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Currently, the role of dopaminergic and somatostatinergic agonists in the treatment of pituitary adenomas is quite well established. Nevertheless, a clearer understanding of the expression of dopaminergic and somatostatinergic receptors at the cellular level of pituitary adenomas as well as the development of newer analogues compounds may drastically change current therapeutic modalities. In particular, the emphasis on the co-expression of different receptors types or subtypes in adenomatous cells highlights functional interactions between receptors leading to an increase in their activity. Newer molecules are also in the process of development : new somatostatin analogues with more universal binding properties to different receptors subtypes, as well as chimeric molecules capable of binding to somatostatinergic and dopaminergic receptors. In the midst of GH-secreting pituitary adenomas, a positive correlation exists between the expression of Sst2 mRNA and the inhibition of GH release by somatostatin analogues. The involvement of Sst5 subtype in adenomas resistant to preferential Sst2 agonists has recently been proved. Another recently developed compound has a more universal Sst binding profile. This compound, named SOM-230, has a 25, 5 and 40 times higher binding affinity to Sst1, Sst3 and Sst5 receptors respectively, and 2,5 times lower affinity to Sst2, when compared to octreotide. SOM-230 could therefore allow for much more effective methods in treating patients suffering from acromegaly. Besides, the use of a chimeric molecule presenting a binding affinity to both Sst2 and D2 subtypes (BIM-23A287) inhibits the secretion of GH in ways similar to the Sst2 or D2 agonists used alone or concurrently but however in a concentration 50 times lower than that of the latter. The discovery of Sst5 and D2 subtypes at the level of corticotropic adenomas reveals newer therapeutic perspectives with promising preliminary results with the use of SOM-230 ; these finding lead to a rise in interest in cabergoline. In the midst of non-functioning pituitary adenomas, the expression of Sst2, Sst3 and D2 receptors will perhaps allow the use of combined therapies associating the new somatostatin analogues to the dopaminergic agonists or even use dopastatin (BIM-23A760, chimeric molecule Sst2-Sst5-D2). The preliminary results obtained in vitro with this molecule are actually encouraging since they show a dose dependent inhibition of the cellular replication mechanisms in 60 % of the cases. Finally, concerning prolactinomas the discovery of Sst5 receptors lead to consider the use of somatostatinergic agonists specific to the Sst5 receptor, SOM-230 in particular. Nevertheless, it seems that adenomas resistant to dopaminergic agonist due to a lack of expression of D2 receptor fail to express Sst5 receptors as well. On the other hand, dopastatin appears to be more efficient than cabergoline in the management of this type of adenomas. Therefore, the growing awareness concerning the mechanisms involved in the control of pituitary secretions as well as cellular proliferation will perhaps allow physicians to treat the pathology of pituitary adenomas, macroadenomas in particular, using solely pharmacological means instead of invasive surgical procedures and/or radiotherapy.

Three strains of mice were given, per os and ad libitum, a spa water containing 6.8 mg/l arsenic and indicated for the treatment of allergic respiratory diseases or chronic bronchitis. The daily arsenic intake was approximately from 1.5 to 4 mg/kg. No effect on body weight gain or on the various immune parameters assessed was observed. These results demonstrate that this spa water, despite its high arsenic content, is not toxic and does not interfere with the immune system of healthy mice.

Transfer factor (TLCO) and its components (TMCO and Vc) have been measured in 47 healthy subjects. The regressions with respect to age and body surface were close to those found in the literature. The reproducibility of these indices has been investigated in a sub-group of 5 subjects, examined at two days intervals, for 24 to 42 days. For TLCO measured with a 16% O2 mixture, the reproducibility was good (coefficient of variation of 5%). For Vc and TMCO, the dispersion was more important and varied among the subjects. The lack of reproducibility appeared to be due, among other factors, to reading errors on the variables, and more frequently FACO. Four among these 5 subjects were asked to keep alveolar pressure close to atmospheric during the apnea; the coefficient of variation decreased from 23.5 to 7.5% for Vc and from 25.9 to 12.4% for TMCO.

An experimental approach of the intrapulmonary deposition of particles with a diameter below 1 micron, suspended in the surrounding atmosphere, was done on two normal subjects during inspiratory apnea with a Whitby impactor. The first results seem to agree with those of literature and confirm the importance of pulmonary morphometric factors in the deposition processes. Numerous methodological problems remain, but it appears that the technique would be useful to evaluate the likelyhood of deposition of submicron particles which are presently known to be pathogenic.

