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OBJECTIVE: To evaluate the effect of activated charcoal-based (AC) products on color alteration, remineralizing potential and surface roughness of dental enamel. MATERIALS AND METHODS: Bovine incisors were cut into 6 × 6 × 2 mm fragments. Initial color (EasyShade, Vita) and surface roughness (Surfcorder SE1700, Kosakalab) readings were performed. Fragments were separated into five groups (n = 17) according to the treatment: Control: Fluoride toothpaste (Colgate Total 12, Colgate); Charcoal + NaF: AC toothpaste (ACT) with sodium fluoride (Colgate Natural Extracts, Colgate); Charcoal + MFP + n-HA: ACT with sodium monofluorophosphate and nanohydroxyapatite (Black is White, Curaprox); Charcoal: Fluoride-free ACT (ProActive, Hinode); and Charcoal powder: AC powder. Simulated toothbrushing was performed and final color and surface roughness readings were obtained. Fragments were then polished, and initial microhardness (HMV-2, Shimatzu) readings were done. Samples were artificially demineralized and brushed again. Final microhardness readings were taken. Data were statistically analyzed. RESULTS: Fluoride-free charcoal presented the lowest surface roughness alteration (p < 0.05). Charcoal powder had the lowest color change (p < 0.05) and negative values for whiteness index for dentistry alteration. All the groups presented values below whiteness acceptability threshold and negative relative microhardness values. Control showed the highest remineralizing potential (p < 0.05). CONCLUSIONS: ACPs did not produce color alteration different from the fluoride toothpaste, except for Charcoal powder that caused less color change. ACPs caused surface roughness alteration similar to the fluoride toothpaste. ACT with fluoride and AC powder did not have remineralizing potential. CLINICAL SIGNIFICANCE: Activated charcoal-based products (ACP) promise effective tooth whitening and quick results, without teeth damage. In addition, some ACPs contain fluoride in toothpaste composition and promise rehardening potential. However, ACPs are not as effective as other whitening agents and can alter the surface roughness of the enamel. Even if the ACPs contain fluoride or other remineralizing agents, they might be ineffective.

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ABSTRACT: In this study Pyricularia spp., P. oryzae and the P. oryzae pathotype Triticum (PoT) were detected and identified in leaf segments of forage and invasive grasses located in or next to wheat fields. In 2018 and 2019, 66 samples of lesion leaf segments of Urochloa and other grasses were collected in Londrina (PR), Patos de Minas (MG), and Uberaba (MG). The detection and/or identification of the pathogens on the samples was conducted using moist chamber procedures and with the primers MoT3 and Pot2 by PCR. There were DNA amplification with the primer MoT3 (specific for PoT) for 13 (19.69%) of the samples, all of them from Urochloa. The finding that Urochloa hosts PoT at a relatively high rate raises concerns about the importance which these plants may have on the wheat blast cycle as an alternative host for the pathogen and/or source of inoculum for the disease.

RESUMO: Neste estudo Pyricularia spp., P. oryzae e o patótipo Triticum (PoT) de P. oryzae foram detectados e identificados em segmentos foliares de forrageiras e gramíneas invasoras de lavouras de trigo. Em 2018 e 2019, foram coletadas 66 amostras de segmentos foliares lesionados de Urochloa e outras gramíneas em Londrina (PR), Patos de Minas (MG) e Uberaba (MG). A detecção e/ou identificação dos patógenos nas amostras foi realizada por meio de procedimentos de câmara úmida e com os iniciadores MoT3 e Pot2 por PCR. Houve amplificações de DNA com o primer MoT3 (específico para PoT) em 13 (19,69%) das amostras, todas provenientes da Urochloa. O resultado de que Urochloa hospeda PoT em uma taxa relativamente alta levanta preocupações sobre a importância que essas plantas podem ter no ciclo de brusone do trigo como hospedeiro intermediário para o patógeno e / ou fonte de inóculo para a doença.

RESUMO

In this study Pyricularia spp., P. oryzae and the P. oryzae pathotype Triticum (PoT) were detected and identified in leaf segments of forage and invasive grasses located in or next to wheat fields. In 2018 and 2019, 66 samples of lesion leaf segments of Urochloa and other grasses were collected in Londrina (PR), Patos de Minas (MG), and Uberaba (MG). The detection and/or identification of the pathogens on the samples was conducted using moist chamber procedures and with the primers MoT3 and Pot2 by PCR. There were DNA amplification with the primer MoT3 (specific for PoT) for 13 (19.69%) of the samples, all of them from Urochloa. The finding that Urochloa hosts PoT at a relatively high rate raises concerns about the importance which these plants may have on the wheat blast cycle as an alternative host for the pathogen and/or source of inoculum for the disease.

