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1.
J Appl Stat ; 51(2): 324-347, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38351977

RESUMO

Synthetic aperture radar (SAR) provides an efficient way to monitor the Earth's surface. But the speckle noise that the SAR system generates when acquiring images makes it difficult to understand and interpret SAR intensity features. To automatically analyze SAR images, this paper presents a K-Bessel regression (KBR) model in which a function of the mean intensity response is explained by other features (or covariates) determined in parallel. Some mathematical properties of this regression are derived and discussed in the context of the physical origin of the SAR image. A maximum likelihood estimation procedure is planned and its performance is quantified by Monte Carlo experiments. An application to real data obtained from a polarimetric SAR image of San Francisco Bay is realized. Results show that both the KBR-based processing is more informative than the unconditional approach to describe SAR intensity and that our proposal can outperform the normal and gamma regression models. Finally, it is shown that the KBR model is useful to reproduce the relief signal of one channel from the intensity values of the other.

2.
Sci Adv ; 6(2): eaaw6284, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31950075

RESUMO

Zika virus (ZIKV) infection during pregnancy is associated with a spectrum of developmental impairments known as congenital Zika syndrome (CZS). The prevalence of this syndrome varies across ZIKV endemic regions, suggesting that its occurrence could depend on cofactors. Here, we evaluate the relevance of protein malnutrition for the emergence of CZS. Epidemiological data from the ZIKV outbreak in the Americas suggest a relationship between undernutrition and cases of microcephaly. To experimentally examine this relationship, we use immunocompetent pregnant mice, which were subjected to protein malnutrition and infected with a Brazilian ZIKV strain. We found that the combination of protein restriction and ZIKV infection leads to severe alterations of placental structure and embryonic body growth, with offspring displaying a reduction in neurogenesis and postnatal brain size. RNA-seq analysis reveals gene expression deregulation required for brain development in infected low-protein progeny. These results suggest that maternal protein malnutrition increases susceptibility to CZS.


Assuntos
Desnutrição/complicações , Infecção por Zika virus/congênito , Infecção por Zika virus/complicações , Animais , Animais Recém-Nascidos , Peso Corporal , Encéfalo/enzimologia , Encéfalo/patologia , Brasil/epidemiologia , Dieta com Restrição de Proteínas , Surtos de Doenças , Embrião de Mamíferos/patologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Desnutrição/virologia , Camundongos Endogâmicos C57BL , Microcefalia/complicações , Microcefalia/virologia , Neurogênese , Tamanho do Órgão , Gravidez , Síndrome , Carga Viral , Infecção por Zika virus/virologia
3.
Med Vet Entomol ; 33(3): 397-406, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30887540

RESUMO

New species of insect-specific viruses (ISV) have been reported worldwide. In the present study, the complete genome of Culex flavivirus (CxFV) and partial sequences of other ISVs in Culex quinquefasciatus Say 1823 females (n = 3425) sampled in 200 urban areas census tracts of Cuiaba, state of Mato Grosso, were identified via reverse transcriptase-polymerase chain reaction for a NS5 region of flaviviruses, nucleotide and high-throughput sequencing, and viral isolation in C6/36 cells. CxFV was detected in 16 of 403 mosquito pools; sequences found in the study presented a high similarity with isolates from São Paulo, Brazil and other countries in Latin American that belong to genotype II, supporting the geographical influence on CxFV evolution. The monthly maximum likelihood estimation for CxFV ranged from 1.81 to 9.94 per 1000 mosquitoes. In addition to the CxFV complete genome, one pool contained an ORF1 sequence (756 bp) that belongs to a novel Negevirus from the Sandewavirus supergroup most similar to the Santana virus (77.1%) and another pool presented an RNA-dependent RNA polymerase sequence (1081 bp) of a novel Rhabdovirus most similar to Wuhan mosquito virus 9 (44%). After three passages in C6/36 cells, only CxFV was isolated from these co-infected pools. The importance of ISVs relies on their possible ability to interfere with arbovirus replication in competent vectors.


