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1.
Mar Environ Res ; 195: 106366, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38277814

RESUMEN

The producer of paralytic shellfish toxin (PST), Alexandrium catenella, is one of the main generators of HABs in the coasts of Chile. Its presence produces ecological and economic damage, directly affecting filter-feeding organisms, and indirectly to other organism through the trophic chain. The objective of this research was to identify the effect of a toxic diet on the energetic and reproductive parameters of the carnivorous snail Chorus giganteus. Two groups of snails were used, one fed with toxic prey (bivalves fed with A. catenella), and the other fed with non-toxic prey. Both treatments were maintained under these conditions for 63 days, then, elemental composition (C, N) and energy content were estimated, and fecundity parameters were analyzed. The results indicate that snails fed with toxic prey had a lower percentage of C and C/N ratio. The energy content was significantly lower in intoxicated snails. Regarding fecundity parameters, a higher number of egg-masses were produced by toxic snails, however, only 62% of these showed embryonic development, with 57% hatching success. A negative relationship was identified between the mean PST concentration, quantified in snails, and the number of egg-masses produced per aquarium. In the aquarium where the snails had highest average PST concentration (1200 ± 820 µg STX.2HCL eq. Kg-1) there was no oviposition, while egg-masses were only produced by snails in aquaria where the average concentration did not exceed 360 ± 160 µg STX.2HCL eq. Kg-1. It is likely that, with low levels of accumulated PST, C. giganteus activates its oviposition process as a response to toxin-induced stress, generating a higher energy expenditure supported by a redirection of its reserves. However, when the intoxication presents higher levels, the reproductive process could be inhibited, similar to what has been identified in other molluscs.


Asunto(s)
Bivalvos , Dinoflagelados , Gastrópodos , Animales , Toxinas Marinas/toxicidad , Mariscos/análisis , Ingestión de Alimentos
2.
Mar Environ Res ; 180: 105735, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36058088

RESUMEN

Alexandrium catenella, one of the most common harmful microalgae observed in southern Chile, produces paralytic shellfish toxins, which can affect many organisms throughout the trophic chain. This research evaluated how paralytic shellfish toxins affected the principal bioenergetic constituents and fatty acids composition of the carnivorous snail Chorus giganteus. Snails were separated into a "toxic" group that was fed the toxic clam Mulinia edulis (which was previously fed A. catenella), and a "non-toxic" group, fed non-toxic clams. Both groups were kept under these conditions for 63 days. Our results indicated no difference in the ingestion rate of toxic versus non-toxic snails; however, a higher protein level was identified in toxic snails. The total lipid content proved to be no different in toxic versus non-toxic snails; although, an effect of the toxic diet on the fatty acid profile of C. giganteus was observed. High levels of essential polyunsaturated fatty acids, especially docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) in toxic snails, were identified. Our results suggest that exposure to paralytic shellfish toxins, through diet, may cause changes in the biochemical composition of C. giganteus, which may have a subsequent impact on its energetic physiology.


Asunto(s)
Bivalvos , Dinoflagelados , Gastrópodos , Animales , Bivalvos/química , Metabolismo Energético , Explotaciones Pesqueras , Gastrópodos/fisiología , Toxinas Marinas/metabolismo , Toxinas Marinas/toxicidad , Mariscos
3.
Encephale ; 47(4): 291-298, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33551123

RESUMEN

OBJECTIVES: The aim of this study was to adapt and validate the Schizophrenia Caregiver's Quality of Life Questionnaire (S-CGQoL) for use in the Hispanic-American population from the caregiver's perspective. METHODS: A cross-sectional instrumental model was used, with a sample of 253 caregivers of patients suffering of Schizophrenia in Bolivia, Peru and Chile. The psychometric properties of the S-CGQoL were tested through construct validity, reliability and some aspects of external validity. In addition, in order to assess the nature of the different items across the three countries, a Differential Performance Analysis (DPA) was conducted. RESULTS: A confirmatory factor analysis showed that the scale structure was well correlated to the initial structure of the QoL-MDS. The results confirmed the existence of adequate reliability indicators (α>.70 and ω>.80) and the absence of FIDs supporting the invariance of item calibrations among the three Latin American countries. CONCLUSIONS: The adaptation and validation of the S-CGQoL questionnaire demonstrate adequate psychometric properties to assess the quality of life of caregivers in samples of middle-income countries in Latin America.


