate, 0.73; 95% CI, 0.17-1.30; P < .01), noticing changes to their asthma during their menstrual cycle (B estimate, 1.42; 95% CI, 0.69-2.15; P < .001), and when having premenstrual syndrome (B estimate, 1.70; 95% CI, 0.67-2.72; P < .001). They also had significant reductions in daytime symptoms (B estimate, -0.15; 95% CI, -0.27 to -0.03; P < .01), asthma-related hospitalization (B estimate, 0.51; 95% CI, 0.00-1.02; P < .05), and improved asthma control (B estimate, 1.34; 95% CI, 0.57-2.12; P < .001). However, neither grouped changed over time in outcomes.

CONCLUSION

Despite high comorbidity, African American women who completed a culturally responsive self-management program had improvements in asthma outcomes compared with the control group. Future work should address significant comorbidities and psychosocial issues alongside asthma management to improve asthma outcomes in the long term.

TRIAL REGISTRATION

clinicaltrials.gov Identifier NCT01117805.

Selection of food patches by sympatric herbivores in response to concealment and distance from a refuge

Small herbivores face risks of predation while foraging and are often forced to trade off food quality for safety. Life history, behaviour, and habitat of predator and prey can influence these trade-offs. We compared how two sympatric rabbits (pygmy rabbit, Brachylagus idahoensis; mountain cottontail, Sylvilagus nuttallii) that differ in size, use of burrows, and habitat specialization in the sagebrush-steppe of western North America respond to amount and orientation of concealment cover and proximity to burrow refuges when selecting food patches. We predicted that both rabbit species would prefer food patches that offered greater concealment and food patches that were closer to burrow refuges. However, because pygmy rabbits are small, obligate burrowers that are restricted to sagebrush habitats, we predicted that they would show stronger preferences for greater cover, orientation of concealment, and patches closer to burrow refuges. We offered two food patches to individuals of each species during three experiments that either varied in the amount of concealment cover, orientation of concealment cover, or distance from a burrow refuge. Both species preferred food patches that offered greater concealment, but pygmy rabbits generally preferred terrestrial and mountain cottontails preferred aerial concealment. Only pygmy rabbits preferred food patches closer to their burrow refuge. Different responses to concealment and proximity to burrow refuges by the two species likely reflect differences in perceived predation risks. Because terrestrial predators are able to dig for prey in burrows, animals like pygmy rabbits that rely on burrow refuges might select food patches based more on terrestrial concealment. In contrast, larger habitat generalists that do not rely on burrow refuges, like mountain cottontails, might trade off terrestrial concealment for visibility to detect approaching terrestrial predators. This study suggests that body size and evolutionary adaptations for using habitat, even in closely related species, might influence anti-predator behaviors in prey species.

Consequences for conservation: population density and genetic effects on reproduction of an endangered lagomorph

Understanding reproduction and mating systems is important for managers tasked with conserving vulnerable species. Genetic tools allow biologists to investigate reproduction and mating systems with high resolution and are particularly useful for species that are otherwise difficult to study in their natural environments. We conducted parentage analyses using 19 nuclear DNA microsatellite loci to assess the influence of population density, genetic diversity, and ancestry on reproduction, and to examine the mating system of pygmy rabbits (Brachylagus idahoensis) bred in large naturalized enclosures for the reintroduction and recovery of the endangered distinct population in central Washington, USA. Reproductive output for females and males decreased as population density and individual homozygosity increased. We identified an interaction indicating that male reproductive output decreased as genetic diversity declined at high population densities, but there was no effect at low densities. Males with high amounts (> 50%) of Washington ancestry had higher reproductive output than the other ancestry groups, while reproductive output was decreased for males with high northern Utah/Wyoming ancestry and females with high Oregon/Nevada ancestry. Females and males bred with an average of 3.8 and 3.6 mates per year, respectively, and we found no evidence of positive or negative assortative mating with regards to ancestry. Multiple paternity was confirmed in 81% of litters, and we report the first documented cases of juvenile breeding by pygmy rabbits. This study demonstrates how variation in population density, genetic diversity, and ancestry impact fitness for an endangered species being bred for conservation. Our results advance understanding of basic life history characteristics for a cryptic species that is difficult to study in the wild and provide lessons for managing populations of vulnerable species in captive and free-ranging populations.

