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261.
Daniel F Kripke Caroline M Nievergelt Greg J Tranah Sarah S Murray Michael J McCarthy Katharine M Rex Neeta Parimi John R Kelsoe 《Journal of circadian rhythms》2011,9(1):1-7
Background
It has been reported that rs4446909, a single nucleotide polymorphism (SNP) in the promoter of acetylserotonin methyltransferase (ASMT), influences the expression of the ASMT enzyme. The common G allele is associated with lower ASMT activity, and therefore, diminishes conversion of N-acetylserotonin to melatonin. The G allele was associated with recurrent depressive disorder in a Polish group. ASMT might also affect bipolar relapse, given evidence that N-acetylserotonin might stimulate TRKB receptors, and TRKB may influence mood relapse in bipolar disorder. Additionally, arylalkylamine N-acetyltransferase (AANAT) polymorphisms have been reported associated with depression, perhaps through their influence upon N-acetylserotonin or melatonin synthesis.Results
To replicate and further explore these ideas, rs4446909 was genotyped in four research groups, as part of a panel of 610 SNPs surveyed by an Illumina Golden Gate assay. In 768 cases with delayed sleep phase disorder or matched controls, rs4446909 was indeed associated with the depressive symptoms on a self-report scale (P = 0.01, R2 = 0.007). However, there was no significant association of rs4446909 with self-reported depression in a sleep clinic patient group or with two groups of elderly men and women from multicenter studies, nor was the response to lithium treatment associated with rs4446909 in bipolar patients. No associations of two AANAT SNPs with depression were found.Conclusions
The evidence did not support a strong influence of rs4446909 upon mood, but the partial replication may be consistent with a modest effect. It is possible that larger or younger subject groups with improved phenotype ascertainment might demonstrate more persuasive replication. 相似文献262.
Terol J Mascarell R Fernandez-Pedrosa V Pérez-Alonso M 《Journal of agricultural and food chemistry》2002,50(5):963-969
Sequencing of the mitochondrial cytochrome b gene has been used to differentiate three tuna species: Thunnus albacares (yellowfin tuna), Thunnus obesus (bigeye tuna), and Katsuwonus pelamis (skipjack). A PCR amplified 528 bp fragment from 30 frozen samples and a 171 bp fragment from 26 canned samples of the three species were analyzed to determine the intraspecific variation and the positions with diagnostic value. Polymorphic sites between the species that did not present intraspecific variation were given a diagnostic value. The genetic distance between the sequences was calculated, and a phylogenetic tree was constructed, showing that the sequences belonging to the same species clustered together. The bootstrap test of confidence was used to determine the statistical validation of the species assignation, allowing for the first time a quantification of the certainty of the species assignation. The bootstrap values obtained from these results indicate that the sequencing of the cytochrome b fragments allows a correct species assignation with a probability > or =95%. 相似文献
263.
Growth and immune response of giant freshwater prawn Macrobrachium rosenbergii (De Man) postlarvae fed diets containing Chlorella vulgaris (Beijerinck) 下载免费PDF全文
Gian Carlo Maliwat Stephanie Velasquez Jan Lorie Robil Merab Chan Rex Ferdinand Traifalgar Melchor Tayamen Janice A Ragaza 《Aquaculture Research》2017,48(4):1666-1676
A 50‐day growth trial was conducted to evaluate the efficacy of Chlorella vulgaris (Beijerinck) as an ingredient in the diets of giant freshwater prawn Macrobrachium rosenbergii (De Man) postlarvae (PL30). Immune response (total haemocyte count and prophenoloxidase activity) was also assessed by subjecting postlarvae to a challenge test against Aeromonas hydrophila (Chester) for 14 days. Iso‐nitrogenous and iso‐lipidic test diets were prepared using a fishmeal‐based‐positive control diet (D0) and four basal diets with inclusion levels of 2% (D2), 4% (D4), 6% (D6) and 8% (D8) C. vulgaris. Postlarvae of M. rosenbergii were randomly stocked (mean initial body weight of 0.19 ± 0.02 g) in 30‐L tanks in three replicates per dietary treatment for evaluation of growth performance. Another set of postlarvae (mean initial body weight of 1.25 ± 0.02 g) was randomly distributed in 95‐L tanks in three replicates per dietary treatment for the assessment of immune response. Results showed that specific growth rate was significantly higher (P < 0.05) in postlarvae fed D4 and D6. Variations in values for carcass protein, lipid, moisture and ash were also evident. Postlarvae fed diets with Chlorella showed increased prophenol oxidase activity and total haemocyte counts. Moreover, survival rate after challenge with A. hydrophila was significantly increased (P < 0.05). Inclusion of C. vulgaris in diets enhanced immune response and resistance of M. rosenbergii postlarvae against A. hydrophila infection. 相似文献
264.
