Publications
Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
---|
ponasterone a: a new ecdysteroid from the embryos and serum of brachyuran crustaceans. | the apolar ecdysteroid present in the developing embryo of the blue crab, callinectes sapidus rathbun, is tentatively identified as ponasterone a (2 beta, 14 alpha, 20,22-pentahydroxy-5, beta-cholest-7-en-6-one) on the basis of chromatographic, immunological, and mass spectral evidence. the apolar ecdysteroid present in the serum of land crabs, gecarcinus lateralis, in the late premolt stages of the intermolt cycle is also tentatively identified as ponasterone a on the basis of chromatographic a ... | 1979 | 538780 |
the importance of predation and competition in organizing the intertidal epifaunal communities of barnegat inlet, new jersey. | community organization was studied by experiment and observation from october 1972-october 1974 in the marine epifaunal assemblages at each end of barnegat inlet, new jersey. the rock jetty at the wave-exposed eastern end of the inlet possesses an intertidal community with the following attributes: (1) a high intertidal zone dominated by the barnacle, balanus balanoides, but also occupied by the blue mussel, mytilus edulis, in rock crevices, (2) a mid and low intertidal zone with usually <10% fr ... | 1979 | 28309374 |
calcium and the tonic release of transmitter at a non-impulsive synapse in the crab. | depolarization-transmitter release coupling was studied in the promotor stretch receptor/motoneuron synapse of the crab. callinectes sapidus, a preparation in which presynaptic action potentials do not occur. intracellular microelectrode recordings were made from the presynaptic terminal and from the somata of postsynaptic motoneurons while injecting current pulses into the peripheral stretch receptor dendrite with the aid of the sucrose-gap. 1. for short current pulses, the relationship between ... | 1980 | 6109020 |
uptake and survival of enteric viruses in the blue crab, callinectes sapidus. | uptake of poliovirus 1 by the blue crab, callinectes sapidus, was measured to assess the likelihood of contamination by human enteric viruses. virus was found in all parts of the crab within 2 h after the crab was placed in contaminated artificial seawater. the highest concentrations of virus were found in the hemolymph and digestive tract, but the meat also contained virus. the concentration of virus in the crabs was generally less than in the surrounding water. changes in salinity did not subs ... | 1981 | 6261683 |
subunit structure and dissociation of callinectes sapidus hemocyanin. | the hemocyanin of the blue crab, callinectes sapidus has two major components sedimenting with approximate sedimentation coefficients of 17 s and 25 s. molecular weight data based on light scattering and sedimentation equilibrium measurements at ph 7.8 suggest that the two components have molecular weights of approximately 450 000 and 900 000 in the presence of stabilizing ca2+. in the absence of ca2+, the molecular weights are found to be about 5% lower, suggesting some dissociation of the hemo ... | 1981 | 7213799 |
toxicity of ozonated estuarine water to juvenile blue crabs (callinectes sapidus) and juvenile atlantic menhaden (brevoortia tyrannus). | 1981 | 7248539 | |
effect of the amino acid histidine on the uptake of cadmium from the digestive system of the blue crab, callinectes sapidus. | 1981 | 7296034 | |
amiloride-sensitive ammonium and sodium ion transport in the blue crab. | in the estuarine crab, callinectes sapidus, net nh4+ efflux was twice as high in animals acclimated to 17% salinity seawater (sw) (0.495 +/- 0.084 mumol . h-1 . g wet wt-1, n = 7) than in animals acclimated to full-strength 35% sw (0.212 +/- 0.028 mumol . h-1 . g-1, n = 7). amiloride (3 x 10(-4) m) in the external sw reversibly inhibited these effluxes by 63 +/- 6% (n = 6) and 67 +/- 6% (n = 5), respectively. unidirectional na+ influx was reversibly inhibited 42 +/- 6% (n = 7) by amiloride in 17 ... | 1981 | 7304782 |
specificity for tail fibers of a humoral crab factor neutralizing t2 bacteriophage. | it is now becoming clear that invertebrates, animals lacking the ability to make humoral antibodies, are capable of recognizing self from non-self. in several instances this recognition is manifest in normal ("unimmunized") animals by a rapid clearance of certain foreign materials from the circulation one example of such a rapid innate reaction involves the clearance of t2 bacteriophage from the blue crab (1). other studies have indicated that blue crab plasma contained a factor capable of neutr ... | 1982 | 7067888 |
heavy metal ion interactions with callinectes sapidus hemocyanin: structural and functional changes induced by a variety of heavy metal ions. | hemocyanins are oligomeric proteins that reversibly bind oxygen. the oxygen binding site is a binuclear copper center bound to the protein by amino acid side chains. the hemocyanin of the blue crab, callinectes sapidus, occurs in vivo as a mixture of 25s dodecamers and 16s hexamers, whose oxygen binding properties are identical. four heavy metals have been used as probes of structure and function in this hemocyanin system. divalent cations of cadmium, copper, mercury, and zinc induced an indefin ... | 1982 | 7093201 |
incidence of vibrio species associated with blue crabs (callinectes sapidus) collected from galveston bay, texas. | bacteria were readily isolated from the hemolymph of a majority (88%) of the blue crabs collected from galveston bay, texas. the hemolymph of most crabs contained moderate (greater than 10(3) bacteria/ml) to heavy (greater than (10(5) bacteria/ml) infections. large variances were observed in the bacterial number associated with individual crabs, but no significant difference was observed between the mean bacterial levels in the hemolymph of crabs collected during different seasons of the samplin ... | 1982 | 7103475 |
cadmium-binding proteins from blue crabs (callinectes sapidus) environmentally exposed to cadmium. | 1982 | 7106072 | |
diurnal changes in compound eye fine structure in the blue crab callinectes. 1. differences between noon and midnight retinas on an ld 11:13 cycle. | 1982 | 7200529 | |
salinity adaptation of hco3--dependent atpase activity in the gills of blue crab (callinectes sapidus). | a bicarbonate-dependent atpase (ec 3.6.1.3) was found in microsomal preparations from blue crab gills. when the crabs were transferred to low salinity (200 mosmolal) from seawater (1000 mosmolal), the hco3- dependent atpase increased in all gill pairs, reaching its new steady state in 2 weeks. the greatest increase occurred in the sixth and seventh gill pairs (approx. 2.5-fold). maximal enzyme activity was observed at an mg2+ concentration of 2 mm and an optimal ph of 7.8. the apparent ka for hc ... | 1982 | 6125214 |