Neste estudo Pyricularia spp., P. oryzae e o patótipo Triticum (PoT) de P. oryzae foram detectados e identificados em segmentos foliares de forrageiras e gramíneas invasoras de lavouras de trigo. Em 2018 e 2019, foram coletadas 66 amostras de segmentos foliares lesionados de Urochloa e outras gramíneas em Londrina (PR), Patos de Minas (MG) e Uberaba (MG). A detecção e/ou identificação dos patógenos nas amostras foi realizada por meio de procedimentos de câmara úmida e com os iniciadores MoT3 e Pot2 por PCR. Houve amplificações de DNA com o primer MoT3 (específico para PoT) em 13 (19,69%) das amostras, todas provenientes da Urochloa. O resultado de que Urochloa hospeda PoT em uma taxa relativamente alta levanta preocupações sobre a importância que essas plantas podem ter no ciclo de brusone do trigo como hospedeiro intermediário para o patógeno e / ou fonte de inóculo para a doença.

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In the last seven years, Kaniadakis statistics, or κ-statistics, have been applied in reactor physics to obtain generalized nuclear data, which can encompass, for instance, situations that lie outside thermal equilibrium. In this sense, numerical and analytical solutions were developed for the Doppler broadening function using the κ-statistics. However, the accuracy and robustness of the developed solutions contemplating the κ distribution can only be appropriately verified if applied inside an official nuclear data processing code to calculate neutron cross-sections. Hence, the present work inserts an analytical solution for the deformed Doppler broadening cross-section inside the nuclear data processing code FRENDY, developed by the Japan Atomic Energy Agency. To do that, we applied a new computational method called the Faddeeva package, developed by MIT, to calculate error functions present in the analytical function. With this deformed solution inserted in the code, we were able to calculate, for the first time, deformed radiative capture cross-section data for four different nuclides. The usage of the Faddeeva package brought more accurate results when compared to other standard packages, reducing the percentage errors in the tail zone in relation to the numerical solution. The deformed cross-section data agreed with the expected behavior compared to the Maxwell-Boltzmann.

RESUMO

The first report of wheat blast in the world was in Brazil, in 1986. Since then, a great effort has been made towards the development of wheat cultivars resistant to this disease, which is caused by the fungus Pyricularia oryzae Triticum (PoT). The objective of this research was to (i) evaluate the resistance of wheat genotypes to blast and (ii) verify the correlation between disease severity on wheat spikes and sporulation rate of PoT on spike rachises. Plants of 40 cultivars grown in pots, at the flowering stage (stage 65 on the Zadoks scale), were inoculated with a suspension of conidia of a PoT isolate representative of the main variant of the fungus reported in Brazil. Severity of blast on the spikes at 5 and 7 days after inoculation (dai) and the rate of sporulation of the fungus on the rachis (conidia per g of rachis) were evaluated. Eighty percent of the cultivars that were classified in the group with the lowest sporulation rate were also classified in the group with the highest resistance at 7 dai. However, the correlation coefficients of the analysis established between the cultivar severity at 5 and 7 dai averages and the PoT sporulation rate averages were not significant (r=0.2464 and r=0.2047, respectively). Results obtained represent the updated characterization to blast of wheat cultivars in Brazil and constitute an important exploratory framework for the evaluation of the reaction of wheat genotypes based on the sporulation rate of PoT on their tissues.

O primeiro relato da brusone do trigo no mundo foi no Brasil, em 1986. Desde então, tem-se realizado um esforço muito grande com vistas ao desenvolvimento de cultivares de trigo resistentes a esta doença, a qual é causada pelo fungo Pyricularia oryzae Triticum (PoT). O objetivo deste trabalho foi de (i) avaliar a resistência de genótipos de trigo à brusone e (ii) verificar a correlação entre severidade da doença em espigas e taxa de esporulação de PoT em ráquis de espigas. Plantas de 40 cultivares brasileiras de trigo crescidas em vasos, no estádio de florescimento (estádio 65 da escala de Zadoks), foram submetidas à inoculação com uma suspensão de conídios de um isolado de PoT representativo da principal variante do fungo encontrada no Brasil. A severidade de brusone nas espigas aos cinco e sete dias após a inoculação (dai) e a taxa de esporulação do fungo nas ráquis (conídios por g de ráquis) foram avaliadas. Oitenta por cento das cultivares que foram classificadas no grupo com menor taxa de esporulação também foram classificadas no grupo de maior resistência aos sete dai. Entretanto, os coeficientes de correlação da análise estabelecida entre as médias de severidade das cultivares aos cinco e sete dai e as médias da taxa de esporulação de PoT não foram significativos (r=0,2464 e r=0,2047, respectivamente). Os resultados obtidos representam a caracterização atualizada da reação à brusone de cultivares de trigo do Brasil e constituem-se em importante marco exploratório da avaliação da reação de genótipos de trigo baseado na taxa de esporulação de PoT em seus tecidos.

