| bioaccumulation and depuration of enteroviruses by the soft-shelled clam, mya arenaria. | low levels of feces-associated natural virus, simulating virus numbers estimated to exist in moderately polluted shellfish-growing waters, were used to evaluate the effectiveness of depuration as a virus depletion procedure in soft-shell clams. depuration effectiveness depended upon the numbers of virus bioaccumulated and whether virus was solids associated. virus uptake was greatest when viruses were solids associated and pollution levels were equivalent or greater than those likely to be found ... | 1979 | 229766 |
| isolation and characterization of vibrio parahaemolyticus from cape cod soft-shell clams (mya arenaria). | vibrio parahaemolyticus was isolated from soft-shell clams (mya arenaria) taken from 10 different clamming areas on cape cod, mass., during july and august 1972. direct plating on thiosulfate-citrate-bile salts-sucrose agar was found to be superior to either direct plating on vanderzant modified salt starch agar or enrichment with trypticase soy broth containing 7% salt for isolation from clam samples. morphological and biochemical characteristics of 33 isolates from 30 samples generally conform ... | 1975 | 1096817 |
| rickettsiae in the cytoplasm of gill epithelial cells of the soft-shelled clam, mya arenaria. | | 1991 | 2066581 |
| a method for the enumeration of poliovirus in selected molluscan shellfish. | a virus extraction procedure was developed and evaluated on five commercially important molluscan shellfish species: crassostrea virginica (eastern oyster), mya arenaria (softshell clam), mytilus edulis (blue mussel), mercenaria mercenaria (hardshell clam), and crassostrea gigas, (pacific oyster). shellfish tissue homogenates were spiked with poliovirus, extracted, and plaque assayed. mean virus recoveries were: c. virginica, 63.8%; m. arenaria, 42.1%; m. edulis, 67.3%; m. mercenaria, 48.3%; and ... | 1989 | 2559103 |
| a combination fluorescence assay and folin-ciocalteau phenol reagent assay for the detection of paralytic shellfish poisons. | paralytic shellfish poison (psp) profiles of crude shellfish extracts were determined by linear gradient elution from a bio-rad ag-50-x4 strong cation-exchange resin mini-column. stx, gtx2 and gtx3 were detected by fluorescence assay. neostx and gtx1/gtx4 were detected with a folin-ciocalteau phenol reagent assay. the major toxicity associated with extracts of mytilus edulis and mya arenaria collected during a 1972 red tide off hampton, new hampshire, was due to the presence of gtx1/gtx4, with s ... | 1985 | 4024145 |
| soft-shell clam, mya arenaria, a convenient laboratory animal for screening pathogens of bivalve mollusks. | attempts to introduce infectious or foreign material into oysters and other bivalve mollusks usually involve force or trauma because of immediate, prolonged adduction of the tightly closing valves. the soft-shell clam, mya arenaria, is unable to seal its valves completely and relaxes readily, exposing soft tissue and a large siphon. this species is free from fouling organisms and is readily available at all seasons in the new england and mid-atlantic areas. suspensions of five strains of vibrio ... | 1971 | 4940871 |
| [on the presence of a substance similar to human a-antigen in mya arenaria l]. | | 1967 | 5627411 |
| characterization of two perkinsus spp. from the softshell clam, mya arenaria using the small subunit ribosomal rna gene. | sequence analysis and riboprinting of the small subunit ribosomal rna genes were used to characterize two morphologically different perkinsus species isolates from the gill (g117) and the hemolymph (h49) of the softshell clam, mya arenaria. sequence data of the polymerase chain reaction amplified ribosomal rna loci of g117 and h49 indicated that these genes are 1803 and 1806 base-pair long, respectively. a sequence similarity of > 98.9% was calculated among ribosomal rna sequences of the two iso ... | 1999 | 10461386 |
| discrimination between two perkinsus spp. isolated from the softshell clam, mya arenaria, by sequence analysis of two internal transcribed spacer regions and the 5.8s ribosomal rna gene. | the internal transcribed spacer (its-1 and its-2) regions and the 5.8s ribosomal rna gene of 2 perkinsus spp. (g117 and h49) originating from the softshell clam, mya arenaria, of the chesapeake bay were cloned and sequenced to obtain evidence for their genetic divergence. a high level of heterogeneity in both regions, probably resulting from deletions, insertions, and base substitutions, was evident from alignments of the sequences of the 2 isolates with published sequences of other perkinsus sp ... | 1999 | 10581614 |
| zoosporulation of a new perkinsus species isolated from the gills of the softshell clam mya arenaria. | a gill-associated perkinsus sp. isolated from the softshell clam (mya arenaria) is described as a new species, p. chesapeaki sp. nov. examination of the parasite in seawater cultures revealed life cycle stages and zoosporulation processes similar to those described for other species of the genus perkinsus. prezoosporangia developed thickened cell walls upon contraction of the cytoplasm and development of a distinctive clear area between the cell wall and the protoplast. successive bipartition of ... | 2000 | 10887658 |
| analysis of extracellular proteins of two perkinsus spp. isolated from the softshell clam mya arenaria in vitro. | biochemical characterization of the extracellular proteins (ecp) of two softshell clam perkinsus spp. cloned isolates, perkinsus chesapeaki isolate g-117 and perkinsus marinus h-49, was performed and compared to that of the oyster-derived p. marinus isolate p-1. g-117 and h-49 demonstrated distinct differences in enzyme activities; however, all three isolates shared common bands. substrate-impregnated gels showed h-49 to possess proteolytic activities while g-117 did not. inhibition studies reve ... | 2000 | 11026671 |
| identification of an e3 ubiquitin-protein ligase in the softshell clam (mya arenaria). | softshell clams (mya arenaria) were exposed to dioxin in controlled laboratory experiments in order to study their molecular response to dioxin exposure. a complementary dna (cdna) fragment with sequence similarity to e3 ubiquitin-protein ligase appeared to be upregulated in dioxin-exposed clams compared to controls. e3 covalently ligates ubiquitin onto a protein, targeting it for degradation. our findings suggest that the ubiquitin-mediated proteolytic pathway in the softshell clam may be activ ... | 2000 | 11460706 |
