Composición química, actividad antioxidante y citotoxicidad de extractos de flores de Magnolia grandiflora L. encontradas en el sureste de México

Many reports state that different structures of M. grandiflora contain bioactive components. Nonetheless, phytochemical studies reported that the extracted essential oils are chemically different and remarkably variable in their qualitative and quantitative compositions. Further studies Mexican M. grandiflora needs to be done. Thus, the research aimed to characterize a) the chemical composition, b) the antioxidant activity and c) cytotoxicity effect of two M. grandiflora flower extracts. The chemical composition was evaluated by preliminary phytochemical test followed by thin layer chromatography, UV-Vis and FTIR spectrophotometer analysis. The antioxidant activity of the flower extracts was measured by the free radical-scavenging activity (ABTS) and the stable radical of 2,2-diphenyl-1-picryl-hydrazyl (DPPH) method and the cytotoxicity by an Artemia salina bioassay. Water and ethyl flower extracts showed the presence of organic chromophores such as flavonoids. Both extracts (ethyl and water) demonstrated antioxidant activity by both ABTS (459.6±8.5 µmol TE g-1 and 274.2±5.7 µmol TE g-1 respectively) and DPPH (3210.4 ± 2.5 µmol TE g-1  and 219.7 ± 0.9 µmol TE g-1  respectively) methologies; and non-cytotoxic activity (LC50 , µg mL-1) (1,285 ± 14  and 1,116 ± 15 respectively). The water and ethyl extracts of M. grandiflora flowers found in southeast Mexico are a promissory source of chemical compounds with attributed biological activity according to the presented results.Muchos estudios afirman que diferentes estructuras de M. grandiflora contienen componentes bioactivos. No obstante, los estudios fitoquímicos indican que los aceites esenciales extraídos son químicamente diferentes y notablemente variables en sus composiciones cualitativas y cuantitativas. Es necesario realizar más estudios sobre M. grandiflora cultivada en México. Por ello, el objetivo de esta investigación fue caracterizar a) la composición química, b) la actividad antioxidante y c) el efecto citotóxico de dos extractos de flores de M. grandiflora. La composición química se evaluó mediante una prueba fitoquímica preliminar seguida de cromatografía en capa fina y análisis espectrofotómetro mediante UV-Vis y FTIR. La actividad antioxidante de los extractos de flores se midió por el método de la actividad reductora de radicales libres (ABTS) y el método de radicales estables de 2,2-difenil-1-picril-hidrazilo (DPPH) y la citotoxicidad por un bioensayo de Artemia salina. Los extractos acuoso y etílico de flores mostraron la presencia de cromóforos orgánicos como los flavonoides. Ambos extractos (etilo y agua) demostraron actividad antioxidante tanto por ABTS (459,6 ± 8,5 µmol TE g-1 y 274,2 ± 5,7 µmol TE g-1 respectivamente) como por DPPH (3210,4 ± 2,5 µmol TE g-1 y 219,7 ± 0,9 µmol TE g-1 respectivamente) metodologías; y actividad no citotóxica (CL50, µg mL-1) (1,285±14 y 1,116±15 respectivamente). Los extractos acuosos y etílicos de las flores de M. grandiflora encontradas en el sureste de México son una fuente promisoria de compuestos químicos con actividad biológica atribuida por los resultados presentados

In vitro trypanocidal activity of nitroimidazole derivatives

Chagas' disease, caused by the protozoan parasite Trypanosoma cruzi, affects 9-12 million of people in Latin America and it is an important cause of heart disease. Although transmission has been reduced, an effective therapy for the infected population is lacking. New isomers nitroimidazole derivatives [4(5)-bromo-1-phenacyl-5(4)-nitroimidazoles] were developed and their antichagasic properties were studied. Five compounds (with different substituents in their aromatic ring) displayed remarkable in vitro activities against T. cruzi. The results demonstrated that 4(5)-bromo-1-(4-methoxiphenacyl)-2-methyl-5(4)- nitroimidazole, 4(5)-bromo-1-(4-chlorophenacyl)-2-methyl-5(4)-nitroimidazole, and 4(5)-bromo-1-(4- cianophenacyl)-2-methyl-5(4)-nitroimidazole have IC50 values of of 3.95, 2.3, and 1.15 μg/mL, respectively, and show acceptable values of cytotoxicity, at concentrations below 5 μg/mL. Our results indicate that mixtures of isomers are a potent inhibitor of T. cruzi growth. The present evidence shows very promising results of new isomers, which emerge as strong candidates for further tests as anti-T. cruzi agents.Colegio de Farmacéuticos de la Provincia de Buenos Aire

A Low Density Microarray Method for the Identification of Human Papillomavirus Type 18 Variants

We describe a novel microarray based-method for the screening of oncogenic human papillomavirus 18 (HPV-18) molecular variants. Due to the fact that sequencing methodology may underestimate samples containing more than one variant we designed a specific and sensitive stacking DNA hybridization assay. This technology can be used to discriminate between three possible phylogenetic branches of HPV-18. Probes were attached covalently on glass slides and hybridized with single-stranded DNA targets. Prior to hybridization with the probes, the target strands were pre-annealed with the three auxiliary contiguous oligonucleotides flanking the target sequences. Screening HPV-18 positive cell lines and cervical samples were used to evaluate the performance of this HPV DNA microarray. Our results demonstrate that the HPV-18’s variants hybridized specifically to probes, with no detection of unspecific signals. Specific probes successfully reveal detectable point mutations in these variants. The present DNA oligoarray system can be used as a reliable, sensitive and specific method for HPV-18 variant screening. Furthermore, this simple assay allows the use of inexpensive equipment, making it accessible in resource-poor settings

Evaluation of Anomalies and Neurodevelopment in Children Exposed to ZIKV during Pregnancy

Zika virus (ZIKV) infection in pregnancy is associated with birth and developmental alterations in infants. In this study, clinical records of 47 infants whose mothers had Zika during pregnancy or clinical manifestations compatible with Zika were reviewed. A description of the infants’ anomalies was established, and a neurodevelopmental assessment was performed on 18 infants, using the Evaluation of Infant Development (EDI for its initialism in Spanish) and DDST-II (Denver Developmental Screening Test II) tests. From his sample, 74.5% of the infants evaluated had major anomalies and 51.9% had minor anomalies. The incidence of major anomalies, related to trimester of pregnancy, was 84.2% for the first trimester, 77.8% for the second trimester, and 37.5% in the third trimester. A similar trend was observed in the frequency of infants without anomalies and was less evident in the incidence of minor anomalies (p = 0.016). Through neurodevelopmental assessments, EDI identified 27.8% of infants as having normal development, while 55.5% of affected infants had developmental delay, and 16.7% were at risk for developmental delay. The DDSST-II showed that 77.7% infants had delay in the gross motor and language area, 88.8% in the fine-adaptative motor area, and 72.2% in the personal–social area. In this work, children of mothers with ZIKV infection during pregnancy may have major or minor anomalies regardless of the trimester of pregnancy in which the infection occurred. The neurodevelopmental assessment shows that ZIKV can cause a developmental delay in infants with the fine-adaptative motor area being the most affected