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This study evaluates the production of a biological active surface agent (BASA) through its surface tension (ST) and emulsifying activity (E24) for endosulfan degradation (ED) and Escherichia coli growth inhibition (EcGI) in an agricultural saline soil. The fungus, identified as Penicillium crustosum was isolated from the Citrus sinensis peel (CsP), then the surface properties were evaluated in 9 culture media through a Taguchi L9 experimental design. The culture conditions included: stirring speed, pH, carbon (C) and nitrogen (N) sources; being glucose, NH4N03, 120 rpm and pH of 5, the most significant parameters in the BASA production. The BASA identified as a lipopeptide type, showed a ST = 38 mN m-1 and E24=71%. Both properties were stable at 80 °C, while ST presented stability in the pH range of 2 - 12, and a saline concentration of 200 g L-1; E24 was also stable at a pH between 8-12. Further application of BASA and fungal inoculum to a contaminated agricultural saline soil presented an EcGI of 99.8% on the 8th day, and ED of 92.9 ± 4.7% in 30 days, respectively; being the first report that uses this fungus for pesticide and bacteria elimination from an agricultural saline soil.

Rhizosphere soil samples of three Pinus chiapensis sites were analyzed for their physicochemical properties, soil bacteria isolated and screened in vitro for growth-promoting abilities. Nine isolates that showed promise were identified to five genera Dyella, Luteimonas, Enterobacter, Paraburkholderia and Bacillus based on the sequences of 16S rRNA gene. All the strains were isolated from non-disturbed stands. These bacteria significantly decreased germination time and increased sprout sizes. Indole acetic acid and gibberellin production and phosphate solubilisation were detected. Results indicate that these biochemicals could be essential for P. chiapensis distribution and suggest the possibility that PGPR inoculation on P. chiapensis seeds prior to planting could improve germination and possibly seedling development.

The objective of the research was to improve the productive parameters in Creole chickens through gonadectomy in the Tungurahua Province, Ecuador. A completely randomized design with three treatments and a control was used, the results were subjected to an analysis of variance (ADEVA) for the separation of means and the Tukey test of 5%, the factors under study were: T1 (8), T2(9) and T3 (10), castrated weeks of age, and uncastrated chickens (20 birds / treatment), with a productive period after castration of 12 weeks. Weight gain 12 weeks after castration was higher in chickens operated on at 8 weeks of age, (343.6 g bird / week, p

AIMS This study evaluated the antimicrobial resistance of Salmonella enterica strains from layer poultry farms in central Ecuador isolated during 2017. This geographical area is responsible for around 60% of total domestic egg production, yet, as of 2019, no reports had been published on the phenotypic and genotypic antibiotic resistance patterns of Salmonella in the layer poultry farms of this area. METHODS AND RESULTS Thirty-one isolates from layer poultry farms in central Ecuador obtained during 2017 were evaluated. The resistance profiles exhibited considerable differences in serovar and sample origin, grouping into nine clades by phenotype. S. Infantis strains were of the MDR phenotype in 94·4% of isolates. S. Typhimurium strains were of a reduced antimicrobial resistance phenotype and 50% showed resistance to one antimicrobial compound. One of the S. enterica nontyped strains had an MDR profile to 11 of the 20 antibiotics evaluated (eight groups). And the two remaining S. enterica nontyped strains showed resistance to two and three antibiotics respectively. The ESBL phenotype, which is resistant to clinically notable antibiotics such as ceftriaxone, ampicillin and cefepime, was observed only in S. Infantis (15/18). These strains harbour the emerging blaCTX-M-65 gene, and co-harbour tetA and sul1 resistance genes in four strains. Additional β-lactamase genes, carbapenemase-producing genes (blaIMP, blaVIM , blaOXA48 , blaKPC , blaNDM ) and colistin-mobile resistance gene mcr-1 were not detected. CONCLUSIONS The findings highlight the potential role of layer poultry farm environments in central Ecuador as reservoirs of MDR Salmonella strains. SIGNIFICANCE AND IMPACT OF THE STUDY These results suggest the necessity of reinforcing biosecurity practices to reduce the probability of transmission of MDR Salmonella across the food chain.

Se determino el comportamiento poblacional del pulgon amarillo del sorgo (PAS) Melanaphis sacchari (Zehntner) y enemigos naturales, en tres localidades del estado de Guanajuato, Mexico. Mediante muestreos con red entomologica y trampas con agua jabonosa, en parcelas semi-comerciales de sorgo con diferentes genotipos, en condiciones de riego y de temporal, sin aplicacion de insecticidas. En sorgo con riego, el PAS ocurrio a partir de la etapa de diferenciacion floral a las 749 UC acumuladas a partir de la nacencia, mientras que, en temporal la presencia ocurrio a partir de la quinta hoja verdadera, cerca de las 500 UC acumuladas. Se observaron 12 especies de entomofagos: Hippodamia convergens Guerin-Meneville, la catarina asiatica Harmonia axyridis Pallas, y la catarina cafe Scymnus loewii Mulsant, la avispa Asaphe sp. (Pteromalidae), hiperparasitoide de Aphidius colemani (Dalmen); Diplazon probablemente scutellaris (Cresson) (Ichneumonidae), parasitoide de moscas sirfide Allograpta obliqua (Say), y A. exotica (Wiedemann), primer registro en el Bajio, Mexico; y a Dinocampus (=Perilitus) coccinellae (Braconidae), parasitoide de la catarina anaranjada.

The use of bacteriocins holds great promise in different areas such as health, food, nutrition, veterinary, nanotechnology, among others. Many research groups worldwide continue to advance the knowledge to unravel a novel range of therapeutic agents and food preservatives. This review addresses the advances of bacteriocins and their producer organisms as biocontrol agents for applications in the medical industry and agriculture. Furthermore, the bacteriocin mechanism of action and structural characteristics will be reviewed. Finally, the potential role of bacteriocins to modulate the signaling in host-associated microbial communities will be discussed.

Phytoplankton blooms can cause acute effects on marine ecosystems due either to their production of endogenous toxins or to their enormous biomass leading to major impacts on local economies and public health. Despite years of effort, the causes of these Harmful Algal Blooms are still not fully understood. Our hypothesis is that bacteria that produce photoactive siderophores may provide a bioavailable source of iron for phytoplankton which could in turn stimulate algal growth and support bloom dynamics. Here we correlate iron concentrations, phytoplankton cell counts, bacterial cell abundance, and copy numbers for a photoactive siderophore vibrioferrin biosynthesis gene in water samples taken from 2017 cruises in the Gulf of California, and the Pacific Ocean off the coast of northern Baja California as well as during a multiyear sampling at Scripps Pier in San Diego, CA. We find that bacteria producing the photoactive siderophore vibrioferrin, make up a surprisingly high percentage of total bacteria in Pacific/Gulf of California coastal waters (up to 9%). Vibroferrin's unique properties and the widespread prevalence of its bacterial producers suggest that it may contribute significantly to generating bioavailability of iron via photoredox reactions.

This work makes use of the so-called phenomenological non-structured modelling approach to propose a novel mathematical structure for the description and prediction of the pH effect over an Isopropanol-Butanol-Ethanol (IBE) fermentation system by Clostridium acetobutylicum pIPA3-Cm2, which includes both an in-line approximation of the pH of the culture medium and also novel expressions to reflect its real time effect over the biomass growth and metabolic response in an attempt to generate a base for the development of process intensification strategies for said fermentation system for biofuel production purposes. The proposed model attained a correlation index R2 = 0.9931 and a p-value

The aim of this study was to evaluate application of a crude enzymatic extract from the mixed culture of Trametes maxima (T. maxima) and Paecilomyces carneus (P. carneus) in removal of phe...