| lipid radical generation in polar (laternula elliptica) and temperate (mya arenaria) bivalves. | lipid peroxidation in laternula elliptica was assessed by detecting lipid radicals by electronic paramagnetic resonance. the values were compared with data from the temperate mud clam mya arenaria. lipid radical content was higher in the antarctic bivalve than in the temperate mud clam, even within the range of its habitat temperature. the rate of generation of lipid radicals was affected by the iron content in the samples. the iron content in individual samples of digestive glands in l. ellipti ... | 2002 | 12128059 |
| two epizootic diseases in chesapeake bay commercial clams, mya arenaria and tagelus plebeius. | declining chesapeake bay harvests of softshell clams, together with historical and emerging reports of epizootic diseases in mya arenaria, prompted a survey in summer 2000 of the health status of selected commercial clam populations. all sampled populations (8 m arenaria softshell clam, 2 tagelus plebeius razor clam) were infected by perkinsus sp. protozoans at prevalences ranging from 30 to 100% of sampled clams. nucleotide sequences for the internal transcribed spacer (its) region of the rrna ... | 2002 | 12152906 |
| a hect e3 ubiquitin-protein ligase with sequence similarity to e6ap does not target p53 for degradation in the softshell clam (mya arenaria). | numerous reports have raised the level of national concern that chemicals found in the environment may have adverse effects on the health of humans and wildlife. environmental exposure to pollutants, such as dioxin, has been implicated in gonadal tumor formation in maine softshell clams (mya arenaria). prevalence of these tumors is as high as 40% in some populations. although their etiology is still unknown, investigations into the mechanisms of tumor formation have revolved around a hypothesis ... | 2004 | 15288542 |
| sodium channel mutation leading to saxitoxin resistance in clams increases risk of psp. | bivalve molluscs, the primary vectors of paralytic shellfish poisoning (psp) in humans, show marked inter-species variation in their capacity to accumulate psp toxins (psts) which has a neural basis. psts cause human fatalities by blocking sodium conductance in nerve fibres. here we identify a molecular basis for inter-population variation in psp resistance within a species, consistent with genetic adaptation to psts. softshell clams (mya arenaria) from areas exposed to 'red tides' are more resi ... | 2005 | 15815630 |
| molecular, morphological, and experimental evidence support the synonymy of perkinsus chesapeaki and perkinsus andrewsi. | diverse analytical and experimental results confirm that two protistan parasites, perkinsus chesapeaki and perkinsus andrewsi, described separately as parasites of mya arenaria and macoma balthica clams sympatric in chesapeake bay, usa, represent a single species. ribosomal rna (rrna) internal transcribed spacer (its) regions, rrna large subunit (lsu) gene, and actin gene sequences were obtained from clonal perkinsus spp. cultured in vitro. although multiple polymorphic sequences were found in d ... | 2005 | 15927003 |
| partial purification and characterization of hemolysin from a psychrotrophic kanagawa-positive marine vibrio. | psychrotrophic kanagawa-positive marine vibrios were isolated from soft-shelled clams (mya arenaria) collected in yaquina bay, oreg. the 235 vibrio isolates obtained were screened for gram reaction and morphology, kanagawa reaction on wagastsuma agar, and response to selected biochemical tests. the vibrio selected for further study was grown in broth, and the hemolysin was precipitated from a cleared supernatant with solid ammonium sulfate. the hemolytic substance was partially purified by deae- ... | 1982 | 16345927 |
| germinoma in razor clam ensis arcuatus (jeffreys, 1865) in galicia (nw spain). | germinoma is a gonadal neoplasm originating from progenitor cells in germinal epithelium. over the last four decades it has been diagnosed in several species of marine bivalve molluscs but most consistently in some populations of mercenaria mercenaria and mya arenaria in north america. tissue sections of gonads from ensis arcuatus (family pharidae--superfamily solenacea), collected in ría de vigo (galicia-nw spain), revealed germinoma in both males and females. proliferating, undifferentiated, g ... | 2006 | 16905143 |
| [a study to assess the microbial contamination of mya arenaria clams from the north shore of the st lawrence river estuary, (québec, canada)]. | the aims of the present study were to assess the microbial quality of mya arenaria clams from the north shore of the st. lawrence river estuary and to validate various microbial indicator microorganisms of bivalve mollusks contamination. clams were collected from nine sites, including four harvesting sites closed by virtue of the canadian shellfish sanitation program (cssp). six contamination indicators (fecal coliforms, somatic coliphages, f-specific coliphages, fecal streptococci, clostridium ... | 2006 | 17110967 |
| arsenic bioaccessibility and speciation in clams and seaweed from a contaminated marine environment. | the bioaccessible concentration and speciation of arsenic (soluble in a gastrointestinal medium and available for absorption into the bloodstream) were determined in softshell clams (mya arenaria), harvested by local residents until 2005, and in seaweed (fucus sp.) from an arsenic-contaminated marine site in seal harbour, nova scotia, canada. bioaccessibility extractions to simulate the human gastrointestinal environment (ph 1.5 and glycine for 1h followed by pancreatin, bile extract and ph adju ... | 2007 | 17241645 |
| experimental cross-infections by perkinsus marinus and p. chesapeaki in three sympatric species of chesapeake bay oysters and clams. | in controlled laboratory transmission experiments, uniform doses of axenic in vitro isolate cultures of perkinsus marinus from a crassostrea virginica oyster, and of independent p. chesapeaki isolates from chesapeake bay mya arenaria and macoma balthica clams, were used to reciprocally challenge perkinsus sp.-free c. virginica, m. arenaria, and m. balthica experimental hosts. following mantle cavity inoculations, all 3 experimental hosts acquired high incidences (30 to 100%) of infections by eac ... | 2007 | 17718167 |
| assessment of haemic neoplasia in different soft shell clam mya arenaria populations from eastern canada by flow cytometry. | diagnosis of haemic neoplasia (hn) in the soft shell clam, mya arenaria, is often achieved by hematocytology and histology. since neoplastic cells display tetraploid dna contents, haemocyte cell cycle analysis was developed for use as a diagnosis tool. the aim of this study was to assess the application of a flow cytometry procedure of cell cycle analysis established for the common cockle, to clams and to evaluate different thresholds of value for the percentage of tetraploid cells for establish ... | 2008 | 18241883 |
