Calbindin-D28K and the peptidergic neuroendocrine system in rat gut: an immunohistochemical study

Calbindin-D28K was immunohistochemically localized in myenteric and submucosal plexuses throughout the rat intestine. Calbindin-D28K immunoreactivity was found in about half of myenteric neurons and in more than 90% of submucosal neurons. Calbindin-D28K was also observed in nerve processes running inside ganglia, muscle layers and lamina propria. No correlation could be established between the presence of calbindin-D28K and the distribution of neuropeptides localized in this study (VIP, enkephalin, somatostatin and substance P). In addition, some endocrine-like cells of the ileum were calbindin-D28K-positive. Half of these endocrine cells also contained neurotensin but none of the other neuropeptides investigated.Journal ArticleResearch Support, Non-U.S. Gov'tSCOPUS: ar.jFLWNAinfo:eu-repo/semantics/publishe

Hydric properties of high charge, halloysitic clay soils from the tropical South Pacific region

In humid tropical areas, the spatial distribution of volcanic ash soils generally follows a weathering sequence in which halloysite-rich soils represent an intermediate weathering stage between young soils (Andosols) and strongly weathered soils (Ferralsols). Strongly weathered soils rich in crystalline iron oxide and kaolinite are known for their fast and free drainage as well as for their large water retention in micropores, caused by micro-aggregation. They exhibit, however, low available water. Here, we report on similar properties in halloysitic soils derived from volcanic ash, in Tongatapu island, Kingdom of Tonga, Pacific. The soils are fine clayey (68-96% clay) and contain three dominant constituents: humic substances, halloysite and iron oxide (6-12%). They exhibit a relatively large reserve in alkaline and alkaline-earth cations confined to the clay fraction, and more specifically to exchangeable and non-exchangeable cations associated with high charge clay minerals detected by XRD as smectite. Whatever the soil layer and the soil organic matter content, the soil materials have exceptionally high saturated hydraulic conductivity, ranging from 7 to 85 cm h(-1), and large water retention (30-40%) at low hydric potential (<- 15,000 hPa). The water properties show that these soils are strongly micro-aggregated. We propose that they are caused by specific interactions between halloysite and high surface area iron oxide. (c) 2006 Published by Elsevier B.V

Comparison between rat brain calbindin- and calretinin-immuno-reactivities.

Journal ArticleResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe

Calbindin D28k in mammalian intestinal absorptive cells: immunohistochemical evidence

Calbindin D28k and D9k are two cytosolic calcium-binding proteins abundant in intestinal absorptive cells which appear to play a role in calcium translocation. Until today, calbindin D28k was found in avian and reptilian absorptive cells but not in mammalian ones. We have described the presence of calbindin D28k-immunoreactivity in intestinal absorptive cells of pig and jerboa (Jaculus jaculus). Pig calbindin D28k-immunoreactive absorptive cells were prominent in duodenum, they were scattered along the villi and nearly absent in the crypts. Jerboa labelled absorptive cells were located along the colonic mucosal surface. No calbindin D28k could be detected in mouse, rat and goat absorptive cells. Topography of calbindin D28k absorptive cells was compared with calbindin D9k distribution. Our results confirmed the data of the literature showing a gradient of labelling increasing from the crypt to the top of the villus and no positive endocrine cell. Young (48 h old) pigs did not expressed calbindin D28k in absorptive cells although calbindin D9k was detected. Calbindin D28K was also observed in endocrine cells which were numerous in pig and goat duodenum and very rare in mouse and jerboa. Western blot experiments confirmed the presence of calbindin D28k in the adult pig intestine, in the jerboa colon and the absence of cross-reactivity between calbindin D28k antibody and calbindin D9k.Comparative StudyJournal ArticleResearch Support, Non-U.S. Gov'tFLWNAinfo:eu-repo/semantics/publishe

NITROGEN AND DISSOLVED CARBON BALANCES IN THE AZHUREV CONSTRUCTED WETLAND

International audienceThe Azhurev horizontal-flow constructed wetland is a large-scale demonstration wetland built at the outlet of the Grand Reims wastewater treatment plant (WWTP). Three 20,000 m 2 basins (rectangular shape with different depth distribution within each basin) have been created: the initial vegetation (mainly P. australis, S. lacustris and G. maxima) density was also different in each basin. Their aim is to polish a part of the treated wastewater (250 m 3 /h) from the Grand Reims WWTP, as well as to treat part of the Grand Reims stormwater. The wetland has been operated since July 2017. Flowmeters have been installed at the inlet and the outlet of each basin, as well as conductimeters and temperature sensors. Sampling campaigns have been organized on a monthly basis: the samples have been collected at the inlet and exit of each basin as well as in the basins with an aquatic drone. They have been analysed in terms of nitrogen species (total dissolved nitrogen, nitrates, nitrites, ammonia) and dissolved inorganic and organic carbon. The dissolved organic matter has been further characterized by optical methods (synchronous fluorescence and UV-visible spectroscopy). Plants have been collected and their carbon and nitrogen content has been determined. There is no infiltration from the basins to the aquifer, as evidenced by the hydraulic balance. The results obtained after more than one year of operation show a global nitrogen removal rate of 50% (equivalent for nitrates and ammonia). An increase of the dissolved organic carbon has been observed between the inlet and the outlet in summer and fall: this is due to anaerobic decomposition of aquatic plants underneath a thick layer of L. minor, which has gradually covered the basins. In November 2018, a large maintenance of the site has been set up with plant cutting and removal, in order to promote vegetation development in spring. The presentation will describe the complete carbon and nitrogen balance over the two years of operation of the wetland and compare the basin efficiency in function of the vegetation. BIO: N. Maurice is a Ph.D student with a soil and water remediation background

Mise en œuvre d’une Zone Humide Artificielle pour le traitement de finition des eaux traitées de Grand Reims

International audienc