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1.
Immunity ; 52(2): 357-373.e9, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-32049051

RESUMEN

Clearance of apoptotic cells by macrophages prevents excessive inflammation and supports immune tolerance. Here, we examined the effect of blocking apoptotic cell clearance on anti-tumor immune response. We generated an antibody that selectively inhibited efferocytosis by phagocytic receptor MerTK. Blockade of MerTK resulted in accumulation of apoptotic cells within tumors and triggered a type I interferon response. Treatment of tumor-bearing mice with anti-MerTK antibody stimulated T cell activation and synergized with anti-PD-1 or anti-PD-L1 therapy. The anti-tumor effect induced by anti-MerTK treatment was lost in Stinggt/gt mice, but not in Cgas-/- mice. Abolishing cGAMP production in Cgas-/- tumor cells, depletion of extracellular ATP, or inactivation of the ATP-gated P2X7R channel also compromised the effects of MerTK blockade. Mechanistically, extracellular ATP acted via P2X7R to enhance the transport of extracellular cGAMP into macrophages and subsequent STING activation. Thus, MerTK blockade increases tumor immunogenicity and potentiates anti-tumor immunity, which has implications for cancer immunotherapy.


Asunto(s)
Macrófagos/inmunología , Proteínas de la Membrana/metabolismo , Neoplasias/inmunología , Nucleótidos Cíclicos/metabolismo , Receptores Purinérgicos P2X7/metabolismo , Tirosina Quinasa c-Mer/inmunología , Adenosina Trifosfato/metabolismo , Animales , Apoptosis , Antígeno B7-H1/inmunología , Células Cultivadas , Femenino , Inmunidad Innata , Inmunoterapia , Interferón Tipo I/metabolismo , Macrófagos/metabolismo , Proteínas de la Membrana/genética , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Neoplasias/metabolismo , Neoplasias/patología , Neoplasias/terapia , Nucleotidiltransferasas/deficiencia , Nucleotidiltransferasas/metabolismo , Fagocitosis , Receptor de Muerte Celular Programada 1/inmunología , Receptores Purinérgicos P2X7/deficiencia , Transducción de Señal/inmunología , Ensayos Antitumor por Modelo de Xenoinjerto , Tirosina Quinasa c-Mer/genética
2.
J Immunol ; 210(8): 1166-1176, 2023 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-36881873

RESUMEN

Efferocytosis is a phagocytic process by which apoptotic cells are cleared by professional and nonprofessional phagocytic cells. In tumors, efferocytosis of apoptotic cancer cells by tumor-associated macrophages prevents Ag presentation and suppresses the host immune response against the tumor. Therefore, reactivating the immune response by blockade of tumor-associated macrophage-mediated efferocytosis is an attractive strategy for cancer immunotherapy. Even though several methods have been developed to monitor efferocytosis, an automated and high-throughput quantitative assay should offer highly desirable advantages for drug discovery. In this study, we describe a real-time efferocytosis assay with an imaging system for live-cell analysis. Using this assay, we successfully discovered potent anti-MerTK Abs that block tumor-associated macrophage-mediated efferocytosis in mice. Furthermore, we used primary human and cynomolgus monkey macrophages to identify and characterize anti-MerTK Abs for potential clinical development. By studying the phagocytic activities of different types of macrophages, we demonstrated that our efferocytosis assay is robust for screening and characterization of drug candidates that inhibit unwanted efferocytosis. Moreover, our assay is also applicable to investigating the kinetics and molecular mechanisms of efferocytosis/phagocytosis.


Asunto(s)
Apoptosis , Neoplasias , Ratones , Humanos , Animales , Tirosina Quinasa c-Mer , Macaca fascicularis , Fagocitosis , Macrófagos , Neoplasias/patología
3.
Environ Monit Assess ; 196(4): 387, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38509267

RESUMEN

The district of Arauca is the second-largest producer of cacao in Colombia. However, despite its quality, it faces issues for export due to levels of cadmium (Cd) higher than the regulatory thresholds. A central question is how it may impact agricultural performance in the presence of Cd in cacao and chocolates. This study quantified Cd in cacao plantations from Arauca. Thus, 180 farms were assessed in the municipalities of Arauquita, Fortul, Saravena, and Tame. Five sample types (soil, irrigation channel sediment, soil litter, cacao seeds, and chocolates) were assessed for Cd. As a technological innovation, the new MXRF technology was used for Cd in chocolates. The sequence of Cd content was soil litter > chocolate > soils > cacao seeds > irrigation-channel sediment. A gradient north-south of Cd content in soil was observed, where highest content was found in farms near the Arauca River, and lower farther away. In irrigation channel sediment, Cd levels averaged 0.07 mg kg-1. The Cd content in cacao seeds was 0.78 mg kg-1 on average. Cd content in chocolates was above the threshold (1.10 mg kg-1 on average, including several cacao mass percentages). These artisanal chocolate bars produced by single farms were near the limit of Cd set by the European Union (up to 0.8 mg kg-1). Therefore, mixing beans from different farms could reduce their Cd content. The present study underscores the complexity of Cd distribution, emphasizing the importance of integrating soil, crop, and landscape features in managing and mitigating Cd levels in cacao.


