| quadrupole ion storage tandem mass spectrometry and high-resolution mass spectrometry: complementary application in the measurement of 2,3,7,8-chlorine substituted dibenzo-p-dioxins and dibenzofurans in us foods. | the us food and drug administration has simultaneously utilized both high-resolution mass spectrometry (hrms) and quadrupole ion storage tandem mass spectrometry (qistms) in the measurement of polychlorinated dibenzo-p-dioxins/dibenzofurans (pcdd/fs) in 147 food samples collected in 1998 and 1999 in the us. in 1998, 20 egg samples, six scallop, 10 blue crab, eight american lobster, 10 pollack, 15 striped bass, five rockfish, 10 crawfish, seven aqua-cultured and 13 wild-caught salmon, along with ... | 2001 | 11372820 |
| purification of vitellin from grass shrimp palaemonetes pugio, generation of monoclonal antibodies, and validation for the detection of lipovitellin in crustacea. | much effort has been put into developing vitellogenin antibodies against a wide variety of aquatic vertebrate species to study potential estrogen or anti-estrogen endocrine disrupters. little work has been done on endocrine disruption in aquatic invertebrates. although some antibodies have been produced against blue crab and penaeid shrimp lipovitellin, they have only poor cross-reactivity with the important estuarine grass shrimp, palaemonetes pugio. vitellin was purified from eggs, monoclonal ... | 2000 | 11083030 |
| methodological and biological aspects to be considered in acetylcholinesterase reactivation assays using 2-pam. | kinetic and toxicological characteristics of fish (odontesthes argentinensis) and crab (callinectes sapidus) cholinesterases as well as methodological conditions to perform reactivation assays using pyridine 2-aldoxime (2-pam) were established. according to kinetic and eserine sensitivity data, both cholinesterases can be considered as acetylcholinesterases. the concentration of eserine that inhibited 50% of enzyme activity (ic(50)) was estimated as 15.9x10(-8) and 4.6x10(-8) m for crab and fish ... | 2000 | 11137467 |
| epizootiology of the parasitic dinoflagellate hematodinium sp. in the american blue crab callinectes sapidus. | hematodinium sp. is a parasitic dinoflagellate that infects and kills blue crabs callinectes sapidus. periodic outbreaks of dinoflagellate infections with subsequent high host mortalities prompted a study of the epizootiology and distribution of the crab pathogen. hemolymph samples from over 13000 crabs were assessed for infections over 8 yr. moderate to high prevalences were found at several locations along the atlantic and gulf coasts of the united states. in the coastal bays of maryland and v ... | 2000 | 11145454 |
| novel subcellular and molecular tools to study ca(2+) transport mechanisms during the elusive moulting stages of crustaceans: flow cytometry and polyclonal antibodies. | our understanding of calcium homeostasis during the crustacean moulting cycle derives from research on intermoult animals that has been extrapolated to other stages. in terms of transepithelial ca(2+) flux, the more interesting stages are those surrounding ecdysis since crustaceans experience a sizeable negative calcium balance in immediate premoult and a significant positive calcium balance in immediate postmoult. these stages are elusive in the sense that larger species such as lobsters are ra ... | 2001 | 11171419 |
| factors influencing planktonic, post-settlement dispersal of early juvenile blue crabs (callinectes sapidus rathbun). | an emerging body of literature points to post-settlement, planktonic dispersal as a key determinant of distribution and abundance patterns of aquatic organisms, yet little is known about mechanisms inducing such dispersal. recent evidence suggests that early juvenile blue crabs (callinectes sapidus rathbun) may use planktonic emigration as a means of post-settlement dispersal. the goal of this study was to identify mechanisms inducing post-settlement, planktonic dispersal of early juvenile blue ... | 2001 | 11245875 |
| effects of periodic hypoxia on mortality, feeding and predation in an estuarine epifaunal community. | the york river estuary, a tributary of the chesapeake bay, usa, experiences periodic low oxygen stress (hypoxia), yet epifaunal species form dense communities there. we studied hypoxia tolerance of common epifaunal species in the york river by exposing sessile and mobile epifauna to high and low oxygen concentrations in laboratory aquaria. mortality in hypoxia varied among species, ranging from 0% to 100%, with trends of decreased tolerance by mobile species relative to sessile species. while mo ... | 2001 | 11278013 |
| carbonic anhydrase isozyme distribution and characterization in metabolic fiber types of the dorsal levator muscle of the blue crab, callinectes sapidus. | carbonic anhydrase (ca) distribution and characterization were examined in white and light pink fibers of the dorsal levator muscle of the blue crab. white fibers were structurally and metabolically characterized as fast twitch glycolytic, while the light pink fibers were fast oxidative. all subcellular fractions of both fiber types had significant levels of ca activity; cytoplasmic and microsomal activity was significantly higher in light pink vs white fibers. cytoplasmic ca from both fiber typ ... | 2001 | 11479903 |
| flux of heavy metal accumulation in various organs of the intertidal marine blue crab, portunus pelagicus (l.) from the kuwait coast after the gulf war. | the metal levels of arsenic, chromium, copper, lead, magnesium, manganese, selenium, vanadium, and zinc concentrations were determined in various body organs, viz., hepatopancreas, gills, gonad, gastric stomach, and muscle of the blue crab, portunus pelagicus (crustacea: decapoda) to assess the bioaccumulation of metals associated with petroleum input a decade after the 1991 gulf war oil spillage. sample solutions prepared were analyzed using an atomic absorption spectrophotometry. high concentr ... | 2001 | 11686643 |
| cardiovascular system of the blue crab callinectes sapidus. | the circulatory system of adult blue crabs, callinectes sapidus, was mapped by either injecting barium sulfate into intact animals followed by radiography or by resin corrosion casts (batsons monomer). seven arteries arise from the heart. the anterior aorta exits from the anterior dorsal surface of the heart and gives rise to the optic arteries; these arteries supply hemolymph to the supraesophageal ganglion and eyestalks. the paired anterolateral arteries also exit from the anterior dorsal surf ... | 2002 | 11746465 |
| expression of crustacean (callinectes sapidus) molt-inhibiting hormone in insect cells using recombinant baculovirus. | molt-inhibiting hormone (mih) negatively regulates the synthesis of ecdysteroid molting hormones by crustacean y-organs. we report here the expression of blue crab (callinectes sapidus) mih in insect cells using recombinant baculovirus. insect sf9 cells were transfected with recombinant baculovirus containing a dna insert encoding the c. sapidus mih prohormone (signal sequence plus mature hormone). the construct was designed to yield a mature, fully processed recombinant mih (recmih). several ba ... | 2002 | 11754021 |
| cloning and sequencing of cdnas encoding for a novel copper-specific metallothionein and two cadmium-inducible metallothioneins from the blue crab callinectes sapidus. | metallothioneins (mts) are cysteine-rich metal-binding proteins found in micro-organisms, plants and all invertebrate and vertebrate animals. unicellular eukaryotes such as yeast have a copper-mt whose synthesis is induced by a copper-activated transcription factor. most higher organisms have two major cadmium/zinc mt isoforms, whose synthesis is controlled by a zinc-activated transcription factor. the blue crab, callinectes sapidus, has two cadmium-inducible isoforms, cdmt-i and cdmt-ii, and a ... | 2000 | 11790353 |
