984 resultados para 2 `-deoxyadenosine-5 `-monophosphate
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myo-Inositol phosphates possessing the 1,2,3-trisphosphate motif share the remarkable ability to completely inhibit iron-catalysed hydroxyl radical formation. The simplest derivative, myo-inositol 1,2,3-trisphosphate [Ins(1,2,3)P3], has been proposed as an intracellular iron chelator involved in iron transport. The binding conformation of Ins(1,2,3)P3 is considered to be important to complex Fe3+ in a 'safe' manner. Here, a pyrene-based fluorescent probe, 4,6-bispyrenoyl-myo-inositol 1,2,3,5-tetrakisphosphate [4,6-bispyrenoyl Ins(1,2,3,5)P4], has been synthesised and used to monitor the conformation of the 1,2,3-trisphosphate motif using excimer fluorescence emission. Ring-flip of the cyclohexane chair to the penta-axial conformation occurs upon association with Fe3+, evident from excimer fluorescence induced by π-π stacking of the pyrene reporter groups, accompanied by excimer formation by excitation at 351 nm. This effect is unique amongst biologically relevant metal cations, except for Ca 2+ cations exceeding a 1:1 molar ratio. In addition, the thermodynamic constants for the interaction of the fluorescent probe with Fe3+ have been determined. The complexes formed between Fe 3+ and 4,6-bispyrenoyl Ins(1,2,3,5)P4 display similar stability to those formed with Ins(1,2,3)P3, indicating that the fluorescent probe acts as a good model for the 1,2,3-trisphosphate motif. This is further supported by the antioxidant properties of 4,6-bispyrenoyl Ins(1,2,3,5)P4, which closely resemble those obtained for Ins(1,2,3)P3. The data presented confirms that Fe3+ binds tightly to the unstable penta-axial conformation of myo-inositol phosphates possessing the 1,2,3-trisphosphate motif. © 2010 The Royal Society of Chemistry.
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The antiviral or anticancer activities of C-5 modified pyrimidine nucleoside analogues validate the need for the development of their syntheses. In the first half of this dissertation, I explore the Pd-catalyzed cross-coupling reaction of allylphenylgermanes with aryl halides in the presence of SbF 5/TBAF to give various biaryls by transferring multiple phenyl groups, which has also been applied to the 5-halo pyrimidine nucleosides for the synthesis of 5-aryl derivatives. To avoid the use of organometallic reagents, I developed Pd-catalyzed direct arylation of 5-halo pyrimidine nucleosides. It was discovered that 5-aryl pyrimidine nucleosides could be synthesized by Pd-catalyzed direct arylation of N3-free 5-halo uracil and uracil nucleosides with simple arenes or heteroaromatics in the presence of TBAF within 1 h. Both N3-protected and N3-free uracil and uracil nucleosides could undergo base-promoted Pd-catalyzed direct arylation, but only with electron rich heteroaromatics. ^ In the second half of this dissertation, 5-acetylenic uracil and uracil nucleosides have been employed to investigate the hydrogermylation, hydrosulfonylation as well as hydroazidation for the synthesis of various functionalized 5-vinyl pyrimidine nucleosides. Hydrogermylation of 5-alkynyl uracil analogues with trialkylgermane or tris(trimethylsilyl)germane hydride gave the corresponding vinyl trialkylgermane, or tris(trimethylsilyl)germane uracil derivatives. During the hydrogermylation with triphenylgermane, besides the vinyl triphenylgermane uracil derivatives, 5-[2-(triphenylgermyl)acetyl]uracil was also isolated and characterized and the origin of the acetyl oxygen was clarified. Tris(trimethylsilyl)germane uracil derivatives were coupled to aryl halides but with decent yield. Iron-mediated regio- and stereoselective hydrosulfonylation of the 5-ethynyl pyrimidine analogues with sulfonyl chloride or sulfonyl hydrazine to give 5-(1-halo-2-tosyl)vinyluracil nucleoside derivatives has been developed. Nucleophilic substitution of the 5-(β-halovinyl)sulfonyl nucleosides with various nucleophiles have been performed to give highly functionalized 5-vinyl pyrimidine nucleosides via the addition-elimination mechanism. The 5-(β-keto)sulfonyluracil derivative has also been synthesized via the aerobic difunctionalization of 5-ethynyluracil analogue with sulfinic acid in the presence of catalytic amount of pyridine. Silver catalyzed hydroazidation of protected 2'-deoxy-5-ethynyluridine with TMSN3 in the presence of catalytic amount of water to give 5-(α-azidovinyl)uracil nucleoside derivatives was developed. Strain promoted Click reaction of the 5-(α-azidovinyl)uracil with cyclooctyne provide the corresponding fully conjugated triazole product.^
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Concentrations of tin in sea water decreased from estuarine and shelf (0.02-0.04 µg/kg) to surface Atlantic waters (0.009 µg/kg). Mean contents (ppm) in other materials included: ultramafic rocks, 0.8; basalts, 1.7; silicic rocks, 2.5; red clays, 3.4; amphibolites, 1.2. Oceanic ferromanganese deposits contained from 0.2 to 5.8 ppm; tin and cobalt contents were correlated.
