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291.
292.
Yossi Tal Ari Ayalon Agnesa Sharaev Zoya Kazir Vera Brekhman Tamar Lotan 《Marine drugs》2014,12(2):734-745
Transdermal delivery is an attractive option for drug delivery. Nevertheless, the skin is a tough barrier and only a limited number of drugs can be delivered through it. The most difficult to deliver are hydrophilic drugs. The stinging mechanism of the cnidarians is a sophisticated injection system consisting of microcapsular nematocysts, which utilize built-in high osmotic pressures to inject a submicron tubule that penetrates and delivers their contents to the prey. Here we show, for the first time, that the nematocysts of the starlet sea anemone Nematostella vectensis can be isolated and incorporated into a topical formulation for continuous drug delivery. We demonstrate quantitative delivery of nicotinamide and lidocaine hydrochloride as a function of microcapsular dose or drug exposure. We also show how the released submicron tubules can be exploited as a skin penetration enhancer prior to and independently of drug application. The microcapsules are non-irritant and may offer an attractive alternative for hydrophilic transdermal drug delivery. 相似文献
293.
Dayrit FM Buenafe OE Chainani ET de Vera IM 《Journal of agricultural and food chemistry》2008,56(14):5765-5769
Phosphorus-31 nuclear magnetic resonance spectroscopy ( (31)P NMR) was used to differentiate virgin coconut oil (VCO) from refined, bleached, deodorized coconut oil (RCO). Monoglycerides (MGs), diglycerides (DGs), sterols, and free fatty acids (FFAs) in VCO and RCO were converted into dioxaphospholane derivatives and analyzed by (31)P NMR. On the average, 1-MG was found to be higher in VCO (0.027%) than RCO (0.019%). 2-MG was not detected in any of the samples down to a detection limit of 0.014%. On the average, total DGs were lower in VCO (1.55%) than RCO (4.10%). When plotted in terms of the ratio [1,2-DG/total DGs] versus total DGs, VCO and RCO samples grouped separately. Total sterols were higher in VCO (0.096%) compared with RCO (0.032%), and the FFA content was 8 times higher in VCO than RCO (0.127% vs 0.015%). FFA determination by (31)P NMR and titration gave comparable results. Principal components analysis shows that the 1,2-DG, 1,3-DG, and FFAs are the most important parameters for differentiating VCO from RCO. 相似文献
294.
Body condition and stage of seasonal anestrus interact to determine the ovulatory response after male biostimulation in anovulatory Criollo × Nubian goats
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Hector R. Vera‐Avila Jorge Urrutia‐Morales Mario A. Espinosa‐Martinez Hector G. Gamez‐Vazquez Hector Jimenez‐Severiano Eugenio Villagomez‐Amezcua 《Animal Science Journal》2017,88(6):841-846
The effect of goat nutritional condition on the response to biostimulation with sexually active males during different stages of anestrus was determined. Fifty‐eight Criollo × Nubian females on high and low body mass index (BMI) diets were used. Each BMI group was divided into two for biostimulation with sexually active males during May (mid‐anestrus) or July (transition period). Ovulatory responses to biostimulation were characterized from serum progesterone, as well as the delay for response (first and second ovulations followed by a normal length luteal phase, O‐WNLP). The percentage of goats showing one O‐WNLP was greater in the high BMI group than in the low BMI group and greater during the transition period than in the mid‐anestrus. However, the interaction between factors revealed that the difference between BMI groups was only significant in the transition period and the difference between stages was only significant in goats with high BMI. Occurrence of a second O‐WNLP tended to be greater in the high BMI group than in the low BMI group. Response delay was shorter in the transition period than in mid‐anestrus. In conclusion, female nutritional status interacting with the stage of anestrus determined the ovulatory response to male biostimulation in crossbred Criollo goats. 相似文献
295.
