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991.
Benzimidazolylterpenes, possessing a 2,7-dimethyloctane skeleton showed IGR-activity on pupae of Tenebrio molitor L in laboratory tests: N-(7-methoxy-2,7-dimethyl-2-octenyl)benzimidazole showed the greatest activity. 相似文献
992.
Ekaterina D. Obluchinskaya Olga N. Pozharitskaya Elena V. Flisyuk Alexander N. Shikov 《Marine drugs》2021,19(11)
Fucoidan is a polysaccharide found in brown alga with glorious potential for pharmacological activities, among which its anti-inflammatory properties have gained meaningful attention. Due to several advantages of formulations for topical application, this study aimed to develop and optimize a fucoidan-based cream formulation and to investigate its anti-inflammatory potential after topical application in vivo. Fucoidan from Fucus vesiculosus L. was used. The cream base consisting of olive oil and Kolliphor RH40 was optimized followed by in vitro agar diffusion and drug release studies. The fucoidan-based cream with 13% Kolliphor P 407, 1% Transcutol P, and 5% PEG400 showed good spreadability, washability, and colloidal stability, and it did not irritate the skin. The kinetics of fucoidan release from the optimized cream exhibited the best fit to the Korsmeyer–Peppas and Higuchi models with R2 > 0.99. Fucoidan release was controlled by drug diffusion and anomalous transport provided by the optimized cream base. The formulation was stable and provided high fucoidan release after storage for 1 year. Topical application of the fucoidan-based cream dose-dependently inhibited carrageenan-induced edema and ameliorated mechanical allodynia in rats. The efficacy of the fucoidan-based cream at a high dose was comparable with the efficacy of diclofenac gel. The fucoidan-based cream could be considered a promising anti-inflammatory formulation. 相似文献
993.
Physiological stress responses to captivity in early developmental stages of the wedge sole Dicologoglossa cuneata (Moreau)
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Marcelino Herrera Ana Rodiles Beatriz Sánchez Juan M López Elena de La Roca 《Aquaculture Research》2016,47(3):732-740
The stress responses in early growth stages of the wedge sole have been studied to determine whether the high cortisol levels described in juvenile fish are present from early developmental stages. Whole‐body cortisol, glucose and lactate contents, as well as biometric parameters in wedge sole larvae were measured at three different stocking densities. Stocking density affected growth‐related variables significantly, and larvae in lower stocking densities grew faster. Survival did not significantly differ among treatments. At hatching, the whole‐body cortisol concentration was 0.33 ± 0.01 ng g?1 and varied significantly from 0 to 30 days after hatching (DAH) for each stocking density, though values remained stable for the remaining time in the low‐stocking density group. These hormone levels rose significantly (5.17 ± 2.43 to 22.10 ± 4.95 ng g?1) at the end of the experiment, depending directly on the stocking density. Glucose and lactate‐body concentrations did not vary among treatments. We conclude that the stress responses of wedge sole larvae are detectable from 45 DAH and that stocking density already can be a stressor at that age. As described for juvenile stage, cortisol content values in wedge sole larvae under non‐stressful conditions are one of the highest among those reported in the literature. The captivity conditions could be responsible for this apparently stressful situation, though those values also could be normal in wild specimens. 相似文献
994.
The use of peat as a growing media in forestry nurseries is decreasing due to high costs and environmental considerations.
Furthermore, diverse waste products are being used as organic amendments in certain soils before afforestation. In this study,
combinations of both of these resources are considered and seven different materials were used to make mixtures of growing
media used for maritime pine tree production in a forestry nursery. Pine bark, Sphagnum peat and paper mill sludge were mixed with sewage sludge, sewage activated sludge, municipal solid waste with activated composted
sludge and inorganic fertilizer to fill containers where pine seeds were sown. Germination was monitored 30–50 days after
sowing. Needle samples from each treatment were taken and physical parameters (height, stem diameter, aerial dry weight, main
root dry weight, total dry weight) were measured along with several morphological attributes. Foliar nutrient content was
also determined (N, P, K, Ca, Mg, Fe, Cu, Mn and Zn). The highest values for germination percentage were obtained for 75%
pine bark + fertilizer and for sewage sludge treatments. Seedlings grown in paper mill sludge + activated sewage sludge + peat
and in paper mill sludge + activated sewage sludge + pine bark mixtures presented the best physical parameter values. Municipal
solid waste and composted sludge were the most useful amendments for morphological attributes. After linking morphological
indexes and foliar nutrient content, the best Dickson Quality Index values correspond with higher values of N, Ca, Mg, Cu
and Zn and lower values of P, K, Fe and Mn.
