ABSTRACT
The bioactivity of caffeine aqueous solutions (0.20-2.00 wt %) and caffeine oleate emulsions (20 vol % oil, 2.00 wt % surfactant, 0.04 wt % caffeine, 0.05 wt % oleic acid) was assessed against two biological models: Drosophila melanogaster and Hypothenemus hampei. The caffeine aqueous solutions showed no insecticidal activity, whereas caffeine oleate emulsions had high bioactivity against both D. melanogaster and H. hampei. By preparing the caffeine oleate emulsions with anionic surfactants (i.e., sodium lauryl sulfate, sodium laureate, and sodium oleate), we obtained a lethal time 50 (LT50) of 23 min. In the case of caffeine oleate emulsions prepared with nonionic surfactants (i.e., Tween 20 and Tween 80), a LT50 of approximately 17 min was observed. The high bioactivity of the caffeine oleate emulsion against H. hampei opens the possibility of using this insecticide formulation as an effective way to control this pest that greatly affects coffee plantations around the world.
Subject(s)
Caffeine/administration & dosage , Coleoptera , Drosophila melanogaster , Insecticides/administration & dosage , Oleic Acids/administration & dosage , Animals , Emulsions , Solutions , WaterABSTRACT
The natural habitat of Paracoccidioides brasiliensis remains undefined but the repeated demonstration of infection by this fungus in the nine-banded armadillo Dasypus novemcinctus has opened interesting research avenues. We report here the isolation of this fungus from the spleen of a naked-tailed armadillo Cabassous centralis (Miller 1899) captured in a coffee farm localized in the Colombian endemic area for paracoccidioidomycosis. This particular isolate was identified by its dimorphism and also by comparison of the PbGP43 gene and ribosomal internal transcribed spacer regions (ITS) with recognized P brasiliensis strains. This finding extends the range of naturally acquired infections in mammals of the family Dasypodidae and confirms the existence of this human pathogen in areas where human paracoccidioidomycosis is known to occur.
Subject(s)
Armadillos/microbiology , Paracoccidioides/isolation & purification , Animals , Colombia , DNA, Ribosomal Spacer/genetics , Genes, Fungal/genetics , Molecular Sequence Data , Paracoccidioides/genetics , Species Specificity , Spleen/microbiologyABSTRACT
Young red tilapias were exposed for 96 h to each one of 6 concentrations of the pesticide Diazinon in order to determine the pesticide's acute toxicity level. After the ascertaining the lethal concentration (LC50) at 96 h, a level 10 times lower was selected for the bioaccumulation study of the pesticide in male and female specimens exposed for 9 days. The elimination process was carried out for 10 days beginning right after the conclusion of the accumulation process. Analytical procedures were developed and used for the studies of acute toxicity and bioaccumulation of Diazinon in red tilapia. A lethal concentration [LC50 (96 h)] of 3.85 mg/L was found, and steady-state accumulation, at a concentration of 28.45 mg/kg, was reached at 7.72 days. In the elimination process a concentration of 0.29 mg/kg was found in tilapia tissue by the sixth day after the fish were moved to clean water, and it continued to decrease quickly toward nondetectable levels.
Subject(s)
Diazinon/pharmacokinetics , Diazinon/toxicity , Insecticides/pharmacokinetics , Insecticides/toxicity , Tilapia/physiology , Water Pollutants, Chemical/pharmacokinetics , Water Pollutants, Chemical/toxicity , Animals , Half-Life , Lethal Dose 50 , Tissue DistributionABSTRACT
Objetivos: Determinar la eficacia del uso del microdebridador en pacientes con hipertrofia de cornetes, así como los cambios histopatologicos que se presentan en la mucosa, antes y después de su utilización. Establecer el pronostico a largo plazo. Materiales y Métodos: Estudio prospectivo de 11 pacientes (22 procedimientos) con obstrucción crónica nasal secundaria a hipertrofia de los cornetes inferiores, refractarios al tratamiento médico, a quienes se les realizó resección submucosa con el microdebridador, tomando biopsia prequirurgica y postquirurgica para la evaluación de los cambios histopatologicos al mes y al año del procedimiento. Resultados: Se demuestra una correlación clínica con cambios regenerativos en la mucosa del cornete inferior al año del procedimiento quirúrgico.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Nasal Mucosa , Nasal Obstruction/surgery , Turbinates , Hypertrophy , Surgical Instruments/trendsSubject(s)
Humans , Male , Female , Radiation Protection , Radiation Protection/standards , Radiology Department, Hospital , ColombiaABSTRACT
Con el fin de conocer su morbilidad respiratoria se estudiaron los 36 trabajadores de la Empres de Talcos de Yarumal (Antioquia-Colombia); a cada trabajador se le realizaron historia clinica y ocupacional; examen fisico; estudios radiologicos de torax; espirometria; pruebas de tuberculina e histoplasmina; baciloscopias y cultivos para micobacterias. Se hicieron igualmente mediciones del grado de contaminacion del ambiente laboral. Se encontro una alta frecuencia de sintomatologia respiratoria previa; la mitad de los trabajadores anomalias al examen fisico; dos terceras partes tenian anormalidades radiologicoas y una tercera parte anormalidades espirometricas
