Tumor bearing in untreated breast cancer decreases exercise tolerance without lowering maximal oxygen uptake in rats.

Breast cancer patients' maximal O uptake (V̇Omax) values average 60-80% of age-predicted values which is often attributed to adjuvant therapy rather than risk factors, comorbidities, or the tumor and associated factors (e.g., pro-inflammatory cytokines).

Bulk and regional diaphragm blood flow during chemical hyperpnea in pulmonary hypertensive rats.

Pulmonary hypertension (PH) is a disease characterized by increased pulmonary arterial pressures, impaired gas exchange, dyspnea, and diaphragmatic dysfunction. Specifically, in PH, the diaphragm displays impaired contractility, vascular dysfunction, and blood flow redistribution toward less mechanically advantageous regions such as the ventral costal and crural diaphragm at rest and during submaximal exercise. While diaphragm blood flow is not a limitation to maximal exercise in health, whether it limits diaphragm function in PH is unknown.

Protein kinase C epsilon contributes to chronic mechanoreflex sensitization in rats with heart failure.

We investigated second-messenger signalling components linked to the stimulation of G protein-coupled receptors (e.g. thromboxane A and bradykinin B2 receptors) on the sensory endings of thin fibre muscle afferents in the chronic mechanoreflex sensitization in rats with myocardial infarction-induced heart failure with reduced ejection fraction (HF-rEF).

Impaired microvascular reactivity in patients treated with 5-fluorouracil chemotherapy regimens: Potential role of endothelial dysfunction.

Background: 5-fluorouracil (5-FU) is the second most common cancer chemotherapy associated with short- and long-term cardiotoxicity. Although the mechanisms mediating these toxicities are not well understood, patients often present with symptoms suggestive of microvascular dysfunction. We tested the hypotheses that patients undergoing cancer treatment with 5-FU based chemotherapy regimens would present with impaired microvascular reactivity and that these findings would be substantiated by decrements in endothelial nitric oxide synthase (eNOS) gene expression in 5-FU treated human coronary artery endothelial cells (HCAEC).

Cardiac changes in collegiate athletes following SARS-CoV-2 infection and quarantine: a prospective Case-Control study.

Objective: Athletes are susceptible to acute respiratory tract infections, including SARS-CoV-2, which can affect cardiovascular function. We aimed to evaluate the impact of COVID-19 infection and quarantine on cardiac function in male and female collegiate athletes.

Methods: We conducted a single-center, prospective, case-control study and performed transthoracic echocardiography in a diverse group of convalescent SARS-CoV-2-positive athletes following a 10-14-day quarantine, matched to non-SARS-CoV-2 athletes.

Head-up tilt does not enhance prostate tumor perfusion or oxygenation in young rats.

Solid tumors contain hypoxic regions that contribute to anticancer therapy resistance. Thus, mitigating tumor hypoxia may enhance the efficacy of radiation therapy which is commonly utilized for patients with prostate cancer. Increasing perfusion pressure in the prostate with head-up tilt (HUT) may augment prostate tumor perfusion and decrease hypoxia.

Inorganic nitrate supplementation may improve diastolic function and the O cost of exercise in cancer survivors: a pilot study.

In non-cancer populations, inorganic dietary nitrate (NO) supplementation is associated with enhanced cardiorespiratory function but remains untested in patients with a history of cancer. Therefore, this pilot study sought to determine if oral NO supplementation, as a supportive care strategy, increases left ventricular (LV) function and exercise performance in survivors of cancer treated with anticancer therapy while simultaneously evaluating the feasibility of the methods and procedures required for future large-scale randomized trials. Two cohorts of patients with a history of cancer treated with anticancer chemotherapy were recruited.

Association between Serum Biomarkers with Postoperative Complications and Delay of Adjuvant Chemotherapy Initiation in Ovarian Cancer Patients Undergoing Primary Cytoreductive Surgery: A Pilot Study.

This study sought to describe and relate the factors associated with complications and delays in adjuvant chemotherapy in patients with ovarian cancer treated with primary cytoreductive surgery. Serum from patients diagnosed with ovarian cancer scheduled for primary cytoreductive surgery were analyzed for prealbumin, 25-OH Vitamin D, intracellular adhesion molecule 1 (ICAM-1), interleukin 6 (IL-6), interleukin 8 (IL-8), monocyte chemoattractant protein 1 (MCP-1), monocyte chemoattractant protein 2 (MCP-2), macrophage derived chemokine (MDC). Postoperative complications were identified using common terminology criteria for adverse events 4.