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Wheat blast, caused by Pyricularia oryzae Triticum lineage, is a major constraint to wheat production, mainly in the tropics of Brazil, where severe epidemics have been more frequent. We analyzed disease and wheat yield data from 42 uniform field trials conducted over 9 years (2012 to 2020) to assess whether the percent control and yield response were influenced by fungicide type, region (tropical or subtropical), and year. Six treatments were selected, all evaluated in at least 19 trials. Two fungicides were applied as solo active ingredients (MANCozeb, and TEBUconazole), and four were premixes (AZOXystrobin plus TEBU, TriFLoXystrobin plus PROThioconazole, TFLX plus TEBU, and PYRAclostrobin plus EPOXiconazole). Percent control, calculated from back-transforming estimates by a meta-analysis network model fitted to the log of the means, ranged from 43 to 58%, with all but PYRA plus EPOX showing efficacy >52% on average, not differing among them. The variation in both efficacy and yield response was explained by region, and all but TEBU performed better in the subtropics than in the tropics. Yield response from using three sequential sprays was approximately two times greater in the subtropics (319 to 532 kg/ha) than in the tropics (149 to 241.3 kg/ha). No significant decline in fungicide efficacy or yield response was observed in 9 years of study for any of the fungicides. These results reinforce the need to improve control by adopting an integrated management approach in the tropics given poorer performance and lower profitability, especially for the premixes, than in the subtropics.

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Fusarium head blight (FHB) is a disease of wheat (Triticum aestivum L.) that causes major yield losses in South America, as well as many other wheat growing regions around the world. FHB results in low quality, contaminated grain due to the production of mycotoxins such as deoxynivalenol (DON). In Brazil, FHB outbreaks are increasing in frequency and are currently controlled by fungicides which are costly and potentially harmful to the wider environment. To identify the genetic basis of resistance to FHB in Brazilian wheat, two mapping populations (Anahuac 75 × BR 18-Terena and BR 18-Terena × BRS 179) segregating for FHB resistance were phenotyped and quantitative trait loci (QTL) analysis was undertaken to identify genomic regions associated with FHB-related traits. A total of 14 QTL associated with FHB visual symptoms were identified, each of which explained 3.7-17.3% of the phenotypic variance. Two of these QTL were stable across environments. This suggests FHB resistance in Anahuac 75, BR 18-Terena and BRS 179 is controlled by multiple genetic loci that confer relatively minor differences in resistance. A major, novel QTL associated with DON accumulation was also identified on chromosome 4B (17.8% of the phenotypic variance), as well as a major QTL associated with thousand-grain weight on chromosome 6B (16.8% phenotypic variance). These QTL could be useful breeding targets, when pyramided with major sources of resistance such as Fhb1, to improve grain quality and reduce the reliance on fungicides in Brazil and other countries affected by FHB.

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A 36-year-old-woman, smoker, without other relevant medical history, presented with symptoms of dyspnea, right localized chest pain, and non-productive cough. On the emergency department, the chest X-ray was interpreted as a giant right pneumothorax and a chest drain was inserted. Thoracic computed tomography demonstrated a giant emphysematous bulla with 23 cm on her right upper lobe. We report the first uniportal video-assisted thoracic surgery bullectomy for a bulla greater than 20 cm, in a patient with vanishing lung syndrome.

Una mujer de 36 años de edad, fumadora, se presentó en la sala de emergencias por disnea, tos y dolor torácico derecho. La radiografía fue interpretada como neumotórax y se colocó un tubo de drenaje. La tomografía computarizada del tórax mostró una bulla enfisematosa gigante, de aproximadamente 23 cm. Reportamos el primer caso de bullectomía por uniportal VATS en una paciente con síndrome del pulmón evanescente que presentaba una bulla mayor de 20 cm.

