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A Oddoy

Publications and source records attributed to A Oddoy.

At least 19 recordsLinked to original sources
PubMed2005

Elemental carbon and respirable particulate matter in the indoor air of apartments and nursery schools and ambient air in Berlin (Germany).

UNLABELLED: This study was performed to examine exposure to typical carcinogenic traffic air pollutants in the city center of an urban area. In all, 123 apartments and 74 nursery schools were analyzed with and without tobacco smoke interference and the households in two measuring periods. Simultaneously, the air outside 61 apartment windows as well as the average daily traffic volume were measured. Elemental carbon (EC), the marker for particulate diesel exhaust and respirable particulate matter (RPM) were determined. The thermographic EC analysis was conducted with and without prior solvent extraction of the soluble carbon fraction. Comparison of these two thermographic EC measurements clearly showed that method-related differences in the results, especially for indoor measurements, when high background loads of organic material were present (e.g. tobacco smoke), existed. Solvent extraction prior to EC determination was therefore appropriate. For the first winter measuring period, the EC concentration levels without solvent extraction in the indoor air were about 50% higher than those measured in the spring/summer period. In the second measuring period (i.e. spring/summer), the median EC concentrations after solvent extraction were 1.9 microg/m3 for smokers' apartments and 2.1 microg/m3 for non-smokers' apartments, with RPM concentrations of 57 and 27 microg/m3, respectively. Nursery schools showed high concentrations with median values of 53 microg/m3 for RPM and 2.9 microg/m3 for EC after solvent extraction. A significant correlation between the fine dust and EC concentrations (after solvent extraction) in the indoor and ambient air was determined. Outdoor EC values were also correlated with the average daily traffic volume. The EC ratios between indoor and ambient concentration showed a median of 0.8 (range: 0.3-4.2) in non-smoker households and 0.9 (range: 0.4-1.5) in smoker apartments. Furthermore, the EC/RPM ratio in indoor and ambient air was 0.01-0.15 (median 0.06) and 0.04-0.37 (median 0.09), respectively. PRACTICAL IMPLICATIONS: In the absence of indoor sources a significant correlation with regard to respirable particulate matter (RPM) and elemental carbon concentrations between the indoor and ambient air of apartments was observed. The high degree of certainty resulting from this correlation underscores the importance of ambient air concentrations for indoor air quality. In nursery schools we found higher concentrations of RPM. An explanation of these results could be the high number of occupants in the room, their activity and the cleaning intensity.

Adult↗
PubMed2004

Polycyclic aromatic hydrocarbons inside and outside of apartments in an urban area.

In the context of environmental monitoring in Berlin polycyclic aromatic hydrocarbon (PAH) concentrations in air and household dust were measured inside 123 residences (and simultaneously in a sub group in the air outside the windows). The aim of this study was to determine exposure to PAHs in the environment influencing by several factors, for instance, motor vehicle traffic in a populous urban area. Indoor air samplings were carried out in two periods (winter and spring/summer) in smokers and non-smokers apartments. Benzo(a)pyrene (BaP) median values were 0.65 ng m(-3) (winter) and 0.27 ng m(-3) (spring/summer) in smokers' apartments and 0.25 ng m(-3) (winter) and 0.09 ng m(-3) (spring/summer) in the apartments of non-smokers. The median BaP content in ambient air was 0.10 ng m(-3) (maximum: 1.1 ng/m(-3)) with an indoor-outdoor mean concentration ratio of 0.9 in non-smoker households and 5.4 in smoker apartments. In household dust we obtained median values of 0.3 mg kg(-1) (range: 0.1-1.4 mg kg(-1)). We found a significant relation between indoor and outdoor values. Approximately 75% of the variance of indoor air values was caused by the corresponding BaP concentrations in the air outside the apartment windows. Otherwise a significant correlation between indoor air and household dust values cannot be found. Therefore, according to our results, it is suggested that the indoor PAH concentration in non-smoker apartments could be attributed mainly to vehicular emissions.

Air Pollutants↗
PubMed2004

Occurrence of phthalates and musk fragrances in indoor air and dust from apartments and kindergartens in Berlin (Germany).

