Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 62
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
New Phytol ; 242(2): 727-743, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38009920

RESUMEN

Poales are one of the most species-rich, ecologically and economically important orders of plants and often characterise open habitats, enabled by unique suites of traits. We test six hypotheses regarding the evolution and assembly of Poales in open and closed habitats throughout the world, and examine whether diversification patterns demonstrate parallel evolution. We sampled 42% of Poales species and obtained taxonomic and biogeographic data from the World Checklist of Vascular Plants database, which was combined with open/closed habitat data scored by taxonomic experts. A dated supertree of Poales was constructed. We integrated spatial phylogenetics with regionalisation analyses, historical biogeography and ancestral state estimations. Diversification in Poales and assembly of open and closed habitats result from dynamic evolutionary processes that vary across lineages, time and space, most prominently in tropical and southern latitudes. Our results reveal parallel and recurrent patterns of habitat and trait transitions in the species-rich families Poaceae and Cyperaceae. Smaller families display unique and often divergent evolutionary trajectories. The Poales have achieved global dominance via parallel evolution in open habitats, with notable, spatially and phylogenetically restricted divergences into strictly closed habitats.


Asunto(s)
Ecosistema , Poaceae , Filogenia , Evolución Biológica
2.
Neurobiol Learn Mem ; 212: 107937, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38735637

RESUMEN

Systemic manipulations that enhance dopamine (DA) transmission around the time of fear extinction can strengthen fear extinction and reduce conditioned fear relapse. Prior studies investigating the brain regions where DA augments fear extinction focus on targets of mesolimbic and mesocortical DA systems originating in the ventral tegmental area, given the role of these DA neurons in prediction error. The dorsal striatum (DS), a primary target of the nigrostriatal DA system originating in the substantia nigra (SN), is implicated in behaviors beyond its canonical role in movement, such as reward and punishment, goal-directed action, and stimulus-response associations, but whether DS DA contributes to fear extinction is unknown. We have observed that chemogenetic stimulation of SN DA neurons during fear extinction prevents the return of fear in contexts different from the extinction context, a form of relapse called renewal. This effect of SN DA stimulation is mimicked by a DA D1 receptor (D1R) agonist injected into the DS, thus implicating DS DA in fear extinction. Different DS subregions subserve unique functions of the DS, but it is unclear where in the DS D1R agonist acts during fear extinction to reduce renewal. Furthermore, although fear extinction increases neural activity in DS subregions, whether neural activity in DS subregions is causally involved in fear extinction is unknown. To explore the role of DS subregions in fear extinction, adult, male Long-Evans rats received microinjections of either the D1R agonist SKF38393 or a cocktail consisting of GABAA/GABAB receptor agonists muscimol/baclofen selectively into either dorsomedial (DMS) or dorsolateral (DLS) DS subregions immediately prior to fear extinction, and extinction retention and renewal were subsequently assessed drug-free. While increasing D1R signaling in the DMS during fear extinction did not impact fear extinction retention or renewal, DMS inactivation reduced later renewal. In contrast, DLS inactivation had no effect on fear extinction retention or renewal but increasing D1R signaling in the DLS during extinction reduced fear renewal. These data suggest that DMS and DLS activity during fear extinction can have opposing effects on later fear renewal, with the DMS promoting renewal and the DLS opposing renewal. Mechanisms through which the DS could influence the contextual gating of fear extinction are discussed.


Asunto(s)
Cuerpo Estriado , Extinción Psicológica , Miedo , Receptores de Dopamina D1 , Animales , Miedo/fisiología , Miedo/efectos de los fármacos , Extinción Psicológica/efectos de los fármacos , Extinción Psicológica/fisiología , Masculino , Ratas , Cuerpo Estriado/efectos de los fármacos , Cuerpo Estriado/fisiología , Cuerpo Estriado/metabolismo , Receptores de Dopamina D1/fisiología , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D1/antagonistas & inhibidores , Agonistas de Dopamina/farmacología , Condicionamiento Clásico/efectos de los fármacos , Condicionamiento Clásico/fisiología , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/fisiología , Sustancia Negra/efectos de los fármacos , Sustancia Negra/fisiología , Ratas Long-Evans , Dopamina/metabolismo , Dopamina/fisiología
3.
Int J Mol Sci ; 25(12)2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38928430

