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CuO and ZnO nanoparticles (NPs) were synthesized at room-temperature following a novel, direct, high-yield (>91%) and green method based on a mechanically activated metathesis reaction. The CuO-NPs exhibited a rod-like shape with average length and diameter of 22 and 6 nm, respectively, while the ZnO-NPs showed spherical-like morphology and mean diameter of 15 nm, as determined by TEM. The antimicrobial properties of the NPs and commercially available micrometric counterparts were evaluated by the micro dilutions method to determine the minimum inhibitory concentrations against reference strains from ATCC microorganisms, which were representative of the main groups of bacteria related to human infections, such as E. coli, S. aureus, E. faecalis and P. aeruginosa. The CuO and ZnO-NPs showed better antibacterial properties (500 μg/mL) in comparison with the commercial micrometric particles (1000 μg/mL). The analysis of the synergism between both NPs and ampicillin showed a decrease of their concentrations against all the microorganisms studied, with the ZnO-NPs showing better synergism activity than CuO-NPs, whereas the combination of the antibiotic with ZnO-NPs showed a six-fold decrease against all the microorganisms studied except to P. aeruginosa. The FIC index was calculated with both NPs and ampicillin to each bacterium. In most cases, the effect was partial synergism, and an additive effect was achieved when those combinations were evaluated against P. aeruginosa. The cell viability tests showed that the CuO and ZnO-NPs synthesized and mixed with the antibiotic are biocompatible in effective doses (

espanolIntroduccion: La anemia se considera una entidad de mayor prevalencia en paises en vias de desarrollo, teniendo como causas principales la falta de ingesta nutricional: hierro, acido folico, vitamina B12. La anemia ferropenica es la causa mas frecuente y afecta en su mayoria a mujeres en edad fertil como en la postmenopausia. Ademas se ha asociado a Helicobacter pylori, como factor de riesgo para anemia ferropenica. Objetivo: Determinar la asociacion que existe entre la anemia y Helicobacter pylori como factor de riesgo en los estudiantes de la Universidad Peruana Union en el ano 2014. Materiales y metodos: Estudio de casos y controles. Este trabajo se llevo a cabo en estudiantes de la Universidad Peruana Union. Se obtuvo la base de datos de estudiantes atendidos en la Clinica Good Hope, con los diagnosticos de anemia ferropenica, seleccionados por medio de un muestreo aleatorio simple determinando el grupo caso de 40 personas con anemia (n=40) y 80 personas sin diagnostico de anemia siendo el grupo control. Se aplico una encuesta con las variables de interes para la descripcion de la poblacion y el analisis de muestra sanguinea para el hematocrito, hemoglobina (en 48 personas para confirmar los casos y controles) y la prueba rapida anti-Helicobacter pylori. Resultados: Se determino un odds ratio entre anemia y Helicobacter pylori de 3,8; un chi cuadrado de 10,12 y una p=0,001. Este resultado rechaza la hipotesis nula de independencia de las variables y se comprueba la asociacion antes propuesta. Discusion: Helicobacter pylori es un factor de riesgo asociado a la anemia ferropenica, aunque se requiere mas estudios en nuestra poblacion. Conclusiones: Helicobacter pylori es un factor de riesgo asociado con anemia, aunque se requieren mas estudios en la poblacion de esta investigacion. EnglishIntroduction: Anemia is considered an entity of greater prevalence in developing countries, having as main causes the lack of nutritional intake: iron, folic acid, vitamin B12. Iron deficiency anemia is the most frequent cause and affects mostly women of childbearing age as in postmenopause. It has also been associated with Helicobacter pylori as a risk factor for iron deficiency anemia. Objective: To determine the association that exists between anemia and Helicobacter pylori as a risk factor in the students of the Peruvian Union University in 2014. Material and Methods: Cases and controls study. This work was carried out on students of the Union Peruvian University. The database of students attended at the Good Hope Clinic was obtained, with the diagnoses of irondeficiency anemia, selected by means of a simple random sampling, determining the group of 40 people with anemia (n = 40) and 80 people without diagnosis of anemia being the control group. A survey was applied with the variables of interest for the description of the population and the blood sample analysis for the hematocrit, hemoglobin (in 48 people to confirm the cases and controls) and the rapid anti-Helicobacter pylori test. Results: An odds ratio between anemia and Helicobacter pylori of 38 was determined; a square chi of 10.12 and a p = 0.001. This result rejects the null hypothesis of independence of the variables and the previously proposed association is checked. Discussion: Helicobacter pylori is a risk factor associated with iron deficiency anemia, although more studies are required in our population. Conclusions: Helicobacter pylori is a risk factor associated with anemia, although more studies are required in the population of this research.

