Publications by authors named "Akins J"

Article Synopsis
  • Wolverines in North America have seen a reduction in their distribution due to human activities during the 19th and 20th centuries, leading to their threatened status in the US and special concern status in Canada.
  • A study collected 882 genetic samples to analyze landscape connectivity factors, focusing on terrain complexity, human disturbance, forest configuration, and climate across a vast region of southwestern Canada and northwestern US.
  • Findings showed that human disturbance negatively affects wolverine genetic connectivity, while forest cover and snow persistence help maintain genetic diversity, which can inform future conservation management efforts.
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Background: Successful ovulation is essential for natural conception and fertility. Defects in the ovulatory process are associated with various conditions of infertility or subfertility in women. However, our understanding of the intra-ovarian biochemical mechanisms underlying this process in women has lagged compared to our understanding of animal models.

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  • * Using a large dataset from camera traps across 17 countries, the researchers applied mixed-effects models to analyze the probability of these animals being detected in groups, revealing significant variability in group formation even among species traditionally thought to be solitary.
  • * The findings suggest that resource distribution (like patchiness) and external conditions (such as winter severity) influence whether these animals aggregate, underscoring the need to better understand the complexities of social behavior in solitary species for a comprehensive view of their ecology and social interactions.
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Background: We tested the hypothesis that patients with heart failure with preserved ejection fraction (HFpEF) would have greater muscle sympathetic nerve activity (MSNA) at rest and sympathetic reactivity during a cold pressor test compared with non-heart failure controls. Further, given the importance of the baroreflex modulation of MSNA in the control of blood pressure (BP), we hypothesized that patients with HFpEF would exhibit a reduced sympathetic baroreflex sensitivity.

Methods: Twenty-eight patients with HFpEF and 44 matched controls (mean±SD: 71±8 versus 70±7 years; 9 men/19 women versus 16 men/28 women) were studied.

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Carnivores play critical roles in ecosystems, yet many species are declining worldwide. The Sierra Nevada Red Fox (; SNRF) is a rare and endangered subspecies of red fox limited to upper montane forests, subalpine, and alpine environments of California and Oregon, United States. Having experienced significant distribution contractions and population declines in the last century, the subspecies is listed as at-risk by relevant federal and state agencies.

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Introduction: The vaping epidemic in the US has been largely attributed to the emergence of pod-based e-cigarette devices. While these devices continue to be promoted as alternatives to cigarettes, their impact on cardiovascular and behavioral outcomes remains incompletely understood. This study assessed the impact of pod-based e-cigarettes on peripheral and cerebral vascular function, along with subjective experiences among adult cigarette smokers.

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Excessive sympathetic activity during exercise causes heightened peripheral vasoconstriction, which can reduce oxygen delivery to active muscles, resulting in exercise intolerance. Although both patients suffering from heart failure with preserved and reduced ejection fraction (HFpEF and HFrEF, respectively) exhibit reduced exercise capacity, accumulating evidence suggests that the underlying pathophysiology may be different between these two conditions. Unlike HFrEF, which is characterized by cardiac dysfunction with lower peak oxygen uptake, exercise intolerance in HFpEF appears to be predominantly attributed to peripheral limitations involving inadequate vasoconstriction rather than cardiac limitations.

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The incidence of syncope during orthostasis increases in early human pregnancy, which may be associated with cerebral blood flow (CBF) dysregulation in the upright posture. In addition, obesity and/or sleep apnea per se may influence CBF regulation due to their detrimental impacts on cerebrovascular function. However, it is unknown whether early pregnant women with obesity and/or sleep apnea could have impaired CBF regulation in the supine position and whether this impairment would be further exacerbated in the upright posture.

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Article Synopsis
  • A study on older adults (aged 60-83) examined the effects of a cold pressor test on muscle sympathetic nerve activity (MSNA), revealing that older women showed varied responses compared to men with different baseline MSNA levels.* -
  • Results showed that women with higher baseline MSNA had a significantly lower increase in MSNA during the cold pressor test compared to those with lower baseline MSNA, while men showed no such difference.* -
  • The findings suggest that higher baseline sympathetic activity in older women may dampen MSNA responses during stress tests without affecting changes in blood pressure or heart rate, indicating complex mechanisms at play.*
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Sympathetic activation is a hallmark of pregnancy. However, longitudinal assessments of muscle sympathetic nerve activity (MSNA) in pregnancy are scarce and have primarily focused on burst occurrence (frequency) at rest, despite burst strength (amplitude) representing distinct characteristics of sympathetic outflow. Thus, we assessed MSNA burst amplitude distributions in healthy women to determine the impact of normal pregnancy on neural discharge patterns in response to orthostatic stress.

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Purpose: The objective of this investigation was to compare the acute hemodynamic responses during single-leg knee extension (SLKE) exercise between female breast cancer (BC) survivors previously treated with anthracycline chemotherapy and age- and sex-matched control (CON) subjects.

