| an in vitro culture system for crayfish organs. | organs of crayfishes--mainly integument of astacus leptodactylus--have been kept in an in vitro culture of several days. the medium consists of 2 parts of van harreveld saline and one part of horse serum, supplemented with antibiotics for long term cultures. this medium is very similar to the astacus hemolymph in its ionic content, the ph, the osmolarity, the protein concentration and the cholesterol content. the glucose concentration is somewhat higher and there are differences in the nitrogen ... | 1979 | 94722 |
| complete amino acid sequence of the sarcoplasmic calcium-binding protein (scp-i) from crayfish (astacus leptodactylus). | the complete amino acid sequence of the alpha chain of the dimeric sarcoplasmic ca2+-binding protein (scp-i = alpha 2) from crayfish (astacus leptodactylus) has been determined by partial automatic sequencing of the peptides derived from tryptic digests of the protein after citraconylation or treatment with 1,2-cyclohexanedione. overlapping peptides were obtained by cleavage with o-iodosobenzoic acid, or digestion with staphylococcus aureus protease, thermolysin and pepsin. the acetylated n-term ... | 1989 | 2917647 |
| protein methylase ii in five taxa from three phyla. | protein methylase ii (protein o-methyltransferase, ec 2.1.1.24) was found in dictyostelium discoideum amoebae, astacus leptodactylus axonal, locusta migratoroides neuronal, torpedo marmorata electroplaque and bos bovis stratial tissue and compared in both the soluble and particulate fractions. the intrinsic decay data of the methyl groups transferred onto proteins from dictyostelium and torpedo tissues were virtually identical. the short term kinetics of the methyl group transfer of all fraction ... | 1987 | 3030627 |
| emulsifiers in the intestinal juice of crustacea. isolation and nature of surface-active substances from astacus leptodactylus esch. and homarus vulgaris l. | | 1973 | 4719995 |
| [the effect on blood coagulation of the trypsin-like protease from astacus leptodactylus (crustacea)]. | | 1970 | 5426215 |
| trace elements in crayfish: regional differences and changes induced by cooking. | the concentrations of pb, cd, zn, cu, ni, cr, mn, co, as, and se were determined in the abdominal muscle and hepatopancreas from raw and cooked crayfish of astacus astacus (l.) and pacifastacus leniusculus (dana), both of swedish origin. after cooking, the concentrations of cd, ni, and co in the hepatopancreas showed a decrease and the concentrations of pb, cu, and mn in the abdominal muscle showed an increase. metal and metalloid concentrations were also determined in the abdominal muscle and h ... | 1994 | 8311505 |
| sequence analysis of the ribosomal internal transcribed spacer dna of the crayfish parasite psorospermium haeckeli. | two morphotypes of the crayfish parasite psorospermium haeckeli were isolated from 2 crayfish species of different geographical origin. the oval-shaped sporocysts were obtained from the epidermal and connective tissue beneath the carapace of the noble crayfish astacus astacus from sweden and finland. elongated spores were isolated from the abdominal muscle tissue of the red swamp crayfish procambarus clarkii from usa. to compare genetic divergence of 2 morphotypes of the parasite, the ribosomal ... | 2001 | 11710556 |
| an antibody to recombinant crustacean hyperglycaemic hormone of nephrops norvegicus cross-reacts with neuroendocrine organs of several taxa of malacostracan crustacea. | the crustacean hyperglycaemic hormones (chhs) are multifunctional neuropeptides that play a central role in the physiology of crustaceans. a partial cdna coding for chh of the norway lobster, nephrops norvegicus, was cloned; this cdna was fused to glutathione- s-transferase (gst) to obtain a recombinant fusion protein that was used to raise a rabbit antiserum and to perform a biological assay. the specificity of the purified antibody was demonstrated by means of western blotting. to validate the ... | 2002 | 11845331 |
| the environmental consequences of alien species in the swedish lakes mälaren, hjälmaren, vänern and vättern. | twenty alien species have become established in the lakes mälaren, vänern, vättern and hjälmaren. intentional introductions include fish and the signal crayfish from north america, ornamental plants, and the canada goose. unintentional introductions include the crayfish plague introduced with infected crayfish, the zebra mussel, and chinese mitten crab introduced with ballast water. the introduction of pathogens and parasites, in particular the crayfish plague, to the lakes has had the greatest ... | 2001 | 11878025 |
| detection of genomic dna of the crayfish plague fungus aphanomyces astaci (oomycete) in clinical samples by pcr. | a diagnostic procedure, based on a polymerase chain reaction method (pcr) was developed to detect infection of crayfish with the oomycete aphanomyces astaci. a set of oligonucleotide primers was designed to specifically amplify a. astaci dna in the its region surrounding the 5.8s rdna gene. the pcr amplifies a 115bp amplicon. the specificity of the primers was demonstrated by testing on 27 a. astaci strains and against 20 non-a. astaci oomycetes and 5 fungal species. most of the non-a. astaci oo ... | 2004 | 15145505 |
| gene-expression profiling of white spot syndrome virus in vivo. | white spot syndrome virus, type species of the genus whispovirus in the family nimaviridae, is a large, double-stranded dna (dsdna) virus that infects crustaceans. the genome of the completely sequenced isolate wssv-th encodes 184 putative open reading frames (orfs), the functions of which are largely unknown. to study the transcription of these orfs, a dna microarray was constructed, containing probes corresponding to nearly all putative wssv-th orfs. transcripts of 79 % of these orfs could be ... | 2005 | 15958687 |
| na(+)/k(+)-atpase activity and immunocytochemical labeling in podobranchial filament and lamina of the freshwater crayfish astacus leptodactylus eschscholtz: evidence for the existence of sodium transport in the filaments. | in the crayfish astacus leptodactylus, the podobranch, bearing respiratory and ion-transporting filaments, is attached to the lamina. the na(+)/k(+)-atpase activity is higher in filaments than in lamina. using a mouse monoclonal antibody directed against the alpha subunit of na(+)/k(+)-atpase, and indirect immunofluorescence microscopy, we can observe that the immunoreactivity of the antibody is different for each kind of structure. the lamina presents an ion-transporting type epithelium, which ... | 1999 | 18627870 |
| endocrine effects of contaminated sediments on the freshwater snail potamopyrgus antipodarum in vivo and in the cell bioassays in vitro. | lake pilnok located in the black coal-mining region ostrava-karvina, czech republic, contains sediments highly contaminated with powdered waste coal. moreover, population of the endangered species of narrow-clawed crayfish pontastacus leptodactylus with high proportion of intersex individuals (18%) was observed at this site. these findings motivated our work that aimed to evaluate contamination, endocrine disruptive potency using in vitro assays and in vivo effects of contaminated sediments on r ... | 2008 | 18675471 |
| concentration of heavy metals in different tissues of astacus leptodactylus from aras dam of iran. | due to different human activities in the vicinities of aras dam, various pollutants such as heavy metals are entered into the reservoir and thus polluting the aquatic ecosystem. as a result, this heavy metal is accumulated in the tissues of astacus leptodoctylus, which is considered as one the abundant species of crayfish that has got important food values and is of economic importance due to its export to other countries. in this research, the bioaccumulation of heavy metals in different tissue ... | 2007 | 19090263 |