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BACKGROUND: Wheat blast, caused by Magnaporthe oryzae Triticum (MoT) pathotype, is a global threat to wheat (Triticum aestivum L.) production. Few blast resistance (R) genes have been identified to date, therefore assessing potential sources of resistance in wheat is important. The Brazilian wheat cultivar BR 18-Terena is considered one of the best sources of resistance to blast and has been widely used in Brazilian breeding programmes, however the underlying genetics of this resistance are unknown. RESULTS: BR 18-Terena was used as the common parent in the development of two recombinant inbred line (RIL) F6 populations with the Brazilian cultivars Anahuac 75 and BRS 179. Populations were phenotyped for resistance at the seedling and heading stage using the sequenced MoT isolate BR32, with transgressive segregation being observed. Genetic maps containing 1779 and 1318 markers, were produced for the Anahuac 75 × BR 18-Terena and BR 18-Terena × BRS 179 populations, respectively. Five quantitative trait loci (QTL) associated with seedling resistance, on chromosomes 2B, 4B (2 QTL), 5A and 6A, were identified, as were four QTL associated with heading stage resistance (1A, 2B, 4A and 5A). Seedling and heading stage QTL did not co-locate, despite a significant positive correlation between these traits, indicating that resistance at these developmental stages is likely to be controlled by different genes. BR 18-Terena provided the resistant allele for six QTL, at both developmental stages, with the largest phenotypic effect conferred by a QTL being 24.8% suggesting that BR 18-Terena possesses quantitative resistance. Haplotype analysis of 100 Brazilian wheat cultivars indicates that 11.0% of cultivars already possess a BR 18-Terena-like haplotype for more than one of the identified heading stage QTL. CONCLUSIONS: This study suggests that BR 18-Terena possesses quantitative resistance to wheat blast, with nine QTL associated with resistance at either the seedling or heading stage being detected. Wheat blast resistance is also largely tissue-specific. Identification of durable quantitative resistances which can be combined with race-specific R gene-mediated resistance is critical to effectively control wheat blast. Collectively, this work facilitates marker-assisted selection to develop new varieties for cultivation in regions at risk from this emerging disease.

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Wheat blast is known for developing itself more intensely under relatively high temperature conditions but many aspects related to its epidemiology remain unknown. The objective of this research was to evaluate the sporulative capacity of Pyricularia oryzae Triticum (Pot), the causal agent of wheat blast, in tissues of wheat plants under different temperatures degrees. Wheat plants of the cultivar Anahuac 75, susceptible to blast, were inoculated in the stage of flowering with conidial suspensions (105 conidia/mL) of the Pot isolates Py 12.1.209 and Py 12.1.132. Seven days after the inoculation, plants were cut in the following segments: leaves, stems and rachis (with blast severity ranging from 40 to 60%). Groups of each one of the three plant segments with the lesions were disposed in Petri-dish moist chambers, that were submitted to six different temperature treatments (18, 21, 24, 27, 30 and 33 °C). The most appropriate model that related the conidia production with temperature was identified in the evaluations conducted with stems. The established equations allowed identifying that the highest production of conidia of Pot occurs between 24 and 27 °C.(AU)

Sabe-se que a brusone do trigo ocorre preferencialmente em condições de temperaturas relativamente altas, porém muitos aspectos sobre a epidemiologia desta doença ainda permanecem desconhecidos. O objetivo deste trabalho foi avaliar a capacidade esporulativa de Pyricularia oryzae Triticum (Pot) em tecidos de plantas de trigo sob diferentes temperaturas. Plantas de trigo do cultivar Anahuac 75, suscetível à brusone, foram inoculadas no estádio do florescimento com suspensões de conídios dos isolados Py 12.1.209 e Py 12.1.132 de Pot (105 conídios/mL). Sete dias após a inoculação, as plantas foram cortadas e separadas em três tipos de segmentos: colmos, folhas e ráquis (com severidade de brusone variando de 40 a 60%). Um grupo de cada desses três tipos de segmentos de planta contendo lesões foi disposto em câmara úmida. O material foi acondicionado em seis níveis de temperatura: 18, 21, 24, 27, 30 e 33 °C. O modelo mais apropriado que relacionou a produção de conídios com temperatura foi identificado nas avaliações feitas nas amostras de colmo. As equações estabelecidas permitiram identificar que a maior produção de conídios de Pot ocorreu entre as temperaturas de 24 e 27 °C.(AU)

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El schwannoma es un tumor neurogénico que se presenta más frecuentemente en el ángulo costovertebral del mediastino posterior, pero también en otras localizaciones dentro del tórax. Habitualmente suele ser una masa única, encapsulada, bien definida, con un tamaño aproximado 2 a 10 cm. Presentamos el caso de un paciente de 66 años, derivado a nuestro hospital por una masa de 13 cm localizada en el hemitórax inferior izquierdo. Se realizó una biopsia, y la resonancia magnética corroboró el diagnóstico de un tumor mediastínico gigante de la vaina neural. Se procedió a su resección completa sin complicaciones.

