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Authors = Katherine Munoz ORCID = 0000-0003-2502-3308

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18 pages, 532 KiB  
Review
Respiratory Muscle Training in Mechanically Ventilated Adult Patients: Toward a Precise Prescription Based on Current Evidence: A Scoping Review
by Jennifer Andrea Carabalí-Rivera, Valeria Salazar-Muñoz, Evelyn dayana Villanueva-Londoño, Katherine González-Ruiz and Leonardo Arzayus-Patiño
J. Clin. Med. 2025, 14(14), 5058; https://doi.org/10.3390/jcm14145058 - 17 Jul 2025
Viewed by 667
Abstract
Respiratory muscle training (RMT) has been proposed as a supportive strategy for adults receiving invasive mechanical ventilation; however, the way RMT is prescribed—mode, intensity, frequency, and volume—remains highly heterogeneous. Objectives: This study aimed to describe the current evidence regarding the prescription of [...] Read more.
Respiratory muscle training (RMT) has been proposed as a supportive strategy for adults receiving invasive mechanical ventilation; however, the way RMT is prescribed—mode, intensity, frequency, and volume—remains highly heterogeneous. Objectives: This study aimed to describe the current evidence regarding the prescription of respiratory muscle strengthening in terms of frequency, intensity, method, and volume in adult patients under mechanical ventilation in intensive care units. Methods: A scoping review was conducted following the PRISMA-ScR guidelines based on searches in electronic databases including Scopus, SciELO, ScienceDirect, PubMed, LILACS, Springer, Web of Science, Google Scholar, PEDro, Dialnet, and Cochrane. Results: Seven studies met the established inclusion criteria and described prescription protocols for respiratory muscle strengthening in adult patients under mechanical ventilation in intensive care units. Conclusions: The most frequently reported protocol involved threshold load training at 40–50% of maximal inspiratory pressure, administered twice daily, every day of the week, with a volume of 30 repetitions. This intervention showed promising results in improving inspiratory muscle strength, with potential additional benefits in weaning success and pulmonary function. Full article
(This article belongs to the Section Respiratory Medicine)
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20 pages, 999 KiB  
Article
Efficient Real-Time Isotope Identification on SoC FPGA
by Katherine Guerrero-Morejón, José María Hinojo-Montero, Jorge Jiménez-Sánchez, Cristian Rocha-Jácome, Ramón González-Carvajal and Fernando Muñoz-Chavero
Sensors 2025, 25(12), 3758; https://doi.org/10.3390/s25123758 - 16 Jun 2025
Viewed by 896
Abstract
Efficient real-time isotope identification is a critical challenge in nuclear spectroscopy, with important applications such as radiation monitoring, nuclear waste management, and medical imaging. This work presents a novel approach for isotope classification using a System-on-Chip FPGA, integrating hardware-accelerated principal component analysis (PCA) [...] Read more.
Efficient real-time isotope identification is a critical challenge in nuclear spectroscopy, with important applications such as radiation monitoring, nuclear waste management, and medical imaging. This work presents a novel approach for isotope classification using a System-on-Chip FPGA, integrating hardware-accelerated principal component analysis (PCA) for feature extraction and a software-based random forest classifier. The system leverages the FPGA’s parallel processing capabilities to implement PCA, reducing the dimensionality of digitized nuclear signals and optimizing computational efficiency. A key feature of the design is its ability to perform real-time classification without storing ADC samples, directly processing nuclear pulse data as it is acquired. The extracted features are classified by a random forest model running on the embedded microprocessor. PCA quantization is applied to minimize power consumption and resource usage without compromising accuracy. The experimental validation was conducted using datasets from high-resolution pulse-shape digitization, including closely matched isotope pairs (12C/13C, 36Ar/40Ar, and 80Kr/84Kr). The results demonstrate that the proposed SoC FPGA system significantly outperforms conventional software-only implementations, reducing latency while maintaining classification accuracy above 98%. This study provides a scalable, precise, and energy-efficient solution for real-time isotope identification. Full article
(This article belongs to the Section Internet of Things)
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14 pages, 2450 KiB  
Article
Assessment of Heterozygosity in European Local and Cosmopolitan Pig Populations
by Maria Chiara Fabbri, Katherine D. Arias, Marcos P. G. Rezende, Francesco Tiezzi, Stefano Biffani, Felix Goyache, Giuseppina Schiavo, Samuele Bovo, Luca Fontanesi, Marjeta Čandek-Potokar, Maria Muñoz, Cristina Ovilo, Klavdija Poklukar, Martin Škrlep and Riccardo Bozzi
Agriculture 2025, 15(7), 761; https://doi.org/10.3390/agriculture15070761 - 1 Apr 2025
Viewed by 565
Abstract
Researchers focused on assessing differences in gene diversity within and between populations, whether cosmopolitan or local. However, the identification of patterns of variation in non-random heterozygous genomic stretches, known as Heterozygosity-Rich regions (HRRs), has not yet been determined in European local pig breeds. [...] Read more.