| expression of homologues for p53 and p73 in the softshell clam (mya arenaria), a naturally-occurring model for human cancer. | homologues for human p53 (hsp53) and p73 (hsp73) genes were cloned and expression patterns for their corresponding proteins analysed in tissues from normal and leukemic softshell clams (mya arenaria). these are the first structural and functional data for p53 and p73 cdnas and gene products in a naturally occurring, non-mammalian disease model. core sequence of the predicted clam p53 (map53) and p73 (map73) proteins is virtually identical and includes the following highly conserved regions: the ... | 2001 | 11314008 |
| microbial utilization of the neurotoxin domoic acid: blue mussels (mytilus edulis) and soft shell clams (mya arenaria) as sources of the microorganisms. | the neurotoxin domoic acid is produced in quantity by the diatom pseudo-nitzschia multiseries and is released to the environment directly and indirectly via food chains. presumably there is a mechanism for the biodegradation and disposal of domoic acid and as bacteria are logical candidates for such an activity, a search for bacteria competent to carry out biodegradation of domoic acid was initiated. extensive trials with a wide variety of bacteria isolated mainly from muds and waters taken from ... | 1998 | 9741971 |
| soft-shell clam (mya arenaria) p53: a structural and functional comparison to human p53. | the tumor suppressor p53 regulates genes involved in progression through the cell cycle, dna repair, senescence or apoptosis in response to cell stress. dysregulation of p53 can result in uncontrolled cellular proliferation. invertebrate homologues to human p53 (hsp53) have been identified, including a putative p53 gene (map53) from the soft-shell clam (mya arenaria). predicted sequences for human and clam p53 proteins exhibit conservation in key domains. in light of this similarity, and the app ... | 2009 | 19121375 |
| isolation of the cdna and characterization of mrna expression of ribosomal protein s19 from the soft-shell clam, mya arenaria. | ribosomal proteins contribute to the regulation and activity of ribosomes, and hence, the translational activity of the cell. aberrant expression of ribosomal proteins has been linked to certain pathological conditions such as neoplasms. we have isolated and characterized a cdna for the ribosomal protein (rp) s19 from a marine bivalve, the soft-shell clam (mya arenaria), and we have examined its pattern of mrna expression in the ovary and testis. the s19 cdna contains a 450 nucleotide (nt) open ... | 1997 | 9332378 |
| molecular epizootiology of perkinsus marinus and p. chesapeaki infections among wild oysters and clams in chesapeake bay, usa. | perkinsus marinus and p. chesapeaki host ranges among wild chesapeake bay, usa, region bivalves were examined by surveying crassostrea virginica oysters and members of several sympatric clam species from 11 locations. perkinsus genus- and species-specific pcr assays were performed on dna samples from 731 molluscs, and species-specific in situ hybridization assays were performed on a selected subset of histological samples whose pcr results indicated dual or atypical perkinsus sp. infections. pcr ... | 2008 | 19244976 |
| detection of genotoxic substances in bivalve molluscs from the saguenay fjord (canada), using the sos chromotest. | few studies have employed bioassays to investigate the accumulation of genotoxins in aquatic biota that inhabit areas contaminated with industrial and municipal wastes. this study employed the sos chromotest, a short-term bacterial genotoxicity assay, to investigate the presence of genotoxins in bivalve molluscs from the saguenay fjord (canada). genotoxicity analyses were performed on dichloromethane extracts of mya arenaria and mytilus edulis collected downstream from several aluminum refinerie ... | 1997 | 9294028 |
| environmental effects and aquatic organisms: investigations of molecular mechanisms of carcinogenesis. | cancers of the reproductive system are among the leading causes of mortality in women in the united states. while both genetic and environmental factors have been implicated in their etiology, the extent of the contribution of environmental factors to human diseases remains controversial. to better address the role of environmental exposures in cancer etiology, there has been an increasing focus on the development of nontraditional, environmentally relevant models. our research involves the deve ... | 1997 | 9168012 |
| implications for the presence of transforming genes in gonadal tumors in two bivalve mollusk species. | studies were initiated on oncogene activation in two bivalve species with high frequencies of histologically identifiable gonadal neoplasms. pathological assessments identified epizootic seminomas and dysgerminomas in softshell clams (mya arenaria) from three maine estuarine sites contaminated by herbicides and in hardshell clams (mercenaria) from the indian river in florida, an area of potential citrus agrochemical exposure. nih3t3 transfection assays were used to examine dna isolated from thes ... | 1993 | 8319204 |
| differential gene expression of gamma-actin, toll-like receptor 2 (tlr-2) and interleukin-1 receptor-associated kinase 4 (irak-4) in mya arenaria haemocytes induced by in vivo infections with two vibrio splendidus strains. | immune function gene expression in mya arenaria haemocytes was evaluated following in vivo infection with vibrio splendidus lgp32-gfp and 7shrw. elongation factor 1alpha (ef-1alpha) with 2 (ef-2), after challenge with lgp32-gfp, and ef-1alpha with the ribosomal protein s-18, after challenge with 7shrw, were found to be the most stable housekeeping genes. using these internal controls and comparing the regulation induced by both strains, up-regulation of gamma-actin, down-regulation of tlr-2 and ... | 2010 | 20156478 |
| molecular analysis of bivalve tumors: models for environmental/genetic interactions. | an increase in both the numbers and types of tumors found in finfish and shellfish has been noted in the past several decades. in many cases, while the increase in tumor incidence can be correlated with increases in aquatic toxicant levels, causality cannot be definitively proven. one recent epidemiologic investigation identified the prevalence of gonadal cancers as high as 40% in softshell clams (mya arenaria) in maine and 60% in hardshell clams (mercenaria spp.) from florida. a second study of ... | 1994 | 7713040 |
