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1.
Mol Genet Genomics ; 295(6): 1339-1353, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32601732

RESUMO

Transposable elements (TEs) are mobile DNA sequences that are able to move from one genomic location to another. These selfish elements are known as genomic parasites, since they hijack the host molecular machinery to generate new copies of themselves. The mobilization of TEs can be seen as a natural mutagen because new TE copies can insert into different loci and impact host genomic structure through different mechanisms. Although our knowledge about TEs is improving with new genomes available, there is still very limited data about the mobilome of species from the Coleoptera order, the most diverse order of insects, including species from the Scarabaeidae family. Therefore, the main goal of this study was to characterize the mobilome of D. (Luederwaldtinia) schiffleri, based on low-coverage genome sequencing, and reconstruct their evolutionary history. We used a combination of four different approaches for TE characterization and maximum likelihood phylogenetic analysis to study their evolution. We found a large and diverse mobilome composed of 38 TE superfamilies, 20 DNA transposon and 18 retrotransposons, accounting for 21% of the genome. Moreover, we found a number of incongruences between the TE and host phylogenetic trees in three DNA transposon TE superfamilies, which represents five TE families, suggesting possible horizontal transfer events between highly divergent taxa. In summary, we found an abundant and diverse mobilome and a number of horizontal transfer events that have shaped the evolutionary history of this species.


Assuntos
Besouros/genética , Elementos de DNA Transponíveis/genética , Evolução Molecular , Transferência Genética Horizontal , Genoma/genética , Filogenia , Animais
2.
Genet Mol Res ; 14(4): 15008-15, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26634462

RESUMO

In this study, fluorescence in situ hybridization (FISH) analysis was used to determine and compare the numbers and chromosomal locations of two multigene families (rDNA and histone H3) in four Neotropical species of gomphocerine grasshoppers. FISH using the 18S rDNA probe identified a single site on the S9 chromosome of Amblytropidia sp and Cauratettix borelli, a single site on chromosome M6 of Compsacris pulcher, and two sites (chromosomes L1 and L2) in Orphulella punctata. By contrast, FISH with a 5S rDNA probe identified dispersion of this sequence in the genomes of the four species, with evidence of intraspecific variations. Amblytropidia sp had six to eight FISH signals on autosomal chromosomes, while C. pulcher exhibited a signal only on the M5 bivalent. The histone H3 gene was less variable and was restricted to a single pair in all species. The conservation of the numbers and locations of 18S rDNA and H3 genes in conjunction with data from the literature was useful for evaluating karyotype evolution in this subfamily. The variation in the number and sizes of 5S rDNA sites indicates a process of recent dispersion that might have been mediated by transposition.


Assuntos
Gafanhotos/genética , Histonas/genética , Animais , Mapeamento Cromossômico , Evolução Molecular , Hibridização in Situ Fluorescente , Cariótipo , Masculino , Família Multigênica , RNA Ribossômico 18S/genética , RNA Ribossômico 5S/genética
3.
Genet Mol Res ; 11(3): 2432-40, 2012 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-22782627

RESUMO

Males of Zophobas aff. confusus and Nyctobates gigas (Tenebrionidae) collected in the State of Pernambuco, Brazil, were studied through conventional staining, C-banding, silver nitrate impregnation (AgNO3), and the base specific fluorochromes CMA3 and DAPI. Z. aff. confusus was found to have 2n = 20 (9+Xyp) while N. gigas exhibited 2n = 18 (8+neoXY). Large pericentromeric blocks of constitutive heterochromatin (CH) were detected throughout the autosomal complement of the two species, except in one autosomal pair of N. gigas in which no heterochromatic block was observed. The sex chromosomes of both species were almost totally heterochromatic. Double staining with CMA3/DA (distamycin) and DAPI/DA marked CH in Z. aff. confusus. However, DAPI staining was more intense. N. gigas was found to possess blocks of CH-positive CMA3 and homogeneous DAPI. AgNO3 staining also revealed differences between the two species. In Z. confusus an NOR was observed in the sexual bivalent Xyp and N. gigas was found to have an autosomal NOR.


