Polyphasic Approach and Potential Cyanotoxin Production by Planktothrix from the Río Grande de Comitán and Montebello Lakes National Park, Southern Mexico.

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.

Production and Physicochemical Characterization of the Gel Obtained in the Fermentation Process of Blue Corn Flour (Zea mays L.) with Colletotrichum gloeosporioides.

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.

Complete Genome Sequences of Avian Metapneumovirus Subtype B Vaccine Strains from Brazil.

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.

Detection and Genome Sequence Analysis of Avian Metapneumovirus Subtype A Viruses Circulating in Commercial Chicken Flocks in Mexico.

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.

Genome Sequence Variations of Infectious Bronchitis Virus Serotypes From Commercial Chickens in Mexico.

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.

Phylogenetic analysis, molecular changes, and adaptation to chickens of Mexican lineage H5N2 low-pathogenic avian influenza viruses from 1994 to 2019.

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.

Anthocyanins and Functional Compounds Change in a Third-Generation Snacks Prepared Using Extruded Blue Maize, Black Bean, and Chard: An Optimization.

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.

Protection conferred by commercial NDV live attenuated and double recombinant HVT vaccines against virulent California 2018 Newcastle disease virus (NDV) in chickens.

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.

Fracturas inestables de radio distal intra y extraarticulares: análisis comparativo de resultados a mediano plazo del tratamiento quirúrgico con placas volares / Intra- and extra-articular distal radius unstable fractures: comparative analysis of the medium-term results of volar plate surgical treatment

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.

Reparación quirúrgica inmediata de la ruptura del tendón del pectoral mayor causada por levantamiento de pesas. Reporte de caso / Immediate surgical repair of pectoralis major tendon rupture caused by weightlifting. Case Report

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

Caracterización clínica e histopatológica de niños con hepatitis autoinmune en un centro de referencia de Bogotá, Colombia / Clinical and histopathological characterization of children with autoimmune hepatitis at a referral center in Bogotá, Colombia

Resumen La hepatitis autoinmune (HAI) es una enfermedad hepática inflamatoria progresiva poco frecuente en niños y adolescentes, la cual es un reto diagnóstico para clínicos y patólogos. Describimos las características clínicas, bioquímicas e histopatológicas de 21 pacientes pediátricos con HAI diagnosticados en los últimos 14 años. Las biopsias hepáticas se reevaluaron para analizar detalladamente los hallazgos histopatológicos. De los 21 casos evaluados, 12 (57,1%) fueron mujeres, la mediana de edad fue 14 años, y 17 (80,9%) tenían HAI tipo 1. Los signos clínicos más frecuentes fueron ictericia (66,7%) y coluria (44,4%); también hubo evidencia de hipertensión portal con várices esofágicas (47,1%) y esplenomegalia (41,2%). El 11,8% de los pacientes tenía antecedentes de otras enfermedades autoinmunes. El 89,5%, 88,9% y 60,0% de los casos tenía elevación de aminotransferasas, hiperbilirrubinemia y bajos niveles de albúmina sérica, respectivamente. Las biopsias reevaluadas mostraron infiltrado linfoplasmocitario portal (94,4%), hepatitis de interfase (77,8%) y formación de rosetas (50,0%). En el 42,9% de las biopsias se hallaron inclusiones hialinas en las células de Kupffer. Cerca del 33,5% de los casos mostró cirrosis en la biopsia inicial. A pesar del tratamiento inmunosupresor, 4 pacientes requirieron trasplante hepático y 2 están en lista de espera. La HAI en niños puede manifestarse con ictericia y coluria, signos de hipertensión portal, aminotransferasas elevadas, hiperbilirrubinemia y anticuerpos circulantes. Las inclusiones hialinas en las células de Kupffer pueden ser un hallazgo útil en el diagnóstico histopatológico de la HAI en niños.

