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941.
Rosa E. Rodríguez-Martínez Anastazia T. Banaszak Melanie D. McField Aurora U. Beltrán-Torres Lorenzo álvarez-Filip 《PloS one》2014,9(4)
The once-dominant shallow reef-building coral Acropora palmata has suffered drastic geographical declines in the wider Caribbean from a disease epidemic that began in the late 1970s. At present there is a lack of quantitative data to determine whether this species is recovering over large spatial scales. Here, we use quantitative surveys conducted in 107 shallow-water reef sites between 2010 and 2012 to investigate the current distribution and abundance of A. palmata along the Mesoamerican Reef System (MRS). Using historical data we also explored how the distribution and abundance of this species has changed in the northern portion of the MRS between 1985 and 2010–2012. A. palmata was recorded in only a fifth of the surveyed reef sites in 2010–2012. In the majority of these reef sites the presence of A. palmata was patchy and rare. Only one site (Limones reef), in the northernmost portion of the MRS, presented considerably high A. palmata cover (mean: 34.7%, SD: 24.5%). At this site, the size-frequency distribution of A. palmata colonies was skewed towards small colony sizes; 84% of the colonies were healthy, however disease prevalence increased with colony size. A comparison with historical data showed that in the northern portion of the MRS, in 1985, A. palmata occurred in 74% of the 31 surveyed sites and had a mean cover of 7.7% (SD = 9.0), whereas in 2010–2012 this species was recorded in 48% of the sites with a mean cover of 2.9% (SD = 7.5). A. palmata populations along the MRS are failing to recover the distribution and abundance they had prior to the 1980s. Investigating the biological (e.g., population genetics) and environmental conditions (e.g., sources of stress) of the few standing reefs with relatively high A. palmata cover is crucial for the development of informed restoration models for this species. 相似文献
942.
Patricia Rohs Alicia M. Ebert Ania Zuba Sarah McFarlane 《Gene expression patterns : GEP》2013,13(8):354-361
Fibroblast growth factor (FGF) signaling is important for a host of developmental processes such as proliferation, differentiation, tissue patterning, and morphogenesis. In vertebrates, FGFs signal through a family of four fibroblast growth factor receptors (FGFR 1-4), one of which is duplicated in zebrafish (FGFR1). Here we report the mRNA expression of the five known zebrafish fibroblast growth factor receptors at five developmental time points (24, 36, 48, 60, and 72 h postfertilization), focusing on expression within the central nervous system. We show that the receptors have distinct and dynamic expression in the developing zebrafish brain, eye, inner ear, lateral line, and pharynx. In many cases, the expression patterns are similar to those of homologous FGFRs in mouse, chicken, amphibians, and other teleosts. 相似文献
943.
Maite Beltrán Marta Maseda Yolanda Pérez Jordi Robles Enrique Pedroso Anna Grandas 《Nucleosides, nucleotides & nucleic acids》2013,32(7-9):1487-1488
Abstract Hydroxylated amino acids can be introduced in nucleopeptides using the acetyl group for their side chain protection. Base-stable nucleopeptide analogues are obtained if homoserine is used as the linking residue. 相似文献
944.
Ariana Zoppi Alicia Delrivo Virginia Aiassa Marcela Raquel Longhi 《AAPS PharmSciTech》2013,14(2):727-735
β-cyclodextrin (βCD) and methyl-β-cyclodextrin (MβCD) complexes with sulfamethazine (SMT) were prepared and characterized by different experimental techniques, and the effects of βCD and MβCD on drug solubility were assessed via phase-solubility analysis. The phase-solubility diagram for the drug showed an increase in water solubility, with the following affinity constants calculated: 40.4 ± 0.4 (pH 2.0) and 29.4 ± 0.4 (pH 8.0) M−1 with βCD and 56 ± 1 (water), 39 ± 3 (pH 2.0) and 39 ± 5 (pH 8.0) M−1 with MβCD. According to 1H NMR and 2D NMR spectroscopy, the complexation mode involved the aromatic ring of SMT included in the MβCD cavity. The complexes obtained in solid state by freeze drying were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and thermal analysis. The amorphous complexes obtained in this study may be useful in the preparation of pharmaceutical dosage forms of SMT. 相似文献
945.