Assuntos
Besouros/genética , Análise Citogenética , Animais , Bandeamento Cromossômico , Masculino , Meiose/genética , Metáfase/genética , Espermatogônias/citologia
4.
Cytogenet Genome Res ; 138(1): 46-55, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22797215

RESUMO

Repetitive DNA sequences constitute a high fraction of eukaryotic genomes and are considered a key component for the chromosome and karyotype evolution. For a better understanding of their evolutionary role in beetles, we examined the chromosomes of 5 species of the genus Coprophanaeus by C-banding, fluorochrome staining CMA3/DA/DAPI, and fluorescence in situ hybridization (FISH) with probes for 18S and 5S rRNA genes. The Coprophanaeus species have identical chromosome numbers and a conserved chromosome morphology. However, they show different sex chromosome forms, XY, Xy, XY(p), and heterochromatin seems to be involved in the origin and diversification of these forms. C-banding showed primarily the presence of diphasic chromosomes in all species examined. After CMA3/DA/DAPI staining, 1-9 autosomal pairs showed CMA3-positive blocks depending on the species, while DAPI-positive blocks were detected only in Coprophanaeusdardanus. FISH mapping revealed 5S rDNA signals in one autosomal pair in each species, whereas the number of pairs with 18S rDNA signals varied from 1-8 between the Coprophanaeus species. Our results suggest that distinct genetic mechanisms had been involved in the karyotype evolution of Coprophanaeus species, i.e. mechanisms maintaining the conserved number of 5S rDNA clusters and those generating variability in the amount of heterochromatin, sex chromosome forms, and distribution of 18S rDNA clusters.


Assuntos
Besouros/genética , Genes de RNAr , Heterocromatina , Família Multigênica , Cromossomos Sexuais , Animais , DNA Ribossômico/genética , Masculino
5.
Cytogenet Genome Res ; 134(2): 127-35, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21555878

RESUMO

Standard cytogenetic analyses and chromosomal mapping of the genes for 18S and 5S rRNAs and histone H3 were performed in 14 species of beetles of the genus Dichotomius (Coleoptera, Scarabaeidae, Scarabaeinae). Conserved karyotypes with 2n = 18 and biarmed chromosomes were observed in all species. Moreover, the presence of a large metacentric pair (pair 1) was characteristic in the studied species, evidencing a remarkable synapomorphy for this genus, which probably originated by an ancient fusion of 2 autosomes while the ancestral sex-chromosome pair remained conserved. FISH showed that the 5S rRNA and histone H3 genes are located in the proximal region of pair 2, with the 2 genes co-located. However, the major rDNA cluster probed by the 18S rRNA gene mapped to 1-3 bivalents, being exclusively autosomal, associated with sex elements, or both. In most species, the major rDNA cluster was observed in pair 3, and it was frequently (64.3%) located in the distal region regardless of the chromosome. The conserved number and position of the 5S rDNA/H3 histone cluster seems to be an ancient pattern shared by all of the studied species. In contrast, the major rDNA clusters apparently tolerate distinct patterns of diversification in the karyotypes of the species that could be associated with small inversions, ectopic recombination, and transposition. Moreover, we reinforced the association/co-localization between the 5S rRNA and histone H3 genes in this group contributing thus to the knowledge about the chromosomal organization and diversification patterns of multigene families in beetles and insects.


Assuntos
Besouros/genética , Histonas/genética , RNA Ribossômico/genética , Animais , Cromossomos de Insetos , Hibridização in Situ Fluorescente , Cariotipagem , Masculino
6.
Cytogenet Genome Res ; 132(1-2): 89-93, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20668370

RESUMO

This paper reports on the chromosomal location of 18S rRNA, 5S rRNA and H3 histone multigene families in 4 species of a relatively ancient and diversified group of grasshoppers belonging to the family Proscopiidae. The 5S rRNA and H3 histone genes were highly conserved in the number of sites and chromosomal position in the 4th chromosome pair in all species analyzed, whereas the 18S rRNA genes showed slightly more variation because they were present on one or 2 chromosome pairs, depending on the species. The 5S and 18S rRNA gene families occurred in different chromosomes; in contrast, H3 histone and 5S rRNA genes co-localized in the same chromosomal position, with an apparently interspersed organization. Considering that the Proscopiidae family is a relatively ancient group compared with the Acrididae family, the association of the H3 histone and 5S rRNA multigene families can represent a basal condition for grasshoppers, although more research is needed on other representatives of this insect group to confirm this statement. The presence of such an association of 5S rDNA and H3 histone in mussels and arthropods (beetles, grasshoppers and crustaceans) suggests that this linked configuration could represent an ancestral pattern for invertebrates. These results provide new insights into the understanding of the genome organization and the evolution of multigene families in grasshoppers and in insects as a whole.


