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Recently, it has been proposed that neurofibromin (NF1) forms a binding complex with amyloid precursor protein (APP) that interacts with the dopamine D3 receptor (D 3R). In the present study we investigated whether the absence of the D 3R is correlated to modifications in the expression of both NF1 and APP. Quantitative real-time PCR analyses of both transcripts showed that NF1 mRNA levels were significantly reduced whereas APP levels were strikingly increased in D 3R knock-out (D 3R KO) as compared to wild type (WT) mice brains. Western blot analyses using mice whole brains produced comparable results with those obtained by mRNA measurements. Moreover, immunohistochemical analyses revealed a similar brain regional distribution of APP protein in the hippocampus, in the cerebral and cerebellar cortex of D 3R KO mice. Conversely, hippocampal NF1 immunoreactivity did not seem to be affected by the absence of D3Rs. Further analyses confirmed that regional NF1 protein expression in the hippocampus was not affected by the absence of the D 3R, whereas APP levels were still increased in this specific brain region. In conclusion, these results show the existence of a correlation among the D 3R, NF1 and APP in mice brains and thus show the regional-specific regulation of NF1 in brains of D 3R KO, which may contribute to gain insights into the comprehension of novel underlying mechanisms that regulate brain function. © Springer Science+Business Media, LLC 2010.

Detailed study of the temporal and spatial patterns of planktonic foraminiferal assemblages was performed on seven eastern Mediterranean deep-sea cores to evaluate differences and similarities in their stratigraphic records during the Eemian sapropel S5 interval. Changes in the succession of planktonic assemblages are very similar in all investigated sapropel S5 sequences. Analyses carried out on the 63 and 150 mu m size fractions indicate that during this time interval, size does not significantly affect the stratigraphic patterns. Benthic assemblages were studied at three sites, where their succession of changes was concordant but locally different. In this framework, comparison of S5 sapropels layers from different areas of the eastern Mediterranean suggests that the onset of the dark colour does not occur in the same stratigraphic position at a regional scale, whereas the absence/drastic reduction of benthic foraminifera within sapropel intervals appears to be a "time equivalent" event and corresponds to the last local occurrence of Globorotalia inflata. (c) 2005 Elsevier B.V. All rights reserved.

Calcareous nannoplankton, diatoms and organic-walled dinoflagellate cysts from seven eastern Mediterranean sediment cores were investigated to clarify the climatic and paleoceanographic conditions that influenced the deposition of sapropel S5 during Marine Isotopic Stage 5e. Warming of surface waters during S5 deposition is indicated by the high abundance of the calcareous nannofossil "small" Gephyrocapsa group, the presence of the dinoflagellate species Spiniferites mirabilis, Spiniferites pachydermus, Lingulodinium machaerophorum and Polysphaeridium zoharyi, and the tropical-subtropical diatom Pseudosolenia calearavis, Chaetoceros resting spores, Rhizosolenids and Thalassionema group. Increased productivity accompanied S5 deposition as evidenced by a general decrease in abundance of calcareous nannofossil superficial species and a coeval increase of dinocysts and diatoms. The productivity increase is further supported by an increase of the deep dwelling calcareous nannofossil species Florisphaera profunda. Stratification of near-surface waters is recorded by the presence of the dinocyst species L. machaerophorum and P zoharyi together with the co-occurrence of the diatom Chaetoceros resting-spore group, Thalassionema frauenfieldii, and Thalassionema nitzschioides var. parva, which reflect transport of neritic waters off-shore, and by the presence of some freshwater and transport-related diatom taxa (Cyclotella, Diatomella and Diploneis). Gradual shoaling of the nutricline and a gradual weakening of water stratification at the end of S5 deposition is indicated by an increase in the deep dwelling calcareous nannoplankton species Gladiolithus flabellatus, which suggests a less-deep niche compared to the deeper dwelling F profunda. Time transgressive variations in the distribution of the calcareous nannofossil Emiliana huxleyi and changes in the abundances of Gephyrocapsa oceanica, small Gephyrocapsa, G. flabellatus, and of the dinocysts R zoharyi and L. machaerophoru