Modeling trade-offs between plant fiber and toxins: a framework for quantifying risks perceived by foraging herbivores

When selecting habitats, herbivores must weigh multiple risks, such as predation, starvation, toxicity, and thermal stress, forcing them to make fitness trade-offs. Here, we applied the method of paired comparisons (PC) to investigate how herbivores make trade-offs between habitat features that influence selection of food patches. The method of PC measures utility and the inverse of utility, relative risk, and makes trade-offs and indifferences explicit by forcing animals to make choices between two patches with different types of risks. Using a series of paired-choice experiments to titrate the equivalence curve and find the marginal rate of substitution for one risk over the other, we evaluated how toxin-tolerant (pygmy rabbit Brachylagus idahoensis) and fiber-tolerant (mountain cottontail rabbit Sylviagus nuttallii) herbivores differed in their hypothesized perceived risk of fiber and toxins in food. Pygmy rabbits were willing to consume nearly five times more of the toxin 1,8-cineole in their diets to avoid consuming higher levels of fiber than were mountain cottontails. Fiber posed a greater relative risk for pygmy rabbits than cottontails and cineole a greater risk for cottontails than pygmy rabbits. Our flexible modeling approach can be used to (1) quantify how animals evaluate and trade off multiple habitat attributes when the benefits and risks are difficult to quantify, and (2) integrate diverse risks that influence fitness and habitat selection into a single index of habitat value. This index potentially could be applied to landscapes to predict habitat selection across several scales.

The role of wood hardness in limiting nest site selection in avian cavity excavators

Woodpeckers and other primary cavity excavators (PCEs) are important worldwide for excavating cavities in trees, and a large number of studies have examined their nesting preferences. However, quantitative measures of wood hardness have been omitted from most studies, and ecologists have focused on the effects of external tree- and habitat-level features on nesting. Moreover, information is lacking on the role of wood hardness in limiting nesting opportunities for this important guild. Here, we used an information theoretic approach to examine the role of wood hardness in multi-scale nest site selection and in limiting nesting opportunities for six species of North American PCEs. We found that interior wood hardness at nests (n = 259) differed from that at random sites, and all six species of PCE had nests with significantly softer interior wood than random trees (F1,517 = 106.15, P < 0.0001). Accordingly, interior wood hardness was the most influential factor in our models of nest site selection at both spatial scales that we examined: in the selection of trees within territories and in the selection of nest locations on trees. Moreover, regardless of hypothesized excavation abilities, all the species in our study appeared constrained by interior wood hardness, and only 4-14% of random sites were actually suitable for nesting. Our findings suggest that past studies that did not measure wood hardness counted many sites as available to PCEs when they were actually unsuitable, potentially biasing results. Moreover, by not accounting for nest site limitations in PCEs, managers may overestimate the amount of suitable habitat. We therefore urge ecologists to incorporate quantitative measures of wood hardness into PCE nest site selection studies, and to consider the limitations faced by avian cavity excavators in forest management decisions.

Balancing sample accumulation and DNA degradation rates to optimize noninvasive genetic sampling of sympatric carnivores

