Read by QxMD icon Read

intermittent hypoxia

Barbara J Morgan, Nicole Schrimpf, Morgan Rothman, Ann Mitzey, Mark S Brownfield, Robert C Speth, John M Dopp
Chronic intermittent hypoxia (CIH) increases basal sympathetic nervous system activity, augments chemoreflex-induced sympathoexcitation, and raises blood pressure. All effects are attenuated by systemic or intracerebroventricular administration of angiotensin II type 1 receptor (AT1 R) antagonists. This study aimed to quantify the effects of CIH on AT1 R- and AT2 R-like immunoreactivity in the rostroventrolateral medulla (RVLM) and paraventricular nucleus of the hypothalamus (PVN), central regions that are important components of the extended chemoreflex pathway...
March 21, 2018: Clinical and Experimental Hypertension: CHE
Benedikt Treml, Axel Kleinsasser, Karl-Heinz Stadlbauer, Iris Steiner, Werner Pajk, Michael Pilch, Martin Burtscher, Hans Knotzer
As is known, hypoxia leads to an increase in microcirculatory blood flow of the skin in healthy volunteers. In this pilot study, we investigated microcirculatory blood flow and reactive hyperemia of the skin in healthy subjects in normobaric hypoxia. Furthermore, we examined differences in microcirculation between hypoxic subjects with and without short-term acclimatization, whether or not skin microvasculature can acclimatize. Fourty-six healthy persons were randomly allocated to either short-term acclimatization using intermittent hypoxia for 1 h over 7 days at an FiO2 0...
2018: Frontiers in Physiology
Christian Lind Malte, Jonas Bundgaard, Michael Schou Jensen, Mads Frost Bertelsen, Tobias Wang
Morphine and other opioids cause respiratory depression in high doses and lower the ventilatory responses to hypoxia and hypercapnia in mammals. Recent studies indicate that turtles respond similarly, but although they are used routinely for post-surgical analgesia, little is known about the physiological effects of opioids in reptiles. We therefore investigated the effects of morphine (10 and 20 mg kg-1 ) on gas exchange and ventilation in six dwarf caiman (Paleosuchus palpebrosus) using pneumotachography in a crossover design...
March 16, 2018: Comparative Biochemistry and Physiology. Part A, Molecular & Integrative Physiology
Kay D Beharry, Charles L Cai, Taimur Ahmad, Sibel Guzel, Gloria B Valencia, Jacob V Aranda
Neonatal intermittent hypoxia (IH) followed by re-oxygenation in normoxia or supplemental oxygen (IHR) increases the risk for severe retinopathy of prematurity (ROP). The exact timing for the onset of retinal damage which may guide strategic interventions during retinal development, is unknown. We tested the hypothesis that chronic exposure of the immature retina to neonatal IH induces early manifestations of retinal damage that can be utilized as key time points for strategic pharmacologic intervention. Newborn rats were exposed to IH within 2 hours of birth (P0) until P14, or allowed to recover in room air (RA) from P14 to P21 (IHR)...
2018: Journal of Nature and Science
Fu-Chao Yu, Chu-Xiao Yuan, Jia-Yi Tong, Guang-Hao Zhang, Fang-Ping Zhou, Fang Yang
Intermittent hypoxia (IH) induced by obstructive sleep apnea (OSA) is the key factor in oxidative stress and the concomitant inflammation of endothelial cells (ECs). In recent years, the lipid sphingosine-1-phosphate (S1P) has been reported to probably play a central role in inflammatory diseases. However, its role in IH-induced endothelial injury remains uncertain. In this study, we investigated the IH-induced ECs inflammation and apoptosis, as well as the role of S1P in both. First, human umbilical vein endothelial cells (HUVECs) were treated with IH to explore the mechanism of S1P and S1P microbubbles (S1P-MBs) in HUVECs with altered function...
March 16, 2018: Biochemical and Biophysical Research Communications
Xiaofeng Zhang, Lijun Rui, Mei Wang, Hairong Lian, Liming Cai
BACKGROUND In the present study, we aimed to investigate the effects of sinomenine (SIN) on chronic intermittent hypoxia (CIH)- induced lung injury in rats, and to explore the underlying mechanisms. MATERIAL AND METHODS To perform the investigation, a CIH rat model was established. ELISA assay was applied to detect the level of inflammatory cytokines. Oxidative stress bio-markers (MDA, SOD, and CAT) were determined in lung tissues. In addition, the expression level of NADPH oxidase 2 (Nox2) was analyzed by Western blotting and qRT-PCR, respectively...
March 17, 2018: Medical Science Monitor: International Medical Journal of Experimental and Clinical Research
Charles Cai, Taimur Ahmad, Gloria B Valencia, Jacob V Aranda, Jiliu Xu, Kay D Beharry
OBJECTIVES: Extremely low gestational age neonates with chronic lung disease requiring oxygen therapy frequently experience fluctuations in arterial oxygen saturation or intermittent hypoxia (IH). These infants are at risk for multi-organ developmental delay, reduced growth, and short stature. The growth hormone (GH)/insulin-like growth factor-I (IGF-1) system, an important hormonal regulator of lipid and carbohydrate metabolism, promotes neonatal growth and development. We tested the hypothesis that increasing episodes of IH delay neonatal growth by influencing the GH/IGF-I axis...
