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See detailInfluence of Back Mixing on the Convective Drying of Residual Sludges in a Fixed Bed
Léonard, Angélique ULg; Meneses, Eustedio; Le Trong, Emmanuel et al

in Water Research (2008), 42(10-11), 2671-2677

The influence of a backmixing operation on the convective belt drying of two wastewater sludges was studied. The expansion of the sludge extrudates bed due to increasing additions of dry product was ... [more ▼]

The influence of a backmixing operation on the convective belt drying of two wastewater sludges was studied. The expansion of the sludge extrudates bed due to increasing additions of dry product was quantified by using X-ray tomography. This non-invasive technique was used to determine the bed porosity and the total exchange area available for heat and mass transfers, for increasing levels of backmixing. For a same drying flux, the expansion of the drying bed leads to higher drying rates, allowing a reduction of the total drying time. In this context, rheological properties of the sludges are key properties. [less ▲]

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See detailInfluence of back school and physical exercises on pain-related fears
Demoulin, Christophe ULg; Gagnol, Aude; GROSDENT, Stéphanie ULg et al

in Vleeming, Andry; Fitzgerald, Colleen (Eds.) 7th Interdisciplinary World Congress on Low Back & Pelvic Pain - Effective diagnosis and treatment of lumbopelvic pain (2010, November)

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See detailInfluence of baseline patient characteristics on response to one-monthly and daily oral ibandronate therapy: 2-year findings from MOBILE
Reginster, Jean-Yves ULg; Hawker, G.; Bolognese, M. et al

in Annals of the Rheumatic Diseases (2006, June), 65(Suppl.II), 426

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See detailInfluence of basement membrane molecules on directional migration of human breast cell lines in vitro.
Coopman, P. J.; Bracke, M. E.; Lissitzky, J. C. et al

in Journal of Cell Science (1991), 98(Pt 3), 395-401

Spheroidal cell aggregates were prepared from four tumorigenic human breast cell lines (HBL-100 and three MCF-7 variants). Cells from these aggregates were allowed to migrate towards lanes of basement ... [more ▼]

Spheroidal cell aggregates were prepared from four tumorigenic human breast cell lines (HBL-100 and three MCF-7 variants). Cells from these aggregates were allowed to migrate towards lanes of basement membrane components coated on a glass substratum. Matrigel (reconstituted basement membrane) lanes permanently arrested the migration of one MCF-7 cell line, while migration of the others was permitted. Amongst several purified basement membrane constituents only laminin, not collagen type IV or fibronectin, was found to cause the same arrest of migration. Within the laminin molecule only the pepsin P1, not the elastase E8 fragment, efficiently arrested migration of that cell line. Although migration was inhibited by these components, time-lapse video recordings revealed that arrested cells still proliferated and actively ruffled on top of the coatings. These data suggest that, amongst several basement membrane components, laminin can function as a stop signal for cell migration. Within laminin, this activity seems to be mainly associated with the P1 fragment. We conclude that laminin is the major determinant of the barrier-function of the basement membrane, to which some cell types have become insensitive. [less ▲]

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See detailInfluence of behavioral states on cerebral blood flow velocity patterns in preterm infants
RAMAEKERS, Vincent ULg; Casaer, P.

in The Journal of pediatrics (1987), 111(5), 795

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See detailThe influence of behavioural states on cerebral blood flow velocity patterns in stable preterm infants.
RAMAEKERS, Vincent ULg; Casaer, P.; Daniels, H. et al

in Early human development (1989), 20(3-4), 229-46

Previous Doppler ultrasound studies assessing cerebral blood flow velocities in the anterior cerebral artery (ACA) among healthy term and preterm infants, showed a widespread range for the calculated flow ... [more ▼]

Previous Doppler ultrasound studies assessing cerebral blood flow velocities in the anterior cerebral artery (ACA) among healthy term and preterm infants, showed a widespread range for the calculated flow indices. However, only one of these studies accounted for the infant's behavioural state. In the present study a stable pattern of the cerebral blood flow velocity tracings and of the Pulsatility Index (PI) was observed during state 1, whereas marked fluctuations in cerebral blood flow velocity and PI were found during state 4 or active wakefulness. During state 2, minor variations of cerebral blood flow velocity and PI occurred though tended to be less pronounced than during active wakefulness. Thus at the time of Doppler assessment the cerebral blood flow velocity pattern and its variability will be better understood by taking into account the behavioural state of the infant. [less ▲]

