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One of the phytosanitary problems in the cultivation of pepper is the whitefly, begomovirus transmitter. Given the need for alternatives, the objective was to evaluate graft tolerance of Capsicum chinense-Capsicum annuum var. glabriusculum to begomovirus under field conditions. Two creole materials were used for rootstock (amashito and muela) and habanero pepper as graft (criollo and jaguar). The "terminal plectrum" graft was used and six treatments were generated. The whitefly populations, the incidence and severity of the disease were recorded every 10 days, with the latter AUDPC were calculated and apparent infection rate Yfinal. In the production stage, yield, length and diameter of fruits it was determined. At 130 days after transplantation, the population under whitefly, it was quantified in the grafted treatments (muela + habanero jaguar, amashito + habanero jaguar, muela + habanero criollo y amashito + habanero criollo) that ranged from 5.5 to 14.5 insects per plant. The increased incidence and severity of virus was average in habanero jaguar with 100 and 62%. The lowest AUDPC, apparent infection rate and Yfinal were estimated in muela + habanero criollo with 746.6 (% per day), 0.0050 (% per day) and 23.4%, in their order; associated with the genetic strength of the rootstock. The grafts amashito + habanero jaguar, amashito + habanero criollo y muela + habanero criollo showed better agronomic performance and productivity of the crop. [ABSTRACT FROM AUTHOR]

El número de personas que conviven con algún tipo de discapacidad ha ido en aumento en el último siglo. Esta tendencia se asocia al elevado número de pacientes con enfermedades crónicas no transmisibles y al envejecimiento poblacional. Se desarrolló una revisión de documentos, artículos científicos y noticias publicadas en los últimos cinco años para conocer las nuevas tendencias en cuanto a los pacientes mayores de 60 años. El objetivo del presente trabajo es describir la relación entre discapacidad y envejecimiento, sus características particulares y la atención de salud bucal de esta población. Se constató que los pacientes conforme avanza la edad, sufren cambios morfológicos a nivel de sus tejidos y sistemas. Las enfermedades bucales más comunes reportadas son la caries dental, enfermedad periodontal, edentulismo total o parcial y cáncer oral. Las actividades planificadas presentan un aumento en el enfoque de promoción y prevención de salud, así como el rediseño de planes de mantenimiento a largo plazo. Se concluye que el estudio resulta pertinente y necesario para la actualización y preparación de los profesionales de la estomatología en tiempos donde el aumento de la esperanza de vida es una tendencia. El estudio se desarrolla en el año actual como parte de un proyecto de investigación.

El presente trabajo fue realizado en diferentes fincas del trópico seco de Nicaragua. Las experiencias se llevaron a cabo principalmente en los municipios de Estelí, Somoto, Condega, Pueblo Nuevo y Limay, área de cobertura del Proyecto PRONORTE. En esta región se presenta una precipitación pluvial de alrededor de 600 a 900 m con una distribución errática, y una época seca muy marcada y con fuertes deficiencias en la disponibilidad de alimentos para el ganado. Los hornos forrajeros fueron construidos con la participación de los productores, quienes fueron informados de los pormenores de la tecnología a efecto de que la experiencia fuera conducida en calidad de validación. Los costos de kg de materia seca del forraje del horno forrajero fue de $0,05 lo que lo hace asequible a los productores de la región, además de utilizar residuos de las cosechas de granos básicos que de otra manera perderían calidad y cantidad. La aceptabilidad de los hornos forrajeros fue alta (100%) y la adopción alcanzó el 96%, cifras que indican que esta tecnología es apropiada y adaptada a las condiciones socioe-conómicas de los productores de la región seca del norte de Nicaragua.

Amikacin is an FDA-approved aminoglycoside antibiotic that is commonly used. However, validated dosage regimens that achieve clinically relevant exposure profiles in mice are lacking. We aimed to design and validate humanized dosage regimens for amikacin in immune-competent murine bloodstream and lung infection models of Acinetobacter baumannii . Plasma and lung epithelial lining fluid (ELF) concentrations after single subcutaneous doses of 1.37, 13.7, and 137 mg/kg of body weight were simultaneously modeled via population pharmacokinetics. Then, humanized amikacin dosage regimens in mice were designed and prospectively validated to match the peak, area, trough, and range of plasma concentration profiles in critically ill patients (clinical dose: 25-30 mg/kg of body weight). The pharmacokinetics of amikacin were linear, with a clearance of 9.93 mL/h in both infection models after a single dose. However, the volume of distribution differed between models, resulting in an elimination half-life of 48 min for the bloodstream and 36 min for the lung model. The drug exposure in ELF was 72.7% compared to that in plasma. After multiple q6h dosing, clearance decreased by ~80% from the first (7.35 mL/h) to the last two dosing intervals (~1.50 mL/h) in the bloodstream model. Likewise, clearance decreased by 41% from 7.44 to 4.39 mL/h in the lung model. The humanized dosage regimens were 117 mg/kg of body weight/day in mice [administered in four fractions 6 h apart (q6h): 61.9%, 18.6%, 11.3%, and 8.21% of total dose] for the bloodstream and 96.7 mg/kg of body weight/day (given q6h as 65.1%, 16.9%, 10.5%, and 7.41%) for the lung model. These validated humanized dosage regimens and population pharmacokinetic models support translational studies with clinically relevant amikacin exposure profiles., Competing Interests: The authors declare no conflict of interest.

