Search results for "Respiration"
showing 10 items of 538 documents
Non-uniform multivariate embedding to assess the information transfer in cardiovascular and cardiorespiratory variability series
2012
The complexity of the short-term cardiovascular control prompts for the introduction of multivariate (MV) nonlinear time series analysis methods to assess directional interactions reflecting the underlying regulatory mechanisms. This study introduces a new approach for the detection of nonlinear Granger causality in MV time series, based on embedding the series by a sequential, non-uniform procedure, and on estimating the information flow from one series to another by means of the corrected conditional entropy. The approach is validated on short realizations of linear stochastic and nonlinear deterministic processes, and then evaluated on heart period, systolic arterial pressure and respira…
Progressive active mobilization with dose control and training load in critically ill patients (PROMOB): Protocol for a randomized controlled trial
2020
The dose of progressive active mobilization is still uncertain. The purpose of this study is to identify if the addition of a protocol of progressive active mobilization with dose and training load control to usual care is effective in reducing the length of stay in intensive care unit (ICU) and the improvement of the functioning, incidence of ICU-acquired weakness (ICUAW), mechanical ventilation duration and mortality rate in patients hospitalized in ICU. It is Double-blind randomised clinical trial. The setting for this trial will be medical and surgical ICU of a university hospital. The study participants will be 118 patients aged> 18 years admitted to ICU for less than 72 hours. Partici…
Surrogate Data Analysis for Assessing the Significance of the Coherence Function
2004
In cardiovascular variability analysis, the significance of the coupling between two time series is commonly assessed by setting a threshold level in the coherence function. While traditionally used statistical tests consider only the parameters of the adopted estimator, the required zero-coherence level may be affected by some features of the observed series. In this study, three procedures, based on the generation of surrogate series sharing given properties with the original but being structurally uncoupled, were considered: independent identically distributed (IID), Fourier transform (FT), and autoregressive (AR). IID surrogates maintained the distribution of the original series, while …
Ethanol cycle in an ethanologenic bacterium
2002
AbstractA novel redox cycle is suggested, performing interconversion between acetaldehyde and ethanol in aerobically growing ethanologenic bacterium Zymomonas mobilis. It is formed by the two alcohol dehydrogenase (ADH) isoenzymes simultaneously catalyzing opposite reactions. ADH I is catalyzing acetaldehyde reduction. The local reactant ratio at its active site probably is shifted towards ethanol synthesis due to direct channeling of NADH from glycolysis. ADH II is oxidizing ethanol. The net result of the cycle operation is NADH shuttling from glycolysis to the membrane respiratory chain, and ensuring flexible distribution of reducing equivalents between the ADH reaction and respiration.
Relationship between rhinitis duration and worsening of nasal function
2008
BackgroundWhile it is well known that asthma is characterized by airway remodeling, few studies instead have investigated this issue in patients with allergic rhinitis (AR).ObjectiveThe aim of the study was to evaluate nasal function, ie, nasal airflow, in a cohort of patients with persistent AR (PER).MethodsOne hundred patients, 50 with short-term and 50 with long-term PER, were prospectively and consecutively evaluated, clinically evaluated by visit, skin prick test, and rhinomanometry.ResultsNasal airflow values were significantly lower (median flow: 348 mL/sec) in patients with long-term rhinitis (median duration nine years) as compared to patients with short-term (median duration one y…
Radiofrequency volumetric tissue reduction (RFVTR) of inferior turbinates: a new method in the treatment of chronic nasal obstruction.
2001
Twenty-two Caucasians (16 male and 6 female) with chronic bilateral nasal obstruction due to hypertrophic inferior turbinates were followed up over a three-month period. They were assessed by clinical examination, as active anterior rhinometry, and acoustic rhinometry before and after topical decongestion, preoperatively and three months after surgery. All patients were treated by application of radiofrequency-volumetric-tissue reduction (RFVTR, or somnoplasty) to both inferior turbinates. Initial postoperative edematous response disappeared during the first week after RFVTR. Three months postoperatively 20 of 22 patients (91%) reported subjective improvement of nasal patency. The average …
Respiratory proteins in Sipunculus nudus--implications for phylogeny and evolution of the hemerythrin family.
2009
Three major classes of respiratory proteins are known, hemoglobin, molluscan and arthropod hemocyanin, and hemerythrin (Hr). Similar to hemoglobin, respiratory Hr is packed into erythrocytes floating in the coelomic fluid and is only known from sipunculids, brachiopods, and priapulids. Owing to this scattered distribution, the presence of Hr is generally assumed to be the plesiomorphic condition without phylogenetic importance. By sequencing 2000 Expressed Sequence Tags (ESTs) from Sipunculus nudus, we found 75 Hr-coding ESTs assembled to 20 cDNA contigs classified as four distinct Hr isoforms: three polymeric Hrs (subunit A, A', and B) and the monomeric myo-hemerythrin (myoHr). Phylogeneti…
Pathogenesis of circulatory reactions triggered by nervous reflexes during the implantation of bone cements.
1983
Circulatory and respiratory reactions during the implantation of joint endoprostheses have been observed for years. The components of the bone cements used for anchoring (methyl methacrylate monomer) or the outpour of bone marrow substances from the affected bone marrow cavity are thought to be chiefly responsible for these effects. However, our previous investigations demonstrated unambiguously that reactions of this type can be attributed to direct nervous-reflex mechanisms triggered by the pressure rise in the medullary canal, and that, in addition, bone marrow embolism plays a part in serious circulatory incidents. The investigations on which the present paper is based have confirmed th…
Neuroglobin: A Respiratory Protein of the Nervous System
2004
Nerve tissues exhibit some of the highest oxygen consumption rates found in the body. Neuroglobin, a heme protein distantly related to hemoglobin, is thought to enhance the supply of oxygen to the neurons, the eye, and some endocrine tissues. Neuroglobin may promote neuronal survival under hypoxic conditions as they occur, for example, in stroke.
Cycle-triggered averaging of respiration-related neuronal activity
1985
Abstract A computer system is presented which provides off-line computation of cycle-triggered histograms (CTH) of respiration-related neuronal activity. Binwidths of the histograms are freely selectable by software from 10 ms to 100 ms. For special evaluation purposes. CTHs can be standardized in different ways concerning cycle duration as well as amplitude. Time incidence of maximum frequency, center of gravity and expiration-to-inspiration phase transition within the respiratory cycle are computed. The system employs special hardware interfaces to an 8-bit microcomputer which are briefly described. Data acquisition, data manipulation and output handling of the results are performed by ch…