RESUMEN

Arsenic compounds have been used as therapeutic alternatives for several diseases including cancer. In the following work, we obtained arsenic nanoparticles (AsNPs) produced by an anaerobic bacterium from the Salar de Ascotán, in northern Chile, and evaluated their effects on the human oral squamous carcinoma cell line OECM-1. Resazurin reduction assays were carried out on these cells using 1-100 µM of AsNPs, finding a concentration-dependent reduction in cell viability that was not observed for the non-tumoral gastric mucosa-derived cell line GES-1. To establish if these effects were associated with apoptosis induction, markers like Bcl2, Bax, and cleaved caspase 3 were analyzed via Western blot, executor caspases 3/7 via luminometry, and DNA fragmentation was analyzed by TUNEL assay, using 100 µM cisplatin as a positive control. OECM-1 cells treated with AsNPs showed an induction of both extrinsic and intrinsic apoptotic pathways, which can be explained by a significant decrease in P-Akt/Akt and P-ERK/ERK relative protein ratios, and an increase in both PTEN and p53 mRNA levels and Bit-1 relative protein levels. These results suggest a prospective mechanism of action for AsNPs that involves a potential interaction with extracellular matrix (ECM) components that reduces cell attachment and subsequently triggers anoikis, an anchorage-dependent type of apoptosis.


Asunto(s)
Anoicis , Apoptosis , Arsénico , Nanopartículas , Humanos , Anoicis/efectos de los fármacos , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Nanopartículas/química , Arsénico/farmacología , Arsénico/toxicidad , Supervivencia Celular/efectos de los fármacos , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Caspasa 3/metabolismo , Transducción de Señal/efectos de los fármacos , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo
4.
Mol Phylogenet Evol ; 181: 107714, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36708940

RESUMEN

Anchored Hybrid Enrichment (AHE) is a tool for capturing orthologous regions of the nuclear genome shared in low or single copy across lineages. Despite the increasing number of studies using this method, its usefulness to estimate relationships at deeper taxonomic levels in plants has not been fully explored. Here we present a proof of concept about the performance of nuclear loci obtained with AHE to infer phylogenetic relationships and explore the use of gene sampling schemes to estimate divergence times in Asterales. We recovered low-copy nuclear loci using the AHE method from herbarium material and silica-preserved samples. Maximum likelihood, Bayesian inference, and coalescence approaches were used to reconstruct phylogenomic relationships. Dating analyses were conducted under a multispecies coalescent approach by jointly inferring species tree and divergence times with random gene sampling schemes and multiple calibrations. We recovered 403 low-copy nuclear loci for 63 species representing nine out of eleven families of Asterales. Phylogenetic hypotheses were congruent among the applied methods and previously published results. Analyses with concatenated datasets were strongly supported, but coalescence-based analyses showed low support for the phylogenetic position of families Argophyllaceae and Alseuosmiaceae. Estimated family ages were congruent among gene sampling schemes, with the mean age for Asterales around 130 Myr. Our study documents the usefulness of AHE for resolving phylogenetic relationships at deep phylogenetic levels in Asterales. Observed phylogenetic inconsistencies were possibly due to the non-inclusion of families Phellinceae and Pentaphragmataceae. Random gene sampling schemes produced consistent age estimates with coalescence and species tree relaxed clock approaches.


Asunto(s)
Magnoliopsida , Filogenia , Magnoliopsida/genética , Teorema de Bayes , Genoma , Núcleo Celular/genética
5.
Rev Med Chil ; 150(10): 1275-1282, 2022 Oct.
Artículo en Español | MEDLINE | ID: mdl-37358085

RESUMEN

BACKGROUND: Fibrous Dysplasia/McCune-Albright Syndrome (FD/MAS) is characterized by a spectrum of manifestations that may include fibrous dysplasia of bone and multiple endocrinopathies. AIM: To describe the clinical spectrum, the study and follow-up of patients with FD/MAS cared at our institution. MATERIAL AND METHODS: Review of medical records of 12 pediatric and adult patients (11 women) who met the clinical and genetic diagnostic criteria for FD/ MAS. RESULTS: The patients' mean age at diagnosis was 4.9 ± 5.5 years. The most common initial clinical manifestation was peripheral precocious puberty (PPP) in 67% of patients and 75% had café-au-lait spots. Fibrous dysplasia was present in 75% of patients and the mean age at diagnosis was 7.9 ± 4.7 years. Ten patients had a bone scintigraphy, with an age at the first examination that varied between 2 and 38 years of age. The most frequent location of dysplasia was craniofacial and appendicular. No patient had a recorded history of cholestasis, hepatitis, or pancreatitis. In four patients, a genetic study was performed that was positive for the pathogenic variant of guanine nucleotide binding protein, alpha stimulating (GNAS). CONCLUSIONS: These patients demonstrate the variable nature of the clinical presentation and study of FD/MAS. It is essential to increase the index of diagnostic suspicion and adherence to international recommendations.