Polymyxin B is a "last-line-of-defense" antibiotic approved in the 1960s. However, the population pharmacokinetics (PK) of its four main components has not been reported in infected mice. We aimed to determine the PK of polymyxin B1, B1-Ile, B2, and B3 in a murine bloodstream and lung infection model of Acinetobacter baumannii and develop humanized dosage regimens. A linear 1-compartment model, plus an epithelial lining fluid (ELF) compartment for the lung model, best described the PK. Clearance and volume of distribution were similar among the four components. The bioavailability fractions were 72.6% for polymyxin B1, 12.0% for B1-Ile, 11.5% for B2, and 3.81% for B3 for the lung model and were similar for the bloodstream model. While the volume of distribution was comparable between both models (17.3 mL for the lung and ~27 mL for the bloodstream model), clearance was considerably smaller for the lung (2.85 mL/h) compared to that of the bloodstream model (5.59 mL/h). The total drug exposure (AUC) in ELF was high due to the saturable binding of polymyxin B presumably to bacterial lipopolysaccharides. However, the modeled unbound AUC in ELF was ~16.7% compared to the total drug AUC in plasma. The long elimination half-life (~4 h) of polymyxin B enabled humanized dosage regimens with every 12 h dosing in mice. Daily doses that optimally matched the range of drug concentrations observed in patients were 21 mg/kg for the bloodstream and 13 mg/kg for the lung model. These dosage regimens and population PK models support translational studies for polymyxin B at clinically relevant drug exposures., Competing Interests: The authors declare no conflict of interest.

Acinetobacter baumannii is an extremely drug-resistant pathogen necessitating the development of new therapies. We seek to generate a cocktail of monoclonal antibodies (MAbs) that can target the full diversity of A. baumannii isolates. We have newly identified the antibody MAb5. Here, we demonstrate that MAb5 has broad binding against U.S. ( n  = 300) and international ( n  = 250) isolates (72.24% and 28.76%, respectively), likely targets O-antigen capsular carbohydrates, and exhibits protective efficacy in vivo .

Novel approaches to combating antibiotic resistance are needed given the ever-continuing rise of antibiotic resistance and the scarce discovery of new antibiotics. Little is known about the colonization dynamics and the role of intrinsic plant-food characteristics in this process. We sought to determine whether plant fiber could alter colonization dynamics by antibiotic-resistant bacteria in the gut. We determined that ingestion of antibiotics in mice markedly enhanced gut colonization by a pathogenic extended-spectrum beta-lactamase-producing Escherichia coli strain of human origin, E. coli JJ1886 (ST131- H 30Rx). Furthermore, ingestion of soluble acacia fiber before and after antibiotic exposure significantly reduced pathogenic E. coli colonization. 16S rRNA analysis and ex vivo cocultures demonstrated that fiber protected the microbiome by serving as a prebiotic, which induced native gut E. coli to inhibit pathogenic E. coli via colicin M. Fiber may be a useful prebiotic with which to administer antibiotics to protect human and livestock gut microbiomes against colonization from antibiotic-resistant, pathogenic bacteria. IMPORTANCE A One Health-based strategy-the concept that human health and animal health are interconnected with the environment-is necessary to determine the drivers of antibiotic resistance from food to the clinic. Moreover, humans can ingest antibiotic-resistant bacteria on food and asymptomatically, or "silently," carry such bacteria in the gut long before they develop an opportunistic extraintestinal infection. Here, we determined that fiber-rich foods, in particular acacia fiber, may be a new, promising, and inexpensive prebiotic to administer with antibiotics to protect the mammalian (i.e., human and livestock) gut against such colonization by antibiotic-resistant, pathogenic bacteria.

Recently, we reported rifabutin hyperactivity against Acinetobacter baumannii We sought to characterize potential interactions between rifabutin and colistin, the last-resort drug for carbapenem-resistant infections. Rifabutin and colistin were synergistic in vitro and in vivo , and low-dose colistin significantly suppressed emergence of resistance to rifabutin. Thus, this combination is a promising therapeutic option for highly resistant A. baumannii infections., (Copyright © 2021 Cheng et al.)