| total metal levels in crayfish astacus leptodactylus (eschscholtz, 1823), and surface sediments in lake terkos, turkey. | the aim of this study was to determine the total metal accumulation (aluminium, copper, manganese, lead, cadmium and iron) in different organs and eggs of astacus leptodactylus (eschscholtz, 1823) and sediments total metal contents (aluminium, copper, manganese, lead, cadmium, iron, zinc, chromium, nickel) in lake terkos. water and sediment samples were collected from two stations at two different depths (1 and 2 m) of lake terkos in may 2008. crayfish samples were collected by trammel net at th ... | 2010 | 19847663 |
| the effects of pollution on the vitamins a, e, c, beta-carotene contents and oxidative stress of the freshwater crayfish, astacus leptodactylus. | in this study, we determined the effects of pollution on levels of antioxidant vitamins (a, e, c), beta-carotene and malondialdehyde (mda), in the hepatopancreas and muscle tissues of freshwater crayfish (astacus leptodactylus). the crayfish samples were collected from aydincik (unpolluted control site) and ağin (polluted site) in the keban dam lake (elazig-turkey) in august 2007. the results showed that the concentrations of vitamins e, c and beta-carotene in both tissues were significantly low ... | 2010 | 19853916 |
| detection and quantification of the crayfish plague agent in natural waters: direct monitoring approach for aquatic environments. | aphanomyces astaci, a specialised parasite of north american freshwater crayfish, is the disease agent of crayfish plague that is lethal to european freshwater crayfish. the life cycle of a. astaci has been inferred from experimental laboratory studies, but less is known about its natural sustainability and ecology. to address such questions, tools for monitoring of a. astaci directly in aquatic environments are needed. here, we present an approach for detecting and quantifying a. astaci directl ... | 2011 | 21797031 |
| potent infection reservoir of crayfish plague now permanently established in norway. | noble crayfish astacus astacus is threatened in europe due to invasive crayfish carrying the crayfish plague agent aphanomyces astaci. norway is among the last countries in which the introduction of non-indigenous crayfish has been limited through strict legislation practices. however, north american signal crayfish pacifastacus leniusculus were recently discovered in a water-course that has been repeatedly hit by the plague. we mapped the distribution and relative density (catch per unit effort ... | 2011 | 22235597 |
| differing virulence of aphanomyces astaci isolates and elevated resistance of noble crayfish astacus astacus against crayfish plague. | crayfish plague epidemics (caused by aphanomyces astaci) have been causing population collapses among native european crayfish stocks since the late 1800s. recent indirect and direct evidence has shown that its virulence has been variable, with native european crayfish even acting as carriers. we tested the differences in a. astaci virulence under experimental conditions using both psi- and as-genotypes with 3 finnish noble crayfish astacus astacus populations. we infected crayfish with adjusted ... | 2012 | 23269387 |
| fast atom bombardment mass spectra of various peptides from sarcoplasmic calcium-binding protein. | the sarcoplasmic calcium-binding protein of the crayfish astacus leptodactylus is a calciprotein. the primary structure of this protein has been determined. tryptic digestion of the denaturated protein followed by high-performance liquid chromatographic separation identified essentially eight peptides. the structure of these peptides has been confirmed after amino acid analysis by fast atom bombardment spectra in positive mode. | 2011 | 3242705 |
| aspects of ionic transport mechanisms in crayfish astacus leptodactylus. | | 2012 | 4412095 |
| effects of some ca2+ blockers on receptor potentials of crayfish retina. | one drug known to inactivate calmodulin and two others to block ca2+ channels were applied to isolated superfused retinae of the crayfish astacus leptodactylus and their influence on the receptor potentials (rp) was studied. trifluoperazine causes an increase of the amplitude of maximum (h max) of rp and a prolongation of the time of half decrease (t2). furthermore, trifluoperazine could antagonise the effect of raised calcium concentration of superfusate, which decreases h max and shortens t2 o ... | 2013 | 3764406 |
| identification of nonecdysteroid steroids in hemolymph of both male and female astacus leptodactylus (crustacea) by gas chromatography-mass spectrometry. | the o-pentafluorobenzyloxime (opfb)-heptafluorobutyrylester (hfb) derivatives of hemolymph steroid extracts from both male and female astacus leptodactylus were subjected to negative ion chemical ionization and capillary gas chromatography-mass spectrometry (nci/gc-ms). five nonecdysteroid steroids, namely pregnenolone, 17 alpha-hydroxypregnenolone, testosterone, cholesterol, and 6 beta-hydroxyprogesterone were identified. with selected ion monitoring (sim), indications were found for the presen ... | 2010 | 2937682 |
| effects of synbiotics on immunity and disease resistance of narrow-clawed crayfish, astacus leptodactylus leptodactylus (eschscholtz, 1823). | the aim of this study was to evaluate the effects of prebiotics (mannanoligosaccharide and xylooligosaccharide), probiotics (enterococcus faecalis and pediococcus acidilactici) and synbiotics for 126 days on the immune responses, hemolymph indices, antioxidant enzymes, and biological responses after a 48-hour aeromonas hydrophila exposure of sub-adult crayfish (11.45 ± 1.87 g). most antibacterial activities were observed in the shell mucus of crayfish fed a diet containing xylooligosaccharide + ... | 2017 | 28363588 |
| fusarium avenaceum causes burn spot disease syndrome in noble crayfish (astacus astacus). | burn spot disease has been causing epidemics both in the estonian mainland and in saaremaa island in the threatened noble crayfish (astacus astacus) stocks. to study the cause of the disease, we isolated several fusarium spp. from estonian noble crayfish (a. astacus) populations suffering from burn spot disease syndrome. we first identified fungi directly from melanised cuticle by their its sequences. then we isolated fusarium spp. from melanised spots of crayfish showing burn spot disease sympt ... | 2013 | 23557716 |
| recovery of hafnia alvei from diseased brown trout, salmo trutta l., and healthy noble crayfish, astacus astacus (l.), in bulgaria. | hafnia alvei was isolated in bulgaria from healthy noble crayfish, astacus astacus (l.), and then from farmed diseased brown trout, salmo trutta l., with signs of haemorrhagic septicaemia. the isolates were identified initially with conventional phenotyping and commercial merlin micronaut and api 20e rapid identification systems, followed by sequencing of the 16s rrna gene. hafnia alvei bt1, bt2 and aa4 were of low virulence to rainbow trout and brown trout, although cytotoxicity was demonstrate ... | 2014 | 24422558 |
| [ecological and radio-ecological effects from long-term use of the lake kyzyl-tash as a cooling reservoir by the nuclear fuel cycle facility]. | this review introduces long-term study findings on ecological and radiation induced regime of the water reservoir - lake kyzyl-tash (r-2) - used as a heat sink of nuclear-power reactors in the southern urals from 1948 through 2008. it was exhibited that water reservoir exploitation by the nuclear fuel cycle facility "mayak" pa resulted in hydrological, thermal, hydrochemical and radiological ecosystem regimes changes. the central radioactive substances depot in the water reservoir was determined ... | 2016 | 20968056 |
