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BACKGROUND: Despite the uncontrolled distribution of the Influenza A virus through wild birds, the detection of canine influenza virus and equine influenza virus in Mexico was absent until now. Recently, outbreaks of equine and canine influenza have been reported around the world; the virus spreads quickly among animals and there is potential for zoonotic transmission. METHODS: Amplification of the Influenza A virus matrix gene from necropsies, nasal and conjunctival swabs from trash service horses and pets/stray dogs was performed through RT-PCR. The seroprevalence was carried out through Sandwich enzyme-linked immunosorbent assay system using the M1 recombinant protein and polyclonal antibodies anti-M1. RESULTS: The matrix gene was amplified from 13 (19.11%) nasal swabs, two (2.94%) conjunctival swabs and five (7.35%) lung necropsies, giving a total of 20 (29.41%) positive samples in a pet dog population. A total of six (75%) positive samples of equine nasal swab were amplified. Sequence analysis showed 96-99% identity with sequences of Influenza A virus matrix gene present in H1N1, H1N2 and H3N2 subtypes. The phylogenetic analysis of the sequences revealed higher identity with matrix gene sequences detected from zoonotic isolates of subtype H1N1/2009. The detection of anti-M1 antibodies in stray dogs showed a prevalence of 123 (100%) of the sampled population, whereas in horses, 114 (92.68%) positivity was obtained. CONCLUSION: The results unveil the prevalence of Influenza A virus in the population of horses and dogs in the state of Nuevo Leon, which could indicate a possible outbreak of equine and Canine Influenza in Mexico. We suggest that the prevalence of Influenza virus in companion animals be monitored to investigate its epizootic and zoonotic potential, in addition to encouraging the regulation of vaccination in these animal species in order to improve their quality of life.

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The global rise in urbanization and industrial activity has led to the production and incorporation of foreign contaminant molecules into ecosystems, distorting them and impacting human and animal health. Physical, chemical, and biological strategies have been adopted to eliminate these contaminants from water bodies under anthropogenic stress. Biotechnological processes involving microorganisms and enzymes have been used for this purpose; specifically, laccases, which are broad spectrum biocatalysts, have been used to degrade several compounds, such as those that can be found in the effluents from industries and hospitals. Laccases have shown high potential in the biotransformation of diverse pollutants using crude enzyme extracts or free enzymes. However, their application in bioremediation and water treatment at a large scale is limited by the complex composition and high salt concentration and pH values of contaminated media that affect protein stability, recovery and recycling. These issues are also associated with operational problems and the necessity of large-scale production of laccase. Hence, more knowledge on the molecular characteristics of water bodies is required to identify and develop new laccases that can be used under complex conditions and to develop novel strategies and processes to achieve their efficient application in treating contaminated water. Recently, stability, efficiency, separation and reuse issues have been overcome by the immobilization of enzymes and development of novel biocatalytic materials. This review provides recent information on laccases from different sources, their structures and biochemical properties, mechanisms of action, and application in the bioremediation and biotransformation of contaminant molecules in water. Moreover, we discuss a series of improvements that have been attempted for better organic solvent tolerance, thermo-tolerance, and operational stability of laccases, as per process requirements.

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Laccases have attracted a great deal of interest because of their remarkable ability for the degradation of synthetic dyes present in wastewaters. New laccase producing sources with robust operational and functional properties are being continuously explored. In this work, the potential for the decolorization and detoxification of synthetic dyes was evaluated in two Mexican strains of the genus Trametes. The decolorization capacity of Trametesmaxima LE130 and Trametes sp. LA1 was tested in solid and liquid media. The phytotoxicity of the degradation products was determined using Raphanussativus and Pisum sativum seeds. In solid media, both strains showed a higher decolorization capacity (p ≤ 0.05) than Phanerochaetechrysosporium ATCC 24725, which is known to be very efficient in lignin and dye-degradation. They produced laccase as the main ligninolytic enzyme; T. maxima LE130 secreted a single isoform of 43.9 kDa, while Trametes sp. LA1 produced three isoforms of 67.3, 58.6 and 52.7 kDa, respectively. Trametes sp. LA1 culture fluids were capable of decolorizing and detoxifying chemically diverse dyes (anthraquinonic dye Remazol Brilliant Blue R, azoic Reactive Black 5 and triphenylmethane Crystal Violet) without the addition of redox mediators. Therefore, this could be considered as a new laccase source which could be potentially competitive in the bioremediation of dye-containing wastewaters.

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The aim of the research was to determine the impact of fermentation with Pleurotus ostreatus on kidney beans, black beans, and oats. The results indicate that the fungus has a positive effect on the substrates when compared to the controls. The antioxidant activity (39.5% on kidney beans and 225% on oats in relation to the controls) and content of total polyphenols (kidney beans three times higher regarding the controls) increased significantly by the presence of the fungus mycelium, even after simulated digestion. There was a significant increase in protein digestibility (from 39.99 to 48.13% in black beans, 44.06 to 69.01% in kidney beans, and 63.25 to 70.01% in oats) and a decrease of antinutrient tannins (from 65.21 to 22.07 mg in black beans, 35.54 to 23.37 in kidney beans, and 55.67 to 28.11 in oats) as well as an increase in the contents of some essential amino acids. Overall, this fermentation treatment with Pleurotus ostreatus improved the nutritional quality of cereals and legumes, making them potential ingredients for the elaboration and/or fortification of foods for human nutrition.

