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Papers by juan ignacio vargas flores
Journal of Non Crystalline Solids, 2008
We prepared SiO 2 @Ag core-shell nanospheres: silver nanoparticles ($4 ± 2 nm in diameter) coated... more We prepared SiO 2 @Ag core-shell nanospheres: silver nanoparticles ($4 ± 2 nm in diameter) coated silica nanospheres ($50 ± 10 nm in diameter). The preparation route is a modification of the Stöber method, and involves the preparation of homogeneous silica spheres at room temperature, combined with the deposition of silver nanoparticles from Ag + in solution, by using water/ethanol mixtures, tetraethylorthosilicate as Si source and silver nitrate as Ag source in a single-pot wet chemical route without an added coupling agent or surface modification, which leads to the formation of core@shell homogeneous nanospheres. We present the preparation and characterization of the SiO 2 @Ag core-shell nanospheres and also of bare silica spheres in the absence of silver, and propose a reaction mechanism for the formation of the core-shell structure.
Journal of Organometallic Chemistry, Dec 1, 2002
The compound 4-LiC 6 H 4 N(SiMe 3 ) 2 reacted in tetrahydrofuran with SiMe 3 Cl or with silicon-c... more The compound 4-LiC 6 H 4 N(SiMe 3 ) 2 reacted in tetrahydrofuran with SiMe 3 Cl or with silicon-chloride groups located at the periphery of carbosilane dendrimers of first, second, and third generation to afford 44 ] (11), in which the metal moieties are linked to the carbosilane framework through imido Ã/ metal bonds. The structure of complexes 4 and 5 has been determined by X-ray diffraction methods. #
Journal of Clinical Microbiology, 2014
31 32 New dual tests for HIV and syphilis have been developed. Our study aimed to evaluate the 33... more 31 32 New dual tests for HIV and syphilis have been developed. Our study aimed to evaluate the 33 laboratory performance of a dual rapid immunodiagnostic test for HIV and syphilis. Our 34 evaluation showed high performance of this dual rapid test, which should be considered for 35 implementation to increase screening coverage and efficiency. 36 37 on June 13, 2016 by guest http://jcm.asm.org/ Downloaded from Lab eval_medmira_24Oct2014_R1 3 Syphilis is a curable disease, yet 10 million persons worldwide have new syphilis infections each 38 year.(1) Syphilis frequently has atypical presentations that may be difficult to differentiate 39 from other sexually transmitted infections (STIs), making effective diagnostics essential for the 40 identification of infection.(2) In 2012, over 35 million people were infected with human 41 immunodeficiency virus (HIV).(3) HIV and syphilis infection screening should be offered to 42 every pregnant women to prevent adverse outcomes of pregnancy that include still birth, 43 prematurity, neonatal death, or mother-to-child transmission of syphilis and/or HIV 44 infection.(4-6) 45 46 Syphilis infection during pregnancy is associated with over a 2.7 fold increased risk of mother-47 to-child HIV transmission.(7) Additionally, syphilis infection, like other genital ulcer diseases, 48 may facilitate HIV acquisition and transmission.(8-10) In co-infected patients, syphilis can 49 increase transmission of HIV by increasing viral shedding at the site of genital ulcers(11, 12) and 50 increases HIV viral load(13, 14). 51 52 Syphilis infection is generally diagnosed using two serologic laboratory-based tests; however, 53 over the past 10 years, the advent of syphilis rapid tests have allowed for point-of-care 54 screening.(15, 16) In order to increase screening coverage, new dual tests for HIV and syphilis 55 have been developed.(17-19) These dual tests will allow for syphilis, a disease with less 56 advocacy and donor funding, to become part of HIV prevention programs.(20) Our study 57 aimed to evaluate the laboratory performance of a dual rapid immunodiagnostic test for HIV 58 and syphilis. 59 on June 13, 2016 by guest http://jcm.asm.org/ Downloaded from Lab eval_medmira_24Oct2014_R1 4 60 61
Journal of Non Crystalline Solids, 2008
We prepared SiO 2 @Ag core-shell nanospheres: silver nanoparticles ($4 ± 2 nm in diameter) coated... more We prepared SiO 2 @Ag core-shell nanospheres: silver nanoparticles ($4 ± 2 nm in diameter) coated silica nanospheres ($50 ± 10 nm in diameter). The preparation route is a modification of the Stöber method, and involves the preparation of homogeneous silica spheres at room temperature, combined with the deposition of silver nanoparticles from Ag + in solution, by using water/ethanol mixtures, tetraethylorthosilicate as Si source and silver nitrate as Ag source in a single-pot wet chemical route without an added coupling agent or surface modification, which leads to the formation of core@shell homogeneous nanospheres. We present the preparation and characterization of the SiO 2 @Ag core-shell nanospheres and also of bare silica spheres in the absence of silver, and propose a reaction mechanism for the formation of the core-shell structure.