Asunto(s)
Calidad de Vida , Esquizofrenia , Cuidadores , Comparación Transcultural , Estudios Transversales , Humanos , América Latina , Psicometría , Reproducibilidad de los Resultados , Encuestas y Cuestionarios
4.
Rev Chil Pediatr ; 85(5): 561-8, 2014 Oct.
Artículo en Español | MEDLINE | ID: mdl-25697432

RESUMEN

OBJECTIVE: To describe capabilities and difficulties in emotional adjustment experienced by children living in the Chilean Aymara city of Arica. PATIENTS AND METHOD: 610 students between 5th and 8th grade, in addition to their parents and teachers were surveyed using the Strengths and Difficulties Questionnaire (SDQ), comparing Aymara children to those without indigenous heritage. 25 items divided into five scales were evaluated: Emotional, behavioral problems, hyperactivity, relationship problems with peers and prosocial behaviors, classifying the respondents into three levels, Normal, Border and Abnormal. RESULTS: There were no significant differences among the groups studied, where discrepancies in almost all cases show a slight effect (d≥|0.2|). Also, no relevant effects were observed regarding the type of assessor on the assessment of each dimension. Despite this, it was observed that Aymara children showed lower scores than their peers in "behavioral problems" according to their teachers, but this difference was also mild (partial η2>0.01). CONCLUSIONS: Aymara Children showed similar strengths and difficulties than non-Aymara students in situations that require emotional adjustment.


Asunto(s)
Conducta Infantil/psicología , Ajuste Emocional , Indígenas Sudamericanos/psicología , Adolescente , Niño , Chile , Docentes , Femenino , Humanos , Masculino , Padres , Encuestas y Cuestionarios
5.
Ter. psicol ; 26(1): 133-141, jul. 2008. tab
Artículo en Español | LILACS | ID: lil-520613

RESUMEN

En una muestra de 436 adolescentes pertenecientes a establecimientos privados, subvencionados y municipalizados de la ciudad de Antofagasta, se evalúan las propiedades psicométricas de la versión en castellano del cuestionario Kiddo-Kindl, destinado a evaluar la calidad de vida en la adolescencia en torno a seis dimensiones. Se encuentra una consistencia interna similar a la reportada en España y una estructura factorial aceptable. Los varones presentan una mejor evaluación de la calidad de vida en algunas dimensiones, al igual que los que autoevalúan como sanos por aquellos que se autodefinen como enfermos. En términos generales este conjunto de dimensiones es buen instrumento de tamizaje para evaluar la calidad de vida de los adolescentes, sin embargo, debe profundizarse el estudio sobre su aplicación en grupos específicos y afinar su estructura factorial, esto último, cuestión relevante para su uso generalizado.


The psychometric properties of the Kiddo-Kindl in Spanish are evaluated in a sample of 436 adolescents from private, semi-private, and public schools of the city of Antofagasta. This instrument is designed to evaluate adolescent quality of life in six dimensions. The internal consistency of the instrument is similar to what has been reported in Spain, with an acceptable factorial structure. Males have a better evaluation of their quality of life in some dimensions, as well as those who consider themselves healthy in comparison to those who consider themselves unhealthy. In general terms, the totality of dimensions are seen adequate as a general diagnostic of adolescent's quality of life. However, it is recommended to investigate the use of this instrument with specific groups, and to improve its factorial structure, which is an important question for its generalized use.


