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991.
Said Amrani Nazhat-Ezzaman Noureddine Tej Bhatnagar Montserrat Argandoña Joaquin J. Nieto Carmen Vargas 《Systematic and applied microbiology》2010
Twenty seven rhizobial strains associated with Acacia saligna grown in northern and southern Algeria were characterized, including generation time, host-range, the 16S rRNA gene and 16S–23S rRNA intergenic spacer restriction patterns, 16S rRNA gene sequence analysis and tolerance to salinity and drought. Cross inoculation tests indicated that 11 slow-growing isolates from northern nurseries were able to nodulate introduced Australian acacias exclusively, whereas 16 fast-growing isolates, mainly from southern nurseries, were capable of also nodulating native acacias. Restriction patterns and sequence analysis of the 16S rRNA gene showed that strains of the first group belonged to Bradyrhizobium while strains of the second group were related to Sinorhizobium meliloti and Rhizobium gallicum. Interestingly, five strains of the first group formed a distinct cluster phylogenetically close to Bradyrhizobium betae, a non-nodulating species causing tumour-like deformations in sugar beet roots. Bradyrhizobium strains were in general more sensitive to NaCl and PEG than the S. meliloti and R. gallicum representatives. Among the latter, strains S. meliloti BEC1 and R. gallicum DJA2 were able to tolerate up to 1 M NaCl and 20% PEG. This, together with their wide host-range among Acacia species, make them good candidates for developing inoculants for A. saligna and other acacia trees growing in arid areas. 相似文献
992.
Igor Beseda Laszlo Czollner Priti S. Shah Rupesh Khunt Rawindra Gaware Paul Kosma Christian Stanetty Maria Carmen del Ruiz-Ruiz Hassan Amer Kurt Mereiter Thierry Da Cunha Alex Odermatt Dirk Claßen-Houben Ulrich Jordis 《Bioorganic & medicinal chemistry》2010,18(1):433-454
The effect of glycyrrhetinic acid (GA) and GA-derivatives towards 11β-hydroxysteroid dehydrogenase (11β-HSD) was investigated. Novel compounds with modifications at positions C-3, C-11 and C-29 of the GA skeleton were prepared. Single crystal X-ray diffraction data of selected substances are reported and discussed. 相似文献
993.
Zinc plays important roles in numerous cellular activities and physiological functions. Intracellular zinc levels are strictly
maintained by zinc homeostatic mechanisms. Zinc concentrations in the prostate are the highest of all soft tissues and could
be important for prostate health. However, the mechanisms by which the prostate maintains high zinc levels are still unclear.
In addition, the response of the prostate to alterations in dietary zinc is unknown. The current study explored cellular zinc
levels and zinc transporter expression profiles in the lobes of the prostate during dietary marginal zinc depletion. Rats
were given either zinc-adequate (ZA, 30 mg Zn/kg) or marginal zinc-deficient (MZD, 5 mg Zn/kg) diet for 9 weeks. In addition,
a subgroup of the MZD rats was supplemented with phytase (1,500 unit/kg diet) to improve zinc bioavailability. We found that
both zinc concentrations and ZnT2 expression in the prostate dorsolateral lobes were substantially higher than in the ventral
lobes (P < 0.05). Marginal zinc depletion significantly decreased ZnT2 expression in the dorsolateral lobes (P < 0.05), and phytase supplementation had a trend to increase ZnT2 expression. In addition, of all measured zinc transporters,
only ZnT2 mRNA abundance was significantly correlated to the zinc concentrations in the dorsolateral lobe. No correlations
were found between zinc transporter expression and zinc concentrations in the ventral lobes. These results indicate that ZnT2
may play a significant role in the maintenance of zinc homeostasis in the prostate. 相似文献
994.
Gabriel Navarrete-Vázquez Sergio Hidalgo-Figueroa Mariana Torres-Piedra Jorge Vergara-Galicia Julio Cesar Rivera-Leyva Samuel Estrada-Soto Ismael León-Rivera Berenice Aguilar-Guardarrama Yolanda Rios-Gómez Rafael Villalobos-Molina Maximiliano Ibarra-Barajas 《Bioorganic & medicinal chemistry》2010,18(11):3985-3991
A series of 1H-benzo[d]imidazole analogues of Pimobendan, substituted at position 5 with either –CF3 or –NO2, were synthesized using a short synthetic route. All the nitro derivatives were potent, and exhibited a concentration- and partial endothelium-dependent vasorelaxant effects, with EC50s <5 μM. 2-Methoxy-4-[5-nitro-1H-benzo[d]imidazol-2-yl]phenol (compound 13) was the most potent derivative of the series, showing an EC50 value of 1.81 μM and Emax of 91.7% for ex vivo relaxant response in intact aortic rings, resulting in a 2.5-fold higher activity compared to Pimobendan. The closely related 5-CF3 analogue (compound 8), was 19 times less potent than 13. The antihypertensive activity of compound 13 was evaluated at doses of 25, 50 and 100 mg kg?1, using spontaneously hypertensive rats (SHR), showing a statistically significant dose-dependent effect. 相似文献
995.