concentration of rotavirus and enteroviruses from blue crabs (callinectes sapidus). | a simple method for concentration and detection of rotavirus and enteroviruses in the blue crab is described. virus was separated from tissue homogenates at ph 9.5, concentrated by adsorption to protein precipitates at ph 3.5, and recovered by elution of precipitates at ph 9.2. test samples of 12 to 15 ml were produced from an initial 100 g of crab tissues. cat-floc precipitation was used to remove sample toxicity for cell cultures. recovery effectiveness averaged 52% with poliovirus 1, echoviru ... | 1983 | 6318667 |
metal ion interactions with limulus polyphemus and callinectes sapidus hemocyanins: stoichiometry and structural and functional consequences of calcium(ii), cadmium(ii), zinc(ii), and mercury(ii) binding. | hemocyanins are oligomeric metalloproteins containing binuclear copper centers that reversibly combine with oxygen molecules. the structural stability and functional properties of these proteins are modified by divalent cations. equilibrium dialysis was used to study the reversible interaction of callinectes sapidus and limulus polyphemus hemocyanins with the divalent cations calcium, cadmium, zinc, copper, and mercury. the number of binding sites and association constants for each cation were o ... | 1983 | 6626526 |
the intracellular partitioning of trace metals in marine shellfish. | marine organisms have evolved a number of metabolic strategies to deal with potentially toxic trace metals. to determine how "detoxification" mechanisms such as metal-binding proteins and concretions are involved in the intracellular partitioning of trace metals in marine shellfish, the oyster, crassostrea virginica, and the blue crab, callincetes sapidus, were exposed to controlled levels of trace metals. oysters accumulated cadmium readily and produced specific low molecular weight, cadmium-bi ... | 1983 | 6879150 |
distribution ofvibrio cholerae in two florida estuaries. | the distribution ofvibrio cholerae was examined in 2 florida estuaries, apalachicola and tampa bay.vibrio cholerae serotype non-01 was the most abundant serotype, being isolated from 45% of the oyster samples, 30% of the sediments, 50% of the waters, and 75% of the blue crabs.vibrio cholerae serotype 01 was isolated from only one oyster sample. strong linear correlations betweenv. cholerae and temperature, salinity, or the other physical/chemical parameters measured,escherichia coli, or fecal co ... | 1983 | 24221617 |
characterization of a sex pheromone in the blue crab,callinectes sapidus: crustecdysone studies. | the molting hormone/sex pheromone hypothesis of kittredge and takahashi (1972) and kittredge et al. (1971) was explored inc. sapidus. two concentrations of crustecdysone (5 × 10(-5) m and 5 × 10(-6) m) were presented to male crabs in a bioassay system in which courtship behavior was monitored. the results demonstrate that crustecdysone does not stimulate courtship in this species. the physical properties of crustecdysone were also compared to those of the partially purified sex pheromone derived ... | 1984 | 24318783 |
allosteric modulation of callinectes sapidus hemocyanin by binding of l-lactate. | hemocyanin of the blue crab callinectes sapidus has the typical structure of crustacean hemocyanins in that its smallest in vivo structure is a hexamer of subunits each having a molecular mass of approximately 75 000. as found in the blood, callinectes hemocyanin consists of a mixture of hexamers and dodecamers (typically 1:4). as in other crustacean hemocyanins, the affinity with which oxygen binds to the binuclear copper site has been reported to be very sensitive to ph and to a variety of ino ... | 1984 | 25856833 |
recognition of xenogeneic proteins by the blue crab: dissociation of the clearance and degradation reactions and lack of involvement of circulating hemocytes and humoral factors. | blue crabs clear foreign proteins from the circulation to the gills in a manner that can be explained by postulating the participation of a finite number of naturally occurring quasi-specific receptors. the rate of this clearance reaction is not increased by previous exposure to the foreign protein although recovery to the normal rate of clearance after high level blockade is quite rapid. the cleared foreign proteins are degraded in the gills in a relatively nonspecific fashion suggestive of a c ... | 1984 | 6724091 |
total lipid and cholesterol content in the blue crab, callinectes sapidus rathbun. | total lipid and cholesterol concentrations in hepatopancreas, gonad and muscle were analyzed for 70 blue crabs. the concentrations were highest in hepatopancreas, then gonad, and muscle was the lowest. in male crabs, the concentrations decreased from the immature stage (feeding and growth stage) to the mature stage (breeding stage), and from august to september (breeding period) in mature males. in female crabs, the concentrations were comparatively high for peelers (pre-molting stage) and matur ... | 1984 | 6744830 |
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 |
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 |
acid-base regulation during exercise and recovery in the blue crab, callinectes sapidus. | during swimming activity callinectes sapidus incurred a severe hemolymph acidosis due to elevated levels of pco2 and lactate. although hemolymph lactate concentration rose steadily during 1 h of exercise, hemolymph ph was maximally depressed within the first 15 min. a discrepancy between the quantities of lactate and h+ released from the tissues into the hemolymph is explained by a large apparent efflux of h+ into the ambient seawater, presumably via a branchial ion exchange process. ammonia exc ... | 1984 | 6528111 |
microsomal cytochromes p-450 from marine crabs. | cytochromes p-450 were isolated from the hepatopancreas of several species of crabs (libinia emarginata, callinectes sapidus, menippe mercenaria and uca minax). elution profiles from an ion exchange column showed similar profiles for all species, indicating one broad cytochrome p-450 peak eluting at 0.2 m k cl. hydroxyapatite chromatography resolved the p-450 into three forms (cytochromes p-450i, p-450ii and p-450iii). the forms of cytochrome p-450 in the different crabs were compared with respe ... | 1984 | 6149863 |
source of vibrio spp. found in the hemolymph of the blue crab, callinectes sapidus. | 1985 | 4031533 | |
incidence of bacteremia in stressed and unstressed populations of the blue crab, callinectes sapidus. | the incidence of bacteremia in the blue crab, callinectes sapidus, is reported to be in excess of 80%. because these results have been controversial, a field study was initiated to determine the effect of commercial capture and handling stresses on the incidence and levels of infection in blue crabs. the majority (75%) of "unstressed" crabs which were captured individually and bled immediately upon removal from the water were bacteremic, with a geometric mean level of infection of 14 cfu/ml of h ... | 1985 | 4051486 |
