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101.
102.
Helen K. Woodfield Amaury Cazenave-Gassiot Richard P. Haslam Irina A. Guschina Markus R. Wenk John L. Harwood 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2018,1863(3):339-348
With dwindling available agricultural land, concurrent with increased demand for oil, there is much current interest in raising oil crop productivity. We have been addressing this issue by studying the regulation of oil accumulation in oilseed rape (Brassica napus L). As part of this research we have carried out a detailed lipidomic analysis of developing seeds.The molecular species distribution in individual lipid classes revealed quite distinct patterns and showed where metabolic connections were important. As the seeds developed, the molecular species distributions changed, especially in the period of early (20 days after flowering, DAF) to mid phase (27DAF) of oil accumulation. The patterns of molecular species of diacylglycerol, phosphatidylcholine and acyl-CoAs were used to predict the possible relative contributions of diacylglycerol acyltransferase (DGAT) and phospholipid:diacylglycerol acyltransferase to triacylglycerol production. Our calculations suggest that DGAT may hold a more important role in influencing the molecular composition of TAG. Enzyme selectivity had an important influence on the final molecular species patterns.Our data contribute significantly to our understanding of lipid accumulation in the world's third most important oil crop. 相似文献
103.
Angel Bernal-Treviño Ana María González-Amaro Verónica Méndez González Amaury Pozos-Guillen 《Revista iberoamericana de micología》2018,35(2):78-82
Background
Microbiological identification in endodontic infections has focused mainly on bacteria without giving much attention to yeasts, which, due to their virulence factors, can affect the outcomes of root canal treatment.Aims
To determine the frequency of Candida in anaerobic conditions in root canals with primary and persistent endodontic infection, as well as to evaluate a microbiological sampling method using aspiration compared to the traditional absorption method with paper points.Methods
Fifty microbiological samples were obtained from teeth of 47 patients requiring endodontic treatments, due to either primary or persistent infections. Two microbiological sampling methods were used: an aspiration method, and the traditional paper point absorption method. In each of these methods, two types of medium were used (M1-M4). Samples were cultured under anaerobic conditions until reaching 0.5 McFarland turbidity, and then inoculated on Sabouraud dextrose, as well as on anaerobic enriched blood agar plates. Macroscopic and microscopic observations of the colonies were performed. The germ-tube test, growth on CHROMagar, and biochemical identification were performed on the isolated yeasts.Results
Fungal infection was found in 18 (36%) samples out of the 50 teeth evaluated. In the 18 samples positive for fungal infection, 15 out of 36 (41.6%) teeth were taken from a primary infection, and 3 out of 14 (21.4%) from a persistent infection. The aspiration method using Sabouraud dextrose medium recovered a greater diversity of species.Conclusions
Yeasts frequency was higher in teeth with primary infections compared to teeth with persistent infections. The predominant yeast species was Candida albicans. The aspirating sampling method was more efficient in the recovery of Candida isolates than the traditional absorption method. 相似文献104.
105.
Amaury Herpin Stefan Rohr Dietmar Riedel Nils Kluever Erez Raz Manfred Schartl 《BMC developmental biology》2007,7(1):3
Background
Primordial germ cells (PGCs) give rise to gametes that are responsible for the development of a new organism in the next generation. Two modes of germ line specification have been described: the inheritance of asymmetrically-localized maternally provided cytoplasmic determinants and the induction of the PGC fate by other cell types. 相似文献106.
Mateus Contar Adolfi Peter Fischer Amaury Herpin Martina Regensburger Mariko Kikuchi Minoru Tanaka Manfred Schartl 《Molecular reproduction and development》2019,86(10):1405-1417
In vertebrates, there is accumulating evidence that environmental factors as triggers for sex determination and genetic sex determination are not two opposing alternatives but that a continuum of mechanisms bridge those extremes. One prominent example is the model fish species Oryzias latipes which has a stable XX/XY genetic sex determination system, but still responds to environmental cues, where high temperatures lead to female‐to‐male sex reversal. However, the mechanisms behind are still unknown. We show that high temperatures increase primordial germ cells (PGC) numbers before they reach the genital ridge, which, in turn, regulates the germ cell proliferation. Complete ablation of PGCs led to XX males with germ cell less testis, whereas experimentally increased PGC numbers did not reverse XY genotypes to female. For the underlying molecular mechanism, we provide support for the explanation that activation of the dmrt1a gene by cortisol during early development of XX embryos enables this autosomal gene to take over the role of the male determining Y‐chromosomal dmrt1bY. 相似文献
107.
