Synergy of the Tropical Earthworm Pontoscolex corethrurus and Oil Palm Bagasse in the Removal of Heavy Crude Oil.

The tropical endogeic earthworm Pontoscolex corethrurus, a non-standard species used in ecotoxicity, has been found in crude oil-contaminated habitats. We estimated the removal of total hydrocarbons from heavy crude "Maya" oil on an artificially contaminated soil with a median lethal concentration of P. corethrurus and an addition of oil palm bagasse. P. corethrurus had a high survival rate, and the addition of oil palm bagasse led to a greater growth and an increase in abundance of bacteria and fungi. The activity of P. corethrurus and the nutritional quality of oil palm bagasse had a significant impact on the removal of a larger amount of petroleum hydrocarbons from contaminated soil. We concluded that the endogeic earthworm P. corethrurus and oil palm bagasse acted synergistically to achieve a more effective removal of total petroleum hydrocarbons from soil. These results show the potential for using P. corethrurus to remove, either directly or indirectly, crude oil from soil.

Genetically-engineered plants yield an orally immunogenic PirA-like toxin from Vibrio parahaemolyticus.

Vibrio parahaemolyticus is the main etiological agent of human gastroenteritis by seafood consumption and some strains from this species causing the Acute Hepatopancreatic Necrosis Disease in shrimp have been recently reported. The PirA-like toxin from V. parahaemolyticus (ToxA) has been recently reported as an attractive antigen implicated in subunit vaccine development. Since plants are attractive hosts for the production and delivery of vaccines in the present study plants expressing ToxA were developed to account with a low cost platform for the production and oral delivery of ToxA. Tobacco plants were genetically engineered by Agrobacterium-mediated transformation to stably integrate the ToxA-coding gene into the nuclear genome. Transgenic lines were rescued in kanamycin-containing medium and analyzed by ELISA to determine ToxA yields observing levels up to 9 µg g-1 FW leaf tissues. Western blot analysis confirmed the presence of the ToxA protein in plant extracts. Immunogenicity assessment of the plant-made ToxA was performed in mice, comprising a 4-dose oral immunization scheme; revealing the induction of anti-ToxA humoral responses (IgG in serum and IgA in feces). This study opens the path for the development of low cost plant-based vaccines against Vibrio parahaemolyticus.

Sensitivity of the Endogeic Tropical Earthworm Pontoscolex corethrurus to the Presence of Heavy Crude Oil.

Contamination of soil with petroleum is common in oil-producing areas across the tropical regions of the world. There is limited knowledge on the sensitivity of endogeic tropical earthworms to the contamination of soil with total petroleum hydrocarbons (TPH) present in crude oil. Pontoscolex corethrurus is a dominant species in tropical agroecosystems around oil-processing facilities. The sensitivity of P. corethrurus to soil artificially contaminated with "Maya" Mexican heavy crude oil was investigated through avoidance and acute ecotoxicity tests, using the following measured concentrations: 0 (reference soil), 551, 969, 4845, 9991 and 14,869 mg/kg. The avoidance test showed that P. corethrurus displayed a significant avoidance behavior to heavy crude oil at a concentration of 9991 mg/kg or higher. In contrast, acute toxicity tests indicate that the median lethal concentration (LC50) was 3067.32 mg/kg; however, growth (weight loss) was more sensitive than mortality. Our study revealed that P. corethrurus is sensitive to TPH, thus highlighting the importance of P. corethrurus for petroleum ecotoxicological tests.

Artificial feeding synchronizes behavioral, hormonal, metabolic and neural parameters in mother-deprived neonatal rabbit pups.