Fan Wu Andrea Kirmaier Robert Goeken Ilnour Ourmanov Laura Hall Jennifer S. Morgan Kenta Matsuda Alicia Buckler-White Keiko Tomioka Ronald Plishka Sonya Whitted Welkin Johnson Vanessa M. Hirsch 《PLoS pathogens》2013,9(8)
The antagonistic interaction with host restriction proteins is a major driver of evolutionary change for viruses. We previously reported that polymorphisms of the TRIM5α B30.2/SPRY domain impacted the level of SIVsmm viremia in rhesus macaques. Viremia in macaques homozygous for the non-restrictive TRIM5α allele TRIM5Q was significantly higher than in macaques expressing two restrictive TRIM5alpha alleles TRIM5TFP/TFP or TRIM5Cyp/TFP. Using this model, we observed that despite an early impact on viremia, SIVsmm overcame TRIM5α restriction at later stages of infection and that increasing viremia was associated with specific amino acid substitutions in capsid. Two amino acid substitutions (P37S and R98S) in the capsid region were associated with escape from TRIM5TFP restriction and substitutions in the CypA binding-loop (GPLPA87-91) in capsid were associated with escape from TRIM5Cyp. Introduction of these mutations into the original SIVsmE543 clone not only resulted in escape from TRIM5α restriction in vitro but the P37S and R98S substitutions improved virus fitness in macaques with homozygous restrictive TRIMTFP alleles in vivo. Similar substitutions were observed in other SIVsmm strains following transmission and passage in macaques, collectively providing direct evidence that TRIM5α exerts selective pressure on the cross-species transmission of SIV in primates. 相似文献
946.
947.
948.
Ángel Urzúa Guillermo Guerao Jose A. Cuesta Guiomar Rotllant Alicia Estévez Klaus Anger 《Marine and Freshwater Behaviour and Physiology》2013,45(6):381-397
Palaemonetes zariquieyi, an endemic palaemonid species of shrimp that lives in freshwater and brackish coastal habitats in eastern Spain, shows an abbreviated, non-feeding larval development comprising only three zoeal stages. To identify the endogenous bioenergetic fuel that allows for food-independent development from hatching to metamorphosis, larvae were reared under controlled laboratory conditions, and ontogenetic changes in dry weight (W), elemental (CHN), and lipid composition (total lipids, principal lipid classes, and fatty acids [FA]) were quantified at the onset of each zoeal stage and in the first juvenile. Values of W, C, and H per larva and per mass unit of W decreased throughout the time of larval development, while the N content showed only a weak decline (suggesting strong lipid but only little protein degradation). Correspondingly, directly measured values of total lipids (both in μg/larva and in % of W) decreased gradually, with neutral lipids (NL) consistently remaining the predominant and most strongly used fraction; sterol esters and waxes were not detected. In contrast to the NL, the fraction of polar lipids (PL) per larva remained stable and, as a consequence, tended to increase as a percentage of total lipids. Likewise, other important lipid fractions such as free FA and cholesterol remained stable throughout the time of larval development. Among the FA, palmitic (16:0), oleic (18:1n–9), linoleic (18:2n–6), and eicosapentaenoic (20:5n–3) acid were predominant, showing a significant decrease during larval development; stearic (18:0), vaccenic (18:1n–7), and arachidonic acid (20:4n–6) were found only in small amounts. Our results indicate that the lecithotrophic development of P. zariquieyi is primarily fuelled by the utilization of lipids (especially triacylglycerides and other NL), which is reflected by a decreasing carbon content. Proteins and PL, by contrast, are preserved as structurally indispensable components (nerve and muscle tissues, cell membranes). The abbreviated and non-feeding mode of larval development of P. zariquieyi may have an adaptive value in land-locked freshwater habitats, where planktonic food limitation is likely to occur. The patterns of reserve utilization are similar to those previously observed in other palaemonid shrimps and various other groups of decapod crustaceans with lecithotrophic larvae. This suggests a multiple convergent evolution of bioenergetic traits allowing for reproduction in food-limited aquatic environments. 相似文献
949.
Soresi Daniela Bagnaresi Paolo Crescente Juan Manuel Díaz Marina Cattivelli Luigi Vanzetti Leonardo Carrera Alicia 《Plant Molecular Biology Reporter》2021,39(4):710-726
Plant Molecular Biology Reporter - Qfhs.ndsu-3AS in wild emmer wheat (Triticum turgidum L. ssp. dicoccoides) is a major quantitative trait locus associated with type II resistance to Fusarium head... 相似文献
950.
Hernández Tienda Clara Beltrán Francés Víctor Majolo Bonaventura Romero Teresa Illa Maulany Risma Oka Ngakan Putu Amici Federica 《International journal of primatology》2021,42(4):528-532
International Journal of Primatology - Snake predation is considered an important evolutionary force for primates. Yet, very few studies have documented encounters between primates and snakes in... 相似文献