Methods: Fourteen BC survivors (age: 61 ± 7 yr; time post-anthracycline therapy: 12 ± 6 yr) and nine CON subjects (age: 59 ± 7 yr) performed SLKE exercise at 25%, 50%, and 75% of peak power output during which heart rate, blood pressure (BP), leg blood flow (Doppler ultrasonography), and vascular conductance (leg blood flow/mean BP) were measured. Quadriceps mass was estimated from thigh volume and skinfold measures.

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Background: Mental health care disparities are persistent and have increased in recent years. Compared with their White counterparts, members of racially and ethnically minoritized groups have less access to mental health care. Minoritized groups also have lower engagement in mental health treatment and are more likely to experience ineffective patient-provider communication, which contribute to negative mental health care experiences and poor mental health outcomes.

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The objective of this study was to examine long-term trends in serum cotinine (COT) concentrations, as a measure of secondhand smoke (SHS) exposure, in U.S. nonsmokers using data from the National Health and Nutrition Examination Surveys (NHANES) from 2003 to 2018.

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African-American (AA) individuals are disproportionately affected by cardiovascular diseases. Plant-based diets (PBD) may be cardioprotective in part through their high antioxidant capacity and low inflammatory load. We tested the hypothesis that AA individuals adhering to a 100% PBD would have better vascular health than AA individuals following a typical American diet (TAD).

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Article Synopsis
  • The study examines whether vascular function differs between young non-Hispanic Black men and women, focusing on peripheral and cerebral responses.
  • Findings reveal that non-Hispanic Black women have better peripheral conduit artery and cerebrovascular responses, although microvascular function is similar to men.
  • This suggests that differences in vascular function may contribute to unique cardiovascular and cerebrovascular disease patterns observed between sexes in the non-Hispanic Black population.*
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As anthropogenic disturbances continue to drive habitat loss and range contractions, the maintenance of evolutionary processes will increasingly require targeting measures to the population level, even for common and widespread species. Doing so requires detailed knowledge of population genetic structure, both to identify populations of conservation need and value, as well as to evaluate suitability of potential donor populations. We conducted a range-wide analysis of the genetic structure of red foxes in the contiguous western U.

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Non-Hispanic black (BL) individuals have the greatest prevalence of cardiovascular disease (CVD), relative to other racial/ethnic groups (e.g., non-Hispanic white population; WH), which may be secondary to blunted vascular function.

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Introduction: The Population Assessment of Tobacco and Health (PATH) Study is a nationally representative cohort of tobacco product users and nonusers. The study's main purpose is to obtain longitudinal epidemiologic data on tobacco use and exposure among the US population.

Aims And Methods: Nicotine biomarkers-cotinine (COT) and trans-3'-hydroxycotinine (HCT)-were measured in blood samples collected from adult daily tobacco users and nonusers during Wave 1 of the PATH Study (2013-2014; n = 5012; one sample per participant).

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High altitude-induced hypoxaemia is often associated with peripheral vascular dysfunction. However, the basic mechanism(s) underlying high-altitude vascular impairments remains unclear. This study tested the hypothesis that oxidative stress contributes to the impairments in endothelial function during early acclimatization to high altitude.

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Background: In middle-aged adults with depression, cerebral vasodilatory reactivity is blunted; however, this has not been examined in treatment-naïve young adults with major depressive disorder (MDD). We tested the hypothesis that cerebrovascular reactivity would be blunted in young adults (18-30 yrs) with MDD compared to healthy non-depressed adults (HA) and would be attenuated to a greater extent in adults with symptomatic MDD (sMDD) compared to adults with MDD in remission (euthymic MDD; eMDD).

Methods: Sixteen adults with MDD [21±3yrs; n = 8 sMDD (6 women); n = 8 eMDD (5 women)] and 14 HA (22±3yrs; 9 women) participated.

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Background: Increasing iron bioavailability attenuates hypoxic pulmonary vasoconstriction in both lowlanders and Sherpas at high altitude. In contrast, the pulmonary vasculature of Andean individuals with chronic mountain sickness (CMS) is resistant to iron administration. Although pulmonary vascular remodeling and hypertension are characteristic features of CMS, the effect of iron administration in healthy Andean individuals, to our knowledge, has not been investigated.

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Near-infrared diffuse correlation spectroscopy (NIR-DCS) is an optical technique for estimating relative changes in skeletal muscle perfusion during exercise but may be affected by changes in cutaneous blood flow, as photons emitted by the laser must first pass through the skin. Accordingly, the purpose of this investigation was to examine how increased cutaneous blood flow affects NIR-DCS blood flow index (BFI) at rest and during exercise using a passive whole body heating protocol that increases cutaneous, but not skeletal muscle, perfusion in the uncovered limb. BFI and cutaneous perfusion (laser-Doppler flowmetry) were assessed in 15 healthy young subjects before (e.

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