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EN
The pattern of nucleolus attachment and C-heterochromatin distribution and molecular composition in the karyotypes of psocid species Psococerastis gibbosa (2n = 16+X), Blaste conspurcata (2n = 16+X) and Amphipsocus japonicus (2n = 14+neo-XY) were studied by C-banding, silver impregnation and sequence specific fluorochromes CMA3 and DAPI. Every species was found to have a single nucleolus in male meiosis. In P. gibbosa the nucleolus is attached to an autosomal bivalent; in B. conspurcata to the X-chromosome; in A. japonicus to the neo-XY bivalent. The species show a rather small amount of constitutive heterochromatin, C-blocks demonstrating telomeric localization with rare exceptions. P. gibbosa is characterized by a polymorphism for C-blocks occurrence and distribution. In the autosomes of this species, C-heterochromatin consists of AT-rich DNA except for the nucleolus organizing region, which is also GC-rich; the X-chromosome shows both AT- and GC-rich clusters. In A. japonicus and B. conspurcata, C-heterochromatin of the autosomes and sex chromosomes consists of both GC-rich and AT-rich DNA clusters, which are largely co-localized.
EN
Karyotypes of males of cicadas Tibicen bihamatus (Motschulski) and Platypleura kuroiwae Matsumura were studied using C-banding technique. In Tibicen bihamatus two types of C-band distribution were observed. Two chromosome pairs have C-bands at one of the chromosome ends, while in the other, including the sex chromosome, C-heterochromatin blocks occurred at both ends. Platypleura kuroiwae has a smaller amount of C-heterochromatin located as small subterminal blocks. The intercalar C-bands were seen in the early spermatogonial metaphase chromosomes.
Folia Biologica
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2007
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vol. 55
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issue 3-4
115-120
EN
The karyotype of the mallard duck, Anas platyrhynchos, was characterised on the basis of R and C bands. Chromosomal preparations obtained from in vitro blood lymphocyte cultures were RBG- and CBG-stained. The structures of nine and 14 pairs of chromosomes were analysed by the RBG and CBG chromosome banding techniques, respectively. The location of R bands, as well as the size and arrangement of constitutive heterochromatin blocks were determined. Ideograms of R and C banded patterns of the analysed chromosomes were drawn. The morphological makeup of the analysed chromosomes was assessed.
EN
Karyotypes and C-heterochromatin distribution of Deracanthina deracanthoides, Deracanthella verrucosa and Zichya baranovi were studied. Differences in the chromosome numbers, their morphology, and the position of C-bands between species of Bradyporinae are discussed.
EN
Karyotypes, C-bands distribution of nine species belonging to 6 genera, and chromosomal location of NORs in some species were studied. Differences in the chromosome numbers, their morphology, and the position of C-bands between species of Poecilimon and IIsophya are discussed.
EN
Karyotypes and morphology of the male reproductive system of seven species of Psylloidea (Trioza abdominalis, T. cirsii, T. dispar, T. flavipennis, T. munda, T. senecionis, and Bactericera femoralis) were described for the first time.
EN
The karyotype of the domestic goose A. cygnoides was characterised on the basis of R and C bands. Chromosomal preparations obtained from an in vitro culture of blood lymphocytes were stained by means of the RBG and CBG banding techniques. The first nine pairs of chromosomes were analysed by the R banding technique, while fourteen pairs of chromosomes were analysed by the C banding technique. The localisation of R bands as well as the sizes and positions of constitutive heterochromatin blocks were determined. Ideograms of R and C banded patterns for the analysed chromosomes were drawn. The morphological make-up of the analysed chromosomes was assessed.
EN
The karyotypes of three species of fish of the Cichlidae family from the Forqueta river and several locations in Gua?ba lake/RS (Brazil) were analyzed. All species presented 2n=48, while Gymnogeophagus gymnogenys showed two karyotypic formulae: 4m+44st-a with FN=52 and 6m+42st-a with FN=54. Gymnogeophagus labiatus presented 4m+4sm+40st-a and FN=56 and Geophagus brasiliensis 4sm+44st-a and FN=52. Simple NORs were found in all species with the exception of a population of G. gymnogenys from Saco da Alemoa/Barra do Ribeiro. CMA3 staining revealed NOR sites, while DAPI staining was negative and heterochromatin was limited to pericentromeric regions and associated to NORs, except in G. labiatus. The data show a conserved pattern in Geophagus brasiliensis and karyotype variation in the species of Gymnogeophagus.