Researchers focused on assessing differences in gene diversity within and between populations, whether cosmopolitan or local. However, the identification of patterns of variation in non-random heterozygous genomic stretches, known as Heterozygosity-Rich regions (HRRs), has not yet been determined in European local pig breeds. A total of 23 pig breeds (20 local and 3 cosmopolitan) were assessed and compared in terms of heterozygosity-rich regions. The breeds with the highest number of HRRs were Large White, Lithuanian Old type, and Landrace, followed by Lithuanian Native, Mora Romagnola, and Duroc. The breeds with the lowest number were Alentejana, Iberian, and Majorcan Black. No shared HRR islands were found in all breeds, but gene enrichment analysis performed in the most common HRRs revealed several biologically important genes that cluster together and play significant roles, primarily related to the immune system. Permutation analysis indicated that some local breeds serve as true reservoirs of genetic diversity, displaying distinct and unique characteristics in terms of heterozygosity. This study suggests the importance of investigating heterozygosity to develop a comprehensive picture of pig breeds, regardless of the production system, country of origin, or population size. Full article
(This article belongs to the Special Issue Genetic Diversity, Adaptation and Evolution of Livestock)
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14 pages, 2451 KiB  
Article
Inbreeding and Gallbladder Cancer Risk: Homozygosity Associations Adjusted for Indigenous American Ancestry, BMI, and Genetic Risk of Gallstone Disease
by Francisco Ceballos, Felix Boekstegers, Dominique Scherer, Carol Barahona Ponce, Katherine Marcelain, Valentina Gárate-Calderón, Melanie Waldenberger, Erik Morales, Armando Rojas, César Munoz, Javier Retamales, Gonzalo de Toro, Allan Vera Kortmann, Olga Barajas, María Teresa Rivera, Analía Cortés, Denisse Loader, Javiera Saavedra, Lorena Gutiérrez, Alejandro Ortega, Maria Enriqueta Bertrán, Leonardo Bartolotti, Fernando Gabler, Mónica Campos, Juan Alvarado, Fabricio Moisán, Loreto Spencer, Bruno Nervi, Daniel Carvajal-Hausdorf, Héctor Losada, Mauricio Almau, Plinio Fernández, Jordi Olloquequi, Pamela Salinas and Justo Lorenzo Bermejoadd Show full author list remove Hide full author list
Cancers 2024, 16(24), 4195; https://doi.org/10.3390/cancers16244195 - 17 Dec 2024
Viewed by 1521
Abstract
Latin Americans have a rich genetic make-up that translates into heterogeneous fractions of the autosomal genome in runs of homozygosity (FROH) and heterogeneous types and proportions of indigenous American ancestry. While autozygosity has been linked to several human diseases, very little [...] Read more.
Latin Americans have a rich genetic make-up that translates into heterogeneous fractions of the autosomal genome in runs of homozygosity (FROH) and heterogeneous types and proportions of indigenous American ancestry. While autozygosity has been linked to several human diseases, very little is known about the relationship between inbreeding, genetic ancestry, and cancer risk in Latin Americans. Chile has one of the highest incidences of gallbladder cancer (GBC) in the world, and we investigated the association between inbreeding, GBC, gallstone disease (GSD), and body mass index (BMI) in 4029 genetically admixed Chileans. We calculated individual FROH above 1.5 Mb and weighted polygenic risk scores for GSD, and applied multiple logistic regression to assess the association between homozygosity and GBC risk. We found that homozygosity was due to a heterogeneous mixture of genetic drift and consanguinity in the study population. Although we found no association between homozygosity and overall GBC risk, we detected interactions of FROH with sex, age, and genetic risk of GSD that affected GBC risk. Specifically, the increase in GBC risk per 1% FROH was 19% in men (p-value = 0.002), 30% in those under 60 years of age (p-value = 0.001), and 12% in those with a genetic risk of GSD above the median (p-value = 0.01). The present study highlighted the complex interplay between inbreeding, genetic ancestry, and genetic risk of GSD in the development of GBC. The applied methodology and our findings underscored the importance of considering the population-specific genetic architecture, along with sex- and age-specific effects, when investigating the genetic basis of complex traits in Latin Americans. Full article
(This article belongs to the Section Cancer Epidemiology and Prevention)
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11 pages, 3429 KiB  
Article
Study of Chiral Center Effect on CaLB-Catalyzed Hydrolysis of (±)-1-(Acetoxymethyl)-3, 4, 5-methylpyrrolidin-2-ones
by Luis G. Hernández-Vázquez, Grecia Katherine Sánchez-Muñoz and Jaime Escalante
Catalysts 2024, 14(12), 861; https://doi.org/10.3390/catal14120861 - 26 Nov 2024
Viewed by 934
Abstract
Several chemical and biocatalytic methods have been described for chiral γ-lactams syntheses. However, only one biocatalytic method has been reported for γ4-lactam resolution, while γ2- and γ3-lactams have not been reported. On the other hand, its resolution [...] Read more.
