Navegando por Orientadores "PIECZARKA, Julio Cesar"

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Análise citogenética comparativa em espécies de morcegos da subfamília phyllostominae (chiroptera-phyllostomidae) por citogenética clássica e hibridização in situ Flourescente (fish)
(Universidade Federal do Pará, 2011-03-29) SILVA, Natalia Karina Nascimento da; PIECZARKA, Julio Cesar; http://lattes.cnpq.br/6644368250823351
Bats are a highly distributed and diversified group.The diversity of feeding habits makes the Order Chiroptera one of the highest successes among mammals, being very important, because of these habits, on the control of insects, on pollination, and on dispersion of seeds of many vegetables. The family Phyllostomidae is the third bigger family on number of species into the Order Chiroptera. Among the neotropical ones, this family is the most numerous, being found in the rainforests of South America, especially in the Amazon region, where there is the highest diversity of bats in the World. In the present work it was analyzed cytogenetically a sample of three species of the subfamily Phyllostominae: Chrotopterus auritus, Trachops cirrhosus and Vampyrum spectrum collected in the Pará and Amazon states. The chromosomal data obtained for Chrotopterus auritus (2n = 28 e NF = 52) and Trachops cirrhosus (2n = 30, FN = 56) are in agreement with the ones described in the literature. For Vampyrum spectrum (2n=30 NF=56) we described for the fist time the banding patterns and FISH (Fluorescent in situ Hybridization). The C-banding technique demonstrated a pericentric pattern of distribution of the centromeric heterochromatin in the three species here studied. The FISH with telomeric DNA probes shown only distal hybridizations in all chromosomes of the three species, while the 18S rDNA proble confirmed the location of the NOR observed by Ag-NOR staining, in the long arm of pair 2 Chrotopterus auritus, in the pair 11 of Trachops cirrhosus and in the long arm of the pair 1 of Vampyrum spectrum. The comparative analysis among the species suggests an extensive chromosomal differentiation, with few chromosome pairs being shared among the three genera. Five whole chromosome pairs were conserved without any rearrangement after the divergence of the three lineages. The comparison among the species shows that C. auritus and V. spectrum have more shared pairs between them than with T. cirrhosus. Our results support the phylogenetic association between C. auritus and V. spectrum and suggest the association of T. cirrhosus with the genus Phyllostomus.
Acesso aberto (Open Access)
Análise citogenética em morcegos da família Emballonuridae (Chiroptera) da Amazônia Brasileira através de citogenética clássica e molecular
(Universidade Federal do Pará, 2011-04-29) ARAÚJO, Ramon Everton Ferreira de; PIECZARKA, Julio Cesar; http://lattes.cnpq.br/6644368250823351
This is the first description of the karyotypes of bats of the family Emballonuridae from the Brazilian Amazon region. The species studied were Cormura brevirostris-CBR (2n=22; NF=40), Rhynchonycteris naso-RNA (2n=22 and NF=36), Saccopteryx canescens-SCA (2n=24 and FN=38) and Saccopteryx leptura-SLE (2n=28 and NF=38), characterized by G-, C-banding, NOR-staining and Fluorescent In Situ Hybridization (FISH). In CBR the karyotypes found had the same diploid number and fundamental number than in literature. FISH with ribosomal DNA probes and Ag-NOR staining showed two NOR places. Hybridization with telomeric probes showed that the sequences were found in the centromeres of all chromosomes but the Y. Using meiotic studies, chromosome banding and FISH with a whole X chromosome probe from Phyllostomus hastatus (Chiroptera, Phyllostomidae) we suggest that the sex chromosome pair of this species is not the one described in the literature. Cells in diploid and diakinesis had a ring conformation with four chromosome pairs, what suggests multiple reciprocal translocations among these chromosomes, a very rare situation in vertebrates and never found in eutherian mammals. The analyses of RNA, SCA and SLE shows that the karyotypes of Emballonuridae are very conservative even when compared with samples collected geographically very far, but the C-banding analyses shows that it can happen intraspecific variations in the constitutive heterochromatin. For the first time the Nucleolar Organizer Regions were described, showing a stained pair of chromosomes on each analyzed species. The FISH with 18S rDNA probes agrees with the Ag-NOR staining. FISH with human telomeric probes showed hybridizations in the distal portion of all chromosomes. These works are Important to understand the biodiversity of bats from the Amazon region, as well as the comprehension of the chromosomal evolution of Chiroptera.
