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The development of anthropic activities during recent years has led to an increase in nutrient fluxes in the Río Grande de Comitán and Montebello Lakes National Park, Mexico. In turn, this has modified the dynamics of the biotic community, specifically favoring the presence of cyanobacteria tolerant to contamination. The continual and massive presence of Planktothrix species (spp.) in the system suggests a potential detrimental impact for economic issues and human health. In this study, we identify the morphological and molecular characteristics of Planktothrix populations from seven tropical (1,380-1,740 masl, 23.0-25.5°C) and calcareous lakes and two ponds from a water treatment plant. We also assess the ecological drivers that could be related to the presence of cyanotoxins in the system. The ecological preferences, morphology, 16S rRNA structure, and 16S-23S rRNA internal transcribed spacer found evidence for three species: P. agardhii distributed in neutral to slightly basic water (pH = 7.7-8.7), and P. spiroides and Planktothrix sp. in alkaline waters (pH = 9.1). The presence of the mcyE gene and its validation by liquid chromatography confirmed the presence of two microcystin variants (MC-RR and MC-LR) in at least three populations of P. agardhii. These microcystins put the health of the ecosystem and its inhabitants at risk, a condition that should be addressed and resolved with a water management and detoxification strategy in the basin.

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Food gels are viscoelastic substances used in various gelled products manufactured around the world. Polysaccharides are the most common food gelling agents. The aim of this work was the production and characterization of a gel produced in a blue corn flour fermentation process, where different proportions were used of blue corn (Zea mays L.) flour and Czapek Dox culture medium (90 mL of culture medium with 10 g of blue corn flour, 80 mL of culture medium with 20 g of blue corn flour, and 70 mL of culture medium with 30 g of blue corn flour) and were fermented for three different durations (20, 25, and 30 days) with the Colletotrichum gloeosporioides fungus. A characterization of the gel was carried out studying the rheological properties, proximal analysis, toxicological analysis, microscopic structure, and molecular characterization, in addition to a solubility test with three different organic solvents (ethanol, hexane, and ethyl acetate, in addition to water). The results obtained showed in the rheological analysis that the gel could have resistance to high temperatures and a reversible behavior. The gel is soluble in polar solvents (ethanol and water). The main chemical components of the gel are carbohydrates, especially polysaccharides, and it was confirmed by FT-IR spectroscopy that the gel may be composed of pectin.

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Avian metapneumovirus (aMPV) causes a highly contagious upper respiratory and reproductive disease in chickens, turkeys, and ducks. Here, complete genome sequences of aMPV-B vaccine strains BR/1890/E1/19 (PL21, Nemovac; Boehringer Ingelheim Animal Health, Brazil) and BR/1891/E2/19 (1062; Hipraviar, France) were sequenced and compared with the pathogenic field strain VCO3/60616.

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Avian metapneumoviruses (aMPV subtypes A-D) are respiratory and reproductive pathogens of poultry. Since aMPV-A was initially reported in Mexico in 2014, there have been no additional reports of its detection in the country. Using nontargeted next-generation sequencing (NGS) of FTA card-spotted respiratory samples from commercial chickens in Mexico, seven full genome sequences of aMPV-A (lengths of 13,288-13,381 nucleotides) were de novo assembled. Additionally, complete coding sequences of genes N (n = 2), P and M (n = 7 each), F and L (n = 1 each), M2 (n = 6), SH (n = 5) and G (n = 2) were reference-based assembled from another seven samples. The Mexican isolates phylogenetically group with, but in a distinct clade separate from, other aMPV-A strains. The genome and G-gene nt sequences of the Mexican aMPVs are closest to strain UK/8544/06 (97.22-97.47% and 95.07-95.83%, respectively). Various amino acid variations distinguish the Mexican isolates from each other, and other aMPV-A strains, most of which are in the G (n = 38), F (n = 12), and L (n = 19) proteins. Using our sequence data and publicly available aMPV-A data, we revised a previously published rRT-PCR test, which resulted in different cycling and amplification conditions for aMPV-A to make it more compatible with other commonly used rRT-PCR diagnostic cycling conditions. This is the first comprehensive sequence analysis of aMPVs in Mexico and demonstrates the value of nontargeted NGS to identify pathogens where targeted virus surveillance is likely not routinely performed.

