RESUMO
Infections by pathogenic New World mammarenaviruses (NWM)s, including Junín virus (JUNV), can result in a severe life-threatening viral hemorrhagic fever syndrome. In the absence of FDA-licensed vaccines or antivirals, these viruses are considered high priority pathogens. The mammarenavirus envelope glycoprotein complex (GPC) mediates pH-dependent fusion between viral and cellular membranes, which is essential to viral entry and may be vulnerable to small-molecule inhibitors that disrupt this process. ARN-75039 is a potent fusion inhibitor of a broad spectrum of pseudotyped and native mammarenaviruses in cell culture and Tacaribe virus infection in mice. In the present study, we evaluated ARN-75039 against pathogenic JUNV in the rigorous guinea pig infection model. The compound was well-tolerated and had favorable pharmacokinetics supporting once-per-day oral dosing in guinea pigs. Importantly, significant protection against JUNV challenge was observed even when ARN-75039 was withheld until 6 days after the viral challenge when clinical signs of disease are starting to develop. We also show that ARN-75039 combination treatment with favipiravir, a viral polymerase inhibitor, results in synergistic activity in vitro and improves survival outcomes in JUNV-challenged guinea pigs. Our findings support the continued development of ARN-75039 as an attractive therapeutic candidate for treating mammarenaviral hemorrhagic fevers, including those associated with NWM infection.
Assuntos
Arenaviridae , Febre Hemorrágica Americana , Febres Hemorrágicas Virais , Vírus Junin , Cobaias , Camundongos , Animais , Febre Hemorrágica Americana/tratamento farmacológico , Pirazinas/farmacologia , Pirazinas/uso terapêutico , Amidas/farmacologia , Amidas/uso terapêutico , Antirretrovirais/farmacologiaRESUMO
Several arenaviruses, including Lassa and Lujo viruses in Africa and five New World arenavirus (NWA) species in the Americas, cause life-threatening viral hemorrhagic fevers. In the absence of licensed antiviral therapies, these viruses pose a significant public health risk. The envelope glycoprotein complex (GPC) mediates arenavirus entry through a pH-dependent fusion of the viral and host endosomal membranes. It thus is recognized as a viable target for small-molecule fusion inhibitors. Here, we report on the antiviral activity and pre-clinical development of the novel broad-spectrum arenavirus fusion inhibitors, ARN-75039 and ARN-75041. In Tacaribe virus (TCRV) pseudotyped and native virus assays, the ARN compounds were active in the low to sub-nanomolar range with selectivity indices exceeding 1000. Pharmacokinetic analysis of the orally administered compounds revealed an extended half-life in mice supporting once-daily dosing, and the compounds were well tolerated at the highest tested dose of 100 mg/kg. In a proof-of-concept prophylactic efficacy study, doses of 10 and 35 mg/kg of either compound dramatically improved survival outcome and potently inhibited TCRV replication in serum and various tissues. Additionally, in contrast to surviving mice that received ribavirin or placebo, animals treated with ARN-75039 or ARN-75041 were cured of TCRV infection. In a follow-up study with ARN-75039, impressive therapeutic efficacy was demonstrated under conditions where treatment was withheld until after the onset of disease. Taken together, the data strongly support the continued development of ARN-75039 as a candidate therapeutic for the treatment of severe arenaviral diseases.