Nursing in the rabbit is under circadian control, and pups have a daily anticipatory behavioral arousal synchronized to this unique event, but it is not known which signal is the main entraining cue. In the present study, we hypothesized that food is the main entraining signal. Using mother-deprived pups, we tested the effects of artificial feeding on the synchronization of locomotor behavior, plasma glucose, corticosterone, c-Fos (FOS) and PERIOD1 (PER1) rhythms in suprachiasmatic, supraoptic, paraventricular and tuberomammillary nuclei. At postnatal day 1, an intragastric tube was placed by gastrostomy. The next day and for the rest of the experiment, pups were fed with a milk formula through the cannula at either 02:00 h or 10:00 h [feeding time = zeitgeber time (ZT)0]. At postnatal days 5-7, pups exhibited behavioral arousal, with a significant increase in locomotor behavior 60 min before feeding. Glucose levels increased after feeding, peaking at ZT4-ZT12 and then declining. Corticosterone levels were highest around the time of feeding, and then decreased to trough concentrations at ZT12-ZT16, increasing again in anticipation of the next feeding bout. In the brain, the suprachiasmatic nucleus had a rhythm of FOS and PER1 that was not significantly affected by the feeding schedule. Conversely, the supraoptic, paraventricular and tuberomammillary nuclei had rhythms of both FOS and PER1 induced by the time of scheduled feeding. We conclude that the nursing rabbit pup is a natural model of food entrainment, as food, in this case milk formula, is a strong synchronizing signal for behavioral, hormonal, metabolic and neural parameters.

Análisis descriptivo de asistencia dermatológica a mayores de 65 años durante un período de seis meses en el Servicio de Urgencia Externa / Descriptive analysis of dermatological care in the elderly patients over 65 years during a six month period in the Outpatient Emergency Service

OBJETIVO: Estudiar las patologías dermatológicas en personas mayores de 65 años que han motivado consulta al Servicio de Urgencia Externa del Hospital de Referencia de Granada Sur durante un período de seis meses. Determinar la necesidad de la figura del Dermatólogo de guardia. MATERIAL Y MÉTODOS: Se aplicó un protocolo de estudio a las personas mayores de 65 años atendidas por el dermatólogo de guardia del hospital. RESULTADOS: Los pacientes ancianos suponen el 17 por ciento de los pacientes atendidos en las urgencias, un porcentaje nada desdeñable que no se aleja de las diferencias observadas en las pirámides de edad actuales. Existe un discreto predominio femenino (55,5 por ciento), con una media de edad de 74,3 años, que consultan por dermatosis agudas en su mayoría y que proceden de Granada capital y su cinturón metropolitano (61 por ciento). El 62,19 por ciento de los pacientes consultan cuando el tiempo de evolución de la lesión que presentan es inferior al mes. La mayoría de estos casos (57 por ciento) son revisados por el Servicio de Dermatología, posteriormente con un porcentaje de ingresos que sólo alcanza el 1 por ciento. CONCLUSIONES: Nuestros resultados pretenden dar a conocer las patologías de más frecuente presentación en nuestra población de referencia y se plantea la discusión sobre la necesidad de la figura del dermatólogo de guardia o el 'dermatólogo de cabecera' en virtud a la configuración actual de nuestros servicios sanitarios (AU)

Anti-inflammatory properties of mizolastine after oral administration on arachidonic acid-induced cutaneous reaction in the rat.

The anti-inflammatory effect of mizolastine (CAS 108612-45-9, SL85.0324-00), a new non-sedative histamine H1-receptor antagonist, was assessed in comparison to loratadine, terfenadine and pyrilamine. Intraplantar injection of arachidonic acid (AA) into the rat paw was followed by a rapid and sustained (> or = 4h) inflammatory oedema. Mizolastine (0.1 to 10 mg/ kg p.o.) inhibited in a dose-dependent manner the time course of the AA-induced paw inflammation as from the dose of 0.1 mg/kg p.o. This effect was maintained for at least the 4 h of observation (-44% at 0.3 mg/kg p.o.) suggesting a long lasting action of mizolastine. Although with higher maximal effect, a similar time course of response was observed with dexamethasone at 0.1 mg/kg p.o. In contrast, at anti-histamine, doses, the histamine H1-receptor antagonists terfenadine (1 to 30 mg/kg p.o.), loratadine (10 mg/kg p.o.), and pyrilamine (10 mg/kg p.o.) failed to inhibit significantly the inflammatory action of AA. Moreover, under conditions of H1-receptors blockade (e.g. when co-administered with pyrilamine or loratadine (10 mg/kg p.o.), the inhibition by mizolastine (0.3 mg/kg) of AA-induced inflammation was unchanged. This suggests that the anti-inflammatory effect of mizolastine was unrelated to its histamine H1-receptor antagonist properties. It is proposed that a primary effect on the lipoxygenase pathway may contribute to this action of mizolastine. This is based on the observations that mizolastine inhibits 5-lipoxygenase activity in vitro. Furthermore, a high dose of mizolastine (50 mg/kg) did not affect the inflammatory response to carrageenin which is mediated by the cyclooxygenase pathway. Together, these data indicate that mizolastine is orally effective in this animal model for cutaneous inflammation. Combined with its blockade of histamine H1-receptors, this property may contribute to its possible use in allergic inflammation or other inflammatory states.

