Article
Biology
Elisa M. Fonseca, Tara A. Janes, Stephanie Fournier, Luciane H. Gargaglioni, Richard Kinkead
Summary: The study found that in pre-metamorphic bullfrog tadpoles, OX(1)Rs facilitate the expression of the motor command associated with air breathing, and different respiratory stimuli can have varying effects on respiratory motor output.
JOURNAL OF EXPERIMENTAL BIOLOGY
(2021)
Article
Fisheries
Muumin Iddi Hamad, Heiromin Amon Lamtane, Renalda Nanziga Munubi, Peter Vilhelm Skov
Summary: Photosynthesis and respiration have opposite effects on dissolved gases in earthen ponds. Daily variations in dissolved O2 and CO2 strongly affect the appetite and feed utilization in Nile tilapia. Hypoxia and hypercapnia individually and combined amplify the effects on appetite, growth rate, and feed conversion, while digestion is improved in groups exposed to fluctuations in dissolved oxygen and carbon dioxide.
Article
Medicine, General & Internal
Giacomo Strapazzon, Simon Rauch, Sandro Malacrida, Tomas Dal Cappello, Enrica Governo, Bruna Catuzzo, Simona Mrakic-Sposta, Margherita Urgesi, Marika Falla, Gianluca Cavoretto, Enrico Visetti, Guido Giardini, Hermann Brugger, Federico Prato
Summary: The use of an artificial air-pocket device (AAPD) during snow burial can delay the onset of hypoxemia and asphyxia, improving the survival time of individuals buried in avalanches.
Article
Pharmacology & Pharmacy
Christian Arias-Reyes, Sofien Laouafa, Natalia Zubieta-DeUrioste, Vincent Joseph, Aida Bairam, Edith M. Schneider Gasser, Jorge Soliz
Summary: The study reveals that EPO stimulates CSN activity under hypoxic conditions at lower concentrations, but inhibits it at higher concentrations. The inhibitory effect of high-dose EPO on CSN activity may be attributed to an increase in nitric oxide production.
FRONTIERS IN PHARMACOLOGY
(2021)
Article
Neurosciences
Piotr Niewinski, Stanislaw Tubek, Julian F. R. Paton, Waldemar Banasiak, Piotr Ponikowski
Summary: Bilateral carotid body resection (bCBR) eliminates hypoxic ventilatory response in congestive heart failure patients, resulting in lower blood oxygen saturation. However, the ventilatory response to hypercapnia is preserved, sufficient to maintain adequate oxygen saturation levels.
JOURNAL OF PHYSIOLOGY-LONDON
(2021)
Article
Biology
Caroline B. Ferreira, Talita M. Silva, Phelipe E. Silva, Claudio L. Castro, Catherine Czeisler, Jose J. Otero, Ana C. Takakura, Thiago S. Moreira
Summary: Mutations in the Phox2b gene, specifically the non-polyalanine repeat expansion mutations (NPARM) form, were found to affect respiratory control and the number of certain neurons. This study contributes to our understanding of the neuropathology of congenital central hypoventilation syndrome (CCHS) and provides new evidence for the mechanisms underlying NPARM CCHS.
Article
Clinical Neurology
Rup K. K. Sainju, Deidre N. N. Dragon, Harold B. B. Winnike, Laura Vilella, Xiaojin Li, Samden Lhatoo, Patrick Ten Eyck, Linder H. H. Wendt, George B. B. Richerson, Brian K. K. Gehlbach
Summary: It is believed that severe respiratory dysfunction caused by generalized convulsive seizures is a common mechanism for sudden unexpected death in epilepsy. This study examined the respiratory variability in epilepsy patients and found it to be a predictor of postictal hypoxemia severity, a potential biomarker for SUDEP risk. The study also found a relationship between respiratory variability and central CO2 drive.