Asunto(s)
Displasia Fibrosa Ósea , Displasia Fibrosa Poliostótica , Pubertad Precoz , Adulto , Humanos , Niño , Femenino , Preescolar , Adolescente , Adulto Joven , Displasia Fibrosa Poliostótica/diagnóstico por imagen , Displasia Fibrosa Poliostótica/genética , Chile/epidemiología , Displasia Fibrosa Ósea/diagnóstico por imagen , Pubertad Precoz/etiología , Pubertad Precoz/genética , Manchas Café con Leche/genética
6.
J Dairy Sci ; 103(1): 228-241, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31704005

RESUMEN

In humid temperate regions, forage turnip (Brassica rapa ssp. rapa) and forage rape (Brassica napus ssp. biennis) are common fodder crops used for dairy cattle during the summer season. However, there is little scientific information regarding the use of brassicas and their effect on the fatty acid (FA) profile in blood, milk, and milk products. The aim of this study was to evaluate the effect of forage brassica supplementation in dairy cows on the FA profile of blood plasma, milk, and cheese, and on the sensory characteristics of Chanco and Ricotta cheeses. Twelve multiparous dairy cows (Holstein Friesian) were housed and submitted to a 3 × 3 replicated (n = 3) Latin square design with 3 treatments (control, turnip, or rape) in 3 periods of 21 d each (14 d of diet adaptation and 7 d of measurements). The control diet consisted of 16.20 kg of grass silage (Lolium perenne), 2.25 kg of soybean bran, and 2.25 kg of commercial concentrate, all on a dry matter (DM) basis. In the treatments with forage brassicas, 24.15% of the total DM was replaced by turnip or rape; thus, they consisted of 12.25 kg of silage, 2.25 kg of soybean bran, 1.2 kg of concentrate, and 5 kg of turnip or rape (DM basis). A principal components analysis was performed on the results of the cheese sensory evaluation. Supplementation with turnip or rape modified the profile of FA in blood plasma and milk, increasing the saturated fraction, mainly short- and medium-chain FA, and decreasing the mono- and polyunsaturated FA. In the sensory evaluation, diet did not affect any of the 18 attributes evaluated. However, in the principal components analysis, cheeses made with milk from animals fed turnip and rape were differentiated by increased odor, flavor, spiciness, bitterness, and acidity. Overall, brassicas can be used as an alternative forage source with no negative effects on sensory characteristics of cheeses.


Asunto(s)
Brassica napus , Brassica rapa , Bovinos/fisiología , Queso/análisis , Ácidos Grasos/análisis , Ensilaje/análisis , Animales , Chile , Dieta/veterinaria , Suplementos Dietéticos/análisis , Femenino , Lolium , Glycine max
7.
BMC Evol Biol ; 19(1): 28, 2019 01 21.
Artículo en Inglés | MEDLINE | ID: mdl-30665356

RESUMEN

BACKGROUND: The polyamine oxidases (PAOs) catabolize the oxidative deamination of the polyamines (PAs) spermine (Spm) and spermidine (Spd). Most of the phylogenetic studies performed to analyze the plant PAO family took into account only a limited number and/or taxonomic representation of plant PAOs sequences. RESULTS: Here, we constructed a plant PAO protein sequence database and identified four subfamilies. Subfamily PAO back conversion 1 (PAObc1) was present on every lineage included in these analyses, suggesting that BC-type PAOs might play an important role in plants, despite its precise function is unknown. Subfamily PAObc2 was exclusively present in vascular plants, suggesting that t-Spm oxidase activity might play an important role in the development of the vascular system. The only terminal catabolism (TC) PAO subfamily (subfamily PAOtc) was lost in Superasterids but it was present in all other land plants. This indicated that the TC-type reactions are fundamental for land plants and that their function could being taken over by other enzymes in Superasterids. Subfamily PAObc3 was the result of a gene duplication event preceding Angiosperm diversification, followed by a gene extinction in Monocots. Differential conserved protein motifs were found for each subfamily of plant PAOs. The automatic assignment using these motifs was found to be comparable to the assignment by rough clustering performed on this work. CONCLUSIONS: The results presented in this work revealed that plant PAO family is bigger than previously conceived. Also, they delineate important background information for future specific structure-function and evolutionary investigations and lay a foundation for the deeper characterization of each plant PAO subfamily.