| role of a copper-specific metallothionein of the blue crab, callinectes sapidus, in copper metabolism associated with degradation and synthesis of hemocyanin. | we have identified three mt encoding genes in the blue crab: mt-i, inducible by cadmium, zinc and copper; mt-ii, inducible by cadmium and zinc; and mt-iii, inducible by copper only [syring et al., comp. biochem. physiol. c, 125 (2000) 325-332]. to examine the role of the cumt-i and cumt-iii isoforms in copper metabolism associated with the synthesis and degradation of the oxygen-binding copper protein, hemocyanin, we (1) cloned and sequenced hemocyanin cdna, (2) examined interaction of the cumts ... | 2002 | 11803044 |
| mercury accumulation and flux across the gills and the intestine of the blue crab (callinectes sapidus). | this paper details the results of perfusion experiments examining the accumulation of inorganic and methylmercury (hg and mmhg) into the gill and intestine tissue of the blue crab, callinectes sapidus. additionally, the flux across the tissue to an internal medium, representative of crab tissue or haemolymph, during the perfusion was also measured. the accumulation and transfer processes were studied for each form by exposing the organs to a wide range of hg and mmhg water concentrations, as wel ... | 2002 | 11856578 |
| effect of ligands and other metals on the uptake of mercury and methylmercury across the gills and the intestine of the blue crab (callinectes sapidus). | using the perfusion method, we compared the accumulation and flux of inorganic mercury (hg) and methylmercury (ch(3)hg) across the gills and intestine of the blue crab, callinectes sapidus. the accumulation and transfer processes were studied for each form by exposing the organs in the presence of specific ligands and other metals. while binding of hg and ch(3)hg to organic ligands reduced the rate of uptake in most instances, the differences in accumulation could not be explained only in terms ... | 2002 | 11879786 |
| the genomic organization of the open reading frame of the red pigment concentrating hormone gene in the blue crab callinectes sapidus. | the open reading frame (orf) of the gene for the precursor of the octapeptide red pigment concentrating hormone (rpch) from the blue crab callinectes sapidus was cloned by pcr with oligonucleotides targeted to the initiation and the end of the translation coding sequences. a 272 bp intron was characterized between nucleotides 343 and 344 of the reported cdna, present in the region coding for the last amino acids of the precursor related peptide of rpch. the intron genomic structure here describe ... | 2002 | 11897398 |
| toxicity of methyl tert-butyl ether to marine organisms: ambient water quality criteria calculation. | in response to increasing concerns over the detection of methyl tert-butyl ether (mtbe) in groundwater and surface water and its potential effects in aquatic ecosystems, industry and the united states environmental protection agency (usepa) began to collaborate in 1997 to develop aquatic toxicity databases sufficient to derive ambient water quality criteria for mtbe consistent with usepa requirements. acute toxicity data for seven marine species, chronic toxicity data for an invertebrate, and pl ... | 2002 | 11996128 |
| osmotic effects on arginine kinase function in living muscle of the blue crab callinectes sapidus. | flux was examined through the reaction catalyzed by arginine kinase in intact blue crab (callinectes sapidus) muscle during simulated changes in salinity. isolated dark levator muscles from the swimming leg were superfused with a saline solution that had an osmolarity equivalent to that of the hemolymph under different salinity regimes. animals were acclimated for 7 days to a salinity of 5, 17 or 35 per thousand, which corresponds to a hemolymph osmolarity of 640, 720 or 960 mosmoll(-1), respect ... | 2002 | 12042336 |
| trophic accumulation and depuration of mercury by blue crabs (callinectes sapidus) and pink shrimp (penaeus duorarum). | mercury concentrations in blue crabs (callinectes sapidus) collected from an area of mercury-contaminated sediments in lavaca bay, tx, usa, are more than an order of magnitude greater than concentrations in penaeid shrimp from the same area. laboratory feeding experiments using mercury-contaminated fish as food showed that both blue crabs and pink shrimp (penaeus duorarum) could accumulate mercury concentrations comparable to those in their food in 28 days. calculated mercury assimilation effici ... | 2000 | 11285721 |
| glycosidase activity in the post-ecdysial cuticle of the blue crab, callinectes sapidus. | we have previously demonstrated a marked change in sugar moieties of glycoproteins of the cuticle of the blue crab, callinectes sapidus, between 0.5 and 3 h post-ecdysis. the present study has identified a glycosidase that appears in the cuticle during the early post-ecdysial hours. the enzyme has affinities for p-nitrophenyl derivatives of both n-acetylglucosamine and n-acetylgalactosamine. both activities are competitively inhibited by chitobiose, suggesting that the enzyme could be a n-acetyl ... | 2001 | 11290450 |
| a trophic cascade regulates salt marsh primary production. | nutrient supply is widely thought to regulate primary production of many ecosystems including salt marshes. however, experimental manipulation of the dominant marsh grazer (the periwinkle, littoraria irrorata) and its consumers (e.g., blue crabs, callinectes sapidus, terrapins, malaclemys terrapin) demonstrates plant biomass and production are largely controlled by grazers and their predators. periwinkle grazing can convert one of the most productive grasslands in the world into a barren mudflat ... | 2002 | 12149475 |
| early carbonic anhydrase induction in the gills of the blue crab, callinectes sapidus, during low salinity acclimation is independent of ornithine decarboxylase activity. | carbonic anhydrase (ca) induction in the gills of the euryhaline blue crab, callinectes sapidus, was measured in response to lowered environmental salinity. simultaneous measurements of ornithine decarboxylase (odc) activity were made in gills and nonbranchial tissues to determine whether odc activity and the resultant synthesis of polyamines played a role in the initiation and regulation of ca induction. ca induction in the seventh gill pair (g7) was proportional to the decrease in ambient sali ... | 2001 | 11351322 |
| behavioral observations and computer simulations of blue crab movement to a chemical source in a controlled turbulent flow. | the behavior of crabs tracking odor in turbulent chemical plumes was compared to the performance of computer simulations of search behavior operating in similar chemical signal environments. the movement of blue crabs (callinectes sapidus) towards a source of food odor was studied in controlled flow conditions in a flume. the evolving chemical stimulus field of a similar chemical source in an equivalent flow environment was captured by recording concentration patterns of a fluorescent tracer. hy ... | 2002 | 12324548 |
| orientation of the fiddler crab, uca cumulanta: responses to chemical and visual cues. | behavioral responses of the fiddler crab uca cumulanta to flat geometric shapes mimicking natural objects were measured in a circular arena by using zonal recovery as a behavioral measurement. crabs were tested either in presence or absence of odors from two common predator species, the blue crab callinectes sapidus, and the pufferfish sphoeroides testudineus. the study tested the hypothesis that u. cumulanta have different behavioral responses to visual cues in the presence of chemical cues ass ... | 2002 | 12449506 |