Review
Biology
Eric Hermand, Francois J. Lhuissier, Aurelien Pichon, Nicolas Voituron, Jean-Paul Richalet
Summary: Periodic breathing, commonly seen in heart failure patients and individuals sleeping at high altitudes, has recently been studied in healthy subjects during exercise and wakefulness. The latest findings describe the physiological mechanisms underlying periodic breathing when exposed to various stimuli such as exercise, hypoxia, hyperoxia, hypercapnia, and acetazolamide. The research has revealed shorter breathing periods in healthy subjects compared to patients, and highlighted the cardiorespiratory interdependence in low frequency band, providing insights into the mechanisms of sympathetic activation during exercise in hypoxia. These nonlinear instabilities demonstrate the dynamic balance system allowing living organisms to adapt to environmental and internal perturbations.
Article
Neurosciences
Jing Zhu, Si Tang, Dong Zhao, Zhaofu Zeng, Huaheng Mo, Ke Hu
Summary: The study found that OXA plays a positive role in cognitive impairment induced by chronic intermittent hypoxia in mice, improving cognitive function by inhibiting hippocampal apoptosis and oxidative stress.
BRAIN RESEARCH BULLETIN
(2021)
Article
Neurosciences
Mei-Tsen Lin, Stephane Vinit, Kun-Ze Lee
Summary: The intermittent hypoxia associated with intermittent hypercapnia or sustained hypercapnia induced a greater ventilatory response than sustained hypercapnia during stimulus exposure. In subchronically injured animals, intermittent hypoxia associated with sustained hypercapnia or intermittent hypercapnic-hypoxia significantly enhanced tidal volume to a similar magnitude, but only intermittent hypercapnic-hypoxia and intermittent hypoxia were able to evoke long-term facilitation of tidal volume at the chronic injured stage. Mild intermittent hypercapnia did not further enhance the therapeutic effectiveness of intermittent hypoxia-induced respiratory recovery, but sustained hypercapnia associated with intermittent hypoxia may blunt ventilatory responses at the chronic injured stage.
EXPERIMENTAL NEUROLOGY
(2021)
Article
Physiology
Vivian Biancardi, Luis Gustavo A. Patrone, Mariane C. Vicente, Danuzia A. Marques, Kenia C. Bicego, Gregory D. Funk, Luciane H. Gargaglioni
Summary: Selective serotonin reuptake inhibitors (SSRIs), such as fluoxetine (FLX), are commonly used antidepressant drugs during pregnancy. This study investigated the effects of prenatal FLX exposure on breathing and brainstem monoaminergic groups in rats. The results showed that prenatal FLX exposure led to long-lasting, sex-specific changes in baseline breathing pattern and ventilatory responses to respiratory challenges. These changes were associated with alterations in the number of 5-HT and TH neurons in specific brain regions.
JOURNAL OF APPLIED PHYSIOLOGY
(2022)
Article
Physiology
Vivian Biancardi, Luis Gustavo A. Patrone, Mariane C. Vicente, Danuzia A. Marques, Kenia C. Bicego, Gregory D. Funk, Luciane H. Gargaglioni
Summary: The study shows that prenatal exposure to FLX has long-lasting and sex-specific effects on baseline breathing and brainstem monoaminergic groups in rats.
JOURNAL OF APPLIED PHYSIOLOGY
(2021)
Article
Multidisciplinary Sciences
Katsuhiko Tsunekawa, Kazumi Ushiki, Larasati Martha, Asuka Nakazawa, Rika Hasegawa, Risa Shimizu, Nozomi Shimoda, Akihiro Yoshida, Kiyomi Nakajima, Takao Kimura, Masami Murakami
Summary: This study aimed to verify whether the automated measurement of salivary cortisol concentration via sequential sampling could detect the differences in exercise stress between two altitudes. The results showed that the rate of change in salivary cortisol concentration during morning exercise was significantly higher in the higher-altitude camp than in the lower-altitude camp.
SCIENTIFIC REPORTS
(2022)
Article
Cell Biology
Pavel Tregub, Yuri Motin, Vladimir Kulikov, Pavel Kovzelev, Aleksandra Chaykovskaya, Irada Ibrahimli
Summary: Isolated exposure to intermittent hypoxia and permissive hypercapnia induces ultrastructural changes in mitochondria and endoplasmic reticulum, leading to maximal ischemic tolerance in neurons. This study compares the ultrastructural changes in hippocampal neurons after isolated and combined exposure to hypoxia and hypercapnia and correlates these changes with neuroprotective effects. The findings suggest that hypoxia and hypercapnia have varying effects on organelles responsible for neuron functions, with hypercapnia playing a dominant role in neuroprotection.