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Calidad de Vida , Encuestas y Cuestionarios , Salud Mental , Salud del Adolescente , Análisis Factorial , Análisis de Varianza , Autoimagen , Chile , Estado de Salud , Factores Sexuales , Psicometría , Relaciones Interpersonales
6.
J Ethnopharmacol ; 103(2): 297-301, 2006 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-16310995

RESUMEN

The antibacterial activity of Haplopappus uncinatus is attributed to a new clerodane diterpenoid, 18-acetoxy-cis-cleroda-3-en-15-oic acid (10 betaH, 16 xi 19 beta, 17beta, 20 alpha form) (1), isolated as a major component from the resinous exudates of its twigs and leaves, together with the inactive 3,5-dihydroxy-6,7,3',4'-tetramethoxyflavone, n-alkanes and a few sesquiterpenoids.


Asunto(s)
Antiinfecciosos/química , Diterpenos/química , Haplopappus , Extractos Vegetales/química , Antiinfecciosos/aislamiento & purificación , Diterpenos/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/aislamiento & purificación , Relación Estructura-Actividad
7.
Fitoterapia ; 74(6): 606-8, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12946727

RESUMEN

The antibacterial activity of the methylene chloride and methanol extracts of Chrysantemum coronarium fresh flower heads was investigated. The methylene chloride extract showed discrete antimicrobial activity.


Asunto(s)
Antibacterianos/farmacología , Chrysanthemum , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Fitoterapia , Extractos Vegetales/farmacología , Antibacterianos/administración & dosificación , Antibacterianos/uso terapéutico , Flores , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico
8.
J Nat Prod ; 64(9): 1123-6, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11575941
9.
Fitoterapia ; 72(4): 418-20, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11395268

RESUMEN

The antibacterial activities of the resinous exudates from Haplopappus uncinatus and H. foliosus are reported. The results provide a justification to the traditional use of the resinous exudates of Haplopappus spp as an antiseptic.


Asunto(s)
Antibacterianos/farmacología , Asteraceae , Bacterias Grampositivas/efectos de los fármacos , Plantas Medicinales , Humanos , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología , Estructuras de las Plantas , Resinas de Plantas
11.
J Ethnopharmacol ; 72(3): 459-64, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10996286

RESUMEN

The antimicrobial properties of the resinous exudate from twigs and leaves of a population of Pseudognaphalium vira vira were re-examined against five Gram positive bacteria. The observed decrease in the antimicrobial activity might reflect a change in the diterpenoid composition of the exudate. The title compound 2 was isolated in substantial amount, together with ent-16-kauren-19-oic acid (1), and its structure determined by X-ray diffraction analysis.


Asunto(s)
Antibacterianos/farmacología , Asteraceae/química , Diterpenos/farmacología , Bacterias Grampositivas/efectos de los fármacos , Antibacterianos/química , Diterpenos/química , Diterpenos/aislamiento & purificación , Enlace de Hidrógeno , Estructura Molecular , Difracción de Rayos X
12.
Mag. int. coll. dent ; 7(1): 23-9, jan. 2000. tab, graf
Artículo en Español | LILACS | ID: lil-290353

RESUMEN

This study evaluated the reduction on Mutans Streptococci levels in free caries patients with the use of 10 por ciento chlorhexidine varnish, and chlorhexidine mouthrinses in two different concentrations 0.1 percent and 0.12 percent. After finished the restoratives treatment 48 patients caries free were divided in four groups of 12 patients each one. Group A treatted with 10 percent CHX varnish in one time; Group B mouth rinse with CHX, 12 percent twice a day for 20 days; Group C mouth rinse with CHX 0,1 percent twice a day during 20 days; and group D as control. Group A show the better reduction of s. mutans in saliva by Cariscreen method. The period of the study was two month


