Effects of Dimerization on the Structure and Biological Activity of Antimicrobial Peptide Ctx-Ha

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Mechanism of Action and Relationship Between Structure and Biological Activity of Ctx-Ha: A New Ceratotoxin-like Peptide from Hypsiboas albopunctatus

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Comparison of crystallinity between natural hydroxyapatite and synthetic cp-Ti /HA coatings

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Associacao de opioides lipofilicos a bupivacaina na anestesia peridural. Ha vantagem no aumento da dose do opioide?

Background and Objectives: - The effects of associating lipophilic opioids to local anesthetics in epidural anesthesia are not well defined. There are still questions and controversies about opioid doses to be used and their major effects in the epidural block. This study aimed at evaluating the epidural block effects in humans of the association of different fentanyl and sufentanil doses to bupivacaine with 1:200.000 epinephrine. Methods: - A double-blind randomized study was performed in 94 patients of both genders, physical status ASA I, aged between 18 and 60 years, submitted to lower abdomen, perineal or lower limb surgery. Patients without preanesthetic medication were epidurally injected with 100 mg (20 ml) 0.5% bupivacaine, 0.1 mg (0.1 ml) 1%o epinephrine plus a combination of the following drugs: BUPI Group (15 patients): 2 ml of 0.9% saline solution (SS); FENT50 Group (19 patients): 50 μg (1 ml) fentanyl + 1 ml SS; FENT100 Group (20 patients): 100 μg (2 ml) fentanyl; SUF30 Group (20 patients): 30 μg (0.6 ml) sufentanil + SS (1.4 ml); SUF100 Group (20 patients): 50 μg (1 ml) sufentanil + SS (1 ml). The following parameters were studied: onset of sensory block, analgesic block (onset time) in T12, T10 and T8, analgesic block duration in T10 and T12, motor block degree, consciousness degree, need for supplemental perioperative sedation and analgesia, hypotension, bradycardia and peri and post operative side-effects, analgesia duration, proportion of patients needing supplemental analgesia and evaluation of postoperative pain (pain analog visual scale). Results: Groups were demographically uniform. The addition of fentanyl or sufentanil did not alter major characteristics of perioperative epidural block and has not significantly increased postoperative analgesia duration as compared to the use of bupivacaine only. However, the addition of lipophilic opioids has increased the quality of perioperative anesthetic block, translated into a lesser need for supplemental analgesia (p < 0.02). The increased dose of fentanyl and especially of sufentanil has increased the incidence of perioperative drowsiness (p < 0.001) without significant increase in other side effects. Conclusions: In the conditions and doses used, the addition of lipophilic opioids to bupivacaine and the increased dose of lipophilic opioids have improved anesthetic block quality without changes in the epidural block characteristics or a significant increase in side effects, with the exception of drowsiness mainly caused by sufentanil. However, they were not able to provide a significant increase in postoperative analgesia duration.

Los mercados en el Istmo Centroamericano y México: ¿qué ha pasado con la competencia?

Incluye Bibliografía

El sector financiero en América Latina: ha llegado la hora de consolidar el marco institucional

Incluye Bibliografía

Los mercados en el Istmo Centroamericano y México: ¿qué ha pasado con la competencia?

Incluye Bibliografía

La familia desde la cultura. ¿Qué ha cambiado en América Latina?

Incluye Bibliografía

Pueblos indígenas de América Latina: políticas y programas de salud, ¿cuánto y cómo se ha avanzado? Informe del Seminario-Taller

Incluye Bibliografía

La apertura comercial ¿ha creado paraísos de contaminadores en América Latina?

Incluye Bibliografía

Dynamics and Conformational Studies of TOAC Spin Labeled Analogues of Ctx(Ile21)-Ha Peptide from Hypsiboas albopunctatus

Antimicrobial peptides (AMPs) isolated from several organisms have been receiving much attention due to some specific features that allow them to interact with, bind to, and disrupt cell membranes. The aim of this paper was to study the interactions between a membrane mimetic and the cationic AMP Ctx(Ile21)-Ha as well as analogues containing the paramagnetic amino acid 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid (TOAC) incorporated at residue positions n = 0, 2, and 13. Circular dichroism studies showed that the peptides, except for [TOAC13]Ctx(Ile21)-Ha, are unstructured in aqueous solution but acquire different amounts of α-helical secondary structure in the presence of trifluorethanol and lysophosphocholine micelles. Fluorescence experiments indicated that all peptides were able to interact with LPC micelles. In addition, Ctx(Ile21)-Ha and [TOAC13]Ctx(Ile21)-Ha peptides presented similar water accessibility for the Trp residue located near the N-terminal sequence. Electron spin resonance experiments showed two spectral components for [TOAC0]Ctx(Ile21)-Ha, which are most likely due to two membrane-bound peptide conformations. In contrast, TOAC2 and TOAC13 derivatives presented a single spectral component corresponding to a strong immobilization of the probe. Thus, our findings allowed the description of the peptide topology in the membrane mimetic, where the N-terminal region is in dynamic equilibrium between an ordered, membrane-bound conformation and a disordered, mobile conformation; position 2 is most likely situated in the lipid polar head group region, and residue 13 is fully inserted into the hydrophobic core of the membrane. © 2013 Vicente et al.

Desigualdad de los ingresos en el Brasil. ¿Qué ha cambiado en los últimos años?

En este estudio se presentan datos empíricos que permiten evaluar la repercusión de diversas variables socioeconómicas y políticas en distintas formas de medir la desigualdad de los ingresos en las 27 unidades de la República Federativa del Brasil entre 1999 y 2008. La experiencia brasileña resulta útil para entender las políticas relativas a la desigualdad de los ingresos en los países en desarrollo. Los resultados indican que el progreso observado durante el período analizado se debe a la combinación de una mayor apertura comercial, el desarrollo tecnológico y financiero, la reducción de la tasa de desempleo, la puesta en práctica de políticas sociales con efecto directo en las familias más pobres y la implementación de mecanismos contra la corrupción.

La evolución del ingreso de los hogares en América Latina durante el período 1990-2008: ¿Ha sido favorable a los pobres?

Una misma tasa de crecimiento del ingreso genera efectos de distinta magnitud en la pobreza y en la desigualdad. Esto sugiere aplicar metodologías complementarias para valorar si la estrategia de desarrollo ha generado variaciones del ingreso, la pobreza y la equidad en favor de los pobres. En este trabajo se aplican distintas metodologías para calificar la calidad del crecimiento del ingreso en los países de América Latina durante el período 1990-2008.

El gran desafío para los puertos: la hora de pensar una nueva gobernanza portuaria ha llegado

El presente Boletín FAL constituye la primera parte de una serie de estudios sobre puertos y transporte marítimo. Se analizan los cambios en la gobernanza portuaria que han ocurrido desde el inicio de la última ola de reformas, y las nuevas circunstancias en las que se encuentra el sistema portuario, de lo que surge la necesidad de orientar una nueva gobernanza en los puertos de América Latina y el Caribe con el fin de hacer frente a los requerimientos del siglo XXI.