Assuntos
Culex/virologia , Flavivirus/genética , Genoma Viral , Animais , Brasil , Feminino , Flavivirus/classificação , Flavivirus/isolamento & purificação , Genótipo , Filogenia
4.
Lupus ; 20(3): 265-73, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21233146

RESUMO

Systemic lupus erythematosus (SLE) is an autoimmune disorder of the connective tissue with a wide and heterogeneous spectrum of manifestations, with renal and neurological involvement usually related to worse prognosis. SLE more frequently affects females of reproductive age, and a high prevalence and renal manifestation seem to be associated with non-European ethnicity. The present study aims to investigate candidate loci to SLE predisposition and evaluate the influence of ethnic ancestry in the disease risk and clinical phenotypic heterogeneity of lupus at onset. Samples represented by 111 patients and 345 controls, originated from the city of Belém, located in the Northern Region of Brazil, were investigated for polymorphisms in HLA-G, HLA-C, SLC11A1, MTHFR, CASP8 and 15 KIR genes, in addition to 89 Amerindian samples genotyped for SLC11A1. We also investigated 48 insertion/deletion ancestry markers to characterize individual African, European and Amerindian ancestry proportions in the samples. Predisposition to SLE was associated with GTGT deletion at the SLC11A1 3'UTR, presence of KIR2DS2 +/KIR2DS5 +/KIR3DS1 + profile, increased number of stimulatory KIR genes, and European and Amerindian ancestries. The ancestry analysis ruled out ethnic differences between controls and patients as the source of the observed associations. Moreover, the African ancestry was associated with renal manifestations.


Assuntos
Proteínas de Transporte de Cátions/genética , Etnicidade/genética , Marcadores Genéticos , Predisposição Genética para Doença , Lúpus Eritematoso Sistêmico/genética , Polimorfismo Genético , Receptores KIR/genética , Adulto , Idade de Início , Brasil , Cidades , Feminino , Frequência do Gene , Humanos , Lúpus Eritematoso Sistêmico/etnologia , Masculino , Receptores KIR3DS1/genética
5.
Rev. bras. plantas med ; 13(4): 507-511, 2011. tab
Artigo em Inglês | LILACS | ID: lil-611456

RESUMO

"Quina" (Strychnos pseudoquina A. St. Hil) is a medicinal plant species from the Brazilian Cerrado. As its seeds show dormancy, they were subjected to the treatments pre-cooling at 5ºC during 7 days, pre-heating at 40ºC during 7 days, pre-soaking in sulfuric acid PA during 5 and 15 min, pre-soaking in boiling water during 5 and 15 min, pre-soaking in 100 and 200 ppm gibberellic acid during 48 h, pre-soaking in distilled water during 24 and 48 h, and mechanical scarification to break dormancy. Counts were daily conducted from the 2nd day after the experiment implementation until the germination stabilization at the 65th day. The germination speed index (GSI) and the germination percentage were evaluated. Germination rates above 96 percent were reached in seeds pre-soaked in water during 48 h and substrate moistened with water or KNO3.


A quina (Strychnos pseudoquina A. St.-Hil) é espécie medicinal do Cerrado Brasileiro. As sementes apresentam dormência e, por isso, foram submetidas aos tratamentos pré-resfriamento a 5ºC durante 7 dias, pré-aquecimento a 40ºC durante 7 dias, pré-embebição em ácido sulfúrico P.A. durante 5 e 15 minutos, pré-embebição em água fervente durante 5 e 15 minutos, pré-embebição em ácido giberélico a 100 e 200 ppm, durante 48 horas, pré-embebição em água destilada durante 24 e 48 horas e escarificação mecânica, visando à superação da dormência. Foram realizadas contagens diárias entre o 2º dia após a implantação do experimento até a estabilização da germinação, que ocorreu no 65º dia. Foram avaliados o índice de velocidade de germinação (IVG) e a porcentagem de germinação. Taxas de germinação acima de 96 por cento foram atingidas em sementes pré-embebidas em água durante 48 horas e substrato umedecido com água ou KNO3.


Assuntos
Germinação , Sementes/crescimento & desenvolvimento , Strychnos/embriologia , Loganiaceae/crescimento & desenvolvimento , Loganiaceae/efeitos adversos , Loganiaceae/embriologia , Plantas Medicinais
6.
Rev Bras Enferm ; 52(4): 529-38, 1999.
Artigo em Português | MEDLINE | ID: mdl-12143810

RESUMO

The physical exam is constituted inside in an important stage of the evaluation process to the child, through which the nurse enriches the information obtained during the interview and it bases the nursing care. At the present time, by means of the nurses growing interest in applying the nursing process in whole its stages, the physical exam has been occupying prominence place, for allowing the nurses to know the its customers' needs, in what says respect to its physical and physiologic aspects, allowing the identification of the nursing diagnoses, besides serving as resource for evaluation effective of the nursing interventions. This study, of bibliographical character, objectified to elaborate a guide for accomplishment of the physical exam in the child, to be used by nurses, during the evaluation process to the child. In him we presented the physical exam in a systematic way, using the sequence cephalic-flow, presenting the possible normal and abnormal discoveries to the we examine the child.


Assuntos
Enfermagem Pediátrica/métodos , Exame Físico/métodos , Exame Físico/enfermagem , Criança , Humanos
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