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991.
992.
Alda M Luciano JV Andrés E Serrano-Blanco A Rodero B del Hoyo YL Roca M Moreno S Magallón R García-Campayo J 《Arthritis research & therapy》2011,13(5):R173
Introduction
No randomised, controlled trials have been conducted to date on the efficacy of psychological and pharmacological treatments of pain catastrophising (PC) in patients with fibromyalgia. Our aim in this study was to assess the effectiveness of cognitive-behaviour therapy (CBT) and the recommended pharmacological treatment (RPT) compared with treatment as usual (TAU) at the primary care level for the treatment of PC in fibromyalgia patients. 相似文献993.
Melissa K. Wilson Alison B. Lane Bibiana F. Law William G. Miller Lynn A. Joens Michael E. Konkel Bryan A. White 《Microbial ecology》2009,58(4):843-855
Campylobacter jejuni is one of the leading bacterial causes of food-borne illness in the USA. Molecular typing methods are often used in food
safety for identifying sources of infection and pathways of transmission. Moreover, the identification of genetically related
isolates (i.e., clades) may facilitate the development of intervention strategies for control and prevention of food-borne
diseases. We analyzed the pan genome (i.e., core and variable genes) of 63 C. jejuni isolates recovered from chickens raised in conventional, organic, and free-range poultry flocks to gain insight into the
genetic diversity of C. jejuni isolates recovered from different environments. We assessed the discriminatory power of three genotyping methods [i.e., pulsed-field
gel electrophoresis (PFGE), multilocus sequence typing (MLST), and repetitive extragenic palindromic polymerase chain reaction
(rep-PCR)]. The rep-PCR fingerprint was generated by determining the presence of repetitive sequences that are interspersed throughout
the genome via repetitive extragenic palindromic PCR, enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR),
and BOX element PCR (BOX-PCR) and combining the data to form a composite fingerprint. The genetic fingerprints were subjected
to computer-assisted pattern analysis. Comparison of the three genotypic methods revealed that repREB-PCR showed greater discriminatory
power than PFGE and MLST. ERIC-PCR and BOX-PCR yielded the highest number of PCR products and greatest reproducibility. Regardless
of the genotyping method, C. jejuni isolates recovered from chickens reared in conventional, organic, and free-range environments all exhibit a high level of
genotypic diversity. 相似文献
994.
Prado GN Mierke DF LeBlanc T Manseau M Taylor L Yu J Zhang R Pal-Ghosh R Polgar P 《Journal of cellular biochemistry》2001,83(3):435-447
In past reports we illustrated the importance of Y131, Y322, and T137 within the intracellular (IC) face of the rat bradykinin B2 receptor (rBKB2R) for signal transduction and receptor maintenance (Prado et al. [1997] J. Biol. Chem. 272:14638-14642; Prado et al. [1998] J. Biol. Chem. 273:33548-33555). In this report, we mutate the remaining hydroxyl possessing residues located within the rBKB2R IC region. Exchange of S139A (IC2) or T239V (IC3) did not affect BK activated phosphatidylinositol (PI) turnover or receptor internalization. Chimeric exchange of the last 34 amino acids of BKB2R C-terminus with the corresponding 34 amino acids of the rat angiotensin II AT1a receptor (rAT1aR), both containing an S/T cluster, resulted in a mutant with normal endocytosis and BK activated PI turnover. A more selective chimera of these S/T clusters, with an exchange of BKB2R (333-351) with a rAT1aR fragment (326-342), resulted in a receptor with a retarded internalization but a normal BK activated PI turnover. Subsequent mutation of rBKB2R T344V showed little change in receptor uptake but a pronounced loss of BK activated PI turnover. The mutation of S335A, S341A, S348A, and S350A resulted in very poor receptor internalization and loss of activated PI turnover. Closer examination of this serine cluster illustrated that the replacement of S348A led to poor internalization; whereas the retention of S348 and mutation of S341A resulted in a receptor with a much greater internalization than WT. These and other results suggest that the presence of S348 promotes internalization while the presence of S341 dampens it. Conversely, S341 and S350 proved important for receptor signaling. In sum, our results illustrate that the distal C-terminus including its S/T cluster is important for both rBKB2R internalization and signal transduction. Individual S/T residues within this cluster appear involved in either signal transmission or receptor uptake capacity. However, replacement of the entire distal tail region with the corresponding rAT1aR sequence, also containing an S/T cluster, enables the BKB2R/AT1aR chimera to act in a very similar manner to wild type rBKB2R. 相似文献
995.
Soil temperature is known to affect plant growth and productivity. In this study we found that low root-zone temperature (LRT) inhibited the growth of apple (Malus baccata Borkh.) seedlings. To elucidate the molecular mechanism of LRT response, we performed comparative proteome analysis of the apple roots under LRT for 6 days. Total proteins of roots were extracted and separated by two-dimensional gel electrophoresis (2-DE) and 29 differentially accumulated proteins were successfully identified by MALDI-TOF/TOF mass spectrometry. They were involved in protein transport/processing/degradation (21%), glycometabolism (20%), response to stress (14%), oxidoreductase activity (14%), protein binding (7%), RNA metabolism (7%), amino acid biosynthesis (3%) and others (14%). The results revealed that LRT inhibited glycometabolism and RNA metabolism. The up-regulated proteins which were associated with oxidoreductase activity, protein metabolism and defense response, might be involved in protection mechanisms against LRT stress in the apple seedlings. Subsequently, 8 proteins were selected for the mRNA quantification analysis, and we found 6 of them were consistently regulated between protein and mRNA levels. In addition, the enzyme activities in ascorbate–glutathione (AsA–GSH) cycle were determined, and APX activity was increased and GR activity was decreased under LRT, in consistent with the protein levels. This study provides new insights into the molecular mechanisms of M. baccata in responding to LRT. 相似文献
996.
