Creating Culturally Adapted Multilingual Materials for Research.

Patients who speak languages other than English are frequently excluded from research. This exclusion exacerbates inequities, biases results, and may violate federal regulations and research ethics. Language justice is the right to communicate in an individual's preferred language to address power imbalances and promote equity. To promote language justice in research, we propose a method to translate and culturally-adapt multifaceted research materials into multiple languages simultaneously. Our method involves a multistep approach, including professional translation, review by bilingual expert panels to refine and reach consensus, and piloting or cognitive interviews with patients and families. Key differences from other translation approaches (eg, the World Health Organization) include omitting back-translation, given its limited utility in identifying translation challenges, and limiting expert panelist and piloting-participant numbers for feasibility. We detail a step-by-step approach to operationalizing this method and outline key considerations learned after utilizing this method to translate materials into 8 languages other than English for an ongoing multicenter pediatric research study on family safety-reporting. Materials included family brochures, surveys, and intervention materials. This approach took ∼6 months overall at a cost of <$2000 per language (not including study personnel costs). Key themes across the project included (1) tailor scope to timeline, budget, and resources, (2) thoughtfully design English source materials, (3) identify and apply guiding principles throughout the translation and editing process, and (4) carefully review content and formatting to account for nuances across multiple languages. This method balances feasibility and rigor in translating participant-facing materials into multiple languages simultaneously, advancing language justice in research.

ISPAD ANNUAL CONFERENCE HIGHLIGHTS 2023.

The 49th Annual Conference of the International Society of Pediatric and Adolescent Diabetes (ISPAD), held from October 18 to 21, 2023, in Rotterdam, Netherlands, showcased significant advancements and diversity in paediatric and adolescent diabetes research and clinical innovations. The conference, renowned for its global impact, brought together experts to discuss cutting-edge developments in the field. Highlights from the plenary sessions included ground-breaking research on immunotherapies and diabetes technologies and offering new insights into personalised treatment approaches. Keynote speakers emphasised the importance of early diagnosis, prevention and the potential of novel biomarkers in predicting disease progression. The symposia covered a broad spectrum of topics, from advancements in continuous glucose monitoring technologies to the latest in hybrid closed loop systems which promise to revolutionise diabetes management for young patients.

Clinical and sociodemographic factors associated with the quality of life of children and adolescents with type 1 diabetes.

OBJECTIVE: To analyze clinical and sociodemographic factors associated with the health-related quality of life of children and adolescents with type 1 Diabetes Mellitus. METHOD: A quantitative, cross-sectional and analytical study, developed in a municipality in northeastern Brazil, between March and September 2021, with 81 children/adolescents with type 1 Diabetes Mellitus and their guardians/caregivers. A questionnaire containing sociodemographic and clinical variables and two quality of life instruments were used. Descriptive and inferential analysis was carried out. RESULTS: Adolescents whose parents had a family income greater than a minimum wage had a lower prevalence of impaired quality of life when compared to those with a lower income. Adolescents with time since diagnosis of less than four years had a satisfactory quality of life, and children aged 8 to 12 years who self-administered insulin had a lower prevalence of high quality of life compared to those who did not. CONCLUSION: Adolescents with a family income of less than a minimum wage, diagnosis time of more than four years and children aged 8-12 who self-administer insulin need greater professional support to have a better quality of life.

Effects of Macronutrient Intake and Number of Meals on Glycemic Outcomes Over 1 Year in Youth with Type 1 Diabetes.

