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At least 73 records · Page 4

Whole Lung Irradiation for Adults With Pulmonary Metastases From Ewing Sarcoma

Purpose: To evaluate feasibility and patterns of failure in adult patients with Ewing sarcoma (ES) treated with whole lung irradiation (WLI) for pulmonary metastases. Methods and Materials: Retrospective review of all ES patients treated at age 18 or older with 12-15 Gy WLI for pulmonary metastases at a single institution between 1990 and 2014. Twenty-six patients met the study criteria. Results: The median age at WLI was 23 years (range, 18-40). The median follow-up time of the surviving patients was 3.8 years (range, 1.0-9.6). The 3-year cumulative incidence of pulmonary relapse (PR) was 55%, with a 3-year cumulative incidence of PR as the site of first relapse of 42%. The 3-year event-free survival (EFS) and overall survival (OS) were 38 and 45%, respectively. Patients with exclusively pulmonary metastases had better outcomes than did those with extrapulmonary metastases: the 3-year PR was 45% in those with exclusively lung metastases versus 76% in those with extrapulmonary metastases (P=.01); the 3-year EFS was 49% versus 14% (P=.003); and the 3-year OS was 61% versus 13% (P=.009). Smoking status was a significant prognostic factor for EFS: the 3-year EFS was 61% in nonsmokers versus 11% in smokers (P=.04). Two patients experienced herpes zoster in the radiation field 6 and 12 weeks after radiation. No patients experienced pneumonitis or cardiac toxicity, and no significant acute or late sequelae were observed among the survivors. Conclusion: WLI in adult patients with ES and lung metastases is well tolerated and is associated with freedom from PR of 45% at 3 years. Given its acceptable toxicity and potential therapeutic effect, WLI for pulmonary metastases in ES should be considered for adults, as it is in pediatric patients. All patients should be advised to quit smoking before receiving WLI.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

MO-FG-CAMPUS-IeP2-03: Validation of an SSDE-To-Organ-Dose Calculation Methodology Developed for Pediatric CT in An Adult Population

Purpose: To discover if a previously published methodology for estimating patient-specific organ dose in a pediatric population (5–55kg) is translatable to the adult sized patient population (> 55 kg). Methods: An adult male anthropomorphic phantom was scanned with metal oxide semiconductor field effect transistor (MOSFET) dosimeters placed at 23 organ locations in the chest and abdominopelvic regions to determine absolute organ dose. Organ-dose-to-SSDE correlation factors were developed by dividing individual phantom organ doses by SSDE of the phantom; where SSDE was calculated at the center of the scan volume of the chest and abdomen/pelvis separately. Organ dose correlation factors developed in phantom were multiplied by 28 chest and 22 abdominopelvic patient SSDE values to estimate organ dose. The median patient weight from the CT examinations was 68.9 kg (range 57–87 kg) and median age was 17 years (range 13–28 years). Calculated organ dose estimates were compared to published Monte Carlo simulated patient and phantom results. Results: Organ-dose-to-SSDE correlation was determined for a total of 23 organs in the chest and abdominopelvic regions. For organs fully covered by the scan volume, correlation in the chest (median 1.3; range 1.1–1.5) and abdominopelvic (median 0.9; range 0.7–1.0) was 1.0 ± 10%. For organs that extended beyond the scan volume (i.e. skin bone marrow and bone surface) correlation was determined to be a median of 0.3 (range 0.1–0.4). Calculated patient organ dose using patient SSDE agreed to better than 6% (chest) and 15% (abdominopelvic) to published values. Conclusion: This study demonstrated that our previous published methodology for calculating organ dose using patient-specific SSDE for the chest and abdominopelvic regions is translatable to adult sized patients for organs fully covered by the scan volume.