Several chemical and biocatalytic methods have been described for chiral γ-lactams syntheses. However, only one biocatalytic method has been reported for γ4-lactam resolution, while γ2- and γ3-lactams have not been reported. On the other hand, its resolution through biocatalysts is complicated since enzymes such as ENZA-1 (Rhodococcus equi NCIB 40213) and ENZA-20 (Pseudomonas solanacearum NCIB 40249) are difficult to obtain. Therefore, in this paper, the resolution of γ-lactams 7-9 was carried out through a hydrolysis reaction using the commercially available enzyme CaLB. Full article
(This article belongs to the Special Issue New Advances in Chemoenzymatic Synthesis, 2nd Edition)
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16 pages, 1571 KiB  
Article
Mitigation of Vibrio-Induced Metabolic Perturbations in Argopecten purpuratus Scallop Larvae via Probiotic Pretreatment
by Katherine Muñoz-Cerro, Leonie Venter, Tim Young, Andrea C. Alfaro, Katherina Brokordt and Paulina Schmitt
J. Mar. Sci. Eng. 2024, 12(7), 1138; https://doi.org/10.3390/jmse12071138 - 6 Jul 2024
Viewed by 1502
Abstract
Background: The decrease in the production of Argopecten purpuratus scallops in Chile is linked to extensive larval deaths in hatcheries caused by bacterial pathogens, particularly Vibrio genus, threatening sustainability. Traditional antibiotic practices raise concerns, urging research on eco-friendly strategies like bacterial probiotics. This [...] Read more.
Background: The decrease in the production of Argopecten purpuratus scallops in Chile is linked to extensive larval deaths in hatcheries caused by bacterial pathogens, particularly Vibrio genus, threatening sustainability. Traditional antibiotic practices raise concerns, urging research on eco-friendly strategies like bacterial probiotics. This study explores the metabolic responses of scallop larvae to Vibrio bivalvicida and evaluates the impact of the Psychrobacter sp. R10_7 probiotic on larval metabolism pre- and post-infection. Materials and Methods: Analysis detected 183 metabolite features, revealing significant changes in larval metabolites during Vibrio infection. Larvae pretreated with probiotics showed a metabolic profile comparable to non-infected larvae, indicating low impact on larval metabolome, likely due to probiotics antagonistic effect on pathogens. Results: Arachidonic acid, eicosatrienoic acid, docosahexaenoic acid (DHA), eicosapentaenoic acid (EPA), and docosapentaenoic acid (DPA) were significantly higher in non-pretreated/infected larvae compared to both pretreated/infected and non-pretreated/non-infected larvae, potentially supporting the activation of immune response in non-pretreated larvae to Vibrio infection. Identification of 76 metabolites provided insights into scallop larvae metabolome, highlighting the enriched metabolic pathways associated with energy provision and immune response. Conclusions: Probiotic pretreatment may mitigate metabolic disruptions in scallop larvae caused by Vibrio infection, suggesting a promising strategy for sustainable scallop production. Full article
(This article belongs to the Section Marine Aquaculture)
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16 pages, 3609 KiB  
Article
Principal Component Analysis Applied to Digital Pulse Shape Analysis for Isotope Discrimination
by Katherine Guerrero-Morejón, José María Hinojo-Montero, Fernando Muñoz-Chavero, Juan Luis Flores-Garrido, Juan Antonio Gómez-Galán and Ramón González-Carvajal
Sensors 2023, 23(23), 9418; https://doi.org/10.3390/s23239418 - 26 Nov 2023
Cited by 2 | Viewed by 1847
Abstract
Digital pulse shape analysis (DPSA) techniques are becoming increasingly important for the study of nuclear reactions since the development of fast digitizers. These techniques allow us to obtain the (A, Z) values of the reaction products impinging on the new generation solid-state detectors. [...] Read more.
