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1.
Development ; 145(9)2018 05 08.
Article in English | MEDLINE | ID: mdl-29636380

ABSTRACT

The last stage of neural tube (NT) formation involves closure of the caudal neural plate (NP), an embryonic structure formed by neuromesodermal progenitors and newly differentiated cells that becomes incorporated into the NT. Here, we show in mouse that, as cell specification progresses, neuromesodermal progenitors and their progeny undergo significant changes in shape prior to their incorporation into the NT. The caudo-rostral progression towards differentiation is coupled to a gradual reliance on a unique combination of complex mechanisms that drive tissue folding, involving pulses of apical actomyosin contraction and planar polarised cell rearrangements, all of which are regulated by the Wnt-PCP pathway. Indeed, when this pathway is disrupted, either chemically or genetically, the polarisation and morphology of cells within the entire caudal NP is disturbed, producing delays in NT closure. The most severe disruptions of this pathway prevent caudal NT closure and result in spina bifida. In addition, a decrease in Vangl2 gene dosage also appears to promote more rapid progression towards a neural fate, but not the specification of more neural cells.


Subject(s)
Cell Differentiation , Neural Plate/embryology , Neural Stem Cells/metabolism , Neural Tube/embryology , Wnt Signaling Pathway , Animals , Mice , Mice, Mutant Strains , Nerve Tissue Proteins/genetics , Nerve Tissue Proteins/metabolism , Neural Plate/pathology , Neural Stem Cells/pathology , Neural Tube/pathology , Spinal Dysraphism/epidemiology , Spinal Dysraphism/genetics , Spinal Dysraphism/pathology
2.
Dev Dyn ; 248(10): 900-917, 2019 10.
Article in English | MEDLINE | ID: mdl-31361376

ABSTRACT

BACKGROUND: Abnormalities in maternal folate and carbohydrate metabolism have both been shown to induce neural tube defects (NTDs) in humans and animal models. Nevertheless, how these two factors might interact in the development of NTDs remains unclear. RESULTS: In specific mouse models and embryo culture systems, we assessed the effects of combining maternal diabetes with mutations in genes involved in folate transport and metabolism (methylenetetrahydrofolate reductase [Mthfr] and folic acid receptor 1 [Folr1]). When maternal hyperglycemia is combined with alterations in folic acid metabolism, there appears to be an increase in the incidence of congenital malformations in the offspring, with NTDs representing the majority of the malformations detected. CONCLUSIONS: The teratogenic effects of diabetes during pregnancy are exacerbated when combined with altered embryonic folate metabolism.


Subject(s)
Diabetes Mellitus/genetics , Folic Acid/metabolism , Mutation , Neural Tube Defects/etiology , Animals , Disease Models, Animal , Embryo Culture Techniques , Female , Folate Receptor 1/genetics , Folic Acid/genetics , Humans , Methylenetetrahydrofolate Reductase (NADPH2)/genetics , Mice , Pregnancy , Teratogenesis
3.
Bioessays ; 38 Suppl 1: S96-S106, 2016 07.
Article in English | MEDLINE | ID: mdl-27417127

ABSTRACT

Polo-like kinase 1 (PLK1) is a serine/threonine kinase that plays multiple and essential roles during the cell division cycle. Its inhibition in cultured cells leads to severe mitotic aberrancies and cell death. Whereas previous reports suggested that Plk1 depletion in mice leads to a non-mitotic arrest in early embryos, we show here that the bi-allelic Plk1 depletion in mice certainly results in embryonic lethality due to extensive mitotic aberrations at the morula stage, including multi- and mono-polar spindles, impaired chromosome segregation and cytokinesis failure. In addition, the conditional depletion of Plk1 during mid-gestation leads also to severe mitotic aberrancies. Our data also confirms that Plk1 is completely dispensable for mitotic entry in vivo. On the other hand, Plk1 haploinsufficient mice are viable, and Plk1-heterozygous fibroblasts do not harbor any cell cycle alterations. Plk1 is overexpressed in many human tumors, suggesting a therapeutic benefit of inhibiting Plk1, and specific small-molecule inhibitors for this kinase are now being evaluated in clinical trials. Therefore, the different Plk1 mouse models here presented are a valuable tool to reexamine the relevance of the mitotic kinase Plk1 during mammalian development and animal physiology.