Asunto(s)
Cacao , Contaminantes del Suelo , Cadmio/análisis , Colombia , Monitoreo del Ambiente , Contaminantes del Suelo/análisis , Suelo , Productos Agrícolas
4.
Bioconjug Chem ; 33(10): 1837-1851, 2022 10 19.
Artículo en Inglés | MEDLINE | ID: mdl-36153839

RESUMEN

Here, we explore whether PEGylation of antibodies can modulate their biodistribution to the eye, an organ once thought to be immune privileged but has recently been shown to be accessible to IV-administered large molecules, such as antibodies. We chose to PEGylate an anti-MerTK antibody, a target with known potential for ocular toxicity, to minimize biodistribution to retinal pigment epithelial cells (RPEs) in the eye by increasing the hydrodynamic volume of the antibody. We used site-specific conjugation to an engineered cysteine on anti-MerTK antibody to chemically attach 40-kDa branched or linear PEG polymers. Despite reduced binding to MerTK on cells, site-specifically PEGylated anti-MerTK retained similar potency in inhibiting MerTK-mediated macrophage efferocytosis of apoptotic cells. Importantly, we found that PEGylation of anti-MerTK significantly reduced MerTK receptor occupancy in RPE cells in both naïve mice and MC-38 tumor-bearing mice, with the branched PEG exhibiting a greater effect than linear PEG. Furthermore, similar to unconjugated anti-MerTK, PEGylated anti-MerTK antibody triggered type I IFN response and exhibited antitumor effect in syngeneic mouse tumor studies. Our results demonstrate the potential of PEGylation to control ocular biodistribution of antibodies.


Asunto(s)
Cisteína , Neoplasias , Ratones , Animales , Tirosina Quinasa c-Mer/metabolismo , Distribución Tisular , Cisteína/metabolismo , Fagocitosis/fisiología , Anticuerpos/metabolismo , Neoplasias/metabolismo , Polietilenglicoles/química , Polímeros/metabolismo , Pigmentos Retinianos/metabolismo
5.
Crit Rev Food Sci Nutr ; 60(11): 1922-1937, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31161778

RESUMEN

Phytoestrogens (PE) are compounds found in plants such as soy (isoflavones), flax seeds and cereals (lignans) and pomegranates (ellagitannins). PE have shown estrogenic/antiestrogenic, antioxidant, anti-inflammatory, antineoplastic and apoptotic activities. The human studies are showing promising although inconsistent results about the beneficial effects of PE on ameliorating the menopausal symptoms or reducing the risk of certain cancers, cardiovascular disease or diabetes. The effects of PE on the organism are mediated by the intestinal microbiota, which transforms them into bioactive PE such as genistein, equol, enterolignans and certain urolithins. In this work, we review the most recent findings about the bacteria able to metabolize PE, together with the latest studies on the effects of PE on health. In addition, we describe the possible factors hindering the demonstration of the beneficial effect of PE on health, evincing the importance of measuring the actual circulating PE in order to encompass the variability of PE metabolism due to the intestinal microbiota. With this in mind, we also explore an approach to ensure the access to bioactive PE.


Asunto(s)
Bacterias/metabolismo , Microbioma Gastrointestinal , Fitoestrógenos/metabolismo , Equol , Genisteína , Humanos , Taninos Hidrolizables , Isoflavonas , Lignanos
6.
Nature ; 505(7482): 239-43, 2014 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-24291791

RESUMEN

The increasing demands placed on natural resources for fuel and food production require that we explore the use of efficient, sustainable feedstocks such as brown macroalgae. The full potential of brown macroalgae as feedstocks for commercial-scale fuel ethanol production, however, requires extensive re-engineering of the alginate and mannitol catabolic pathways in the standard industrial microbe Saccharomyces cerevisiae. Here we present the discovery of an alginate monomer (4-deoxy-L-erythro-5-hexoseulose uronate, or DEHU) transporter from the alginolytic eukaryote Asteromyces cruciatus. The genomic integration and overexpression of the gene encoding this transporter, together with the necessary bacterial alginate and deregulated native mannitol catabolism genes, conferred the ability of an S. cerevisiae strain to efficiently metabolize DEHU and mannitol. When this platform was further adapted to grow on mannitol and DEHU under anaerobic conditions, it was capable of ethanol fermentation from mannitol and DEHU, achieving titres of 4.6% (v/v) (36.2 g l(-1)) and yields up to 83% of the maximum theoretical yield from consumed sugars. These results show that all major sugars in brown macroalgae can be used as feedstocks for biofuels and value-added renewable chemicals in a manner that is comparable to traditional arable-land-based feedstocks.


