Research collaboration

AbstractThe complexity and cost of cardiovascular medical care dictate research to deliver high quality and cost-conscious cardiovascular care. This goal is aided by modeling medical decision making. To be useful, the modeling must be based on real data so that the results can serve as a guide to actual practice. It is suggested that a registry of randomized clinical trials and larger data bases in cardiovascular disease and health care delivery be established. The registry would be a resource for those desiring to model decision making. The registry would contain key words allowing retrieval by modelers accessing the registry and would contain contact information for consideration of possible collaborative work. The initiation of such a registry should contain plans for its evaluation to determine whether the registry itself is a cost-effective tool to encourage the needed research

Status and origin of Egyptian local rabbits in comparison with Spanish common rabbits using mitochondrial DNA sequence analysis

[EN] Mitochondrial DNA (mtDNA) and cytochrome b (cyt b) gene sequences were used to determine the status of genetic diversity and phylogeny for 132 individuals from local rabbit breeds in Egypt and Spain. The Egyptian local rabbit breeds were Egyptian Red Baladi (ERB), Egyptian Black Baladi (EBB) and Egyptian Gabali Sinai (EGS). However, the Spanish local rabbit breed was Spanish common rabbit (SCR). Previous breeds were compared with European Wild Rabbit taken from Albacete, Spain (EWR). A total of 353 mutations, 290 polymorphic sites, 14 haplotypes, 0.06126 haplotype diversity and –1.900 (P<0.05) for Tajima’s D were defined in this study. Haplotype A mostly occurred in 83.3% of Egyptian rabbits and 11.7 % of EWR, while haplotype B occurred in 63.8% of Spanish rabbits and 36.2% of the EGS breed. A total of 47 domestic and wild Oryctolagus cuniculus published sequences were used to investigate the origin and relation among the rabbit breeds tested in this study. The most common haplotype (A) was combined with 44.7% of published sequences. However, haplotype B was combined with 8.5%. Haplotypes of Egyptian, SCR and EWR were scattered in cluster 1, while we found only one EGS haplotype with two haplotypes of EWR in cluster 2. Our results assumed that genetic diversity for ERB, EBB and SCR was very low. Egyptian breeds and SCR were introduced from European rabbits. We found that ERB and EBB belong to one breed.Emam, AM.; Afonso, S.; González-Redondo, P.; Mehaisen, G.; Azoz, A.; Ahmed, N.; Fernand, N. (2020). Status and origin of Egyptian local rabbits in comparison with Spanish common rabbits using mitochondrial DNA sequence analysis. World Rabbit Science. 28(2):93-102. https://doi.org/10.4995/wrs.2020.12219OJS93102282Abrantes J., Areal H., Esteves P.J. 2013. Insights into the European rabbit (Oryctolagus cuniculus) innate immune system: genetic diversity of the toll-like receptor 3(TLR3) in wild populations and domestic breeds. BMC Genet., 14: 73. https://doi.org/10.1186/1471-2156-14-73Achilli A., Olivieri A., Pellecchia M., Uboldi C., Colli L., Al-Zahery N., Accetturo M., Pala M., Kashani B.H., Perego U.A., Battaglia V., Fornarino S., Kalamati J., Houshmand M., Negrini R., Semino O., Richards M., Macaulay V., Ferretti L., Bandelt H.J., Ajmone-Marsan P., Torroni A. 2008. Mitochondrial genomes of extinct aurochs survive in domestic cattle. Curr. Biol., 18: R157-R158. https://doi.org/10.1016/j.cub.2008.01.019Alves J.M., Carneiro, M., Afonso S., Lopes S., Garreau H., Boucher S., Allian D., Queney G., Esteves P.J., Bolet J. and Ferrnand N. 2015. Levels and patterns of genetic diversity and population structure in domestic rabbits. 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Diversity assessment among native Middle Egypt rabbit populations in North Upper-Egypt province by microsatellite polymorphism