Noninvasive genetic sampling, or noninvasive DNA sampling (NDS), can be an effective monitoring approach for elusive, wide-ranging species at low densities. However, few studies have attempted to maximize sampling efficiency. We present a model for combining sample accumulation and DNA degradation to identify the most efficient (i.e. minimal cost per successful sample) NDS temporal design for capture-recapture analyses. We use scat accumulation and faecal DNA degradation rates for two sympatric carnivores, kit fox (Vulpes macrotis) and coyote (Canis latrans) across two seasons (summer and winter) in Utah, USA, to demonstrate implementation of this approach. We estimated scat accumulation rates by clearing and surveying transects for scats. We evaluated mitochondrial (mtDNA) and nuclear (nDNA) DNA amplification success for faecal DNA samples under natural field conditions for 20 fresh scats/species/season from <1-112 days. Mean accumulation rates were nearly three times greater for coyotes (0.076 scats/km/day) than foxes (0.029 scats/km/day) across seasons. Across species and seasons, mtDNA amplification success was ≥95% through day 21. Fox nDNA amplification success was ≥70% through day 21 across seasons. Coyote nDNA success was ≥70% through day 21 in winter, but declined to <50% by day 7 in summer. We identified a common temporal sampling frame of approximately 14 days that allowed species to be monitored simultaneously, further reducing time, survey effort and costs. Our results suggest that when conducting repeated surveys for capture-recapture analyses, overall cost-efficiency for NDS may be improved with a temporal design that balances field and laboratory costs along with deposition and degradation rates.

Grazing in sagebrush rangelands in western North America: implications for habitat quality for a sagebrush specialist, the pygmy rabbit

Livestock grazing is one of the primary uses of sagebrush rangelands in western North America; therefore, an understanding of the ecological implications of grazing on habitat quality for sagebrush-dependent wildlife is needed to help land managers balance multiple objectives for land use. We studied effects of cattle grazing on components of habitat for an uncommon sagebrush habitat specialist, the pygmy rabbit (Brachylagus idahoensis), which has been petitioned for endangered or threatened status in the USA. We evaluated multiple components of habitat before and after grazing in replicated control and treatment plots in a mesic, high-elevation sagebrush-steppe environment in south-western Montana, USA. We predicted that grazing would decrease the biomass of herbaceous forage, alter security cover, and increase rate of collapse of rabbit burrows, and we expected that these effects would be more pronounced during summer than spring. As expected, cattle grazing reduced the biomass of perennial grasses available to pygmy rabbits after grazing that occurred during either spring or summer, and the biomass of forbs after spring grazing. In contrast, grazing did not markedly influence the functional properties of vegetation related to predation risk or the integrity of rabbit burrow systems. In the context of the stocking rate of the allotments in our study (7.3 acres/Animal Unit Month, 2.95 ha/Animal Unit Month), annual cattle grazing did not seem to markedly change habitat for pygmy rabbits in our study area; however, longer-term and higher intensity grazing might result in more pronounced habitat changes. Understanding the ecological implications of cattle grazing on habitat quality for pygmy rabbits and other sagebrush-dependent wildlife can guide conservation strategies for these species on sagebrush rangelands managed under multiple-use policies.

Generalized linear models with coarsened covariates: a practical Bayesian approach

Coarsened covariates are a common and sometimes unavoidable phenomenon encountered in statistical modeling. Covariates are coarsened when their values or categories have been grouped. This may be done to protect privacy or to simplify data collection or analysis when researchers are not aware of their drawbacks. Analyses with coarsened covariates based on ad hoc methods can compromise the validity of inferences. One valid method for accounting for a coarsened covariate is to use a marginal likelihood derived by summing or integrating over the unknown realizations of the covariate. However, algorithms for estimation based on this approach can be tedious to program and can be computationally expensive. These are significant obstacles to their use in practice. To overcome these limitations, we show that when expressed as a Bayesian probability model, a generalized linear model with a coarsened covariate can be posed as a tractable missing data problem where the missing data are due to censoring. We also show that this model is amenable to widely available general-purpose software for simulation-based inference for Bayesian probability models, providing researchers a very practical approach for dealing with coarsened covariates.

