25 research outputs found
Reproductive performance of native and imported dairy cows in the Tadla region (Morocco)
Parmi les performances de reproduction des vaches laitiĂšres dans la rĂ©gion du Tadla (Maroc) sur une pĂ©riode de 4 annĂ©es, lâĂąge Ă la premiĂšre insĂ©mination artificielle (IA) a Ă©tĂ© de 573,4 ± 35,6 jours et Ă lâĂąge au premier vĂȘlage de 853,8 ± 103,5 jours, lâintervalle vĂȘlage-1Ăšre IA de 75,5 ± 35,6 jours. Celui-ci a Ă©tĂ© plus court chez les femelles importĂ©es que chez les natives. La race MontbĂ©liarde a Ă©tĂ© insĂ©minĂ©e plus tĂŽt que la race PrimâHolstein. Le taux de rĂ©ussite en 1Ăšre IA a Ă©tĂ© de 53,2% avec de larges variations inter-annuelles et inter-Ă©levages. Les Primâholstein ont Ă©tĂ© mieux fĂ©condĂ©es que les autres races. 18,2% des vaches ont nĂ©cessitĂ© 3 IA ou plus et lâindice coĂŻtal a Ă©tĂ© de 1,8 ±1,3. La campagne, lâĂ©levage et la race ont affectĂ© significativement le taux de femelles ayant nĂ©cessitĂ© 3 IA ou plus. La race Primâholstein française a manifestĂ© un taux infĂ©rieur Ă celui de la race Primâholstein canadienne. Lâintervalle vĂȘlage - insĂ©mination fĂ©condante a Ă©tĂ© de 119,2 ± 83,8 jours. Ce paramĂštre a variĂ© trĂšs significativement selon lâannĂ©e, lâĂ©levage, la race et le numĂ©ro de lactation. La race MontbĂ©liarde a prĂ©sentĂ© undĂ©lai moyen de fĂ©condation plus court que la race PrimâHolstein Canadienne
Evaluation of transduction efficiency in macrophage colony-stimulating factor differentiated human macrophages using HIV-1 based lentiviral vectors
<p>Abstract</p> <p>Background</p> <p>Monocyte-derived macrophages contribute to atherosclerotic plaque formation. Therefore, manipulating macrophage function could have significant therapeutic value. The objective of this study was to determine transduction efficiency of two HIV-based lentiviral vector configurations as delivery systems for the transduction of primary human blood monocyte-derived macrophages.</p> <p>Results</p> <p>Human blood monocytes were transduced using two VSV-G pseudotyped HIV-1 based lentiviral vectors containing EGFP expression driven by either native HIV-LTR (VRX494) or EF1α promoters (VRX1090). Lentiviral vectors were added to cultured macrophages at different times and multiplicities of infection (MOI). Transduction efficiency was assessed using fluorescence microscopy and flow cytometry. Macrophages transduced between 2 and 120 hours after culturing showed the highest transduction efficiency at 2-hours transduction time. Subsequently, cells were transduced 2 hours after culturing at various vector concentrations (MOIs of 5, 10, 25 and 50) to determine the amount of lentiviral vector particles required to maximally transduce human monocyte-derived macrophages. On day 7, all transduced cultures showed EGFP-positive cells by microscopy. Flow cytometric analysis showed with all MOIs a peak shift corresponding to the presence of EGFP-positive cells. For VRX494, transduction efficiency was maximal at an MOI of 25 to 50 and ranged between 58 and 67%. For VRX1090, transduction efficiency was maximal at an MOI of 10 and ranged between 80 and 90%. Thus, transductions performed with VRX1090 showed a higher number of EGFP-positive cells than VRX494.</p> <p>Conclusions</p> <p>This report shows that VSV-G pseudotyped HIV-based lentiviral vectors can efficiently transduce human blood monocyte-derived macrophages early during differentiation using low particle numbers that do not interfere with differentiation of monocytes into macrophages.</p