Carato P Graulich A Jensen N Roth BL Liégeois JF 《Bioorganic & medicinal chemistry letters》2007,17(6):1570-1574
In continuation of our work on N-(piperidin-4-yl)-naphthamides, the effect of substituted benzyl groups on D(2L), D(4.2), and 5-HT(2A) receptor affinity was evaluated. In the 1-naphthamide series most compounds were highly selective for D(4.2) over D(2L) and 5-HT(2A) receptors. Halogen and methyl substitution in position 3 or 4 of the benzyl group increased D(4.2) affinity. In the 2-naphthamide series a similar high D(4.2) over D(2L) selectivity was retained while 5-HT(2A) affinity was increased. 3-Methoxy, 3-methyl, and 4-methyl substituents were favorable for D(4.2) affinity while halogens reduced affinity. 2-Naphthamides with a 3-bromo- or a 3-methyl group were mixed D(4.2)/5-HT(2A) ligands similar to their unsubstituted parent compound. All compounds from both series with significant affinity for D(4.2) and 5-HT(2A) receptors were antagonists. 相似文献
108.
Cristina-Maria Abuhaie Alina Ghinet Amaury Farce Joëlle Dubois Benoît Rigo Elena Bîcu 《Bioorganic & medicinal chemistry letters》2013,23(21):5887-5892
A new family of 30 benzoylated N-ylides 4 and 5 was synthesized and evaluated for the inhibitory activity on human protein farnesyltransferase. Most of these novel compounds possessed in vitro inhibition potencies in the micromolar range. The nature of the substituents on the pyridine and phenyl units proved to be important in determining inhibitory activity and generally, the replacement of the cyanoacrylonitrile function by a cyanoethylacrylate group decreased the biological potential on farnesyltransferase. These results completed our SAR study on this original class of N-ylides. 相似文献
109.
Romain Feron Margot Zahm Cdric Cabau Christophe Klopp Cline Roques Olivier Bouchez Camille Ech Sophie Valire Ccile Donnadieu Pierrick Haffray Anastasia Bestin Romain Morvezen Herv Acloque Peter T. Euclide Ming Wen Elodie Jouano Manfred Schartl John H. Postlethwait Claire Schraidt Mark R. Christie Wesley A. Larson Amaury Herpin Yann Guiguen 《Molecular ecology resources》2020,20(2):531-543
Yellow perch, Perca flavescens, is an ecologically and economically important species native to a large portion of the northern United States and southern Canada and is also a promising candidate species for aquaculture. However, no yellow perch reference genome has been available to facilitate improvements in both fisheries and aquaculture management practices. By combining Oxford Nanopore Technologies long‐reads, 10X Genomics Illumina short linked reads and a chromosome contact map produced with Hi‐C, we generated a high‐continuity chromosome‐scale yellow perch genome assembly of 877.4 Mb. It contains, in agreement with the known diploid chromosome yellow perch count, 24 chromosome‐size scaffolds covering 98.8% of the complete assembly (N50 = 37.4 Mb, L50 = 11). We also provide a first characterization of the yellow perch sex determination locus that contains a male‐specific duplicate of the anti‐Mullerian hormone type II receptor gene (amhr2by) inserted at the proximal end of the Y chromosome (chromosome 9). Using this sex‐specific information, we developed a simple PCR genotyping assay which accurately differentiates XY genetic males (amhr2by+) from XX genetic females (amhr2by?). Our high‐quality genome assembly is an important genomic resource for future studies on yellow perch ecology, toxicology, fisheries and aquaculture research. In addition, characterization of the amhr2by gene as a candidate sex‐determining gene in yellow perch provides a new example of the recurrent implication of the transforming growth factor beta pathway in fish sex determination, and highlights gene duplication as an important genomic mechanism for the emergence of new master sex determination genes. 相似文献
110.
Species abundance distributions in neutral models with immigration or mutation and general lifetimes
Amaury Lambert 《Journal of mathematical biology》2011,63(1):57-72
We consider a general, neutral, dynamical model of biodiversity. Individuals have i.i.d. lifetime durations, which are not
necessarily exponentially distributed, and each individual gives birth independently at constant rate λ. Thus, the population size is a homogeneous, binary Crump–Mode–Jagers process (which is not necessarily a Markov process). We assume that types are clonally inherited. We consider two classes of speciation
models in this setting. In the immigration model, new individuals of an entirely new species singly enter the population at constant rate μ (e.g., from the mainland into the island). In the mutation model, each individual independently experiences point mutations in its germ line, at constant rate θ. We are interested in the species abundance distribution, i.e., in the numbers, denoted I
n
(k) in the immigration model and A
n
(k) in the mutation model, of species represented by k individuals, k = 1, 2, . . . , n, when there are n individuals in the total population. In the immigration model, we prove that the numbers (I
t
(k); k ≥ 1) of species represented by k individuals at time t, are independent Poisson variables with parameters as in Fisher’s log-series. When conditioning on the total size of the
population to equal n, this results in species abundance distributions given by Ewens’ sampling formula. In particular, I
n
(k) converges as n → ∞ to a Poisson r.v. with mean γ/k, where γ : = μ/λ. In the mutation model, as n → ∞, we obtain the almost sure convergence of n
−1
A
n
(k) to a nonrandom explicit constant. In the case of a critical, linear birth–death process, this constant is given by Fisher’s
log-series, namely n
−1
A
n
(k) converges to α
k
/k, where α : = λ/(λ + θ). In both models, the abundances of the most abundant species are briefly discussed. 相似文献