Influence de la saison et de la concentration énergétique de l'aliment sur les performances de croissance de pintadeaux (<em>Numida meleagris</em>) en région tropicale

Deux expériences de croissance de pintadeaux de chair ont été réalisées durant 15 semaines au Sénégal. La première expérience a été conduite en saison sèche sur 198 pintadeaux répartis en 2 lots subdivisés chacun en 3 répétitions de 33 animaux. Pendant les périodes de démarrage, de croissance et de finition, les lots ont été nourris avec deux types d'aliments : 2 550 kcal/kg pour les aliments " basse énergie " (BE) et 2 800 kcal/kg pour les aliments " témoins " (T). La seconde expérience a été conduite en saison pluvieuse en respectant un protocole expérimental identique. Au cours de la saison sèche, le poids vif moyen à 15 semaines de 1 805 g pour le lot T a été significativement plus faible pour le lot BE avec un écart de 412 g entre les deux régimes. En saison des pluies, les poids vifs moyens à 15 semaines étaient significativement inférieurs : respectivement - 488 et - 274 g pour les lots T et BE en comparaison des performances enregistrées en saison sèche. La différence de poids vif enregistrée entre les régimes T et BE était significative pendant cette saison, mais elle s'élevait seulement à 198 g. La consommation d'aliments a été significativement plus élevée pour le lot T pendant les deux saisons (différence de 18 g par jour en saison sèche et de 8 g par jour en saison pluvieuse). Aucune différence significative n'a été mise en évidence entre les deux lots pour l'indice de consommation, mais celui-ci était significativement plus élevé pendant la saison pluvieuse (5,3 contre 4,5 pendant la saison sèche). Aucune mortalité n'a été observée pendant les deux expériences

Alveolar fluid in acute respiratory distress syndrome promotes fibroblast migration: role of platelet-derived growth factor pathway

OBJECTIVES: Fibroblast migration is an initiating step in fibroproliferation; its involvement during acute lung injury and acute respiratory distress syndrome remains poorly understood. The aims of this study were: 1) to determine whether bronchoalveolar lavage fluids from patients with acute lung injury/acute respiratory distress syndrome modulate lung fibroblast migration; 2) to assess lung fibroblast migration\u27s clinical relevance; and 3) to evaluate the role of the platelet-derived growth factor pathway in this effect. DESIGN: Prospective cohort study. SETTING: Three intensive care units of a large tertiary referral center. PATIENTS: Ninety-three ventilated patients requiring bronchoalveolar lavage fluids were enrolled (48 with acute respiratory distress syndrome, 33 with acute lung injury, and 12 ventilated patients without acute lung injury/acute respiratory distress syndrome). INTERVENTIONS: After bronchoalveolar lavage fluids collection during standard care, the patients were followed up for 28 days and clinical outcomes were recorded. Migration assays were performed by using a Transwell model; bronchoalveolar lavage fluids platelet-derived growth factor and soluble platelet-derived growth factor receptor-alpha were characterized by Western blot and measured by ELISA. MEASUREMENTS AND MAIN RESULTS: Most of the bronchoalveolar lavage fluids inhibited basal fibroblast migration. Bronchoalveolar lavage fluids chemotactic index increased with severity of lung injury (28% in patients without acute lung injury/acute respiratory distress syndrome and with acute lung injury vs. 91% in acute respiratory distress syndrome patients; p = .016). In acute lung injury/acute respiratory distress syndrome patients, inhibition of basal fibroblast migration by bronchoalveolar lavage fluids below 52% was independently associated with a lower 28-day mortality (odds ratio [95% confidence interval] 0.313 [0.10-0.98], p = .046). Platelet-derived growth factor-related peptides and soluble platelet-derived growth factor-Ralpha were detected in all bronchoalveolar lavage fluids from acute lung injury/acute respiratory distress syndrome patients. The effect of bronchoalveolar lavage fluids stimulating migration was inhibited by a specific platelet-derived growth factor receptor inhibitor (AG1296). Bronchoalveolar lavage fluids inhibiting migration reversed the effect of rh-platelet-derived growth factor-BB and reduced by 40% the binding of 125I-platelet-derived growth factor-BB to fibroblast cell surface in favor of a role for platelet-derived growth factor-sRalpha. CONCLUSIONS: : Together, our results suggest that during acute lung injury, fibroblast migration is modulated by bronchoalveolar lavage fluids through a platelet-derived growth factor/platelet-derived growth factor-sRalpha balance. Migration is associated with clinical severity and patient 28-day mortality

Hepatocyte and keratinocyte growth factors and their receptors in human lung emphysema

