Microbiological Diversity and Associated Enzymatic Activities in Honey and Pollen from Stingless Bees from Northern Argentina.

Honey and pollen from Tetragonisca fiebrigi and Scaptotrigona jujuyensis, stingless bees from northern Argentina, presented a particular microbiological profile and associated enzymatic activities. The cultured bacteria were mostly Bacillus spp. (44%) and Escherichia spp. (31%). The phylogenetic analysis showed a taxonomic distribution according to the type of bee that was similar in both species. Microbial enzymatic activities were studied using hierarchical clustering. Bacillus spp. was the main bacterium responsible for enzyme production. Isolates with xylanolytic activity mostly presented cellulolytic activity and, in fewer cases, lipolytic activity. Amylolytic activity was associated with proteolytic activity. None of the isolated strains produced multiple hydrolytic enzymes in substantial amounts, and bacteria were classified according to their primary hydrolytic activity. These findings add to the limited knowledge of microbiological diversity in honey and pollen from stingless bees and also provide a physiological perspective of this community to assess its biotechnological potential in the food industry.

Oenococcus oeni allows the increase of antihypertensive and antioxidant activities in apple cider.

This study aimed to investigate the impact of the malolactic fermentation (MLF) carried out by Oenococcus oeni on antihypertensive and antioxidant activities in cider. The MLF was induced using three strains of O. oeni. The modification in phenolic compounds (PCs) and nitrogen organic compounds, antioxidant, and antihypertensive activities were determined after MLF. Among the 17 PCs analyzed caffeic acid was the most abundant compound and phloretin, (-)-epicatechin, and myricetin were detected only in malolactic ciders, however, (-)-epigallocatechin was not detected after MLF. The evaluation of nitrogen organic compounds revealed a drop in total protein concentration (from 17.58 to 14.00 mg N/L) concomitantly with a significant release of peptide nitrogen (from 0.31 to a maximum value of 0.80 mg N/L) after MLF. In addition, an extracellular proteolytic activity was evidenced in all MLF supernatants. The FRAP activity increased reaching a maximum of 120.9 µmol FeSO4/mL and the ABTS radical-scavenging activity increased until 6.8 mmol ascorbic acid/L. Moreover, the angiotensin I-converting enzyme inhibitory activity reached a maximum value of 39.8%. The MLF conducted by O. oeni in ciders enables the increase of interesting biological activities and this finding could constitute a valuable tool to add value to final product.

Geoffroea decorticans fruit extracts inhibit the wnt/ß-catenin pathway, a therapeutic target in cancer.

Geoffroea decorticans (chañar) is commonly used for culinary and medicinal purposes in rural communities. The aim of this work was to chemically characterize three Geoffroea decorticans extracts and determine their capacity to modulate the wnt/ß-catenin pathway. This signaling pathway plays a key role in embryonic development but its overactivation leads to cancer cell growth. Phytochemical analysis of extracts showed presence of major classes of phytochemicals. Gas chromatography-mass spectrometry results revealed the presence of acids, esters and furanic compounds. Using Xenopus embryos as in vivo model organisms, we found that the extracts modulated dorso-ventral axis formation and rescued hyperdorsalized phenotypes produced by LiCl treatment. In agreement with these findings, Geoffroea decorticans extracts decreased ß-catenin levels and suppressed the expression of wnt target genes such as xnr3 and chordin, thus demonstrating an inhibitory regulation of the wnt/ß-catenin signaling pathway. All these results support a new role for Geoffroea decorticans fruit derivatives with possible anti-carcinogenic actions.

Trypanocidal activity of South American Vernonieae (Asteraceae) extracts and its sesquiterpene lactones.

Chagas disease is caused by Trypanosoma cruzi and affects the poorest population in the Americas. Fourteen plant extracts and seventeen sesquiterpene lactones from the tribe Vernonieae (Asteraceae), were evaluated for the first time against T. cruzi. Cytotoxicity employing HeLa cells was also assessed. The best results were obtained with leaves and flowers rinse extracts from Vernonanthura nebularum (E-1 and E-3) and Elephantopus mollis (E-11 and E-13), with IC50 values <2 µg/mL, being E-1 the most active (IC50 = 0.8 µg/mL). Additionally, these extracts displayed a good selectivity (SI > 10). The most active sesquiterpene lactones, isolated from the extracts, were 2 (2-methoxy-2,5-epoxy-8-methacryloxygermacra-3Z,11(13)-dien-6,12-olide) and 6 (2-ethoxy-2,5-epoxy-8-angeloxygermacra-3Z,11(13)-dien-6,12-olide) from V. nebularum and 12 (8α-methacryloxyhirsutinolide 13-O-acetate) from V. pinguis, with IC50 of 1.5, 2.1 and 2.0 µM, respectively. These compounds showed SI values >14, better than those of the reference drug nifurtimox. Plants living in South American ecosystems could become a potential source of trypanocidal agents.