Some studies show that pesticides affect neurological functions, although existing data are contradictory. The aim of this research has been to measure the difference in motor execution and the activity of cholinesterase in adolescents after different degrees of exposure to pesticides. Our hypothesis states that motor functions will diminish in the population with greater exposure to this kind of environmental contamination. In this present work, we have studied adolescents from three district areas, each with different rates of environmental exposure to pesticides. Neuro-conductivity tests have been performed in order to evaluate cognitive execution, and biochemical tests have been carried out so as to quantify the levels of erythrocyte and plasmatic Acetyl-cholinesterase. The conductivity evaluation was carried out by means of a standard neurological and clinical case study; the study of Digits (it evaluates short-term memory) and the study of Digits and Symbols of the Wechsler Intelligence Scale for Children (it evaluates the codification of visual perceptions) and the Lewis study of Control of Digits (it evaluates sustained attention). In both the test that measured short-term memory (digits) and in the test that measured the codification of visual perceptions (digits and symbols), the adolescents from the area with the greatest exposure presented a poorer level of execution than the students from areas of lesser exposure. The levels of plasmatic cholinesterase (an indicator of acute poisoning) were similar for the three populations and in all of them, the levels were within the normal range. On the other hand, the level of erythrocyte cholinesterase (an indicator of chronic poisoning) was below the normal values in the adolescents of the areas with greater exposure as compared to those in the areas of lower exposure, whose esrythrocyte cholinesterase value was within the normal range. These results seem to corroborate the original hypothesis, because the popula, Algunos estudios indican que los plaguicidas afectan la función neurológica, aunque existen datos contradictorios. El objetivo de esta investigación fue medir diferencias en la ejecución motora y en actividad colinesterasa en adolescentes según la exposición a plaguicidas. La hipótesis es encontrar funciones motoras disminuidas en la población más expuesta a esta contaminación ambiental. En este trabajo se han estudiado adolescentes procedentes de tres zonas con diferente grado de exposición ambiental a plaguicidas. Se realizaron pruebas neuronconductuales para evaluar la ejecución cognitiva y pruebas bioquímicas para cuantificar los niveles de Acetilcolinesterasa eritrocitaria y plasmática. La evaluación conductual se llevó a cabo mediante una Historia clínica neurológica estándar; la prueba de Dígitos (evalúa memoria a corto plazo) y la prueba de Dígitos y Símbolos de la Escala Wechsler de Inteligencia para Niños, (evalúa codificación de las percepciones visuales y la prueba de Vigilancia de Dígitos de Lewis (evalúa atención sostenida). Tanto en la prueba que medía memoria a corto plazo (dígitos), como la que medía codificación de las percepciones visuales (dígitos-símbolos), los adolescentes de la zona de mayor exposición mostraron una peor ejecución que los alumnos de las localidades con menor exposición. Los niveles de colinesterasa plasmática (indicador de intoxicación aguda) fueron similares en las tres poblaciones y en todas ellas se encontraba dentro del rango de normalidad. Por otra parte, la colinesterasa eritrocitaria (indicador de intoxicación crónica) se encontraba por debajo del límite inferior de normalidad los adolescentes de las localidades con mayor exposición en comparación a los de menor exposición, cuya colinesterasa eritrocitaria se encontraba dentro del rango de normalidad. Estos resultados parecen corroborar la hipótesis de partida ya que la población más expuesta es la que peor rendimiento tuvo mientras que la menos expuesta presentó mejore

Planktonic foraminiferal and calcareous nannofossil assemblages of three box-cores from the western-central part of the Mediterranean Ridge area were investigated and correlated. In particular we focused on the most significant faunal and floral signals recorded before, during and after sapropel SI deposition. The interval preceding S1 is characterised by an increasing trend of the two planktonic foraminiferal species, Globorotalia inflata and Truncorotalia truncatulinoides, that are usually related to a well developed cold and deep mixed layer. This change is supported also by the rarity of warm water coccolithophorid species and by the presence of the deep dwelling species Florisphaera profunda. The beginning of S1 is marked by the disappearance of G. inflata and T. truncatulinoides and by the significant increase in abundance of Globigerinoides ruber, especially the rosea variety usually considered indicative of warmer conditions. Warm water species increase also within the coccolithophorid assemblage, while the upwelling species Reticulofenestra spp. suddenly decreases and remains low across the whole sapropel interval. The sedimentary expression of the end of anoxia is the upper boundary of the oxidised level observed above S1 in the three box-cores. Across this boundary we detect a small but well defined increase of Braarudosphaera bigelowii, the decrease of warm water coccolithophorid species and the increase of Reticulofenestra spp. This boundary is marked also by the reoccurrence of the planktonic foraminiferal species G. inflata and Neogloboquadrina pachyderma dextral and by an evident decrease of G. ruber var. rosea, indicating the end of the Holocene Climatic Optimum and the beginning of a cold and wet phase, probably corresponding to the Atlantic-Subboreal continental transition. (C) 2002 Elsevier Science B.V. All rights reserved.