| fluid mechanics produces conflicting, constraints during olfactory navigation of blue crabs, callinectes sapidus. | foraging blue crabs must respond to fluid forces imposed on their body while acquiring useful chemical signals from turbulent odor plumes. this study examines how blue crabs manage these simultaneous demands. the drag force, and hence the cost of locomotion, experienced by blue crabs is shown to be a function of the body orientation angle relative to the flow. rather than adopting a fixed orientation that minimizes the drag, blue crabs decrease their relative angle (increase drag) when odor is p ... | 2003 | 12456707 |
| inhibition of carbonic anhydrase in the gills of two euryhaline crabs, callinectes sapidus and carcinus maenas, by heavy metals. | two subcellular fractions of gill tissue, cytoplasm and basolateral membranes, from two species of euryhaline decapod crustaceans, callinectes sapidus and carcinus maenas, acclimated to low salinity, were isolated via differential centrifugation. carbonic anhydrase activity from both fractions was titrated against a variety of heavy metals in vitro. the metals ag(+), cd(2+), cu(2+) and zn(+) showed inhibitory action against the enzyme. ki values for these metals against cytoplasmic ca from c. sa ... | 2002 | 12458188 |
| fish tissue quality in the lower mississippi river and health risks from fish consumption. | between 1990 and 1994, samples of three shellfish species (i.e. blue crab, callinectes sapidus;crayfish, procambarus acutis; and river shrimp, macrobrachium ohionii) and 16 fish species and were collected at six sites along the lower mississippi river by the louisiana department of environmental quality, office of water resources in coordination with the us environmental protection agency. the fish species included: bigmouth buffalo (ictiobus cyanellus); blue catfish (ictalurus furcatus); carp ( ... | 2003 | 12526903 |
| synthesis of a high-density lipoprotein in the developing blue crab (callinectes sapidus). | an important lipoprotein in the hemolymph of crustaceans is lpi. it transports lipid to peripheral tissues and also has a role in crustacean immune recognition. we employed a monoclonal antibody specific for the lpi peptide to demonstrate by elisa, western blot and immunohistochemistry the appearance of lpi during development of callinectes sapidus, the blue crab. lpi was first found in stage 5 embryos and appeared to be synthesized by lateral basophilic cuboidal cells that demonstrated cytoplas ... | 2003 | 12588744 |
| formation of the arthrodial membrane in the blue crab, callinectes sapidus. | in this study the pattern of arthrodial membrane deposition in callinectes sapidus was determined by histological and ultrastructural examination of tissues from the carpus joint of the cheliped collected during premolt, ecdysis, postmolt, and intermolt. apolysis in the arthrodial membrane occurs at stage d(0) and is synchronous with apolysis of the calcified cuticle. epicuticle formation begins at early stage d(1) and is completed in late stage d(1). procuticle deposition starts at d(2) and con ... | 2003 | 12655609 |
| gill (na+,k+)-atpase from the blue crab callinectes danae: modulation of k+-phosphatase activity by potassium and ammonium ions. | the kinetic properties of a microsomal gill (na(+),k(+))-atpase from the blue crab callinectes danae were analyzed using the substrate p-nitrophenylphosphate. the (na(+),k(+))-atpase hydrolyzed pnpp obeying cooperative kinetics (n=1.5) at a rate of v=125.4+/-7.5 u mg(-1) with k(0.5)=1.2+/-0.1 mmol l(-1); stimulation by potassium (v=121.0+/-6.1 u mg(-1); k(0.5)=2.1+/-0.1 mmol l(-1)) and magnesium ions (v=125.3+/-6.3 u mg(-1); k(0.5)=1.0+/-0.1 mmol l(-1)) was cooperative. ammonium ions also stimul ... | 2003 | 12670789 |
| scaling of gill metabolic potential as a function of salinity in the euryhaline crab, callinectes sapidus rathbun. | the body-size scaling pattern of enzymes that are important in energy metabolism was examined in gills of the blue crab as a function of acclimation salinity. we hypothesized that the higher surface-area-to-volume ratio of small crabs would impose a greater metabolic cost for hyperosmoregulation, leading to an increase in the capacity for atp production in gills. postmetamorphic crabs spanning a 2,500-fold range in body mass were examined following a 7-d exposure to a salinity of 35, 17, or 5 pp ... | 2003 | 12695991 |
| the presence and antimicrobial susceptibilities of human-pathogen vibrio spp. isolated from blue crab (callinectes sapidus) in belek tourism coast, turkey. | monitoring of vibrio species by blue crabs (callinectes sapidus) was carried out during the winter period in a selected area of the belek, antalya gulf. eighty-three blue crabs were examined for vibrio species. v. alginolyticus (30.1%), v. fluvialis (10.8%), v. damsela (9.6%), v. harveyi (3.6%), v. metschnikovii (3.6%) and v. vulnificus (2.4%) were isolated. v. vulnificus was the highest concentration (5 x 10(8) vibrio ml(-1)) although it was only 2.4% isolated from blue crabs. the strains of di ... | 2003 | 12745351 |
| replacement of a cytosolic copper/zinc superoxide dismutase by a novel cytosolic manganese superoxide dismutase in crustaceans that use copper (haemocyanin) for oxygen transport. | the blue crab, callinectes sapidus, which uses the copper-dependent protein haemocyanin for oxygen transport, lacks the ubiquitous cytosolic copper-dependent enzyme copper/zinc superoxide dismutase (cu,znsod) as evidenced by undetectable levels of cu,znsod activity, protein and mrna in the hepatopancreas (the site of haemocyanin synthesis) and gills. instead, the crab has an unusual cytosolic manganese sod (cytmnsod), which is retained in the cytosol, because it lacks a mitochondrial transit pep ... | 2003 | 12769817 |
| coastal seas as a context for science teaching: a lesson from chesapeake bay. | lessons that employ authentic environmental data can enhance the ability of students to understand fundamental science concepts. this differs from traditional "environmental education" in that school curricula need not set aside time for educators to teach only environmental topics. rather, the "environment" is used to advance student learning in science and technology. the success of this approach depends on programs that encourage scientists to communicate more effectively with teachers at all ... | 2003 | 12787628 |
| mitochondrial distribution and glycogen dynamics suggest diffusion constraints in muscle fibers of the blue crab, callinectes sapidus. | the scaling of mitochondrial distribution, citrate synthase activity, and post-contractile glycogen recovery was examined in muscle fibers of the blue crab, callinectes sapidus. the fast-twitch muscle fibers of c. sapidus can reach extremely large dimensions, which may impose constraints on aerobic metabolic processes. however, muscle cells from small crabs are not giant, meaning that during development muscle fibers cross and greatly exceed the surface area to volume (sav) and diffusion thresho ... | 2003 | 12911109 |
| [study of the endoplasmic reticulum in muscular fibers of the blue crab by electron microscopy]. | | 1960 | 14414628 |
| sequencing and amplified restriction fragment length polymorphism analysis of ribonucleotide reductase large subunit gene of the white spot syndrome virus in blue crab (callinectes sapidus) from american coastal waters. | in the present study, the existence of white spot syndrome virus (wssv) in blue crab (callinectes sapidus) collected from 3 different american coastal waters (new york, new jersey, and texas) was confirmed by 2-step diagnostic polymerase chain reaction and in situ hybridization analysis. when geographic isolates were also compared using a gene that encodes the wssv ribonucleotide reductase large subunit rr1 (wssv rr1), a c(1661)-to-t point mutation was found in the new jersey wssv isolated. this ... | 2001 | 14961379 |
