Seasonal differences in ventricular proliferation of adult Gallotia galloti lizards.

Lizards present neuronal production throughout the telencephalon in their adult state, both naturally and after experimentally induced brain lesions. As in birds, lizards present seasonal behavioural variations. In birds, such variations have been shown to alter neuronal production. In birds and mammals, lack of stimuli or exposure to stress interferes with adult neurogenetic capacity. The effect of this type of study has not been performed with lizards. In the present study we used bromodeoxyuridine to label dividing cells in the ventricular walls of Gallotia galloti lizards during all four seasons and we investigated the effect of captivity on such proliferation. We found that G. galloti presented a particular distribution that differed from that previously described in other reptiles with respect to regions of greater or lesser proliferative rate. In addition, proliferative rate varied seasonally, with greater production of cells in Spring and low production in Autumn and Winter. Proliferative rate was significantly lower throughout the telencephalon and during all seasons in those lizards kept in captivity as compared with wild animals, even though photoperiod and temperature were similar to natural conditions. Our results indicate that cell production in lizards is species-dependent, varies with seasons and is significantly reduced in captive animals.

Intraventricular injections of mesenchymal stem cells activate endogenous functional remyelination in a chronic demyelinating murine model.

Current treatments for demyelinating diseases are generally only capable of ameliorating the symptoms, with little to no effect in decreasing myelin loss nor promoting functional recovery. Mesenchymal stem cells (MSCs) have been shown by many researchers to be a potential therapeutic tool in treating various neurodegenerative diseases, including demyelinating disorders. However, in the majority of the cases, the effect was only observed locally, in the area surrounding the graft. Thus, in order to achieve general remyelination in various brain structures simultaneously, bone marrow-derived MSCs were transplanted into the lateral ventricles (LVs) of the cuprizone murine model. In this manner, the cells may secrete soluble factors into the cerebrospinal fluid (CSF) and boost the endogenous oligodendrogenic potential of the subventricular zone (SVZ). As a result, oligodendrocyte progenitor cells (OPCs) were recruited within the corpus callosum (CC) over time, correlating with an increased myelin content. Electrophysiological studies, together with electron microscopy (EM) analysis, indicated that the newly formed myelin correctly enveloped the demyelinated axons and increased signal transduction through the CC. Moreover, increased neural stem progenitor cell (NSPC) proliferation was observed in the SVZ, possibly due to the tropic factors released by the MSCs. In conclusion, the findings of this study revealed that intraventricular injections of MSCs is a feasible method to elicit a paracrine effect in the oligodendrogenic niche of the SVZ, which is prone to respond to the factors secreted into the CSF and therefore promoting oligodendrogenesis and functional remyelination.

Effect of age on vanadium nephrotoxicity in rats.

The present study was designed to assess potential age dependent differences of vanadium nephrotoxicity in the rat following parenteral administration of vanadate. Young (22 days) and adult (62 days) male Sprague-Dawley rats received i.p. injections of sodium orthovanadate at 10 mg/kg/day for 8 consecutive days. Two additional groups of control rats received i.p. injections of 0.9% saline during the same period. Significant age-differences were found in most of the parameters used as indicators of nephrotoxicity in young and adult rats, with adverse renal effects being more severe with age. Vanadium-induced morphologic changes in the kidney were also more pronounced with age. These findings agree with a higher renal concentration of vanadium in the group of adult rats treated with vanadate than in the vanadate-untreated group. The current results can be of concern if in the future, vanadium compounds can be administered in the treatment of diabetic patients.

Levels of metals in soils of Alcalá de Henares, Spain: human health risks.

The concentrations of aluminium (Al), arsenic (As), beryllium (Be), cadmium (Cd), chromium (Cr), mercury (Hg), manganese (Mn), nickel (Ni), lead (Pb), tin (Sn), thallium (Tl), vanadium (V), and zinc (Zn) were determined in soil samples collected in Alcalá de Henares (Madrid, Spain). Human health risks derived from metal inhalation and ingestion of soils were also assessed. For noncarcinogenic risks, the current levels of metals were usually lower than those considered as safe for the general population. With respect to the potentially carcinogenic elements As, Be, Cd, and Cr, the concentrations of Be, Cd, and Cr were lower than the reference values, while the average As concentration (3.4 microg/g) was higher than the safety limit for risk cancer. In general terms, the potential human health impact of ingestion/inhalation through soils of the analyzed elements seems to be rather small.