Subject(s)
Cell Cycle Proteins/physiology , Chromosome Segregation , Cytokinesis , Mitosis , Protein Serine-Threonine Kinases/physiology , Proto-Oncogene Proteins/physiology , Spindle Apparatus/metabolism , Animals , Female , Male , Mice , Spindle Apparatus/physiology , Polo-Like Kinase 1
4.
J Sci Food Agric ; 98(9): 3246-3254, 2018 Jul.
Article in English | MEDLINE | ID: mdl-29230830

ABSTRACT

BACKGROUND: Addition of persimmon fruit, which is highly rich in carotenoids, to dairy products represents an alternative to obtain functional foods. However, carotenoid bioaccessibility is strongly influenced by fat content and food composition. That is why in vitro bioaccessibility of individual carotenoids was evaluated in persimmon-based dairy products formulated with whole (3.6% fat) or skimmed milk (0.25% fat) and different freeze-dried persimmon tissues. RESULTS: Unambiguous identification of seven xanthophylls (neoxanthin, violaxanthin, antheraxanthin, lutein, zeaxanthin, lutein epoxide and ß-cryptoxanthin) and three hydrocarbon carotenes (α-carotene, ß-carotene and lycopene) was achieved using high-performance liquid chromatography with a reverse-phase C-30 column. Total carotenoid content declined up 71% through the digestion process. In vitro bioaccessibility of carotenoids was significantly higher in dairy products formulated with whole milk than those with skimmed milk, representing a difference of more than 21% (in the formulation using persimmon whole fruit as ingredient). Furthermore, addition of whole milk to any type of persimmon tissue significantly improved the bioaccessibility of total provitamin A carotenoids, reaching the highest values (38%) with whole fruit and whole milk. CONCLUSION: The higher fat content in whole milk exerted a significant influence on carotenoid bioaccessibility, especially when using freeze-dried persimmon whole fruit. © 2017 Society of Chemical Industry.


Subject(s)
Carotenoids/pharmacokinetics , Dairy Products/analysis , Diospyros , Fruit/chemistry , Antioxidants/analysis , Biological Availability , Carotenoids/analysis , Dietary Fats/administration & dosage , Dietary Fats/analysis , Digestion , Pancreatin/metabolism , Pepsin A/metabolism , Xanthophylls/analysis , Xanthophylls/pharmacokinetics
5.
Molecules ; 22(6)2017 Jun 10.
Article in English | MEDLINE | ID: mdl-28604594

ABSTRACT

An efficient synthesis of a series of 4'-oxyalkyl-isocordoin analogues (2-8) is reported for the first time. Their structures were confirmed by ¹H-NMR, 13C-NMR, and HRMS. Their anti-oomycete activity was evaluated by mycelium and spores inhibition assay against two selected pathogenic oomycetes strains: Saprolegnia parasitica and Saprolegnia australis. The entire series of isocordoin derivatives (except compound 7) showed high inhibitory activity against these oomycete strains. Among them, compound 2 exhibited strong activity, with minimum inhibitory concentration (MIC) and minimum oomyceticidal concentration (MOC) values of 50 µg/mL and 75 µg/mL, respectively. The results showed that 4'-oxyalkylated analogues of isocordoin could be potential anti-oomycete agents.


Subject(s)
Catechols/chemistry , Mycelium/drug effects , Saprolegnia/drug effects , Spores, Fungal/drug effects , Antifungal Agents/chemical synthesis , Antifungal Agents/classification , Antifungal Agents/pharmacology , Catechols/chemical synthesis , Catechols/pharmacology , Inorganic Chemicals/chemical synthesis , Inorganic Chemicals/chemistry , Inorganic Chemicals/pharmacology , Microbial Sensitivity Tests , Mycelium/pathogenicity , Saprolegnia/pathogenicity , Spores, Fungal/pathogenicity
6.
Development ; 138(13): 2661-72, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21613325