bicarbonate-chloride exchange in gill plasma membranes of blue crab. | the uptake of chloride was studied in gill plasma membrane vesicles from low-salinity-adapted blue crabs (callinectes sapidus). cl- uptake was not na+ dependent. however, when a hco-3 gradient (in greater than out) was imposed across the membrane, a transient overshoot of about 2.5-fold was produced. approximately 90% of the cl- uptake reflected entry into the osmotically active intravesicular space. cl- itself, nitrate, hydroxyl, and sulfite could substitute for hco-3. the hco-3/cl- exchange pr ... | 1985 | 4061678 |
the effects of temperature, salinity and a simulated tidal cycle on the toxicity of fenitrothion to callinectes sapidus. | the 96 hr lc50 for callinectes sapidus exposed to fenitrothion at 22 degrees c and a salinity of 34 ppt (parts per thousand) was estimated to be 8.6 micrograms/l with a 95% confidence interval of 7.4-9.9 micrograms/l. acute toxicity was shown to increase with increasing temperature as well as increasing salinity. exposure of callinectes to a simulated tidal cycle of 17 ppt salinity change at 6 hr intervals increased the acute toxicity of fenitrothion to callinectes. the autotomization response i ... | 1985 | 2858335 |
method for measuring microbial degradation and mineralization of(14)c-labeled chitin obtained from the blue crab,callinectes sapidus. | a method for measuring microbial degradation and mineralization of radiolabeled native chitin is described.(14)c-labeled chitin was synthesized in vivo by injecting shed blue crabs (callinectes sapidus) with n-acetyl-d-[1-(14)c]-glucosamine and allowing for its incorporation into the exoskeleton. the cuticle had a total organic carbon content of 0.48 mg c mg(-1) with a specific radioactivity of 6,356 cpm mg(-1). glucosamine, i.e., chitin content as determined colorimetrically, was 22% (w/w). mic ... | 1985 | 24221359 |
nutritional availability to rats of selenium in four seafoods: crab (callinectes sapidus), oyster (crassostrea virginica), shrimp (penaeus duorarum) and baltic herring (clupea harengus). | 1. the present study was conducted to determine the biological availability to rats of the selenium in four high-se seafoods: crab (callinectes sapidus), oyster (crassostrea virginica), shrimp (penaeus duorarum) and baltic herring (clupea harengus). 2. weanling male rats were fed on a se-deficient torula yeast diet for 4 weeks followed by either continued depletion or repletion for 4 weeks with 0.05, 0.1 or 0.2 microgram se as selenite/g, or 0.1 or 0.2 microgram se as freeze-dried cooked test fo ... | 1986 | 3676154 |
responses to reversed nh3 and nh4+ gradients in a teleost (ictalurus punctatus), an elasmobranch (raja erinacea), and a crustacean (callinectes sapidus):evidence for nh4+/h+ exchange in the teleost and the elasmobranch. | ammonia excretion rates of channel catfish, ictalurus punctatus, little skate (raja erinacea), and blue crab (callinectes sapidus) were measured in experimental regimes which permitted simultaneous assessment of the partial pressure gradients for nonionized nh3 and the chemical concentration gradients of nh4+. under conditions of low external ammonia, the average ammonia excretion was +295 microm kg-1 h-1 for catfish, +149 microm kg-1 h-1 for blue crabs, and +59 microm kg-1 h1 for skates with pa ... | 1986 | 3746231 |
the uptake and in vivo metabolism of the organophosphate insecticide fenitrothion by the blue crab, callinectes sapidus. | callinectes were exposed to [14c]fenitrothion at a level of 5.2 micrograms/liter in either 22 degrees c, 34 ppt; 22 degrees c, 17 ppt; or 17 degrees c, 34 ppt seawater. uptake from the water, as measured by a decrease in fenitrothion, and the distribution of radioactivity throughout the callinectes were determined. the nature of radiolabeled metabolites in the water and hepatopancreas was also determined. fenitrothion was absorbed more rapidly from the water at the higher salinity and temperatur ... | 1986 | 3764904 |
colonization of the gut of the blue crab (callinectes sapidus) by vibrio cholerae. | attachment of vibrio cholerae to the mucosal surface of the intestine is considered to be an important virulence characteristic. vibrio cholerae, an autochthonous member of brackish water and estuarine bacterial communities, also attaches to crustacea, a significant factor in multiplication and survival of v. cholerae in nature. the ability of v. cholerae to attach to the gut wall of the blue crab (callinectes sapidus) was examined, and attachment was observed only in the hindgut and not the mid ... | 1986 | 3767362 |
heterogeneous humoral and hemocyte-associated lectins with n-acylaminosugar specificities from the blue crab, callinectes sapidus rathbun. | callinectes sapidus serum and hemocyte microsomal fraction agglutinated a panel of untreated and enzyme treated vertebrate erythrocytes and cultured lymphoid cell lines. crossed absorption experiments suggested the presence of multiple specific lectins in the serum. the microsomal fraction showed a 35-fold increase in specific activity when compared to the hemocyte lysate suggesting that hemocyte lectins are membrane-associated. agglutination by serum and hemocyte lectins was inhibited by low co ... | 1986 | 3769455 |
total mercury and its distribution in blue crab and deep water pink shrimp from alexandria coast. | total mercury content and its distribution in muscles and viscera of male and female blue crab (callinectes sapidus rothbum) and deep water pink shrimp (parapenacus longirostris) collected from the 3 main fishing grounds near the alexandria coast in the mediterranean sea was estimated. the results indicate that the mercury content in the muscles of both species differ according to fishing areas, size, sex, and species. more than 75% of total mercury were accumulated in the viscera of both specie ... | 1987 | 3696196 |
detection of protein variation in human serum by externally released precipitins from the blue crab, callinectes sapidus. | 1. a number of invertebrate species releases precipitins into the environment. this process is apparently part of an externally directed immunologic system. 2. a saline solution of precipitins released from the blue crab, callinectes sapidus, provided a reagent that produced two different precipitation reactions with proteins from the sera of human individuals. 3. one of the reaction variants was also detected with mammalian antiserum, the other was not. the former variant was associated with a ... | 1987 | 3427930 |
correlation between osmoregulation and cell volume regulation. | the euryhaline crab, callinectes sapidus, behaves both as an osmoregulator when equilibrated in salines in the range of 800 mosm and below and an osmoconformer when equilibrated in salines above 800 mosm. there exists a close correlation between osmoregulation seen in the whole animal in vivo and cell volume regulation studied in vitro. hyperregulation of the hemolymph osmotic pressure and cell volume regulation both occurred in salines at approximately 800 mosm and below. during long-term equil ... | 1987 | 3565606 |