Effects of genetic management on reproduction, growth, and survival in captive endangered pygmy rabbits (Brachylagus idahoensis)

A quarter of all lagomorph species worldwide are threatened with extinction. Captive breeding programs, such as that developed for the Columbia Basin (CB) pygmy rabbit (Brachylagus idahoensis), sometimes are implemented as emergency conservation measures to restore small, genetically distinct populations. However, small source populations also may have low genetic diversity, which may influence attributes related to fitness, including growth, survival, and reproduction. We used mixed-effects regression models to explore the influence of genetic pedigree (% CB) on pairing success, growth, and survival during the 10-year captive breeding program at Washington State University, which included controlled pairings and outbreeding with pygmy rabbits from Idaho. Pairing success, juvenile growth, and juvenile survival declined with increasing CB pedigree of 1 or both parents, suggesting inbreeding depression among the small number of related founders. Demographic variables such as age, sex, and previous pregnancies, and environmental variables such as month and temperature at birth also were associated with production of pygmy rabbits. Our study illustrates the difficulty of retaining a unique genome of a small source population while simultaneously producing enough rabbits for restoration into natural habitat as part of endangered species recovery programs.

Evaluating DNA degradation rates in faecal pellets of the endangered pygmy rabbit

Noninvasive genetic sampling of faecal pellets can be a valuable method for monitoring rare and cryptic wildlife populations, like the pygmy rabbit (Brachylagus idahoensis). To investigate this method's efficiency for pygmy rabbit monitoring, we evaluated the effect of sample age on DNA degradation in faecal pellets under summer field conditions. We placed 275 samples from known individuals in natural field conditions for 1-60 days and assessed DNA quality by amplifying a 294-base-pair (bp) mitochondrial DNA (mtDNA) locus and five nuclear DNA (nDNA) microsatellite loci (111-221 bp). DNA degradation was influenced by sample age, DNA type, locus length and rabbit sex. Both mtDNA and nDNA exhibited high PCR success rates (94.4%) in samples <1 day old. Success rates for microsatellite loci declined rapidly from 80.0% to 42.7% between days 5 and 7, likely due to increased environmental temperature. Success rates for mtDNA amplification remained higher than nDNA over time, with moderate success (66.7%) at 21 days. Allelic dropout rates were relatively high (17.6% at <1 day) and increased to 100% at 60 days. False allele rates ranged from 0 to 30.0% and increased gradually over time. We recommend collecting samples as fresh as possible for individual identification during summer field conditions. Our study suggests that this method can be useful for future monitoring efforts, including occupancy surveys, individual identification, population estimation, parentage analysis and monitoring of genetic diversity both of a re-introduced population in central Washington and across their range.

Outcomes associated with a negotiated asthma treatment plan

Negotiated treatment plans are increasingly recommended in asthma clinical care. However, limited data are available to indicate whether this more patient-engaged process results in improved health outcomes. The aim of this study was to determine the associations between the presence of a negotiated treatment plan and the outcomes related to adherence to the medical regimen, symptom control, and health care use. The focus of the study was on women, the subgroup of adult patients, who are most vulnerable for negative asthma outcomes. Data were collected by telephone interview and medical record review from 808 women diagnosed with asthma at baseline, first year, and second year follow-up. Associations were examined between the presence of a negotiated treatment plan at baseline and subsequent asthma outcomes. Women with a negotiated treatment plan reported more adherent to prescribed asthma medicines (odds ratio (OR) = 2.41, 95% confidence interval (CI) = (1.82, 3.19)) and those with a plan and using oral steroids at baseline had less oral steroid use at follow-up (OR = 0.21, 95% CI = (0.05, 0.93)). Women with a negotiated plan also had more days (17%, 95% CI = (8, 27)) and nights (31%, 95% CI = (16, 48)) with symptoms than those without such a plan. No differences in hospitalizations, emergency department visits, or urgent physician office visits were noted between the groups. Patients with higher education levels were more likely to have a negotiated treatment plan. Negotiated treatment plans appear to have achieved greater adherence to prescribed asthma medicines and less need for oral steroids but were not related to fewer symptoms of asthma or reductions in urgent health care use. Additional strategies may be needed to reduce symptom and health services utilization outcomes.