Resumen El objetivo de este trabajo fue aislar e identificar levaduras del lactosuero del queso Paipa y evaluar su potencial probiótico (in vitro) para su uso en alimentación animal. Las cepas se aislaron en caldo extracto de levadura-glucosa-cloranfenicol, se purificaron en agar PDA y se caracterizaron molecularmente. Se aislaron 10 cepas dentro de las que se encuentran Candida kefyr, Kluyveromyces marxianus, Pichia fermentans, entre otras. Las levaduras aisladas fueron evaluadas para evidenciar su uso potencial como probióticos en alimentación animal. Se determinó la resistencia a sales biliares (0,05, 0,1, 0,15, 0,20, 0,25 y 0,30%), la estabilidad al pH del estómago (1,5, 2,0, 2,5, 3,0, 3,5 y 4,0) y resistencia al jugo gástrico (pH 1,5, NaCl de 0,2% y pepsina de 0,32%). En la prueba con diferentes concentraciones de sales biliares, las mejores cepas fueron K. marxianus(30_4) y P. fermentans(28_5). En la prueba de pH, el mejor desempeño lo tuvieron P. marxianus (30_4) y Yarrowia lipolytica. Finalmente, en la prueba de jugos gástricos se destacaron C. kefyr . K. marxianus (R_1). Las cepas que presentaron buen desempeño en casi todas las pruebas fueron K. marxianus (30_4) y P. fermentans(28_5), de tal forma que estas levaduras aisladas del lactosuero de queso Paipa tienen potencial en la aplicación como probióticos en la alimentación animal. Abstract The objective of this study was to isolate and identify yeast strains from whey of Paipa cheese, and evaluate in vitro their potential as probiotics potential in animal feed. The yeast strains were isolated using chloramphenicol-glucose- medium, purified on PDA agar and molecularly characterized. A total of 10 yeast strains were isolated from the whey of Paipa cheese, including Candida kefyr, Kluyveromyces marxianus, Pichia fermentans, among others. These strains were further screened for their use as alternative yeast probiotics strains for animal feed. Resistance to bile salts (0.05, 0.1, 0.15, 0.20, 0.25 and 0.30 %), stability at stomach pH (1.5, 2.0, 2.5, 3.0, 3.5 and 4.0) and resistance to gastric juice (pH 1.5, NaCl 0.2 % and pepsin 0.32 %) were evaluated. The isolates of Kluyveromyces marxianus (30_4) y la Pichia fermentans(28_5) had a higher growth at 0,3 % bile salts. In the pH test, the best performance was for P. marxianus and Yarrowia lipolytica. Finally, in the gastric juice test, Candida kefyr and K. marxianus (R_1) strains were the best. K. marxianus (30_4) and P. fermentans (28_5) strains presented good performance in almost all tests, for that reason, these yeasts isolated from Paipa cheese whey have potential for application as probiotics in animal feed.

This chapter contributes with the understanding of alternative redox mechanisms involved in the degradation of organic pollutants by fungi. The increased demand for products and services has led to environmental pollution, thus promoting the development of a wide range of technologies to reduce their impact on ecosystems. Mycoremediation seems to be a promising solution for the removal of a wide range of toxins in the environment by fungi, mainly the strains associated with green coffee beans and the axenic culture of Aspergillus niger for the removal of benzene, methyl tert-butyl ether, and vat blue dye. For all experiments, maximum removal percentages of 60% and 52% were achieved for benzene and MTBE, respectively, while for vat blue dye, a maximum decolorization percentage of 94% was achieved. Although the degradation of pollutants can be carried out enzymatically, the experimental results suggest that reactive species are probably involved in the degradation of pollutants due to the presence of iron in the culture medium and the production of hydrogen peroxide by fungi.

The treatment of patients with bifascicular block (BFB) and syncope in the absence of structural heart disease (SHD) is not well defined. The objective of our study is to compare pacemaker empirical implantation with the use of electrophysiological studies (EPS). This is a prospective cohort study that included 77 patients with unexplained cardiogenic syncope and BFB without structural heart disease between 1997 and 2012. Two groups: 36 patients received empirical pacemakers (Group A) and 41 underwent EPS (Group B) to guide their treatment. The incidence of syncope recurrence and atrioventricular block was lower in group A. Mortality and complication rates were similar between both groups. Multivariate analysis demonstrated a higher number of events (combined endpoint) in group B. Our study shows that treatment according to EPS does not improve the results of a treatment strategy based on empirical pacemaker.

Some microalgae are recognized for producing pigments and other metabolites with biotechnological importance, particularly, Dunaliella salina is a remarkable one. These kind of compounds are used as food and have a great industrial potential. The pigment industry comprises a millionaire market value, being β-carotene one of the most profitable one. In this study we describe the morphology, molecular identification, growth dynamics, proximal composition, nutrients and pigment content of a recently isolated Dunaliella salina strain (SQ) under different salinity/light conditions, in order to highlight its remarkable properties for biotech/biomed industry. D. salina SQ reached the highest densities (1.07-1.25 cell mL -1 x10 6 ) at low salinities (100-500 mM NaCl) under continuous light regimen (24:0 h Light:Dark). Neoxanthin (Neo) and violaxanthin (Viol) were the most abundant pigments when exposed to 500 mM NaCl (18:6 h Light:Dark). Furthermore, this peculiar strain produces other compounds with high industrial value. Perfiles de crecimiento, composicion de nutrientes y analisis de pigmentos de Dunaliella salina cepa San Quintin Algunas microalgas son reconocidas por producir pigmentos y otros metabolitos con importancia biotecnologica, en particular, Dunaliella salina es una de las mas notables. Este tipo de compuestos se usan como alimento y tienen potencial industrial. La industria del pigmento tiene un valor de mercado millonario, siendo el β-caroteno uno de los mas rentables. En este estudio se describe la morfologia, la dinamica de crecimiento, composicion proximal, composicion de nutrientes y contenido de pigmentos de una cepa de Dunaliella salina (SQ) recientemente aislada. La identificacion de la especie se corroboro mediante tecnicas moleculares. Se cultivo a D. salina bajo diferentes condiciones de salinidad y luz, con el objetivo de resaltar sus propiedades para la industria biotecnologica y biomedica. D. salina SQ alcanzo las densidades mas altas (1.07-1.25 celulas mL -1 x10 6 ) a salinidades bajas (NaCl 100 y 500 mM) en un regimen de luz continua. La neoxantina (Neo) y la violaxantina (Viol) fueron los pigmentos mas abundantes en 500 mM NaCl y un ciclo de luz: oscuridad 18: 6 h. Ademas, esta peculiar cepa produce otros compuestos con alto valor industrial.

Background Aberrant glycosylation is a characteristic of tumour cells. The expression of certain glycan structures has been associated with poor prognosis. In cervical carcinoma, changes in the expression levels of some glycogenes have been associated with lymph invasion. Human papillomavirus (HPV) infection is one of the most important factors underlying the development of cervical cancer. The HPV oncoproteins E6 and E7 have been implicated in cervical carcinogenesis and can modify the host gene expression profile. The roles of these oncoproteins in glycosylation changes have not been previously reported. Methods To determine the effect of the E6 and E7 oncoproteins on glycogene expression we partially silenced the E6 and E7 oncogenes in HeLa cells, we performed a microarray expression assay to identify altered glycogenes and quantified the mRNA levels of glycogenes by RT-qPCR. A protein-protein interaction network was constructed to identify potentially altered glycosylation pathways. Results The microarray analysis showed 9 glycogenes that were upregulated and 7 glycogenes that were downregulated in HeLa shE6/E7 cells. Some of these genes participate in glycosylation related to Notch proteins and O-glycans antigens. Conclusions Our results support that E6 and E7 oncoproteins could modify glycogene expression the products of which participate in the synthesis of structures implicated in proliferation, adhesion and apoptosis.