A bench to bedside perspective on anthracycline chemotherapy-mediated cardiovascular dysfunction: challenges and opportunities. A symposium review.

Cardiovascular diseases (CVD) are the leading cause of death worldwide and the risk of developing CVD is markedly increased following anthracycline chemotherapy treatment. Anthracyclines are an essential component of the cancer treatment regimen used for common forms of cancer in male and female children, adolescents, young adults, and older adults. Increased CVD risk with anthracyclines occurs, in part, due to vascular dysfunction-impaired endothelial function and arterial stiffening.

A Case Series of Diverse Cardiac Abnormalities in Collegiate Athlete with COVID-19: Role for Multimodality Imaging.

Introduction: Since the COVID-19 pandemic there is concern for subclinical cardiac pathology in the absence of clinical symptoms in collegiate athletes, we present 4 cases of abnormal left ventricular global longitudinal strain (LVGLS), a "red-flag" for potential COVID-19 myocardial disease, following diagnosis with diverse abnormalities reported via multimodality imaging weeks into recovery.

Methods: Cardiac imaging studies consisting of transthoracic echocardiography (TTE) and cardiovascular magnetic resonance imaging (CMR) were performed 10 days post-COVID-19 diagnosis and several weeks into recovery.

Results: Initial TTE revealed abnormal left ventricular global longitudinal strain (LVGLS), an identified "red-flag" for potential COVID-19 myocardial disease.

A Non-Invasive Hydration Monitoring Technique Using Microwave Transmission and Data-Driven Approaches.

Dehydration in the human body arises due to inadequate replenishment of fluids. An appropriate level of hydration is essential for optimal functioning of the human body, and complications ranging from mild discomfort to, in severe cases, death, could result from a neglected imbalance in fluid levels. Regular and accurate monitoring of hydration status can provide meaningful information for people operating in stressful environmental conditions, such as athletes, military professionals and the elderly.

Effects of pulmonary hypertension on microcirculatory hemodynamics in rat skeletal muscle.

Pulmonary hypertension (PH) has previously been characterized as a disease of the pulmonary vasculature that subsequently results in myocardial dysfunction. Heart failure compromises skeletal muscle microvascular function, which contributes to exercise intolerance. Therefore, we tested the hypothesis that such changes might be present in PH.

Capillary hemodynamics and contracting skeletal muscle oxygen pressures in male rats with heart failure: Impact of soluble guanylyl cyclase activator.

In heart failure with reduced ejection fraction (HFrEF), nitric oxide-soluble guanylyl cyclase (sGC) pathway dysfunction impairs skeletal muscle arteriolar vasodilation and thus capillary hemodynamics, contributing to impaired oxygen uptake (V̇O) kinetics. Targeting this pathway with sGC activators offers a new treatment approach to HFrEF. We tested the hypotheses that sGC activator administration would increase the O delivery (Q̇O)-to-V̇O ratio in the skeletal muscle interstitial space (POis) of HFrEF rats during twitch contractions due, in part, to increases in red blood cell (RBC) flux (f), velocity (V), and capillary hematocrit (Hct).

Thromboxane A receptors contribute to the exaggerated exercise pressor reflex in male rats with heart failure.

Mechanical and metabolic signals associated with skeletal muscle contraction stimulate the sensory endings of thin fiber muscle afferents and produce reflex increases in sympathetic nerve activity and blood pressure during exercise (i.e., the exercise pressor reflex; EPR).

The effects of pulmonary hypertension on skeletal muscle oxygen pressures in contracting rat spinotrapezius muscle.

New Findings: What is the central question of this study? Does impairment in the dynamics of O transport in skeletal muscle during a series of contractions constitute a potential mechanism underlying reduced exercise capacity in pulmonary hypertension? What is the main finding and its importance? Pulmonary hypertension compromises the dynamic matching of skeletal muscle O delivery-to-utilization following contraction onset in the rat spinotrapezius muscle. These results implicate a role for vascular dysfunction in the slow kinetics and exercise intolerance present in pulmonary hypertension.