| evaluation of a florida coastal golf complex as a local and watershed source of bioavailable contaminants. | contaminant fate in coastal areas impacted by golf course runoff is not well understood. this report summarizes trace metal, pesticide and pcb residues for colonized periphyton, ruppia maritima (widgeon grass), callinectes sapidus rathbun (blue crabs) and crassostrea virginica gemlin (eastern oyster) collected from areas adjacent to a florida golf course complex which receive runoff containing reclaimed municipal wastewater. concentrations of 19 chlorinated pesticides and 18 pcb congeners were u ... | 2004 | 14972577 |
| structural basis for salinity-induced alteration in oxygen binding by haemocyanin from the estuarine amphipod chaetogammarus marinus (l.). | in the estuarine amphipod chaetogammarus marinus, differences in o(2) binding by haemocyanins (hc) could be related to natural and salinity-related quantitative variation in just one polypeptide subunit (band 2) and not to variations in any of the other seven bands present. band 2 was always present, irrespective of salinity treatment, and naturally makes up 6%-36% of the total hc. however, low salinity exposure (s=4 per thousand for 48-49 h, t=15 degrees c) was accompanied by an increase in the ... | 2003 | 14988799 |
| the lipid composition of hypodermal membranes from the blue crab (callinectes sapidus) changes during the molt cycle and alters hypodermal calcium permeability. | crustaceans are covered by a cuticle that does not grow. in order for an individual to grow, the cuticle must periodically be shed (ecdysis). replacement of the old cuticle with a new one depends on processes that require precise timing and control, yet the nature and location of these controls remain unclear. a candidate site for them is within the hypodermal microvilli. these cellular structures extend through pore canals deep into the acellular cuticular matrix. changes in the lipid compositi ... | 2004 | 14990220 |
| antipeptide antibodies for detecting crab (callinectes sapidus) molt-inhibiting hormone. | in crustaceans, the synthesis of ecdysteroid molting hormones is regulated by molt-inhibiting hormone (mih), a neuropeptide produced by an eyestalk neuroendocrine system, the x-organ/sinus gland complex. using sequence analysis software, two regions of the blue crab (callinectes sapidus) mih peptide were selected for antibody production. two 14-mer peptides were commercially synthesized and used to generate polyclonal antisera. western blot analysis revealed that each antiserum bound to proteins ... | 2002 | 12084515 |
| development of an 18s rrna gene-targeted pcr-based diagnostic for the blue crab parasite hematodinium sp.. | the 18s rrna gene from hematodinum sp., a parasitic dinoflagellate that infects blue crabs, was amplified, cloned, and sequenced. the sequence showed a high similarity (95% at the nucleotide level) to sequences obtained from other dinoflagellate species, including both free-living and symbiotic species. sequence similarity was much lower when compared with parasites of other marine invertebrates with similar life histories and with the 18s rrna gene from the blue crab. based on comparison of seq ... | 2002 | 12093043 |
| environmentally-controlled, density-dependent secondary dispersal in a local estuarine crab population. | the mechanisms driving the pelagic secondary dispersal of aquatic organisms following initial settlement to benthic habitats are poorly characterized. we examined the physical environmental (wind, diel cycle, tidal phase) and biological (ontogenetic, density-dependent) factors that contribute to the secondary dispersal of a benthic marine invertebrate, the blue crab (callinectes sapidus) in pamlico sound, nc, usa. field studies conducted in relatively large (0.05 km2) seagrass beds determined th ... | 2004 | 15146323 |
| effects of hypoxia on gene and protein expression in the blue crab, callinectes sapidus. | increases in hypoxic conditions are one of the major factors responsible for declines in estuarine habitat quality, yet to date there are no indicators for recognizing populations of estuarine organisms that are suffering from chronic hypoxic stress. here we test the hypothesis that alterations in gene and protein expression of antioxidant enzymes and other stress-specific proteins can be used as molecular indicators of hypoxic stress. blue crabs, callinectes sapidus, were exposed to 2-3 ppm do ... | 2004 | 15178114 |
| effects of hypercapnic hypoxia on the clearance of vibrio campbellii in the atlantic blue crab, callinectes sapidus rathbun. | callinectes sapidus, the atlantic blue crab, encounters hypoxia, hypercapnia (elevated co(2)), and bacterial pathogens in its natural environment. we tested the hypothesis that acute exposure to hypercapnic hypoxia (hh) alters the crab's ability to clear a pathogenic bacterium, vibrio campbellii 90-69b3, from the hemolymph. adult male crabs were held in normoxia (well-aerated seawater) or hh (seawater with po(2) = 4 kpa; pco(2) = 1.8 kpa; and ph = 6.7-7.1) and were injected with 2.5 x 10(4) vibr ... | 2004 | 15198944 |
| purification of a soluble glycoprotein from the uncalcified ecdysial cuticle of the blue crab callinectes sapidus and its possible role in initial mineralization. | a heavily glycosylated soluble protein was purified using a combination of lectin affinity and size exclusion chromatography from a soluble extract of uncalcified dorsal cuticle of blue crab callinectes sapidus removed at ecdysis. similarities in apparent molecular mass and carbohydrate composition suggest that this protein is the same species previously shown to disappear from soluble extracts coincidentally with the onset of mineral deposition in the newly exposed post-molt cuticle. the amino ... | 2004 | 15201291 |
| haemolymph parasite of the shore crab carcinus maenas: pathology, ultrastructure and observations on crustacean haplosporidians. | a protozoan parasite with some features of haplosporidians is described from the european shore crab carcinus maenas. the parasite establishes a systemic infection through the haemal sinuses and connective tissues. intracellular stages of the parasite were found within reserve inclusion, connective tissue, and muscle cells, while free forms were present in all haemal spaces. a uninucleate stage appeared to develop to a multinucleate plasmodial stage following multiple mitotic divisions of the nu ... | 2004 | 15212293 |
| bdellovibrios in callinectus sapidus, the blue crab. | bdellovibrios were recovered from the gill tissue of all of 31 crabs sampled and from all samples of epibiota obtained from the ventral shell surface of 15 crabs. the results suggest that the blue crab is a reservoir for bdellovibrios. the association with crabs may be an important factor in the ecology of the bdellovibrios. | 1992 | 16348706 |
| modulation of an integrated central pattern generator-effector system: dopaminergic regulation of cardiac activity in the blue crab callinectes sapidus. | theoretical studies have suggested that the output of a central pattern generator (cpg) must be matched to the properties of its peripheral effector system to ensure production of functional behavior. one way that such matching could be achieved is through coordinated central and peripheral modulation. in this study, morphological and physiological methods were used to examine the sources and actions of dopaminergic modulation in the cardiac system of the blue crab, callinectes sapidus. immunohi ... | 2004 | 15295014 |