Acetone–butanol–ethanol (ABE) fermentation process can be exploited for the generation of butanol as biofuel, however it does need to overcome its low volumetric solvent productivity before it can commercially compete with fossil fuel technologies. In this regard, mathematical modelling and simulation analysis are tools that can serve as the base for process engineering development of biological systems. In this work, a novel phenomenological kinetic model of Clostridium acetobutylicum ATCC 824 was considered as a benchmark system to evaluate the behaviour of an ABE fermentation under different process configurations using both free and immobilized cells: single stage batch operation, fed-batch, single stage Continuous Stirred Tank Reactor (CSTR) and multistage CSTRs with and without biomass recirculation. The proposed model achieved a linear correlation index r 2 = 0.9952 and r 2 = 0.9710 over experimental data for free and immobilized cells respectively. The predicted maximum butanol concentration and productivity obtained were 13.08 g·L − 1 and 1.9620 g·L − 1 ·h − 1 respectively, which represents an increase of 1.01% and 990% versus the currently developed industrial scale process reported currently into the literature. These results provide a reliable platform for the design and optimization of the ABE fermentation system and showcase the adequate predictive nature of the proposed model.

The aim of this work was to isolate pulp (PH) and seed hydrocolloids (SH) of the fruit of Hymenaea corbaril L. and determinate chemical, functional and rheological properties, as a proposal of a new attractive product for functional applications in food systems. Both hydrocolloids have a high content of carbohydrates, minerals and fiber. The solubility of PH was higher 94.1%. The emulsifying capacity of SH, PH and GG increases with the hydrocolloid concentration. The emulsions showing a good stabilization stability with drop sizes of 5–20 μm. The emulsions PH and SH at 1% were higher stability than guar gum (GG), due to slower down the cremation index after 3 days of storage at 35 and 40°C. The hydrocolloids exhibited a pseudoplastic behavior at concentrations of 0.5–2%. The elastic behavior suggests its application to edible films, while the viscous behavior suggests its incorporation in food systems. Los hidrocoloides son utilizados como aditivos alimentarios, obtenidos de endospermos de semillas de dicotiledóneas. Una interesante alternativa para su uso como fuente biológica del estado de Guerrero es la extracción de hidrocoloides de pulpa (PH) y semilla (SH) del fruto de Hymenaea corbaril L. El objetivo de este trabajo fue aislar hidrocoloides de pulpa y semilla y determinar sus propiedades químicas, funcionales y reológicas para proponerlos como un nuevo producto atractivo con aplicación a los sistemas alimenticios. Los resultados fisicoquímicos mostraron que ambos hidrocoloides poseen un alto contenido en carbohidratos, minerales y fibra. La solubilidad del PH es mayor con 94.1%. Se observó buena estabilización de emulsiones con tamaños de gota de 5- 20 μm. Las emulsiones de PH y SH al 1% mostraron mayor estabilidad que GG debido a que mostraron un descenso más lento en el índice de cremado durante los tres días de almacenamiento a 35 y 40°C. Ambos hidrocoloides muestran comportamientos de tipo pseudoplástico n

México importa el 99 % de la semilla de sorgo Sorghum bicolor. La producción de semillas representa menos del 1 % procedente de genotipos sobresalientes y adaptados. Esto incrementa costos de producción y genera problemas de adaptación de genotipos. La tecnología de producción debe adecuarse a los progenitores específicos y región del país, para incrementar la semilla. Este estudio evaluó la calidad de semillas de catorce líneas de sorgo (progenitoras de siete híbridos), de INIFAP. En el ciclo primavera-verano (P-V) del 2018, en Celaya Guanajuato, México, se establecieron tres fechas de siembra, 12 de mayo, 6 y 28 de junio, bajo un diseño de bloques al azar y tres repeticiones. Se evaluaron los días/floración, el peso de mil semillas, la germinación al momento de la cosecha y después de seis meses de almacenamiento. El análisis de varianza indicó diferencias significativas entre líneas (G), fechas de siembra (FS) en todas las variables y en la interacción G x FS para días a floración; donde las líneas androestériles (líneas A), presentaron diferencia de 8 a 10 días en días a floración con los progenitores masculinos (líneas restauradoras R) en la FS del 6 de junio lo que dificultaría la producción de semilla híbrida. En calidad de semilla a pesar de que se presentaron fuertes precipitaciones durante el llenado de grano y madurez fisiológica las líneas SBA-25, LBA-98, LBA-101 y la cruza SBA25 x SBR-31 sobresalieron por su alto porcentaje (%) de germinación y mantuvieron su calidad después de seis meses de almacenamiento.

Imazapyr and imazamox are frequently applied postemergence to control grass and broadleaf weeds in imidazolinone-resistant sunflower in Argentina. Herbicide carryover to rotational crops represents a disadvantage of these herbicides, particularly in regions with low rainfall during the months prior to rotational crop sowing. Between 2009 and 2012, field and greenhouse studies were conducted on four important sunflower-cropped areas of Argentina. The objective was to quantify the effects of imazapyr alone and imazamox plus imazapyr applied in sunflower crops on the subsequent establishment, growth, and yield of barley, oat, and wheat. In all field experiments, imazapyr alone and imazamox plus imazapyr were applied at recommended rates (80 gha–1and 66 plus 30 gha–1, respectively), and also, in some experiments, at double the recommended rates. Soil bioassays were also conducted in the greenhouse to study the effect of these herbicides on barley, oat, and wheat seedlings. The mixture of imazamox plus imazapyr was safer for rotational crops than imazapyr applied alone, because of the reduced rate of imazapyr in the mixture treatments. Barley was more sensitive to imidazolinones, particularly imazapyr, than the other winter cereals. Imazapyr at double rate (160 gha–1) reduced barley yield by 45% when seeds were sown 165 d after herbicide application and with 240 mm rainfall after herbicide application.

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease that mainly affects women, characterized by the production of autoantibodies. Its causal agent is unknown, but the combination of environmental, hormonal and genetic factors may favor the development of the disease. Parvovirus B19 has been associated with the development of SLE, since it induces the production of anti-single stranded DNA antibodies. It is unknown whether PV-B19 infection is an environmental factor that trigger or reactivate SLE in the Mexican Mayan population.A preliminary serological and molecular study of PV-B19 infection in Mayan women with established SLE was done.IgG and IgM anti PV-B19 were evaluated in 66 SLE patients and 66 control subjects, all women of Mayan origin. Viral DNA and viral load were analyzed by qPCR.Insignificant levels of IgM were observed in 14.3% (4/28) of the patients and 11.4% (4/35) of control subjects. IgG was detected in 82.1% (23/28) of the patients and 82.9% (29/35) of control subjects, but were significantly higher in patients. Viral DNA was found in 86.0% (57/66) of the patients and 81.0% (54/66) of control subjects. Viral load, quantified in 28/66 patients and 31/66 controls which were positive for IgM and IgG, was significantly higher in controls.The high prevalence of PV-B19 in Yucatan, and the presence of IgM, IgG, and viral load in Mayan women with established SLE suggest that PV-B19 infection could be an environmental factor to trigger or reactivate SLE.Lupus eritematoso sistémico (LES) es una enfermedad sistemica autoinmune que afecta principalmente a las mujeres, caracterizada por la producción de autoanticuerpos. El agente causaal es desconocido. Pero la combinación de factores ambientales, hormonales y genéticos podría favorecer el desarrollo de la enfermedad. El parvovirus B19 se asoció con el desarrollo de LES, debido a que induce la producción de anticuerpos anti-cadena simple de DNA. Es desconocido si la infección PV-B19 es un factor ambiental que desencadena o reactiva LES en la población mexicana Maya.Se realizó un estudio serológico y molecular preliminar de la infección de PV-B19 en mujeres Mayas con LES.Se evaluó IgG and IgM anti PV-B19 en 66 pacientes con LES y 66 controles sanos, todas las mujeres fueron de origen Maya. DNAViral y la carga viral fueron analizadas por qPCR.Se determinaron niveles insignificantes de IgM en el 14.3% (4/28) de las pacientes y en el 11.4% (4/35) de los controles. IgG se detectó en el 82.1% (23/28) de los pacients y en el 82.9% (29/35) de los controles. Hubo un alta significancia en los pacientes con LES. DNA viral se encontró en el 86.0% (57/66) de los pacientes y en el 81.0% (54/66) de los controles. La carga viral se cuantifico en 28/66 pacientes y en 31/66 de los controles, la cual fueron positivos para IgM e IgG; fue significativamente mas alta en los controles.La alta prevalencia de PV-B19 en Yucatan y la presencia de IgM, IgG y una carga viral en mujeres Mayas con LES sugiere que la infección con PV-B19 poria ser un factor ambiental que desencadene o reactive el LES.