CELLULAR AND MOLECULAR NEUROBIOLOGY
(2023)
Review
Anesthesiology
Philip E. Bickler, John R. Feiner, Michael S. Lipnick, William McKleroy
Summary: Severe hypoxemia can present variably, sometimes without subjective complaints of dyspnea. The adequacy of cardiovascular compensation for oxygen delivery to tissues should be a focus in all hypoxemic patients.
Article
Neurosciences
Isato Fukushi, Kotaro Takeda, Makoto Uchiyama, Yuki Kurita, Mieczyslaw Pokorski, Shigefumi Yokota, Shuntaro Okazaki, Jouji Horiuchi, Yasuo Mori, Yasumasa Okada
JOURNAL OF COMPARATIVE NEUROLOGY
(2020)
Article
Biochemistry & Molecular Biology
Makoto Uchiyama, Akito Nakao, Yuki Kurita, Isato Fukushi, Kotaro Takeda, Tomohiro Numata, Ha Nam Tran, Seishiro Sawamura, Maximilian Ebert, Tatsuki Kurokawa, Reiko Sakaguchi, Alexander J. Stokes, Nobuaki Takahashi, Yasumasa Okada, Yasuo Mori
Article
Multidisciplinary Sciences
Yosuke Kono, Shigefumi Yokota, Isato Fukushi, Yosuke Arima, Hiroshi Onimaru, Shuntaro Okazaki, Kotaro Takeda, Itaru Yazawa, Masashi Yoshizawa, Yohei Hasebe, Keiichi Koizumi, Mieczyslaw Pokorski, Takako Toda, Kanji Sugita, Yasumasa Okada
SCIENTIFIC REPORTS
(2020)
Article
Physiology
Hiroshi Onimaru, Itaru Yazawa, Kotaro Takeda, Isato Fukushi, Yasumasa Okada
Summary: This study revealed the existence of NTS cells that are sensitive to hypercapnia and hypoxia, suggesting that astrocytes in the NTS region could serve as central gas sensors.
FRONTIERS IN PHYSIOLOGY
(2021)
Article
Multidisciplinary Sciences
Yasuki Koyanagi, Isato Fukushi, Masatoshi Nakamura, Kouji Suzuki, Nobuhito Oda, Takashi Aita, Hareaki Seki
Summary: Body weight-supported overground gait training (BWSOGT) for patients with Parkinson's disease (PD) improves gait ability and dynamic balance more than standard gait training.
Review
Chemistry, Analytical
Akira Umeda, Masahiro Ishizaka, Akane Ikeda, Kazuya Miyagawa, Atsumi Mochida, Hiroshi Takeda, Kotaro Takeda, Isato Fukushi, Yasumasa Okada, David Gozal
Summary: Measuring carbon dioxide concentrations is crucial in respiratory clinical practice, providing valuable information on gas exchange and ventilation. Various methods, such as assessing PaCO2 and using PtcCO2 monitors, are essential for evaluating respiratory function and disorders. Monitoring end-tidal PCO2 has become more widespread due to its multiple applications in different medical settings.
Article
Neurosciences
Itaru Yazawa, Shuntaro Okazaki, Shigefumi Yokota, Kotaro Takeda, Isato Fukushi, Masashi Yoshizawa, Hiroshi Onimaru, Yasumasa Okada
Summary: The study suggests that putative astrocytes and neurons in the ventral horn of the spinal cord may play a crucial role in maintaining synaptic function and metabolism to generate rhythms and patterns of locomotor-like activity by communicating with central pattern generator networks.
