7 research outputs found
Identification of Putative Origins of Introduced Pigs in Indiana Using Nuclear Microsatellite Markers and Oral History
Feral swine (Sus scrofa) have been introduced throughout North America from various global locations (Mayer and Brisbin 1991). In some cases, sources for feral swine are provided through historical records, but for many newly established populations, the origins of feral swine are not known. Understanding the origins and dispersal patterns of feral swine is an important management consideration, because of the introduction of diseases to new locations, for prosecution of individuals who have trans-ported feral swine across state lines, and for allocating swine removal efforts appropriately to address swine translocations within a state or a management area
Metformin improves diastolic function in an HFpEF-like mouse model by increasing titin compliance
Heart failure with preserved ejection fraction (HFpEF) is a complex syndrome characterized by a preserved ejection fraction but increased diastolic stiffness and abnormalities of filling. Although the prevalence of HFpEF is high and continues to rise, no effective therapies exist; however, the diabetic drug metformin has been associated with improved diastolic function in diabetic patients. Here we determine the therapeutic potential of metformin for improving diastolic function in a mouse model with HFpEF-like symptoms. We combine transverse aortic constriction (TAC) surgery with deoxycorticosterone acetate (DOCA) supplementation to obtain a mouse model with increased diastolic stiffness and exercise intolerance. Echocardiography and pressure-volume analysis reveal that providing metformin to TAC/DOCA mice improves diastolic function in the left ventricular (LV) chamber. Muscle mechanics show that metformin lowers passive stiffness of the LV wall muscle. Concomitant with this improvement in diastolic function, metformin-treated TAC/DOCA mice also demonstrate preserved exercise capacity. No metformin effects are seen in sham operated mice. Extraction experiments on skinned ventricular muscle strips show that the metformin-induced reduction of passive stiffness in TAC/DOCA mice is due to an increase in titin compliance. Using phospho-site-specific antibodies, we assay the phosphorylation of titin's PEVK and N2B spring elements. Metformin-treated mice have unaltered PEVK phosphorylation but increased phosphorylation of PKA sites in the N2B element, a change which has previously been shown to tower titin's stiffness. Consistent with this result, experiments with a mouse model deficient in the N2B element reveal that the beneficial effect of metformin on LV chamber and muscle stiffness requires the presence of the N2B element. We conclude that metformin offers therapeutic benefit during HFpEF by lowering titin-based passive stiffness.National Institutes of Health [HL062881, HL118524]; Fondation Leducq [TNE-13CVD04]; European Research Council [StG282078, T32GM084905]This item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]
Molecular Population Structure for Feral Swine in the United States
Feral swine (Sus scrofa) have invaded most of the United States and continue to expand throughout North America. Given the ecological and economic threats posed by increasing feral swine abundance, it is imperative to develop an understanding of their patterns of natural range expansion and human-mediated introductions. Towards this goal, we used molecular markers to elucidate the genetic structure of feral swine populations throughout the United States and evaluated the association between historical introductions and contemporary patterns of genetic organization. We used STRUCTURE and discriminant analysis of principal components (DAPC) to delineate genetic clusters for 959 individuals genotyped at 88 single nucleotide polymorphism loci. We identified 10 and 12 genetic clusters for the 2 clustering approaches, respectively. We observed strong agreement in clusters across approaches, with both describing clusters having strong geographic association at regional levels reflecting past introduction and range expansion patterns. In addition, we evaluated patterns of isolation by distance to test for and estimate spatial scaling of population structure within western, central, and eastern regions of North America. We found contrasting spatial patterns of genetic relatedness among regions, suggesting differences in the invasion process, likely as a result of regional variation in landscape heterogeneity and the influence of human mediated introductions. Our results indicate that molecular analyses of population genetic structure can provide reliable insights into the invasion processes of feral swine, thus providing a useful basis for management focused on minimizing continued range expansion by this problematic species
Thermal sensitivity as a measure of spontaneous morphine withdrawal in mice