Schwannomas are neurogenic tumors, commonly located in the costovertebral angle of the posterior mediastinum, but with many intrathoracic locations. They usually present as a solitary, well-circumscribed and encapsulated mass with a size between 2 and 10 cm. We report a case of a 66-year-old male, referred to our hospital for a mass located at the left lower hemithorax with 13 cm in size. A percutaneous biopsy was performed, and magnetic resonance imaging confirmed the diagnosis of a resectable giant mediastinal nerve sheath tumor. Surgery was performed without complications.

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ABSTRACT: Wheat blast is known for developing itself more intensely under relatively high temperature conditions but many aspects related to its epidemiology remain unknown. The objective of this research was to evaluate the sporulative capacity of Pyricularia oryzae Triticum (Pot), the causal agent of wheat blast, in tissues of wheat plants under different temperatures degrees. Wheat plants of the cultivar Anahuac 75, susceptible to blast, were inoculated in the stage of flowering with conidial suspensions (105 conidia/mL) of the Pot isolates Py 12.1.209 and Py 12.1.132. Seven days after the inoculation, plants were cut in the following segments: leaves, stems and rachis (with blast severity ranging from 40 to 60%). Groups of each one of the three plant segments with the lesions were disposed in Petri-dish moist chambers, that were submitted to six different temperature treatments (18, 21, 24, 27, 30 and 33 °C). The most appropriate model that related the conidia production with temperature was identified in the evaluations conducted with stems. The established equations allowed identifying that the highest production of conidia of Pot occurs between 24 and 27 °C.

RESUMO: Sabe-se que a brusone do trigo ocorre preferencialmente em condições de temperaturas relativamente altas, porém muitos aspectos sobre a epidemiologia desta doença ainda permanecem desconhecidos. O objetivo deste trabalho foi avaliar a capacidade esporulativa de Pyricularia oryzae Triticum (Pot) em tecidos de plantas de trigo sob diferentes temperaturas. Plantas de trigo do cultivar Anahuac 75, suscetível à brusone, foram inoculadas no estádio do florescimento com suspensões de conídios dos isolados Py 12.1.209 e Py 12.1.132 de Pot (105 conídios/mL). Sete dias após a inoculação, as plantas foram cortadas e separadas em três tipos de segmentos: colmos, folhas e ráquis (com severidade de brusone variando de 40 a 60%). Um grupo de cada desses três tipos de segmentos de planta contendo lesões foi disposto em câmara úmida. O material foi acondicionado em seis níveis de temperatura: 18, 21, 24, 27, 30 e 33 °C. O modelo mais apropriado que relacionou a produção de conídios com temperatura foi identificado nas avaliações feitas nas amostras de colmo. As equações estabelecidas permitiram identificar que a maior produção de conídios de Pot ocorreu entre as temperaturas de 24 e 27 °C.

RESUMO

Wheat blast was first reported in Brazil in 1985. It spread rapidly across the wheat cropping areas of Brazil to become the most important biotic constraint on wheat production in the region. The alarming appearance of wheat blast in Bangladesh in 2016 greatly increased the urgency to understand this disease, including its causes and consequences. Here, we summarize the current state of knowledge of wheat blast and aim to identify the most important gaps in our understanding of the disease. We also propose a research agenda that aims to improve the management of wheat blast and limit its threat to global wheat production.

