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1.
Genet Mol Biol ; 47(4): e20230339, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39264098

RESUMO

Down syndrome (DS), affecting 1 in 700 live births, is the most prevalent chromosomal disorder among newborns. Recognizable by classical clinical features, patients with DS are susceptible to various immunological misbalances. Inflammasome is (mis)activated in several immune-mediated diseases, however studies on individuals with DS are lacking. The present study evaluated the gene expression of NLRP1, NLRP3 and IL-1ß in individuals with DS, aiming to understand their susceptibility to immune-mediated diseases. In addition, we assessed whether the individuals with DS present a differential inflammatory response after in vitro infection using PBMCs. For the gene expression assay, 20 individuals with DS and 15 healthy individuals for the control group (CT) were included, while the in vitro infection assay included 10 subjects. mRNA levels from individuals with DS group showed 1.9-fold change (FC) downregulation for NLRP1 (p=0.0001), but no differences for NLRP3 and IL1ß. We did not observe significant differences between lipopolysaccharide (LPS)-treated and untreated cells in our in vitro assays. The differential expression of NLRP1 in individuals with DS suggests a potential association with susceptibility to the development of immune-mediated diseases, but further analysis is needed to confirm this relationship.

2.
Drug Chem Toxicol ; 46(1): 104-112, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34906022

RESUMO

Amburana cearensis leaves have been used in folk medicine to treat respiratory diseases and inflammations. This study aimed to evaluate the biological potential of A. cearensis leaves by antioxidant and in vitro cytogenotoxic analyses of ethanolic crude extract (EE) and its fractions in healthy human cells. The EE was obtained by percolation, followed by fractionation using dichloromethane, cyclohexane, ethyl acetate (EtOAc), and methanol (MeOH) as organic solvents. Extract and all fractions were evaluated for their antioxidant potential by DPPH and reducing power tests. In vitro cytotoxic activity was determined in human peripheral blood mononuclear cells by MTT assay for the extract, EtOAc and MeOH fractions. In turn, the genotoxic activity was determined in human lymphocytes by the Cytokinesis Block Micronucleus assay only for the EtOAc fraction. Only EtOAc fraction was analyzed via gas chromatography coupled to mass spectrometry due to its higher biological activity. Considering the antioxidant potential, the EtOAc fraction was most effective in DPPH (EC50 43.37 µg/mL) and reducing power (EC50 89.80 µg/mL) assays. GC-MS analysis of the EtOAc fraction led to the identification of guaiacol, 2,3-dihydro-benzofuran, 2-methoxy-4-vinylphenol, isovanillic acid methyl ester, 4-hydroxybenzaldehyde, and 4-(ethoxymethyl)-phenol. The EE (400-1000 µg/mL), EtOAc (≤150 µg/mL) and MeOH (50 and 150-600 µg/mL) fractions were not cytotoxic by MTT test. Additionally, the EtOAc fraction (100-400 µg/mL) did not induce significant genotoxic damage. Concentrations of the EtOAc fraction with antioxidant activity showed no cytotoxicity, nor genotoxicity potential, indicating them as a nontoxic natural antioxidant source.


Assuntos
Antioxidantes , Fabaceae , Humanos , Antioxidantes/farmacologia , Antioxidantes/química , Extratos Vegetais/toxicidade , Extratos Vegetais/química , Leucócitos Mononucleares , Cromatografia Gasosa-Espectrometria de Massas
3.
Cytogenet Genome Res ; 161(12): 569-577, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35093945

RESUMO

The subfamily Lonchorhininae encompasses 6 species of sword-nosed bats (Lonchorhina) and is one of the most problematic lineages in the Neotropical leaf-nosed bats (Phyllostomidae) phylogeny. There are at least 5 different hypotheses to explain when the subfamily diverged from the remaining phyllostomids, but none with robust statistical support. Here, we generated a chromosome painting homology map of Lonchorhina aurita karyotype (2n = 32 and FN = 60) using whole-chromosome probes of Macrotus californicus (MCA; 2n = 40 and FN = 60). We placed the karyotype changes of L. aurita in a phylogenetic context to discuss the most likely branching position of Lonchorhininae based on karyotypic evolution. We show that L. aurita has a derived karyotype with 24 segments homologous to the 20 MCA chromosomes used as probes. Comparative analyses between 7 published painted bats species across 4 phyllostomid subfamilies (Macrotinae, Phyllostominae, Glossophaginae, and Lonchophyllinae) revealed that one inversion (MCA 4inv) and one fusion (MCA 17 + 18) are shared derived features between the karyotypes of L. aurita and species of Phyllostominae not yet observed in other bats. Our data show that chromosomal homology maps may contribute with new insights into a long-standing phylogenetic debate that has endured for decades.


