Activity of Ricinus communis (Euphorbiaceae) against Spodoptera frugiperda (Lepidoptera: Noctuidae)

One of the most studied plant species with insecticidal properties is the castor bean Ricinus communis. However, its activity against Spodoptera frugiperda is unclear. Therefore, to determinate the insecticidal and insectistatic activities of methanol, hexane and ethyl acetate extracts of the seeds and leaves of R. communis, castor oil and ricinine were tested at different concentrations against S. frugiperda. This study demonstrated for the first time, that the castor oil and ricinine are active ingredients of R. communis that acts against S. frugiperda and that each of the seed extracts exhibited better insecticidal and insectistatic activity than the leaf extracts. The half maximum larvae viability concentration (LVC50) were 0.38 × 103 ppm for the ricinine, 0.75 × 103 ppm for a methanol extract ofseeds, 1.97 × 103 ppm for an ethyl acetate seed extract, 2.69×103 ppm for the castor oil, 4.83 × 103 ppm for a methanol extract of leaves, 5.07 × 103 ppm for an ethyl acetate extract of leaves, 9.95 × 103 ppm fora hexane extract of seeds and 10.01 × 103 ppm for a hexane extract of leaves

Biological activity of Ipomoea pauciflora Martens and Galeotti (Convolvulaceae) extracts and fractions on larvae of Spodoptera frugiperda J. E. Smith (Lepidoptera: Noctuidae)

Hexane, chloroform and methanol extracts of different parts of Ipomoea pauciflora were tested for their effects on the survival and development of Fall Armyworm (Spodoptera frugiperda), a Lepidoptera pest. For seven days, neonatal larvae (grown at 27 ± 2°C with a 16: 8 (L: D) h photoperiod) were exposed to different concentrations of crude I. pauciflora extracts (ranging from 0 to 4 mg/ml) that were incorporated into an artificial diet. Surviving larvae were weighed at days 6, 9 and 13 and were maintained until moths emerged. Eleven of the 18 crude extracts showed more than 30% larval mortality. The highest mortality was produced by hexane and chloroform extracts of seeds at 4 mg/ml(96.9 and 93.8%, respectively), with LC50 values of 1.85 mg/ml and 0.54 mg/ml, respectively. Fractions of both seed extracts were isolated by gravity column chromatography over silica gel and analyzed for their active compounds. Eight fractions of the hexane extract and six fractions of the chloroform extract from I. pauciflora seeds, exhibited larvicidal effects at 1 mg/ml (mortality from 33.3 to 88.9% and from 47.2 to 77%, respectively). Changes in larval weight were observed as compared with the control group. Phytochemical analysis through GC-MS and H1 NMR revealed the presence of fatty acids and aldehydes in the active fractions. These results indicate that the bioactive extracts from the seed of I. pauciflora can induce lethal toxicity in S. frugiperda larvae or affect the weight of the surviving larvae

Activity of Ricinus communis (Euphorbiaceae) against Spodoptera frugiperda (Lepidoptera: Noctuidae

One of the most studied plant species with insecticidal properties is the castor bean Ricinus communis. However, its activity against Spodoptera frugiperda is unclear. Therefore, to determinate the insecticidal and insectistatic activities of methanol, hexane and ethyl acetate extracts of the seeds and leaves of R. communis, castor oil and ricinine were tested at different concentrations against S. frugiperda. This study demonstrated for the first time, that the castor oil and ricinine are active ingredients of R. communis that acts against S. frugiperda and that each of the seed extracts exhibited better insecticidal and insectistatic activity than the leaf extracts. The half maximum larvae viability concentration (LVC 50 ) were 0.38 × 10 3 ppm for the ricinine, 0.75 × 10 3 ppm for a methanol extract of seeds, 1.97 × 10 3 ppm for an ethyl acetate seed extract, 2.69×10 3 ppm for the castor oil, 4.83 × 10 3 ppm for a methanol extract of leaves, 5.07 × 10 3 ppm for an ethyl acetate extract of leaves, 9.95 × 10 3 ppm for a hexane extract of seeds and 10.01 × 10 3 ppm for a hexane extract of leaves

Construction of 3D MR image-based computer models of pathologic hearts, augmented with histology and optical fluorescence imaging to characterize action potential propagation