Administration of exogenous hormones in ovulatory and embryonic response in Pelibuey sheep
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A García‐Salas C Cortez‐Romero J Salazar‐Ortiz J Arroyo‐Ledezma VM Ruíz‐Vera H Vaquera‐Huerta J Gallegos‐Sánchez 《Reproduction in domestic animals》2017,52(3):446-451
The objective of this study was to evaluate the effect of two sources of commercial porcine pituitary‐derived follicle‐stimulating hormone (pFSH) and pFSH—porcine Luteinizing Hormone (pLH), including equine chorionic gonadotropin (eCG), in ovulatory and embryonic response in Pelibuey sheep. Twenty‐four Pelibuey sheep were used and were assigned randomly to four treatments (n = 6): (T1; 200 mg pFSH‐Folltropin®); (T2; 200 mg pFSH + 300 UI eCG‐Folligon®); (T3; 250 UI pFSH/pLH‐Pluset®) and (T4; 250 UI pFSH/pLH + 300 UI eCG). The interval of hours from withdrawal of the device to the beginning of oestrus (BO) was lower (p < .05) in sheep treated with eCG (T2 = 8.0 ± 1.4 and T4 = 10.0 ± 2.8) than in those without eCG (T1 = 12.6 ± 0.6 and T3 = 20.6 ± 2.4). The ovulatory rate (OR) was higher (p < .05) in T1 = 15.5 ± 2.8 and T2 = 15.6 ± 1.4, compared to T3 = 8.1 ± 3.2 and T4 = 11.8 ± 2.8; a significant difference was not shown between them (T1 vs. T2 and T3 vs. T4) when including eCG. The number of non‐fertilized oocytes (NFO) was lower (p ? .05) in T1 = 0.8 ± 0.4 and T3 = 1.8 ± 1.8, compared to those that included eCG (T2 = 6.3 ± 2.4 and T4 = 2.1 ± 1.2). The number of transferable embryos (TE) was higher (p < .05) when FSH was applied (T1 = 5.8 ± 1.1), compared with (T2 = 2.6 ± 1.1, T3 = 2.3 ± 1.4 and T4 = 2.8 ± 1.5). The commercial treatments (pFSH or pFSH‐pLH) in combination with eCG did not improve OR, NFO and TE. However, the exclusive pFSH (Folltropin) treatment presented a higher OR, lower number of NFO and higher number of TE. 相似文献
296.
Gerbert Sylvestre Dossa Rolando Torres Amelia Henry Ricardo Oliva Edgar Maiss Casiana Vera Cruz Kerstin Wydra 《European journal of plant pathology / European Foundation for Plant Pathology》2017,147(1):115-127
Plant response to one type of stress can be affected by simultaneous exposure to a second stress, for example when abiotic and biotic stresses occur together. Ten rice genotypes comprising those with bacterial blight (BB) resistance (R) genes, drought quantitative trait loci (QTLs) plus a BB R gene, and BB susceptible genotypes, were subjected to mild and moderate drought stress and plants were inoculated with two Xoo strains (PXO99 and PXO145) to simulate the challenges rice crops face under simultaneous stress of drought and BB. Plant height and dry shoot biomass were significantly reduced by drought stress treatments. The BB disease lesion lengths varied according to rice genotypes and PXO99 Xoo multiplication and spread in planta was higher compared to that of PXO145, which generally decreased under mild drought stress. Rice genotype IRBB7 (Xa7) showed less Xoo spread and a reduced Xoo multiplication under drought stress compared to the well-watered control with PXO145. In contrast, in genotypes with a different BB R gene and/or drought QTLs [IRBB4 (Xa4), IR87705–6-9-B (Xa4 + qDYT 2.2 ), IR87707–445-B-B-B (Xa4 + qDYT 2.2 + qDYT 4.1 ) and IR87707–446-B-B-B (Xa4 + qDYT 2.2 + qDYT 4.1 )], Xoo multiplication and spread in planta was higher with drought stress. This study has shown that drought stress affected rice response to the BB pathogen and the response varied according to the rice genotype. It is concluded that evaluating rice varieties under combined abiotic and biotic stresses will be the best strategy to determine biotic stress resistance durability under climate change. 相似文献
297.
Rebekah Alcock Alan McCubbin Vera Camões-Costa Ricardo J.S. Costa 《The Forestry Chronicle》2018,29(4):508-520
To assess the impact of rationed versus full estimated energy provisions on markers of physiological strain in response to a simulated 250 km multistage ultramarathon (MSUM), on two separate occasions, the ultraendurance runner performed a laboratory simulated MSUM, with rationed (RP: 3303±75 kcal?day-1) and full (FP: 7156±359 kcal?day-1) provisions. Total daily energy expenditure was determined using dual-method indirect calorimetry. Resting metabolic rate, iDXA, and body water were measured at baseline, day 3, and post-MSUM. Blood, urine, and feces were collected, and mood state was measured, d 1 to 5 (before and after running) to determine various physiological strain indices. Heart rate, RPE, thermal comfort, gastrointestinal symptoms, and non-protein oxidation rates were measured every 30 min during running. Data were analyzed using single-subject design analysis and interpreted using Cohen's effect size. Energy expenditure was lower on RP (6943±145 kcal?day-1) than FP (7486±143 kcal?day-1) (Cohen's δ=-3.1). More pronounced exertional strain (RPE δ=1.2, thermal conform δ=0.6, rectal temperature δ=1.0, and plasma cortisol concentration δ=1.7) was observed on RP as the MSUM progressed. Total carbohydrate and fat oxidation during running decreased (0.76 vs. 1.82 g?min-1; δ=-3.9) and increased (0.91 vs. 0.54 g?min-1; δ=3.7), respectively, more profoundly on RP as the MSUM progressed. Gastrointestinal symptoms were modestly lower in RP (δ=-0.26). Exercise-induced leukocytosis, cytokinaemia, and neutrophil responses were higher on RP. Iron status markers were trivial. Higher mood disturbance and fatigue were reported on RP. The ultraendurance runner presented greater physiological and psychophysiological disturbances, in response to a laboratory simulated MSUM, on rationed energy provisions, despite the lighter pack-weight. 相似文献
298.
