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J F Lefebvre

Publications and source records attributed to J F Lefebvre.

46 records · Page 3Linked to original sources
PubMed1978

Morphological and cytochemical study of Chlamydia with EDTA regressive technique and Gautier staining in ultrathin frozen sections of infected cell cultures: a comparison with embedded material.

The cryo-ultramicrotomy technique was applied to study the ultrastructure of Chlamydia using two strains: one of C. psittaci and one of C. trachomatis. It clearly appeared that in both strains reticulate bodies show a high degree of plasticity, contrasting with the rigid spherical appearance of elementary bodies. Ultrastructural cytochemical study shows DNA fibrils dispersed throughout the cytoplasm in reticulate bodies whereas DNA is condensed in a nucleoid in elementary and intermediate bodies. The EDTA regressive technique reveals ribonucleoproteins in reticulate and elementary bodies of both studied strains.

Animals↗
PubMed1975

[Morphological ultrastructural and immunological studies of a rickettsia isolated from a parrot (author's transl)].

A rickettsia isolated from a parrot was found by use of electron microscopic and serological technic to be a Coxiella burneti. In cell culture one can see a dramatic polymorphism and a Gram negative-like structure of the cell wall. They divide by binary fission with no appearance of a complexe cycle of development like the one described for Chlamydia psittaci. Many myelinic fibrils and altered Coxiella suggest that the host cell react very deaply.

Animals↗
PubMedDate not supplied

[Percutaneous treatment of intrahepatic lithiasis].

AIM: To present our experience with percutaneous intracorporeal electrohydrolic lithotripsy in the treatment of intrahepatic lithiasis. SUBJECTS AND METHODS: From January 1989 to November 1998, 53 patients with intrahepatic lithiasis were treated with percutaneous intracorporeal electrohydrolic lithotripsy. Twenty-six patients had primary intrahepatic lithiasis. Intrahepatic stones were associated with intrahepatic duct abnormalities in 11 patients, 9 had strictures and 2 had cystic dilatations. Twenty-seven patients had secondary intrahepatic lithiasis formed a biliodigestive bypass in 20 patients. Intracorporeal electrohydrolic lithotripsy was performed under cholangioscopic guidance in all patients. The endoscope was introduced into the biliary ducts through a cutaneobiliary tract in 51 patients, through a cutaneocholecystic tract in one and through a cutaneojejunal tract in one. These tracts were created and gradually dilated in two sessions three days apart. In twenty-two patients stenosis or sharp angulation prevented adequate positioning of the scope which was only successful after balloon dilation or insertion of a stiff wire. RESULTS: Complete clearance of stones was achieved in 49 patients (92%). Biliary or hepaticojejunostomy strictures were successfully dilated with an angioplasty balloon in all patients. Ten patients (19%) had early complications: four had bilomas treated by percutaneous drainage, three had resolutive onset of cholangitis, two had transient arterial hemobilia, and one had a pneumothorax. The mean duration of follow-up was five years. During this period, 5 patients (9%) had recurrent symptoms of biliary obstruction. Among these patients, three (5.7%) had recurrent symptomatic intrahepatic lithiasis, one had a recurrent biliary stricture and one had secondary sclerosing cholangitis. Treatment of recurrent stones was repeated intracorporeal electrohydrolic lithotripsy in two and left hepatectomy in one; recurrent biliary stricture was treated by hepaticojejunostomy and secondary sclerosing cholangitis by antibiotics. CONCLUSION: Intracorporeal electrohydrolic lithotripsy is effective and safe and should be proposed as the first line treatment of primary or secondary intrahepatic lithiasis.

Adult↗
PubMedDate not supplied

[Kinetic study, in the mouse, of anti-chlamydia antibody formation: demonstration of target antigenic molecules].

A kinetic study of chlamydia antibody was performed in the C57BL/6 mouse to demonstrate whether some cell wall polypeptides could be useful in the detection of early infection. Polyacrylamide gel electrophoresis was employed, followed by electrophoretic transfer to nitrocellulose sheets of the polypeptides, separated according to their molecular weights. One polypeptide triplet appeared to be very interesting, that of 66, 65 and 64 Kd. The first two, and particularly the 65-Kd polypeptide, were determinant carriers which provoked an antibody response in the C57BL/6 mouse during an early phase of infection by the two species of chlamydia; the 65-Kd polypeptide reacted only with C. psittaci. The extension of this study to human disease was undertaken and preliminary results are encouraging; polypeptide markers of early infection in the C57BL/6 mouse, and especially that of 65 Kd, were revealed by the tested human sera and provoked the same type of response. A more extensive study in human species, in correlation with clinical observations, is currently being undertaken in our laboratory.

Animals↗
PubMedDate not supplied

[Polypeptidic composition analysis of "Chlamydia" purified elementary bodies by polyacrylamide slab gel electrophoresis (author's transl)].

The study of the polypeptidic components of elementary bodies of various strains of Chlamydia might help in the classification of these bacteria. The use of a satisfactory method for the preparation of purified elementary bodies has permitted the electrophoretic analysis of their crude lysate on polyacrylamide gel in the presence of sodium dodecyl sulfate. Differences between the strain LB 1 C. trachomatis and the strains Loth and MP 1 C. psittaci were found.

Cell Fractionation↗
PubMedDate not supplied

[Percutaneous treatment of malignant stenoses of the hilum].

PURPOSE: The endoscopic treatment of malignant hilar obstruction is followed in 70% of the case by infection of undrained biliary sectors. We report the influence of complete biliary drainage on post procedural cholangitis. METHOD: From January 1990 to January 1993 we treated 120 consecutive patients presenting with a malignant hilar obstruction. There were 61 women and 59 men, mean age 65 +/- 7.5 years. The level of stenosis was type II in 45 patients (37%), type III in 18 patients (13%) and above type III in 57 patients (48%). Complete biliary drainage with multiple biliary access was attempted in all patients. Long term internal drainage was achieved by metallic autoexpansive endoprosthesis. RESULTS: Complete drainage was achieved in all patients with type II or type III biliary stenosis. Drainage was incomplete in all patients with biliary stenosis above type III. Early complications were observed in 35% of the patients. Persistent cholangitis, the most frequent complication (22%) was only observed in patients with above type III biliary stenosis. Mortality at 30 days was 17%. Recurrent biliary obstruction was observed in 22% of the patients after an average of 187 days. Median survival was 95 days. CONCLUSION: Complete biliary drainage prevents persistent cholangitis in patients with type II or III biliary stenosis without increasing other complications related to biliary drainage.

Adult↗