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191.
Alcántara-Hernández RJ Rodríguez-Álvarez JA Valenzuela-Encinas C Gutiérrez-Miceli FA Castañón-González H Marsch R Ayora-Talavera T Dendooven L 《Letters in applied microbiology》2010,51(5):558-563
Aims: To characterize the bacterial community of taberna, an alcoholic traditional beverage from the Southern part of Mexico produced by the fermentation of the coyol palm sap (Acrocomia aculeate). Methods and Results: Bacterial 16S rDNA libraries were constructed from metagenomic DNA extracted during the fermentation process at 0, 60 and 108 h. A total of 154 clones were sequenced, and 13, 10 and nine unique sequences were found at each sampling time. At the onset of the fermentation, Zymomonas mobilis, Fructobacillus spp., Pantoea agglomerans and other Gammaproteobacteria were detected. After 60 h, lactic acid bacteria were found and 30% of clones in the library were related to Lactobacillus nagelii, L. sucicola and L. sp. By the end of the experiment, i.e. after 108 h, the bacterial community included Z. mobilis, Lact. nagelii and Acetobacter pasteurianus. Conclusions: Our results suggest that Z. mobilis population represented an important proportion of the bacterial community (60–80%), as well as the lactobacilli during the fermentation process. The bacterial diversity was low and decreased as the fermentation progressed. Significance and Impact of the Study: This culture‐independent study suggests that Z. mobilis and lactobacilli play an important role in the alcoholic fermentation of the taberna beverage. 相似文献
192.
Ákos Boros Ildikó Somogyi Péter Engelmann Andrea Lubics Dóra Reglodi Edit Pollák László Molnár 《Cell and tissue research》2010,339(3):649-653
Pituitary adenylate cyclase activating polypeptide (PACAP)-like molecules have been shown to be present in cocoon albumin
and in Eisenia fetida embryos at an early developmental stage (E1) by immunocytochemistry and radioimmunoassay. Here, we focus on detecting the
stage at which PAC1 receptor (PAC1R)-like immunoreactivity first appears in germinal layers and structures, e.g., various
parts of the central nervous system (CNS), in developing earthworm embryos. PAC1R-like immunoreactivity was revealed by Western
blot and Far Western blot as early as the E2 developmental stage, occurring in the ectoderm and later in specific neurons
of the developing CNS. Labeled CNS neurons were first seen in the supraesophageal ganglion (brain) and subsequently in the
subesophageal and ventral nerve cord ganglia. Ultrastructurally, PAC1Rs were located mainly on plasma membranes and intracellular
membranes, especially on cisternae of the endoplasmic reticulum. Therefore, PACAP-like compounds probably influence the differentiation
of germinal layers (at least the ectoderm) and of some neurons and might act as signaling molecules during earthworm embryonic
development. 相似文献
193.
Bánóczi Z Gorka-Kereskényi Á Reményi J Orbán E Hazai L Tökési N Oláh J Ovádi J Béni Z Háda V Szántay C Hudecz F Kalaus G Szántay C 《Bioconjugate chemistry》2010,21(11):1948-1955
Vinblastine is a widely used anticancer drug with undesired side effects. Its conjugation with carrier molecules could be an efficient strategy to reduce these side effects. Besides this, the conjugate could exhibit increased efficiency against resistant cells, e.g., due to the altered internalization pathway. Oligoarginines, as cell-penetrating peptides, can transport covalently attached compounds into different kinds of cells and enhance the efficiency of those compounds. We report here the coupling of vinblastine through its carboxyl group at position 16 with the N-terminal amino function of L-Trp methyl ester. After hydrolysis of the ester group, 17-desacetylvinblastineTrp was conjugated to the N-terminal amino group of oligoarginine via the C-terminal carboxyl group of the Trp moiety in solution. The antitumor effect of conjugates was studied on sensitive and resistant human leukemia (HL-60) cells in vitro. Our data suggest that all conjugates investigated possess an antiproliferative effect against the studied cells. However, the effect was dependent on the number of Arg residues in the conjugates: Arg? > Arg? ? Arg?. The conjugate with Arg? exhibited similar efficicacy as compared with free 17-desacetylvinblastineTrp. The in vitro studies also showed that the tubulin binding ability of vinblastine was essentially preserved even in the octaarginine conjugate. We also observed that two isomers were formed during conjugation. These isomers showed different levels of activity against tubulin polymerization in vitro and in vivo. The 17-desacetylvinblastineTrp-Arg?-1 isomer conjugate possessed high selectivity against the mitotic spindles. HRMS and NMR data suggest that 17-desacetylvinblastineTrp-Arg?-1 and 17-desacetylvinblastineTrp-Arg?-2 are epimers at the tryptophan α carbon atom. 相似文献
194.
