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https://www.readbyqxmd.com/read/29679819/submarine-groundwater-discharge-and-chemical-behavior-of-tracers-in-laizhou-bay-china
#1
Yan Zhang, Hailong Li, Xuejing Wang, Chaoyue Wang, Kai Xiao, Wenjing Qu
Naturally occurring radon (222 Rn) and radium isotopes are widely used to trace water mixing and submarine groundwater discharge (SGD) in the coastal zones. However, their activities in groundwater are variable both spatially and temporally. Here, time series sampling of 222 Rn and radium was conducted to investigate their behavior in intertidal groundwater of Laizhou Bay, China. The result shows that groundwater redox conditions have an important impact on the behavior of tracers. The activities of tracers will decrease under oxidizing conditions and increase under reducing conditions...
April 18, 2018: Journal of Environmental Radioactivity
https://www.readbyqxmd.com/read/29676628/increasing-the-resolution-of-chronic-obstructive-pulmonary-disease-definition-lessons-from-a-cohort-with-remote-but-extensive-exposure-to-secondhand-tobacco-smoke
#2
Mehrdad Arjomandi, Siyang Zeng, Paul D Blanc, Warren M Gold
RATIONALE: The Global Initiative for Chronic Obstructive Lung Disease criteria require a ratio of forced expiratory volume in 1 second (FEV1 ) to forced vital capacity (FVC) (FEV1 /FVC) of less than 0.70 for the diagnosis of chronic obstructive pulmonary disease, whereas other criteria emphasize a lower limit of normal approach. However, the use of Global Initiative for Chronic Obstructive Lung Disease (or lower limit of normal) criteria may result in classification of many smokers with respiratory morbidities as not having chronic obstructive pulmonary disease...
April 2018: Annals of the American Thoracic Society
https://www.readbyqxmd.com/read/29674430/rapid-sea-level-rise-in-the-aftermath-of-a-neoproterozoic-snowball-earth
#3
P M Myrow, M P Lamb, R C Ewing
Earth's most severe climate changes occurred during global-scale snowball-Earth glaciations, which profoundly altered Earth's atmosphere, oceans, and biosphere. Extreme rates of glacio-eustatic sea-level rise are a fundamental prediction of the snowball Earth hypothesis, but supporting geologic evidence is lacking. We use paleohydraulic analysis of wave ripples and tidal laminae of the Elatina Formation, Australia - deposited following the Marinoan glaciation ca. 635Ma - to show that water depths of 9-16m remained nearly constant for ~100yrs throughout 27m of sediment accumulation...
April 19, 2018: Science
https://www.readbyqxmd.com/read/29670906/desflurane-attenuates-ventilator-induced-lung-injury-in-rats-with-acute-respiratory-distress-syndrome
#4
Xue Lin, Ying-Nan Ju, Wei Gao, Dong-Mei Li, Chang-Chun Guo
Ventilator-induced lung injury aggravates the existing lung injury. This study investigated the effect of desflurane on VILI in a rat model of acute respiratory distress syndrome. Forty-eight rats were randomized into a sham (S) group, control (C) group, lipopolysaccharide/ventilation (LV) group, lipopolysaccharide/ventilation/desflurane (LVD) group, or lipopolysaccharide/low ventilation with and without desflurane (LLV and LLVD) groups. Rats in the S group received anesthesia only. Rats in the LV and LVD groups received lipopolysaccharide and were ventilated with a high tidal volume...
2018: BioMed Research International
https://www.readbyqxmd.com/read/29670537/impact-of-different-tidal-volume-levels-at-low-mechanical-power-on-ventilator-induced-lung-injury-in-rats
#5
Lillian Moraes, Pedro L Silva, Alessandra Thompson, Cintia L Santos, Raquel S Santos, Marcos V S Fernandes, Marcelo M Morales, Vanessa Martins, Vera L Capelozzi, Marcelo G de Abreu, Paolo Pelosi, Patricia R M Rocco
Tidal volume (VT ) has been considered the main determinant of ventilator-induced lung injury (VILI). Recently, experimental studies have suggested that mechanical power transferred from the ventilator to the lungs is the promoter of VILI. We hypothesized that, as long as mechanical power is kept below a safe threshold, high VT should not be injurious. The present study aimed to investigate the impact of different VT levels and respiratory rates (RR) on lung function, diffuse alveolar damage (DAD), alveolar ultrastructure, and expression of genes related to inflammation [interleukin (IL)-6], alveolar stretch (amphiregulin), epithelial [club cell secretory protein (CC)16] and endothelial [intercellular adhesion molecule (ICAM)-1] cell injury, and extracellular matrix damage [syndecan-1, decorin, and metalloproteinase (MMP)-9] in experimental acute respiratory distress syndrome (ARDS) under low-power mechanical ventilation...
