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1.
J Fish Biol ; 87(3): 634-45, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26242690

ABSTRACT

A comparative cytogenetic analysis, using both conventional staining techniques and fluorescence in situ hybridization, of six Indo-Pacific moray eels from three different genera (Gymnothorax fimbriatus, Gymnothorax flavimarginatus, Gymnothorax javanicus, Gymnothorax undulatus, Echidna nebulosa and Gymnomuraena zebra), was carried out to investigate the chromosomal differentiation in the family Muraenidae. Four species displayed a diploid chromosome number 2n = 42, which is common among the Muraenidae. Two other species, G. javanicus and G. flavimarginatus, were characterized by different chromosome numbers (2n = 40 and 2n = 36). For most species, a large amount of constitutive heterochromatin was detected in the chromosomes, with species-specific C-banding patterns that enabled pairing of the homologous chromosomes. In all species, the major ribosomal genes were localized in the guanine-cytosine-rich region of one chromosome pair, but in different chromosomal locations. The (TTAGGG)n telomeric sequences were mapped onto chromosomal ends in all muraenid species studied. The comparison of the results derived from this study with those available in the literature confirms a substantial conservation of the diploid chromosome number in the Muraenidae and supports the hypothesis that rearrangements have occurred that have diversified their karyotypes. Furthermore, the finding of two species with different diploid chromosome numbers suggests that additional chromosomal rearrangements, such as Robertsonian fusions, have occurred in the karyotype evolution of the Muraenidae.


Subject(s)
Chromosome Banding , Eels/genetics , In Situ Hybridization, Fluorescence , Animals , Biological Evolution , Diploidy , Eels/classification , Female , Heterochromatin , Indian Ocean , Karyotype , Male , Nucleolus Organizer Region/genetics , Telomere/genetics
2.
Genet Mol Res ; 11(3): 2745-8, 2012 Aug 17.
Article in English | MEDLINE | ID: mdl-22930408

ABSTRACT

Fourteen microsatellite markers were isolated from the giant red shrimp Aristaeomorpha foliacea (Risso, 1827) using the FIASCO protocol (fast isolation by AFLP of sequences containing repeats). Polymorphism was assessed in 30 individuals from two localities of the western Mediterranean basin (N = 20 from Sardinia and N = 10 from Sicily); nine loci showed polymorphism with 2 to 19 alleles per locus (average: 8.9). Polymorphic information content ranged from 0.36 to 0.91, and the observed and expected heterozygosities ranged from 0.50 to 0.97 and from 0.47 to 0.93, respectively. Two loci showed significant deviation from Hardy-Weinberg equilibrium, and evidence of linkage disequilibrium was found for only one locus pair. These loci are the first to be characterized in A. foliacea and could be effective tools for the investigation of genetic diversity, population structure, and demographic connectivity, useful information for the management of this important commercial resource.


Subject(s)
Crustacea/genetics , Genome/genetics , Microsatellite Repeats/genetics , Animals , Genetic Loci/genetics , Genetic Markers , Molecular Sequence Data
3.
Eur J Histochem ; 55(2): e12, 2011 May 27.
Article in English | MEDLINE | ID: mdl-22193293

ABSTRACT

Muraenidae is a species-rich family, with relationships among genera and species and taxonomy that have not been completely clarified. Few cytogenetic studies have been conducted on this family, and all of them showed the same diploid chromosome number (2n=42) but with conspicuous karyotypic variation among species. The Mediterranean moray eel Gymnothorax unicolor was previously cytogenetically studied using classical techniques that allowed the characterization of its karyotype structure and the constitutive heterochromatin and argyrophilic nucleolar organizer regions (Ag-NORs) distribution pattern. In the present study, we describe two new repetitive elements (called GuMboI and GuDdeI) obtained from restricted genomic DNA of G. unicolor that were characterized by Southern blot and physically localized by in situ hybridization on metaphase chromosomes. As they are highly repetitive DNA sequences, they map in heterochromatic regions. However, while GuDdeI was localized in the centromeric regions, the GuMboI fraction was distributed on some centromeres and was co-localized with the nucleolus organizer region (NOR). Comparative analysis with other Mediterranean species such as Muraena helena pointed out that these DNA fractions are species-specific and could potentially be used for species discrimination. As a new contribution to the karyotype of this species, we found that the major ribosomal genes are localized on acrocentric chromosome 9 and that the telomeres of each chromosome are composed of a tandem repeat derived from a poly-TTAGGG DNA sequence, as it occurs in most vertebrate species. The results obtained add new information useful in comparative genomics at the chromosomal level and contribute to the cytogenetic knowledge regarding this fish family, which has not been extensively studied.