Assuntos
Quirópteros/classificação , Quirópteros/genética , Coloração Cromossômica , Evolução Molecular , Filogenia , Animais , Feminino , Cariótipo , Cariotipagem , Masculino
4.
Genet Mol Biol ; 43(1): e20180370, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32105287

RESUMO

Biological dosimetry aims to estimate individual absorbed doses due ionizing radiation exposure. The dicentric chromosomes are considered the most specific biomarker for dose estimation. This study aimed to compare calibration curves for linear low energy transfer (LET) radiation built from low dose rates and whether they vary in terms of dose estimation. For that we did a search in the literature of all calibration curves produced with low dose rates and we simulated the dose estimation from pre-established dicentric's frequencies. The information on methodologies and cytogenetic results of each study were analyzed. As expected dose rate influence ß coefficients, especially at higher doses. However, we have seen that some doses were not statistically different but they should be, because there is a significant association between the productions of dicentrics and dose rate. This comparative study reinforced the robustness of the dicentric assay and its importance in biological dosimetry. We also emphasized that the dose rate was an important factor in dose estimations. Thus, intercomparison exercises should take into account the dose rates of the participating laboratories, because the dose rates might explain why some results of estimated doses fall outside the recommendations.

5.
Chromosome Res ; 25(3-4): 313-325, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28916913

RESUMO

Despite their ubiquitous incidence, little is known about the chromosomal distribution of long interspersed elements (LINEs) in mammalian genomes. Phyllostomid bats, characterized by lineages with distinct trends of chromosomal evolution coupled with remarkable ecological and taxonomic diversity, represent good models to understand how these repetitive sequences contribute to the evolution of genome architecture and its link to lineage diversification. To test the hypothesis that LINE-1 sequences were important modifiers of bat genome architecture, we characterized the distribution of LINE-1-derived sequences on genomes of 13 phyllostomid species within a phylogenetic framework. We found massive accumulation of LINE-1 elements in the centromeres of most species: a rare phenomenon on mammalian genomes. We hypothesize that expansion of these elements has occurred early in the radiation of phyllostomids and recurred episodically. LINE-1 expansions on centromeric heterochromatin probably spurred chromosomal change before the radiation of phyllostomids into the extant 11 subfamilies and contributed to the high degree of karyotypic variation observed among different lineages. Understanding centromere architecture in a variety of taxa promises to explain how lineage-specific changes on centromere structure can contribute to karyotypic diversity while not disrupting functional constraints for proper cell division.


Assuntos
Centrômero/genética , Quirópteros/genética , Cromossomos de Mamíferos , Evolução Molecular , Elementos Nucleotídeos Longos e Dispersos , Animais , Heterocromatina , Hibridização in Situ Fluorescente , Cariótipo , Filogenia , Sequências Repetitivas de Ácido Nucleico , Retroelementos , Análise de Sequência de DNA
6.
Clin Oral Investig ; 22(7): 2553-2558, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29404812

RESUMO

OBJECTIVES: This in vivo research investigated whether pulp treatments using formocresol for 7 days would cause mutagenic changes in children's lymphocytes. MATERIALS AND METHODS: The mutagenicity was tested in lymphocyte cultures established from the peripheral blood of children living in Brazil. The samples consisted of 2000 cells from teeth undergoing formocresol pulpotomies in which the formocresol pellet was sealed in the primary tooth for 7 days. It was removed on the seventh day, the base was placed, and the tooth was restored. Two venous blood samples (6-8 ml) were collected from each child; the first was prior to pulp therapy, and the second was 7 days later. Two thousand metaphases were analyzed. The level of significance adopted for the statistics was P < 0.05, and a random effects meta-analysis was performed combining this and two previous studies. RESULTS: There was no significant difference found in the metaphase analysis between the blood samples taken before and after the pulpotomy treatment (Wilcoxon signed rank test); however, the meta-analysis showed a significant difference between the combined studies. CONCLUSIONS: This study did not reveal any mutagenic effects, but based on the combined meta-analysis, we recommend the careful use of formocresol. CLINICAL RELEVANCE: This research helps to bring scientific evidence of the safe use of formocresol in deciduous pulpotomy treatments.