ABSTRACT

Mitosis is controlled by multiple kinases that drive cell cycle progression and prevent chromosome mis-segregation. Aurora kinase B interacts with survivin, borealin and incenp to form the chromosomal passenger complex (CPC), which is involved in the regulation of microtubule-kinetochore attachments and cytokinesis. Whereas genetic ablation of survivin, borealin or incenp results in early lethality at the morula stage, we show here that aurora B is dispensable for CPC function during early cell divisions and aurora B-null embryos are normally implanted. This is due to a crucial function of aurora C during these early embryonic cycles. Expression of aurora C decreases during late blastocyst stages resulting in post-implantation defects in aurora B-null embryos. These defects correlate with abundant prometaphase figures and apoptotic cell death of the aurora B-deficient inner cell mass. Conditional deletion of aurora B in somatic cells that do not express aurora C results in chromosomal misalignment and lack of chromosome segregation. Re-expression of wild-type, but not kinase-dead, aurora C rescues this defect, suggesting functional overlap between these two kinases. Finally, aurora B-null cells partially arrest in the presence of nocodazole, suggesting that this kinase is not essential for the spindle assembly checkpoint.


Subject(s)
Protein Serine-Threonine Kinases/metabolism , Animals , Aurora Kinase B , Aurora Kinase C , Aurora Kinases , Blastocyst/metabolism , Cell Division/genetics , Cell Division/physiology , Cells, Cultured , Chromosome Segregation/genetics , Chromosome Segregation/physiology , Female , Fluorescent Antibody Technique , Gene Expression Regulation, Developmental/genetics , Gene Expression Regulation, Developmental/physiology , Mice , Mice, Transgenic , Mitosis/genetics , Mitosis/physiology , Pregnancy , Protein Serine-Threonine Kinases/genetics , Spindle Apparatus/genetics , Spindle Apparatus/metabolism , Zygote/metabolism
7.
Prev Vet Med ; 224: 106139, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38341943

ABSTRACT

Antimicrobial Resistance (AMR) represents one of the main current threats to global public health; where production animals, companion animals, humans, and the environment play a significant role in its dissemination. However, little attention has been given to companion animals as reservoirs and disseminators of relevant antimicrobial resistant bacteria, especially in South American countries such as Chile. For this reason, this research aimed to estimate the prevalence of AMR to different critical antibiotics at a screening level in commensal bacteria such as E. coli and Enterococcus spp., isolated from healthy pet dogs in the Metropolitan Region of Chile, studying their geographical distribution and evaluating associations of phenotypic resistance to different antibiotics. Thus, in E. coli we detected AMR to all critical drugs assessed, including 34.1% to amoxicillin, 20.1% to colistin, 15.7% to enrofloxacin, and 9.2% to cefotaxime. On the other hand, AMR prevalence in E. faecalis was 8.1% for ampicillin and 3.4% for vancomycin; while for E. faecium the AMR prevalence was 19.1% for ampicillin and 10.2% for vancomycin. Additionally, significant differences in prevalence of the different possible AMR were detected according to their geographical distribution, suggesting the existence of various risk factors and stressing the need to establish mitigation measures specific to the differences identified.


Subject(s)
Anti-Bacterial Agents , Enterococcus faecium , Dogs , Animals , Humans , Anti-Bacterial Agents/pharmacology , Enterococcus faecalis , Vancomycin , Escherichia coli , Chile/epidemiology , Drug Resistance, Bacterial , Ampicillin , Microbial Sensitivity Tests/veterinary
8.
Dev Dyn ; 241(11): 1808-15, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22911573

ABSTRACT

BACKGROUND: The ventral ectodermal ridge (VER) is an important signalling centre in the mouse tail-bud following completion of gastrulation. BMP regulation is essential for VER function, but how these signals are transmitted between adjacent tissues is unclear. RESULTS: We investigated the idea that extracellular matrix components might be involved, using immunohistochemistry and in situ hybridisation to detect all known α, ß, and γ laminin chains and their mRNAs in the early tail bud. We identified an apparently novel laminin variant, comprising α5, ß3 and γ2 chains, as a major component of the VER basement membrane at E9.5. Strikingly, only the mRNAs for these chains were co-expressed in VER cells, suggesting that lamin532 may be the sole basement membrane laminin at this stage. Since α6 integrin was also expressed in VER cells, this raises the possibility of cell-matrix interactions regulating BMP signalling at this site of caudal morphogenesis. CONCLUSIONS: Laminin532 could interact with α6-containing integrin to direct differentiation of the specialised VER cells from surface ectoderm.