Subject(s)
Chromosomes/genetics , Eels/genetics , Polymorphism, Genetic , Repetitive Sequences, Nucleic Acid/genetics , Animals , Chromosome Mapping/methods
4.
J Hazard Mater ; 172(1): 13-9, 2009 Dec 15.
Article in English | MEDLINE | ID: mdl-19643534

ABSTRACT

Grape stalk is an organic waste produced in great amounts in the industrialization processes of grape. This work presents the results of studies carried out to use this waste as raw material to prepare activated carbon through the physical and chemical route. The physicochemical characterization of this material suggests the presence of unusually high levels of ashes. Metal content was determined and high levels of potassium, sodium, iron, calcium and magnesium in carbonized and raw grape stalk were exhibited. This characteristic made difficult physical activation at high temperatures. A leaching step was included before the activation with steam, and adsorbents with surface areas between 700 and 900 m(2)/g were obtained. Physical activation was also performed at lower temperatures using carbonized grape stalk without leaching, leading to the development of some grade of porosity, with an area of 412 m(2)/g. These results would indicate the catalytic effect of the minerals present in this raw material. Chemical activation using phosphoric acid as activating agent seemed to be a very efficient method as final products with BET areas between 1000 and 1500 m(2)/g were obtained.


Subject(s)
Agriculture/methods , Carbon/chemistry , Charcoal/chemistry , Adsorption , Calcium/analysis , Cellulose/chemistry , Iron/analysis , Lignin/chemistry , Magnesium/analysis , Phosphoric Acids/chemistry , Potassium/analysis , Refuse Disposal/methods , Sodium/analysis , Vitis , Waste Disposal, Fluid/methods
5.
Genetica ; 135(3): 283-8, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18500652

ABSTRACT

The karyotype of the finless eel Dalophis imberbis was investigated by conventional (C and replication banding, CMA(3) fluorescence) and molecular (FISH with 45S rDNA probe) techniques. The diploid chromosome number was 2n = 46 and the karyotype consisted of four pairs of meta-submetacentric and 18 pairs of subtelo-acrocentric autosomes and a pair of sex chromosomes heteromorphic in females, composed by a large subtelocentric Z, and a medium sized acrocentric W chromosome; in males this pair was composed by two large subtelocentric ZZ chromosomes. Multiple NORs have been localized by FISH and have been found to be CMA(3) positive; one of the NORs was located on the W chromosome and it was found transcriptionally active by silver staining. The Z chromosome contained distinct intercalar C-positive heterochromatin and W was almost completely heterochromatic. Our report contributes to the knowledge to the cytotaxonomy of Anguilliformes where differentiated sex chromosomes are reported in about a quarter of the species: both male and female heterogamety as well as a multiple chromosome system have been reported. Moreover, this is the first anguilliform species in which multiple NORs have been reported.


Subject(s)
Eels/genetics , Sex Chromosomes/genetics , Animals , Chromosome Mapping , Female , In Situ Hybridization, Fluorescence , Karyotyping , Male
6.
Cytogenet Genome Res ; 106(2-4): 215-21, 2004.
Article in English | MEDLINE | ID: mdl-15292594

ABSTRACT

Among crustacean Decapoda numerical chromosome variability is frequent, and it has been hypothesized that the presence of supernumerary chromosomes accounts for this variability. Thanks to the improvement of cytogenetic analysis by chromosomal banding techniques, supernumerary B chromosomes (Bs) have been demonstrated in Nephrops norvegicus, Homarus americanus,Palinurus elephas and P. mauritanicus, belonging to different crustacean families. In all four species Bs were variable in number, mainly heterochromatic and undigested by various endonucleases, and in meiosis they showed non-Mendelian segregation. Compared to the other chromosomes of the complement, the Bs are very small in almost all species, but some of them were very large in N. norvegicus.