Objective: Insulin bolus doses derive from glucose levels and planned carbohydrate intake, although fat and protein impact glycemic excursions. We examined the impact of macronutrients and number of daily meals/snacks on glycemic outcomes in youth with type 1 diabetes. Methods: Youth (N = 136, ages 8-17) with type 1 diabetes completed 3-day food records, wore 3-day masked continuous glucose monitoring, and had A1c measurements every 3 months for 1 year. Diet data were analyzed using Nutrition Data System for Research. Longitudinal mixed models assessed effects of macronutrient intake and number of meals/snacks on glycemic outcomes. Results: At baseline, youth (48% male) had mean age of 12.8 ± 2.5 years and diabetes duration of 5.9 ± 3.1 years; 73% used insulin pumps. Baseline A1c was 8.1% ± 1.0%, percent time in range 70-180 mg/dL (%TIR) was 49% ± 17%, % time below range <70 mg/dL (%TBR) was 6% ± 8%, % time above range >180 mg/dL (%TAR) was 44% ± 20%, and glycemic variability as coefficient of variation (CV) was 41% ± 8%; macronutrient intake included 48% ± 5% carbohydrate, 36% ± 5% fat, and 16% ± 2% protein. Most youth (56%) reported 3-4 meals/snacks daily (range 1-9). Over 1 year, greater carbohydrate intake was associated with lower A1c (P = 0.0003), more %TBR (P = 0.0006), less %TAR (P = 0.002), and higher CV (P = 0.03). Greater fat intake was associated with higher A1c (P = 0.006), less %TBR (P = 0.002), and more %TAR (P = 0.005). Greater protein intake was associated with higher A1c (P = 0.01). More daily meals/snacks were associated with lower A1c (P = 0.001), higher %TIR (P = 0.0006), and less %TAR (P = 0.0001). Conclusions: Both fat and protein impact glycemic outcomes. Future automated insulin delivery systems should consider all macronutrients for timely insulin provision. The present research study derived from secondary analysis of the study registered under NCT00999375.

Prototyping Process and Usability Testing of a Serious Game for Brazilian Children With Type 1 Diabetes.

This study aims to describe the prototype development and testing of a serious game designed for Brazilian children with diabetes. Following an approach of user-centered design, the researchers assessed game's preferences and diabetes learning needs to develop a Paper Prototype. The gameplay strategies included diabetes pathophysiology, self-care tasks, glycemic management, and food group learning. Diabetes and technology experts (n = 12) tested the prototype during audio-recorded sessions. Next, they answered a survey to evaluate the content, organization, presentation, and educational game aspects. The prototype showed a high content validity ratio (0.80), with three items not achieving the critical values (0.66). Experts recommended improving the game content and food illustrations. This evaluation contributed to the medium-fidelity prototype version, which after testing with diabetes experts (n = 12) achieved high content validity values (0.88). One item did not meet the critical values. Experts suggested increasing the options of outdoor activities and meals. Researchers also observed and video-recorded children with diabetes (n = 5) playing the game with satisfactory interaction. They considered the game enjoyable. The interdisciplinary team plays an important role guiding the designers in the use of theories and real needs of children. Prototypes are a low-cost usability and a successful method for evaluating games.

Glycemic outcomes of people with diabetes mellitus in Brazilian primary health care.

Background: The capillary blood glucose monitoring program at home a challenge in primary health care. Therefore, it is fundamental to identify the glycemic control of people with diabetes mellitus through HBA1c and to analyze its associated factors. Objective: To identify the glycemic profile of people with Diabetes Mellitus (DM) through HbA1c and analyze factors associated. Materials & methods: Cross-sectional study developed in Ribeirão Preto, São Paulo, Brazil. Secondary data from the electronic health record of people registered in the Primary Health Care system were used. A sample of 3181 participants was obtained. People with HbA1c < 7.0% (53 mmol/mol) were considered to have adequate glycemic control. For people aged ≥ 55 years, a less stringent target, < 8.0% (64 mmol/mol), was also considered. The odds ratio was the measure of effect analyzed with their respective 95% Confidence Intervals (95% CI). Results: Adequate glycemic control with HbA1c < 7.0% (53 mmol/mol) was found in 44.8% of people and, when using the less rigid target, HbA1c < 8.0% (64 mmol/mol) for people aged ≥ 55 years-old, 70.6% had adequate glycemic control. Age and drug therapy were associated with adequate glycemic control (p < 0.001), which was more frequent among older people and those who used only metformin. Conclusion: The study shows that the achievement of adequate glycemic control is still a challenge, especially with regard to younger people and those who use insulin.

