Joel Ramos - Academia.edu (original) (raw)

Papers by Joel Ramos

Research paper thumbnail of The use of silver coated dressings on donor site wounds: a prospective, controlled matched pair study

Burns, 2001

Acticoat, a new silver-coated dressing, produces a moist healing environment along with the susta... more Acticoat, a new silver-coated dressing, produces a moist healing environment along with the sustained release of ionic silver for improved microbial control. These properties suggest that Acticoat might be a useful donor site dressing. However, there are no human studies which assess Acticoat for this use. The purpose of this study was to compare the healing of human skin graft donor sites dressed with Acticoat, to the healing of those dressed with Allevyn, an occlusive moist-healing environment material, which is our standard donor site dressing. In burn patients who had undergone burn excision and grafting, identical side-by-side split thickness donor site wound pairs were dressed with Allevyn and Acticoat. Re-epithelialization was directly assessed daily by a single observer from post-operative day 6 onward, and by four independent observers who rated the extent of re-epithelialization by viewing standardized digital images of the wounds that had been obtained on post-operative days 6, 8, 10,and 12. Donor sites were swabbed for bacterial culture on days 3, 6, and 9. Subsequently, each study donor site scar was rated by a blinded observer using the Vancouver Scar Scale at 1, 2, and 3 months. Sixteen paired sites in 15 patients (3 female, 12 male) were studied. Donor sites dressed with Allevyn were >90% re-epithelialized at a mean of 9.1±1.6 days while donor sites dressed with Acticoat required a mean of 14.5±6.7 days to achieve >90% re-epithelialization (P=0.004). The Allevyn sites had significantly greater estimated re-epithelialization at days 6, 8, 10 and 12 than the Acticoat sites based on the observations of the digital images. There were no significant differences in the incidence of positive bacterial cultures with either dressing at days 3, 6, and 9. Donor sites dressed with Acticoat had significantly worse scars at 1 and 2 months but this difference resolved by 3 months. Our findings do not support the use of Acticoat as a skin graft donor site dressing.

Research paper thumbnail of Hacia una estrategia de garantía de calidad: satisfacción en la utilización de los servicios médicos

Cadernos De Saude Publica, 1996

... Sierra Mojada 950, Colonia Independencia, CP 44340, Guadalajara, Jalisco, México. ArmandoMart... more ... Sierra Mojada 950, Colonia Independencia, CP 44340, Guadalajara, Jalisco, México. ArmandoMartínez Ramírez 1 Miguel Ángel Van-Dick Puga 1 Francisco Nápoles Rodríguez 1 Joel Robles Uribe 1 Alfredo Ramos Ramos 1 Ignacio Villaseñor Urrea 1 ...

Research paper thumbnail of Estabilidad de las evaluaciones genéticas en poblaciones mexicanas de bovinos para carne Stability of genetic evaluations of beef cattle Mexican populations

El propósito del estudio fue evaluar la estabilidad en los resultados de las evaluaciones genétic... more El propósito del estudio fue evaluar la estabilidad en los resultados de las evaluaciones genéticas para características de crecimiento en poblaciones mexicanas de bovinos Tropicarne y Suizo Europeo. La información analizada provino de las evaluaciones genéticas realizadas para el ganado Tropicarne en 2002 y 2003, y para Suizo Europeo en 2003 y 2004. La estabilidad de las evaluaciones se estudió considerando los animales presentes en evaluaciones consecutivas, se utilizaron los criterios: cambios en diferencias esperadas en la progenie (DEP) y exactitudes de ambas evaluaciones; correlación entre predicciones subsecuentes de DEP, porcentaje de coincidencia de animales en el grupo seleccionado, regresión de las DEP recientes sobre las anteriores, regresión de las diferencias en tendencias genéticas de evaluaciones genéticas consecutivas sobre ańo de nacimiento, y frecuencia de animales en la evaluación anterior dentro del rango (68 %) esperado de DEP en la evaluación reciente. Se detectaron cambios en la jerarquización de animales en evaluaciones consecutivas, e inestabilidad de las evaluaciones en algunas de las variables consideradas; sin embargo, prácticamente el total de los animales tuvieron cambios en las DEP de acuerdo con lo esperado, para todas las variables en las razas estudiadas (0.9613 a 0.9997). Considerando el incremento de información y por lo tanto, los diferentes modelos y parámetros genéticos utilizados, los cambios fueron los esperados y son razonables. Se recomienda verificar rutinariamente la estabilidad en las evaluaciones genéticas futuras.