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See detailInfluence of bench press exercise modality on the iso-inertial performance
Jidovtseff, Boris ULg; Croisier, Jean-Louis ULg; Crielaard, Jean-Michel ULg

in Science & Sports (2006), 21(3), 159-162

Introduction. - This study used an iso-inertial dynamometer to investigate the influence of counter-movement and barbell throwing during bench press exercise. A critical analysis of these modalities ... [more ▼]

Introduction. - This study used an iso-inertial dynamometer to investigate the influence of counter-movement and barbell throwing during bench press exercise. A critical analysis of these modalities during muscular evaluation was also performed. Methods. - The action of muscle stretch during the counter-movement induced an increase in average velocity and a shortening of the time to reach the peak power and peak velocity. The barbell throwing did not alter the initial part of the movement yet lengthened the propulsive phase and delayed the braking phase. Consequently, maximal power and maximal velocity performances were improved. However, the throwing of the barbell requires its catch when failing down, which could be potentially harmful. Conclusion. - The counter-movement and the throwing of the barbell significantly change the iso-inertial performances through a bench press exercise. The modalities of bench press assessment execution would have to be rigorously standardized. (c) 2006 Elsevier SAS. Tous droits reserves. [less ▲]

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See detailThe influence of biogeochemical processes on the pH dynamics in the seasonally hypoxic saline Lake Grevelingen
Hagens, M; Slomp, C; Meysman, F et al

Poster (2013, April 07)

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See detailThe influence of biogeochemical processes on the pH dynamics in the seasonally hypoxic saline Lake Grevelingen, The Netherlands
Hagens, M; Slomp, C; Meysman, F et al

Poster (2013, May 07)

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See detailInfluence of Biomaterials in Alveolar Bone Regeneration and Preservation
LAMBERT, France ULg

Doctoral thesis (2011)

Dental implants are nowadays a reliable solution to replace missing teeth and have been widely documented. However, they require a minimal bone quantity (in height and thickness). But alveolar bone ... [more ▼]

