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1.
Sci Total Environ ; 769: 144988, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33486180

RESUMO

Wildfire is a natural process in Brazilian savannas, but human activities alter fire regimes and threaten biodiversity. In this study, we used an ecoacoustics approach to assess fauna responses and recovery after wildfire in a Brazilian savanna. Six passive acoustic monitoring devices were used to record soundscapes before and after a wildfire a at burned and non-burned sites for one year and one month (September 2012 to September 2013). Power Spectral Density and the Acoustic Complexity Index were used to track biophony. Before the fire, the two sites had similar biophonic patterns (PSD: T = 1136, Z = 1.52, P = 0.12; ACI: T = 1117, Z = 1.10, P = 0.26) and soniferous species richness (Site 1 = 52 and Site 2 = 49). However, in the first two sessions of recordings after the fire, biophony became higher at the burned site during the day (PSD: T = 211 and 233; Z = 4.13 and 6.41; ACI: T = 120 and 469, Z = 5.14 and 7.07; all P < 0.00). During the night, biophony was usually higher at the non-burned site until May 2013 (PSD: T = 0 to 453; Z = 3.30 to 5.90; ACI: T = 333 to 491, Z = 3.80 to 4.93; all P < 0.00). Biophony became similar (P = 0.17 to 0.38) at the two sites or higher (P = 0.00 to 0.01) at the burned site from July to September 2013 (PSD: T = 55 to 1167; Z = 1.35 to 6.89; ACI: T = 719 to 1365, Z = 0.87 to 3.04). After the fire, a reduction of soniferous species at the burned site was observed for insects and bats. Both biophonic activity and soniferous species showed a tendency to recover one year after the fire, but there were still less species in September 2013 (non-burned = 43 and burned = 37) when compared to September 2012 at both sites (Site 1 = 52 and Site 2 = 49). Our results showed that changes in the natural regimes of fire can negatively impact the biodiversity and reinforce the need for monitoring protocols and inspection of wildfires.


Assuntos
Incêndios , Incêndios Florestais , Biodiversidade , Brasil , Ecossistema , Pradaria , Humanos
2.
Primates ; 59(1): 89-97, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28894994

RESUMO

Anthropogenic noise pollution is increasing and can constrain acoustic communication in animals. Our aim was to investigate if the acoustic parameters of loud calls and their diurnal pattern in the black-fronted titi monkey (Callicebus nigrifrons) are affected by noise produced by mining activity in a fragment of Atlantic Forest in Brazil. We installed two passive acoustic monitoring devices to record sound 24 h/day, 7 days every 2 months, for a year; one unit was close to an opencast mine and the other 2.5 km away from it. Both sites presented similar habitat structures and were inhabited by groups of black-fronted titi monkeys. We quantified the noise at both sites by measuring the equivalent continuous sound level every 2 months for 1 year and quantified the emission of loud calls by titi monkeys through visual inspection of the recordings. The close site presented higher ambient noise levels than the far site. The quantitative comparison of loud calls of black-fronted titi monkeys between the two sites showed less calling activity in the site close to the mine than in the site further away. Approximately 20 % of the calls detected at the site close to the mine were masked by noise from truck traffic. Loud calls were longer at the site far from the mine and the diurnal patterns of vocal activity differed in the amount of calling as well as in the timing of peak calling activity between the two sites. Our results indicate that mining noise may constrain titi monkeys' long-distance vocal communication. Loud calls occupy a similar frequency band to mining noise, and an increase in ambient noise may be triggering black-fronted titi monkeys to adjust their long-distance communication patterns to avoid masking of their calls. Given that vocalizations are an important means of social interaction in this species, there are concerns about the impact of mining noise on populations exposed to this human activity.


Assuntos
Mineração , Ruído , Pitheciidae/fisiologia , Vocalização Animal , Animais , Brasil
3.
Int Endod J ; 50(12): 1192-1200, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28196285

RESUMO

AIM: To evaluate the internal and external morphologies of fused-rooted maxillary second molars by means of micro-computed tomography (micro-CT) analysis. METHODOLOGY: A total of 100 fused-rooted maxillary second molars from a Brazilian subpopulation were divided into six groups according to the root morphology. The samples were scanned at a resolution of 19.6 µm and evaluated with regard to the external morphology of the roots, the root canal configuration, the percentage frequency of C-shaped canals and isthmuses, as well as the morphology of the root canal system at 1, 2 and 3 mm from the anatomical apex of the fused roots. RESULTS: The most prevalent root canal fusions were type 1, mesiobuccal root fused with distobuccal root (32%), followed by type 3, DB root fused with P root (27%), and type 4, MB root fused with DB root, and P root fused with MB or DB roots (21%). The prevalence of C-shaped root canal systems were 22%. Depending on the type of root fusion, the percentage frequency of isthmuses in the apical level varied from 9.3% to 42.8%, whilst the presence of apical deltas ranged from 18.5% to 57.1% of teeth. CONCLUSIONS: The root canal system of maxillary second molars with fused roots may have a high incidence of merging canals, isthmuses, apical deltas and C-shaped configurations.


