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1.
Mar Pollut Bull ; 161(Pt A): 111750, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33132148

RESUMEN

This study focused on investigating the occurrence, quantification, and the spatial and temporal distribution of plastics in coastal surface water from 12 coastal regions in southern part of Sri Lanka. The overall average densities of macroplastics and mesoplastics were recorded as 0.23 and 0.33 items/m3, respectively. Sampling locations had no significant difference (p > 0.05) on total microplastics (MPs) density (overall mean MPs density: 17.45 ± 3.35 items/m3). MPs debris of less than 1 mm size consisted of >45% of the total number of MPs, whereas the maximum size of microscopically observed plastic debris was 11.04 mm, a filament. Filaments were the most common MPs followed by films. Relatively, blue-colored MPs were highly abundant in this coastal line. The type of MPs was further confirmed by Fourier-Transform Infrared (FTIR) method. Potential plastic pollution factors are hydrodynamics and man-made activities like unsustainable harbor operations, fisheries, and tourism. More attention is needed to reduce plastic pollution regionally.


Asunto(s)
Plásticos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Humanos , Océano Índico , Espectroscopía Infrarroja por Transformada de Fourier , Sri Lanka , Agua , Contaminantes Químicos del Agua/análisis
2.
J Ethnopharmacol ; 69(1): 57-62, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10661884

RESUMEN

Rosmarinus officinalis L. crude hydroalcoholic (70%) extract was evaluated for antiulcerogenic activity employing different experimental models. The crude hydroalcoholic extract (CHE) decreased the ulcerative lesion index produced by indomethacin, ethanol and reserpine in rats. No antisecretory activity was observed on pyloric ligation model. The previous administration of L-NAME, a NO-synthase inhibitor, did not reduce the antiulcerogenic activity of CHE in ethanol induced ulcer model, suggesting that the pharmacological mechanism has no relationship with nitric oxide (NO). Whereas when the animal groups were treated with indomethacin, using the same experimental model, CHE did not reduce the antiulcerogenic activity, suggesting that the pharmacological mechanism has no relationship with prostaglandins. The previous treatment with N-ethymaleimide, a thiol blocker, including mucosal nonprotein sulfhydryl groups, reduced the anitulcerogenic activity of CHE on ethanol induced ulcer model. This result suggests that the crude hydroalcoholic extract of R. officinalis L. has active substances that increase the mucosal nonprotein sulfhydryl groups content. In another hypothesis, the pharmacological mechanism could be attributed to the activity of antioxidant compounds found in the crude hydroalcoholic extract which can react with N-ethylmaleimide.


Asunto(s)
Antiulcerosos/farmacología , Ácido Gástrico/metabolismo , Fitoterapia , Extractos Vegetales/farmacología , Plantas Medicinales/uso terapéutico , Animales , Interacciones Farmacológicas , Inhibidores Enzimáticos/farmacología , Etanol , Etilmaleimida/farmacología , Indometacina , Ligadura , Masculino , NG-Nitroarginina Metil Éster/farmacología , Extractos Vegetales/aislamiento & purificación , Píloro/cirugía , Ratas , Ratas Wistar , Reserpina , Solubilidad , Compuestos de Sulfhidrilo/antagonistas & inhibidores , Factores de Tiempo
3.
J Ethnopharmacol ; 72(3): 465-8, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10996287

RESUMEN

An easy methodology for triterpene isolation is shown. Evaluation in rats for antiulcer activity of friedelan-3beta-ol 1 and friedelin 2. The two triterpenes isolated from the leaves of Maytenus ilicifolia, did not decrease gastric ulcers when tested on indometacine induced ulcer model in rats.


Asunto(s)
Antiulcerosos/farmacología , Rosales/química , Triterpenos/farmacología , Animales , Antiulcerosos/química , Antiulcerosos/aislamiento & purificación , Evaluación de Medicamentos , Cromatografía de Gases y Espectrometría de Masas , Indometacina/efectos adversos , Espectroscopía de Resonancia Magnética , Masculino , Ratas , Ratas Wistar , Úlcera Gástrica/inducido químicamente , Úlcera Gástrica/prevención & control , Triterpenos/química , Triterpenos/aislamiento & purificación
4.
Neotrop Entomol ; 40(1): 112-6, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21437492

RESUMEN

The lady beetle Coleomegilla maculata (De Geer) is a natural enemy of several insect pests and feeds on pollen and nectar to survive periods when prey is scarce. The effect of the feeding interval on the development, survival, fecundity, and longevity of C. maculata was determined. Newly hatched larvae of C. maculata were reared individually and fed with eggs of the Mediterranean flour moth Anagasta kuehniella (Zeller) at intervals of one, two, and three days under controlled conditions (23 ± 1ºC; 60 ± 10% RH; 12 h phtophase). The duration of larval instars and the total larval stage was prolonged as the feeding interval increased. The larval period lasted on average 9.2 ± 0.19 days when the larvae were fed daily with prey, and 14.6 ± 0.48 days when food was offered at three-day intervals. There was an inverse relationship between food intervals, survival, and weight of larvae and adults of the coccinellid. Survival rate of larvae fed daily was 76.8%, while the rate was 50.0% and 23.4% for larvae fed every two and three days, respectively. Coleomegilla maculata showed fecundity of 781.1 ± 149.02, 563.4 ± 80.81 and 109.0 ± 103.0 eggs when fed daily and at intervals of two and three days, respectively.


