Anabolic Incorporation of Oxalate by Oxalobacter formigenes

Cell-free lysates of the strict anaerobe Oxalobacter formigenes contained the following enzymatic activities: oxalyl coenzyme A reductase, glyoxylate carboligase, tartronic semialdehyde reductase, and glycerate kinase. NAD(P)-linked formate dehydrogenase, serine-glyoxylate aminotransferase, and NAD(P) transhydrogenase activities were not detected. These results support the hypothesis that O. formigenes assimilates carbon from oxalate by using the glycerate pathway, whereby oxalate is reduced to 3-phosphoglycerate before entering common biosynthetic pathways

Assimilation of Oxalate, Acetate, and CO2 by Oxalobacter formigenes

Oxalobacterformigenes is the only well-documented oxalate-degrading bacterium isolated from the gastrointestinal tract of animals. The production of ATP by Oxalobacter formigenes is centered around oxalate metabolism and oxalate is required for growth. A small amount of acetate (0.5 mM) is also required. Oxalate is decarboxylated to formate plus CO2 in nearly equimolar amounts. Experiments were conducted to determine which potential carbon sources (oxalate, acetate, formate, CO2) were assimilated by Oxalobacter formigenes and which metabolic pathways were operative in carbon assimilation. Measurements of the specific activities of total cell carbon after growth with different 14C-labeled precursors indicated that at least 54% of the total cell carbon was derived from oxalate and at least 7% was derived from acetate. Carbonate was also assimilated, but formate was not a significant source of cell carbon. Labeling patterns in amino acids from cells grown in [14C]oxalate or 14CO3 were different; however, in both cases 14C was widely distributed into most cellular amino acids. Carbon from [14C]acetate was less widely distributed and detected mainly in those amino acids known to be derived from α-ketoglutarate, oxaloacetate, and pyruvate. Cell-free extracts contained citrate synthase, isocitrate dehydrogenase, and malate dehydrogenase activities. The labeling observed in amino acids derived from acetate is in agreement with the function of these enzymes in biosynthesis and indicates that the majority of acetate carbon entered into amino acid biosynthesis via well-known pathways

Biosynthesis of amino acids by Oxalobacter formigenes: analysis using 13C-NMR

The gram-negative anaerobe Oxalobacter formigenes, grows on oxalate as the principal carbon and energy source, but a small amount of acetate is also required for growth. Experiments were conducted to determine the distribution and the position of label in cellular amino acids from cells grown on [13C]oxalate, [13C]acetate (1-13C, 2-13C, and U-13C), and 13CCO3. The labeling pattern (determined with NMR spectroscopy) of amino acids was consistent with their formation through common biosynthetic pathways. The majority of the carbons in the amino acids that are usually derived from pyruvate, oxaloacetate, α-ketoglutarate, 3-phosphoglycerate, and carbon in the aromatic amino acids were labeled by oxalate. Carbon from 13CO3 was assimilated primarily into amino acids expected to be derived from oxaloacetate and α-ketoglutarate. Approximately 60% of the acetate that was assimilated into amino acids was incorporated as a C2 unit into proline, arginine, glutamate, and leucine. The pattern of labeling from acetate in glutamate, arginine, and proline was consistent with acetate incorporation via citrate (si)-synthase and subsequent formation of α-ketoglutarate via the first third of the tricarboxylic acid pathway. Acetate was also assimilated into amino acids derived from pyruvate and oxaloacetate, but results indicated that this incorporation was as single carbon atoms. Based on these findings, cell-free extracts were assayed for several key biosynthetic enzymes. Enzymatic activities found included glutamate dehydrogenase, phosphoenolpyruvate carboxylase, and pyruvate carboxylase. These findings are consistent with proposed biosynthetic mechanisms

Polygenic transcriptome risk scores (PTRS) can improve portability of polygenic risk scores across ancestries

Background: Polygenic risk scores (PRS) are valuable to translate the results of genome-wide association studies (GWAS) into clinical practice. To date, most GWAS have been based on individuals of European-ancestry leading to poor performance in populations of non-European ancestry. Results: We introduce the polygenic transcriptome risk score (PTRS), which is based on predicted transcript levels (rather than SNPs), and explore the portability of PTRS across populations using UK Biobank data. Conclusions: We show that PTRS has a significantly higher portability (Wilcoxon p=0.013) in the African-descent samples where the loss of performance is most acute with better performance than PRS when used in combination

Perceptions and practices of farmers of indigenous poultry towards Salmonella infections in North-Central Nigeria