Asunto(s)
Modelos Moleculares , Oxidorreductasas actuantes sobre Donantes de Grupo CH-NH/química , Plantas/enzimología , Análisis de Secuencia de Proteína , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Dominio Catalítico , Análisis por Conglomerados , Bases de Datos de Proteínas , Filogenia , Dominios Proteicos , Homología Estructural de Proteína , Poliamino Oxidasa
8.
Mol Microbiol ; 110(4): 596-615, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30192418

RESUMEN

ExoS/ChvI two-component signaling in the nitrogen-fixing α-proteobacterium Sinorhizobium meliloti is required for symbiosis and regulates exopolysaccharide production, motility, cell envelope integrity and nutrient utilization in free-living bacteria. However, identification of many ExoS/ChvI direct transcriptional target genes has remained elusive. Here, we performed chromatin immunoprecipitation followed by microarray analysis (chIP-chip) to globally identify DNA regions bound by ChvI protein in S. meliloti. We then performed qRT-PCR with chvI mutant strains to test ChvI-dependent expression of genes downstream of the ChvI-bound DNA regions. We identified 64 direct target genes of ChvI, including exoY, rem and chvI itself. We also identified ChvI direct target candidates, like exoR, that are likely controlled by additional regulators. Analysis of upstream sequences from the 64 ChvI direct target genes identified a 15 bp-long consensus sequence. Using electrophoretic mobility shift assays and transcriptional fusions with exoY, SMb21440, SMc00084, SMc01580, chvI, and ropB1, we demonstrated this consensus sequence is important for ChvI binding to DNA and transcription of ChvI direct target genes. Thus, we have comprehensively identified ChvI regulon genes and a 'ChvI box' bound by ChvI. Many ChvI direct target genes may influence the cell envelope, consistent with the critical role of ExoS/ChvI in growth and microbe-host interactions.


Asunto(s)
Proteínas Bacterianas/metabolismo , Regulación Bacteriana de la Expresión Génica/genética , Sinorhizobium meliloti/genética , Sinorhizobium meliloti/metabolismo , Factores de Transcripción/metabolismo , Proteínas Bacterianas/genética , Sitios de Unión/genética , Proteínas de Unión al ADN/genética , Genoma Bacteriano/genética , Glucosiltransferasas/genética , Unión Proteica/genética , Transducción de Señal , Simbiosis/genética , Factores de Transcripción/genética , Transcripción Genética/genética
9.
Rev Med Chil ; 146(1): 116-121, 2018 Jan.
Artículo en Español | MEDLINE | ID: mdl-29806686

RESUMEN

Pseudohypoparathyroidism (PHP) is a group of rare genetic disorders that share organ targeted resistance to the action of parathyroid hormone (PTH) as a common feature. Biochemically, they may present with hypocalcemia, hyperphosphatemia and elevated PTH. Some forms present with a specific phenotype: short stature, round facies, short neck, obesity, brachydactyly and subcutaneous calcifications, called Albrigth's Hereditary Osteodystrophy (AHO). This spectrum of disorders are caused by several alterations in the gene coding for the alpha subunit of the G protein (GNAS): an ubiquitous signaling protein that mediates the action of numerous hormones such as PTH, TSH, gonadotropins, and ACTH, among others. According to their inheritance with maternal or paternal imprinting, they may manifest in a diversity of clinical forms. Although most commonly diagnosed during childhood, PHP may manifest clinically during adolescence or early adulthood. We report two late presenting cases of pseudohypoparathyroidism. A 21-year-old female with biochemical abnormalities characteristic of pseudohypoparathyroidism who was misdiagnosed as epilepsy and a 13-year-old boy with the classic AHO phenotype but without alterations in phospho-calcium metabolism, compatible with pseudopseudohypoparathyrodism.


