Influence of sun irradiance and water availability on lichen photosynthetic pigments during a Mediterranean summer

This study was carried out to investigate changes in lichen photosynthetic pigments induced by different combinations of light irradiance and water availability during a Mediterranean summer. To this purpose, thalli of three epiphytic lichens with a markedly different ecology concerning photo-hygrophytism, namely Evernia prunastri (hygro-mesophytic), Flavoparmelia caperata (mesophytic) and Xanthoria parietina (xero-mesophytic), were transplanted for 30 days to N- and S-facing cardinal exposures in central Italy. To investigate the effect of thallus hydration, at each cardinal exposure 50% of thalli were hydrated daily with deionised water. The results showed that changes in the concentrations of photosynthetic pigments are species-specific and consist in a general depression of photosynthetic pigments only in the hygro-mesophytic species E. prunastri. The pattern of photosynthetic pigments was also investigated in spontaneous samples along contrasting aspects. In this case, X. parietina from S-facing slopes, adapted to direct solar influx, showed higher pigment content than N-facing thalli; F. caperata and E. prunastri avoid direct extreme solar radiation and assimilation pigments were influenced more by the shadowing of tree canopies than by the cardinal exposure. The influence of drought on lichen photosynthetic pigments in the Mediterranean area is discussed.     

Locomotor and peripheral effects of sibutramine modulated by 5-HT2 receptors

Sibutramine has been described as an anti-obesity drug with the ability to inhibit serotonin (5-HT), noradrenaline, and dopamine re-uptake, but without affinity to histamine and muscarinic receptors. On the other hand, cyproheptadine antagonizes serotonin 5-HT(2A), 5-HT(2B), and 5-HT(2C), histamine H1, and muscarinic (M) receptors. There are many reports concerning the influence of sibutramine on central serotoninergic pathways. In this study, we suggest that peripheral pathways may also be involved in the serotoninergic effects of sibutramine. In vivo experiments were undertaken to investigate the serotoninergic effects of sibutramine on body mass, the glycogen concentration in the diaphragm of rats, and locomotor behaviour. Rats were submitted to oral treatment with sibutramine, cyproheptadine, or sibutramine applied in combination with cyproheptadine, for a period of 2 months to investigate the 5-HT2 effects of sibutramine on these parameters. As the results demonstrated, the lower increase in body mass and the increased glycogen levels in the diaphragm muscle of rats treated with sibutramine seem to be modulated by 5-HT2 receptors, since these effects were completely antagonized by cyproheptadine in the group treated with the 2 drugs co-applied. Furthermore, the behavioural results also suggest that mechanisms modulated by 5-HT2 receptors are involved in the increase of locomotion in the rats treated with sibutramine, since the effect did not occur in the rats treated with sibutramine co-applied with the 5-HT2 receptor antagonist, cyproheptadine. The results suggest that sibutramine modifies energy-related parameters such as body mass, diaphragm glycogen, and locomotor behaviour in rats via 5-HT2 serotoninergic pathways.     

Postharvest chilling induces oxidative stress response in the dwarf tomato cultivar Micro-Tom

Oxidative stress is involved in the response of Lycopersicon esculentum fruits (cultivar Micro-Tom) to chilling. Changes in activated oxygen scavenging enzymes, superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6), ascorbate peroxidase (APX, EC 1.11.1.11), and glutathione reductase (GR, EC 1.6.4.2) were examined during ripening after postharvest chilling. Also, lipid peroxidation, respiration, and pigment contents were determined. These parameters were affected by chilling, especially the lycopene content and the respiration rate that showed a high value when the fruits were transferred to higher temperatures. CAT activity increased the day after the fruits were re-warmed, while the activity of GR was higher in the chilled than in the non-chilled green fruits. Lipid peroxidation was more evident at the 'pre-chilled' yellow and red fruits. APX and SOD were not affected by previous chilling in ripening fruits. These results indicate that oxidative stress is generated by conservation at 4°C. The antioxidant response of tomato fruit could be mediated by CAT and GR but not by SOD or APX. Moreover, CAT seemed to respond to the increase in the respiration rate.     