Digital pulse shape analysis (DPSA) techniques are becoming increasingly important for the study of nuclear reactions since the development of fast digitizers. These techniques allow us to obtain the (A, Z) values of the reaction products impinging on the new generation solid-state detectors. In this paper, we present a computationally efficient method to discriminate isotopes with similar energy levels, with the aim of enabling the edge-computing paradigm in future field-programmable gate-array-based acquisition systems. The discrimination of isotope pairs with analogous energy levels has been a topic of interest in the literature, leading to various solutions based on statistical features or convolutional neural networks. Leveraging a valuable dataset obtained from experiments conducted by researchers in the FAZIA Collaboration at the CIME cyclotron in GANIL laboratories, we aim to establish a comparative analysis regarding selectivity and computational efficiency, as this dataset has been employed in several prior publications. Specifically, this work presents an approach to discriminate between pairs of isotopes with similar energies, namely, 12,13C, 36,40Ar, and 80,84Kr, using principal component analysis (PCA) for data preprocessing. Consequently, a linear and cubic machine learning (ML) support vector machine (SVM) classification model was trained and tested, achieving a high identification capability, especially in the cubic one. These results offer improved computational efficiency compared to the previously reported methodologies. Full article
(This article belongs to the Special Issue Advances in Particle Detectors and Radiation Detectors)
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16 pages, 354 KiB  
Article
Diet Digestibility and Partitioning of Nutrients in Adult Male Alpacas Fed a Blend of Oat Hay and Alfalfa Pellets at Two Levels of Intake
by Paola Katherine Chipa Guillen, Walter Orestes Antezana Julián, Wilfredo Manuel Rios Rado, Juan Elmer Moscoso-Muñoz and Edward H. Cabezas-Garcia
Animals 2023, 13(23), 3613; https://doi.org/10.3390/ani13233613 - 22 Nov 2023
Cited by 1 | Viewed by 1948
Abstract
Alpacas are well adapted to consume the poor-quality forages present in the arid conditions of the Andean Altiplano. However, studies focusing on understanding the relationship between diet digestibility and intake are scarce. The aim of this study was to evaluate the effects of [...] Read more.
Alpacas are well adapted to consume the poor-quality forages present in the arid conditions of the Andean Altiplano. However, studies focusing on understanding the relationship between diet digestibility and intake are scarce. The aim of this study was to evaluate the effects of two levels of dry matter intake (DMI) on a metabolic body weight (BW0.75) basis. The effects of a maintenance level of intake and an ad libitum level of intake (40 and 50 g of dry matter (DM) per kg of BW0.75, respectively) on the apparent diet digestibility and partitioning of specific nutrients (energy, carbon (C), and nitrogen (N)) of alpacas that were fed a blend of oat hay and alfalfa pellets (70:30 ratio as a percentage on a fed basis) were evaluated. Five adult intact male alpacas (BW = 62.9 ± 8.09 kg at the beginning of the study) were fed with the experimental diet and trained to be allocated in metabolism crates for 30 days. After the completion of this phase, two separate experiments for each level of intake were carried out, each lasting for twenty-six days (with the final five days taken for samples and raw data collection). In both experiments, the animals responded differently in terms of nutrient supply and changes in BW (−140 and 100 g/d for the maintenance and ad libitum levels of intake, respectively). Oat hay consumption was rather similar in both experiments, which may be explained by a reduced ingredient selectivity at the ad libitum level of intake. Diet digestibility was similar in both experiments, despite the greater fecal output of nutrients with the increased level of diet intake. In line with this, diet metabolizability, calculated as the ratio between metabolizable energy (ME) and gross energy (GE) contents, indicated a similar energy utilization of the diet. The apparent digestibility of the organic matter (OMD) ranged from 655 to 669 g/kg DM. Water consumption at the ad libitum level of intake was 21% higher than the observed mean at the maintenance level of intake. Fecal outputs of dietary energy, C, and N accounted for the largest source of excreted nutrients, regardless of the level of intake. The N retention increased from 0.439 at the maintenance level of intake, to 0.473 g of DM/kg BW0.75 when the alpacas were fed ad libitum. Full article
(This article belongs to the Section Animal Nutrition)
13 pages, 1629 KiB  
Article
Identification of Unique microRNA Profiles in Different Types of Idiopathic Inflammatory Myopathy
by Sandra Muñoz-Braceras, Iago Pinal-Fernandez, Maria Casal-Dominguez, Katherine Pak, José César Milisenda, Shajia Lu, Massimo Gadina, Faiza Naz, Gustavo Gutierrez-Cruz, Stefania Dell’Orso, Jiram Torres-Ruiz, Josep Maria Grau-Junyent, Albert Selva-O’Callaghan, Julie J. Paik, Jemima Albayda, Lisa Christopher-Stine, Thomas E. Lloyd, Andrea M. Corse and Andrew L. Mammen
Cells 2023, 12(17), 2198; https://doi.org/10.3390/cells12172198 - 2 Sep 2023
Cited by 9 | Viewed by 2692
Abstract
Dermatomyositis (DM), antisynthetase syndrome (AS), immune-mediated necrotizing myopathy (IMNM), and inclusion body myositis (IBM) are four major types of idiopathic inflammatory myopathy (IIM). Muscle biopsies from each type of IIM have unique transcriptomic profiles. MicroRNAs (miRNAs) target messenger RNAs (mRNAs), thereby regulating their [...] Read more.