| trace metal residues in shellfish from maryland waters, 1976-1980. | levels of seven heavy metal residues, arsenic, cadmium, chromium, copper, lead, mercury and zinc were monitored in samples of the american oyster (crassostrea virginica), the soft shell clam (mya arenaria), the hard shell clam (mercinaria mercinaria) and the blue crab (callinectes sapidus). samples were taken from the maryland section of the chesapeake bay and its tributaries over a five year period (1976-80). this study was undertaken to provide an estimate of a baseline for values of trace hea ... | 1984 | 6501792 |
| expression of mutant protein p53 and hsp70 and hsp90 chaperones in cockles cerastoderma edule affected by neoplasia. | high prevalence of disseminated neoplasia has been found in cockles cerastoderma edule of galicia (nw spain). disseminated neoplasia has been associated with high mortalities of various bivalve species. in vertebrates, proteins such as p53 and heat shock proteins (hsps) play important roles in carcinogenesis. the protein p53 has been detected in neoplastic cells of bivalve molluscs such as mytilus edulis, mytilus trossulus, mya arenaria, spisula solidissima, crassostrea rhizophorae and crassostr ... | 2010 | 20815330 |
| regime shift in a coastal marine ecosystem. | we demonstrate changes in ecosystem stable states in a coastal lagoon that are consistent with what a regime shift would hypothesize. in the nutrient-stressed ringkøbing fjord, denmark, a small change in one variable (salinity) facilitated by a change in sluice management, caused a sudden regime shift from a bottom-up controlled turbid state, into a top-down controlled clear-water state. the change in dominating pathway of organic matter production from pelagic turnover to benthic-pelagic coupli ... | 2008 | 18488611 |
| heat inactivation of hepatitis a virus and a norovirus surrogate in soft-shell clams (mya arenaria). | the effectiveness of different thermal treatments for inactivating two viruses in clams was evaluated. soft-shell clam digestive glands experimentally contaminated with hepatitis a virus (hav) or murine norovirus (mnv) were heated for 90, 180, or 300 seconds at 85°c or 90°c in glass vials or plastic bags with 200 g of soft-shell clam meat. inactivation was measured by plaque assay and real-time reverse-transcription (rt)-polymerase chain reaction assay. measured inactivation was similar using bo ... | 2010 | 21126194 |
| genotoxic stress-induced expression of p53 and apoptosis in leukemic clam hemocytes with cytoplasmically sequestered p53. | in nature, the soft shell clam, mya arenaria, develops a fatal blood cancer in which a highly conserved homologue for wild-type human p53 protein is rendered nonfunctional by cytoplasmic sequestration. in untreated leukemic clam hemocytes, p53 is complexed throughout the cytoplasm with overexpressed variants for both clam homologues (full-length variant, 1,200-fold and truncated variant, 620-fold above normal clam hemocytes) of human mortalin, an hsp70 family protein. in vitro treatment with eto ... | 2008 | 18245478 |
| relationships between intertidal clam population and health status of the soft-shell clam mya arenaria in the st. lawrence estuary and saguenay fjord (québec, canada). | the purpose of this study was to examine the impacts of anthropogenic activity on the health status of intertidal clam populations of the saguenay fjord and the st. lawrence estuary (québec, canada). clams were collected during low tide at sites subject to direct contamination and at sites far from human activity. clams were analyzed for tributyltin and dibutyltin total levels and toxic stress (glutathione s-transferase, gonadal lipid peroxidation and dna strand breaks), immunocompetence (phagoc ... | 2008 | 17825412 |
| permanent genetic resources added to molecular ecology resources database 1 june 2011-31 july 2011. | this article documents the addition of 112 microsatellite marker loci and 24 pairs of single nucleotide polymorphism (snp) sequencing primers to the molecular ecology resources database. loci were developed for the following species: agelaius phoeniceus, austrolittorina cincta, circus cyaneus, circus macrourus, circus pygargus, cryptocoryne × purpurea ridl. nothovar. purpurea, mya arenaria, patagioenas squamosa, prochilodus mariae, scylla serrata and scytalopus speluncae. these loci were cross-t ... | 2011 | 21951598 |
| receptor activated c kinase is down-regulated in the male gonad of the marine bivalve mollusc mya arenaria exposed to tributyltin (tbt). | this study was aimed at investigating the molecular mechanisms by which tributyltin (tbt) impairs the reproductive processes in the marine bivalve mya arenaria. the suppression polymerase chain reaction subtractive hybridization (ssh) method was used to identify differentially expressed transcripts in the gonads of adult m. arenaria 72 h after a single injection of 160 ng tbt in the adductor muscle. subtractive cdna libraries comprising 322 clones were obtained. these clones were sequenced and c ... | 2007 | 17582516 |
| neuroendocrine disruption in mya arenaria clams during gametogenesis at sites under pollution stress. | this study examined the neuroendocrine status of clams on intertidal mud flats in the st. lawrence estuary and saguenay fjord areas during late gametogenesis. the impact of pollution was determined by a test battery of early stress markers (metallothioneins, heme levels, glutathione s-transferase activity), tissue damage (lipid peroxidation and dna damage) and morphologic characteristics (age, soft-tissue weight ratio and growth index). neuroendocrinal status was examined by tracking serotonin a ... | 2007 | 17321589 |
| a multispecies approach for monitoring persistent toxic substances in the gulf of gdańsk (baltic sea). | bivalve mussels are usually used for biomonitoring persistent toxic substances (pts) in coastal ecosystems. nevertheless, these organisms, which live attached on hard substrates, can be found along the sandy coasts only on human manufactured products. in this work different species collected in the gulf of gdańsk were compared to evaluate their suitability for monitoring pts pollution at a local scale. the clam mya arenaria seems to represent an excellent indicator of sediment pollution, mainly ... | 2008 | 17291585 |
| transmission studies of sarcoma in the soft-shell clam, mya arenaria. | transmission experiments with adult soft-shell clams (mya arenaria) demonstrated that clam sarcomas are transmissible with hemolymph from neoplastic animals but not with cell-free ultrafiltrates. non-neoplastic clams were injected with either hemolymph from neoplastic clams or a cell-free ultrafiltrate prepared from a subsample of the same hemolymph. injected clams were held in separate flow-through aquaria and examined for sarcomas by histocytology and histology. data at 17 weeks showed a 44% p ... | 1951 | 1520839 |