Non-formal education for schistosomiasis prevention: the experience of the Museu Arqueológico de Central, Bahia, Brazil

The activities described here form part of an extensive programme in place in the Regi?o Arqueológica de Central, state of Bahia, Brazil. After malacological and socio-environmental surveys in the area, a strategy comprising formal and non-formal education with an emphasis on schistosomiasis prevention was developed, introduced, and evaluated. Interviews were conducted of 142 students and 11 teachers, totalling 11 classes at six primary schools. On the basis of those interviews, four display cases and seven panels were prepared. In addition a table was set up where students could participate directly on the subject, drawing and recognising the factors involved in the schistosomiasis cycle. The exhibition was held at the Museu Arqueológico de Central. The endeavours of this paper underline the importance of health education as well as exhibitions to disease prevention activities.     

A new genus and species of opisthogonimid (Digenea) of Liophis anomalus (Serpentes: Colubridae) from Uruguay

During a study on the helminth fauna of Liophis anomalus specimens deposited in the Reptile Collection of the Secci6n Zoología Vertebrados, Facultad de Ciencias, Uruguay, a new genus of Opisthogoniminae was found. Paracotyletrema n. gen. is described from the buccal cavity and esophagus of specimens from Departamento de Flores, Uruguay. This new genus differs from the other 2 Opisthogoniminae, Opisthogonimus and Westella, by having much smaller body size; maximum width at level of posterior end of oral sucker; oral sucker length more than one-fourth of body length; oral sucker and acetabulum separated by a distance of about the diameter of pharynx; cirrus pouch length more than half of body length; and testes in completely coincident zones. The type and only species, Paracotyletrema poncedeleoni n. gen., n. sp., is defined by the following diagnostic characters: mean oral sucker length one-third to one-half of body length; cirrus pouch of about body length, contorted, mainly acetabular; large, round testes in nearly adjacent fields, and an ovary nearly adjacent to right testis. Besides the type locality, Paracotyletrema poncedeleoni has been found in L. anomalus specimens from the Departamentos of Artigas and Treinta y Tres; therefore, it has a widespread distribution in Uruguay.     

Effect of indole acetic acid administration on the neutrophil functions and oxidative stress from neutrophil, mesenteric lymph node and liver

This study was done to investigate the effect of the in vivo administration of indole acetic acid (IAA) on the neutrophil function, the activities of antioxidants enzymes in neutrophils, the mesenteric lymph node and on the oxidative stress in liver and plasma. The animals received subcutaneous administration of IAA in a phosphate-buffered saline (the control group received only the phosphate-buffered saline). The other groups received IAA at concentrations of 1 mg (T1), 2 mg (T2) and 18 mg (T3) per kg of body mass per day. Administration of IAA in both treatments T2 and T3 promoted a significant rise in the phagocytic capacity of neutrophils (by 51%), in comparison with the control. Another alteration was observed in antioxidant enzyme activities of the neutrophil and lymph node. But in the liver, the treatments imposed a significant decrease in the activity of catalase of 19% and 30% for T2 and T3, respectively, in comparison with the control. A similar effect was observed in the activity of hepatic glutathione peroxidase for T3 where a significant decrease of 31%, compared with the control, was obtained. The IAA did not show another significant alteration of the activities of superoxide dismutase and glutathione reductase activities in liver. The hepatic lipid peroxidation level, available by reactive products with thiobarbituric acid, has shown a significant decrease of 27% and 29% with T1 and T3 respectively, in comparison with the control. IAA treatment did not show a significant alteration in reduced glutathione contents in comparison with the liver and plasma controls. In conclusion, the IAA administration has a good potential animal utilization for increasing the phagocytic capacity with no prooxidant effect.