Journal of Organometallic Chemistry, Dec 1, 2002
The compound 4-LiC 6 H 4 N(SiMe 3 ) 2 reacted in tetrahydrofuran with SiMe 3 Cl or with silicon-c... more The compound 4-LiC 6 H 4 N(SiMe 3 ) 2 reacted in tetrahydrofuran with SiMe 3 Cl or with silicon-chloride groups located at the periphery of carbosilane dendrimers of first, second, and third generation to afford 44 ] (11), in which the metal moieties are linked to the carbosilane framework through imido Ã/ metal bonds. The structure of complexes 4 and 5 has been determined by X-ray diffraction methods. #
Journal of Clinical Microbiology, 2014
31 32 New dual tests for HIV and syphilis have been developed. Our study aimed to evaluate the 33... more 31 32 New dual tests for HIV and syphilis have been developed. Our study aimed to evaluate the 33 laboratory performance of a dual rapid immunodiagnostic test for HIV and syphilis. Our 34 evaluation showed high performance of this dual rapid test, which should be considered for 35 implementation to increase screening coverage and efficiency. 36 37 on June 13, 2016 by guest http://jcm.asm.org/ Downloaded from Lab eval_medmira_24Oct2014_R1 3 Syphilis is a curable disease, yet 10 million persons worldwide have new syphilis infections each 38 year.(1) Syphilis frequently has atypical presentations that may be difficult to differentiate 39 from other sexually transmitted infections (STIs), making effective diagnostics essential for the 40 identification of infection.(2) In 2012, over 35 million people were infected with human 41 immunodeficiency virus (HIV).(3) HIV and syphilis infection screening should be offered to 42 every pregnant women to prevent adverse outcomes of pregnancy that include still birth, 43 prematurity, neonatal death, or mother-to-child transmission of syphilis and/or HIV 44 infection.(4-6) 45 46 Syphilis infection during pregnancy is associated with over a 2.7 fold increased risk of mother-47 to-child HIV transmission.(7) Additionally, syphilis infection, like other genital ulcer diseases, 48 may facilitate HIV acquisition and transmission.(8-10) In co-infected patients, syphilis can 49 increase transmission of HIV by increasing viral shedding at the site of genital ulcers(11, 12) and 50 increases HIV viral load(13, 14). 51 52 Syphilis infection is generally diagnosed using two serologic laboratory-based tests; however, 53 over the past 10 years, the advent of syphilis rapid tests have allowed for point-of-care 54 screening.(15, 16) In order to increase screening coverage, new dual tests for HIV and syphilis 55 have been developed.(17-19) These dual tests will allow for syphilis, a disease with less 56 advocacy and donor funding, to become part of HIV prevention programs.(20) Our study 57 aimed to evaluate the laboratory performance of a dual rapid immunodiagnostic test for HIV 58 and syphilis. 59 on June 13, 2016 by guest http://jcm.asm.org/ Downloaded from Lab eval_medmira_24Oct2014_R1 4 60 61