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Biomedical subjects

P Cour

Publications and source records attributed to P Cour.

8 recordsLinked to original sources
PubMed1991

Clinical and immunologic reactivity of patients allergic to grass pollens and to multiple pollen species. I. Clinical and immunologic characteristics.

The heterogeneity of pollen-allergic individuals is well-known but poorly characterized. Twenty-six patients were studied to characterize their immunologic and clinical patterns. Thirteen patients were allergic only to grass pollens, and 13 other patients were allergic to grass-pollen and other pollen species, including Cupressaceae, plane tree, olive, and Parietaria. The IgE response was assessed by the titration of serum total IgE and orchard grass-specific IgE, as well as by IgE immunoblots to orchard-grass pollens. Clinical reactivity was assessed by nasal challenge with orchard-grass pollens before the pollen season and nasal and bronchial symptom-medication scores between April 1 and June 15. Pollen counts were obtained during this period of survey. Polysensitized patients had significantly increased levels of serum total and specific IgE and a greater heterogeneity of IgE immunoblots, suggesting an enhanced qualitative and quantitative IgE immune response. Polysensitized patients had nasal and bronchial symptoms occurring earlier than grass pollen-allergic individuals, confirming the priming effect caused by other plans flowering with an earlier season for both nasal and bronchial mucosa. Alternatively, the early symptoms may be attributable to the tree pollens or might reflect the higher grass-pollen IgE level in the polysensitized group. Bronchial symptoms appeared a few weeks after nasal symptoms. Nasal challenges were similar in both groups, and the severity of nasal symptoms during the season was not significantly different in both groups, suggesting that the intensity of symptoms is not related to the sensitization nor to the IgE immune response of the subjects.

Adolescent↗
PubMed1987

[Correlation between the atmospheric level of antigen Amb-al (AgE) and the number of Ambrosia artemisiaefolia pollen grains in Lyon and neighboring regions].

Accurate quantitation of the atmospheric levels of pollens and other allergenic particulate is laborious and may not always correlate with the concentration of allergen within the particulate. This study examined the atmospheric contamination by short ragweed (Ambrosia artemisiae folia) over 7 weekly periods during ragweed pollination in 6 localities of France centered around Lyon. The correlation between data obtained from the conventional microscopic numeration of pollen grain and and the quantitation of the allergen Amb-al level by radioimmunoassay was investigated. For the total of 41 paired analyses of the actual numbers of ragweed pollen grains and computed numbers of pollen grains from the Amb-al levels there was an excellent overall correlation (r = 0.90, p 0.001) thus the radioimmunoassay of Amb-al represent a simple and relevant alternative to microscopic numeration of pollen grains.

Air Pollutants↗
PubMed1978

Enzyme determination and RAST inhibition assays for orchard grass (Dactylis glomerata): a comparison of commericial pollen extracts.

Pollens release enzymes when they are dropped into water. Orchard Grass extracts were tested by two methods. The Api-Zym System determined 19 enzymes and colorimetric amounts of Leucine Aminopeptidases, Acid phosphatase and trypsin. These were compared with RAST inhibition assays. A good correlation was shown between the techniques. Thus the enzyme dosage may be useful for the standardization of pollen extracts.

Dose-Response Relationship, Immunologic↗
PubMed1977

Penetration of inhaled pollen into the respiratory tract.

The pathophysiologic mechanisms of pollen-induced asthma have heretofore remained unclear, because pollen particles have generally been considered too large to penetrate into the lower respiratory tract. Such grains are therefore believed to be unable to induce an immunologic response in the lower respiratory tract. Nevertheless, experimental curves of particle penetration into the respiratory tract indicate that a small percentage of large-sized particles may penetrate into the peripheral areas of the lungs. Under the conditions of our study, a radioisotopic method using labeled pollen grains was not effective in detecting the very small number of grains expected to be found in the lung. We used another simpler and more effective method derived from techniques used by palynologists in the detection of pollen grains in sediments. According to our results, which showed pollen grains normally present in tracheobronchial secretions and in lung parenchyma, we can safely assume that inhaled pollen does penetrate into the distal lower respiratory tract. At present, we do not know the precise number of pollen grains necessary to trigger a response, and we do not know the behavior of these grains with regard to the mucous membranes of the small bronchi and the alveoli. It is important to determine whether these grains have an effect on these areas and whether a direct mechanism is involved in the genesis of pollen-induced asthma.

Aged↗
PubMed1976

Qualitative and quantitative comparison of pollen calendars for plain and mountain areas.

A comparison of the quantity and the quality of pollen content in the atmosphere of two regions, one of the plains bordering the Mediterranean sea (altitude 40 m), the other of the mountains of the Pyrenees (altitude 1550 m), was made during the climatological year 1974-1975. The method which was used intercepts the pollen flux of the atmosphere with a vertical filtering unit, which is exposed facing the direction of wind on the filtering door of the weather-vane and collects much larger quantities of pollen than the other techniques of collection. The atmospheric currents displace from one region to another numerous spores and pollens, the trajectories of which are directly influenced by the general circulation of the atmosphere. The density of these fluxes can be very large, reaching 2500 grains/m3 of air at M.T.P.R. in the last week of January; the taxons collected are very numerous (more than 700). The atmospheric transfer of pollen modifies largely the pollen content of the atmosphere of different flowering domains. These interferences manifest themselves in the simplest cases by the presence of two peaks of concentration, the principal corresponding to the local efflorescence, the second to the pollen transferred from other regions. The pollen concentrations in the mountains are one-third of those in the plains. Pollination in the mountains is several weeks late in comparison to the plain during the first semester, whereas during the second semester, it is the plains that show a certain delay. These findings show why some allergic patients who go to the mountains during summer are affected twice by pollination.

Air Pollution↗
PubMedDate not supplied

Analysis of commercial pollen extracts by enzyme determination. II. Determination of the contamination of pollen extracts with plant matter.

The contamination of pollen extracts by plant matter was studied by means of enzymes. Beta-glucosidase was detected only in flowers and leaves by using the Api-Zym System. 29 pollen extracts were prepared after microscopic control. Among these 23 did not contain any plant matter and no beta-glucosidase activity could be detected. In contrast, 6 extracts were contaminated with plant matter and in every case beta-glucosidase activity was found 34 commercial pollen extracts completed the study. beta-glucosidase activity was present in 8 of them. It may be postulated that glucosidase activity detected using 2- naphthyl - beta D-glucopyranoside as a substrate, can be correlated with the presence of plant matter from the raw material from which the extract was prepared. This contamination may be important to determine since some additional sensitization may occur with such extracts during immunotherapy.

Drug Contamination↗