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1.
Heredity (Edinb) ; 122(6): 893-905, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30542146

RESUMEN

Although low levels of genetic structure are expected in highly widespread species, geographical and/or ecological factors can limit species distributions and promote population structure and morphological differentiation. In order to determine the effects of geographical isolation on population genetic structure and wing morphology, 281 individuals of the cosmopolitan odonate Pantala flavescens were collected from four continental (Central and South America) and five insular sites (Polynesian islands and the Maldives). COI sequences and eight microsatellite loci were used to characterize genetic diversity and genetic structure between and within locations. Linear and geometric morphometry were used to evaluate differences in the size and shape of wings. Genetic analysis showed a global genetic difference between the continental and insular sites. American locations did not show genetic structure, even in locations separated by a distance of 5000 km. Easter Island showed the lowest values of genetic diversity (mainly mitochondrial diversity) and the highest values of genetic differences compared to other insular and continental sites. Individuals from Easter Island showed smaller forewings, a different abdomen length to thorax length ratio, and a different configuration of anal loop in the hindwings. Thus, the greater isolation, smaller area, and young geological age seem to have determined the genetic and morphological differences in P. flavescens of Easter Island, where selection could promote a loss of migratory behavior and may improve other life history traits, such as reproduction. This work provides new insight into how microevolutionary processes operate in isolated populations of cosmopolitan species.


Asunto(s)
Odonata/anatomía & histología , Odonata/genética , Animales , Variación Genética , Genética de Población , Islas , Repeticiones de Microsatélite , Odonata/crecimiento & desarrollo , Filogenia , América del Sur
2.
Artículo en Inglés | MEDLINE | ID: mdl-24798900

RESUMEN

Sequential treatments consisting in a chemical process followed by a conventional biological treatment, have been applied to remove mixtures of nine contaminants of pharmaceutical type spiked in a primary sedimentation effluent of a municipal wastewater. Combinations of ozone, UVA black light (BL) and Fe(III) or Fe3O4 catalysts constituted the chemical systems. Regardless of the Advanced Oxidation Process (AOP), the removal of pharmaceutical compounds was achieved in 1 h of reaction, while total organic carbon (TOC) only diminished between 3.4 and 6%. Among selected ozonation systems to be implemented before the biological treatment, the application of ozone alone in the pre-treatment stage is recommended due to the increase of the biodegradability observed. The application of ozone followed by the conventional biological treatment leads high TOC and COD removal rates, 60 and 61%, respectively, and allows the subsequent biological treatment works with shorter hydraulic residence time (HRT). Moreover, the influence of the application of AOPs before and after a conventional biological process was compared, concluding that the decision to take depends on the characterization of the initial wastewater with pharmaceutical compounds.


Asunto(s)
Óxido Ferrosoférrico/química , Hierro/química , Ozono/química , Preparaciones Farmacéuticas/química , Contaminantes Químicos del Agua/química , Catálisis , Ciudades , Oxidación-Reducción , Preparaciones Farmacéuticas/metabolismo , Aguas del Alcantarillado/microbiología , Rayos Ultravioleta , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/metabolismo
3.
Med Oral Patol Oral Cir Bucal ; 19(2): e99-e105, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-23986019

RESUMEN

OBJECTIVES: To describe the epidemiology of facial trauma injuries in a group of Chilean children aged 15 years or less. STUDY DESIGN: Retrospective study of case series. Between 2006 and 2009, clinical records of 293,090 patients were reviewed. Data of patients with trauma injuries to the face were collected and evaluated for: age, sex, day and month of hospital admission, cause of injury, anatomical location, type of injury and presence of associated injuries. RESULTS: A total of 7,617 patients with 8,944 injuries were found. Boy to girl ratio was 1,7:1. Preschool age children were most frequently affected. Main cause of injury were falls, soft tissue injuries the most common type of injury. Associated injuries occurred in 11% of cases. CONCLUSIONS: Facial trauma presents a significant frequency in the group of Chilean children studied. Preeschool age boys were prone to present facial trauma of mild severity associated to falls.


Asunto(s)
Traumatismos Faciales/epidemiología , Adolescente , Niño , Preescolar , Chile/epidemiología , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos , Factores de Tiempo
4.
Int Arch Allergy Immunol ; 160(1): 27-36, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22948082

