Publications by authors named "Jaime Tapia"

Exopolysaccharides (EPSs), a constitutive part of bacterial biofilm, act as a protecting sheath to the extremophilic bacteria and are of high industrial value. In this study, we elucidate a new EPS produced by thermotolerant (growth from 34-44 °C) strain Pseudomonas alcaligenes Med1 from Medano hot spring (39.1 °C surface temperature, pH 7.

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A type of high molecular weight bioactive polymers called exopolysaccharides (EPS) are produced by thermophiles, the extremophilic microbes that thrive in acidic environmental conditions of hot springs with excessively warm temperatures. Over time, EPS became important as natural biotechnological additives because of their noncytotoxic, emulsifying, antioxidant, or immunostimulant activities. In this article, we unravelled a new EPS produced by Staphylococcus sp.

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Objective: To describe the presence of obstructive sleep apnea syndrome (OSAS) in children with craniofacial anomalies (CFA), associate biodemographic characteristics and polygraph variables, and analyze the therapeutic management decided after the sleep study and the evaluation by a multidisciplinary team.

Patients And Method: Retrospective study. Polygraphs were performed on patients aged between 1 month and 19 years with CFA.

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Extremophilic microorganisms often produce novel bioactive compounds to survive under harsh environmental conditions. Exopolysaccharides (EPSs), a constitutive part of bacterial biofilm, are functional biopolymers that act as a protecting sheath to the extremophilic bacteria and are of high industrial value. In this study, we elucidate a new EPS produced by thermophilic CamB6 from a slightly acidic (pH 5.

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(Kunt) is one of the two vascular plant species present in Antarctica and develops under severe environmental conditions, being found in both pristine and human-threatened environments. We determined the Cd, Cr, Cu, Mn, Ni, Pb, and Zn levels in roots, leaves, and soils of origin using flame atomic absorption spectroscopy. In January 2017, we collected samples from four geographical zones on the longitudinal gradient along which is distributed, starting from Punta Arenas (PAR) at the extreme south of mainland Chile and moving southwards to the Antarctic territory from King George Island (KGI) to Hannah Point Peninsula (PHA) and finally Lagotellerie Island (LAT).

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The brain's immune system is selective and hermetic in most species, including fish, favoring immune responses mediated by soluble immunomodulatory factors such as serotonin and the availability of nutrients against infectious processes. Francisella noatunensis coexist with fish such as Eleginops maclovinus, which raises questions about the susceptibility and immune response of the brain of E. maclovinus against Francisella.

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Introduction: Hospitalized patients with high respiratory technology dependency are increasingly common and result in lengthy stays in intensive care units. Strategies mitigating its impact have been scarcely described.

Objective: To describe a 6-year experience in a Pediatric Prolonged Mechanical Ventilation Unit.

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Purpose: To assess the cumulative risk of progression in glaucomatous eyes in the severe stage of disease.

Methods: This was a retrospective observational study. Patients that had severe damage in at least one eye, as defined by three criteria including a mean deviation of ≤ - 20 dB, were included.

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Introduction: Pediatric pulmonary rehabilitation is relevant in the management of chronic respiratory diseases. In Chile, it is provided only at certain hospitals. Objective.

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Introduction: The early diagnosis of Sleep Disordered Breathing (SDB) may allow proper intervention. Currently, polygraphy (PG) is a reliable and accessible alternative.

Objective: To describe and analyze the PG of children > 1 year old with suspicion of SDB.

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Introduction: An apparent life-threatening event (ALTE) is a frequent cause of hospitalization in infants. However, there is little evidence about the existence of a standardized approach to discover the main etiology, although a correct causal diagnosis can affect clinical evolution, hospital stay, and health resources. Objective: To determine the effects of a standardized diagnostic approach in infants admitted with ALTE.

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A commercial pyrethrum extract was used as a source of chrysanthemol for the synthesis of the citrophilus mealybug ( Pseudococcus calceolariae) sex pheromone. The chrysanthemic acid esters (pyrethrins I) were isolated and subsequently reduced to obtain chrysanthemol, which was used for ester pheromone synthesis. Field tests showed that the pheromone synthesized using plant-derived chrysanthemol was as attractive to male P.