60 APPLIED LIFE SCIENCES↗

The examination of the spatial and contextual disparities of determinant factors of adult obesity among communities in Chicago

The issue of adult obesity has multiple complexes contributing factors and is becoming a significant public health concern worldwide, including in the neighborhoods of Chicago. This study utilized data on nineteen demographic, environmental, socioeconomic, and behavioral characteristics of community neighborhoods in Chicago to analyze the interplay and impact of these complex factors, which is essential for understanding and addressing the issue. The analysis revealed significant geographic variations in the prevalence of adult obesity across Chicago neighborhoods, with associations of these patterns found significant in 17 out of 19 determinant factors studied. Notably, strong associations were found between obesity and the percentage of the White population, the quality of sidewalks and walkability, the economic hardship index, and the unemployment rate. Identifying high-risk adult obesity communities and understanding the multifaceted contributing factors is crucial for developing evidence-based interventions and policy initiatives to reduce obesity and create healthier, more equitable urban neighborhoods for a city such as Chicago and beyond.

60 APPLIED LIFE SCIENCES↗

Distribution of genetic variation underlying adult migration timing in steelhead of the Columbia River basin

Abstract Fish migrations are energetically costly, especially when moving between freshwater and saltwater, but are a viable strategy for Pacific salmon and trout ( Oncorhynchus spp.) due to the advantageous resources available at various life stages. Anadromous steelhead ( O. mykiss ) migrate vast distances and exhibit variation for adult migration phenotypes that have a genetic basis at candidate genes known as greb1L and rock1 . We examined the distribution of genetic variation at 13 candidate markers spanning greb1L , intergenic, and rock1 regions versus 226 neutral markers for 113 populations ( n = 9,471) of steelhead from inland and coastal lineages in the Columbia River. Patterns of population structure with neutral markers reflected genetic similarity by geographic region as demonstrated in previous studies, but candidate markers clustered populations by genetic variation associated with adult migration timing. Mature alleles for late migration had the highest frequency overall in steelhead populations throughout the Columbia River, with only 9 of 113 populations that had a higher frequency of premature alleles for early migration. While a single haplotype block was evident for the coastal lineage, we identified multiple haplotype blocks for the inland lineage. The inland lineage had one haplotype block that corresponded to candidate markers within the greb1L gene and immediately upstream in the intergenic region, and the second block only contained candidate markers from the intergenic region. Haplotype frequencies had similar patterns of geographic distribution as single markers, but there were distinct differences in frequency between the two haplotype blocks for the inland lineage. This may represent multiple recombination events that differed between lineages where phenotypic differences exist between freshwater entry versus arrival timing as indicated by Micheletti et al. (2018a). Redundancy analyses were used to model environmental effects on allelic frequencies of candidate markers, and significant variables were migration distance, temperature, isothermality, and annual precipitation. This study improves our understanding of the spatial distribution of genetic variation underlying adult migration timing in steelhead as well as associated environmental factors and has direct conservation and management implications.

Collins, Erin E.↗

Neuroimaging in adult penetrating brain injury: a guide for radiographers

Penetrating brain injuries (PBI) are a medical emergency, often resulting in complex damage and high mortality rates. Neuroimaging is essential to evaluate the location and extent of injuries, and to manage them accordingly. Currently, a myriad of imaging modalities are included in the diagnostic workup for adult PBI, including skull radiography, computed tomography (CT), magnetic resonance imaging (MRI) and angiography, with each modality providing their own particular benefits. This literature review explores the current modalities available for investigating PBI and aims to assist in decision making for the appropriate use of diagnostic imaging when presented with an adult PBI. Based on the current literature, the authors have developed an imaging pathway for adult penetrating brain injury that functions as both a learning tool and reference guide for radiographers and other health professionals. Currently, CT is recommended as the imaging modality of choice for the initial assessment of PBI patients, while MRI is important in the sub-acute setting where it aids prognosis prediction and rehabilitation planning, Additional follow-up imaging, such as angiography, should be dependent upon clinical findings.