| toxic and heavy metals as a cause of crayfish mass mortality from acidified headwater streams. | mining activities are responsible for high concentrations of metals in river networks in many parts of the world. mining activities and the resulting high loads of heavy metals interact with intensive acid rain, and often have great consequences for biodiversity. however, considering the frequently episodic nature of these heavy acid rains, there is little detailed evidence of direct impacts. in 2011 we observed a massive mortality of noble crayfish and stone crayfish in padrťsko special area of ... | 2017 | 28108890 |
| high-resolution structural and elemental analyses of calcium storage structures synthesized by the noble crayfish astacus astacus. | during premolt, crayfish develop deposits of calcium ions, called gastroliths, in their stomach wall. the stored calcium is used for the calcification of parts of the skeleton regularly renewed for allowing growth. structural and molecular analyses of gastroliths have been primarily performed on three crayfish species, orconectes virilis, procambarus clarkii, and more recently, cherax quadricarinatus. we have performed high-resolution analyses of gastroliths from the native noble crayfish, astac ... | 2016 | 27612582 |
| de novo assembly and annotation of the freshwater crayfish astacus astacus transcriptome. | we generated rna-seq data to assemble the transcriptome of the noble crayfish (astacus astacus) from four combined tissues (abdominal muscle, hepatopancreas, ovaries, green glands). a total of 194 million read pairs with a length of 100 bp were generated. the transcriptome was assembled de novo using trinity software, producing 158,649 non-redundant transcripts. lowly expressed transcripts were filtered out leaving 45,415 transcripts of which 14,559 were found to contain open reading frames with ... | 2016 | 26988698 |
| prevalence of the pathogen aphanomyces astaci in freshwater crayfish populations in croatia. | the oomycete aphanomyces astaci is an obligate crayfish parasite that co-evolved with american crayfish species, and they therefore generally live in a balanced relationship. on the contrary, european native crayfish are highly susceptible to a. astaci, and infestation with it causes development of the lethal disease termed crayfish plague. until now, 5 a. astaci strains have been described from the freshwater crayfish present in europe. in this study we aimed to investigate the occurrence of th ... | 2016 | 26865234 |
| subcellular localization of calcium deposits in the noble crayfish astacus astacus spermatophore: implications for post-mating spermatophore hardening and spermatozoon maturation. | the freshly ejaculated spermatophore of crayfish undergoes a hardening process during post-mating storage on the body surface of female. the ultrastructural distribution of calcium deposits were studied and compared in freshly ejaculated and post-mating noble crayfish spermatophores, using the oxalate-pyroantimonate technique, to determine possible roles of calcium in post-mating spermatophore hardening and spermatozoon maturation. small particles of sparsely distributed calcium deposits were vi ... | 2016 | 26817519 |
| effect of experimental exposure to differently virulent aphanomyces astaci strains on the immune response of the noble crayfish astacus astacus. | european crayfish are sensitive to the crayfish plague pathogen, aphanomyces astaci, carried by north american crayfish species due to their less effective immune defence mechanisms against this disease. during a controlled infection experiment with a susceptible crayfish species astacus astacus using three a. astaci strains (representing genotype groups a, b, and e), we investigated variation in their virulence and in crayfish immune defence indicators (haemocyte density, phenoloxidase activity ... | 2015 | 26410255 |
| founder event and its effect on genetic variation in translocated populations of noble crayfish (astacus astacus). | establishing translocated populations is a common process to preserve and maintain genetic diversity of threatened species. in 2001, three translocated populations of noble crayfish (astacus astacus) were established in the czech republic, founded by either adult or juvenile individuals from three particular source populations. we assessed genetic diversity at seven microsatellite loci after one decade (assumed three generations) from establishment. although the translocated populations exhibite ... | 2016 | 26077200 |
| label-free protein quantification in freshly ejaculated versus post-mating spermatophores of the noble crayfish astacus astacus. | crayfish spermatophores are deposited on the body surface of the female during mating and remain there for a period of time before fertilization ensues. post-mating changes in protein expression level in the noble crayfish astacus astacus spermatophore were quantified. in-gel digestion and high resolution mass spectrometry were used for label-free protein quantification. one hundred twelve proteins were identified in the spermatophore of noble crayfish. after 7 days of storage on the body of the ... | 2015 | 25871631 |
| ultrastructure of egg activation and cortical reaction in the noble crayfish astacus astacus. | morphological changes in the gamete of female noble crayfish at four developmental stages were studied. mature ovarian oocytes are enclosed by the first envelope that consists of two layers. numerous pores are visible on the surface of the outer layer of this envelope and the inner layer contains bottlebrush-shaped objects. three types of vesicles, including some that are highly and moderately electron-dense and some multi-layered, occur in the cortex of the oocyte. in freshly ovulated eggs, the ... | 2015 | 25464149 |
| molecular detection and genotyping of aphanomyces astaci directly from preserved crayfish samples uncovers the norwegian crayfish plague disease history. | aphanomyces astaci causes crayfish plague in european freshwater crayfish, but most historical epizootics lack agent isolation and identification. although declared as crayfish plague outbreaks by the norwegian competent authorities, only presumptive diagnoses without agent isolation exist from norwegian epizootics until 2005. molecular methods now allow both a. astaci detection and genotype determination from preserved samples. we therefore aimed to (1) investigate molecularly if a. astaci was ... | 2014 | 25124447 |
| dose-dependent mortality of the noble crayfish (astacus astacus) to different strains of the crayfish plague (aphanomyces astaci). | several reports of the european crayfish species carrying a latent infection of the crayfish plague (aphanomyces astaci) have emerged and the discussion has focused especially on the lowered virulence of as-genotypes behind decreased mortality. the aim of this study was to compare the killing rate of different a. astaci strains in controlled infection experiments. two separate infection experiments with three a. astaci strains (ueft2b (as), evira6462/06 (as) and uef8866-2 (psi)) were made to com ... | 2014 | 24184185 |
| lunar-rhythmic molting in laboratory populations of the noble crayfish astacus astacus (crustacea, astacidea): an experimental analysis. | juvenile noble crayfish, astacusastacus (crustacea, astacidea) in the second year of age were kept in the laboratory for a twelve-month period under continuing "summer conditions" (ld 16:8, 19°c). molting processes in this population could be synchronized by artificial moonlight cycles. peaks of exuviations occurred at "new moons". males showed a slightly higher degree of synchronization than females. a phase-shift of the artificial lunar cycle in relation to the natural cycle resulted in a corr ... | 2013 | 23840899 |
