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1
Acid - base relations between cisternal fluid and arterial blood with reference to control of ventilation
100%
Pokorski M.
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tom 30
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nr 1
2
Changes in acid-base balance and breathing pattern after intracebrally injected ouabain in rabbits
100%
Pokorski M.
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tom 30
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nr 1
3
Content available Zużycie zasobów w cyklu życia konstrukcji: samolot, samochód
100%
Pokorski M.
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2010
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tom Nr 4 (206)
124-135
PL
W pracy przedstawiono analizę zużycia zasobów w cyklu życia konstrukcji, dla samolotu i samochodu, takich jak: energia, materiały, woda. Analiza uwzględnia głównie fazy produkcji i eksploatacji. A także emisję powstających zanieczyszczeń: odpady wyrzucane, ścieki, dwutlenek węgla (CO2) i lotne pochodne węglowodorów (VOC). Wyniki prezentowane są w formie porównania samolotu do samochodu w przeliczeniu na pasażero-kilometr.
EN
The elaboration presents analysis of resources consumption within life cycle for an airplane and a car, such as: energy, materials and water. The analysis takes under account production and operating phases, mainly. Also pollution emission of wastes to landfill, water discharge, Carbon Dioxide (CO2) and Volatile Organic Compounds (VOC). Results are presented as comparison airplane to car recalculated per passenger-kilometer.
4
Efficient management in the construction industry under the current market
100%
Pokorski M.
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tom 126
5
Construction project management in Warsaw. Case study
88%
Pokorski M.
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tom 129
6
The carotid body in the motoneuron response to large inspiration
63%
Jernajczyk U. , Pokorski M.
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nr 5
7
Content available remote Depression and memory: a comparative study of young and old women
63%
Pokorski M. , Siwiec P.
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2008
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tom 59
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nr 6
573-578
8
Content available remote Ventilatory augmentation by acute intermittent hypoxia in the rabbit
63%
Sokolowska B. , Pokorski M.
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nr 4
341-347
EN
This study seeks to determine the effects on respiratory function of acute intermittent hypoxia. The experiments were performed on anesthetized, spontaneously breathing rabbits. The experimental protocol consisted of 5 one-minute episodes of hypoxia (14% O2 in N2) interspersed with three-minute normoxic recovery periods. Ventilatory variables, minute ventilation (MV) and its tidal and frequency components, were derived from the continuously recorded airflow signal. We found that MV progressively increased with each next hypoxic-normoxic cycle; the increases were driven by both ventilatory components. Ventilatory augmentation concerned both the stimulus (hypoxic) and recovery (normoxic) periods, but it was significantly greater in the former. The augmented ventilation was sustained for up to 30 min after the last hypoxic run, which suggests the appearance of ventilatory long-term facilitation. The results demonstrate that acute intermittent hypoxia consisting of a few hypoxic-normoxic cycles is capable of inducing appreciable ventilatory changes. Such changes reflect plasticity of the respiratory motor output developing on a short-term basis during ongoing cycles of hypoxia, which, in the present study, correlated with the number of hypoxic cycle. Ventilatory augmentation in response to acute cyclic hypoxic episodes may give insights into the mechanisms of respiratory improvement by intermittent hypoxic training, increasingly used in both sports physiology and medicinal approaches.
9
Content available remote Oxygen breathing and ventilation
63%
Marczak M. , Pokorski M.
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tom 55
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nr 1,1
EN
We investigated the ventilatory response to normobaric poikilocapnic hyperoxia in healthy subjects. The study was carried out in 26 subjects of the mean age 26 ±0.9 (SE) years, who breathed pure oxygen through a two-way valVE for 10 min. The subjects were in the sitting position with a mouthpiece and nose clip attached. Ventilatory flow was recorded using a pneumotachograph and minute ventilation was calculated from the tidal and frequency components. The SaO2 and alveolar CO2 tension were continuously monitored. Ten of the same subjects constituted a control group in which room air was substituted for oxygen and the tests repeated in the same way at another occasion. We found that oxygen breathing caused a transient 8.4% decline in ventilation, whose nadir was 1 min after the introduction of oxygen. Thereafter, ventilation increased significantly aboVE the baseline value and showed a further rising tendency toward the end of the test. We conclude that acute oxygen treatment is unlikely to haVE a major inhibitory effect on the carotid body-dependent ventilatory driVE in normal subjects. The determinants of the hyperoxic ventilatory stimulation remain to be established in further studies.