Asunto(s)
Escarabajos/crecimiento & desarrollo , Privación de Alimentos , Animales , Factores de Tiempo
5.
Trends Ecol Evol ; 11(8): 326-30, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21237863

RESUMEN

The various habitats inhabited by a given species are never of the same quality. When demographic models take into account this habitat heterogeneity, the source-sink concept naturally emerges: a local demographic surplus arises in good quality habitats (source), and a local demographic deficit occurs in habitats of poor quality (sink). Within a landscape, a permanent migration of propagules or individuals from source to sink habitats may lead to a stabilization of the overall demographic system. This simple situation, explored in the recent literature, has surprising properties. In particular, it requires a change in our view of classical concepts such as ecological niche and carrying capacity, it can explain the existence and persistence of local maladaptation and it can improve conservation practice.

6.
Rev Panam Salud Publica ; 10(2): 79-85, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11575243

RESUMEN

OBJECTIVE: To assess the validity of recommendations for use of the 85th and 95th percentiles of body mass index (BMI) of the population in the United States of America as a screening tool to assess overweight/obesity in adolescents. METHODS: We investigated the relation between BMI and percent body fat in 1,540 adolescents (717 males and 823 females) aged 10 to 17.9 years old from a private high school in Niterói, a city in the state of Rio de Janeiro, Brazil. We used bioelectric impedance, with the appropriate equations for adolescents, to estimate percent body fat, which served as the gold standard (30% for girls and 25% for boys) to calculate the sensitivity and specificity of the 85th and 95th percentiles of the United States and Brazilian distribution curves of BMI. RESULTS: Sensitivity and specificity were high (above 80%) for the Niterói boys, except for the 85th percentile of the Brazilian curve (specificity = 61.8%) and for the 95th percentile of the United States curve (sensitivity = 55.4%). For the Niterói girls, the 85th- and 95th-percentile BMI cutoff points, from both the United States and Brazilian curves, showed low sensitivity, and that sensitivity decreased with age. Specificity was high for the girls, and much higher than it was for the boys. CONCLUSIONS: These data suggest that using BMI to screen for overweight/obesity in adolescents can generate a high percentage of false-positives for Niterói boys and an even higher percentage of false-negatives for Niterói girls. A more universal approach to using anthropometric measures to screen for overweight/obesity should be developed, preferably linked to stages of maturation.


Asunto(s)
Índice de Masa Corporal , Obesidad/epidemiología , Adolescente , Peso Corporal , Brasil , Niño , Femenino , Humanos , Masculino , Sensibilidad y Especificidad , Estados Unidos
7.
Phytother Res ; 15(8): 670-5, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11746858

RESUMEN

The resulting enriched sesquiterpene lactone fraction and the crude ethanol extract of Artemisia annua L. aerial parts, showed antiulcerogenic activity when administered orally, on the indomethacin induced ulcer in rats. The sesquiterpene lactone fraction yielded three different polarity fractions on column chromatography as follows: non-polar, medium polarity and polar fraction, When submitted to the same indomethacin-induced ulcer in rats they resulted in different levels of inhibition of the ulcerative lesion index. The participation of nitric oxide was evaluated on an ethanol-induced ulcer model which had a previous administration of L-NAME, a NO-synthase inhibitor. Under these conditions, the medium polarity fraction maintained the antiulcerogenic activity, suggesting that nitric oxide could not be involved in the antiulcerogenic activity. When the animal groups were treated with N-ethylmaleimide, an alkylator of sulphhydryl groups, using the same experimental model, the medium polarity fraction maintained its antiulcerogenic activity, suggesting that the pharmacological mechanism is not related to non-protein sulphydryl compounds. On the ethanol-induced ulcer with previous indomethacin treatment, the medium polarity fraction lost its antiulcerogenic activity indicating that the active compounds of Artemisia annua L. increase the prostaglandin levels in the gastric mucosa. This hypothesis was reinforced by an increase of adherent mucus production by the gastric mucosa, produced by the medium polarity fraction on the hypothermic restraint stress induced ulcer model.


Asunto(s)
Antiulcerosos/uso terapéutico , Artemisia , Fitoterapia , Extractos Vegetales/uso terapéutico , Úlcera Gástrica/tratamiento farmacológico , Animales , Etanol , Etilmaleimida , Cromatografía de Gases y Espectrometría de Masas , Mucosa Gástrica/efectos de los fármacos , Hipotermia Inducida , Indometacina , Masculino , NG-Nitroarginina Metil Éster , Extractos Vegetales/farmacología , Tallos de la Planta , Ratas , Ratas Wistar , Úlcera Gástrica/inducido químicamente , Estrés Fisiológico
8.
Trends Ecol Evol ; 12(4): 161, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21238017
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