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Delineating species and epidemic lineages in fungal plant pathogens is critical to our understanding of disease emergence and the structure of fungal biodiversity and also informs international regulatory decisions. Pyricularia oryzae (syn. Magnaporthe oryzae) is a multihost pathogen that infects multiple grasses and cereals, is responsible for the most damaging rice disease (rice blast), and is of growing concern due to the recent introduction of wheat blast to Bangladesh from South America. However, the genetic structure and evolutionary history of M. oryzae, including the possible existence of cryptic phylogenetic species, remain poorly defined. Here, we use whole-genome sequence information for 76 M. oryzae isolates sampled from 12 grass and cereal genera to infer the population structure of M. oryzae and to reassess the species status of wheat-infecting populations of the fungus. Species recognition based on genealogical concordance, using published data or extracting previously used loci from genome assemblies, failed to confirm a prior assignment of wheat blast isolates to a new species (Pyricularia graminis-tritici). Inference of population subdivisions revealed multiple divergent lineages within M. oryzae, each preferentially associated with one host genus, suggesting incipient speciation following host shift or host range expansion. Analyses of gene flow, taking into account the possibility of incomplete lineage sorting, revealed that genetic exchanges have contributed to the makeup of multiple lineages within M. oryzae These findings provide greater understanding of the ecoevolutionary factors that underlie the diversification of M. oryzae and highlight the practicality of genomic data for epidemiological surveillance in this important multihost pathogen.IMPORTANCE Infection of novel hosts is a major route for disease emergence by pathogenic microorganisms. Understanding the evolutionary history of multihost pathogens is therefore important to better predict the likely spread and emergence of new diseases. Magnaporthe oryzae is a multihost fungus that causes serious cereal diseases, including the devastating rice blast disease and wheat blast, a cause of growing concern due to its recent spread from South America to Asia. Using whole-genome analysis of 76 fungal strains from different hosts, we have documented the divergence of M. oryzae into numerous lineages, each infecting a limited number of host species. Our analyses provide evidence that interlineage gene flow has contributed to the genetic makeup of multiple M. oryzae lineages within the same species. Plant health surveillance is therefore warranted to safeguard against disease emergence in regions where multiple lineages of the fungus are in contact with one another.

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Blast, caused by Pyricularia oryzae, threats black (Avena strigosa) and white (A. sativa) oats in Brazil. Little is known about the reaction of Brazilian oat cultivars to blast and if there is a relationship between the response of cultivars to the disease at seedling and adult plant stages. The goals of this research were to verify (a) the reaction of black and white Brazilian oat cultivars to infection of P. oryzae and (b) if the response to blast on seedling leaves and panicles was correlated. Seedlings and adult plants of 13 oat cultivars were inoculated with a conidial suspension of one P. oryzae isolate obtained from a black oat cultivar. The cultivars were classified according to blast severity on the leaf seedlings and panicles estimated by visual estimation. Two experiments were conducted for each one of the two evaluated stages. Cultivars with lower value to blast severity on seedling leaves were ‘UPFA Gaudéria (25.82%) and ‘UPF 18 (24.88%) and, on panicles, ‘BRS Centauro (31.63%). Coefficients of Pearson, Spearman, and Kendall obtained from correlation analyses between blast severity on seedling leaves and panicles were -0.21232, -0.35714, and -0.30769, respectively (non-significant at 0.05). Lack of correlation between the responses of these oat cultivars to blast on seedling leaves and panicles be considered in the management of the disease in the field and the generation of new oat cultivars.(AU)

A brusone, causada por Pyricularia oryzae, ameaça as culturas da aveia preta (Avena strigosa) e branca (A. sativa) no Brasil. Sabe-se pouco sobre a reação das cultivares brasileiras de aveia à brusone e se existe relação entre a resposta destas cultivares à doença nos estádios de plântula e de planta adulta. Os objetivos deste trabalho foram: (a) verificar a reação de cultivares brasileiras de aveia à infecção de P. oryzae e; (b) se existe relação entre a resposta à brusone dessas cultivares nos estádios de plântula e de planta adulta. Plântulas e plantas adultas de 13 cultivares de aveia foram inoculadas com uma suspensão de conídios de um isolado de P. oryzae obtido de uma planta de uma cultivar de aveia preta. As cultivares foram classificadas de acordo com a estimativa visual da severidade da doença nas folhas das plântulas e nas panículas das plantas adultas. Dois experimentos foram conduzidos para cada um dos estádios avaliados. As cultivares com menor severidade de brusone nas plântulas foram a ‘Gaudéria UPFA (25,82%) e a ‘UPF 18 (24,88%) e, nas panículas, foi a ‘BRS Centauro (31,63%). Os coeficientes de Pearson, Spearman e Kendall obtidos da análise de correlação entre os dois estádios avaliados foram -0,21232, -0,35714 e -0,30769, respectivamente (todos sem significância estatística à 0,05). A falta de correlação entre as respostas das cultivares de aveia à brusone, em plântulas e panículas, constitui-se em informação a ser considerada no manejo da doença, no campo e na geração de novas cultivares de aveia.(AU)