Regulation of the anorectic drug recognition site during glucoprivic feeding.

The acute effects of 2-deoxy-D-glucose (2-DG)-induced glucoprivic feeding on the anorectic drug recognition site and Na+K(+)-ATPase in the brain were examined in adult rats and in lean and genetically obese mice. The marked hyperglycemia and the induction of feeding caused by the administration of 2-DG to satiated rats and lean mice were associated with significant increases in Na+K(+)-ATPase activity, and in [3H]ouabain binding and [3H]mazindol binding to the anorectic drug recognition site in hypothalamic membranes. Basal and 2-DG-stimulated levels of blood glucose were significantly correlated to the levels of hypothalamic [3H]ouabain (r = + .91, p less than 0.01) and [3H]mazindol (r = + .87, p less than 0.01) binding. A significant correlation (r = .74, p less than 0.05) was also observed between [3H]mazindol binding and [3H]ouabain binding supporting the hypothesis that these hypothalamic binding sites are functionally coupled in their response to circulating glucose. Following the intracerebroventricular (ICV) administration of the diabetogenic drug alloxan, 2-DG did not stimulate feeding or increase [3H]mazindol and [3H]ouabain binding sites in the hypothalamic paraventricular area. Since 2-DG still caused hyperglycemia in alloxan-treated rats, alloxan-induced inactivation of glucoreceptor mechanisms led to an uncoupling of the anorectic drug recognition site from a hypothalamic glucostat. In genetically obese mice (ob/ob), 2-DG also could not induce feeding or increase hypothalamic [3H]ouabain or [3H]mazindol binding, despite a significant hyperglycemic response. In contrast, 2-DG did increase feeding and the binding of [3H]ouabain and [3H]mazindol to the hypothalamus of lean littermates.(ABSTRACT TRUNCATED AT 250 WORDS)

Impairment of glucostatic, adrenergic and serotoninergic feeding parallels the lack of glucoprivic signals in the golden hamster.

The administration of 2-deoxyglucose (2-DG) to several animal species, including humans, results in reduction of cellular glucose availability which evokes sympathoadrenal activation, hyperglycemia and stimulation of food intake. We have investigated the effects in the hamster of several drugs which are known to stimulate food intake and induce hyperglycemic response in other species. Golden hamsters pretreated with either 2-DG (0.5 g/kg IP), the alpha-2 adrenoceptor agonist UK-14304 (0.3 mg/kg IP) or the 5-HT1A selective agonist 8-OH-DPAT (0.03 mg/kg IP), have a significant hyperglycemic response, which is similar to the response in mice or rats. However, neither 2-DG, UK-14304 nor 8-OH-DPAT were capable of stimulating food intake in these hamsters. Previous studies in rats and mice demonstrated that hyperglycemic conditions result in activation of a hypothalamic anorectic recognition site, labeled with [3H]mazindol, as well as alpha-2 adrenoceptors, labeled with [3H]idazoxan. No such activation of [3H]mazindol nor [3H]idazoxan binding was observed in the hypothalamus of hamsters treated with 2-DG, despite a normal glycemic response. Thus, in this species an uncoupling between feeding responses and glucoprivic signals may represent a lack of ischymetric regulation of feeding.