Insecticidal effects of Vernonanthura nebularum against two economically important pest insects.

Vernonanthura nebularum (Cabrera) H. Rob. (Asteraceae), an endemic species from the north of Argentina, is a rich source of elephantopus-type sesquiterpene lactones. These compounds have proved to be promising antiparasitic agents, but there is no report about their action against pest insects. In this work we studied for the first time the antifeedant and toxic effects of V. nebularum natural products against the fall army warm Spodoptera frugiperda Smith and the oviposition deterrent activity against the fruit fly Ceratitis capitata Wiedemann. As a result, we found that extracts, fractions composed of sesquiterpene lactones and pure sesquiterpene lactones altered larval feeding behavior in the food choice test. Nutritional parameters of S. frugiperda larvae were also affected. Fraction II (300 µg/g of diet.), containing compounds 1, 2 and 3, was the most toxic substance with 80% pupal mortality and wing malformations in adults. In oviposition deterrent experiments against Ceratitis capitata, we observed a moderate effect at 30 µg/cm2 of the test compound. The most active substances were the methanolic extract, dichloromethane subextract and lactone 2. According to our results, V. nebularum natural products could be used for maximizing the effectiveness and specificity in future insecticide design with specific or multiple target sites, while ensuring the economic and ecological sustainability, in addition to combat the increasing resistance rates developed by synthetic pesticides.

Active sesquiterpene lactones against Leishmania amazonensis and Leishmania braziliensis.

Seventeen sesquiterpene lactones (SLs) isolated from five species of the tribe Vernonieae were evaluated for their in vitro activity against promastigotes of Leishmania amazonensis and Leishmania braziliensis. Additionally, a quantitative structure activity relationship has been made, since all these natural compounds were found to have potent to mild antileishmanial properties. The most active compounds against L. braziliensis were 16 and 17 (IC50 values 1.45 and 1.34 µM, respectively), followed by compound 15 with IC50 value of 1.60 µM against L. amazonensis. The three glaucolide-type SLs (4-6) were the least active against both parasites. The computational study allowed us to establish that lipophilicity and polarisability play an important role in the antiparasitic activity. This is the first report of the known germacradiendiolides 16 and 17 from Elephantopus mollis. The activity data of the compounds 1-17 assayed against Leishmania parasites are reported here for the first time.

Formación de habilidades profesionales durante el tercer año de la Carrera de Estomatología / Formation of professional skills during the third academic year of the Dentistry Major

Introducción: el desarrollo de habilidades profesionales en la carrera de estomatología con carácter sistémico e interdisciplinario ha garantizado un proceso de formación adecuado. Objetivo: valorar el enfoque sistémico del proceso de formación de habilidades profesionales en el tercer año de la carrera de estomatología. Material y método: se estudió la totalidad del claustro del tercer año de la carrera de estomatología de la filial en Pinar del Río en el curso 2013-2014, compuesto por 22 profesores, seleccionado de manera intencional, los estudiantes pertenecientes al tercer año (28) y los del cuarto año (38), que fue considerado grupo referencial del proceso. En ambos casos seleccionados de manera intencional. Estudio sustentado en el método dialéctico materialista por su capacidad de integrar lo cualitativo y lo cuantitativo y que permitió determinar el sistema de métodos a usar, por lo que se emplearon métodos del nivel teórico, del nivel empírico y métodos estadísticos. Resultados: se evidenció la falta de enfoque sistémico del proceso de formación de habilidades profesionales en la carrera, la no interrelación de dicho proceso y su tributo al perfil del egresado, carencia de trabajo metodológico dirigido a este proceso y la no participación activa del estudiantado. Los resultados fueron analizados en términos porcentuales. Conclusiones: no se concreta la definición de habilidades por asignaturas que tributen al modelo del profesional y modos de actuación, no existe participación integrada del claustro en el proceso de formación de habilidades profesionales ni participación activa de los estudiantes.