| distribution and epidemiology of genotypes of the crayfish plague agent aphanomyces astaci from noble crayfish astacus astacus in finland. | the crayfish plague agent aphanomyces astaci was isolated from 69 noble crayfish astacus astacus samples in finland between 1996 and 2006. all isolates were genotyped using randomly amplified polymorphic dna-polymerase chain reaction (rapd-pcr). altogether, 43 isolates belonged to the genotype group of astacus strains (as), which is assumed to represent the genotype originally introduced into europe around 1860 and into finland in 1893. there were 26 crayfish plague isolates belonging to the gro ... | 2013 | 23574706 |
| effects of climate change, invasive species, and disease on the distribution of native european crayfishes. | climate change will require species to adapt to new conditions or follow preferred climates to higher latitudes or elevations, but many dispersal-limited freshwater species may be unable to move due to barriers imposed by watershed boundaries. in addition, invasive nonnative species may expand into new regions under future climate conditions and contribute to the decline of native species. we evaluated future distributions for the threatened european crayfish fauna in response to climate change, ... | 2013 | 23531056 |
| comparative ultrastructure of the spermatozoa of three crayfish species: austropotamobius torrentium, pacifastacus leniusculus, and astacus astacus (decapoda: astacidae). | this study reports about the spermatozoal ultrastructure of three species of astacid crayfish, i.e., the stone crayfish austropotamobius torrentium, signal crayfish pacifastacus leniusculus, and noble crayfish astacus astacus. the acrosome is a cup shaped and electron-dense structure at the anterior of the spermatozoon and comprises three layers of differing electron densities filled with parallel filaments that extend from the base to the apical zone. the acrosome was significantly longer in a. ... | 2013 | 23475696 |
| temporal dynamics of spore release of the crayfish plague pathogen from its natural host, american spiny-cheek crayfish (orconectes limosus), evaluated by transmission experiments. | the crayfish plague pathogen, aphanomyces astaci, is one of the most serious threats to indigenous european crayfish species. the north american invasive spiny-cheek crayfish, orconectes limosus, is an important source of this pathogen in central and western europe. we evaluated potential changes in a. astaci spore release rate from infected individuals of this species by experiments investigating the pathogen transmission to susceptible noble crayfish, astacus astacus. we filtered defined volum ... | 2013 | 23425502 |
| timing and quantifying aphanomyces astaci sporulation from the noble crayfish suffering from the crayfish plague. | aphanomyces astaci sporulation is crucial for the spreading potential of this disease agent. for the first time, we are reporting timing and quantity of a. astaci spores released from noble crayfish (astacus astacus) suffering from crayfish plague under practical aquatic conditions. we infected nine noble crayfish with a. astaci psi-genotype and maintained them in individual 8l tanks. spores (zoospores and cysts) were quantified from water samples (3 × 1 ml) taken every 12h over 10 d using a. as ... | 2013 | 23102971 |
| incomes, attitudes, and occurrences of invasive species: an application to signal crayfish in sweden. | this article analyzes and carries out an econometric test of the explanatory power of economic and attitude variables for occurrences of the nonnative signal crayfish in swedish waters. signal crayfish are a carrier of plague which threatens the native noble crayfish with extinction. crayfish are associated with recreational and cultural traditions in sweden, which may run against environmental preferences for preserving native species. econometric analysis is carried out using panel data at the ... | 2009 | 18946699 |
| isolation and characterization of 11 novel microsatellite dna markers in the noble crayfish, astacus astacus. | | 2009 | 18786153 |
| a large discoidal lipoprotein present in only one of two closely related crayfish. | the hemolymph lipoproteins of two european freshwater crayfish, astacus astacus and astacus leptodactylus, were isolated and characterized. the former species possesses two sex-independent lipoproteins, which can be related to the formerly described high-density lipoprotein (hdl)/beta-glucan binding protein and very high-density lipoprotein/clotting protein from other crustaceans. the latter species, however, contains an additional third lipoprotein with a unique structure. it is a large discoid ... | 2008 | 18415110 |
| the concentrations of antioxidant compounds in the hepatopancreas, the gills and muscle of some freshwater crayfish species. | we examined the concentrations of vitamin e (vit e), sulphydryl groups (-sh), total protein and protein electrophoretic profiles in the hepatopancreas, the gills and muscle of three freshwater crayfish species: noble crayfish (astacus astacus), stone crayfish (austropotamobius torrentium) and spiny cheek crayfish (orconectes limosus). vit e concentration in the hepatopancreas of o. limosus was lower compared to a. astacus, while in the gills of o. limosus it was lower compared to both a. astacus ... | 2006 | 17278707 |
| the influence of dietary antioxidant on ovarian eggs and levels of vitamin e, c, a, astaxanthin, β-carotene and oxidative stres in tissues of astacus leptodactylus (eschscholtz) during reproduction. | the experiment was conducted to determine the most effective antioxidant (among the vitamin e (ve), vitamin c (vc), vitamin a (va), astaxanthine (ax), β-carotene (βc)) on the ovarian egg number and size, level of ve, vc, va, ax, βc and oxidative stress (as malondialdehyde (mda)) in the hepatopancreas, ovarian, gills and muscle tissue during ovarian development of astacus leptodactylus. one control (c) and five experimental diets (ee, ec, ea, eax and eβc) were prepared. the ee, ec, ea, eax and eβ ... | 2016 | 28145851 |
| oxidative stress and some biochemical parameters during starvation and refeeding in astacus leptodactylus (esch., 1823). | this study was conducted to determine the effect of starvation (78 days) and refeeding (33 days) on oxidative stress (malondialdehyde (mda)), antioxidants (superoxide dismutase (sod), catalase (cat), glutathione reductase (gr), glutathione peroxidase (gsh-px)), arginase (ar) and nitric oxide (no) in the hepatopancreas, muscle and gills tissues of freshwater crayfish (astacus leptodactylus). crayfish were maintained at three experimental groups: control (fed), starved (not fed) crayfish for 78 d ... | 2016 | 28040060 |
| the sublethal effects of (2,4-dichlorophenoxy) acetic acid (2,4-d) on narrow-clawed crayfish (astacus leptodactylus eschscholtz, 1823). | 2,4-d is a widely used phenoxy herbicide, potentially toxic to humans and biota. the objective of the present study was to reveal short term sublethal effects of 2,4-d on narrow-clawed freshwater crayfish (astacus leptodactylus eschscholtz, 1823), based on histology, total haemocyte counts, selected haemolymph parameters, and oxidative stress parameters. in the laboratory conditions crayfish specimens were exposed to 9 mg l-1 of 2,4-d for one week. experiments were conducted under semi-static co ... | 2016 | 28033103 |
| genetic va riation in the na rrow-c lawed c ra yfish (astacus lepto dactylus) po pulatio ns as assesse d by pcr-rflp of mitochondria l coi gene. | the genetic variation and population structure of narrow-clawed crayfish (astacus leptodactylus) was examined by means of polymerase chain reaction (pc r) restriction fragment length polymorphism (rf lp) analysis of the cytochrome oxidase subunit i (coi) of mitochondrial dna. a total of 194 adult specimens were collected from seven sample sites including, two in the south caspian sea and one each in anzali wetland and aras reservoir and three rivers chafrood, masule rudkhan and s iah darvishan. ... | 2015 | 27844014 |