the purification and characterization of glutathione s-transferase from the hepatopancreas of the blue crab, callinectes sapidus. | high glutathione s-transferase activity was found in the cytosol of f-cells from the hepatopancreas of the blue crab (callinectes sapidus). purification of glutathione s-transferase from hepatopancreas extracts by sephadex g-200, deae-sephacel, and chromatofocusing resulted in the isolation of two isozymes with isoelectric points of 5.9 and 5.7, as determined by analytical isoelectric focusing. using 1-chloro-2,4-dinitrobenzene as the substrate the specific activities of the two purified isozyme ... | 1987 | 3592675 |
the effect of dibutyryl camp on sodium uptake by isolated perfused gills of callinectes sapidus. | hemolymph, collected from 25 and 100% seawater acclimated callinectes sapidus and perfused through the isolated gill, causes increases in na+ uptake in the gill. similarly, dibutyryl camp causes increases in na+ uptake when perfused through the gill. since pericardial organ (po) extracts dopamine and octopamine are known to increase camp levels in the perfused gill, it is suggested that these substances from the po may be the hemolymph factors which increase na+ uptake via the mediation of camp ... | 1987 | 3028905 |
ammonium ion substitutes for k+ in atp-dependent na+ transport by basolateral membrane vesicles. | ion-transporting cells from posterior gills of blue crabs (callinectes sapidus) acclimated to low salinity were used as starting material for the preparation of microsomal membrane vesicles by density gradient centrifugation. the na+-k+-adenosinetriphosphatase (atpase)-enriched basolateral vesicles were loaded with kcl- or nh+4-containing medium by dilution and centrifugation, and initial rates of 22na+ uptake into the vesicles were measured by a rapid filtration procedure. varying the extravesi ... | 1987 | 3030142 |
quaternary ammonium sulfanilamide: a membrane-impermeant carbonic anhydrase inhibitor. | a novel carbonic anhydrase (ca) inhibitor, quaternary ammonium sulfanilamide (qas), was tested for potency as a ca inhibitor and for its ability to be excluded from permeating biological membranes. inhibitor titration plots of qas vs. pure bovine ca ii and ca from the gills of the blue crab, callinectes sapidus, yielded ki values of approximately 15 microm; thus qas is a relatively weak but effective ca inhibitor. permeability of the qas was directly tested by two independent methods. the inhibi ... | 1987 | 3107405 |
membrane-associated carbonic anhydrase in gills of the blue crab, callinectes sapidus. | the presence of the enzyme carbonic anhydrase (ca) on the basal membrane of the branchial endothelial cells in the blue crab and its physiological significance were studied in vivo using a membrane-impermeant ca inhibitor, quaternary ammonium sulfanilamide (qas). injection of qas into the hemolymph of callinectes sapidus resulted in the rapid development of a respiratory acidosis; pco2 rose almost 2 torr, ph was lowered by approximately 0.25 units, and total co2 rose by 2 mm. these results suppo ... | 1987 | 3107406 |
morphological and behavioral antipredatory adaptations of decapod zoeae. | zoeae of some species of estuarine decapods are retained in the estuary throughout development while others are exported into nearshore coastal waters. the horizontal migrations of decapod zoeae to coastal waters may have evolved to reduce the probability of encountering planktivorous fishes which are most abundant in the estuary. if so, then the morphological vulnerability of zoeae to fish predation should be inversely related to the number of predators occurring where they develop. six species ... | 1987 | 28311521 |
occurrence of trematodes in nerves of the blue crab, callinectes sapidus. | 1988 | 3373008 | |
comparative properties of channel catfish (ictalurus punctatus) and blue crab (callinectes sapidus) acetylcholinesterases. | 1. acetylcholinesterases (aches) from channel catfish and blue crabs were examined for substrate preference, kms, effects of inhibitors, and ph and osmotic activity profiles. 2. similarities were noted for substrate preference along with ph and osmotic optima. 3. crab ache had a lower km (9 x 10(-5) vs 2 x 10(-4) m) and was more sensitive in terms of ki50s than fish ache to eserine (2.6 x 10(-7) vs 3 x 10(-7) m), malathion (4.5 x 10(-5) vs 1.6 x 10(-4) m) and parathion (6.9 x 10(-5) vs 7 x 10(-4 ... | 1988 | 2905945 |
allostery in callinectes sapidus hemocyanin: cooperative oxygen binding and interactions with l-lactate, calcium, and protons. | allosteric interactions of callinectes sapidus hemocyanin have been investigated by generation of precision oxygen-binding curves using a modified imai apparatus and their subsequent analysis using numerical methods. the monod-wyman-changeux (mwc) model, the mwc model extended to include hybrid r3t3 states, and the phenomenological adair equation were fit to the experimental data. the hybrid mwc model provided a quantitatively better fit to the data than did the mwc model. the fits of the hybrid ... | 1988 | 2837279 |
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 |
purification and characterization of an iron-binding protein from the blue crab (callinectes sapidus). | the presence of an iron-binding protein in the hemolymph of the blue crab (callinectes sapidus) was detected by gel filtration of 59fe-labeled hemolymph. the iron-binding protein was purified to homogeneity by ion exchange chromatography. 2. this protein has a mol. wt of 155,000 and consists of a single polypeptide chain with an isoelectric point of 5.0. 3. analysis of the iron-loaded protein indicates that it has a high affinity for iron and the capacity to bind approximately 10 atoms iron/mole ... | 1990 | 2085965 |
blood glucose changes in the blue crab callinectes sapidus rathbun on transfer from sea water to air. | intertidal decapods regulate their blood glucose with a significant but transitory (60 min) increase upon exposure to atmospheric air, and this has been considered to be an adaptative response related to the almost complete lack of the pasteur effect in facultative anaerobes. in these animals we would not observe an increase in substrate availability to cope with the small amount of energy furnished by anaerobic pathways but rather a general metabolic depression. however, this hypothesis has nev ... | 1990 | 2094547 |
concurrent protein synthesis is required for in vivo chitin synthesis in postmolt blue crabs. | chitin synthesis in crustaceans involves the deposition of a protein-polysaccharide complex at the apical surface of epithelial cells which secrete the cuticle or exoskeleton. the present study involves an examination of in vivo incorporation of radiolabeled amino acids and amino sugars into the cuticle of postmolt blue crabs, callinectes sapidus. rates of incorporation of both 3h leucine and 3h threonine were linear with respect to time of incubation. incorporation of 3h threonine into the endo ... | 1990 | 2250160 |