Abstract: Pulmonary hypertension (PH) is characterized by pulmonary vascular dysfunction and exercise intolerance due, in part, to compromised pulmonary and cardiac function.

Does wearing a facemask decrease arterial blood oxygenation and impair exercise tolerance?

Introduction: Concerns have been raised that COVID-19 face coverings compromise lung function and pulmonary gas exchange to the extent that they produce arterial hypoxemia and hypercapnia during high intensity exercise resulting in exercise intolerance in recreational exercisers. This study therefore aimed to investigate the effects of a surgical, flannel or vertical-fold N95 masks on cardiorespiratory responses to incremental exercise.

Methods: This investigation studied 11 adult males and females at rest and while performing progressive cycle exercise to exhaustion.

Influence of muscular contraction on vascular conductance during exercise above versus below critical power.

We tested the hypothesis that limb vascular conductance (LVC) would increase during the immediate recovery phase of dynamic exercise above, but not below, critical power (CP) indicating a threshold for muscular contraction-induced impedance of limb blood flow (LBF). CP (115 ± 26 W) was determined in 7 men and 7 women who subsequently performed ∼5 min of near-supine cycling exercise both below and above CP. LVC demonstrated a greater increase during immediate recovery and remained significantly higher following exercise above, compared to below, CP (all p < 0.

Arterial stiffness is associated with cardiovascular and cancer mortality in cancer patients: Insight from NHANESIII.

Background: Cancer survivors are at greater risk for cardiovascular disease (CVD) than second malignancy, resulting in a decreased quality of life and increased cost of care. Additional knowledge of CVD prevention by identifying possible risk factors has clinical relevance. Our main objective was to determine the relevance of a clinical index of arterial stiffness, pulse pressure, in predicting CVD mortality in cancer patients, with a second objective to examine its relationship with cancer mortality.

Lower endothelium-dependent microvascular function in adult breast cancer patients receiving radiation therapy.

Purpose: Cancer patients with a history of radiotherapy are at an increased risk of ischemic heart disease. Preclinical animal studies demonstrate markedly impaired acetylcholine (ACh)-mediated endothelium-dependent vasorelaxation within days to weeks post-irradiation, however, whether microvascular function is affected in the intact human circulation during cancer radiation therapy has yet to be determined.

Materials And Methods: Using laser-Doppler flowmetry, microvascular endothelium-dependent and independent responses were evaluated through iontophoresis of acetylcholine (ACh) (part 1, n = 7) and sodium nitroprusside (SNP) (part 2, n = 8), respectively, in women currently receiving unilateral chest adjuvant radiation therapy for breast cancer.

Exaggerated sympathetic and cardiovascular responses to dynamic mechanoreflex activation in rats with heart failure: Role of endoperoxide 4 and thromboxane A receptors.

The primary purpose of this investigation was to determine the role played by endoperoxide 4 receptors (EP4-R) and thromboxane A receptors (TxA-R) during isolated dynamic muscle mechanoreflex activation in rats with heart failure with reduced ejection fraction (HF-rEF) and sham-operated healthy controls. We found that injection of the EP4-R antagonist L-161,982 (1 μg) into the arterial supply of the hindlimb had no effect on the peak pressor response to dynamic hindlimb muscle stretch in HF-rEF (n = 6, peak ∆MAP pre: 27 ± 7; post: 27 ± 4 mm Hg; P = 0.99) or sham (n = 6, peak ∆MAP pre: 15 ± 3; post: 13 ± 3 mm Hg; P = 0.

Effects of high-intensity training on prostate cancer-induced cardiac atrophy.

Background: Recent evidence suggests prostate cancer independent of treatment has atrophic effects on whole heart and left ventricular (LV) masses, associated with reduced endurance exercise capacity. In a pre-clinical model, we tested the hypothesis that high-intensity training could prevent cardiac atrophy with prostate cancer and alter cardiac protein degradation mechanisms.

Methods: Dunning R-3327 AT-1 prostate cancer cells (1×10) were injected into the ventral prostate lobe of 5-6 mo immunocompetent Copenhagen rats (n=24).