Herbert E. Quintero Alison Hutson Atra Chaimongkol Allen Davis Rex Dunham Asheber Abebe 《Journal of the World Aquaculture Society》2009,40(5):601-615
The interspecific hybridization of channel catfish, Ictalurus punctatus, females with blue catfish, I. furcatus, males has been identified as a method to further improve production; however, lack of spawning success has affected its commercial application. To facilitate our understanding of the interaction of brood stock nutrition and reproductive performance, we evaluated the interaction of feed quality and feeding frequency. Channel catfish females were classified into two genetic groups, namely, high and low spawning. The treatments were offered during the spring season 70–90 d prior to the start of the spawning season. Induced reproduction was performed using luteinizing hormone releasing hormone analog. Condition of the fish as well as reproductive performance using spawning success, egg production, egg size, and fertilization at 48 h were determined. Changing protein level of the diet from 32 to 42% did not influence spawning, fecundity, or fertilization, but affected egg size and biochemical composition of the eggs. Increasing the feeding frequency from three to six times per week negatively affected spawning in one of the two genetics groups, did not affect egg production and egg fertilization, but had a significant effect on egg size. Older fish performed better than younger fish in terms of spawning success and egg production. 相似文献
265.
266.
Aimone Porri Michael Betz Kathryn Seebruck Michael Knapp Philipp Johnen Matthias Witschel Raphael Aponte Rex Liebl Patrick J. Tranel Jens Lerchl 《Pest management science》2023,79(2):507-519
BACKGROUND
Target site resistance to herbicides that inhibit protoporphyrinogen IX oxidase (PPO; EC 1.3.3.4) has been described mainly in broadleaf weeds based on mutations in the gene designated protoporphyrinogen oxidase 2 (PPO2) and in one monocot weed species in protoporphyrinogen oxidase 1 (PPO1). To control PPO target site resistant weeds in future it is important to design new PPO-inhibiting herbicides that can control problematic weeds expressing mutant PPO enzymes. In this study, we assessed the efficacy of a new triazinone-type inhibitor, trifludimoxazin, to inhibit PPO2 enzymes carrying target site mutations in comparison with three widely used PPO-inhibiting herbicides.RESULTS
Mutated Amaranthus spp. PPO2 enzymes were expressed in Escherichia coli, purified and measured biochemically for activity and inhibition kinetics, and used for complementation experiments in an E. coli hemG mutant that lacks the corresponding microbial PPO gene function. In addition, we used ectopic expression in Arabidopsis and structural PPO protein modeling to support the enzyme inhibition study. The generated data strongly suggest that trifludimoxazin is a strong inhibitor both at the enzyme level and in transgenics Arabidopsis ectopically expressing PPO2 target site mutations.CONCLUSION
Trifludimoxazin is a potent PPO-inhibiting herbicide that inhibits various PPO2 enzymes carrying target site mutations and could be used as a chemical-based control strategy to mitigate the widespread occurrence of PPO target site resistance as well as weeds that have evolved resistance to other herbicide mode of actions. © 2022 BASF SE and The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. 相似文献267.