Subject(s)
Bone Morphogenetic Proteins/metabolism , Ectoderm/metabolism , Integrins/metabolism , Laminin/metabolism , Animals , Bone Morphogenetic Proteins/genetics , Ectoderm/embryology , Extracellular Matrix/genetics , Extracellular Matrix/metabolism , Immunohistochemistry , In Situ Hybridization , Integrins/genetics , Laminin/genetics , Mice , Signal Transduction/genetics , Signal Transduction/physiology
9.
Heliyon ; 9(6): e16707, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37287605

ABSTRACT

Zero-export photovoltaic systems are an option to transition to Smart Grids. They decarbonize the sector without affecting third parties. This paper proposes the analysis of a zero-export PVS with a green hydrogen generation and storage system. This configuration is feasible to apply by any self-generation entity; it allows the user to increase their resilience and independence from the electrical network. The technical issue is simplified because the grid supplies no power. The main challenge is finding an economic balance between the savings in electricity billing, proportional to the local electricity rate, and the complete system's investment, operation, and maintenance expenses. This manuscript presents the effects of the power sizing on the efficacy of economic savings in billing (ηSaving) and the effects of the cost reduction on the levelized cost of energy (LCOE) and a discounted payback period (DPP) based on net present value. In addition, this study established an analytical relationship between LCOE and DPP. The designed methodology proposes to size and selects systems to use and store green hydrogen from the zero-export photovoltaic system. The input data in the case study are obtained experimentally from the Autonomous University of the State of Quintana Roo, located on Mexico's southern border. The maximum power of the load is LPmax = 500 kW, and the average power is LPmean = 250 kW; the tariff of the electricity network operator has hourly conditions for a medium voltage demand. A suggested semi-empirical equation allows for determining the efficiency of the fuel cell and electrolyzer as a function of the local operating conditions and the nominal power of the components. The analytical strategy, the energy balance equations, and the identity functions that delimit the operating conditions are detailed to be generalized to other case studies. The results are obtained by a computer code programmed in C++ language. According to our boundary conditions, results show no significant savings generated by the installation of the hydrogen system when the zero-export photovoltaic system Power ≤ LPmax and DPP ≤ 20 years is possible only with LCOE ≤ 0.1 $/kWh. Specifically for the Mexico University case study, zero-export photovoltaic system cost must be less than 310 $/kW, fuel cell cost less than 395 $/kW, and electrolyzer cost less than 460 $/kW.

10.
Front Vet Sci ; 10: 1233127, 2023.
Article in English | MEDLINE | ID: mdl-37655259

ABSTRACT

Introduction: Antimicrobial resistance (AMR) is a major threat to animal and public health worldwide; consequently, several AMR surveillances programs have been implemented internationally in both human and veterinary medicine, including indicator bacteria such as Escherichia coli. However, companion animals are not typically included in these surveillance programs. Nevertheless, there have been reports of increasing levels of antimicrobial resistance in E. coli strains isolated from dogs worldwide. In Chile, there is limited information available on AMR in E. coli isolated from companion animals, which prevents the establishment of objective prevention and control measures. Methods: For this reason, the aim of this study was to characterize the phenotypic and genotypic AMR of E. coli strains isolated from healthy household dogs in Chile. For this purpose, a multi-stage sampling was carried out in the Metropolitan Region of Chile, obtaining samples from 600 healthy dogs. These samples were processed using traditional bacteriology and molecular techniques to isolate E. coli strains. We assessed the minimal inhibitory concentration of 17 antimicrobials and conducted a search of six antimicrobial resistance genes, as well as class 1 and 2 integrons, in the isolated strains. Results: Two-hundred and twenty-four strains of E. coli were recovered, and 96.9% (n = 217) showed resistance to at least one drug and only 3.1% (n = 7) were susceptible to all analyzed antimicrobials. Most strains were resistant to cefalexin (91.5%, n = 205, 1st-generation cephalosporin), followed by ampicillin (68.3%, n = 153) and cefpodoxime (31.3%, n = 70, 3rd-generation cephalosporin). Moreover, 24.1% (n = 54) tested positive for extended-spectrum-ß-lactamases and 34.4% (n = 77) were multidrug resistant. As for the AMR genes, the most detected was qnrB (28.1%, n = 63), followed by blaCTX-M (22.3%, n = 50), and blaTEM-1 (19.6%, n = 44). Additionally, 16.1% (n = 36) harbored class 1 integrons. Our study shows that E. coli strains isolated from healthy household dogs exhibit resistance to several relevant drugs and also antimicrobial resistance genes considered critical for human health. These results can be used as a starting point for the prevention and control of antimicrobial resistance from companion animals. This background should be considered when formulating future resistance surveillance programs or control plans in which companion animals must be included.