Acesso aberto (Open Access)
Análise de células-tronco adultas (CTA) em cultura de células de tecido epitelial de pequenos roedores (rodentia-stricognathi- sciurognathi)
(Universidade Federal do Pará, 2012-11-13) RISSINO, Jorge Dores; PIECZARKA, Julio Cesar; http://lattes.cnpq.br/6644368250823351
The Adult Stem Cells (ASC) are non-specialized multipotent cells found in the bone marrow, peripheral blood, cornea, retina, brain, muscles, dental pulp, liver, pancreas, skin epithelium, digestive system, umbilical cord and placenta. These cells can indefinably reproduce and renew themselves and, under some stimulation, to change into specialized cells of different tissues or organs. The present work had the aim of obtaining ASC from epithelial tissues from wild rodents of different species (Oecomys concolor – one female, Proechimys roberti – two males, Hylaeamys megacephalus – two males). The methodology for isolation and in vitro culture of epithelial tissue following the previously described protocols, as well as the analysis after cryopreservation of morphology, genome stability, counting and cells viability, clonogenic potential and differentiation on osteocytes, chondrocytes and adipocytes. The ADC were characterized as a homogeneous population of in vitro growing cells adherent to plastic surfaces, which has a morphology similar to fibroblasts and with fusiform shape, with high growing rate and cell proliferation form many successive passages, where the clonogenic assays evaluated the cell renewing. On checking the genome stability on P3, the entire sample had stable karyotypes with the correct diploid number. The methodology for ASC differentiation into osteocytes, chondrocytes and adipocytes cell lines was satisfactory and the cells demonstrated the staining with Alizarin Red S, Alcian Blue and Oil Red O, respectively. The entire sample had capacity of proliferation and differentiation, being a potential source of skin ASC. These species can be used as models for ASC studies.
Acesso aberto (Open Access)
Descrição cariotípica de peixes dos gêneros Baryancistrus, Parancistrus, Peckoltia e Ancistrus (Ancistrinae, Loricariidae) da Bacia Amazônica
(Universidade Federal do Pará, 2003-06-13) SOUZA, Augusto Cesar Paes de; PIECZARKA, Julio Cesar; http://lattes.cnpq.br/6644368250823351
The subfamily Ancistrinae is one of the most diversified among Loricariidae fish, including approximately 200 species, distributed in 26 genera. These fish are easily recognized by the presence of bony plates arranged in series along the body, and by the antero-ventral position of the mouth. Their common names are acaris, bodós, cascudos and sucker-mouth. Species of the subfamily Ancistrinae comprise an important social-economic resource, constituting one of the most important commercial activities in Altamira-PA. In this study, the karyotype of nine species of fish belonging to four different genera (Baryancystrus, Parancistrus, Peckoltia and Ancistru,$) of the subfamily Ancistrinae were analyzed through conventional (Giemsa, C-band and Ag-NORs) and fluorochrome (Chromomycin A3) techniques. The species of the genus Baryancistrus showed a diploid number 2n= 52, and FN=104. NORs were found in an interstitial position of the short arm of a biarmed chromosome. The species B. aff niveatus had large blocks of constitutive heterochromatin, rich in G-C. This character was considered apomorphic. Hence, the karyotype of this species was considered the most derived among the species of this genus. Genus Parancistrus includes species with a karyotypic structure very similar to the one found in Baryancistrus, and the position of NORs could be considered as a possible apomorphy shared by these two genera. The species of the genus Peckoltia showed a diploid number with 52 chromosomes, and FN=102, with large heterochromatic blocks in ali the species. These blocks comprised almost ali the long arras of some submetacentric and subtelocentric chromosome pairs, which could be considered as a possible apomorphy shared by the species of this group. NORs were found in the long arm of a submetacentric pair in P. vittata, and in the maximum of three chromosomes in Peckoltia spl and Peckoltia sp2. Ancistrus ranunculus showed the most derived karyotype among all the species analyzed in this study. This karyotype had 48 chromosomes and FN=80. Cytogenetic analyses so far suggest that inversions were the most important rearrangement that occurred during the chromosomal diversification of Ancistrinae, except in Ancistrus ranunculus, in which Robertsonian rearrangements were also observed.