Dermatomyositis (DM), antisynthetase syndrome (AS), immune-mediated necrotizing myopathy (IMNM), and inclusion body myositis (IBM) are four major types of idiopathic inflammatory myopathy (IIM). Muscle biopsies from each type of IIM have unique transcriptomic profiles. MicroRNAs (miRNAs) target messenger RNAs (mRNAs), thereby regulating their expression and modulating transcriptomic profiles. In this study, 18 DM, 12 IMNM, 6 AS, 6 IBM, and 6 histologically normal muscle biopsies underwent miRNA profiling using the NanoString nCounter system. Eleven miRNAs were exclusively differentially expressed in DM compared to controls, seven miRNAs were only differentially expressed in AS, and nine miRNAs were specifically upregulated in IBM. No differentially expressed miRNAs were identified in IMNM. We also analyzed miRNA-mRNA associations to identify putative targets of differentially expressed miRNAs. In DM and AS, these were predominantly related to inflammation and cell cycle progression. Moreover, our analysis showed an association between miR-30a-3p, miR-30e-3p, and miR-199b-5p downregulation in DM and the upregulation of target genes induced by type I interferon. In conclusion, we show that muscle biopsies from DM, AS, and IBM patients have unique miRNA signatures and that these miRNAs might play a role in regulating the expression of genes known to be involved in IIM pathogenesis. Full article
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17 pages, 1740 KiB  
Article
Gallbladder Cancer Risk and Indigenous South American Mapuche Ancestry: Instrumental Variable Analysis Using Ancestry-Informative Markers
by Linda Zollner, Felix Boekstegers, Carol Barahona Ponce, Dominique Scherer, Katherine Marcelain, Valentina Gárate-Calderón, Melanie Waldenberger, Erik Morales, Armando Rojas, César Munoz, Javier Retamales, Gonzalo De Toro, Allan Vera Kortmann, Olga Barajas, María Teresa Rivera, Analía Cortés, Denisse Loader, Javiera Saavedra, Lorena Gutiérrez, Alejandro Ortega, Maria Enriqueta Bertrán, Leonardo Bartolotti, Fernando Gabler, Mónica Campos, Juan Alvarado, Fabricio Moisán, Loreto Spencer, Bruno Nervi, Daniel Carvajal, Héctor Losada, Mauricio Almau, Plinio Fernández, Jordi Olloquequi, Alice R. Carter, Juan Francisco Miquel Poblete, Bernabe Ignacio Bustos, Macarena Fuentes Guajardo, Rolando Gonzalez-Jose, Maria Cátira Bortolini, Victor Acuña-Alonzo, Carla Gallo, Andres Ruiz Linares, Francisco Rothhammer and Justo Lorenzo Bermejoadd Show full author list remove Hide full author list
Cancers 2023, 15(16), 4033; https://doi.org/10.3390/cancers15164033 - 9 Aug 2023
Cited by 12 | Viewed by 9411
Abstract
A strong association between the proportion of indigenous South American Mapuche ancestry and the risk of gallbladder cancer (GBC) has been reported in observational studies. Chileans show the highest incidence of GBC worldwide, and the Mapuche are the largest indigenous people in Chile. [...] Read more.
