Dynamics of Polyphenol Biosynthesis by Calli Cultures, Suspension Cultures and Wild Specimens of the Medicinal Plant Ligaria cuneifolia (Ruiz & Pav.) Tiegh. (Loranthaceae). Analysis of Their Biological Activity.

Ligaria cuneifolia (R. et P.) Tiegh. (Loranthaceae) is a South American hemiparasitic species with antioxidant, antitumoral, antimicrobial, and antilipidemic activities attributed to its polyphenolic content. We studied the polyphenolic pattern of L. cuneifolia during different phenological stages: flowering, fruiting, and post-fruiting. The highest total phenolic content was found in stems at post-fruiting (214 ± 12.1 mg gallic acid eq·g-1 DW) and fruiting (209 ± 13.7 mg gallic acid eq·g-1 DW), followed by post-fruiting leaves (207 ± 17.5 mg gallic acid eq·g-1 DW). Flavonoids accumulated at higher levels in leaves and hydroxycinnamic acids in leaves at flowering and post-fruiting. The polyphenolic pattern was similar between organs from wild plants and in vitro cultures, although at a significantly lower level in the latter ones. The performance of calli growing under a 16 h photoperiod in a modified White medium with 1-naphthalene acetic acid (2.50 µM) and Kinetin (9.20 µM) was better than in the dark. When calli grew in media only with auxins (IAA, NAA, and 2,4-D, all at 2.50 µM concentration), its growth and polyphenolic content improved. Cell suspensions with 2.50 µM NAA and 9.20 µM KIN grew slowly and produced very small amounts of polyphenols. As for the antioxidant activity, it was detected in all samples (approximately 1000 µmol trolox eq·g-1 DW) except fruits, where a lower value was found (328 µmol trolox eq·g-1 DW). In vitro cultures have the lowest antioxidant activity when compared to methanolic extracts from organs of wild specimens. Finally, antimutagenic or mutagenic activity in wild plants and in vitro culture extracts was not detected by the Ames test.

Draft Genome Sequences of Burkholderia contaminans FFI-28, a Strain Isolated from a Contaminated Pharmaceutical Solution.

Burkholderia contaminans is a species of the Burkholderia cepacia complex, a group of bacteria that can grow in pharmaceutical products and are capable of infecting the immunocompromised and people with cystic fibrosis. Here, we report draft genome sequences for Burkholderia contaminans FFI-28, a strain isolated from a contaminated pharmaceutical solution.

Antimicrobial Activity of Starch Hydrogel Incorporated with Copper Nanoparticles.

In order to obtain an antimicrobial gel, a starch-based hydrogel reinforced with silica-coated copper nanoparticles (Cu NPs) was developed. Cu NPs were synthesized by use of a copper salt and hydrazine as a reducing agent. In order to enhance Cu NP stability over time, they were synthesized in a starch medium followed by a silica coating. The starch hydrogel was prepared by use of urea and water as plasticizers and it was treated with different concentrations of silica-coated copper nanoparticles (Si-Cu NPs). The obtained materials were characterized by Fourier transform infrared (FT-IR) spectroscopy, electron paramagnetic resonance (EPR) spectroscopy, scanning electron microscopy (SEM), and rheometry. FT-IR and EPR spectra were used for characterization of Cu NPs and Si-Cu NPs, confirming that a starch cap was formed around the Cu NP and demonstrating the stability of the copper nanoparticle after the silica coating step. SEM images showed Cu NP, Si-Cu NP, and hydrogel morphology. The particle size was polydisperse and the structure of the gels changed along with particle concentration. Increased NP content led to larger pores in starch structure. These results were in accordance with the rheological behavior, where reinforcement by the Si-Cu NP was seen. Antimicrobial activity was evaluated against Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacterial species. The hydrogels were demonstrated to maintain antimicrobial activity for at least four cycles of use. A dermal acute toxicity test showed that the material could be scored as slightly irritant, proving its biocompatibility. With these advantages, it is believed that the designed Si-Cu NP loaded hydrogel may show high potential for applications in various clinical fields, such as wound dressings and fillers.

Comparison of the risk of microbiological contamination between samples of breast milk obtained at home and at a healthcare facility.

INTRODUCTION: Breast milk is the best food for preterm infants. Due to their inadequate suction- swallowing action, the administration of expressed breast milk should be done with an orogastric tube. There is little information available regarding the microbiological safety of expressed breast milk. The aim of this article was to evaluate if there were any differences regarding the contamination of breast milk obtained at a healthcare facility versus at home. METHODS: Cross-sectional study that analyzed pairs of breast milk samples (one obtained at home and the other one at a healthcare facility, the same day) from mothers of hospitalized newborn infants with a gestational age =35 weeks. Samples with over 105CFU/mL of mesophilic aerobic bacteria, or with the presence of Escherichia coli, Staphylococcus aureus, Streptococcus faecalis, enterobacterias, Pseudomonas, Salmonella, fungi, and yeast were considered contaminated. RESULTS: A total of 280 breast milk samples (140 pairs) from 53 mothers were analyzed; 139 samples (49.6%; 95% CI: 43.6 to 55.6) were contaminated; contamination was significantly more frequent in the samples obtained at home than in those obtained at a healthcare facility (59.6% versus 39.6%; p = 0.0008; OR 2.25; 95% IC: 1.36 to 3.7). CONCLUSION: Half of the breast milk samples had bacterial growth, which was more frequent in the samples obtained at home than those obtained at a healthcare facility.