Abstract Autoimmune hepatitis (AIH) is a progressive inflammatory liver disease. It is uncommon in children and adolescents, and is a diagnostic challenge for clinicians and pathologists. We describe the clinical, biochemical and histopathological characteristics of 21 pediatric patients with AIH diagnosed in the last 14 years. Liver biopsies were reassessed to analyze histopathological findings in detail. Of the 21 cases evaluated, 12 (57.1%) were girls and young women, the median age was 14 years old, and 17 (80.9%) had type 1 AIH. The most frequent clinical signs were jaundice (66.7%), choluria (44.4%), evidence of portal hypertension with esophageal varices (47.1%), and splenomegaly (41.2%). Histories of other autoimmune diseases were found in 11.8% of these patients. Elevated levels of aminotransferases were found in 89.5% of the patients, hyperbilirubinemia was found in 88.9%, and 60.0% of the cases had low levels of serum albumin. Reassessed biopsies showed portal lymphoplasmocytic infiltrate (94.4%), interface hepatitis (77.8%) and rosette formation (50.0%). Hyaline inclusions were found in Kupffer cells in 42.9% of the biopsies. About 33.5% of the cases showed cirrhosis at the initial biopsy. Despite immunosuppressive treatment, four patients required liver transplantation and two are on the waiting list. AIH in children can manifest with jaundice, choluria, signs of portal hypertension, elevated aminotransferases, hyperbilirubinemia and circulating antibodies. Hyaline inclusions in Kupffer cells may be a useful finding in the histopathological diagnosis of AIH in children.

Rapid evolution of Mexican H7N3 highly pathogenic avian influenza viruses in poultry.

Highly pathogenic avian influenza (HPAI) virus subtype H7N3 has been circulating in poultry in Mexico since 2012 and vaccination has been used to control the disease. In this study, eight Mexican H7N3 HPAI viruses from 2015-2017 were isolated and fully sequenced. No evidence of reassortment was detected with other avian influenza (AI) viruses, but phylogenetic analyses show divergence of all eight gene segments into three genetic clusters by 2015, with 94.94 to 98.78 percent nucleotide homology of the HA genes when compared to the index virus from 2012. The HA protein of viruses from each cluster showed a different number of basic amino acids (n = 5-7) in the cleavage site, and six different patterns at the predicted N-glycosylation sites. Comparison of the sequences of the Mexican lineage H7N3 HPAI viruses and American ancestral wild bird AI viruses to characterize the virus evolutionary dynamics showed that the nucleotide substitution rates in PB2, PB1, PA, HA, NP, and NS genes greatly increased once the virus was introduced into poultry. The global nonsynonymous and synonymous ratios imply strong purifying selection driving the evolution of the virus. Forty-nine positively selected sites out of 171 nonsynonymous mutations were identified in the Mexican H7N3 HPAI viruses, including 7 amino acid changes observed in higher proportion in North American poultry origin AI viruses isolates than in wild bird-origin viruses. Continuous monitoring and molecular characterization of the H7N3 HPAI virus is important for better understanding of the virus evolutionary dynamics and further improving control measures including vaccination.

Virulent Newcastle disease viruses from chicken origin are more pathogenic and transmissible to chickens than viruses normally maintained in wild birds.

Five, class II, virulent Newcastle disease virus (vNDV) isolates of different genotypes from different host species were evaluated for their ability to infect, cause disease, and transmit to naïve chickens. Groups of five birds received a low, medium, or high dose, by the oculonasal route, of one of the following vNDV: three chicken-origin, one cormorant-origin, and one pigeon-origin. Three naïve birds were added to each group at two days post-inoculation (DPI) to evaluate transmission. Virus shedding was quantified from swabs (2/4/7 DPI), and seroconversion was evaluated at 14 DPI. All inoculated and contact birds in the chicken-origin vNDV groups succumbed to infection, displaying clinical signs typical of Newcastle disease and shed virus titers above 6 log10 EID50/ml. Birds receiving a high and medium dose of the cormorant virus showed primarily neurological clinical signs with 80% and 60% mortality, respectively. The chickens showing clinical disease shed virus at titers below 4 log10 EID50/ml, and the remaining bird in the high dose group seroconverted with a high HI titer. For the pigeon-origin virus, no clinical signs were observed in any of the birds, but all 5 chickens in the high challenge dose and one bird in the medium challenge group shed virus at mean titers of 3.1 and 2.2 log10 EID50/ml, respectively. Overall, the chicken-origin viruses infected chickens and efficiently transmitted to naïve birds, while the cormorant- and pigeon-origin viruses infected chickens only at the higher doses and did not transmit to other birds.