Asunto(s)
Biocombustibles/provisión & distribución , Metabolismo de los Hidratos de Carbono , Etanol/metabolismo , Ingeniería Genética , Phaeophyceae/metabolismo , Saccharomyces cerevisiae/metabolismo , Alginatos/metabolismo , Anaerobiosis , Ascomicetos/genética , Ascomicetos/metabolismo , Biotecnología , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Evolución Molecular , Fermentación , Prueba de Complementación Genética , Ácido Glucurónico/metabolismo , Ácidos Hexurónicos/metabolismo , Manitol/metabolismo , Phaeophyceae/genética , Ácido Quínico/metabolismo , Reproducibilidad de los Resultados , Saccharomyces cerevisiae/genética , Algas Marinas/genética , Algas Marinas/metabolismo , Ácidos Urónicos/metabolismo
7.
Food Microbiol ; 92: 103581, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32950165

RESUMEN

The majority of cases of listeriosis are associated with the consumption of contaminated food. Some strains of Listeria monocytogenes can persist over months or years in meat processing plants increasing the risk of product contamination. The presence of L. monocytogenes was examined in 10 dry-cured ham processing facilities. A total of 1801 samples were collected from environment and equipment, during processing (1095) and after cleaning and disinfection (706). These samples were taken from non-food contact (736) and food contact (1065) surfaces. In addition, 204 samples from ham surfaces were also analysed. Prevalence varied from 6% to 34% among facilities, and was higher during processing than after cleaning and disinfection (24.8% vs 11.0%) and from non-food than from food contact surfaces (22.6% vs 17.4%). L. monocytogenes serotype 1/2a was predominant (53.9%), followed by 1/2c (26.0%) and 1/2b (15.3%) and less frequently 4b (4.8%). A total of 142 different pulsotypes were registered. Potential persistent L.monocytogenes strains were isolated in 9 out the 10 facilities, with no more than 6 pulsotypes in a given plant. Two pulsotypes were common in different installations, detected before and after cleaning and disinfection, highlighting the importance of monitoring the presence of this pathogen in dry-cured ham processing environments.


Asunto(s)
Manipulación de Alimentos/instrumentación , Listeria monocytogenes/aislamiento & purificación , Productos de la Carne/microbiología , Animales , Contaminación de Equipos , Contaminación de Alimentos/análisis , Microbiología de Alimentos , Listeria monocytogenes/clasificación , Listeria monocytogenes/genética , Productos de la Carne/análisis , Carne de Cerdo/análisis , Carne de Cerdo/microbiología , Porcinos
8.
Rev Invest Clin ; 72(3): 159-164, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32584322

RESUMEN

BACKGROUND: The ideal treatment of coronavirus disease (COVID)-19 has yet to be defined, but convalescent plasma (CoPla) has been successfully employed. OBJECTIVE: The objective of the study was to study the safety and outcomes of the administration of CoPla to individuals with severe COVID-19 in an academic medical center. METHODS: Ten patients were prospectively treated with plasma from COVID-19 convalescent donors. RESULTS: Over 8 days, the sequential organ failure assessment score dropped significantly in all patients, from 3 to 1.5 (p = 0.014); the Kirby index (PaO2/FiO2) score increased from 124 to 255, (p < 0.0001), body temperature decreased significantly from 38.1 to 36.9°C (p = 0.0058), and ferritin levels also dropped significantly from 1736.6 to 1061.8 ng/ml (p = 0.0001). Chest X-rays improved in 7/10 cases and in 6/10, computerized tomography scans also revealed improvement of the lung injury. Decreases in C-reactive protein and D-dimer levels were also observed. Three of five patients on mechanical ventilation support could be extubated, nine were transferred to conventional hospital floors, and six were sent home; two patients died. The administration of CoPla had no side effects and the 24-day overall survival was 77%. CONCLUSIONS: Although other treatments were also administered to the patients and as a result data are difficult to interpret, it seems that the addition of CoPla improved pulmonary function.