11.
STAR Protoc ; 2(4): 100980, 2021 12 17.
Article in English | MEDLINE | ID: mdl-34927090

ABSTRACT

Cardiac function and morphology by mouse fetal echocardiography can be assessed by scanning the uterus extracted from the abdominal cavity (trans-uterine ultrasound) or the womb (trans-abdominal ultrasound). Advantages of trans-abdominal ultrasound include (1) non-invasive longitudinal analysis at different stages, reducing animal use; and (2) maintenance of natural environment, diminishing perturbations on functional parameters, which are more frequent in trans-uterine conditions. Here we describe both approaches, explaining how to identify congenital cardiac defects and defining the correlation between echocardiography findings and histological analysis. For complete details on the use and execution of this protocol, please refer to (Menendez-Montes et al., 2016) and (Menendez-Montes et al., 2021).


Subject(s)
Echocardiography/methods , Embryo, Mammalian/diagnostic imaging , Fetal Heart/diagnostic imaging , Heart Defects, Congenital/diagnostic imaging , Image Interpretation, Computer-Assisted/methods , Animals , Female , Male , Mice , Pregnancy , Ultrasonography, Prenatal/methods
12.
Membranes (Basel) ; 11(5)2021 May 14.
Article in English | MEDLINE | ID: mdl-34068836

ABSTRACT

The study of the microstructure of random heterogeneous materials, related to an electrochemical device, is relevant because their effective macroscopic properties, e.g., electrical or proton conductivity, are a function of their effective transport coefficients (ETC). The magnitude of ETC depends on the distribution and properties of the material phase. In this work, an algorithm is developed to generate stochastic two-phase (binary) image configurations with multiple geometries and polydispersed particle sizes. The recognizable geometry in the images is represented by the white phase dispersed and characterized by statistical descriptors (two-point and line-path correlation functions). Percolation is obtained for the geometries by identifying an infinite cluster to guarantee the connection between the edges of the microstructures. Finally, the finite volume method is used to determine the ETC. Agglomerate phase results show that the geometry with the highest local current distribution is the triangular geometry. In the matrix phase, the most significant results are obtained by circular geometry, while the lowest is obtained by the 3-sided polygon. The proposed methodology allows to establish criteria based on percolation and surface fraction to assure effective electrical conduction according to their geometric distribution; results provide an insight for the microstructure development with high projection to be used to improve the electrode of a Membrane Electrode Assembly (MEA).

13.
Animals (Basel) ; 11(7)2021 Jul 02.
Article in English | MEDLINE | ID: mdl-34359107

ABSTRACT

Brucella abortus, B. canis, and pathogenic Leptospira are zoonotic pathogens that infect humans, as well as domestic and wild animals. In wild canids, they may affect their fertility and reproduction, threatening their conservation. Wild canids play a crucial role in the environment as meso- and top-predators and environmental sentinels for zoonotic pathogens. In Chile, three species of wild canids are present, and due to changes in land use and environmental dynamics, it is of utmost relevance to determine the role of these species in the epidemiology of brucellosis and leptospirosis. This study aimed to detect the exposure to B. abortus, B. canis, and pathogenic Leptospira by serologic, bacteriologic, and molecular techniques in native foxes from rehabilitation and exhibition centers in Central Chile. Forty-six blood samples were obtained from Lycalopex culpaeus and L. griseus, detecting 10.9% of seropositivity to B. canis and 7.7% to L. Javanica. No seropositivity was seen for B. abortus. Exposure was not registered by culture and qPCR in any of the sampled animals. Our findings are the first register of exposure to any Brucella species in wild canids in Chile and highlight the need to establish surveillance programs of these emerging pathogens.

