92 research outputs found

    The activity of laurel essential oil (crude and fractions) in the control of adult bovine ticks and larvae

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    Ectoparasites cause direct and indirect losses to farmers, affecting the production of meat and milk and increasing the production costs due to the acquisition of acaricides to maintain cattle health. The financial losses caused by Rhipicephalus (Boophilus) microplus, which is the main livestock ectoparasite in Brazil, reach approximately US$ 3 billion annually. The aim of this study was to evaluate the acaricidal effect of the crude essential oil (EO) and EO’s fractions (FR) obtained from Laurus nobilis L. (Lauraceae) leaves on Rhipicephalus (Boophilus) microplus. Eight fractions were obtained, wherein five major compounds were identified (sabinene, α-terpinyl acetate, 1,8-cineole, linalool, and α-terpineol). The acaricidal activity of these FR was tested by the larval packet test. The EO was tested by the adult immersion test, and, at concentrations of 200, 100 and 50 ”L/mL, the oil caused mortality of engorged females, egg mass reduction, and hatching inhibition. The fractions with α-terpineol and sabinene, as the major compounds, were the most active larvicides (LC50=0.13 ”L/mL, LC99=0.51 ”L/mL; and LC50=0.20 ”L/mL, LC99=0.56 ”L/mL, respectively). This assessment also indicated that fractionation was important since most of the fractions obtained were more active than the EO. Furthermore, this is the first report of laurel EO and its fractions employed in the control of cattle ticks. Thereby, new prospects for the use of this essential oil or its chromatographic fractions in products applied for cattle tick control can be opened up. However, studies in other stages of development of cattle ticks for the active fractions, and studies under field conditions, the effect on non-target organisms and residual effect on the environment are still needed to evaluate the acaricidal activity of EO and its active fractions

    Evaluation of the process of reabilitation of a stretch of Riparian forest in Itapemirim river watershed - ES

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    Este estudo foi realizado em uma ĂĄrea de floresta ciliar em processo de recuperação mediante reabilitação.A ĂĄrea de estudo estĂĄ localizada na sub-bacia hidrogrĂĄfica do rio Itapemirim, no MunicĂ­pio de Alegre, ES, Brasil.A ocupação e uso do solo antes da revegetação eram de pastagem com Brachiaria sp. A revegetação da ĂĄreafoi feita em 1997, com espĂ©cies autĂłctones e alĂłctones arbĂłreas, em arranjo de distribuição aleatĂłrio, em umaĂĄrea de 1,2 ha. Para a realização dos estudos foram feitos inventĂĄrios florestais nos perĂ­odos de 2004/2005e 2005/2006, sendo medidos os indivĂ­duos de hĂĄbito arbustivo e arbĂłreo com circunferĂȘncia Ă  altura do peito(CAP) > 5 cm e suas alturas totais. As espĂ©cies encontradas na ĂĄrea foram identificadas e classificadas de acordocom seus grupos ecolĂłgicos, sĂ­ndromes de dispersĂŁo e presença silvestre, sendo calculados os parĂąmetros florĂ­sticos,a estrutura vertical e a dinĂąmica estrutural desse povoamento. O objetivo do trabalho foi avaliar o desenvolvimentodo povoamento implantado para subsidiar prĂĄticas silviculturais quanto Ă  seleção e implantação de espĂ©cies pararevegetação de ĂĄreas de floresta ciliar degradadas, em condiçÔes semelhantes. Os resultados demonstraram quefoi implantado um povoamento florestal com grande diversidade de espĂ©cies e a estratificação em classes dealtura foi Ă  semelhança de povoamentos heterogĂȘneos naturais. As espĂ©cies identificadas como edificadoras darevegetação da ĂĄrea estudada foram: Anadenanthera colubrina, Caesalpinia leyostachia, Acacia auriculiformis,Acacia mangium, Handroanthus serratifolius, Inga edulis, Joannesia princeps, Pterogyne nitens, Enterelobiumcontortisiliquum, Tabernaemontana hystrix e Anthocephalus indicus. A distribuição em classes de tamanho dacomunidade implantada ocorre em forma de "J" reverso, havendo a predominĂąncia de indivĂ­duos pioneiros emtodas as classes de CAP. A dinĂąmica da estrutura horizontal apontou que, para o sucesso, continuidade e desenvolvimentoda recuperação da ĂĄrea, seja monitorada a regeneração natural em relação Ă  sua presença e Ă  eficiĂȘncia dos fatoresbiĂłticos e abiĂłticos que nela interferem. A nĂŁo observĂąncia de indivĂ­duos arbustivos e arbĂłreos regenerados naturalmente,na classe de inclusĂŁo do estudo, indica a fragilidade inicial da ĂĄrea rumo Ă  sustentabilidade do sistema.The study was realized in an area of riparian forest in process by means of rehabilitation. Thestudy area is located in Rio Itapemirim, in Alegre city, Brazil. The occupation and use of the soil beforethe recovery were of pasture with Brachiaria sp. The recovery of this area was in 1997, with autochthonousand allochthonous species, in casually distribution arrangement, in an area of 1,2 ha. For this studies wasrealized forest inventories in the periods of 2004/2005 and 2005/2006, being measured the arboreal individualswith circumference at breast height (CBH) and total heights. The species found in the area were identifiedand classified in this ecological groups, dispersion syndromes and wild presence, it forms calculated thefloristic parameters, the vertical structure and the structural dynamics of this plantation. The objective ofthis work went evaluate the development of the plantation implanted to subsidize practical silviculture withrelationship to the selection and plantation of species for the revegetation of degraded areas of riparianforest, in similar conditions. The results of the studies demonstrated that a forest plantation was implantedwith great diversity of species and the bedding in height classes it went to the likeness of natural heterogeneous.The species identified as builders of the plantation of the studied area were: Anadenanthera colubrina, Caesalpinia leyostachia, Acacia auriculiformis, Acacia mangium, Handroanthus serratifolius, Inga edulis, Joannesia princeps,Pterogyne nitens, Enterelobium contortisiliquum, Tabernaemontana hystrix, and Anthocephalus indicus . Theimplanted community's distribution diametric happens in reverse J shape having the pioneer individuals'predominance in all the classes of CBH. The dynamics of the horizontal structure points that for the success,continuity and development of the recovery of the area, the natural regeneration be monitored in relationto its presence and efficiency of the biotic factors and abiotic those interfere in the same. The not tree individualsobservance in natural regeneration, in the class of inclusion of the study, indicate the initial fragility of thearea heading for sustentabilidade of the system