| effects of odor flux and pulse rate on chemosensory tracking in turbulent odor plumes by the blue crab, callinectes sapidus. | the ability of animals to track through chemical plumes is often related to properties of evanescent odor bursts and to small-scale mixing process that determine burst properties. however, odor plumes contain variation over a range of scales, and little is known about how variation in the properties of the odor signal on the scale of one to several seconds affects foraging performance. we examined how flux and pulse rate interact to modulate the search behavior of blue crabs, callinectes sapidus ... | 2004 | 15315942 |
| an analysis of the effects of a sacculinid parasite on the external morphology of callinectes sapidus rathbun. | | 1950 | 15420231 |
| metabolic influences of fiber size in aerobic and anaerobic locomotor muscles of the blue crab, callinectes sapidus. | diameters of some white locomotor muscle fibers in the adult blue crab, callinectes sapidus, exceed 500 microm whereas juvenile white fibers are <100 microm. it was hypothesized that aerobically dependent processes, such as metabolic recovery following burst contractions, will be significantly impeded in the large white fibers. in addition, dark aerobic fibers of adults, which rely on aerobic metabolism for both contraction and recovery, grow as large as the white fibers. these large aerobic fib ... | 2004 | 15498950 |
| critical salinity, sensitivity, and commitment of salinity-mediated carbonic anhydrase induction in the gills of two euryhaline species of decapod crustaceans. | two euryhaline species of decapod crustaceans, carcinus maenas and callinectes sapidus, were subjected to a series of acute low-salinity challenges, and changes in carbonic anhydrase (ca) activity in the gills were monitored in order to characterize the nature of salinity-sensitive ca induction. ca activity is uniformly low in all gills of both species at high salinity, but at a critical salinity of 27 ppt, ca induction occurs in the posterior, ion-transporting gills, with ca activity approximat ... | 2005 | 15612006 |
| superoxide dismutase evolution and life span regulation. | superoxide is among the most abundant reactive oxygen species (ros) produced by the mitochondria, and is involved in cellular signaling pathways. superoxide and other ros can damage cellular macromolecules and levels of oxidative damage products are positively correlated with aging. superoxide dismutase (sod) enzymes catalyze the breakdown of superoxide into hydrogen peroxide and water and are therefore central regulators of ros levels. genetic and transgenic manipulation of sod activities in mo ... | 2005 | 15664623 |
| exuviotrophic apostome ciliates from crustaceans of st. andrew bay, florida, and a description of gymnodinioides kozloffi n. sp. | gymnodinioides kozloffi n. sp. is described from the eelgrass broken-back shrimp hippolyte zostericola. the species is distinct from others in the apostome genus gymnodinioides in that the trophont ciliature has a small group of kinetosomes located to the right of kinety 9a, and kinety 1 and 2 are divided. other apostome morphologies are described from many decapod crustaceans from st. andrew bay, florida, including gymnodinioides inkystans, hyalophysa chattoni, and variants of both h. chattoni ... | 2004 | 15666721 |
| early pattern of calcification in the dorsal carapace of the blue crab, callinectes sapidus. | the pattern of calcium carbonate deposition was observed in the dorsal carapace of premolt (d2-d3) and early postmolt (0-48 h) blue crabs, callinectes sapidus, using scanning (sem) and transmission (tem) electron microscopy. samples of dorsal carapace for sem were quick-frozen in liquid nitrogen, subsequently lyophilized, and viewed using secondary and backscattered electrons as well as x-ray maps of calcium. pieces of lyophilized cuticle were also embedded in epoxy resin and subsequently sectio ... | 2005 | 15688443 |
| the effects of rapid salinity change on in vivo arginine kinase flux in the juvenile blue crab, callinectes sapidus. | the effect of acclimation salinity and salinity changes on the concentration of high-energy phosphate metabolites and arginine kinase (ak) flux was examined in vivo in juvenile blue crabs using 31p-nuclear magnetic resonance (nmr). crabs were acclimated for 7 days to a salinity of 5 or 35 per thousand and then placed in a flow apparatus that could sustain the animals while nmr spectra were acquired. crabs were subjected to either hyperosmotic salinity changes, where an animal acclimated to 5 per ... | 2003 | 12831772 |
| a comparison of different processing methods for picked blue crab (callinectes sapidus). | five methods for producing picked crab meat from cooked blue crab (callinectes sapidus) were evaluated for internal food temperatures and bacterial numbers at various process points. whole shell-on crabs, crab cores ("backed" crabs with carapace removed), and crab meat samples were analyzed for standard plate count, total coliforms, fecal coliforms, escherichia coli, and staphylococcus aureus. for three of the processes, crabs were backed and washed a substantial time before picking; one of the ... | 2005 | 15726982 |
| expression of a serine proteinase homolog prophenoloxidase-activating factor from the blue crab, callinectes sapidus. | tanning, or sclerotization, of crustacean cuticle provides initial reinforcement by cross linking cuticular proteins attached to the cuticle chitin-fiber matrix. this process is catalyzed in part by phenoloxidase, which is under the control of a serine protease activation cascade. the cdna of a prophenoloxidase-activating factor (ppaf) was cloned and sequenced from the hypodermal tissue of the blue crab, callinectes sapidus. it codes for a serine proteinase homolog containing a single clip domai ... | 2005 | 15763507 |
| k+-phosphatase activity of gill (na+, k+)-atpase from the blue crab, callinectes danae: low-salinity acclimation and expression of the alpha-subunit. | the kinetic properties of a microsomal gill (na(+), k(+)) atpase from the blue crab, callinectes danae, acclimated to 15 per thousand salinity for 10 days, were analyzed using the substrate p-nitrophenylphosphate. the (na(+), k(+))-atpase hydrolyzed the substrate obeying michaelian kinetics at a rate of v=102.9+/-4.3 u.mg(-1) with k(0.5)=1.7+/-0.1 mmol.l(-1), while stimulation by magnesium (v=93.7+/-2.3 u.mg(-1); k(0.5)=1.40+/-0.03 mmol.l(-1)) and potassium ions (v=94.9+/-3.5 u.mg(-1); k(0.5)=2. ... | 2005 | 15776418 |
| isolation and structure elucidation of feeding deterrent diterpenoids from the sea pansy, renilla reniformis. | four new briarane diterpenoids, renillins a-d (1-4), and the known compound renillafoulin c (5) were isolated from the sea pansy, renilla reniformis. the structures and relative stereochemistry were elucidated by the interpretation of spectroscopic data. using laboratory feeding assays, all compounds tested at natural concentrations significantly deterred feeding by the predatory lesser blue crab, callinectes similis, while renillins c (3) and d (4) also deterred feeding by the predatory mummich ... | 2005 | 15844939 |
| trimeric g proteins in crustacean (callinectes sapidus) y-organs: occurrence and functional link to protein synthesis. | crustacean y-organs produce ecdysteroid molting hormones. regulation of ecdysteroidogenesis appears to be complex, involving regulatory ligands (including but not limited to molt-inhibiting hormone, an eyestalk neurohormone) and the capacity of the y-organs to respond to those ligands. available data indicate cell signaling pathways involving camp, cgmp, or both may be involved in regulation of y-organ function. trimeric g proteins link receptor occupancy to regulation of intracellular camp leve ... | 2005 | 15880757 |