| assessment and molecular characterization of human intestinal parasites in bivalves from orchard beach, ny, usa. | bivalves have been shown to be carriers of the human intestinal parasites cryptosporidium parvum and toxoplasma gondii. the goal of this study is to determine the prevalence of protozoan parasites in mollusks of new york city using a polymerase chain reaction (pcr)-based assay. four species of mollusks, mya arenaria, geukensia demissa, crassostrea virginica, and mytilis edulis, were collected from orchard beach, ny in the fall of 2014, totaling 159 specimens. each individual mollusk was dissecte ... | 2016 | 27043590 |
| the capacity of the gunderboom in mamaroneck harbor on the reduction of e. coli and coliform bacteria from water and soft-shelled clams (mya arenaria). | harbor island park of mamaroneck harbor is one of the beaches that has been frequently closed to the public due to unsanitary swimming conditions. in 2002, a gunderboom bps (beach protection system) was reinstalled in harbor island park to lower bacterial levels in swimming areas. the first gunderboom had been destroyed by an oil spill several years before. the current gunderboom is an 800 foot curtain made of a treated polypropylene/polyester fabric and the company claims a 99.1% coliform reduc ... | 2007 | 17182384 |
| a p53-like protein from a freshwater mollusc lamellidens corrianus. | p53 is the most frequently mutated protein in human cancers and the accumulation of its high levels is a potential novel marker for malignancy. recently, its homologues such as p63 and p73 have been reported in human, mice and fish. environmentally induced alterations in p53 protein have been reported to contribute to pathogenesis of leukemia in soft-shell clam mya arenaria inhabiting polluted water, suggesting that p53 proteins can also be used as pollution markers. in the present study, the pr ... | 2006 | 17133770 |
| mortalin-based cytoplasmic sequestration of p53 in a nonmammalian cancer model. | in nature the soft shell clam mya arenaria develops a fatal neoplasm that shares molecular similarity with an unrelated group of human cancers. in leukemic clam hemocytes, wild-type p53 and mortalin proteins co-localize in the cytoplasm. a similar phenotype, characterized by cytoplasmic sequestration of wild-type p53 protein, has been observed in several human cancers (undifferentiated neuroblastoma, retinoblastoma, colorectal and hepatocellular carcinomas, and glioblastoma). in some of these ca ... | 2006 | 16651619 |
| butyltin accumulation in the marine clam mya arenaria: an evaluation of its suitability for monitoring butyltin pollution. | the use of mya arenaria as a new sensitive biomonitor of butyltins pollution in the oceanic system was investigated. field survey indicated that much higher levels of butyltin compounds were found in m. arenaria compared with the other species investigated. using mytilus edulis as a control organism, a 28 days exposure of tributyltin chloride (tbt) to m. arenaria for accumulation and subsequent 28 days breeding in clean seawater for elimination were conducted under laboratory conditions in order ... | 2006 | 16188291 |
| [biochemical research on the inactivation of 5-hydroxytryptamine at the level of the heart in the mollusca helix pomatia, buccinum undatum, venus mercenaria and mya arenaria]. | | 1965 | 4221676 |
| mitochondrial ageing of a polar and a temperate mud clam. | we investigated mitochondrial ageing in a temperate (mya arenaria) and an antarctic (laternula elliptica) mud clam, with similar lifestyle (benthic filter feeders) but different maximum life spans (mlsp), 13 and 36 years, respectively. the short-lived temperate m. arenaria showed a more pronounced decrease in mitochondrial function (respiration, respiratory control ratio, proton leak, membrane potential) with age than the long-lived antarctic l. elliptica. h2o2 generation rates at habitat temper ... | 2005 | 15811430 |
| chronological and physiological ageing in a polar and a temperate mud clam. | we investigated chronological and physiological ageing of two mud clams with regard to the "rate of living theory" (pearl, 1928) and the "free radical theory of ageing" (harman, 1956). the antarctic laternula elliptica (pholadomyoida) and the temperate mya arenaria (myoida) represent the same ecotype (benthic infaunal filter feeders), but differ in maximum life span, 36 and 13 years, respectively. l. elliptica has a two-fold lower standard metabolic rate than m. arenaria, but its life long energ ... | 2005 | 15811429 |
| development of a biomarker-based index for assessing the ecotoxic potential of aquatic sites. | the use of biochemical or physiological measurements as indicators of ecotoxicity is under constant development and has the advantage of delineating effects before the appearance of disease. however, these biomarkers are often part of a battery of tests, and it is difficult to integrate them together to gain an overall view of an organism's health. the aim of this study was to develop an index that could integrate the data derived from a battery of biomarkers for application to both spatial and ... | 2003 | 12944178 |
| delayed gametogenesis of mya arenaria in the saguenay fjord (canada): a consequence of endocrine disruptors? | the saguenay fjord located in canada on the north coast of the saint-lawrence estuary, is well known for its multiple contaminations following a linear distribution upstream to downstream. mya arenaria is well established in the fjord and potentially exposed to persistent sediment contamination as an endobenthic bivalve. from may to october 1997, clams energy storage and utilization in the gonad was shown to be closely linked with reproduction. wherever the sampling site location in the fjord, a ... | 2002 | 11976061 |
| oxidative stress and immunologic responses following a dietary exposure to pahs in mya arenaria. | the aim of this research was to investigate oxidative stress and immune responses following a dietary polycyclic aromatic hydrocarbon (pah) exposure in a marine bioindicator organism, the soft shell clam, mya arenaria. immune parameters in hemolymph (haemocyte number, efficiency of phagocytosis and haemocyte activity) and assessment of oxidative stress using catalase (cat) activity and levels of malondialdehyde (mda) performed on the digestive gland were estimated as biomarkers in clams fed in m ... | 2008 | 19055737 |