Bilateral Macrodactyly of the Halluces in an Adolescent Girl Corrected with Shortening Osteotomies of the First Metatarsal and the Phalangeal Bones: A Case Report.

CASE: A 14-year-old girl presented with painful high-arched feet and unusual, asymptomatic, bilateral macrodactyly of the halluces. After a year of observation, a surgical reduction was performed because of the psychological effect that the abnormality had on the patient. Bilateral shortening osteotomies of the metatarsal and the proximal phalangeal bones were performed. At 2 months after surgery, complete bone healing and alignment had been achieved. At the 5-year follow-up, we noted fully functional big toes, plantigrade feet, bilateral proper toe formula, and extreme patient satisfaction with the cosmetic results. CONCLUSION: Dual osteotomies for toe shortening in a patient with bilateral nondysmorphic macrodactyly provided appropriate length reduction and satisfactory aesthetic and functional results.

Physicochemical Changes and Resistant-Starch Content of Extruded Cornstarch with and without Storage at Refrigerator Temperatures.

Effects of extrusion cooking and low-temperature storage on the physicochemical changes and resistant starch (RS) content in cornstarch were evaluated. The cornstarch was conditioned at 20%-40% moisture contents and extruded in the range 90-130 °C and at screw speeds in the range 200-360 rpm. The extrudates were stored at 4 °C for 120 h and then at room temperature. The water absorption, solubility index, RS content, viscoelastic, thermal, and microstructural properties of the extrudates were evaluated before and after storage. The extrusion temperature and moisture content significantly affected the physicochemical properties of the extrudates before and after storage. The RS content increased with increasing moisture content and extrusion temperature, and the viscoelastic and thermal properties showed related behaviors. Microscopic analysis showed that extrusion cooking damaged the native starch structure, producing gelatinization and retrogradation and forming RS. The starch containing 35% moisture and extruded at 120 °C and 320 rpm produced the most RS (1.13 g/100 g) after to storage at low temperature. Although the RS formation was low, the results suggest that extrusion cooking could be advantageous for RS production and application in the food industry since it is a pollution less, continuous process requiring only a short residence time.

Incidence and prognosis of ventilator-associated tracheobronchitis (TAVeM): a multicentre, prospective, observational study.

BACKGROUND: Ventilator-associated tracheobronchitis has been suggested as an intermediate process between tracheobronchial colonisation and ventilator-associated pneumonia in patients receiving mechanical ventilation. We aimed to establish the incidence and effect of ventilator-associated tracheobronchitis in a large, international patient cohort. METHODS: We did a multicentre, prospective, observational study in 114 intensive care units (ICU) in Spain, France, Portugal, Brazil, Argentina, Ecuador, Bolivia, and Colombia over a preplanned time of 10 months. All patients older than 18 years admitted to an ICU who received invasive mechanical ventilation for more than 48 h were eligible. We prospectively obtained data for incidence of ventilator-associated lower respiratory tract infections, defined as ventilator-associated tracheobronchitis or ventilator-associated pneumonia. We grouped patients according to the presence or absence of such infections, and obtained data for the effect of appropriate antibiotics on progression of tracheobronchitis to pneumonia. Patients were followed up until death or discharge from hospital. To account for centre effects with a binary outcome, we fitted a generalised estimating equation model with a logit link, exchangeable correlation structure, and non-robust standard errors. This trial is registered with ClinicalTrials.gov, number NCT01791530. FINDINGS: Between Sept 1, 2013, and July 31, 2014, we obtained data for 2960 eligible patients, of whom 689 (23%) developed ventilator-associated lower respiratory tract infections. The incidence of ventilator-associated tracheobronchitis and that of ventilator-associated pneumonia at baseline were similar (320 [11%; 10·2 of 1000 mechanically ventilated days] vs 369 [12%; 8·8 of 1000 mechanically ventilated days], p=0·48). Of the 320 patients with tracheobronchitis, 250 received appropriate antibiotic treatment and 70 received inappropriate antibiotics. 39 patients with tracheobronchitis progressed to pneumonia; however, the use of appropriate antibiotic therapy for tracheobronchitis was associated with significantly lower progression to pneumonia than was inappropriate treatment (19 [8%] of 250 vs 20 [29%] of 70, p<0·0001; crude odds ratio 0·21 [95% CI 0·11-0·41]). Significantly more patients with ventilator-associated pneumonia died (146 [40%] of 369) than those with tracheobronchitis (93 [29%] of 320) or absence of ventilator-associated lower respiratory tract infections (673 [30%] of 2271, p<0·0001). Median time to discharge from the ICU for survivors was significantly longer in the tracheobronchitis (21 days [IQR 15-34]) and pneumonia (22 [13-36]) groups than in the group with no ventilator-associated lower respiratory tract infections (12 [8-20]; hazard ratio 1·65 [95% CI 1·38-1·97], p<0·0001). INTERPRETATION: This large database study emphasises that ventilator-associated tracheobronchitis is a major health problem worldwide, associated with high resources consumption in all countries. Our findings also show improved outcomes with use of appropriate antibiotic treatment for both ventilator-associated tracheobronchitis and ventilator-associated pneumonia, underlining the importance of treating both infections, since inappropriate treatment of tracheobronchitis was associated with a higher risk of progression to pneumonia. FUNDING: None.