Pyrroloquinoline quinone (PQQ) is synthesized by only some bacteria, but it has an impact on many organisms, including plant growth-promoting bacteria. This molecule can modify some microbial process such as gene expression, metabolism, among others, which have potential advantageous effects on plants. We describe the conditions and factors that influence the synthesis of PQQ, its functions as an enzymatic cofactor in many reactions, and how it promotes plant growth by phosphate solubilization in soils. We also describe its actions in the synthesis of antimicrobials and its influence on the biocontrol of fungi and bacteria that are pathogenic to plants. PQQ also has a role in the induction of systemic resistance in plants and the molecule may help in the metabolism of other bacteria, promoting a kind of bacterial mutualism. PQQ can also modify gene expression through signal transduction systems and combat stress induced by ultraviolet and gamma radiation, as well as serving as a powerful agent against oxidative stress and perhaps influencing bacterial motility.

Mine tailings are man-made environments characterized by low levels of organic carbon and assimilable nitrogen, as well as moderate concentrations of heavy metals. For the introduction of nitrogen into these environments, a key role is played by ammonia-oligotrophic/diazotrophic heavy metal-resistant guilds. In mine tailings from Zacatecas, Mexico, Serratia liquefaciens was the dominant heterotrophic culturable species isolated in N-free media from bulk mine tailings as well as the rhizosphere, roots, and aerial parts of pioneer plants. S. liquefaciens strains proved to be a meta-population with high intraspecific genetic diversity and a potential to respond to these extreme conditions. The phenotypic and genotypic features of these strains reveal the potential adaptation of S. liquefaciens to oligotrophic and nitrogen-limited mine tailings with high concentrations of heavy metals. These features include ammonia-oligotrophic growth, nitrogen fixation, siderophore and indoleacetic acid production, phosphate solubilization, biofilm formation, moderate tolerance to heavy metals under conditions of diverse nitrogen availability, and the presence of zntA, amtB, and nifH genes. The acetylene reduction assay suggests low nitrogen-fixing activity. The nifH gene was harbored in a plasmid of ∼60 kb and probably was acquired by a horizontal gene transfer event from Klebsiella variicola.

Wild pepper (Capsicum annuum L. var. glabriusculum)is a valuable genetic resource for food and agriculture. The patternsof variation of 12 morphological traits of 17 populations ofwild pepper collected across a latitudinal and climate gradients innorthwestern Mexico were analyzed in a uniform greenhouse experiment.The morphological traits data were axamined by univariateand multivarite analysis. The relationship between phenotypicvariation and latitude of population origen was tested using linearregression analysis. We found high variation within and amongpopulations for most of the measured traits. Populations wereclearly differentiated by univariate analysis of variance and principalcomponent analysis. Because plants grew in a uniform environment,these results indicate that the differences among the populationswere due to genetic differences among them. Plant height,number of fruits, fruit weight, number of seeds per fruit, numberof seeds per plant showed a clinal pattern of variation across latitudinalgradients. Plants from northern populations were shorter,produced more fruits, fruits were heavier, more seeds per fruit andmore seeds per plant than plants from southern populations. Thevariation pattern observed in these traits suggests adaptation to localclimate conditions. The variation of the other traits (stem diameter,leaf length and width, number of branches, fruit length andwidth and seed weight) was not significantly related to latitude deorigin. It is possible that the observed differentiation in these traitswas the result of different regimens of selection (and nonclinal) ineach population, or a consequence of genetic drift.

The goal of this work is to present a class of state observer in order to infer unavailable concentrations in a sulfate-reducing bioreactor containing an anoxic culture of Desulfovibrio alaskensis 6SR from the measurements of the sulfate concentration. The methodology is applied to the corresponding sulfate-reducing model considering modeling uncertainties. The proposed observer design presents a proportional term plus a sigmoid function structure. The model’s observability was locally analyzed by the observability matrix test, concluding that the sulfate-reducing bioreactor is detectable. A sketch of proof of the observer’s convergence is depicted in order to show the asymptotic convergence characteristics. Numerical experiments provide an overview about the superior performance of the proposed observer methodology compared to a sliding-mode and high order sliding mode observers.

In this research, we evaluated the toxic effect of metal ions on mycelial growth and phosphate-solubilising activity of soil-borne micromycetes isolated from the Phragmites australis rhizosphere using Pikovskaya-agar plates supplemented with four metal concentrations. The diameter growth rate (DGR) decreased as the metal concentration rise for all tested fungi. Trichoderma atroviride had the fastest growth rate (1.48 cm2 day−1) and was the least susceptible to Al3+, Cd2+, Cr3+, Cu2+ and Pb2+ with a median effective concentration (MEC50) of 12.19, 0.48, 4.51, 11.44 and 50.05 mM, respectively. Aspergillus japonicus was the most tolerant to Co2+, Ni2+ and Zn2+, with MEC50 values of 3.36, 1.095 and 2.34 mM, respectively. Penicillium italicum was the most tolerant to Cr6+ (MEC50 = 0.677 mM). The ability to solubilise phosphate remained, despite the decrease in the DGR, and P. italicum and Penicillium dipodomyicola had the highest Phosphate Solubilisation Indexes (PSIs) at 1.97 and 2.12, respectively. I...

The aims of this work were to evaluate the phosphate-solubilization and hydrogen peroxide (H2O2) production by the soil-borne micromycetes, Aspergillus japonicus, Penicillium italicum and Penicillium dipodomyicola, isolated from Phragmites australis rhizosphere and to study the effect of several concentrations of Cadmium (Cd(2+)) on both variables. Our results showed that P. italicum achieved a higher P-solubilization and H2O2 production than A. japonicus and P. dipodomyicola, as only P. italicum showed a positive correlation (R(2) = 0.71) between P-solubilization and H2O2 production. In dose-response assays, P. italicum was also more tolerant to Cd(2+) (0.31 mM) in comparison to A. japonicus (0.26 mM). Analysis of the 2(4) factorial experimental design showed that P-solubilization by P. italicum was negatively affected by increases in Cd(2+) (p = 0.04) and yeast extract (p = 0.02) in the culture medium. The production of H2O2 was positively affected only by glucose (p = 0.002). Fungal biomass production was reduced significantly (p = 0.0009) by Cd(2+) and increased (p = 0.0003) by high glucose concentration in the culture medium. The tolerance and correlation between P-solubilization and H2O2 production in the presence of Cd(2+) was strain and species dependent. The effects of Cd(2+), glucose, ammonium sulfate and yeast extract on those variables were evaluated through a two-level factorial design. P. italicum is promising for P-solubilization in soils contaminated with Cd(2+) and may be an alternative for manufacture of biofertilizers to replace chemical fertilizers.