The aerosol of thermal water given just before the administration of spasmogenic substances did not prevent the histamine or acetylcholine induced bronchospasm. After a daily parenteral dose of thermal water during 21 days, a systemic delay of the bronchospasm induced by both mediators was observed. With arsenic pretreatment the delay in onset of bronchospasm was shorter.

The authors made a study of the antihistaminic properties of Pipoxizine in 20 subjects with proven histaminic hyperreactivity. The design of the trial consisted in comparing the changes of VC, FEC1, expiratory airway resistance and V50 produced by a histamine aerosol given before and after administration of Pipoxizine. Pipoxizine was given by mouth to 10 patients and intravenously to the other 10 of the group. The statistical analysis of the results demonstrated an antagonist effect of Pipoxizine on the histamine induced bronchoconstriction. The data of this trial are confirmative of the results of other experimenters. It seems therefore reasonable to take into consideration the use of Pipoxizine in the preventive treatment of the paroxystic attacks of the asthmatic disease.

The result of a study done on 52 subjects including a thorough ventilatory functional test and the radioisotopic measurement of inhaled particles deposition, by working out the TB/P ratio, revealed that: 1. giving aerosol needs an exacting technique when used for quantitative aims; 2. ratio TB/P is increased in patients with chronic broncho-pulmonary diseases, because of a predominantly tracheo-bronchial deposition of particles; 3. in patients with a satisfactory ventilatory function the TB/P ratio is increased; on the other hand in patients with ventilatory disorders, the ratio is normal. The repartition of particles deposition between the compartments TB and B depends therefore not only on factors involving ventilatory functional values but also on the physiopathological factors not included in them.

Spirometric data, resting Pao2 and Paco2 have been statistically evaluated in 152 patients with chronic obstructive bronchitis. Spirographic studies show a restrictive and obstructive syndrome, associated with hypoxaemia and hypercapnia. Partial correlations show that Pao2 is positively correlated with age and negatively with VC (predicted percentage) and with FEV1 (predicted percentage); Paco2 is only correlated with FEV1 (predicted percentage). FEV1 (predicted percentage) divides the patients into two groups, the hypercapnic and normocapnic. These data show the interest of the FEV1 (predicted percentage) values.

PaO2 and PaCO2, after 5 min of a 40-Watt exercise, and spirometric data have been statistically evaluated in 152 patients with chronic obstructive bronchitis. In these patients, the hypoventilation syndrome increases during exercise. The correlation between age and PaO2 is identical during rest and exercise, but the correlation between PaO2 or PaCO2 and FEV1 (% predicted) is closer during exercise than during rest. The value 50 of the FEV1 (% predicted) divides the patients into two groups: the patients who stay normocapnic and those who become hypercapnic or increase their hypercapnemia. These data show the interest of the FEV1 (% predicted) values and allow to explain the evolution of the arterial blood gas tensions during exercise.

212 asthma patients, who attended their first health spa at La Bourboule, are studied. The functional data are statistically compared to those obtained from clinical examination. In this group of patients, it is found that: 1. Most of the functional tests are perturbed in proportion to the seiousness of the disease (determined by the number of days of attack per year). On the contrary, the other clinical criteria, and in particular the evolution time, do not affect the functional values. 2. The different ventilatory parameters studied are correlated two by two, for instance V 50 on the one had, FEV1, FEV1/VC or LR on the other. Finally the authors discuss the interest of V 50 and LR measurement in order to localize the bronchial obstruction in asthma at the level of either the large trunks (LR) or the small bronchii (V 50).

Two groups of patients with unilateral tuberculosis, either pulmonary (36 cases) or pleural (75 cases) were studied. The clinical and functional results were compared statistically. These two groups were similar in terms of age, sex, tobacco consumption, the radiological unilaterality of their disease and the global reduction of respiratory function (assessed by VC, FEV1, TPC and TLCO), which can be considered to be essentially due to the local disease. In both groups, the radiological image (extent of the lesion, shape of the lesion) is the only clinical factor statistically related to the functional values. The two groups differ in terms of two functional parameters which reflect different pathophysiological mechanisms in the affected lung. The group with pulmonary tuberculosis presents an obstructive ventilatory syndrome (reduction of the FEV1/VC ratio and increase in the RV/TPC ratio), which reflects the bronchial involvement in the disease. The group with pleural tuberculosis presents a pulmonary distention (increased RV/TPC ratio), which is related to disturbed transmission of the pleural pressure to ventilated alveolar zones. Secondly, in the group with pulmonary tuberculosis, the ventilation and perfusion deficits are equivalent, while in the pleural tuberculosis group, the ventilatory deficit is predominant. Thus the global reduction in ventilatory function which is the same in the two group is caused by fundamentally distinct pathophysiological mechanisms in the two groups of patients.