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P Allouch

Publications and source records attributed to P Allouch.

30 records · Page 2Linked to original sources

ATR-FTIR spectroscopic investigation of imipenem-susceptible and -resistant Pseudomonas aeruginosa isogenic strains.

The primary mechanism of imipenem resistance in Pseudomonas aeruginosa has been ascribed to an outer membrane impermeability owing to a loss of expression of protein D2. Attenuated total reflection-Fourier transform infrared spectroscopy in conjunction with statistical methods has been used as a new approach to rapidly discriminate four isogenic strains of P. aeruginosa--susceptible, less susceptible, and highly resistant to imipenem-- and to follow the structural modifications related to this low permeability. Decomposition of the broad protein and carbohydrate contours into underlying Gaussians and comparison of the susceptible and highly resistant strain provided quantitative and ultrastructural information on these strains. This methodology allows for discrimination not of the mutation itself but of its consequences observed in the protein and carbohydrate absorption regions. Its association with other existing biochemical methods may be envisaged since it may allow for rapid orientation of investigations in the field of bacterial resistance diagnosis.

Bacterial Outer Membrane Proteins↗

Pharmacokinetics and bactericidal activities of one 800-milligram dose versus two 400-milligram doses of intravenously administered pefloxacin in healthy volunteers.

Pefloxacin pharmacokinetics and serum bactericidal activities (SBA) against Escherichia coli and Staphylococcus aureus were compared after intravenous infusion of either a single 800-mg dose or twice-daily 400-mg doses into 16 healthy volunteers. Plasma pefloxacin concentrations were measured for up to 60 h, and SBAs were determined 1, 12, and 24 h after the start of the infusion. The mean areas under the concentration-versus-time curve for plasma were not different (138 versus 136 h.mg/liter). The mean clearances, volumes of distribution, and half-lives were also comparable. The mean (+/- standard deviation) maximal concentration after the 800-mg infusion was 12.11 +/- 1.35 versus 6.51 +/- 0.73 mg/liter after the first 400-mg infusion and 7.42 +/- 0.76 mg/liter after the second 400-mg infusion. Mean trough concentrations at 24 h were significantly different: 2.77 +/- 0.63 (800 mg) versus 1.93 +/- 0.49 (400 mg twice) mg/liter (P = 0.0007). Mean SBAs against E. coli after 800 mg of pefloxacin were higher than 1/128 (1 h), 1/32 (12 h), and 1/16 (24 h). Mean SBAs against S. aureus under the same conditions were higher than 1/64 (1 h), 1/16 (12 h), and 1/8 (24 h). Mean SBAs at 1 and 12 h were significantly higher after the 800-mg infusion than after the 400-mg infusion but were similar at 24 h for both regimens. Comparison of SBAs according to National Committee for Clinical Laboratory Standards criteria showed a similar adequacy at 24 h for both regimens against both strains. Administration of 800 mg of pefloxacin once a day is bioequivalent to 400 mg twice a day, and bactericidal activity of the 800-mg infusion is not less than that of two 400-mg infusions.

Adult↗

[Frequency and distribution of beta-lactamases in 1792 strains of Klebsiella pneumoniae in France between 1985 and 1988].

In october 1985, 1987 and 1988, all the clinical isolates of K. pneumoniae (respectively 530, 654, 590 strains) were collected in 20 hospitals. The beta-lactamases were identified by analytical isoelectrofocusing and by substrate and inhibition profiles. 76 to 81% of the strains produced only one beta-lactamase: SHV-1 type, pI 7.7 (61 to 65%) or PI 7.1 (14%). The TEM-1 betalactamase (pI 5.4) was produced in 1985 by 21% of the strains, 9% in 1987, and 11% in 1988: TEM-2, pI 5.6 by 2% in 1985-87-88. The extended broad spectrum beta-lactamases, able to hydrolyse amino-thiazol-oximino-beta-lactam antibiotics, TEM or SHV type enzymes (SHV-2, pI 7.7, SHV-3, pI 7.1; SHV-4/CAZ-5, pI 7.8; SHV-5/CAZ-4 pI 8.2; CTX-1/TEM-3, pI 6.3) were also detected: 0.75% of the strain (3 strains) in 1985, 8.4% (55 strains) in 1987, 11% (65 strains) in 1988. These extended broad spectrum beta-lactamases were found in 2 hospitals in 1985, 10 in 1987 and 9 in 1988.