RESUMEN

BACKGROUND: Airway viral infections provoke exacerbations of asthma and chronic obstructive pulmonary disease. B7-H1 is a costimulatory molecule that is implicated in an escape mechanism of viruses from host immune systems. This escape may be associated with the persistence of viral infection and lead to exacerbation of underlying diseases. We have shown that an analog of viral double-stranded RNA, polyinosinic-polycytidylic acid (poly IC), upregulated the expression of B7-H1 on airway epithelial cells, an effect which was corticosteroid-resistant. We investigated the effects of corticosteroids plus long-acting ß(2)-agonists (LABAs; fluticasone/salmeterol or budesonide/formoterol) on the expression of B7-H1. METHODS: BEAS-2B cells and primary airway epithelial cells were stimulated with poly IC or respiratory syncytial virus. The expression of B7-H1 was assessed by flow cytometry. RESULTS: Poly IC upregulated the expression of B7-H1, which was suppressed by high-concentration corticosteroids but not by LABAs. The upregulation was suppressed by very low-concentration corticosteroids when used in combination with LABAs. Their combination also suppressed the virus-induced upregulation of B7-H1. Poly IC stimulation induced the nuclear translocation of nuclear factor ĸB (NF-ĸB). Inhibitors of NF-ĸB activation prevented the poly IC-induced upregulation of B7-H1. Low-concentration corticosteroids in combination with LABAs enhanced the de novo induction of IĸBα, the endogenous inhibitor of NF-ĸB activation. CONCLUSIONS: Fluticasone/salmeterol or budesonide/formoterol attenuate the virus-associated upregulation of B7-H1 on airway epithelial cells via suppression of NF-ĸB activation.


Asunto(s)
Corticoesteroides/farmacología , Agonistas de Receptores Adrenérgicos beta 2/farmacología , Antígeno B7-H1/metabolismo , Poli I-C/farmacología , Mucosa Respiratoria/metabolismo , Albuterol/análogos & derivados , Albuterol/farmacología , Androstadienos/farmacología , Budesonida/farmacología , Línea Celular , Combinación de Medicamentos , Etanolaminas/farmacología , Combinación Fluticasona-Salmeterol , Fumarato de Formoterol , Humanos , Proteínas I-kappa B/metabolismo , Inhibidor NF-kappaB alfa , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Mucosa Respiratoria/patología , Mucosa Respiratoria/virología , Infecciones por Virus Sincitial Respiratorio/tratamiento farmacológico , Infecciones por Virus Sincitial Respiratorio/metabolismo , Virus Sincitiales Respiratorios/patogenicidad , Regulación hacia Arriba
5.
Allergol Immunopathol (Madr) ; 41(4): 233-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23141838

RESUMEN

BACKGROUND: There are no data on atmospheric pollen in Talca. In the present work, our aim is to describe the amount of pollen grain in the atmosphere of the city of Talca likely to cause pollinosis of its inhabitants. METHODS: A volumetric Hirst sampler (Burkard seven-day recording device) was used to study pollen levels. It was placed in the centre of Talca from May 2007 to April 2008. RESULTS: The highest airborne presence of pollen, as measured in weekly averages, was Platanus acerifolia with a maximum weekly daily average of 203 grains/m³ registered during September and October. The second highest was Acer pseudoplatanus with a maximum weekly daily average of 116 grains/m³. Populus spp. had a maximum weekly daily average 103 grains/m³. Olea europaea reached 19 grains/m³ in November. Grasses presented high levels of pollen counts with a maximum weekly daily average of 27 grains/m³ from the end of August until the end of January. Pollens of Plantago spp. Rumex acetosella and Chenopodium spp. had a similar distribution and were present from October to April with maximum weekly daily average of 7 grains/m³, 7 grains/m³ and 3 grains/m³ respectively. Significant concentrations of Ambrosia artemisiifolia were detected from February until April. CONCLUSION: The population of Talca was exposed to high concentrations of allergenic pollen, such as P. acerifolia, A. pseudoplatanus, and grasses in the months of August through November. The detection of O. europaea and A. artemisiifolia is important as these are emergent pollens in the city of Talca. Aerobiological monitoring will provide the community with reliable information about the level of allergenic pollens, improving treatment and quality of life of patients with respiratory allergy.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminación del Aire/estadística & datos numéricos , Alérgenos/análisis , Cycadopsida , Monitoreo del Ambiente , Magnoliopsida , Polen , Contaminación del Aire/análisis , Chile , Monitoreo del Ambiente/instrumentación , Monitoreo del Ambiente/métodos , Estaciones del Año
6.
Braz J Biol ; 84: e254095, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35019103

RESUMEN

In northern central Chile, ephemeral pools constitute shallow isolated water bodies with a favourable habitat for fauna adapted to seasonal changes. Based on the limited knowledge about the fauna-particularly insects-associated to these ecosystems, the objective of this study was to characterize the richness, composition, structure and similarity of the insect communities associated with ephemeral pools in Huentelauquén (29º S, Coquimbo Region, Chile). By using pitfall traps, 10,762 individuals were captured, represented by 7 orders, 27 families, and 51 species. Coleoptera and Hymenoptera were the best represented orders, with Neuroptera, Orthoptera and Plecoptera being poorly represented groups. The non-parametric estimators evaluated showed wealth values above those observed for all the studied pools, and their accumulation curves suggest the existence of an incomplete species inventory in the studied community. Additionally, the hierarchical and ordering analysis showed groupings of pools located in the northwest and southeast of Huentelauquén. Preliminarily we found a negative correlation between the area of the pools and the richness (species) and abundance of insects. Additional studies (on other arthropod groups and other seasons of the year) could provide a better understanding of the local processes of extinction and colonization of the species inhabiting these fragile coastal environments.