NEUROSCIENCE LETTERS
(2022)
Article
Multidisciplinary Sciences
Isato Fukushi, Masatoshi Nakamura, Shun-ichi Kuwana
Summary: The study found that wearing a facemask does not worsen dyspnea during light to moderate exercise but can worsen dyspnea during vigorous exercise. A cloth facemask increases dyspnea more than a surgical facemask during exercise and increases pulse rate during vigorous exercise, but not during less vigorous exercise. Additionally, wearing a facemask does not affect percutaneous arterial oxygen saturation during exercise regardless of the type of facemask.
Article
Physiology
Isato Fukushi, Kotaro Takeda, Mieczyslaw Pokorski, Yosuke Kono, Masashi Yoshizawa, Yohei Hasebe, Akito Nakao, Yasuo Mori, Hiroshi Onimaru, Yasumasa Okada
Summary: The study found that acute hypoxia results in a post-hypoxic persistent respiratory augmentation (PHRA) that is mediated by astrocytes. Further experiments indicate that the astrocytic TRPA1 channel is not directly involved in PHRA.
FRONTIERS IN PHYSIOLOGY
(2021)
Article
Neurosciences
Isato Fukushi, Shigefumi Yokota, Kotaro Takeda, Jiro Terada, Akira Umeda, Masashi Yoshizawa, Yosuke Kono, Yohei Hasebe, Hiroshi Onimaru, Mieczyslaw Pokorski, Yasumasa Okada
Summary: This study investigates the effects of the insomnia drug Suvorexant on the respiratory system and shows the involvement of orexin in respiratory control. Suvorexant suppresses the augmented ventilation in hypercapnia, but does not affect ventilation.
Article
Physiology
Masashi Yoshizawa, Isato Fukushi, Kotaro Takeda, Yosuke Kono, Yohei Hasebe, Keiichi Koizumi, Keiko Ikeda, Mieczyslaw Pokorski, Takako Toda, Yasumasa Okada
Summary: Microglia play an important role in the regulation of cardiorespiratory activities. They contribute to blood pressure regulation under normal blood oxygen conditions and enhance ventilatory responses during hypoxia.
JOURNAL OF PHYSIOLOGICAL SCIENCES
(2022)
Article
Neurosciences
Hiroshi Onimaru, Isato Fukushi, Keiko Ikeda, Itaru Yazawa, Kotaro Takeda, Yasumasa Okada, Masahiko Izumizaki
Summary: In this study, the effects of PAR1 activation on respiratory rhythm generation were investigated in brainstem-spinal cord preparations from newborn rats. The results showed that activation of astrocytes via PAR1 led to a decrease in inspiratory burst rate and hyperpolarization of respiratory-related neurons. After washout, weak excitatory responses appeared. Adenosine may be partially involved in the inhibitory effect of PAR1 activation.
Review
Respiratory System
Isato Fukushi, Mieczyslaw Pokorski, Yasumasa Okada
Summary: Dyspnea is a subjective experience of breathing discomfort that is common among patients with respiratory diseases. The underlying mechanisms are poorly understood, but it may result from a disconnect or mismatch between intended respiratory motor output and actual ventilatory output caused by the respiratory neuronal network.
RESPIRATORY INVESTIGATION
(2021)
Article
Physiology
Alyssa R. Mickle, Jesus D. Penaloza-Aponte, Richard Coffey, Natale A. Hall, David Baekey, Erica A. Dale
Summary: Closed-loop epidural stimulation (CL-ES) can improve respiratory deficits caused by cervical spinal cord injury, restoring diaphragm activity and enhancing contralateral activity. This treatment has the potential to lead to lasting recovery and device independence.
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2024)
Article
Physiology
Shawn Miller Jr, Edgar Juarez Lopez, Jessica M. L. Grittner, Brendan J. Dougherty
Summary: This study tested the impact of CO2 supplementation at different concentrations on ventilatory long-term facilitation (vLTF) in rats and found that 2% CO2 supplementation during and after acute, intermittent hypoxia (AIH) was sufficient to maintain isocapnia and induce significant vLTF.