Subject(s)
Chromosomes/genetics , Decapoda/genetics , Humans
7.
Genetica ; 119(3): 253-8, 2003 Nov.
Article in English | MEDLINE | ID: mdl-14686604

ABSTRACT

Early and late replication bandings have been obtained by in vitro BrdU incorporation in the Mediterranean Muraenidae species Muraena helena and Gymnothorax unicolor, and used to characterize their karyotypes. A comparative analysis of the banding patterns allowed to point out high karyotype similarity as well as chromosome rearrangements that occurred in karyotype evolution between these species.


Subject(s)
Chromosome Banding , Chromosomes/genetics , Eels/genetics , Evolution, Molecular , Animals , Bromodeoxyuridine , Female , Karyotyping , Male , Mediterranean Sea
8.
Eur J Biochem ; 268(14): 4104-11, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11454005

ABSTRACT

The Gymnothorax unicolor hemoglobin system is characterized by two components, called cathodic and anodic on the basis of their isoelectric point, which were separated by ion-exchange chromatography. The oxygen-binding properties of the purified components were studied in the absence and presence of chloride and/or GTP or ATP in the pH range 6.5-8.0. Stripped cathodic hemoglobin showed a small reverse Bohr effect, high oxygen affinity, and low co-operativity; the addition of chloride only caused a small decrease in oxygen affinity. In the presence of GTP or ATP, the oxygen affinity was dramatically reduced, the co-operativity increased, and the reverse Bohr effect abolished. Stripped anodic hemoglobin is characterized by both low oxygen affinity and co-operativity, and displayed a normal Bohr effect; the addition of chloride increased co-operativity, whereas ATP and GTP significantly modulated oxygen affinity at acidic pH values, enhancing the Bohr effect and giving rise to the Root effect. The complete amino-acid sequences of the alpha and beta chains of both hemoglobins were established; the molecular basis of the functional properties of the hemoglobins is discussed in the light of the primary structure and compared with those of other fish hemoglobins.


Subject(s)
Fishes , Hemoglobins/physiology , Allosteric Regulation , Amino Acid Sequence , Animals , Hemoglobins/chemistry , Molecular Sequence Data , Oxygen/metabolism , Phosphates/metabolism , Sequence Homology, Amino Acid , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
10.
Chromosome Res ; 8(3): 213-8, 2000.
Article in English | MEDLINE | ID: mdl-10841048

ABSTRACT

Major and 5S ribosomal genes have been localized in the chromosomes of Micropterus salmoides. By C-banding, Ag-staining, CMA3-staining and 45S and 5S fluorescence in-situ hybridization (FISH), we demonstrate that the 45S and 5S ribosomal genes are clustered in two different chromosome pairs and both are located in heterochromatic GC-rich regions. PCR amplification and sequencing of the 5S intergenic non-transcribed sequences have allowed us to identify variability essentially due to a trinucleotide tandem repeat (GCT).


Subject(s)
Bass/genetics , DNA, Ribosomal/genetics , Genome , RNA, Ribosomal, 5S/genetics , Animals , Base Sequence , Chromosome Banding , Female , Fluorescent Dyes , GC Rich Sequence , In Situ Hybridization, Fluorescence , Karyotyping , Male , Molecular Sequence Data , Physical Chromosome Mapping , Sequence Alignment
11.
Eur J Biochem ; 234(2): 431-6, 1995 Dec 01.
Article in English | MEDLINE | ID: mdl-8536685