Monitoring metals in the vicinity of a municipal waste incinerator: temporal variation in soils and vegetation.

The aim of this study was to determine the temporal variation in the concentrations of arsenic (As), beryllium (Be), cadmium (Cd), chromium (Cr), manganese (Mn), mercury (Hg), nickel (Ni), lead (Pb), tin (Sn), thallium (Tl), vanadium (V) and zinc (Zn) in soil and vegetation near an old municipal solid waste incinerator (MSWI). In October 1997, 24 soil and 24 herbage samples were collected at the same sampling points in which samples were also taken in October 1996. With the exception of an increase in the levels of Be and Ni, no significant differences in soils between both surveys were found; only Cr and V (decreases) and Hg (increase) showed significant variations in herbage samples during the last year. The concentrations of most elements in soil and vegetation samples collected near the MSWI are within the ranges previously reported for soil and vegetation in the vicinity of MSWIs.

Congener profiles of PCDD/Fs in soil and vegetation samples collected near to a municipal waste incinerator.

Recently, we measured the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) in soil and herbage samples collected in the vicinity of a municipal solid waste incinerator (MSWI) from Tarragona (Catalonia, Spain). Since these concentrations could be increased by the presence of other emission sources of PCDD/Fs in the same area in which the MSWI is placed, the main goal of the present study was to determine the PCDD/F congener profiles in the soil and vegetation samples collected in 1996 and again in 1997 near to the facility and to compare with those from samples collected in a close area outside of direct emissions of the plant. From an accurate inspection of the PCDD/F congener profiles, it was concluded that PCDD/F emissions from the MSWI here examined are neither the only nor the main responsible for the presence of PCDD/Fs in the samples of environmental matrices collected in the area under direct influence of the plant.

PCDDs and PCDFs in food samples from Catalonia, Spain. An assessment of dietary intake.

Food samples from local markets and supermarkets of Tarragona (Catalonia, Spain) were analyzed for PCDD/F concentrations. On lipid basis, PCDD/F levels in meat, fish, eggs, and fats and oils were similar or lower than those found in other countries. By contrast, in general terms PCDD/F levels in milk, vegetables, and cereals showed higher levels than those previously reported. The total dietary PCDD/F intake by the population of Tarragona was estimated to be 210 pg I-TEQ/day. This value is higher than the dietary intake of PCDD/Fs found in a number of surveys from other countries. However, when total dietary intake of PCDD/Fs was calculated including only fish and seafood, meat, milk and dairy products, eggs, and fats and oils, a dietary intake of PCDD/Fs of 117 pg I-TEQ/day was obtained. This intake is in the same range than that reported for different regions and countries. The results of the present study show that food groups such as vegetables, fruits, and cereals should not be excluded to estimate the total dietary intake of PCDD/Fs by general populations, especially in those countries and/or regions in which their consumptions are notable.

Assessment of baseline levels of PCDD/F in soils in the neighbourhood of a new hazardous waste incinerator in Catalonia, Spain.

In order to determine the baseline contamination by polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) in an area from Catalonia (Spain), which will be under the influence of a new hazardous waste incinerator, PCDD/F concentrations were measured in 40 soil samples collected in the vicinity of the facility now under construction. Thirty samples represented rural soils and 10 samples urban soils. PCDD/F concentrations ranged between 0.08-8.4 ng I-TEQ/kg for rural soils and 0.63-24.2 ng I-TEQ/kg for urban soils. The mean value for the 40 samples was 1.64 ng I-TEQ/kg (dry matter). The current PCDD/F levels and profiles are comparable to those found in soils from other countries. The PCDD/F concentrations found in this study show that at present the contamination by PCDD/F in soils of the examined area is rather low.

Atmospheric deposition of PCDD/Fs near an old municipal solid waste incinerator: levels in soil and vegetation.

