Devenir des patientes atteintes de carcinome mammaire invasif apres radiotherapie adjuvante au Cameroun

Le cancer du sein est le premier des cancers tant dans les pays industrialises que dans plusieurs pays africains. Au Cameroun; son incidence est de 29; 7 /100000 personnes-annees et sa mortalite de 16;6 / 100000. Parmi les moyens therapeutiques; la radiotherapie adjuvante a un role non negligeable pour ameliorer la survie. Aussi avons-nous eu le desir de decrire le devenir des patientes atteintes de carcinome mammaire invasif apres radio-therapie adjuvante. Nous avons alors mene une etude retrospective de janvier 2006 a decembre 2010 dans les Services de Radiotherapie des Hopitaux Generaux de Yaounde et de Douala. Afin de determiner le devenir des patientes en termes de survie sans rechute et de survie globale. Nous avons egalement etabli les courbes de survie selon la methode de Kaplan-Meier et analyse les donnees a l'aide du logiciel Epi Info 3.5.3 .Les patientes avaient un age moyen de 46 ans; extremes de 22 a 80 ans. La survie sans rechute etait de 82;5 a 5 ans; les taux de rechute loco-regionale et a distance respectivement de 9;1 et de 18;8. Pour la survie globale; la survenue d'une rechute loco-regionale associee au stade tardif etait un facteur de mauvais pronostic (p = 0;009 et 0;047) tandis que la chirurgie conservatrice l'etait pour la survie sans recidive (p = 0;042). La radiotherapie adjuvante pratiquee au Cameroun pour le traitement des carcinomes mammaires invasifs ameliore le pronostic locoregional et de ce fait la survie globale

A rare prostatic diagnosis of an old man: a pure prostatic leiomyoma.

A pure leiomyoma of the prostate is a rare benign tumor. An 82-year-old man was referred to our urology department with gross hematuria and complete urinary retention. Examination revealed a benign prostatic hyperplasia. Transrectal ultrasound showed a prostate of 125 mL. Serum PSA was 1.9 µg/L. A simple retropubic prostatectomy was performed. Histopathological examination showed a pure leiomyoma of the prostate, without the presence of glandular prostate tissue. The diagnosis, characteristics, and treatment of this tumor are described.

Cross-protection between Actinobacillus pleuropneumoniae biotypes-serotypes in pigs.

Four groups of hysterectomy-derived and colostrum-deprived pigs were intranasally inoculated with an Actinobacillus pleuropneumoniae biotype 1-serotype 2 strain (producing RTX toxins ApxII and ApxIII. 6 pigs), an A. pleuropneumoniae biotype 1-serotype 10 strain (producing ApxI. 5 pigs), an A. pleuropneumoniae biotype 2-serotype 2 strain (producing ApxII, 5 pigs) or saline (controls, 7 pigs). All pigs were exposed to A. pleuropneumoniae biotype 1-serotype 2 endobronchial challenge. After challenge, severe clinical signs were observed in all control pigs, one pig immunized with the A. pleuropneumoniae biotype 1-serotype 10 strain and two pigs immunized with the A. pleuropneumoniae biotype 2-serotype 2 strain. These pigs died within 36 h after challenge and 20 to 50% of the lungs were macroscopically affected. In the other pigs, clinical signs were mild or absent and no or only small, focal lung lesions were observed when euthanized at 48 h after challenge. At the time challenge neutralizing antibodies against ApxI only. ApxII only and both ApxII and III were present in sera of pigs immunized with the A. pleuropneumoniae biotype 1-serotype 10 strain, the A. pleuropneumoniae biotype 2-serotype 2 strain and the A. pleuropneumoniae biotype 1-serotype 2 strain, respectively. These results indicate that immune mechanisms other than Apx neutralizing antibodies were involved in partial cross-protection of pigs immunized against A. pleuropneumoniae biotype 1-serotype 10 and challenged with the A. pleuropneumoniae biotype 1-serotype 2.

Knockout mutants of Actinobacillus pleuropneumoniae serotype 1 that are devoid of RTX toxins do not activate or kill porcine neutrophils.