Background: Salmonella infections continue to be of global concern to poultry health, productivity, and public health. About 44% of the poultry in Nigeria are indigenous and kept in close interaction with farmers who are mostly rural dwellers and have limited access to veterinary and extension services.Aim: The perceptions and practices of farmers of indigenous poultry toward Salmonella infections were assessed to obtain and document baseline data that can be used to create awareness among farmers about these infections and their attendant public health implications.Methods: A cross-sectional approach using a multistage sampling method was used in this survey. A total of 419 farmers keeping indigenous poultry were interviewed using a pre-tested electronic questionnaire in three randomly selected states within North-Central Nigeria. Data were analyzed using descriptive and regression analysis.Results: Out of the 419 respondents, 138 (32.9%), 141 (33.7%), and 140 (33.4%) were from Benue, Kwara, and Plateau States, respectively. Of the 419, 55.4% were females, 40.8% were above 40 years, and 35.8% have over 10 years of farming experience. The majority of the poultry are not housed (58.5%) and farmers predominantly rear chickens (51.8%). Also, 49.9% of the birds were 1–6 months with 41.5% of the flock sizes being 11–20. Respondents had a poor level of perception toward Salmonella infection as the majority did not know that Salmonella affects poultry (89.3%) and that Salmonella infections are zoonotic (94.5%). Significant (p = 0.000) associations existed betweencategorized perception score and age, educational status, family size, and farming experience of farmers. There were significant (p = 0.000) associations of categorized practice scores with gender, age, education status, family size, and farming experience of farmers.Conclusion: This study has revealed the poor perception of farmers on Salmonella infections and has highlighted their practices. There is a need to raise awareness about these infections to improve indigenous poultry health and productivity as well as public health

Seasonality of reproduction in an ever-wet lowland tropical forest in Amazonian Ecuador

We thank Pablo Alvia, Alvaro Pérez, Zornitza Aguilar, Paola Barriga, Matt Priest, Caroline Whitefoord, and Gorky Villa for assistance in collecting data or identifying species; Elina Gomez for entry of trap data; Hugo Navarrete, Katya Romoleroux and the QCA herbarium staff, and David Lasso and the ECY staff for help with logistics and needed permitting; Rick Condit, Elizabeth Losos, Robin Foster, and Henrik Balslev for initial encouragement to work within the Yasuní Forest Dynamics Plot; Hugo Romero for initially summarizing the YFDP and SSP weather data sets; Pablo Jarrin for setting up the TEAM weather station, and David Lasso and Carlos Padilla for maintaining that equipment and making the data available; and the Ecuadorian Ministerio del Ambiente for permission to work in Yasuní National Park [No 014-2019-IC-PNY-DPAO/AVS, No 012-2018-IC-PNY593-DPAO/AVS, No 008-2017-IC-PNY-DPAO/AVS, No 012-2016-IC-FAU-FLO-DPAO-PNY, No 594-014-2015-FLO-MAE-DPAO-PNY, and earlier permits]. The Forest Dynamics Plot of Yasuní National Park has been made possible through the generous support of the Pontifical Catholic University of Ecuador (PUCE) funds of donaciones del impuesto a la renta, the Government of Ecuador, the US National Science Foundation, the Andrew W. Mellon Foundation, the Smithsonian Tropical Research Institute, and the University of Aarhus of Denmark. The phenology project began while NCG was at the Natural History Museum, London, with funding (2000–2004) from the Department of Botany (NHM), the Andrew W. Mellon Foundation, British Airways, and the Natural Environment Research Council (GR9/04037). It continued with NCG at Southern Illinois University Carbondale (2005–2023). We thank the Center for Tropical Forest Science for transitional funding (2006–2008, 2017–2018) and the National Science Foundation LTREB program for long-term funding (2006–2020; DEB-0614525, DEB-1122634, DEB-1754632, DEB-1754668).Peer reviewedPublisher PD

Identificación de las prácticas porcinas en granjas de la región Andina central de Colombia

