RESUMO De acordo com estudos realizados, cerca de 10 milhões de pessoas desenvolveram tuberculose em 2018. Desse total, 1,5 milhão de pessoas morreram devido à doença. Procurando estudar o comportamento das sequências do genoma da Mycobacteruim tuberculosis (MTB), bactéria responsável por desenvolver a Tuberculose (TB), foi realizada uma análise aplicando o k-mer (frequência de palavras do DNA). Os valores de k variaram de 1 a 10, pois devido a análise ter sido feita no comprimento total das sequencias, onde cada sequencia é composta por aproximadamente 4 milhões de pares de bases, valores de k acima de 10, a análise é interrompida, como consequência da capacidade do programa. O intuito do trabalho foi de verificar a formação da árvore filogenética em cada k-mer analisado. Os resultados obtidos evidenciaram a formação de grupos distintos em alguns k-mers analisados, levando-se em consideração a linha de corte. Entretanto, em todos os grupos formados as cepas multidroga resistente (MDR) e extensivamente resistente à droga (XDR) permaneceram juntas e separadas das demais cepas.

Abstract According to studies carried out, approximately 10 million people developed tuberculosis in 2018. Of this total, 1.5 million people died from the disease. To study the behavior of the genome sequences of Mycobacterium tuberculosis (MTB), the bacterium responsible for the development of tuberculosis (TB), an analysis was performed using k-mers (DNA word frequency). The k values ranged from 1 to 10, because the analysis was performed on the full length of the sequences, where each sequence is composed of approximately 4 million base pairs, k values above 10, the analysis is interrupted, as consequence of the program's capacity. The aim of this work was to verify the formation of the phylogenetic tree in each k-mer analyzed. The results showed the formation of distinct groups in some k-mers analyzed, taking into account the threshold line. However, in all groups, the multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains remained together and separated from the other strains.

Objective: To analyze the knowledge and acceptance of the elderly person regarding the elaboration of the Advance Directives, their preference in relation to the filling models and the choice of the representative who will replace them in the decision-making process. Methodology: Cross-sectional study carried out by providing participants with two models  of Advance Directives were made available to the participants for completion and applied a questionnaire on knowledge, acceptance, and evaluation of the device. Results: There were 85.63% of the participants who were unaware of the Advance Directives, 98.13% who were unaware of document models, 100% who considered model 1, more complete, to be good or acceptable, and 66.88% who indicated a son as its representative. When asked about the importance of preparing, making available to the population, and passing a law that regulates this right, the participants were assertive respectively by 91.88%, 91.25% and 91.25%. Conclusion: Although lack of knowledge was general among the participants, after clarification there was a high rate of evaluation and acceptance of the Advance Directives, as well as a recommendation for their legalization and availability to the population as a device that contributes to the guarantee of autonomy and human dignity, especially during the end-of-life health care.

Objetivo: Analisar o conhecimento e a aceitação da pessoa idosa acerca da elaboração das Diretivas Antecipadas de Vontade, a sua preferência em relação aos modelos de preenchimento e a escolha do representante que irá substitui-la na tomada de decisão. Metodologia: Estudo transversal realizado por meio da disponibilização aos participantes de dois modelos de Diretivas Antecipadas de Vontade para preenchimento e aplicação de um questionário sobre conhecimento, aceitação e avaliação do dispositivo. Resultados: A grande maioria dos participantes (85,63%) desconhecia as Diretivas Antecipadas de Vontade; 98,13% desconheciam os modelos do documento; 100% consideraram bom ou aceitável o modelo 1, mais completo; e 66,88% indicaram um filho como o seu representante legal. Quando questionados sobre a importância da elaboração, disponibilização à população e aprovação de lei que regulamente esse direito, as respostas foram afirmativas, respectivamente, para 91,88%, 91,25% e 91,25% dos participantes. Conclusão: Embora o desconhecimento fosse geral entre os participantes, após esclarecimento houve elevado índice de avaliação e aceitação das Diretivas Antecipadas de Vontade, bem como recomendação para sua legalização e disponibilização à população como um dispositivo que contribui para a garantia da autonomia e dignidade humana, sobretudo durante a assistência à saúde no final da vida.