Asunto(s)
Seudohipoparatiroidismo/diagnóstico por imagen , Adolescente , Femenino , Humanos , Masculino , Factores de Tiempo , Tomografía Computarizada por Rayos X , Adulto Joven
10.
Mol Phylogenet Evol ; 114: 415-425, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28606445

RESUMEN

The number of species recognized in section Asperae of the flowering plant genus Hydrangea differs widely between subsequent revisions. This variation is largely centered around the H. aspera species complex, with numbers of recognized species varying from one to nearly a dozen. Despite indications of molecular variation in this complex, no sequence-based species delimitation methods have been employed to evaluate the primarily morphology-based species boundaries. In the present study, a multi-locus coalescent-based approach to species delimitation is employed in order to identify separate evolutionary lines within H. sect. Asperae, using four chloroplast and four nuclear molecular markers. Eight lineages were recovered within the focal group, of which five correspond with named morphotypes. The other three lineages illustrate types of conflict between molecular species delimitation and traditional morphology-based taxonomy. One molecular lineage comprises two named morphotypes, which possibly diverged recently enough to not have developed sufficient molecular divergence. A second conflict is found in H. strigosa. This morphotype is recovered as a separate lineage when occurring in geographic isolation, but when occurring in sympatry with two other morphotypes (H. aspera and H. robusta), the coalescent species delimitation lumps these taxa into a single putative species.


Asunto(s)
Hydrangea/clasificación , Teorema de Bayes , Cloroplastos/clasificación , Cloroplastos/genética , ADN de Plantas/química , ADN de Plantas/aislamiento & purificación , ADN de Plantas/metabolismo , Hydrangea/anatomía & histología , Hydrangea/genética , Microscopía Electrónica de Rastreo , Filogenia , Hojas de la Planta/anatomía & histología , Hojas de la Planta/química , Quinona Reductasas/clasificación , Quinona Reductasas/genética , ARN de Transferencia de Valina/clasificación , ARN de Transferencia de Valina/genética
11.
Mol Phylogenet Evol ; 117: 111-123, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28535985

RESUMEN

Recalcitrant relationships are characterized by very short internodes that can be found among shallow and deep phylogenetic scales all over the tree of life. Adding large amounts of presumably informative sequences, while decreasing systematic error, has been suggested as a possible approach to increase phylogenetic resolution. The development of enrichment strategies, coupled with next generation sequencing, resulted in a cost-effective way to facilitate the reconstruction of recalcitrant relationships. By applying the anchored hybrid enrichment (AHE) genome partitioning strategy to Aristolochia using an universal angiosperm probe set, we obtained 231-233 out of 517 single or low copy nuclear loci originally contained in the enrichment kit, resulting in a total alignment length of 154,756bp to 160,150bp. Since Aristolochia (Piperales; magnoliids) is distantly related to any angiosperm species whose genome has been used for the plant AHE probe design (Amborella trichopoda being the closest), it serves as a proof of universality for this probe set. Aristolochia comprises approximately 500 species grouped in several clades (OTUs), whose relationships to each other are partially unknown. Previous phylogenetic studies have shown that these lineages branched deep in time and in quick succession, seen as short-deep internodes. Short-shallow internodes are also characteristic of some Aristolochia lineages such as Aristolochia subsection Pentandrae, a clade of presumably recent diversification. This subsection is here included to test the performance of AHE at species level. Filtering and subsampling loci using the phylogenetic informativeness method resolves several recalcitrant phylogenetic relationships within Aristolochia. By assuming different ploidy levels during bioinformatics processing of raw data, first hints are obtained that polyploidization contributed to the evolution of Aristolochia. Phylogenetic results are discussed in the light of current systematics and morphology.


Asunto(s)
Aristolochia/clasificación , Aristolochia/genética , Filogenia , Alelos , Genoma de Planta/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Ploidias
12.
Mol Phylogenet Evol ; 117: 124-134, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28189618