Clinical and sociodemographic factors associated with the quality of life of children and adolescents with type 1 diabetes / Factores clínicos y sociodemográficos asociados a la calidad de vida de niños y adolescentes con diabetes tipo 1 / Fatores clínicos e sociodemográficos associados à qualidade de vida do público infantojuvenil com diabetes tipo 1

ABSTRACT Objective: To analyze clinical and sociodemographic factors associated with the health-related quality of life of children and adolescents with type 1 Diabetes Mellitus. Method: A quantitative, cross-sectional and analytical study, developed in a municipality in northeastern Brazil, between March and September 2021, with 81 children/adolescents with type 1 Diabetes Mellitus and their guardians/caregivers. A questionnaire containing sociodemographic and clinical variables and two quality of life instruments were used. Descriptive and inferential analysis was carried out. Results: Adolescents whose parents had a family income greater than a minimum wage had a lower prevalence of impaired quality of life when compared to those with a lower income. Adolescents with time since diagnosis of less than four years had a satisfactory quality of life, and children aged 8 to 12 years who self-administered insulin had a lower prevalence of high quality of life compared to those who did not. Conclusion: Adolescents with a family income of less than a minimum wage, diagnosis time of more than four years and children aged 8-12 who self-administer insulin need greater professional support to have a better quality of life.

RESUMEN Objetivo: Analizar los factores clínicos y sociodemográficos asociados a la calidad de vida relacionada con la salud de niños y adolescentes con Diabetes Mellitus tipo 1. Método: Estudio cuantitativo, transversal y analítico, desarrollado en un municipio del Nordeste brasileño, entre marzo y septiembre de 2021, con 81 niños/adolescentes con Diabetes Mellitus tipo 1 y sus tutores/cuidadores. Se utilizó un cuestionario que contenía variables sociodemográficas y clínicas y dos instrumentos de calidad de vida. Se realizó análisis descriptivo e inferencial. Resultados: los adolescentes cuyos padres tenían un ingreso familiar superior a un salario mínimo tuvieron una menor prevalencia de deterioro de la calidad de vida en comparación con aquellos con menores ingresos. Los adolescentes con un tiempo de diagnóstico menor a cuatro años tuvieron una calidad de vida satisfactoria, y los niños de 8 a 12 años que se autoadministraron insulina tuvieron una menor prevalencia de alta calidad de vida en comparación con los que no lo hicieron. Conclusión: Los adolescentes con ingreso familiar menor a un salario mínimo, tiempo de diagnóstico mayor a cuatro años y niños de 8 a 12 años que se autoadministran insulina necesitan mayor apoyo profesional para tener una mejor calidad de vida.

RESUMO Objetivo: Analisar os fatores clínicos e sociodemográficos associados à qualidade de vida relacionada à saúde de crianças e adolescentes com Diabetes Mellitus tipo 1. Método: Estudo quantitativo, transversal e analítico, desenvolvido em um município do Nordeste brasileiro, entre março e setembro de 2021, com 81 crianças/adolescentes com Diabetes Mellitus tipo 1 e seus responsáveis/cuidadores. Utilizaram-se um questionário contendo as variáveis sociodemográficas e clínicas e dois instrumentos de qualidade de vida. Realizou-se análise descritiva e inferencial. Resultados: Adolescentes cujos pais tinham renda familiar superior a um salário mínimo apresentaram prevalência menor de qualidade de vida prejudicada, quando comparados àqueles com renda inferior. Adolescentes com tempo de diagnóstico menor que quatro anos apresentaram qualidade de vida satisfatória, e crianças de 8 a 12 anos que faziam autoaplicação de insulina apresentaram prevalência menor de qualidade de vida alta em relação às que não realizavam. Conclusão: Adolescentes com renda familiar inferior a um salário mínimo, tempo de diagnóstico superior a quatro anos e crianças de 8-12 anos que realizam autoaplicação de insulina necessitam de maior suporte profissional para ter melhor qualidade de vida.

