Publications by authors named "Juan Alfaro"

We report the isolation, identification, and assemblies of three antibiotic-producing soil bacteria (Staphylococcus pasteuri, Peribacillus butanolivorans, and Micrococcus yunnanensis) that inhibit the growth of commensals in coculture. With pathogenic strains becoming increasingly resistant to antibiotics, bioprospecting for novel antimicrobials using commensal relatives may facilitate discovery of clinically useful drugs.

View Article and Find Full Text PDF

In Chile, tomato is one of the most widely cultivated vegetables, with around 5,000 ha for fresh market and 8,000 ha for processing industry. During recent years, symptoms of bacterial speck caused by pv. , have been observed more frequently in tomato plants in different regions of Chile.

View Article and Find Full Text PDF

Hydrogen sulfide (HS) plays several physiological roles in plants. Despite the evidence, the role of HS on cell wall disassembly and its implications on fleshy fruit firmness remains unknown. In this work, the effect of HS treatment on the shelf-life, cell wall polymers and cell wall modifying-related gene expression of Chilean strawberry () fruit was tested during postharvest storage.

View Article and Find Full Text PDF

The goal of the is to learn that predict the preferred ranking of class labels for a given unlabeled instance. Different well-known machine learning algorithms have been adapted to deal with the LR problem. In particular, fine-tuned instance-based algorithms (e.

View Article and Find Full Text PDF

The real burden of community-acquired pneumonia (CAP) in non-hospitalized patients is largely unknown. This is a 3-year prospective, observational study of ambulatory CAP in adults, conducted in 24 Spanish primary care centers between 2016-2019. Sociodemographic and clinical variables of patients with radiographically confirmed CAP were collected.

View Article and Find Full Text PDF

An evaluation of antioxidant and anticancer activity was screened in DC flower extracts using four solvents (-hexane (Hex), dichloromethane (DCM), ethyl acetate (AcOEt), and ethanol (EtOH)). Extracts were compared for total extract flavonoids and phenol contents, antioxidant activity (2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), ferric reducing antioxidant potential (FRAP), total reactive antioxidant properties (TRAP) and oxygen radical absorbance capacity (ORAC)) across a determined value of reduced/oxidized glutathione (GSH/GSSG), and cell viability (the sulforhodamine B (SRB) assay). The most active extracts were analyzed by chromatographic analysis (GC/MS) and tested for apoptotic pathways.

View Article and Find Full Text PDF

Background: Type 1 diabetes (T1D) is a complex disease with a higher incidence in Europeans than other populations. The Colombians Living in Medellin (CLM) is admixed with ancestry contributions from Europeans, Native Americans (NAT) and Africans (AFR).

Aim: Our aim was to analyze the genetic admixture component at candidate T1D loci in Colombian individuals with the disease.

View Article and Find Full Text PDF

Introduction: The HLA region strongly associates with autoimmune diseases, such as type 1 diabetes. An alternative way to test classical HLA alleles is by using tag SNP. A set of tag SNP for several classical HLA alleles has been reported as associated with susceptibility or resistance to this disease in Europeans.

View Article and Find Full Text PDF

Tomato crops can be affected by several infectious diseases produced by bacteria, fungi, and oomycetes. Four phytopathogens are of special concern because of the major economic losses they generate worldwide in tomato production; subsp. and pv.

View Article and Find Full Text PDF

Becker's nevus syndrome is part of the epidermal nevus syndromes and has been described with a phenotype that includes Becker's nevus, ipsilateral breast hypoplasia, and variable skeletal malformations. It is more frequent in males than in females (5 : 1) but is more relevant in females. The diagnosis is clinically based and the skin lesion must be present and no other numbered criteria have been established, but with more criteria being present the possibility of the diagnosis is higher.

View Article and Find Full Text PDF

Background: Protein tyrosine phosphatase, non-receptor type 22 (lymphoid) (PTPN22), cytotoxic T-lymphocyte-associated protein 4 (CTLA4), and interferon induced with helicase C domain 1 (IFIH1) are among the confirmed type 1 diabetes (T1D) susceptibility genes in several populations. The aim of this study was to evaluate the role of PTPN22, CTLA4, and IFIH1 gene variants in the development of T1D in a Colombian population.

Methods: Associations of PTPN22, CTLA4, and IFIH1 variants with T1D were investigated in a sample of 197 nuclear families, including 205 affected children, in the Colombian population.

View Article and Find Full Text PDF

Docosahexaeonic acid (DHA) is the final compound in the omega-3 polyunsaturated fatty acids (PUFA) synthetic pathway and the most abundant PUFA found in the brain. DHA plays an essential role in the development of the brain, and the intakes in pregnancy and early life affect growth and cognitive performance later in childhood. Recently, it has been proposed that dietary intake of DHA could be a non-pharmacological interventional strategy for the treatment of seizures in humans.

View Article and Find Full Text PDF

Glutamate is the major excitatory neurotransmitter of the central nervous system in vertebrates. Excitotoxicity, caused by over-stimulation of the glutamate receptors, is a major cause of neuron death in several brain diseases, including epilepsy. We describe here how behavioural seizures can be triggered in adult zebrafish by the administration of kainate and are very similar to those observed in rodent models.

View Article and Find Full Text PDF

N-Heterocyclic carbene (NHC) ligands have attracted great interest over the last decade for their use in the design of homogenous catalysts. NHC-based metal complexes have interesting potential biomedical applications, such as in antimicrobial and cancer therapy, which are beginning to be explored more fully. We have studied here the oxidant activities of a series of Ru(II) complexes in vitro and zebrafish (Danio rerio) have been used as a model in vivo to investigate and characterize the toxicity of some of these compounds.