María Mu?oz Ana Isabel Fernández Cristina óvilo Gloria Mu?oz Carmen Rodriguez Almudena Fernández Estefania Alves Luis Silió 《遗传、选种与进化》2010,42(1):23
Background
The aim of this work was to study the effects on litter size of variants of the porcine genes RBP4, ESR1 and IGF2, currently used in genetic tests for different purposes. Moreover, we investigated a possible effect of the interaction between RBP4-MspI and ESR1-PvuII polymorphisms. The IGF2-intron3-G3072A polymorphism is actually used to select lean growth, but other possible effects of this polymorphism on reproductive traits need to be evaluated.Methods
Detection of polymorphisms in the genomic and cDNA sequences of RBP4 gene was carried out. RBP4-MspI and IGF2-intron3-G3072A were genotyped in a hyperprolific Chinese-European line (Tai-Zumu) and three new RBP4 polymorphisms were genotyped in different pig breeds. A bivariate animal model was implemented in association analyses considering the number of piglets born alive at early (NBA12) and later parities (NBA3+ ) as different traits. A joint analysis of RBP4-MspI and ESR1-PvuII was performed to test their possible interaction. In the IGF2 analysis, paternal or maternal imprinting effects were also considered.Results
Four different RBP4 haplotypes were detected (TGAC, GGAG, GAAG and GATG) in different pig breeds and wild boars. A significant interaction effect between RBP4-MspI and ESR1-PvuII polymorphisms of 0.61 ± 0.29 piglets was detected on NBA3+. The IGF2 analysis revealed a significant increase on NBA3+ of 0.74 ± 0.37 piglets for the paternally inherited allele A.Conclusions
All the analyzed pig and wild boar populations shared one of the four detected RBP4 haplotypes. This suggests an ancestral origin of the quoted haplotype. The joint use of RBP4-MspI and ESR1-PvuII polymorphisms could be implemented to select for higher prolificacy in the Tai-Zumu line. In this population, the paternal allele IGF2-intron3-3072A increased litter size from the third parity. The non-additive effects on litter size reported here should be tested before implementation in other pig breeding schemes. 相似文献996.
Esther Lizárraga-Mollinedo Elisa Fernández-Millán Laura de Miguel-Santos† Carlos José Martínez-Honduvilla† Carmen Alvarez† Fernando Escrivᆠ《Journal of neurochemistry》2010,112(1):123-133
Exposure to maternal undernutrition during development increases the risk for neurological and cognitive defects. However, little is known about the underlying mechanisms involved. Peripheral responses to insulin are increased following food-restriction, thus the possibility arises that brain insulin actions are affected by undernutrition, causing damages to the higher cerebral functions. In this study, we examined the effects of early undernutriton on molecular targets of insulin actions such as glucose transporters, glycogen, glycogen synthase kinase-3 (GSK3) and mitogen-activated protein kinases, as well as proteins involved in apoptosis in the cortex from 10-day-old rats. We show that undernutrition results in an enhanced glycogen content which is confined to astrocytes, according to our histochemical approaches. Cortical phospho-GSK3 is also increased. In addition to glycogen synthesis, GSK3 regulates crucial cellular processes. Therefore, its elevated degree of phosphorylation may have an impact on these processes and, consequently, on the cortical development. Phospho-p38 and both total JNK and phospho-JNK, which regulate apoptosis, are reduced following undernutrition. However, cleaved caspase 3 is not altered, which suggests that this condition does not induce extensive modifications to the cortical apoptosis. Thus, our results indicate that undernutrition gives rise to molecular alterations that may have repercussions on cerebral cortex development and functions. 相似文献
997.
998.
Bone responds to changes in its mechanical environment, but the mechanisms by which it does so are poorly understood. One hypothesis of mechanosensing in bone states that osteocytes can sense the flow of fluid through the canalicular system. To study this in vitro a number of fluid flow devices have been designed in which cells are placed between parallel plates in sealed chambers. Fluid flows through the chambers at controlled rates, most commonly driven by a peristaltic pump. In addition to fluid flow, high pressures have been observed in these chambers, but the effect of this on the cellular responses has generally been ignored or considered irrelevant, something challenged by recent cellular experiments using pressure only. We have, therefore, devised a system in which we can considerably reduce the pressure while maintaining the flow rate to enable study of their effects individually and in combination. As reducing pressure also reduces the risk of leaks in flow chambers, our system is suitable for real-time microscopical experiments. We present details of the new systems and of experiments with osteoblasts to illustrate the effects of fluid flow with and without additional pressure on the translocation of β-catenin to the nucleus. 相似文献
999.
Patricia Bernal Sandrine Lemaire Mariana G. Pinho Shahriar Mobashery Jason Hinds Peter W. Taylor 《The Journal of biological chemistry》2010,285(31):24055-24065
Epicatechin gallate (ECg) sensitizes methicillin-resistant Staphylococcus aureus (MRSA) to oxacillin and other β-lactam agents; it also reduces the secretion of virulence-associated proteins, prevents biofilm formation, and induces gross morphological changes in MRSA cells without compromising the growth rate. MRSA is resistant to oxacillin because of the presence of penicillin-binding protein 2a (PBP2a), which allows peptidoglycan synthesis to continue after oxacillin-mediated acylation of native PBPs. We show that ECg binds predominantly to the cytoplasmic membrane (CM), initially decreasing the fluidity of the bilayer, and induces changes in gene expression indicative of an attempt to preserve and repair a compromised cell wall. On further incubation, the CM is reorganized; the amount of lysylphosphatidylglycerol is markedly reduced, with a concomitant increase in phosphatidylglycerol, and the proportion of branched chain fatty acids increases, resulting in a more fluid structure. We found no evidence that ECg modulates the enzymatic activity of PBP2a through direct binding to the protein but determined that PBP2 is delocalized from the FtsZ-anchored cell wall biosynthetic machinery at the septal division site following intercalation into the CM. We argue that many features of the ECg-induced phenotype can be explained by changes in the fluid dynamics of the CM. 相似文献