A COMPARISON OF TWO TIME INTERVALS FOR THE AUSCULTATED ACCELERATION TEST

OBJECTIVE

Interest in an inexpensive, easy-to-administer antenatal screening test that did not rely on the use of electronic fetal monitoring led to development of the fetoscope administered auscultated acceleration test (AAT) in the late 1980s. More recent efforts have been directed toward providing those who may use the AAT with important information about the most effective and clinically appropriate AAT procedures. The purpose of this study was to determine the screening test validity performance of two AAT time intervals--6 minutes and 10 minutes.

METHODS

Two auscultated acceleration tests (AAT6 and AAT10) were simultaneously performed using different time intervals on 205 women with high-risk pregnancies undergoing simultaneous nonstress tests (NSTS) who were referred to a tertiary care unit for antepartum testing. Standard measurements of screening test validity were calculated for each test in the prediction of selected perinatal outcomes. NST findings were included for comparative purposes.

RESULTS

The AAT6 yielded an overall higher specificity as compared with the AAT10 at the expense of a slightly lower sensitivity for most perinatal outcomes; these differences were not significant at the .05 level. Relative risk ratios were similar for the AAT6 and AAT10 for both fetal distress and neonatal morbidity, with both AAT being a more effective predictor of neonatal morbidity than for fetal distress. Both tests yielded better sensitivity when compared with NST.

CONCLUSIONS

Even though there was a nonsignificant trend toward higher sensitivities and lower specificities for the 10-minute AAT, this study showed that the differences in prediction of perinatal outcomes between the 6-minute and 10-minute AAT were minimal. In view of the added labor required for the 10-minute AAT in the absence of enhanced screening test validity, the 6-minute AAT is clinically preferred. This study has prompted new research questions for the continued development of the AAT as a low-technology fetal assessment technique with potential usefulness by midwives and their colleagues in a variety of settings worldwide.

Abstract B13: High-risk human papillomavirus prevalence in oral and oropharyngeal premalignant lesions: A critical literature review

Introduction: During the past decade, there has been a significant increase in the incidence of human papillomavirus (HPV) related squamous cell cancer of the oropharynx, especially those of the tonsil and tongue base. HPV-16 and HPV-18 have been linked to these malignant neoplasms. Generally, oral epithelium undergoes a sequence of histopathological pre-malignant transformations before the development of invasive carcinoma. A study evaluating the prevalence of HPV-16/18 types in histopathologically diagnosed oral pre-malignant lesions (OPL) is lacking. Therefore, we conducted a comprehensive literature review to estimate the prevalence of HR HPV types in different grades of OPLs.

Study Design: A critical literature search was conducted using Pubmed and SCOPUS databases for the key terms human papillomavirus infection, head and neck cancer, oral cancer, oral hyperplasia, oral dysplasia, and oral leukoplakia. A total of 90 articles related to HPV in oral tissue and pre-malignant lesions were identified. Of these, 29 articles evaluated the prevalence of HPV in histopathological OPLs (hyperplasia and dysplasia). In addition, 11 out of these 29 articles determined the prevalence of HPV in histologically evaluated leukoplakic samples. Only research articles published from 1990 — 2009 were used for this review.

Results: Overall, the 29 articles evaluated high-risk (HR) HPV in 1,171 OPLs. This included 140 hyperplasias, 467 dysplasias, 425 leukoplakic lesions without dysplasia, and 139 leukoplakic lesions with dysplasia. The prevalence of any type of HPV in hyperplasia, dysplasia, leukoplakia without dysplasia, and leukoplakia with dysplasia was 24%, 25%, 28%, and 20% respectively. The prevalence of HR HPV-16/18 in these lesions was 24%, 21%, 26% and 26% respectively. The difference in prevalence of different grades of OPLs was not statistically significant. The prevalence of any HPV type in mild, moderate, and severe dysplastic lesions was 43%, 39%, and 33% respectively. The prevalence of HR HPV-16/18 in mild, moderate, and severe dysplastic lesions was 39%, 32%, and 28% respectively.

