RESUMEN
Plasma treatment is recognized as a suitable technology to improve germination efficiency of numerous seeds. In this work Quinoa seeds have been subjected to air plasma treatments both at atmospheric and low pressure and improvements found in germination rate and percentage of success. Seed water uptake by exposure to water vapor, although slightly greater for plasma treated seeds, did not justify the observed germination improvement. To identify other possible factors contributing to germination, the chemical changes experienced by outer parts of the seed upon plasma exposure have been investigated by X-ray photoemission spectroscopy (XPS) and scanning electron microscopy (SEM-EDX). XPS revealed that the outer layers of the Quinoa plasma treated seeds were highly oxidized and appeared enriched in potassium ions and adsorbed nitrate species. Simultaneously, SEM-EDX showed that the enrichment in potassium and other mineral elements extended to the seed pericarp and closer zones. The disappearance from the surface of both potassium ions and nitrate species upon exposure of the plasma treated seeds to water vapor is proposed as a factor favoring germination. The use of XPS to study chemical changes at seed surfaces induced by plasma treatments is deemed very important to unravel the mechanisms contributing to germination improvement.
Asunto(s)
Chenopodium quinoa/química , Germinación/efectos de los fármacos , Gases em Plasma/farmacología , Semillas/química , Espectroscopía de Fotoelectrones , Semillas/ultraestructura , Propiedades de Superficie , Agua/químicaRESUMEN
PURPOSE: To investigate in vivo the survival of abducens motoneurons (AMNs) at different periods of time after a single intramuscular injection of the neurotoxin botulinum toxin A (BTxA) or doxorubicin (DXR). METHODS: In Sprague-Dawley rats, the AMNs were labeled with fluorogold (FG), which was applied intramuscularly in the lateral rectus muscle. The numbers of labeled neurons were determined in adult control animals; in young animals that had received intramuscular injections of 0.125, 0.250, 1, or 2 U BTxA; and in adult rats that had received 100 microg, 200 microg, or 300 microg DXR, at various survival times. RESULTS: In control animals, the numbers of FG-labeled motoneurons were similar to the numbers found by other investigators with the use of other retrogradely transported tracers; motoneuron numbers diminished with time after FG application. The numbers of FG-labeled neurons in the animals that had been injected with BTxA were similar to those found in control animals. However, there were fewer FG-labeled neurons in the animals injected with DXR. CONCLUSIONS: Fluorogold injected into the lateral rectus muscle can be used to label the AMNs. However, this tracer does not persist within the cytoplasm of the labeled neurons for more than 37 days. The intramuscular injection of 0.125, 0.250, 1, or 2 U BTxA does not induce significant motoneuron death in young rats 30, 60, or 90 days after the injection. Doxorubicin injected intramuscularly causes variable amounts of motoneuron death that is related both to the survival period and to the amount of DXR injected.
Asunto(s)
Nervio Abducens/efectos de los fármacos , Toxinas Botulínicas Tipo A/farmacología , Doxorrubicina/farmacología , Neuronas Motoras/efectos de los fármacos , Fármacos Neuromusculares/farmacología , Músculos Oculomotores/efectos de los fármacos , Nervio Abducens/citología , Animales , Recuento de Células , Supervivencia Celular/efectos de los fármacos , Femenino , Inyecciones Intramusculares , Masculino , Neuronas Motoras/citología , Ratas , Ratas Sprague-DawleyRESUMEN
Esthesioneuroblastoma is a rare tumor that originates in the olfactory epithelium and can invade the orbit. We report a case in which the first symptom was a post-traumatic paralysis of the IV cranial nerve. Whether the tumor itself or the trauma or a combination of the two factors caused the paralysis is discussed.