| crayfish chitosan for microencapsulation of coriander (coriandrum sativum l.) essential oil. | in this study, chitosan, which was obtained from the waste shells of crayfish (astacus leptodactylus), was used for the encapsulation of the essential oil isolated from coriander (coriandrum sativum l.) via the spray drying method. the obtained capsules were characterized using sem, ft-ir, tga and xrd. the size of the microcapsules was between 400nm - 7μm. it was determined that the swelling characteristic of the capsules was ph sensitive. the release showed bi-phasic characteristics and the max ... | 2016 | 27341783 |
| synthesis and characterization of new chitosan-based schiff base compounds. | chitin (cn) was extracted from the armors of crustaceans astacus leptodactylus (lake sevan, armenia) and then converted to chitosan (cs), its deacetylated derivative. novel schiff bases (cssb) were synthesized by interaction of cs with 4-(2-chloroethyl)benzaldehyde (aldehyde-1) and 4-(2-bromoethyl)benzaldehyde (aldehyde-2), and underwent dehydrohalogenation, under basic conditions (10°c), to yield respective vinyl derivatives. all newly synthesized compounds were structurally characterized by so ... | 2016 | 27106149 |
| a novel approach to the measurement of surfactant parameters in arthropod digestive juices. | in arthropods, the determination of two important parameters of digestive juices, i.e. the total surfactant concentration and the critical micelle concentration (cmc), is challenging due to small sample volumes and low surfactant concentrations. in this work, we report a successful implementation of potentiometric titrations using the surfactant ion-selective electrode (sise) and the pyrene fluorescence method (pfm) for the determination of the total surfactant concentration and cmc in the diges ... | 2016 | 26969560 |
| morphology and ultrastructure of the somatic cells in astacus leptodactylus ovary. | we defined the somatic environment in which female germinal cells develop, and performed ultrastructural analyses of various somatic cell types, with particular reference to muscle cells and follicle cells, that reside within the ovary at different stages of oogenesis. our findings show that ovarian wall of the crayfish is composed of long muscle cells, blood cells, blood vessels and hemal sinuses. the follicle and germinal cells lie within a common compartment of ovarian follicles that is defin ... | 2016 | 26453477 |
| plasticity in fecundity highlights the females' importance in the spiny-cheek crayfish invasion mechanism. | invasion is one of the most consequential phenomena affecting the distribution of native species. few in number of species, european crayfish are losing the competition with introduced north american crayfish. the spiny-cheek crayfish, orconectes limosus, is an outstanding example, successfully competing against the native narrow-clawed crayfish, astacus leptodactylus. for four years, we collected data regarding crayfish occurrences, their relative abundance, and the structure of populations in ... | 2015 | 26358988 |
| one precursor, three apolipoproteins: the relationship between two crustacean lipoproteins, the large discoidal lipoprotein and the high density lipoprotein/β-glucan binding protein. | the novel discoidal lipoprotein (dlp) recently detected in the crayfish, differs from other crustacean lipoproteins in its large size, apoprotein composition and high lipid binding capacity, we identified the dlp sequence by transcriptome analyses of the hepatopancreas and mass spectrometry. further de novo assembly of the ngs data followed by blast searches using the sequence of the high density lipoprotein/1-glucan binding protein (hdl-bgbp) of astacus leptodactylus as query revealed a putativ ... | 2014 | 25281909 |
| biochemical response of crayfish astacus leptodactylus exposed to textile wastewater treated by indigenous white rot fungus coriolus versicolor. | the discharge of textile effluents into the environment without appropriate treatment poses a serious threat for the aquatic organisms. the present study was undertaken to investigate biochemical response of crayfish astacus leptodactylus exposed to textile wastewater (tw) treated by indigenous white rot fungus coriolus versicolor. glutathione s-transferase (gst), cytochrome p450 1a1 (cyp1a1), and acetylcholinesterase (ache) levels in hepatopancreas and abdomen tissues of crayfish exposed to unt ... | 2015 | 25226834 |
| population structure and genetic analysis of narrow-clawed crayfish (astacus leptodactylus) populations in turkey. | the genetic differentiation among turkish populations of the narrow-clawed crayfish was investigated using a partial sequence of cytochrome oxidase subunit i gene (585 bp) of 183 specimens from 17 different crayfish populations. median joining network and all phylogenetic analyses disclosed a strong haplotype structure with three prominent clades diverged by a range between 20 and 50 mutations and substantial inter-group pairwise sequence divergence (5.19-6.95 %), suggesting the presence of thre ... | 2014 | 25139434 |
| post-mating morphological changes in the spermatozoon and spermatophore wall of the crayfish astacus leptodactylus: insight into a non-motile spermatozoon. | morphology of the crayfish spermatozoon and of the spermatophore wall during three stages of final maturation including freshly ejaculated, post-mating, and after spermatozoa release was studied and compared. the crayfish spermatophore consists of a sperm mass enveloped by a three layered spermatophore wall. after mating, the thickness of the outer layer of the spermatophore is increased. the matrix in the middle layer of the spermatophore becomes reticulated, and granules inside this layer rele ... | 2014 | 25115806 |
| investigation of chloramine-t impact on crayfish astacus leptodactylus (esch., 1823) cardiac activity. | the crayfish play an essential role in the biomonitoring and may reflect ambient water quality through the biochemical, behavioural and physiological reactions. to assess whether narrow-clawed crayfish astacus leptodactylus can respond by heart rate changes to presence in water of such biocide as chloramine-t, adult males were exposed to its low (2 and 5 mg l(-1)), moderate (10 mg l(-1), commonly used in industry and aquaculture) and exceeded (20 and 50 mg l(-1)) concentrations. in addition, a p ... | 2014 | 24819440 |
| temporal changes in concentrations of some trace elements in muscle tissue of crayfish, astacus leptodactylus (eschscholtz, 1823), from keban dam lake. | crayfish (astacus leptodactylus eschscholtz, 1823) is the native crayfish species in turkey. it was exported regularly to western europe. in this study, bioaccumulation and temporal trends of some trace elements (arsenic: as, cadmium: cd, copper: cu, mercury: hg, lead: pb, and zinc: zn) in edible abdomen muscle of crayfish from keban dam lake (elazığ, turkey) were investigated for the 2006-2012 period. sequence of metal concentration levels was zn > cu > hg > pb > cd > as in muscle tissues. the ... | 2014 | 24707241 |
| the influence of etofenprox on narrow clawed crayfish (astacus leptodactylus eschscholtz, 1823): acute toxicity and sublethal effects on histology, hemolymph parameters, and total hemocyte counts. | the acute and sublethal effects of etofenprox, a nonester pyrethroid, was determined in narrow-clawed crayfish (astacus leptodactylus eschscholtz, 1823). semistatic bioassay procedures were followed in both experiments, and the 24, 48, 72, and 96 h lc50 values (with 95% confidence limits) of technical etofenprox for crayfish were calculated as 0.68, 0.61, 0.45, and 0.41 µg/l, respectively based on finney's probit analysis. two concentrations of etofenprox (0.04 and 0.1 µg/l) were tested to deter ... | 2015 | 24510384 |