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2024)
Article
Physiology
Behnam Vafadari, Yoshitaka Oku, Charlotte Tacke, Ali Harb, Swen Huelsmann
Summary: The preBo·tzinger Complex (preBo·tC) in the brainstem plays a critical role in generating respiratory rhythm. This study aimed to investigate the activity of inhibitory glycinergic neurons in the preBo·tC of anesthetized mice. Using juxtacellular recordings and optogenetic activation, the researchers were able to identify and characterize the activity pattern of these inhibitory neurons in relation to the breathing rhythm.
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2024)
Article
Physiology
Stephen M. Johnson, Maia G. Gumnit, Sarah M. Johnson, Tracy L. Baker, Jyoti J. Watters
Summary: Low-level activation of mu-opioid receptors can increase the amplitude of inspiratory bursts in neonatal rat brainstem-spinal cord preparations. Endomorphin-2, an endogenous ligand for these receptors, was found to have similar effects. Disinhibition of inhibitory synaptic transmission may not be involved in the changes induced by endomorphin-2, and different mechanisms may underlie the increase in burst amplitude and decrease in burst frequency.
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2024)
Article
Physiology
Raphael Martins de Abreu, Beatrice Cairo, Patricia Rehder-Santos, Claudio Donisete da Silva, Etore De Favari Signini, Juliana Cristina Milan-Mattos, Camila Akemi Sakaguchi, Aparecida Maria Catai, Alberto Porta
Summary: The purpose of this study was to determine the association between exercise capacity based on peak oxygen uptake (VO2peak) and resting cardiorespiratory coupling (CRC) levels. The results showed that resting CRC values were associated with exercise capacity in athletes but not in non-athletes.
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2024)
Article
Physiology
Sarah M. Russel, Raluca E. Gosman, Katherine Gonzalez, Joshua Wright, Dennis O. Frank-Ito
Summary: This study aimed to characterize the response of different nasal morphologies to airflow-related variables during rapid/deep inspiration. The results showed that notched nasal vestibules had higher resistance values and airflow velocities, while standard nasal vestibules had higher mucosal heat flux. Different nasal phenotypes may predispose individuals to exercise-induced rhinitis.
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2024)
Article
Physiology
Ivan Poliacek, Lukas Martvon, Michal Simera, Marcel Veternik, Jakub Misek, Lucia Cibulkova, Kimberly E. Iceman, Donald C. Bolser, Teresa Pitts
Summary: An animal model study evaluated the effects of an abdominal incision on cough and swallow, revealing that abdominal wall manipulations can increase pharyngeal muscle activity during swallow without affecting the cough reflex. Swallowing tended to occur more during the inspiratory phase. The results highlight the important role of abdominal wall sensory feedback in regulating swallow motor patterns.
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2024)
Article
Physiology
Rui Yu, Tatsuma Okazaki, Yuzhuo Ren, Junko Okuyama, Satoru Ebihara, Shin-Ichi Izumi
Summary: Body postures significantly influence respiratory muscle force, cough pressure, subjective ease of coughing, and pulmonary function. The 60-degree semi-recumbent posture and sitting posture show better results compared to the supine posture.
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2024)
Article
Physiology
Suzuna Sato, Koji Ishida, Noriko I. Tanaka, Keisho Katayama
Summary: Respiratory muscle endurance training has beneficial effects on whole-body endurance performance. A novel high-intensity interval (HII) protocol is found to enhance the efficacy of respiratory muscle training programs.
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2024)
Letter
Physiology
R. Arieli
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2024)
Correction
Physiology
Ivan Poliacek, Michal Simera, Marcel Veternik, Zuzana Kotmanova, Teresa Pitts, Jan Hanacek, Jana Plevkova, Peter Machac, Nadezda Visnovcova, Jakub Misek, Jan Jakus
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2024)
Article
Physiology
Dimitrios I. Bourdas, Nickos D. Geladas
Summary: This study examined the effects of breath-hold training on the performance of novice and elite breath-hold divers. The results showed that breath-hold training significantly improved red blood cell concentration, hemoglobin oxygen saturation steady state duration, and breath-hold time in novice divers. Elite divers had better breath-hold performance and higher peak mean arterial pressure compared to novices. The study suggests that breath-hold training can enhance the performance of divers.
RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY
(2024)