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Clorhexidina/uso terapéutico , Streptococcus mutans/efectos de los fármacos , Clorhexidina/efectos adversos , Clorhexidina/farmacología , Caries Dental , Caries Dental/tratamiento farmacológico , Caries Dental/microbiología , Streptococcus mutans/química
13.
Free Radic Res ; 30(6): 471-7, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10400459

RESUMEN

Total reactive antioxidant potential (TRAP) of resinous exudates from Heliotropium species was evaluated by measuring the bleaching of stable free radicals. The antioxidant capacity of the resinous exudates in Trolox equivalents, evaluated from the bleaching of ABTS derived radical cations, ranged from 2.0 M (H. huascoense) to 5.2 M (H. stenophyllum), indicating a very high concentration of phenolic compounds. Considerably smaller values were obtained by measuring the bleaching of DPPH radicals. The ratio between the values obtained employing ABTS derived radicals and DPPH, ranged from 37 (H. megalanthum) to 4.5 (H. chenopodiaceum variety typica). The magnitude of the difference can be considered as an indication of the relative reactivity of the antioxidants present in the exudates. Similar ratios were observed when stoichiometric coefficients were evaluated for representative purified flavonoids obtained from the resinous exudates.


Asunto(s)
Antioxidantes/metabolismo , Bepridil/análogos & derivados , Picratos , Plantas , Resinas de Plantas/metabolismo , Ácidos Sulfónicos/metabolismo , Antioxidantes/análisis , Benzotiazoles , Bepridil/metabolismo , Compuestos de Bifenilo , Cationes/metabolismo , Cromanos/metabolismo , Flavonoides/aislamiento & purificación , Flavonoides/metabolismo , Radicales Libres/metabolismo , Fenoles/metabolismo , Resinas de Plantas/química
14.
J Nat Prod ; 62(2): 381-2, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10075795

RESUMEN

Two new acylated flavonoids have been isolated from the resinous exudates of Pseudognaphalium robustum and Pseudognaphalium cheirantifolium. Their structures were elucidated by high-resolution spectroscopic methods as 5,7,8-trihydroxy-3-methoxyflavone 8-O-[(E)-2-methyl-2-butenoate] (1) and 5,7,8-trihydroxy-3, 6-dimethoxyflavone 8-O-[(E)-2-methyl-2-butenoate] (2).

15.
J Ethnopharmacol ; 62(3): 251-4, 1998 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9849637

RESUMEN

The antimicrobial properties of the resinous exudate from twigs and leaves of Eupatorium salvia were tested against five gram-negative and five gram-positive bacteria. Comparison of the antimicrobial activities of 7-hydroxy-8(17)-labden-15-oic acid (salvic acid) and of its acetate, both compounds isolated from the plant, with that of the crude extract suggested that the latter ester derivative was the major active component in the exudate. These results validate the vernacular medicinal use of Eupatorium salvia as an antiseptic agent.


Asunto(s)
Antibacterianos/farmacología , Asteraceae/química , Diterpenos/farmacología , Extractos Vegetales/farmacología , Ampicilina/farmacología , Cloranfenicol/farmacología , Recuento de Colonia Microbiana , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Técnicas In Vitro , Tetraciclina/farmacología
16.
J Ethnopharmacol ; 58(2): 85-8, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9406895

RESUMEN

The antimicrobial properties of the resinous exudates from twigs and leaves of four Chilean species of Pseudognaphalium: P. viravira, P. robustum, P. heterotrichium and P. cheiranthifolium were tested against six gram negative bacteria and five gram positive bacteria. The extracts share similar antimicrobial activities against the gram positive bacteria. The antimicrobial activity correlated very well with the presence in the resinous exudates of ent-16-kauren-19-oic acid and to a lesser extent with the presence of ent-9(11),16-kauradien-19-oic. Introduction of an hydrophilic 3 beta-OH drastically reduced the antimicrobial activity of these compound. The activity was not correlated with the flavonoid content of those resinous exudates.


