Publications by authors named "Charlotte W Usselman"

Polycystic ovary syndrome (PCOS) predisposes women to cardiovascular diseases. Blood pressure (BP) responses to the cold pressor test (CPT) predict future cardiovascular risk but have yet to be characterized in PCOS. Therefore, we compared BP responses to the CPT between females with PCOS (n=10; age: 22±3yr, body mass index (BMI): 23.

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Due to perceived methodological complications, scientific studies have often excluded females. As a result, male-based findings have been generalized to females, despite physiological and biological differences between sexes. Gender has been even less considered in the literature, with little exploration specifically beyond traditional man/woman representation.

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Preeclampsia is a risk factor for future cardiovascular diseases. However, the mechanisms underlying this association remain unclear, limiting effective prevention strategies. Blood pressure responses to acute stimuli may reveal cardiovascular dysfunction not apparent at rest, identifying individuals at elevated cardiovascular risk.

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Discharge of postganglionic muscle sympathetic nerve activity (MSNA) is related poorly to blood pressure (BP) in adults. Whether neural measurements beyond the prevailing level of MSNA can account for interindividual differences in BP remains unclear. The current study sought to evaluate the relative contributions of sympathetic-BP transduction and sympathetic baroreflex gain on resting BP in young adults.

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Recent studies have demonstrated that muscle sympathetic nerve activity (MSNA) responses to isometric exercise differs between active and inactive limbs. Whether limb-dependent responses are characteristic of responses to the cold pressor test (CPT) remains to be established. Therefore, we tested the hypothesis that CPT-induced MSNA responses differ between affected and unaffected limbs such that MSNA in the affected lower limb is greater than MSNA responses in the contralateral lower limb and the upper limb.

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There have been ongoing efforts by federal agencies and scientific communities since the early 1990s to incorporate sex and/or gender in all aspects of cardiovascular research. Scientific journals provide a critical function as change agents to influence transformation by encouraging submissions for topic areas, and by setting standards and expectations for articles submitted to the journal. As part of ongoing efforts to advance sex and gender in cardiovascular physiology research, the recently launched a call for papers on Considering Sex as a Biological Variable.

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In cardiovascular research, sex and gender have not typically been considered in research design and reporting until recently. This has resulted in clinical research findings from which not only all women, but also gender-diverse individuals have been excluded. The resulting dearth of data has led to a lack of sex- and gender-specific clinical guidelines and raises serious questions about evidence-based care.

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Article Synopsis
  • Polycystic ovary syndrome (PCOS) is a complex condition that affects women's reproductive health, metabolism, and increases their risk for cardiovascular diseases.
  • Research indicates that women with PCOS have higher muscle sympathetic nerve activity (MSNA), which is linked to cardiovascular health, with possible variations in its association with androgens based on body weight.
  • The sympathetic nervous system's role in this context suggests it could be targeted for new treatments to reduce cardiovascular risk in women with PCOS, and further studies are encouraged to explore this connection.
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Previously, we demonstrated that integrated muscle sympathetic nerve activity (MSNA) responses to acute chemoreflex stress were augmented during the early follicular (EF) phase of the menstrual cycle relative to both the midluteal (ML) phase and males. These differences were most pronounced in the amplitude component of MSNA, suggesting EF-driven increases in action potential (AP) recruitment in females. Therefore, we tested the hypothesis that neural recruitment, quantified as MSNA AP discharge patterns during acute chemoreflex stress, is potentiated during EF.

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Introduction: Polycystic ovary syndrome (PCOS) is a common endocrinopathy associated with cardiometabolic dysfunction.

Purpose: (1) To compare HRPF indices, including cardiorespiratory fitness (CRF), muscle strength, and muscle endurance, between women with and without PCOS (i.e.

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Polycystic ovary syndrome (PCOS) is associated with endothelial dysfunction; whether this is attributable to comorbid hyperandrogenism and/or obesity remains to be established. Therefore, we ) compared endothelial function between lean and overweight/obese (OW/OB) women with and without androgen excess (AE)-PCOS and ) examined androgens as potential modulators of endothelial function in these women. The flow-mediated dilation (FMD) test was applied in 14 women with AE-PCOS (lean: = 7; OW/OB: = 7) and 14 controls (CTRL; lean: = 7, OW/OB: = 7) at baseline (BSL) and following 7 days of ethinyl estradiol supplementation (EE; 30 µg/day) to assess the effect of a vasodilatory therapeutic on endothelial function; at each time point we assessed peak increases in diameter during reactive hyperemia (%FMD), shear rate, and low flow-mediated constriction (%LFMC).