Agricultural use of antibiotics is recognized by the U.S. Centers for Disease Control and Prevention as a major contributor to antibiotic-resistant infections. While most One Health attention has been on the potential for antibiotic resistance transmission from livestock and contaminated meat products to people, plant foods are fundamental to the food chain for meat eaters and vegetarians alike. We hypothesized that environmental bacteria that colonize plant foods may serve as platforms for the persistence of antibiotic-resistant bacteria and for horizontal gene transfer of antibiotic-resistant genes. Donor Acinetobacter baylyi and recipient Escherichia coli were cocultured in vitro , in planta on lettuce, and in vivo in BALB/c mice. We showed that nonpathogenic, environmental A. baylyi is capable of transferring plasmids conferring antibiotic resistance to E. coli clinical isolates on lettuce leaf discs. Furthermore, transformant E. coli from the in planta assay could then colonize the mouse gut microbiome. The target antibiotic resistance plasmid was identified in mouse feces up to 5 days postinfection. We specifically identified in vivo transfer of the plasmid to resident Klebsiella pneumoniae in the mouse gut. Our findings highlight the potential for environmental bacteria exposed to antibiotics to transmit resistance genes to mammalian pathogens during ingestion of leafy greens. IMPORTANCE Previous efforts have correlated antibiotic-fed livestock and meat products with respective antibiotic resistance genes, but virtually no research has been conducted on the transmission of antibiotic resistance from plant foods to the mammalian gut (C. S. Hölzel, J. L. Tetens, and K. Schwaiger, Pathog Dis 15:671-688, 2018, https://doi.org/10.1089/fpd.2018.2501; C. M. Liu et al., mBio 9:e00470-19, 2018, https://doi.org/10.1128/mBio.00470-18; B. Spellberg et al., NAM Perspectives, 2016, https://doi.org/10.31478/201606d; J. O'Neill, Antimicrobials in agriculture and the environment, 2015; Centers for Disease Control and Prevention, Antibiotic resistance threats in the United States, 2019). Here, we sought to determine if horizontal transmission of antibiotic resistance genes can occur between lettuce and the mammalian gut microbiome, using a mouse model. Furthermore, we have created a new model to study horizontal gene transfer on lettuce leaves using an antibiotic-resistant transformant of A. baylyi (Ab zeoR )., (Copyright © 2020 Maeusli et al.)

In 2017, the WHO identified Acinetobacter baumannii as the top priority for the development of new antibiotics. Despite the need for new antibiotics, there remains a lack of well validated preclinical tools for A. baumannii. Here, we characterize and validate a mouse model for A. baumannii translational research. Antibiotic sensitivity for meropenem, amikacin, and polymyxin b was determined by the broth microdilution MIC assay. LD100 inoculums, in both blood and lung infection models, were determined in male and female C3HeB/FeJ mice that were challenged with various A. baumannii clinical isolates. Blood (blood infection model) or blood and lung tissue (lung infection model) were collected from infected mice at 2 and 18 hours and the bacterial burden was determined by quantitative culture. Blood chemistry was analyzed using the iStat system. Cytokines (IL-1ß, TNF, IL-6, and IL-10) were measured in the blood and lung homogenate by ELISA assay. Lung sections (H&E stains) were scored by a pathologist. In the blood infection model, the cytokines and physiological data indicate that mice become moribund due to sepsis (low blood pH, falling bicarbonate, and a rising base deficit), whereas mice become moribund due to respiratory failure (low blood pH, rising bicarbonate, and a falling base deficit) in the oral aspiration pneumonia model. We also characterized the timing of changes in various clinical and biomarker endpoints, which can serve as a basis for future interventional studies. Susceptibility was generally similar across gender and infection route. However, we did observe that female mice were approximately 2-fold more sensitive to LAC-4 ColR in the blood infection model. We also observed that female mice were more than 10-fold more resistant to VA-AB41 in the oral aspiration pneumonia model. These results establish parameters to follow in order to assess efficacy of novel preventative and therapeutic approaches for these infections., Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests: In the last 12 months, author BL has owned equity in Exbaq. In the last 12 months, author BS has consulted for Shionogi, Alexion, Synthetic Biologics, Paratek, TheoremDx, and Acurx, and has owned equity in Motif, BioAIM, Synthetic Biologics, Mycomed, and Exbaq.In the last 12 months, author RB has consulted for Merck, Allergan, Wockhardt, Shionogi, and Entasis. In the last 12 months, TN has owned equity in Exbaq and BioAim. This does not alter our adherence to PLOS ONE policies on sharing data and materials.