Resumen El uso de turba en viveros forestales como sustrato de cultivo está decreciendo debido a su elevado coste y consideraciones medioambientales. Por otro lado, distintos residuos están siendo utilizados como enmiendas orgánicas sobre ciertos suelos previa reforestación. En este estudio, se considera una combinación de ambos factores y siete diferentes materiales fueron usados para hacer mezclas de sustrato de cultivo para la producción de pino marítimo en un vivero forestal. Corteza de pino, turba de esfagno y residuo de pasta de papel fueron mezclados con lodo de depuradora, lodo activado, residuos sólidos urbanos + lodo compostado y fertilizante inorgánico y utilizados para rellenar bandejas donde fue realizada la siembra. La germinación fue monitorizada 30–50 días después de la siembra. Se tomaron muestras de acículas de cada tratamiento y se analizaron parámetros físicos (altura, diámetro del tallo, peso seco parte aérea, peso seco de la raíz principal, peso seco total) además de distintos atributos morfológicos. El contenido foliar en nutrientes también se determinó (N, P, K, Ca, Mg, Fe, Cu, Mn and Zn). Los valores más elevados del porcentaje de germinación se obtuvieron para las mezclas: 75% corteza de pino + fertilizante y las enmiendas con lodo. El crecimiento de las plántulas presentó los mejores valores de los parámetro físicos para: residuo de pasta de papel + lodo activado + turba y para residuo pasta de papel + lodo activado + corteza de pino. La mezcla de residuos sólidos urbanos + lodo compostado proporcionó los mejores valores en relación a los atributos morfológicos. Relacionando los índices morfológicos con el contenido foliar en nutrientes se vió que los mejores valores para el Indice de Calidad de Dickson correspondieron con los valores más altos de N, Ca, Mg, Cu y Zn y los más bajos de P, K, Fe and Mn en el tejido foliar.相似文献
995.
Characterization of Streptomyces spp. Isolated from the Sea Surface Microlayer in the Trondheim Fjord, Norway
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Sigrid Hakvg Espen Fjrvik Kjell D. Josefsen Elena Ian Trond E. Ellingsen Sergey B. Zotchev 《Marine drugs》2008,6(4):620-635
The water surface microlayer is still poorly explored, although it has been shown to contain a high density of metabolically active bacteria, often called bacterioneuston. Actinomycetes from the surface microlayer in the Trondheim fjord, Norway, have been isolated and characterized. A total of 217 isolates from two separate samples morphologically resembling the genus Streptomyces have been further investigated in this study. Antimicrobial assays showed that about 80% of the isolates exhibited antagonistic activity against non-filamentous fungus, Gram-negative, and Gram-positive bacteria. Based on the macroscopic analyses and inhibition patterns from the antimicrobial assays, the sub-grouping of isolates was performed. Partial 16S rDNAs from the candidates from each subgroup were sequenced and phylogenetic analysis performed. 7 isolates with identical 16S rDNA sequences were further studied for the presence of PKS type I genes. Sequencing and phylogenetic analysis of the PKS gene fragments revealed that horizontal gene transfer between closely related species might have taken place. Identification of unique PKS genes in these isolates implies that de-replication can not be performed based solely on the 16S rDNA sequences. The results obtained in this study suggest that streptomycetes from the neuston population may be an interesting source for discovery of new antimicrobial agents. 相似文献
996.
Lothar Frese Lorenz Bülow Marion Nachtigall María Luisa Rubio Teso Maria Cristina Duarte Elena Rey José María Iriondo Alegría 《Euphytica》2017,213(8):187
The genetic diversity of Patellifolia patellaris has been investigated to generate information required for the organisation of a systematic genetic resources conservation action combining the best elements of the ex situ and in situ conservation concept. To this end, ten occurrences of the species were sampled on the Iberian Peninsula in Portugal and Spain. A total of 271 individuals was analysed using 24 microsatellite markers. The factorial analysis separated the material into two occurrences from Portugal, two occurrences sampled east of Gibraltar and six occurrences from the eastern Spanish coast. The pairwise genetic distance between occurrences and the complementary compositional differentiation among occurrences were calculated. The genetic distance values were used to construct an Unweighted Pair Group Method with Arithmetic Mean tree, which can be separated into four equidistant clusters. Two clusters are located in Portugal and two further clusters in Spain. The factorial analysis as well as the genetic distance and differentiation analysis indicate that the two occurrences from Portugal are clearly genetically different from the Spanish group of occurrences. Both occurrences have low population sizes and are therefore highly endangered. In situ conservation actions are urgently required for both occurrences. Further investigations are needed to organise better informed conservation actions for P. patellaris, namely to study genetic relationships between occurrences on the Spanish mainland and occurrences distributed on the Canary Islands, Madeira and Cape Verde Islands as well as in Morocco. 相似文献
997.