Asunto(s)
Betacoronavirus , Infecciones por Coronavirus/terapia , Neumonía Viral/terapia , Adulto , Anciano , Anticuerpos Antivirales/sangre , Betacoronavirus/inmunología , Betacoronavirus/aislamiento & purificación , Biomarcadores , Temperatura Corporal , Proteína C-Reactiva/análisis , COVID-19 , Terapia Combinada , Convalecencia , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/diagnóstico por imagen , Infecciones por Coronavirus/tratamiento farmacológico , Femenino , Ferritinas/sangre , Humanos , Inmunización Pasiva , Estimación de Kaplan-Meier , Pulmón/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Pandemias , Proyectos Piloto , Plasma , Neumonía Viral/sangre , Neumonía Viral/diagnóstico por imagen , Neumonía Viral/tratamiento farmacológico , Estudios Prospectivos , Respiración Artificial , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Adulto Joven , Tratamiento Farmacológico de COVID-19 , Sueroterapia para COVID-19
9.
Appl Microbiol Biotechnol ; 103(9): 3819-3827, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30887172

RESUMEN

Bioengineering of probiotics allows the improvement of their beneficial characteristics. In this work, we develop a molecular tool that would allow the activation of desirable traits in probiotics once they reach the intestine. The activity of upstream regions of bile-inducible genes of Lactobacillus casei BL23 and Lactobacillus plantarum WCFS1 was analyzed using plasmids encoding an anaerobic fluorescent protein as reporter. The promoter P16090 from Lb. casei BL23 was selected and its bile induction confirmed in Lb. casei BL23, Lb. plantarum WCFS1, and in Lactobacillus rhamnosus and Lactobacillus reuteri strains. However, the induction did not occur in Lactococcus lactis MG1363 or Bifidobacterium strains. Studies with different bile compounds revealed the importance of cholic acid in the bile induction process. Induction of fluorescence was also confirmed for transformed Lb. casei BL23 under simulated colonic conditions and in the presence of intestinal microbiota. The developed vector, pNZ:16090-aFP, constitutes a promising tool suitable for the expression of genes of interest under intestinal conditions in probiotic strains of the species Lb. casei, Lb. plantarum, Lb. rhamnosus, and Lb. reuteri.


Asunto(s)
Bilis/metabolismo , Regulación Bacteriana de la Expresión Génica , Lacticaseibacillus casei/genética , Lacticaseibacillus rhamnosus/genética , Lactobacillus plantarum/genética , Humanos , Intestinos/microbiología , Lacticaseibacillus casei/metabolismo , Lactobacillus plantarum/metabolismo , Lacticaseibacillus rhamnosus/metabolismo , Probióticos/análisis , Probióticos/metabolismo , Regiones Promotoras Genéticas
10.
Food Microbiol ; 55: 112-22, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26742622

RESUMEN

Acetic acid bacteria (AAB) are widespread microorganisms in nature, extensively used in food industry to transform alcohols and sugar alcohols into their corresponding organic acids. Specialized strains are used in the production of vinegar through the oxidative transformation of ethanol into acetic acid. The main AAB involved in the production of high-acid vinegars using the submerged fermentation method belong to the genus Komagataeibacter, characterized by their higher ADH stability and activity, and higher acetic acid resistance (15-20%), compared to other AAB. In this work, the bacteria involved in the production of high-acid spirit vinegar through a spontaneous acetic acid fermentation process was studied. The analysis using a culture-independent approach revealed a homogeneous bacterial population involved in the process, identified as Komagataeibacter spp. Differentially expressed proteins during acetic acid fermentation were investigated by using 2D-DIGE and mass spectrometry. Most of these proteins were functionally related to stress response, the TCA cycle and different metabolic processes. In addition, scanning and transmission electron microscopy and specific staining of polysaccharide SDS-PAGE gels confirmed that Komagataeibacter spp. lacked the characteristic polysaccharide layer surrounding the outer membrane that has been previously reported to have an important role in acetic acid resistance in the genus Acetobacter.


Asunto(s)
Ácido Acético/metabolismo , Bebidas Alcohólicas/microbiología , Alphaproteobacteria/metabolismo , Proteínas Bacterianas/química , Alphaproteobacteria/clasificación , Alphaproteobacteria/genética , Alphaproteobacteria/ultraestructura , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Electroforesis en Gel de Poliacrilamida , Fermentación , Datos de Secuencia Molecular , Filogenia , Proteómica
11.
Arch Microbiol ; 197(1): 65-77, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25381572

