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El creciente problema de resistencia a los antihelmínticos (AHs) convencionales en poblaciones de nematodos gastrointestinales (NGI), ha motivado la búsqueda de alternativas para su control en los rebaños de ovinos y caprinos, como es el caso de los metabolitos secundarios de plantas. En el presente trabajo se evaluó la actividad AH in vitro de curcumina (CUR) contra tres aislados del nematodo de rumiantes Haemonchus contortus con diferente susceptibilidad a los AHs convencionales. Se utilizaron las pruebas in vitro de inhibición de la eclosión de huevos (IEH), inhibición de la migración larvaria (IML), inhibición del desenvaine larvario (IDL) y mortalidad a las 72 h de L3 sin vaina. Las pruebas se realizaron usando un intervalo de concentraciones de 0 - 8.5 μg CUR/ml. Solamente la prueba de IDL fue realizada con un intervalo de concentración de 0 - 17.3 μg CUR/ml. Se obtuvieron las curvas de concentración-respuesta en una regresión log-logística y se realizó un diseño completamente al azar mediante un ANOVA. La CUR no presentó actividad AH en las pruebas de IEH, IML y mortalidad, pero sí demostró efecto AH significativo en la prueba de IDL. Este efecto fue más potente contra el aislado FMVZ-UADY (CE50= 1.9 μg/ml, IC95% 1.58-2.31), seguido por el aislado Paraíso (CE50= 3.2 μg/ml, IC95% 2.69-3.81) y CENID-SAI, INIFAP (CE50= 7.0 μg/ml; IC95% 6.58-7.43). Se concluye que la CUR tiene efecto AH contra el desenvaine de las L3 de H. contortus pero no afecta la eclosión de huevos, la migración de L3 o la mortalidad de L3 sin vaina a las dosis evaluadas.

The use of animals, fungi, and plants as a source of bioactive compounds has been widely practiced in diverse cultures throughout the world, particularly in alcoholic drinks. The nature of the biological material, method of preparation and alcohol concentration play a predominant role in the extraction of bioactive compounds and the achievement of desired results. However, certain aspects must be considered to guarantee the innocuity of these drinks and reduce the risk of intoxication, infections and allergic reactions, aspects which are sometimes overlooked. In addition, the implications of using threatened or protected species must be considered to reduce the negative impact on their populations. The authors recommend the establishment of production systems which guarantee products with adequate quality controls and ensure the benefits to the consumer.

Objetivo. Exponer el método de observación visual de categorías de bocados para estimar el consumo de rumiantes en agostaderos, su complejidad, fortalezas y limitantes. Materiales y métodos. La revisión se focalizó en los trabajos que mejoraron el método (validación, aumento en la precisión de la estimación, repetibilidad y fiabilidad) y en la identificación de las fortalezas y limitantes del método, se presentan ejemplos de su uso en etología, nutrición y parasitología. Resultados. El método consiste en un conjunto de técnicas que integran elementos de etología, botánica, nutrición y estadística, resultando en una estimación confiable y detallada de la cantidad y calidad de follaje ingerido por los rumiantes. La validación fue efectuada por diversos autores en estudios que abarcan desde los marcadores de óxido de cromo hasta el uso de animales fistulados. El método de observación de bocados evolucionó a lo largo de los años incorporando mejoras como el refinamiento de las categorías de bocados según el tamaño y forma de las partes de las plantas consumidas (tablas de categorías de bocados), y el uso de protocolos de habituación en los animales a observar para evitar influenciar la conducta de ingestión de los animales bajo estudio. Conclusión. Es un método de bajo costo, respetuoso del bienestar animal, no interfiere con la conducta habitual, la estimación entre observadores tiene buena repetibilidad y exactitud, la estimación es cuantitativa y detallada. Sin embargo, su implementación es laboriosa, requiere conocimientos de etología, botánica y entrenamiento en la identificación de las categorías de bocados. Puede considerarse un método vigente, aplicable si se dispone del recurso humano capacitado.

Background: Goats are increasingly being used as surgical models in animal experiments. Some ruminant parasitological studies require collecting adult nematodes directly from the abomasum of donor animals. A methodology to collect those adult worms in vivo could avoid the unnecessary sacrifice of donor animals. Objective: To describe an abomasotomy technique to obtain adult Haemonchus contortus from live goats and evaluate the immediate post-surgical recovery time. Methodology: Nine worm-free adult goats were infected with 6000 H. contortus L3. The monospecific infection was confirmed on day 28 post-infection. The anesthetic procedure included fentanyl (10 μg * kg BW-1 load dose (LD) and 10 μg * kg BW-1 hour in constant-rate-infusion (CRI), lidocaine (2 mg * kg LD-1 and 50 μg * kg BW-1 minute CRI), ketamine (1.5 mg * kg-1 and 50 μg * kg BW-1 min CRI) and propofol (4 mg * kg LD-1 and 0.4 mg * kg BW-1 min CRI). The surgical protocol consisted of eight “surgical time-points”. Purposeful animal movement in response to surgical stimulation, or any changes in the autonomic response (> 20% from baseline values of HR and arterial blood pressure (SAP, MAP, and DAP)) were used as criteria to identify trans-surgical nociception. Post-surgical pain was evaluated once daily with the wound healing evaluation. Results: The surgical protocol lasted 1 h, allowing the recovery of adult H. contortus from live goats. The anesthetic protocol successfully controlled trans-surgical pain, with only two animals crossing the HR threshold (>20%) from T2 to T6. Post-surgical recovery (“time to extubation” and “time to standing”) was achieved before 1 h, while animals consumed water after only 4 h post-surgery. Goats did not require rescue analgesia, and suture withdrawal was achieved 7 days post-surgery without complications. Impications: The abomasotomy technique here described can be used for parasitological studies in small ruminants when the collection of nematodes is required from live animals. Conclusions: The anesthetic and surgical protocol here described is a viable and rapid alternative for the collection of nematodes from the abomasum of live goats with minimal pain and rapid postsurgical recovery.