    The effects of male age on sperm analysis by motile sperm organelle morphology examination (MSOME)

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    <p>Abstract</p> <p>Background</p> <p>This study aimed to investigate the influence of age on sperm quality, as analysed by motile sperm organelle morphology examination (MSOME).</p> <p>Methods</p> <p>Semen samples were collected from 975 men undergoing evaluation or treatment for infertility. Sperm cells were evaluated at 8400× magnification using an inverted microscope equipped with Nomarski (differential interference contrast) optics. Two forms of spermatozoa were considered: normal spermatozoa and spermatozoa with large nuclear vacuoles (LNV, defined as vacuoles occupying > 50% of the sperm nuclear area). At least 200 spermatozoa per sample were evaluated, and the percentages of normal and LNV spermatozoa were determined. The subjects were divided into three groups according to age: Group I, less than or equal to 35 years; Group II, 36-40 years; and Group III, greater than or equal to 41 years.</p> <p>Results</p> <p>There was no difference in the percentages of normal sperm between the two younger (I and II) groups (<it>P ></it>0.05). The percentage of normal sperm in the older group (III) was significantly lower than that in the younger (I and II) groups (<it>P </it>< 0.05). There was no difference in the percentage of LNV spermatozoa between the younger (I and II) groups (<it>P ></it>0.05). The percentage of LNV spermatozoa was significantly higher in the older group (III) than in the younger (I and II) groups (<it>P </it>< 0.05). Regression analysis demonstrated a significant decrease in the incidence of normal sperm with increasing age (<it>P </it>< 0.05; r = -0.10). However, there was a significant positive correlation between the percentage of spermatozoa with LNV and male age (<it>P </it>< 0.05, r = 0.10).</p> <p>Conclusion</p> <p>The results demonstrated a consistent decline in semen quality, as reflected by morphological evaluation by MSOME, with increased age. Considering the relationship between nuclear vacuoles and DNA damage, these age-related changes predict that increased paternal age should be associated with unsuccessful or abnormal pregnancy as a consequence of fertilisation with damaged spermatozoa. Given that sperm nuclear vacuoles can be evaluated more precisely at high magnification, these results support the routine use of MSOME for ICSI as a criterion for semen analysis.</p

    The thromboxane receptor antagonist NTP42 promotes beneficial adaptation and preserves cardiac function in experimental models of right heart overload

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    BackgroundPulmonary arterial hypertension (PAH) is a progressive disease characterized by increased pulmonary artery pressure leading to right ventricular (RV) failure. While current PAH therapies improve patient outlook, they show limited benefit in attenuating RV dysfunction. Recent investigations demonstrated that the thromboxane (TX) A2 receptor (TP) antagonist NTP42 attenuates experimental PAH across key hemodynamic parameters in the lungs and heart. This study aimed to validate the efficacy of NTP42:KVA4, a novel oral formulation of NTP42 in clinical development, in preclinical models of PAH while also, critically, investigating its direct effects on RV dysfunction.MethodsThe effects of NTP42:KVA4 were evaluated in the monocrotaline (MCT) and pulmonary artery banding (PAB) models of PAH and RV dysfunction, respectively, and when compared with leading standard-of-care (SOC) PAH drugs. In addition, the expression of the TP, the target for NTP42, was investigated in cardiac tissue from several other related disease models, and from subjects with PAH and dilated cardiomyopathy (DCM).ResultsIn the MCT-PAH model, NTP42:KVA4 alleviated disease-induced changes in cardiopulmonary hemodynamics, pulmonary vascular remodeling, inflammation, and fibrosis, to a similar or greater extent than the PAH SOCs tested. In the PAB model, NTP42:KVA4 improved RV geometries and contractility, normalized RV stiffness, and significantly increased RV ejection fraction. In both models, NTP42:KVA4 promoted beneficial RV adaptation, decreasing cellular hypertrophy, and increasing vascularization. Notably, elevated expression of the TP target was observed both in RV tissue from these and related disease models, and in clinical RV specimens of PAH and DCM.ConclusionThis study shows that, through antagonism of TP signaling, NTP42:KVA4 attenuates experimental PAH pathophysiology, not only alleviating pulmonary pathologies but also reducing RV remodeling, promoting beneficial hypertrophy, and improving cardiac function. The findings suggest a direct cardioprotective effect for NTP42:KVA4, and its potential to be a disease-modifying therapy in PAH and other cardiac conditions

    Pervasive gaps in Amazonian ecological research

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    Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio
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