RESUMEN

The oxalate-carbonate pathway (OCP) is a biogeochemical set of reactions that involves the conversion of atmospheric CO2 fixed by plants into biomass and, after the biological recycling of calcium oxalate by fungi and bacteria, into calcium carbonate in terrestrial environments. Oxalotrophic bacteria are a key element of this process because of their ability to oxidize calcium oxalate. However, the diversity and alternative carbon sources of oxalotrophs participating to this pathway are unknown. Therefore, the aim of this study was to characterize oxalotrophic bacteria in tropical OCP systems from Bolivia, India, and Cameroon. Ninety-five oxalotrophic strains were isolated and identified by sequencing of the 16S rRNA gene. Four genera corresponded to newly reported oxalotrophs (Afipia, Polaromonas, Humihabitans, and Psychrobacillus). Ten strains were selected to perform a more detailed characterization. Kinetic curves and microcalorimetry analyses showed that Variovorax soli C18 has the highest oxalate consumption rate with 0.240 µM h(-1). Moreover, Streptomyces achromogenes A9 displays the highest metabolic plasticity. This study highlights the phylogenetic and physiological diversity of oxalotrophic bacteria in tropical soils under the influence of the oxalate-carbonate pathway.


Asunto(s)
Ecosistema , Bacterias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Oxalatos/metabolismo , Microbiología del Suelo , Biomasa , Bolivia , Oxalato de Calcio/metabolismo , Camerún , Carbono/metabolismo , Genes de ARNr , Bacterias Gramnegativas/clasificación , Bacterias Gramnegativas/genética , Bacterias Gramnegativas/fisiología , Bacterias Grampositivas/clasificación , Bacterias Grampositivas/genética , Bacterias Grampositivas/fisiología , India , Cinética , Ácido Oxálico/metabolismo , Filogenia , Plantas/metabolismo , ARN Ribosómico 16S/genética , Suelo/química , Streptomyces/genética , Clima Tropical
12.
Acta Haematol ; 134(2): 119-24, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25925695

RESUMEN

Admission to the intensive care unit (ICU) of a patient who has been grafted with hematopoietic stem cells is a serious event, but the role of the ICU in this setting remains controversial. Data were analyzed from patients who underwent autologous or allogeneic bone marrow transplantation at the Centro de Hematología y Medicina Interna de Puebla, México, between May 1993 and October 2014. In total, 339 patients were grafted: 150 autografts and 189 allografts; 68 of the grafted patients (20%) were admitted to the ICU after transplantation: 27% of the allografted and 11% of the autografted patients (p = 0.2). Two of 17 autografted patients (12%) and 5 of 51 allografted patients (10%) survived. All patients who required insertion of an endotracheal tube died, whereas 7 of 11 patients without invasive mechanical ventilation survived (p = 0.001). Only 10% of the grafted patients survived their stay in the ICU; this figure is lower than those reported from other centers and may reflect several facts, varying from the quality of the ICU support to ICU admission criteria to the initial management of all the grafts in an outpatient setting, which could somehow delay the arrival of patients to the hospital.


Asunto(s)
Enfermedad Injerto contra Huésped/diagnóstico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Insuficiencia Respiratoria/diagnóstico , Sepsis/diagnóstico , Adolescente , Adulto , Femenino , Enfermedad Injerto contra Huésped/epidemiología , Enfermedad Injerto contra Huésped/etiología , Enfermedad Injerto contra Huésped/terapia , Hospitales Universitarios , Humanos , Lactante , Unidades de Cuidados Intensivos , Masculino , México/epidemiología , Persona de Mediana Edad , Servicio Ambulatorio en Hospital , Pronóstico , Insuficiencia Respiratoria/epidemiología , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/terapia , Riesgo , Sepsis/epidemiología , Sepsis/etiología , Sepsis/terapia , Análisis de Supervivencia , Trasplante Autólogo/efectos adversos , Trasplante Homólogo/efectos adversos
13.
Food Microbiol ; 41: 27-32, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24750810

RESUMEN

The effect of high hydrostatic pressure (HHP) treatments in combination with the lactoperoxidase system (LPOS) or activated lactoferrin (ALF) on Listeria monocytogenes, Salmonella enterica subsp. enterica serovar Enteritidis and Escherichia coli O157:H7 was investigated in cured beef carpaccio stored at 8 °C or 22 °C during 7 d. HHP (450 MPa for 5 min) reduced pathogen levels by 1-3 log units and the antimicrobial effect remained during 7 d of storage under temperature abuse conditions at 8 °C and at 22 °C. The individual application of LPOS and ALF did not affect the survival of the three pathogens studied during storage. However, a synergistic bactericidal interaction between LPOS and HHP was observed against S. Enteritidis and E. coli O157:H7. Combined treatments of HHP with LPOS would be useful to reduce the intensity of pressurization treatments diminishing changes in the quality of meat products.