Emergency Fostering of Dogs From Animal Shelters During the COVID-19 Pandemic: Shelter Practices, Foster Caregiver Engagement, and Dog Outcomes.

Each year, millions of dogs enter thousands of animal shelters across the United States. Life in the shelter can be stressful, and one type of intervention that improves dogs' experience is human interaction, particularly stays in foster homes. Prior research has demonstrated that fostering can reduce dogs' cortisol and increase their resting activity. Despite these benefits, little is understood about the utilization of foster caregiving in animal shelters, and even less so during a crisis. On March 11, 2020, the World Health Organization deemed the coronavirus outbreak a worldwide pandemic, and subsequently a nationwide emergency was declared in the United States. Nearly all states issued stay-at-home orders to curb the spread of the virus. During this time, media outlets reported increased interest in the adoption and fostering of shelter pets. This study explores canine foster caregiving at 19 US animal shelters during the first 4 months of the COVID-19 pandemic. In our investigation, we found that shelters' utilization of foster caregiving increased from March to April 2020 but returned to initial pandemic levels by June 2020. Slightly less than two-fifths of foster caregivers were community members with no prior relationship with the shelter, and these caregivers were over four times more likely to adopt their fostered dogs than those with a pre-existing relationship to the shelter. Individuals fostering with the intention to adopt, in fact, adopted their dogs in nearly three-quarters of those instances. With regards to shelters' available resources, we found that very low-resource shelters relied more heavily on individuals with prior relationships to provide foster caregiving while very high-resource shelters more often recruited new community members. We also found that our lowest resourced shelters transferred more dogs out of their facilities while more resourced shelters rehomed dogs directly to adopters. To our knowledge, these findings represent the first in-depth reporting about dog fostering in US animal shelters and, more specifically, foster caregiving during the COVID-19 pandemic. In total, they provide greater understanding of how monetary and human resources were utilized to affect the care and ultimately, the outcomes of shelter dogs during this time.

Application of Chitosan Microparticles against Human Norovirus.

ABSTRACT: Human norovirus (HuNoV) is the leading cause of foodborne illness outbreaks and the second most common cause of waterborne infections in the United States. The goal of this research was to investigate the antiviral activity of chitosan microparticles (CMs) against HuNoV GII.4 Sydney and its cultivable surrogate Tulane virus (TuV) in suspensions mimicking fecally contaminated water. CMs were prepared by cross-linking chitosan molecules with sodium sulfate, and the antiviral activity of CMs was assessed with an infectivity assay on TuV and by quantitative reverse transcription PCR on TuV and HuNoV. A 3% CM suspension in phosphate-buffered saline (pH 7.2) bound to TuV particles but had a negligible impact on virus infectivity (P > 0.05). A 10-min contact time resulted in a 1.5-log reduction in genomic copies per mL of TuV and HuNoV in fecal suspensions (P < 0.05). Despite the negligible impact on viral infectivity, CMs can moderately bind to infectious virus particles and help purify environmental water by removing these particles. In this study, TuV was a suitable surrogate for HuNoV with similar log reductions in fecal suspension. These findings highlight the potential application of CM as a novel treatment to minimize the spread of waterborne viral pathogens.

Development of a Histopathology Informatics Pipeline for Classification and Prediction of Clinical Outcomes in Subtypes of Renal Cell Carcinoma.