2018: Frontiers in Physiology
https://www.readbyqxmd.com/read/29668325/is-cushing-mechanism-a-dynamic-blood-pressure-stabilizing-system-insights-from-granger-causality-analysis-of-spontaneous-blood-pressure-and-cerebral-blood-flow
#6
Saqib Saleem, Paul D Teal, Connor A Howe, Michael M Tymko, Philip N Ainslie, Yu-Chieh Tzeng
Blood pressure regulation is widely recognised as being integral to the control of end-organ perfusion but it remains unclear whether end-organ perfusion also plays a role in driving changes in blood pressure (BP). A randomized and placebo controlled study design was followed to examine the feedback relationships between very-low-frequency fluctuations in BP and cerebral blood flow (CBF) in humans under placebo treatment and α1-adrenergic blockade. To determine the causal relations among haemodynamic variables, BP, middle cerebral artery blood velocity (MCAv), and end-tidal CO2 time-series were decimated, low-pass filtered (<0...
April 18, 2018: American Journal of Physiology. Regulatory, Integrative and Comparative Physiology
https://www.readbyqxmd.com/read/29666293/fast-or-slow-rescue-ventilations-a-predictive-model-of-gastric-inflation
#7
John R Fitz-Clarke
BACKGROUND: Rescue ventilations are given during respiratory and cardiac arrest. Tidal volume must assure oxygen delivery; however, excessive pressure applied to an unprotected airway can cause gastric inflation, regurgitation, and pulmonary aspiration. The optimal technique provides mouth pressure and breath duration that minimize gastric inflation. It remains unclear if breath delivery should be fast or slow, and how inflation time affects the division of gas flow between the lungs and esophagus...
April 17, 2018: Respiratory Care
https://www.readbyqxmd.com/read/29665427/end-tidal-co-2-guided-automated-robot-cpr-system-in-the-pig-preliminary-communication
#8
Gil Joon Suh, Jaeheung Park, Jung Chan Lee, Sang Hoon Na, Woon Yong Kwon, Kyung Su Kim, Taegyun Kim, Yoon Sun Jung, Jung-In Ko, So Mi Shin, Kyoung Min You
BACKGROUND: Our aim was to compare the efficacy of the end-tidal CO2 -guided automated robot CPR (robot CPR) system with manual CPR and mechanical device CPR. METHODS: We developed the algorithm of the robot CPR system which automatically finds the optimal compression position under the guidance of end-tidal CO2 feedback in swine models of cardiac arrest. Then, 18 pigs after 11 minutes of cardiac arrest were randomly assigned to one of three groups, robot CPR, LUCAS CPR, and manual CPR groups (n = 6 each group)...
April 14, 2018: Resuscitation
https://www.readbyqxmd.com/read/29664963/trpv4-inhibition-attenuates-stretch-induced-inflammatory-cellular-responses-and-lung-barrier-dysfunction-during-mechanical-ventilation
#9
N Pairet, S Mang, G Fois, M Keck, M Kühnbach, J Gindele, M Frick, P Dietl, D J Lamb
Mechanical ventilation is an important tool for supporting critically ill patients but may also exert pathological forces on lung cells leading to Ventilator-Induced Lung Injury (VILI). We hypothesised that inhibition of the force-sensitive transient receptor potential vanilloid (TRPV4) ion channel may attenuate the negative effects of mechanical ventilation. Mechanical stretch increased intracellular Ca2+ influx and induced release of pro-inflammatory cytokines in lung epithelial cells that was partially blocked by about 30% with the selective TRPV4 inhibitor GSK2193874, but nearly completely blocked with the pan-calcium channel blocker ruthenium red, suggesting the involvement of more than one calcium channel in the response to mechanical stress...
2018: PloS One
https://www.readbyqxmd.com/read/29661389/esketamine-counters-opioid-induced-respiratory-depression
#10
K Jonkman, E van Rijnsoever, E Olofsen, L Aarts, E Sarton, M van Velzen, M Niesters, A Dahan
BACKGROUND: Opioids can produce life-threatening respiratory depression. This study tested whether subanaesthetic doses of esketamine stimulate breathing in an established human model of opioid-induced respiratory depression. METHODS: In a study with a randomised, double blind, placebo controlled, crossover design, 12 healthy, young volunteers of either sex received a dose escalating infusion of esketamine (cumulative dose 40 mg infused in 1 h) on top of remifentanil-induced respiratory depression...
