Seventeen elements were analysed in the organs and tissues of the variegated scallop Chlamys varia, from the Atlantic coast of France. Concentration levels were determined in scallops of different sizes sampled in contaminated (La Rochelle Bay) and clean (Re Island) sites. Greater concentrations of Ag, Al, Ce, Cr, La, Mo, Nd, Ti, and V were found in the digestive gland while As, Cd, Co, Cu, Mn,...

The relevance of cephalopods for fisheries and even aquaculture, is raising concerns on the relationship between these molluscs and environmental stressors, from climate change to pollution. However, how these organisms cope with environmental toxicants is far less understood than for other molluscs, especially bivalves, which are frontline models in aquatic toxicology. Although, sharing the sa...

The aim of this study was to evaluate the use of metal concentrations in clam organs to monitor metal contamination in coastal sediments. The concentrations of Cd, Cr, Cu, Hg, Ni, Pb, V, and Zn were measured in the kidneys, gonads, mantles, gills, digestive gland, and hearts of the infaunal clam Amiantis umbonella collected from a contaminated site near desalination and power plant discharges, ...

A cytochemical method allowing the localization and quantification of plasma membrane Ca2+-ATPase (PMCA) in frozen sections obtained from digestive gland cells of Mytilus galloprovincialis, Tapes tapes and Chamelea gallina, is presented. The method utilizes lead as a trapping agent of PO4(2-) ions released by Ca2+-ATPase activity. The amount of lead sulphide precipitate proportionally related t...

The aim of this study was to determine the lethal salinity (LC50) for the yellow clam Mesodesma mactroides (Bivalvia: Mesodesmatidae) and identify histopathological alterations that could be used to diagnose structural changes in clam tissue. Clams in two size classes (adults and juveniles) were placed in 10 L chambers and exposed to salinities of 35, 30, 25, 20, 15, 10, and 5 g/L. There were t...

Chitinolytic enzymes have an important physiological significance in immune and digestive systems in plants and animals, but chitinase has not been identified as having a role in the digestive system in molluscan. In our study, a novel chitinase homologue, named Ca-Chit, has been cloned and characterized as the oyster Crassostrea angulate. The 3998bp full-length cDNA of Ca-Chit consisted of 23b...

The salient features of the fine structure of the spore ofMinchinia chitonis (Lankester, 1885) Labbe, 1896 are reviewed. The morphological characteristics are similar to those of the spores of other members of the family Haplosporidiidae. particularly the hinged operculum covering the anterior orifice, the "spherule" and the haplosporosomes. October 1981. 43(10) clear understanding of the morph...

Molluscides have been used as one of the strategies to control schistosomiasis. Many plant extracts with molluscidal effects have been tested, but the action of the latex of Euphorbia splendens var. hislopii is considered the most promising because it meets the recommendations of the World Health Organization (WHO). The objective of this study was to determine the lethal dose and identify the e...

The African trypanosome Trypanosoma brucei, which causes sleeping sickness in humans and Nagana disease in livestock, is spread via blood-sucking Tsetse flies. In the fly's intestine, the trypanosomes survive digestive and trypanocidal environments, proliferate, and translocate into the salivary gland, where they become infectious to the next mammalian host. Here, we show that for successful su...

Digestive cells of hydra contain accumulations of irregular particles, 200 to 300 A in diameter and of low density, that stain with lead hydroxide (11). These particles were observed in clear areas of hyaloplasm and were often partially or completely enclosed by mitochondria. Similar dense particles in the hyaloplasm of digestive cells have been identified as glycogen (7, 16), although no assoc...