Introduction: the development of professional skills in the Dentistry major, with a systemic and interdisciplinary approach, has ensured a proper training process. Objective: to evaluate the systemic approach in the formation of professional skills in the third academic year of the Dentistry major. Material and method: the Dentistry campus' entire faculty of the third academic year of the Dentistry major in Pinar del Río was study in the period 2013-2014, as being composed of 22 professors, intentionally chosen, the third and forth years students (23 and 28, respectively), considered as referential group of the process, in both cases intentionally chosen. This study is supported by the dialectical materialist method for its ability to integrate the qualitative and the quantitative and for it allowed to determine the system of methods to be used, namely: methods from the theoretical and empirical levels, and also statistical methods. Results: it was evinced the lack of systemic approach to the process of formation of professional skills in the major, no interrelation of the process and its contribution to the graduate's profile, the lack of methodological work aimed at the process and not to the active participation of the students. The results were analyzed in percentage terms. Conclusions: the definition of skills is not determined for each subject contributing with the professional's model and performance way. There is neither integrated participation by the faculty in the process of professional skills formation nor active participation by the students.

Chalcones in bioactive Argentine propolis collected in arid environments.

The aim of this study was to assess the chemical and biological profile of propolis samples collected in arid environments of north-western Argentina. The samples were from two phytogeographical regions (Prepuna and Monte de Catamarca Province). Propolis ethanolic extracts (PEE) and chloroform (CHL), hexane (HEX) and aqueous (AQ) sub-extracts of samples from three regions (CAT-I; CAT-II and CAT-III) were obtained. All PEE exhibited antioxidant activity in the DPPH radical scavenging assay (SC50 values between 28 and 43 microg DW/mL). The CHL extract was the most active (SC50 values between 10 and 37 microg DW/mL). The antioxidant activity in the beta-carotene bleaching assays was more effective for PEE and CHL (IC50 values between 2 and 9 microg DW/mL, respectively). A similar pattern was observed for antibacterial activity. The highest inhibitory effect on the growth of human Gram-positive bacteria was observed for CHL-III and CHL-I (Monte region) with minimal inhibitory concentration values (MIC100) of 50 to 100 microg DW/mL. Nine compounds were identified by HPLC-PAD. Two of them (2', 4'- dihydroxychalcone and 2',4'- dihydroxy 3'-methoxychalcone) were found only in propolis samples from the Monte phytogeographical region. We consider that the Argentine arid region is appropriate to place hives in order to obtain propolis of excellent quality because the dominant life forms in that environment are shrubby species that produce resinous exudates with a high content of chalcones, flavones and flavonols.

Chemical composition of Argentinean propolis collected in extreme regions and its relation with antimicrobial and antioxidant activities.

This paper reveals, for the first time, the functional properties of propolis from an extreme region of Argentine (El Rincón, Province of Catamarca, Argentina), as well as the isolation and identification of bioactive compounds. The antioxidant activity was determined by the ABTS method and beta-carotene bleaching. The antibacterial activity was determined on methicillin resistant Staphylococcus aureus (MRSA) by the microdilution method and bioautographic assays. Twelve compounds were isolated and identified by NMR spectroscopy. The main bioactive compounds were 2',4'-dihydroxy-3'-methoxychalcone (3), 2',4'-dihydroxychalcone (9), 2',4',4-trihydroxy-6'- methoxychalcone (8), 5-hydroxy-4',7-dimethoxyflavone (4), 4',5-dihydroxy-3,7,8-trimethoxyflavone (10) and 7-hydroxy- 5,8-dimethoxyflavone (11). All compounds were active against clinical isolates (MIC50 10 microg/mL) and displayed antioxidant activity (SC50 values of 20 microg/mL). The MIC and SC50 values of the isolated compounds were lower than those obtained with crude propolis extracts, chloroform sub-extracts and isolated fractions.

Effect of seasonal variations and collection form on antioxidant activity of propolis from San Juan, Argentina.