Abstract Objective To analyze the knowledge of older individuals in a municipality in the Midwestern region of Santa Catarina regarding the development of Advance Directives, their preferences regarding the available models, and the selection of a representative to make decisions on their behalf. Method Cross-sectional study carried out by providing participants with two models of Advance Directives were made available to the participants for completion and applied a questionnaire on knowledge, acceptance, and evaluation of the device. Results There were 85.63% of the participants who were unaware of the Advance Directives, 98.13% who were unaware of document models, 100% who considered model 1, more complete, to be good or acceptable, and 66.88% who indicated an adult child as its representative. When asked about the importance of preparing, making available to the population, and passing a law that regulates this right, the participants were assertive respectively by 91.88%, 91.25% and 91.25%. Conclusion Most older people were unaware of the AD models, but mentioned model 1, considering it good or acceptable. Most had no difficulties in understanding and recognized the importance of preparing and making AD available to the population, as well as the need for a law to regulate this right. There was a high proportion of participants indicating an adult child as a legal representative, emphasizing the importance of involving the family in this process. These results highlight the need to make older people aware of AD and provide clear and comprehensive models. behalf Crosssectional Cross sectional acceptance device 8563 85 63 85.63 9813 98 13 98.13 100 1 complete acceptable 6688 66 88 66.88 population right 9188 91 91.88% 9125 25 91.25 process 856 8 6 85.6 981 9 98.1 10 668 66.8 918 91.88 912 2 91.2 85. 98. 66. 91.8 91.

Resumo Objetivo Analisar o conhecimento da pessoa idosa em um município do meio oeste catarinense acerca da elaboração das Diretivas Antecipadas de Vontade (DAV), a sua preferência em relação aos modelos de preenchimento e a escolha do representante que irá substitui-la na tomada de decisão. Método Estudo transversal realizado por meio da disponibilização aos participantes de dois modelos de DAV para preenchimento e aplicação de um questionário sobre conhecimento, aceitação e avaliação do dispositivo. Resultados A maioria dos participantes (85,63%) desconhecia as DAV; 98,13% desconheciam os modelos do documento; 100% consideraram bom ou aceitável o modelo 1, mais completo; 66,88% indicaram um filho como representante legal. Questionados sobre a importância da elaboração, disponibilização à população e aprovação de lei que regulamente esse direito, as respostas foram afirmativas, respectivamente, para 91,88%, 91,25% e 91,25% dos participantes. Apenas 5% dos respondentes apontaram dificuldades no entendimento dos modelos, sendo a “linguagem” o item de maior dificuldade. Conclusão A maioria das pessoas idosas desconhecia os modelos de DAV, mas referiram o modelo 1, considerando-o bom ou aceitável. A maioria não teve dificuldades no entendimento e reconheceu a importância da elaboração e disponibilização das DAV à população, assim como a necessidade de uma lei para regulamentar esse direito. Observou-se uma alta proporção de participantes indicando um filho como representante legal, enfatizando a importância de envolver a família nesse processo. Esses resultados ressaltam a necessidade de conscientizar as pessoas idosas sobre as DAV e disponibilizar modelos claros e abrangentes. , (DAV) substituila substitui la decisão dispositivo 85,63% 8563 85 63 (85,63% 9813 98 13 98,13 documento 100 1 completo 6688 66 88 66,88 legal direito afirmativas respectivamente 9188 91 91,88% 9125 25 91,25 5 linguagem “linguagem dificuldade considerandoo considerando Observouse Observou se processo abrangentes (DAV 85,63 856 8 6 (85,63 981 9 98,1 10 668 66,8 918 91,88 912 2 91,2 85,6 (85,6 98, 66, 91,8 91, 85, (85, (85 (8 (