RESUMEN

We conducted a pilot study using Anchored Hybrid Enrichment to resolve relationships among a mostly Neotropical sage lineage that may have undergone a recent evolutionary radiation. Conventional markers (ITS, trnL-trnF and trnH-psbA) have not been able to resolve the relationships among species nor within portions of the backbone of the lineage. We sampled 12 representative species of subgenus Calosphace and included one species of Salvia's s.l. closest relative, Lepechinia, as outgroup. Hybrid enrichment and sequencing were successful, yielding 448 alignments of individual loci with an average length of 704bp. The performance of the phylogenomic data in phylogenetic reconstruction was superior to that of conventional markers, increasing both support and resolution. Because the captured loci vary in the amount of net phylogenetic informativeness at different phylogenetic depths, these data are promising in phylogenetic reconstruction of this group and likely other lineages within Lamiales. However, special attention should be placed on the amount of phylogenetic noise that the data could potentially contain. A prior exploration step using phylogenetic informativeness profiles to detect loci with sites with disproportionately high substitution rates (showing "phantom" spikes) and, if required, the ensuing filtering of the problematic data is recommended. In our dataset, filtering resulted in increased support and resolution for the shallow nodes in maximum likelihood phylogenetic trees resulting from concatenated analyses of all the loci. Additionally, it is expected that an increase in sampling (loci and taxa) will aid in resolving weakly supported, short deep internal branches.


Asunto(s)
Filogenia , Salvia/genética , Sitios Genéticos/genética , Marcadores Genéticos/genética , Proyectos Piloto , Análisis de Secuencia de ADN
13.
Rev Panam Salud Publica ; 41: e67, 2017 Jun 08.
Artículo en Español | MEDLINE | ID: mdl-28614477

RESUMEN

OBJECTIVE: Characterize the implementation process, barriers, and facilitators of evidence-based recommendations in the context of developing clinical practice guidelines (CPGs) generated by the Ministry of Health of Chile, in order to make proposals to optimize the process. METHODS: Qualitative "action-oriented research" study. Nineteen semi-structured interviews were conducted and nine discussion groups were organized at various levels of the Chilean public health system. The analysis was conducted using Atlas.ti® software and manually, in a content analysis framework, by categorizing and coding information according to pre-specified dimensions and with the inclusion of emerging categories where relevant. RESULTS: The main challenge mentioned with regard to implementing recommendations is the lack of an explicit and structured process. Actors in the health system recognize difficulties specific to the context in which the recommendations are followed. In this unprecedented institutional review, participants suggested a series of strategies that could be implemented to overcome these challenges, presented in a management flow chart optimized for the development and implementation of CPGs. This process has raised awareness of the importance of implementing CPGs in Chile. CONCLUSION: After characterizing the implementation process, barriers, and facilitators, a plan to implement recommendations was developed in order to guide and monitor the process. It would facilitate the implementation of strategies and the introduction of improvements to the CPG development process if key informants inside and outside of the Ministry of Health were included in the review process. Studies of this kind should be conducted with physicians and patients in order to complement the collected information.


Asunto(s)
Adhesión a Directriz/estadística & datos numéricos , Chile , Atención a la Salud , Investigación Cualitativa
14.
Cutan Ocul Toxicol ; 36(1): 12-18, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27055483

RESUMEN

Isaria fumosorosea (formerly Paecilomyces fumosoroseus) is an entomopathogenic fungus that has been proposed as a low risk environmental alternative to the use of chemical insecticides to control agricultural pests and disease vectors. Although there are some mycoinsecticides already being marketed in many countries, not all their biosafety protocols have been published. The acute dermal toxicity test in an animal model is one in a series of biosafety protocols that must be developed, in order to provide information on health hazards, while taking into consideration the periods that the workers are in direct contact with the microbial agent when applied for the control of pests. For this test, we used I. fumosorosea monospore culture EH-506/3, isolated in Mexico from the Bemisia tabaci whitefly, applying a dose of 2 g/kg of animal body weight, on the shaved skin of 16 New Zealand rabbits, with an exposure time of 24 h. Clinical observations were conducted to evaluate the presence of erythema, edema and other alterations in the skin, as well as the behavior and health of the animals, for a period of 14 days. None of the rabbits showed clinical signs of any disease and their body weight corresponded to the expected weight for a healthy rabbit. The test showed no inflammatory reactions in the skin, supporting the safety of a single dose of this fungus in dermal exposure. Therefore, these data support the safety of I. fumosorosea EH-506/3 when applied to the skin.