Assuntos
Dente Molar/anormalidades , Raiz Dentária/anormalidades , Humanos , Imageamento Tridimensional , Maxila , Dente Molar/anatomia & histologia , Dente Molar/diagnóstico por imagem , Raiz Dentária/anatomia & histologia , Raiz Dentária/diagnóstico por imagem , Microtomografia por Raio-X
4.
SAR QSAR Environ Res ; 26(3): 205-16, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25774798

RESUMO

Theoretical models for exploring the antischistosomal activity of a dataset of 18 synthetic neolignans are built using the multivariate image analysis applied to structure-activity relationships (MIA-SAR) approach. The obtained models were validated using the accuracy (Acc) in leave-one-out cross-validation, external validation and Y-randomization procedures, yielding correct classification superior to 80%, 70% and 60%, respectively. Additionally, a comparison was made of the models obtained from binary (black and white) and coloured images; the colours (pixel values) were selected to correspond to chemical properties. It was observed that the models obtained from coloured images with pixel values corresponding to electronegativity (known as the aug-MIA-SAR(colour) approach) generally yielded superior statistical parameters compared with those obtained from binary images (MIA-SAR) and randomly coloured images (atoms are coloured according to their type) with atomic sizes corresponding to Van der Waals radius (aug-MIA-SAR), respectively. Mechanistic interpretation of the influence of different substituents on the antischistosomal activity revealed that methoxy substituents in the R1 (or R2) and R5 positions of the neolignan scaffold are indispensable for the antischistosomal activity. The obtained results provide knowledge of the possible structural modifications to yield novel neolignan compounds with antischistosomal activity.


Assuntos
Simulação por Computador , Lignanas/farmacologia , Relação Quantitativa Estrutura-Atividade , Ratos , Doenças dos Roedores/tratamento farmacológico , Schistosoma mansoni/efeitos dos fármacos , Esquistossomose mansoni/veterinária , Esquistossomicidas/farmacologia , Animais , Lignanas/química , Modelos Biológicos , Análise Multivariada , Doenças dos Roedores/parasitologia , Esquistossomose mansoni/tratamento farmacológico , Esquistossomose mansoni/parasitologia , Esquistossomicidas/química
5.
J Pediatr Hematol Oncol ; 19(6): 516-22, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9407937

RESUMO

PURPOSE: B cell precursors acute lymphoblastic leukemia (ALL) present rearrangements in the heavy chain immunoglobulin and T cell receptor genes, especially in the complementarity determining region 3 (CDR-3) and T cell receptor delta (TCR delta) (V delta 2 D delta 3) regions. These rearrangements may be amplified by the polymerase chain reaction (PCR) and used as clonal markers of B lineage ALL. Our purpose was to study clonality at the DNA level by PCR in B lineage ALL. PATIENTS AND METHODS: Fifty-three pediatric patients (36 with B lineage ALL, 7 with ALL-T, and 10 with nonlymphocytic disease) were investigated using consensus primers for the CDR-3 regions of IgH and TCR delta. RESULTS: Clonality was detected in 86.1% of the patients with B lineage ALL when the primers for the CDR-3 regions were used, in 41.6% when the primers for TCR delta were used, and in 91.6% when the two primers were used together. Biclonality was found in 22.5% and 6.6% of patients that have shown clonality for CDR-3 and TCR delta, respectively. Clonality was not detected in any other samples using these primers. CONCLUSIONS: PCR using CDR-3 and TCR delta primers can be used as an aid for B lineage ALL diagnosis and clonal evolution of theses disease.


Assuntos
Linfoma de Burkitt/genética , Linfoma de Burkitt/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Criança , Pré-Escolar , Células Clonais , Sequência Consenso , Primers do DNA , DNA de Neoplasias/análise , DNA de Neoplasias/genética , Feminino , Amplificação de Genes , Rearranjo Gênico de Cadeia Pesada de Linfócito B , Rearranjo Gênico da Cadeia delta dos Receptores de Antígenos dos Linfócitos T , Humanos , Cadeias Pesadas de Imunoglobulinas/genética , Região Variável de Imunoglobulina/genética , Lactente , Masculino , Reação em Cadeia da Polimerase , Receptores de Antígenos de Linfócitos T gama-delta/genética
6.
Hum Genet ; 97(5): 596-8, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8655137

RESUMO

Two 46,XX true hermaphrodites and one XX male without genital ambiguities are reported. They coexist in two generations of the same pedigree, with paternal transmission and in the absence of SRY (sex-determining region, Y chromosome). These familial cases provide evidence to support the hypothesis that these disorders are alternative manifestations of the same genetic defect, probably an autosomal dominant mutation (with incomplete penetrance) or an X-linked mutation (limited by the presence of the Y chromosome).