| [a change of the medium salinity as a functional load for evaluation of physiological state of the crayfish astacus leptodactylus]. | the necessity of developing criteria for evaluation of the functional state of benthic invertebrates for toxicological studies or for their use as biosensors in systems of the water quality biomonitoring is emphasized. it is proposed to evaluate the organism state with aid of standard test actions dosed by strength and duration. for freshwater crayfish, such action--the functional load--can be the medium salinity change by 1%o, which can be achieved by addition of sodium chloride. peculiarities ... | 2014 | 25507788 |
| [a change of the medium salinity as a functional load for evaluation of physiological state of the crayfish astacus leptodactylus]. | the necessity of developing criteria for evaluation of the functional state of benthic invertebrates for toxicological studies or for their use as biosensors in systems of the water quality biomonitoring is emphasized. it is proposed to evaluate the organism state with aid of standard test actions dosed by strength and duration. for freshwater crayfish, such action--the functional load--can be the medium salinity change by 1%o, which can be achieved by addition of sodium chloride. peculiarities ... | 2014 | 25434190 |
| differential regulation of hexameric and dodecameric hemocyanin from a. leptodactylus. | the oxygen binding properties of hemocyanins are regulated on a short time scale by effectors such as l-lactate, urate and protons, and on longer time scales by expression of the different types of subunits. for astacus leptodactylus it was shown previously that acclimation to higher temperatures leads to increased levels of a 6-meric hemocyanin species, whereas at lower temperatures the 12-meric form prevails. here we show that the temperature dependence of the two forms supports the idea, that ... | 2013 | 23473954 |
| differences in the accumulation and distribution profile of heavy metals and metalloid between male and female crayfish (astacus leptodactylus). | concentrations of selected heavy metals and a metalloid were measured by icp-ms in crayfish (astacus leptodactylus) collected from lake hirfanli, turkey. aluminum (al), chromium ((52)cr, (53)cr), copper ((63)cu, (65)cu), manganese (mn), nickel (ni) and arsenic (as) were measured in the exoskeleton, gills, hepatopancreas and abdominal muscle tissues of 60 crayfish of both genders. with the exception of al, differences were determined between male and female cohorts for the accumulation trends of ... | 2013 | 23417157 |
| tissue distribution and correlation profiles of heavy-metal accumulation in the freshwater crayfish astacus leptodactylus. | the present work details the analysis of heavy-metal and metalloid concentrations in exoskeleton, gill, hepatopancreas, and abdominal muscle tissues of 60 crayfish (astacus leptodactylus) specimens collected from lake hirfanlı, a dam lake located in kırşehir (turkey) with a low metal-contamination profile. concentrations of 11 metals (aluminum [al], chromium [cd], manganese [mn], cobalt [co], nickel [ni], copper [cu], molybdenum [mo], silver [ag], cadmium [cd], mercury [hg], and lead [pb]) and a ... | 2013 | 23329359 |
| pcr detection of the crayfish plague pathogen in narrow-clawed crayfish inhabiting lake eğirdir in turkey. | many populations of the narrow-clawed crayfish astacus leptodactylus in turkey, including those inhabiting lake eğirdir, declined drastically in the mid-1980s due to introduction of crayfish plague aphanomyces astaci. however, unlike many other localities, there has been some recovery in the a. leptodactylus population inhabiting this lake even though crayfish plague has been suspected to have persisted since then. in support of this, dna from 5 of 34 healthy-looking crayfish sampled recently fr ... | 2012 | 22535876 |
| invasive crayfish and crayfish plague on the move: first detection of the plague agent aphanomyces astaci in the romanian danube. | native european crayfish, such as astacus leptodactylus, are threatened, among other factors, by the crayfish plague agent aphanomyces astaci, dispersed by invasive north american crayfish. two of these invaders, pacifastacus leniusculus and orconectes limosus, have extended their distribution in the river danube catchment; the latter was detected for the first time in romania in 2008. we monitored, at monthly intervals for over 2 yr, occurrence of native a. leptodactylus and invasive o. limosus ... | 2012 | 22422132 |
| fatty acid, cholesterol and fat-soluble vitamin composition of wild and captive freshwater crayfish (astacus leptodactylus). | the proximate analysis (dry matter, protein, fat and ash), cholesterol, fatty acid and fat-soluble vitamin compositions of the tail muscle of wild caught and captive crayfish (astacus leptodactylus) were investigated. captive crayfish contained higher moisture and fat content than wild crayfish. in contrast, wild crayfish contained a higher level of crude protein, ash and n-3 polyunsaturated fatty acids (pufa), particularly eicosapentaenoic (epa) and docosahexaenoic acid (dha) than captive crayf ... | 2012 | 22328124 |
| natural and synthetic chiral isoforms of crustacean hyperglycemic hormone from the crayfish astacus leptodactylus: hyperglycemic activity and hemolymphatic clearance. | in the crayfish astacus leptodactylus, as in several crustacean species, the crustacean hyperglycemic hormone is present as two isoforms differing by the chirality of the third residue, a phenylalanine. in the present work, isoforms synthesized full length by solid-phase peptide synthesis have been purified, refolded, the location of the disulfide bridges has been checked, their immunoreactivity against different antibodies have been analyzed and their hyperglycemic activity tested, to ensure th ... | 2012 | 22314080 |
| novel protocol for the chemical synthesis of crustacean hyperglycemic hormone analogues--an efficient experimental tool for studying their functions. | the crustacean hyperglycemic hormone (chh) is present in many decapods in different isoforms, whose specific biological functions are still poorly understood. here we report on the first chemical synthesis of three distinct isoforms of the chh of astacus leptodactylus carried out by solid phase peptide synthesis coupled to native chemical ligation. the synthetic 72 amino acid long peptide amides, containing l- or d-phe³ and (glp¹, d-phe³) were tested for their biological activity by means of hom ... | 2012 | 22253873 |
| genotoxicity monitoring of freshwater environments using caged crayfish (astacus leptodactylus). | genotoxicity of freshwater pollution was assessed by measuring dna damage in haemocytes of caged freshwater crayfish astacus leptodactylus by the means of comet assay and micronucleus test, integrated with the measurements of physiological (total protein concentration) and immunological (total haemocyte count) haemolymph parameters as biomarkers of undergone stress. crayfish were collected at the reference site (river mrežnica) and exposed in cages for 1 week at three polluted sites along the sa ... | 2012 | 22178377 |
| [dynamics of glucocorticoids in the ontogenesis of freshwater crawfish astacus leptodactylus esch]. | dynamics of changes in glucocorticoid (hydrocortisone and corticosterone) levels was studied in the ontogenesis of freshwater crawfish astacus leptodactylus esch. it was shown that steroid concentrations increase during the embryogenesis period. decrease in the glucocorticoid levels during postembryonic development is most probably related to the stabilization of young fish growth and the attainment of hormone levels typical for adult individuals. the correlation ofglucocorticoid levels with phy ... | 2013 | 21786658 |