62 RADIOLOGY AND NUCLEAR MEDICINE↗

Validation of Scale-Derived Ages in Wild Juvenile and Adult Steelhead Using Parental-Based Tagging

Abstract Accurate age information is a critical component in fisheries monitoring, management, and research. The ability to assign accurate ages to fish by using nonlethal structures is vital in calculating cohort productivity for fish species with low abundances and variable life histories. A common nonlethal method to assign ages is by interpretation of patterns in scales. Validation of ages is not easily obtained for free-ranging fishes; however, the development of genetic “tags” has expanded age validation opportunities. In this study, we used parental-based genetic tagging to validate ages determined from scales collected from juvenile and adult steelhead Oncorhynchus mykiss in two streams within the Snake River basin. Juvenile scale ages were in agreement with 93% of the known ages. Adult scale ages were in agreement with 89% of the known ages. Although overall bias in juvenile ages was very low, we saw a slight positive bias in younger fish (young of the year and age 1) and a small negative bias in older juveniles (ages 2–4). A small negative bias in ages of adults was a consequence of errors in freshwater age. The errors observed did not significantly bias age compositions because the 90% confidence intervals about the age proportions based on scales contained the known proportions; therefore, scale analysis is an acceptable method for assigning ages to Snake River steelhead. We discuss the value of validated known-age scales as a reference collection, and as an illustrative use, we constructed a circulus count guide to aid technicians in identifying missing annuli and distinguishing true from false annuli. To demonstrate the use of the circulus guidelines, we reanalyzed samples with age discrepancies, applying the circulus count data and the known age to identify mistakes.

Reinhardt, Leslie↗

Wnt3 and Gata4 regulate axon regeneration in adult mouse DRG neurons

Highlights: • Wnt genes have distinct expression patterns in cultured DRG neurons and injured DRGs. • Downregulation or overexpression of Wnt3 promotes or inhibits axon regeneration respectively in adult DRG neurons. • Wnt3 modulates axon regeneration by repressing the gene expression of Gata4. Neurons in the adult central nervous system (CNS) have a poor intrinsic axon growth potential after injury, but the underlying mechanisms are largely unknown. Wingless-related mouse mammary tumor virus integration site (WNT) family members regulate neural stem cell proliferation, axon tract and forebrain development in the nervous system. Here we report that Wnt3 is an important modulator of axon regeneration. Downregulation or overexpression of Wnt3 in adult dorsal root ganglion (DRG) neurons enhances or inhibits their axon regeneration ability respectively in vitro and in vivo. Especially, we show that Wnt3 modulates axon regeneration by repressing mRNA translation of the important transcription factor Gata4 via binding to the three prime untranslated region (3′UTR). Downregulation of Gata4 could restore the phenotype exhibited by Wnt3 downregulation in DRG neurons. Taken together, these data indicate that Wnt3 is a key intrinsic regulator of axon growth ability of the nervous system.

60 APPLIED LIFE SCIENCES↗

Distinct function of miR-17-92 cluster in the dorsal and ventral adult hippocampal neurogenesis

Highlights: • miR-17-92 is highly related with hippocampal neurogenesis and mood behavior. • The expression of miR-17-92 cluster is regionally different in hippocampus. • miR-17-92 KO less affect development of neural progenitors in ventral hippocampus. • Interestingly, memory function was not altered by miR-17-92 KO. • These findings suggest the distinct function of regional expression of miR-17-92. It has been known that the dorsal and ventral areas of the dentate gyrus in the hippocampus have distinct roles in memory and mood behaviors. We previously reported that microRNA miR-17-92 regulates adult hippocampal neurogenesis and mood disorders. Here, we suggest that the miR-17-92 cluster is highly expressed in the ventral than the dorsal dentate gyrus in the adult mouse hippocampus. Deletion of miR-17-92 in the adult hippocampus only affects development of neural progenitors in the ventral dentate gyrus, and miR-17-92 knockout mice have no defects in memory functions. Our results suggest that regional expression of miR-17-92 in the dentate gyrus is associated with their distinct functions in hippocampal neurogenesis and related behaviors.