Research paper thumbnail of Influência do Suporte da Ferramenta na Estabilidade Dinâmica do Fresamento de Topo Esférico a Altas Velocidades

A produção por HSC (High-Speed-Cutting) é caracterizada por crescentes exigências sobre o comport... more A produção por HSC (High-Speed-Cutting) é caracterizada por crescentes exigências sobre o comportamento dinâmico do sistema máquina-ferramenta-peça. A vibração é um dos problemas que limitam o processo. O progresso desta tecnologia tem sido limitado pelo desgaste prematuro das ferramentas, dos rolamentos dos eixos árvores e instabilidades dinâmicas no sistema. O processo de fresamento a altas velocidades de corte é caracterizado pela otimização da taxa de remoção de material, elevada precisão dimensional, redução das forças de corte, usinagem dentro de tolerâncias mais estreitas e acabamento superficial adequado, mas só pode utilizar toda a sua potencialidade se a usinagem for mantida em regiões isentas de vibração. A usinagem de materiais é invariavelmente acompanhada de vibrações entre a ferramenta e a peça. As vibrações podem ter origem em uma ou mais fontes: vibração externa à máquina-ferramenta, vibrações geradas pela própria usinagem, falta de homogeneidade da peça, corte interrompido e vibrações causadas pela máquina-ferramenta. O nível máximo de vibração tolerável depende da aplicação que será destinada a usinagem. Em operações de desbaste, o que determina o nível aceitável de vibração é principalmente o efeito da vibração sobre a vida da ferramenta. Em operações de acabamento os parâmetros analisados são qualidade superficial e precisão dimensional. Um processo estável pode ser caracterizado por boa qualidade superficial, enquanto um instável é associado a um acabamento superficial deteriorado.

Research paper thumbnail of An RNase P RNA subunit mutation affects ribosomal RNA processing

Nucleic Acids Research, 1996

RNase P is a ribonucleoprotein endoribonuclease responsible for the 5′ maturation of precursor tR... more RNase P is a ribonucleoprotein endoribonuclease responsible for the 5′ maturation of precursor tRNAs in all organisms. While analyzing mutations in conserved positions of the yeast nuclear RNase P RNA subunit, significant accumulation of an aberrant RNA of ∼193 nucleotides was observed. This abundant RNA was identified as a 3′ extended form of the 5.8S rRNA. This strain also displays a slightly elevated level of other rRNA processing intermediates with 5′-ends at processing site A2 in the internal transcribed spacer 1 (ITS1) region of the rRNA primary transcript. To test whether pre-rRNA in the region of ITS1/5.8S/ITS2 is a substrate for RNase P in vitro, nuclear RNase P was partially purified to remove contaminating nucleases. Cleavage assays were performed using an rRNA substrate transcribed in vitro which includes the 5.8S region and its surrounding processing sites in ITS1 and ITS2. Discrete cleavages of this rRNA substrate were coincident with the peak fractions of nuclear RNase P, but not with fractions corresponding to mitochondrial RNase P or ribonuclease MRP RNA. The cleavage activity is sensitive to treatment with micrococcal nuclease, also consistent with an activity attributable to RNase P. The strong RNase P cleavage sites were mapped and their possible relationships to steps in the rRNA processing pathway are considered. These observations suggest an intimate relationship between the processes of tRNA and rRNA maturation in the eukaryotic nucleus.