International audienceCardiac computer models can help us understand and predict the propagation of excitation waves (i.e., action potential, AP) in healthy and pathologic hearts. Our broad aim is to develop accurate 3D MR image-based computer models of electrophysiology in large hearts (translatable to clinical applications) and to validate them experimentally. The specific goals of this paper were to match models with maps of the propagation of optical AP on the epicardial surface using large porcine hearts with scars, estimating several parameters relevant to macroscopic reaction-diffusion electrophysiological models. We used voltage-sensitive dyes to image AP in large porcine hearts with scars (3 specimens had chronic myocardial infarct, and 3 had radiofrequency RF acute scars). We first analyzed the main AP waves' characteristics: duration (APD) and propagation under controlled pacing locations and frequencies as recorded from 2D optical images. We further built 3D MR image-based computer models that have information derived from the optical measures, as well as morphologic MRI data (i.e., myocardial anatomy, fiber directions and scar definition). The scar morphology from MR images was validated against corresponding whole-mount histology. We also compared the measured 3D isochronal maps of depolarization to simulated isochrones (the latter replicating precisely the experimental conditions), performing model customization and 3D volumetric adjustments of the local conductivity. Our results demonstrated that mean APD in the border zone (BZ) of the infarct scars was reduced by ~13% (compared to ~318 ms measured in normal zone, NZ), but APD did not change significantly in the thin BZ of the ablation scars. A generic value for velocity ratio (1:2.7) in healthy myocardial tissue was derived from measured values of transverse and longitudinal conduction velocities relative to fibers direction (22cm/s and 60cm/s, respectively). The model customization and 3D volumetric adjustment reduced the differences between measurements and simulations; for example, from one pacing location, the adjustment reduced the absolute error in local depolarization times by a factor of 5 (i.e., from 58 ms to 11 ms) in the infarcted heart, and by a factor of 6 (i.e., from 60 ms to 9 ms) in the heart with the RF scar. Moreover, the sensitivity of adjusted conductivity maps to different pacing locations was tested, and the errors in activation times were found to be of approximately 10-12 ms independent of pacing location used to adjust model parameters, suggesting that any location can be used for model predictions

Percutaneous Coronary Intervention Versus Medical Therapy for Chronic Total Occlusion of Coronary Arteries:A Systematic Review and Meta-Analysis

PURPOSE OF REVIEW: Chronic total occlusion (CTO) of the coronary arteries is a significant clinical problem and has traditionally been treated by medical therapy or coronary artery bypass grafting. Recent studies have examined percutaneous coronary intervention (PCI) as an alternative option. RECENT FINDINGS: This systematic review and meta-analysis compared medical therapy to PCI for treating CTOs. PubMed and Embase were searched from their inception to March 2019 for studies that compared medical therapy and PCI for clinical outcomes in patients with CTOs. Quality of the included studies was assessed by Newcastle-Ottawa scale. The results were pooled by DerSimonian and Laird random- or fixed-effect models as appropriate. Heterogeneity between studies and publication bias was evaluated by I2 index and Egger's regression, respectively. Of the 703 entries screened, 17 studies were included in the final analysis. This comprised 11,493 participants. Compared to PCI, medical therapy including randomized and observational studies was significantly associated with higher risk of all-cause mortality (risk ratio (RR) 1.99, 95% CI 1.38-2.86), cardiac mortality (RR 2.36 (1.97-2.84)), and major adverse cardiac event (RR 1.25 (1.03-1.51)). However, no difference in the rate of myocardial infarction and repeat revascularization procedures was observed between the two groups. Univariate meta-regression demonstrated multiple covariates as independent moderating factors for myocardial infarction and repeat revascularization but not cardiac death and all-cause mortality. However, when only randomized studies were included, there was no difference in overall mortality or cardiac death. In CTO, when considering randomized and observational studies, medical therapy might be associated with a higher risk of mortality and myocardial infarction compared to PCI treatment

Photochemical Charge Separation in Poly(3-hexylthiophene) (P3HT) Films Observed with Surface Photovoltage Spectroscopy

Surface photovoltage spectroscopy (SPS) was used to probe photon induced charge separation in thin films of regioregular and regiorandom poly(3-hexylthiophene) (P3HT) as a function of excitation energy. Both positive and negative photovoltage signals were observed under sub-band-gap (<2.0 eV) and super-band-gap (>2.0 eV) excitation of the polymer. The dependence of the spectra on substrate work function, thermal annealing, film thickness, and illumination intensity was investigated, allowing the identification of interface, charge transfer (CT), and band-gap states in the amorphous and crystalline regions of the polymer films. The ability to probe these states in polymer films will aid the development and optimization of organic electronic devices such as photovoltaics (OPVs), light-emitting diodes (OLEDs), and field effect transistors (OFETs). The direction and size of the observed photovoltage features can be explained using the depleted semiconductor model. © 2013 American Chemical Society