Atividade carrapaticida in vitro de nanoemulsão à base de óleo essencial de Ocotea elegans (Lauraceae) sobre larvas de Rhipicephalus (Boophilus) microplus.

Alternativas para controle do carrapato Rhipicephalus (Boophilus) microplus têm sido estudadas devido ao grande prejuízo econômico que este causa na pecuária. Em estudo fitoquímico prévio por CG/MS e RMN, identificaram-se sesquiterpenos (sesquirosefurano = 92,2% da composição relativa total) no óleo essencial (OE) das folhas de Ocotea elegans, possivelmente relacionados com seu potencial repelente sobre R. (B.) microplus

Marine substrate response from the analysis of seismic attributes in CHIRP sub-bottom profiles

O presente trabalho tem por objetivo apresentar uma avaliação da resposta dos atributos sísmicos (Amplitude Instantânea, Amplitude RMS, Energia e Frequência Instantânea) em diferentes tipos de substratos marinhos, correlacionando-os com características sedimentológicas das amostras coletadas. Foram analisados perfis sísmicos obtidos com um perfilador de subsuperfície com sinal do tipo CHIRP modelo SB-216S da marca EdgeTech, com frequência de trabalho de 2 e 16 kHz. O método se deu a partir da análise estatística não-paramétrica de Kruskal-Wallis foi aplicada para comparar o comportamento dos atributos com as diferentes classes dos grãos das amostras (subagrupadas segundo o grau de seleção) e com diferentes feições. Com base na análise dos resultados, foi possível distinguir dois grupos distintos nas amostras, o grupo SAMF (silte e areia muito fina) e o grupo AFMG (areia fina, areia média e areia grossa). Como conclusão, pode-se dizer que os atributos não foram capazes de distinguir entre as classes mais próximas dos grãos. Utilizando o coeficiente de Spearman foi verificado que o atributo "Amplitude Instantânea" mostrou-se mais eficiente em separar os dois conjuntos. Comparando sedimentos, gás e rocha, os atributos que utilizaram o atributo "amplitude" foram eficazes em separar os sedimentos do gás e da rocha, porém não os distinguiram entre as duas feições, visto que elas apresentaram amplitudes muito altas, mas semelhantes entre si. O atributo "Frequência Instantânea" mostrou-se eficaz na diferenciação entre sedimento, rocha e gás, o sedimento apresentou uma maior banda de frequência, a rocha uma faixa intermediária e o gás a menor delas.This paper presents an evaluation of the response of seismic reflection attributes in different types of marine substrate (rock, shallow gas, sediments) using seafloor samples for ground-truth statistical comparisons. The data analyzed include seismic reflection profiles collected using two CHIRP subbottom profilers (Edgetech Model 3100 SB-216S), with frequency ranging between 2 and 16 kHz, and a number (38) of sediment samples collected from the seafloor. The statistical method used to discriminate between different substratum responses was the non-parametric Kruskal-Wallis analysis, carried out in two steps: 1) comparison of Seismic Attributes between different marine substrates (unconsolidated sediments, rock and shallow gas); 2) comparison of Seismic Attributes between different sediment classes in seafloors characterized by unconsolidated sediments (subdivided according to sorting). These analyses suggest that amplitude-related attributes were effective in discriminating between sediment and gassy/rocky substratum, but did not differentiate between rocks and shallow gas. On the other hand, the Instantaneous Frequency attribute was effective in differentiating sediments, rocks and shallow gas, with sediment showing higher frequency range, rock an intermediate range, and shallow gas the lowest response. Regarding grain-size classes and sorting, statistical analysis discriminated between two distinct groups of samples, the SVFS (silt and very fine sand) and the SFMC (fine, medium and coarse sand) groups. Using a Spearman coefficient, it was found that the Instantaneous Amplitude was more efficient in distinguishing between the two groups. None of the attributes was able to distinguish between the closest grain size classes such as those of silt and very fine sand

Distinct mechanisms for diastolic dysfunction in diabetes mellitus and chronic pressure-overload