Dental implants are nowadays a reliable solution to replace missing teeth and have been widely documented. However, they require a minimal bone quantity (in height and thickness). But alveolar bone defects are very frequent, for instance due to periodontitis, traumatism or acute dental infection. Moreover, a simple tooth extraction leads to significant bone resorption. Therefore, alveolar bone regeneration is often necessary in order to place implants and to restore the patient's dentition with implant-supported prosthesis. Even though alveolar bone reconstructions have been considered as traumatic, especially due to the need of a second surgical site for bone harvesting, techniques have evolved with the introduction of biomaterials. However, it is difficult to compare the influences of such biomaterials on osteogenesis and to elaborate on the advantages of one product over another. The overall objective of this thesis is to contribute to the understanding of the biological concept of alveolar bone regeneration, in particular sinus lift and socket preservation procedures. The influence of biomaterials on bone regeneration has been emphasized through preclinical and clinical studies. The number of commercially available biomaterials for bone regeneration is growing every day and some materials are not supported by strong scientific data in the literature. The first part of this thesis (Chapter 1) is dedicated to the characterization of several biomaterials often used in dentistry. The impact of their various characteristics on osteogenesis has been reviewed, from chemical aspect to micro- and macromorphology. Furthermore, a data sheet integrating the physico-chemical and morphological properties of each studied biomaterial has been developed as a tool for clinicians. Sinus floor elevation has often been considered as a bone graft. In 1996, a consensus conference on “sinus lift” took place and the procedure was qualified as “sinus bone-graft”. But new scientific evidence has shown that this qualification is not justified. Chapter 2 aims at understanding the physiology and the biological model of sub-sinusal bone augmentation by using either a simple blood clot, autogenous bone chips or biomaterials (BHA) as space fillers under the lifted sinusal membrane. If bone formation did occur with the 3 types of space fillers, the augmented volumes significantly dropped with the blood clot or the autogenous bone chips but remained stable with BHA. Therefore, a slowly resorbable biomaterial such as BHA might be suitable in sub-sinusal bone augmentation to prevent the re-expansion process. Understanding the biological concept of sinus lift procedures, several authors demonstrated the clinical efficacy of biomaterials when used alone in this specific model. Nevertheless, biomaterials known to be resorbable led to a lamellar bone architecture that might not be able to maintain the volume of the regenerated tissue over time. Moreover, many types of biomaterials are available and scientific evidence of short and long-term performance of newly introduced biomaterials is still poor. Chapter 3 aims at comparing the performances, in terms of bone formation, resorption rate and 3-D stability, of four calcium phosphate-based biomaterials often used for sub-sinusal bone augmentation, in a rabbit model. Particulated space-filling biomaterials seemed to be more efficient to promote osteogenesis compared to paste-like biomaterials. Highly resorbable biomaterials appeared to withstand intrasinusal pressure after a period of six months in rabbits. Non- or slowly resorbable biomaterials are of great interest in the dental field because the long-term stability of 3-D bone augmentation is a key factor for dental implant and aesthetic outcomes. Therefore, the mechanical and non-resorbable properties of titanium, known to be highly compatible in vivo and highly resistant to body fluid corrosion, are potential advantages for bone augmentation prior to dental implantation. Nevertheless, the use of titanium particles as space fillers in bone regeneration was weakly reported in the literature from a histological point of view. Thus, Chapter 4 compares the behavior and the effect of porous titanium particles versus the well-documented BHA. Even though both biomaterials allowed osteogenesis and adequate 3-D stability, the bone architecture, and more specifically the amount of bone-to-material contact (BMC), was significantly different. Inclusion of the particles in a carrier or in binding agents such as a collagen gel or fibers might be of interest in order to ease surgical handling. However, the possible influence of those collagen carriers on bone tissue responses remains poorly investigated. The objective of Chapter 5 was to investigate the effect of collagen at different stages of the osteogenesis process, still in the same rabbit model. The findings clearly showed the presence of inflammatory cells at an early stage of bone regeneration when collagenated xenogenic biomaterials were used compared to collagen-free xenogenic granules. Nevertheless, despite the transient inflammation, the final quantity of newly formed bone was similar in the various groups. The last two chapters of this thesis take some of the preclinical findings of the previous chapters to the clinical field. The objective of Chapter 6 was to assess the clinical outcome of a minimalized sub-sinusal bone augmentation procedure using only biomaterials, simultaneously with the placement of 102 non-submerged implants in 40 patients. Implant and prosthodontic survival rates as well as complications were evaluated after a follow-up period of 2 to 6 years. This clinical trial emphasized that, if the amount of remaining bone height is sufficient to ensure implant primary stability, their placement can be performed simultaneously with sinus lifting, even in a non-submerged fashion. This procedure reduces the number of surgeries and the time before prosthetic rehabilitation. The objective of Chapter 7 was to to develop a new method to objectively evaluate in humans the 3-D volume variation of alveolar socket preservation over time by means of computed tomography and 3-D image analysis. Short summary: Before placing dental implants, alveolar bone regeneration is often required due to bone defects caused by periodontitis, traumatism or even a simple tooth extraction. Bone augmentation surgical procedures have very much evolved thanks to a better understanding of biological processes and to the introduction of biomaterials. The overall objective of this thesis is to bring a contribution to the understanding of the biological concept of alveolar bone regeneration, and in particular sinus lift and socket preservation procedures. The influence of biomaterials on bone regeneration has been emphasized through preclinical and clinical studies. [less ▲]

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See detail"Influence of bioreactor aeration conditions on sporulation rate of Bacillus subtilis (b 213 stream)"
Meurisse, E.; Hbid, Ch.; Jacques, Ph. et al

in Mededelingen - Faculteit Landbouwwetenschappen, Rijksuniversiteit Gent (1993), 58(4b), 1985-1987

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See detailInfluence of bioreactor hydraulic characteristics on a Saccharomyces cerevisiae fed-batch culture: hydrodynamic modelling and scale-down investigations.
Lejeune, Annick ULg; Delvigne, Frank ULg; Thonart, Philippe ULg

in Journal of Industrial Microbiology & Biotechnology (2010), 37

Yeast is a widely used microorganism at the industrial level because of its biomass and metabolite production capabilities. However, due to its sensitivity to the glucose effect, problems occur during ... [more ▼]