60 APPLIED LIFE SCIENCES↗

Effects of blood lead levels on airflow limitations in Korean adults: Findings from the 5th KNHNES 2011

This study aimed to examine whether blood levels of heavy metals, such as lead, mercury and cadmium, are related with pulmonary function in Korean adults. This investigation included 870 Korean adults (≥40 years) who received pulmonary function testing in the Korea National Health and Nutrition Examination Survey (KNHANES) V-2, 2011. Data of blood levels of heavy metals, pulmonary function tests and anthropometric measurements were acquired. Blood lead levels showed inverse correlations with the FEV{sub 1}/FVC ratio before (r=−0.276, p<0.001) and after adjustment of multiple compounding factors (r=−0.115, p=0.001). A logistic multiple regression analysis revealed that blood lead levels were a significant influencing factor for the FEV{sub 1}/FVC ratio (β=−0.017, p=0.001, adjusted R{sup 2}=0.267). The odds ratios (ORs) for the FEV{sub 1}/FVC ratio were significantly lower in the highest tertile group of the blood lead levels than in the lowest tertile group in Model 1 (OR=0.007, 95% CI=0.000−0.329) and Model 2 (OR=0.006, 95% CI=0.000−0.286). These findings imply that environmental exposure to lead might be an important factor that may cause airflow limitations in Korean adults. - Highlights: • Blood lead levels showed inverse correlations with the FEV{sub 1}/FVC ratio. • Blood lead level was a significant influencing factor for the FEV{sub 1}/FVC ratio. • ORs for FEV{sub 1}/FVC were lower in the highest blood lead group than in the lowest group. • Environmental exposure to lead might be an important factor for airflow limitations.

54 ENVIRONMENTAL SCIENCES↗

Systemic inflammatory markers associated with cardiovascular disease and acute and chronic exposure to fine particulate matter air pollution (PM2.5) among US NHANES adults with metabolic syndrome

Highlights: • A cross sectional study of the effect of PM{sub 2.5} AP on inflammatory biomarkers among NHANES participants was conducted. • Participants’ Census tract of residence was linked to USEPA downscaler modeled air pollution for the continental US. • Goal was the assessment of susceptibility of adults with metabolic syndrome to PM2.5 exposure and levels of CRP and WBC. • There was a significant effect of PM2.5 at lag day 0; a 10 µg/m3 rise was associated with a 10.1% increase in CRP level. • There were no significant associations with CRP or WBC for those without metabolic syndrome. There has been no investigation to date of adults with metabolic syndrome examining the association of short and long-term exposure to fine particulate matter (PM{sub 2.5}) air pollution with cardiovascular-disease related inflammatory marker (WBC and CRP) levels in a nationally representative sample. The goal of this study is to assess the susceptibility of adults with metabolic syndrome to PM{sub 2.5} exposure as suggested by increased cardiovascular-disease related inflammatory marker levels.

54 ENVIRONMENTAL SCIENCES↗

Endotoxin enhances respiratory effects of phthalates in adults: Results from NHANES 2005-6

Highlights: ●Phthalates are associated with allergy and asthma, but the potential mechanisms are unclear. ●Individuals living in homes with low endotoxin showed no association between phthalates and respiratory outcomes. ●An interaction was present for phthalates and endotoxin for respiratory symptoms of wheeze and asthma, but not rhinitis and hay fever. Phthalates have been associated with respiratory symptoms in adults; they may enhance effects of inflammatory compounds. To assess the potential interactions of phthalates and endotoxin on respiratory and allergic symptoms in adults, we used cross-sectional information from the 1091 adults with complete data on urinary phthalates and house dust endotoxin from NHANES 2005–2006. We used multivariable logistic regression to assess whether endotoxin levels modified the association between nine phthalate metabolites and four current allergic symptoms (asthma, wheeze, hay fever, and rhinitis). Endotoxin was classified into tertiles (>25 EU/mg dust). Urinary phthalate and dust endotoxin levels were not correlated (r < |0.02|). Under low endotoxin conditions, no associations between phthalates and respiratory outcomes were observed. Under medium or high endotoxin conditions, exposure-response relationships were observed between specific phthalates and wheeze and asthma. For wheeze, three phthalates (mono-benzyl phthalate (MBzP), mono(carboxyoctyl) phthalate (MCOP), and di-ethylhexyl phthalate (DEHP) had significant interactions with endotoxin); for asthma, two phthalates (MCOP and mono(carboxyoctyl) phthalate (MCNP)) had significant interactions. Endotoxin did not modify the associations between phthalates and hay fever or rhinitis. These results are consistent with the hypothesis that endotoxin enhances the respiratory toxicity of phthalates; however this cross-sectional study cannot address key temporal issues. The lack of an association between wheeze or asthma and phthalates when endotoxin exposure was low suggests that phthalates alone may not increase these symptoms.