UNLABELLED: In this study, the occurrence of persistent environmental contaminants room air samples from 59 apartments and 74 kindergartens in Berlin were tested in 2000 and 2001 for the presence of phthalates and musk fragrances (polycyclic musks in particular). These substances were also measured in household dust from 30 apartments. The aim of the study was to measure exposure levels in typical central borough apartments, kindergartens and estimate their effects on health. Of phthalates, dibutyl phthalate had the highest concentrations in room air, with median values of 1083 ng/m(3) in apartments and 1188 ng/m(3) in kindergartens. With around 80% of all values, the main phthalate in house dust was diethylhexyl phthalate, with median values of 703 mg/kg (range: 231-1763 mg/kg). No statistically significant correlation could be found between air and dust concentration. Musk compounds were detected in the indoor air of kindergartens with median values of 101 ng/m(3) [1,3,4,6,7,8-hexahydro-4,6,6,7,8,8- hexamethylcyclopenta-(g) 2-benzopyrane (HHCB)] and 44 ng/m(3) [7-acetyl-1,1,3,4,4,6-hexamethyl-tetraline (AHTN)] and maximum concentrations of up to 299 and 107 ng/m(3) respectively. In household dust HHCB and AHTN were detected in 63 and 83% of the samples with median values of 0.7 and 0.9 mg/kg (Maximum: 11.4 and 3.1 mg/kg) each. On comparing the above phthalate concentrations with presently acceptable tolerable daily intake values (TDI), we are talking about only a small average intake [di(2-ethylhexyl) phthalate and diethyl phthalate less than 1 and 8% of the TDI] by indoor air for children. The dominant intake path was the ingestion of foodstuffs. For certain subsets of the population, notably premature infants (through migration from soft polyvinyl chloride products), children and other patients undergoing medical treatment like dialysis, exchange transfusion, an important additional intake of phthalates must taken into account. PRACTICAL IMPLICATIONS: The phthalate and musk compounds load in a sample of apartments and kindergartens were low with a typical distribution pattern in air and household dust, but without a significant correlation between air and dust concentration. The largest source of general population exposure to phthalates is dietary. For certain subsets of the general population non-dietary ingestion (medical and occupational) is important.

Air Pollution, Indoor↗
PubMed1998

Polycyclic aromatic hydrocarbons (PAH) and diesel engine emission (elemental carbon) inside a car and a subway train.

Significant concentrations of potentially harmful substances can be present in the interior of vehicles. The main sources of PAHs and elemental carbon (EC) inside a car are likely to be combustion emissions, especially from coal and traffic. The same sources can also be important for the interior of a subway train for which there are specific sources in the tunnel system, for example diesel engines. Twice, in summer 1995 and winter 1996 polycyclic aromatic hydrocarbons (PAH) and diesel motor emission (estimated as elemental carbon) were determined in the interior of a car (a 2-year-old VW Golf with a three-way catalytic converter) and in the passenger compartment of a subway train (below ground). On each sampling day (in total 16 daily measurements in the car and 16 in the subway) the substances were determined in the breathing zone of the passengers from 07:00 h to 16:00 h under different meteorologic conditions (winter- and summertime). The car followed the route of the subway from the western Berlin borough of Spandau to the south-eastern borough of Neukölln, and back. The sampling represented a realistic exposure model for driving in a high traffic and polluted urban area. The electric subway train (also 2 years in use) connected the same parts of Berlin (31 km underground). The mean values obtained during the two measurement periods (summer/winter) inside the car were 1.0 and 3.2 ng/m3 for benzo[a]pyrene, 10.2 and 28.7 ng/m3 for total-measured-PAHs, 14.1 and 8.2 micrograms/m3 for EC and in the subway 0.7 and 4.0 ng/m3 for benzol[a]pyrene, 30.2 and 67.5 ng/m3 for total PAHs, 109 and 6.9 micrograms/m3 for EC. A comparison between subway and car exposures shows significantly higher concentrations of PAHs in the subway train, which can be explained by relatively high concentrations of fluoranthene and pyrene in the subway. So far a satisfactory explanation has not been found, but one source might be the wooden railway ties which were formerly preserved with tar based products. In wintertime in both transportation systems the concentrations of beno[a]pyrene are three to four times higher than in summer corresponding to the changing of the ambient air concentrations.

Berlin↗
PubMed1998

[Exposure of the population to volatile organic compounds inside an automobile and a subway train].