Álvarez-Buylla ER Ambrose BA Flores-Sandoval E Englund M Garay-Arroyo A García-Ponce B de la Torre-Bárcena E Espinosa-Matías S Martínez E Piñeyro-Nelson A Engström P Meyerowitz EM 《The Plant cell》2010,22(11):3543-3559
Spontaneous homeotic transformations have been described in natural populations of both plants and animals, but little is known about the molecular-genetic mechanisms underlying these processes in plants. In the ABC model of floral organ identity in Arabidopsis thaliana, the B- and C-functions are necessary for stamen morphogenesis, and C alone is required for carpel identity. We provide ABC model-based molecular-genetic evidence that explains the unique inside-out homeotic floral organ arrangement of the monocotyledonous mycoheterotroph species Lacandonia schismatica (Triuridaceae) from Mexico. Whereas a quarter million flowering plant species bear central carpels surrounded by stamens, L. schismatica stamens occur in the center of the flower and are surrounded by carpels. The simplest explanation for this is that the B-function is displaced toward the flower center. Our analyses of the spatio-temporal pattern of B- and C-function gene expression are consistent with this hypothesis. The hypothesis is further supported by conservation between the B-function genes of L. schismatica and Arabidopsis, as the former are able to rescue stamens in Arabidopsis transgenic complementation lines, and Ls-AP3 and Ls-PI are able to interact with each other and with the corresponding Arabidopsis B-function proteins in yeast. Thus, relatively simple molecular modifications may underlie important morphological shifts in natural populations of extant plant taxa. 相似文献
195.
Ricardo Estrada María Herrera lvaro Segura Javier Araya Carlos Boschini Jos María Gutirrez Guillermo Len 《Biologicals》2010,38(6):664-669
Administration of antivenoms to treat snakebite envenomings has the potential risk of inducing early adverse reactions. The mechanisms involved in these reactions are unclear. In this study, polyspecific antivenom consisting of whole IgG purified from equine plasma by caprylic acid precipitation was administered intravenously to non-envenomed horses (n = 47) and cows (n = 20) at a dose of 0.4 mL/kg. It has been reported that, in humans, this formulation (administered at a dose of 0.4 mL/kg) induces mild noticeable early adverse reactions, such as fever, vomiting, diarrhea, urticaria, generalized rash, tachypnea or tachycardia, in about 15–20% of the patients. Unexpectedly, none of the animals receiving antivenom in our study showed any evidence of early adverse reaction. Moreover, no late adverse reactions, i.e. serum sickness, were observed during 40 days after antivenom administration. Unlike studies performed in envenomed humans, our present results were obtained in a group of non-envenomed individuals. It is concluded that, in addition to the physicochemical characteristics of the formulation, other unknown factors must determine the occurrence of adverse reactions in snakebite envenomed humans treated with equine-derived antivenoms. 相似文献
196.
Fernando Rodríguez‐Serrano Pablo Álvarez Octavio Caba Manuel Picón Juan A. Marchal Macarena Perán José Prados Consolación Melguizo Ana R. Rama Houria Boulaiz Antonia Aránega 《Cell biology international》2010,34(9):917-924
Adult stem cells are becoming the best option for regenerative medicine because they have low tumourigenic potential and permit autologous transplantation, even without in vitro culture. Our objectives were to evaluate the effects of exogenous nucleosides on the proliferation of hASCs (human adipose‐derived stem cells), with or without co‐treatment with 5‐aza (5‐azacytidine), and to analyse the expression of lamin A/C during cardiomyocyte differentiation of these cells. We isolated hASCs from human lipoaspirates that were positive for mesenchymal stem cell markers. We found that 5‐aza induces a dose‐dependent inhibition of hASC proliferation [IC50 (inhibitory concentration 50): 5.37 μM], whereas exogenous nucleosides significantly promote the proliferation of hASCs and partially revert the antiproliferative effect of the drug. Multipotentiality of isolated hASCs was confirmed by adipogenic, osteogenic and cardiomyogenic induction. 5‐Aza‐induced cells expressed cardiac troponins I and T and myosin light chain 2, myocardial markers that were directly correlated with lamin A/C expression. Our results support the importance of the nucleoside supplementation of media to improve conditions for the expansion and maintenance of hASCs in culture. In addition, the quantification of lamin A/C expression appears to be a good marker for the characterization of cardiomyocyte differentiation of stem cells that has rarely been used. 相似文献
197.