Asunto(s)
Escherichia coli/crecimiento & desarrollo , Conservación de Alimentos/métodos , Listeria monocytogenes/crecimiento & desarrollo , Productos de la Carne/microbiología , Salmonella enteritidis/crecimiento & desarrollo , Animales , Bovinos , Recuento de Colonia Microbiana , Escherichia coli/química , Conservantes de Alimentos/química , Almacenamiento de Alimentos , Presión Hidrostática , Lactoferrina/química , Lactoperoxidasa/química , Listeria monocytogenes/química , Productos de la Carne/análisis , Viabilidad Microbiana , Salmonella enteritidis/química
14.
Microbiol Spectr ; 12(7): e0336323, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38814085

RESUMEN

Assessing the bacterial community composition across cacao crops is important to understand its potential role as a modulator of cadmium (Cd) translocation to plant tissues under field conditions; Cd mobility between soil and plants is a complex and multifactorial problem that cannot be captured only by experimentation. Although microbes have been shown to metabolize and drive the speciation of Cd under controlled conditions, regardless of the link between soil bacterial community (SBC) dynamics and Cd mobilization in the rhizosphere, only a few studies have addressed the relationship between soil bacterial community composition (SBCC) and Cd content in cacao seeds (Cdseed). Therefore, this study aimed to explore the association between SBCC and different factors influencing the distribution of Cd across cacao crop systems. This study comprised 225 samples collected across five farms, where we used an amplicon sequencing approach to characterize the bacterial community composition. The soil Cd concentration alone (Cdsoil) was a poor predictor of Cdseed. Still, we found that this relationship was more apparent when the variation within farms was controlled, suggesting a role of heterogeneity within farms in modulating Cd translocation and, thus, seed Cd content. Our results provide evidence of the link between soil bacterial communities and the distribution of Cd across Colombian cacao crops, and highlight the importance of incorporating fine-spatial-scale studies to advance the understanding of factors driving Cd uptake and accumulation in cacao plants. IMPORTANCE: Cadmium (Cd) content in cacao crops is an issue that generates interest due to the commercialization of chocolate for human consumption. Several studies provided evidence about the non-biological factors involved in its translocation into the cacao plant. However, factors related to this process, including soil bacterial community composition (SBCC), still need to be addressed. It is well known that soil microbiome could impact compounds' chemical transformation, including Cd, on the field. Here, we found the first evidence of the link between soil bacterial community composition and Cd concentration in cacao soils and seeds. It highlights the importance of including the variation of bacterial communities to assess the factors driving the Cd translocation into cacao seeds. Moreover, the results highlight the relevance of the spatial heterogeneity within and across cacao farms, influencing the variability of Cd concentrations.


Asunto(s)
Bacterias , Cacao , Cadmio , Productos Agrícolas , Microbiota , Rizosfera , Semillas , Microbiología del Suelo , Contaminantes del Suelo , Cadmio/metabolismo , Cadmio/análisis , Cacao/microbiología , Cacao/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/metabolismo , Bacterias/aislamiento & purificación , Contaminantes del Suelo/metabolismo , Contaminantes del Suelo/análisis , Colombia , Productos Agrícolas/microbiología , Productos Agrícolas/metabolismo , Semillas/microbiología , Semillas/metabolismo , Suelo/química
15.
Cureus ; 16(1): e51668, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38313953

RESUMEN

Background Low back pain is known to be one of the leading causes of disability among the young and elderly population. Low back pain can stem from multiple sources, including spinal degeneration, injury, herniated discs, sciatica, and other contributing causes. This symptom significantly influences the quality of life of affected individuals. Its implications include extensive social and economic costs. Economic considerations arise from the fact that not all healthcare facilities accept the insurance plans available to retired individuals under Medicare. This places an additional burden on patients who must bear the financial responsibility for healthcare services not covered by their insurance plan. Florida, renowned as a favored state for retirement, consists of a demographic composition wherein 21% of its residents are aged 65 or older. A significant proportion of this demographic qualifies for Traditional Medicare (TM) and/or Medicare Advantage (MA) plans. Thus, understanding the disparities in healthcare access between Medicare and Medicare Advantage plans is crucial. This study aims to evaluate different Medicare insurances available in the market and their impact on the ease of accessibility to pain management specialists for the treatment of lower back pain in Florida patients. Methods We analyzed the Florida Department of Health database to identify the four counties in Florida with the highest Medicare enrollment rates in 2022: Miami-Dade, Palm Beach, Broward, and Pinellas County. Using the U.S. News and Report directory, 25 Pain Management-trained anesthesiologists were randomly selected from each of the four counties. Each office was contacted four times via telephone by four different team members to assess appointment availability for a fictional 65-year-old grandfather seeking treatment for chronic low back pain. The study examined appointment availability and accepted insurance types, including Cigna (commercial insurance), TM, Humana Gold Plus HMO (Medicare Advantage plan), and Blue Medicare Select PPO (Medicare Advantage plan). Practices without contact information or retired physicians were excluded from the analysis. Time to appointment was measured in business days. Results Of the 100 Pain Management Physicians contacted, 44 fit the inclusion criteria of being non-retired physicians, still practicing in one of the four counties with open offices and valid contact information. Blue Medicare Select PPO was accepted by 47.73%, Humana Gold Plus HMO by 56.82%, TM by 93.18%, and Cigna by 93.18% of the encounters. Blue Medicare select PPO and Humana Gold Plus HMO were accepted at significantly lower rates when compared to Traditional Medicare and Cigna with P values of P < .00001 and P < .000176, respectively. There was no significant difference found in the time to appointment between insurances with P value < 7. Conclusion The study found that patients enrolled in Medicare Advantage plans have significantly decreased access to care when compared to those enrolled in TM or commercial insurance. Further research is needed to elucidate the reasons behind differences in access to care across different insurances, as identified in the study.