Asunto(s)
Escarabajos , Ecosistema , Animales , Biodiversidad , Chile , Humanos , Insectos , Estaciones del Año
7.
Front Physiol ; 13: 769924, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35450164

RESUMEN

Gestational Diabetes Mellitus (GDM) is a highly prevalent maternal pathology characterized by maternal glucose intolerance during pregnancy that is, associated with severe complications for both mother and offspring. Several risk factors have been related to GDM; one of the most important among them is genetic predisposition. Numerous single nucleotide polymorphisms (SNPs) in genes that act at different levels on various tissues, could cause changes in the expression levels and activity of proteins, which result in glucose and insulin metabolism dysfunction. In this review, we describe various SNPs; which according to literature, increase the risk of developing GDM. These SNPs include: (1) those associated with transcription factors that regulate insulin production and excretion, such as rs7903146 (TCF7L2) and rs5015480 (HHEX); (2) others that cause a decrease in protective hormones against insulin resistance such as rs2241766 (ADIPOQ) and rs6257 (SHBG); (3) SNPs that cause modifications in membrane proteins, generating dysfunction in insulin signaling or cell transport in the case of rs5443 (GNB3) and rs2237892 (KCNQ1); (4) those associated with enzymes such as rs225014 (DIO2) and rs9939609 (FTO) which cause an impaired metabolism, resulting in an insulin resistance state; and (5) other polymorphisms, those are associated with growth factors such as rs2146323 (VEGFA) and rs755622 (MIF) which could cause changes in the expression levels of these proteins, producing endothelial dysfunction and an increase of pro-inflammatory cytokines, characteristic on GDM. While the pathophysiological mechanism is unclear, this review describes various potential effects of these polymorphisms on the predisposition to develop GDM.

8.
J Biochem Mol Toxicol ; 25(6): 393-403, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21692149

RESUMEN

Toxin phospholipases-D present in the venom of Loxosceles spiders is the principal responsible for local and systemic effects observed in the loxoscelism. In this study, we describe the cloning, expression, functional evaluation, and potential biotechnological application of cDNAs, which code for two new phospholipase D isoforms, LIPLD1 and LIPLD2, of the spider Loxosceles laeta. The recombinant protein rLIPLD1 had hydrolytic activity on sphingomyelin and in vitro hemolytic activity on human red blood cells, whereas rLIPLD2 was inactive. The purified recombinant proteins and the venom are recognized by polyclonal anti-rLIPLD1 and rLIPLD2 sera produced in animals and conferred immunoprotection against the venom. These new isoforms reinforce the importance of the multigene family of phospholipases-D present in Loxosceles spiders. A highly immunogenic inactive isoform such as rLIPLD2 raises important expectation for its use as a potential immunogenic inducer of the immunoprotective response to the toxic action of the venom of Loxosceles laeta.


Asunto(s)
Biotecnología , Fosfolipasa D , Venenos de Araña/enzimología , Arañas/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Células Cultivadas , Clonación Molecular , Secuencia Conservada , ADN Complementario/genética , Eritrocitos/efectos de los fármacos , Hemólisis/efectos de los fármacos , Humanos , Isoenzimas , Datos de Secuencia Molecular , Fosfolipasa D/genética , Fosfolipasa D/inmunología , Fosfolipasa D/farmacología , Hidrolasas Diéster Fosfóricas/toxicidad , Filogenia , Alineación de Secuencia , Especificidad de la Especie , Venenos de Araña/toxicidad , Arañas/inmunología , Arañas/metabolismo
9.
Science ; 289(5484): 1557-60, 2000 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-10968792

RESUMEN

The existence of a general relation between population density and body size in animal assemblages has been debated because of known biases and ambiguities in the published data and data handling. Using new comprehensive data sets from two geographically separated stream communities that encompass 448 and 260 invertebrate taxa with a wide range of body sizes, we show that an inverse proportionality between density and body size is a consistent feature in these communities. The scaling across taxa is not statistically different between the two systems, indicating a convergent pattern of communities. Variation in the regression slope among different taxonomic groups indicates that these communities are not governed universally by a single ecological or energetic rule.