| effect of salinity on osmoregulatory patch epithelia in gills of the blue crab callinectes sapidus. | in euryhaline crabs, ion-transporting cells are clustered into osmoregulatory patches on the lamellae of the posterior gills. to examine changes in the branchial osmoregulatory patch in the blue crab callinectes sapidus in response to change in salinity and to correlate these changes with other osmoregulatory responses, crabs were acclimated to a range of salinities between 10 and 35 ppt. when crabs that had been acclimated to 35 ppt were subsequently transferred to 10 ppt, both the size of the ... | 2006 | 16641518 |
| four differentially expressed cdnas in callinectes sapidus containing the rebers-riddiford consensus sequence. | decapod crustaceans such as callinectes sapidus, the blue crab, provide unique opportunities to study proteins involved in biomineralization. subsequent to each molt, the previously deposited soft cuticle is calcified while the postecdysial layers are simultaneously deposited and mineralized. though the majority of the exoskeleton hardens, morphologically similar cuticle at the joints, called arthrodial membrane, remains flexible. it seems reasonable that hypodermal cells producing these cuticle ... | 2005 | 15939643 |
| chlordane contamination in selected estuarine and coastal marine finfish and shellfish of new jersey, usa. | analysis of chlordane contamination in selected finfish and shellfish species from estuarine and coastal marine waters of new jersey, usa, indicates consistently highest organochlorine pesticide levels in samples from the north and northeast regions of the state. gas chromatographic analysis of tissue samples from four finfish species (american eel, anguilla rostrata; bluefish, pomatomus saltatrix; striped bass, morone saxatilis; and weakfish, cynoscion regalis) and one shellfish species (blue c ... | 1996 | 15093520 |
| ecological risk assessment of neem-based pesticides. | a tiered process was used to evaluate the risks of pure azadirachtin (aza) and two neem-based insecticides (neemix and bioneem) on six aquatic animals [crayfish (procambarus clarkii), white shrimp (penaeus setiferus), grass shrimp (palaemonetes pugio), blue crabs (callinectes sapidus), water fleas (daphnia pulex), and mosquito larvae (culex quinquefasciatus)] through short term acute toxicity tests. the risk was calculated using the level of concern endpoints (q values) and relative hazard index ... | 2004 | 15132337 |
| the complete mitochondrial genome of the stomatopod crustacean squilla mantis. | animal mitochondrial genomes are physically separate from the much larger nuclear genomes and have proven useful both for phylogenetic studies and for understanding genome evolution. within the phylum arthropoda the subphylum crustacea includes over 50,000 named species with immense variation in body plans and habitats, yet only 23 complete mitochondrial genomes are available from this subphylum. | 2005 | 16091132 |
| molecular cloning and characterisation of cytosolic manganese superoxide dismutase (cytmn-sod) from the giant freshwater prawn macrobrachium rosenbergii. | a cytosolic manganese superoxide dismutase (cytmn-sod) cdna was cloned from the hepatopancreas of giant freshwater prawn macrobrachium rosenbergii using reverse transcription polymerase chain reaction (rt-pcr) by degenerate primers. both 3'- and 5'-regions were isolated by rapid amplification of cdna end race method. analysis of nucleotide sequence revealed that the cytmn-sod cdna clone consists of 1339 bp with an open reading frame of 858 bp encoding a protein of 286 amino acids. the calculated ... | 2006 | 16154362 |
| a review of the parasitic dinoflagellates hematodinium species and hematodinium-like infections in marine crustaceans. | parasitic dinoflagellates in the genus hematodinium are important parasites of marine crustacea. outbreaks of these parasites have damaged commercial stocks of norway lobster nephrops norvegicus, snow crab chionoecetes opilio, tanner crab c. bairdi, american blue crab callinectes sapidus, and velvet swimming crab necora puber. species of hematodinium can reach high enough levels to regulate their host populations, but mortalities are also centred on the unfished juveniles and females, hosts not ... | 2005 | 16175968 |
| phylogenetic position of the copepod-infesting parasite syndinium turbo (dinoflagellata, syndinea). | sequences were determined for the nuclear-encoded small subunit (ssu) rrna and 5.8s rrna genes as well as the internal transcribed spacers its1 and its2 of the parasitic dinoflagellate genus syndinium from two different marine copepod hosts. syndinium developed a multicellular plasmodium inside its host and at maturity free-swimming zoospores were released. syndinium plasmodia in the copepod paracalanus parvus produced zoospores of three different morphological types. however, full ssu rdna sequ ... | 2005 | 16310746 |
| molecular cloning and characterisation of copper/zinc superoxide dismutase (cu,zn-sod) from the giant freshwater prawn macrobrachium rosenbergii. | a copper/zinc superoxide dismutase (cu,zn-sod) cdna was cloned from the hepatopancreas of giant freshwater prawn macrobrachium rosenbergii using reverse transcription-polymerase chain reaction (rt-pcr) by degenerate primers. both 3'- and 5'-regions were isolated by the rapid amplification of cdna ends method. analysis of nucleotide sequence revealed that the cu,zn-sod cdna clone consists of 845 bp with an open reading frame of 603 bp encoding a protein of 201 amino acids with a 22 amino acid sig ... | 2006 | 16356736 |
| effects of eyestalk ablation on carbonic anhydrase activity in the euryhaline blue crab callinectes sapidus: neuroendocrine control of enzyme expression. | carbonic anhydrase (ca) activity in the gills of the euryhaline blue crab, callinectes sapidus, was measured in response to acute low-salinity transfer and treatment with eyestalk ablation (esa) in an attempt to elucidate potential regulatory mechanisms of salinity-mediated ca induction. esa alone resulted in an approximate doubling of ca activity in the posterior, ion-transporting gills of crabs acclimated to 35 ppt. transfer of intact crabs to 28 ppt, a salinity at which the blue crab is still ... | 2006 | 16358277 |
| the utilization of lipovitellin during blue crab (callinectes sapidus) embryogenesis. | embryos of the blue crab callinectes sapidus develop in egg sacs carried on the abdomen of the female. they develop over a period of 10-13 days at 28 degrees c and are nutritionally dependent on yolk until they emerge from the egg sacs as free-swimming zoeae. the principal component of blue crab yolk is lipovitellin (lpii), a water-soluble lipoprotein composed of approximately equal amounts of lipid and protein. we followed changes in the concentration of apoproteins of lpii during embryogenesis ... | 2006 | 16406827 |
| molecular cloning of a putative receptor guanylyl cyclase from y-organs of the blue crab, callinectes sapidus. | crustacean molt-inhibiting hormone (mih), a polypeptide produced by neurosecretory cells in eyestalk ganglia, suppresses the synthesis of ecdysteroid molting hormones by paired y-organs. data from several sources indicate the effects of mih are mediated, at least in part, by a cgmp second messenger. based on these and related findings, our working hypothesis is that the mih receptor is a receptor guanylyl cyclase (rgc). in studies reported here, we used a pcr-based cloning strategy (rt-pcr follo ... | 2006 | 16426608 |