March 8, 2018: Growth Hormone & IGF Research
Ryan L Sheppard, Joshua M Swift, Aaron Hall, Richard T Mahon
Introduction: Individuals with a known susceptibility to high altitude pulmonary edema (HAPE) demonstrate a reduced ventilation response and increased pulmonary vasoconstriction when exposed to hypoxia. It is unknown whether reduced sensitivity to hypercapnia is correlated with increased incidence and/or severity of HAPE, and while acute exercise at altitude is known to exacerbate symptoms the effect of exercise training on HAPE susceptibility is unclear. Purpose: To determine if chronic intermittent hypercapnia and exercise increases the incidence of HAPE in rats...
2018: Frontiers in Physiology
Nika Karimi, Marta Kelava, Perin Kothari, Nicole M Zimmerman, A Marc Gillinov, Andra E Duncan
BACKGROUND: Patients with obstructive sleep apnea (OSA) experience intermittent hypoxia, hypercarbia, and sympathetic activation during sleep, which increases risk for paroxysmal atrial fibrillation and other cardiac arrhythmias. Whether patients with OSA experience increased episodes of atrial fibrillation after cardiac surgery is unclear. We examined whether patients at increased risk for OSA, assessed by the STOP-BANG (snoring, tired during the day, observed stop breathing during sleep, high blood pressure, body mass index more than 35 kg/m, age more than 50 years, neck circumference more than 40 cm, and male gender) questionnaire, had a higher incidence of new-onset postoperative atrial fibrillation after cardiac surgery...
March 12, 2018: Anesthesia and Analgesia
S Druyan, M Ruzal, D Shinder, A Haron
The prenatal circulatory system is adaptive and capable of plasticity designed for the needs of the growing tissue. When a broiler embryo is faced with hypoxic stress, the process of angiogenesis in tissues begins. Exposure to hypoxic conditions of 17% oxygen during the chorioallantoic membrane (CAM) development (E5 to E12) affected the circulatory system and contributed to an increase in the blood oxygen carrying capacity. The present study aimed to evaluate the effects of hypoxic exposure during CAM development on post-hatch performance of broilers and to examine whether hypoxic exposure improved sustainability of birds exposed to acute heat stress...
March 8, 2018: Poultry Science
E Nicole Wilson, Marc Anderson, Brina Snyder, Phong Duong, Jenny Trieu, Derek A Schreihofer, Rebecca L Cunningham
Sleep apnea is a common sleep disorder characterized by intermittent periods of low blood oxygen levels. The risk for sleep apnea increases with age and is more prevalent in men than women. A common comorbidity of sleep apnea includes male sexual dysfunction, but it is not clear if a causal relationship exists between sleep apnea and sexual dysfunction. Possible mechanisms that link these two disorders include oxidative stress and testosterone. Oxidative stress is elevated in clinical patients with sleep apnea and in rodents exposed to chronic intermittent hypoxia (CIH), an animal model for apnea-induced hypopnea...
March 8, 2018: Physiology & Behavior
Stéphanie Conotte, Alexandra Tassin, Raphaël Conotte, Jean-Marie Colet, Karim Zouaoui Boudjeltia, Alexandre Legrand
Chronic intermittent hypoxia (ChIH) is a dominant feature of obstructive sleep apnoea (OSA) and is associated to metabolic alterations and oxidative stress (OS). Although management of OSA is well established, the research of new biomarkers that are independent of confounding factors remains necessary to improve the early detection of comorbidity and therapeutic follow-up. In this study, the urinary metabonomic profile associated to intermittent hypoxia was evaluated in a mouse model. When exposed to intermittent hypoxia, animals showed a significant alteration in energy metabolism towards anaerobic pathways and signs of OS imbalance...
March 6, 2018: Respiratory Physiology & Neurobiology
Huina Zhang, Fan Yang, Yichen Guo, Li Wang, Fang Fang, Hao Wu, Shaoping Nie, Yifan Wang, Man-Lung Fung, Yu Huang, Haiteng Deng, Yanwen Qin, Xinliang Ma, Yongxiang Wei
OBJECTIVE: Obstructive sleep apnea hypopnea syndrome (OSAHS) is an independent risk factor for many clinical complications. However, how OSAHS cause multiple organ injury and initiate inter-organ communication remains unclear. Moreover, despite it is well-recognized that chronic intermittent hypoxia (CIH) is a main feature of OSAHS, specific contribution of CIH to overall OSAHS-initiated pathological complications remains unclear. This study aimed to use an unbiased proteomic approach to determine whether OSAHS alters protein profiles of serum extracellular microvesicles (SEMVs) and how CIH contributes to such alterations...
