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91.
Narcis B. Kabatereine Mwele Malecela Mounir Lado Sam Zaramba Olga Amiel Jan H. Kolaczinski 《PLoS neglected tropical diseases》2010,4(6)
Combining the delivery of multiple health interventions has the potential to minimize costs and expand intervention coverage. Integration of mass drug administration is therefore being encouraged for delivery of preventive chemotherapy (PCT) to control onchocerciasis, lymphatic filariasis, schistosomiasis, soil-transmitted helminthiasis, and trachoma in sub-Saharan Africa, as there is considerable geographical overlap of these neglected tropical diseases (NTDs). With only a handful of countries having embarked on integrated NTD control, experience on how to develop and implement an efficient integrated programme is limited. Historically, national and global programmes were focused on the control of only one disease, usually through a comprehensive approach that involved several interventions including PCT. Overcoming the resulting disease-specific structures and thinking, and ensuring that the integrated programme is embedded within the existing health structures, pose considerable challenges to policy makers and implementers wishing to embark on integrated NTD control. By sharing experiences from Uganda, Tanzania, Southern Sudan, and Mozambique, this symposium article aims to outlines key challenges and solutions to assist countries in establishing efficient integrated NTD programmes. 相似文献
92.
Lado C Then M Varga I Szoke E Szentmihályi K 《Zeitschrift für Naturforschung. C, Journal of biosciences》2004,59(5-6):354-358
Some current oils and their main components were studied to determine their antioxidant values. This was done by using the modified method of ferric reducing ability of plasma. It has been established that volatile oils of medicinal plants have on average a reducing capacity of 3.5-220 mmol/kg oil. The reducing capacities of the main constituents of volatile oils are 0.165-65.5 mmol/kg in concentrated oils. The highest reducing capacity was showd for phellandrene (65.438 +/- 0.166 mmol/kg) and anethole (50.087 +/- 0.160 mmol/kg) while the lowest values were obtained for menthol (0.165 +/- 0.023 mmol/kg) and menthone (0.168 +/- 0.010 mmol/kg). It has been stated that the antioxidant values of the main constituents are lower than those of volatile oils. The reducing capacity of the main constituents of medicinal plant drugs at different concentrations was also determined. 相似文献
93.
The plasma membrane Ca(2+)-ATPase was purified from Arabidopsis thaliana cultured cells by calmodulin (CaM)-affinity chromatography and reconstituted in proteoliposomes by the freeze-thaw sonication procedure. The reconstituted enzyme catalyzed CaM-stimulated 45Ca(2+) accumulation and H(+) ejection, monitored by the increase of fluorescence of the pH probe pyranine entrapped in the liposomal lumen during reconstitution. Proton ejection was immediately reversed by the protonophore FCCP, indicating that it is not electrically coupled to Ca(2+) uptake, but it is a primary event linked to Ca(2+) uptake in the form of countertransport. 相似文献
94.
95.
This paper presents an environmentally improved procedure for the preparative purification of a series of arginine-based gemini surfactants. The technique used was cation-exchange chromatography. Mixtures of boric-borate buffer, co-solvent (ethanol), and sodium chloride were tested as eluents. The influence of the buffer pH and the amount of co-solvent on the chromatographic process was studied for the model compound bis(Nalpha-lauroyl-L-arginine) 1,3-propanediamide dihydrochloride, C3(LA)2, and purification conditions were established. The method was scaled-up to the multigram level for C3(LA)2 and the rest of the series. The proposed preparative procedure involves simple equipment, low cost materials, and minimal amounts of solvent (water/ethanol), with low toxicity. 相似文献
96.
The action of bovine lactoferrin saturated with iron, zinc and manganese on the intracellular multiplication of Legionella pneumophila in HeLa cells has been tested. The results obtained showed that lactoferrin did not influence the invasive efficiency of Legionella. The intracellular multiplication of the bacterium was inhibited by apo-lactoferrin and by lactoferrin saturated with manganese and zinc, whereas lactoferrin saturated with iron enhanced the intracellular growth. Experiments in parallel were performed with iron, manganese and zinc citrate to test the effect due to the metal ions alone. Even in this condition the addition of an iron chelate enhanced the multiplication of Legionella while the manganese chelate produced a certain inhibition. 相似文献
97.
98.
P. Lado 《Plant biosystems》2013,147(2-3):359-369
Abstract inactivation of mitochondria in the castor bean seed endosperm during ripening. — The present research deals with the behaviour of mitochondria from the endosperm of castor bean seeds, during the last phases of seed maturation. The activities of citochrome oxidase, of malate dehydrogenase, of the succinate-citochrome c reductase system, and the phosphorylating activity, were chosen as tests of the state of mitochondria. The results obtained show an increase of the first two activities up to the moment when some ovular tissues are still present, and, successively, a more or less rapid inactivation of the three enzymes investigated, which fall to extremely low values in the dry seed. Also the phosphorylating capacity, high during the first phases, drops quickly as the seed approches to dormancy. A certain amount of citochrome oxidase is revealed in the supernatant from 20000xg centrifugation made to prepare the mitochondrial fraction; its activity gradually increases as the seed advances to ripeness. A further fractionation of the activity not sedimenting at 20000xg reveals that approximately one half of it sediments when centrifugated for 1 hour at 50000xg, while the other half remains in the supernatant. The particles sedimenting between 20000 and 50000xg show very little, if any, phosphorylating capacity (with succinate). It is suggested that the gradual inactivation of mitochondrial efficiency during the ripening phase is due to a degradation of mithochondrial structures. 相似文献
99.
Madaro L Marrocco V Fiore P Aulino P Smeriglio P Adamo S Molinaro M Bouché M 《Molecular biology of the cell》2011,22(8):1409-1419
Fusion of mononucleated myoblasts to form multinucleated myofibers is an essential phase of skeletal myogenesis, which occurs during muscle development as well as during postnatal life for muscle growth, turnover, and regeneration. Many cell adhesion proteins, including integrins, have been shown to be important for myoblast fusion in vertebrates, and recently focal adhesion kinase (FAK), has been proposed as a key mediator of myoblast fusion. Here we focused on the possible role of PKC, the PKC isoform predominantly expressed in skeletal muscle, in myoblast fusion. We found that the expression of PKC is strongly up-regulated following freeze injury-induced muscle regeneration, as well as during in vitro differentiation of satellite cells (SCs; the muscle stem cells). Using both PKC knockout and muscle-specific PKC dominant-negative mutant mouse models, we observed delayed body and muscle fiber growth during the first weeks of postnatal life, when compared with wild-type (WT) mice. We also found that myofiber formation, during muscle regeneration after freeze injury, was markedly impaired in PKC mutant mice, as compared with WT. This phenotype was associated with reduced expression of the myogenic differentiation program executor, myogenin, but not with that of the SC marker Pax7. Indeed in vitro differentiation of primary muscle-derived SCs from PKC mutants resulted in the formation of thinner myotubes with reduced numbers of myonuclei and reduced fusion rate, when compared with WT cells. These effects were associated to reduced expression of the profusion genes caveolin-3 and β1D integrin and to reduced activation/phosphorylation of their up-stream regulator FAK. Indeed the exogenous expression of a constitutively active mutant form of PKC in muscle cells induced FAK phosphorylation. Moreover pharmacologically mediated full inhibition of FAK activity led to similar fusion defects in both WT and PKC-null myoblasts. We thus propose that PKC signaling regulates myoblast fusion by regulating, at least in part, FAK activity, essential for profusion gene expression. 相似文献
100.