Assuntos
Evolução Biológica , Gafanhotos/genética , Histonas/genética , Família Multigênica , RNA Ribossômico 18S/genética , RNA Ribossômico 5S/genética , Animais , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Especificidade da Espécie
7.
Environ Entomol ; 39(2): 359-67, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20388264

RESUMO

The aim of this study was to compare the dung beetle (Coleoptera, Scarabaeidae: Scarabaeinae) community structure at two sites in the Charles Darwin Ecological Refuge in Igarassu, Pernambuco, Brazil. Dung beetles were collected in 2006 using monthly samples from 48 pitfall traps baited with human dung and bovine carrion. The dung beetle communities from the study sites were compared in terms of abundance, species richness, and diversity (Shannon index). Seasonality was analyzed by Spearman correlation between rainfall data and community parameters. In total, 2,560 individuals belonging to 40 species, 16 genera, and 6 tribes were collected. Species richness was higher for the clear-cut area compared with the forest habitat. Estimators of species richness suggested a total richness of 42-47 species in the entire study area. A positive correlation was observed between monthly rainfall and total abundance of individuals for the clear-cut area but not for the forest habitat. This study contributes to a better understanding of Scarabaeinae ecology in the Atlantic rainforest of northeastern Brazil.


Assuntos
Biodiversidade , Besouros , Chuva , Animais , Brasil , Bovinos , Humanos , Clima Tropical
8.
Micron ; 41(2): 112-7, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19914839

RESUMO

Male mitotic and meiotic chromosomes of two species of the genus Deltochilum (Scarabaeidae) were analyzed through conventional staining, C-banding, base-specific fluorochromes, silver nitrate staining (AgNO(3)) and FISH (45S rDNA). The two species possessed karyotypes with 2n=14, neo-XY and meta-submetacentric chromosomes. The analysis of constitutive heterochromatin (CH) revealed mainly diphasic chromosomes in the two species, showing heterochromatic long arms. Silver nitrate staining labeled the blocks corresponding to CH in D. (Deltohyboma) aff morbillosum while in D. (Deltohyboma) calcaratum, AgNO(3) staining revealed only the CH blocks of the diphasic autosomes. The fluorochrome staining revealed in D. (D.) calcaratum the diphasic autosomes and the sex chromosomes with CMA(3)(+) blocks, and in D. (D.) aff morbillosum, the GC-rich sequences were restricted to the terminal regions of the long arms of the pairs 1 and 2 and the X. The FISH revealed 45S rDNA sites in two autosomic pairs and in the X chromosome. The analyses performed allowed for the identification of cytogenetic markers and the discussion of possible chromosome rearrangements that have been involved in the karyotypic differentiation of these species mainly related to the repetitive genome.


Assuntos
Besouros/genética , Diploide , Heterocromatina/genética , Animais , Análise Citogenética , Hibridização in Situ Fluorescente , Masculino
9.
Heredity (Edinb) ; 104(4): 393-400, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19756039

RESUMO

Chromosomal banding techniques and repetitive DNA mapping are useful tools in comparative analysis and in the elucidation of genome organization of several groups of eukaryotes. In this study, we contributed to the knowledge of Coleoptera genomes by reporting the chromosomal organization of repetitive DNA sequences, as well as the presence and characteristics of a B chromosome in two natural populations of Dichotomius geminatus (Coleoptera; Scarabaeidae) using classical, chromosomal banding and molecular cytogenetic techniques. As in other coleopteran species, the heterochromatin was mainly concentrated in pericentromeric regions and the B chromosome was composed almost entirely of heterochromatin. Physical mapping using double fluorescent in situ hybridization was performed for the first time in Coleoptera; using DNA probes for 5S and 18S ribosomal RNA (rRNA) and histone H3 genes, we showed that ribosomal 18S rDNAs are located in chromosomes 3 and 4, whereas 5S rRNA and histone H3 genes are colocalized in chromosomal pair 2 and show an apparently interspersed organization. Moreover, these genes are not present in the B chromosome, suggesting that the B chromosome did not originate from chromosomal pairs 2, 3 or 4. On the other hand, mapping of the C(0)t-1 DNA fraction showed that the B chromosome is enriched in repetitive DNA elements, also present in the standard complement, indicating an intraspecific origin of this element in D. geminatus. These results will contribute to our understanding of genome organization and evolution of repetitive elements in Coleoptera and other insects regarding both A and B chromosomes.