A strong association between the proportion of indigenous South American Mapuche ancestry and the risk of gallbladder cancer (GBC) has been reported in observational studies. Chileans show the highest incidence of GBC worldwide, and the Mapuche are the largest indigenous people in Chile. We set out to assess the confounding-free effect of the individual proportion of Mapuche ancestry on GBC risk and to investigate the mediating effects of gallstone disease and body mass index (BMI) on this association. Genetic markers of Mapuche ancestry were selected based on the informativeness for assignment measure, and then used as instrumental variables in two-sample Mendelian randomization analyses and complementary sensitivity analyses. Results suggested a putatively causal effect of Mapuche ancestry on GBC risk (inverse variance-weighted (IVW) risk increase of 0.8% per 1% increase in Mapuche ancestry proportion, 95% CI 0.4% to 1.2%, p = 6.7 × 10−5) and also on gallstone disease (3.6% IVW risk increase, 95% CI 3.1% to 4.0%), pointing to a mediating effect of gallstones on the association between Mapuche ancestry and GBC. In contrast, the proportion of Mapuche ancestry showed a negative effect on BMI (IVW estimate −0.006 kg/m2, 95% CI −0.009 to −0.003). The results presented here may have significant implications for GBC prevention and are important for future admixture mapping studies. Given that the association between the individual proportion of Mapuche ancestry and GBC risk previously noted in observational studies appears to be free of confounding, primary and secondary prevention strategies that consider genetic ancestry could be particularly efficient. Full article
(This article belongs to the Collection Advances in Cancer Disparities)
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15 pages, 4827 KiB  
Article
Nicotinamide Prevents Diabetic Brain Inflammation via NAD+-Dependent Deacetylation Mechanisms
by Jeimy Katherine Torres-Méndez, Julia Niño-Narvión, Patricia Martinez-Santos, Elena María Goretti Diarte-Añazco, Karen Alejandra Méndez-Lara, Tania Vázquez del Olmo, Noemi Rotllan, Maria Teresa Julián, Núria Alonso, Didac Mauricio, Mercedes Camacho, Juan Pablo Muñoz, Joana Rossell and Josep Julve
Nutrients 2023, 15(14), 3083; https://doi.org/10.3390/nu15143083 - 9 Jul 2023
Cited by 8 | Viewed by 3452
Abstract
This study investigated the effect of nicotinamide (NAM) supplementation on the development of brain inflammation and microglial activation in a mouse model of type 1 diabetes mellitus. C57BL/6J male mice, which were made diabetic with five consecutive, low-dose (55 mg/kg i.p.) streptozotocin (STZ) [...] Read more.
This study investigated the effect of nicotinamide (NAM) supplementation on the development of brain inflammation and microglial activation in a mouse model of type 1 diabetes mellitus. C57BL/6J male mice, which were made diabetic with five consecutive, low-dose (55 mg/kg i.p.) streptozotocin (STZ) injections. Diabetic mice were randomly distributed in different experimental groups and challenged to different doses of NAM (untreated, NAM low-dose, LD, 0.1%; NAM high-dose, HD, 0.25%) for 25 days. A control, non-diabetic group of mice was used as a reference. The NAD+ content was increased in the brains of NAM-treated mice compared with untreated diabetic mice (NAM LD: 3-fold; NAM HD: 3-fold, p-value < 0.05). Immunohistochemical staining revealed that markers of inflammation (TNFα: NAM LD: −35%; NAM HD: −46%; p-value < 0.05) and microglial activation (IBA-1: NAM LD: −29%; NAM HD: −50%; p-value < 0.05; BDKRB1: NAM LD: −36%; NAM HD: −37%; p-value < 0.05) in brains from NAM-treated diabetic mice were significantly decreased compared with non-treated T1D mice. This finding was accompanied by a concomitant alleviation of nuclear NFκB (p65) signaling in treated diabetic mice (NFκB (p65): NAM LD: −38%; NAM HD: −53%, p-value < 0.05). Notably, the acetylated form of the nuclear NFκB (p65) was significantly decreased in the brains of NAM-treated, diabetic mice (NAM LD: −48%; NAM HD: −63%, p-value < 0.05) and inversely correlated with NAD+ content (r = −0.50, p-value = 0.03), suggesting increased activity of NAD+-dependent deacetylases in the brains of treated mice. Thus, dietary NAM supplementation in diabetic T1D mice prevented brain inflammation via NAD+-dependent deacetylation mechanisms, suggesting an increased action of sirtuin signaling. Full article
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17 pages, 2290 KiB  
Article
Effect of Grape Pomace Varieties and Soil Characteristics on the Leaching Potential of Total Carbon, Nitrogen and Polyphenols
by Sven Korz, Sullivan Sadzik, Camilla More, Christian Buchmann, Elke Richling and Katherine Munoz
Soil Syst. 2023, 7(2), 49; https://doi.org/10.3390/soilsystems7020049 - 15 May 2023
Cited by 9 | Viewed by 3137
Abstract
Grape pomace (GP) has an added value because of its contribution to carbon (C) and nitrogen (N) in soils when applied as an organic fertilizer. Macronutrients from GP are translocated into the soil after amendment, but little is known about the factors that [...] Read more.