| gill area, permeability and na+ ,k+ -atpase activity as a function of size and salinity in the blue crab, callinectes sapidus. | juvenile blue crabs, callinectes sapidus, extensively utilize oligohaline and freshwater regions of the estuary. with a presumptively larger surface-area-to-body weight ratio, juvenile crabs could experience osmo- and ionoregulatory costs well in excess of that of adults. to test this hypothesis, crabs ranging over three orders of magnitude in body weight were acclimated to either sea water (1,000 mosm) or dilute sea water (150 mosm), and gill surface area, water and sodium permeabilities (calcu ... | 2006 | 16432886 |
| regulation of protein synthesis in y-organs of the blue crab (callinectes sapidus): involvement of cyclic amp. | paired y-organs secrete ecdysteroid hormones that control cycles of growth and molting in crustaceans. y-organs are regulated, at least in part, by molt-inhibiting hormone (mih), a polypeptide produced and released by the x-organ/sinus gland complex of the eyestalks. in the present studies, crab (callinectes sapidus) y-organs were incubated in vitro in the presence of [(35)s]methionine, and cyclic nucleotide analogs or experimental agents that influence the camp signaling pathway. in 4-hr incuba ... | 2006 | 16493643 |
| comparative hemolytic activity of vibrio parahaemolyticus and related vibrios. | the hemolytic activities of 91 strains of vibrio parahaemolyticus isolated from human diarrheal stools, sea fish, and sea water; 21 suspected v. parahaemolyticus cultures isolated from wound infections; 14 nonpathogenic marine vibrios; and 21 v. parahaemolyticus isolated from moribund blue crabs callinectes sapidus were compared. potentially pathogenic v. parahaemolyticus strains could be differentiated from the related nonpathogenic marine vibrios, because the former hemolyzed hamster, sheep, a ... | 1970 | 16557747 |
| two new species of epistylis (ciliophora: peritrichida) on the blue crab (callinectes sapidus) in the gulf of mexico. | two epibiotic peritrichs infested the blue crab, callinectes sapidus, from the gulf of mexico, mississippi, usa. epistylis callinectes n. sp. was isolated from the epipods of maxillipeds, bases of gill-cleaning setae, and gills, and epistylis clampi n. sp. was isolated from the exterior surfaces of the exoskeleton. epistylis callinectes has short, symmetrically and dichotomously branched stalks; its zooid is elongate ovoid and conspicuously longer than the individual stalk branches, measuring 40 ... | 2006 | 16579810 |
| the decapod crustacean circulatory system: a case that is neither open nor closed. | historically, the decapod crustacean circulatory system has been classed as open. however, recent work on the blue crab, callinectes sapidus, suggests the circulatory system may be more complex than previously described. corrosion casting techniques were refined and used to map the circulatory system of a variety of crab species (order: decapoda; family: cancridae) to determine if the complexity observed in the blue crab was present in other species. seven arteries arose from the single chambere ... | 2005 | 15683568 |
| hard clams (mercenaria mercenaria) evaluate predation risk using chemical signals from predators and injured conspecifics. | hard clams, mercenaria mercenaria, are sessile, filter-feeding organisms that are heavily preyed upon by blue crabs, which find their clam prey using chemical cues. clams may evade blue crabs by reducing their pumping (feeding) behavior when a threat is perceived. the purpose of this study was to determine the type of signals that clams use to detect consumers. clams decreased their pumping time in response to blue crabs and blue crab effluent, but not to crab shells, indicating that chemical si ... | 2006 | 16586040 |
| what is molt-inhibiting hormone? the role of an ecdysteroidogenesis inhibitor in the crustacean molting cycle. | the in vivo molt-inhibitory effects of the ecdysone biosynthesis inhibitors 3-hydroxy-l-kynurenine and xanthurenic acid were investigated. these ecdysone biosynthesis inhibitors, isolated from the eyestalks of blue crabs (callinectes sapidus), were injected into eyestalk-ablated crayfish (procambarus clarkii). the active factor was found to be species-nonspecific within crabs and crayfish. the seasonal profiles of the xanthurenic acid and ecdysone titers exhibited a staggered relationship. moreo ... | 1989 | 16594067 |
| the effects of hypoxia and ph on phenoloxidase activity in the atlantic blue crab, callinectes sapidus. | in its natural coastal and estuarine environments, the blue crab, callinectes sapidus, often encounters hypoxia, accompanied by hypercapnia (increased co2) and an associated decrease in water ph. previous studies have shown that exposure to hypercapnic hypoxia (hh) impairs the crab's ability to remove culturable bacteria from its hemolymph. in the present study we demonstrate that the activity of phenoloxidase (po), an enzyme critical to antibacterial immune defense in crustaceans, is decreased ... | 2006 | 16616537 |
| cloning and characterisation of mitochondrial manganese superoxide dismutase (mtmnsod) from the giant freshwater prawn macrobrachium rosenbergii. | a cdna encoding a mitochondrial manganese superoxide dismutase (mtmnsod) was cloned from the hepatopancreas of giant freshwater prawn macrobrachium rosenbergii using reverse transcription polymerase chain reaction (rt-pcr) by degenerate primers. both 3'- and 5'-regions were isolated by rapid amplification of cdna end (race) pcr method. analysis of nucleotide sequence revealed that the mtmnsod full-length cdna consists of 1202bp containing an open reading frame of 654bp, which encodes a protein c ... | 2006 | 16621606 |
| molecular cloning of a cdna encoding a crustacean hyperglycemic hormone from eyestalk ganglia of the blue crab, callinectes sapidus. | crustacean hyperglycemic hormone (chh), a polypeptide with multiple physiological effects, was first identified in the x-organ/sinus gland neurosecretory system of the eyestalks. in studies reported here, we used a pcr-based cloning strategy (rt-pcr followed by 5'- and 3'-race) to clone from blue crab (callinectes sapidus) eyestalk ganglia a cdna (cschh-1) encoding a putative chh preprohormone. sequence analysis revealed the preprohormone included all structural features previously reported for ... | 2006 | 16631756 |
| incremental ecological exposure risks from contaminated sediments in an urban estuarine river. | estuaries in urban regions present unique environmental management challenges. ecosystems in urban estuaries are typically impacted by habitat loss and degradation, watershed modification, and nonpoint and point sources of many chemicals. restoring such systems requires an understanding of the relative contribution of various stressors to overall ecological conditions and an understanding of shifting patterns of stress over time. in this article, we present the results of a multiparameter enviro ... | 2005 | 16639904 |
| when r-selection may not predict introduced-species proliferation: predation of a nonnative oyster. | predicting outcomes of species introductions may be enhanced by integrating life-history theory with results of contained experiments that compare ecological responses of exotic and analogue native species to dominant features of the recipient environment. an asian oyster under consideration for introduction to the chesapeake bay, usa, the rapidly growing suminoe oyster (crassostrea ariakensis), may not be as successful an invader as its r-selected life history suggests if the trade-off for rapi ... | 2006 | 16711058 |