Air quality, in particular in urban regions, is affected by the emissions of the traffic and meanwhile for some substances motor vehicles became the dominating source. For valid quantitative risk assessment of the general population it is necessary to have informations about the main routes of exposure. Therefore in a pilot study 1994 and two times in summer 1995 and winter 1996 aromatic hydrocarbons, carbon monoxide (CO) and carbon dioxide (CO2) were determined under different meteorologic conditions inside of a car (a two year old VW-Golf with a three-way catalyst) and in a subway-train. The car route followed the subway (31 km underground) and crossed the central parts of Berlin in streets with high traffic density. The mean values for benzene obtained during the three measurement periods inside the car were 21.1/21.5 and 21.6 micrograms/m3 (daily maximum: 31.9/26.3 and 35.0 micrograms/m3) and inside the subway 8.4/5.4 and 7.4 micrograms/m3 (daily maximum: 16.0/7.4 and 10.3 micrograms/m3). The mean levels of CO in the car were 6 ppm (summer) and 5 ppm (winter) respectively, with peak concentrations of 33 and 70 ppm (10-minutes maximum). In the subway the values were 2 ppm (summer and winter); (10-minutes maximum: 5 and 12 ppm). A comparison between the two types of traffic shows three times higher concentrations of benzene inside the car. Our results demonstrate that the exposure of car occupants to benzene has to be taken into account for risk assessment. The concentration of CO inside the car is three to four times higher than in the subway train. Compared with other studies we found only low concentrations of CO inside the car.

Air Pollution, Indoor↗
PubMed1991

[Effects of the PAF antagonist WEB 2086 on hypoxia and angiotensin II-induced pulmonary vasoconstriction in the isolated perfused rat lung].

Using isolated blood-perfused lung preparations of rats, we tested the influence of the PAF antagonist WEB 2086 on vasoconstriction triggered by hypoxia or angiotensin II (A II). If a constant flow was pre-set, changes in the prepulmonarily measured pressure were directly related to the changes of resistance in the pulmonary flow. WEB 2086 reduced the hypoxically conditioned vasoconstriction (HPV) when using blood as perfusion medium, the effect being dependent on the dose (ED50 = 127.3 +/- 21.1 mg/l). HPV was lowered on the average by 82% if the full pharmacologic dose of 800 mg/l WEB 2086 was added to the perfusate. The A II response was weakened to a lesser degree (by 45%). If plasma was used as perfusate, the pressure increase in response to hypoxic stimulation or A II was less marked. However, the relative effect of the PAF antagonist was analogous (attenuation by 83% or 53%, respectively). In chronically hypoxic animals (3 weeks at 10% O2) the relative pressure drop in the lesser circulation after application of WEB 2086 (400 mg/l; HPV; blood as perfusate) was definitely more pronounced (p less than 0.001). The fact that WEB partly antagonises the pulmonary vasoconstriction triggered both by alveolar hypoxy and by angiotensin II, seems to indicate that in both constrictive stimuli PAF participates in the complex mediator mechanism or that WEB 2086 exercises a non-specific vasodilatory effect on the pulmonary flow.

Angiotensin II↗
PubMed1991

Effects of ligustrazine on the pressure/flow relationship in isolated perfused rat lungs.

Ligustrazine, the synthesized principle of a Chinese herbal remedy shown previously to be a pulmonary vasodilator, was tested in chronically hypoxic and normal rats. Pressure/flow, (P/Q), relations were measured in isolated perfused lungs during normoxia, hypoxia and after reversal of hypoxic vasoconstriction by increasing doses of ligustrazine. P/Q lines were linear over a wide range and extrapolation to the pressure axis gave an intercept which was the effective downstream pressure for flow. In chronically hypoxic rats the slope of the line was steeper and the intercept greater than in control rats, which we attributed to newly muscularized arterioles with tone. Hypoxia caused an increase in slope and intercept in both groups but the intercept increase was greater in chronically hypoxic rats. In both groups of rats increasing doses of ligustrazine given during continued hypoxia caused a fan of lines which moved progressively towards the control normoxic line. In chronically hypoxic rats it required only 2 mg of ligustrazine to bring the line back to the normoxic position, whereas in controls it required 4 mg. In chronically hypoxic rats the change in intercept with every dose was greater than in control rats; this suggests that ligustrazine mainly relaxes the muscle of small collapsible vessels. The action of ligustrazine remained in both control and chronically hypoxic rats after administration of an arginine analogue which blocks synthesis of the endothelial relaxant factor nitric oxide. This and previous evidence suggest that ligustrazine is a non-endothelial-dependent pulmonary vasodilator.

Animals↗
PubMed1991

[A standardized in vivo model for determining the effectiveness of surfactant preparations].

The premature rabbit neonate of the 27th day of gestation is a useful model for testing intratracheally applied surfactant preparations. Immediately after application of an effective surfactant the thorax lung compliance--as the decisive measure--rises significantly. We could exclude effects of the applied fluid per se. The most reliable result about the efficiency of a surfactant preparation is given by the cumulative dose response relationship. In a semilogarithmic system there is a linear relationship between the surfactant dose (25-200 mg phospholipids per kg b.w.) and the thorax-lung-compliance.