Propolis was included in the Argentine Food Code as a functional food. The chemical parameters and antioxidant properties of propolis samples from the same colonies of Apis mellifera in San Juan (Cuyo region, Western Argentine) were compared every month for 1 year using two collection methods. Chemical parameters were analyzed by the spectrophotometric method and fingerprinting using high-performance liquid chromatography with ultraviolet detection. The antioxidant activities of propolis samples were measured using model systems including the analysis of the scavenging activities for 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals and the beta-carotene bleaching assay. The results showed that propolis had a higher free radical scavenging and lipid peroxidation inhibitory capacity than butylated hydroxytoluene and quercetin, antioxidants used in the pharmaceutical and food industries. The concentration required to scavenge 50% of free radicals (SC(50)) values differed depending on the sample collection month. Samples collected in November had the highest antioxidant capacity. In all cases, SC(50) values of propolis samples obtained by scraping were similar to those collected from a wire mesh (5 microg/mL for ABTS and 20-30 microg/mL for DPPH radicals). A significant positive correlation was found between the antioxidant capacity and flavonoid content of each analyzed extract. The chemical profiles were very similar. Galangin (3,5,7-trihydroxyflavone), an antioxidant compound, was detected in all samples as a major compound. The chromatographic profile suggests that of Baccharis sp., which would be one of the botanical sources of propolis from western Argentina, and the content of galangin can be used as a parameter for evaluating propolis quality. Our results suggest that Argentine propolis from Cuyo is a promising source of bioactive compounds as ingredients for developing functional foods with a beneficial impact on oxidative stress.

Eudesmanes from Pluchea sagittalis. Their antifeedant activity on Spodoptera frugiperda.

Eudesmane-type sesquiterpenoids 3alpha-(2,3-epoxy-2-methylbutyryloxy)-4alpha-formoxy-11-hydroxy-6,7-dehydroeudesman-8-one (1) and 3alpha-(2,3-epoxy-2-methylbutyryloxy)-4alpha,7alpha,11-trihydroxyeudesman-8-one (2), together with 10 known structurally related eudesmanes were isolated from the CHCl3 extract of aerial parts of Pluchea sagittalis (Lamarck) Cabrera. Their structures were deduced by extensive application of 1 and 2D NMR spectroscopic techniques and high and low resolution CIMS. X-ray crystallographic analysis of the known compound 3alpha-(2,3-epoxy-2-methylbutyryloxy)-4alpha-formoxycuauthemone (9) is reported here for the first time, and confirms the structural features for the series of the reported eudesmanes. All eudesmanes were tested for their antifeedant activity by incorporating them to an artificial diet of larvae of the polyphagous insect Spodoptera frugiperda at a concentration of 100ppm. Our results, from feeding choice tests, indicated that most of the compounds deter larval feeding at the cited concentration.

Toxicity and synergism in the feeding deterrence of some coumarins on Spodoptera frugiperda Smith (Lepidoptera: Noctuidae).

The phagodepression activity of five coumarins (= 2H-1-benzopyran-2-ones), 6-hydroxy-7-isoprenyloxycoumarin (1), 6-methoxy-7-isoprenyloxycoumarin (2), 6,7-methylenedioxycoumarin (3), 5-methoxy-6,7-methylenedioxycoumarin (4), and 6-methoxy-7-(2-hydroxyethoxy)coumarin (5), from the Argentine native herb Pterocaulon polystachyum, was tested against Spodoptera frugiperda (Lepidoptera: Noctuidae) larvae. Two analogs, scopoletin (6) and 2-methoxy-2-methyl-3,4,5,6,7,8-hexahydro-3H-chromen-5-one (7), synthesized in our laboratory, were also evaluated for comparison. The compounds were added to an artificial diet at doses ranging from 50 to 200 microg per g of diet. Natural coumarins induced 100% of phagodepression when 200 microg were added per g of diet. Binary equimolar mixtures of the natural coumarins were phagodepressors against S. frugiperda surpassing the expected additive responses, indicating that these compounds can act synergistically against S. frugiperda larvae. Compounds 1 and 3 (non-methoxylated coumarins), and the equimolar mixture of both, displayed the strongest phagodepression. Additionally, 50 microg/g of 1 and 3 incorporated to the larval diet caused 80 and 50% of pupal mortality, respectively, while a 100 microg/g dose of compounds 2, 4, 6, and 7 produced 60, 50, 10, and 80% pupal mortality, respectively. Larval growing rate during the early larval instars was significantly reduced by treatments with the methylenedioxycoumarins 3 and 4. Coincidentally, the larval period duration was significantly increased by the latter compounds.