Potency, efficacy, and antigenic mapping of H7 avian influenza virus vaccines against the 2012 H7N3 highly pathogenic avian influenza virus from Mexico.

In the spring of 2012 an outbreak of H7N3 highly pathogenic (HP) avian influenza virus (AIV) occurred in poultry in Mexico. Vaccination was implemented as a control measure, along with increased biosecurity and surveillance. At that time there was no commercially available H7 AIV vaccine in North America; therefore, a recent H7N3 wild bird isolate of low pathogenicity from Mexico (A/cinnamon teal/Mexico/2817/2006 H7N3) was selected and utilized as the vaccine seed strain. In these studies, the potency and efficacy of this vaccine strain was evaluated in chickens against challenge with the 2012 Jalisco H7N3 HPAIV. Although vaccine doses of 256 and 102 hemagglutinating units (HAU) per bird decreased morbidity and mortality significantly compared to sham vaccinates, a dose of 512 HAU per bird was required to prevent mortality and morbidity completely. Additionally, the efficacy of 11 other H7 AIV vaccines and an antigenic map of hemagglutination inhibition assay data with all the vaccines and challenge viruses were evaluated, both to identify other potential vaccine strains and to characterize the relationship between genetic and antigenic distance with protection against this HPAIV. Several other isolates provided adequate protection against the 2012 Jalisco H7N3 lineage, but antigenic and genetic differences were not clear indicators of protection because the immunogenicity of the vaccine seed strain was also a critical factor.

Characterization of the 2012 highly pathogenic avian influenza H7N3 virus isolated from poultry in an outbreak in Mexico: pathobiology and vaccine protection.

In June of 2012, an H7N3 highly pathogenic avian influenza (HPAI) virus was identified as the cause of a severe disease outbreak in commercial laying chicken farms in Mexico. The purpose of this study was to characterize the Mexican 2012 H7N3 HPAI virus (A/chicken/Jalisco/CPA1/2012) and determine the protection against the virus conferred by different H7 inactivated vaccines in chickens. Both adult and young chickens intranasally inoculated with the virus became infected and died at between 2 and 4 days postinoculation (p.i.). High virus titers and viral replication in many tissues were demonstrated at 2 days p.i. in infected birds. The virus from Jalisco, Mexico, had high sequence similarity of greater than 97% to the sequences of wild bird viruses from North America in all eight gene segments. The hemagglutinin gene of the virus contained a 24-nucleotide insert at the hemagglutinin cleavage site which had 100% sequence identity to chicken 28S rRNA, suggesting that the insert was the result of nonhomologous recombination with the host genome. For vaccine protection studies, both U.S. H7 low-pathogenic avian influenza (LPAI) viruses and a 2006 Mexican H7 LPAI virus were tested as antigens in experimental oil emulsion vaccines and injected into chickens 3 weeks prior to challenge. All H7 vaccines tested provided ≥90% protection against clinical disease after challenge and decreased the number of birds shedding virus and the titers of virus shed. This study demonstrates the pathological consequences of the infection of chickens with the 2012 Mexican lineage H7N3 HPAI virus and provides support for effective programs of vaccination against this virus in poultry.

