Quinclorac controls crabgrass (Digitaria spp.) post-emergence in cool- and warm-season turfgrass. A rate response study revealed that two Mississippi smooth crabgrass (Digitaria ischaemum) species (MSU1 and MSU2) are resistant to quinclorac. Following that, field experiments were carried out to evaluate programmatic approaches to control one of these populations. Despite prior study on quinclorac-resistant weeds, to date, quinclorac-resistant smooth crabgrass and its mechanism of resistance have only been reported once in California. The mechanism of resistance of MSU1 and MSU2 relative to susceptible (SMT) was then investigated. The SMT biotype accumulated three times more cyanide than the resistant populations. Glutathione-S-transferase (GST) activity was evaluated as a possible contributor to non-target site resistance. The GST activity was elevated in the MSU1 and MSU2 populations. These findings suggest a non-target site–based mechanism of resistance involving the accumulation of cyanide. Further research is needed to investigate potential target-site mechanisms of resistance.

In the Western United States, the Great Basin is a geographic feature that is home to a variety of unique species, including Great Basin bristlecone pine (Pinus longaeva, PILO). P. longaeva is well known for the age of some of the trees, some of which are over 4000 years old. In this study 17 microsatellite markers (simple sequence repeat, SSR) are identified and used to genotype a selection of 480 individuals spread across 24 PILO populations and 60 individuals divided equally between 2 outgroup species, Pinus aristata and Pinus flexilis. One population of PILO, HMW, shows more genetic similarity with P. aristata, and is included with outgroup species in the analysis. The population structure of PILO is examined and found to be weakly related to the geographic distance between populations. The population statistics Fst, Gst, Rst, Dest and an AMOVA analysis suggest that there is a substantial amount of admixture at the individual level, similar to some other species of pines. Phylogenetic trees computed using the neighbor-joining method based on the average population genetic distance and based on individual genetic distance support the population structure results and show further evidence that most of the species variation is concentrated at the individual level, rather than inside of or between species. It is possible that gene flow is still occurring, or that gene flow has occurred recently enough that the separated populations have not yet diverged from each other in a measurable way.

No description available.

No description available.

No description available.

Os carrapatos Rhipicephalus (Boophilus) microplus e Haemaphysalis longicornis são ectoparasitas hematófagos que infestam bovinos. O uso de vacinas anticarrapato tem mostrado ser uma estratégia alternativa promissora para o controle desses parasitos. As glutationa-S-transferases (GSTs) pertencem a uma família de enzimas multifuncionais presentes em organismos animais e vegetais, e, entre suas funções, pode-se destacar o transporte intracelular, a participação em processos digestivos, a síntese de prostaglandinas, a detoxificação de substâncias tóxicas e a proteção contra o estresse oxidativo. Em trabalhos anteriores, verificou-se em camundongos que a GST de H. longicornis (rGST-Hl) é mais imunogênica que a GST de R. microplus (rGST-Bm). O objetivo do presente estudo foi investigar a proteção cruzada conferida pela imunização de bovinos com a rGST-Hl frente a uma infestação de R. microplus. Por Western blot, verificou-se que os bovinos vacinados com a rGST-Hl apresentaram um aumento nos níveis de anticorpos anti-rGST-Hl, os quais foram capazes de reconhecer a GST-Bm nativa de extratos de larva, ovário e glândula salivar. Posteriormente, os bovinos foram infestados com 20.000 larvas de R. microplus. O percentual de proteção conferido foi calculado em função da variação entre os grupos tratados e controle, em relação ao número e peso de carrapatos que terminaram a alimentação, a capacidade de postura e a fertilidade dos ovos. O grupo dos bovinos vacinados com rGST-Hl mostrou uma redução de 53% e 52% no número e no peso de teleóginas, respectivamente. A postura de ovos e a eclodibilidade apresentaram uma redução no grupo vacinado de 0,6% e 8%, respectivamente. A eficácia total contra a infestação de R. microplus foi de 57%, quando comparado ao grupo controle. / The ticks Rhipicephalus (Boophilus) microplus and Haemaphysalis longicornis are hematophagous ectoparasites that infest bovines. Vaccine has been considered one of the most promising methods for the control of these parasites. Glutathione Stransferases (GSTs) enzymes are present in animal and vegetal organisms and are important in intracellular transport, digestive process, synthesis of prostaglandins, detoxification and protection against oxidative stress. In a previous study with mice we showed that H. longicornis GST (rGST-Hl) is more immunogenic than R. microplus GST (rGST-Bm). The objective of the present study was to investigate the crossprotection against R. microplus infestation in bovine vaccinated with rGST-Hl. By Western blot, the immunized bovines showed an increase in antibodies anti-rGST-Hl. The native GST-Bm in larvae, ovary and salivary gland were recognized by sera of bovines immunized with rGST-Hl, indicating that the antibodies induced by rGST-Hl immunization recognize native R. microplus GSTs. The bovines were challenged with 20,000 larvae of R. microplus. Protection was calculated by variation in number and weight of fully engorged ticks, egg laying capacity and egg fertility. The bovines vaccinated with rGST-Hl showed a reduction of 53% and 52% in number and weight of engorged ticks, respectively. Egg laying capacity and egg fertility of ticks from vaccinated bovines were respectively 0.6% and 8% lower, as compared to ticks from control animals. The overall efficacy ratio against R. microplus was 57.03%, as compared with the control group.