The levels of polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) were determined in soil and vegetation samples taken from 24 sites in the vicinity of an old municipal solid waste incinerator (San Adrià del Besòs, Barcelona, Spain). Duplicate samples were collected within a radius of 3 km from the stack. PCDD/F concentrations in soils ranged from 1.22 to 34.28 ng I-TEQ/kg (d.m.) with median and mean values of 9.06 and 12.24 ng I-TEQ/kg, respectively. In turn, the levels of PCDD/Fs in vegetation samples ranged from 0.33 to 1.98 ng I-TEQ/kg (d.m.), with median and mean values of 0.58 and 0.70 ng I-TEQ/kg, respectively. Although the present PCDD/F concentrations in soil samples were higher than those recently found in soils taken near other incinerators from Catalonia, they are of the same order of magnitude than the levels of these pollutants found in incinerators from other countries. By contrast, the concentrations of PCDD/Fs in herbage samples were comparable to those found in recent surveys carried out in Catalonia.

Levels of PCDD/Fs in soil samples in the vicinity of a municipal solid waste incinerator.

Polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) were determined in 24 soil samples collected near a municipal solid waste incinerator (Tarragona, Catalonia, Spain). Soil samples were obtained at various sites within 1.5 km from the stack. Total PCDD/F concentrations ranged from 0.225 to 5.80 ng TEQ/kg dry matter (d.m.) with a median value of 0.799 ng TEQ/kg and a mean value of 1.080 ng TEQ/kg. No remarkable PCDD/F contamination was found. The results were consistent and even lower than those reported in other international studies. Principal Component Analysis and hierarchical cluster analysis were used to compare these soil samples with a set of 10 additional samples collected outside the influence of the plant. Principal Component and hierarchical cluster analyses of soils in the vicinity of the incinerator provide patterns of PCDD/Fs quite similar from those obtained in soils collected far from the influence of that facility.

Evaluating the environmental impact of an old municipal waste incinerator: PCDD/F levels in soil and vegetation samples.

In order to determine the temporal variation in the levels of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in the vicinity of an old municipal solid waste incinerator (MSWI) (S. Adrià del Besòs, Barcelona, Spain), 24 soil and vegetation samples were collected at the same sampling points in which samples had been taken 1 year before. Each sample was analyzed for PCDDs and PCDFs by high-resolution gas chromatography/high-resolution mass spectrometry. While in the previous study PCDD/F concentrations in soil ranged from 1.22 to 34. 28 ng I-TEQ/kg (median and mean values: 9.06 and 12.24 ng I-TEQ/kg), in the present study, PCDD/F levels ranged from 1.33 to 54.23 ng I-TEQ/kg (median and mean values: 11.85 and 14.41 ng I-TEQ/kg). On the other hand, in the previous study, PCDD/F levels in vegetation ranged from 0.33 to 1.98 ng I-TEQ/kg (median and mean values: 0.58 and 0.70 ng I-TEQ/kg), whereas in the present study, PCDD/F levels ranged from 0.32 to 2.52 ng I-TEQ/kg (median and mean values: 0.82 and 0.97 ng I-TEQ/kg). During the last 12 months, PCDD/F levels increased in 16 of the 24 soil samples and in 17 of the 24 vegetation samples analyzed. However, no significant differences in the median I-TEQ concentrations of both studies were found either in soil or vegetation samples.

PCDD/F levels in the vicinity of an old municipal solid waste incinerator: temporal variation in soils

In order to determine the temporal variation in the levels of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in soils in the vicinity of an old municipal solid waste incinerator (Montcada, Barcelona, Spain), in 1997 we collected 24 soil samples at the same sampling points in which samples were taken 1 year before. Each sample was analyzed for PCDDs and PCDFs by GC/MS. While in the previous study PCDD/F concentrations ranged from 0.30 to 44.26 ng TEQ/kg (dry matter), (median and mean values: 3.52 and 6.91 ng TEQ/kg), in the present study PCDD/F levels ranged from 0.15 to 29.27 ng TEQ/kg (median and mean values: 2.56 and 4.47 ng TEQ/kg). PCDD/F concentrations decreased in 14 of the 24 soil samples, while the remaining 10 samples showed increases of different orders. No statistically significant differences in PCDD/F levels according to the main wind directions in the area were noted. In both surveys, the highest PCDD/F concentrations were found 750 m from the stack to the south. The current levels of PCDD/Fs in soils, as well as those found in the previous survey are similar or even lower than PCDD/F concentrations reported for soil samples taken near to municipal solid waste incinerators from different places.