Assuntos
Cromossomos/genética , Besouros/genética , Histonas/genética , RNA Ribossômico 5S/genética , Sequências Repetitivas de Ácido Nucleico/genética , Animais , Bandeamento Cromossômico , Mapeamento Cromossômico/métodos , DNA/genética , Genes de Insetos , Ligação Genética/fisiologia , Genoma de Inseto , Masculino , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
10.
J Med Primatol ; 34(3): 156-62, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15860125

RESUMO

There are few papers about physiological indices in Callithrix penicillata, an increasing primate model in biomedicine. We investigated levels of plasmatic cortisol, plasmatic glucose, free fatty acids, blood cells, tympanic temperature, rectal temperature in C. penicllata, under a fast restraint. Measures of body and weight were accomplished. Males and females were not different regarding any measurements. Body measurements indicated differences between adults and juveniles. Adults showed higher hematocrit and a tendency for higher free fatty acids than juveniles. Right tympanic temperature was higher in adults than juveniles. This result suggests a higher reaction metabolism in adults than juveniles under a restraint stress. Due to the short-time of collecting the data, plasmatic cortisol did not influence physiological parameters. Therefore, we suggest that present results could be considered referential values of C. penicillata physiology.


Assuntos
Animais de Zoológico , Callithrix/fisiologia , Fatores Etários , Animais , Contagem de Células Sanguíneas , Glicemia , Temperatura Corporal , Peso Corporal , Brasil , Ácidos Graxos não Esterificados/metabolismo , Feminino , Hematócrito , Hidrocortisona/sangue , Masculino , Valores de Referência , Fatores Sexuais
11.
Braz. j. infect. dis ; 8(6): 465-468, Dec. 2004. ilus
Artigo em Inglês | LILACS | ID: lil-401722

RESUMO

Tungiasis is caused by the penetration of the female sand flea Tunga penetrans into the epidermis, and subsequent hypertrophy of the parasite. In most cases lesions are confined to the feet. During a cross-sectional study, an unusual case of ectopic tungiasis in the inguinal area was detected. Histological examination of tissue samples showed a remarkable pseudoepitheliomatous aspect of the epidermis. Clinical features and differential diagnoses are discussed.


Assuntos
Humanos , Animais , Feminino , Criança , Ectoparasitoses/parasitologia , Linfonodos/parasitologia , Sifonápteros , Antinematódeos/uso terapêutico , Estudos Transversais , Ectoparasitoses/tratamento farmacológico , Ectoparasitoses/patologia , Hiperplasia/tratamento farmacológico , Hiperplasia/parasitologia , Hiperplasia/patologia , Tiabendazol/uso terapêutico
12.
Braz J Infect Dis ; 8(6): 465-8, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15880239

RESUMO

Tungiasis is caused by the penetration of the female sand flea Tunga penetrans into the epidermis, and subsequent hypertrophy of the parasite. In most cases lesions are confined to the feet. During a cross-sectional study, an unusual case of ectopic tungiasis in the inguinal area was detected. Histological examination of tissue samples showed a remarkable pseudoepitheliomatous aspect of the epidermis. Clinical features and differential diagnoses are discussed.


Assuntos
Ectoparasitoses/parasitologia , Linfonodos/parasitologia , Sifonápteros , Animais , Antinematódeos/uso terapêutico , Criança , Estudos Transversais , Ectoparasitoses/tratamento farmacológico , Ectoparasitoses/patologia , Feminino , Humanos , Hiperplasia/tratamento farmacológico , Hiperplasia/parasitologia , Hiperplasia/patologia , Tiabendazol/uso terapêutico
13.
Eur Urol ; 38(6): 774-7, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11111200

RESUMO

OBJECTIVES: Lymphoma is the most frequent testicular malignancy in men over 60 years of age. Even though patients present initially with localized disease, the high incidence of bilateral involvement, synchronous or not, and early systemic dissemination are characteristic of these neoplasms. Sometimes the interval between tumor involvement of both testes is long. The question is raised whether either the patient has a predisposition to present new clones of transformed lymphocytes, or the same disease using the same pathway from a systemic reservoir infiltrates the contralateral testis. METHOD: Polymerase chain reaction and DNA sequencing were used to detect immunoglobulin heavy chain (IgH) rearrangement in paraffin-embedded specimens from asynchronous tumors affecting the right and left testis of a 85-year-old man with an interval period of 13 months. RESULTS: Both tumors showed the same IgH rearrangement. CONCLUSIONS: The lymphoma affecting the left and right testis derived from the same clone. It makes a strong case that lymphoma of the testis is the first manifestation of a systemic disease and should be treated aggressively early at the beginning of the disease.