Pre- and postsynaptic alpha-2 adrenoceptors as target for drug discovery.

The presynaptic terminal autoreceptors which modulate the release of noradrenaline through a negative feed-back mechanism correspond to the alpha 2-subtype of adrenoceptors. These receptors are also present post-synaptically in the pancreatic islets were they mediate inhibition of the glucose-induced release of insulin. The sympathetic innervation of the pancreatic islets involves alpha 2-adrenoceptors both presynaptically as well as postsynaptically. SL 84.0418 is a novel alpha 2-adrenoceptor antagonist with preferential effects in the periphery and with at least a 10-fold higher selectivity ratio between alpha 2 and alpha 1-adrenoceptors when compared with idazoxan. SL 84.0418 antagonizes the hyperglycemia and the inhibition of insulin release induced by the alpha 2-adrenoceptor agonist UK 14304. The administration of SL 84.0418 significantly reduces the glucose evoked hyperglycemia in several species including man. It is proposed that SL 84.0418 may represent a useful and novel hypoglycemic drug in the treatment of type II diabetes.

The effects of serotonergic and dopaminergic lesions on sodium-sensitive [3H]mazindol binding in rat hypothalamus and corpus striatum.

The effects of intracerebroventricular administration of 6-hydroxydopamine (6-OHDA) and 5,7-dihydroxytryptamine (5,7-DHT) on sodium-sensitive [3H]mazindol binding were investigated in the rat hypothalamus and corpus striatum. In the hypothalamus, specific [3H]mazindol binding was inhibited by low concentrations of sodium and stimulated by high-sodium concentrations, whereas in the corpus striatum, only a sodium-dependent stimulation of [3H]mazindol binding was observed. Lesions with 6-OHDA significantly reduced sodium-dependent [3H]mazindol binding in the corpus striatum, but had no effect on the binding of [3H]mazindol in the absence of sodium. Lesions of serotonergic neurons with 5,7-DHT, however, had no effect on [3H]mazindol binding in the striatum, but resulted in a significant increase in the number of [3H]mazindol binding sites in the hypothalamus. These data suggest that [3H]mazindol may bind to two anatomically distinct binding sites, one that is stimulated and the other inhibited by sodium. The sodium-stimulated binding sites appear to be located on dopaminergic terminals in the striatum, and in the hypothalamus, the sodium-inhibited sites appear to be regulated by serotonergic neuronal activity.

Coupling between hypothalamic alpha 2-adrenoceptors and [3H]mazindol binding site in response to several hyperglycaemic stimuli in mice.

The hypothalamic response to circulating glucose and insulin levels was studied in the mouse by differentially attenuating glucose-homeostasis. The administration of glucose, 2-deoxyglucose or the alpha 2-adrenoceptor agonist UK 14.304 was accompanied by a persistent hyperglycaemia; however, an increase in insulin levels was obtained with glucose and a decrease with the other two manipulations. Both alpha 2-adrenoceptors (labeled with [3H]idazoxan) and the anorectic recognition site (labeled with [3H]mazindol) were upregulated by the three treatments. A good correlation was obtained between circulating glucose levels and either hypothalamic [3H]mazindol binding (r = 0.70, P less than 0.001) or [3H]idazoxan binding (r = 0.63, P less than 0.001), as well as between the two binding sites (r = 0.88, P less than 0.001). No correlation was obtained between circulating insulin levels and these binding sites (r = 0.18, r = 0.26, P = n.s. for [3H]mazindol and [3H]idazoxan binding, respectively). It is suggested the alpha 2-adrenoceptors and the anorectic binding sites are associated in their response to glucose as part of a hypothalamic center involved in the regulation of feeding mechanisms.

Site of action of anorectic drugs: glucoprivic- versus food deprivation-induced feeding.