Assuntos
Polpa Dentária/efeitos dos fármacos , Formocresóis/toxicidade , Linfócitos/efeitos dos fármacos , Pulpotomia , Brasil , Células Cultivadas , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Testes de Mutagenicidade , Dente Decíduo
7.
Genet Mol Biol ; 41(4): 727-734, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30508004

RESUMO

Turner syndrome (TS) is characterized by a set of clinical conditions, including autoimmune/inflammatory diseases and infectious conditions, that can compromise a patient's quality of life. Here we assessed polymorphisms in CTLA-4 +49A/G (rs231775), PTPN22 +1858G/A (rs2476601), and MBL2 -550 (H/L) (rs11003125), -221(X/Y) (rs7096206) and exon 1 (A/O) in women from northeastern Brazil to determine whether polymorphisms within these key immune response genes confer differential susceptibility to clinical conditions in TS. A case-control genetic association study was performed, including 86 female TS patients and 179 healthy women. An association was observed for the A/G genotype of CTLA-4 +49A/G in TS patients (p=0.043, odds ratio [OR]=0.54). In addition, an association between the CTLA-4 G/G genotype and obesity was detected in TS patients (p=0.02, OR=6.04). Regarding, the -550(H/L) polymorphism in the MBL2 promoter, the frequency of the H/L genotype was significantly higher in the TS group than healthy controls (p=0.01, OR=1.96). The H/H genotype indicated a protective effect in TS patients (p=0.01, OR=0.23). No differences were observed in the distribution of -221(X/Y), MBL2 exon 1 variants, and PTPN22 +1858G/A in any assessed groups. CTLA-4 variants are potentially involved in obesity in this cohort of TS patients from northeastern Brazil.

8.
Cytogenet Genome Res ; 152(4): 213-221, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28992625

RESUMO

B chromosomes, extra elements present in the karyotypes of some eukaryote species, have been described in the grasshopper Xyleus discoideus angulatus. Although some studies have proposed an autosomal origin of the B chromosome in X. d. angulatus, little is known about its repetitive DNA composition and evolutionary dynamics. The aim of the present work was to shed light on the B chromosome evolution in X. d. angulatus by cytogenetic analysis of 27 populations from Pernambuco and Ceará states (Brazil). The frequency of B chromosomes in the different populations was determined, and chromosome measurements and fluorescence in situ hybridization (FISH) with C0t-DNA and telomeric and B chromosome sequences were performed in cells from B-carrying individuals. The results revealed variations in B chromosome prevalence among the populations and showed that some B chromosomes were smaller in certain populations. FISH produced similar patterns for the C0t-DNA probe in all hybridized individuals, whereas telomeric and B chromosome probes, obtained by microdissection, exhibited variations in their distribution. These results indicate the presence of 3 morphotypes of B chromosomes in X. d. angulatus, with variation in repetitive DNA composition during their evolution. In this species, B chromosomes have an intraspecific origin and probably arose from the pericentromeric region of A chromosomes.


Assuntos
Gafanhotos/genética , Animais , Brasil , Centrômero/genética , Mapeamento Cromossômico , Cromossomos/genética , DNA/genética , Evolução Molecular , Variação Genética , Genética Populacional , Genoma de Inseto , Hibridização in Situ Fluorescente , Cariotipagem , Sequências Repetitivas de Ácido Nucleico , Telômero/genética , Cromossomo X/genética
9.
Caries Res ; 51(1): 46-51, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27992873

RESUMO

This work aimed to further evaluate the association of MMP20 rs1784418 C>T and dental caries experience with the hypothesis that MMP20 rs1784418 C>T is a risk factor for dental caries. 184 children 4-7 years of age had their caries experience determined and buccal cheek swabs collected for DNA extraction to test for association with the MMP20 rs1784418 C>T using standard statistical approaches. A meta-analytic approach was also implemented to compile previous discrepant reports of the same association. We found an association between MMP20 rs1784418 C>T and dental caries experience in primary dentition (p = 0.01). The meta-analysis showed that this association appears to favor individuals born in Brazil and not Turkey. MMP20 rs1784418 C>T appears to protect against dental caries, but its effects are likely to be more marked in certain populations.