Background Kinetic modeling and control analysis of a metabolic pathway may identify the steps with the highest control in tumor cells, and low control in normal cells, which can be proposed as the best therapeutic targets. Methods Enzyme kinetic characterization, pathway kinetic modeling and control analysis of the glucose central metabolism were carried out in rat (hepatoma AS-30D) and human (cervix HeLa) cancer cells and normal rat hepatocytes. Results The glycogen metabolism enzymes in AS-30D, HeLa cells and hepatocytes showed similar kinetic properties, except for higher AS-30D glycogen phosphorylase (GP) sensitivity to AMP. Pathway modeling indicated that fluxes of glycogen degradation and PPP were mainly controlled by GP and NADPH consumption, respectively, in both hepatocytes and cancer cells. Likewise, hexose-6-phosphate isomerase (HPI) and phosphoglucomutase (PGM) exerted significant control on glycolysis and glycogen synthesis fluxes in cancer cells but not in hepatocytes. Modeling also indicated that glycolytic and glycogen synthesis fluxes could be strongly decreased when HPI and PGM were simultaneously inhibited in AS-30D cells but not in hepatocytes. Experimental assessment of these predictions showed that both the glycolytic and glycogen synthesis fluxes of AS-30D cells, but not of hepatocytes, were inhibited by oxamate, by inducing increased Fru1,6BP levels, a competitive inhibitor of HPI and PGM. Conclusion HPI and PGM seem suitable targets for decreasing glycolytic and glycogen synthesis fluxes in AS-30D cells but not in hepatocytes. General significance The present study identified new therapeutic targets within glucose central metabolism in the analyzed cancer cells, with no effects on non-cancer cells.

During 2006, laboratory studies were conducted to evaluate the pathogenicity of seven isolates of Pandora neoaphidis (Remaudiere & Hennebert) against the cabbage aphid, Brevicoryne brassicae (L.). Two isolates were obtained from the aphids Rhopalosiphum padi (L.) (TEXRP1), and Myzus persicae (Sulzer) (TEXMP1), infesting broccoli (Brassica napus (L.)) in Texcoco, Mexico; the rest of the isolates were obtained from Rhopalosiphum maidis (Fitch) infesting sorghum (Sorghum bicolor (L.) Moench), in five localities in Tamaulipas, Mexico. The greatest percentages of mortality were caused by isolates RBF, TEXRP1, y RBB, at a rate of 87, 76, y 72%, respectively, 240 hours after the initiation of the treatments. These results show the potential of P. neoaphidis as an agent of biological control against B. brassicae, depending of the place and the origin of the isolate.

Resumen El estudio fue realizado para determinar los parasitoides que atacan al picudo del algodonero, Anthonomus grandis Boheman (Coleoptera:Curculionidae), en la region algodonera del norte de Tamaulipas, Mexico, y presentar una clave taxonomica de facil uso, para su identificacion. Se colectaron botones florales danados por A. grandis durante 1999, 2000, 2001 y 2002, en parcelas de algodonero mantenidas sin aspersiones de insecticidas. De los especimenes emergidos del material colectado, se logro identificar a los ectoparasitoides larvales Bracon mellitor Fabricius (Hymenoptera:Braconidae), Catolaccus grandis (Burks) y C. hunteri Crawford (Hymenoptera:Pteromalidae), Eurytoma sp. (Hymenoptera: Eurytomidae), y Microdontomerus sp. (Hymenoptera:Torymidae), y al endoparasitoide huevo-larva Urosigalphus anthonomi Crawford (Hymenoptera: Braconidae). Estos parasitoides de A. grandis tambien han sido encontrados en otras areas algodoneras de Mexico y los Estados Unidos de America. La clave taxonomica generada p...