EN
A cytogenetic study was conducted on two species of the genus Pimelodus that were collected from the Piquiri river, Paran?, Brazil: Pimelodus paranaensis and Pimelodus heraldoi. Both had a diploid number of 2n=56 chromosomes and a fundamental number (FN) of 104. In P. paranaensis, the karyotype consisted of 22m+22sm+4st+8a chromosomes, whereas the karyotype of P. heraldoi consisted of 18m+24sm+6st+8a. The AgNORs were localized in the terminal region of the long arm in one pair of subtelocentric chromosomes, pair 24 in P. paranaensis and pair 23 in P. heraldoi. The latter species showed size heteromorphism of these regions between the chromosome homologues. Heterochromatin was distributed mainly in the terminal regions in the two species. CMA3-positive staining was observed in some chromosomes, besides being associated with NORs, which were all DAPI-negative, in both species of Pimelodus. C-banding plus CMA3 and DAPI showed that most of the heterochromatic regions were rich in AT bases in P. paranaensis and P. heraldoi.
EN
The karyotype in two species of Cacopsylla (Homoptera, Psyllidae) from populations was investigated.The males were found to be dimorphic with respect to their sex chromosome constitution and the automosome number.Type A (XO) was described for C sorbi.Type B (XY) was described for C mali and Type C (X1X2Y)for two species in the present work.In Type B and Type C reduction of the autosome number was found.The bahaviour of sex chromosome during meiosis was studied.The scheme was proposed indicationg how the XO type, through X-autosome fusion, gave rise to the neo X1X2Y type.
EN
In this case report we present a child with an additional chromosome in the karyotype. The karyotypes of the boy and his parents were analyzed by use of a conventional banding technique (GTG) and fluorescence in situ hybridization (FISH). Probes painting whole chromosomes 12 and 18 were used in FISH. Cytogenetic examination of the parents revealed that his mother was carrying balanced reciprocal translocation between chromosomes 12 and 18. Her karyotype was described as 46,XX,t(12;18)(p13;q12). Father's karyotype was normal, described as 46,XY. The boy's karyotype was defined as 47,XY,+der(18)t(12;18)(p13;q12). The additional chromosome appeared probably due to 3:1 meiotic disjunction of the maternal balanced translocation, known as tertiary trisomy. The mother displayed a normal phenotype and delivered earlier a healthy child. However, the boy with the unbalanced karyotype shows multiple congenital abnormalities.
EN
Karyotypes and meiosis patterns in three obligatory thelytokous Psocoptera species have been studied for the first time. Females of Aaroniella badonneli (Danks) display 9 chiasmatic bivalents in oocyte metaphase I (2n = 18), hence meiosis is of the automictic type. Females of Ectopsocus meridionalis Ribaga and Valenzuela sp. display 3n = 27, and 27 univalent chromosomes are present in oocyte metaphase I. Thus, meiosis in these species is of the apomictic type.
EN
Karyotypes and C-banding patterns of grasshoppers, members of the subfamily Eypre- pocnemidinae Thisoicetrinus pterostichus (F.-W.), Heteracris adspersa (Redt.), Eypre- pocnemis unicolor Tarb., Eyprepocnemis plorans (Charp.), and Shirakiacris shirakii (I. Bol.) are described. Chromosome complements of these species are composed of 23 acro- centric chromosomes in the male. The sex-determining mechanism is X0_/XX_. The B chromosomes were observed in the Northern Caucasus population of E. plorans. There was no evidence for any significant effect of 2Bs on either mean chiasma frequency or between cell-variance. There was a significant increase in the mean chiasma frequency for specimens with 1B.