Resumo Considerando que comunicar a morte de paciente a familiares é tarefa difícil para profissionais de saúde, o objetivo desta pesquisa foi identificar na literatura recomendações para reduzir os malefícios dessa situação. Trata-se de estudo qualitativo realizado por meio de revisão bibliográfica nas bases de dados do Portal Capes com a utilização dos termos “morte” e “comunicação”. Os resultados, obtidos em 18 artigos selecionados, foram divididos em três categorias: formação profissional, preparo familiar e prática profissional. Quanto à formação profissional, indicou-se, sobretudo, treinamento por role playing precedido de fundamentação teórica; para o preparo dos familiares, recomendou-se promover diálogo enquanto o paciente vive; em relação à prática profissional, aconselhou-se compartilhar informações entre colegas e adotar medidas para controle emocional. Constatou-se que práticas simuladas, troca de informações entre profissionais, controle emocional dos profissionais e diálogo com e entre familiares contribuem para reduzir o malefício da comunicação de morte.

Abstract Considering that informing family members of a patient’s death is an arduous task for health professionals, the objective of this research was to identify in the literature recommendations to reduce the distress caused by this situation. This is a qualitative study carried out by means of a literature review on the Capes Portal database using the terms “death” and “communication.” The results, obtained from 18 selected articles, were divided into three categories: professional training, family preparation, and professional practice. Regarding professional training, it was indicated, above all, training by role playing preceded by theoretical foundations; for family members’ preparation, the recommendation was to engage in dialogue while the patient is alive; in relation to professional practice, the advice given was information sharing between colleagues and adoption of measures for emotional control. It was found that simulated practices, information sharing between professionals, emotional control of professionals and dialogue with and between family members contribute to reducing the distress when communicating death.

Resumen Teniendo en cuenta que comunicar la muerte de un paciente a familiares es tarea difícil para los profesionales de la salud, el objetivo de esta investigación fue identificar en la literatura recomendaciones para reducir los daños de esa situación. Se trata de un estudio cualitativo realizado por medio de revisión bibliográfica en las bases de datos del portal Capes con la utilización de los Términos “muerte” y “comunicación”. Los resultados, obtenidos a partir de 18 artículos seleccionados, fueron divididos en tres categorías: formación profesional, preparación familiar y práctica profesional. En cuanto a la formación profesional, se indicó, sobre todo, entrenamiento por role playing precedido de fundamentación teórica; para la preparación de los familiares, se recomendó promover el diálogo mientras el paciente vive; en relación con la práctica profesional, se aconsejó compartir informaciones entre compañeros y adoptar medidas de control emocional. Se comprobó que prácticas simuladas, intercambio de informaciones entre profesionales, control emocional de los profesionales y diálogo con y entre familiares contribuyen a reducir el daño de la comunicación de muerte.

Abstract The classifications resulting from phylogenetic analysis are essential tools for evolutionary studies. Phylogenetic is more than a part of evolutionary biology because its underlying philosophy provides a way to see nature, ask questions, and solve problems related to the evolution of organisms. Given the importance of phylogeny, our aim was to devise a method to assess the delimitation of bacterial species. We used the non-decimated discrete wavelet transform. The wavelet function used was Daubechies’ with four null moments, considering seven, four and two decomposition levels. For clustering, the energy (variance) obtained at each level of decomposition and the Mahalanobis distance was used to visualize the dendrogram formation process. Through the analysis, we verified that the gram-positive bacteria were classified well into their respective species, but most gram-negative bacteria did not take into account the more significant amount of energy obtained in scenario two. According to the results, the energy plays an important role in the delimitation of groups of bacterial species.