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Dengue is a viral disease transmitted by female mosquitoes from genus Aedes, the principal urban vector is Aedes aegypti. Actually dengue has caused, in global scale, substantial morbidity and mortality. Four serotypes (antigenically distinct) are known: DENV-1, DENV-2, DENV-3 and DENV-4. The objective of this study was described the epidemiological profile dengue in the states of Rio Grande do Norte (RN) and Paraíba (PB), 2013. For that, suspected cases of dengue were studied, received for Laboratory of Molecular Biology of infectious disease and cancer (LADIC-UFRN) from different Health Units from RN and PB between January and December of 2013. The viral RNA was obtained from serum samples of patient from health units from RN and PB. It were studied 478 suspected cases of dengue , 252 (52,7%) from Rio Grande do Norte and 226 (47,3%) from Paraíba, showeds a global rate of infection global prevalence of 29,7% (142/478). The co-circulation of three serotypes was observed: DENV-1 (9,8% [14/142]), DENV-2 (3,5% [5/142]) and DENV-4 (86,7% [123/142]). People between 21-30 years old were the most affected by the disease during all the period of the study, representing 63,7% of the cases in both states. The genus most affected was female, representing 63,3% of cases in both states. Pau dos Ferros, Rio Grande do Norte, had the highest circulation of disease, with 8,2% (8/97) of cases. In Paraíba, the city most affected was João Pessoa, with (80% (36/45) of cases. The months with the biggest viral circulation in RN and PB were March and August, respectively. These results are very important to understanding the dengue viral activity in RN and PB, providing data that can guide control actions of this disease in support to local control programs
Resumo:
The antiviral or anticancer activities of C-5 modified pyrimidine nucleoside analogues validate the need for the development of their syntheses. In the first half of this dissertation, I explore the Pd-catalyzed cross-coupling reaction of allylphenylgermanes with aryl halides in the presence of SbF5/TBAF to give various biaryls by transferring multiple phenyl groups, which has also been applied to the 5-halo pyrimidine nucleosides for the synthesis of 5-aryl derivatives. To avoid the use of organometallic reagents, I developed Pd-catalyzed direct arylation of 5-halo pyrimidine nucleosides. It was discovered that 5-aryl pyrimidine nucleosides could be synthesized by Pd-catalyzed direct arylation of N3-free 5-halo uracil and uracil nucleosides with simple arenes or heteroaromatics in the presence of TBAF within 1 h. Both N3-protected and N3-free uracil and uracil nucleosides could undergo base-promoted Pd-catalyzed direct arylation, but only with electron rich heteroaromatics. In the second half of this dissertation, 5-acetylenic uracil and uracil nucleosides have been employed to investigate the hydrogermylation, hydrosulfonylation as well as hydroazidation for the synthesis of various functionalized 5-vinyl pyrimidine nucleosides. Hydrogermylation of 5-alkynyl uracil analogues with trialkylgermane or tris(trimethylsilyl)germane hydride gave the corresponding vinyl trialkylgermane, or tris(trimethylsilyl)germane uracil derivatives. During the hydrogermylation with triphenylgermane, besides the vinyl triphenylgermane uracil derivatives, 5-[2-(triphenylgermyl)acetyl]uracil was also isolated and characterized and the origin of the acetyl oxygen was clarified. Tris(trimethylsilyl)germane uracil derivatives were coupled to aryl halides but with decent yield. Iron-mediated regio- and stereoselective hydrosulfonylation of the 5-ethynyl pyrimidine analogues with sulfonyl chloride or sulfonyl hydrazine to give 5-(1-halo-2-tosyl)vinyluracil nucleoside derivatives has been developed. Nucleophilic substitution of the 5-(β-halovinyl)sulfonyl nucleosides with various nucleophiles have been performed to give highly functionalized 5-vinyl pyrimidine nucleosides via the addition-elimination mechanism. The 5-(β-keto)sulfonyluracil derivative has also been synthesized via the aerobic difunctionalization of 5-ethynyluracil analogue with sulfinic acid in the presence of catalytic amount of pyridine. Silver catalyzed hydroazidation of protected 2'-deoxy-5-ethynyluridine with TMSN3 in the presence of catalytic amount of water to give 5-(α-azidovinyl)uracil nucleoside derivatives was developed. Strain promoted Click reaction of the 5-(α-azidovinyl)uracil with cyclooctyne provide the corresponding fully conjugated triazole product.