Abstract Dual-degree MD-PhD programs have historically lacked diversity of race, ethnicity, gender, sexual orientation, and other facets of identity. Like MD- and PhD-granting programs, MD-PhD program training environments are also marked by structural barriers that negatively impact measurable academic outcomes of underrepresented and/or marginalized students in academic medicine (racial and ethnic minority groups considered underrepresented by the National Institute of Health, sexual and gender minorities, individuals with disabilities, and individuals of low socioeconomic status). In this article, we review the existing literature on MD-PhD program disparities affecting students from these groups and provide recommendations grounded on the reviewed evidence. Our literature review identified four generalizable barriers that can impact the training outcomes of students from these marginalized and/or underrepresented groups: 1) discrimination and bias, 2) impostor syndrome and stereotype threat, 3) lack of identity-similar mentors, and 4) suboptimal institutional policies and procedures. We propose goal-oriented interventions that may begin to ameliorate the disparities present in MD-PhD program training environments that affect students from marginalized and/or underrepresented groups in academic medicine.

Background: There are over 1,500,000 species of mushrooms worldwide and approximately 20,000 of them are present in Mexico where native cultures use some species of wild mushrooms for different purposes. Among those mushroom species approximately 200 are edible, the genus Pleurotus spp the second most produced and consumed on the American continent. The production of Pleurotus spp. have had rapid development in the food industry, due to their nutraceutical and pharmacological properties, ease of growth and adaptation to the diversity of organic substrates on wich they can grow. Other edible mushrooms, such as Lentinula edodes (Shiitake), have also been used for their nutraceutical properties. Objective: The present work provides a general and updated overview of the advances in the use of the secondary metabolites of edible macromycetes and their by-products for the control of parasites in the agricultural sector. The methodological strategy used was a detailed bibliographic review in different sources such as PubMed for the National Center for Biotechnology Information (NCBI), ResearchGate, Scopus, Science direct, among others. Main findings: The review process showed that nine species of edible mushrooms exhibited in vitro nematicidal activity against parasitic nematodes of plants (Nacobbus aberrans and Meloidogyne enterolobii) and animals (Haemonchus contortus), including Pleurotus spp (P. ostreatus, P. djamor, P. eryngii, P. pulmonarius, P. cornucopiae), Lentinula edodes (Shiitake), Panus sp, Coprinus comatus and Hericium erinaceus. The antiparasitic effect has been attributed to diverse chemical compounds such as fatty acids, polyphenols and terpenes, which have been isolated from macromycetes and their by-products (degraded substrates of macromycetes). Our research group has pioneered the study of the uses and applications of secondary compounds derived from edible mushrooms and their by-products for parasite control in the agricultural sector. Conclusion: This work sought edible mushroom products with nutraceutical potential that can satisfy the demands of producers and contribute to food self-sufficiency in Mexico.

Abstract Background The production of chemicals via bio-based routes is held back by limited easy-to-use stabilisation systems. A wide range of plasmid stabilisation mechanisms can be found in the literature, however, how these mechanisms effect genetic stability and how host strains still revert to non-productive variants is poorly understood at the single-cell level. This phenomenon can generate difficulties in production-scale bioreactors as different populations of productive and non-productive cells can arise. To understand how to prevent non-productive strains from arising, it is vital to understand strain behaviour at a single-cell level. The persistence of genes located on plasmid vectors is dependent on numerous factors but can be broadly separated into structural stability and segregational stability. While structural stability refers to the capability of a cell to resist genetic mutations that bring about a loss of gene function in a production pathway, segregational stability refers to the capability of a cell to correctly distribute plasmids into daughter cells to maintain copy number. A lack of segregational stability can rapidly generate plasmid-free variants during replication, which compromises productivity. Results Citramalate synthase expression was linked in an operon to the expression of a fluorescent reporter to enable rapid screening of the retention of a model chemical synthesis pathway in a continuous fermentation of E. coli. Cells without additional plasmid stabilisation started to lose productivity immediately after entering the continuous phase. Inclusion of a multimer resolution site, cer, enabled a steady-state production period of 58 h before a drop in productivity was detected. Single-cell fluorescence measurements showed that plasmid-free variants arose rapidly without cer stabilisation and that this was likely due to unequal distribution of plasmid into daughter cells during cell division. The addition of cer increased total chemical yield by more than 50%. Conclusions This study shows the potential remains high for plasmids to be used as pathway vectors in industrial bio-based chemicals production, providing they are correctly stabilised. We demonstrate the need for accessible bacterial ‘toolkits’ to enable rapid production of known, stabilised bacterial production strains to enable continuous fermentation at scale for the chemicals industry.