cytokeratin and desmoplakin analogues within an intracellular parasite. | a significant amount of the total protein in the spore sacs of the microsporidian thelohania sp. consisted of the cytoskeletal elements, cytokeratin intermediate filaments, and the desmosomal analogues. the cytokeratin and desmosomal analogues were organized as cage envelopes surrounding the spores within the spore sac stage. thelohania sp. parasitizes the skeletal muscle of callinectes sapidus, a crustacean that does not appear to have cytokeratins or desmosomes. immunoprobe data indicate thelo ... | 1990 | 29314962 |
the identification and structure-activity relations of a cardioactive fmrfamide-related peptide from the blue crab callinectes sapidus. | the pericardial organs and thoracic ganglia of the blue crab callinectes sapidus were resected and extracted. the extracts were fractionated by hplc and the fractions analyzed by a radioimmunoassay (ria) to fmrfamide. multiple peaks of immunoreactivity were present and one of these, upon fast atom bombardment mass spectrometry (fab-ms) and microsequencing, yielded the sequence gynrsflrfamide. the amount of this peptide in each crab is between 7 and 13 pmol. several incomplete sequences were also ... | 1991 | 1815216 |
fishing a superfund site: dissonance and risk perception of environmental hazards by fishermen in puerto rico. | risk perception studies show that individuals tend to underestimate significant risks, overestimate negligible ones, and distrust authorities. they also rely on a variety of strategies or heuristics to reach decisions regarding their risk-taking behavior. we report on a survey of fishermen and crabbers engaged in recreational and substance fishing in a puerto rican estuary (near humacao), which has been declared a "superfund site" because of suspected contamination by mercury, and at ecologicall ... | 1991 | 1876726 |
shell disease and metal content of blue crabs, callinectes sapidus, from the albemarle-pamlico estuarine system, north carolina. | concentrations of 13 elements were determined for three tissues (gill, hepatopancreas, muscle) in diseased crabs from a contaminated estuary (pamlico river, nc), and in non-diseased crabs from both the contaminated estuary and a relatively uncontaminated area (albemarle sound, nc) during the fall 1989 and summer 1990. the diseased crabs had lesions which completely penetrated their dorsal integument, while the non-diseased crabs lacked lesions. sediments within the contaminated area showed enric ... | 1992 | 1456781 |
novel protein inhibits in vitro precipitation of calcium carbonate. | organic molecules both coexist and interact with inorganic crystal lattices in biomineralizing tissues. mineral precipitation and crystal morphology are tightly regulated by the actions of these molecules. polyacrylamide gel electrophoresis studies on water soluble extracts from the cuticle of callinectes sapidus (atlantic blue crab) reveal the presence, in unmineralized nascent premolt cuticle, of proteins which are absent in the mineralized postmolt cuticle. in the present studies, homogenates ... | 1992 | 1497356 |
metal-specific induction of metallothionein isoforms in the blue crab callinectes sapidus in response to single- and mixed-metal exposure. | metallothioneins (mts) play an important role in the metabolism of copper and zinc during the molt cycle of the blue crab. in this study we examined the hypothesis that mt expression in crabs is metal specific. anion-exchange chromatography showed one major zncumt (znmt-i) in control crabs, two mt isoforms in cadmium-treated crabs (cdmt-i, cdmt-ii), and three forms (cumt-i, cumt-ii, cumt-iii) in copper-treated animals. amino acid analysis of the carboxymethylated apo-mts, purified by reversed-ph ... | 1992 | 1567201 |
principal component analysis, trace elements, and blue crab shell disease. | 1992 | 1590588 | |
calcitonin-like immunoreactivity in the blue crab: tissue distribution, variations in the molt cycle, and partial characterization. | calcitonin-like immunoreactivity has been found in blood and tissues of the marine blue crab, callinectes sapidus rathbun. the activity in blood rises significantly during the immediate premolt (d4) stage, but tissue immunoreactivity does not vary significantly with molt stage. the immunoreactivity to antisalmon calcitonin serum is due to a 27.2 kda protein that shows strong similarities in amino acid composition to a similar protein in a lobster and to human calcitonin precursor. the protein is ... | 1992 | 1640198 |
in vivo magnetic resonance imaging of the blue crab, callinectes sapidus: effect of cadmium accumulation in tissues on proton relaxation properties. | nuclear magnetic resonance imaging (mri) has been used to visualize the internal anatomy of a living blue crab. the resolution obtained in these studies was sufficient to distinguish individual organs by the differences in their proton densities and proton relaxation properties. t1 (spin-lattice relaxation time)-weighted imaging revealed the lipid-rich nature of the hepatopancreas and gonadal tissue. to evaluate the effect of metal-induced stress on the different organs, crabs were exposed to el ... | 1992 | 1645119 |
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 |
the impact of limb autotomy on mate competition in blue crabs callinectes sapidus rathbun. | this study is the first to demonstrate experimentally that autotomy (self-amputation of a body part) adversely affects competition for mates. experiments were conducted using blue crabs callinectes sapidus rathbun to examine the consequences of limb loss and pairing precedence on mate acquisition by males. two adult males of equivalent size were introduced sequentially into pools containing a sexually-receptive female and observed after 24 h and 48 h. one male in each pair was left intact, while ... | 1992 | 28311879 |
mercury bioaccumulation in organisms from three puerto rican estuaries. | we analyzed mercury levels in shrimp (palaemonetes sp.), blue crabs (callinectes sp.), fish (tarpon megalops atlantica and tilapia tilapia mossambica), lizards (ameiva exsul), cattle egret (bubulcus ibis) and moorhen (gallinula chloropus) in three estuaries in puerto rico in 1988. there were no quantifiable concentrations greater than the method detection limit of mercury in shrimp, crabs and lizards from any site. mercury levels were also below detection limits in tilapia, except for specimens ... | 1992 | 24226951 |
trace elements and organochlorines in the shoalgrass community of the lower laguna madre, texas. | our objectives were to measure concentrations of seven trace elements and 14 organochlorine compounds in sediment and biota of the shoalgrass (halodule wrightii) community of the lower laguna madre of south texas and to determine whether chemicals associated with agriculture (e.g. mercury, arsenic, selenium, organochlorine pesticides) were highest near agricultural drainages. arsenic, mercury, selenium, lead, cadmium, and organochlorines were generally at background concentrations throughout the ... | 1993 | 24225804 |