10
Involvement of the motor trigeminal nucleus in respiratory phase-switching in the cat
63%
Pokorski M. , Gromysz H.
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nr 1
11
Protein kinase C in the carotid body
63%
Pokorski M. , Faff L.
Acta Neurobiologiae Experimentalis
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1999
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tom 59
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nr 2
12
NADPH-diaphorase in the cat carotid body
63%
Walski M. , Pokorski M.
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nr 1
13
Content available remote Influence of physical activity on psychosomatic health in obese women
51%
Menzyk K. , Cajdler A. , Pokorski M.
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2008
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tom 59
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nr 6
441-448
14
Content available remote Hypoxic ventilatory profile in the anesthetized rat
51%
Marczak M. , Kolesnikova E. E. , Pokorski M.
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nr 3
89-94
EN
In the present study we investigated whether hypocapnia that accompanies hypoxic hyperventilation might affect the biphasic, stimulatory/depressant, ventilatory response to hypoxia. The experiments were carried out in anesthetized, vagotomized, spontaneously breathing, and poikilocapnic rats. The animals were subjected to acute steady-state hypoxia consisting of 12% O2 in N2 in inspiratory mixture. Ventilation and its frequency and volume components were assessed from the integrated electromyographic activity of the diaphragm. We found that despite the development of significant hypocapnia, the hypoxic ventilatory response consisted of rapid stimulation followed by a gradual decline. The frequency component contributed more to the ventilatory increase than that of volume. The results indicate that the hypoxic ventilatory profile in the anesthetized poikilocapnic rat resembles that known to be present during isocapnia. We conclude that hypocapnia neither hampers the hypoxic ventilatory reactivity nor alters the biphasic hypoxic ventilatory profile. These observations may aid planning experimental rat model studies.
15
Content available remote The aging corotid body
51%
Pokorski M. , Walski M. , Dymecka A. , Marczak M.
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nr 3
107-113
EN
The respiratory system is subject to the aging process, which could limit its responsiveness to hyperventilatory stimuli. Attenuation of the ventilatory response to hypoxia in old age is, as yet, an unresolved issue. Such attenuation may be germane for the pathogenesis of respiratory disorders developing more often in elderly subjects. The aim of this study was to determine the potential adverse effects of age on the morphology and function of carotid bodies. Morphology was studied at the level of electron microscopy on carotid bodies dissected from adult young (3 months) and old (>2 years) rats and function by comparing the hypoxic ventilatory response in populations of young (mean age 24 years) and old (mean age 71 years) female subjects. The human protocol consisted of a progressive hypoxia test, based on a rebreathing technique in a closed system. The hypoxic ventilatory response was evaluated from the slopes of minute ventilation on arterial oxygen saturation. The results of the morphological study showed degenerative changes developing with age in the ultrastructure of carotid bodies. On the other side, respiratory responses to hypoxia in old women were well preserved and were no less than those in young women. Therefore, a discrepancy appeared between the morphological and functional aspects. These findings suggest development of compensatory mechanisms in brain respiratory areas which maintain primary defensive reflexes, such as the hyperventilation of hypoxia.
16
Content available remote Sense of social interaction in the elderly
51%
Pokorski M. , Cajdler A. , Menzyk K.
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2008
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tom 59
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nr 6
573-578
17
Content available remote Ultrastructural degradation of the carotid body in the aged rat: is there a role for atherosclerosis in the main carotid arteries?
51%
Dymecka A. , Walski M. , Pokorski M.