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Physiological responses of plants to salinity stress requires the coordinated activation of many genes. A salt-induced gene was isolated from roots of the wild tomato species Solanum chilense and named SchRabGDI1 because it encodes a protein with high identity to GDP dissociation inhibitors of plants. These proteins are regulators of the RabGTPase cycle that play key roles in intracellular vesicular trafficking.

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Land-use change is a principal factor affecting riparian vegetation and river biodiversity. In Chile, land-use change has drastically intensified over the last decade, with native forests converted to exotic forest plantations and agricultural land. However, the effects thereof on aquatic ecosystems are not well understood.

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Unlabelled: Apnea and apparently lethal events have great etiological diversity thus complementary tests may help diagnosis. The aim of this study was to describe the results of polygraph studies of children under 3 months hospitalized with suspected apnea.

Patients And Methods: Retrospective case series.

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Parthenocarpic fruit development (PFD) reduces fruit yield and quality in grapevine. Parthenocarpic seedless berries arise from fruit set without effective fertilization due to defective pollen germination. PFD has been associated to micronutrient deficiency but the relation of this phenomenon with pollen polymorphism has not been reported before.

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We present a novel, insoluble, low-generation polyamidoamine (PAMAM)-based polymer. The monomer and polymer were characterized by fourier transform infrared spectroscopy, electrospray ionization mass spectrometry and thermogravimetric measurement, revealing that G0 acryloyl-terminated PAMAM were synthesized and polymerized using ammonium persulfate as an initiator, producing a high-density PAMAM derivative (PAMAM-HD). PAMAM-HD was tested for its ability to remove Na(I), K(I), Ca(II), Mg(II), Cu(II), Mn(II), Cd(II), Pb(II) and Zn(II) ions from acidic, neutral and basic aqueous solutions.

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The sorption of Fe(II) and Fe(III) by extracellular polymeric substances (EPS) of acidophilic bacteria Acidiphilium 3.2Sup(5) and Acidithiobacillus ferrooxidans, harvested from the ecosystem of the Tinto River (Huelva, Spain), was investigated. EPS from mixed cultures of both bacteria (EPS(mixed)) and pure cultures of A.

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Background: Zinc (Zn) deficiency is one of the most widespread mineral nutritional problems that affect normal development in plants. Because Zn cannot passively diffuse across cell membranes, it must be transported into intracellular compartments for all biological processes where Zn is required. Several members of the Zinc-regulated transporters, Iron-regulated transporter-like Protein (ZIP) gene family have been characterized in plants, and have shown to be involved in metal uptake and transport.

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Boron (B) is an essential micronutrient for normal development of roots, shoots and reproductive tissues in plants. Due to its role in the structure of rhamnogalacturonan II, a polysaccharide required for pollen tube growth, B deficiency has been associated with the occurrence of parthenocarpic seedless grapes in some varieties of Vitis vinifera L. Despite that, it is unclear how B is mobilized and accumulated in reproductive tissues.

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The concentrations of cadmium, lead, manganese and zinc were determined in the fish species Micropogonias manni captured in Budi Lake, Araucanía Region (Chile). The measurements were made by atomic absorption spectroscopy, and the analysis considered the sex, weight and size of the species; the representative samples were taken from the liver and muscle tissue. The method was validated using certified reference material (DOLT-1).

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Polyamidoamine (PAMAM) dendrimers and water-soluble 3-mercaptopropionic acid (MPA)-capped CdSe quantum dots (QDs) were combined to produce a new gel containing supramolecular complexes of QDs/PAMAM dendrimers. The formation of the QDs/PAMAM supramolecular complexes was confirmed by high resolution electron microscopy and Fourier transform infrared (FTIR) analyses. Molecular dynamics simulations corroborated the structure of the new QDs/PAMAM-based supramolecular compound.

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