Research paper thumbnail of The use of silver coated dressings on donor site wounds: a prospective, controlled matched pair study

Burns, 2001

Acticoat, a new silver-coated dressing, produces a moist healing environment along with the susta... more Acticoat, a new silver-coated dressing, produces a moist healing environment along with the sustained release of ionic silver for improved microbial control. These properties suggest that Acticoat might be a useful donor site dressing. However, there are no human studies which assess Acticoat for this use. The purpose of this study was to compare the healing of human skin graft donor sites dressed with Acticoat, to the healing of those dressed with Allevyn, an occlusive moist-healing environment material, which is our standard donor site dressing. In burn patients who had undergone burn excision and grafting, identical side-by-side split thickness donor site wound pairs were dressed with Allevyn and Acticoat. Re-epithelialization was directly assessed daily by a single observer from post-operative day 6 onward, and by four independent observers who rated the extent of re-epithelialization by viewing standardized digital images of the wounds that had been obtained on post-operative days 6, 8, 10,and 12. Donor sites were swabbed for bacterial culture on days 3, 6, and 9. Subsequently, each study donor site scar was rated by a blinded observer using the Vancouver Scar Scale at 1, 2, and 3 months. Sixteen paired sites in 15 patients (3 female, 12 male) were studied. Donor sites dressed with Allevyn were >90% re-epithelialized at a mean of 9.1±1.6 days while donor sites dressed with Acticoat required a mean of 14.5±6.7 days to achieve >90% re-epithelialization (P=0.004). The Allevyn sites had significantly greater estimated re-epithelialization at days 6, 8, 10 and 12 than the Acticoat sites based on the observations of the digital images. There were no significant differences in the incidence of positive bacterial cultures with either dressing at days 3, 6, and 9. Donor sites dressed with Acticoat had significantly worse scars at 1 and 2 months but this difference resolved by 3 months. Our findings do not support the use of Acticoat as a skin graft donor site dressing.

Research paper thumbnail of Hacia una estrategia de garantía de calidad: satisfacción en la utilización de los servicios médicos

Cadernos De Saude Publica, 1996

... Sierra Mojada 950, Colonia Independencia, CP 44340, Guadalajara, Jalisco, México. ArmandoMart... more ... Sierra Mojada 950, Colonia Independencia, CP 44340, Guadalajara, Jalisco, México. ArmandoMartínez Ramírez 1 Miguel Ángel Van-Dick Puga 1 Francisco Nápoles Rodríguez 1 Joel Robles Uribe 1 Alfredo Ramos Ramos 1 Ignacio Villaseñor Urrea 1 ...

Research paper thumbnail of Estabilidad de las evaluaciones genéticas en poblaciones mexicanas de bovinos para carne Stability of genetic evaluations of beef cattle Mexican populations

El propósito del estudio fue evaluar la estabilidad en los resultados de las evaluaciones genétic... more El propósito del estudio fue evaluar la estabilidad en los resultados de las evaluaciones genéticas para características de crecimiento en poblaciones mexicanas de bovinos Tropicarne y Suizo Europeo. La información analizada provino de las evaluaciones genéticas realizadas para el ganado Tropicarne en 2002 y 2003, y para Suizo Europeo en 2003 y 2004. La estabilidad de las evaluaciones se estudió considerando los animales presentes en evaluaciones consecutivas, se utilizaron los criterios: cambios en diferencias esperadas en la progenie (DEP) y exactitudes de ambas evaluaciones; correlación entre predicciones subsecuentes de DEP, porcentaje de coincidencia de animales en el grupo seleccionado, regresión de las DEP recientes sobre las anteriores, regresión de las diferencias en tendencias genéticas de evaluaciones genéticas consecutivas sobre ańo de nacimiento, y frecuencia de animales en la evaluación anterior dentro del rango (68 %) esperado de DEP en la evaluación reciente. Se detectaron cambios en la jerarquización de animales en evaluaciones consecutivas, e inestabilidad de las evaluaciones en algunas de las variables consideradas; sin embargo, prácticamente el total de los animales tuvieron cambios en las DEP de acuerdo con lo esperado, para todas las variables en las razas estudiadas (0.9613 a 0.9997). Considerando el incremento de información y por lo tanto, los diferentes modelos y parámetros genéticos utilizados, los cambios fueron los esperados y son razonables. Se recomienda verificar rutinariamente la estabilidad en las evaluaciones genéticas futuras.