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The cores and dredges described in this report were taken on the KH-71-5, Phoenix Expedition in Nov 1971 until March 1972 by the Ocean Research Institute, University of Tokyo from the R/V Hakuho Maru. A total of 13 cores and dredges sites have been recovered.
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Las infecciones de vías urinarias es un problema frecuente en la edad pediátrica, con una prevalencia de 2 al 5%. El diagnóstico de certeza es importante para la administración del tratamiento adecuado, el cual debe de ser eficaz para evitar un alto riesgo de desarrollo de cicatrices renales en niños con pielonefritis, con posibilidad en el adulto de hipertensión arterial e insuficiencia renal crónica. El tratamiento etiológico precisa el empleo de antibióticos, inicialmente de forma empírica atendiendo la etiología más probable, el patrón de sensibilidad y resistencias antimicrobianas, con posibles variaciones locales. Objetivo: identificar el patrón de sensibilidad y resistencia antimicrobiana de las bacterias aisladas en los pacientes de 1 mes a 5 años de edad, con infección de vías urinarias atendidos en la unidad de emergencia del Hospital Nacional de Niños Benjamín Bloom, durante el período de Enero a Diciembre 2012. Metodología: se realizó un estudio descriptivo, de corte retrospectivo, con una población que incluyó los niños de 1 mes a 5 años, con diagnóstico de infección de vías urinarias, atendidos en la unidad de emergencia del Hospital Nacional de Niños Benjamín Bloom, durante el periodo comprendido de Enero a Diciembre 2012. Los datos fueron recolectados a partir de la revisión de expedientes clínicos. Se realizó el análisis de información y determinación de resultados por medio del programa Excel. Dicho trabajo fue sometido a una evaluación por el Comité de Ética en Investigación clínica, siendo aprobado y autorizando su realización. Resultados: el agente etiológico más frecuente fue E. coli, con un patrón de sensibilidad y resistencia antimicrobiano definido con una sensibilidad a amikacina, meropenem, ceftriaxona, nitrofurantoina y cefepime, y una resistencia a ampicilina, TMP SMX y la gentamicina. El tratamiento empírico recomendado en base al agente etiológico más frecuente aislado y su patrón de sensibilidad y resistencia antimicrobiano, es la CEFTRIAXONA.
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ANTECEDENTES: El trauma encéfalo craneal (TEC), es una de las principales causas de atención en emergencia pediátrica del país y el mundo. Representa una carga en morbilidad y mortalidad, constituyendo una causa importante de internamiento, complicaciones y muerte en pediatría. OBJETIVOS: Determinar la prevalencia de TEC y factores asociados en niños de 0 a 5 años atendidos en emergencia del Hospital Vicente Corral Moscoso, Febrero- Julio 2014. MÉTODO Y TÉCNICAS Se realizó un estudio transversal en niños de 0 a 5 años con TEC, atendidos en emergencia del HVCM, de febrero a julio del 2014, determinando la prevalencia y factores asociados a TEC; previa firma de consentimiento informado por los representantes. Tras recolectarse los datos, estos fueron codificados y tabulados mediante SPSS versión 20, obteniendo las variables demográficas de estudio. RESULTADOS Se estudiaron 1681 niños, con un promedio en edad de 26,2 meses (DS 20,76). La prevalencia de TEC fue del 10,4%. El TEC leve representó el 8,6% del total de niños. Los factores positivos asociados fueron: estar a cuidado de terceros o sin cuidador (RP: 3,91; IC: 2,94-5,20); pertenecer a un grupo minoritario, indígena o negro (RP: 3,64; IC: 2,46-5,39); siendo el maltrato infantil la variable que más se relacionó con TEC. (RP: 6,11; IC: 3,61-10,65). CONCLUSIONES: La prevalencia de TEC en el HVCM en niños de 0 a 5 años, fue de 10,4%. Asociándose positivamente con etnia indígena o negra, encontrarse sin cuidador o a cargo de terceros y el maltrato infantil.
