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1.
Environ Technol ; 40(1): 11-18, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28891384

RESUMO

The role of Eichhornia crassipes for removing pollutants from low strength sewage was evaluated in three pilot-scale constructed wetlands (CW): CW 1, planted with E. crassipes in a filter media; CW 2, unplanted, composed by filter media; and CW 3, composed by E. crassipes floating on the sewage. The operation was divided into three stages by varying the nominal hydraulic retention time into: (I) 24 h; (II) 48 h; (III) 72 h. Temporal sampling profiles were carried out with collection of the influent and effluent samples to determine temperature, pH, chemical oxygen demand (COD), TKN and TP. Contents of TP and TN were analyzed in the plant tissue of the macrophyte. The best removal efficiency rates for phosphorus (38%) and TKN (47%) were obtained in CW 3 for 72 h. The highest COD removal was observed in the CW 2 (80%) for 48 h. The macrophyte E. crassipes contributed to the absorption process with uptake rate percentages of 8.3% (CW 1) and 9.0% (CW 3) for TN and 0.78% (CW 1) and 1.56% (CW 3) for TP on the dry matter of the plant. The chosen species planted in the systems contributed to the achievement of higher nutrient removal.


Assuntos
Esgotos , Áreas Alagadas , Biodegradação Ambiental , Nitrogênio , Nutrientes , Fósforo , Eliminação de Resíduos Líquidos
2.
Chromosoma ; 127(2): 269-278, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29372309

RESUMO

Heteromorphic sex chromosomes are common in eukaryotes and largely ubiquitous in birds and mammals. The largest number of multiple sex chromosomes in vertebrates known today is found in the monotreme platypus (Ornithorhynchus anatinus, 2n = 52) which exhibits precisely 10 sex chromosomes. Interestingly, fish, amphibians, and reptiles have sex determination mechanisms that do or do not involve morphologically differentiated sex chromosomes. Relatively few amphibian species carry heteromorphic sex chromosomes, and when present, they are frequently represented by only one pair, either XX:XY or ZZ:ZW types. Here, in contrast, with several evidences, from classical and molecular cytogenetic analyses, we found 12 sex chromosomes in a Brazilian population of the smoky jungle frog, designated as Leptodactylus pentadactylus Laurenti, 1768 (Leptodactylinae), which has a karyotype with 2n = 22 chromosomes. Males exhibited an astonishing stable ring-shaped meiotic chain composed of six X and six Y chromosomes. The number of sex chromosomes is larger than the number of autosomes found, and these data represent the largest number of multiple sex chromosomes ever found among vertebrate species. Additionally, sequence and karyotype variation data suggest that this species may represent a complex of species, in which the chromosomal rearrangements may possibly have played an important role in the evolution process.


Assuntos
Anuros/genética , Processos de Determinação Sexual , Cromossomo X/metabolismo , Cromossomo Y/metabolismo , Animais , Anuros/classificação , Brasil , Hibridização Genômica Comparativa , Feminino , Hibridização in Situ Fluorescente , Cariótipo , Cariotipagem , Masculino , Filogenia , Cromossomo X/ultraestrutura , Cromossomo Y/ultraestrutura
4.
Chromosoma ; 124(3): 353-65, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25605041

RESUMO

Sex chromosomes have evolved many times from morphologically identical autosome pairs, most often presenting several recombination suppression events, followed by accumulation of repetitive DNA sequences. In Orthoptera, most species have an X0♂ sex chromosome system. However, in the subfamily Melanoplinae, derived variants of neo-sex chromosomes (neo-XY♂ or neo-X1X2Y♂) emerged several times. Here, we examined the differentiation of neo-sex chromosomes in a Melanoplinae species with a neo-XY♂/XX♀ system, Ronderosia bergi, using several approaches: (i) classical cytogenetic analysis, (ii) mapping via fluorescent in situ hybridization of some selected repetitive DNA sequences and microdissected sex chromosomes, and (iii) immunolocalization of distinct histone modifications. The microdissected sex chromosomes were also used as sources for Polymerase chain reaction (PCR) amplification of RNA-coding multigene families, to study variants related to the sex chromosomes. Our data suggest that the R. bergi neo-Y has become differentiated after its formation by a Robertsonian translocation and inversions, and has accumulated repetitive DNA sequences. Interestingly, the ex autosomes incorporated into the neo-sex chromosomes retain some autosomal post-translational histone modifications, at least in metaphase I, suggesting that the establishment of functional modifications in neo-sex chromosomes is slower than their sequence differentiation.