Assuntos
Cárie Dentária/etnologia , Cárie Dentária/genética , Predisposição Genética para Doença/etnologia , Metaloproteinase 20 da Matriz/genética , Brasil/etnologia , Criança , Pré-Escolar , Estudos Transversais , Índice CPO , Demografia , Técnicas de Genotipagem , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Dente Decíduo , Turquia/etnologia
10.
Am J Med Genet A ; 167(7): 1510-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25858821

RESUMO

Folate metabolism dysfunction can lead to DNA hypomethylation and abnormal chromosomal segregation. Previous investigations of this association have produced controversial results. Here we performed a case-control study in patients with Turner syndrome (TS) to determine the effects of genetic polymorphisms of folate pathway genes as potential risk factors for somatic chromosomal nondisjunction. TS is a useful model for this investigation because patients with TS show a high frequency of chromosome mosaicism. Here we investigated the possible association of polymorphisms of the MTHFR gene with TS risk, which has been previously investigated with controversial results. We also examined the effects of MTR, RFC1, and TYMS gene polymorphisms in TS for the first time. The risk was evaluated according to allelic and genotype (independent and combined) frequencies among 70 patients with TS and 144 age-matched healthy control subjects. Polymorphism genotyping was performed by PCR, PCR-RFLP, and PCR-ASA. The polymorphisms MTHFR 677C>T and 1298A>C, MTR 2756A>G, RFC1 80G>A, and TYMS 2R/3R-alone or in combinations-were not associated with the risk of chromosomal aneuploidy in TS. In conclusion, our present findings did not support a link between impaired folate metabolism and abnormal chromosome segregation leading to somatic nondisjunction in TS patients.


Assuntos
Ácido Fólico/metabolismo , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Não Disjunção Genética/fisiologia , Polimorfismo Genético/genética , Transdução de Sinais/genética , Síndrome de Turner/genética , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Estudos Transversais , Análise Citogenética , Genótipo , Humanos , Modelos Logísticos , Não Disjunção Genética/genética , Razão de Chances , Mutação Puntual/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Proteína de Replicação C/genética , Fatores de Risco , Timidilato Sintase/genética
11.
Genetica ; 142(1): 49-58, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24368540

RESUMO

Chromosomal organization and the evolution of genome architecture can be investigated by physical mapping of the genes for 45S and 5S ribosomal DNAs (rDNAs) and by the analysis of telomeric sequences. We studied 12 species of bats belonging to four subfamilies of the family Phyllostomidae in order to correlate patterns of distribution of heterochromatin and the multigene families for rDNA. The number of clusters for 45S gene ranged from one to three pairs, with exclusively location in autosomes, except for Carollia perspicillata that had in X chromosome. The 5S gene all the species studied had only one site located on an autosomal pair. In no species the 45S and 5S genes collocated. The fluorescence in situ hybridization (FISH) probe for telomeric sequences revealed fluorescence on all telomeres in all species, except in Carollia perspicillata. Non-telomeric sites in the pericentromeric region of the chromosomes were observed in most species, ranged from one to 12 pairs. Most interstitial telomeric sequences were coincident with heterochromatic regions. The results obtained in the present work indicate that different evolutionary mechanisms are acting in Phyllostomidae genome architecture, as well as the occurrence of Robertsonian fusion during the chromosomal evolution of bats without a loss of telomeric sequences. These data contribute to understanding the organization of multigene families and telomeric sequences on bat genome as well as the chromosomal evolutionary history of Phyllostomidae bats.


Assuntos
Quirópteros/genética , DNA Ribossômico/genética , Heterocromatina , Sequências Repetitivas de Ácido Nucleico , Telômero , Animais , Centrômero , Quirópteros/classificação , Cromossomos de Mamíferos , Evolução Molecular , Hibridização in Situ Fluorescente , Família Multigênica , Filogenia
12.
Mol Biol Rep ; 41(8): 5069-75, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24771227