Abstract APA is a multigene locus that comprises the protein genes of arcelin (Arc), phytohemagglutinin (PHA) or lectin, and an α-amylase inhibitor (α-AI). These genes play essential roles in the defense responses of legume seeds to protect against seed weevils in common bean (P. vulgaris). During the evolution of this complex locus, PHA proteins appeared first, followed by α-AI and Arc proteins. This study compared and analyzed the sequences of three bacterial artificial chromosome (BAC) clones containing APA fragments of the genotypes G02771, BAT93 and DGD1962. These three genotypes are recognized as representative of the crucial steps of APA evolution in common bean. Our findings demonstrated that rearrangements during evolution can be used to characterize the APA locus, but concurrent adjacent gene regions on either side of the APA locus are highly conserved. Part of the instability of the APA locus may be due to the insertion of retroelements and gene conversion. Arc, , (Arc) (PHA lectin αamylase α amylase αAI. αAI AI . (α-AI) P. P (P vulgaris. vulgaris vulgaris) first BAC (BAC G02771 G BAT BAT9 DGD1962 DGD conserved conversion (Arc (α-AI G0277 DGD196 G027 DGD19 G02 DGD1 G0

RESUMO Objetivo Verificar se existe relação de similaridade entre o número de suicídio em países desenvolvidos e emergentes usando a técnica de ondaletas. Métodos Os dados anuais foram obtidos a partir do relatório da Organização Mundial da Saúde (OMS), no período de 1986 a 2015. Para análise, foi empregada a transformada discreta não decimada de ondaleta (NDWT), a função ondaleta aplicada foi a Daubechies com cinco níveis de decomposição. Com relação ao agrupamento, utilizou-se a energia (variância) para analisar os clusters e, para a visualização do processo de clusterização, trabalhamos com o dendograma, no qual se empregou a distância de Mahalanobis. A quantidade de grupos foi definida por meio da função NbCluster. Resultados A partir da análise de cluster , verificou-se a formação de quatros grupos. No qual, Japão e Estados Unidos e Brasil localizam-se em grupos distintos e isolados. E os demais países (Áustria, Bélgica, Chile, Israel, México, Itália e Holanda) em um único grupo. Conclusão Utilizando esse método, foi possível verificar com mais detalhes quais países apresentaram comportamentos semelhantes, mesmo apresentando características bem distintas entre si, tanto socioeconômica, geográfica e climática.

ABSTRACT Objective The aim of this study was to use a wavelet technique to determine whether the number of suicides is similar between developed and emerging countries. Methods Annual data were obtained from World Health Organization (WHO) reports from 1986 to 2015. Discrete nondecimated wavelet transform was used for the analysis, and the Daubechies wavelet function was applied with five-level decomposition. Regarding clustering, energy (variance) was used to analyze the clusters and visualize the clustering process. We constructed a dendrogram using the Mahalanobis distance. The number of groups was set using a specific function in the R program. Results The cluster analysis verified the formation of four groups as follows: Japan, the United States and Brazil were distinct and isolated groups, and other countries (Austria, Belgium, Chile, Israel, Mexico, Italy and the Netherlands) constituted a single group. Conclusion The methods utilized in this paper enabled a detailed verification of countries with similar behaviors despite very distinct socioeconomic, geographic and climate characteristics.

Abstract Phα1β is a neurotoxin purified from spider venom that acts as a high-voltage-activated (HVA) calcium channel blocker. This spider peptide has shown a high selectivity for N-type HVA calcium channels (NVACC) and an analgesic effect in several animal models of pain. Its activity was associated with a reduction in calcium transients, glutamate release, and reactive oxygen species production from the spinal cord tissue and dorsal ganglia root (DRG) in rats and mice. It has been reported that intrathecal (i.t.) administration of Phα1β to treat chronic pain reverted opioid tolerance with a safer profile than ω-conotoxin MVIIA, a highly selective NVACC blocker. Following a recent development of recombinant Phα1β (CTK 01512-2), a new molecular target, TRPA1, the structural arrangement of disulphide bridges, and an effect on glial plasticity have been identified. CTK 01512-2 reproduced the antinociceptive effects of the native toxin not only after the intrathecal but also after the intravenous administration. Herein, we review the Phα1β antinociceptive activity in the most relevant pain models and its mechanisms of action, highlighting the impact of CTK 01512-2 synthesis and its potential for multimodal analgesia.