INTRODUCTION: Opioid withdrawal syndrome is a critical component of opioid abuse and consists of a wide array of symptoms including increases in pain sensitivity (hyperalgesia). A reliable preclinical model of hyperalgesia during opioid withdrawal is needed to evaluate possible interventions to alleviate withdrawal. The following study describes a method for assessing increases in thermal sensitivity on the hotplate in a mouse model of spontaneous morphine withdrawal. METHODS: C57BL/6J mice received 5.5 days of 30, 56, or 100 mg/kg morphine or saline (s.c., twice daily). In Experiment I, thermal sensitivity data were collected at baseline and at 8, 24, 32, 48 hrs and 1 week following the final injection. Thermal sensitivity was assessed by examining latency to respond on a hotplate across a range of temperatures (50, 52, 54, and 56°C). In Experiment II, 0.01 mg/kg buprenorphine was administered 30 min prior to each testing session during the withdrawal period. In Experiment III, jumping during a 30 min period was assessed at baseline and at 0, 8, 24, 32, and 48 hrs following the final morphine injection. RESULTS: During the withdrawal period, thermal sensitivity increased significantly in all morphine-treated mice as compared to saline-treated mice. Thermal sensitivity was greater in mice treated with 56 mg/kg morphine compared to 30 mg/kg and peaked earlier than in mice treated with 100 mg/kg (32 hrs v 1 wk). The increase in thermal sensitivity following 56 mg/kg morphine was attenuated by a dose of buprenorphine that did not produce antinociception alone (i.e., 0.01 mg/kg). In general, the results of the jumping experiment paralleled those obtained in Experiment I. DISCUSSION: Response latency on the hotplate is a reliable and sensitive measure of spontaneous morphine withdrawal in mice, making it an ideal behavior for assessing the potential of medications and environmental interventions to alleviate opioid withdrawal
Reproductive parameters of the fisher (Pekania pennanti) in the southern Sierra Nevada, California
© Published by Oxford University Press on behalf of American Society of Mammalogists 2018. Quantifying reproductive parameters is essential for developing effective conservation plans for species of concern; however, studying reproduction in wild settings can be challenging and local data are frequently unavailable. The fisher (Pekania pennanti) is an elusive forest-dwelling carnivore of conservation concern that occurs across much of boreal North America and reaches the southernmost limit of its distribution in the southern Sierra Nevada (SSN) in California. Data on fisher reproduction in this region are limited and applicability of parameters from other areas is uncertain. To clarify how fisher populations in the SSN compare with those elsewhere in North America, we conducted a comprehensive review of available literature on reproduction throughout the species' range in North America. We then compared findings from the review with data we collected during 7 years in the SSN, focusing on the proportion of females reproducing, litter size, and the parturition date. On average across the fisher's range, the proportion of adult females that reproduced was 0.71 (range: 0.40-1.00; n = 16 studies), litter size was 2.5 (range: 1-4; n = 16 studies), and parturition occurred on 25 March (range: 3 March-17 April; n = 16 studies). In our study area, we tracked 42 adult female fishers, 35 of which reproduced and used 257 reproductive dens (74 natal, 175 maternal, 8 early failures); 0.86 of our females attempted denning (range: 0.79-1.0; n = 93 opportunities) and 0.75 were successful (range: 0.64-1.0; n = 91 opportunities monitored through the den season). Mean litter size was 1.57 (range: 1-3; n = 75 litters) and mean parturition date was 30 March (range: 17 March-12 April; n = 69 natal dens initiated). Female fishers at the southern limit of their distribution in the SSN reproduced at a rate comparable to or higher than elsewhere in North America, but average litter size was the lowest reported for the species. Female fishers in the SSN gave birth at similar or later dates than elsewhere in their range. We explore factors that might explain patterns of variation in fisher reproductive parameters and discuss conservation implications of our findings
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Coronary Artery Calcification (CAC) and PostâTrial Cardiovascular Events and Mortality Within the Women's Health Initiative (WHI) EstrogenâAlone Trial
Background: Among women aged 50 to 59 years at baseline in the Women's Health Initiative (WHI) EstrogenâAlone (EâAlone) trial, randomization to conjugated equine estrogenâalone versus placebo was associated with lower risk of myocardial infarction and mortality, and, in an ancillary study, the WHIâCACS (WHI Coronary Artery Calcification Study) with lower CAC, measured by cardiac computed tomography â8.7 years after baseline randomization. We hypothesized that higher CAC would be related to postâtrial coronary heart disease (CHD), cardiovascular disease (CVD), and total mortality, independent of baseline randomization or risk factors. Methods and Results: WHIâCACS participants (n=1020) were followed â8 years from computed tomography scan in 2005 (mean age=64.4) through 2013 for incident CHD (myocardial infarction and fatal CHD, n=17), CVD (n=69), and total mortality (n=55). Incident CHD and CVD analyses excluded women with CVD before scan (n=89). Women with CAC=0 (n=54%) had very low ageâadjusted rates/1000 personâyears of CHD (0.91), CVD (5.56), and mortality (3.45). In comparison, rates were â2âfold higher for women with any CAC (>0). Associations were not modified by baseline randomization to conjugated equine estrogenâalone versus placebo. Adjusted for baseline randomization and risk factors, the hazard ratio (95% confidence interval) for CAC >100 (19%) was 4.06 (2.11, 7.80) for CVD and 2.70 (1.26, 5.79) for mortality. Conclusions: Among a subset of postmenopausal women aged 50 to 59 years at baseline in the WHI EâAlone Trial, CAC at mean age of 64 years was strongly related to incident CHD, CVD, and to total mortality over â8 years, independent of baseline randomization to conjugated equine estrogenâalone versus placebo or CVD risk factors. Clinical Trial Registration URL: https://www.clinicaltrials.gov. Unique identifier: NCT00000611