Animals↗
PubMed1991

The influence of intratracheal saline upon the dynamic lung-thorax compliance of premature newborn rabbits.

A modern therapy for the respiratory distress syndrome in neonates is the substitution of alveolar surfactant. Supplementary surfactant has to be applied to the lung via an aqueous emulsion. To estimate the effects of fluids instilled into the lungs a total of 144 premature newborn rabbits were used. They were delivered by hysterotomy after 27, 28 or 29 gestational days (term = 31 +/- 1 days; mean +/- SD), anaesthetized (0.5 mg ethylurethane/kg b.w.), paralyzed (1 mg pancuronium bromide/kg b.w.) and ventilated by positive pressure (P = 25 hPa; f = 40/min; I:E = 1:1) with 100% oxygen. By means of body-plethysmography the tidal volume (VT) was recorded before and regularly during 90 min after the application of 0 (controls), 5, 10 or 20 ml saline (0.9% NaCl solution) per kg b.w. intratracheally. Dynamic lung-thorax compliance (Crs) was calculated as VT/P and related to the body weight. The initial Crs values (mean +/- SD) were 0.06 +/- 0.02 (27 days), 0.62 +/- 0.52 (28 days) and 1.08 +/- 0.21 (29 days) ml/hPa/kg, respectively (p less than 0.001). Intratracheal saline application had no detectable effect on Crs in rabbit neonates on day 27 of gestation. On day 28 or 29 of gestation there was a transient (approximately 15 min) Crs reduction, increasing with the volume of applied liquid. At a given saline quantity the severity of Crs reduction depended more on the magnitude of the initial Crs values than on the gestational day.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

[Hypoxic pulmonary vasoconstriction following lung damage by xanthine oxidase--studies in rats].

The main reason for an insufficient oxygenation of the arterial blood during acute lung injury should be an increased shunt fraction. The aim of this study was to check if in this connection the magnitude of hypoxic pulmonary vasoconstriction is reduced--a fact, which could be causal involved in the arising of increased shunt fraction. 21 male rats were anaesthetized (pentobarbitone) and ventilated artificially (F1O2 = 0.6). In 10-minute-intervals hypoxia (F1O2 = 0.06) was applied. After the first hypoxic exposure the animals were divided into 4 groups according to the application of 3 U xanthine oxidase (XO) or 0.5 ml physiological saline (NaCl) intratracheally (i.t.) or intravascularly (i.v.)--group A: XO i.t.; group B: XO i.v.; group C.: NaCl i.t.; group D: NaCl i.v. At the end of each hypoxic or hyperoxic period (steady state) mean blood pressure in the right ventricle (Prv) and in the A. carotis communis (Psa) were measured. Then blood samples (100 microliters each) were drawn from the artery and the right ventricle and pH, PO2, PCO2, SO2 and hemoglobin concentration were determined. During hyperoxic conditions from the latter values we calculated the shunt fraction. Additional the lung-thorax compliance before and after the application was measured body plethysmographically. As an indirect measure of the reagibility of the pulmonary vasculature the increase of Prv during hypoxic exposure was considered. In the groups B, C and D no significant changes between the measured parameters before and after the application procedure could be observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

Increase of the oxygenation and decrease of the intrapulmonary peak pressure at constant mean airway pressure using high-frequency jet ventilation in adult rabbits with lavage-induced severe respiratory distress syndrome compared to conventional mechanical ventilation.

Reports are contradictory about the value of high-frequency jet ventilation (HFJV) in the treatment of respiratory distress syndrome (RDS) [10, 11, 18 - 1, 2, 22, 25]. In a preliminary study on rabbits with healthy as well as surfactant deficient lungs, caused by lung lavage, at a constant mean airway pressure (MAP) and 20% inspiration time, the influence of the jet ventilation frequencies of 1, 3, 5, 10, 15 and 20 Hz (cycles per second) on the pressure oscillations along the airways as well as on blood gas and cardiac parameters were investigated. It was presumed that the breathing level, e.g. functional residual capacity plus 50% of the tidal volume is the same at constant MAP. The results during HFJV are compared to those of conventional mechanical ventilation (CMV). With increasing frequency the peak airway pressure (PAP) clearly decreased on both groups, while the self controlled positive end-expiratory pressure (AUTO-PEEP) increased. That means, the amplitude of the pressure oscillations became smaller and smaller, indicating that the danger of mechanical lesions might be reduced by this mode of ventilation. The arterial oxygenation (PaO2) increased with frequency. A threefold higher PaO2 could be obtained at 10 Hz in the animals with RDS lungs. The arterial carbon dioxide tension (PaCO2) increased nearly linear with the frequency in both groups. The inverse course of the arterial pH showed that it is possible to obtain at lower frequencies a respiratory alkalosis and at higher frequencies an acidosis. Optimal gas exchange could be obtained at about 10 Hz. Decreasing cardiac output with increasing frequency showed a good correlation to the pH in both groups. The effect was more influenced by the heart frequency than by the stroke volume especially in the RDS-group.