RESUMO

Neuroblastoma is a malignant embryonal tumor of neural crest cells that give rise to the sympathetic nervous system, responsible for 10-70% of all cases of childhood cancer. Because of its early appearance, it has been suggested that risk factors active in the prenatal can be associated with the pathogenesis of neuroblastoma. The aim of this study was to investigate whether the genetic polymorphisms MTHFR C677T and A1298C, MTR A2756G, TYMS 2R/3R and SLC19A1 G80A, involved in folate metabolism, increase the risk of neuroblastoma in Brazilian children. This study comprised 31 Brazilian children (0-14 years old) diagnosed with neuroblastoma compared with 92 controls. Investigation of polymorphisms MTHFR C677T, MTR A2756G and SLC19A1 A80G was performed using PCR-RFLP, the TYMS 2R/3R using PCR and MTHFR A1298C using AS-PCR. The SLC19A1 A80A genotype was significantly associated with the development of neuroblastoma, compared with the control group (Williams G-Test = 0.0286; OR = 5.1667; 95% CI = 1.4481-18.4338; p = 0.0175). When analyzed together, the 80AG+AA genotypes showed a trend toward association (OR = 3.3033; 95% CI = 1.0586-10.3080; p = 0.0563). Our results suggest that individuals carriers of genotype AA for the SLC19A1 gene present risk for the development of neuroblastoma and possibly have difficulty in absorption of folic acid by the cells, and this may adversely affect the metabolism of folate causing genomic instability and promoting the development of cancer. This is the first retrospective/prospective study to examine the relationship between polymorphisms of folate pathway genes and risk of neuroblastoma.


Assuntos
Proteínas de Membrana Transportadoras/genética , Neuroblastoma/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Brasil , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Ácido Fólico/metabolismo , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Proteínas de Membrana Transportadoras/metabolismo , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/metabolismo , Polimorfismo de Fragmento de Restrição , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco
13.
Reprod Fertil Dev ; 26(8): 1176-82, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25294360

RESUMO

Turner syndrome (TS) is a common genetic disorder in females associated with the absence of complete or parts of a second sex chromosome. In 5-12% of patients, mosaicism for a cell line with a normal or structurally abnormal Y chromosome is identified. The presence of Y-chromosome material is of medical importance because it results in an increased risk of developing gonadal tumours and virilisation. Molecular study and fluorescence in situ hybridisation approaches were used to study 74 Brazilian TS patients in order to determine the frequency of hidden Y-chromosome mosaicism, and to infer the potential risk of developing malignancies. Additionally, we describe one TS girl with a very uncommon karyotype 46,X,der(X)t(X;Y)(p22.3?2;q11.23) comprising a partial monosomy of Xp22.3?2 together with a partial monosomy of Yq11.23. The presence of cryptic Y-chromosome-specific sequences was detected in 2.7% of the cases. All patients with Y-chromosome-positive sequences showed normal female genitalia with no signs of virilisation. Indeed, the clinical data from Y-chromosome-positive patients was very similar to those with Y-negative results. Therefore, we recommend that the search for hidden Y-chromosome mosaicism should be carried out in all TS cases and not be limited to virilised patients or carriers of a specific karyotype.


Assuntos
Cromossomos Humanos X , Cromossomos Humanos Y , Genitália Feminina/crescimento & desenvolvimento , Mosaicismo , Translocação Genética , Síndrome de Turner/genética , Adolescente , Adulto , Brasil , Criança , Pré-Escolar , Feminino , Predisposição Genética para Doença , Testes Genéticos/métodos , Humanos , Hibridização in Situ Fluorescente , Lactente , Recém-Nascido , Cariótipo , Cariotipagem , Monossomia , Fenótipo , Reação em Cadeia da Polimerase , Valor Preditivo dos Testes , Síndrome de Turner/diagnóstico , Síndrome de Turner/fisiopatologia , Adulto Jovem
14.
Hum Immunol ; 85(6): 111164, 2024 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-39447524

RESUMO

Turner syndrome (TS) is associated with an increased susceptibility to inflammatory and autoimmune diseases. This study investigates the association between genetic polymorphisms in the IL1B and NLRP3 genes, as well as the expression profiles of IL1B, NLRP3, and NLRP1, and the risk of inflammatory and autoimmune conditions in TS patients compared to healthy controls. The genetic association analysis included 92 TS patients (case) and 146 healthy controls (HC), evaluating IL1B rs16944, NLRP3 rs10754558 and rs4925659 using TaqMan genotyping assays. In addition, mRNA expression levels of IL1B, NLRP3, and NLRP1 were also compared in 17 TS patients and 17 healthy females (control group) using qPCR-based fluorogenic probes. The study found significant associations with the G allele of rs16944 (p = 0.001) and the GG genotype (p = 0.002) in TS patients, though these were not associated with inflammatory disorders in this group., On the other hand, rs4925659 exhibited a significantly higher frequency of the A allele (p = 0.02) and AA genotype (p = 0.0001) in HC, while the A allele and GA genotype were more common in the TS group (p = 0.0001). Expression analysis revealed a downregulation of IL1B and NLRP3 (fold change: FC = -6.78 and -15.73, respectively) and an upregulation of NLRP1 (FC = 21.5) in TS patients compared to HC. These results indicate a differential distribution of IL1B and NLRP3 polymorphisms in TS patients, and suggest that alterations in the expression of IL1B, NLRP3, and NLRP1 may contribute to an inflammatory imbalance in the Turner syndrome.