Ricardo Musule Enrique Alarcón-Gutiérrez Eric P. Houbron Guadalupe M. Bárcenas-Pazos M. del Rosario Pineda-López Zaira Domínguez Lázaro R. Sánchez-Velásquez 《Journal of Wood Science》2016,62(6):537-547
Tree adaptation to environment has been extensively studied. However, little is known about the variations in structure and chemical composition of lignocellulosic biomass (LB) in relation to altitudinal gradient. We wonder, are there significant variations in the LB in the wood across an altitudinal gradient? To answer this, we carried out a study of Abies religiosa. Wood samples were collected from 36 trees, grown between 3000 and 3500 masl, and then subjected to gravimetric and FTIR (Fourier Transform Infrared) spectroscopic analyses. The gravimetric results showed a proportion of 54.81 ± 2.20 % cellulose, 12.37 ± 1.33 % hemicellulose and 24.68 ± 1.16 % of insoluble lignin. Using the principal components analysis with analysis of variance (ANOVA), significant differences were found at 3100 and 3200 masl in two independent components related to both hemicellulose and lignin, through gravimetry as well as the spectroscopic bands assigned to the carbonyl groups of these polymers, respectively. However, the observed changes in chemical composition of LB did not follow a linear relationship with respect to the altitudinal gradient, which suggests that complex environmental interactions could also be playing an important role. Also, there were significant differences (p < 0.05) in two of the empirical indexes calculated from the FTIR analysis. 相似文献
268.
The antimicrobial and free radical scavenging activity of the ethanol extract and fractions of Gentianella nitida have been assessed. The most susceptible microorganisms were Candida albicans, Trichophyton mentagrophytes and Microsporum gypseum. The antifungal activity was concentrated in the 90% methanol and nonsoluble fractions, while the radical scavenging activity was stronger in the ethyl acetate and nonsoluble fractions. 相似文献
269.
Hugo Fernando López-Arévalo Sonia Gallina Rosario Landgrave Enrique Martínez-Meyer Lyssette E. Muñoz-Villers 《Biological conservation》2011,(5):1451-1463
Landscape-scale studies facilitate species diversity analysis according to environmental heterogeneity and human activity. This study was aimed at using local knowledge as a tool for testing predictive models’ validity for assessing the spatial distribution of medium-sized mammalian richness, identifying local patterns of species richness and evaluating local protected areas’ role in the conservation of mammals. Distribution maps were generated for historically recorded species using genetic algorithm for rule-set prediction (GARP). The landscape was reclassified as habitat, hospitable matrix and inhospitable matrix in the second scenario and a third scenario was generated limiting species distribution by using the home range. The local richness predicted by all scenarios varied from 1 to 32 species per cell while gamma diversity was 34. The 72 structured interviews led to recording 3–17 species (a total of 27). There have been no reports of nine wild species over the last 2 years. Currently protected areas cannot support viable populations of the species so recorded so shade coffee plantations must adopt conservation strategies. Historical inventories overestimate expected richness; however, combining GARP-generated models with the information obtained from local inhabitants and experts allows rapid regional evaluation of medium-sized mammalian richness and the identification of extinct species, declining populations and abundant species. 相似文献
270.
Martínez-Gil AM Garde-Cerdán T Martínez L Alonso GL Salinas MR 《Journal of agricultural and food chemistry》2011,59(7):3253-3263
Volatile compounds from a commercial aqueous oak extract application to white Verdejo grapevines at veraison have been studied. Treated grapes under two types of formulation (25% and 100%) have been analyzed at the optimum maturation time, and winemaking was then subsequently carried out. The volatile compounds were analyzed by stir bar sorptive extraction-gas chromatography-mass spectrometry. The results suggest that after the grapevine treatments, grapes store the volatiles in the form of nonvolatile precursors, and some of the volatiles are released during the winemaking process, especially six months after the alcoholic fermentation. The sensory analysis shows that wines maintain the typical aroma properties of Verdejo wines at the end of fermentation; but after six months, the wine color is greener and more astringent, and, in terms of aroma, it has wooden notes as if the wine has been aged in oak barrels. 相似文献