Acesso aberto (Open Access)
Estudos cromossômicos em anuros das famílias Hylidae rafinesque, 1815 e Leptodactylidae werner, 1896 (Amphibia: Anura)
(Universidade Federal do Pará, 2010) SUAREZ, Pablo; PIECZARKA, Julio Cesar; http://lattes.cnpq.br/6644368250823351
Although there exists a large variety of chromosomal complements in Leptodactylidae (2n = 18 to 2n = 26) and Hylidae (2n = 20 to 2n = 32), the high fragmentation of data limits the access to the information about the origins and underlying mechanisms of its diversity. This, probably, had influence on the use of cytogenetic data on the characterization of species status more than been widely included in phylogenetic analyses. This work approaches, through cytogenetic data, some evolutionary aspects of three maior groups of anurans widely distributed in the Neotropical region. The genus Leptodactylus is clustered with Hydrolaetare, Paratelmatobius and Scythrophrys in the family Leptodactylidae. The chromosomal background in the genus indicates variation of the diploid numbers from 2n = 18 to 2n = 26, as well as, variation on the fundamental numbers (number of autosomic arms, FN) and on the position of Nucleolus Organizer Regions (NOR). Results of the analysis of 26 species of Leptodactylus, using several techniques, probably represents the most inclusive cytogenetic analyses on the genus Leptodactylus until now and its results provides appropriate bases to establish consistent relationships of chromosomal evolution on the genus Leptodactylus. Actually the Lophyiohylini tribe cluster 81 species distributed in 10 genera. The cytogenetic information is scarce and restrict to only 12 species. In the present study, are presented, comparatively, cytogenetic data of species from Argenteohyla, Itapotihyla, Phyllodytes, Trachycephalus and Osteocephalus genera. With exception of O. buckleyi (2n = 26; NF = 50) and P. edelmoi (2n = 22; NF = 44), the results indicate that all the others analyzed species coincide with cytogenetic data available, that indicates 2n = 24 (NF = 48) on the majority of karyotyped species, with NOR and secondary constrictions (SC) located on the 11 pair. However, in Phyllodytes edelmoi and Argentohyla siemersi pederseni, these regions are located on pairs 2 and 5, respectively. Heterochromatic blocks were associated to additional SC (fragile sites) in Osteocephalus, but not in Trachycephalus. Cytogenetic data on the Nyctimantis and Tepuihyla genera, techniques with techniques with higher resolution and more inclusive studies are necessary to better comprehend the chromosomal evolution of the tribe. The Dendropsophini tribe actually clusters the Scinax, Pseudis, Scarthyla, Sphaenorhynchus, Xenohyla and Dendropsophus genera. The registered cytogenetic data of all the genera revealed high karyotype diversity with great variation on the diploid numbers (2n = 22 in Scarthyla; 2n = 24 in Scinax and Xenohyla; 2n = 24, 24 +1- 2B e 26 in Sphaenorhynchus; 2n = 24 and 28 in Pseudis; and, 2n = 30 in Dendropsophus). The 2n=24 observed in X. truncata indicates that 2n=30 constitute a synapomorphy of the Dendropsophus genus. The NOR localization on the pair 7 is a characteristic shared by species of Scarthyla, Xenohyla, Pseudis and Sphenorhynchus, with some exceptions in the last two genera (P. caraya and S. carneus). However, the Dendropsophus genus displays an interesting diversity related to the number and its localization. On the other hand, the heterochromatin distribution presented standard variables, particularly on genus Pseudis. Although there is an exceptional chromosome variation in this group, fragmentary information in some genera made difficult to formulate consistent hypotheses about the role of chromosomes in the evolution of the group.