Yeast is a widely used microorganism at the industrial level because of its biomass and metabolite production capabilities. However, due to its sensitivity to the glucose effect, problems occur during scale-up to the industrial scale. Hydrodynamic conditions are not ideal in large-scale bioreactors, and glucose concentration gradients can arise when these bioreactors are operating in fed-batch mode. We have studied the effects of such gradients in a scale-down reactor, which consists of a mixed part linked to a non-mixed part by a recirculation pump, in order to mimic the hydrodynamic conditions encountered at the large scale. During the fermentation tests in the scale-down reactor, there was a drop in both biomass yield (ratio between the biomass produced and the glucose added) and trehalose production and an increase in both fermentation time (time between inoculation and beginning of stationary phase) and ethanol production. We have developed a stochastic model which explains these effects as the result of an induction process determined mainly by the hydrodynamic conditions. The concentration profiles experienced by the microorganisms during the scale-down tests were expressed and linked to the biomass yields of the scale-down tests. [less ▲]

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See detailInfluence of blanching on the quality of Brussels sprouts (Brassica oleracea L cv gemmifera).
Wathelet, Jean-Paul ULg; Mabon, N.; Foucart, M. et al

in Sciences des Aliments (1996), 16(4), 393-402

Blanching of Brussels sprouts before freezing induces chemical, enzymatical and physico-chemical modifications. This blanching study was made at three temperatures (in water at 90 degrees C and 95 degrees ... [more ▼]

Blanching of Brussels sprouts before freezing induces chemical, enzymatical and physico-chemical modifications. This blanching study was made at three temperatures (in water at 90 degrees C and 95 degrees C, in steam at 105 degrees C), The glucosinolate and glucose contents decrease when the technological treatment is extended. These losses are higher in water blanching, especially for external leaves, The myrosinase activity is reduced when treatment time and temperature increase. The peroxydase which is more thermoresistant than myrosinase is a good test for measuring inactivation of enzymes during the industrial blanching. Variations of the colour (green) are larger for external leaves than in the middle of the material. After two minutes of blanching, a hardening of Brussels sprouts is observed hut, after that time, the hardness decreases. [less ▲]

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See detailThe Influence of Blends on the Potential of Extrasolar Planets Transit Surveys
Gillon, Michaël ULg; Magain, Pierre ULg; Guillot, T. et al

in Protostars and Planets V (2005)

Due to their low geometric probability, planetary transits are rare, and photometric surveys searching for such events have to observe many stars at once and, thus, deal with rather crowded fields. This ... [more ▼]

Due to their low geometric probability, planetary transits are rare, and photometric surveys searching for such events have to observe many stars at once and, thus, deal with rather crowded fields. This crowding has two negative effects on the final results of the survey: it decreases the number of detectable transits and increases the number of false positives. We have studied the influence of crowding on different surveys (existing ones as well as planned or even fictitious ones). On the basis of simple but realistic assumptions about the fraction of lower main sequence stars harboring telluric and giant planets within the outer limit of their habitable zone, we predict the harvests of several surveys with and without taking into account the losses due to blends. Our results show that deep surveys such as OGLE-III are much more affected by blends than wide field surveys. Space missions such as Corot and Kepler, although they use very broad PSFs in order to increase the S/N, loose a much lower fraction of transits than deep ground-based surveys. We have also estimated the proportion of false positives in the harvest of the surveys. Thus, our results provide a reliable comparison between the considered surveys. [less ▲]

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See detailInfluence of blood glucose control on the progression of cardiac autonomic neuropathy in Type 1 diabetes.
PHILIPS, Jean-Christophe ULg; MARCHAND, Monique ULg; Geronooz, I. et al

in Diabetologia (2004), 47(suppl 1), 368-3691029

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See detailThe influence of blood transfusion on brain blood flow autoregulation among stable preterm infants.
RAMAEKERS, Vincent ULg; Casaer, P.; Daniels, H. et al

in Early human development (1992), 30(3), 211-20

Prior to and 24 h following blood transfusion serial determinations of both cerebral artery flow velocity waveforms and mean arterial blood pressure have been used to reconstruct the autoregulatory curve ... [more ▼]