54 ENVIRONMENTAL SCIENCES↗

Absorption of wireless radiation in the child versus adult brain and eye from cell phone conversation or virtual reality

Highlights: • More cell phone radiation is absorbed by children's inner brain tissues than adults’. • Children's radiofrequency radiation exposure should be reduced. • Further research to evaluate the risks to the eye from use of VR is urgently needed. • It is biologically relevant and feasible to reduce the standards’ averaging volume. • Current methods to determine wireless device compliance should be revised. Children's brains are more susceptible to hazardous exposures, and are thought to absorb higher doses of radiation from cell phones in some regions of the brain. Globally the numbers and applications of wireless devices are increasing rapidly, but since 1997 safety testing has relied on a large, homogenous, adult male head phantom to simulate exposures; the “Standard Anthropomorphic Mannequin” (SAM) is used to estimate only whether tissue temperature will be increased by more than 1 Celsius degree in the periphery. The present work employs anatomically based modeling currently used to set standards for surgical and medical devices, that incorporates heterogeneous characteristics of age and anatomy. Modeling of a cell phone held to the ear, or of virtual reality devices in front of the eyes, reveals that young eyes and brains absorb substantially higher local radiation doses than adults’. Age-specific simulations indicate the need to apply refined methods for regulatory compliance testing; and for public education regarding manufacturers' advice to keep phones off the body, and prudent use to limit exposures, particularly to protect the young.

54 ENVIRONMENTAL SCIENCES↗

In Vivo Brain Plaque and Tangle Burden Mediates the Association Between Diastolic Blood Pressure and Cognitive Functioning in Nondemented Adults

OBJECTIVE Growing evidence supports an association among increased blood pressure and: (a) poor cognitive performance in older adults, and (b) various biomarkers of increased Alzheimer's disease (AD) neuropathology. The objective of this study was to determine whether systolic blood pressure (SBP) and diastolic blood pressure (DBP) were significantly associated with cognitive functioning in non-demented adults, and to examine in vivo AD pathology as a possible mediator of this association. METHODS Positron emission tomography (PET) scans with 2-(1-{6-[(2-[F-18]fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene)malononitrile (FDDNP) provide in vivo measurements of plaque and tangle burden. A total of 101 non-demented older subjects with blood pressure data and FDDNP-PET scans were drawn from a larger study of predictors of cognitive decline. A neuropsychological test battery was used to compute "global cognitive scores" (averaged across five key domains), which served as an index of general cognitive functioning. RESULTS Higher DBP (but not SBP) was significantly associated with lower cognitive scores, controlling for age, sex, antihypertensive medication use, and ApoE genotype (η2 = 0.06). However, this relationship was no longer significant after introducing FDDNP-PET binding as an additional covariate in the statistical models. In vivo plaque and tangle burden accounted for over 30% of the observed association between higher DBP and poorer cognitive performance. CONCLUSIONS By indicating a mediation of the relationship between DBP and cognitive functioning by FDDNP-PET binding, this study advances our understanding of some potential predictors of cognitive decline in non-demented adults, and underscores the importance of devising early multimodal interventions to more effectively combat degenerative brain disorders.

60 APPLIED LIFE SCIENCES↗

Age-dependent behaviors, seizure severity and neuronal damage in response to nerve agents or the organophosphate DFP in immature and adult rats