May 2018: British Journal of Anaesthesia
https://www.readbyqxmd.com/read/29653187/mid-cervical-spinal-cord-contusion-causes-robust-deficits-in-respiratory-parameters-and-pattern-variability
#11
Philippa M Warren, Cara Campanaro, Frank J Jacono, Warren J Alilain
Mid-cervical spinal cord contusion disrupts both the pathways and motoneurons vital to the activity of inspiratory muscles. The present study was designed to determine if a rat contusion model could result in a measurable deficit to both ventilatory and respiratory motor function under "normal" breathing conditions at acute to chronic stages post trauma. Through whole body plethysmography and electromyography we assessed respiratory output from three days to twelve weeks after a cervical level 3 (C3) contusion...
April 10, 2018: Experimental Neurology
https://www.readbyqxmd.com/read/29649316/effect-of-one-lung-ventilation-on-end-tidal-carbon-dioxide-during-cardiopulmonary-resuscitation-in-a-pig-model-of-cardiac-arrest
#12
Dong Hyun Ryu, Yong Hun Jung, Kyung Woon Jeung, Byung Kook Lee, Young Won Jeong, Jong Geun Yun, Dong Hun Lee, Sung Min Lee, Tag Heo, Yong Il Min
Unrecognized endobronchial intubation frequently occurs after emergency intubation. However, no study has evaluated the effect of one-lung ventilation on end-tidal carbon dioxide (ETCO2) during cardiopulmonary resuscitation (CPR). We compared the hemodynamic parameters, blood gases, and ETCO2 during one-lung ventilation with those during conventional two-lung ventilation in a pig model of CPR, to determine the effect of the former on ETCO2. A randomized crossover study was conducted in 12 pigs intubated with double-lumen endobronchial tube to achieve lung separation...
2018: PloS One
https://www.readbyqxmd.com/read/29644221/physiologic-factors-influencing-the-arterial-to-end-tidal-co-2-difference-and-the-alveolar-dead-space-fraction-in-spontaneously-breathing-anesthetised-horses
#13
Martina Mosing, Stephan H Böhm, Anthea Rasis, Giselle Hoosgood, Ulrike Auer, Gerardo Tusman, Regula Bettschart-Wolfensberger, Johannes P Schramel
The arterial to end-tidal CO2 difference (P(a-ET) CO2 ) and alveolar dead space fraction (VDalvfrac  = P(a-ET) CO2 /PaCO2 ), are used to estimate Enghoff's "pulmonary dead space" (V/QEng ), a factor which is also influenced by venous admixture and other pulmonary perfusion abnormalities and thus is not just a measure of dead space as the name suggests. The aim of this experimental study was to evaluate which factors influence these CO2 indices in anesthetized spontaneously breathing horses. Six healthy adult horses were anesthetized in dorsal recumbency breathing spontaneously for 3 h...
2018: Frontiers in Veterinary Science
https://www.readbyqxmd.com/read/29629989/an-open-loop-physiologic-model-based-decision-support-system-can-provide-appropriate-ventilator-settings
#14
Dan Stieper Karbing, Savino Spadaro, Nilanjan Dey, Riccardo Ragazzi, Elisabetta Marangoni, Francesca Dalla Corte, Federico Moro, David Lodahl, Niklas Schurmann Hansen, Robert Winding, Stephen Edward Rees, Carlo Alberto Volta
OBJECTIVES: To evaluate the physiologic effects of applying advice on mechanical ventilation by an open-loop, physiologic model-based clinical decision support system. DESIGN: Prospective, observational study. SETTING: University and Regional Hospitals' ICUs. PATIENTS: Varied adult ICU population. INTERVENTIONS: Advice were applied if accepted by physicians for a period of up to 4-8 hours. MEASUREMENTS AND MAIN RESULTS: Seventy-two patients were included for data analysis...
April 6, 2018: Critical Care Medicine
https://www.readbyqxmd.com/read/29625596/comparative-bench-study-evaluation-of-different-infant-interfaces-for-non-invasive-ventilation
#15
Giorgio Conti, Giorgia Spinazzola, Cesare Gregoretti, Giuliano Ferrone, Andrea Cortegiani, Olimpia Festa, Marco Piastra, Luca Tortorolo, Roberta Costa
BACKGROUND: To compare, in terms of patient-ventilator interaction and performance, a new nasal mask (Respireo, AirLiquide, FR) with the Endotracheal tube (ET) and a commonly used nasal mask (FPM, Fisher and Paykel, NZ) for delivering Pressure Support Ventilation (PSV) in an infant model of Acute Respiratory Failure (ARF). METHODS: An active test lung (ASL 5000) connected to an infant mannequin through 3 different interfaces (Respireo, ET and FPM), was ventilated with a standard ICU ventilator set in PSV...