ABSTRACT

Concerning the number and type of the hemoglobin components, the moray Muraena helena is characterized by three different phenotypes whose frequencies are nearly identical. Thus, the cathodal component is present in all individuals, whereas one or both of two anodal components may be present in the same phenotype. These components have been separated by chromatography. The oxygen binding properties of the purified hemoglobin components have been studied in the absence and presence of saturating concentrations of ATP or GTP and as a function of pH. The cathodal component shows an intrinsic O2 affinity four times higher than that of both anodal components, a very small Bohr effect and a significant decrease in O2 affinity upon addition of ATP and GTP (three and four times respectively with respect to stripped conditions), the latter being more effective than the former over the entire pH range examined. The anodal components do not appear functionally distinguishable and show the presence of an enhanced Bohr effect (Root effect) that is under the strict control of nucleotide triphosphates ATP, GTP, which, unlike in the cathodic component, exert the same effect on oxygen affinity. The complete sequence of the beta chains of the cathodal and of one of the anodal components have been determined. The possible molecular basis of these different functional characteristics are discussed in the light of the globin sequence and of those amino acid residues which are known to be responsible of hemoglobin functional behaviour.


Subject(s)
Eels/blood , Hemoglobins/chemistry , Amino Acid Sequence , Animals , Hemoglobins/physiology , Hydrogen-Ion Concentration , Molecular Sequence Data , Oxygen/metabolism , Structure-Activity Relationship
12.
Genome ; 38(4): 809-13, 1995 Aug.
Article in English | MEDLINE | ID: mdl-18470206

ABSTRACT

To investigate the genome of the anguilliform fish Muraena helena at the molecular level we characterized total DNA by agarose gel electrophoresis after cleavage with AluI, HaeIII, MboI, and DdeI restriction endonucleases. Subsequently, we isolated the DNA from two specific electrophoretic fractions to be used as probes for Southern and in situ hybridization experiments. One such fraction showed an electrophoretic pattern typical of highly repetitive DNA localized in the centromeres of many chromosomes. The other fraction was shown to be located in the nucleolar organizer region, partially coincident with 45S rDNA, and to be composed of highly repetitive sequences.

13.
Eur J Histochem ; 39(4): 259-64, 1995.
Article in English | MEDLINE | ID: mdl-8835179

ABSTRACT

The genome sizes (GS) and AT contents of five species of Anguilliformes (Anguilla anguilla, Anguilla rostrata, Conger conger, Gymnothorax unicolor and Muraena helena) belonging to three families (Anguillidae, Congridae and Muraenidae) were determined by flow cytometry and densitometry. Differences in Gs between Anguillidae-Congridae (about 3 pg) and Muraenidae (about 5 pg) were found, which correlate with the relative amounts of AT base pairs (around 42-43% for Anguillidae-Congridae and 51-52% for Muraenidae). Correlation of these results to karyotype parameters testified to a close phylogenetic relationship between Anguillidae and Congridae.


Subject(s)
Adenine/analysis , Anguilla/genetics , DNA/genetics , Genome , Thymidine/analysis , Animals , DNA/analysis , Densitometry , Flow Cytometry , Karyotyping , Ploidies
14.
Chromosome Res ; 3(1): 54-8, 1995 Jan.
Article in English | MEDLINE | ID: mdl-7704417

ABSTRACT

The distribution of (TTAGGG)n telomeric repeats was studied in chromosomes of two Atlantic eels, Anguilla anguilla and A. rostrata. We found that these sequences hybridize to all the telomeres but also to the entire nucleolar organizer region (NOR) localized in both species at the short arm of chromosome 8. This was considered to be due to the interspersion of telomeric sequences within the NOR ones. Whatever the significance of this interspersion may be, it seems to be limited to A. anguilla and A. rostrata since in Muraena helena (family muraenidae), which also belongs to the Anguilliformes, no telomeric hybridization signals were found along the NOR regions.