ABSTRACT Background: Intrathecal injection of voltage-sensitive calcium channel blocker peptide toxins exerts analgesic effect in several animal models of pain. Upon intrathecal administration, recombinant Phα1β exerts the same analgesic effects as the those of the native toxin. However, from a clinical perspective, the intrathecal administration limits the use of anesthetic drugs in patients. Therefore, this study aimed to investigate the possible antinociceptive effect of intravenous recombinant Phα1β in rat models of neuropathic pain, as well as its side effects on motor, cardiac (heart rate and blood pressure), and biochemical parameters. Methods: Male Wistar rats and male Balb-C mice were used in this study. Giotto Biotech® synthesized the recombinant version of Phα1β using Escherichia coli expression. In rats, neuropathic pain was induced by chronic constriction of the sciatic nerve and paclitaxel-induced acute and chronic pain. Mechanical sensitivity was evaluated using von Frey filaments. A radiotelemeter transmitter (TA11PA-C10; Data Sciences, St. Paul, MN, USA) was placed on the left carotid of mice for investigation of cardiovascular side effects. Locomotor activity data were evaluated using the open-field paradigm, and serum CKMB, TGO, TGP, LDH, lactate, creatinine, and urea levels were examined. Results: Intravenous administration of recombinant Phα1β toxin induced analgesia for up to 4 h, with ED50 of 0.02 (0.01-0.03) mg/kg, and reached the maximal effect (Emax = 100% antinociception) at a dose of 0.2 mg/kg. No significant changes were observed in any of the evaluated motor, cardiac or biochemical parameters. Conclusion: Our data suggest that intravenous administration of recombinant Phα1β may be feasible for drug-induced analgesia, without causing any severe side effects.

Abstract INTRODUCTION: Tuberculosis is listed among the top 10 causes of deaths worldwide. The resistant strains causing this disease have been considered to be responsible for public health emergencies and health security threats. As stated by the World Health Organization (WHO), around 558,000 different cases coupled with resistance to rifampicin (the most operative first-line drug) have been estimated to date. Therefore, in order to detect the resistant strains using the genomes of Mycobacterium tuberculosis (MTB), we propose a new methodology for the analysis of genomic similarities that associate the different levels of decomposition of the genome (discrete non-decimated wavelet transform) and the Hurst exponent. METHODS: The signals corresponding to the ten analyzed sequences were obtained by assessing GC content, and then these signals were decomposed using the discrete non-decimated wavelet transform along with the Daubechies wavelet with four null moments at five levels of decomposition. The Hurst exponent was calculated at each decomposition level using five different methods. The cluster analysis was performed using the results obtained for the Hurst exponent. RESULTS: The aggregated variance, differenced aggregated variance, and aggregated absolute value methods presented the formation of three groups, whereas the Peng and R/S methods presented the formation of two groups. The aggregated variance method exhibited the best results with respect to the group formation between similar strains. CONCLUSION: The evaluation of Hurst exponent associated with discrete non-decimated wavelet transform can be used as a measure of similarity between genome sequences, thus leading to a refinement in the analysis.

Abstract We propose to evaluate genome similarity by combining discrete non-decimated wavelet transform (NDWT) and elastic net. The wavelets represent a signal with levels of detail, that is, hidden components are detected by means of the decomposition of this signal, where each level provides a different characteristic. The main feature of the elastic net is the grouping of correlated variables where the number of predictors is greater than the number of observations. The combination of these two methodologies applied in the clustering analysis of the Mycobacterium tuberculosis genome strains proved very effective, being able to identify clusters at each level of decomposition.