Asunto(s)
Ecosistema , Invertebrados/anatomía & histología , Invertebrados/fisiología , Análisis de Varianza , Animales , Austria , Constitución Corporal , Agua Dulce , Matemática , Densidad de Población , Análisis de Regresión , Gales
10.
Braz. j. biol ; 842024.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469317

RESUMEN

Abstract In northern central Chile, ephemeral pools constitute shallow isolated water bodies with a favourable habitat for fauna adapted to seasonal changes. Based on the limited knowledge about the faunaparticularly insectsassociated to these ecosystems, the objective of this study was to characterize the richness, composition, structure and similarity of the insect communities associated with ephemeral pools in Huentelauquén (29º S, Coquimbo Region, Chile). By using pitfall traps, 10,762 individuals were captured, represented by 7 orders, 27 families, and 51 species. Coleoptera and Hymenoptera were the best represented orders, with Neuroptera, Orthoptera and Plecoptera being poorly represented groups. The non-parametric estimators evaluated showed wealth values above those observed for all the studied pools, and their accumulation curves suggest the existence of an incomplete species inventory in the studied community. Additionally, the hierarchical and ordering analysis showed groupings of pools located in the northwest and southeast of Huentelauquén. Preliminarily we found a negative correlation between the area of the pools and the richness (species) and abundance of insects. Additional studies (on other arthropod groups and other seasons of the year) could provide a better understanding of the local processes of extinction and colonization of the species inhabiting these fragile coastal environments.


Resumo No norte central do Chile, lagoas efêmeras constituem corpos de água isolados e pouco profundos, com um habitat favorável para a fauna adaptada as mudanças sazonais que as zonas úmidas estão sujeitas. Com relação a estes ecossistemas, sabe-se pouco sobre sua fauna, principalmente a de insetos. O objetivo do presente estudo foi caracterizar a riqueza, composição, estrutura e similaridade das comunidades de insetos que habitam as lagoas temporárias de Huentelauquén (29º S, Região de Coquimbo, Chile). Usando armadilhas de interceptação, se capturou um total de 10.762 indivíduos, pertencentes a 7 ordens, 27 famílias e 51 espécies. Coleoptera e Hymenoptera foram as ordens mais representativas, enquanto Neuroptera, Orthoptera e Plecoptera foram grupos pouco representativos. Os estimadores não paramétricos avaliados mostraram valores de riqueza superiores ao observados para todas as lagoas estudadas, e suas curvas de acumulação parecem indicar que o inventario da comunidade estudada está incompleto. A análise hierárquica e de ordenamento revelou agrupamentos de lagoas correspondentes a zona nordeste e sudeste de Huentelauquén. Preliminarmente encontramos uma correlação negativa entre a área de lagoas efêmeras e a riqueza (espécies) e abundância de insetos. É necessário realizar estudos adicionais (sobre outros grupos de artrópodes e em outras estações do ano) para melhor compreensão dos processos locais de extinção e colonização das espécies que habitam estes frágeis ambientes costeiros estudados.

11.
Braz. j. biol ; 84: e254095, 2024. tab, graf
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1355860

RESUMEN

Abstract In northern central Chile, ephemeral pools constitute shallow isolated water bodies with a favourable habitat for fauna adapted to seasonal changes. Based on the limited knowledge about the fauna—particularly insects—associated to these ecosystems, the objective of this study was to characterize the richness, composition, structure and similarity of the insect communities associated with ephemeral pools in Huentelauquén (29º S, Coquimbo Region, Chile). By using pitfall traps, 10,762 individuals were captured, represented by 7 orders, 27 families, and 51 species. Coleoptera and Hymenoptera were the best represented orders, with Neuroptera, Orthoptera and Plecoptera being poorly represented groups. The non-parametric estimators evaluated showed wealth values above those observed for all the studied pools, and their accumulation curves suggest the existence of an incomplete species inventory in the studied community. Additionally, the hierarchical and ordering analysis showed groupings of pools located in the northwest and southeast of Huentelauquén. Preliminarily we found a negative correlation between the area of the pools and the richness (species) and abundance of insects. Additional studies (on other arthropod groups and other seasons of the year) could provide a better understanding of the local processes of extinction and colonization of the species inhabiting these fragile coastal environments.


Resumo No norte central do Chile, lagoas efêmeras constituem corpos de água isolados e pouco profundos, com um habitat favorável para a fauna adaptada as mudanças sazonais que as zonas úmidas estão sujeitas. Com relação a estes ecossistemas, sabe-se pouco sobre sua fauna, principalmente a de insetos. O objetivo do presente estudo foi caracterizar a riqueza, composição, estrutura e similaridade das comunidades de insetos que habitam as lagoas temporárias de Huentelauquén (29º S, Região de Coquimbo, Chile). Usando armadilhas de interceptação, se capturou um total de 10.762 indivíduos, pertencentes a 7 ordens, 27 famílias e 51 espécies. Coleoptera e Hymenoptera foram as ordens mais representativas, enquanto Neuroptera, Orthoptera e Plecoptera foram grupos pouco representativos. Os estimadores não paramétricos avaliados mostraram valores de riqueza superiores ao observados para todas as lagoas estudadas, e suas curvas de acumulação parecem indicar que o inventario da comunidade estudada está incompleto. A análise hierárquica e de ordenamento revelou agrupamentos de lagoas correspondentes a zona nordeste e sudeste de Huentelauquén. Preliminarmente encontramos uma correlação negativa entre a área de lagoas efêmeras e a riqueza (espécies) e abundância de insetos. É necessário realizar estudos adicionais (sobre outros grupos de artrópodes e em outras estações do ano) para melhor compreensão dos processos locais de extinção e colonização das espécies que habitam estes frágeis ambientes costeiros estudados.