Research paper thumbnail of Influência do Suporte da Ferramenta na Estabilidade Dinâmica do Fresamento de Topo Esférico a Altas Velocidades

A produção por HSC (High-Speed-Cutting) é caracterizada por crescentes exigências sobre o comport... more A produção por HSC (High-Speed-Cutting) é caracterizada por crescentes exigências sobre o comportamento dinâmico do sistema máquina-ferramenta-peça. A vibração é um dos problemas que limitam o processo. O progresso desta tecnologia tem sido limitado pelo desgaste prematuro das ferramentas, dos rolamentos dos eixos árvores e instabilidades dinâmicas no sistema. O processo de fresamento a altas velocidades de corte é caracterizado pela otimização da taxa de remoção de material, elevada precisão dimensional, redução das forças de corte, usinagem dentro de tolerâncias mais estreitas e acabamento superficial adequado, mas só pode utilizar toda a sua potencialidade se a usinagem for mantida em regiões isentas de vibração. A usinagem de materiais é invariavelmente acompanhada de vibrações entre a ferramenta e a peça. As vibrações podem ter origem em uma ou mais fontes: vibração externa à máquina-ferramenta, vibrações geradas pela própria usinagem, falta de homogeneidade da peça, corte interrompido e vibrações causadas pela máquina-ferramenta. O nível máximo de vibração tolerável depende da aplicação que será destinada a usinagem. Em operações de desbaste, o que determina o nível aceitável de vibração é principalmente o efeito da vibração sobre a vida da ferramenta. Em operações de acabamento os parâmetros analisados são qualidade superficial e precisão dimensional. Um processo estável pode ser caracterizado por boa qualidade superficial, enquanto um instável é associado a um acabamento superficial deteriorado.

Research paper thumbnail of An RNase P RNA subunit mutation affects ribosomal RNA processing

Nucleic Acids Research, 1996

RNase P is a ribonucleoprotein endoribonuclease responsible for the 5′ maturation of precursor tR... more RNase P is a ribonucleoprotein endoribonuclease responsible for the 5′ maturation of precursor tRNAs in all organisms. While analyzing mutations in conserved positions of the yeast nuclear RNase P RNA subunit, significant accumulation of an aberrant RNA of ∼193 nucleotides was observed. This abundant RNA was identified as a 3′ extended form of the 5.8S rRNA. This strain also displays a slightly elevated level of other rRNA processing intermediates with 5′-ends at processing site A2 in the internal transcribed spacer 1 (ITS1) region of the rRNA primary transcript. To test whether pre-rRNA in the region of ITS1/5.8S/ITS2 is a substrate for RNase P in vitro, nuclear RNase P was partially purified to remove contaminating nucleases. Cleavage assays were performed using an rRNA substrate transcribed in vitro which includes the 5.8S region and its surrounding processing sites in ITS1 and ITS2. Discrete cleavages of this rRNA substrate were coincident with the peak fractions of nuclear RNase P, but not with fractions corresponding to mitochondrial RNase P or ribonuclease MRP RNA. The cleavage activity is sensitive to treatment with micrococcal nuclease, also consistent with an activity attributable to RNase P. The strong RNase P cleavage sites were mapped and their possible relationships to steps in the rRNA processing pathway are considered. These observations suggest an intimate relationship between the processes of tRNA and rRNA maturation in the eukaryotic nucleus.