Asunto(s)
Agentes de Control Biológico/toxicidad , Hypocreales , Paecilomyces , Animales , Femenino , Masculino , Conejos , Piel/anatomía & histología , Pruebas Cutáneas , Pruebas de Toxicidad Aguda
15.
Rev Med Chil ; 145(11): 1463-1470, 2017 Nov.
Artículo en Español | MEDLINE | ID: mdl-29664529

RESUMEN

The Ministry of Health of Chile, aiming to improve the quality of clinical practice guidelines, gradually incorporated the GRADE system (Grading of Recommendations, Assessment, Development and Evaluation) to develop evidence based recommendations. This system summarizes and evaluates the certainty of the available evidence. It moves from evidence to decision in a systematic and transparent manner, based on four main dimensions: balance between benefits and harms, certainty of evidence, patient's values and preferences and use of resources. The GRADE system produces strong and conditional recommendations. Strong recommendations provide confidence that the favorable consequences of an intervention clearly outweigh the adverse consequences, or vice versa. These recommendations apply to a broad range of patients and circumstances. Conditional recommendations, however, indicate that there is a close balance between favorable and unfavorable consequences of the intervention, there is uncertainty in the magnitude of benefits or adverse effects, there is uncertainty or variability in values and preferences of individuals or costs are not justified. These recommendations apply to many patients, but not all of them: ideally they should be discussed with each person. To achieve a better implementation of the recommendations made with GRADE methodology, health professionals should know the meaning of strong and conditional recommendations and they should be able to critically assess of them.


Asunto(s)
Medicina Basada en la Evidencia/instrumentación , Guías de Práctica Clínica como Asunto/normas , Adulto , Antivirales/uso terapéutico , Toma de Decisiones , Personal de Salud , Humanos , Gripe Humana/tratamiento farmacológico , Oseltamivir/uso terapéutico
16.
BMC Evol Biol ; 15: 132, 2015 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-26141718

RESUMEN

BACKGROUND: Identifying orthologous molecular markers that potentially resolve relationships at and below species level has been a major challenge in molecular phylogenetics over the past decade. Non-coding regions of nuclear low- or single-copy markers are a vast and promising source of data providing information for shallow-scale phylogenetics. Taking advantage of public transcriptome data from the One Thousand Plant Project (1KP), we developed a genome-scale mining strategy for recovering potentially orthologous single-copy markers to address low-scale phylogenetics. Our marker design targeted the amplification of intron-rich nuclear single-copy regions from genomic DNA. As a case study we used Hydrangea section Cornidia, one of the most recently diverged lineages within Hydrangeaceae (Cornales), for comparing the performance of three of these nuclear markers to other "fast" evolving plastid markers. RESULTS: Our data mining and filtering process retrieved 73 putative nuclear single-copy genes which are potentially useful for resolving phylogenetic relationships at a range of divergence depths within Cornales. The three assessed nuclear markers showed considerably more phylogenetic signal for shallow evolutionary depths than conventional plastid markers. Phylogenetic signal in plastid markers increased less markedly towards deeper evolutionary divergences. Potential phylogenetic noise introduced by nuclear markers was lower than their respective phylogenetic signal across all evolutionary depths. In contrast, plastid markers showed higher probabilities for introducing phylogenetic noise than signal at the deepest evolutionary divergences within the tribe Hydrangeeae (Hydrangeaceae). CONCLUSIONS: While nuclear single-copy markers are highly informative for shallow evolutionary depths without introducing phylogenetic noise, plastid markers might be more appropriate for resolving deeper-level divergences such as the backbone relationships of the Hydrangeaceae family and deeper, at which non-coding parts of nuclear markers could potentially introduce noise due to elevated rates of evolution. The herein developed and demonstrated transcriptome based mining strategy has a great potential for the design of novel and highly informative nuclear markers for a range of plant groups and evolutionary scales.


Asunto(s)
Genes de Plantas , Hydrangea/genética , Minería de Datos , Evolución Molecular , Hydrangea/clasificación , Filogenia , Plastidios , Transcriptoma
17.
J Clin Periodontol ; 42(10): 900-7, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26356350

RESUMEN

AIM: To describe the prevalence, severity and extension of clinical attachment loss (CAL) and to study the predictors in 15- to 19-year-old adolescents from high schools in the Latin America. MATERIALS AND METHODS: A cross-sectional, epidemiological study was performed. The sample included 1070 high school adolescents 15-19 years of age from Santiago de Chile (Chile), Buenos Aires, Córdoba, Mendoza (Argentina), Montevideo (Uruguay), Quito (Ecuador) and Medellín (Colombia). Calibrated examiners performed full mouth, six sites per tooth clinical examination. RESULTS: There was a response rate of 100%. The prevalence of CAL ≥3 mm in ≥1 site was 32.6%, probing pocket depth ≥4 mm was 59.3% and bleeding on probing (BoP) ≥25% was 28.6%. The logistic regression analysis adjusted for cities revealed that smoking (OR = 1.6), attending public school (OR = 2.3) and having a BoP ≥25% (OR = 4.2) were positively associated with CAL ≥3 mm in ≥ 1 site. CONCLUSION: Clinical attachment loss was prevalent in Latin America adolescents and it is associated with smoking, attendance public school and BoP.