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RESUMEN La trichinellosis es una enfermedad parasitaria zoonótica y cosmopolita, se debe al consumo de carne deficientemente cocida, principalmente proveniente del cerdo, diversos estudios avalan la eficacia de la administración de inmunoterapia. Se ha caracterizado un antígeno inmunodominante de 45 kDa y se plantea como objetivo evaluar la presencia de anticuerpos IgA, IgM e IgG antti-Trichinella spiralis a lo largo de la infección, así como el comportamiento en la administración de la inmunización de 45 kDa de Trichinella spiralis (T. spiralis) administrado por vía sublingual y vía parenteral. Se utilizaron 36 murinos (Long Evans), seis para la infección y purificación del antígeno de 45 kDa, 30 para formar los grupos de trabajo, control sano (cinco murinos), control infectado (cinco murinos), y 20 para los grupos experimentales, se inmunizaron dos grupos con cuatro dosis (0, 7, 14 y 21 días) del inmunógeno de 45 KDa de T. spiralis, uno por vía sublingual y otro por vía parenteral y se retaron con 500 larvas infectantes (LI) de T. spiralis siete días después de la ultima inmunización y dos grupos más se infectaron con 500 LI y se inmunizaron a las cuatro semanas postinfección por ambas vías. La respuesta se evaluó por inmunofluorescencia indirecta (IFI) por microscopia confocal para determinar la respuesta humoral con anticuerpos de clase IgG, IgM e IgA.

ABSTRACT Trichinellosis is a cosmopolitan zoonotic disease produced mainly by the consumption of poorly cooked swine meat. Several studies have probed the efficiency of immunotherapy as a method for the treatment of trichinellosis. In this work, a 45 kDa immunodominant antigen was characterized, and the presence of IgA, IgM and IgG antti-Trichinella spiralis antibodies was evaluated during the course of the infection. In addition, the differences between sublingual and parenteral administration of the 45 kDa T. spiralis antigen were determined. Long Evans rats were used both to purify the 45 kDa antigen and to evaluate the immune response produced in six different groups: healthy and infected controls; two groups of immunized murines (sublingually and parenterally) with four doses of the 45 kDa T. spiralis immunogen administered at days 0, 7, 14 and 21 and challenged with 500 T. spiralis infective larvae (IL) 7 days after the last immunization; and finally, two groups of murines infected with 500 IL ofT. spiralis, immunized at week 4 post infection by the same two routes. The humoral response was evaluated by indirect immunofluorescence by confocal microscopyin order to determine the presence of IgA, IgM and IgG antibodies.

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Laccase from Pycnoporus sanguineus CS43 was successfully immobilized onto Immobead-150 and Eupergit-C by covalent binding and by entrapment in LentiKats. The highest immobilization was onto Immobead-150 (97.1±1.2%) compared to the other supports, LentiKats (89±1.1%) and Eupergit-C (83.2±1.4%). All three immobilized enzyme systems showed increased thermostability and better mechanical properties than free laccase. Moreover, after 5 cycles of reuse of these systems, 90% of initial laccase activity was retained. Immobead-150 and LentiKats systems exhibited the highest efficiencies in removal of m-cresol under the combined actions of biodegradation and adsorption, while laccase entrapped in LentiKats showed a high ability for degradation of m-cresol within 24h. In addition, the typical Michaelis-Menten enzymatic model effectively described the kinetic profile of m-cresol degradation by the enzyme entrapped in LentiKats. Based on the results obtained in the present study, it can be established that the immobilized biocatalysts developed here possess significant potential for wastewater treatment.

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Rotavirus vaccine was developed using the most prominent G and P genotypes circulating in children population. Therefore, severe gastroenteritis has been reduced around the world. This study investigated the G and P rotavirus genotypes circulating in children from two hospitals in the city of Chihuahua, Mexico. Additionally, polyclonal antibodies against Rotavirus Wa strain were used to determine their homotypic and heterotypic reactivity to both P[8] and P[4] genotypes. G1, G2, and G3 VP7 genotypes and P[8] and P[4] VP4 genotypes were detected in common and uncommon combinations as well as mixed infectious. The predominant combination was G1P[8]. Phylogenetic analysis of VP4 gene revealed the presence of P[8]-1 and P[8]-3 lineages of P[8] genotype and P[4]-5 lineage of P[4] genotype. All but five G1P[8] rotavirus were detected by polyclonal anti-Rotavirus Wa strain. Mutation analysis revealed differences in three of the four neutralizing epitopes previously reported to VP8* subunit of VP4 protein. Results of this study offer insights over genetic variants of field rotavirus that could be detected in a homotypic and heterotypic way by antibodies elicited to rotavirus with P[8] genotype. [Int Microbiol 2016; 19(1):27-32].