Seong-In Na Yeong Ouk Kim Seok-Hwan Yoon Sung-min Ha Inwoo Baek Jongsik Chun 《Journal of microbiology (Seoul, Korea)》2018,56(4):280-285
Genome-based phylogeny plays a central role in the future taxonomy and phylogenetics of Bacteria and Archaea by replacing 16S rRNA gene phylogeny. The concatenated core gene alignments are frequently used for such a purpose. The bacterial core genes are defined as single-copy, homologous genes that are present in most of the known bacterial species. There have been several studies describing such a gene set, but the number of species considered was rather small. Here we present the up-to-date bacterial core gene set, named UBCG, and software suites to accommodate necessary steps to generate and evaluate phylogenetic trees. The method was successfully used to infer phylogenomic relationship of Escherichia and related taxa and can be used for the set of genomes at any taxonomic ranks of Bacteria. The UBCG pipeline and file viewer are freely available at https://www.ezbiocloud.net/tools/ubcg and https://www.ezbiocloud.net/tools/ubcg_viewer, respectively. 相似文献
997.
Duangrudee Cherdwongcharoensuk Maria João Oliveira Artur Perez Águas 《Biological trace element research》2010,136(2):197-203
The in vivo dynamics of selenium (Se) and mercury (Hg) interaction was studied in mouse tissues using direct visualization
of individual Se, Hg, and SeHg particles on the surface of circulating erythrocytes. This high-resolution detection of Se
and Hg was obtained by scanning electron microscopy coupled to X-ray microanalysis. BALB/c mice were injected in the peritoneal
cavity with Se and Hg salts, and the animals were sacrificed 3 min after the Hg injection. Only a minority (9%) of the metal
dots seen on mouse liver erythrocytes were SeHg complexes when Se and Hg salts were mixed together before injection. In contrast,
the majority (73%) of metal dots on liver erythrocytes were SeHg complexes if Se was injected at least 5 min before Hg injection.
All metal dots on liver erythrocytes were of SeHg complexes if Se was injected 9 or 12 min before the Hg injection. We conclude
that the formation of stable in vivo SeHg complexes requires preliminary interaction of Se with a putative serum factor before
complexes between Se and Hg are formed and are bound to the erythrocyte cell surface. 相似文献
998.
Lee Taylor Adrian W. Midgley Bryna Chrismas Angela R. Hilman Leigh A. Madden Rebecca V. Vince Lars R. McNaughton 《Amino acids》2011,40(2):393-401
Heat shock protein 72 (HSP72) performs vital roles within the body at rest and during periods of stress. In vitro, research
demonstrates HSP72 induction in response to hypoxia. Recently, in vivo, an acute hypoxic exposure (75 min at 2,980 m) was
sufficient to induce significant increases in monocyte expressed HSP72 (mHSP72) and a marker of oxidative stress in healthy human subjects. The purpose of the current study was to identify the impact
of 10 consecutive days of hypoxic exposures (75 min at 2,980 m) on mHSP72 and erythropoietin (EPO) expression, markers of oxidative stress, and maximal oxygen consumption in graded incremental aerobic
exercise. Eight male subjects were exposed to daily normobaric hypoxic exposures for 75 min at 2,980 m for 10 consecutive
days, commencing and ceasing at 0930 and 1045, respectively. This stressor was sufficient to induce significant increases
in mHSP72, which was significantly elevated from day 2 of the hypoxic exposures until 48 h post-final exposure. Notably, this increase
had an initial rapid (30% day on day compared to baseline) and final slow phase (16% day on day compared to baseline) of expression.
The authors postulate that 7-day hypoxic exposure in this manner would be sufficient to induce near maximum hypoxia-mediated
basal mHSP72 expression. Elevated levels of mHSP72 are associated with acquired thermotolerance and provide cross tolerance to non-related stressors in vivo, the protocol used
here may provide a useful tool for elevating mHSP72 in vivo. Aside from these major findings, significant transient daily elevations were seen in a marker of oxidative stress,
alongside sustained increases in EPO expression. However, no physiologically significant changes were seen in maximal oxygen
consumption or time to exhaustion. 相似文献
999.
氯化钠密度梯度离心法制备用于显微注射的外源DNA片段 总被引:2,自引:0,他引:2
DNA显微注射是生产转基因动物最可靠和最常使用的一种方法,外源DNA的纯度对显微注射的成功起着至关重要的作用。本文介绍用氯化钠密度梯度离心的方法制备用于显微注射的外源DNA片段。与传统的琼脂糖凝胶回收的方法相比较,用此方法制备的外源DNA片段对小鼠受精卵进行显微注射后,受卵体母鼠的胚胎存活率,以及子代小鼠的外源基因整合率均有明显的提高。这一方法可为进一步提高转基因动物的成功率,提供方法学上的参考。
Abstract:DNA microinjection is the most popular and reliable method of producing transgenic animals.The purity of foreign DNA plays an important role for the success of microinjection.In this study,we introduced the use of sodium chloride step gradients in fractionating foreign DNA fragment for microinjection.The data demonstrated that,compared with the conventional agarose gel extraction method,NaCl purification scheme of toreign DNA could improve the treated embryo survival and foreign DNA intergration rate markedly. 相似文献
1000.