The Actinobacillus pleuropneumoniae RTX-toxins ApxI, ApxII, and ApxIII are important virulence factors of this swine pathogen. It is hypothesized that the Apx toxins are deleterious to defense cells of the host, enabling the bacterium to infect the host. To confirm this, we studied the effect on porcine polymorphonuclear neutrophils of mutant strains of A. pleuropneumoniae that were devoid of Apx toxins. For this purpose, we developed a system for targeted mutagenesis of A. pleuropneumoniae based on the conditionally replicating plasmid pVE6063 and insertional mutagenesis by homologous recombination. Employing this system on the reference strain of serotype 1, a strain that secretes ApxI and ApxII, we generated mutant strains that were devoid of ApxI and/or ApxII. We compared the ability of the parent strain and the mutant strains to provoke an oxidative burst in porcine neutrophils and to kill these cells. The parent strain and mutants that secreted either ApxI or ApxII provoked an oxidative burst and killed the neutrophils, whereas mutant strains that were devoid of ApxI and ApxII did not. These experiments indicate the importance of ApxI and ApxII to these profound effects on neutrophils and emphasize the importance of ApxI and ApxII in pathogenesis.

Streptococcus suis infections in birds.

Four cases of Streptococcus suis infection were diagnosed in psittacine birds and four others in zebrafinches, bullfinches, canaries and a duck. The main clinical and pathological manifestation was septicaemia with multiple sudden deaths in nestlings, young and adults. Other cases were solitary, with evidence for secondary involvement of S. suis. Four serotypable strains all belonged to serotype 9.

Chemiluminescence properties of porcine pulmonary alveolar macrophages and polymorphonuclear cells.

A luminol-enhanced chemiluminescence (CL) technique was developed for porcine pulmonary alveolar macrophages (PAM) and polymorphonuclear cells (PMN). PAM were obtained from lung washings of 3 week old gnotobiotic pigs. PMN were obtained from peripheral blood by separation on a discontinuous Percoll gradient. Optimum CL signals were obtained with 10(5) PAM/tube and 5 x 10(4) PMN/tube. Stimulation indexes (SI) for PAM were approximately 10 for phorbol myristate acetate (PMA), 8 for opsonized Actinobacillus pleuropneumoniae and 3 for opsonized zymosan. SI for PMN varied from 100 to 180 for complement opsonized zymosan, from 50 to 100 for opsonized A. pleuropneumoniae and from 10 to 20 for PMA. Formyl-methionyl-phenylalanine and calcium ionophore A23187 did not stimulate the oxidative activity of PAM or PMN. PAM that had been frozen and stored in liquid nitrogen reacted as freshly obtained PAM in the CL assay; however, PMN that had been frozen lost a great deal of their ability to produce oxygen radicals after thawing. The CL technique offers new perspectives for the study of immune mechanisms in swine.

NAD-independent Actinobacillus pleuropneumoniae strains: production of RTX toxins and interactions with porcine phagocytes.

Actinobacillus pleuropneumoniae RTX toxin (Apx) production by A. pleuropneumoniae biotype 2 (NAD-independent) serotype 2 strains was studied. Western blot analysis of culture supernatants of all biotype 2 strains tested revealed the presence of a 103 kDa protein which reacted with a monoclonal antibody against ApxIIA. This protein was also recognized by sera of pigs infected with a biotype 2-serotype 2 strain. Furthermore, antibodies that could neutralize ApxIIA were present in these sera. Proteins corresponding to ApxIA or ApxIIIA were not detected. The effects of a biotype 1-serotype 2 and a biotype 2-serotype 2 strain and their metabolites on the oxidative activity of porcine pulmonary alveolar macrophages (PAM) and polymorphonuclear cells (PMN) were compared using a chemiluminescence (CL) technique. Viable bacteria of both biotypes stimulated the production of oxygen radicals by phagocytes. CL responses were higher for the biotype 1 than for the biotype 2 strain. After having reached a peak value, the oxidative activity decreased until a total inhibition was achieved. Inactivated washed bacteria had no influence on the oxidative activity of phagocytes. In contrast, heat labile factors in culture supernatants of both biotypes stimulated and inhibited the oxidative activity of PAM in a dose-dependent manner. Dilutions of supernatant up to 1/32 of the biotype 2 strain and up to 1/512 of the biotype 1 strain were toxic for PAM, while dilutions from 1/64 to 1/128 of the biotype 2 strain and from 1/1024 to 1/4096 of the biotype 1 strain stimulated the oxidative activity.(ABSTRACT TRUNCATED AT 250 WORDS)

In vivo association of Actinobacillus pleuropneumoniae serotype 2 with the respiratory epithelium of pigs.