Has H. pylori prevalence in bleeding peptic ulcer been underestimated? A meta-regression.

OBJECTIVES: It has been suggested that prevalence of Helicobacter pylori (Hp) in peptic ulcer bleeding (PUB) is lower than that in non-complicated ulcers. As Hp infection is elusive in PUB, we hypothesized that this low prevalence could be related to an insufficiently intensive search for the bacteria. The aim of the study was to evaluate whether the prevalence of Hp in PUB depends on the diagnostic methods used in a given study. METHODS: A systematic review was performed of studies assessing the prevalence of Hp infection in patients with PUB. Data were extracted in duplicate. Univariate and multivariate random-effects meta-regression analyses were performed to determine the factors that explained the differences in Hp prevalence between studies. RESULTS: The review retrieved 71 articles, including 8,496 patients. The mean prevalence of Hp infection in PUB was 72%. The meta-regression analysis showed that the most significant variables associated with a high prevalence of Hp infection were the use of a diagnostic test delayed until at least 4 weeks after the PUB episode-odds ratio: 2.08, 95% confidence interval: 1.10-3.93, P=0.024-and a lower mean age of patients-odds ratio: 0.95 per additional year, 95% confidence interval: 0.92-0.99, P=0.008. CONCLUSIONS: Studies that performed a delayed test and those including younger patients found a higher prevalence of Hp, approaching that recorded in cases of non-bleeding ulcers. These results suggest that the low prevalence of Hp infection described in PUB may be related to the methodology of the studies and to patients' characteristics, and that the true prevalence of Hp in PUB is still to be determined. Our data also support the recent recommendations of the International Consensus on Non-Variceal Upper Gastrointestinal Bleeding regarding the performance of a delayed diagnostic test when Hp tests carried out during the acute PUB episode are negative.

Pandemic H1N1 influenza virus in Chilean commercial turkeys with genetic and serologic comparisons to U.S. H1N1 avian influenza vaccine isolates.

Beginning in April 2009, a novel H1N1 influenza virus caused acute respiratory disease in humans, first in Mexico and then around the world. The resulting pandemic influenza A H1N1 2009 (pH1N1) virus was isolated in swine in Canada in June 2009 and later in breeder turkeys in Chile, Canada, and the United States. The pH1N1 virus consists of gene segments of avian, human, and swine influenza origin and has the potential for infection in poultry following exposure to infected humans or swine. We examined the clinical events following the initial outbreak of pH1N1 in turkeys and determined the relatedness of the hemagglutinin (HA) gene segments from the pH1N1 to two H1N1 avian influenza (AI) isolates used in commercial turkey inactivated vaccines. Overall, infection of turkey breeder hens with pH1N1 resulted in -50% reduction of egg production over 3-4 weeks. Genetic analysis indicated one H1N1 AI vaccine isolate (Alturkey/North Carolina/17026/1988) contained approximately 92% nucleotide sequence similarity to the pH1N1 virus (A/Mexico/4109/2009); whereas, a more recent AI vaccine isolate (A/ swine/North Carolina/00573/2005) contained 75.9% similarity. Comparison of amino acids found at antigenic sites of the HA protein indicated conserved epitopes at the Sa site; however, major differences were found at the Ca2 site between pH1N1 and A/ turkey/North Carolina/127026/1988. Hemagglutinin-inhibition (HI) tests were conducted with sera produced in vaccinated turkeys in North Carolina to determine if protection would be conferred using U.S. AI vaccine isolates. HI results indicate positive reactivity (HI titer > or = 5 log2) against the vaccine viruses over the course of study. However, limited cross-reactivity to the 2009 pH1N1 virus was observed, with positive titers in a limited number of birds (6 out of 20) beginning only after a third vaccination. Taken together, these results demonstrate that turkeys treated with these vaccines would likely not be protected against pH1N1 and current vaccines used in breeder turkeys in the United States against circulating H1N1 viruses should be updated to ensure adequate protection against field exposure.