Exposure to nerve agents (NAs) and other organophosphates (OPs) can initiate seizures that rapidly progress to status epilepticus (SE). While the electrographic and neuropathological sequelae of SE evoked by NAs and OPs have been characterized in adult rodents, they have not been adequately investigated in immature animals. In this study postnatal day (PND) 14, 21 and 28 rat pups, along with PND70 animals as adult controls, were exposed to NAs (sarin, VX) or another OP (diisopropylfluorophosphate, DFP). We then evaluated behavioral and electrographic (EEG) correlates of seizure activity, and performed neuropathology using Fluoro-Jade B. Although all immature rats exhibited behaviors that are often characterized as seizures, the incidence, duration, and severity of the electrographic seizure activity were age-dependent. No (sarin and VX) or brief (DFP) EEG seizure activity was evoked in PND14 rats, while SE progressively increased in severity as a function of age in PND21, 28 and 70 animals. Fluoro-Jade B staining was observed in multiple brain regions of animals that exhibited prolonged seizure activity. Neuronal injury in PND14 animals treated with DFP was lower than in older animals and absent in rats exposed to sarin or VX. In conclusion, we found that NAs and an OP provoked robust SE and neuronal injury similar to adults in PND21 and PND28, but not in PND14, rat pups. Convulsive behaviors were often present independent of EEG seizures and were unaccompanied by neuronal damage. These differential responses should be considered when investigating medical countermeasures for NA and OP exposure in pediatric populations.

Neurosciences & Neurology↗

The proteasome inhibitor bortezomib induces testicular toxicity by upregulation of oxidative stress, AMP-activated protein kinase (AMPK) activation and deregulation of germ cell development in adult murine testis

Understanding how chemotherapeutic agents mediate testicular toxicity is crucial in light of compelling evidence that male infertility, one of the severe late side effects of intensive cancer treatment, occurs more often than they are expected to. Previous study demonstrated that bortezomib (BTZ), a 26S proteasome inhibitor used to treat refractory multiple myeloma (MM), exerts deleterious impacts on spermatogenesis in pubertal mice via unknown mechanisms. Here, we showed that intermittent treatment with BTZ resulted in fertility impairment in adult mice, evidenced by testicular atrophy, desquamation of immature germ cells and reduced caudal sperm storage. These deleterious effects may originate from the elevated apoptosis in distinct germ cells during the acute phase and the subsequent disruption of Sertoli–germ cell anchoring junctions (AJs) during the late recovery. Mechanistically, balance between AMP-activated protein kinase (AMPK) activation and Akt/ERK pathway appeared to be indispensable for AJ integrity during the late testicular recovery. Of particular interest, the upregulated testicular apoptosis and the following disturbance of Sertoli–germ cell interaction may both stem from the excessive oxidative stress elicited by BTZ exposure. We also provided the in vitro evidence that AMPK-dependent mechanisms counteract follicle-stimulating hormone (FSH) proliferative effects in BTZ-exposed Sertoli cells. Collectively, BTZ appeared to efficiently prevent germ cells from normal development via multiple mechanisms in adult mice. Employment of antioxidants and/or AMPK inhibitor may represent an attractive strategy of fertility preservation in male MM patients exposed to conventional BTZ therapy and warrants further investigation. - Highlights: • Intermittent treatment with BTZ caused fertility impairment in adult mice. • BTZ treatment elicited apoptosis during early phase of testicular recovery. • Up-regulation of oxidative stress by BTZ treatment disrupted AJs dynamics. • BTZ treatment stimulated AMPK activity during late phase of testicular recovery. • AMPK-dependent mechanisms counteract FSH proliferative effects in BTZ-exposed SCs.

60 APPLIED LIFE SCIENCES↗

Differentiation in stem/progenitor cells along fetal or adult hepatic stages requires transcriptional regulators independently of oscillations in microRNA expression