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nr 4
85-90
EN
In this study we examined the potential role of atherosclerosis in the main arteries supplying blood to the carotid body in the organ’s morphological degradation with age. We addressed this issue by comparing the ultrastructural picture of carotid bodies and of fragments of the carotid artery bifurcation in two age-extreme groups of rats: young - 3 months old and senescent - 24 months old. Tissues were excised under surgical anesthesia, fixed in aldehydes, and processed for transmission electron microscopy. We found that the old carotid body parenchyma exhibited profound degenerative changes. Chemoreceptor cells were at various stages of atrophy, ranging from swollen mitochondria and fewer secretory vesicles to dark dehydrated cells. In contrast, the senescent carotid artery bifurcation was little different from that in young rats. Particularly, endothelial cells were in perfect condition. There were some changes in deeper arterial wall layers such as breaks in the continuity of elastic bands or a subtly different phenotype of smooth muscle cells. No foam cells or calcium build-ups were found in the arterial walls. Such changes correspond to the process of arterial wall stiffening in old age rather than to the outright atherosclerosis. Lack of atherosclerosis in the common carotid arteries, which could hamper blood flow, argues against its playing a role in the morphological age-changes in the carotid bodies.
18
Content available remote Membrane association of N-oleoyl-dopamine in rat brain
51%
Zajac D. , Matysiak Z. , Czarnocki Z. , Pokorski M.
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nr 4
403-408
EN
N-oleoyl-dopamine (OLDA) belongs to a novel class of bioactive amides of fatty acids. The compound, a lipid derivative of dopamine, holds promise as a potential prodrug or carrier of dopamine into the brain. In this context, a key issue concerning OLDA is the integrity of the compound once it enters the brain. We addressed this issue in the current study by assessing the propensity of OLDA for hydrolysis in rat brain tissue in vitro. The brains were dissected from surgically anesthetized rats after they had been sacrificed by perfusion with physiological saline through the heart. Membrane fractions of brain tissue were isolated and incubated with 1 mmol/l OLDA. Stability of the OLDA molecule was assessed from the spectrophotometric recordings of OLDA spectra in membrane fractions at hourly time points for up to 24 hours. The methodological assumption was that any major change in the shape of the OLDA spectrum would point to a structural, and thus also possibly functional, alteration of the molecule. We found that the OLDA spectrum remained unchanged in the assays for up to 17 h of incubation. We conclude that OLDA strongly resists hydrolysis in brain membrane fractions. The results suggest that dopamine-like biological effects of OLDA might have to do with the interaction of the integral OLDA compound, rather than a dissociated-off dopamine moiety, with the dopaminergic system.
19
Content available remote A common oxygen sensor regulates the sensory discharge and glomus cell HIF-1alpha in the rat carotid body
51%
Lahiri S. , Antosiewicz J. , Pokorski M.
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tom 58
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nr 5
20
Content available remote Poly(ADP-ribose) polymerase activity in the cat carotid body in hypoxia and hyperoxia
51%
Strosznajder R. P. , Jesko H. , Pokorski M.
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nr 3
EN
Reactive oxygen species (ROS) induce DNA damage with the ensuing activation of the chromosomal repair enzyme poly(ADP-ribose) polymerase (PARP). ROS also interact with the function of carotid body chemoreceptor cells. The possibility arises that PARP is part of the carotid chemosensing process. This study seeks to determine the presence of PARP and its changes in response to contrasting chemical stimuli, hypoxia and hyperoxia, both capable of generating ROS, in cat carotid bodies. The organs were dissected from anesthetized cats exposed in vivo to acute normoxic (PaO290 mmHg), hypoxic (PaO225 mmHg), and hyperoxic (PaO2> 400 mmHg) conditions. Carotid body homogenate was the source of PARP and [adenine 14C] NAD was the substrate in the assay. Specimens of the superior cervical ganglion and brainstem were used as reference tissues. We found that PARP activity amounted to 27 pmol/mg protein/min in the normoxic carotid body. The activity level more than doubled in both hypoxic and hyperoxic carotid bodies. Changes of PARP in the reference tissues were qualitatively similar. We conclude that PARP is present in the carotid body but the augmentation of the enzyme activity in both hypoxia and hyperoxia reflects DNA damage, induced likely by ROS and being universal for neural tissues, rather than a specific involvement of PARP in the chemosensing process.
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