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Blast, caused by Pyricularia oryzae, threats black (Avena strigosa) and white (A. sativa) oats in Brazil. Little is known about the reaction of Brazilian oat cultivars to blast and if there is a relationship between the response of cultivars to the disease at seedling and adult plant stages. The goals of this research were to verify (a) the reaction of black and white Brazilian oat cultivars to infection of P. oryzae and (b) if the response to blast on seedling leaves and panicles was correlated. Seedlings and adult plants of 13 oat cultivars were inoculated with a conidial suspension of one P. oryzae isolate obtained from a black oat cultivar. The cultivars were classified according to blast severity on the leaf seedlings and panicles estimated by visual estimation. Two experiments were conducted for each one of the two evaluated stages. Cultivars with lower value to blast severity on seedling leaves were ‘UPFA Gaudéria’ (25.82%) and ‘UPF 18’ (24.88%) and, on panicles, ‘BRS Centauro’ (31.63%). Coefficients of Pearson, Spearman, and Kendall obtained from correlation analyses between blast severity on seedling leaves and panicles were -0.21232, -0.35714, and -0.30769, respectively (non-significant at 0.05). Lack of correlation between the responses of these oat cultivars to blast on seedling leaves and panicles be considered in the management of the disease in the field and the generation of new oat cultivars.

A brusone, causada por Pyricularia oryzae, ameaça as culturas da aveia preta (Avena strigosa) e branca (A. sativa) no Brasil. Sabe-se pouco sobre a reação das cultivares brasileiras de aveia à brusone e se existe relação entre a resposta destas cultivares à doença nos estádios de plântula e de planta adulta. Os objetivos deste trabalho foram: (a) verificar a reação de cultivares brasileiras de aveia à infecção de P. oryzae e; (b) se existe relação entre a resposta à brusone dessas cultivares nos estádios de plântula e de planta adulta. Plântulas e plantas adultas de 13 cultivares de aveia foram inoculadas com uma suspensão de conídios de um isolado de P. oryzae obtido de uma planta de uma cultivar de aveia preta. As cultivares foram classificadas de acordo com a estimativa visual da severidade da doença nas folhas das plântulas e nas panículas das plantas adultas. Dois experimentos foram conduzidos para cada um dos estádios avaliados. As cultivares com menor severidade de brusone nas plântulas foram a ‘Gaudéria UPFA’ (25,82%) e a ‘UPF 18’ (24,88%) e, nas panículas, foi a ‘BRS Centauro’ (31,63%). Os coeficientes de Pearson, Spearman e Kendall obtidos da análise de correlação entre os dois estádios avaliados foram -0,21232, -0,35714 e -0,30769, respectivamente (todos sem significância estatística à 0,05). A falta de correlação entre as respostas das cultivares de aveia à brusone, em plântulas e panículas, constitui-se em informação a ser considerada no manejo da doença, no campo e na geração de novas cultivares de aveia.

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ABSTRACT: Blast, caused by Pyricularia oryzae, threats black (Avena strigosa) and white (A. sativa) oats in Brazil. Little is known about the reaction of Brazilian oat cultivars to blast and if there is a relationship between the response of cultivars to the disease at seedling and adult plant stages. The goals of this research were to verify (a) the reaction of black and white Brazilian oat cultivars to infection of P. oryzae and (b) if the response to blast on seedling leaves and panicles was correlated. Seedlings and adult plants of 13 oat cultivars were inoculated with a conidial suspension of one P. oryzae isolate obtained from a black oat cultivar. The cultivars were classified according to blast severity on the leaf seedlings and panicles estimated by visual estimation. Two experiments were conducted for each one of the two evaluated stages. Cultivars with lower value to blast severity on seedling leaves were 'UPFA Gaudéria' (25.82%) and 'UPF 18' (24.88%) and, on panicles, 'BRS Centauro' (31.63%). Coefficients of Pearson, Spearman, and Kendall obtained from correlation analyses between blast severity on seedling leaves and panicles were -0.21232, -0.35714, and -0.30769, respectively (non-significant at 0.05). Lack of correlation between the responses of these oat cultivars to blast on seedling leaves and panicles be considered in the management of the disease in the field and the generation of new oat cultivars.