In northern Mexico, the distilled spirit sotol with a denomination of origin is made from species of Dasylirion. The configuration of the volatile metabolites produced during the spontaneous fermentation of Dasylirion sp. must is insufficiently understood. In this study, the aim was to investigate the composition of the microbial consortia, describe the variation of volatile metabolites, and relate such profiles with their particular flavor attributes during the fermentation of sotol (Dasylirion sp.) must. Ascomycota was the phylum of most strains identified with 75% of total abundance. The genus of fermenting yeasts constituted of 101 Pichia strains and 13 Saccharomyces strains. A total of 57 volatile metabolites were identified and grouped into ten classes. The first stage of fermentation was composed of diesel, green, fruity, and cheesy attributes due to butyl 2-methylpropanoate, octan-1-ol, ethyl octanoate, and butanal, respectively, followed by a variation to pungent and sweet descriptors due to 3-methylbutan-1-ol and butyl 2-methylpropanoate. The final stage was described by floral, ethereal-winey, and vinegar attributes related to ethyl ethanimidate, 2-methylpropan-1-ol, and 2-hydroxyacetic acid. Our results improve the knowledge of the variations of volatile metabolites during the fermentation of sotol must and their contribution to its distinctive flavor.

Recent research has shown that in aquatic systems pairs of prokaryote and eukaryote species exercise symbiotic exchanges of metabolites that are essential for the proliferation of either species. Using dinoflagellate Lingulodinium polyedrum cultures and a factorial design, we examined its growth at different concentrations of vitamin B1 (thiamine) and B12 (cobalamin). When both vitamins were at their lowest concentrations tested, 0.033 pM of B1 and 0.053 pM of B12 the growth was limited. When axenic L. polyedrum was co-cultured with the bacterium Dinoroseobacter shibae, a known B1 and B12 producer, then L. polyedrum grew at the same rate as in culture media supplemented with B1 and B12. In the L. polyedrum vitamin—limited culture (V-L), the abundance of attached and free-living D. shibae was higher than in the vitamin—replete (V-R) culture. In the V-R and V-L co-cultures the measured particulate B12 (pB12) concentration of attached and free-living D. shibae were in the range of 4.7 × 10−19 to 3 × 10−18 and 8.4 × 10−21 to1.2 × 10−19 (mol cell−1), respectively. Without B12 or B7 (biotin) added to the culture medium of a co-culture of L. polyedrum and D. shibae, the measured dissolved B12 (dB12) concentration was more than 60 pM higher than necessary for un-limited growth rates of L. polyedrum. In the same culture we measured B7 in the L. polyedrum particulate fraction (pB7; 4.7 × 10−19 to 9.4 × 10−19 mol cell−1). We suggest that in response to the production of B1 and B12 by D. shibae to supply L. polyedrum requeriments, the latter produced B7, which is required by D. shibae, and in our culture was only produced by L. polyedrum when D. shibae was present. We propose that D. shibae can control L. polyedrum through the release of B1 and B12, and L. polyedrum can control D. shibae through the release of B7. D. shibae is also auxotroph for niacin and 4-amino-benzoic acid, not provided by the culture medium. Therefore, L. polyedrum might affect a similar control through the release of these specific compounds and organic substrate necessary for the growth of D. shibae.

Phytoplankton blooms can cause acute effects on marine ecosystems either due to their production of endogenous toxins or due to their enormous biomass leading to major impacts on local economies and public health. Despite years of effort, the causes of harmful algal blooms (HAB) are still not fully understood. Our hypothesis is that bacteria that produce photoactive siderophores may provide a bioavailable form of iron to commensally associated phytoplankton, which could in turn affect algal growth and bloom dynamics. Here we report a laboratory-based study of binary cultures of the dinoflagellate Lingulodinium polyedrum, a major HAB species, with Marinobacter algicola DG893, a phytoplankton-associated bacterium that produces the photoactive siderophore vibrioferrin. Comparing binary cultures of L. polyedrum with both the wild type and the vibrioferrin minus mutant of M. algicola shows that bacteria are necessary to promote dinoflagellate growth and that this growth promotion effect is at least partially related to the ability of the bacterium to supply bioavailable iron via the siderophore vibrioferrin. These results support the notion of a carbon for iron mutualism in some bacterial-algal interactions.

The iron uptake and storage systems of terrestrial/higher plants are now reasonably well understood with two basic strategies being distinguished: Strategy I involves the induction of an Fe(III)-chelate reductase (ferrireductase) along with Fe(II) or Fe(III) transporter proteins while strategy II plants have evolved sophisticated systems based on high-affinity, iron specific, binding compounds called phytosiderophores. In contrast, there is little knowledge about the corresponding systems in marine, plant-like lineages. Herein we report a study of the iron uptake and storage mechanisms in the harmful algal bloom dinoflagellate Lingulodinium polyedrum. L. polyedrum is an armored dinoflagellate with a mixotrophic lifestyle and one of the most common bloom species on Southern California coast widely noted for its bioluminescent properties and as a producer of yessotoxins. Short term radio-iron uptake studies indicate that iron is taken up by L. polyedrum in a time dependent manner consistent with an active transport process. Based on inhibitor and other studies it appears that a reductive-oxidative pathway such as that found in yeast and the green alga Chlamydomonas reinhardtii is likely. Of the various iron sources tested vibrioferrin, a photoactive and relatively weak siderophore produced by potentially mutualistic Marinobacter bacterial species, was the most efficient. Other more stable and non-photoactive siderophores such as ferrioxamine E were ineffective. Several pieces of data including long term exposure to 57Fe using Mossbauer spectroscopy suggest that L. polyedrum does not possess an iron storage system but rather presumably relies on an efficient iron uptake system, perhaps mediated by mutualistic interactions with bacteria.

The goal of this work is to present a closed-loop operational strategy in order to improve the butanol production in an anaerobic continuous bioreactor for the called Acetone-Butanol-Ethanol (ABE) process. The proposed control scheme considers a class of feedback signal which includes a nonlinear bounded function of the regulation error. The control scheme is applied to a phenomenological unstructured kinetic model obtained from an experimental and metabolic study of butanol production by Clostridium acetobutylicum, which allows the proposed structure to predict several operational conditions from batch and continuous regimes. Numerical experiments using the proposed model considering continuous operation were performed in order to find a feasible operating region for maximum butanol production at open-loop regime. The proposed methodology is applied to regulate the product concentration, manipulating the dilution rate to lead to a higher butanol productivity. The closed-loop behaviour of the bioreactor is analysed, finding that the proposed controller minimizes the response time of the system and allows it to achieve a productivity gain of 55 % over open-loop operation. Further numerical experiments show the satisfactory closed-loop performance of the proposed methodology in comparison with a PI controller.