Assuntos
Linfoma Difuso de Grandes Células B/genética , Neoplasias Testiculares/genética , Idoso , Idoso de 80 Anos ou mais , DNA de Neoplasias/química , Humanos , Cadeias Pesadas de Imunoglobulinas/química , Linfoma Difuso de Grandes Células B/patologia , Masculino , Reação em Cadeia da Polimerase , Neoplasias Testiculares/patologia , Testículo/patologia , Fatores de Tempo
14.
Cornea ; 17(5): 522-8, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9756447

RESUMO

PURPOSE: To compare the reproducibility of computerized videokeratoscopy systems by using normal eyes and calibrated objects. METHODS: We evaluated the reproducibility of three commercially available videokeratoscopes [EyeSys, TechnoMed C-Scan, and PAR Corneal Topography System (CTS)] with the manual keratometer (Bausch & Lomb) by using calibration spheres and 10 normal subjects (20 eyes). All videokeratoscopy and keratometer results were obtained by one investigator (R.M.). Each eye and calibration sphere were submitted to 10 serial examinations by using each system. The average K of all points within the central 3.0 mm of the topography systems (central 3.0 mm) was compared with the average K of the manual keratometer. RESULTS: All videokeratoscopy systems correlated well with each other and manual keratometry when accessing aspheric and spherocylinder calibration balls. EyeSys central keratometry clinical results had the strongest correlation with the average keratometry results at 35%, followed by PAR-CTS at 25% and C-Scan at 5%. Among the videokeratoscopy units, EyeSys and PAR-CTS had the strongest correlation at 65%. The correlation between the TechnoMed C-Scan and both the EyeSys and PAR-CTS systems was 25%. There was a statistically significant difference (p < 0.05) between the systems when analyzing the results obtained from clinical subjects. The average keratometry (K) difference of human eyes between videokeratoscopy systems is <0.35 diopters (D) (p < 0.05), which may be clinically significant. The average manual K reading (42.97 D) is statistically significantly flatter (p < 0.05) than each of the videokeratoscopy units (EyeSys = 43.49 D; PAR = 43.48 D; C-Scan = 43.83 D). Comparing the 10 measurements of each eye or calibration object in the same videokeratoscopy system verified that the devices give reproducible results. The average standard deviation (ASD) of the keratometer was 0.10 D. The ASD of the videokeratoscopy units was 0.05 D for the EyeSys, 0.29 D for the PAR-CTS, and 0.31 D for the C-Scan systems. CONCLUSION: Based on this study, we should not assume that the results of different topography systems can be interchanged in clinical studies.


Assuntos
Córnea/anatomia & histologia , Topografia da Córnea/normas , Topografia da Córnea/instrumentação , Humanos , Modelos Anatômicos , Reprodutibilidade dos Testes
16.
Rev. Soc. Bras. Med. Trop ; 17(1): 37-40, 1984.
Artigo em Português | LILACS | ID: lil-23996

RESUMO

Um caso de hepatite de Labrea nos possibilitou um estudo do comportamento dos fatores da coagulao nessa doenca. O objetivo principal foi estudar a coagulacao do sangue, visando: 1. conhecer os niveis dos fatores da coagulacao na febre negra 2.contribuir para o melhor conhecimento da doenca, principalmente no que se refere as manifestacoes de hemorragia; 3. tentar correlacionar a gravidade do quadro clinico e prognostico a intensidade das alteracoes dos fatores da coagulacao.Os resultados evidenciaram uma alteracao acentuada da crase sanguinea, sugerindo que, alem do quadro infeccioso, o paciente desenvolveu, igualmente, uma sindrome de coagulacao intravascular disseminada


Assuntos
Pré-Escolar , Humanos , Masculino , Coagulação Sanguínea , Leishmaniose Visceral
17.
Artigo em Português | LILACS | ID: lil-20265

RESUMO

O nivel em que a veia axiliar cruza a sua face posterior e se torna a veia subclavia foi observado em 40 disseccoes. Foram feitas varias medidas de interesse pratico obtendo-se as seguintes medias: 1. Comprimento da clavicula: 15,41 cm. 2.Distancia do ponto de transicao da veia axilar para veia subclavia (o ponto da pesquisa) a articulacao esternoclavicular: 5,1 cm. 3. Diametro da veia e da arteria no nivel de pesquisa: 1,5 cm e 0,8 cm respesctivamente. 4. Espessura do m.subclavio neste nivel: 5,4 mm. 5. Distancia entre a veia subclavia e o bordo medial da primeira costela: 1,3 cm. 6. Angulo entre a clavicula e a veia subclavia: 47 graus


Assuntos
Adulto , Humanos , Masculino , Feminino , Veia Axilar , Veia Subclávia
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