| mass culture and characterization of tumor cells from a naturally occurring invertebrate cancer model: applications for human and animal disease and environmental health. | on the northeastern coast of the united states and canada, mya arenaria, the soft shell clam, develops a diffuse, hemopoetic tumor (a fatal leukemia-like cancer) resulting from inactivation of p53-like family member proteins.these malignant cells provide a model for an unrelated set of human cancer cells that are also characterized by mortalin-based cytoplasmic sequestration of wild-type p53 tumor suppressor protein (mortalin is the mitochondrial hsp70 protein). here we describe methods for mass ... | 2009 | 19218489 |
| organochlorine residues in shellfish from maryland waters, 1976-1980. | shellfish samples, including the american oyster (craessostrea virginica), the soft shell clam (mya arenaria), the hard shell clam (mercenaria mercenaria) and the blue crab (callinectes sapidus), were taken from the maryland section of the chesapeake bay and its tributaries over a five year period (1976-80) and analyzed to determine residue levels of various organochlorine pesticides. qualitative and quantitative information was obtained for a variety of polychlorinated hydrocarbons. the purpose ... | 1984 | 6501793 |
| selection and evaluation of housekeeping genes for haemocytes of soft-shell clams (mya arenaria) challenged with vibrio splendidus. | gene expression studies have opened a tremendous field of investigation in biological research over the last decades. expression of genes is most frequently quantified by real time pcr (rt-qpcr), as this method has proven to be highly sensitive. one of the critical steps, however, in comparing transcription profiles is the availability of selected housekeeping genes. expression of these genes should be steadily stable across the conditions under study so that they provide a baseline for gene exp ... | 2008 | 18793642 |
| the toxicity of chlorothalonil to aquatic fauna and the impact of its operational use on a pond ecosystem. | chlorothalonil is a fungicide whose heavy use in eastern canada gives it the potential for significant aquatic contamination. laboratory bioassays and field treatments of a pond system were undertaken to determine the toxic effects of chlorothalonil on aquatic fauna. the 96-h lc50 of technical chlorothalonil for rainbow trout (oncorhynchus mykiss) was 76 micrograms/l and was not significantly different (p less than 0.05) from that of the formulated product (bravo 500). the 96-h lc50 of bravo 500 ... | 1991 | 1898106 |
| edna and specific primers for early detection of invasive species--a case study on the bivalve rangia cuneata, currently spreading in europe. | intense human activities facilitate the successful spread and establishment of non-indigenous aquatic organisms in marine and freshwater ecosystems. in some cases such intrusions result in noticeable and adverse changes in the recipient environments. in the baltic sea, the discovery and rapid initial spread of the north american wedge clam rangia cuneata represents a new wave of invasion which may trigger unpredictable changes of the local benthic communities. in this study we present a species- ... | 2015 | 26453004 |
| Liquid chromatography post-column oxidation (PCOX) method for the determination of paralytic shellfish toxins in mussels, clams, oysters, and scallops: collaborative study. | Sixteen laboratories participated in a collaborative study to evaluate method performance parameters of a liquid chromatographic method of analysis for paralytic shellfish toxins (PST) in blue mussels (Mytilus edulis), soft shell clams (Mya arenaria), sea scallops (Placopectin magellanicus), and American oysters (Crassostrea virginicus). The specific analogs tested included saxitoxin, neosaxitoxin, gonyautoxins-1 to -5, decarbamoyl-gonyautoxins-2 and -3, decarbamoyl-saxitoxin, and N-sulfocarbamo ... | 2011 | 21919349 |
| selected enzyme activities in mya arenaria hemolymph. | 1. the activities of lysozyme, acid and alkaline phosphatases, beta-glucuronidase, amylase, lipase, glutamate-oxalacetate transaminase, and glutamate-pyruvate transaminase in the whole hemolymph and 4000 g pellets and supernatants of mya arenaria were determined. 2. all of these enzymes, except for amylase, occurred in whole hemolymph as well as in the 4000 g pellet and supernatant. 3. based on earlier observations, these enzymes are believed to be of cellular origin within hemolymph cells. 4. i ... | 1999 | 95692 |
| ozone detoxification of paralytic shellfish poison in the softshell clam (mya arenaria). | | 2004 | 524392 |
| structural changes in molluscan community over a 15-year period before and after the 2011 great east japan earthquake and subsequent tsunami around matsushima bay, miyagi prefecture, northeastern japan. | we examined structural changes in the molluscan community for ten years (2001-2010) before and five years (2011-2015) after the 2011 great east japan earthquake and subsequent tsunami around matsushima bay, miyagi prefecture, northeastern japan. before the earthquake and tsunami, ruditapes philippinarum, macoma incongrua, pillucina pisidium, and batillaria cumingii were dominant, and an alien predator laguncula pulchella appeared in 2002 and increased in number. after the tsunami, r. philippinar ... | 2016 | 27936182 |
| seasonal aspects of sarcomatous neoplasia in mya arenaria (soft-shell clam) from long island sound. | | 2009 | 3693943 |
| immunocompetence of bivalve hemocytes as evaluated by a miniaturized phagocytosis assay. | immune function in bivalves can be adversely affected by long-term exposure to environmental contaminants. investigating alterations in immunity can therefore yield relevant information about the relationship between exposure to environmental contaminants and susceptibility to infectious diseases. we have developed a rapid, cost-effective, and miniaturized immunocompetence assay to evaluate the phagocytic activity, viability, and concentration of hemocytes in freshwater and marine bivalves. prel ... | 2002 | 12112624 |
| selective initiation and transmission of disseminated neoplasia in the soft shell clam mya arenaria dependent on natural disease prevalence and animal size. | disseminated neoplasia, a diffuse tumor of the hemolymph system, is one of the six most destructive diseases among bivalve mollusk populations, characterized by the development of abnormal, rounded blood cells that actively proliferate. though the specific etiology of disseminated neoplasia in mya arenaria remains undetermined, the involvement of viral pathogens and/or environmental pollutants has been suggested and considered. the current study used 5-bromodeoxyuridine (brdu) known to induce th ... | 2013 | 23079141 |