Chronic pressure-overload and diabetes mellitus are two frequent disorders affecting the heart. We aimed to characterize myocardial structural and functional changes induced by both conditions. Pressure-overload was established in Wistar-han male rats by supra-renal aortic banding. Six-weeks later, diabetes was induced by streptozotocin (65 mg/kg,ip), resulting in four groups: SHAM, banding (BA), diabetic (DM) and diabetic-banding (DB). Six-weeks later, pressure-volume loops were obtained and left ventricular samples were collected to evaluate alterations in insulin signalling pathways, extracellular matrix as well as myofilament function and phosphorylation. Pressure-overload increased cardiomyocyte diameter (BA 22.0 ± 0.4 μm, SHAM 18.2 ± 0.3 μm) and myofilament maximal force (BA 25.7 ± 3.6 kN/m(2), SHAM 18.6 ± 1.4 kN/m(2)), Ca(2+) sensitivity (BA 5.56 ± 0.02, SHAM 5.50 ± 0.02) as well as MyBP-C, Akt and Erk phosphorylation, while decreasing rate of force redevelopment (K (tr); BA 14.9 ± 1.1 s(-1), SHAM 25.2 ± 1.5 s(-1)). At the extracellular matrix level, fibrosis (BA 10.8 ± 0.9%, SHAM 5.3 ± 0.6%), pro-MMP-2 and MMP-9 activities increased and, in vivo, relaxation was impaired (τ; BA 14.0 ± 0.9 ms, SHAM 12.9 ± 0.4 ms). Diabetes increased cardiomyocyte diameter, fibrosis (DM 21.4 ± 0.4 μm, 13.9 ± 1.8%, DB 20.6 ± 0.4 μm, 13.8 ± 0.8%, respectively), myofilament Ca(2+)sensitivity (DM 5.57 ± 0.02, DB 5.57 ± 0.01), advanced glycation end-product deposition (DM 4.9 ± 0.6 score/mm(2), DB 5.1 ± 0.4 score/mm(2), SHAM 2.1 ± 0.3 score/mm(2)), and apoptosis, while decreasing K (tr) (DM 13.5 ± 1.9 s(-1), DB 15.2 ± 1.4 s(-1)), Akt phosphorylation and MMP-9/TIMP-1 and MMP-1/TIMP-1 ratios. Diabetic hearts were stiffer (higher end-diastolic-pressure: DM 7.0 ± 1.2 mmHg, DB 6.7 ± 0.7 mmHg, SHAM 5.3 ± 0.4 mmHg, steeper end-diastolic-pressure-volume relation: DM 0.59 ± 0.18, DB 0.83 ± 0.17, SHAM 0.41 ± 0.10), and hypo-contractile (decreased end-systolic-pressure-volume-relation). DB animals presented further pulmonary congestion (Lungs/body-weight: DB 5.23 ± 0.21 g/kg, SHAM 3.80 ± 0.14 g/kg) as this group combined overload-induced relaxation abnormalities and diabetes-induced stiffness. Diabetes mellitus and pressure overload led to distinct diastolic dysfunction phenotypes: while diabetes promoted myocardial stiffening, pressure overload impaired relaxation. The association of these damages accelerates the progression of diastolic heart failure progression in diabetic-banded animals

First report of the effect of Ocotea elegans essential oil on Rhipicephalus (Boophilus) microplus.

Rhipicephalus (Boophilus) microplus is responsible for reducing animal welfare, causing a drop in productive performance and transmitting hemoparasites. The main strategy of tick control is application of synthetic acaricides. However, parasite resistance to these compounds is a major concern. Therefore, the acaricidal and repellent in vitro effect of the Ocotea elegans essential oil on larvae and adult females of R. (B.) microplus were evaluated. The larval packet test (LPT), larval repellency test (RT) and adult immersion test (AIT) were performed. The essential oil was analyzed by gas chromatography (GC/FID) and the structure of the oil?s major constituent (92.2% sesquirosefuran) was elucidated by nuclear magnetic resonance. In the AIT, efficacy higher than 90% was detected from the concentration 25 mg/mL upward. In both LPTs performed after 48 h, only the 100 mg/mL concentration resulted in mortalities above 70%. On the other hand, the essential oil caused an average of 95.8% repellency from 0.78 to 100 mg/mL. The LC50 in the two LPT (48 h) tests were 59.68 and 25.59 mg/mL, respectively. The LC50 and LC90 in the AIT were 4.96 and 17.37 mg/mL, and in the RT they were 0.04 and 1.24 mg/mL respectively. We conclude that the essential oil of O. elegans leaves has a significant acaricidal effect on engorged females and on larval repellency of R. (B.) microplus ticks, and can be a promising alternative for the control of this ectoparasite.Made available in DSpace on 2019-01-16T23:38:26Z (GMT). No. of bitstreams: 1 Figueiredoetal2018EssentialoilOcotea.pdf: 575681 bytes, checksum: 32866849269b4d067aa1f0100820d1fc (MD5) Previous issue date: 2018-06-29bitstream/item/179297/1/Figueiredo-et-al-2018-Essential-oil-Ocotea.pd