ABSTRACT Jatropha is a potential oilseed crop, which requires mitigating factors such as the low genetic variability of the species. The solution runs through the research of Brazilian germplasm. Attention should be given to the germplasm of jatropha the north of Minas Gerais, because this is the oldest national collection and because this region may be a regions of jatropha diversity due to selection pressure arising from environmental adversities. Therefore, the objective of this study was to investigate the genetic diversity of 48 accessions of collection from Empresa de Pesquisa Agropecuária de Minas Gerais (EPAMIG), using SSR and ISSR markers. The results showed low genetic diversity, but some individuals stood out as J. mollissima (48), J. podagrica (47), Mexican accessions (42, 43, 44 and 45) and some national accessions (28, 29, 41 and 46). Therefore, aiming to increase the genetic variability and improve the effectiveness of jatropha breeding programs, it is suggested to explore such as parental accessions to generate commercial hybrids. This fact implies the possibility to support future production of jatropha, since this culture may be an important source of income, especially for small farmers living in semiarid regions of Brazil.

O morango é uma importante cultura no Brasil. Contudo, a maioria dos genótipos comerciais cultivados foram desenvolvidos em outros países, com pouca adaptação aos ambientes locais. Neste trabalho, o marcador molecular do tipo sequências internas simples repetidas foi utilizado para avaliar a variabilidade genética e a segregação dos perfis genéticos de 84 híbridos de morango obtidos pelo programa de melhoramento desenvolvido pela Empresa de Pesquisa Agropecuária de Minas Gerais. Os híbridos foram obtidos dos cruzamentos entre 'Toyonoka' x 'Sweet Charlie', 'Camino Real' x 'Sweet Charlie', 'Oso Grande' x 'Sweet Charlie', 'Oso Grande' x 'Toyonoka', 'Dover' x 'Oso Grande' e 'Camino Real' x 'Toyonoka', sendo avaliados 14 genótipos escolhidos aleatoriamente para cada combinação híbrida. Os resultados obtidos indicam que os perfis genéticos entre os genótipos híbridos dentro de cada cruzamento são bem diversos, provavelmente devido a elevada heterozigosidade da constituição genômica de cada parental envolvido. Isso indica a existência de suficiente diversidade genética entre os híbridos que pode facilitar a seleção de novos cultivares com características agronômicas adequadas.

The strawberry is an important agricultural crop in Brazil. However, most of the commercial genotypes currently in cultivation in Brazil were developed in other countries with environmental adaptations often inadequate for the regional conditions. In this work, inter-simple sequence repeat markers were used to determine the genetic variability and the loci segregation profiles of 84 strawberry hybrids obtained from a genetic breeding program at the 'Empresa de Pesquisa Agropecuária de Minas Gerais.' The hybrids were produced from crosses involving the following progenitors: 'Toyonoka' x 'Sweet Charlie', 'Camino Real' x 'Sweet Charlie', 'Oso Grande' x 'Sweet Charlie', 'Oso Grande' x 'Toyonoka', 'Dover' x 'Oso Grande', and 'Camino Real' x 'Toyonoka'. Fourteen genotypes were randomly sampled for each hybrid combination and evaluated. The results showed that the genetic profiles of the hybrids from each test cross were very diverse, most likely due to the high heterozygosity of the genome of each progenitor involved, which might indicate the presence of adequate genetic diversity among the hybrids to allow for the selection of new cultivars with agronomic traits that are more suitable to environmental conditions in Brazil.