Conclusion: High-risk HPV infection has been noted even in early stage histopathological OPLs like hyperplasias and mild dysplasias, and their prevalence rate is very similar to high grade OPLs, and oral (OC) and oropharyngeal cancers (OPC). Larger studies are needed to obtain a more precise estimate of the prevalence and persistence of HR HPV in histopathologically diagnosed OPLs in order to better understand the etiopathogenesis of HPV related OC and OPC.

Citation Information: Cancer Prev Res 2010;3(12 Suppl):B13.

From the female perspective: Long-term effects on quality of life of a program for women with asthma

BACKGROUND

Although, among adults, asthma predominates in women, the role of sex and gender in asthma has only recently been studied. Moreover, only one study has focused on the management of asthma by women, reporting that 1 year subsequent to an intervention addressing sex and gender role factors, women's asthma status was improved.

OBJECTIVE

Data from a 2-year postintervention follow-up were assessed to determine whether there were longer-term effects on the asthma status and quality of life (QoL) of the participants.

METHODS

A randomized controlled design was used in which female patients with asthma, who were receiving services at the University of Michigan Health System, Ann Arbor, Michigan (2002-2006), were assigned to either a control group or a female-oriented intervention group that focused on management challenges related to sex and gender role factors. Data were collected at baseline and 2 years' postintervention (2008) by telephone interview and review of medical records. Measures included asthma-related QoL, health care and medication use for asthma, level of self-regulation, self-confidence in managing the condition, sex and gender role-related asthma problems, and days of missed work or school because of asthma. Data were analyzed using both generalized estimating equations logistic regression and log-linear regression.

RESULTS

The mean (SD) age of the 808 women participating in the study was 48.2 (13.1) years in the intervention group and 48.7 (14.3) years in the control group, and the percentage of minority participants was 15.8% and 16.3%, respectively. Despite randomization, women in the intervention group had more persistent asthma at baseline. At 2 years' postrandomization, the only significant difference in health care use was associated with scheduled office visits; no other significant health care use differences were evident. However, the women in the intervention group had a significantly greater decrease of asthma symptoms with sexual activity (P = 0.01) and greater reduction in days of work/school missed for asthma in winter months (P = 0.03), were better able to self-regulate (P = 0.01), were more confident in managing their asthma (P = 0.01), and had higher levels of asthma-related QoL (P = 0.02). They also had a greater reduction in the use of short-acting bronchodilators (ie, rescue medications) than did women in the control group (P < or = 0.05).

CONCLUSION

An intervention that focuses on female-specific aspects of asthma management may result in improved QoL and health status for women with asthma, as was evident 2 years' postintervention in this study.

Yeast cell-wall products containing beta-glucan plus ascorbic acid affect neonatal Bos taurus calf leukocytes and growth after a transport stressor