15.
Artigo em Inglês | MEDLINE | ID: mdl-36759292

RESUMO

INTRODUCTION: Fanconi anemia (FA) is a rare autosomal recessive disease characterized by chromosomal instability and increased predisposition to malignancy. The diagnosis of FA requires clinical evaluation, confirmation of chromosomal fragility and/or analysis of genetic mutations. Therefore, this study aims to identify the clinical profile of patients with FA in the state of Pernambuco, Brazil. METHOD: We analyzed 100 individuals referred from the major hematology and bone marrow (BM) transplant centers in the state of Pernambuco, Brazil, between the years 2018 and 2022. The diagnosis of FA was performed using the mitomycin C chromosomal fragility test, clinical data and classical and molecular cytogenetic analyses. RESULTS: We enrolled a total of 16 patients with FA to comprise this study. Most of these individuals (87.5%) came from the Agreste and Sertão regions of Pernambuco. We observed a slight female prevalence of FA (1.3:1). The primary clinical and laboratory findings were café au lait spots (62.5%) and bone abnormalities (53%, mainly thumb deformities [40%]). We performed BM cytogenetic analysis for eight patients - seven showed no chromosomal abnormalities and one presented the karyotype 47,XY,+21 [15]. CONCLUSIONS: Our results are important to promote public health measures for the early diagnosis of FA, as well as to foster the engagement of a multidisciplinary group in the treatment of this disease.

16.
Mutat Res ; 747(1): 93-97, 2012 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-22579796

RESUMO

OBJECTIVE: To investigate whether formocresol, in Buckley's original formulation, used for pulp therapy of deciduous teeth, can have a genotoxic effect. Genotoxicity was tested in lymphocyte cultures from the peripheral blood of children aged 5-10y, in Recife, Pernambuco, Brazil. This was a case-control study. The sample comprised 40 children who had primary teeth with non-vital pulps. Two venous blood samples (6-8ml) were collected from each child, the first prior to pulp therapy (control group) and the second 24h after pulp therapy (experimental group). Lymphocyte cultures were grown in 78% RPMI 1640 medium, 20% fetal bovine serum, 2% phytohemagglutinin. The lymphocytes were assessed for chromosomal aberrations; each sample involved analysis of 100 metaphases. There was a statistically significant difference between the control and treated groups for the isochromatid gap (p<0.001), chromatid break (p<0.009), isochromatid break (p<0.046), other chromosomal alterations (p<0.001), and for total aberrations. In view of these results, caution in the use of formocresol in pediatric dentistry is recommended.


Assuntos
Capeamento da Polpa Dentária/efeitos adversos , Formocresóis/toxicidade , Mutagênicos/toxicidade , Dente Decíduo , Estudos de Casos e Controles , Criança , Pré-Escolar , Aberrações Cromossômicas , Feminino , Humanos , Masculino
17.
Mitochondrial DNA B Resour ; 7(2): 323-325, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35141410

RESUMO

The greater round-eared bat, Tonatia bidens, is a locally rare species belonging to the highly diverse family Phyllostomidae. In this study, the complete mitogenome of T. bidens was sequenced using optimized protocols of DNA extraction from fixed cells originally prepared for cytogenetic studies. Here we present the complete mitogenome and place our results in a phylogenetic context with other data generated for the family Phyllostomidae. The circular genome had 16,717 bp in size, comprising 37 genes and GC content of 42.24%. Furthermore, the phylogenetic tree indicated a well-supported relationship between the representatives of Tonatia into the subfamily Phyllostominae.