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New variants of infectious bronchitis viruses (IBVs; Coronaviridae) continuously emerge despite routine vaccinations. Here, we report genome sequence variations of IBVs identified by random non-targeted next generation sequencing (NGS) of vaccine and field samples collected on FTA cards from commercial flocks in Mexico in 2019-2021. Paired-ended sequencing libraries prepared from rRNA-depleted RNAs were sequenced using Illumina MiSeq. IBV RNA was detected in 60.07% (n = 167) of the analyzed samples, from which 33 complete genome sequences were de novo assembled. The genomes are organized as 5'UTR-[Rep1a-Rep1b-S-3a-3b-E-M-4b-4c-5a-5b-N-6b]-3'UTR, except in eight sequences lacking non-structural protein genes (accessory genes) 4b, 4c, and 6b. Seventeen sequences have auxiliary S2' cleavage site located 153 residues downstream the canonically conserved primary furin-specific S1/S2 cleavage site. The sequences distinctly cluster into lineages GI-1 (Mass-type; n = 8), GI-3 (Holte/Iowa-97; n = 2), GI-9 (Arkansas-like; n = 8), GI-13 (793B; n = 14), and GI-17 (California variant; CAV; n = 1), with regional distribution in Mexico; this is the first report of the presence of 793B- and CAV-like strains in the country. Various point mutations, substitutions, insertions and deletions are present in the S1 hypervariable regions (HVRs I-III) across all 5 lineages, including in residues 38, 43, 56, 63, 66, and 69 that are critical in viral attachment to respiratory tract tissues. Nine intra-/inter-lineage recombination events are present in the S proteins of three Mass-type sequences, two each of Holte/Iowa-97 and Ark-like sequence, and one each of 793B-like and CAV-like sequences. This study demonstrates the feasibility of FTA cards as an attractive, adoptable low-cost sampling option for untargeted discovery of avian viral agents in field-collected clinical samples. Collectively, our data points to co-circulation of multiple distinct IBVs in Mexican commercial flocks, underscoring the need for active surveillance and a review of IBV vaccines currently used in Mexico and the larger Latin America region.

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The Mexican lineage H5N2 low pathogenic avian influenza viruses (LPAIVs) were first detected in 1994 and mutated to highly pathogenic avian influenza viruses (HPAIVs) in 1994-1995 causing widespread outbreaks in poultry. By using vaccination and other control measures, the HPAIVs were eradicated but the LPAIVs continued circulating in Mexico and spread to several other countries. To get better resolution of the phylogenetics of this virus, the full genome sequences of 44 H5N2 LPAIVs isolated from 1994 to 2011, and 6 detected in 2017 and 2019, were analysed. Phylogenetic incongruence demonstrated genetic reassortment between two separate groups of the Mexican lineage H5N2 viruses between 2005 and 2010. Moreover, the recent H5N2 viruses reassorted with previously unidentified avian influenza viruses. Bayesian phylogeographic results suggested that mechanical transmission involving human activity is the most probable cause of the virus spillover to Central American, Caribbean, and East Asian countries. Increased infectivity and transmission of a 2011 H5N2 LPAIV in chickens compared to a 1994 virus demonstrates improved adaptation to chickens, while low virus shedding, and limited contact transmission was observed in mallards with the same 2011 virus. The sporadic increase in basic amino acids in the HA cleavage site, changes in potential N-glycosylation sites in the HA, and truncations of PB1-F2 should be further examined in relation to the increased infectivity and transmission in poultry. The genetic changes that occur as this lineage of H5N2 LPAIVs continues circulating in poultry is concerning not only because of the effect of these changes on vaccination efficacy, but also because of the potential of the viruses to mutate to the highly pathogenic form. Continued vigilance and surveillance efforts, and the pathogenic and genetic characterization of circulating viruses, are required for the effective control of this virus.