The objectives were to ascertain whether a yeast cell-wall derivative that was 1.8% beta-glucan in combination with ascorbyl-2-polyphosphate could improve innate immunity and mediate transportation stress in neonatal calves, and to compare the 1.8% beta-glucan yeast cell-wall derivative with a more purified yeast cell-wall derivative (70% beta-glucan). Treatments were 1) an unsupplemented control (CNT); 2) 113 g of a 1.8% (approximately 2%) beta-glucan derivative of yeast cell walls plus 250 mg of l-ascorbic acid phosphate (BG2); or 3) 150 mg of a purified beta-glucan fraction from yeast cell walls (approximately 70% beta-glucan) plus 250 mg/feeding of l-ascorbic acid phosphate (BG70). Calves (n = 39) were transported for 4 h, placed in outdoor hutches, and randomly assigned to treatments. Treatments (mixed with a milk replacer) were individually fed twice daily for 28 d. Calves were offered calf starter, free choice, throughout the study. Weekly starter intake and BW were measured, and fecal samples were collected for Salmonella Typhimurium and Escherichia coli O157:H7 PCR analysis. Blood was collected immediately before transport (d 0) and on d 3, 7, 10, 14, 21, and 28 after transport. Starter intake and DMI were less (P < 0.05) at d 28 for the BG2 and BG70 treatments compared with the CNT treatment. Hematocrit percentages increased (P = 0.002) throughout the experiment. White blood cell counts (treatment x time interaction, P = 0.066) were less for the calves supplemented with BG70 than for those supplemented with BG2 (P = 0.01) or for CNT calves (P = 0.04) on d 28. Granulocyte counts changed (P = 0.04) throughout the experiment. A trend (P = 0.077) for a treatment x time interaction was detected for peripheral blood mononuclear cell counts (PBMC). Counts of PBMC were greater (P = 0.006) for the BG2 treatment compared with the CNT treatment on d 3. Calves given the BG70 supplement had fewer PBMC than those given the BG2 supplement on d 21 (P = 0.03) and 28 (P = 0.05). Fibrinogen concentrations were affected only by time (P = 0.002). Time effects were detected for phagocytosis (P = 0.005), oxidative burst (P < 0.001), expression of cluster of differentiation 18 (P = 0.001), and increased cluster of differentiation 18 (P = 0.006). Phagocytosis was less (P = 0.05) for calves in the BG70 group than for those in the CNT group. Percentage of calves positive for E. coli O157:H7 was greatest (P <or= 0.05) for those in the BG2 group on d 7 compared with those in the other treatments. The BG2 and BG70 supplements both increased feed intake, but only the BG2 supplement increased E. coli shedding on d 7, and the BG2 and BG70 supplements varied in modulating immune functions, indicating differences in yeast extract function.

Overweight women and management of asthma

PURPOSE

We sought to describe clinical and psychosocial characteristics of overweight women with asthma.

METHODS

Telephone interview and medical record review involving 808 women with asthma participating in a randomized study to identify those who were overweight. We assessed the relationship of their weight to asthma symptoms, health care use, quality of life, self-esteem, need for social support, and demographic characteristics. Regression analyses were used to investigate relationships between overweight and asthma.

FINDINGS

Sixty-eight percent of the women in the study were overweight or obese. Demographic characteristics associated with overweight in women with asthma included being minority (p=.000), having a lower education level (p=.000), and a lower household income (p=.024). Overweight was associated with greater health care use, comorbidities (acid reflux, urinary incontinence), and persistent disease (p=.001). Overweight women exhibited lower self-esteem (p=.002) and lower perceived quality of life (p=.000).

CONCLUSION

Overweight females with asthma experience significant challenges because of their weight, more persistent and severe disease, specific comorbidities, and lower rates of obtaining psychosocial resources. Clinical consultations and interventions should account for the influence of overweight on asthma control and health status in female patients.

Loss of the SMRT/NCoR2 corepressor correlates with JAG2 overexpression in multiple myeloma

Multiple myeloma (MM) is a clonal B-cell neoplasm that accounts for 10% of all malignant hematologic neoplasms and that affects terminally differentiated B cells (i.e., plasma cells). It is now well recognized that the cytokine interleukin-6 (IL-6) is a major cytokine that promotes the proliferation of malignant plasma cells in MM. The IL-6 gene can be regulated by the NOTCH genes products. We have previously shown that the NOTCH ligand, JAG2, is overexpressed in MM. To investigate the mechanism(s) leading to JAG2 overexpression in MM, we assessed potential epigenetic modifications of the JAG2 promoter. We showed that the JAG2 promoter region is aberrantly acetylated in MM cell lines and patient samples. The acetylation state of histones is regulated by the recruitment of histone deacetylases (HDAC). HDACs are typically recruited to promoter regions through interaction with nuclear corepressors such as SMRT. SMRT levels were therefore investigated. Interestingly, MM cell lines and patient samples presented significantly reduced SMRT levels. The experiments suggest a correlation between constitutive acetylation of the JAG2 core promoter in the MM cell lines and reduced levels of the SMRT corepressor that recruits HDAC to promoter regions. Finally, SMRT function restoration induced JAG2 down-regulation as well as MM cell apoptosis.