Assuntos
Evolução Molecular , Gafanhotos/genética , Cromossomos Sexuais , Animais , Feminino , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Filogenia
5.
Heredity (Edinb) ; 114(2): 207-19, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25248465

RESUMO

The spliceosome, constituted by a protein set associated with small nuclear RNA (snRNA), is responsible for mRNA maturation through intron removal. Among snRNA genes, U1 is generally a conserved repetitive sequence. To unveil the chromosomal/genomic dynamics of this multigene family in grasshoppers, we mapped U1 genes by fluorescence in situ hybridization in 70 species belonging to the families Proscopiidae, Pyrgomorphidae, Ommexechidae, Romaleidae and Acrididae. Evident clusters were observed in all species, indicating that, at least, some U1 repeats are tandemly arrayed. High conservation was observed in the first four families, with most species carrying a single U1 cluster, frequently located in the third or fourth longest autosome. By contrast, extensive variation was observed among Acrididae, from a single chromosome pair carrying U1 to all chromosome pairs carrying it, with occasional occurrence of two or more clusters in the same chromosome. DNA sequence analysis in Eyprepocnemis plorans (species carrying U1 clusters on seven different chromosome pairs) and Locusta migratoria (carrying U1 in a single chromosome pair) supported the coexistence of functional and pseudogenic lineages. One of these pseudogenic lineages was truncated in the same nucleotide position in both species, suggesting that it was present in a common ancestor to both species. At least in E. plorans, this U1 snDNA pseudogenic lineage was associated with 5S rDNA and short interspersed elements (SINE)-like mobile elements. Given that we conclude in grasshoppers that the U1 snDNA had evolved under the birth-and-death model and that its intragenomic spread might be related with mobile elements.


Assuntos
Genoma de Inseto , Gafanhotos/genética , Família Multigênica , Ribonucleoproteína Nuclear Pequena U1/genética , Animais , Evolução Biológica , Mapeamento Cromossômico , Cromossomos , Sequência Conservada , Feminino , Masculino , Dados de Sequência Molecular
6.
An Sist Sanit Navar ; 36(1): 145-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23648507

RESUMO

Gastric lipoma is considered a rare condition that may constitute a challenging diagnosis. A 51-year-old woman presented dysphagia and abdominal pain, and an upper digestive endoscopic study disclosed a gastric tumor located in the submucosa of the pyloric antrum. Conclusive diagnosis was established after repeated endoscopic biopsies, and the patient was subjected to an atypical gastrectomy, which evolved into a pyloric stenosis. This complication was appropriately corrected and the patient remains symptomless, under outpatient surveillance.


Assuntos
Gastrectomia/efeitos adversos , Lipoma/cirurgia , Estenose Pilórica/etiologia , Neoplasias Gástricas/cirurgia , Feminino , Humanos , Pessoa de Meia-Idade , Estenose Pilórica/cirurgia
7.
Transplant Proc ; 44(8): 2391-3, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23026602

RESUMO

Nonadherence to immunosuppressive medications represents a burden to organ transplantation being associated with rejection episodes and graft loss. In this cross-sectional study we evaluated the prevalence and risk factors for nonadherence in kidney transplant patients by measuring the retrieval of the immunosuppressive drugs in the registry kept by the state Rio Grande do Sul public health system. We considered nonadherence the failure to retrieval of medication at least one time over a 1-year period of evaluation. In 288 patients evaluated, the frequency of failure to retrieve was 58.7%. Being fully employed (66.4% × 33.6%, P = .008) and younger age at transplantation (39 ± 13 × 46 ± 11, P = .011) were associated with nonadherence. Multivariate analysis showed a greater prevalence ratio (PR) of non- adherence in patients using tacrolimus. Estimated glomerular filtration rate was significantly lower in the nonadherence groups as compared with adherent groups (45.3 ± 21.6 × 51.3 ± 19.4, P = .016). In conclusion, we found a high prevalence of nonadherence to immunosuppressive drugs with association to active working situation and use of tacrolimus. Importantly, glomerular filtration rate was found to be lower in nonadherent patients.


