- Animal Behavior and Reproduction
- Avian ecology and behavior
- Hemoglobinopathies and Related Disorders
- Plant and animal studies
- Iron Metabolism and Disorders
- Childhood Cancer Survivors' Quality of Life
- Acute Lymphoblastic Leukemia research
- Wildlife Ecology and Conservation
- Botany and Plant Ecology Studies
- Bird parasitology and diseases
- Animal Ecology and Behavior Studies
- Animal Vocal Communication and Behavior
- Adolescent and Pediatric Healthcare
- Ecology and Vegetation Dynamics Studies
- Prenatal Screening and Diagnostics
- Folate and B Vitamins Research
- Viral gastroenteritis research and epidemiology
- Myeloproliferative Neoplasms: Diagnosis and Treatment
- Insect and Pesticide Research
- Rangeland and Wildlife Management
- Genetic and phenotypic traits in livestock
- Cancer Risks and Factors
- Species Distribution and Climate Change
- Multiple and Secondary Primary Cancers
- Epigenetics and DNA Methylation
St. Jude Children's Research Hospital
2009-2025
University of Memphis
2015-2024
Campbell Clinic
2022
University of Tennessee at Knoxville
2022
Baptist Memorial Health Care
2019
University of Tennessee Health Science Center
2019
Donaldson (United States)
2011
The University of Texas MD Anderson Cancer Center
2011
Helen DeVos Children's Hospital
2009
Fred Hutch Cancer Center
2009
We approach conceptual issues in evolutionary biology from an endocrinological perspective, noting that single hormones typically act on several target tissues and thereby mediate suites of correlated phenotypic traits. When components such a suite are beneficial, important question is whether all adaptations or some exaptations. The answer may depend the traits arose response to selection variation systemic levels hormone responsiveness invariant hormone. If former, probably acted directly...
This article, which focuses on hormones and the diverse effects they have behavior physiology, raises evolutionary questions that hormonal studies appear especially well suited to address. These include endocrine basis for life-history trade-offs, role of in adaptive alterations social organization mating systems, whether natural selection acts traits or organisms. The article also shows how phenotypic engineering by manipulations can reveal significance variation. By generating rare novel...
Hormones influence many aspects of organismal behavior, physiology, and morphology, thus hormones may lie at the root life-history trade-offs. By manipulating we can create novel phenotypes (i.e., perform phenotypic engineering) attempt to relate variation fitness. We report effect testosterone treatment on parental behavior vocal adult male dark-eyed juncos. Testosterone partially suppressed paternal increased frequency song. When compared treated males controls for nine potential...
Abstract Background Estimation of the risk adverse long‐term outcomes such as second malignant neoplasms and infertility often requires reproducible quantification exposures. The method for should be easily utilized valid across different study populations. widely used Alkylating Agent Dose (AAD) score is derived from drug dose distribution population thus cannot comparisons populations each will have a unique doses. Methods We compared performance Cyclophosphamide Equivalent (CED), unit...
The sex ratio of Dark—eyed Juncos wintering in the eastern and central United States Canada varies clinally along a latitudinal gradient. percentage @V among both museum skins live—caught birds is °70% south, 20% north. When abundance according to latitude also considered, an average ♀ appears winter farther south than ♂ hence probably tends migrate farther. Latitude alone excellent predictor (r 2 = 85%), plus 13 other measures climate explain virtually all variation 96.6%). Extreme climate,...
When selection on males and females differs, the sexes may diverge in phenotype. Hormones serve as a proximate regulator of sex differences by mediating sex-biased trait expression. To integrate these perspectives, we consider how suites traits mediated same hormone both might respond to selection. In male birds, plasma testosterone (T) varies seasonally among species according mating system. elevated experimentally, it is known enhance some components fitness decrease others. We report that...