Asunto(s)
Pérdida de la Inserción Periodontal/epidemiología , Adolescente , Estudios Transversales , Atención Odontológica , Femenino , Humanos , América Latina/epidemiología , Masculino , Prevalencia , Fumar/epidemiología , Adulto Joven
19.
J Fungi (Basel) ; 10(4)2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38667940

RESUMEN

In this study, molecular typing using Randomly Amplified Polymorphic DNA (RAPD-PCR) was conducted on 16 original isolates of Metarhizium acridum obtained from locusts (Schistocerca piceifrons ssp. piceifrons.) in Mexico (MX). The analysis included reference strains of the genus Metarhizium sourced from various geographical regions. The isolates were identified by phenotypic (macro and micromorphology) and genotypic methods (RAPD-PCR and Amplified Fragment Length Polymorphisms (AFLP), through a multidimensional analysis of principal coordinates (PCoA) and a minimum spanning network (MST). Subsequently, Sequences-Characterized Amplified Region (SCAR) markers were developed for the molecular detection of M. acridum, these markers were chosen from polymorphic patterns obtained with 14 primers via RAPD-PCR. Phenotypic and genotypic characterization identified the MX isolates as M. acridum. Of all the polymorphic patterns obtained, only OPA04 and OPA05 were chosen, which presented species-specific bands for M. acridum, and further utilized to create SCAR markers through cloning and sequencing of the specific bands. The specificity of these two markers was confirmed via Southern hybridization. The SCAR markers (Ma-160OPA-05 and Ma-151OPA-04) exhibit remarkable sensitivity, detecting down to less than 0.1 ng, as well as high specificity, as evidenced by their inability to cross-amplify or generate amplification with DNAs from other strains of Metarhizium (as Metarhizium anisopliae) or different genera of entomopathogenic fungi (Cordyceps fumosorosea and Akanthomyces lecanii). These SCAR markers yield readily detectable results, showcasing high reproducibility. They serve as a valuable tool, especially in field applications.

20.
Mol Phylogenet Evol ; 66(1): 233-42, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23063487

RESUMEN

In evolutionary biology appropriate marker selection for the reconstruction of solid phylogenetic hypotheses is fundamental. One of the most challenging tasks addresses the appropriate choice of genomic regions in studies of closely related species. Robust phylogenetic frameworks are central to studies dealing with questions ranging from evolutionary and conservation biology, biogeography to plant breeding. Phylogenetic informativeness profiles provide a quantitative measure of the phylogenetic signal in markers and therefore a method for locus prioritization. The present work profiles phylogenetic informativeness of mostly non-coding chloroplast regions in an angiosperm lineage of closely related species: the popular ornamental tribe Hydrangeeae (Hydrangeaceae, Cornales, Asterids). A recent phylogenetic study denoted a case of resolution contrast between the two strongly supported clades within tribe Hydrangeeae. We evaluate the phylogenetic signal of 13 highly variable plastid markers for estimating relationships within and among the currently recognized monophyletic groups of this tribe. A selection of combined loci based on their phylogenetic informativeness retrieved more robust phylogenetic hypotheses than simply combining individual markers performing best with respect to resolution, nodal support and accuracy or those presenting the highest number of parsimony informative characters. We propose the rpl32-ndhF intergenic spacer (IGS), trnV-ndhC IGS, trnL-rpl32 IGS, psbT-petB region and ndhA intron as the best candidates for future phylogenetic studies in Hydrangeeae and potentially in other Asterids. We also contrasted the phylogenetic informativeness of coded indels against substitutions concluding that, despite their low phylogenetic informativeness, coded indels provide additional phylogenetic signal that is nearly free of noise. Phylogenetic relationships obtained from our total combined analyses showed improved resolution and nodal support with respect to recently published results.


Asunto(s)
ADN de Cloroplastos/genética , Hydrangeaceae/clasificación , Filogenia , Análisis de Secuencia de ADN/métodos , ADN de Plantas/genética , Marcadores Genéticos , Hydrangeaceae/genética , Modelos Genéticos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA