Ecotoxicological effects of commercial herbicides on the reproductive system of aquatic arthropod Limnocoris submontandoni (Hemiptera: Naucoridae) / Efeitos ecotoxicológicos de herbicidas comerciais no sistema reprodutivo do artrópode aquático Limnocoris submontandoni (Hemiptera: Naucoridae)

Abstract Worldwide, conventional agriculture makes extensive use of pesticides. Although the effects of herbicides are relatively well known in terms of environmental impacts on non-target organisms, there is very little scientific evidence regarding the impacts of herbicide residues on aquatic arthropods from tropical conservation areas. This study evaluates for the first time the toxicity of the herbicides ametryn, atrazine, and clomazone on the aquatic insect Limnocoris submontandoni (Hemiptera: Naucoridae). The lethal concentration (LC50) of herbicides was evaluated for these insects, as well as the effect of the herbicides on the insects' tissues and testicles. The estimated LC50 was 1012.41, 192.42, and 46.09 mg/L for clomazone, atrazine, and ametryn, respectively. Spermatocyte and spermatid changes were observed under the effect of atrazine, and effects on spermatogenesis were observed for some concentrations of clomazone, with apparent recovery after a short time. Our results provide useful information on the effects of herbicide residues in aquatic systems. This information can help minimize the risk of long-term reproductive effects in non-target species that have been previously overlooked in ecotoxicology studies.

Resumo Em todo o mundo, a agricultura convencional faz uso extensivo de pesticidas. Embora os efeitos dos herbicidas sejam relativamente bem conhecidos em termos de impactos ambientais em organismos não-alvo, há pouca evidência científica sobre os impactos de resíduos de herbicidas em artrópodes aquáticos de áreas de conservação tropicais. Este estudo avalia pela primeira vez a toxicidade dos herbicidas ametryn, atrazine e clomazone sobre o inseto aquático Limnocoris submontandoni (Hemiptera: Naucoridae). A concentração letal (LC50) de herbicidas foi avaliada para esses insetos, bem como o efeito dos herbicidas nos tecidos e testículos dos insetos. A LC50 estimada foi de 1012,41, 192,42 e 46,09 mg/L para clomazone, atrazine e ametryn, respectivamente. Alterações nos espermatócitos e espermátides foram observadas sob o efeito de atrazine, e efeitos na espermatogênese foram observados para algumas concentrações de clomazone, com aparente recuperação após um curto período de tempo. Nossos resultados fornecem informações úteis sobre os efeitos de resíduos de herbicidas em sistemas aquáticos. Essas informações podem ajudar a minimizar o risco de efeitos reprodutivos de longo prazo em espécies não-alvo que foram negligenciadas anteriormente em estudos de ecotoxicologia.

Ecotoxicological effects of commercial herbicides on the reproductive system of aquatic arthropod Limnocoris submontandoni (Hemiptera: Naucoridae)

Abstract Worldwide, conventional agriculture makes extensive use of pesticides. Although the effects of herbicides are relatively well known in terms of environmental impacts on non-target organisms, there is very little scientific evidence regarding the impacts of herbicide residues on aquatic arthropods from tropical conservation areas. This study evaluates for the first time the toxicity of the herbicides ametryn, atrazine, and clomazone on the aquatic insect Limnocoris submontandoni (Hemiptera: Naucoridae). The lethal concentration (LC50) of herbicides was evaluated for these insects, as well as the effect of the herbicides on the insects tissues and testicles. The estimated LC50 was 1012.41, 192.42, and 46.09 mg/L for clomazone, atrazine, and ametryn, respectively. Spermatocyte and spermatid changes were observed under the effect of atrazine, and effects on spermatogenesis were observed for some concentrations of clomazone, with apparent recovery after a short time. Our results provide useful information on the effects of herbicide residues in aquatic systems. This information can help minimize the risk of long-term reproductive effects in non-target species that have been previously overlooked in ecotoxicology studies.

Resumo Em todo o mundo, a agricultura convencional faz uso extensivo de pesticidas. Embora os efeitos dos herbicidas sejam relativamente bem conhecidos em termos de impactos ambientais em organismos não-alvo, há pouca evidência científica sobre os impactos de resíduos de herbicidas em artrópodes aquáticos de áreas de conservação tropicais. Este estudo avalia pela primeira vez a toxicidade dos herbicidas ametryn, atrazine e clomazone sobre o inseto aquático Limnocoris submontandoni (Hemiptera: Naucoridae). A concentração letal (LC50) de herbicidas foi avaliada para esses insetos, bem como o efeito dos herbicidas nos tecidos e testículos dos insetos. A LC50 estimada foi de 1012,41, 192,42 e 46,09 mg/L para clomazone, atrazine e ametryn, respectivamente. Alterações nos espermatócitos e espermátides foram observadas sob o efeito de atrazine, e efeitos na espermatogênese foram observados para algumas concentrações de clomazone, com aparente recuperação após um curto período de tempo. Nossos resultados fornecem informações úteis sobre os efeitos de resíduos de herbicidas em sistemas aquáticos. Essas informações podem ajudar a minimizar o risco de efeitos reprodutivos de longo prazo em espécies não-alvo que foram negligenciadas anteriormente em estudos de ecotoxicologia.

Structure-activity relationship, molecular docking, and molecular dynamic studies of diterpenes from marine natural products with anti-HIV activity.

HIV-1 infection is a global epidemic whose treatment is limited majorly by viral resistance and adverse effects. Natural products from algae have been studied for many years, including antiviral, being an alternative to anti-HIV drug design. Since the isolation of natural products can be a hurdle, molecular modeling is an important tool to study these compounds. Herein, structure-activity relationship, molecular docking, and molecular dynamic studies were performed to direct the studies of ten marine natural products with anti-HIV activity. In the structure-activity relationship, descriptors were identified associating the anti-HIV activity of five diterpenes with possible action on the reverse transcriptase allosteric site. These diterpenes were evaluated by molecular docking, and it was identified that only dolabelladienetriol interacted in the allosteric site. Molecular dynamics suggested that the dolabelladienetriol might interfere with the viral RNA binding to HIV-1 RT by inducing a conformational change of the enzyme. Also, in silico ADMET simulations predicts that the dolabelladienetriol present a high potential to be successfully developed as a drug. Thus, applying in silico approaches was possible to suggest potential anti-HIV compounds derived from marine natural products.Communicated by Ramaswamy H. Sarma.

Ecotoxicological effects of commercial herbicides on the reproductive system of aquatic arthropod Limnocoris submontandoni (Hemiptera: Naucoridae).

Worldwide, conventional agriculture makes extensive use of pesticides. Although the effects of herbicides are relatively well known in terms of environmental impacts on non-target organisms, there is very little scientific evidence regarding the impacts of herbicide residues on aquatic arthropods from tropical conservation areas. This study evaluates for the first time the toxicity of the herbicides ametryn, atrazine, and clomazone on the aquatic insect Limnocoris submontandoni (Hemiptera: Naucoridae). The lethal concentration (LC50) of herbicides was evaluated for these insects, as well as the effect of the herbicides on the insects' tissues and testicles. The estimated LC50 was 1012.41, 192.42, and 46.09 mg/L for clomazone, atrazine, and ametryn, respectively. Spermatocyte and spermatid changes were observed under the effect of atrazine, and effects on spermatogenesis were observed for some concentrations of clomazone, with apparent recovery after a short time. Our results provide useful information on the effects of herbicide residues in aquatic systems. This information can help minimize the risk of long-term reproductive effects in non-target species that have been previously overlooked in ecotoxicology studies.

Evaluation of corn hybrids for silage grown in different locations / Avaliação de híbridos de milho para silagem cultivados em diferentes locais

The aim of this study was to evaluate the yield, morphometric and chemical characteristics, and the digestibility of various corn hybrids cultivated in different locations for silage production. Four corn hybrids were grown: P2866H, P3456H, P30R50VYH and P4285YHR, in four locations, defined as farm A; B; C and D. The hybrid P4285YHR presented the highest plant and ear insertion heights (2.72m, 1.52m respectively), with a minimum registered height of 2.63 m and 1.42 m, for plant and ear insertion height, and for that reason it presented the highest yield of fresh biomass (78,089kg ha-1). The TND values showed trend very close to that observed in the DISMS of the whole-plant, with hybrid P3456H presenting the highest estimated value (68.74%), and the hybrid P4285YHR the lowest among them (65.25%). In general, lower fibrous carbohydrates and lignin content, higher fibrous carbohydrates content, together with satisfactory grains participation in the plant structure led to a greater dry matter digestibility. Hybrids with lower plant heights do not necessarily have lower dry biomass yields, but hybrids of greater height and with high stem and leaf participation tend to have a higher aFDN content and less dry matter digestibility.(AU)

O objetivo deste estudo foi avaliar o desempenho produtivo e as características morfométricas e químicas, além da digestibilidade de diferentes híbridos de milho cultivados em diferentes locais para produção de silagem. Foram cultivados quatro híbridos de milho: P2866H, P3456H, P30R50VYH e P4285YHR, em quatro locais, definidos como propriedades A; B; C e D. O híbrido P4285YHR apresentou as maiores alturas de planta e de inserção de espiga (2,72m, 1,52m, respectivamente), com altura mínima registrada, nos diferentes locais, de 2,63m e 1,42m, para altura de planta e inserção de espiga, e, por isso, apresentou o maior rendimento de biomassa fresca (78.089kg ha-1). Os valores calculados de NDT mostraram tendência muito próxima àquela observada na DISMS da planta inteira, tendo o híbrido P3456H apresentado o maior valor estimado (68,74%), e o híbrido P4285YHR o menor entre eles (65,25%). Em geral, menores concentrações de carboidratos fibrosos e lignina, maior teor de carboidratos fibrosos, juntamente com satisfatória participação de grãos na estrutura da planta, conduzem a uma maior digestibilidade da matéria seca. Híbridos com menores alturas de planta não necessariamente apresentam menores rendimentos de biomassa seca, mas híbridos de maior altura e com alta participação de colmo e folhas tendem a apresentar maior teor de aFDN e menor digestibilidade da matéria seca.(AU)

Effect of sealing on the feed out face of trench silos on the performance of confined calves / [Efeito da vedação na porção inicial de silos trincheiras sobre o desempenho de novilhos confinados]

This study aimed to evaluate the productive performance, dry matter intake, apparent digestibility and ingestive behavior of feedlot calves fed corn silage from the feed out face of trench silos with different types of sealing. The animals were divided into three treatments with four repetitions: Conventional seal - double-sided polyethylene of 110µm thickness; Double-sided seal - double-sided polyethylene of 200µm thickness; and Double seal - composed of double face polyethylene with a thickness of 80µm superimposed on a polyamide translucent vacuum film with a thickness of 20µm. The use of double face sealing provided 12.63% increase in average daily gain and improved food conversion by 0.62 percentage points. The apparent digestibility of the diet with double-face sealing system silage was 4.30% higher than the diet with double-face sealing silage and 11.00% higher than the diet with conventional sealing silage. It is recommended to use the double face sealing with 200µm polyethylene and double face sealing with 80µm thick polyethylene on top of a 20µm thick polyamide translucent vacuum film.(AU)

Objetivou-se avaliar o desempenho produtivo, o consumo de matéria seca, a digestibilidade aparente e o comportamento ingestivo de novilhos confinados, alimentados com silagem de milho da porção inicial de silos do tipo trincheira, conservada sob distintos tipos de vedação. Os animais foram divididos em três tratamentos, com quatro repetições: vedação convencional - polietileno tipo dupla face, com espessura de 110µm; vedação dupla face - polietileno tipo dupla face, com espessura de 200µm; e dupla vedação - polietileno tipo dupla face, com espessura de 80µm sobreposto a um filme vácuo translúcido de poliamida, com espessura de 20µm. O uso da vedação dupla face proporcionou incremento de 12,63% no ganho de peso médio diário e melhorou em 0,62 ponto percentual a conversão alimentar. A digestibilidade aparente da dieta com silagem do sistema de vedação dupla face foi 4,30% superior em relação à dieta com silagem da dupla vedação e 11,00% superior à dieta com silagem da vedação convencional. Recomenda-se a utilização tanto da vedação dupla face com polietileno de 200µm quanto da dupla vedação com polietileno tipo dupla face, com espessura de 80µm, sobreposto a um filme vácuo translúcido de poliamida com espessura de 20µm.(AU)

Production and nutritional quality of black oat forage grown in different population stands under a successive cutting regime / [Produção e qualidade nutricional da forragem de aveia-preta cultivada em diferentes estandes populacionais sob regime de cortes sucessivos]

The present study aimed to evaluate the agronomic productive and qualitative traits of forage of black oats grown in different stands of plants. The experimental design was a 2 x 2 factorial randomized complete block design consisting of four treatments, two plant stands (175 and 350 plants m2) associated with two successive cutting periods (vegetative and full vegetative) and four replications. The stand of plants did not influence the production of dry biomass; with 175 plants m2, we obtained a compensatory effect by the greater number of tillers m2-1 and/or tiller plant-1. The population stand influenced the chemical parameters, where 175 plants m2 resulted in forage with higher contents of hemicellulose and total digestible nutrients and a lower content of neutral detergent fiber. In the comparison between cuts, the first cut compared to the second presented higher values of crude protein (26.53%). It is recommended that the black oat be cultivated with a population stand of 175 plants m2 for generating an increase in the number of tillers m2-1 and tillers plant-1, in addition to improving the in situ dry matter digestibility of the whole plant, without causing reduction of production of dry biomass per unit area.(AU)

O presente trabalho objetivou avaliar as características agronômicas produtivas e qualitativas da forragem da aveia-preta submetida ao cultivo com diferentes estandes populacionais. O delineamento experimental foi de blocos ao acaso, em esquema fatorial 2 x 2, composto por quatro tratamentos, sendo dois estandes (175 e 350 plantas m2), associado a duas épocas de corte sucessivas (vegetativo e pleno vegetativo) e a quatro repetições. Os estandes populacionais não influenciaram a produção de biomassa seca, pois, com 175 plantas m2, obteve-se efeito compensatório por maior número de perfilhos m2-1 e/ou perfilho planta-1. O estande populacional influenciou os parâmetros bromatológicos, o qual, com 175 plantas m2, gerou produção de forragem com maiores teores de hemicelulose e de nutrientes digestíveis totais e um menor teor de fibra em detergente neutro. Na comparação entre os cortes, o primeiro corte, comparado ao segundo corte, apresentou maiores valores de proteína bruta (26,53%). Recomenda-se a aveia-preta cultivada com estande populacional de 175 plantas m2 por gerar aumento do número de perfilhos m2-1 e perfilhos planta-1, além de melhorar a digestibilidade in situ da matéria seca da planta inteira, sem causar redução de produção de biomassa seca por unidade de área.(AU)

Fiber composition and digestibility of fodder in different ryegrass fields submitted to different harvesting management systems / [Composição da fibra e digestibilidade da forragem de diferentes cultivares de azevém submetidos a diferentes sistemas de manejo de colheita]

This essay aims to evaluate the composition of fiber in neutral detergent, digestibility of plant components, as well as ruminal disappearance rate of fodder dry matter from five ryegrass fields submitted to different cut systems for the production of haylage. The experimental design was the randomized blocks one, at a 5 x 3 factorial scheme, with five cultivars (cv.) of ryegrass Lolium multiflorum (cv. Barjumbo, cv. BarHQ, cv. Ribeye, cv. Potro and cv. Willians) associated with three harvesting management systems: 1- single harvesting system at a pre-floral stage; 2 - double harvesting system, with a cut at vegetative stage and another at pre-floral stage; and 3 - triple harvesting system, with a cut at vegetative stage, a cut at full vegetative stage and a cut at pre-floral stage, with three repetitions each. Similarities were noticed on the results of fodder digestibility of different fields, however, cv. Potro presented a higher ruminal disappearance rate after 48 hours, with 69.27%. Generally, the harvesting management system with the increase of ryegrass cut frequency determined increments on the percentage of lignin and the reduction in the concentration of total nutrients and dry matter digestibility of the resulting hylage.(AU)

O objetivo do presente trabalho foi avaliar a composição da fibra em detergente neutro, digestibilidade dos componentes da planta, bem como a taxa de desaparecimento ruminal da matéria seca da forragem de cinco cultivares de azevém submetidos a diferentes sistemas de cortes para produção de silagem pré-secada. O delineamento experimental foi em blocos ao acaso,, em um fatorial 5 x 3, sendo cinco cultivares de azevém Lolium multiflorum (cv. Barjumbo, cv. BarHQ, cv. Ribeye, cv. Potro e cv. Willians) associados a três sistemas de manejo de colheita: 1 - sistema com única colheita no estádio de pré-florescimento; 2 - sistema com uma colheita no estádio vegetativo e outra no estádio de pré-florescimento; e 3 - sistema com uma colheita no estádio vegetativo, uma no estádio pleno vegetativo e outra no estádio de pré-florescimento, com três repetições cada. Notou-se similaridade entre os resultados de digestibilidade da forragem entre os cultivares, porém o cv. Potro apresentou a maior taxa de desaparecimento ruminal após 48 horas, com 69,27%. De maneira geral, o sistema de manejo de colheita mostrou que o aumento do número de cortes do azevém determinou incrementos nos teores de lignina e redução na concentração de nutrientes digestíveis totais e da digestibilidade da matéria seca nas silagens pré-secadas resultantes.(AU)

Yeast culture in the diet of feedlot steers: performance, carcass traits and feeding behavior / Cultura de leveduras na dieta de novilhos confinados: desempenho, características da carcaça e comportamento ingestivo

This study aimed to evaluate the performance, apparent digestibility of diet, ingestive behavior which occurred in two moments, carcass traits, being evaluated constituent and non-carcass components, and also the effect the yeast culture could promote in the peripheral temperature of rumen, hull and body temperature. The diets consisted of a constant ratio of 50% forage (maize silage) and 50% concentrate. Thirty-six steers, ½ Angus Nelore, with average age of 11 months and average initial body weight of 339.5±10kg were used in the experiment. The inclusion of yeast culture promoted a higher daily dry matter intake (8.83 vs 9.35kg day-1) and, consequently, a better daily weight gain (1,143 vs. 1,325kg day-1) in the initial feedlot phase, with no difference in other periods. The apparent digestibility of the diet containing yeast culture was higher than the control diet (69.69 versus 68.32%, respectively), and its use did not interfere with the feeding behavior of the animals. Based on our findings, supplementation with yeast culture may bring positive results in the initial feedlot phase.(AU)

O objetivo deste estudo foi avaliar o desempenho; a digestibilidade aparente da dieta; o comportamento oral ingestivo, o qual ocorreu em dois momentos, as características de carcaça, sendo avaliados componentes integrantes e não integrantes da carcaça; bem como o efeito que a cultura de leveduras pudesse promover perante a temperatura periférica de rúmen, casco e temperatura corpórea, sendo aferida por meio da temperatura retal. As dietas foram constituídas em uma constante relação de 50% de volumoso (silagem de milho) e 50% de concentrado. Utilizaram-se no experimento 36 novilhos, ½ sangue Angus Nelore, com idade média de 11 meses e peso vivo médio inicial de 339,5 ± 10kg. O uso de cultura de leveduras promoveu maior consumo diário de matéria seca (8,83 contra 9,35 kg dia-1) e consequentemente melhor ganho de peso diário (1,143 contra 1,325kg dia-1) na fase inicial do confinamento, não havendo diferença nos demais períodos. A digestibilidade aparente da dieta que continha cultura de leveduras foi superior à da dieta controle (69,69 contra 68,32%, respectivamente), e seu uso não interferiu no comportamento ingestivo dos animais. Com base nos resultados do presente estudo, a suplementação com cultura de leveduras pode trazer resultados positivos na fase inicial de confinamento.(AU)

Pathological profiles of systemic infections by Panton-Valentine leukocidin-positive, methicillin-resistant Staphylococcus aureus strains in a murine model.

AIMS: Staphylococcus aureus is one of the most common pathogens in hospital environment and community. Panton-Valentine leukocidin (PVL) production is clinically associated with skin abscesses, soft tissues infections, bacteraemia and sepsis. This study aimed to investigate the effects of the presence of genes lukF/S-PV coding for PVL, in histological and haematological features during systemic infection, using a Swiss mice experimental model. METHODS AND RESULTS: Experiments were performed using 25 mice distributed into five experimental groups, intravenously inoculated with 50 µl suspensions at density 1·0 × 107  CFU per ml of strains: methicillin-susceptible (MSSA) and pvl-negative strains isolated from nasal colonization; MSSA pvl-positive strains isolated from nasal colonization; methicillin-resistant (MRSA) and pvl-positive strains isolated from peripheral blood of a patient with severe pulmonary infection; and a MRSA pvl-positive strains isolated from a peripheral blood culture of a patient with bacteraemia. Haematological analysis was performed at 24, 48, 72 and 96 h post-infection. Morphoanatomy and histopathological analyses were performed at 96 h post-infection. For all S. aureus strains tested, the capability of intravenous dissemination and survival into mice tissues was demonstrated. Inflammatory processes at different levels were related to the presence of pvl genes, and included alterations in the format, size and colour of the organs. Staphylococcus aureus pvl-positive strains were detected in greater numbers in the organs of the infected animals. CONCLUSIONS: The pvl-positive strains isolated from blood cultures were capable to induce the greatest modifications in both haematological and histopathological profiles, and seemed to aggravate the systemic infections. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings are valuable in characterizing infections caused by S. aureus in humans and murine.

Performance, carcass characteristics and ingestive behavior of steers fed with silages of different maize hybrids / Desempenho, características da carcaça e comportamento ingestivo de novilhos alimentados com silagens de diferentes híbridos de milho

The objective of this study was to evaluate the performance, carcass characteristics and ingestive behavior of feedlot steers fed with three maize hybrids: Maximus VIP3, Defender VIP and Feroz VIP. The experiment lasted 112 days, weighing animals four times, every 28 days. The experimental diets were formulated and constituted by maize silage and pelletized ration in a 50:50 ratio (dry basis). Regardless of the hybrid used, there was an increase in the intake of dry matter with the advance in feedlot evaluation period (9.15, 9.14, 9.35 and 9.59kg day-1, in the first, second, third and fourth weighing, respectively). The type of maize hybrid silage influenced weight gain of animals differently, with a final mean of 1.413kg for animals fed with Maximus VIP3, 1,375kg for those fed with Defender VIP and 1,184kg for those fed with Feroz VIP. The animals fed with Feroz VIP hybrid silage showed higher carcass gain efficiency and were more active in the number of times they went to the feeder. Although the three evaluated hybrids resulted in good animal performance, the carcass characteristics did not change; nevertheless, the hybrid Maximus VIP3 is recommended for its superior bromatological composition.(AU)

O objetivo deste trabalho foi avaliar desempenho, características da carcaça e comportamento ingestivo de novilhos terminados em confinamento alimentados com silagens dos híbridos de milho: Maximus VIP3, Defender VIP e Feroz VIP. O experimento teve duração de 112 dias, sendo quatro pesagens a cada 28 dias. As dietas experimentais foram formuladas e constituídas por silagem de milho e ração peletizada em proporção de 50:50, na base seca. Independentemente do híbrido utilizado, houve aumento conforme avanço na fase de terminação (9,15; 9,14; 9,35 e 9,59kg dia-1, na primeira, segunda, terceira e quarta pesagens, respectivamente). A distinção da silagem de milho determinou diferença no ganho de peso dos animais, com média final de 1,413kg para os animais tratados com Maximus VIP3, 1,375kg para os tratados com Defender VIP e 1,184 para aqueles alimentados com Feroz VIP. Os animais alimentados com silagem do híbrido Feroz VIP apresentaram maior eficiência de ganho de carcaça e foram mais ativos ao número de vezes em ir ao comedouro. Apesar dos três híbridos avaliados proporcionarem bons resultados relacionados ao desempenho animal, as características da carcaça não sofreram alterações; mesmo assim, recomenda-se o híbrido Maximus VIP3 por sua superioridade bromatológica.(AU)

Enhanced NMR relaxation of fluids confined to porous media: A proposed theory and experimental tests.

We propose a theory to account for the NMR relaxation of water protons in situations in which the fluid is confined to porous structures exhibiting a scarce distribution of paramagnetic centers on their surface. Though much of what is stated and assumed concerns the response of water, the model has sufficiently general features to be able to explain proton relaxation of other polar fluids under similar conditions. One of the main results of the paper is to show that the local anisotropy introduced by the dominant dipolar coupling in the relaxation rates of active surface elements induces a measurable dependence on sample orientation in the overall relaxation rates of the saturating fluid provided its confining structure is not statistically isotropic. Measurements of T_{1} proton relaxation on water saturating microcapillary tubes are performed to reveal the effect.

Coffea arabica and C. canephora discrimination in roasted and ground coffee from reference material candidates by real-time PCR.

To produce specific desirable coffee blends, Coffea arabica and C. canephora are mixed each other, in some cases to suit consumer preference, but in others to reduce production costs. In this scenario, the aim of this work was to evaluate standard candidate reference materials (RMc) for analysis of different blends of roasted and ground coffee. For this purpose, we analyzed different percentages of C. arabica and C. canephora (100:0; 50:50; 25:75; and 0:100, respectively). These RMc samples were developed in a previous study with green coffee beans submitted to medium roasting. In this work, coffee species differentiation (C. arabica and C. canephora) was analyzed by real-time PCR, using specific primers previously developed, called ARA primers. The RMc material with 100% C. canephora did not present amplification, in contrast with the samples containing C. arabica, which all presented amplification. These results indicate the specificity of ARA primers for C. arabica and that the detection system assay can be used as a promising molecular tool to identify and quantify percentages of C. arabica in different coffee blends.

A Promising Antiprion Trimethoxychalcone Binds to the Globular Domain of the Cellular Prion Protein and Changes Its Cellular Location.

The search for antiprion compounds has been encouraged by the fact that transmissible spongiform encephalopathies (TSEs) share molecular mechanisms with more prevalent neurodegenerative pathologies, such as Parkinson's and Alzheimer's diseases. Cellular prion protein (PrPC) conversion into protease-resistant forms (protease-resistant PrP [PrPRes] or the scrapie form of PrP [PrPSc]) is a critical step in the development of TSEs and is thus one of the main targets in the screening for antiprion compounds. In this work, three trimethoxychalcones (compounds J1, J8, and J20) and one oxadiazole (compound Y17), previously identified in vitro to be potential antiprion compounds, were evaluated through different approaches in order to gain inferences about their mechanisms of action. None of them changed PrPC mRNA levels in N2a cells, as shown by reverse transcription-quantitative real-time PCR. Among them, J8 and Y17 were effective in real-time quaking-induced conversion reactions using rodent recombinant PrP (rPrP) from residues 23 to 231 (rPrP23-231) as the substrate and PrPSc seeds from hamster and human brain. However, when rPrP from residues 90 to 231 (rPrP90-231), which lacks the N-terminal domain, was used as the substrate, only J8 remained effective, indicating that this region is important for Y17 activity, while J8 seems to interact with the PrPC globular domain. J8 also reduced the fibrillation of mouse rPrP23-231 seeded with in vitro-produced fibrils. Furthermore, most of the compounds decreased the amount of PrPC on the N2a cell surface by trapping this protein in the endoplasmic reticulum. On the basis of these results, we hypothesize that J8, a nontoxic compound previously shown to be a promising antiprion agent, may act by different mechanisms, since its efficacy is attributable not only to PrP conversion inhibition but also to a reduction of the PrPC content on the cell surface.

How the site degree influences quantum probability on inhomogeneous substrates.

We investigate the effect of the node degree and energy E on the electronic wave function for regular and irregular structures, namely, regular lattices, disordered percolation clusters, and complex networks. We evaluate the dependency of the quantum probability for each site on its degree. For a class of biregular structures formed by two disjoint subsets of sites sharing the same degree, the probability P_{k}(E) of finding the electron on any site with k neighbors is independent of E≠0, a consequence of an exact analytical result that we prove for any bipartite lattice. For more general nonbipartite structures, P_{k}(E) may depend on E as illustrated by an exact evaluation of a one-dimensional semiregular lattice: P_{k}(E) is large for small values of E when k is also small, and its maximum values shift towards large values of |E| with increasing k. Numerical evaluations of P_{k}(E) for two different types of percolation clusters and the Apollonian network suggest that this observed feature might be generally valid.

Pediatric laryngeal carcinoma in a heterozygous carrier of Fanconi anemia.

A case of invasive, keratinizing squamous cell carcinoma of the larynx in an 8-year-old female treated with laryngectomy is presented. Perinatal exposure to human papilloma virus and constitutional heterozygosity for a FANCC mutation were identified, though FANCC heterozygosity is not known to be cancer predisposing. An additional tumor-associated mutation in NOTCH1 was also identified potentially contributing to oncogenesis. This case illustrates an exceedingly rare type of cancer in the pediatric population and discusses diagnostic workup, evaluation of risk factors for head and neck cancer, and treatment options.

Exercise and the multidisciplinary holistic approach to adolescent dysautonomia.

AIM: To determine whether an eight-week strength training programme as part of a multidisciplinary approach would minimise symptoms and improve quality of life in patients with dysautonomia. METHODS: Adolescents referred to a tertiary-level cardiology service from May 2014-December 2015 with symptoms of dysautonomia were eligible. Participants completed an exercise test and a quality of life (QoL) questionnaire (PedsQL) prior to the intervention. Participants were asked to complete exercises five times per week. After eight weeks, participants returned for follow-up testing. Parents completed a proxy report of their child's QoL at both time points. RESULTS: A total of 17 participants completed the study protocol with an adherence rate of up to 50%. Post-intervention, QoL scores improved across all levels in the participants [total 65.2 (50.4-74.7) vs 48.9 (37.5-63.0); p = 0.006; psychosocial 65.8 (56.1-74.6) vs 50.0 (41.7-65.8); p = 0.010; physical 62.5 (37.5-76.6) vs 43.8 (25-68.5); p = 0.007] and their parent proxy reports [total 63.5 (48.7-81.3) vs 50.0 (39.3-63.0); p = 0.004; psychosocial 62.1 (52.1-81.3) vs 50.0 (39.6-59.2); p = 0.001; physical 62.5 (51.6-80.0) vs 50.0 (27.5-70.3); p = 0.003]. Treadmill time also improved (9.1 vs 8.0 minutes; p = 0.005). CONCLUSION: Following an eight-week strength training programme, dysautonomia patients report a significant improvement in both their quality of life and endurance time.

Seasonal study of concentration of heavy metals in waters from lower São Francisco River basin, Brazil / Estudo sazonal das concentrações de metais pesados em águas da bacia do submédio rio São Francisco, Brasil

Abstract In this study we determined the concentration of metals (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) in the water lower São Francisco River basin, to evaluate the influence of urbanization and industrialization on environmental changes in the water resource. All samples were analyzed using the IUPAC adapted method and processed in an atomic absorption spectrophotometer. The sampling stations located near the industrial areas were influenced by industrialization because they presented higher concentrations of Cd, Cr, Ni and Cu. The other sampled locations showed changes with regard the trace elements probably originating in the soil, like Fe, Zn and Pb. There was a gradual increase in the concentrations of metals, in general, in the period of highest rainfall of the hydrographic network. Overall, except for Zn and Mn, the trace elements exceeded the maximum allowed value established by national legislation (CONAMA). Lower São Francisco River basin has suffered interference from urbanization and industrialization, so awareness programs should be developed so as to control and lessen future problems.

Resumo Neste trabalho foi determinada a concentração dos metais (Cd, Cr, Cu, Fe, Mn, Ni, Pb e Zn) na água do submédio Rio São Francisco para avaliar a influência da urbanização e da industrialização nas modificações ambientais do recurso hídrico. Todas as amostras foram analisadas usando o método IUPAC adaptado e processados em um espectrofotômetro de absorção atômica. As estações de amostragem localizadas próximas às áreas industriais sofreram influência da industrialização por apresentarem concentrações mais elevadas de Cd, Cr, Ni e Cu. Os demais locais amostrados apresentaram modificações com relação aos elementos traços de provável origem sedimentar como Fe, Zn e Pb. Houve aumento gradativo nas concentrações dos metais, de forma geral, no período de maior pluviosidade da rede hidrográfica. Em geral, com exceção do Zn e Mn, os elementos traços ultrapassaram o valor máximo permitido, estabelecido pela legislação nacional (CONAMA). O submédio Rio São Francisco tem sofrido interferência da urbanização e industrialização, por isso, é preciso que, programas de conscientização sejam estabelecidos, para controlar e amenizar problemas futuros.

Analysis of worldwide sequence mutations in Zika virus proteins E, NS1, NS3 and NS5 from a structural point of view.

Zika virus (ZIKV) is an emergent arbovirus that has attracted attention in the last year as a possible causative agent of congenital malformation; it shows a remarkably increased microcephaly risk during otherwise healthy pregnancies. We present here an analysis of all ZIKV sequences available in Genbank up to April 2016, studying the mutations in the whole polyprotein and their possible structural implications for the proteins E, NS1, NS3 and NS5. This study suggests that microcephaly is not a consequence of any particular amino acid substitution but, conceivably, is a feature of ZIKV itself. Moreover, the structural analysis of ZIKV proteins, together with the mutational landscape of ZIKV and a structure-sequence comparison with other flaviviruses, allows the suggestion of regions that could be exploited as anti-ZIKV targets, including some allosteric sites found in the NS3 and NS5 proteins of DENV.