Highlights: • The role of microRNAs in differentiation of stem cells is not well understood. • This study found microRNA levels oscillated during differentiation of hepatocytes. • Many functions but not differentiation were regulated by microRNAs in hepatocytes. • Regulators of gene networks independently maintained hepatic differentiation. • These insights will advance how stem cells may contribute in disease mechanisms and therapies. Understanding mechanisms in lineage differentiation is critical for organ development, pathophysiology and oncogenesis. To determine whether microRNAs (miRNA) may serve as drivers or adjuncts in hepatic differentiation, we studied human embryonic stem cell-derived hepatocytes and primary hepatocytes representing fetal or adult stages. Model systems were used for hepatic lineage advancement or regression under culture conditions with molecular assays. Profiles of miRNA in primary fetal and adult hepatocytes shared similarities and distinctions from pluripotent stem cells or stem cell-derived early fetal-like hepatocytes. During phenotypic regression in fetal or adult hepatocytes, miRNA profiles oscillated to regain stemness-associated features that had not been extinguished in stem cell-derived fetal-like hepatocytes. These oscillations in stemness-associated features were not altered in fetal-like hepatocytes by inhibitory mimics for dominantly-expressed miRNA, such as hsa-miR-99b, -100, -214 and -221/222. The stem cell-derived fetal-like hepatocytes were permissive for miRNA characterizing mature hepatocytes, including mimics for hsa-miR-122, -126, -192, -194 and -26b, although transfections of the latter did not advance hepatic differentiation. Examination of genome-wide mRNA expression profiles in stem cell-derived or primary fetal hepatocytes indicated targets of highly abundant miRNA regulated general processes, e.g., cell survival, growth and proliferation, functional maintenance, etc., without directing cell differentiation. Among upstream regulators of gene networks in stem cell-derived hepatocytes included HNF4A, SNAI1, and others, which affect transcriptional circuits directing lineage development or maintenance. Therefore, miRNA expression oscillated in response to microenvironmental conditions, whereas lineage-specific transcriptional regulators, such as HNF4A, were necessary for directing hepatic differentiation. This knowledge will be helpful for understanding the contribution of stem cells in pathophysiological states and oncogenesis, as well as for applications of stem cell-derived hepatocytes.

60 APPLIED LIFE SCIENCES↗

Long-term survival and second malignant tumor prediction in pediatric, adolescent, and young adult cancer survivors using Random Survival Forests: a SEER analysis

Abstract Survival and second malignancy prediction models can aid clinical decision making. Most commonly, survival analysis studies are performed using traditional proportional hazards models, which require strong assumptions and can lead to biased estimates if violated. Therefore, this study aims to implement an alternative, machine learning (ML) model for survival analysis: Random Survival Forest (RSF). In this study, RSFs were built using the U.S. Surveillance Epidemiology and End Results to (1) predict 30-year survival in pediatric, adolescent, and young adult cancer survivors; and (2) predict risk and site of a second tumor within 30 years of the first tumor diagnosis in these age groups. The final RSF model for pediatric, adolescent, and young adult survival has an average Concordance index (C-index) of 92.9%, 94.2%, and 94.4% and average time-dependent area under the receiver operating characteristic curve (AUC) at 30-years since first diagnosis of 90.8%, 93.6%, 96.1% respectively. The final RSF model for pediatric, adolescent, and young adult second malignancy has an average C-index of 86.8%, 85.2%, and 88.6% and average time-dependent AUC at 30-years since first diagnosis of 76.5%, 88.1%, and 99.0% respectively. This study suggests the robustness and potential clinical value of ML models to alleviate physician burden by quickly identifying highest risk individuals.

60 APPLIED LIFE SCIENCES↗

Comparison of Electronarcosis and Carbon Dioxide Sedation Effects on Travel Time in Adult Chinook and Coho Salmon

Abstract The immobilization of fish during handling is crucial in avoiding injury to fish and is thought to reduce handling stress. Chemical sedatives have been a primary choice for fish immobilization. However, most chemical sedatives accumulate in tissues, and often food fishes must be held until accumulations degrade to levels safe for human consumption. Historically, there have been few options for nonchemical sedation. Carbon dioxide (CO2) has been widely used for decades as a sedative, and while it does not require a degradation period, it does have drawbacks. The use of electronarcosis is another nonchemical option that does not require degradation time. However, little is known about the latent and delayed effects on migration rates of adult salmonids that have been immobilized with electricity. We compared the travel times of adult Chinook Salmon Oncorhynchus tshawytscha and Coho Salmon O. kisutch through a fishway at river kilometer (rkm) 4, and to rkm 16 and rkm 32 after being immobilized with either CO2 or electronarcosis. Travel times of fish treated with either CO2 or electronarcosis were similar within species. Because of the nearly instantaneous induction of and recovery from electronarcosis, we recommend it as an alternative to CO2 for handling large adult salmonids. Received February 17, 2015; accepted June 27, 2015

Keep, Shane G.↗