PURPOSE: Histopathology evaluation is the gold standard for diagnosing clear cell (ccRCC), papillary, and chromophobe renal cell carcinoma (RCC). However, interrater variability has been reported, and the whole-slide histopathology images likely contain underutilized biological signals predictive of genomic profiles. EXPERIMENTAL DESIGN: To address this knowledge gap, we obtained whole-slide histopathology images and demographic, genomic, and clinical data from The Cancer Genome Atlas, the Clinical Proteomic Tumor Analysis Consortium, and Brigham and Women's Hospital (Boston, MA) to develop computational methods for integrating data analyses. Leveraging these large and diverse datasets, we developed fully automated convolutional neural networks to diagnose renal cancers and connect quantitative pathology patterns with patients' genomic profiles and prognoses. RESULTS: Our deep convolutional neural networks successfully detected malignancy (AUC in the independent validation cohort: 0.964-0.985), diagnosed RCC histologic subtypes (independent validation AUCs of the best models: 0.953-0.993), and predicted stage I ccRCC patients' survival outcomes (log-rank test P = 0.02). Our machine learning approaches further identified histopathology image features indicative of copy-number alterations (AUC > 0.7 in multiple genes in patients with ccRCC) and tumor mutation burden. CONCLUSIONS: Our results suggest that convolutional neural networks can extract histologic signals predictive of patients' diagnoses, prognoses, and genomic variations of clinical importance. Our approaches can systematically identify previously unknown relations among diverse data modalities.

Investigating the Impact of Brief Outings on the Welfare of Dogs Living in US Shelters.

Social isolation likely contributes to reduced welfare for shelter-living dogs. Several studies have established that time out of the kennel with a person can improve dogs' behavior and reduce physiological measures of stress. This study assessed the effects of two-and-a-half-hour outings on the urinary cortisol levels and activity of dogs as they awaited adoption at four animal shelters. Dogs' urine was collected before and after outings for cortisol:creatinine analysis, and accelerometer devices were used to measure dogs' physical activity. In total, 164 dogs participated in this study, with 793 cortisol values and 3750 activity measures used in the statistical analyses. We found that dogs' cortisol:creatinine ratios were significantly higher during the afternoon of the intervention but returned to pre-field trip levels the following day. Dogs' minutes of low activity were significantly reduced, and high activity significantly increased during the outing. Although dogs' cortisol and activity returned to baseline after the intervention, our findings suggest that short-term outings do not confer the same stress reduction benefits as previously shown with temporary fostering. Nevertheless, it is possible that these types of outing programs are beneficial to adoptions by increasing the visibility of dogs and should be further investigated to elucidate these effects.

A functional genomics screen identifying blood cell development genes in Drosophila by undergraduates participating in a course-based research experience.

Undergraduate students participating in the UCLA Undergraduate Research Consortium for Functional Genomics (URCFG) have conducted a two-phased screen using RNA interference (RNAi) in combination with fluorescent reporter proteins to identify genes important for hematopoiesis in Drosophila. This screen disrupted the function of approximately 3500 genes and identified 137 candidate genes for which loss of function leads to observable changes in the hematopoietic development. Targeting RNAi to maturing, progenitor, and regulatory cell types identified key subsets that either limit or promote blood cell maturation. Bioinformatic analysis reveals gene enrichment in several previously uncharacterized areas, including RNA processing and export and vesicular trafficking. Lastly, the participation of students in this course-based undergraduate research experience (CURE) correlated with increased learning gains across several areas, as well as increased STEM retention, indicating that authentic, student-driven research in the form of a CURE represents an impactful and enriching pedagogical approach.

A canine identity crisis: Genetic breed heritage testing of shelter dogs.