The populations of wild chili pepper (Capsicum annuum var. glabriusculum) are a genetic valuable resource and the knowledge of the germinative ability, is of great importance for its management and conservation. The effects of the temperature on germination of wild chili grown in two environment of light, and the relation with the weight of 100 seeds of five populations of wild chili of the Northwest of Mexico, were recorded. The mother plants grown in greenhouse conditions with 50 and 100 % of solar light. The treatments applied in the germination cameras matched: Fluctuating temperature (25-35 ºC) and constant temperature (25 ºC). The treatment variables were the following: percentage of final germination and mean germination time (T50). These variables performed a greatest treatment response of fluctuating temperature. A widely variation among 50 and 100 % of light was recorded with natural conditions. These temperature fluctuations are determinant in germinative processes. The temperature performed a significantly response in terms of the effect in germination velocity (T50) but not in germination percentage. The final germination was not significantly correlated with the seed weight due to maternal effects. In addition, plants grown in greenhouse conditions, differentiate among populations with a genetic basis.

Eukaryotic phytoplankton and bacteria form complex trophic interactions in nature and cultures. The interaction will depend on the spatial arrangement but the architecture of these arrangements has been little investigated. Here we modified a protocol to identify and localize multiple bacterial taxa attached to phytoplankton cells in culture and natural samples, including sensitive dinoflagellates. Samples were embedded in agarose and hybridized simultaneously with different probes of distinct fluorescence properties. Embedding avoided losses or damage of host cells and preserved the attached bacteria during hybridization and washing. Embedding still allowed efficient hybridization and identification of intact host cells. After fluorescence in situ hybridization of the bacteria the phytoplankton host cells, including dinoflagellates were still intact. Digital image stacks taken with a wide field epifluorescence microscope using different excitation–emission wavelength combinations allow the location of the different bacterial groups on the host cell surface and the spatial relationship of the different bacterial groups.

The main issue of this work is related with the design of a class of nonlinear observer in order to synchronize chaotic dynamical systems in a master-slave scheme, considering different initial conditions. The oscillator of Chen is proposed as a benchmark model and a bounded-type observer is proposed to reach synchronicity between both two chaotic systems. The proposed observer contains a proportional and sigmoid form of a bounded function of the synchronization error in order to provide asymptotic synchronization with a satisfactory performance. Some numerical simulations were carrying out in order to show the operation of the proposed methodology, with possible applications to secure data communications issues.

During 2004 to 2008, weed surveys were conducted in 373 wheat fields of two different cropped areas (southwest [SW] and southeast [SE]) of the southern region of Buenos Aires Province of Argentina where different weed communities were expected because of changes in cropping practices over time, including tillage, crop sequence, fertilizers, and herbicides applied. Weed communities differed between regions, with greater numbers of native species for the SW. Weed community diversity was also greater for the SW region, probably due to the more diverse land use that resulted in greater landscape heterogeneity. Rush skeletonweed, sand rocket, yellow starthistle and turnipseed occurred at higher constancy (proportion of fields in which a given species is present) in the SW region, whereas common chickweed, false bishop's weed, corn speedwell, and common lambsquarters were present more frequently in the SE region. Compared with the 1982 survey, constancy of weeds increased, but those species with high constancy in 1982 were also with high constancy in the recent surveys. Diversity (species richness) was greater in conventional than in a no-tillage system. The constancy of Italian ryegrass, sand rocket, and yellow starthistle was lower under no-till than conventional tillage. Surveys allow identification of changes in weed community related to different agricultural systems. Rotation of crops and livestock avoid the homogenization of the environment at the landscape level. Management strategies will be necessary to prevent the increase of weeds populations' size, preserving plant diversity and the properties of the agroecosystem. Fil: Scursoni, Julio Alejandro. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal; Argentina Fil: Gigón, Ramón. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Bordenave; Argentina Fil: Martin, Andrés Nelson. Universidad de Buenos Aires. Facultad de Agronomía. Departamento de Producción Vegetal; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Vigna, Mario Raul. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Bordenave; Argentina Fil: Leguizamon, Eduardo Sixto. Universidad Nacional de Rosario. Facultad de Ciencias Agrarias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Istilart, Carolina María. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Barrow; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Lopez, Ricardo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Buenos Aires Sur. Estación Experimental Agropecuaria Bordenave; Argentina

Background: Given the considerable role played by Salmonella in the incidence of food contamination, around the world, surveillance of this infection is prioritized by both food producers and health care authorities. Data remains insufficient concerning the prevalence of Salmonella in poultry systems in Ecuador and in Latin America in general. Methods: In this study, we evaluated the presence and diversity of Salmonella serovars in samples taken from 21 layer farms and backyard layers in central Ecuador during August-November 2017. Salmonella was isolated following standardized methods (ISO 6579) and the serovar determination was carried out by PCR. Results: A significant presence of Salmonella was detected in the 21 farms evaluated, with a frequency of 76% (95% confidence interval (CI): 53-92) in environmental surfaces, 33% (95%CI: 15-57) in pooled cloacal swabs from layer hens, 33% (95% CI: 13–59) on feed samples, and 10% (95%CI: 1-30) in backyard layer feces from traditional local markets. The dominant serovars detected were S. Infantis and S. Typhimurium. Conclusions: This study forms a basis for further surveillance of Salmonella serovars in layer farms in central Ecuador.

Locusts, large gregarious and migratory grasshoppers, are pests of economic importance in several regions of the world because of the severe damage they can cause to crops. The Central American locust, Schistocerca piceifrons is the most important locust species in the Americas, and it is distributed in zones of Mexico, Central and South America. In Mexico, despite the efforts to survey and monitor S. piceifrons (Walker) populations, outbreaks are still difficult to predict and prevent, and high economic and ecological costs are incurred in controlling them. The purpose of this study was to build a dynamic model of locust growth and development as a function of environmental conditions in order to identify suitable conditions for the high reproduction rates of this insect. This information can be used to assist in locust management. A modular approach and numerical integration techniques were applied in model building. The main inputs of the model were daily rainfall and temperature data, and phy...

Helicobacter pylori infects more than half of the world’s population, making it the most widespread infection of bacteria. It has high genetic diversity and has been considered as one of the most variable bacterial species. In the present study, a PCR-based method was used to detect the presence and the relative frequency of homologous recombination between repeat sequences (>500 bp) in H. pylori 26695. All the recombinant structures have been confirmed by sequencing. The inversion generated between inverted repeats showed distinct features from the recombination for duplication or deletion between direct repeats. Meanwhile, we gave the mathematic reasoning of a general formula for the calculation of relative recombination frequency and indicated the conditions for its application. This formula could be extensively applied to detect the frequency of homologous recombination, site-specific recombination, and other types of predictable recombination. Our results should be helpful for better understanding the genome evolution and adaptation of bacteria.

The objective was to evaluate the reproductive performance and productivity of Pelibuey ewes in two flocks in Southeastern Mexico. Animals grazed on irrigated star grass (Cynodon plectostachyus). In flock 1, lambs grazed with their mothers from 7 to 70 days of age (weaning age), whereas in flock 2, they were confined and offered chopped grass, a commercial concentrated and managed under restricted suckling until weaning at 60 days of age.. The statistical model included the fixed effects of flock, year and season of lambing, parity number, litter size at weaning, first order interactions and the random effects of ewe and the error term. The means ± SD for age at first lambing, prolificacy, lambing interval (LI), weaning weight, and productivity were 477 ± 85.5 days, 1.41 ± 0.51 lambs, 255.9 ± 51.8 days, 16.5 ± 4 kg, and 18.1 ± 4.42 kg of lamb weaned, respectively. Repeatability estimates for the latter four traits were 0.09, 0.07, 0.11, and 0.13, respectively. All main effects in the models were significant (P

Huanglongbing (HLB), the citrus disease associated with the bacteria ‘Candidatus Liberibacter asiaticus’, is the most important threat of the Mexican citrus industry. Since 2009, this bacterium has been detected in 11 out of 23 citrus producing states of the country, although with a limited distribution in each state. The Asian citrus psyllid (Diaphorina citri Kuwayama [Hemiptera: Psyllidae]) is the vector of this bacterium; the insect is distributed in all the citrus growing zones of Mexico. Presently, the lime production zone in the Mexican states of Colima, Jalisco, Michoacan, Nayarit, and Sinaloa, near to the Pacific Ocean coast, is the most affected by this disease. One of the main strategies to retard or stop the advance of HLB consists in the regional management of the psyllid populations. In order to contribute to the support of this strategy we analyzed the daily courses of temperature and rainfall all over the country to classify the citrus zones according to the probability of occurren...