16.
Foods ; 12(11)2023 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-37297406

RESUMEN

The presence of Staphylococcus aureus in six dry-cured meat-processing facilities was investigated. S. aureus was detected in 3.8% of surfaces from five facilities. The occurrence was clearly higher during processing (4.8%) than after cleaning and disinfection (1.4%). Thirty-eight isolates were typified by PFGE and MLST. Eleven sequence types (STs) were defined by MLST. ST30 (32%) and ST12 (24%) were the most abundant. Enterotoxin genes were detected in 53% of isolates. The enterotoxin A gene (sea) was present in all ST30 isolates, seb in one ST1 isolate, and sec in two ST45 isolates. Sixteen isolates harbored the enterotoxin gene cluster (egc) with four variations in the sequence. The toxic shock syndrome toxin gene (tst) was detected in 82% of isolates. Regarding antimicrobial resistance, twelve strains were susceptible to all the antibiotics tested (31.6%). However, 15.8% were resistant to three or more antimicrobials and, therefore, multidrug-resistant. Our results showed that in general, efficient cleaning and disinfection procedures were applied. Nonetheless, the presence of S. aureus with virulence determinants and resistance to antimicrobials, particularly multidrug-resistant MRSA ST398 strains, might represent a potential health hazard for consumers.

17.
Br J Pharmacol ; 2023 Oct 02.
Artículo en Inglés | MEDLINE | ID: mdl-37783572

RESUMEN

BACKGROUND AND PURPOSE: Monoclonal antibodies (Ab) represent the fastest growing drug class. Knowledge of the biophysical parameters (kon , koff and KD ) that dictate Ab:receptor interaction is critical during the drug discovery process. However, with the increasing complexity of Ab formats and their targets, it became apparent that existing technologies present limitations and are not always suitable to determine these parameters. Therefore, novel affinity determination methods represent an unmet assay need. EXPERIMENTAL APPROACH: We developed a pre-equilibrium kinetic exclusion assay using recent mathematical advances to determine the kon , koff and KD of monoclonal Ab:receptor interactions on living cells. The assay is amenable to all human IgG1 and rabbit Abs. KEY RESULTS: Using our novel assay, we demonstrated for several monoclonal Ab:receptor pairs that the calculated kinetic rate constants were comparable with orthogonal methods that were lower throughput or more resource consuming. We ran simulations to predict the critical conditions to improve the performance of the assays. We further showed that this method could successfully be applied to both suspension and adherent cells. Finally, we demonstrated that kon and koff , but not KD , correlate with in vitro potency for a panel of monoclonal Abs. CONCLUSIONS AND IMPLICATIONS: Our novel assay has the potential to systematically probe binding kinetics of monoclonal Abs to cells and can be incorporated in a screening cascade to identify new therapeutic candidates. Wide-spread adoption of pre-equilibrium assays using physiologically relevant systems will lead to a more holistic understanding of how Ab binding kinetics influence their potency.