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El objetivo de esta investigación fue evaluar el efecto de zeolita (Clinoptilolita) adicionado en la dieta basal de vacas lecheras durante 105 días, 60 días pre-parto (dap) y 45 días post-parto (dpp) y su influencia en la involución (IU) y salud uterina (SU), el retorno de la actividad ovárica (AO) y la condición corporal (CC). El proyecto se realizó en tres ganaderías de la comunidad de Soldados del Cantón Cuenca – Azuay, en 50 vacas secas, con una CC ≥ 3,5, entre 2 a 5 partos, clínicamente sanas y todas en las mismas condiciones sanitarias y de manejo; fueron divididas en un grupo control (n1=25), alimentadas con dieta basal y un experimental (n2=25), con dieta basal + 2% de Zeolita del consumo de materia (CMS). Se evaluó retorno de AO considerando folículos ≥ 10 mm de diámetro a los 15, 22, 35 y 45 dpp por Ultrasonografía transrectal, SU (>10 PMN) a los 35 dpp por cytobrush, IU considerando posición del útero con respecto a la pelvis (PU), simetría de los cuernos (SCU), y diámetro del cérvix (DC), a los 22 y 45 dpp por palpación rectal, y finalmente la CC a los 15 dap, parto y 45 dpp. Se usó un diseño completamente al azar (DCA) y los resultados fueron analizados con el programa estadístico SPSS versión 22.0, posteriormente fueron aplicados los estadísticos de “U de Mann Withney y Kruscall Wallis”. Se obtuvo eficacia en el GE con mayor porcentaje de vacas que retornaron su AO (respectivamente, para GC y GE fueron: 35 dpp 29,6% vs. 70,4%; 45 dpp 44,4% vs. 55,6%; p<0,05). La IU fue a los 45 dpp, los valores obtenido para GC y GE fueron: respectivamente, PU 40,0% vs. 76,0%, SCU 32,0% vs. 76,0% y DC 28,0% vs. 68,0%, (p<0,05). Y en SU también mostró eficacia en el GE obteniendo un 3,4% vs. 22,2% de PMN en comparación con el GC, (p<0,05). Finalmente, se comprobó diferencias significativas (p<0,05) en la CC al parto y 45 dpp con eficacia atribuida al GE. En conclusión, la adición de zeolita al 2% en la dieta basal mostró eficacia en la involución y salud uterina, retorno de la actividad ovárica y la condición corporal en vacas en transición, recomendando su uso en las ganaderías lecheras
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We have described that Galanin N-terminal fragment (1-15) [GAL(1-15)] is associated with depressive effects and also modulates the antidepressant effects induced by the 5-HT1A receptor (5-HT1AR) agonist 8-OH-DPAT. The aim of this study is to analyze the ability of GAL(1-15) to modulate 5-HT1AR at the autoreceptor and postsynaptic receptor level in rats by using quantitative autoradiography. We analyzed the effect of intracerebroventricular GAL(1-15)-3nmol (n=6) or aCSF (n=6), 10 minutes, 2 and 5 hours after the injection, on the binding characteristics of the 5-HT1AR agonist [H3]-8-OH-DPAT in sections of the Dorsal Raphe (DR) and Dorsal Hippocampus, specifically CA1 and Dentate Gyrus (DG). Student’s t-test was used to compare the experimental groups. GAL(1-15) produced a time-dependent effect on the binding of [H3]-8-OH-DPAT. In CA1 and DG, a significant increase in the KD and Bmax was observed, by 90%(p<0.05), at 10 minutes and 2 hours after injection. However, 5 hours after GAL(1-15) the only significant change remaining was the increase in Bmax at the DG. The coinjection of the GALR2 antagonist M871 blocked significantly the effects induced by GAL(1-15) in both areas. In DR, 2 hours after injection GAL(1-15) only produced a decrease in the Bmax by 20%(p<0.05). These results indicate that GAL(1-15) interacts with 5-HT1AR at the receptor level in DR and Dorsal Hippocampus. Therapeutic strategies based on these results could be developed for the treatment of depression disorders. This work has been supported by Junta de Andalucia CVI646 and Spanish Ministry of Economy PSI2013-44901-P.