| [glio-neuronal and glio-glial syncytial cytoplasmic connections in peripheral nerve trunks of the crayfish astacus leptodactylus]. | the paper considers various aspects of glial sheaths of neuritis in the crayfish peripheral nerve trunks and roots. there are revealed dotted glio-neurite tight junctions and a varicose deformation of the intercellular glio-neurite cleft. rupture of membranes in the area of contact leads to formation of the glio-neurite pore (less than 10 nm) that is enlarged and forms wide (up to 240 nm) syncytial perforations. at the edge of perforation, either remnants of tight junctions are present or damage ... | 2010 | 21061654 |
| the acute toxicity of fenitrothion on narrow-clawed crayfish (astacus leptodactylus eschscholtz, 1823) in association with biomarkers of lipid peroxidation. | the aim of this research was to evaluate the acute toxicity of fenitrothion to the crayfish (astacus leptodactylus eschscholtz, 1823), which is chosen as an alternative aquatic organism to fish by using the static test system and evaluate the basic lipid peroxidation parameters for the first 24 h. crayfish of 27.3 ± 0.56 g mean weight and 10.0 ± 0.72 cm mean length were selected for the bioassay experiments. the experiments were repeated three times in 20 liters of tap water. the temperature of ... | 2015 | 20957683 |
| genotoxic, physiological and immunological effects caused by temperature increase, air exposure or food deprivation in freshwater crayfish astacus leptodactylus. | the aim of this research was to investigate influence of different environmental stressors, such as temperature increase, air exposure and food deprivation on dna integrity of a bioindicator species, freshwater crayfish astacus leptodactylus. dna damage was measured in crayfish haemocytes using comet assay and micronucleus test. crayfish haemolymph was subsequentially sampled during their 7 days of exposure to increased temperatures (25 and 30 degrees c) and during 24 h of air exposure. both gro ... | 2010 | 20667483 |
| characterization of a membrane-bound angiotensin-converting enzyme isoform in crayfish testis and evidence for its release into the seminal fluid. | in the present study, an isoform of angiotensin-converting enzyme was characterized from the testis of a decapod crustacean, the crayfish astacus leptodactylus. angiotensin-converting enzyme cdna, obtained by 3'- to 5' race of testis rnas, codes for a predicted one-domain protein similar to the mammalian germinal isoform of angiotensin-converting enzyme. all amino acid residues involved in enzyme activity are highly conserved, and a potential c-terminus transmembrane anchor may be predicted from ... | 2009 | 19656189 |
| functional aspects of chh c-terminal amidation in crayfish species. | the crustacean hyperglycemic hormone is the most abundant neuropeptide present in the eyestalk of crustacea and its main role is to control the glucose level in the hemolymph. our study was aimed at assessing the importance of c-terminal amidation for its biological activity. two recombinant peptides were produced, asl-rchh-gly with a free carboxyl terminus and asl-rchh-amide with an amidated c-terminus. homologous bioassays performed on the astacid crayfish astacus leptodactylus showed that the ... | 2008 | 18281112 |
| bioaccumulation of lead nitrate in freshwater crayfish (astacus leptodactylus) tissues under aquaculture conditions. | the aim of this research was to evaluate the amount of lead in the tissue of astacus leptodactylus especially in their muscle which the consumed part of their body. in this study the crayfish was exposed to intermediate concentration of lead nitrate (500 microg l(-1)) for periods up to 3 weeks. in the first, second and third weeks bioaccumulation in various tissues was under investigation. the data of toxicological analysis obtained by the method of atomic absorption revealed that the levels of ... | 2007 | 19090138 |
| evidence for an angiotensin-converting enzyme (ace) polymorphism in the crayfish astacus leptodactylus. | the present study was initiated to characterize angiotensin-converting enzyme (ace) in crustaceans. using degenerate dna primers deduced from consensus sequences located upward and downward from the active site of aces from different arthropod species, several tissues from the crayfish astacus leptodactylus were screened by rt-pcr. amplicons were obtained from hepatopancreas, testis and hemocytes. analysis of the predicted protein sequences after cloning and northern blot experiments revealed an ... | 2007 | 17628211 |
| expression of na(+)/k(+)-atpase alpha-subunit mrna during embryonic development of the crayfish astacus leptodactylus. | astacus leptodactylus is a decapod crustacean fully adapted to freshwater where it spends its entire life cycle after hatching under huge osmoconcentration differences between the hemolymph and surrounding freshwater. we investigated the expression of mrna encoding one ion transport-related protein, na(+)/k(+)-atpase alpha-subunit, and one putative housekeeping gene, beta-actin, during crayfish ontogenesis using quantitative real-time pcr. a 216-amino acid part of the open reading frame region o ... | 2007 | 20483286 |
| freshwater crayfish astacus leptodactylus (eschscholtz, 1823) accumulates and depurates copper. | cu accumulation and depuration in various tissues of the crayfish astacus leptodactylus was investigated. adult specimens were exposed to 0.5, 2.5 and 5.0 mg cu/l under static conditions for three weeks. at the end of the 3rd week the specimens were divided into three groups and left in dechlorinated water for either 1, 2 or 3 weeks for depuration. after 7, 14 and 21 days, four crayfish from each group were instantaneously sacrificed. all crayfish were dissected into their hepatopancreas, gill, ... | 2007 | 17286170 |
| ultrastructural and functional characterization of circulating hemocytes from the freshwater crayfish astacus leptodactylus: cell types and their role after in vivo artificial non-self challenge. | the freshwater crayfish astacus leptodactylus (eschscholtz, 1823) is an important aquacultured decapod species as well as an invasive species in some european countries. in the current investigation we characterized the different classes of circulating blood cells in a. leptodactylus by means of light and electron microscopy analysis and we explored their reaction to different latex beads particles in vivo by total and differential cell counts at 0.5, 1, 2 and 4h after injections. we identified ... | 2007 | 16839768 |
| molecular characterization of the sarcoplasmic calcium-binding protein (scp) from crayfish procambarus clarkii. | sarcoplasmic calcium-binding protein (scp) is believed to function as the invertebrate equivalent of vertebrate parvalbumin, namely to "buffer" cytosolic ca2+. we have cloned and characterized a novel scp from axial abdominal muscle of crayfish procambarus clarkii (referred to as pcscp1), and have examined tissue specific distribution and expression as a function of molting stage in non-epithelial and epithelial tissues. the complete sequence of pcscp1 consists of 1,052 bp with a 579 bp open rea ... | 2006 | 16807031 |
| structure and function relationship in the abdominal stretch receptor organs of the crayfish. | the structure/function relationship in the rapidly and slowly adapting stretch receptor organs of the crayfish (astacus leptodactylus) was investigated using confocal microscopy and neuronal modeling methods. both receptor muscles were single muscle fibers with structural properties closely related to the function of the receptors. dendrites of the rapidly adapting neuron terminated in a common pile of nerve endings going in all directions. dendrites of the slowly adapting neuron terminated in a ... | 2005 | 15973677 |