BACKGROUND: Hepatocyte and keratinocyte growth factors are key growth factors in the process of alveolar repair. We hypothesized that excessive alveolar destruction observed in lung emphysema involves impaired expression of hepatocyte and keratinocyte growth factors or their respective receptors, c-met and keratinocyte growth factor receptor. The aim of our study was to compare the expression of hepatocyte and keratinocyte growth factors and their receptors in lung samples from 3 groups of patients: emphysema; smokers without emphysema and non-smokers without emphysema. METHODS: Hepatocyte and keratinocyte growth factor proteins were analysed by immunoassay and western blot; mRNA expression was measured by real time quantitative polymerase chain reaction. RESULTS: Hepatocyte and keratinocyte growth factors, c-met and keratinocyte growth factor receptor mRNA levels were similar in emphysema and non-emphysema patients. Hepatocyte growth factor mRNA correlated negatively with FEV1 and the FEV1/FVC ratio both in emphysema patients and in smokers with or without emphysema. Hepatocyte and keratinocyte growth factor protein concentrations were similar in all patients' groups. CONCLUSION: The expression of hepatocyte and keratinocyte growth factors and their receptors is preserved in patients with lung emphysema as compared to patients without emphysema. Hepatocyte growth factor mRNA correlates with the severity of airflow obstruction in smokers

SNARE Protein Mimicry by an Intracellular Bacterium

Many intracellular pathogens rely on host cell membrane compartments for their survival. The strategies they have developed to subvert intracellular trafficking are often unknown, and SNARE proteins, which are essential for membrane fusion, are possible targets. The obligate intracellular bacteria Chlamydia replicate within an intracellular vacuole, termed an inclusion. A large family of bacterial proteins is inserted in the inclusion membrane, and the role of these inclusion proteins is mostly unknown. Here we identify SNARE-like motifs in the inclusion protein IncA, which are conserved among most Chlamydia species. We show that IncA can bind directly to several host SNARE proteins. A subset of SNAREs is specifically recruited to the immediate vicinity of the inclusion membrane, and their accumulation is reduced around inclusions that lack IncA, demonstrating that IncA plays a predominant role in SNARE recruitment. However, interaction with the SNARE machinery is probably not restricted to IncA as at least another inclusion protein shows similarities with SNARE motifs and can interact with SNAREs. We modelled IncA's association with host SNAREs. The analysis of intermolecular contacts showed that the IncA SNARE-like motif can make specific interactions with host SNARE motifs similar to those found in a bona fide SNARE complex. Moreover, point mutations in the central layer of IncA SNARE-like motifs resulted in the loss of binding to host SNAREs. Altogether, our data demonstrate for the first time mimicry of the SNARE motif by a bacterium

Is adenomyosis the neglected phenotype of an endomyometrial dysfunction syndrome?

Since the dissociation between adenomyoma and endometriosis in the 1920s and the laparoscopic progress in the diagnosis and surgery of endometriosis, the literature has been greatly focused on the disease endometriosis. The study of adenomyosis, on the other hand, has been neglected as the diagnosis remained based on hysterectomy specimens. However, since the introduction of magnetic resonance and sonographic imaging techniques in the 1980s, the myometrial junctional zone has been identified as a third uterine zone and interest in adenomyosis was renewed. This has also been the start for the interest in the role of the myometrial junctional zone dysfunction and adenomyosis in reproductive and obstetrical disorders

Multi-genome identification and characterization of chlamydiae-specific type III secretion substrates: the Inc proteins

<p>Abstract</p> <p>Background</p> <p><it>Chlamydiae </it>are obligate intracellular bacteria that multiply in a vacuolar compartment, the inclusion. Several chlamydial proteins containing a bilobal hydrophobic domain are translocated by a type III secretion (TTS) mechanism into the inclusion membrane. They form the family of Inc proteins, which is specific to this phylum. Based on their localization, Inc proteins likely play important roles in the interactions between the microbe and the host. In this paper we sought to identify and analyze, using bioinformatics tools, all putative Inc proteins in published chlamydial genomes, including an environmental species.</p> <p>Results</p> <p>Inc proteins contain at least one bilobal hydrophobic domain made of two transmembrane helices separated by a loop of less than 30 amino acids. Using bioinformatics tools we identified 537 putative Inc proteins across seven chlamydial proteomes. The amino-terminal segment of the putative Inc proteins was recognized as a functional TTS signal in 90% of the <it>C. trachomatis </it>and <it>C. pneumoniae </it>sequences tested, validating the data obtained <it>in silico</it>. We identified a <it>macro </it>domain in several putative Inc proteins, and observed that Inc proteins are enriched in segments predicted to form coiled coils. A surprisingly large proportion of the putative Inc proteins are not constitutively translocated to the inclusion membrane in culture conditions.</p> <p>Conclusions</p> <p>The Inc proteins represent 7 to 10% of each proteome and show a great degree of sequence diversity between species. The abundance of segments with a high probability for coiled coil conformation in Inc proteins support the hypothesis that they interact with host proteins. While the large majority of Inc proteins possess a functional TTS signal, less than half may be constitutively translocated to the inclusion surface in some species. This suggests the novel finding that translocation of Inc proteins may be regulated by as-yet undetermined mechanisms.</p

Premiers aspects de la création métayage au Gabon

First aspects of the creation of a bovine rural stockfarming through a sharecropping system in Gabon. In the same time that the country develops great bovine production complexes, a project has been created to diffuse cattle by sharecropping in rural environment. Material and technical conditions are prescribed to new breeders before they receive as a loan some animals of the race N'dama, starting point of a future herd