Alexandra V. Amosova Lyudmila V. Zemtsova Olga Yu. Yurkevich Elena N. Zhidkova Tomasz Książczyk Natalia G. Shostak Anatoly A. Muravlev Anna M. Artemyeva Tatiana E. Samatadze Svyatoslav A. Zoshchuk Olga V. Muravenko 《Euphytica》2017,213(9):217
Resynthesized Brassica napus L. is an important source for broadening genetic diversity and producing lines with desired characteristics. It is also a fine model to study the processes of genomic reorganizations in recently formed polyploids. We firstly performed molecular cytogenetic characterization of newly resynthesized rapeseed (B. rapa ssp. narinosa × B. oleracea ssp. capitata) and its parental species, and also examined genomic changes in hybrids of the succeeding generations grown under pressure of selection of yellow-seeded progeny. For karyotype studies, FISH/GISH with 45S, 5S rDNA, C genome specific BoB014O06 BAC clone and genomic DNA of parental B. rapa was performed. Synthetic S0–S2 hybrids had common rapeseed karyotypes (2n = 38) including 14 loci of 45S rDNA sites and 10 loci of 5S rDNA. Progeny selection led to gradual deletion of C genome chromosomes in hybrid karyotypes. So, in karyotypes of S6 and S7 hybrids, the chromosome number was reduced to 2n = 20–22, and only chromosomes of A genome bearing 10–13 loci of 45S rDNA and 8–10 loci of 5S rDNA, variations in chromosome number, chromosome rearrangements as well as examples of trisomy and monosomy were revealed. Our findings indicate an enhanced genome instability in resynthesized rapeseed lines developed under the pressure of selection which might lead to chromosome rearrangements or/and deletions and even elimination of the whole parental genome in hybrids in succeeding generations. The approach can be useful for the development of rapeseed lines with trisomy, chromosome addition/substitution lines important for genetics and plant breeding. 相似文献
998.
The cabbage root fly Delia radicum L. (Diptera: Anthomyiidae) is one of the major pests of many Brassica crops in the temperate areas of Europe and North America. At present, turnip (B. rapa ssp. rapa L.) varieties resistant to the pest does not exist. With the aim to fill this gap, a no-choice tolerance test of 56 accessions among turnips, turnip tops and turnip greens was performed under controlled conditions by introducing D. radicum eggs. Plant survival, leaf and root conditions, pupae number and weight significantly varied among plant accessions. Ten putatively resistant and ten susceptible accessions (control group) were selected from this first screening, transplanted in the field and exposed to natural infestation to detect antibiosis and antixenosis mechanisms. Both in the laboratory and in the field, pupae number significantly varied within accessions and between resistant and susceptible group, although pupal weight did not, indicating the absence of antibiosis effect on this early stage. In the field, the number of galleries was significantly lower in the resistant group in comparison with the control. Resistant accessions had smaller size, and a smaller, white and mostly buried root. Within the resistant and susceptible accessions, larger plants harboured more pupae, however purple roots were those most preferred, and the hosted pupae weighed most. Three accessions from the resistant group (MBGBR0178, MBGBR0570 and MBGBR0371) stand out for resistance to D. radicum possibly through antixenosis mechanisms. 相似文献
999.
1000.
Macrophage lipid accumulation induced by low density lipoproteins (LDL) plays a pivotal role in atherosclerotic plaque development. Previous work showed that Ocimum basilicum extract, used as hypocholesterolemic agent by traditional medicine in Morocco, has hypolipidemic activity in rat acute hyperlipimidemia. This study investigated the effects of ethanolic extract of O. basilicum on lipid accumulation in human macrophages. As modification of LDL increase atherogenicity of the particles we evaluated the effects of the extract on LDL oxidation. The extract caused a dose-related increase of LDL-resistance to Cu(2+)-induced oxidation. Furthermore, at the dose of 60 microg/ml, significantly decreases the accumulation of macrophage lipid droplets induced by modified LDL evaluated as by red-oil staining. Cholesterol esterification and triacylglycerol synthesis in the cells were not affected. Macrophage treatment with 60 microg/ml, but not 20 microg/ml, of the extract reduced newly synthesized unesterified cholesterol by about 60% and decreased scavenger receptors activity by about 20-30%, evaluated by the internalization of cholesterol carried by [(3)H]CE-aggregated-LDL. The results suggest that O. basilicum ethanolic extract has the capability to reduce foam cell formation through the reduction of cholesterol synthesis and the modulation of the activity of surface scavenger receptors. 相似文献