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41.
Igor Koloniuk Alena Matyov Sra Brzdov Jana Vesel Jaroslava Pibylov Jana Frnov Santiago F. Elena 《Viruses》2022,14(7)
Advances in high-throughput sequencing methods have boosted the discovery of multistrain viral infections in diverse plant systems. This phenomenon appears to be pervasive for certain viral species. However, our knowledge of the transmission aspects leading to the establishment of such mixed infections is limited. Recently, we reported a mixed infection of a single strawberry plant with strawberry mottle virus (SMoV), strawberry crinkle virus (SCV) and strawberry virus 1 (StrV-1). While SCV and StrV-1 are represented by two and three molecular variants, respectively, SmoV has three different RNA1 and RNA2 segments. In this study, we focus on virus acquisition by individual adult aphids of the Aphis gossypii, Aphis forbesi and Chaetosiphon fragaefolii species. Single-aphid transmission trials are performed under experimental conditions. Both different viruses and individual virus strains show varying performances in single aphid acquisition. The obtained data suggests that numerous individual transmission events lead to the establishment of multistrain infections. These data will be important for the development of epidemiological models in plant virology. 相似文献
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OBJECTIVE: To analyze various possibilities of using dimeric inhibin A (DIA) as a first-trimester marker, during week 13, for diverse sequential strategies together with the combined test (CT) [which uses pregnancy-associated plasma protein A, free beta-human chorionic gonadotrophin and nuchal translucency]. METHOD: We analyzed three sequential strategies (nondisclosure, stepwise and contingent) for measuring DIA in week 13. Multivariate Gaussian modelling was used to estimate second-trimester, false-positive and detection rates. Model parameters were taken from the Serum, Urine and Ultrasound Screening Study (SURUSS) assay. RESULTS: The three sequential strategies provided high and comparable levels of effectiveness, with false-positive rate for fixed detection rate of 85% and detection rate for fixed false-positive rate of 5% values of about 91 and 2%, respectively. The contingent strategy (with two CT risk cutoffs, of 1 in 50 and 1 in 2000) produced a screening-positive rate of 0.8% with CT, while only 23% of the women needed subsequent DIA measurement. CONCLUSIONS: First-trimester sequential screening using CT together with DIA measurement in week 13 is capable of producing results that are comparable with those of the integrated test, with the additional advantage that the final result is obtained earlier. It is recommended that this strategy be evaluated in large-scale prospective studies. Copyright (c) 2008 John Wiley & Sons, Ltd. 相似文献
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Substandard application of preimplantation genetic screening may interfere with its clinical success
Munné S Gianaroli L Tur-Kaspa I Magli C Sandalinas M Grifo J Cram D Kahraman S Verlinsky Y Simpson JL 《Fertility and sterility》2007,88(4):781-784
The intent of this study was to evaluate a recent randomized clinical trial evaluating the effect of preimplantation genetic screening (PGS) that reports a negative effect on pregnancy outcome. This article reviews appropriate PGS techniques and how they differ from the trial in question. A closer look at the clinical trial in question reveals significant lack of expertise in biopsy, cell fixation, genetic analysis, and patient selection. At most, this trial demonstrates that in inexperienced hands, PGS can be detrimental. No other conclusions concerning the effect of PGS on pregnancy results can be drawn from the trial. 相似文献
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Carolina Cavaliéri Gomes Vanessa Fátima Bernardes Marina Gonçalves Diniz Luiz De Marco Ricardo Santiago Gomez 《BMC cancer》2012,12(1):61
Background
Development of accurate therapeutic approaches to salivary gland neoplasms depends on better understanding of their molecular pathogenesis. Tumour growth is regulated by the balance between proliferation and apoptosis. Few studies have investigated apoptosis in salivary tumours relying almost exclusively on immunohistochemistry or TUNEL assay. Furthermore, there is no information regarding the mRNA expression profile of apoptotic genes in salivary tumors. Our objective was to investigate the quantitative expression of BCL-2 (anti-apoptotic), BAX and Caspase3 (pro-apoptotic genes) mRNAs in salivary gland neoplasms and examine the association of these data with tumour size, proliferative activity and p53 staining (parameters associated with a poor prognosis of salivary tumours patients). 相似文献48.
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Helmut Schröder Michelle A. Mendez Santiago F. Gomez Montserrat Fíto Lourdes Ribas Javier Aranceta Lluis Serra-Majem 《Nutrition (Burbank, Los Angeles County, Calif.)》2013,29(11-12):1350-1355
ObjectivesTo determine the impact of energy density on diet quality and anthropometric proxy measures for central body fat in young Spaniards.MethodsData were obtained from a representative national sample of 2513 young Spaniards aged 10 to 24 y. Dietary assessment was performed with a 24-h recall. Adherence to the Mediterranean diet was measured by the KIDMED index. Reduced rank regression analysis was used to identify energy-density dietary patterns. Waist circumferences and height were measured.ResultsPastries and sausages showed the strongest loading for the dietary energy density factor score (DED-FS), with fruits and vegetables at the opposite end of the scale. Multiple linear regression analysis showed a positive association (P < 0.01) of dietary energy density (DED) and the DED-FS with waist circumferences regressed on height and age (WCheight+age) and waist-to-height ratio (WHtR). The adjusted odds ratio for elevated WCheight+age and WHtR increased across quartile distribution of DED (P < 0.001) and DED-FS (P < 0.05). Diet quality characterized by the KIDMED index was negatively associated (P < 0.001) with DED and the DED-FS.ConclusionsHigher DED is a risk for increased central fat distribution and is associated with low adherence to the Mediterranean diet. 相似文献