Asunto(s)
Humanos , Animales , Escarabajos , Ecosistema , Estaciones del Año , Chile , Biodiversidad , Insectos
12.
Rev. ANACEM (Impresa) ; 15(1): 72-78, 2021.
Artículo en Español | LILACS | ID: biblio-1281220

RESUMEN

La incontinencia urinaria de urgencia corresponde a la pérdida involuntaria de orina, cuya causa es presumida multifactorial: hiperactividad del detrusor, hipersensibilidad vesical y distensibilidad reducida del detrusor. Esta patología es bastante frecuente tanto en Chile como en el mundo, con una prevalencia local entre 10% y 15%, a su vez genera un gran impacto en el bienestar físico, mental y socioeconómico del paciente. El diagnóstico es clínico, con apoyo en el uroanálisis y su tratamiento de primera línea puede ser realizado en APS. En cuanto al tratamiento existen tanto terapias no farmacológicas como farmacológicas; correspondiendo las técnicas de reentrenamiento vesical, los cambios de estilo de vida y los fármacos anticolinérgicos a tratamientos efectivos de primera línea. Existen, además, otros fármacos que pueden ser utilizados para el tratamiento de la IUU, cuya evidencia será igualmente revisada en este artículo.


Urge incontinence is defined as an involuntary leakage of urine, presumably with a multifactorial cause: detrusor overactivity, bladder hypersensibility and a reduced bladder compliance. It's a common disease worldwide, with local studies reporting a prevalence around 10-15%, causing a great impact in the physical, mental and socioeconomic well-being of the affected patients. Diagnosis is mainly based on the clinical history, supporting it with laboratory tests to rule out other conditions, and uncomplicated cases can be treated and followed in a primary care setting. There are pharmacologic and non-pharmacologic therapies, being healthy lifestyles changes, bladder retraining programs and anticholinergic drugs the first line of treatment. Additional pharmacologic treatments will be revised in this article.


Asunto(s)
Humanos , Femenino , Atención Primaria de Salud , Calidad de Vida , Incontinencia Urinaria de Urgencia/diagnóstico , Incontinencia Urinaria de Urgencia/tratamiento farmacológico , Incontinencia Urinaria/epidemiología , Urología , Incontinencia Urinaria de Urgencia/terapia , Incontinencia Urinaria de Urgencia/epidemiología
13.
Clin Cancer Res ; 2(11): 1851-7, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9816140

RESUMEN

The recombinant oncotoxin AR209 [e23(Fv)PE38KDEL; formerly OLX-209] was developed to treat neoplasia that expresses the c-erbB-2 (HER-2/neu) protein product p185(erbB-2). The AR209 compound contains a single-chain antibody domain specific for p185(erbB-2), coupled with a portion of the Pseudomonas exotoxin. The drug has been shown to be effective in inhibiting cells that overexpress erbB-2 due to gene amplification and in cells that do not contain amplified erbB-2 but express slightly higher levels of the protein than normal cells do. To test the efficacy of AR209 on human lung tumors, athymic nude mice were inoculated intrathoracically with a cell line derived from a poorly differentiated lung adenocarcinoma. This cell line, termed 201T, expresses moderately elevated levels of p185(erbB-2) 7.6-fold over normal bronchial epithelium. Mice treated with i.v. injections of AR209 for 5 weeks after orthotopic tumor implantation had smaller tumors and in 20% of cases showed no evidence of disease. The data from this study indicate that AR209 may be an effective treatment for patients with non-small cell lung cancers that express p185(erbB-2).


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Inmunotoxinas/uso terapéutico , Neoplasias Pulmonares/tratamiento farmacológico , Receptor ErbB-2/antagonistas & inhibidores , Animales , Anticuerpos , Carcinoma de Pulmón de Células no Pequeñas/diagnóstico por imagen , Carcinoma de Pulmón de Células no Pequeñas/patología , Exotoxinas , Humanos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Radiografía , Proteínas Recombinantes de Fusión/uso terapéutico , Proteínas Recombinantes/uso terapéutico , Anticuerpos de Cadena Única , Células Tumorales Cultivadas
14.
J Colloid Interface Sci ; 283(2): 503-12, 2005 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-15721926