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Introduction: The prevalence of hypertension is greater in postmenopausal females compared with males of similar age. Previous meta-analyses of normotensive and hypertensive adults have shown that aerobic exercise training reduces systolic blood pressure (SBP) and/or diastolic blood pressure (DBP). However, the effect of aerobic exercise training on blood pressure specifically within healthy postmenopausal females remains unclear.

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Even in the 21st century, female participants continue to be underrepresented in human physiology research. This underrepresentation is attributable in part to the perception that the inclusion of females is more time consuming, less convenient, and more expensive relative to males because of the need to account for the menstrual cycle in cardiovascular study designs. Accounting for menstrual cycle-induced fluctuations in gonadal hormones is important, given established roles in governing vascular function and evidence that failure to consider gonadal hormone fluctuations can result in misinterpretations of biomarkers of cardiovascular disease.

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Muscle sympathetic nerve activity (MSNA) affects vascular resistance differently in women and men. However, whether this sex difference persists during pronounced increases in MSNA remains unclear. Therefore, the purpose of this study was to examine sex differences in neurovascular transduction during cold pressor test (CPT)-mediated sympathoexcitation.

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To determine whether increased chemoreflex tonic activity is associated with augmented muscle sympathetic nervous system activity (MSNA) in women diagnosed with preeclampsia. Women with preeclampsia ( = 19; 32 ± 5 yr old, 31 ± 3 wk of gestation) were matched by age and gestational age with pregnant women (controls, = 38, 32 ± 4 yr old, 31 ± 4 wk gestation; 2:1 ratio). MSNA ( = 9 preeclampsia) was assessed during baseline, peripheral chemoreflex deactivation (hyperoxia), and a cold pressor test (CPT).

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It has been suggested that sex differences in acute blood pressure fluctuations occur during the periods of time between bursts of muscle sympathetic nerve activity. Therefore, we tested the hypothesis that men experience more dynamic changes in mean arterial pressure (Finometer MIDI) than women during acute sympathoinhibition (i.e.

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Introduction: Gestational diabetes mellitus (GDM) is associated with vascular dysfunction. Sympathetic nervous system activity (SNA) is an important regulator of vascular function, and is influenced by glucose and insulin. The association between GDM and SNA (re)activity is unknown.

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Key Points: Emission patterns in muscle sympathetic nerve activity stem from differently sized action potential (AP) subpopulations that express varying discharge probabilities. The mechanisms governing these firing behaviours are unclear. This study investigated the hypothesis that the arterial baroreflex exerts varying control over the different AP subpopulations.

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Preeclampsia is associated with the development of cardiovascular diseases later in life. To investigate this phenomenon, we compared established markers of cardiovascular dysregulation between previously preeclamptic women (PPE; = 12, 13 ± 6 mo postpartum, 34 ± 6 yr) and women who had previously had an uncomplicated pregnancy [control (CTRL); = 12, 15 ± 4 mo postpartum; 29 ± 3 yr]. We hypothesized that PPE would present with elevated arterial stiffness (assessed as central and peripheral pulse wave velocity) and muscle sympathetic nerve activity (MSNA; microneurography) and blunted baroreflex sensitivity (BRS) relative to CTRL.

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Slow breathing (SLOWB) is recommended for use as an adjuvant treatment for hypertension. However, the extent to which blood pressure (BP) responses to SLOWB differ between men and women are not well-established. Therefore, we tested the hypothesis that an acute bout of SLOWB would induce larger decreases in BP in males than in females, given that males typically have higher resting BP.

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Key Points: Normotensive pregnancy is associated with elevated sympathetic nervous system activity yet normal or reduced blood pressure. It represents a unique period of apparent healthy sympathetic hyperactivity. The present study models the blood pressure and heart rate (ECG R-R interval) responses to fluctuations in sympathetic nervous system activity aiming to understand neurocardiovascular transduction.

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Key Points: Polycystic ovary syndrome (PCOS) is a complex syndrome with cardiovascular risk factors, including obesity and insulin resistance. PCOS is also associated with high androgens, increases the risk of cardiovascular dysfunction in women. Due to the complexity of PCOS, had it has been challenging to isolate specific causes of the cardiovascular dysfunction.

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