Assuntos
Proteínas de Ligação a DNA/genética , Transtornos do Desenvolvimento Sexual/genética , Proteínas Nucleares , Fatores de Transcrição , Cromossomo X , Adulto , Sequência de Bases , Criança , Primers do DNA , Feminino , Genes Dominantes , Genitália Feminina/patologia , Genitália Feminina/cirurgia , Genitália Masculina/patologia , Humanos , Recém-Nascido , Cariotipagem , Masculino , Dados de Sequência Molecular , Mutação , Linhagem , Reação em Cadeia da Polimerase , Análise para Determinação do Sexo , Proteína da Região Y Determinante do Sexo , Cromossomo Y
7.
Cancer Genet Cytogenet ; 86(1): 83-5, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8616796

RESUMO

The authors studied cytogenetically a case of CD30+ anaplastic large cell non-Hodgkin lymphoma previously diagnosed as malignant histiocytosis and detected a translocation involving chromosomes 1 and 5, t(1;5)(q32:q35). After comparing their findings with those from reports in the literature, they comment about the importance of breakpoint q35 on chromosome 5 and point out the importance of associating morphologic, immunoperoxidase, and cytogenetic findings to confirm the diagnosis of this tumor.


Assuntos
Cromossomos Humanos Par 1 , Cromossomos Humanos Par 5 , Linfoma Anaplásico de Células Grandes/genética , Translocação Genética , Fragilidade Cromossômica , Humanos , Lactente , Cariotipagem , Masculino
8.
J. pediatr. (Rio J.) ; 67(7/8): 267-9, jul.-ago. 1991. tab, ilus
Artigo em Português | LILACS | ID: lil-119093

RESUMO

Os autores analisam citogeneticamente celulas derivadas de um tumor de Wilms objetivando estabelecer correlacao entre poliploidia e histologia desfavoravel. O exame citogenetico do caso foi realizado por metodo diretocom analise de 20 metafases, que revelou poliploidia em 100% das celulas analisadas, com variacao de 60 a 69 cromossomos. O resultado histologico foi do tipo blastemal anaplasico. Os dados sao consistentes com outros da literatura realizados tanto com exame citogenetico como atraves de analise de DNA por citometria de fluxo, que associam poliploidia com histologia desfavoravel e confirmam o exame citogenetico como um elemento importante na avaliacao do prognostico desta neoplasia .


Assuntos
Criança , Humanos , Masculino , Citogenética , Neoplasias Renais , Poliploidia , Tumor de Wilms/patologia
9.
Cancer Genet Cytogenet ; 49(1): 25-30, 1990 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-2397470

RESUMO

We report a case of childhood erythroleukemia diagnosed by French-American-British Cooperative group (FAB) and by cytogenetic analysis of bone marrow cells. The following major chromosome anomalies were detected: hyperdiploidy with a modal number of 49, three markers consisting of translocations between chromosomes 3, 9, 20, and 15, deletion of the long arm of chromosome 16 (q22----qter), and karyotype instability. These changes were compared with others reported in the literature and discussed in terms of their importance for diagnostic confirmation.


Assuntos
Aberrações Cromossômicas , Leucemia Eritroblástica Aguda/genética , Medula Óssea/ultraestrutura , Pré-Escolar , Bandeamento Cromossômico , Marcadores Genéticos , Humanos , Cariotipagem , Masculino
10.
Ann Genet ; 33(1): 56-9, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2195984

RESUMO

Two half-sisters with distal monosomy of the long arm of chromosome 6 (q25----qter) inherited by maternal translocation t(6q;17q) were investigated. The clinical manifestations of these patients are compared with eight cases reported in the literature for further characterization of the 6q-syndrome. The cytogenetic diagnosis of alterations involving small chromosome fragments and the different origins of this type of deletion are also discussed.


Assuntos
Anormalidades Múltiplas/genética , Aberrações Cromossômicas/genética , Deleção Cromossômica , Cromossomos Humanos Par 17/ultraestrutura , Cromossomos Humanos Par 6/ultraestrutura , Monossomia , Translocação Genética , Transtornos Cromossômicos , Face/anormalidades , Feminino , Humanos , Recém-Nascido , Deficiência Intelectual/genética , Convulsões/genética
11.
Arq Neuropsiquiatr ; 47(2): 205-11, 1989 Jun.
Artigo em Português | MEDLINE | ID: mdl-2597013

RESUMO

A patient with ring 14 chromosome is reported. On the basis of this case and of a review of 28 cases published in the literature, the frequency of clinical signs and symptoms is determined, the constant and early incidence of epileptic seizures is emphasized and their characteristics are described. The associated congenital malformations are listed and their importance for karyotyping and consequent detection of new cases is emphasized.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos Par 14 , Epilepsia/genética , Cromossomos em Anel , Anormalidades Múltiplas , Pré-Escolar , Bandeamento Cromossômico , Dermatoglifia , Humanos , Masculino
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