Prior to and 24 h following blood transfusion serial determinations of both cerebral artery flow velocity waveforms and mean arterial blood pressure have been used to reconstruct the autoregulatory curve and its upper blood pressure limit among five stable preterm infants. Prior to transfusion the autoregulatory range of cerebral blood flow (CBF) was narrow due to a relatively low-set upper blood pressure limit. At 24 h after transfusion each individual has been re-examined. Following correction of anemia both a significant reduction of CBF velocities as well as a concomitant rise of the Pulsatility Index (PI) occurred over the entire range of blood pressures indicating a reduction of CBF after transfusion. In addition a right-sided shift of the upper limit towards higher mean blood pressures occurred after transfusion and resulted in an extension of the autoregulatory plateau of CBF. These favourable effects of blood transfusion ameliorating autoregulation of brain blood flow particularly at higher blood pressures might well bear important therapeutic perspectives in our effort to prevent intracranial haemorrhage among sick preterm infants. [less ▲]

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See detailInfluence of body size on tibial nerve somato sensory evoked potentials in dogs
Poncelet, Luc; Michaux, Charles; Balligand, Marc ULg

in American Journal of Veterinary Research (1993)

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See detailInfluence of brain-derived neurotrophic factor val66met human polymorphism on declarative memory consolidation
Mascetti, Laura ULg; Foret, Ariane ULg; Matarazzo, Luca et al

Poster (2010, November 15)

The Brain-Derived Neurotrophic Factor (BDNF) is a neurotrophin which in the adult brain regulates long-term potentiation. In humans, valine (val) to methionine (met) substitution in the 5’ pro-region of ... [more ▼]

The Brain-Derived Neurotrophic Factor (BDNF) is a neurotrophin which in the adult brain regulates long-term potentiation. In humans, valine (val) to methionine (met) substitution in the 5’ pro-region of the BDNF protein is associated with poorer episodic memory. Neurons transfected with met-BDNF-Green Fluorescence Protein showed lower depolarization-induced secretion, while constitutive secretion is unchanged. Here, we hypothesized that the differences in BDNF release determined by this polymorphism would influence memory consolidation and that in comparison with the val/met (=val/met or met/met), val/val individuals would show higher memory performance and different brain responses during a 16h-delayed rather than immediate retrieval session. Participants encoded a series of neutral faces in the afternoon. Retrieval sessions took place one hour after the encoding session, and in the following morning, during the acquisition of functional Magnetic Resonance Imaging (fMRI) time series with a 3 Tesla Allegra scanner. During retrieval, studied faces and new ones were presented in random order. For each stimulus, the subjects indicated whether they could retrieve the encoding episode with (“Remember”), or without details (“Know”), or if they thought the item had not been presented during encoding (“New”). A repeated-measure ANOVA on discrimination index (d’) showed significant effects of group (F(1, 27)=8.65, p=0.007, n(val/val)=14, n(val/met)=15) and session (F(1, 27)=24.64, p=0.000), although the group by session interaction was not significant (F(1, 27)=1.29, p=0.267). fMRI results showed a significant genotype (val/val > val/met) by session (delayed > immediate retrieval) by memory type (Remember > Know) interaction in the right inferior occipital gyrus (x=42, y=-78, z=0, p=0.004, Z=3.77), the left inferior parietal lobule (x=-56, y=-40, z=48, p=0.013, Z=3.43), the posterior cingulate cortex (x=14, y=-42, z=42, p=0.019, Z=3.29) and the right hippocampus (x=28, y=-22, z=-22, p=0.03, Z=3.11). Val/val individuals demonstrate higher memory performance than met-carriers but the change in memory performance between immediate and delayed retests is similar in both allelic groups. In contrast, neural correlates of recollection change between sessions differently according to genotype: responses increase significantly more in val/val than in val/met individuals in brain areas involved in the retrieval, accumulation and binding of perceptual memory details during delayed, relative to immediate retest. These data suggest that activity-dependent BDNF release promotes memory consolidation during the first post-training hours. [less ▲]

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See detailInfluence of Brain-Derived Neurotrophic Factor val66met human polymorphism on declarative memory consolidation during sleep
Mascetti, Laura ULg; Foret, Ariane ULg; Matarazzo, Luca et al

Poster (2010, September 15)