Asunto(s)
Diterpenos/farmacología , Flavonoides/farmacología , Extractos Vegetales/farmacología , Bacterias/efectos de los fármacos , Chile , Diterpenos/aislamiento & purificación , Flavonoides/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Resinas de Plantas/aislamiento & purificación , Resinas de Plantas/farmacología
17.
Rev. dent. Chile ; 88(1): 28-35, abr. 1997. ilus, tab
Artículo en Español | LILACS | ID: lil-200177

RESUMEN

Se realizó una investigación con el fin de evaluar la variación en los niveles salivales de Estreptococo mutans en pacientes que debían colocarse aparatos de orthodoncia fijos, y la posible relación entre estos niveles y el material utilizado para la cementación de dichos aparatos. Para ello se utilizó una muestra de dieciséis pacientes. A seis de ellos se les cementó los brackets con un cemento de vidrio ionómero híbrido de fotocurado. A cinco pacientes se les cementó los brackets con una resina compuesta fluorada. Como grupo control, se utilizó una muestra de cinco pacientes a los cuales se les cementó los brackets con una resina compuesta convencional. En todos los pacientes se utilizó un cemento de vidrio ionómero convencional para el cementado de las bandas ubicadas en los cuatro primeros molares. A todos los pacientes se les efectuó un test Carescreen antes y 3 meses después de la colocación de los aparatos. Se obtuvo como resultado un incremento en los niveles salivales de Estreptococo mutans en los tres grupos. Se utilizó el test del Signo de Wilcoxon para analizar la variación obtenida en cada grupo por separado. Tanto para el grupo control como para el grupo que utilizó un composite fluorado, el incremento observado alcanzó un valor cercano a la significación estadística (p=0.063, no significativo, para cada grupo), en tanto que la variación observada para el grupo que utilizó un cemento de vidrio ionómero, el valor obtenido fue de p=0.625, no significativo. El test Kruskal-Wallis no mostró diferencias significativas entre los grupos analizados (p=0.142)


Asunto(s)
Humanos , Masculino , Femenino , Cementos de Ionómero Vítreo/química , Resinas Compuestas/química , Saliva/microbiología , Streptococcus mutans/aislamiento & purificación , Cementación/instrumentación , Clorhexidina/uso terapéutico , Recuento de Colonia Microbiana , Fluoruros/uso terapéutico , Soportes Ortodóncicos , Interpretación Estadística de Datos
18.
J Ethnopharmacol ; 45(1): 71-4, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7739230

RESUMEN

The antimicrobiol properties and preliminary chemical information of the resinous exudates from twigs and leaves of nine Haplopappus species from Chile: H. diplopappus; H. anthylloides; H. schumannii; H. cuneifolius; H. velutinus; H. uncinatus; H. multifolius, H. illinitus and H. foliosus are presented. The results show that those species of genus Haplopappus share similar antimicrobial activities although they differ dramatically in the chemical composition.


Asunto(s)
Antiinfecciosos/farmacología , Plantas Medicinales/química , Resinas de Plantas/farmacología , Antibacterianos , Bacterias/efectos de los fármacos , Chile , Hongos/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Hojas de la Planta/química , Tallos de la Planta/química
20.
Rev. dent. Chile ; 85(2): 87-90, ago. 1994. tab
Artículo en Español | LILACS | ID: lil-144089

RESUMEN

The aim of the present clinical investigation was to evaluate the effect of tranexamic acid in the treatment of discrasies patients. In the study we observed that antifibrinolytic therapy with tranexamic acid used with ystemic therapy significantly reduces the incidence of postoperative bleeding


Asunto(s)
Humanos , Niño , Adolescente , Adulto , Ácido Tranexámico/uso terapéutico , Paraproteinemias/tratamiento farmacológico , Ácido Tranexámico/administración & dosificación , Ácido Tranexámico/farmacocinética , Fibrinólisis/fisiología , Terapia Trombolítica/métodos , Resultado del Tratamiento
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