Animals↗
PubMed1989

[Equipment combination for the use of normal frequency and high frequency jet ventilation].

Over the last eight years high-frequency ventilation has been extensively evaluated both in the clinical and laboratory settings. Two types of jet ventilators for application of normofrequency and high-frequency jet ventilation have been developed. A combined equipment is described with gas mixer, heater-humidifier, monitoring, membrane solenoid valve and a special injection system.

High-Frequency Jet Ventilation↗
PubMed1989

[Experiences with the use of oscillating high frequency ventilation].

Our investigations have demonstrated that the effect of oscillatory high-frequency ventilation (HFO) on gas exchange in dogs is directly proportional to the oscillatory flow amplitude VM. Because of the equation: VM = PM/Z, gas exchange is increasing with rising oscillatory amplitude of the ventilation pressure PM and decreasing with rising impedance Z of the respiratory system. This system consists of endotracheal tube and the lungs of the dog investigated. The impedance Z = square root of R2 + X2 (resistance R and reactance X) achieves a minimal value near at the resonant frequency (reactance X = 0, in healthy intubated dogs near at 5 Hz) and increases with rising oscillatory frequency. Thus the oscillatory high-frequency ventilation is most effective near to the resonant frequency of the respiratory system. The results presented allow the conclusion that the application of high-frequency ventilation can be optimized by monitoring the respiratory mechanics parameters.

Animals↗
PubMed1988

Respiratory failure caused by intratracheal saline: additive effect of xanthine oxidase.

Administration of physiological saline or drugs together with saline into the airways is becoming common clinical practice. However, there are few studies on possible side effects. We have studied the effects of saline, saline plus xanthine oxidase, and saline plus xanthine oxidase plus superoxidase dismutase on lung-thorax compliance and on arterial blood gases in anesthetized, paralyzed guinea pigs, ventilated for 2.5 h. Saline bolus (2-3 ml isotonic saline/kg body weight) into the airways reduced the compliance within 20 min to a mean of 39% of the pretreatment levels, and necessitated as increase in the respirator pressure. Saline plus xanthine oxidase decreased the compliance to 16% of the pretreatment levels. The xanthine oxidase-induced (but not saline-induced) decrease in lung compliance was relieved by superoxide dismutase. According to the present results xanthine oxidase induces a lung injury possible by production of free oxygen radicals. Superoxide dismutase can be valuable in prevention of free oxygen radical-mediated lung damage. Saline alone can be harmful when applied to the airways. This should be considered in clinical trials and in clinical practice.

Animals↗
PubMed1988

[Animal experiment studies of morphologic changes in the trachea and lung in high frequency ventilation].

Prolonged high frequency ventilation (24 hrs) in dogs leads to morphological changes in the trachea as well as in the bronchi. Erosive changes of tracheal epithelium were observed whereas small bronchi and bronchioli exhibited luminal obstructions by mucus plugs, caused by hypersecretion of goblet cells. Using histochemical methods degenerative changes of bronchiolar epithelium were observed.

Animals↗
PubMed1987

Acute and chronic effects of xanthine oxidase on lung thorax-compliance in guinea pigs.

Xanthine oxidase was given intratracheally in a single dose to guinea pigs. Lung compliance was measured after 4 h and 14 days respectively. Lung-thorax compliance was significantly lower compared with saline-treated controls both 4 h and 14 days after application of fluid. At 14 days there was a dose-related response between lung-thorax compliance and xanthine oxidase administered in the range 0-1.0 U. Superoxide dismutase (SOD) had a protective effect on xanthine oxidase action at 4 h, but not after 14 days. We suggest that the decreased lung-thorax compliance was caused by superoxide radicals, produced by the hypoxanthine-xanthine oxidase system, damaging lung tissue. We speculate that free oxygen radicals produced by the hypoxanthine-xanthine oxidase system could be an important contributory pathogenetic factor in producing both acute and chronic lung damage in, for instance, premature babies or adults, with respiratory distress syndrome.

Animals↗