The aim of our study was to compare the short-term efficacy of three different chest physiotherapy (CPT) regimens (PD, postural drainage; PEP, positive expiratory pressure physiotherapy; HFCC, high-frequency chest compression physiotherapy) on patients with cystic fibrosis (CF) hospitalized for an acute pulmonary exacerbation. Sixteen patients with CF, 8 males, 8 females, aged 15-27 years (mean, 20.3 +/- 4), met the inclusion criteria: 1) age over 14 years; 2) mild or moderate airway obstruction; 3) sputum volume > 30 mL/day; 4) being proficient in PD and PEP CPT. Patients at admission had (mean +/- SD) forced volume in 1 second (FEV1) 52.2 +/- 21.9 percent predicted; Shwachman-Kulczycki clinical score 65.1 +/- 11 points; Chrispin-Norman chest radiography score 18.6 +/- 4.3 points. The three CPT regimens and a control-treatment (CONT) were administered in a random sequence, each patient receiving each treatment twice a day (in 50 minute sessions) for 2 consecutive days. During CONT and for 30 minutes after each session only spontaneous coughing was allowed. Wet and dry weight of sputum were recorded during the 50-minute sessions and 30 minutes afterward. Lung function was measured before and 30 minutes after each session. For each treatment a score was given by the patient for efficacy, and by both the patient and the physiotherapist for tolerance. Wet and dry weights of sputum collected during the sessions were greater for all CPT regimens than for CONT (P < 0.001, P < 0.0001). No significant differences between the three CPT regimens for both wet and dry weights were found when the number of coughs was taken into account.(ABSTRACT TRUNCATED AT 250 WORDS)

Transformation of erythronolide B to new antibiotics was attempted by feeding this compound during the fermentation of Streptomyces antibioticus ATCC 31771, a blocked mutant of an oleandomycin producing strain. As a result, four new active compounds were obtained with hybrid structures between erythromycin and oleandomycin. They were identified as 3-O-oleandrosyl-5-O-desosaminyl-15-hydroxyerythronolide B (I), 3-O-oleandrosyl-5-Odesosaminylerythronolide B (H), 3-O-oleandrosyl-5-O-desosaminyl-(8S)-8-hydroxyerythronolide B (III) and 3-O-oleandrosyl-5-O-desosaminyl-(8R)-8,19-epoxyerythronolide B (IV). They were found to be less active, but more stable to acid, than erythromycin A. From their relative biogenetical relationship together with the structure elucidated some hypotheses about late stages of oleandomycin biosynthesis are inferred too.

Following the previously described semisynthetic preparation of new aglycones (8S)-8fluoroerythronolide A (I), (8S)-8-fluoroerythronolide B (II) and the monoglycoside 3-0mycarosyl-(8S)-8-fluoroerythronolide B (III), their conversion into new fluoroerythromycins was attempted by mutational biosynthesis. The strain Streptomyces erythraeus ATCC 31772, a mutant blocked in the biosynthesis of erythromycin, was employed in the present investigation. Four new antibiotics, (8S)-8-fluoroerythromycin A (IV), (8S)-8-fluoroerythromycin B (V), (8S)-8-fluoroerythromycin C (VI) and (8S)-8-fluoroerythromycin D (VII) were successfully derived by such an approach. The result is also discussed in terms of the substrate specificity of the enzymes involved in the biosynthesis of erythromycins. The new antibiotics exhibited promising biological properties. During the last twenty years advances in organic fluorine chemistry have been responsible for the development of a large number of new compounds of importance in biology and medicine. Replacement of an atom of hydrogen by one of fluorine in organic molecules may profoundly change their biological properties','). The rationale employed is that, since hydrogen and fluorine are nearly isosteric, the fluoro analog would be expected to have little difficulty in fitting onto active sites of receptors. At the same time, the strong electronegativity of the fluorine atom, when strategically placed, could be used to make defined alterations in the biological activity.

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We have investigated the effectiveness of seven new beta-lactam antibiotics, azlocillin, piperacillin, ceftazidime, cefsulodin, cefoperazone, latamoxef (moxalactam), and cefotaxime, against acute pulmonary exacerbations caused by Pseudomonas aeruginosa in cystic fibrosis. Three hundred and fifty-five strains of Ps aeruginosa isolated from 310 sputum cultures (190 cystic fibrosis patients) were tested for susceptibility to the drugs by determination of minimal inhibitory concentrations (MIC). The highest activity was shown by ceftazidime (6% resistant strains) followed by cefsulodin and piperacillin (15 and 16% resistant strains); very low activity was found for cefotaxime and latamoxef (moxalactam). Ceftazidime was the most active drug against 32 pseudomonas isolates that were resistant to both carbenicillin and aminoglycosides (78% susceptible). A randomized, double-blind trial of azlocillin, piperacillin, ceftazidime, cefsulodin or cefoperazone was performed in 111 cystic fibrosis patients with predominant and susceptible pseudomonas in their sputum. Results were evaluated by a clinical, radiological and bacteriological scoring system: the best results were obtained with ceftazidime, followed by cefsulodin and piperacillin. However, pseudomonas was eradicated in only 22 (23%) of the cases with the most active drugs and persisted or reappeared in all the cases 1 to 3 months later. Ceftazidime always eradicated Staph. aureus and Haemophilus influenzae associated with pseudomonas. Similar eradication occurred nearly always with cefsulodin but rarely with the other drugs. No serious drug reaction occurred but a later fever and rash with piperacillin, transient diarrhoea with cefoperazone, vomiting with cefsulodin, and very frequent eosinophilia with ceftazidime should be mentioned. These five drugs offer, in varying degree, alternatives to traditional anti pseudomonas antibiotics in cystic fibrosis pulmonary infections, but they should be used only against well-proven resistant strains. Ceftazidime is best and cefotaxime and latamoxef (moxalactam) least useful.