Objectives The Brain-Derived Neurotrophic Factor (BDNF) is a neurotrophin which in the adult brain, regulates long-term potentiation and has been involved in the build up of the homeostatic sleep pressure ... [more ▼]

Objectives The Brain-Derived Neurotrophic Factor (BDNF) is a neurotrophin which in the adult brain, regulates long-term potentiation and has been involved in the build up of the homeostatic sleep pressure in rodents. In humans, valine (val) to methionine (met) substitution in the 5’ pro-region of the BDNF protein is associated with poorer episodic memory. Neurons transfected with met-BDNF-Green Fluorescence Protein showed lower depolarization-induced secretion, while constitutive secretion is unchanged. Here, we hypothesized that the differences in BDNF release determined by this polymorphism would influence sleep-dependent memory consolidation and that in comparison with the met-carriers (val/met or met/met), val/val individuals would show higher memory performance after one night of sleep rather than an immediate retrieval session. Methods Participants encoded a series of neutral faces in the afternoon. Retrieval sessions took place one hour after the encoding session, and in the following morning, after a night of polysomnographic-monitored sleep. During retrieval, studied faces and new ones were presented in random order. For each stimulus, the subjects indicated whether they could retrieve the encoding episode with (“Remember” response), or without details (“know” response), or if they thought the item had not been presented during encoding (“New” response). Results A repeated-measure ANOVA on discrimination index (d’) showed significant effects of group (F(1, 22)=4.66, p=0.042) and session (F(1, 22)=12.21, df=1, p=0.002). Although the group by session interaction was not significant (F(1, 22)=1.84, p=0.188), exploratory planned comparisons showed that at immediate retrieval, d’ was not significantly different between groups (val/val, d’ = 1.94±0.16; met-carriers, d’= 1.61±0.14; p>0.5). In contrast, during the second retest (the next day) d’ in the val/val group (d’=2.56±0.23) was significantly higher than in the met-carriers group (d’=1.88±0.21; p=0.041). Likewise, a between-session enhancement in d’ was detected only in the val/val population (p=0.003). Conclusion Val/val individuals demonstrate higher memory performance than met-carriers after a night of sleep but not at immediate retest. These data suggest that activity-dependent BDNF release promotes memory consolidation during the first post-training hours. Further analysis of the present data set will assess the respective effect of sleep and time on the BDNF-associated delayed memory enhancement. This study was supported by FNRS-FRIA, the University of Liège, and the QEMF. [less ▲]

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See detailInfluence of breathing pattern and lung inflation on impulse oscillometry measurements in horses.
Van Erck, Emmanuelle; Votion, Dominique ULg; Kirschvink, Nathalie et al

in Veterinary Journal (2004), 168(3), 259-69

The objective of this paper was to determine if changes in ventilation patterns could influence the outcome of respiratory function measurements performed with our impulse oscillometry system (IOS) in ... [more ▼]

The objective of this paper was to determine if changes in ventilation patterns could influence the outcome of respiratory function measurements performed with our impulse oscillometry system (IOS) in horses. In a first study, IOS tests were performed in vitro on six isolated equine lungs. Lung inflation levels were controlled by modifying depressurisation inside an artificial thorax and different ventilation patterns were imposed. In a second in vivo study, transient variations in breathing pattern were evaluated both with the IOS and a current reference technique (CRT) in five healthy mature horses after an intravenous (i.v.) injection of lobeline hydrochloride. In both studies, respiratory rate (RR, range: 7-42 breaths/min.) and tidal volume (V(T), range: 0.4-25 L) had minor or no influence on IOS parameters. The influence of lung inflation, most marked for resistance at 5 Hz (R(5 Hz)), was limited for the considered physiological range. In vivo, statistical models indicated that maximal changes in pleural pressure (Max Delta Ppl) and peak flows were the main determinants of the variability of the resistance (R(rs)) and the reactance (X(rs)) of the respiratory system. The fourfold increase in baseline Max Delta Ppl and peak flows obtained during hyperpnoea caused a significant increase in R(rs) at 5 and 10 Hz and a decrease in X(rs) at all frequencies. We conclude that IOS parameters are not influenced by tachypnoea, but will reflect alterations in respiratory mechanics caused by hyperpnoeic breathing [less ▲]

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