| a comparison of blue crab and bivalve delta15n tissue enrichment in two north carolina estuaries. | stable isotope analyses (delta(15)n) were used to examine invertebrate tissue enrichment in two north carolina estuaries with differing amounts of nutrient loading. bivalves collected from a nutrient sensitive estuary yielded a significant difference in mean nitrogen isotopic composition of tissue (10.4 per thousand+/-0.82; n=66) compared to bivalves collected from a less nutrient sensitive estuary (6.4 per thousand+/-0.63; n=45). similarly, blue crabs from nutrient sensitive sites had a nitroge ... | 2007 | 16714075 |
| a sex-specific metabolite identified in a marine invertebrate utilizing phosphorus-31 nuclear magnetic resonance. | hormone level differences are generally accepted as the primary cause for sexual dimorphism in animal and human development. levels of low molecular weight metabolites also differ between men and women in circulating amino acids, lipids and carbohydrates and within brain tissue. while investigating the metabolism of blue crab tissues using phosphorus-31 nuclear magnetic resonance, we discovered that only the male blue crab (callinectes sapidus) contained a phosphorus compound with a chemical shi ... | 2007 | 17712428 |
| does intracellular metabolite diffusion limit post-contractile recovery in burst locomotor muscle? | post-metamorphic growth in the blue crab entails an increase in body mass that spans several orders of magnitude. the muscles that power burst swimming in these animals grow hypertrophically, such that small crabs have fiber diameters that are typical of most cells (<60 microm) while in adult animals the fibers are giant (>600 microm). thus, as the animals grow, their muscle fibers cross and greatly exceed the surface area to volume ratio (sa:v) and intracellular diffusion distance threshold tha ... | 2005 | 16000534 |
| gill microsomal (na+,k+)-atpase from the blue crab callinectes danae: interactions at cationic sites. | euryhaline crustaceans tolerate exposure to a wide range of dilute media, using compensatory, ion regulatory mechanisms. however, data on molecular interactions occurring at cationic sites on the crustacean gill (na+,k+)-atpase, a key enzyme in this hyperosmoregulatory process, are unavailable. we report that na+ binding at the activating site leads to cooperative, heterotropic interactions that are insensitive to k+. the binding of k+ ions to their high affinity sites displaces na+ ions from th ... | 2005 | 16055367 |
| accumulation of organic and inorganic contaminants in shellfish collected in estuarine waters near pensacola, florida: contamination profiles and risks to human consumers. | we conducted a screening level assessment of contaminants in blue crabs (callinectes sapidus) and oysters (crassostrea virginica) from bays and bayous in the pensacola, fl area. tissue samples were analyzed for 17 dioxins/furans, 12 dioxin-like pcb (dl-pcbs) congeners, mercury, and various metals. contaminant levels were compared to screening values (sv) calculated using u.s. epa recommendations for establishing consumption advisories. all sampling locations exceeded the sv (0.098pgg(-1)) for di ... | 2007 | 16872729 |
| a reaction-diffusion analysis of energetics in large muscle fibers secondarily evolved for aerobic locomotor function. | the muscles that power swimming in the blue crab, callinectes sapidus, grow hypertrophically, such that in juvenile crabs the cell diameters are <60 microm, whereas fibers of the adult crabs often exceed 600 microm. thus, as these animals grow, their muscle fibers greatly exceed the surface area to volume ratio and intracellular diffusion distance limits of most cells. previous studies have shown that arginine phosphate (ap) recovery in the anaerobic (light) fibers, which demonstrate a fiber siz ... | 2006 | 16943501 |
| immune defense reduces respiratory fitness in callinectes sapidus, the atlantic blue crab. | crustacean gills function in gas exchange, ion transport, and immune defense against microbial pathogens. hemocyte aggregates that form in response to microbial pathogens become trapped in the fine vasculature of the gill, leading to the suggestion by others that respiration and ion regulation might by impaired during the course of an immune response. in the present study, injection of the pathogenic bacterium vibrio campbellii into callinectes sapidus, the atlantic blue crab, caused a dramatic ... | 2006 | 16946241 |
| expression profiles of na+,k+-atpase during acute and chronic hypo-osmotic stress in the blue crab callinectes sapidus. | during acclimation to dilute seawater, the specific activity of na+,k+-atpase increases substantially in the posterior gills of the blue crab callinectes sapidus. to determine whether this increase occurs through regulation of pre-existing enzyme or synthesis of new enzyme, mrna and protein levels were measured over short (<24 h) and long (18 days) time courses. na+,k+-atpase expression, both mrna and protein, did not change during the initial 24-h exposure to dilute seawater (10 ppt salinity). ... | 2006 | 16946242 |
| metal concentrations in blue crab (callinectes sapidus) and mullet (mugil cephalus) in iskenderun bay, northern east mediterranean, turkey. | | 2006 | 16977519 |
| identification and developmental expression of mrnas encoding crustacean cardioactive peptide (ccap) in decapod crustaceans. | full-length cdnas encoding crustacean cardioactive peptide (ccap) were isolated from several decapod (brachyuran and astacuran) crustaceans: the blue crab callinectes sapidus, green shore crab carcinus maenas, european lobster homarus gamarus and calico crayfish orconectes immunis. the cdnas encode open reading frames of 143 (brachyurans) and 139-140 (astacurans) amino acids. apart from the predicted signal peptides (30-32 amino acids), the conceptually translated precursor codes for a single co ... | 2006 | 16985202 |
| the mitochondrial manganese superoxide dismutase gene in chinese shrimp fenneropenaeus chinensis: cloning, distribution and expression. | manganese superoxide dismutase (mnsod) plays an important role in crustacean immune defense reaction by eliminating oxidative stress. knowledge on mnsod at molecular level allows us to understand its regulatory mechanism in crustacean immune system. a novel mitochondrial manganese superoxide dismutase (mmnsod) was cloned from hepatopancreas of chinese shrimp fenneropenaeus chinensis by 3' and 5' rapid amplification of cdna ends (race) pcr. the full-length cdna consists of 1185bp with a 660bp ope ... | 2007 | 17097141 |
| differences in enzyme activities between two species of hematodinium, parasitic dinoflagellates of crustaceans. | parasitic dinoflagellates of the genus hematodinium infect several commercially important decapod crustaceans. different species of hematodinium have different levels of virulence in their respective hosts. enzyme activities were studied from two species of hematodinium, one isolated from the norway lobster (nephrops norvegicus) and the other from the american blue crab (callinectes sapidus). we report the identification of differences in secretion of acid phosphatase (ap) and leucine arylamidas ... | 2007 | 17156792 |
| differential growth and moulting characteristics of the blue crab, callinectes sapidus rathbun. | | 1949 | 18113443 |
| molecular cloning, characterization and expression of a masquerade-like serine proteinase homologue from black tiger shrimp penaeus monodon. | a full-length cdna of a masquerade-like serine proteinase homologue (pmmassph) of penaeus monodon was cloned and characterized by rapid amplification cdna end (race) method. the complete cdna sequence of 1958bp contains an open reading frame (orf) of 1572bp, encoding a 523 amino acid protein including a 19 amino acid signal peptide. the calculated molecular mass of the mature protein (504 amino acids) is 51.58kda with an estimated pi of 4.86. pmmassph has most of the structural characteristics o ... | 2007 | 17174571 |