The ability of an Actinobacillus pleuropneumoniae serotype 2 strain to associate in vivo with the epithelium of the porcine respiratory tract was investigated in a sequential study after intranasal inoculation of hysterectomy-derived and colostrum-deprived pigs. At 30 min postinoculation more than 95% of the bacteria present in the lungs were intimately associated with the epithelium of the alveoli or the cilia of the terminal bronchioli, as observed by light and electron microscopy. At 90 and 180 min postinoculation multiple focal early inflammatory lesions in which histologically different, more or less concentric zones could be distinguished were observed. In the center of these pneumonic areas bacteria were associated with infiltrated cells and exudate. In the zone surrounding the center, approximately 95% of the bacteria were lying with their longest side in close apposition to the epithelial cells of alveoli and the cilia of the terminal bronchioli. Bacteria were only sporadically associated with the cilia or the epithelium of the bronchi and trachea. Bacteria were not observed in tonsils or conchae. In view of the findings presented here, we propose the hypothesis that adherence of the A. pleuropneumoniae serotype 2 strain to epithelial cells of the lower respiratory tract constitutes an important initial step in pathogenesis.

Serotyping and quantitative determination of in vitro antibiotic susceptibility of Actinobacillus pleuropneumoniae strains isolated in Belgium (July 1991-August 1992).

One hundred and ninety nine Actinobacillus pleuropneumoniae isolates obtained from the respiratory tract of pigs in Belgium (1991-1992) were serotyped using slide agglutination and slide precipitation tests. Biotype 1-serotype 2 and 3 strains were isolated most frequently and represented 36% and 21% of the isolates, respectively. Serotype 9 and serotype 5B strains represented 15% and 10% of the total number of isolates, respectively, while serotypes 7, 8, 10 and 11 were isolated only sporadically. Serotypes 5B, 10 and 11 were isolated for the first time in Belgium. Biotype 2 strains represented 12.5% of the total number and all belonged to the serotype 2. The in vitro susceptibility of 138 strains was determined for ten commonly used antibiotics. For three antibiotics, ampicillin, chloramphenicol, and oxytetracycline, a bimodal distribution of strain sensitivities was observed. A total of 17 strains (12%) were considered to have acquired resistance to one or more of these antibiotics.

Pathogenic staphylococci and staphylococcal infections in canaries.

Staphylococcus aureus was isolated from six cases of bacterial infection in canaries, Staphylococcus hyicus from three and Staphylococcus intermedius from one case. Staphylococcus aureus was most often involved in outbreaks of septicaemia, with or without 'Megabacterium' proventriculitis. The other coccal species were mainly complicating disease caused by Atoxoplasma (Lankesterella), Chlamydia psittaci and canary pox.

Papillomavirus-like infections in canaries (Serinus canarius).

A papillomavirus-like infection in canaries (Serinus canarius) is described. Papillomatous epithelial proliferations were observed at the commissure of the beak and on the head. Histologically, stratified squamous epithelium covered with a hyperkeratotic layer and intranuclear inclusions were observed. Electron microscopically, intranuclear aggregates of papilloma-like virus particles were demonstrated.

Influence of Actinobacillus pleuropneumoniae serotype 2 and its cytolysins on porcine neutrophil chemiluminescence.