[EN] Safeguarding biodiversity is an important goal for animal production in developed countries. This study investigated genetic diversity among native Middle-Egypt rabbit (NMER) populations in North Upper-Egypt province by using microsatellite polymorphism. Nineteen microsatellite loci were used in the study and an area of 231 km was surveyed, as native rabbits covered 14 points belonging to four Northern Upper Egypt governorates (South Giza, Fayoum, Beni Suef and Minya). Standard statistical parameters of genetic variability within and between populations confirmed that the highest genetic diversity was found towards the south. Among NMER populations, the mean number of alleles per locus was lowest in South Giza (5.32), while it was highest in Minya (6.00). This study found that NMER featured a high number of private alleles ranging between 7 and 11 (mean value was 10.5). Results also showed a high genetic diversity in NMER populations and that heterozygosity ranged between 0.384 and 0.445, strongly indicating extensive genetic variation in the NMER populations. The mean values of observed and expected heterozygosity were 0.405 and 0.612, respectively. Factorial correspondence analysis and neighbour joining trees (NJ) showed 2 main NMER rabbit groups: the Northern group (South Giza and Fayoum) and the Southern group (Beni Suef and Minya). All populations showed a high percentage of assignment in this study (0.913 to 0.946). The structure analysis showed that each population existed in separate clusters. This research provides an overview of genetic diversity of NMER populations in the Northern Upper Egypt province for the first time. In conclusion, results of this study could be used to designate priorities for conservation of NMER populations.Emam, A.; Azoz, A.; Mehaisen, G.; Ferrand, N.; Ahmed, N. (2017). Diversity assessment among native Middle Egypt rabbit populations in North Upper-Egypt province by microsatellite polymorphism. World Rabbit Science. 25(1):9-16. doi:10.4995/wrs.2017.5298.SWORD916251Abdel-Mawgood A. L. 2012. DNA Based Techniques for Studying Genetic Diversity. In Caliskan M. (Eds.) Genetic Diversity in Microorganisms, 95-122, InTechRijeka, Croatia.Abel-Kafy E. M., Shabaan H. M. A., Azoz, A. A. A., El-Sayed A. F. M., Abdel-Latif A. M. 2011. Descriptions of native rabbit breeds in Middel-Egypt. In Proc.: 4th Egyptian Conference of Rabbit Science. 30th October, 2011, Giza, Egypt.Badawy A.G. 1975. Rabbit Raising, 2nd ed. Central Administration for Agricultural Culture, Ministry of Agriculture, Egypt (in Arabic).Ben Larabi M., San-Cristobal M., Chantry-Darmon C., Bolet G. 2012. Genetic diversity of rabbit populations in Tunisia using microsatellites markers. 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Criblage phytochimique et effets d’un extrait aqueux de feuilles de Ficus exasperata Vahl. 1805 (Moraceae) sur la pression artérielle et l’activité contractile du coeur chez les mammifères

L’étude des effets de l’extrait aqueux de feuilles de Ficus exasperata (FEFIX) sur la pression artérielle de lapin et sur l’activité contractile du coeur isolé de rat a été réalisée afin de vérifier l’intérêt de l’usage de cette plante dans la pharmacopée africaine pour le traitement des oedèmes et de l’hypertension artérielle. Les composés phytochimiques et les paramètres de la toxicité aiguë de FEFIX ont été déterminés. Des doses croissantes de l’extrait aqueux de FEFIX ont été administrées au lapin afin de déterminer la DE50. L’effet de FEFIX a été évalué en présence d’atropine, de bleu de méthylène et après une hypertension induite par l’adrénaline. Différentes concentrations de FEFIX ont été perfusées à un coeur isolé. Les résultats montrent que FEFIX est essentiellement composé d’alcaloïdes, des saponosides et de flavonoïdes. Les valeurs des paramètres de la toxicité aiguë (DMT, DL50 et DL100) montrent que les doses pharmacologiques utilisées sont non toxiques. FEFIX induit une hypotension qui augmente avec la dose avec une DE50 égale à 5,46 ± 2,12 mg/kg de poids corporel (p.c.). Cette hypotension est réduite en présence d’atropine et en présence de bleu de méthylène. FEFIX réduit l’hypertension induite par l’adrénaline et ne modifie pas de manière significative l’activité contractile du coeur isolé de rat. Au terme de ce travail, il ressort que l’effet hypotenseur de FEFIX résulterait de son effet cholinomimétique et de son implication dans la libération de monoxyde d’azote (NO), tandis que l’effet antihypertenseur serait dû à l’interaction de ses composés chimiques avec les récepteurs adrénergiques.Mots clés : Ficus exasperata, hypotension, antihypertenseur, composés phytochimiques