L'évaluation de l'impact des polluants dans l'environnement est une des préoccupations majeures qui s'inscrit dans la Directive Européenne Cadre Eau 2000. Les réglementations préconisées ont notamment pour objectif de parvenir au bon état chimique et écologique des masses d'eau. Dans ce contexte, notre étude a consisté à développer une approche multibiomarqueur sur des juvéniles de poisson afin d'évaluer les effets biologiques de la pollution chimique en milieu littoral. Des paramètres moléculaires de détoxification (EROD, GST) et une enzyme antioxydante (CAT) ont été utilisés en tant que "système d'alarme " susceptibles de détecter une perturbation avant l'apparition de signes pathologiques irréversibles. En parallèle, différents biomarqueurs physiologiques (croissance somatique et récente, rapport ARN/ADN, indices morphométrique et lipidique) ont été analysés en considérant que ceux-ci pourraient révéler les dommages induit par les polluants sur l'état de santé des juvéniles. La sensibilité et la pertinence des biomarqueurs moléculaires et physiologiques ont été testés expérimentalement sur des juvéniles : i) de bar exposés à une pollution aigüe de pétrole, ii) de bar et de turbot soumis à des mélanges de contaminants en concentrations environnementales en conditions contrôlée et semi-contrôlée (" caging "). Nos résultats montrent la capacité de l'EROD, et à un degré moindre de la GST, à détecter une exposition courte (2 et 4 jours) des organismes au pétrole et à refléter ses effets délétères sur leur état de santé. Cette relation entre biomarqueurs moléculaires et physiologiques a par contre été plus difficilement établie dans un contexte de pollution multiple. Les indices de croissance et de condition utilisés se sont avérés plus sensibles aux différents niveaux de contamination analysés (métaux et HAPs). Leur utilisation a permis d'évaluer la condition affaiblie des organismes mis en cage en milieu portuaire pendant 38 jours. Cette expérience de " caging " s'est révélée concluante, notamment pour les juvéniles de bar, sur lesquels aucun stress physiologique de la mise en cage n'a été détecté dans la station de référence. Les effets délétères des contaminants chimiques sur l'état de santé des juvéniles de turbot ont également été observés en condition contrôlée après exposition de 21 jours aux mêmes sédiments portuaires et à un sédiment estuarien. En complément de ces expériences, une étude de terrain a été réalisée sur des juvéniles de flet prélevés dans des estuaires le long de la côte française et belge. Une diminution des indices morphométrique et lipidique des juvéniles de flet, issu des trois estuaires anthropisés, a été observée en relation avec des bioconcentrations en métaux plus élevées que l'estuaire de référence. Les résultats issus de ces différentes études montrent la potentialité des indices de croissance et de condition à révéler les effets biologiques des contaminants chimiques sur les juvéniles de poissons marins. Cependant, leur spécificité vis à vis des polluants étant plus faible que les paramètres de détoxification, leur utilisation peut être limitée. Ces travaux montrent ainsi le besoin d'utiliser des biomarqueurs à différents niveaux d'organisation biologique dans les programmes de biosurveillance.

Cancer is the second leading cause of death after cardiovascular diseases in the world. Many of the chemical carcinogens need metabolic activation that catalyzed by cytochrome P450 and Phase II enzymes in order to exert their genotoxic and carcinogenic effects. Hence one possible mechanism is that phenolic compounds may alter anticarcinogenic effects is through an interaction with these enzymes either by the inhibition or activation of certain forms, leading to a reduced production of the ultimate carcinogen. Therefore anti-carcinogen activity of tannic acid, a hydrolyzable plant polyphenol, has a crucial importance to prevent conversion of pro-carcinogens to their carcinogenic form. Tannic acid is produced from secondary metabolism of plants and is found in edible vegetables, fruits and nuts, especially tea, cocoa, coffee and wine. In the present work, modulation of rabbit liver and kidney microsomal P450 dependent aniline 4-hydroxylase, N-nitrosodimethylamine N-demethylase and p-nitrophenol hydroxylase activities and cytosolic phase II enzymes / glutathione S-transferase (GST), NAD(P)H:quinone oxidoreductase:1 (NQO1) were studied in the presence of tannic acid at concentrations ranging from 0.5 &micro / M to 150 &micro / M in the reaction medium. The results obtained in this study were shown that tannic acid significantly inhibited the activities of p-nitrophenol hydroxylase, aniline 4-hydroxylase, NDMA N-demethylase, glutathione S-transferase, NAD(P)H:quinine oxidoreductase 1. Tannic acid was found to be the most potent inhibitor of cytosolic glutathione S-transferase with IC50 of 0.33 &micro / M and the least potent inhibitor of microsomal aniline 4-hydroxylase.with IC50 of 60.26 &micro / M. Effect of tannic acid on enzyme activities was further studied for both mode and type of inhibition. For this purpose various concentrations of the substrate were examined at various tannic acid concentrations. Lineweaver-Burk and Dixon plots were then generated from the resulting data sets. The Km value and inhibition constants (KI) were determined from double reciprocal and Dixon plot of the enzyme activity versus substrate and inhibitor concentration, respectively. Tannic acid was shown to be a noncompetitive inhibitor for liver cytosolic GST, NQO1 and microsomal aniline 4- hydroxylase enzymes with KI of 0.3 &micro / M, 41 &micro / M and 54.7 &micro / M, respectively. On the other hand, in kidney tissues, tannic acid was an uncompetitive inhibitor of cytosolic GST, while it was noncompetitive inhibitor for cytosolic NQO1 with a KI of 12.6 &micro / M. These results indicate that tannic acid may modulate cytochrome P450 dependent and Phase II enzymes and influence the metabolic activation of xenobiotics mediated by these enzymes.

Os carrapatos Rhipicephalus (Boophilus) microplus e Haemaphysalis longicornis são ectoparasitas hematófagos que infestam bovinos. O uso de vacinas anticarrapato tem mostrado ser uma estratégia alternativa promissora para o controle desses parasitos. As glutationa-S-transferases (GSTs) pertencem a uma família de enzimas multifuncionais presentes em organismos animais e vegetais, e, entre suas funções, pode-se destacar o transporte intracelular, a participação em processos digestivos, a síntese de prostaglandinas, a detoxificação de substâncias tóxicas e a proteção contra o estresse oxidativo. Em trabalhos anteriores, verificou-se em camundongos que a GST de H. longicornis (rGST-Hl) é mais imunogênica que a GST de R. microplus (rGST-Bm). O objetivo do presente estudo foi investigar a proteção cruzada conferida pela imunização de bovinos com a rGST-Hl frente a uma infestação de R. microplus. Por Western blot, verificou-se que os bovinos vacinados com a rGST-Hl apresentaram um aumento nos níveis de anticorpos anti-rGST-Hl, os quais foram capazes de reconhecer a GST-Bm nativa de extratos de larva, ovário e glândula salivar. Posteriormente, os bovinos foram infestados com 20.000 larvas de R. microplus. O percentual de proteção conferido foi calculado em função da variação entre os grupos tratados e controle, em relação ao número e peso de carrapatos que terminaram a alimentação, a capacidade de postura e a fertilidade dos ovos. O grupo dos bovinos vacinados com rGST-Hl mostrou uma redução de 53% e 52% no número e no peso de teleóginas, respectivamente. A postura de ovos e a eclodibilidade apresentaram uma redução no grupo vacinado de 0,6% e 8%, respectivamente. A eficácia total contra a infestação de R. microplus foi de 57%, quando comparado ao grupo controle. / The ticks Rhipicephalus (Boophilus) microplus and Haemaphysalis longicornis are hematophagous ectoparasites that infest bovines. Vaccine has been considered one of the most promising methods for the control of these parasites. Glutathione Stransferases (GSTs) enzymes are present in animal and vegetal organisms and are important in intracellular transport, digestive process, synthesis of prostaglandins, detoxification and protection against oxidative stress. In a previous study with mice we showed that H. longicornis GST (rGST-Hl) is more immunogenic than R. microplus GST (rGST-Bm). The objective of the present study was to investigate the crossprotection against R. microplus infestation in bovine vaccinated with rGST-Hl. By Western blot, the immunized bovines showed an increase in antibodies anti-rGST-Hl. The native GST-Bm in larvae, ovary and salivary gland were recognized by sera of bovines immunized with rGST-Hl, indicating that the antibodies induced by rGST-Hl immunization recognize native R. microplus GSTs. The bovines were challenged with 20,000 larvae of R. microplus. Protection was calculated by variation in number and weight of fully engorged ticks, egg laying capacity and egg fertility. The bovines vaccinated with rGST-Hl showed a reduction of 53% and 52% in number and weight of engorged ticks, respectively. Egg laying capacity and egg fertility of ticks from vaccinated bovines were respectively 0.6% and 8% lower, as compared to ticks from control animals. The overall efficacy ratio against R. microplus was 57.03%, as compared with the control group.

Os carrapatos Rhipicephalus (Boophilus) microplus e Haemaphysalis longicornis são ectoparasitas hematófagos que infestam bovinos. O uso de vacinas anticarrapato tem mostrado ser uma estratégia alternativa promissora para o controle desses parasitos. As glutationa-S-transferases (GSTs) pertencem a uma família de enzimas multifuncionais presentes em organismos animais e vegetais, e, entre suas funções, pode-se destacar o transporte intracelular, a participação em processos digestivos, a síntese de prostaglandinas, a detoxificação de substâncias tóxicas e a proteção contra o estresse oxidativo. Em trabalhos anteriores, verificou-se em camundongos que a GST de H. longicornis (rGST-Hl) é mais imunogênica que a GST de R. microplus (rGST-Bm). O objetivo do presente estudo foi investigar a proteção cruzada conferida pela imunização de bovinos com a rGST-Hl frente a uma infestação de R. microplus. Por Western blot, verificou-se que os bovinos vacinados com a rGST-Hl apresentaram um aumento nos níveis de anticorpos anti-rGST-Hl, os quais foram capazes de reconhecer a GST-Bm nativa de extratos de larva, ovário e glândula salivar. Posteriormente, os bovinos foram infestados com 20.000 larvas de R. microplus. O percentual de proteção conferido foi calculado em função da variação entre os grupos tratados e controle, em relação ao número e peso de carrapatos que terminaram a alimentação, a capacidade de postura e a fertilidade dos ovos. O grupo dos bovinos vacinados com rGST-Hl mostrou uma redução de 53% e 52% no número e no peso de teleóginas, respectivamente. A postura de ovos e a eclodibilidade apresentaram uma redução no grupo vacinado de 0,6% e 8%, respectivamente. A eficácia total contra a infestação de R. microplus foi de 57%, quando comparado ao grupo controle. / The ticks Rhipicephalus (Boophilus) microplus and Haemaphysalis longicornis are hematophagous ectoparasites that infest bovines. Vaccine has been considered one of the most promising methods for the control of these parasites. Glutathione Stransferases (GSTs) enzymes are present in animal and vegetal organisms and are important in intracellular transport, digestive process, synthesis of prostaglandins, detoxification and protection against oxidative stress. In a previous study with mice we showed that H. longicornis GST (rGST-Hl) is more immunogenic than R. microplus GST (rGST-Bm). The objective of the present study was to investigate the crossprotection against R. microplus infestation in bovine vaccinated with rGST-Hl. By Western blot, the immunized bovines showed an increase in antibodies anti-rGST-Hl. The native GST-Bm in larvae, ovary and salivary gland were recognized by sera of bovines immunized with rGST-Hl, indicating that the antibodies induced by rGST-Hl immunization recognize native R. microplus GSTs. The bovines were challenged with 20,000 larvae of R. microplus. Protection was calculated by variation in number and weight of fully engorged ticks, egg laying capacity and egg fertility. The bovines vaccinated with rGST-Hl showed a reduction of 53% and 52% in number and weight of engorged ticks, respectively. Egg laying capacity and egg fertility of ticks from vaccinated bovines were respectively 0.6% and 8% lower, as compared to ticks from control animals. The overall efficacy ratio against R. microplus was 57.03%, as compared with the control group.