Gluconeogenesis is an essential pathway in methanogens because they are unable to use exogenous hexoses as carbon source for cell growth. With the aim of understanding the regulatory mechanisms of central carbon metabolism in Methanosarcina acetivorans, the present study investigated gene expression, the activities and metabolic regulation of key enzymes, metabolite contents and fluxes of gluconeogenesis, as well as glycolysis and glycogen synthesis/degradation pathways. Cells were grown with methanol as a carbon source. Key enzymes were kinetically characterized at physiological pH/temperature. Active consumption of methanol during exponential cell growth correlated with significant methanogenesis, gluconeogenic flux and steady glycogen synthesis. After methanol exhaustion, cells reached the stationary growth phase, which correlated with the rise in glycogen consumption and glycolytic flux, decreased methanogenesis, negligible acetate production and an absence of gluconeogenesis. Elevated activities of carbon monoxide dehydrogenase/acetyl-CoA synthetase complex and pyruvate: ferredoxin oxidoreductase suggested the generation of acetyl-CoA and pyruvate for glycogen synthesis. In the early stationary growth phase, the transcript contents and activities of pyruvate phosphate dikinase, fructose 1,6-bisphosphatase and glycogen synthase decreased, whereas those of glycogen phosphorylase, ADP-phosphofructokinase and pyruvate kinase increased. Therefore, glycogen and gluconeogenic metabolites were synthesized when an external carbon source was provided. Once such a carbon source became depleted, glycolysis and methanogenesis fed by glycogen degradation provided the ATP supply. Weak inhibition of key enzymes by metabolites suggested that the pathways evaluated were mainly transcriptionally regulated. Because glycogen metabolism and glycolysis/gluconeogenesis are not present in all methanogens, the overall data suggest that glycogen storage might represent an environmental advantage for methanosarcinales when carbon sources are scarce. Also, the understanding of the central carbohydrate metabolism in methanosarcinales may help to optimize methane production.

Since 2008, a wasp species has been observed to predate nymphs of Diaphorina citri Kuwayama (Hemiptera: Psyllidae) (Fig. 1), the Asian citrus psyllid, one of the vectors of the bacterial patho gen Candidatus Liberibacter asiaticus, causal agent of the deadly citrus greening disease (Xuet al. 1998; Gamier & Bove 2000). The wasp species was identified as the Mexican honey wasp, Brachygastra mellifica (Say 1837) (Vespidae: Polistinae) by M. Buck. This wasp was first ob served attacking D. citri nymphs in 2008 in sweet orange, Citrus x sinensis (L.) Osbeck (Rutaceae), and lemon, Citrus x limon (L.) Burm. f. (Ruta ceae), groves, planted 3 to 5 yr ago in Rio Bravo, Tamaulipas, Mexico (25°56'39.12"N, 98°07'3.9"W, 28. 2 elev.). We have been observing B. mellifica since 2008 at Rio Bravo, and have found that its predatory activity is greatest during Jul through Sep when a high population of D. citri nymphs is present on new flush. B. mellifica are small ocial wasps (body length 7-9 mm), and are one of the few insect species, other than honey bees, that produce and store honey (Sugden & McAllen 1994). The species con

Presentamos una sinopsis de las 17 especies del género Pristimantis registradas en la Reserva Ecológica Río Zuñag. Esta reserva se ubica en la cuenca alta del río Pastaza, en la Cordillera Oriental de los Andes de Ecuador, entre 1400 y 2200 m de elevación. Incluimos la descripción de una nueva especie de Pristimantis caracterizada por su coloración en vida (dorso amarillo ámbar con marcas café-rojizas, y manchas anaranjadas bordeadas de amarillo en las ingles y en las superficies posteriores de los muslos) y la presencia de dos tubérculos pequeños sobre el párpado superior y un tubérculo interorbital pequeño. Estimamos que dentro del rango altitudinal de la reserva podrían existir 23 especies de Pristimantis, divididos en dos ensamblajes que se dividen aparentemente en la cota de 1800 m de elevación.