| preliminary investigation of a sensitive biomarker of organotin pollution in chinese coastal aquatic environment and marine organisms. | in nine batches of sea bivalves collected from chinese coastal cities during the year of 2000 to 2002, a special sample named mya arenaria was found to have strong ability of butyltin accumulation compared with the other sampled bivalves in the corresponding batches. tributyltin compound was the predominant pollutant with the detection rate high up to 100%. special high levels of g sn/g were detected in some mya arenaria samples. the results obtained showed that mya arenaria was potentially a bi ... | 2003 | 12826407 |
| differential in vivo response of soft-shell clam hemocytes against two strains of vibrio splendidus: changes in cell structure, numbers and adherence. | host-pathogen interaction models in aquatic species are useful tools for understanding the pathogenicity of diseases in cultured and wild populations. in this study we report the differential in vivo response of soft-shell clam (mya arenaria) hemocytes against two strains of vibrio splendidus. responses were measured 24h after injecting into the posterior adductor muscle either an endemic wild-type strain (7shrw) or a strain associated with oyster mortalities (lgp32-gfp). changes in hemocyte str ... | 2009 | 19576219 |
| cristispira in north american shellfish. a note on a spirillum found in oysters. | ten varieties of north american shellfish were examined for the occurrence of cristispira in their styles. a cristispira was found in various numbers in ostrea virginiana, venus mercenaria, and modiola modiolus, but none in ensis americana, mya arenaria, mactra solidissima, pecten irradians, mytilus edulis, fulgur canaliculatus, or nassa obsoleta. of 298 oysters, only 128 showed the crystalline styles, in which cristispiras were present in 99. active cristispiras were found in 59 styles only and ... | 1921 | 19868559 |
| changes induced by two strains of vibrio splendidus in haemocyte subpopulations of mya arenaria, detected by flow cytometry with lysotracker. | flow-cytometric characterisation of bivalve haemocytes is usually performed by light-scatter profiles based on size and complexity of the cells. additional means of characterisation such as specific fluorescent dyes are not commonly used to discriminate cell subpopulations in challenged and unchallenged haemocytes. in the present study, we characterise the changes in haemocyte subpopulations of soft-shell clam mya arenaria induced by in vivo challenge with 2 strains of vibrio splendidus by using ... | 2009 | 20066960 |
| exposure to excess dissolved iron in vivo affects oxidative status in the bivalve mya arenaria. | the effect of in vivo fe exposure on the oxidative metabolism of the bivalve myaarenaria was studied. fe was supplemented in natural seawater and resulted in a significant increase in the total fe content in the bivalve digestive gland (dg) between 9 to 17days of exposure. mortality of treated animals increased drastically after day 18. oxidative stress conditions were characterized in dg through assessment of the generation of reactive oxygen species (ros) and ascorbyl radical (a) content. both ... | 2010 | 20398794 |
| identification and expression of immune-related genes in hemocytes of soft-shell clams, mya arenaria, challenged with vibrio splendidus. | although the mollusc immune system has been studied at the cellular level, the response to pathogens at gene expression level has not been thoroughly investigated. this study aimed to investigate the early molecular response of hemocytes of soft-shell clams, mya arenaria, to vibrio splendidus strain lgp32 by identification of transcripts involved in immune defense. the suppression subtractive hybridization (ssh) was used to selectively identify differentially expressed genes in hemocytes exposed ... | 2010 | 20600957 |
| physiological effects of temperature and a herbicide mixture on the soft-shell clam mya arenaria (mollusca, bivalvia). | the aim of the current study was to investigate effects of temperature and a mixture of herbicides on the physiological status of the bivalve mya arenaria. bivalves acclimated to two temperatures (7 and 18°c) were exposed for 28 d to 0.01 mg/l of a pesticide formulation containing dichlorophenoxyacetic acid (2,4-d), 2-(2-methyl-4-chlorophenoxy) propionic acid (mecoprop), and 3,6-dichloro-2-methoxybenzoic acid (dicamba). at days 7, 14, and 28, mortality, immune parameters (hemocyte number, phagoc ... | 2011 | 20853449 |
| phagocytic activity of marine and freshwater bivalves: in vitro exposure of hemocytes to metals (ag, cd, hg and zn). | we measured non-specific immune function of various bivalves from marine (cyrtodaria siliqua, mactromeris polynyma, mesosdesma arctatum, mya arenaria, mya truncata, mytilus edulis, serripes groenlandicus, siliqua costata) and freshwater environments (dreissena polymorpha and elliptio complanata). we used flow cytometry to quantify the phagocytosis of fluorescent microspheres by hemocytes exposed in vitro to increasing levels of various metal compounds (agno(3), cdcl(2), ch(3)hgcl, hgcl(2) and zn ... | 2002 | 12007874 |
| p53 superfamily proteins in marine bivalve cancer and stress biology. | the human p53 tumour suppressor protein is inactivated in many cancers and is also a major player in apoptotic responses to cellular stress. the p53 protein and the two other members of this protein family (p63, p73) are encoded by distinct genes and their functions have been extensively documented for humans and some other vertebrates. the structure and relative expression levels for members of the p53 superfamily have also been reported for most major invertebrate taxa. the functions of homolo ... | 2011 | 21724017 |
| an aryl hydrocarbon receptor (ahr) homologue from the soft-shell clam, mya arenaria: evidence that invertebrate ahr homologues lack 2,3,7,8-tetrachlorodibenzo-p-dioxin and beta-naphthoflavone binding. | the aryl hydrocarbon receptor (ahr) mediates numerous toxic effects following exposure of vertebrate animals to certain aromatic environmental contaminants, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (tcdd). to investigate possible effects of tcdd on invertebrates, a cdna encoding an ahr homologue was cloned from the soft-shell clam, mya arenaria. the predicted amino acid sequence contains regions characteristic of vertebrate ahrs: basic helix-loop-helix (bhlh) and per-arnt-sim (pas) domains ... | 2001 | 11707340 |