18.
Biodivers Data J ; 11: e112771, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38078291

RESUMEN

Background: Cacao (Theobromacacao L) is one of the most relevant crops in terms of economy and social rural development in Colombia. Cacao is also an important crop due to its potential to replace illicit crops and it is related to less deforestation and preserves the biodiversity. There are several cacao districts in Colombia, one of these being Arauca. The Department of Arauca is the second largest cocoa producing region in Colombia; however, it is heavily affected by armed conflict. To raise the knowledge and technology available in the region, integrating data on the occurrence of cacao farms with climatic variables becomes a powerful socioeconomic mapping tool for maintaining agrobiodiversity and food security in the region. Consequently, this type of agrodiversity data and agroclimatic approaches help to better manage agrobiodiversity, as in the cacao region of Arauca. These tools are even more relevant in biodiverse regions, such as flooded savannahs and tropical forest ecosystems, which are currently undergoing drastic changes due to agricultural expansion and climate change. One of the knowledge gaps in Colombia´s cacao regions is that there are currently no agroclimatic maps made with a social and scientific approach. This study aimed to provide a database of the spatial distribution of cacao farms in Arauca, as well as agroclimatic maps that identify and locate cacao climate regions in Arauca. We also present a presence-only matrix consisting of twenty-six tree species, or agrobiodiversity, distributed across the study region and specifically associated with the cacao forestry systems in Arauca. New information: We present the first database of both climate and agrobiodiversity data related to cacao farms in Arauca, developed with a research and socioeconomic vision that generated a novel approach for the agroclimatic zoning of cocoa in the Arauca Region and Colombia. Using 1,538 cacao farms at the regional scale, we identified two national and six regional-scale climate and soil regions. The selection at the local scale allowed us to classify 180 cacao farms comprising nine agroclimatic clusters in Arauca. We found twenty-six tree species distributed across the cacao climate zones. This dataset and its related maps also represent the agrobiodiversity of cultivated cacao locally. This is the most complete climate and agrobiodiversity dataset of cacao farms distribution in one of the top cocoa-producing regions in the country. These outputs are crucial because they constitute a baseline for developing research in the biodiversity of agroforestry systems, pests and diseases, pollutant presence, genetics, post-harvest processing and cocoa quality and safety.

19.
Brain Sci ; 13(8)2023 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-37626550

RESUMEN

Pesticides are chemicals used in agricultural fields for the prevention or destruction of pests. Inappropriate use of these substances, as well as handling them without using personal protective equipment, may result in serious health problems such as neurodegenerative diseases and mental disorders. Previous studies have demonstrated the adverse effects of pesticides on brain function. However, some researchers have associated pesticide poisoning with the development of disorders such as dissociative amnesia, multiple personality disorders, and depersonalization disorder. The objective of this work was to perform a bibliographic review of the relationship between pesticide poisoning and the development of dissociative disorders. Previous studies suggest that the duration of pesticide exposure is a major determinant in the development of dissociative diseases and disorders. The information obtained in this review suggests that there is no specific relationship between dissociative disorders and pesticide poisoning. However, these results point to associating the most representative symptoms of dissociative disorder (such as amnesia and memory loss) with pesticide exposure. Based on the bibliographic search, possible mechanisms of action were suggested in an attempt to explain a possible association between exposure to pesticides and the appearance of dissociative disorders.

20.
Environ Microbiol ; 14(11): 2960-70, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22928486

RESUMEN

The oxalate-carbonate pathway involves the oxidation of calcium oxalate to low-magnesium calcite and represents a potential long-term terrestrial sink for atmospheric CO(2). In this pathway, bacterial oxalate degradation is associated with a strong local alkalinization and subsequent carbonate precipitation. In order to test whether this process occurs in soil, the role of bacteria, fungi and calcium oxalate amendments was studied using microcosms. In a model system with sterile soil amended with laboratory cultures of oxalotrophic bacteria and fungi, the addition of calcium oxalate induced a distinct pH shift and led to the final precipitation of calcite. However, the simultaneous presence of bacteria and fungi was essential to drive this pH shift. Growth of both oxalotrophic bacteria and fungi was confirmed by qPCR on the frc (oxalotrophic bacteria) and 16S rRNA genes, and the quantification of ergosterol (active fungal biomass) respectively. The experiment was replicated in microcosms with non-sterilized soil. In this case, the bacterial and fungal contribution to oxalate degradation was evaluated by treatments with specific biocides (cycloheximide and bronopol). Results showed that the autochthonous microflora oxidized calcium oxalate and induced a significant soil alkalinization. Moreover, data confirmed the results from the model soil showing that bacteria are essentially responsible for the pH shift, but require the presence of fungi for their oxalotrophic activity. The combined results highlight that the interaction between bacteria and fungi is essential to drive metabolic processes in complex environments such as soil.


Asunto(s)
Bacterias/metabolismo , Hongos/metabolismo , Microbiología del Suelo , Bacterias/clasificación , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Biomasa , Carbonato de Calcio/metabolismo , Desinfectantes/farmacología , Ergosterol/análisis , Ergosterol/metabolismo , Hongos/efectos de los fármacos , Hongos/crecimiento & desarrollo , Concentración de Iones de Hidrógeno , Oxalatos/metabolismo , ARN Ribosómico 16S/genética , Suelo/química
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