14.
Animals (Basel) ; 11(7)2021 Jun 22.
Article in English | MEDLINE | ID: mdl-34206206

ABSTRACT

Shiga toxin-producing Escherichia coli (STEC) are zoonotic pathogens responsible for causing food-borne diseases in humans. While South America has the highest incidence of human STEC infections, information about the genomic characteristics of the circulating strains is scarce. The aim of this study was to analyze genomic data of STEC strains isolated in South America from cattle, beef, and humans; predicting the antibiotic resistome, serotypes, sequence types (STs), clonal complexes (CCs) and phylogenomic backgrounds. A total of 130 whole genome sequences of STEC strains were analyzed, where 39.2% were isolated from cattle, 36.9% from beef, and 23.8% from humans. The ST11 was the most predicted (20.8%) and included O-:H7 (10.8%) and O157:H7 (10%) serotypes. The successful expansion of non-O157 clones such as ST16/CC29-O111:H8 and ST21/CC29-O26:H11 is highlighted, suggesting multilateral trade and travel. Virulome analyses showed that the predominant stx subtype was stx2a (54.6%); most strains carried ehaA (96.2%), iha (91.5%) and lpfA (77.7%) genes. We present genomic data that can be used to support the surveillance of STEC strains circulating at the livestock-food-human interface in South America, in order to control the spread of critical clones "from farm to table".

15.
Zoonoses Public Health ; 68(3): 226-238, 2021 05.
Article in English | MEDLINE | ID: mdl-33619864

ABSTRACT

Shiga toxin-producing Escherichia coli (STEC) is a zoonotic pathogen that causes severe illness in humans, often associated with foodborne outbreaks. Antimicrobial resistance among foodborne E. coli has increased over the last decades becoming a public health issue. In this study, the presence and features of STEC were investigated in samples of meat, seafood, vegetables and ready-to-eat street-vended food collected in Chile, using a genomic and microbiological approach. Phenotypic and genotypic antimicrobial resistance profiles were determined, and serotype, phylogroup, sequence type (ST) and phylogenomics were predicted using bioinformatic tools. Three thousand three hundred samples collected in 2019 were screened, of which 18 were positive for STEC strains (0.5%), with stx2a (61.1%) being the predominant stx subtype. The presence of the virulence genes lpfA (100%), iha and ehaA (94.4%), and ehxA, hlyA and saa (83.3%) was confirmed among the STEC strains; the Locus of adhesion and autoaggregation (LAA) was predicted in 14 (77.8%) strains. Strains displayed resistance to colistin (100%), and intermediate resistance to enrofloxacin (11.1%) and chloramphenicol (5.6%). In this regard, mutations in the two-component regulatory system genes pmrA (S29G), pmrB (D283G) and phoP (I44L), and the presence of the qnrB19 gene were confirmed. STEC strains belonged to ST11231 (38.9%), ST297 and ST58 (16.7% each), and ST1635, ST11232, ST446, ST442 and ST54 (5.6% each), and the most frequently detected serotypes were O113:H21 (44.4%), O130:H11 and O116:H21 (16.7% each), and O174:H21 (11.1%). Strains belonging to the international ST58 showed genomic relatedness with worldwide strains from human and non-human sources. Our study reports for the first time the genomic profile of STEC strains isolated from food in Chile, highlighting the presence of international clones and sequence types commonly associated with human infections in different geographical regions, as well as the convergence of virulence and resistance in STEC lineages circulating in this country.