Study of adult neurogenesis in the Gallotia galloti lizard during different seasons.

In a previous study we found a seasonal distribution of cell proliferation (the first stage of adult neurogenesis) in the telencephalic ventricular walls of the adult Gallotia galloti lizard. The aim of the present work was to determine the influence of seasonality on the subsequent migration of the resulting immature neurons. We used wild animals injected with bromodeoxyuridine and kept in captivity within 30 days. To confirm the neuronal identity of these cells, we used double immunohistochemical 5-bromo-2'-deoxyuridine (BrdU) and doublecortin (DCX, an early neuronal marker) labeling, as well as autoradiography after the administration of methyl-[³H]thymidine ([³H]T). We found that: (1) the rate of cell division and/or migration from the ventricular walls varied with the season, especially in regions related with olfaction. (2) Immature neuron-like cells appeared to migrate in an apparently radial and tangential way towards different parts of the telencephalic parenchyma. (3) We did not observe ultrastructurally mature neurons until at least 90 days later, a period considerably greater than that reported for other species of vertebrates in similar studies.

Temporal variation of PCDD/PCDF levels in environmental samples collected near an old municipal waste incinerator.

In 1996 and 1997, the levels of polychlorinated dibenzo-p-dioxins (PCDDs) and dibenzofurans (PCDFs) were determined in soil and herbage samples taken from 24 sites in the vicinity of an old municipal solid waste incinerator (Montcada, Barcelona, Spain). To determine the temporal variation in the concentrations of PCDD/Fs, recently 24 soil and 24 herbage samples were again collected at the same sampling points and analyzed for PCDD/F levels. In the current survey, PCDD/F concentrations in soils ranged between 0.06 and 127 ng I-TEQ kg(-1) (dry matter), with median and mean values of 4.80 and 9.95 ng I-TEQ kg(-1) (dry matter), respectively. In turn, the levels of PCDD/Fs in herbage samples ranged from 0.40 to 1.94 ng I-TEQ kg(-1) (dry matter), with median and mean values of 0.86 and 0.95 ng I-TEQ kg(-1) (dry matter), respectively. The comparison with the data obtained in 1996 and 1997 show that while PCDD/F concentrations in herbage samples decreased substantially during the last two years, no significant differences in the levels of PCDD/Fs in soils were noted. On the other hand, the potential intake of polluted soils from the vicinity of the plant would not imply any significant health risk for the general population living in the area under influence of the facility.

Estudio de concordancia entre distintos dispositivos de medición de la presión arterial, en reclusos de un centro penitenciario / A study on the concordance between different blood pressure measurement devices among inmates of a correction centre

Objetivo: Evaluar la fiabilidad y valorar las diferencias existentes en las mediciones de la presión arterial obtenidas mediante distintos dispositivos de medida (esfigmomanómetro de mercurio, esfigmomanómetro aneroide y esfigmomanómetro digital) en reclusos de un centro penitenciario.Con los resultados obtenidos, podemos apreciar que existe una similitud en las medidas realizadas entre el esfigmomanómetro de mercurio y el esfigmomanómetro digital, presentando diferencias de medias que son superiores cuando se comparan estos dos aparatos, con respecto al esfigmomanómetro aneroide

Objective: To evaluate the reliability and assess the differences between blood pressure readings obtained with different measuring devices (mercury sphygmomanometer, aneroid sphygmomanometer and digital sphygmomanometer) among inmates of a correction centre.With the results obtained, we saw that there was a similarity in readings with the mercury and digital sphygmomanometers, with differences of means that were higher when these two devices were compared than with the aneroid sphygmomanometer