198.
Ángel De Frutos Pedro P. Olea Patricia Mateo-Tomás Francisco J. Purroy 《European Journal of Wildlife Research》2010,56(4):503-511
The maintenance of fallows has been shown to prevent the loss of farmland biodiversity caused by agricultural intensification.
These are mainly introduced as part of both obligatory and voluntary set-aside schemes. However, the obligatory set-aside
has recently been abolished by the Common Agricultural Policy Health Check. In this study, we examine the role of fallow in
fine-grained habitat use by a threatened farmland bird (Lesser Kestrel) during summer in northwestern Spain. To analyze Lesser
Kestrel occurrence, we used generalized linear models, a theoretic-information approach and a hierarchical partitioning analysis.
The best AIC-based models explaining occurrence of Lesser Kestrels showed that fallow was the more important habitat type
followed, to a lesser extent, by dry cereal stubble and field margin. In contrast, irrigated crops negatively influenced occurrence.
Heterogeneity of crop mosaic was not important in explaining occurrence of Lesser Kestrel. Fallows, like dry cereal stubbles
and field margins, seem to be suitable for foraging given the abundance of high food resources and their availability due
to shorter vegetation cover. The abolition of the obligatory set-aside could reduce the total surface of fallow land (approximately
40.9%), likely affecting habitat use by Lesser Kestrel through an increase of other non-preferred crops (e.g., irrigated crops)
or by decreasing food resources. Agri-environment schemes focusing on the maintenance of low-intensive farming systems with
a mosaic of crops and semi-natural habitats interspersed should be promoted in premigratory areas to maintain Lesser Kestrel. 相似文献
199.
A global approach to crop wild relative conservation: securing the gene pool for food and agriculture 总被引:1,自引:0,他引:1
Nigel Maxted Shelagh Kell Álvaro Toledo Ehsan Dulloo Vernon Heywood Toby Hodgkin Danny Hunter Luigi Guarino Andy Jarvis Brian Ford-Lloyd 《Kew Bulletin》2010,65(4):561-576
In light of the growing concern over the potentially devastating impacts on biodiversity and food security of climate change
and the massively growing world population, taking action to conserve crop wild relatives (CWR), is no longer an option —
it is a priority. Crop wild relatives are species closely related to crops, including their progenitors, many of which have
the potential to contribute beneficial traits to crops, such as pest or disease resistance, yield improvement or stability.
They are a critical component of plant genetic resources for food and agriculture (PGRFA), have already made major contributions
to crop production and are vital for future food security; their systematic conservation in ways that ensure their continuing
availability for use is therefore imperative. This is a complex, interdisciplinary, global issue that has been addressed by
various national and international initiatives. Drawing on the lessons learnt from these initiatives we can now propose a
global approach to CWR conservation, the key elements of which are: (1) estimating global CWR numbers, (2) assessment of the
global importance of CWR diversity, (3) current conservation status, (4) threats to CWR diversity, (5) systematic approaches
to CWR conservation, (6) CWR informatics, and (7) enhancing the use of CWR diversity. 相似文献
200.
ELENA V. ERMILOVA ZHANNETA M. ZALUTSKAYA MAXIM M. NIKITIN TATYANA V. LAPINA EMILIO FERNÁNDEZ 《Plant, cell & environment》2010,33(6):1049-1056
The unicellular green alga Chlamydomonas reinhardtii is able to take up methylammonium/ammonium from the medium at different stages of its sexual life cycle. Vegetative cells and pre‐gametes mostly used a low‐affinity system (LATS) component, but gametes obtained after light treatment of N‐deprived pre‐gametes expressed both LATS and high‐affinity system (HATS) components for the uptake of methylammonium/ammonium. The activity of the LATS component was stimulated by light in only 5 min in a process independent of protein synthesis. By using the lrg6 mutant that produces sexually competent gametes in the dark, light effects on ammonium transport and gamete differentiation have been separately analysed. We have found light regulation of four Amt1 genes: Amt1; 1, Amt1; 2, Amt1; 4 and Amt1; 5. Whereas light‐dependent expression of Amt1; 1, Amt1; 2 and Amt1; 4 was independent of gametogenesis, and that of Amt1; 5 was activated in the lrg6 mutant, suggesting a connection between this transporter and the subsequent events taking place during gametogenesis. 相似文献