Feeding induced by 2-deoxyglucose was compared with feeding induced by food deprivation in terms of antagonism by anorectic drugs and of anatomical site of action. Glucoprivic feeding was completely blocked by microinjection of amphetamine, fenfluramine, and mazindol into the paraventricular nucleus of the hypothalamus (PVN). Deprivation-induced feeding was not blocked by amphetamine, fenfluramine, or mazindol microinjected into the PVN. Neither the feeding induced by 2-deoxyglucose nor its reversal by amphetamine were blocked by pretreatment with the beta-adrenergic antagonist, propranolol. Amphetamine and fenfluramine blocked both glucoprivic- and deprivation-induced feeding when microinjected into the perifornical region of the lateral hypothalamus. These data suggest that food consumption induced by 2-deoxyglucose treatment can be antagonized by anorectic drugs acting at recognition sites present in several hypothalamic nuclei, while deprivation-induced feeding acts through different receptor mechanisms which may be specific to the perifornical region of the lateral hypothalamus.

Glucose regulates [3H](+)-amphetamine binding and Na+K+ ATPase activity in the hypothalamus: a proposed mechanism for the glucostatic control of feeding and satiety.

Binding sites for [3H](+)-amphetamine in the hypothalamus may mediate the anorectic actions of amphetamine and related phenylethylamines. To investigate further the role of these sites in the central control of appetite, the binding of [3H](+)-amphetamine to the hypothalamus and brainstem was measured following food deprivation and refeeding, the onset of genetic obesity, or the administration of 2-deoxy-D-glucose. Food deprivation for 24 to 72 hours reduced the Bmax for [3H](+)-amphetamine binding in the hypothalamus and brainstem but not in other brain areas or peripheral tissues. The decrease in hypothalamic and brainstem [3H](+)-amphetamine binding observed following food deprivation was time-dependent and rapidly reversed by brief refeeding with either rat chow or a 10% glucose solution. Moreover the changes in [3H](+)-amphetamine binding were highly correlated to corresponding alterations in blood glucose concentration. Furthermore, D-glucose, but not L-glucose increases the number of hypothalamic [3H](+)-amphetamine binding sites when administered in vivo or when added to hypothalamic slices in vitro. These data suggest that the [3H](+)-amphetamine binding site in the hypothalamus and (or) brainstem may be coupled to a central "glucostat."

Glucostatic regulation of (+)-[3H]amphetamine binding in the hypothalamus: correlation with Na+,K+-ATPase activity.

Preincubation of rat hypothalamic slices in glucose-free Krebs-Ringer buffer (37 degrees C) resulted in a time-dependent decrease in specific (+)-[3H]amphetamine binding in the crude synaptosomal fraction prepared from these slices. The addition of D-glucose resulted in a dose- and time-dependent stimulation of (+)-[3H]amphetamine binding, whereas incubation with L-glucose, 2-deoxy-D-glucose, or 3-O-methyl-D-glucose failed to increase the number of (+)-[3H]amphetamine binding sites. Ouabain potently inhibited the glucose-induced stimulation of (+)-[3H]amphetamine binding, suggesting the involvement of Na+,K+-ATPase. Preincubation of hypothalamic slices with glucose also resulted in an increase in Na+,K+-ATPase activity and the number of specific "high-affinity" binding sites for [3H]ouabain, and a good correlation was observed (r = 0.89; P less than 0.02) between the glucose-stimulated increase in (+)-[3H]amphetamine and [3H]ouabain binding. Similar increases in (+)-[3H]amphetamine binding, [3H]ouabain binding, and Na+,K+-ATPase activity were observed in the hypothalamus after parenteral administration of glucose to rats. The administration of anorectic doses of amphetamine (0.1-5.0 mg/kg of body weight) also increased Na+,K+-ATPase activity in the hypothalamus. These data suggest that the (+)-[3H]amphetamine binding site in hypothalamus, previously linked to the anorectic actions of various phenylethylamines, is regulated both in vitro and in vivo by physiological concentrations of glucose. Glucose and amphetamine appear to interact at common sites in the hypothalamus to stimulate Na+,K+-ATPase activity, and the latter may be involved in the "glucostatic" regulation of appetite.