RESUMEN

The impact of ozonation on textural and chemical surface characteristics of two granular activated carbons (GAC), namely F400 and AQ40, and their ability to adsorb phenol (P), p-nitrophenol (PNP), and p-chlorophenol (PCP) from aqueous solutions have been studied. The porous structure of the ozone-treated carbons remained practically unchanged with regard to the virgin GAC. However, important modifications of the chemical surface and hydrophobicity were observed from FTIR spectroscopy, pH titrations, and determination of pH(PZC). As a rule, the ozone treatment at either room temperature (i.e., about 25 degrees C) or 100 degrees C gave rise to acidic surface oxygen groups (SOG). At 25 degrees C primarily carboxylic acids were formed while a more homogeneous distribution of carboxylic, lactonic, hydroxyl, and carbonyl groups was obtained at 100 degrees C. The experimental isotherms for phenolic compounds on both GAC were analyzed using the Langmuir model. Dispersive interactions between pi electrons of the ring of the aromatics and those of the carbon basal planes were thought to be the primary forces responsible for the physical adsorption whereas oxidative coupling of phenolic compounds catalyzed by basic SOG was a major cause of irreversible adsorption. The exposure of both GAC to ozone at room temperature decreased their ability to adsorb P, PNP, and PCP. However, when ozone was applied at 100 degrees C adsorption was not prevented but in some cases (P and PNP on F400) the adsorption process was even enhanced.


Asunto(s)
Carbono/química , Ozono/química , Fenoles/química , Adsorción , Oxidación-Reducción , Soluciones/química , Propiedades de Superficie , Temperatura , Agua/química
15.
Gastroenterol. latinoam ; 31(1): 9-20, mayo 2020. tab, ilus
Artículo en Español | LILACS, Inca | ID: biblio-1103076

RESUMEN

The outbreak of COVID-19 disease has recently spread from its original place in Wuhan, Hubei province, China, to the entire world, and has been declared to be a pandemic by the World Health Organization in March 2020. All countries in America, in particular Chile, show an important increase in COVID-19 cases and deaths. The clinical manifestations of COVID-19 are a broad spectrum, from asymptomatic mild disease, to severe respiratory failure, shock, multiorgan dysfunction and death. Thus, high clinical suspicion and appropriate structure risk stratification are needed. Health care teams in endoscopy units, are at an increased risk of infection by COVID-19 from inhalation of droplets, mucosae contact, probably contamination due to contact with stools. Endoscopic aerosolized associated infections have also been reported. Different societies' recommendations, have recently placed digestive endoscopy (especially upper) among the high risk aerosol generating procedures (AGPs). In addition, live virus has been found in patient stools. On top of this, the infected health professionals may transmit the infection to their patients. Health care infection prevention and control (HCIPC), has been shown to be effective in assuring the safety of both health care personnel and patients. This is not limited to the correct use of personal protective equipment (PPE), but is based on a clear, detailed and well communicated HCIPC strategy, risk stratification, use of PPE, and careful interventions in patients with moderate and high risk of COVID-19. A conscientious approach regarding limited resources is important, as the simultaneous outbreak in all countries heavily affects the availability of health supplies. The Chilean Gastroenterology Society (SChGE) and Digestive Endoscopy Association of Chile (ACHED) are joining to provide continued updated guidance in order to assure the highest level of protection against COVID-19, for both patients and health care workers. This guideline will be updated online as needed.


El brote de la enfermedad denominada COVID-19, se ha extendido desde su origen en Wuhan, provincia de Hubei, China, a todo el mundo. La Organización Mundial de la Salud lo declaró pandemia en marzo de 2020. Todos los países de América, en especial Chile, presentan incremento de casos y fallecidos. Las manifestaciones clínicas de COVID-19 van desde una enfermedad leve, hasta insuficiencia respiratoria severa, shock, disfunción orgánica y muerte. Se necesita una alta sospecha clínica y una adecuada estratificación del riesgo. El equipo de salud en las unidades de endoscopia, tiene un mayor riesgo de COVID-19 que otras unidades clínicas y de apoyo diagnóstico, dada la mayor exposición a inhalación de gotas, contacto posible con mucosas y contaminación por contacto con deposiciones. Recomendaciones de diferentes sociedades colocan la endoscopia digestiva (especialmente la esofagogastroscopia o endoscopia digestiva alta, EDA) entre los procedimientos generadores de aerosoles (PGA) de alto riesgo. Además, se han encontrado virus viables en las deposiciones de los pacientes. Potencialmente, los profesionales de la salud infectados podrían contagiar a los pacientes. Se ha demostrado que la prevención y control de infecciones asociadas a la atención de salud (IAAS), son efectivos para garantizar la seguridad tanto del personal de salud, como de los pacientes. Esto no es solamente el correcto uso del equipo de protección personal (EPP), sino que se basa en una clara estrategia de IAAS, bien comunicada, con estratificación de riesgo, uso de EPP e intervenciones correctas en pacientes con riesgo moderado y alto. Es relevante un enfoque sobre los limitados recursos, dado la simultaneidad del brote en todos los países, que afecta la disponibilidad de insumos. La Sociedad Chilena de Gastroenterología (SChGE) y la Asociación Chilena de Endoscopia Digestiva (ACHED) publican esta guía actualizada para apoyar las buenas prácticas contra COVID-19, tanto para pacientes como para el equipo de salud. Esta guía podrá tener actualizaciones según avance la información disponible.