Assuntos
Rejeição de Enxerto/prevenção & controle , Sobrevivência de Enxerto/efeitos dos fármacos , Imunossupressores/uso terapêutico , Transplante de Rim/imunologia , Adesão à Medicação , Adulto , Fatores Etários , Brasil , Estudos Transversais , Emprego , Feminino , Taxa de Filtração Glomerular/efeitos dos fármacos , Rejeição de Enxerto/imunologia , Rejeição de Enxerto/fisiopatologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Sistema de Registros , Medição de Risco , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
8.
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
9.
Comp Cytogenet ; 6(2): 163-81, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-24260660

RESUMO

Cichlids represent one of the most species-rich families of fishes and have attracted the attention of evolutionary biologists due to the rapid radiation occurring in some groups and the importance of some species in the world aquaculture. Cytogenetic analysis was conducted in 10 cichlid species from the Araguaia River, Amazon Basin, Brazil. The chromosome number was 2n=48 for all analyzed species except for Laetacara araguaiae Ottoni et Costa, 2009 (2n=44). Chromosomal polymorphism was detected only in Geophagus proximus (Castelnau, 1855), which exhibits an extra large submetacentric and and a dot-like chromosomes. Moreover, the C-banding revealed a general pericentromeric heterochromatic pattern and some additional blocks for some species. The heterochromatic blocks corresponding to AgNOR bearing regions were observed in all species and also corresponded to CMA3 positive blocks, which were observed in terminal regions. Besides the general conserved chromosomal and heterochromatin patterns for South American cichlids, the presence of GC-rich heterochromatin was quite different in the species Biotodoma cupido (Heckel, 1840), Geophagus proximus, Retroculus lapidifer (Castelnau, 1855), Crenicichla strigata Günther, 1862 and Heros efasciatus Heckel, 1840. The results suggest that independent events of heterochromatin modification occurred during chromosome evolution in the group, regardless of the conservation of macro-chromosomal structure.

10.
Cytogenet Genome Res ; 135(2): 111-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21893968

RESUMO

Phosphorylation of serine 10 in histone H3 (H3S10ph) has been extensively analyzed and appears to be a conserved chromatin change associated with chromosome condensation in different eukaryotic organisms. In this work, we report the distribution of H3S10ph during meiosis in monocentric and holokinetic chromosomes of 6 insect species and in mitotic chromosomes of 7 mammalian species, aiming to investigate the labeling patterns in phylogenetically distant groups. The results indicated a very similar phosphorylation timing and distribution pattern among insects. The sex chromosomes of insects analyzed were always undercondensed and hypophosphorylated. Similarly, the micro chromosomes of the bug Pachylis aff pharaonis were also undercondensed and hypophosphorylated. Holokinetic chromosomes of bugs and monocentric chromosomes of grasshoppers and beetles displayed identical phosphorylation pattern in spite of the difference in the centromere type. Among mammals, a uniform chromosome phosphorylation was observed in marsupials, whereas bat chromosomes displayed a longitudinal banding pattern. These data indicate that, in general, the intensity of H3S10 phosphorylation in animal chromosomes is variable among the distinct chromosome types and associated with the degree of chromatin condensation at metaphase, but it may vary between different groups of animals.


Assuntos
Cromossomos de Insetos/metabolismo , Cromossomos de Mamíferos/metabolismo , Histonas/metabolismo , Serina/metabolismo , Animais , Quirópteros , Cromatina/genética , Cromatina/metabolismo , Cromossomos de Insetos/genética , Cromossomos de Mamíferos/genética , Besouros , Gafanhotos , Meiose/genética , Metáfase/genética , Mitose/genética , Gambás , Fosforilação , Especificidade da Espécie
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