Grape pomace (GP) has an added value because of its contribution to carbon (C) and nitrogen (N) in soils when applied as an organic fertilizer. Macronutrients from GP are translocated into the soil after amendment, but little is known about the factors that may influence the mobility of C, N and bioactive molecules, i.e., polyphenols, in the soil column. We investigated the mobility of the macronutrient content of GP, derived from two red (Dornfelder and Pinot noir) and two white grape varieties (Riesling and Pinot blanc). For that, three different soils (loamy sand RefeSol01A, silt loam RefeSol02A and a vineyard soil) were evaluated in a column model using a GP application rate of 30 t ha−1. The three-step lab-scale approach included the analysis of total C, N and polyphenols expressed as total polyphenolic content (TPC) in: (a) the fresh GP, representing the total amount of C, N and TPC; (b) the mobility with rainwater, representing the aqueous extractable fraction and (c) the mobility in the soil column and leaching potential. Our results showed that total C/N ratios were wider in the white GP varieties compared with the red ones. Higher TPC values were measured in Dornfelder and Pinot noir compared with white varieties. Analysis of the water-extractable fraction showed that the C recovery may reach up to 48% in Pinot blanc, which also corresponds to the highest N contribution. Extractable polyphenols were higher in the red compared with the white varieties by a factor of 2.4. C and N were mobilized with rainwater from the GP through the soil column. However, the application rate used in the experiment was not indicative of an accumulation in the soil. Compared with the control (no GP application), C values were significantly higher in the leachates from GP-treated soils, in contrast to N values. Up to 10% of the TPC of the pomace was leached into the soil. The TPC recovery in the soils strongly depended on the combination of soil type and GP variety. Generally, the sandy and more acidic soil showed an even distribution of phenolics with a high recovery rate (up to 92%) compared with more neutral and silty soil. Most of the polyphenol content could accumulate in the upper soil layer (0–10 cm). These results provide the first insights on the mobility of macronutrients in the soil using a column model and point out the need to relate those experiments to soil and GP properties in order to avoid the accumulation of nutrients in soil or mobility to adjacent ecosystems. Full article
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26 pages, 9563 KiB  
Article
Soil Microbial Responses to Aflatoxin Exposure: Consequences for Biomass, Activity and Catabolic Functionality
by Julius Albert, Camilla More, Sven Korz and Katherine Muñoz
Soil Syst. 2023, 7(1), 23; https://doi.org/10.3390/soilsystems7010023 - 9 Mar 2023
Cited by 7 | Viewed by 2736
Abstract
Aflatoxins (AFs) are fungal secondary metabolites frequently detected in soil that exhibit in vitro toxicity to certain soil microorganisms. However, microbial responses at different levels and in complex systems such as the soil environment have not been systematically studied. Therefore, we investigated multiple [...] Read more.
Aflatoxins (AFs) are fungal secondary metabolites frequently detected in soil that exhibit in vitro toxicity to certain soil microorganisms. However, microbial responses at different levels and in complex systems such as the soil environment have not been systematically studied. Therefore, we investigated multiple microbial responses in two different soils (sandy loam and clay) to aflatoxin B1 (AFB1) at environmentally relevant concentrations (0.5–500 µg kg−1) during a 28-day incubation. General microbial parameters for biomass (microbial biomass carbon and ergosterol), activity (glucose-induced and basal respiration), and catabolic functionality (substrate utilization patterns) were assessed. We observed minor and transient effects in both soils. In sandy loam, we found negative effects on activity and catabolic functionality with increased metabolic quotient, while clay soil exhibited stimulation for the same parameters, suggesting a hormetic effect due to reduced bioavailability through sorption onto clay minerals. Our results indicate that AFB1 does not pose a threat to general microbial indicators under the test conditions in soils without previous AF contamination. Given the toxic potential of AFs to specific microorganisms, further studies should investigate responses at higher taxonomic and functional levels in natural environments of aflatoxigenic fungi, such as tropical soils, and including additional physicochemical stressors. Full article
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19 pages, 8535 KiB  
Article
Identification and Evaluation of (Non-)Intentionally Added Substances in Post-Consumer Recyclates and Their Toxicological Classification
by Christian Rung, Frank Welle, Anita Gruner, Arielle Springer, Zacharias Steinmetz and Katherine Munoz
Recycling 2023, 8(1), 24; https://doi.org/10.3390/recycling8010024 - 9 Feb 2023
Cited by 27 | Viewed by 8828
Abstract
According to the European circular economy strategy, all plastic packaging placed on the market by 2030 has to be recyclable. However, for recycled plastics in direct contact with food, there are still major safety concerns because (non-)intentionally added substances can potentially migrate from [...] Read more.