Subject(s)
Anti-Bacterial Agents/pharmacology , Food Microbiology , Shiga-Toxigenic Escherichia coli/genetics , Chile , Drug Resistance, Bacterial , Genome, Bacterial , Genomics , Humans , Phylogeny , Whole Genome Sequencing
16.
iScience ; 24(2): 102124, 2021 Feb 19.
Article in English | MEDLINE | ID: mdl-33665549

ABSTRACT

HIF1-alpha expression defines metabolic compartments in the developing heart, promoting glycolytic program in the compact myocardium and mitochondrial enrichment in the trabeculae. Nonetheless, its role in cardiogenesis is debated. To assess the importance of HIF1-alpha during heart development and the influence of glycolysis in ventricular chamber formation, herein we generated conditional knockout models of Hif1a in Nkx2.5 cardiac progenitors and cardiomyocytes. Deletion of Hif1a impairs embryonic glycolysis without influencing cardiomyocyte proliferation and results in increased mitochondrial number and transient activation of amino acid catabolism together with HIF2α and ATF4 upregulation by E12.5. Hif1a mutants display normal fatty acid oxidation program and do not show cardiac dysfunction in the adulthood. Our results demonstrate that cardiac HIF1 signaling and glycolysis are dispensable for mouse heart development and reveal the metabolic flexibility of the embryonic myocardium to consume amino acids, raising the potential use of alternative metabolic substrates as therapeutic interventions during ischemic events.

17.
Animals (Basel) ; 10(11)2020 Nov 09.
Article in English | MEDLINE | ID: mdl-33182313

ABSTRACT

Canine brucellosis caused by Brucella canis is a zoonotic disease that causes reproductive alterations in dogs, such as infertility, abortion, and epididymitis. This pathogen is especially prevalent in South America, and due to the lack of official control programs and the growing trend of adopting dogs it constitutes a public health risk that must be addressed. The aim of this study was to determine the prevalence of B. canis infection in kennel, shelter, and household dogs and to characterize the genomic properties of circulating strains, including ure and virB operons and omp25/31 genes. Samples from 771 dogs were obtained, and the infection was detected by blood culture and/or serology in 7.0% of the animals. The complete ure and virB operons and the omp25/31 genes were detected. Interestingly, we found different single-nucleotide polymorphisms (SNPs) in some of the analyzed genes, which could mean a change in the fitness or virulence of these strains. This study provides further evidence about dogs as a source of B. canis strains that can infect people. This also highlights the need to implement official control programs, including the mandatory testing of dogs, especially stray dogs, before adoption.

18.
Front Vet Sci ; 7: 367, 2020.
Article in English | MEDLINE | ID: mdl-32754621

ABSTRACT

Non-O157 Shiga toxin-producing Escherichia coli (STEC) is a zoonotic pathogen that causes bloody diarrhea and hemolytic-uremic syndrome in humans, and a major cause of foodborne disease. Despite antibiotic treatment of STEC infections in humans is not recommended, the presence of antimicrobial-resistant bacteria in animals and food constitutes a risk to public health, as the pool of genes from which pathogenic bacteria can acquire antibiotic resistance has increased. Additionally, in Chile there is no information on the antimicrobial resistance of this pathogen in livestock. Thus, the aim of this study was to characterize the phenotypic and genotypic antimicrobial resistance of STEC strains isolated from cattle and swine in the Metropolitan region, Chile, to contribute relevant data to antimicrobial resistance surveillance programs at national and international level. We assessed the minimal inhibitory concentration of 18 antimicrobials, and the distribution of 12 antimicrobial resistance genes and class 1 and 2 integrons in 54 STEC strains. All strains were phenotypically resistant to at least one antimicrobial drug, with a 100% of resistance to cefalexin, followed by colistin (81.5%), chloramphenicol (14.8%), ampicillin and enrofloxacin (5.6% each), doxycycline (3.7%), and cefovecin (1.9%). Most detected antibiotic resistance genes were dfrA1 and tetA (100%), followed by tetB (94.4%), bla TEM-1 (90.7%), aac(6)-Ib (88.9%), bla AmpC (81.5%), cat1 (61.1%), and aac(3)-IIa (11.1%). Integrons were detected only in strains of swine origin. Therefore, this study provides further evidence that non-O157 STEC strains present in livestock in the Metropolitan region of Chile exhibit phenotypic and genotypic resistance against antimicrobials that are critical for human and veterinary medicine, representing a major threat for public health. Additionally, these strains could have a competitive advantage in the presence of antimicrobial selective pressure, leading to an increase in food contamination. This study highlights the need for coordinated local and global actions regarding the use of antimicrobials in animal food production.