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The effect of extrusion cooking on bioactive compounds in third-generation snacks (TGSE) and microwave-expanded snacks (MWSE) prepared using black bean, blue maize, and chard (FBCS) was evaluated. FBCS was extruded at different moisture contents (MC; 22.2-35.7%), extrusion temperatures (ET; 102-142 °C), and screw speeds (SP; 96-171 rpm). Total anthocyanin content (TAC), contents of individual anthocyanins, viz., cyanidin-3-glucoside, malvidin-3-glucoside, pelargonidin-3-glucoside, pelargonidin-3-5-diglucoside, and delphinidin-3-glucoside chloride, total phenolic content (TPC), antioxidant activity (AA), and color parameters were determined. TAC and individual anthocyanin levels increased with the reduction in ET. ET and MC affected the chemical and color properties; increase in ET caused a significant reduction in TPC and AA. Microwave expansion reduced anthocyanin content and AA, and increased TPC. Extrusion under optimal conditions (29% MC, 111 rpm, and 120 °C) generated products with a high retention of functional compounds, with high TAC (41.81%) and TPC (28.23%). Experimental validation of optimized process parameters yielded an average error of 13.73% from the predicted contents of individual anthocyanins. Results suggest that the TGSE of FBCS obtained by combining extrusion and microwave expansion achieved significant retention of bioactive compounds having potential physiological benefits for humans.

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Vaccines against virulent Newcastle disease virus (NDV) are widely available and can be protective, but improved vaccination protocols are needed to prevent clinical disease and reduce virus circulation. The present study evaluated the efficacy of two commercial vaccines alone or in combination: a live attenuated NDV vaccine (LV) and a recombinant herpesvirus of turkeys vector expressing the fusion protein of NDV and the virus protein 2 of infectious bursal disease virus (rHVT-ND-IBD). Chickens were vaccinated with one of four vaccination protocols: live vaccine (LV) at 1 and 11 days of age (DOA), rHVT ND-IBD and LV at 1 DOA, rHVT ND-IBD at 1 DOA boosted with an LV at 11 DOA, and rHVT ND-IBD at 1 DOA. The vaccinated birds were challenged at different time points (3 or 4 weeks of age) with the California 2018 virus. The mortality, clinical signs, mean death time (MDT), humoral response before and after vaccination, and virus shedding after challenge were evaluated. All vaccination protocols were able to prevent mortality, reduce virus shedding, and induce antibody levels before the challenge at 3 and 4 weeks-old. Overall, the antibody levels before the challenge at 4 weeks were significantly higher in all groups vaccinated with the rHVT ND-IBD when compared to levels in 3 week old birds. The combination of recombinant rHVT ND-IBD with a live vaccine at one-day-old seems to be a better combination, due to the absence of clinical signs, higher antibody levels pre and post-challenge, and reduced virus shedding at any time point after the challenge at 3 or 4 weeks of age with the California 2018 virus.

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Introducción Comparar los resultados radiológicos y recuperación postoperatoria de la función de la muñeca a mediano plazo en las fracturas inestables extra e intra articulares de radio distal, después de la reducción abierta con abordaje palmar y osteosíntesis con placa volar. Materiales y métodos Estudio de casos y controles en 52 pacientes divididos en los grupos de fracturas extra o intra articulares de acuerdo a la clasificación AO. Las radiografías preoperatorias y postoperatorias fueron evaluadas para determinar la restauración anatómica de la longitud radial, ángulo radial e inclinación palmar del radio. Se evaluó además el resultado, seis meses después de la cirugía, del rango activo de movimiento y la fuerza de agarre, a la vez, que se hizo evaluación del puntaje de QuickDASH. Resultados La edad promedio fue 53,7±16,8 (DE) años; el 63% mujeres. Las fracturas extra articulares fueron más frecuentes en las mujeres, pero las intra articulares presentaron distribución similar por sexo (p=0.023). La fuerza de agarre de la mano operada fue 73.7% y 67.5% de la mano opuesta en las fracturas extra e intra articulares, respectivamente. El puntaje QuickDASH promedio fue 2.36 (DE 2.01) y 4.16 (DE 3.82) en fracturas extra e intra articulares respectivamente (p=0.111). Discusión Para fracturas de radio distal la reducción abierta con abordaje palmar y estabilización con placa volar ofrece resultados funcionales satisfactorios tanto para las fracturas extra articulares como para las intra articulares, con una leve, aunque esperada, ventaja en las primeras debido a su menor complejidad.