Pineapple is the second most important tropical fruit in international trade and Mexico ranks ninth in world production. Pink disease is asymptomatic in the field and is characterized by the production of dark discoloration (amber-reddish brown) and its initial effects are not recognized until the fruits are cored and canned. Hence pink disease is considered a major problem in the pineapple canning industry. Four hundred and eighty isolates of pineapple were tested for antagonistic activity vs. Tatumella , causal agent of pink disease, and strain UAPS07070 was selected for further assays. Population dynamics were explored in co-inoculation in vitro and in planta with strain UAPS07070 and T. ptyseos UAPS07007. The population of UAPS07007, the producer strain of the disease severely declined in comparison with the controls. This work contributes to the knowledge of the ecology of pink disease in pineapple, as well as to the comprehension of the interactions between microorganisms colonizing the habitat of the plant.

In this study we established the B1 and B12 vitamin requirement of the dinoflagellate Lingulodinium polyedrum and the vitamin supply by its associated bacterial community. In previous field studies the B1 and B12 demand of this species was suggested but not experimentally verified. When the axenic vitamin un-supplemented culture (B-ns) of L. polyedrum was inoculated with a coastal bacterial community, the dinoflagellate’s vitamin growth limitation was overcome, reaching the same growth rates as the culture growing in vitamin B1B7B12-supplemented (B-s) medium. Measured B12 concentrations in the B-s and B-ns cultures were both higher than typical coastal concentrations and B12 in the B-s culture was higher than in the B-ns culture. In both B-s and B-ns cultures, the probability of dinoflagellate cells having bacteria attached to the cell surface was similar and in both cultures an average of six bacteria were attached to each dinoflagellate cell. In the B-ns culture the free bacterial community showed significantly higher cell abundance suggesting that unattached bacteria supplied the vitamins. The fluorescence in situ hybridization (FISH) protocol allowed the quantification and identification of three bacterial groups in the same samples of the free and attached epibiotic bacteria for both treatments. The relative composition of these groups was not significantly different and was dominated by Alphaproteobacteria (>89%). To complement the FISH counts, 16S rDNA sequencing targeting the V3–V4 regions was performed using Illumina-MiSeq technology. For both vitamin amendments, the dominant group found was Alphaproteobacteria similar to FISH, but the percentage of Alphaproteobacteria varied between 50 and 95%. Alphaproteobacteria were mainly represented by Marivita sp., a member of the Roseobacter clade, followed by the Gammaproteobacterium Marinobacter flavimaris. Our results show that L. polyedrum is a B1 and B12 auxotroph, and acquire both vitamins from the associated bacterial community in sufficient quantity to sustain the maximum growth rate.

The aims of this experiment were to evaluate the addition of coconut water in natura to the freezing media, compare the effect of deionized water vs filtered water of coconut over the post-thaw seminal characteristics, and evaluate the effect of the deionized water and in natura coconut water on the seminal characteristics of boar sperm at different post-thaw times. Thirty-four ejaculates were used divided in three aliquots which received one of the following treatments (T): T1, LEY (bidistilled water, lactose, and egg yolk) and LEYGO (LEY + glycerol and Orvus ET paste); T2, LEY(A) (coconut deionized water, lactose, and egg yolk)-LEYGO(A); and T3, LEY(B) (in natura coconut water, lactose, and egg yolk)-LEYGO(B). Samples of boar semen were frozen according to the Westendorf method, thawed at 38°C, and evaluated at three incubation times (0, 30, and 60 min). Seminal characteristics assessed were motility (Mot), acrosomal integrity (AInt), membrane integrity (MInt), and mitochondrial activity (MAct). T1 showed a higher percentage of viable sperm than T3 (Mot 36.5 vs 5.4 %, AInt 61.8 vs 41.2 %, MInt 50.4 vs 41.3 %, and MAct 56.9 vs 50.5 %). T2 kept a higher percentage of viable sperm at all incubation times. In natura coconut water showed a detrimental effect over the viability of the frozen-thawed boar semen. Deionized coconut water improved the boar semen viability post-thaw, outperforming results of in natura coconut water.

Background: Rabies virus infection causes encephalitis, which is almost always fatal. Vaccination can be extremely effective at preventing disease but is prohibitively costly. Vaccine formulations allowing dose-sparing and fewer inoculations with faster antibody response would be extremely desirable. IMT504, an immunostimulatory non-CpG oligodeoxynucleotide, is a highly potent vaccine adjuvant. Methods: Human and rat antibody measurements, and rat challenge studies were performed. Results: In rats, highly effective immune responses with IMT504 were observed even after diluting vaccine up to 1/625. In highly lethal, live intracerebral rabies challenge studies, protection occurred even with extremely dilute vaccine plus IMT504. In humans, antibody titers developed faster and were significantly higher with IMT504-adjuvanted diluted vaccine vs non-adjuvanted vaccine (full strength or diluted). All five administered IMT504- adjuvanted diluted vaccine reached protective antibodies (≥0.5 IU/ml) after the second injection. After the third injection, individuals receiving IMT504-adjuvanted diluted vaccine reached levels approximately 10 times higher than controls (M ± SEM: 31.0 ± 10.9 vs 3.40 ± 0.99 IU/ml). Conclusions: These data suggest that IMT504 may allow fewer inoculations, highly significant dose-sparing of vaccine, rapid antibody production and protection from rabies. Extensive clinical studies are necessary to confirm if the use of IMT504 will permit significantly greater access to highly effective life-saving rabies vaccines. Fil: Montaner, Alejandro Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología "Dr. César Milstein". Fundación Pablo Cassará. Instituto de Ciencia y Tecnología ; Argentina Fil: de Nichilo, Analía Verónica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología "Dr. César Milstein". Fundación Pablo Cassará. Instituto de Ciencia y Tecnología ; Argentina Fil: Rodriguez, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología "Dr. César Milstein". Fundación Pablo Cassará. Instituto de Ciencia y Tecnología ; Argentina Fil: Hernando Insua, Andres. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología "Dr. César Milstein". Fundación Pablo Cassará. Instituto de Ciencia y Tecnología ; Argentina Fil: Fló, Juan. Immunotech S.a.; Argentina Fil: Lopez, Ricardo A.. Immunotech S.a.; Argentina Fil: Sierra, Verónica. Instituto San Jorge Bagó; Argentina Fil: PAOLAZZI, Claudio Carlos. Instituto San Jorge Bagó; Argentina Fil: Larghi, Oscar. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología "Dr. César Milstein". Fundación Pablo Cassará. Instituto de Ciencia y Tecnología ; Argentina Fil: Horn, David L.. David Horn; Estados Unidos Fil: Zorzopulos, Jorge. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Immunotech S.a.; Argentina Fil: Elias, Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología "Dr. César Milstein". Fundación Pablo Cassará. Instituto de Ciencia y Tecnología ; Argentina