Subject(s)
Eels/genetics , Telomere , Animals , Chromosome Mapping , In Situ Hybridization, Fluorescence , Nucleolus Organizer Region , Ribosomes , Species Specificity
15.
Neurosci Lett ; 172(1-2): 35-8, 1994 May 19.
Article in English | MEDLINE | ID: mdl-8084534

ABSTRACT

The concentrations of dopamine (DA) and of its major metabolite, dihydroxyphenylacetic acid (DOPAC), were measured in discrete areas of the eel brain. To investigate the developmental changes in the content of DA and DOPAC, the assays were performed in yellow eels (i.e. at the feeding stage) and silver eels (i.e. at the migratory stage). DA and DOPAC were unevenly distributed in the eel brain. In yellow eels, the concentration of DA was highest (16-19 pmol/mg protein) in the olfactory bulb (OB), mesencephalic tectum-diencephalon (MT-D) and medulla oblongata (MO) and lowest in the cerebellum (CB, 1 pmol/mg protein), whereas intermediate values were measured in the telencephalon (TE; 10 pmol/mg protein). The metabolic rate of DA, as reflected by the DOPAC/DA ratio, was highest in the OB and CB, with progressively smaller values being observed in the TE, MT-D, and MO. A significant increase in the concentrations of DA (+80%) and DOPAC (+122%) was observed in the OB of silver eels compared with yellow eels, whereas no significant differences were detected in the concentrations of DA and DOPAC in the other brain areas as a function of the developmental stage. The results are discussed in terms of the possible involvement of environmental, behavioral and developmental factors.


Subject(s)
Anguilla/metabolism , Dopamine/metabolism , Olfactory Bulb/growth & development , Olfactory Bulb/metabolism , 3,4-Dihydroxyphenylacetic Acid/metabolism , Animals , Brain Chemistry/physiology
16.
Minerva Chir ; 48(17): 881-5, 1993 Sep 15.
Article in Italian | MEDLINE | ID: mdl-8290123

ABSTRACT

Of the alternative methods of treatment to surgery in the treatment of liver cancer, chemoembolization with Lipiodol appears to have obtained encouraging results. After a preoperative study to confirm the diagnosis and staging of the tumour, lipiodolisation is performed: a mix of Adriamycin, Iopamidol and Lipiodol is injected using selective catheterism of the hepatic artery; gelfoam is then added. Lipiodol selectively localises in the hepatocarcinoma and has a distal embolising effect on the vessels of the tumour, thus necrotising it, acting as a carrier for chemotherapy. Since july 1990 a total of 15 hepatocarcinoma have been observed: 6 in healthy livers and 9 in cirrhotic livers; 3 patients recovered after radical surgery, 1 patient underwent associated surgery and chemoembolization, whereas in 11 the only therapy was chemoembolization, at six monthly intervals. Lipiodolisation enabled a better diagnosis to be made and was found to be a valuable therapeutic aid both when used alone in Inoperable patients and in association with non-radical surgery.


Subject(s)
Carcinoma, Hepatocellular/therapy , Embolization, Therapeutic/methods , Iodized Oil/administration & dosage , Liver Neoplasms/therapy , Carcinoma, Hepatocellular/diagnostic imaging , Combined Modality Therapy , Doxorubicin/administration & dosage , Hepatic Artery/diagnostic imaging , Humans , Iopamidol/administration & dosage , Liver Cirrhosis/diagnostic imaging , Liver Cirrhosis/therapy , Liver Neoplasms/diagnostic imaging , Tomography, X-Ray Computed
17.
Neurosci Lett ; 133(2): 168-70, 1991 Dec 09.
Article in English | MEDLINE | ID: mdl-1667812

ABSTRACT

The binding parameters of benzodiazepine receptors labeled with [3H]flunitrazepam were investigated in the brain of male adult eels at the trophic phase (4 years old) and of male silver eels (6 year old ocean migrants). The density of [3H]flunitrazepam binding sites was significantly decreased (-26%) in the brain of silver eels compared with younger counterparts. In contrast, the apparent dissociation constant (Kd) was not significantly different in the two experimental groups. These results are discussed in terms of the possible involvement of stress, behavioral and environmental factors and age-related degenerative processes.


Subject(s)
Anguilla/growth & development , Brain/growth & development , Receptors, GABA-A/metabolism , Aging , Animals , Brain/metabolism , Cell Membrane/metabolism , Flunitrazepam/metabolism , Kinetics
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