Liz Ota John Herbohn Steve Harrison Nestor Gregorio Vera Lex Engel 《Agroforestry Systems》2018,92(6):1597-1609
Systematic mapping studies provide a snapshot of the literature based on systematic literature searches. In this systematic mapping study, the original research that links reforestation and livelihoods in the tropics was mapped and analysed to identify the trends, biases and gaps in the literature. In total, 339 papers from 92 journals were identified. Agroforestry Systems was the journal in which articles were most frequently published, and Cameroon and Indonesia the most frequently studied countries. The greatest number of authors came from the USA, and authors were most commonly affiliated with ICRAF. A limited collaboration between research groups in the tropical regions was identified. Anthropology and Social Sciences were the most frequent areas of research, especially in Africa. Latin America had more technical studies and more publications discussing payment for environmental services than the other regions. Based on the temporal analysis of the main terms in abstracts of the publications included, it was found that agriculture-related terms and terms related to the human component in the landscape were consistently prevalent in the literature relating reforestation and livelihoods throughout time. Agroforestry systems were especially important in small-scale reforestation and livelihoods. Trends, biases and gaps were discussed. Broader cooperation between tropical regions and between clusters of authors would be beneficial for research and practice. 相似文献
299.
Pedro Sánchez-Gómez Juan F. Jiménez Jose Luis Cánovas Juan Bautista Vera Isabell Hensen Miloud Aouissat 《Annals of Forest Science》2018,75(3):75
Key message
The genetic structure of Juniperus phoenicea in the Mediterranean Basin is inferred using amplified fragment length polymorphism markers (AFLP) markers. As other Mediterranean conifers, J. phoenicea populations show moderate levels of genetic diversity and interpopulational differentiation. The pattern of distribution of genetic diversity seems highly influenced by the climatic fluctuations which occurred in the Pleistocene.Context
It has been stated that the genetic structure of Mediterranean conifers is mediated by the historical climatic changes and the geological rearrangements which occurred in the Mediterranean Basin. J. phoenicea provides an excellent example to test how its genetic structure is influenced by these events.Aims
In this work, we study the amount and distribution of genetic diversity of J. phoenicea complex, in order to evaluate its taxonomic status and to reveal underlying phylogeographic patterns.Methods
The molecular diversity was analyzed for 805 individuals from 46 populations throughout its distribution range using AFLP markers. Principal coordinate analysis, analysis of molecular variance (AMOVA), and Bayesian-based analysis were applied to examine the population structure.Results
AFLP markers revealed moderate levels of intrapopulation genetic diversity, pairwise genetic differentiation, and a clear pattern of isolation by distance. Bayesian analysis of population structure showed five clusters related to the taxonomic status of J. phoenicea and J. turbinata, and a geographic pattern of genetic structure in J. turbinata.Conclusion
All the analysis separate J. phoenicea from J. turbinata. For J. turbinata, up to four groups can be distinguished from a phylogeographic point of view. The genetic structure of J. turbinata seems highly influenced by climatic and geologic fluctuations occurring since the Oligocene.300.
Anne C. RICHER-de-FORGES Dominique ARROUAYS Laura POGGIO Songchao CHEN Marine LACOSTE Budiman MINASNY Zamir LIBOHOVA Pierre ROUDIER Vera L. MULDER Herv NDLEC Guillaume MARTELET Blandine LEMERCIER Philippe LAGACHERIE Hocine BOURENNANE 《土壤圈》2023,33(5):731-743
Digital maps of soil properties are now widely available. End-users now can access several digital soil mapping (DSM) products of soil properties, produced using different models, calibration/training data, and covariates at various spatial scales from global to local. Therefore, there is an urgent need to provide easy-to-understand tools to communicate map uncertainty and help end-users assess the reliability of DSM products for use at local scales. In this study, we used a large amount of hand-feel soil texture (HFST) data to assess the performance of various published DSM products on the prediction of soil particle size distribution in Central France. We tested four DSM products for soil texture prediction developed at various scales (global, continental, national, and regional) by comparing their predictions with approximately 3 200 HFST observations realized on a 1:50 000 soil survey conducted after release of these DSM products. We used both visual comparisons and quantitative indicators to match the DSM predictions and HFST observations. The comparison between the low-cost HFST observations and DSM predictions clearly showed the applicability of various DSM products, with the prediction accuracy increasing from global to regional predictions. This simple evaluation can determine which products can be used at the local scale and if more accurate DSM products are required. 相似文献