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The production of thermostable laccases from a native strain of the white-rot fungus Pycnoporus sanguineus isolated in Mexico was enhanced by testing different media and a combination of inducers including copper sulfate (CuSO4). The best conditions obtained from screening experiments in shaken flasks using tomato juice, CuSO4, and soybean oil were integrated in an experimental design. Enhanced levels of tomato juice as the medium, CuSO4 and soybean oil as inducers (36.8% (v/v), 3 mmol/L, and 1% (v/v), respectively) were determined for 10 L stirred tank bioreactor runs. This combination resulted in laccase titer of 143,000 IU/L (2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid), pH 3.0), which represents the highest activity so far reported for P. sanguineus in a 10-L fermentor. Other interesting media resulting from the screening included glucose-bactopeptone which increased laccase activity up to 20,000 IU/L, whereas the inducers Acid Blue 62 and Reactive Blue 19 enhanced enzyme production in this medium 10 times. Based on a partial characterization, the laccases of this strain are especially promising in terms of thermostability (half-life of 6.1 h at 60 °C) and activity titers.

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Trichomoniasis is one of the most common acute sexually transmitted curable diseases, and it is disseminated worldwide generating more than 170 million cases annually. Trichomonas vaginalis is the parasite that causes trichomoniasis and has the ability to destroy cell monolayers of the vaginal mucosa in vitro. Sphingomyelinases (SMase) are enzymes that catalyze the hydrolysis of sphingomyelin into ceramide and phosphorylcholine. Ceramide appears to be a second messenger lipid in programmed apoptosis, cell differentiation, and cell proliferation. Sphingomyelinase is probably a major source of ceramide in cells. Signal transduction mediated by ceramide leads cells to produce cytokine induced apoptosis during several inflammatory responses. SMase are also relevant toxins in several microorganisms. The main objective of this research is to identify SMase activity of T. vaginalis in the total extract (TE), P30, and S30 subfractions from brooked trophozoites. It was found that these fractions of T. vaginalis have SMase activity, which comes principally from P30 subfraction and was mainly type C. Enzymatic activity of SMase increased linearly with time and is pH dependent with two peaks by pH 5.5 and pH 7.5. The addition of manganese to the reaction mixture increased the SMase activity by 1.97.

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Sphingomyelinase (SMase) activity was measured in Entamoeba histolytica particulate and soluble subcellular fractions. The effects on SMase of incubation time, total protein concentration, pH, and several divalent cations were determined. SMase-C and other unidentified esterase activity were detected in soluble and particulate fractions. SMase-C was 94.5-96.0% higher than the unidentified esterase activity. Soluble and insoluble SMase-C specific activities increased with protein dose and incubation time. Soluble and insoluble SMase-C activities were maximum at pH 7.5 and were dependent on Mg(2+), Mn(2+), or Co(2+), and inhibited by Zn(2+), Hg(2+), Ca(2+), and EDTA. SMase-C was active in the pH range of 3-10 and its maximum activity was at pH 7.5. The soluble and insoluble SMases have remarkably similar physicochemical properties, strongly suggesting that E. histolytica has just one isoform of neutral SMase-C that had not been described before and might be essential for E. histolytica metabolism or virulence.

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We recently reported that DAG (diacylglycerol) generated during sphingomyelin synthesis plays an important role in protein kinase C activation and cell proliferation in Madin-Darby canine kidney cells [Cerbon and Lopez-Sanchez (2003) Biochem. J. 373, 917-924]. In yeast cells, IPC (inositol phosphoceramide) synthase catalyses the transfer of phosphoinositol from phosphatidylinositol to ceramide to form IPC and generates DAG. In the present study, we found that, during the G1 to S transition after N2-starvation, there was a significant increase in the synthesis of IPC accompanied by a progressive increase (up to 6-fold) in the level of DAG. The increased DAG levels coincided with decrements in ceramide and sphingoid base levels, conditions that are adequate for the activation of putative protein kinase C required for the G1 to S transition and proliferation of yeast cells. To separate the role of DAG generated during IPC synthesis from that originating from other sources, we utilized beta-chloroalanine and myriocin, inhibitors of serine:palmitoyl-CoA transferase, the first committed step in sphingolipid synthesis, to avoid accumulation of sphingolipid intermediates. When the synthesis of sphingolipids was inhibited, DAG accumulation was significantly decreased and the G1 to S transition was blocked; such blockage was avoided by metabolic complementation with phytosphingosine. The DAG/ceramide ratio was 0.27 and it changed to 2.0 during growth re-initiation, suggesting that the synthesis of phosphosphingolipids could act to switch growth arrest (increased ceramide) to a mitogenic signal (increased DAG), and that this signalling process is preserved in yeast and mammalian cells.

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