March 6, 2018: Metabolism: Clinical and Experimental
Ibis M Agosto, Nicole L Nichols, Gordon S Mitchell
Although systemic inflammation induced by even a low dose of lipopolysaccharide (LPS, 100uL/kg) impairs respiratory motor plasticity, little is known concerning cellular mechanisms giving rise to this inhibition. Phrenic motor facilitation (pMF) is a form of respiratory motor plasticity elicited by pharmacological agents applied to the cervical spinal cord, or by acute intermittent hypoxia (AIH; 3, 5 min hypoxic episodes); when elicited by AIH, pMF is known as phrenic long-term facilitation (pLTF). AIH consisting of moderate hypoxic episodes (mAIH, PaO2 = 35-55 mmHg) elicits pLTF via the Q- pathway to pMF, a mechanism that requires spinal serotonin (5HT2) receptor activation and new BDNF protein synthesis...
March 7, 2018: Journal of Neurophysiology
Qian Han, Guihua Li, Mary SiuMan Ip, Yuelin Zhang, Zhe Zhen, Judith ChoiWo Mak, Nuofu Zhang
Obstructive sleep apnoea (OSA) characterized by intermittent hypoxia (IH) is closely associated with cardiovascular diseases. IH confers cardiac injury via accelerating cardiomyocyte apoptosis, whereas the underlying mechanism has remained largely enigmatic. This study aimed to explore the potential mechanisms involved in the IH-induced cardiac damage performed with the IH-exposed cell and animal models and to investigate the protective effects of haemin, a potent haeme oxygenase-1 (HO-1) activator, on the cardiac injury induced by IH...
March 7, 2018: Journal of Cellular and Molecular Medicine
Lei Gao, Jun Liu, Yongmei Hao, Zengren Zhao, Huilian Tan, Jie Zhang, Ning Meng, Qinghou Zheng, Zhen Wang, Yi Zhang
Objectives: Inflammation is involved in various forms of pulmonary arterial hypertension (PAH). Although the pathophysiology of PAH remains uncertain, NF-κB and p38 mitogen-activated protein kinase (p38 MAPK) has been reported to be associated with many inflammatory mediators of PAH. This study aimed to evaluate the effect of chronic intermittent hypobaric hypoxia (CIHH) on pulmonary inflammation and remodeling in monocrotaline (MCT) induced PAH in rats. Materials and Methods: An in vivo model of PAH induced by MCT was employed...
March 2018: Iranian Journal of Basic Medical Sciences
Z-W Wen, D-S Liang, X-H Cai, J Chen
OBJECTIVE: To investigate the role of AMPK-mTOR signal pathway in brain injury induced by chronic intermittent hypoxia (CIH) in young rats. MATERIALS AND METHODS: Forty healthy male Sprague-Dawley rats (3-4 weeks old, weighing 80-100 g) were randomly assigned to four groups: 2-week-CIH group (2IH), 4-week-CIH group (4IH), 2-week-simulated air control group (2AC) and 4-week-simulated air control group (4AC). TUNEL staining was used to detect the cell apoptosis in the hippocampus and pre-frontal cortexes, respectively...
February 2018: European Review for Medical and Pharmacological Sciences
Han Ying Tng, Win Pa Pa Thu, Susan Logan, Izzuddin M Aris, Jane Cauley, Eu Leong Yong
The relationship between sleep apnea and bone health remains controversial. This study explored the relationship between sleep apnea and femoral neck BMD in midlife Asian women. Partner-witnessed apnea predicted higher femoral neck BMD, an effect validated by the STOP index. Our findings suggest that sleep apnea may protect bone health. PURPOSE: The menopause transition is associated with decline in bone mineral density (BMD) and sleep quality. However, any relationship between these two factors remains controversial...
March 5, 2018: Archives of Osteoporosis
Erika Yamada, Noriko Himori, Hiroshi Kunikata, Kazuko Omodaka, Hiromasa Ogawa, Masakazu Ichinose, Toru Nakazawa
PURPOSE: Sleep apnoea syndrome (SAS) is often associated with glaucoma, and intermittent hypoxia, present in SAS, can contribute to glaucoma pathogenesis. However, the relationships between SAS, high systemic oxidative stress and the speed of glaucoma progression are unclear. Thus, we investigated these relationships in glaucoma patients with and without SAS. METHODS: Peripheral blood samples were collected from 166 eyes of 166 Japanese patients: 42 controls, 109 open-angle glaucoma (OAG) patients without SAS and 15 OAG patients with SAS...
March 2, 2018: Acta Ophthalmologica
Şenay Aydin, Cengiz Özdemir, Cem Ismail Küçükali, Sinem Nedime Sökücü, Murat Giriş, Uğur Akcan, Erdem Tüzün
BACKGROUND/AIM: Obstructive sleep apnea syndrome (OSAS) is associated with intermittent episodes of hypoxia, endothelial dysfunction and associated cardiovascular problems. Our aim was to investigate whether OSAS-related hypoxia alters the expression of rho-associated protein kinase (ROCK), a marker of chronic hypoxia and endothelial dysfunction. MATERIALS AND METHODS: ROCK1 and ROCK2 levels were measured by immunoblotting in peripheral blood mononuclear cells (PBMC) of 47 OSAS patients and 17 healthy controls...
March 2018: In Vivo
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"