The Colombian Swine Industry (CSI) has high pork carcass imports from the US due to the Free Trade Agreements (FTA) signed. The CSI is aimed at supplying domestic demand because not all departments are free of swine fever. In fact, pig farmers are focused on controlling the feeding costs and biosafety, and increasing the birth rate. The problem of the CSI is the search to increase profitability and eliminate intermediaries to be able to reach the consumer directly. This study is descriptive, and aims to identify the state-of-the-art of worldwide practices compared to the central Andean region of Colombia (CARC). For this, a measurement instrument was designed to identify the CSI practices, and the results were used to identify the improvement points for the CARC region. This instrument was validated with ten experts in terms of content, and these were not considered in the sampling. The results were obtained through a probabilistic sampling for a finite population comprised of pig farms located in the departments of Cundinamarca, Boyacá, Tolima, and Huila. The identified population was 191 pig farmers located in the CARC, and the sample calculated to be surveyed, was 50 pig farmers; however, the response rate was higher, and the measurement instrument was applied to 53 pig farmers. As a result, pig farmers want to create new business lines, but there is no trust with competitors. Besides, there is a deficit in technology, infrastructure, public policies, and economic incentives.La industria porcina colombiana (IPC) presenta altos niveles de importaciones de carne de cerdo en canal desde EE. UU. debido a los tratados de libre comercio, y está orientada a abastecer la demanda interna, ya que no todos los departamentos están libres de fiebre porcina. Los porcicultores se enfocan en controlar los costos de la alimentación y la bioseguridad y en aumentar la tasa de natalidad. El problema de la porcicultura colombiana radica en la búsqueda por aumentar la rentabilidad y eliminar los intermediarios para llegar directamente al consumidor final. El objetivo de este estudio descriptivo fue identificar la aplicación de las prácticas globales respecto a las de la región Andina central de Colombia (RACC). Para esto, se diseñó un instrumento de medición a fin de determinar las prácticas de la IPC y los resultados se utilizaron para definir estrategias de mejora. El contenido del instrumento se validó con siete expertos no considerados en el muestreo. Los resultados se obtuvieron mediante una muestra probabilística con población finita para las fincas porcinas localizadas en los departamentos de Cundinamarca, Boyacá, Tolima y Huila. La población identificada en la RACC fue de 191 porcicultores, y la muestra calculada para la entrevista fue de 50 fincas. No obstante, la tasa de respuesta fue más alta y se logró aplicar el instrumento de medición en 53 fincas porcinas. Se encontró que los porcicultores desean crear nuevas líneas de negocio, pero no tienen confianza en la competencia y existe un déficit en tecnología, infraestructura, políticas públicas e incentivos económicos

Propuesta de un protocolo de electro-estimulación para el tratamiento de úlceras por presión grado ii y iii

Antecedentes. El uso de estimulación eléctrica como terapia ayudante para la curación de heridas se remonta al año 1700. No obstante, a pesar de los avances científicos del siglo XX solo se conocen estudios experimentales hacia la década de los 70, cuando se inicia un proceso investigativo con el fin de conocer a mayor profundidad las propiedades eléctricas de la piel y el efecto que tiene la estimulación eléctrica en las reacciones fisiológicas de las células epidérmicas para aumentar y favorecer la curación de heridas. Objetivo. Proponer un protocolo de electro-estimulación para el tratamiento de úlceras por presión grados II y III, con base en la mejor evidencia reportada. Materiales y métodos. Búsqueda de artículos en diferentes bases de datos utilizando los títulos de términos médicos (Medical Subjects Headings) MESH, con la utilización de los vocablos “Wound Healing”, “Pressure Ulcer” y el sub encabezado “Electrophysiology” y “Electrical Stimulation”. Resultados. Después de realizar el análisis de la información se presenta la fundamentación de los parámetros que contiene la propuesta del protocolo (tipo de corriente, forma de onda, intensidad, campo eléctrico, frecuencia); se sustenta el cambio de polaridad, ubicación de electrodos y tiempo de tratamiento. Conclusión. Ante la heterogeneidad de parámetros en la aplicación de electro-estimulación en el proceso de cicatrización de úlceras por presión, se propone desde la evidencia, un protocolo de electro-estimulación fundamentado en los procesos biológicos, eléctricos y mecánicos de la piel

International Society for Pharmacoeconomics and Outcomes Research Comments on the American Society of Clinical Oncology Value Framework

As members of the International Society for Pharmacoeconomics and Outcomes Research, we read with great interest the new American Society of Clinical Oncology (ASCO) conceptual framework to assess the value of cancer treatment options.1 We applaud the Value in Cancer Care Task Force for proposing a conceptual framework to support clinicians and patients in assessing the value of new cancer treatments. We acknowledge the challenges facing clinician–patient decision making, particularly concerning cancer treatments. Like ASCO, we recognize that the cost of treatments is increasingly being placed on patients through cost sharing and that engaging patients as part of making individual treatment decisions is of high importance. The ASCO framework highlights the growing tension among patients, insurance companies, and product manufacturers in a dynamic health care environment. In that light, the framework deserves a field test, and we look forward to seeing the outcome of that experience. We also appreciate the opportunity to offer comments and suggestions on the ASCO framework at this early stage, and our membership stands ready to support ASCO in future enhancements