| acute toxicities of cd2+, cr+6 hg2+, ni2+ and zn2+ to estuarine macrofauna. | static acute toxicity bioassays were conducted at 20 degrees c and 20 o/33 salinity with cdcl2-2 1/2 h20, k2cro4, hgcl2, nicl2-6h2o, and zncl2 using adults of starfish, asterias forbesi; sandworm, nereis virens; hermit crab, pagurus longicarpus; softshell clam, mya arenaria; mudsnail, nassarius obsoletus; and mummichog, fundulus heteroclitus, a fish. concentrations (mg/l metal) fatal to 50% of the organisms in 168 hr ranged from 0.004 (clam) to 0.8 (mummichog) for mercury; 0.7 (clam, worm, crab ... | 1977 | 901010 |
| cercaria myae sp. nov., a fork-tailed larva from the marine bivalve, mya arenaria. | | 1952 | 14946631 |
| galectin cvgal2 from the eastern oyster (crassostrea virginica) displays unique specificity for abh blood group oligosaccharides and differentially recognizes sympatric perkinsus species. | galectins are highly conserved lectins that are key to multiple biological functions, including pathogen recognition and regulation of immune responses. we previously reported that cvgal1, a galectin expressed in phagocytic cells (hemocytes) of the eastern oyster (crassostrea virginica), is hijacked by the parasite perkinsus marinus to enter the host, where it causes systemic infection and death. screening of an oyster hemocyte cdna library revealed a novel galectin, which we designated cvgal2, ... | 2015 | 26158802 |
| attraction of predatorily naive postlarval lobsters to extracts of metabolites of common prey:mytilus edulis, mya arenaria, cancer irroratus, andasterias vulgaris. | postlarval lobsters (4th-7th stage) exclusively fed frozen brine shrimp (artemia saline) were assayed for food-search response to extracts and metabolites from four common prey: soft clams (mya arenaria), blue mussels (mytilus edulis), rock crabs (cancer irroratus), and sea stars (asterias vulgaris). concentrations of soluble primary amines, protein, and ammonia in prey tissues and metabolites were determined. no significant responses were observed for any prey metabolites diluted to 1 and 10%, ... | 1987 | 24302143 |
| ambient fauna impairs parasite transmission in a marine parasite-host system. | to understand possible factors controlling transmission of trematode larvae between first and second intermediate hosts we examined the impact of ambient fauna on parasite transmission in a marine intertidal parasite-host association. cockle hosts (cerastoderma edule) kept together with selected co-occurring macrozoobenthic species in mesocosms acquired a lower parasite load compared to cockles kept alone, when targeted by cercariae of the trematode himasthla elongata. the reduction of parasite ... | 2008 | 18561867 |
| widespread transmission of independent cancer lineages within multiple bivalve species. | most cancers arise from oncogenic changes in the genomes of somatic cells, and while the cells may migrate by metastasis, they remain within that single individual. natural transmission of cancer cells from one individual to another has been observed in two distinct cases in mammals (tasmanian devils and dogs), but these are generally considered to be rare exceptions in nature. the discovery of transmissible cancer in soft-shell clams (mya arenaria) suggested that this phenomenon might be more w ... | 2016 | 27338791 |
| disseminated neoplasia in the soft-shell clam mya arenaria: membrane lipid composition and functional parameters of circulating cells. | in a previous study we compared lipid composition and functional parameters of circulating cells from cerastoderma edule affected or not by disseminated neoplasia (neoplastic cells vs hemocytes) (le grand et al. chem phys lipids 167:9-20 2013). neoplastic cells presented morpho-functional modifications concomitant to striking membrane lipid alterations: the proportion of particular plasmalogen molecular species was drastically decreased. we wanted to test whether this pattern was representative ... | 2014 | 24934587 |
| vasa expression suggests shared germ line dynamics in bivalve molluscs. | germ line segregation can occur during embryogenesis or after embryogenesis completion, with multipotent cells able to give rise to both germ and somatic cells in the developing juvenile or even in adulthood. these undifferentiated cells, in some animals, are self-renewing stem cells. in all these cell lineages, the same set of genes, among which vasa, appears to be expressed. we traced vasa expression during the peculiar gonad rebuilding of bivalves to verify its presence from undifferentiated ... | 2017 | 28386635 |
| in vitro interactions between several species of harmful algae and haemocytes of bivalve molluscs. | harmful algal blooms (habs) can have both lethal and sublethal impacts on shellfish. to understand the possible roles of haemocytes in bivalve immune responses to habs and how the algae are affected by these cells (haemocytes), in vitro tests between cultured harmful algal species and haemocytes of the northern quahog (= hard clam) mercenaria mercenaria, the soft-shell clam mya arenaria, the eastern and pacific oysters crassostrea virginica and crassostrea gigas and the manila clam ruditapes phi ... | 2011 | 21340660 |
| laboratory investigations of the effects of predator sex and size on prey selection by the asian crab, hemigrapsus sanguineus. | laboratory studies have shown that the nonindigenous asian shore crab, hemigrapsus sanguineus, readily consumes three species of commercial bivalves: blue mussels, mytilus edulis, soft-shell clams, mya arenaria, and oysters, crassostrea virginica. although crabs can eat bivalves of a wide size range, they preferred the smaller prey (</=10 mm sl). prey critical size limits exist for m. edulis and c. virginica, but not m. arenaria, possibly because of differences in shell characteristics among the ... | 2001 | 11445087 |
| hemocyte-derived reactive oxygen intermediate production in four bivalve mollusks. | luminol-dependent chemiluminescence (ldcl) and nitroblue tetrazolium (nbt) reduction assays have been used to measure reactive oxygen intermediate (roi) production by oyster (crassostrea virginica) hemocytes, as well as roi modulation caused by disease or exposure to environmental toxicants. however, roi responses measured by these tests apparently vary considerably among other bivalve species. in all species tested, unstimulated hemocytes produced small quantities of rois. in c. virginica and g ... | 2011 | 8082818 |
| elapid alpha-toxins have no effect on the cholinergic responses of bivalve myocardia. | elapid alpha-toxins (alpha-bungarotoxin, alpha-cobratoxin and crude bungarus caeruleus venom) do not affect the myocardial nicotinic ach receptors of the following bivalve molluscs: mercenaria mercenaria, chione cancellata, mya arenaria, mytilus edulis, rangia cuneata and crassostrea virginica. | 1978 | 729727 |