France↗

[Antibiotherapy in biliary surgery. Current status].

Without antibiotherapy, biliary surgery is often followed by infectious complications, possibly serious, indeed life-threatening. Biliary bacteria do are responsible of these complications; mainly E. Coli, Streptococcus faecalis (whose pathogenicity is disputed) and Klebsiella. Bacteroides fragilis and Pseudomonas aeruginosa are restricted to special circumstances. It is often difficult to presee whether bile is infected: some risk factors were emerged by Keighley but their specificity is not excellent; peroperative Gram staining got various results according to the studies. Some prefer to give a systematic antibiotherapy. Preoperative antibiotic treatment should be as short as possible because it does not sterilize bile, but selects resistant bacteria, which induce postoperative complications. It must mainly be aimed at preventing infectious scattering. Surgery is the main part of the treatment. Antibiotic choice has to take into account clinical picture, bacteria (those probably responsible for and their sensibility) and goal of the treatment (prophylactic or curative). Analysis of failures should allow to improve this choice. But only multicenter studies concerning full selected populations of patients are able to prove superiority of one antibiotic to another.

Abscess↗

[Multicenter study of the sensitivity to beta-lactam antibiotics of 1,707 strains of Pseudomonas aeruginosa isolated at a general hospital].

1,707 non replicate clinical strains of Pseudomonas aeruginosa from non teaching hospitals were investigated. Beta-lactam antibiotics were tested by agar disk diffusion method. Variance analysis revealed a significant interaction between strains and experimental laboratories. The bacterial population was grouped according to the diameters of inhibition zones of antibiogram, into five phenotypes. Pseudomonas aeruginosa is frequently isolated from urines and pulmonary sampling, rarely from blood cultures. Resistance to beta-lactams increased significantly with the duration of hospitalisation, and age of patients. Clinical strains are significantly more resistant in blood cultures, and for strains isolated from reanimation. 84% of strains are susceptible to ticarcillin.

Adolescent↗

[Bacteriology of the bile ducts and antibiotic prophylaxis].

The gallbladder wall, gallbladder lumen and bile duct intraoperative sampling materials had been examined in 52 patients with an operation on the biliary tract. All patients were treated by only one infusion before operation: 1 g ceftriaxone was given to 26 patients and 2 g ceftriaxone to the 26 others. Bacterial species were isolated on twenty patients. There was no significant difference in infection rate and organism identity between bacterial flora isolated from patients receiving 1 g ceftriaxone and patients receiving 2 g. Isolated germs were enterobacteriaceae (15) streptococci (14) and anaerobic bacteria (8). The mean count of bacteria in bile is 10(4) germs/ml. Half positive sampling materials contains more than one bacterial strain. The bacterial flora isolated from bile has characteristics of mixed flora infection. Ceftriaxone had a good efficacy in antibiotic prophylaxis.

Adult↗

[Prophylactic antibiotherapy in biliary surgery, cefazolin versus cefoperazone. Randomized comparative open study in a population at risk for infection].

Sixty patients having to undergo a biliary operation with high risk of infection (Keighley's criterions) received at random either cefazolin (CFZ) or cefoperazone (CFP) as a prophylactic antibiotherapy. Postoperative courses were fairly normal: a peak of temperature on day 5 for one case and a digestive bleeding due to hypoprothrombinemia for another case. No further complication occurred. Patient discharge was two days shorter with cefoperazone and biliary positive cultures were in favour of cefoperazone (21% with CFZ, 11% with CFP) but without statistically significant level. Consequently, this trial should be carried out on a larger scale.

Adolescent↗

[Detection of circulating Candida albicans mannan and antimannan antibodies: useful for diagnosis of deep seated candidiasis].

In deep seated candidiasis, only 40% of blood cultures are positive. The aim of the study was to investigate circulating Candida albicans mannan and anti-mannan antibodies as a possible help for the diagnosis of deep seated candidiasis. We have compared the results to the detection of IgM by Elisa and antibodies by immunoflourescence. The best tests, in accord to their sensitivity and specificity, are the mannan antigenemia (43% and 100%) and IgM (86% and 100%) and have to be used together.

Antibodies, Fungal↗