coarse woody debris as a refuge from predation in aquatic communities : an experimental test. | this study demonstrates experimentally that coarse woody debris (cwd) can provide refuge from predation in aquatic habitats. in the rhode river subestuary of chesapeake bay, maryland, (usa), we (1) measured the abundance of cwd, (2) examined the utilization of cwd by mobile epibenthic fish and crustaceans, and (3) tested experimentally the value of cwd as a refuge from predation. cwd was the dominant above-bottom physical structure in shallow water, ranging in size from small branches (<2 cm dia ... | 1993 | 28313814 |
induction of metallothionein mrna in the blue crab (callinectes sapidus) after treatment with cadmium. | 1. dietary treatment of blue crabs with cadmium led to an increase of cadmium metallothionein in the hepatopancreas. 2. utilizing a unique purification procedure, poly a+ rna was isolated from the hepatopancreas of control and cadmium-treated blue crabs with 260/280 nm ratios of 2.0 or better. 3. poly a+ rna was hybridized with a series of oligonucleotide probes derived from a portion of the amino acid sequence of lobster metallothionein. a single band of approx. 300 base pairs was present in co ... | 1993 | 8098685 |
a putative glutathione-binding site in cdzn-metallothionein identified by equilibrium binding and molecular-modelling studies. | glutathione (gsh) has been found to form a complex with both vertebrate and invertebrate copper-metallothionein (cumt) [freedman, ciriolo and peisach (1989) j. biol. chem. 264, 5598-5605; brouwer and brouwer-hoexum (1991) arch. biochem. biophys. 290, 207-213]. in this paper we report on the interaction of gsh with cdznmt-i and cdznmt-ii from rabbit liver and with cdmt-i from blue crab hepatopancreas. ultrafiltration experiments showed that all three mts combined with gsh. the measured binding da ... | 1993 | 8363576 |
depolarization-activated potentiation of the t fiber synapse in the blue crab. | the blue crab t fiber synapse, associated with the stretch receptor of the swimming leg, has a nonspiking presynaptic element that mediates tonic transmission. this synapse was isolated and a voltage clamp circuit was used to control the membrane potential at the release sites. the dependence of transmitter release on extracellular calcium, [ca]o, was studied over a range of 2.5-40 mm. a power relationship of 2.7 was obtained between excitatory postsynaptic potential (epsp) rate of rise and [ca] ... | 1993 | 8382259 |
hemocyanin synthesis in the blue crab callinectes sapidus. | 1. the synthesis of hemocyanin in the blue crab, callinectes sapidus, was investigated by molecular techniques. 2. polyadenylated mrna was prepared from the hepatopancreas and translated in rabbit reticulocyte lysate. 3. translation products were immunoprecipitated with immobilized antihemocyanin igg. analysis of the igg-bound polypeptides by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed two polypeptides comigrating with authentic callinectes hemocyanin. 4. a synthetic degener ... | 1993 | 8448995 |
isolation of antho-rfamide related peptides from the eyestalks of blue crab. | 1. two carboxyl-terminally amidated peptides (cp1 and cp2) were isolated from the blue crab (callinectes sapidus) eyestalks by a method of carboxyl-terminal analysis. 2. the peptides were sequenced as pglu-gly-arg-phe-amide (cp1) and pglu-leu-gly-arg-phe-amide (cp2). 3. each carboxyl-terminus of the peptides was precisely determined by amino acid analysis utilizing phenylisothiocyanate derivatives. 4. cp1 was identical to the sea anemone neuropeptide, antho-rfamide. | 1993 | 8462277 |
enterotoxigenic escherichia coli and staphylococcus aureus in fish and seafood from the southern region of brazil. | an investigation to evaluate the microbiological condition and safety of fish and seafood commonly harvested at the coast of santa catarina state and sold in florianópolis was undertaken. one hundred and seventy-five samples of fish and fish fillets (cynoscion leiarchus), shrimp tails (peneaus paulensis), shellfish-meat (anomalocardia brasiliensis and metilus edulis), and crab-meat (callinectes sapidus) were collected from markets and examined within 4 h of purchase. for isolation and enumeratio ... | 1994 | 7703011 |
hemolymph lectins of the blue crab, callinectes sapidus, recognize selected serotypes of its pathogen vibrio parahaemolyticus. | 1994 | 8192339 | |
effect of the external concentration of calcium on the postmoult uptake of calcium in blue crabs (callinectes sapidus) | the rate of calcium uptake in blue crabs (callinectes sapidus rathbun) acclimated to 2 sea water with a calcium concentration of 1.4 mmol l-1 was dependent on the magnitude and direction of the electrochemical gradient for calcium. when transferred to water with a high calcium concentration (6 mmol l-1), the electrochemical gradient for calcium favoured diffusive influx, and calcium uptake and apparent h+ excretion increased by approximately 50 %. when transferred to water with a low calcium con ... | 1994 | 9317209 |
mechanism of the net uptake of water in moulting blue crabs (callinectes sapidus) acclimated to high and low salinities | blue crabs (callinectes sapidus rathbun) acclimated to a salinity of 2 approximately doubled in wet mass (excluding carapace) during the period from 10 h before moult to 2 h after moult. both in blue crabs acclimated to 2 salinity and in crabs acclimated to 28 salinity, the drinking rate increased from approximately 0.4 ml 100 g-1 h-1 at 1 day prior to moult to approximately 8 ml 100 g-1 h-1 during the first hour after moult. the drinking rate had decreased 1 day after moult in both salinities, ... | 1994 | 9317238 |
post-exercise lactate production and metabolism in three species of aquatic and terrestrial decapod crustaceans | aquatic and terrestrial crustaceans are dependent on both aerobic and anaerobic metabolism for energy production during exercise. anaerobic energy production is marked by an accumulation of lactate in both muscle tissue and haemolymph, but the metabolic fate of lactate is not clear. lactate recycling via gluconeogenesis and the potential role of carbonic anhydrase (ca) in supplying bicarbonate for the carboxylation of pyruvate were investigated in three species of decapod crustaceans: callinecte ... | 1994 | 9317667 |
distribution and characterization of angiotensin-converting enzyme-like activity in tissues of the blue crab callinectes sapidus. | angiotensin-converting enzyme-like activity (acela) was determined in tissue homogenates of the blue crab, callinectes sapidus, using the synthetic substrate hippuryl-histidyl-leucine (hip-his-leu) and the specific inhibitor, captopril. acela was highest in gill homogenates followed by the hepatopancreas and hemolymph with specific activities of 1.69, 0.37 and 0.10 nmol/min/mg protein, respectively. gill enzyme activity was membrane-associated and no difference in activity was noted between ante ... | 1994 | 7915656 |