| immunolocalization of na+,k+-atpase in the branchial cavity during the early development of the crayfish astacus leptodactylus (crustacea, decapoda). | the ontogeny of osmoregulation was examined in the branchial cavity of embryonic and early post-embryonic stages of the crayfish astacus leptodactylus maintained in freshwater, at the sub-cellular level through the detection of the sodium-potassium adenosine triphosphatase (na(+),k(+)-atpase). the embryonic rate of development was calculated according to the eye index (ei) which was 430-450 microm at hatching. the distribution of the enzyme was identified by immunofluorescence microscopy using a ... | 2005 | 15592941 |
| species-specific effects on hemolymph glucose control by serotonin, dopamine, and l-enkephalin and their inhibitors in squilla mantis and astacus leptodactylus (crustacea). | hemolymph glucose level is controlled by crustacean hyperglycemic hormone (chh) released from the eyestalk neuroendocrine centers under conditions of both physiological and environmental stress. biogenic amines and enkephalin have been found to mediate the release of several neurohormones from crustacean neuroendocrine tissue. we investigated the effect of serotonin, dopamine, and leucine-enkephalin in vivo--injected into the stomatopod squilla mantis and the decapod astacus leptodactylus--wheth ... | 2004 | 15559934 |
| ontogeny of the antennal glands in the crayfish astacus leptodactylus (crustacea, decapoda): immunolocalization of na+,k+-atpase. | the involvement of the antennal urinary glands in the ontogeny of osmoregulatory functions was investigated during the development of astacus leptodactylus by measurements of hemolymph and urine osmolality in juvenile and adult crayfish and by the immunodetection of the enzyme na+,k+-atpase. in stage ii juveniles, 1-year-old juveniles, and adults, all of which were maintained in freshwater, urine was significantly hypotonic to hemolymph. in adults, chloride and sodium concentrations were much lo ... | 2005 | 15517399 |
| ontogeny of the antennal glands in the crayfish astacus leptodactylus (crustacea, decapoda): anatomical and cell differentiation. | the ontogeny of the antennal glands was studied during the embryonic and post-embryonic development of astacus leptodactylus. the future glands arising from undifferentiated columnar cells were detectable at the metanauplius stage ei 150 microm (ei: eye index; approximately 440 microm at hatching). the tubule and labyrinth differentiated in embryos at ei 190 microm, and the bladder and coelomosac at ei 250 microm. at ei 350 microm, the tubule lengthened and divided into proximal and distal sub-r ... | 2005 | 15517398 |
| nitrite toxicity to crayfish, astacus leptodactylus, the effects of sublethal nitrite exposure on hemolymph nitrite, total hemocyte counts, and hemolymph glucose. | the 48-h acute toxicity range of nitrite to narrow-clawed crayfish, astacus leptodactylus was within 22 and 70 mg l(-1) (mean 29.43 mg l(-1)). environmental chloride (100 mg l(-1) chloride) increased the 48-h toxicity of nitrite to a range of 31 and 80 mg l(-1) (mean 49.20 mg l(-1)). hemolymph nitrite, total hemocyte counts (thcs), and hemolymph glucose were examined in a. leptodactylus exposed to different sublethal nitrite concentrations. the same parameters were also determined for a. leptoda ... | 2004 | 15388276 |
| occurrence of l- and d-crustacean hyperglycemic hormone isoforms in the eyestalk x-organ/sinus gland complex during the ontogeny of the crayfish astacus leptodactylus. | we studied the ontogeny of the eyestalk structure and of the l-chh and d-phe3-chh synthesis in the x-organ/sinus gland (xo/sg) complex by light microscopy and immunocytochemistry in the freshwater crustacean astacus leptodactylus. the optic ganglia start to differentiate in embryos at ei 190 microm (ei: eye index; close to 410 microm at hatching). at ei 270 microm, the three medullae (externa, interna, and terminalis) and the lamina ganglionaris are present and are organized as in the adult eyes ... | 2004 | 15314080 |
| differences in the crista dentata structure of the ischium of the third maxilliped in astacus leptodactylus (eschscholtz, 1823). | the differences in the crista dentata structure of the ischium of third maxilliped in different size astacus leptodactylus (36-80 mm carapace length) were investigated. the results showed that four different types of crista dentata structure and teeth number occur in the third maxillipeds of a. leptodactylus. these are: (1) same number of teeth in the crista dentata of right and left third maxilliped, but not in the same structure, (2) different number and structure of teeth in the crista dentat ... | 2003 | 14686655 |
| posttranslational isomerization of a neuropeptide in crustacean neurosecretory cells studied by ultrastructural immunocytochemistry. | isomerization of the third amino acid residue (a phenylalanine) of crustacean hyperglycemic hormone (chh) has been previously reported to occur as a late step of hormone precursor maturation in a few neurosecretory cells in the x-organ-sinus gland complex of the crayfish orconectes limosus. in the present report, using conformation-specific antisera combined with immunogold labeling, we have studied, at the ultrastructural level, the distribution of l- and d-chh immunoreactivity in chh-secreting ... | 2003 | 14533741 |
| putative involvement of crustacean hyperglycemic hormone isoforms in the neuroendocrine mediation of osmoregulation in the crayfish astacus leptodactylus. | this study investigates the involvement of eyestalk neuroendocrine factors on osmoregulation in the crayfish astacus leptodactylus maintained in freshwater. eyestalk removal was followed by a significant decrease in hemolymph osmolality and na(+) concentration and by a 50% increase in mass after one molting cycle. several neurohormones have been isolated from the sinus gland through high-performance liquid chromatography (hplc), and different crustacean hyperglycemic hormone (chh)-related peptid ... | 2003 | 12582140 |
| stimulation of gaba release by scorpion venom in an isolated synapse in the crayfish (astacus leptodactylus). | effects of various types of scorpion venom on gamma-aminobutyric acid (gaba) release were studied in an isolated synapse in the crayfish. post-synaptic gaba-induced currents were recorded to monitor the gaba release from the pre-synaptic site. in 20mm tetraethylammonium (tea) chloride solution the gaba-induced currents increased 71%. exposing the preparations to leiurus quinquestriatus hebraeus, leiurus quinquestriatus quinquestriatus or tityus serrulatus venom (0.1mg/ml) increased gaba-induced ... | 2003 | 12565762 |
| bioelectric field potentials of the ventilatory muscles in the crayfish. | this study investigated the pattern of the electrical field potentials recorded near the prebranchial chamber of the native crayfish astacus leptodactylus. inside the prebranchial chamber, the electrical waves had maximal amplitude and showed 2-4 peaks per cycle. potentials with the same frequency but smaller amplitude and simpler shape were also recorded outside the chamber, near the edge of the carapace, and at some distance towards the caudal direction. correlation of these electrical potenti ... | 2003 | 12547276 |
| tyrosinases from crustaceans form hexamers. | tyrosinases, which are widely distributed among animals, plants and fungi, are involved in many biologically essential functions, including pigmentation, sclerotization, primary immune response and host defence. in the present study, we present a structural and physicochemical characterization of two new tyrosinases from the crustaceans palinurus elephas (european spiny lobster) and astacus leptodactylus (freshwater crayfish). in vivo, the purified crustacean tyrosinases occur as hexamers compos ... | 2003 | 12466021 |