Due to the increasing populations of anthelmintic-resistant gastrointestinal nematodes and as a consequence of the adverse effects of synthetic drugs, this study focuses on the search for secondary metabolites with nematocidal activity from the edible mushroom Pleurotus djamor using The proton nuclear magnetic resonance (1H-NMR) metabolomics. The highest activity was shown by the ethyl acetate fractions of mycelium (EC50 290.8 µg/mL) and basidiomes (EC50 282.7 µg/mL). Principal component analysis (PCA) and hierarchical data analysis (HCA) of the 1H-NMR metabolic profiles data showed that the ethanolic extracts, the ethyl acetate, butanol, and water fractions from mycelium have different metabolic profiles than those from basidiomes, while low polarity (hexane) fractions from both stages of fungal development show similar profiles. Orthogonal partial least squares discriminant analysis (OPLS-DA) allowed the identification of signals in the 1H-NMR metabolic profile associated with nematocidal activity. The signals yielded via OPLS-DA and bidimensional NMR analysis allowed the identification of uracil as a component in the ethyl acetate fraction from basidiomes, with an EC50 of 237.7 µg/mL. The results obtained showed that chemometric analyses of the 1H-NMR metabolic profiles represent a viable strategy for the identification of bioactive compounds from samples with complex chemical profiles.

We evaluated the relationship between individual and herd GIN infection level, nutrition, production performance and anemia parameters in a tropical farm context. Fifty-four female goats were monitored to assess their body condition score (BCS, nutritional status indicator), live weight (LW) and LW gain (LWG, both used as production level indicators), FAMACHA© and hematocrit (HT, both used as anemia indicators). Goats browsed for 4 h in a tropical forest and received balanced feed and chopped grass. The eggs per gram of feces (EPG) indicated the GIN burden, with fecal samples obtained at 7:00 (AM) and 15:00 h (PM.) from each goat at six sampling points during the study. The variables and their relationship with GIN burdens were analyzed using Kruskall–Wallis, ANOVA and Friedman tests and Spearman correlations. The fecal samples obtained in the AM and PM can be equally representative of parasitic burdens (similar and highly correlated). However, the EPG of individual goats from periods of 30 days apart can be considered independent. The BCS and LWG varied between sampling times (p < 0.05), whereas EPG, LW and HT did not (p > 0.05). The GIN burden was negatively correlated with HT and BCS (−0.21, p = 0.01 for each one). The individual pattern of infection demonstrates the true impact of GINs on their hosts. Additionally, feeding and nutritional status may present important variations influencing the performance of the goats more than the impact of GINs under the farm conditions of the present study. However, GIN infection contributed to the variation in goat health and productivity in this tropical farm.

The implementation of Clinical Practice Guidelines, with effective evidence-based interventions, has improved the results of managing patients with ST-segment elevation acute myocardial infarction in high-income countries, however, the same is not true in countries with medium and low incomes, where there are large gaps in its implementation, due to multiple factors. This Clinical Practice Guideline refers to patients presenting with ischemic symptoms or their equivalents and persistent ST-segment elevation on the electrocardiogram. This guideline does not address elements directly related to percutaneous coronary intervention procedures or surgical myocardial revascularization.

Introducción: la gestión de la ciencia a partir de la introducción de la innovación en los deportes de alto rendimiento constituye una prioridad en la actualidad. en el presente trabajo se parte de un diagnóstico inicial, lo cual permite formular el problema científico: ¿Cómo contribuir a la introducción de la innovación en el deporte de alto rendimiento en el contexto guantanamero? Objetivo: diseñar una concepción teórica metodológica concretada en una metodología de innovación mediante servicios científicos técnicos especializados para el alto rendimiento en el contexto guantanamero a partir de una nueva mirada con un enfoque integrador y renovador. Materiales y métodos: durante la investigación se utilizaron métodos científicos teóricos, empíricos y matemático y/o estadístico, los cuales fueron aplicados a 32 entrenadores y 31 directivos para un total de 62 sujetos. Resultados: se logró un mayor grado de compromiso con la introducción de la innovación en el deporte de alto rendimiento, se identifican las relaciones que se establecen entre el sistema categorial de la innovación mediante servicios científicos técnicos especializados. Conclusiones: la concepción teórica metodológica propuesta se revela, tanto en la teoría como en la práctica una solución de la problemática relacionada con la introducción de la innovación, al considerarse un nuevo punto de vista y el conjunto de categorías, las cuales se diseñan en función de que su inserción sea sistemática y continua a partir de su articulación horizontal y vertical sustentadas en principios de apoyo a la innovación, elaborados para el logro de ese fin.