evaluation of lactic acid bacterium fermentation products and food-grade chemicals to control listeria monocytogenes in blue crab (callinectes sapidus) meat. | fresh blue crab (callinectes sapidus) meat was obtained from retail markets in florida and sampled for viable listeria monocytogenes. the pathogen was found in crabmeat in three of four different lots tested by enrichment and at levels of 75 cfu/g in one of the same four lots by direct plating. next, crabmeat was steam sterilized, inoculated with a three-strain mixture of l. monocytogenes (ca. 5.5 log10 cfu/g), washed with various lactic acid bacterium fermentation products (2,000 to 20,000 arbi ... | 1994 | 7944362 |
subunit composition of hemocyanins of callinectes sapidus: phenotypes from naturally hypoxic waters and isolated oligomers. | the electrophoretic banding pattern of hemocyanin monomers in blue crabs caught in natural waters indicate that the phenotypes associated with normoxia or hypoxia in the laboratory can also be found in those conditions in nature. page of pure fractions of 1 x 6-mers isolated by hplc revealed only the two invariant plus one slightly variable band. in contrast, the 2 x 6-mer fraction contained those three plus the three highly variable bands. these results support the hypothesis formulated by earl ... | 1994 | 7953073 |
molecular cloning of two pigment-dispersing hormone (pdh) precursors in the blue crab callinectes sapidus reveals a novel member of the pdh neuropeptide family. | a cdna library was established from the eyestalk ganglia of the blue crab callinectes sapidus. screening resulted in the isolation of a clone (497 bp excluding poly(a) tail) which encodes a beta-pdh previously found in several crustacean species. it displays high sequence similarity with a clone isolated from an eyestalk cdna library of the shore crab carcinus maenas, indicating the close phylogenetic relationship of both species. a second clone (414 bp exclusive of the poly(a) tail) encodes a n ... | 1994 | 7999056 |
crab: snail size-structured interactions and salt marsh predation gradients. | we studied size-structured predator-prey interactions between blue crabs (callinectes sapidus) and marsh periwinkles (littoraria irrorata) with a combination of field studies, laboratory experiments and individual-based modeling. size distributions of littoraria differed among years at the same sites in a salt marsh and could largely be explained by dominance of strong cohorts in the population. at a given site, abundance increased with elevation above tidal datum. size-selective predation by bl ... | 1994 | 28313589 |
a comparison of the gill physiology of two euryhaline crab species, callinectes sapidus and callinectes similis: energy production, transport-related enzymes and osmoregulation as a function of acclimation salinity | callinectes sapidus and c. similis co-occur in estuarine waters above 15 salinity. callinectes sapidus also inhabits more dilute waters, but c. similis is rarely found below 15 . previous work suggests that c. sapidus may be a better hyperosmoregulator than c. similis. in this study, energy metabolism and the levels of transport-related enzymes in excised gills were used as indicators of adaptation to low salinity. oxygen consumption rates and mitochondrial cytochrome content of excised gills in ... | 1995 | 9317943 |
three-dimensional solution structure of callinectes sapidus metallothionein-1 determined by homonuclear and heteronuclear magnetic resonance spectroscopy. | metallothionein is a cysteine-rich metal-binding protein whose biosynthesis is closely regulated by the level of exposure of an organism to zinc, copper, cadmium, and other metal salts. the metallothionein from callinectes sapidus is known to bind six divalent metal ions in two separate metal-binding clusters. heteronuclear 1h-113cd and homonuclear 1h-1h nmr correlation experiments have been used to establish that the two clusters reside in two distinct protein domains. the three-dimensional sol ... | 1995 | 7819257 |
primary structure and tissue-specific expression of blue crab (callinectes sapidus) metallothionein isoforms. | in aquatic animals, synthesis of the metal-binding protein metallothionein (mt) can be induced through exposure to elevated levels of metals in food or water. whether the different routes of exposure lead to expression of different metallothionein isoforms in different tissues in unknown. in this study we examined the induction of metallothionein isoforms in the hepatopancreas and gills of the blue crab callinectes sapidus. when blue crabs are exposed to cadmium in their diet, the metal accumula ... | 1995 | 7487904 |
molecular cloning of a cdna encoding putative molt-inhibiting hormone from the blue crab, callinectes sapidus. | a cdna library was constructed using poly(a+) rna isolated from eyestalk neural ganglia of the blue crab, callinectes sapidus. the library was screened using a probe generated by pcr based on the published amino acid sequence of molt-inhibiting hormone from the shore crab, carcinus maenas. dna sequence analysis of one positive clone revealed a 339 bp open reading frame encoding a 78-residue putative molt-inhibiting hormone and a 35-residue signal peptide. the deduced amino acid sequence of c. sa ... | 1995 | 7537497 |
a highly conserved red pigment-concentrating hormone precursor in the blue crab callinectes sapidus. | a cdna library was established from the eyestalk ganglia of the blue crab callinectes sapidus. one clone was isolated (644 bp excluding the poly(a) tail) which encodes the red pigment-concentrating hormone (rpch)-precursor, consisting of the 25 amino acid residue signal peptide, the rpch, and a 73 amino acid residue rpch-precursor related peptide. this clone displays high sequence similarity with a clone isolated from an eyestalk cdna library of the shore crab carcinus maenas, in accordance with ... | 1995 | 7611999 |
coordination and neuromuscular control of rhythmic behaviors in the blue crab, callinectes sapidus. | the stereotypical courtship display (cd) behavior of the male blue crab, callinectes sapidus, includes an unusual component: the rhythmic waving of the swimming appendages above the carapace. this behavior occurs in a unique context but it resembles two other rhythmic behaviors performed using the swimming legs: sideways swimming and backward swimming. as a first step to understanding the mechanisms that allow the expression of apparently different rhythmic motor patterns, we have examined these ... | 1995 | 7643320 |
modulation of behavior by biogenic amines and peptides in the blue crab, callinectes sapidus. | using the blue crab callinectes sapidus as a model system, we have investigated the effects of potential neuromodulators on freely behaving animals. of interest is the modulatory effect of a number of drugs on three rhythmic behaviors of the blue crab: courtship display (cd) of the male crab, sideways swimming and backward swimming. the drugs tested were proctolin, dopamine, octopamine, serotonin, and norepinephrine. injection of each drug elicited a unique posture or combination of limb movemen ... | 1995 | 7643321 |