RESUMO: A brusone, causada por Pyricularia oryzae, ameaça as culturas da aveia preta (Avena strigosa) e branca (A. sativa) no Brasil. Sabe-se pouco sobre a reação das cultivares brasileiras de aveia à brusone e se existe relação entre a resposta destas cultivares à doença nos estádios de plântula e de planta adulta. Os objetivos deste trabalho foram: (a) verificar a reação de cultivares brasileiras de aveia à infecção de P. oryzae e; (b) se existe relação entre a resposta à brusone dessas cultivares nos estádios de plântula e de planta adulta. Plântulas e plantas adultas de 13 cultivares de aveia foram inoculadas com uma suspensão de conídios de um isolado de P. oryzae obtido de uma planta de uma cultivar de aveia preta. As cultivares foram classificadas de acordo com a estimativa visual da severidade da doença nas folhas das plântulas e nas panículas das plantas adultas. Dois experimentos foram conduzidos para cada um dos estádios avaliados. As cultivares com menor severidade de brusone nas plântulas foram a 'Gaudéria UPFA' (25,82%) e a 'UPF 18' (24,88%) e, nas panículas, foi a 'BRS Centauro' (31,63%). Os coeficientes de Pearson, Spearman e Kendall obtidos da análise de correlação entre os dois estádios avaliados foram -0,21232, -0,35714 e -0,30769, respectivamente (todos sem significância estatística à 0,05). A falta de correlação entre as respostas das cultivares de aveia à brusone, em plântulas e panículas, constitui-se em informação a ser considerada no manejo da doença, no campo e na geração de novas cultivares de aveia.

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Liver cancer is the sixth most commonly occurring cancer globally, and the main histological type is hepatocellular carcinoma. This type of neoplasia has a poor prognosis due to a high rate of recurrence and intrahepatic metastasis, which are closely are closely associated with the angiogenic process. Vascular endothelial growth factor (VEGF), which is under the control of hypoxia inducible factor-1α (HIF-1α), stimulates the proliferation of endothelial cells and increases cell permeability, promoting the growth, spread and metastasis of tumors. Melatonin, the main hormone secreted by the pineal gland, may have a significant role in tumor suppression and has demonstrated antiangiogenic and antimetastatic effects. The aim of the present study was to analyze the cell viability, migration and invasion, as well as the expression of proangiogenic proteins VEGF and HIF-1α, in HepG2 hepatocarcinoma cells, following treatment with melatonin. Cells were cultured and cell viability was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The expression of proangiogenic proteins VEGF and HIF-1α, under conditions of normoxia and hypoxia, was verified using immunocytochemistry and quantified by densitometry. The analysis of the processes of cell migration and invasion was performed in a Boyden chamber. The MTT assay revealed a reduction in cell viability (P=0.018) following treatment with 1 mM melatonin for 24 h. The expression of proangiogenic proteins VEGF and HIF-1α was reduced in cells treated with 1 mM melatonin for 24 h in normoxic (P<0.001) and hypoxic (P<0.001) conditions, compared with the control group and with induced hypoxia alone. The rate of cell migration and invasion was additionally reduced in cells treated with 1 mM melatonin for 48 h when compared with the control group (P=0.496). The results of the present study suggest that melatonin may have an antiproliferative, antiangiogenic and antimetastatic role in hepatocarcinoma cells and may present a novel therapeutic option for the treatment of liver cancer.

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INTRODUCTION: Helicobacter pylori infection is associated with gastritis, peptic ulcer disease and gastric carcinoma. The severity of damage is determined by the interplay between environmental/behavioral factors, bacterial pathogenicity genes and host genetic polymorphisms that can influence the secretion levels of inflammatory cytokines. Accordingly, this study aimed to identify polymorphisms in the IL-1B and IL-1RN genes and their associations with H. pylori infection, cagA gene of H. pylori, and gastroduodenal diseases. METHODOLOGY: Gastric biopsy samples from 151 patients infected with H. pylori and 76 uninfected individuals were analyzed. H. pylori infection was diagnosed by histology and PCR. Polymorphisms at positions -511, -31 and +3954 of the IL-1B gene were detected by PCR-RFLP, and an analysis of the VNTR polymorphism of the IL-1RN gene was performed by PCR. RESULTS: It was observed that the presence of the T/T genotype at position -511 and the C/C genotype at position -31 were associated with H. pylori infection and with an increased risk of gastritis in H. pylori-positive patients. Additionally, strains from patients H. pylori-positive carrying the cagA gene was significantly related with the T/T genotype at position -511 of IL-1B.  No association of polymorphisms at position +3954 of IL-1B and in the IL-1RN with H. pylori infection and with risk of severe gastric diseases was found. CONCLUSIONS: We demonstrated that polymorphisms in the promoter region of the IL-1B gene (at positions -511 and -31) are associated with an enhanced risk of H. pylori infection as well as gastritis in H. pylori-positive patients.

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