18.
Genomics ; 91(6): 544-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18378114

RESUMO

Genetic linkage studies using whole genome scans are useful approaches for identifying genes related to human diseases. In general, these studies require genotyping of a large number of markers, which are used in statistical analysis. Recent technology has allowed easy genotyping of a large number of markers in less time; therefore, interface programs are required for manipulation of these large data sets. We present a new algorithm, which processes input data in LINKAGE format from data analyzed by automated genotyping systems. The algorithm was implemented in PERL script and R environment. Validation was performed with genotyped data from 127 individuals and 720 microsatellite markers of two whole genome scans. Our results showed a significant decrease in data processing time. In addition, this algorithm provides unbiased allele frequency estimation used for linkage analysis. LINKGEN is a freely available online tool and allows easier, faster, and reliable manipulation of large genotyping data sets.


Assuntos
Algoritmos , Ligação Genética , Análise de Sequência de DNA/métodos , Software , Genoma Humano , Humanos , Repetições de Microssatélites
19.
Hematol., Transfus. Cell Ther. (Impr.) ; 46(2): 113-118, 2024. tab, graf
Artigo em Inglês | LILACS, Coleciona SUS (Brasil) | ID: biblio-1564550

RESUMO

ABSTRACT Introduction: Fanconi anemia (FA) is a rare autosomal recessive disease characterized by chromosomal instability and increased predisposition to malignancy. The diagnosis of FA requires clinical evaluation, confirmation of chromosomal fragility and/or analysis of genetic mutations. Therefore, this study aims to identify the clinical profile of patients with FA in the state of Pernambuco, Brazil. Method: We analyzed 100 individuals referred from the major hematology and bone marrow (BM) transplant centers in the state of Pernambuco, Brazil, between the years 2018 and 2022. The diagnosis of FA was performed using the mitomycin C chromosomal fragility test, clinical data and classical and molecular cytogenetic analyses. Results: We enrolled a total of 16 patients with FA to comprise this study. Most of these individuals (87.5%) came from the Agreste and Sertão regions of Pernambuco. We observed a slight female prevalence of FA (1.3:1). The primary clinical and laboratory findings were café au lait spots (62.5%) and bone abnormalities (53%, mainly thumb deformities [40%]). We performed BM cytogenetic analysis for eight patients - seven showed no chromosomal abnormalities and one presented the karyotype 47,XY,+21 [15]. Conclusions: Our results are important to promote public health measures for the early diagnosis of FA, as well as to foster the engagement of a multidisciplinary group in the treatment of this disease.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Citogenética , Anemia de Fanconi
20.
Int J Radiat Biol ; 95(8): 1058-1071, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31008687

RESUMO

Purpose: The goal was to compare the micronucleus (MN) and dicentric plus ring chromosomes (D + R) assays for dose assessment in cases of partial body irradiations (PBI). Materials and methods: We constructed calibration curves for each assay at doses ranging from 0 to 5 Gy of X-rays at dose rate of 0.275 Gy/min. To simulate partial-body exposures, blood samples from two donors were irradiated with 0.5, 1, 2 and 4 Gy and the ratios of irradiated to unirradiated blood were 25, 50, and 100%. Different tests were used to confirm if all samples were overdispersed or zero-inflated and for partial-body dose assessment we used the Qdr, Dolphin and Bayesian model. Results: In our samples for D + R calibration curve, practically all doses agreed with Poisson assumption, but MN exhibited overdispersed and zero-inflated cellular distributions. The exact Poisson tests and zero-inflated tests demonstrate that virtually all samples of D + R from PBI simulation fit the Poisson distribution and were not zero-inflated, but the MN samples were also overdispersed and zero-inflated. In the partial-body estimation, when Qdr and Dolphin methods were used the D + R results were better than MN, but the doses estimation defined by the Bayesian methodology were more accurate than the classical methods. Conclusions: Dicentric chromosomes continue to prove to be the best biological marker for dose assessment. However exposure scenarios of partial-body estimation, overdispersion and zero-inflation may not occur, it being a critical point not only for dose assessment, but also to confirm partial-body exposure. MN could be used as alternative assay for partial-body dose estimation, but in case of an accident without any information, the MN assay could not define whether the accident was a whole-body irradiation (WBI) or a PBI.


Assuntos
Testes para Micronúcleos , Doses de Radiação , Cromossomos em Anel , Aberrações Cromossômicas , Relação Dose-Resposta à Radiação , Humanos , Distribuição de Poisson
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