19.
Front Vet Sci ; 7: 595149, 2020.
Article in English | MEDLINE | ID: mdl-33521079

ABSTRACT

Shiga toxin-producing Escherichia coli (STEC) is a zoonotic pathogen and important cause of foodborne disease worldwide. Many animal species in backyard production systems (BPS) harbor STEC, systems characterized by low biosecurity and technification. No information is reported on STEC circulation, antimicrobial resistance (AMR) and potential drivers of antimicrobial usage in Chilean BPS, increasing the risk of maintenance and transmission of zoonotic pathogens and AMR generation. Thus, the aim of this study was to characterize phenotypic and genotypic AMR and to study the epidemiology of STEC isolated in BPS from Metropolitana region, Chile. A total of 85 BPS were sampled. Minimal inhibitory concentration and whole genome sequencing was assessed in 10 STEC strain isolated from BPS. All strains were cephalexin-resistant (100%, n = 10), and five strains were resistant to chloramphenicol (50%). The most frequent serotype was O113:H21 (40%), followed by O76:H19 (40%), O91:H14 (10%), and O130:H11 (10%). The stx1 type was detected in all isolated strains, while stx2 was only detected in two strains. The Stx subtype most frequently detected was stx1c (80%), followed by stx1a (20%), stx2b (10%), and stx2d (10%). All strains harbored chromosomal bla AmpC. Principal component analysis shows that BPS size, number of cattle, pet and horse, and elevation act as driver of antimicrobial usage. Logistic multivariable regression shows that recognition of diseases in animals (p = 0.038; OR = 9.382; 95% CI: 1.138-77.345), neighboring poultry and/or swine BPS (p = 0.006; OR = 10.564; 95% CI: 1.996-55.894), visit of Veterinary Officials (p = 0.010; OR = 76.178; 95% CI: 2.860-2029.315) and close contact between animal species in the BPS (p = 0.021; OR = 9.030; 95% CI: 1.385-58.888) increase significantly the risk of antimicrobial use in BPS. This is the first evidence of STEC strains circulating in BPS in Chile, exhibiting phenotypic AMR, representing a threat for animal and public health. Additionally, we identified factors acting as drivers for antimicrobial usage in BPS, highlighting the importance of integration of these populations into surveillance and education programs to tackle the potential development of antimicrobial resistance and therefore the risk for ecosystemic health.

20.
Sci Rep ; 10(1): 7615, 2020 05 06.
Article in English | MEDLINE | ID: mdl-32376856

ABSTRACT

The use of first and second generation antiepileptic drugs during pregnancy doubles the risk of major congenital malformations and other teratogenic defects. Lacosamide (LCM) is a third-generation antiepileptic drug that interacts with collapsing response mediator protein 2, a protein that has been associated with neurodevelopmental diseases like schizophrenia. The aim of this study was to test the potential teratogenic effects of LCM on developing embryos and its effects on behavioural/histological alterations in adult mice. We administered LCM to pregnant mice, assessing its presence, and that of related compounds, in the mothers' serum and in embryonic tissues using liquid chromatography coupled to quadrupole/time of flight mass spectrometry detection. Embryo morphology was evaluated, and immunohistochemistry was performed on adult offspring. Behavioural studies were carried out during the first two postnatal weeks and on adult mice. We found a high incidence of embryonic lethality and malformations in mice exposed to LCM during embryonic development. Neonatal mice born to dams treated with LCM during gestation displayed clear psychomotor delay and behavioural and morphological alterations in the prefrontal cortex, hippocampus and amygdala that were associated with behaviours associated with schizophrenia spectrum disorders in adulthood. We conclude that LCM and its metabolites may have teratogenic effects on the developing embryos, reflected in embryonic lethality and malformations, as well as behavioural and histological alterations in adult mice that resemble those presented by patients with schizophrenia.


Subject(s)
Fetus/abnormalities , Fetus/drug effects , Lacosamide/adverse effects , Prenatal Exposure Delayed Effects/physiopathology , Schizophrenia/physiopathology , Affect/drug effects , Animals , Dose-Response Relationship, Drug , Female , Incidence , Locomotion/drug effects , Memory/drug effects , Mice , Pregnancy
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