The effects of Actinobacillus pleuropneumoniae serotype 2 and its metabolites on the oxidative activity of porcine neutrophils were studied by using a chemiluminescence technique. Viable A. pleuropneumoniae stimulated the production of oxygen radicals by neutrophils. After having reached a peak value, the oxidative activity decreased until a total inhibition of the oxidative activity of the neutrophils was achieved. All effects were neutralized with homologous convalescent-phase pig sera which had been adsorbed by heat-inactivated A. pleuropneumoniae. Inactivated bacteria and bacteria in the presence of chloramphenicol each had no influence on the oxidative activity of neutrophils. In contrast, a heat-labile factor in A. pleuropneumoniae culture supernatants stimulated and inhibited the oxidative activity of the neutrophils in a dose-dependent manner. Undiluted and low dilutions of culture supernatants were toxic for the phagocytes, while high dilutions stimulated the oxygen radical production of the neutrophils. These effects were neutralized with homologous convalescent-phase pig sera. In order to investigate whether the heat-labile factors in the culture supernatant could be cytolysins, we repeated the experiments with cytolysin II and cytolysin III produced by recombinant Escherichia coli. It was demonstrated that stimulation and inhibition could be reproduced by both cytolysins. In conclusion, the observations made in this study showed that A. pleuropneumoniae secretes heat-labile metabolites that stimulate neutrophil-oxidative metabolism at relatively low concentrations and kill the neutrophils at higher concentrations. Cytolysins may be responsible, at least in part, for these effects.

Staphylococcus hyicus associated with pox in chickens and in turkeys.

Staphylococcus hyicus was isolated in profuse and often pure culture from skin lesions, and from internal organs of chickens and turkeys suffering from pox. Most cases were seen in backyard stock, but similar observations were made in laying hens from an industrial farm.

Stimulation and suppression of the oxygenation activity of porcine pulmonary alveolar macrophages by Actinobacillus pleuropneumoniae and its metabolites.

The effects of Actinobacillus (Haemophilus) pleuropneumoniae and its metabolites on the oxygenation activity of porcine pulmonary alveolar macrophages (PAM) were studied, using a chemiluminescence technique. Actinobacillus pleuropneumoniae strains of serotypes 2, 3, and 9 in a dose of 1, 10, and 100 colony-forming units/macrophage first stimulated the oxygen radical production of PAM. After having reached a peak value, oxygenation activity decreased, finally resulting in total suppression of PAM. All these effects were neutralized by homologous convalescent pig sera that had been adsorbed onto inactivated A pleuropneumoniae strains. Moreover, cross-neutralization was shown between serotypes 2 and 3. Inactivated A pleuropneumoniae strains did not influence the oxidative activity of PAM. Undiluted and lower dilutions of sterile A pleuropneumoniae culture supernatants were toxic for PAM, whereas higher dilutions of the supernatants stimulated oxygen radical production of the macrophages. These effects were heat-sensitive and were neutralized by homologous convalescent pig sera. Cross-neutralization was shown between serotypes 2 and 3. These findings indicated that stimulation and inhibition of the oxygenation activity of PAM are attributable to heat-sensitive metabolites produced by A pleuropneumoniae.

Comparative virulence of NAD-dependent and NAD-independent Actinobacillus pleuropneumoniae strains.

The virulence of a NAD-independent Actinobacillus pleuropneumoniae serotype 2 strain and NAD-dependent serotype 2, 3 and 9 strains was compared under experimental conditions. Hysterectomy-derived piglets were inoculated endobronchially with 50-500 cfu of these strains. All 23 piglets inoculated with the NAD-dependent strains developed acute disease within 12 hours post inoculation. Twenty-two of these piglets died within 24 hours after the first clinical signs. Three of nine piglets inoculated with the NAD-independent strain did not develop clinical disease. In the other six piglets, disease signs were similar as in the piglets inoculated with the NAD-dependent strains. No differences in clinical disease were observed between colostrum deprived piglets and piglets that obtained colostrum from a SPF sow.

Prevalence of Leptospira interrogans serovar hardjo antibodies in milk in Belgian dairy herds.

Pooled milk samples were collected from 2000 Belgian dairy herds in the autumn of 1989. Antibodies against Leptospira interrogans serovar hardjo were detected in 9.2% of the herds, with the incidence being higher in the southern part of the country.