According to the European circular economy strategy, all plastic packaging placed on the market by 2030 has to be recyclable. However, for recycled plastics in direct contact with food, there are still major safety concerns because (non-)intentionally added substances can potentially migrate from recycled polymers into foodstuffs. Therefore, the European Food Safety Authority (EFSA) has derived very low migration limits (e.g., 0.1 µg/L for recycled polyethylene terephthalate (PET) and 0.06 µg/L for recycled high-density polyethylene (HDPE)) for recycled polymers. Thus, the use of recyclates from post-consumer waste materials in direct food contact is currently only possible for PET. A first step in assessing potential health hazards is, therefore, the identification and toxicological classification of detected substances. Within this study, samples of post-consumer recyclates from different packaging-relevant recycling materials (HDPE, LDPE, PE, PP, PET, and PS) were analyzed. The detected substances were identified and examined with a focus on their abundance, toxicity (Cramer classification), polarity (log P values), chemical diversity, and origin (post-consumer substances vs. virgin base polymer substances). It was demonstrated that polyolefins contain more substances classified as toxic than PET, potentially due to their higher diffusivity. In addition, despite its low diffusivity compared to polyolefins, a high number of substances was found in PS. Further, post-consumer substances were found to be significantly more toxicologically concerning than virgin base polymer substances. Additionally, a correlation between high log P values and a high Cramer classification was found. It was concluded that PET is currently the only polymer that complies with EFSA’s requirements for a circular economy. However, better-structured collection systems and cleaning processes, as well as more analytical methods that enable a highly sensitive detection and identification of substances, might offer the possibility of implementing other polymers into recycling processes in the future. Full article
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Article
Molecular and Clinical Data of Antimicrobial Resistance in Microorganisms Producing Bacteremia in a Multicentric Cohort of Patients with Cancer in a Latin American Country
by Sergio Andrés Cruz-Vargas, Laura García-Muñoz, Sonia Isabel Cuervo-Maldonado, Carlos Arturo Álvarez-Moreno, Carlos Humberto Saavedra-Trujillo, José Camilo Álvarez-Rodríguez, Angélica Arango-Gutiérrez, Julio César Gómez-Rincón, Katherine García-Guzman, Aura Lucía Leal, Javier Garzón-Herazo, Samuel Martínez-Vernaza, Fredy Orlando Guevara, Leydy Paola Jiménez-Cetina, Liliana Marcela Mora, Sandra Yamile Saavedra and Jorge Alberto Cortés
Microorganisms 2023, 11(2), 359; https://doi.org/10.3390/microorganisms11020359 - 31 Jan 2023
Cited by 8 | Viewed by 3346
Abstract
Patients with cancer have a higher risk of severe bacterial infections. This study aims to determine the frequency, susceptibility profiles, and resistance genes of bacterial species involved in bacteremia, as well as risk factors associated with mortality in cancer patients in Colombia. In [...] Read more.
Patients with cancer have a higher risk of severe bacterial infections. This study aims to determine the frequency, susceptibility profiles, and resistance genes of bacterial species involved in bacteremia, as well as risk factors associated with mortality in cancer patients in Colombia. In this prospective multicenter cohort study of adult patients with cancer and bacteremia, susceptibility testing was performed and selected resistance genes were identified. A multivariate regression analysis was carried out for the identification of risk factors for mortality. In 195 patients, 206 microorganisms were isolated. Gram-negative bacteria were more frequently found, in 142 cases (68.9%): 67 Escherichia coli (32.5%), 36 Klebsiella pneumoniae (17.4%), and 21 Pseudomonas aeruginosa (10.1%), and 18 other Gram-negative isolates (8.7%). Staphylococcus aureus represented 12.4% (n = 25). Among the isolates, resistance to at least one antibiotic was identified in 63% of them. Genes coding for extended-spectrum beta-lactamases and carbapenemases, blaCTX-M and blaKPC, respectively, were commonly found. Mortality rate was 25.6% and it was lower in those with adequate empirical antibiotic treatment (22.0% vs. 45.2%, OR: 0.26, 95% CI: 0.1–0.63, in the multivariate model). In Colombia, in patients with cancer and bacteremia, bacteria have a high resistance profile to beta-lactams, with a high incidence of extended-spectrum beta-lactamases and carbapenemases. Adequate empirical treatment diminishes mortality, and empirical selection of treatment in this environment of high resistance is of key importance. Full article
(This article belongs to the Section Medical Microbiology)
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