Publications by authors named "R E De la Vega"

516 Publications

A transient decrease in heart rate with unilateral and bilateral galvanic vestibular stimulation in healthy humans.

Eur J Neurosci 2021 Jun 2. Epub 2021 Jun 2.

Benemérita Universidad Autónoma de Puebla, Instituto de Fisiología, México.

The study of cardiovascular function with Galvanic Vestibular Stimulation has provided evidence on the neural structures that are involved in the vestibulo-autonomic reflex. This study determined if the effect on heart rate using Galvanic Vestibular Stimulation persists after provoking a sympathetic response and if this response differs when using unilateral or transmastoid (bilateral) stimulation. We analyzed heart rate and heart rate variability using unilateral and transmastoid Galvanic Vestibular Stimulation combined with cardiovascular reflex evoked by postural change in 24 healthy human subjects. Three electrode configurations were selected for unilateral stimulation considering the anatomical location of each semicircular canal. We compared recordings performed in seated and standing positions, and with unilateral and transmastoid stimulation. With subjects seated, a significant transient decrease in heart rate was observed with unilateral stimulation. With transmastoid stimulation, heart rate decreased in both seated and standing positions. Average intervals between normal heartbeats recorded with stimulation resemble parasympathetic cardiac function induced by auricular vagal nerve stimulation. Our results indicate that unilateral stimulation does not eliminate the natural heart rate increase caused by orthostatic hypotension. In contrast, transmastoid stimulation provoked a transient reduction in heart rate, even when subjects were standing. These responses should be considered while performing experiments with Galvanic Vestibular Stimulation and subsequent effects in cardiac regulation mechanisms.
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http://dx.doi.org/10.1111/ejn.15338DOI Listing
June 2021

Proton Therapy for Breast Cancer: A Consensus Statement from the Particle Therapy Cooperative Group (PTCOG) Breast Cancer Subcommittee.

Int J Radiat Oncol Biol Phys 2021 May 25. Epub 2021 May 25.

Department of Radiation Oncology, Massachusetts General Hospital, Boston, MA.

Radiotherapy plays an important role in the multidisciplinary management of breast cancer. Recent years have seen improvements in breast cancer survival as well as a greater appreciation of potential long-term morbidity associated with the dose and volume of irradiated organs. Proton therapy reduces the dose to non-target structures while optimizing target coverage. However, there remain additional financial costs associated with proton therapy, despite reductions over time, and studies have yet to demonstrate that protons improve upon treatment outcomes achieved with photon radiotherapy. There remains considerable heterogeneity in proton patient selection and techniques, and the rapid technological advances in the field have potential to impact evidence evaluation given the long latency period for breast cancer radiotherapy recurrence and late effects. In this consensus statement we assess the data available to the radiation oncology community of proton therapy for breast cancer, provide expert consensus recommendations on indications and technique, and highlight ongoing trials cost-effectiveness analyses, and key areas for future research.
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http://dx.doi.org/10.1016/j.ijrobp.2021.05.110DOI Listing
May 2021

Prolonged Glucagon Infusion Does Not Affect Energy Expenditure in Individuals with Overweight/Obesity: A Randomized Trial.

Obesity (Silver Spring) 2021 06;29(6):1003-1013

Translational Research Institute, AdventHealth, Orlando, Florida, USA.

Objective: The aim of this study was to determine the effects of prolonged (72 hours) glucagon administration at a low dose (LD) (12.5 ng/kg/min) and high dose (HD) (25 ng/kg/min) on energy expenditure (EE) in healthy individuals with overweight or obesity.

Methods: Thirty-one healthy participants with overweight or obesity (BMI of 27-45 kg/m , 26-55 years old, 23 females) were randomized into LD, HD, or placebo groups and underwent 72-hour intravenous infusion of glucagon. Whole-room calorimetry was used to assess EE and substrate use during five overnight stays (2 days at baseline, 3 days of infusion) and during two 24-hour stays (baseline vs. day 3). Blood was sampled at regular intervals throughout the inpatient stay and analyzed for glucagon and biomarkers of metabolism.