Comparison of the risk of microbiological contamination between samples of breast milk obtained at home and at a healthcare facility / Comparación del riesgo de contaminación de la leche materna extraída en una unidad de cuidados intensivos neonatales y en el hogar

Introduction. Breast milk is the best food for preterm infants. Due to their inadequate suction- swallowing action, the administration of expressed breast milk should be done with an orogastric tube. There is little information available regarding the microbiological safety of expressed breast milk. The aim of this article was to evaluate if there were any differences regarding the contamination of breast milk obtained at a healthcare facility versus at home. Methods. Cross-sectional study that analyzed pairs of breast milk samples (one obtained at home and the other one at a healthcare facility, the same day) from mothers of hospitalized newborn infants with a gestational age =35 weeks. Samples with over 105CFU/mL of mesophilic aerobic bacteria, or with the presence of Escherichia coli, Staphylococcus aureus, Streptococcus faecalis, enterobacterias, Pseudomonas, Salmonella, fungi, and yeast were considered contaminated. Results. A total of 280 breast milk samples (140 pairs) from 53 mothers were analyzed; 139 samples (49.6%; 95% CI: 43.6 to 55.6) were contaminated; contamination was significantly more frequent in the samples obtained at home than in those obtained at a healthcare facility (59.6% versus 39.6%; p = 0.0008; OR 2.25; 95% IC: 1.36 to 3.7). Conclusion. Half of the breast milk samples had bacterial growth, which was more frequent in the samples obtained at home than those obtained at a healthcare facility.

Introducción. La leche materna es el mejor alimento para los prematuros. Debido a su inadecuado mecanismo de succión-deglución, la administración de leche materna extraída debe realizarse mediante una sonda orogástrica. Se dispone de escasa información sobre las condiciones microbiológicas de seguridad para la leche materna extraída. El objetivo del presente trabajo fue evaluar si había diferencia en la contaminación de la leche extraída en la institución y en el domicilio. Métodos. Estudio transversal que analizó pares de muestras de leche (una extraída en el hogar y otra en la institución, el mismo día) de madres de neonatos internados, de edad gestacional = 35 semanas. Se consideraron contaminadas las muestras de leche que tenían más de 105 UFC/ml de aerobios mesófilos, o presencia de Escherichia coli, Staphylococcus aureus, Streptococcus faecalis, enterobacterias, Pseudomonas, Salmonella, hongos y levaduras. Resultados. Se analizaron 280 muestras de leche (140 pares) de 53 madres; 139 muestras (49,6%; IC 95%: 43,6 a 55,6) presentaron contaminación, que fue significativamente más frecuente en las muestras obtenidas en el domicilio que en las obtenidas en la institución (59,6% contra 39,6%; p= 0,0008; OR 2,25; IC 95% 1,36 a 3,7). Conclusión. La mitad de las muestras de leche materna presentaron contaminación, la cual fue más frecuente en las obtenidas en el domicilio.

Triclosan-loaded poloxamine micelles for enhanced topical antibacterial activity against biofilm.

Our research group is interested in the study of different technological approaches to treat hospital biofilm as a means to constrain nosocomial-acquired infections. The present work investigated the effect of the incorporation of the antibacterial agent triclosan (TS) into polymeric micelles of poloxamine T1107 (MW=15 kDa, 70 wt% PEO). The aggregation phenomenon was primarily investigated by means of Critical Micellar Concentration in a broad range of pH. Then, the effect of the polymer concentration on the micellar size was evaluated by Dynamic Light Scattering. Solubility levels increased up to 4 orders of magnitude. The drug inclusion affected the micellization, resulting in size increase and micellar fusion. This phenomenon was only apparent in TS-saturated systems. TS-loaded aggregates proved to be active in vitro against a broad spectrum of bacteria but more importantly, also against two representative clinical pathogens: methicilin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecalis (VREF). While the former was sensitive to even very low TS levels attainable in poloxamine-free aqueous media, the later was inhibited only when exposed to higher drug levels affordable exclusively using an inclusion system. These findings indicated the release of the drug from the reservoir. Finally, the activity of a TS-containing 5% poloxamine combination of pH 7.4 was assessed on biofilms of Staphylococcus epidermidis. Results showed a significant decrease (p<0.001) in the number of Colony-Formation Units when the biofilm was exposed to the TS/poloxamine as compared to the limited activity of the polymer-free TS control.