Asunto(s)
Humanos , Neumonía Viral/prevención & control , Endoscopía del Sistema Digestivo/normas , Infecciones por Coronavirus/prevención & control , Betacoronavirus , Neumonía Viral/epidemiología , Factores de Riesgo , Control de Infecciones/métodos , Guías de Práctica Clínica como Asunto , Infecciones por Coronavirus/epidemiología , Pandemias , Unidades Hospitalarias/normas
16.
Am J Clin Nutr ; 29(4): 358-65, 1976 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1266785

RESUMEN

Histological methods (Golgi-Cox and Nissl) were used to study the maturation of the large pyramidal cells of layer V of the occipital cortex in malnourished rats (according to the method of Araya et al.). The main alterations were observed in pyramidal cells of cortical alyer V; These showed a decrease of the number and span of dendritic basilar processes. An increase in cell density was also observed in this layer. We assume that malnutrition during this period of development provokes a derangement which disturbs the process of neuron differentiation, with effects that probably are permanent.


Asunto(s)
Trastornos Nutricionales/fisiopatología , Lóbulo Occipital/crecimiento & desarrollo , Animales , Animales Recién Nacidos , Diferenciación Celular , Dendritas/ultraestructura , Femenino , Tamaño de la Camada , Masculino , Neuronas/citología , Lóbulo Occipital/patología , Embarazo , Ratas
17.
Cancer Epidemiol Biomarkers Prev ; 6(7): 547-50, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9232344

RESUMEN

The relationship between p53 gene expression and DNA content in advanced gallbladder carcinoma was studied. Fifty-three cases of advanced gallbladder carcinoma (45 primary tumors and 8 metastases) were analyzed, p53 protein expression was determined by immunohistochemistry, DNA content was measured by cytophotometric techniques. Study subjects included 45 (85%) female and 8 male patients, with an overall mean age of 58.6 years. Positive staining for p53 protein was observed in 27 (51%) cases. In subserosal tumors, the expression was significantly less than that in tumors that reached the serosa (P = 0.01). Twenty-nine (55%) cases were diploid and 24 were aneuploid. Sixty-seven % of primary tumors were diploid, whereas 87% of metastases showed an aneuploid DNA content. Both diploid and aneuploid tumors were positive for the p53 protein in the same proportion, and p53 was also expressed equally in both primary and secondary tumors. In advanced gallbladder carcinoma, the expression of the p53 gene was earlier than the accumulation of abnormal quantities of chromosomal DNA in the tumor cells. The determination of these events as markers in preneoplastic lesions is warranted in gallbladder carcinogenesis.


Asunto(s)
Adenocarcinoma/genética , ADN de Neoplasias/genética , Neoplasias de la Vesícula Biliar/genética , Ploidias , Proteína p53 Supresora de Tumor/genética , Adenocarcinoma/patología , Adulto , Anciano , Aneuploidia , Biomarcadores de Tumor/genética , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/patología , Diploidia , Femenino , Vesícula Biliar/patología , Neoplasias de la Vesícula Biliar/patología , Regulación Neoplásica de la Expresión Génica/fisiología , Humanos , Masculino , Persona de Mediana Edad
18.
Mol Biochem Parasitol ; 65(1): 161-9, 1994 May.
Artículo en Inglés | MEDLINE | ID: mdl-7935622

RESUMEN

We have cloned and sequenced a cDNA clone coding for a metacyclic trypomastigote-specific surface glycoprotein with a molecular mass of 82 kDa (MTS-gp82). By immunoblotting and immunoprecipitation, antibodies against the recombinant protein recognized an 82-kDa protein of metacyclic trypomastigotes, without any detectable reaction towards amastigotes, epimastigotes or tissue culture-derived trypomastigotes. The insert of the MTS-gp82 cDNA clone strongly hybridized with a single 2.2-kb metacyclic trypomastigote mRNA, suggesting that the steady-state levels of mRNAs for MTS-gp82 are developmentally regulated. MTS-gp82 is encoded by a multigene family whose members are distributed in several chromosomes. Sequence analysis revealed 40-56% identity at amino acid level between MTS-gp82 and members of Trypanosoma cruzi gp85/sialidase family (TSA-1, Tt34c1, SA85-1.1). MTS-gp82 showed several amino acid motifs that are characteristic of gp85/sialidase family, such as the Asp box (SxDxGxTW), the subterminal (VTVxNVFLYNR) motif and the putative GPI-anchor sequence. On the basis of its structural features, the MTS-gp82 gene could be included in the T. cruzi gp85/sialidase family, but constituting a distinct group which is preferentially expressed in metacyclic trypomastigotes.