Previous research in animal shelters has determined the breeds of dogs living in shelters by their visual appearance; however the genetic breed testing of such dogs is seldom conducted, and few studies have compared the breed labels assigned by shelter staff to the results of this testing. In the largest sampling of shelter dogs' breed identities to-date, 459 dogs at Arizona Animal Welfare League & SPCA (AAWL) in Phoenix, Arizona, and 460 dogs at San Diego Humane Society & SPCA (SDHS) in San Diego, California, were genetically tested using a commercially available product to determine their breed heritage. In our sample, genetic analyses identified 125 distinct breeds with 91 breeds present at both shelters, and 4.9% of the dogs identified as purebreds. The three most common breed signatures, in order of prevalence, American Staffordshire Terrier, Chihuahua, and Poodle, accounted for 42.5% or all breed identifications at the great grandparent level. During their stay at the shelter, dogs with pit bull-type ancestries waited longer to be adopted than other dogs. When we compared shelter breed assignment as determined by visual appearance to that of genetic testing, staff at SDHS was able to successfully match at least one breed in the genetic heritage of 67.7% of dogs tested; however their agreement fell to 10.4% when asked to identify more than one breed. Lastly, we found that as the number of pit bull-type relatives in a dog's heritage increased, so did the shelter's ability to match the results of DNA analysis. In total when we consider the complexity of shelter dog breed heritage and the failure to identify multiple breeds based on visual identification coupled with our inability to predict how these breeds then interact within an individual dog, we believe that focusing resources on communicating the physical and behavioral characteristics of shelter dogs would best support adoption efforts.

Measuring and Improving Physician Knowledge of Safety Risks Using Traditional and Online Methods in Pharmacovigilance.

BACKGROUND: Traditional methods for assessing prescriber knowledge can take several years to deliver results. This study was undertaken to obtain insights into the potential for using existing online communities to educate prescribers on therapy-related safety risks. OBJECTIVE: The aim of this study was to describe approaches to measuring prescribers' knowledge of safety risk (osteonecrosis of the jaw) outlined in the European Medicine Agency's summary of product characteristics for denosumab (XGEVA®). METHODS: Short multiple-choice online instruments were administered as (1) a two-round cross-sectional survey fielded in January 2013-May 2015 (traditional, nine European countries, study duration: 3 years), (2) a survey targeting the online Medscape community (seven European countries, study duration: 3 weeks), and (3) a continuing medical education module with pre-/post-assessment in an online Medscape community (Medscape Education, USA). All respondents were oncologists; treated five or more patients with bone metastases from solid tumours in the previous 3 months; and prescribed denosumab within the previous 12 months. Medscape (a WebMD company, New York, NY, USA) is the leading online medical information resource, serving approximately 3 million physicians worldwide and 400,000 within Europe. RESULTS: In the traditional 29-month study, 420 (n = 210 per round; 14% of screened physicians) individuals participated. Knowledge levels exceeded 75% correct on five questions (incidence of osteonecrosis of the jaw, concomitant risk factors and prevention of osteonecrosis of the jaw during denosumab treatment, importance of ensuring oral hygiene, and care for patients who have or develop osteonecrosis of the jaw) with less awareness of optimal osteonecrosis of the jaw treatment. The Medscape survey (n = 207; 32.1% of 645 eligible) provided similar results in a 3-week post-survey launch. The Medscape Education study (n = 264) documented knowledge acquisition. CONCLUSIONS: Assessments that target physicians through online platforms where they seek information about drug-related safety risks may result in increased efficiencies, informing regulators about prescribers' knowledge of safe use within weeks rather than years. Online communities or professional societies may provide venues in which to implement knowledge-acquisition surveys tied to training/education modules that address safety topics.

What's in a Name? Effect of Breed Perceptions & Labeling on Attractiveness, Adoptions & Length of Stay for Pit-Bull-Type Dogs.

Previous research has indicated that certain breeds of dogs stay longer in shelters than others. However, exactly how breed perception and identification influences potential adopters' decisions remains unclear. Current dog breed identification practices in animal shelters are often based upon information supplied by the relinquishing owner, or staff determination based on the dog's phenotype. However, discrepancies have been found between breed identification as typically assessed by welfare agencies and the outcome of DNA analysis. In Study 1, the perceived behavioral and adoptability characteristics of a pit-bull-type dog were compared with those of a Labrador Retriever and Border Collie. How the addition of a human handler influenced those perceptions was also assessed. In Study 2, lengths of stay and perceived attractiveness of dogs that were labeled as pit bull breeds were compared to dogs that were phenotypically similar but were labeled as another breed at an animal shelter. The latter dogs were called "lookalikes." In Study 3, we compared perceived attractiveness in video recordings of pit-bull-type dogs and lookalikes with and without breed labels. Lastly, data from an animal shelter that ceased applying breed labeling on kennels were analyzed, and lengths of stay and outcomes for all dog breeds, including pit bulls, before and after the change in labeling practice were compared. In total, these findings suggest that breed labeling influences potential adopters' perceptions and decision-making. Given the inherent complexity of breed assignment based on morphology coupled with negative breed perceptions, removing breed labels is a relatively low-cost strategy that will likely improve outcomes for dogs in animal shelters.