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Introducción: Siendo la desnutrición infantil, un indicador trazador en el perfil de salud de una población y prioridad establecida por los objetivos de desarrollo del milenio y el plan decenal de salud pública en Colombia - PDSP en su dimensión de seguridad alimentaria y nutricional, mantiene gran prevalencia a nivel nacional a pesar de presentar subregistro en la información reportada, por ende, es prioridad la medición, notificación y tratamiento de la misma. La OMS estandarizó los parámetros de medición y el gobierno nacional los adoptó mediante la resolución 2121 de 2010. Sin embargo, para disminuir el indicador de desnutrición que al año 2015 debería estar reducido en un 50% según el PDSP, es necesario identificar el sub registro que hay en el diagnóstico de la misma. Metodología: Se realizó un estudio poblacional, descriptivo y transversal, en el cual se analizó la base de datos de los niños menores de 5 años asistentes a consulta de crecimiento y desarrollo en una institución de salud del municipio de Puerto Inírida, con el fin de realizar una caracterización nutricional basados en mediciones antropométricas y contrastándolas realizadas por los profesionales de salud con las encontradas utilizando los patrones establecidos por la OMS. La información se analizó con el Software WHO Anthro propiedad de la OMS. Resultados: Se encontró que el 33,6% de los menores de 5 años registrados presentan desnutrición crónica, el 7,6% desnutrición aguda, el 13,2% de desnutrición global y el 13,9% tiene obesidad. Al discriminarlo por edad se encontró mayor prevalencia de desnutrición crónica en ambos sexos, siendo mayor en población de sexo masculino (40,1% masculino – 27,6% femenino); al igual que al realizar la comparación por pertenencia puesto que se encuentra la misma prevalencia en desnutrición crónica (29,1% en población indígena y 29% en población no indígena). Según los estándares de la OMS, en la población estudiada 12 se identificaron 243 casos de malnutrición, mientras que en la consulta de crecimiento y desarrollo fueron diagnosticados como casos de malnutrición por los profesionales de salud solo 99. Discusión: La malnutrición es un problema estructural, por ende, se deben tener en cuenta factores tanto intrínsecos como extrínsecos de la persona. Las medidas antropométricas son sólo una manera de medir, que se debe contextualizar con el entorno y las condiciones socioeconómicas, patológicas y culturales en las que se encuentre la población. El estado nutricional de los menores asistentes a los controles de crecimiento y desarrollo de la población estudiada, se encuentra mal registrado, de la misma manera se encontró una gran prevalencia de desnutrición crónica que es un determinante en la calidad de vida. Es imperante la implementación de políticas públicas adecuadas que permitan profundizar en las causas de este flagelo y así mismo en su tratamiento.
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Human bocavirus 1 (HBoV1) is associated with respiratory infections worldwide, mainly in children. Similar to other parvoviruses, it is believed that HBoV1 can persist for long periods of time in humans, probably through maintaining concatemers of the virus single-stranded DNA genome in the nuclei of infected cells. Recently, HBoV-1 was detected in high rates in adenoid and palatine tonsils samples from patients with chronic adenotonsillar diseases, but nothing is known about the virus replication levels in those tissues. A 3-year prospective hospital-based study was conducted to detect and quantify HBoV1 DNA and mRNAs in samples of the adenoids (AD), palatine tonsils (PT), nasopharyngeal secretions (NPS), and peripheral blood (PB) from patients undergoing tonsillectomy for tonsillar hypertrophy or recurrent tonsillitis. HBoV1 was detected in 25.3% of the AD samples, while the rates of detection in the PT, NPS, and PB samples were 7.2%, 10.5%, and 1.7%, respectively. The viral loads were higher in AD samples, and 27.3% of the patients with HBoV had mRNA detectable in this tissue. High viral loads and detectable mRNA in the AD were associated with HBoV1 detection in the other sample sites. The adenoids are an important site of HBoV1 replication and persistence in children with tonsillar hypertrophy. The adenoids contain high HBoV1 loads and are frequently positive for HBoV mRNA, and this is associated with the detection of HBoV1 in secretions.
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Plackett-Burman experimental design was applied for the robustness assessment of GC×GC-qMS (Comprehensive Two-Dimensional Gas Chromatography with Fast Quadrupolar Mass Spectrometric Detection) in quantitative and qualitative analysis of volatiles compounds from chocolate samples isolated by headspace solid-phase microextraction (HS-SPME). The influence of small changes around the nominal level of six factors deemed as important on peak areas (carrier gas flow rate, modulation period, temperature of ionic source, MS photomultiplier power, injector temperature and interface temperature) and of four factors considered as potentially influential on spectral quality (minimum and maximum limits of the scanned mass ranges, ions source temperature and photomultiplier power). The analytes selected for the study were 2,3,5-trimethylpyrazine, 2-octanone, octanal, 2-pentyl-furan, 2,3,5,6-tetramethylpyrazine, and 2-nonanone e nonanal. The factors pointed out as important on the robustness of the system were photomultiplier power for quantitative analysis and lower limit of mass scanning range for qualitative analysis.