neuromodulation of rhythmic motor patterns in the blue crab callinectes sapidus by amines and the peptide proctolin. | the blue crab callinectes sapidus, provides an opportunity to study neuromodulation of three variations of rhythmic behavior produced by the same appendages. these behaviors are sideways swimming, backward swimming and courtship display (cd). each behavior has a different context, and despite similarities among them, each is quantifiably distinguishable. cd behavior occurs in males, is stimulated naturally by pheromone, and elements of the behavior are evoked by proctolin and dopamine. sideways ... | 1995 | 7643322 |
atrial natriuretic peptide gene expression within invertebrate hearts. | the present investigation was designed to (1) determine if atrial natriuretic factor gene expression occurs within invertebrates as well as within vertebrates; (2) determine whether the product of this gene expression is the 126-amino-acid atrial natriuretic factor prohormone or some other molecular species; and (3) evaluate within the same invertebrates if the products of atrial natriuretic factor gene expression are released into their circulation. utilizing a very sensitive rnase protection a ... | 1995 | 8575660 |
a comparison of calcium binding in callinectes sapidus premolt and postmolt cuticle homogenates: implications for regulation of biomineralization. | cuticle tissue homogenates (cths) from callinectes sapidus premolt cuticle bound approximately 367% more ca2+ ions than did those from the postmolt cuticle. the ph-stat assay which was used to compare in vitro caco3 nucleation times confirmed that the premolt cths had greater inhibitory activity than did the postmolt cths. this inhibitory activity was indicated by caco3 nucleation times in excess of control values. premolt nucleation times exceeded those of postmolt samples by approximately 340% ... | 1995 | 8747426 |
antimicrobial susceptibility and plasmid-mediated streptomycin resistance of plesiomonas shigelloides isolated from blue crab. | five plesiomonas shigelloides strains isolated from retail or wild-catch louisiana blue crabs (callinectes sapidus) were examined for resistance to selected antibiotics and presence of plasmids. three agar media, macconkey, salmonella-shigella and a modification of inositol brilliant green bile salt (ibb), were evaluated for isolation of p. shigelloides. of these, ibb was most satisfactory for distinguishing between p. shigelloides and the related species aeromonas hydrophila. isolates were susc ... | 1996 | 8760329 |
distribution of dopamine-like immunoreactivity suggests a role for dopamine in the courtship display behavior of the blue crab, callinectes sapidus. | injection of dopamine initiates a posture in the blue crab, callinectes sapidus, identical to courtship display behavior of the male crab. the threshold for proctolin-induced rhythmic components of courtship display is lowered in preparations when dopamine is co-applied with proctolin. to elucidate the anatomical substrate of this behavior, immunocytochemistry was used to map dopamine-immunoreactive neurons. courtship display is sex-specific, and dependent on the hormonal, developmental, and sea ... | 1996 | 8766168 |
phylogeny of the haplosporidia (eukaryota: alveolata) based on small subunit ribosomal rna gene sequence. | the phylogenetic position of the phylum haplosporidia was investigated with the complete small subunit rrna gene sequences from 5 species in the phylum: haplosporidium nelsoni and haplosporidium costale, parasites of the eastern oyster crassostrea virginica; haplosporidium louisiana, a parasite of the mudcrab panopeus herbstii; minchinia teredinis, a parasite of shipworms (teredo spp.) and urosporidium crescens, a hyperparasite found in metacercariae of the trematode megalophallus sp. in the blu ... | 1996 | 8691370 |
proctolinlike immunoreactivity and identified neurosecretory cells as putative substrates for modulation of courtship display behavior in the blue crab, callinectes sapidus. | pheromonally stimulated courtship display (cd) behavior in male blue crabs (callinectes sapidus) is characterized by rhythmic waving of the fifth legs. the waving of the fifth legs is modulated by proctolin in freely moving crabs and in reduced preparations. to begin to identify an anatomical substrate for cd behavior we have localized putative proctolinergic cells and described the morphology of neurosecretory neurons known to oscillate during pheromonal stimulation of reduced preparations. pro ... | 1996 | 8725299 |
complete primary structure of the molt-inhibiting hormone (mih) of the mexican crayfish procambarus bouvieri (ortmann). | the amino acid sequence of mih was elucidated by means of digestions with specific proteases, manual edman degradation, and mass spectrometry. mih consists of a 72-residue peptide chain (molecular mass 8322 da) with six cysteines forming three disulfide bridges that connect residues 7-43, 23-39, and 26-52. it has blocked n- and c-termini and lacks tryptophan, histidine, and methionine. mih shows striking similarity to the crustacean hyperglycemic hormone (chh) isomorphs of procambarus bouvieri ( ... | 1996 | 8735961 |
risk of clostridium botulinum type e toxin production in blue crab meat packaged in four commercial-type containers. | the aim of this investigation was to determine if a risk of clostridium botulinum growth and toxin production existed in four different packaged crabmeat products. freshly picked blue crab meat was inoculated with 10(3) to 10(4) spores per g of a mixed pool of four strains of c. botulinum type e (beluga, minnesota, g21-5, and 070). the lump crabmeat was packaged in four different packaging containers: (i) 12-oz copolymer polyethylene cups currently used by most crab processors; (ii) 12-oz copoly ... | 1996 | 10463443 |
quality characteristics of fresh blue crab meat held at 0 and 4 degrees c in tamper-evident containers. | there has been a regulatory movement toward the required use of tamper-evident containers for fresh blue crab meat. north carolina passed tamper-evident regulations in 1993. blue crab processors had little information on possible changes in head-space gases, microbial growth, chemical decomposition, sensory quality, or shelf life caused by the new containers. chemical, microbiological, physical, and sensory changes in fresh crab meat were monitored during 18 days of storage in ice and 13 days of ... | 1996 | 10463450 |
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 |
perireceptor mechanisms sustaining olfaction at low salinities: insight from the euryhaline blue crab callinectes sapidus | as the blue crab callinectes sapidus moves from sea water to fresh water, the 'exposed' chemosensory dendrites in the olfactory sensilla (aesthetascs) undergo changes in length that are positively correlated with environmental salinity. in this study, we demonstrate the following. (1) the responses of the olfactory receptor cells of freshwater-acclimated crabs are reduced relative to those of seawater-acclimated animals, but increase with a time course comparable to the increase in dendrite leng ... | 1997 | 9318098 |