At the National Museum of Anthropology and History in Mexico City, in a gallery dedicated to the civilization of western Mexico, a ceramic figure that resembles an insect was found among other figures representing birds and mammals. The figure that resembles an insect is 22 to 25 cm long and 20 to 25 cm tall. It was found inside a “tumba de tiro”, a kind of grave, of the late Preclassic and Early Classic Period at Colima, Mexico (Valdez 1994). The figure is estimated to have been created between 200 B.C. and 600 A.C. The shape of the figure seems to come from an observation in situ, more than the sole imagination of the author. The figure is morphologically similar to an apterous female aphid (Hemiptera: Aphididae) parasitized by a hymenopteran insect. The characteristics of an apterous female aphid (Borror et al. 1989) that are coincident with those in the figure are: absence of wings, pear-shaped body, and cornicles on the back (Fig. 1). The thorax and abdomen are not differentiated, as they are in winged aphids, because both body parts are similar in color and consistency (Pena 1992). When observing the shape and inclination of the figure, the front part appears to be the aphid head with mouthparts at the inferior level, as though in a feeding position. The details of the thorax-abdomen in the figure fit the description of aphids parasitized by hymenopterous Aphelinidae and Aphidiinae (Braconidae), as indicated by Knutson et al. (1993) and Pope and Tollefson (1998). Parasitized aphids acquire a golden color and remain attached to the green vegetal tissue substrate on which they were feeding (Godfray 1994, Saunderland et al. 2005). Antennae are not found on the ceramic figure. The antennae of the aphid model for the ceramic figure might have been overlooked because of lack of a magnifying instrument such as a microscope that was not available until the second half of the 17 Century (Kruif 1982), at least 1,000 years after the figure was created. Antennae also might be lacking from the figure because antennae are lost when the cuticle of a parasitized aphid hardens (Knutson et al. 1992), and appendages are lost because of wind, hand manipulation, or other reasons. ________________________ Colegio de Postgraduados, Montecillo, Texcoco, Edo. de Mexico Campo Experimental General Teran, General Teran, N. L. Paseo de la Reforma and Gandhi Street, Bosque de Chapultepec, D. F.

Modificación al proceso de producción masiva de los parasitoides Catolaccus grandis y Catolaccus hunteri. El presente estudio se realizó con el objetivo de modificar la tecnología de producción masiva de Catolaccus grandis y Catolaccus hunteri, himenópteros parasitoides de Anthonomus grandis el picudo del algodonero en Tamaulipas, México en el 2002. Se determinó la eficiencia del papel toalla para el secado de manos, en el sellamiento de cápsulas moldeadas en cera de hidrocarburos y poliolefina (LCHP), donde se confina al huésped, y evaluar la efectividad del gorgojo del garbanzo Callosobruchus maculatus como hospedante facticio para la cría de ambos parasitoides. Hubo producción masiva de C. grandis y C. hunteri utilizando C. maculatus como huésped y el papel toalla fue efectivo para sellar los orificios de las cápsulas moldeadas en LCHP. La producción masiva de C. grandis y C. hunteri mediante C. maculatus, contribuyó a incrementar la seguridad y facilidad del proceso, además de una significativa reducción de costos. El papel toalla en el sellado de los orificios de las cápsulas moldeadas en LCHP, redujo en un 50% por m² los costos del proceso, sin afectar la eficiencia del parasitismo y emergencia de C. grandis. Modifications to the process of mass production of parasitoids Catolaccus grandis and Catolaccus hunteri. The present study was conducted to modify the actual mass rearing technology for Catolaccus grandis and Catolaccus hunteri, hymenoptera parasitoids of Anthonomus grandis, the cotton boll weevil, in Tamaulipas, México during 2002. The efficiency of the paper towel to seal the wax hydrocarbon polyolefin molded capsules where the host is confined was determined; and the Chickpea weevil Callosobruchus maculatus effectivity was evaluated as a facticious host to rear both parasitoids. The results indicated that C. grandis y C. hunteri mass reared through C. maculatus as a facticious host was possible, and paper towel was effective in sealing the holes in molded WHPS capsules. This mass rearing of C. grandis y C. hunteri by using C. maculatus may contribute to increase security and easiness in the process, and a significant reduction in costs. Paper towel used to seal holes in molded WHPS capsules reduce costs in 50% per square meter of material, without affecting parasitism and emergence of de C. grandis de C. grandis.