Background To examine and compare the radiological results and postoperative recovery of the medium-term wrist function in unstable extra- and intra-articular fractures of distal radius, after open reduction with a palmar approach and osteosynthesis with a volar plate. Materials and methods Retrospective case control study in 52 patients, divided into groups according to the Orthopaedic Association (AO) classification as extra- or intra-articular fractures. The pre-operative and post-operative radiographs were evaluated to determine the anatomical restoration of the radial length, radial angle, and palmar inclination of the radius. The medium-term results of the active range of motion and the grip strength, as well as the Quick DASH score, were evaluated six months after surgery. Results The mean age was 53.7±16.8 (SD) years and 63% were women. Extra-articular fractures were more frequent in women, but intra-articular fractures had a similar distribution by gender (P=.023). The grip strength of the operated hand was 73.7% and 67.5% of the opposite hand in the extra- and intra-articular fractures, respectively. The mean Quick DASH score was 2.36 (SD 2.01) and 4.16 (SD 3.82) in extra- and intra-articular fractures, respectively (P=.111). Discussion For unstable distal radius fractures, open reduction with palmar approach and volar plate stabilisation offers satisfactory functional results for both extra-articular and intra-articular fractures, with a slight, but expected, advantage in the former due to its lesser complexity.

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La ruptura del tendón del músculo pectoral mayor es un evento raro para el cual está indicado la reparación quirúrgica en pacientes jóvenes y atléticos. La reparación puede hacerse de forma aguda o crónica, hasta o despúes de 8 semanas, respectivamente. Las reparaciones agudas han demostrado excelentes resultados, sin embargo, hasta el momento no se encuentran reportes de reparaciones quirúrgicas dentro de las primera 24 horas de la lesíon. Presentamos un caso de reparación quirúrgica inmediata de una ruptura del tendón del músculo pectoral mayor en un hombre de 45 años sin antecedentes de uso de esteroides, que ocurrió mientras levantaba pesas. El diagnóstico inmediato se confirmó con una RM de emergencia más la evaluación clínica. La intervención quirúrgica se realizó en menos de 24 horas. Se instauró un protocolo de rehabilitación gradual con ejercicios pasivos. Seis meses después de la cirugía, se encontró recuperación de la amplitud de movimiento y la fuerza del hombro, así como la restauración anatómica completa. Concluimos que la reparación quirúrgica precoz de una ruptura del tendón del músculo pectoral mayor, el primer día de la lesión, en menos de 24 horas, acompañada de una buena técnica quirúrgica y un protocolo de rehabilitación gradual, arrojó excelentes resultados seis meses después del trauma, similares a los reportados en la literatura para reparaciones agudas (<6 semanas). Nivel de evidencia: Nivel IV

The rupture of the pectoralis major muscle tendon in young and athletic patients is a rare event for which surgical repair is indicated. The repair can be acute or chronic, up to or after 8 weeks, respectively. Acute repair has shown excellent results, and so far there are no reports of surgical repairs within the first 24hours of the injury. A case is presented of the immediate surgical repair of a ruptured pectoralis major muscle tendon occurring in a 45-year-old man with no history of steroid use, while lifting weights. The immediate diagnosis was confirmed with an emergency MRI plus clinical evaluation. The surgical intervention was performed in less than 24hours. A protocol of gradual rehabilitation with passive exercises was established. Six months after surgery, there was recovery of range of motion and shoulder strength, as well as complete anatomical restoration. It is concluded that early surgical repair of a rupture of the pectoralis major muscle tendon on the first day of the injury, or in less than 24hours, accompanied by a good surgical technique and a gradual rehabilitation protocol, yielded excellent results six months after the trauma, similar to that reported in the literature for acute repairs. Evidence level: Level IV

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