O objetivo deste trabalho foi avaliar o efeito da luz na germinação e desenvolvimento in vitro de embriões de 11 genótipos de oliveira, cultivados em meio MS. Os frutos foram coletados e os embriões de suas sementes extraídos assepticamente. Utilizaram-se duas condições experimentais de incubação: presença de luz, fornecida em sala de crescimento, com 16 h de luz com irradiância média de 36 µmol m-2 s-1, e ausência de luz, simulada em câmara de germinação tipo B.O.D.; ambos os tratamentos em temperatura de 25 ºC. Inicialmente, caracterizaram-se morfologicamente os frutos e sementes dos genótipos de oliveira, com medição do comprimento e diâmetro. Avaliaram-se o índice de velocidade de germinação (IVG), percentagem de germinação, comprimento de parte aérea, número de folhas e entrenós das plântulas. Maior IVG e percentagem de germinação foram observados em condições de incubação, na presença de luz para o genótipo 'Cerignola 131'. Maior comprimento de parte aérea e maior número de folhas e de entrenós das plântulas foram observados no genótipo 'Salomé 488', independentemente da condição de incubação.

The purpose of this study was to evaluate the influence of light in the in vitro development of embryos from eleven olive genotypes on MS medium. The fruits were collected, and their embryos were extracted aseptically. Two experimental conditions of incubation were used: the presence of light, in a growth room at 25±1ºC, irradiance of 36 µmol m-2 s-1 and a photoperiod of 16 hours, and the absence of light using BOD temperature of 25 ºC. The germination was evaluated (speed index and percentage ratio) at the 10th day of incubation. Additionally, at the 45th day, the shoot length, the number of leaves and the internodes of seedlings were recorded. The best speed index and germination percentage occurred in conditions of incubation in the presence of light. The genotype 'Salome', access 488, presented the greatest shoot length, and the highest number of leaves and internodes, independent of the incubation condition.

Vários métodos de extração de DNA genômico para a identificação e caracterização da diversidade genética em diferentes espécies de plantas são rotineiramente aplicados durante a análise molecular. Entretanto, a presença de compostos indesejáveis, tais como polifenóis e polissacarídeos, é um dos maiores problemas que ocorrem durante o isolamento e purificação de DNA de alta qualidade em plantas. Dessa forma, o sucesso no desenvolvimento de métodos de extração de DNA rápidos e acurados é crucial para produzir amostras puras. Folhas de genótipos de morangueiro (Fragaria ananassa) têm elevado conteúdo de polissacarídeos e polifenóis que aumentam a viscosidade da amostra e reduzem a qualidade do DNA, interferindo no desempenho da PCR. Neste estudo, avaliamos a qualidade e a quantidade de DNA genômico extraído de folhas jovens de morangueiro após a liofilização do tecido e a maceração na presença de polivinilpirrolidona (PVP). O método CTAB foi utilizado como procedimento de referência e foi modificado para melhorar a extração do DNA. As modificações consistiram na liofilização do tecido a baixa temperatura até que ele tivesse sido desidratado completamente, associada à adição de PVP durante a maceração do tecido no nitrogênio líquido. Os resultados demonstraram a eficiência e a confiabilidade do método modificado comparado ao método não modificado, indicando que a combinação da liofilização com PVP melhora a qualidade e quantidade do DNA extraído de folhas de morangueiro.

Several extraction methods of genomic DNA for identification and characterization of genetic diversity in different plant species are routinely applied during molecular analysis. However, the presence of undesirable compounds such as polyphenols and polysaccharides is one of the biggest problems faced during the isolation and purification of high quality DNA in plants. Therefore, achievement of fast and accurate methods for DNA extraction is crucial in order to produce pure samples. Leaves of strawberry genotypes (Fragaria ananassa) have high contents of polysaccharides and polyphenols which increase the sample viscosity and decrease the DNA quality, interfering with the PCR performance. Thereby, in this study we evaluated the quality and amount of genomic DNA extracted from young leaves of strawberry after tissue lyophilization and maceration in presence of polivinilpirrolidone (PVP). The CTAB method was used as reference procedure and it was modified to improve the DNA extraction. The modifications consisted of tissue lyophilization overnight until it was completely freeze-dried and addition of PVP during the tissue maceration in liquid nitrogen. The results showed the efficiency and reliability of the modified method compared to the unmodified method, indicating that combination of lyophilization and PVP improve the quality and amount of the DNA extracted from strawberry leaves.