Assuntos
Antivirais/farmacologia , Infecções por Arenaviridae/tratamento farmacológico , Arenavirus do Novo Mundo/efeitos dos fármacos , Fusão de Membrana/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/farmacologia , Administração Oral , Animais , Antivirais/farmacocinética , Chlorocebus aethiops , Masculino , Camundongos , Ribavirina/farmacologia , Bibliotecas de Moléculas Pequenas/farmacocinética , Células Vero , Proteínas do Envelope Viral/química , Proteínas do Envelope Viral/metabolismo , Internalização do Vírus/efeitos dos fármacosRESUMO
PURPOSE: To evaluate the role of SWE in characterizing breast masses and ascertain whether additional use of SWE to ultrasound for evaluating BI-RADS 3 and 4a masses could help reduce long-term follow-up and unnecessary biopsies of these suspicious breast masses. MATERIALS AND METHODS: This prospective, cross-sectional study was performed between June 2013 and November 2014. All enrolled patients underwent clinical breast examination, ultrasound, SWE and ultrasound-guided core biopsy of the breast mass. Breast Imaging Reporting and Data System (BI-RAD) categories were assigned to breast masses. For qualitative and quantitative variables of SWE, cut-off values for differentiation between benign and malignant breast masses were estimated. Modified BIRADS' (up/downgrading of BIRADS category) was done for BI-RADS 3/4a masses by combining individual SWE parameters and ultrasound findings. Sensitivity, specificity, positive and negative predictive value of modified BI-RADS' and ultrasound BI-RADS were compared. RESULTS: A total of 119 women (mean age, 42.3±13.6 [SD] years; range: 13-87 years) with a single breast mass each were enrolled. Histopathologically, 57/119 (48%) breast masses were benign and 62 (52%) were malignant. On ultrasound, 42 breast masses were BI-RADS3 and 77 were BI-RADS 4 (4a, n=10; 4b, n=24; 4c, n=43) leading to 96.8% sensitivity and 70.2% specificity. On SWE, benign breast masses were oval/round, homogenous/reasonably homogenous, blue/green with lower elasticity values and malignant breast masses were irregular, inhomogeneous, red/orange with high elasticity values. On modified BI-RADS' using E-color and E-mean/E-max, specificity improved to 78.9% and 75.4% respectively. CONCLUSION: Addition of SWE to ultrasound improves characterization of BI-RADS 3 and 4a masses. E-max, E-mean and E-color are the most useful SWE parameters to differentiate between malignant and benign breast masses.
Assuntos
Doenças Mamárias/diagnóstico por imagem , Técnicas de Imagem por Elasticidade , Ultrassonografia Mamária , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto JovemRESUMO
As one of the world's most important food crops, the potato (Solanum tuberosum L.) has spurred innovation in autotetraploid genetics, including in the use of SNP arrays to determine allele dosage at thousands of markers. By combining genotype and pedigree information with phenotype data for economically important traits, the objectives of this study were to (1) partition the genetic variance into additive vs. nonadditive components, and (2) determine the accuracy of genome-wide prediction. Between 2012 and 2017, a training population of 571 clones was evaluated for total yield, specific gravity, and chip fry color. Genomic covariance matrices for additive (G), digenic dominant (D), and additive × additive epistatic (G#G) effects were calculated using 3895 markers, and the numerator relationship matrix (A) was calculated from a 13-generation pedigree. Based on model fit and prediction accuracy, mixed model analysis with G was superior to A for yield and fry color but not specific gravity. The amount of additive genetic variance captured by markers was 20% of the total genetic variance for specific gravity, compared to 45% for yield and fry color. Within the training population, including nonadditive effects improved accuracy and/or bias for all three traits when predicting total genotypic value. When six F1 populations were used for validation, prediction accuracy ranged from 0.06 to 0.63 and was consistently lower (0.13 on average) without allele dosage information. We conclude that genome-wide prediction is feasible in potato and that it will improve selection for breeding value given the substantial amount of nonadditive genetic variance in elite germplasm.
