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991.
PA Avelar Ferreira CA Bomfeti B Lima Soares FM de Souza Moreira 《World journal of microbiology & biotechnology》2012,28(5):1947-1959
One of the most cultivated and consumed vegetables in Brazil is the common bean, Phaseolus vulgaris L. The symbiosis of this plant species with nitrogen-fixing bacteria that are adapted to the stresses commonly found in tropical
soils can increase production. The aim of this study was to evaluate the symbiotic effectiveness of bacterial strains from
soils under different land uses in the Amazon region. Further, rhizobia tolerance to acidity and aluminium and the involvement
of some possible physiological mechanisms of such tolerance were also investigated. In assessing the efficiency of biological
nitrogen fixation, inoculation with strains UFLA04-195, UFLA04-173 and UFLA04-202, belonging to the genus Rhizobium, resulted in greater plant growth, higher shoot nitrogen content and good nodulation compared to the inoculation with the
strain CIAT 899 (R. tropici), and to the mineral nitrogen control or Burkholderia fungorum strains that nodulated or not bean plants. These efficient strains grew better at pH 5.0 than at pH 6.0 or pH 6.9; they also
tolerated up to 1 mmol l−1 of Al3+ and showed an increased production of exopolysaccharides where the growing rates were less (pH 6.0 and pH 6.9). With respect
to aluminium, the highest production of EPS produced greater tolerance to this element. Taken together, these results indicate
that the strains evaluated in this study were tolerant to acidity and aluminium; they appeared to have developed resistance
mechanisms such as EPS production and a resistant cell outer membrane (indicated by resistance to polymyxin and methyl violet).
As these strains also gave increased yields of the host species, further studies on whether to recommend these strains as
inoculants are already underway. 相似文献
992.
993.
AimsAn extensive variety of prenatal insults are associated with an increased incidence of metabolic and cardiovascular disorders in adult life. We previously demonstrated that maternal global nutrient restriction during pregnancy leads to increased blood pressure and endothelial dysfunction in the adult offspring. This study aimed to assess whether prenatal exposure to nutritional insult has transgenerational effects in F2 and F3 offspring.Main methodsFor this, female Wistar rats were randomly divided into two groups on day 1 of pregnancy: a control group fed standard chow ad libitum and a restricted group fed 50% of the ad libitum intake throughout gestation. At delivery, all animals were fed a standard laboratory chow diet. At 11 weeks of age, one female and one male from each restricted litter were randomly selected and mated with rats from another restricted litters in order to generate the F2 offspring. The same procedure produced F3 generation. Similarly, the rats in the control group were bred for each generation.Key FindingsOur findings show that the deleterious effects of maternal nutrient restriction to which the F0 mothers were exposed may not be limited to the male first generation. In fact, we found that elevated blood pressure, an impaired vasodilatory response to acetylcholine and alterations in NO production were all transferred to the subsequent males from F2 and F3 generations.SignificanceOur data show that global nutrient restriction during pregnancy results in a specific phenotype that can be passed transgenerationally to a second and third generation. 相似文献
994.
Gunz P Neubauer S Golovanova L Doronichev V Maureille B Hublin JJ 《Journal of human evolution》2012,62(2):300-313
The globular braincase of modern humans is distinct from all fossil human species, including our closest extinct relatives, the Neandertals. Such adult shape differences must ultimately be rooted in different developmental patterns, but it is unclear at which point during ontogeny these group characteristics emerge.Here we compared internal shape changes of the braincase from birth to adulthood in Neandertals (N = 10), modern humans (N = 62), and chimpanzees (N = 62). Incomplete fossil specimens, including the two Neandertal newborns from Le Moustier 2 and Mezmaiskaya, were reconstructed using reference-based estimation methods. We used 3D geometric morphometrics to statistically compare shapes of virtual endocasts extracted from computed-tomographic scans. Throughout the analysis, we kept track of possible uncertainties due to the missing data values and small fossil sample sizes.We find that some aspects of endocranial development are shared by the three species. However, in the first year of life, modern humans depart from this presumably ancestral pattern of development. Newborn Neandertals and newborn modern humans have elongated braincases, and similar endocranial volumes. During a ‘globularization-phase’ modern human endocasts change to the globular shape that is characteristic for Homo sapiens. This phase of early development is unique to modern humans, and absent from chimpanzees and Neandertals.Our results support the notion that Neandertals and modern humans reach comparable adult brain sizes via different developmental pathways. The differences between these two human groups are most prominent directly after birth, a critical phase for cognitive development. 相似文献
995.