View Article and Find Full Text PDF

The frequency and functionality of peripheral blood invariant (iNKT) cells and their subsets, as well as other regulatory T-cell subsets, were evaluated in patients with type 1A diabetes mellitus (DM1), Hashimoto's disease, and Graves' disease. In addition to healthy individuals (HC), patients with type 2 diabetes mellitus (DM2) were included as controls because this disease has a different physiopathology. A similar frequency of total iNKT cells, as well as their subsets, existed among HC and the different study groups.

View Article and Find Full Text PDF

The zebrafish (Danio rerio) is rapidly gaining ground as a disease model. However, until now, the use of this species with human pathogens has been restricted to just three bacteria; no studies involving viruses that infect humans are recorded. In this study, the zebrafish was used as a model of herpes simplex virus type 1 (HSV-1) infection of the nervous system.

View Article and Find Full Text PDF

Disseminated herpes simplex virus type 1 (HSV-1) infection during pregnancy is poorly described even though it is associated with high maternal and fetal morbidity and neonatal mortality in humans. In a previous paper using mice as a model, the authors demonstrated that HSV-1 is transmitted hematogenously from mother to offspring, the virus colonizing the central nervous system and provoking high mortality. In the present study, viral DNA levels in latently infected mothers were investigated during pregnancy and after delivery in mice.

View Article and Find Full Text PDF

Herpes simplex virus type 1 (HSV-1) is a neurotropic virus that causes severe disease and death in newborn humans but, to date, it remains unclear how neonatal infection occurs. We show here that the vertical transmission of HSV-1 in mice is mainly hematogenous and involves the colonization of the neonate central nervous system (CNS). HSV-1 DNA was mainly detected in the blood and CNS of the offspring born to latently infected mothers; no significant differences were seen between the viral DNA concentrations in the blood of these mothers and their female progeny (either neonate or adult).

View Article and Find Full Text PDF

Herpes simplex virus type 1 (HSV-1) causes disease in humans and animals. Infection usually occurs via the neural route and possibly occurs via the hematogenous route. The latter, however, is the main route by which immunosuppressed individuals and neonates are infected.

View Article and Find Full Text PDF

Objective: To estimate the occurrence and school-level clustering of drug involvement among school-attending adolescent youths in each of seven countries in Latin America, drawing upon evidence from the PACARDO research project, a multinational collaborative epidemiological research study.

Methods: During 1999-2000, anonymous self-administered questionnaires on drug involvement and related behaviors were administered to a cross-sectional, nationally representative sample that included a total of 12,797 students in the following seven countries: Costa Rica (n = 1,702), the Dominican Republic (n = 2,023), El Salvador (n = 1,628), Guatemala (n = 2,530), Honduras (n = 1,752), Nicaragua (n = , 419), and Panama (n = 1,743). (The PACARDO name concatenates PA for Panamá, CA for Centroamérica, and RDO for República Dominicana).

View Article and Find Full Text PDF

Background: So far there have been no reports on the expression pattern of DAX-1 (dosage-sensitive sex reversal, adrenal hypoplasia critical region, on chromosome X, gene 1) in human breast cells and its relationship to the estrogen receptors, ER-alpha and ER-beta, and the androgen receptor (AR).

Methods: In this study we evaluated, by immunohistochemistry and Western blot analysis, the presence and distribution of DAX-1 in benign breast disease (BBD), in situ carcinoma (CIS), and ductal and lobular breast carcinomas.

Results: In BBD and breast carcinomas, DAX-1 was present in both the nuclei and the cytoplasm of epithelial cells, although in infiltrative carcinomas the percentage of nuclear immunoreaction was higher than in CIS.

View Article and Find Full Text PDF

The aim of this study was to evaluate the presence and distribution of retinoid X receptors (RXRs) alpha, beta, and gamma in normal, hyperplastic (nodular, basal cell, and atrophic hyperplasia), and carcinomatous human prostates in order to elucidate the relationship among these receptors and the onset and development of prostatic adenocarcinoma. RXRalpha and RXRgamma were immunodetected in all samples of normal, nodular, and basal cell hyperplasia, as well as carcinomatous prostates. In atrophic glands, the expression of both receptors was found in 22.

View Article and Find Full Text PDF

Standard histochemical analysis of cells and tissues generally involves procedures that utilize a relatively small number of probes such as dyes, and generally requires hours or days to process. Our laboratory has developed a novel method for histochemical surveys of cell surface properties that utilizes a large number of probes (derivatized agarose beads) and takes seconds or minutes to accomplish. In this study, 4 human cell lines (CCL-255 (LS123) human colon cancer cells that are non-tumorigenic in nude mice; CRL-1459 (CCD-18CO) human colon endothelial cells that are non-malignant; CCL-220 (COLO 320DM) human colon cancer cells that are tumorigenic in nude mice; and HTB-171 (NCI H446) human lung carcinoma cells) were tested for their ability to bind to agarose beads derivatized with 51 different molecules.

View Article and Find Full Text PDF

p53, p21, and Rb are proteins with an important role in cell-cycle control. The expression and distribution of these gene products and the apoptotic rate were studied in the marbled-newt testis along the annual cycle to know the role of these factors in the control of spermatogenesis and glandular tissue formation. The study was carried out using Western blot analysis and immunohistochemistry.

View Article and Find Full Text PDF