Assuntos
Alelos , Dosagem de Genes , Variação Genética , Genoma de Planta , Estudo de Associação Genômica Ampla , Poliploidia , Solanum tuberosum/genética , Algoritmos , Modelos Genéticos , Linhagem , Reprodutibilidade dos Testes , Seleção GenéticaRESUMO
European hazelnut (Corylus avellana L.) is the only economically important nut crop in the family Betulaceae. Because of its small genome size (~385 Mb / 1C), relatively short life cycle, availability of a dense linkage map, and amenability to transformation by Agrobacterium, the European hazelnut could serve as a model plant for the Betulaceae. Here we report the construction of a bacterial artificial chromosome (BAC) library for 'Jefferson' hazelnut using the cloning enzyme MboI and the vector pECBAC1 (BamHI site). The library consists of 39,936 clones arrayed in 104,384-well microtitre plates with a mean insert size of 117 kb. The genomic coverage of the library is estimated to be about 12 genome equivalents. This library provides a valuable resource for the map-based cloning of two important genes, the resistance gene from 'Gasaway' that confers resistance to eastern filbert blight caused by the fungus Anisogramma anomala (Peck) E. Müller and the S locus that controls pollen-stigma incompatibility. Fine-resolution mapping near the two loci was carried out using random amplified polymorphic DNA (RAPD) and simple sequence repeat (SSR) markers. Fine mapping at the disease resistance locus showed that markers W07-375 and X01-825 flanked the resistance locus at distances of 0.06 and 0.05 cM, respectively. The S locus is flanked by markers 204-950 and KG819-200 at distances of 0.14 and 0.24 cM, respectively. Assuming that 1 cM corresponds to a physical distance of 430 kb, it will take approximately two to three chromosome walks to assemble BAC contigs that span both loci.
Assuntos
Agrobacterium/genética , Ascomicetos/fisiologia , Cromossomos Artificiais Bacterianos , Corylus/genética , Biblioteca Gênica , Doenças das Plantas/genética , Corylus/microbiologia , Resistência à Doença , Marcadores Genéticos , Genoma de Planta , Repetições de Microssatélites , Fenótipo , Doenças das Plantas/microbiologiaRESUMO
Heparan sulphate (HS) is a linear glycosaminoglycan found ubiquitously on the surface and in the pericellular matrix of metazoan cells that is covalently attached to core proteins to form HS proteoglycans. HS interacts specifically with a large number (> 100) of extracellular regulatory proteins, many of which are key players in mammary development and function. HS thus acts a receptor, in which capacity it regulates the bioavailability, localisation and activity of these regulatory proteins.
Assuntos
Mama/metabolismo , Substâncias de Crescimento/metabolismo , Heparitina Sulfato/metabolismo , Glândulas Mamárias Animais/metabolismo , Animais , Feminino , Humanos , Receptores de Superfície Celular/metabolismo , Transdução de SinaisRESUMO
The clinical response to various therapeutic agents was evaluated in 31 patients with phrynoderma. A complete clinical response with vitamin B-complex was noted in an average period of 5.7 weeks. In patients treated with vitamin E, partial or total improvement was seen in an average period of 12.3 and 10.7 weeks respectively. Patients treated with safflower oil showed a partial improvement in an average period of 13.2 weeks. The essential fatty acid (EFA) nutriture of 30 patients was compared with 7 controls. Plasma phospholipid fatty acid composition was used as an indicator of EFA nutriture. The patients with phrynoderma fell into two groups. In the 23 children in one group (pattern A), the mean levels of linoleic (18:2 omega 6), arachidonic (20:4 omega 6) and eicosatrienoic (20:3 omega 9) acids were similar to the levels in the controls. The ratio of eicosatrienoic to arachidonic acids (20:3 omega 9/20:4 omega 6), which is considered an accurate measure of EFA nutritional status, was 0.12 and in the normal range, suggesting that the EFA nutriture is normal in phrynoderma. The ratio of linoleic to arachidonic acids (18:2 omega 6/20:4 omega 6) was also found to be normal, suggesting that the metabolism of linoleic to arachidonic acid is not affected in phrynoderma. In seven children in a second group (pattern B), the fatty acid profile was different from patients with pattern A. In these two groups no obvious differences were noted in clinical features and severity. In patients treated with safflower oil, the mean levels of vitamin E were elevated. On all the three treatment schedules, the levels of other fatty acids were not altered. The biochemical and clinical evidence obtained indicate that phrynoderma may not be directly associated with EFA deficiency but that vitamin B-complex may have an important role. The plasma phospholipid fatty acid profile seems to reflect neither the clinical situation nor the response to therapy.