Bell IM Stump CA Gallicchio SN Staas DD Zartman CB Moore EL Sain N Urban M Bruno JG Calamari A Kemmerer AL Mosser SD Fandozzi C White RB Zrada MM Selnick HG Graham SL Vacca JP Kane SA Salvatore CA 《Bioorganic & medicinal chemistry letters》2012,22(12):3941-3945
Rational modification of the clinically tested CGRP receptor antagonist MK-3207 (3) afforded an analogue with increased unbound fraction in rat plasma and enhanced aqueous solubility, 2-[(8R)-8-(3,5-difluorophenyl)-8-methyl-10-oxo-6,9-diazaspiro[4.5]dec-9-yl]-N-[(6S)-2'-oxo-1',2',5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3'-pyrrolo[2,3-b]pyridin]-3-yl]acetamide (MK-8825) (6). Compound 6 maintained similar affinity to 3 at the human and rat CGRP receptors but possessed significantly improved in vivo potency in a rat pharmacodynamic model. The overall profile of 6 indicates it should find utility as a rat tool to investigate effects of CGRP receptor blockade in vivo. 相似文献
996.
997.
Laurent Boulanger Bruno Passet Eric Pailhoux Jean-Luc Vilotte 《Transgenic research》2012,21(6):1183-1190
Compared to experiments involving pigs, cows and/or sheep, transgenesis applied to goats is probably less advertised. However, recent successes and increasing amount of dedicated research make this species of special interest for ongoing biological and physiological questions on genome engineering in large animals. This short review aims at highlighting the current applications and limitations of the goat genome manipulation. 相似文献
998.
Most studies of c-Jun N-terminal Kinase (JNK) activation in retinal tissue were done in the context of neurodegeneration. In this study, we investigated the behavior of JNK during mitosis of progenitor cells in the retina of newborn rats. Retinal explants from newborn rats were kept in vitro for 3 hours and under distinct treatments. Sections of retinal explants or freshly fixed retinal tissue were used to detect JNK phosphorylation by immunohistochemistry, and were examined through both fluorescence and confocal microscopy. Mitotic cells were identified by chromatin morphology, histone-H3 phosphorylation, and location in the retinal tissue. The subcellular localization of proteins was analyzed by double staining with both a DNA marker and an antibody to each protein. Phosphorylation of JNK was also examined by western blot. The results showed that in the retina of newborn rats (P1), JNK is phosphorylated during mitosis of progenitor cells, mainly during the early stages of mitosis. JNK1 and/or JNK2 were preferentially phosphorylated in mitotic cells. Inhibition of JNK induced cell cycle arrest, specifically in mitosis. Treatment with the JNK inhibitor decreased the number of cells in anaphase, but did not alter the number of cells in either prophase/prometaphase or metaphase. Moreover, cells with aberrant chromatin morphology were found after treatment with the JNK inhibitor. The data show, for the first time, that JNK is activated in mitotic progenitor cells of developing retinal tissue, suggesting a new role of JNK in the control of progenitor cell proliferation in the retina. 相似文献
999.
Yang XR Brown K Landi MT Ghiorzo P Badenas C Xu M Hayward NK Calista D Landi G Bruno W Bianchi-Scarrà G Aguilera P Puig S Goldstein AM Tucker MA 《Pigment cell & melanoma research》2012,25(2):243-247
Copy number variations (CNVs) have been shown to contribute substantially to disease susceptibility in several inherited diseases including cancer. We conducted a genome-wide search for CNVs in blood-derived DNA from 79 individuals (62 melanoma patients and 17 spouse controls) of 30 high-risk melanoma-prone families without known segregating mutations using genome-wide comparative genomic hybridization (CGH) tiling arrays. We identified a duplicated region on chromosome 4q13 in germline DNA of all melanoma patients in a melanoma-prone family with three affected siblings. We confirmed the duplication using quantitative PCR and a custom-made CGH array design spanning the 4q13 region. The duplicated region contains 10 genes, most of which encode CXC chemokines. Among them, CXCL1 (melanoma growth-stimulating activity α) and IL8 (interleukin 8) have been shown to stimulate melanoma growth in vitro and in vivo. Our data suggest that the alteration of CXC chemokine genes may confer susceptibility to melanoma. 相似文献