Results: HD infusion elevated plasma glucagon levels compared with the placebo and LD infusion (P < 0.001). Sleeping, basal, and 24-hour EE was not significantly different among groups at any time point. Those receiving HD had significantly higher basal fat oxidation (Fat Ox) at days 2 and 3 than those receiving the placebo (P < 0.05); however, no differences in 24-hour Fat Ox were observed among groups (baseline vs. day 3).

Conclusions: An HD plasma glucagon infusion over 72 hours does not increase any aspects of EE in healthy individuals with overweight or obesity.
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http://dx.doi.org/10.1002/oby.23141DOI Listing
June 2021

Proton radiotherapy for infant rhabdomyosarcoma: Rethinking young age as an adverse prognostic factor.

Radiother Oncol 2021 May 20. Epub 2021 May 20.

Department of Radiation Oncology, University of Florida College of Medicine, Jacksonville, FL, United States. Electronic address:

Background & Purpose: In infants with rhabdomyosarcoma, young age is considered an adverse prognostic factor and treatment is often attenuated to reduce side effects. Proton therapy may improve the therapeutic ratio in these patients. We report outcomes in infants with rhabdomyosarcoma treated with proton therapy.

Materials & Methods: Between 2009 and 2019, 37 infants <24 months old with non-metastatic rhabdomyosarcoma received proton therapy. Local control (LC), progression-free survival (PFS), and overall survival (OS) were estimated using the Kaplan-Meier product limit. The log-rank test assessed significance between selected prognostic factors. Toxicity was graded per CTCAEv5.0.

Results: Median follow-up was 5.1 years. Overall, 76% of patients had an unfavorable primary site. Median dose was 50.4GyRBE. At 5 years, LC, PFS, and OS rates were 83%, 78%, and 83%. On univariate analysis, 5-year LC and OS were inferior for favorable versus unfavorable disease sites (67% vs 89%, 67% vs 89%, respectively; p<.05) and 5-year OS was superior in stage 3 versus stage 1-2 disease (91% vs 69%; p=.05), owing to inclusion of nasal ala patients among stage 1. Of 9 recurrences, 7 were in-field, 4 occurring in infants with nasal ala primaries. Recategorizing nasal ala as an unfavorable site resulted in 100% 5-year LC and OS for favorable sites. Six infants experienced late grade 3 toxicity. None developed grade 4 or 5 late toxicity.

Conclusions: Young age alone may not be an adverse prognostic factor provided infants receive local therapy similar to older children. Consideration should be given to classifying nasal ala primaries as an unfavorable site.
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http://dx.doi.org/10.1016/j.radonc.2021.05.017DOI Listing
May 2021

Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry Imaging in Biology.

Chem Rev 2021 May 21. Epub 2021 May 21.

Atomic Medicine Initiative, University of Technology Sydney, Broadway, New South Wales 2007, Australia.

Elemental imaging gives insight into the fundamental chemical makeup of living organisms. Every cell on Earth is comprised of a complex and dynamic mixture of the chemical elements that define structure and function. Many disease states feature a disturbance in elemental homeostasis, and understanding how, and most importantly where, has driven the development of laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) as the principal elemental imaging technique for biologists. This review provides an outline of ICP-MS technology, laser ablation cell designs, imaging workflows, and methods of quantification. Detailed examples of imaging applications including analyses of cancers, elemental uptake and accumulation, plant bioimaging, nanomaterials in the environment, and exposure science and neuroscience are presented and discussed. Recent incorporation of immunohistochemical workflows for imaging biomolecules, complementary and multimodal imaging techniques, and image processing methods is also reviewed.
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http://dx.doi.org/10.1021/acs.chemrev.0c01219DOI Listing
May 2021