Understanding physiological and behavioral mechanisms underlying the diversity of observed life-history strategies is challenging because difficulties in obtaining long-term measures fitness relating to these mechanisms. We evaluated effects experimentally elevated testosterone on male a population dark-eyed juncos studied over nine breeding seasons using demographic modeling approach. Elevated levels decreased survival rates but increased success producing extra-pair offspring. Higher...
Abstract Background To facilitate prospective medical assessment of adults surviving pediatric malignancies and advance knowledge about long‐term childhood cancer survivor health, St. Jude Children's Research Hospital (SJCRH) is establishing a lifetime cohort survivors. Methods Eligibility criteria for inclusion in the Lifetime Cohort (SJLIFE) study include: (1) diagnosis malignancy treated at SJCRH; (2) survival ≥ 10 years from diagnosis; (3) current age ≥18 years. Three levels...
Monogamous and polygynous male songbirds generally differ in their breeding season profiles of circulating testosterone. Testosterone level spikes early the monogamists then declines, but it remains high polygynists. Male dark-eyed juncos (Junco hyemalis) are socially monogamous exhibit usual pattern, experimental maintenance testosterone throughout alters normal behavior physiology affects various components annual reproductive success not overall success. Because stabilizing selection...
Male parental care is rare in most groups of animals but common birds. Among birds considerable variation exists the form provided their young; recent developments several areas may help to explain this variation. These include (i) improvements comparative method, particularly use phylogenies investig ate questions about evolution (origin) behavior; (ii) field studies designed determine fitness benefits and selective factors that maintain it; (iii) investigations
Perhaps the best way to determine whether and how traits of organisms are currently adaptive is alter them experimentally compare relative fitness altered unaltered individuals. We call this method phenotypic engineering. To extent that natural selection moulds on a trait‐by‐trait basis, we would expect unmanipulated (control) individuals be higher than However, other outcomes possible interest. If, for example, single trait were manipulated found similar, might conclude not operating trait....
Pulmonary complications of sickle cell anemia (Hb-SS) commonly cause morbidity, yet few large studies pulmonary function tests (PFTs) in this population have been reported.PFTs (spirometry, lung volumes, and diffusion capacity for carbon monoxide [DLCO]) from 310 adults with Hb-SS were analyzed to determine the pattern dysfunction their association other systemic disease.Raw PFT data compared predicted values. Each subject was subclassified into one five groups: obstructive physiology,...
Monogamous male birds typically allocate less effort to courtship and more parental behaviour than males of polygynous species. The seasonal pattern testosterone (T) secretion varies accordingly. exhibit a spring peak in plasma T followed by lower levels during the phase, while species continue court females maintain at higher levels. To determine whether underlies trade–off between mating effort, we treated dark–eyed juncos (Junco hyemalis) with exogenous compared reproductive success (RS)...
BackgroundIntravascular hemolysis in sickle cell anemia could contribute to complications associated with nitric oxide deficiency, advancing age, and increased mortality. We have previously reported that intense is risk of vascular a small cohort adults disease. These observations not been validated other populations.MethodsThe distribution serum lactic dehydrogenase (LDH) values was used as surrogate measure intravascular contemporaneous patient group an historical adult population from the...
Cutaneous leg ulcers are common in sickle cell anaemia and their risk might be genetically determined. Sickle patients were studied to examine the relationship of with haemolysis single nucleotide polymorphisms (SNPs) candidate genes that could affect vasoocclusion. Leg ulcer had lower haemoglobin levels higher lactate dehydrogenase, bilirubin, aspartate transaminase reticulocytes than did control but without ulcers. Age-adjusted comparisons showed anaemia-alpha thalassaemia was more...
Young adult survivors of childhood brain tumors (BTs) may have late effects that compromise physical performance and everyday task participation. The objective this study was to evaluate muscle strength, fitness, performance, participation among BTs.In-home evaluations interviews were conducted for 156 participants (54% men). Results on measures compared between BT members a population-based comparison group by using chi-square statistics 2-sample t tests. Associations evaluated in...