The role of catalyst precursor anions in coal gasification

The aims of the proposed project are to enrich our understanding of the roles of various aqueous soluble catalyst precursor anions on the surface electrical properties of coal and to ascertain the influence of the surface charge on the adsorption, dispersion, and activities of calcium and potassium. These goals will be achieved by impregnating a demineralized North Dakota lignite (PSOC 1482) with calcium or potassium catalyst precursors containing acetate (CH[sub 3]COO[sup [minus]]), chloride (CI[sup [minus]]), nitrate (NO[sub 3][sup [minus]]), sulfate (SO[sub 4][sup 2[minus]]), and carbonate (CO[sub 3][sup 2[minus]]) anions. In the past quarter, the effects of (CH[sub 3]COO[sup [minus]]), CI[sup [minus]], (NO[sub 3][sup [minus]]), (CO[sub 3][sup 2[minus]]) or (CO[sub 3][sup 2[minus]]) on the surface charge properties of the coal has been initiated using the calcium salts of these anions. Like the corresponding potassium compounds investigated previously, increasing anion concentrations produce less negative charge on the coal surface through the interaction of calcium ions with the surface. This was confirmed by metal adsorption and chemical analysis of the filtered coal particles. The extent of metal adsorption was strongly dependent on the catalyst precursor. For potassium, maximum metal uptake from solution was obtained using potassium carbonate, followed by potassium acetate, while the lowest metal loadings were obtained when using the chloride, nitrate or the sulfate of potassium. The adsorption data are generally in agreement with the zeta potential results and suggest electrostatic attraction between the metal cation and the anionic coal surface. Fourier transform infrared studies are in progress to elucidate the coal-catalyst interactions

The role of catalyst precursor anions in coal gasification

The aims of the proposed project are to enrich our understanding of the roles of various aqueous soluble catalyst precursor anions on the surface electrical properties of coal and to ascertain the influence of the surface charge on the adsorption, dispersion, and activities of calcium and potassium. These goals will be achieved by impregnating a lignite and its demineralized derivative with calcium or potassium catalyst precursors containing acetate (CH{sub 3}COO{minus}), chloride (Cl{minus}), nitrate (NO{sub 3}{minus}), sulfate (SO{sub 4}{sup 2{minus}}), and carbonate (CO{sub 3}{sup 2{minus}}) anions. Catalyst loading will be conducted under well-controlled conditions of solution pH and ionic strength

Surface modified coals for enhanced catalyst dispersion and liquefaction. Quarterly report, 1996

The aim of this work is to enhance catalyst loading and dispersion in coal for improved liquefaction by preadsorption of surfactants onto coal. The application of surfactants to coal beneficiation and coal-water slurry preparation is well known. However, the effects of surfactants on catalyst loading and dispersion prior to coal conversion processes have not been investigated. The current work is focused on the influence of the cationic surfactant dodecyl dimethyl ethyl ammonium bromide (DDAB) and sodium dodecyl sulfate (SDS, anionic) on the surface properties of a bituminous coal and its molybdenum and iron uptake from solution. In the previous report, it was shown that molybdenum loading onto the coal was enhanced by preadsorption of DDAB. The optimum concentration of this surfactant for effective adsorption of molybdenum at the natural pH of the coal slurry has been determined to be in the 0.1 to 0.25 M range. Preadsorption of SDS onto the coal was found to increase the uptake of iron by the coal; iron loading increased with increase in the concentration of the catalyst precursor. This observation is attributed to the increase in the negative surface charge properties of the coal with increase in the concentration of the surfactant. The results of the study show that DDAB enhances the adsorption of molybdenum whereas SDS is more effective for iron loading onto Illinois No. 6 (DECS-24) coal

The role of catalyst precursor anions in coal gasification. Final technical report, September 1991--June 1994

The utilization of coal is currently limited by several factors, including the environmental impacts of coal use and the lack of cost-effective technologies to convert coal into useful gaseous and liquid products. Several catalysts have been evaluated for coal gasification and liquefaction. The activities of the catalysts are dependent on many factors such as the method of catalyst addition to the coal and the catalyst precursor type. Since catalyst addition to coal is frequently conducted in aqueous solution, the surface chemistry of colloidal coal particles will be expected to exert an influence on catalyst uptake. However, the effects of the various coal gasification catalyst precursors on the interfacial properties of coal during catalyst loading from solution has received little attention. The aim of this study is to ascertain the influence of the metal salts (i): calcium acetate (Ca(OOCCH{sub 3}){sub 2}), calcium chloride (CaCl{sub 2}) or calcium nitrate (Ca(NO{sub 3}){sub 2}) and (ii): potassium acetate (KOOCCH{sub 3}), potassium chloride (KCl), potassium nitrate (KNO{sub 3}), potassium carbonate (K{sub 2}CO{sub 3}) and potassium sulfate (K{sub 2}SO{sub 4}) on the electrokinetic and adsorptive properties of coal and determine the relationship, if any, between coal surface electrokinetic properties, and catalyst loading and eventually its effects on the reactivities of coal chars