Asunto(s)
Antígenos de Protozoos/genética , Antígenos de Superficie/genética , Genes Protozoarios , Trypanosoma cruzi/genética , Trypanosoma cruzi/inmunología , Glicoproteínas Variantes de Superficie de Trypanosoma , Secuencia de Aminoácidos , Animales , Antígenos de Protozoos/química , Antígenos de Superficie/química , Clonación Molecular , ADN Complementario/genética , ADN Protozoario/genética , Glicoproteínas/genética , Datos de Secuencia Molecular , Peso Molecular , Familia de Multigenes , Neuraminidasa/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Protozoario/genética , ARN Protozoario/metabolismo , Homología de Secuencia de Aminoácido , Trypanosoma cruzi/crecimiento & desarrollo
19.
Int J Parasitol ; 31(3): 259-64, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11226452

RESUMEN

We report here the isolation and characterisation of genomic and cDNA clones encoding a Serine-, Alanine-, and Proline-rich protein (SAP) of Trypanosoma cruzi metacyclic trypomastigotes. The deduced peptides translated from these clones were characterised by a high content of residues of alanine, proline, serine, glycine, valine, and threonine distributed in several repeats: P(2-4), S(2-3), A(2-3), AS, SA, PA, AP, SP, PS, and TP. The repeats are partially homologous to the serine-, alanine-, and proline-containing motifs of Leishmania major and Leishmania mexicana proteophosphoglycans. Genes coding for SAP are part of a polymorphic family whose members are linked to members of gp85/sialidase and mucin-like gene families. This is consistent with the hypothesis that this genetic organisation could be a means by which T. cruzi co-ordinates the expression of major surface proteins.


Asunto(s)
Genoma de Protozoos , Proteínas Protozoarias/genética , Trypanosoma cruzi/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Clonación Molecular , ADN Complementario , Datos de Secuencia Molecular , Familia de Multigenes , Proteínas Protozoarias/química , Proteínas Protozoarias/aislamiento & purificación , Proteínas Protozoarias/metabolismo , Análisis de Secuencia de ADN , Trypanosoma cruzi/crecimiento & desarrollo , Trypanosoma cruzi/metabolismo
20.
Surgery ; 125(4): 385-95, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10216529

RESUMEN

BACKGROUND: The protective effects of heat-shock protein (hsp) in rat small intestinal warm ischemia-reperfusion (I/R) injury are poorly understood. METHODS: Hsp-73 expression was induced in rat small intestine with use of sodium arsenite injected (6 mg/kg) through a catheter cannulated into the left common carotid artery 24 hours before ischemia (group 1). In the control group an equal volume of phosphate-buffered saline solution was injected (group 2). To block the induction of hsp-73 expression, sodium arsenate and quercetin (5 mg/kg) were injected (group 3). RESULTS: The mean peak plasma levels of tumor necrosis factor-alpha and cytokine-induced neutrophil chemoattractant after reperfusion were lower in group 1 than in group 2. The tissue myeloperoxidase activity after reperfusion was lower in group 1 than in group 2. The mean peak plasma level of interleukin-10 after reperfusion was higher in group 1 than in group 2. The induction of hsp-73 expression reduced the synthesis of nitric oxide and the magnitude of the small intestinal warm I/R injury. The results in group 3 were similar to those in group 2. CONCLUSION: Hsp-73 protects against small intestinal warm I/R injury by inhibiting the synthesis of inflammatory cytokines and the activation of neutrophils and by accelerating the synthesis of anti-inflammatory cytokines.


Asunto(s)
Quimiocinas CXC , Proteínas de Choque Térmico/fisiología , Péptidos y Proteínas de Señalización Intercelular , Intestino Delgado/irrigación sanguínea , Intestino Delgado/cirugía , Daño por Reperfusión/prevención & control , Animales , Arsenitos/farmacología , Western Blotting , Factores Quimiotácticos/biosíntesis , Factores Quimiotácticos/sangre , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Ensayo de Inmunoadsorción Enzimática , Inhibidores de Crecimiento/biosíntesis , Inhibidores de Crecimiento/sangre , Sustancias de Crecimiento/biosíntesis , Sustancias de Crecimiento/sangre , Proteínas de Choque Térmico/análisis , Calor , Interleucina-10/biosíntesis , Interleucina-10/sangre , Mucosa Intestinal/irrigación sanguínea , Mucosa Intestinal/enzimología , Mucosa Intestinal/cirugía , Intestino Delgado/enzimología , Masculino , Óxido Nítrico/biosíntesis , Óxido Nítrico/sangre , Peroxidasa/metabolismo , Quercetina/farmacología , Ratas , Ratas Endogámicas Lew , Daño por Reperfusión/inducido químicamente , Compuestos de Sodio/farmacología , Factor de Necrosis Tumoral alfa/biosíntesis , Factor de Necrosis Tumoral alfa/metabolismo
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