Acesso aberto (Open Access)
Evolução cromossômica e mapeamento genômico comparativo em morcegos da subfamília Phyllostominae (Mammalia, Chiroptera)
(Universidade Federal do Pará, 2016-07-11) SILVA, Natalia Karina Nascimento da; PIECZARKA, Julio Cesar; http://lattes.cnpq.br/6644368250823351
Acesso aberto (Open Access)
Integração dos estudos cromossômicos e DNA barcoding em Rhamphichthys (Pisces: Gymnotiformes)
(Universidade Federal do Pará, 2016-05-16) SILVA, Patrícia Corrêa da; PIECZARKA, Julio Cesar; http://lattes.cnpq.br/6644368250823351
The Order Gymnotiformes is composed by 219 valid species, which are distributed in five families. The most investigated genera are Eigenmannia and Gymnotus. Our work focused on family Rhamphichthyidae, genus Rhamphichthys that, like other Gymnotiformes, present greater abundance and diversity in the Amazon region. Sampling was carried out in the municipalities of Abaetetuba, Barcarena and Belém (Pará) and Tefé, Ecological Reserve Mamirauá (Amazonas), in order to better define the species, through the integration of classical cytogenetic data, cytogenomic analysis (probes for repetitive DNA sequences) and DNA Barcoding and thus understand the evolution of this fish in the Amazon. A new karyotype was identified for R. rostratus with the presence of B chromosomes and karyotype formula FC = 48m / sm + 2st / a + (5-10) B, as well as a new cytotype from the Amazon region, in Rhamphichthys sp. FC = 44m / sm + 6st / a, and also in R. marmoratus, FC = 46 + 4st / a in the state of Pará. The analysis of repetitive sequences in the new cytotypes demonstrated that probes 18S coincided with the regions of constriction secondary that are marked with silver nitrate in the classical NOR staining technique. The DNA probes 5S mark multiple sites, letting clear that the evolution of the ribosomal gene family is independent, at least in the genus Rhamphichthys. Retroelements REX1 and REX3 marked in a dispersed fashion throughout the genome, as already described in literature for other fishes. The REX1 element also marks the secondary constriction in R. rostratus, which has also been described in other species of fishes that inhabit polluted environments, exposed to environmental stresses and also in hybrid individuals. The barcoding DNA analysis allowed the construction of a Bayesian tree, which is in agreement with the cytogenetic data. Thus, populations of R. rostratus with and without B chromosomes are separate taxa. In turn, the sample from Mamirauá, herein called Rhamphichthys sp., since it was not been formally described, it is more similar in both karyotypic data as the barcoding analysis with R. hanni from southeastern Brazil. Our data let clear that the number of species in Rhamphichthys is underestimated, which reinforces the need for a taxonomic revision of the genus.
Acesso aberto (Open Access)
Vitrificação de tecido ovariano de gata doméstica (Felis catus): um modelo para a preservação da fertilidade em felinos silvestres
(Universidade Federal do Pará, 2016-09-06) BRITO, Danielle Cristina Calado de; SANTOS, Regiane Rodrigues dos; http://lattes.cnpq.br/0500967766886604; PIECZARKA, Julio Cesar; http://lattes.cnpq.br/6644368250823351
The aim o the present thesis was to develop an efficient vitrification protocol of the ovarian tissue from domestic cat (Felis catus). This study was divided: Phase I: Effect of different basis media during the vitrification of cat ovarian tissue; Phase II: Effect of different sugars (extracellular cryoprotectants) and the vitrification technique for the vitrification of feline ovarian tissue. In phase I, the morphology of preantral follicles was similar (p > 0.05) to fresh control when RPMI-1640 was used as basis medium for vitrification. RPMI-1640 does not contain phenol red, which was found to enhance ethylene glycol (EG) toxicity during vitrification. In phase 2, the percentage of morphologically normal preantral follicles was similar (p > 0.05) to fresh control only when the vitrification medium contained 0.1 or 0.5 M trehalose, instead of sucrose or raffinose at same concentrations. Furthermore, based on parameters such as morphology, cell proliferation and thickness of collagen fibers, it is possibe to assume that efficient vitrification of feline ovarian tissue can be performed by combining trehalose with EG, with or without dimethylsulfoxide (DMSO), applying the solid-surface vitrification (SSV) or ovarian tissue cryosystem (OTC) method. Although vitrification with OTC in the presence of EG did not differ from the other treatments, this protocol presented the highest percentages of preserved preantral follicles (56%), being similar to control (64%). Additionally, no effect on gene regulation was observed after vitrification when apoptosis markers (BAX – protein X associated to Bcl-2), endoplasmic reticulum (ER) stress (ER protein 29 – ERP29), water channels proteins like aquaporins 3 and 9 (AQP3 and AQP9), the membrane ABC transporters ABCB1 and ABCG2, except when the SSV method was applied using only EG as cryoprotectant followed by seven days in vitro culture, where ERP29 up-regulation (ER stress) and AQP9 down-regulation (impaired water transport) were observed. Based on this, it can be concluded that to efficiently preserve feline ovarian tissue, is is necessary the use of a vitrification protocol free of phenol red, supplemented with trehalose, as extracellular cryoprotectant, and EG alone or in combination with DMSO, as intracellular cryoprotectants. Both open (SSV) and closed (OTC) systems are equaly efficient to maintain follicular survival during the vitrification procedure.