SummarySixty-four pre-school-age children from a poor urban population in Colombia were studied to determine the influence of moderate to severe malnutrition on several proteins in the serum and tears. Secretory IgA, lysozyme, and amylase were found in significantly reduced concentrations in the tears of malnourished children. No influence of nutritional status on total proteins, albumin, and aminopeptidase was observed in this secretion. In the serum, IgA concentrations were significantly higher in the most malnourished group, while total proteins and albumin were reduced. These data suggest that increased susceptibility to infections of mucosal surfaces in malnourished children may be due to reduced concentrations of protective substances such as IgA and lysozyme in secretions.

Dermal reactions and IgE levels were compared in 51 asthmatic Colombian children identified on the basis of anthropometric measurements as nutritionally normal (25) or mildly (16) or moderately (10) undernourished. Twenty-five nonatopic children served as controls. Total serum IgE concentrations were significantly elevated in the asthmatic group as a whole. Moderately malnourished (grade 11) asthmatic children had more than twice as much serum IgE as normal or mildly malnourished (grade I) asthmatic subjects and seven times more than nonatopic children. Intestinal parasitism did not appear to contribute to these differences in IgE levels. Serum levels of IgA and IgD were similarly elevated in grade II asthmatics. Concentrations of serum IgG, IgM, and C3 and C4 complement were unaffected by nutritional or allergic status. Eosinophilia in nasal mucus was significantly reduced in grade I and grade II malnourished asthmatic children. Among asthmatics, the most frequent dermal reactions were to mite antigens (96%), house dust (67%), and grass pollens (35%). Significant levels of specific IgE were detected by the RAST to two species of mites in nearly all atopic children. There was no apparent influence of nutritional status on the distribution of reactivity to a particular allergen by either dermal reactivity or specific IgE assay. The clinical significance of hyper immunoglobulin E in atopic, moderately malnourished children remains to be elucidated.

Amylase activities were quantitated in secretions of marginally and severely malnourished Colombian children. In young children with a mean age of 21 months, the relative pancreatic and salivary amylase isozyme activities of urine were significantly changed in marginally malnourished children compared to normal children. There was a relative increase in salivary and decrease in pancreatic amylase activity in the undernourished children and total amylase activity was somewhat decreased. Amylase activity in saliva and tears was significantly lower in these malnourished children. Older children who were more severely malnourished had significantly lower amylase activity in their sera and tears. Thus marginal and severe malnutrition affects the production of amylase by the pancreas and salivary glands of young children distinctly. It significantly suppresses amylase activity in tears, saliva, and serum.

Forty-three Colombian children suffering from either kwashiorkor (21), combined protein-calorie malnutrition (11), or maramus (11) were hospitalized and provided a high protein, high calorie diet for 4 to 5 wk. Improvement in clinical and nutritional status was accompanied by significant increases in levels of serum immunoglobulins G and M and C3 complement and by significant decreases in serum immunoglobulin A concentrations, especially in infants with kwashiorkor. Skin test reactions to purified protein derivative and candidin improved during renutrition. Lymphocyte blastogenesis after stimulation in vitro with phytohemagglutinin and pokeweed mitogen increased rapidly during hospitalization. After 1 yr posttreatment, cell-mediated immune responses, both in vivo and in vitro, had diminished. These results indicate that some aspects of the immune response are affected to a different degree in kwashiorkor, maramus, and combined malnutrition. Short-term nutritional rehabilitation has a differential effect on the long-term restoration of various aspects of immunity.