Se trata de un estudio epidemiológico con el objetivo de de establecer la prevalencia del distrés psicológico y su asociación con el consumo de drogas y alcohol, es decir la comorbilidad, en pacientes atendidos en los dos centros principales en la ciudad de Asunción para el tratamiento de esta afección relacionada con la atención en salud mental. Al método fue la de aplicar un cuestionario auto-aplicado y en algunos casos de analfabetos fue realizada una entrevista, el cuestionario estaba basado en la escala K-10 de distrés psicológico y el APGAR familiar. Los resultados muestran que 149 personas que están en tratamiento por cuadros de adicción en estos centros participaron del estudio, siendo el 88,6% hombres, de los cuales el 21% tenían diagnósticos previos como la ansiedad y un 17.4% sufrían de depresión. En tanto que hubo un diagnóstico actual de depresión y ansiedad en 17.4% y 24.2%, respectivamente. El K-10 mostró que 17.5% tenían niveles severos de distrés y 9.4% muy severos de distrés. Se concluye que los niveles encontrados de afectación de distrés psicológico, son muy similares a los encontrados en los diversos estudios internacionales consultados. This is an epidemiological study, aimed to establish the prevalence of psychological distress and its association with drug and alcohol comorbidity, in patients treated at two centers in the city of Asunción - Paraguay for the treatment of this condition associated with mental health care. As for the method used to collect data on these treatment centers was to apply a self-applied and in some cases an interview was conducted in illiterate, the questionnaire was based on K-10 scale of psychological distress and the family APGAR. The results show that 149 people in treatment for addiction in these schools participated in the study, 88.6% being men, of whom 21% had previous diagnoses such as anxiety and 17.4% suffered from depression. While there was a current diagnosis of depression and anxiety in 17.4% and 24.2% respectively. The K-10 showed that 17.5% had severe levels of distress and 9.4% very severe distress. It is concluded that the levels found of involvement of psychological distress, are very similar to those found in international studies consulted. Este é um estudo epidemiológico, a fim de estabelecer a prevalência de sofrimento psíquico e sua associação com drogas e álcool, ou seja, comorbidade, em pacientes atendidos em dois centros principais da cidade de Assunção para o tratamento desta condição relacionada à saúde mental. O método consistiu em um questinário autoaplicável e, em alguns casos, foi realizada uma entrevista, com analfabetas. O questionário foi baseado em K-10 escala de sofrimento psíquico e APGAR famíliar. Os resultados mostram que 149 pessoas em tratamento para dependência nestes centros participaram do estudo, sendo 88,6% homens, dos quais 21% tiveram diagnosticos anteriores, tais como ansiedade, e 17,4% sofreram de depressão, embora tenha havido um diagnóstico atual de depressão e ansiedade em 17,4% e 24,2%, respectivamente. O K-10 mostrou que 17,5% tinham níveis severos de angústia e 9,4%, angústia muito grave. Conclui-se que os níveis encontrados de envolvimento de sofrimento psíquico, são muito semelhantes aos encontrados em estudos internacionais consultados.

Synthetic oligodeoxynucleotides (ODNs) are currently being evaluated as vaccine adjuvants for inducing protective immunity. As maternal vaccination is becoming increasingly common, the potential risk of vaccine formulation using ODN adjuvants should be warranted. A recent study performed in mice suggests that exposure to CpG motifs during pregnancy could result (although at very high doses as compared to the ones proposed for human vaccination) in fetal loss and morphological defects. PyNTTTTGT ODNs are immunostimulatory ODNs not bearing CpG motifs, which are very efficient vaccine adjuvants. In this report, we analyzed the potential teratogenic effect of its prototype IMT504 in rats. This animal model was chosen because PyNTTTTGT ODNs are barely active in mice. Intraperitoneal injection of IMT504 at a dose of 20 mg/kg (more than 1000 times higher than the one proposed for a vaccine dose in humans) at day 6 of pregnancy did not produce a significant decrease in the mean number of implanted fetuses or in the number of live pups delivered. Neither the fetuses nor the offspring presented malformations. Fil: Hernando Insúa, Andrés. Immunotech; Argentina Fil: Rodriguez, Juan M.. Immunotech; Argentina Fil: Elías, Fernanda. Immunotech; Argentina Fil: Fló, Juan. Immunotech; Argentina Fil: López, Ricardo. Immunotech; Argentina Fil: Franco, Raul. Immunotech; Argentina Fil: Lago, Nestor. Gema Biotech; Argentina Fil: Zorzopulos, Jorge. Immunotech; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Montaner, Alejandro Daniel. Immunotech; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Ciencia y Tecnología "Dr. César Milstein". Fundación Pablo Cassará. Instituto de Ciencia y Tecnología ; Argentina

The effect of oxidative stress on indole alkaloids accumulation by cell suspensions and root cultures of Uncaria tomentosa in bioreactors was investigated. Hydrogen peroxide (H 2 O 2 , 200 μM) added to U. tomentosa cell suspension cultures in shaken flasks induced the production of monoterpenoid oxindole alkaloids (MOA) up to 40.0 μg/L. In a stirred tank bioreactor, MOA were enhanced by exogenous H 2 O 2 (200 μM) from no detection up to 59.3 μg/L. Root cultures grew linearly in shaken flasks with a μ = 0.045 days -1 and maximum biomass of 12.08 ± 1.24 g DW/L (at day 30). Roots accumulated 3α-dihydrocadambine (DHC) 2354.3±244.8 μg/g DW (at day 40) and MOA 348.2±32.1 μg/g DW (at day 18). Exogenous addition of H 2 O 2 had a differential effect on DHC and MOA production in shaken flasks. At 200 μM H 2 O 2 , MOA were enhanced by 56% and DHC by 30%; while addition of 800 and 1000 μM H 2 O 2 , reduced by 30-40% DHC accumulation without change in MOA. Root cultures in the airlift reactor produced extracellular H 2 O 2 with a characteristic biphasic profile after changing aeration. Maximum MOA was 9.06 mg/L at day 60 while at this time roots reached ca. 1 mg/L of DHC. Intracellular H 2 O 2 in root cultures growing in the bioreactor was 0.87 μmol/g DW compared to 0.26 μmol/g DW of shaken flasks cultures. These results were in agreement with a higher activity of the antioxidant enzymes superoxide dismutase and peroxidase by 6- and 2-times, respectively. U. tomentosa roots growing in the airlift bioreactor were exposed to an oxidative stress and their antioxidant system was active allowing them to produce oxindole alkaloids.

Polychaetes are a key group in marine benthic communities worldwide because they are ubiquitous and generally abundant and diversified at all depths. Their anatomical complexity, however, makes it very difficult and time consuming to identify them correctly to species level, increasing the costs of any study involving them. Thus, the use of higher taxonomic levels in this group is a useful tool in monitoring or pollution-related studies. In this study, we compared the results obtained at both the species and family levels to assess the faunal changes associated to the different environmental conditions in the southern Gulf of Mexico, a large region known for its ecological and economic importance. We collected and identified 5686 polychaetes from 44 families, 95 genera and 206 species at 68 stations. Their relative density varied from 0% to 29.3% (ind. l−1) being higher in the Campeche Bank. The family richness (1–17) and specific richness (1–46) were both higher in the Campeche Bank. The same pattern was found for diversity and evenness at both taxonomic levels analyzed. The absolute diversity values were different using different taxonomic levels, but increased or decreased similarly at both levels. With the non-metric multidimensional scaling analysis, two main groups of stations emerged: Campeche Bank and Campeche Sound, with two less defined groups indicating a transitional sedimentary zone between them. All the groups were consistent both at family and species level, indicating little loss of information when the family level is used instead of the species level. We conclude that, if good previous basic knowledge of that fauna exists, the family level can be used to monitor environmental and pollution effects in these types of bottoms.