The objectives of this work were to evaluate the genetic variability of Meloidogyne enterolobii by molecular markers, and develop species-specific molecular markers for application in detection. Sixteen M. enterolobii isolates from different geographical regions (Brazil and other countries) and hosts were used in this study. The identification and purification of the populations were carried out based on isoenzyme phenotype. The DNA amplification of the intergenic region (IGS) of the rDNA and of the region between the cytochrome oxidase subunit II (COII) and 16S rRNA genes (mtDNA) produced specific fragments of the expected size for this nematode, i.e. 780 and 705 bp, respectively. Intraspecific variability among the isolates was evaluated with three different neutral molecular markers: AFLP, ISSR and RAPD. The results showed a low level of diversity among the isolates tested, indicating that M. enterolobii is a genetically homogeneous root-knot nematode species. The RAPD method allowed the identification of a species-specific RAPD fragment for M. enterolobii. This fragment was cloned and sequenced, and from the sequence obtained, a set of primers was designed and tested. The amplification of a 520-bp-long fragment occurred only for the 16 isolates of M. enterolobii and not for the 10 other Meloidogyne species tested. In addition, positive detection was achieved in a single individual female, egg-mass and second stage juvenile of this nematode. This SCAR species-specific marker for M. enterolobii represents a new molecular tool to be used in the detection of this nematode from field samples and as a routine diagnostic test for quarantine devices.
Cancer is one of the leading causes of death worldwide. Although several drugs are used clinically, some tumors either do not respond or are resistant to the existing pharmacotherapy, thus justifying the search for new drugs. Ursolic acid (UA) is a triterpene found in different plant species that has been shown to possess significant antitumor activity. However, UA presents a low solubility in aqueous medium, which presents a barrier to its biological applications. In this context, the use of liposomes presents a promising strategy to deliver UA and allow for its intravenous administration. In this work, long-circulating and pH-sensitive liposomes containing UA (SpHL-UA) were developed, and their chemical and physicochemical properties were evaluated. SpHL-UA presented adequate properties, including a mean diameter of 191.1 ± 6.4 nm, a zeta potential of 1.2 ± 1.4 mV, and a UA entrapment of 0.77 ± 0.01 mg/mL. Moreover, this formulation showed a good stability after having been stored for 2 months at 4°C. The viability studies on breast (MDA-MB-231) and prostate (LNCaP) cancer cell lines demonstrated that SpHL-UA treatment significantly inhibited cancer cell proliferation. Therefore, the results of the present work suggest the applicability of SpHL-UA as a new and promising anticancer formulation.
Caracterização genética de seis plantéis comerciais de tilápia (Oreochromis) utilizando marcadores microssatélitesPalavras-chave: tilápia, microssatélite, distância genética.
ABSTRACTTwo hundred and thirty five individuals from six commercial stocks of tilapias (Ceará, Chitralada, Israel, Nilótica, Taiwan and Red) from the Southeastern region of the country were genetically characterized using five microsatellite loci. The results suggest large genetic difference among the stocks, estimated through the fixation allele index (Fst = 0.3263), and a considerable loss of heterozigosity occurs in most of the stocks, according to the population inbreeding coefficient (Fis=0.0486). The Israel and Nilótica stocks were genetically similar (Ig=0.6663), while Chitralada and Taiwan showed less genes in common (Ig=0.2463). The Red stock was the most distinct stock.
RESUMOPara avaliar a viabilidade da metodologia da Reação em Cadeia da Polimerase associada com o Polimorfismo de Fragmentos de DNA (PCR-RFLP) na identificação de fraude intencional e contaminação acidental em produtos cárneos de origem bubalina, in natura e processados, foram testadas amostras puras e amostras de carnes com misturas controladas, produzidas em laboratório, com adição de 1%, 5%, 10% e 50% de carne bovina em carne de búfalo, homogeneizada crua e em amostras autoclavada. Foram comparados, ainda, diferentes métodos de extração, usando um kit comercial e a técnica clássica, utilizando fenol/clorofórmio. O resultado estatístico foi obtido por tabela de contingência, analisada pelo teste do qui-quadrado ( 2 ) e do exato de Fisher. A especificidade encontrada foi altamente significativa (P<0,0001). Observou-se também sensibilidade altamente significativa nas diluições a partir de 10% (P<0,0001). A técnica tem alta especificidade e sensibilidade para detectar até mesmo contaminação de 1%, mas a repetibilidade desse resultado impede a aplicação oficial desse método para a inspeção de contaminação acidental, sendo recomendada somente para inspeção de fraude a partir de 10% de substituição. Em carnes autoclavadas, a eficácia do teste é menor. A técnica pode ser empregada para certificação de produto específico (selo de identidade de espécie).
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