Stability of within-host-parasite communities in a wild mammal system.

Simultaneous infection by multiple parasite species is ubiquitous in nature. Interactions among co-infecting parasites may have important consequences for disease severity, transmission and community-level responses to perturbations. However, our current view of parasite interactions in nature comes primarily from observational studies, which may be unreliable at detecting interactions. We performed a perturbation experiment in wild mice, by using an anthelminthic to suppress nematodes, and monitored the consequences for other parasite species. Overall, these parasite communities were remarkably stable to perturbation. Only one non-target parasite species responded to deworming, and this response was temporary: we found strong, but short-lived, increases in the abundance of Eimeria protozoa, which share an infection site with the dominant nematode species, suggesting local, dynamic competition. These results, providing a rare and clear experimental demonstration of interactions between helminths and co-infecting parasites in wild vertebrates, constitute an important step towards understanding the wider consequences of similar drug treatments in humans and animals.

Response of the Strongyloides ratti transcriptome to host immunological environment.

The immunological environment experienced by parasitic nematodes varies greatly between hosts and is particularly influenced by whether or not a host has been previously infected. How a parasitic nematode responds to these different environments is poorly understood, but may allow a parasite to ameliorate the adverse effects of host immunity on parasite fitness. Here we use a microarray approach to identify genes in the parasitic nematode Strongyloides ratti that exhibit differential transcription between different rat host immunological environments, and between replicate lines of S. ratti selected for either early or late reproduction. We hypothesise that such genes may be used by this species to cope with and respond to its host environment. Our results showed that, despite large phenotypic differences between S. ratti adults from different immunological environments, the S. ratti transcriptome exhibited a relatively stable pattern of expression. Thus, differential expression amongst treatments was limited to a small proportion of transcripts and generally involved only modest fold changes. These transcripts included a group of collagen genes up-regulated in parasites early in an infection, and in immunised host environments, which may be related to protection against the damage caused to a parasite by host immune responses. We found that later in an infection, a number of genes associated with muscle function and repair were up-regulated in immunised host environments; these may help parasites maintain their position in the host intestine. Differences in transcription between selection lines of S. ratti were only observed in immunised hosts and included genes associated with the response to the host's immunological environment.

Experimental evolution of parasite life-history traits in Strongyloides ratti (Nematoda).

Evolutionary ecology predicts that parasite life-history traits, including a parasite's survivorship and fecundity within a host, will evolve in response to selection and that their evolution will be constrained by trade-offs between traits. Here, we test these predictions using a nematode parasite of rats, Strongyloides ratti, as a model. We performed a selection experiment by passage of parasite progeny from either early in an infection ('fast' lines) or late in an infection ('slow' lines). We found that parasite fecundity responded to selection but that parasite survivorship did not. We found a trade-off mediated via conspecific density-dependent constraints; namely, that fast lines exhibit higher density-independent fecundity than slow lines, but fast lines suffered greater reduction in fecundity in the presence of density-dependent constraints than slow lines. We also found that slow lines both stimulate a higher level of IgG1, which is a marker for a Th2-type immune response, and show less of a reduction in fecundity in response to IgG1 levels than for fast lines. Our results confirm the general prediction that parasite life-history traits can evolve in response to selection and indicate that such evolutionary responses may have significant implications for the epidemiology of infectious disease.