La colección Autoayuda y la promoción de salud / The Self-help collection and the promotion of health

La Editorial Oriente de la provincia de Santiago de Cuba, defiende como su principal proyección ofrecer a los autores y lectores los títulos que sobresalgan por su calidad y profesionalidad, de manera que cada libro sea un objeto bello por su forma y útil por su contenido. Esta casa editora incluye en la Colección Autoayuda la cual se muestra en el presente trabajo documentos que además de reunir las citadas características contribuyen a promover la salud y prevenir enfermedades en la población

Cistadenoma microquístico del pancreas como hallazgo incidental: presentación de un caso y revisión de la literatura / Microcyst cystoadenoma of pancreas how incidental to detect: presentation of a case and review of the literature

Se presenta el caso de una paciente de 79 años de edad en plan quirúrgico de prolapso genital a quien se le descubrió incidentalmente la presencia de una masa Reproperitoneal durante estudio rutinario de ecosonografia abdominal, confirmada por TAC abdominal. La punción con aguja fina guiada por TAC reveló posible lesión benigna. El estudio histológico de la pieza quirúrgica demostró Cystoadenoma Microquístico del Pancreas. Se discute el diagnóstico, incidencia y tipos de Neoplasias Pancreáticas Quísticas

Lesión de dieulafoy una causa oculta de sangrado gastrointestinal: presentación de un caso y revisión de la literatura / Injuries of dieulafoy cause occulta of gastroientestinal hemorrhage: presentation of a case and review of the literature

Se presenta el caso de un paciente de sexo masculino, de 80 años de edad con Hemorragia Digestiva Superior recurrente no masiva de origen oculto, descubriéndose Lesión de Dieulafoy posterior a un episodio de Hemorragia Digestiva Mesiva, tratada exitosamente con Esclerosis. Se hace hincapié en la necesidad de realizar Endoscopia de dichas lesiones y su importancia como herramienta de diagnóstico y control post-esclerosis. La resección precisa en cuña de este caso, fue precedida de tatuaje de la zona de esclerosis ya estudiada por Eco-endoscopia. Un control al año ha demostrado ausencia de recurrencia

Divertículo duodenal penetrado que simula neoplasia de cabeza de páncreas y revisión de la literatura: (presentación atípica) / Duodenal discerner diverticulo that simulation pancreas head neoplasia and literature review: (atypical presentation)

Se analiza a propósito de un caso de divertículo duodenal de diagnóstico difícil la importancia de realizar una evaluación integral, debido a que cada exploración se le debe dar su justo valor y todas se complementan. En este caso la endoscopia digestiva superior y el estudio radiológico fueron el patrón de oro del diagnóstico, aunque por lo anteriormente expuesto se evidencia que se le acreditó más importancia al ultrasonido abdominal y a la tomografía axial computarizada en los que se diagnosticó una lesión compatible con una neoplasia de cabeza de páncreas por lo que fue intervenida quirúrgicamente

Revisión sobre contusión cardíaca con resultados de la experiencia clínica de la UCI del Centro Médico de Caracas / Review about cardiac contussion with results from clinical experience of the UCI of the Centro Médico de Caracas

El trauma cardíaco representa una Entidad no diagnosticada con su verdadera frecuencia. Se practicó un estudio prospectivo en nuestra Unidad de Cuidados Intensivos que incluyó 79 pacientes Politraumatizados, de los cuales 23 presentaron evidencia de trauma torácico y 17 presentaron signos sugestivos de contusión cardíaca. 53% de los pacientes con contusión miocárdica tuvieron un traumatismo de tórax severo. 65% de los pacientes con contusión miocárdica presentaron manifestaciones clínicas de las cuales las arritmias fueron las más frecuentes. Las alteraciones electrocardiográficas más frecuentes fueron: inversión de la Onda T en 41%, desnivel ST 17%, Onda Q en D2, D3 y AVF en 17%. La ecocardiografía bidimensional y la gammagrafía cardíaca, en nuestro estudio, no contribuyeron en aumentar el diagnóstico de contusión miocárdica. Nuestros resultados fueron similares a los ya publicados por otros autores