April 7, 2018: BMC Pulmonary Medicine
https://www.readbyqxmd.com/read/29625576/skeletal-cardiac-and-respiratory-muscle-function-and-histopathology-in-the-p448lneo-mouse-model-of-fkrp-deficient-muscular-dystrophy
#16
Qing Yu, Melissa Morales, Ning Li, Alexander G Fritz, Ren Ruobing, Anthony Blaeser, Ershia Francois, Qi-Long Lu, Kanneboyina Nagaraju, Christopher F Spurney
BACKGROUND: Fukutin-related protein (FKRP) mutations are the most common cause of dystroglycanopathies known to cause both limb girdle and congenital muscular dystrophy. The P448Lneo- mouse model has a knock-in mutation in the FKRP gene and develops skeletal, respiratory, and cardiac muscle disease. METHODS: We studied the natural history of the P448Lneo- mouse model over 9 months and the effects of twice weekly treadmill running. Forelimb and hindlimb grip strength (Columbus Instruments) and overall activity (Omnitech Electronics) assessed skeletal muscle function...
April 6, 2018: Skeletal Muscle
https://www.readbyqxmd.com/read/29605203/in-vitro-and-clinical-characterization-of-the-valved-holding-chamber-aerochamber-plus-%C3%A2-flow-vu-%C3%A2-for-administrating-tiotropium-respimat-%C3%A2-in-1-5-year-old-children-with-persistent-asthmatic-symptoms
#17
Herbert Wachtel, Mark Nagel, Michael Engel, Georges El Azzi, Ashish Sharma, Jason Suggett
BACKGROUND: When characterizing inhalation products, a comprehensive assessment including in vitro, pharmacokinetic (PK), and clinical data is required. We conducted a characterization of tiotropium Respimat® when administered with AeroChamber Plus® Flow-Vu® anti-static valved holding chamber (test VHC) with face mask in 1-5-year-olds with persistent asthmatic symptoms. METHODS: In vitro tiotropium dose and particle size distribution delivered into a cascade impactor were evaluated under fixed paediatric and adult flow rates between actuation and samplings...
April 2018: Respiratory Medicine
https://www.readbyqxmd.com/read/29600057/neutrophil-to-lymphocyte-ratio-as-a-prognostic-marker-in-acute-respiratory-distress-syndrome-patients-a-retrospective-study
#18
Ying Wang, Mohan Ju, Cuicui Chen, Dong Yang, Dongni Hou, Xinjun Tang, Xiaodan Zhu, Donghui Zhang, Lilin Wang, Shimeng Ji, Jinjun Jiang, Yuanlin Song
Background: Acute respiratory distress syndrome (ARDS) is the leading cause of high mortality in intensive care units (ICUs) worldwide. An effective marker for prognosis in ARDS is particularly important given the absence of effective treatment strategies aside from small tidal volume ventilation. Previous studies identified an association between the neutrophil-to-lymphocyte ratio (NLR) and prognosis in critical patients. In this study, we explored the prognostic and predictive value of the NLR in ARDS patients...
January 2018: Journal of Thoracic Disease
https://www.readbyqxmd.com/read/29593507/the-times-of-our-lives-interaction-among-different-biological-periodicities
#19
Rodrigo Laje, Patricia V Agostino, Diego A Golombek
Environmental cycles on Earth display different periodicities, including daily, tidal or annual time scales. Virtually all living organisms have developed temporal mechanisms to adapt to such changes in environmental conditions. These biological timing structures-ranging from microsecond to seasonal timing-may have intrinsic properties and even different clock machinery. However, interaction among these temporal systems may present evolutionary advantages, for example, when species are exposed to changing climatic conditions or different geographic locations...
2018: Frontiers in Integrative Neuroscience
https://www.readbyqxmd.com/read/29580876/regulatory-respiratory-data-refinement-with-reduced-animal-usage
#20
Louise Sladen, Rommel Matheson, Kevin Norton, Aileen Milne
INTRODUCTION: Assessment of effects of potential drug candidates on the respiratory system is part of the regulatory preclinical safety assessment conducted prior to first in human trials (FTIH). Commonly, this is carried out utilizing head out plethysmography (HOP) or whole body plethysmography (WBP) which record only ventilatory parameters. When dosing via the inhaled route a more thorough respiratory assessment, including a direct measure of airway mechanics, is desirable. The aim of the present work was to improve the strategy for respiratory safety testing by a) evaluating a telemetered pleural pressure - HOP (PP-HOP) model and b) evaluating a crossover study design protocol in the WBP model to reduce variability and animal usage...
March 23, 2018: Journal of Pharmacological and Toxicological Methods
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