EN
As a part of ongoing cytogenetic studies on the jewel-beetles (Buprestidae, Coleoptera) of Armenia, the male karyotypes and meiosis of nine species (5 genera, 4 tribes, 2 subfamilies) are described, figured and discussed. In Ovalisia nadezhdae Sem., Sphenoptera artemisiae Reitt., Coraebus rubi L., C. sinuatus Creutz., Meliboeus caucasicus Reitt., Agrilus angustulus Ill. Men., A. obscuricollis Kiesw., and A. araxenus Khnz. diploid chromosome numbers vary in a narrow range from 20 to 24. In Sph. glabrata Men. a high chromosome number of 2n=40 was discovered. All the species have a XY sex chromosome system, which is however of different types. The data available on the buprestid karyotypes and karyotype variation at different taxonomic levels within the family are discussed.
EN
Karyotypes (the number, shape, C-bands, NORs, chiasma frequency) of four species of Landrevinae were studied. Three species are characterized by a karyotype of 2n male=19 - Duolandrevus (Eulandrevus) sonorus, D. (E.) dendrophilus and D. (E.) enatus while Vasilia vietnamensis showed 2n=17. Differences of karyotypes are connected with simple Robertsonian translocation in autosomes. Successive stages of spermatogenesis were analysed.
EN
first time. The diploid chromosome numbers of males were found to be 2n=61 in L. pilosus, 2n=69 in L. siculus and 2n=73 in L. cretonatus. Karyotypes of all species mainly consist of biarmed chromosomes; the sex chromosome system is X0. Remarkably, the X chromosome displays partial (L. cretonatus), or even total (L. pilosus), negative heteropycnosis during the spermatogonial metaphase.
EN
Cytogenetic studies, carried out between 1978 - 1998 at the National Research Institute of Animal Production resulted in identification of several chromosomal aberrations as follows: chromosomal chimerism XX/XY in cattle, sheep and horses, Robertsonian translocations and sex chromosome trisomy in cattle, reciprocal translocations in pigs and sheep, pericentric inversion in pigs. The influence of Robertsonian and reciprocal translocations on fertility of aberration carriers was evaluated and economic losses in pigs due to decreased fertility were calculated. In the light of these results it is advisable to continue cytogenetic control of farm animals in Poland, mainly males being used in reproduction.
EN
Cytogenetic studies were carried out on seven specimens of Pimelodus heraldoi and sixteen specimens of Pimelodus sp., both from the Parana River basin. The two species had the same diploid number of 56 chromosomes: P. heraldoi with 22M+22SM+6ST+6A and FN of 106 and Pimelodus sp. with 24M+26SM+4ST+2A and FN of 110. NORs were found at the terminal position of the long arm of one pair of ST chromosomes. C-banding (CB) showed in the two species heterochromatin distributed in various chromosomes of the complement, mainly in telomeric regions and in a pair of metacentric chromosomes with strong heterochromatic staining in both telomeres. Treatment only with the fluorochrome CMA3 confirmed in Pimelodus heraldoi and Pimelodus sp. the nucleolar chromosome pair and showed other fluorescent bands. Combined treatment with CB+CMA3 enhanced fluorescent staining of chromosomes in the two fish species evidencing several bands, including in P. heraldoi a chromosome pair showing fluorescent staining in both telomeres.
EN
The C-stained karyotypes of five species of three dragonfly families from Western Siberia and Kunashir Island have been analysed. Gomphus epophtalmus Sel., G. vulgatissimus (L.), Nihonogomphus ruptus (Sel. et Hag.) (Gomphidae), and Anotogaster sieboldii (Sel.) (Cordulegasteridae) showed usual character of C-heterochromatin distribution, all chromosomes have terminal C-bands. Somatochlora graeseri Sel. (Corduliidae) has unique for dragonflies type of terminal C-blocks on autosomes. Three pairs of autosomes have the very large heterochromatic blocks, other chromosomes, including the X, have no C-band.
EN
The karyotype of Poecilimon brunneri and P.zwicki is described. In both species it possesses the primitive character. The relative length of chromosome in P. brunneri and P. zwicki are compared. Both species have an unstable B chromosome and aberrations in autosomes. In P. zwicki the X chromosome shows euchromatic segments of different size and place.
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