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2.
Cytokine production in a model of wound healing: the appearance of MIP-1, MIP-2, cachectin/TNF and IL-1 总被引:9,自引:1,他引:8
T J Fahey B Sherry K J Tracey S van Deventer W G Jones J P Minei S Morgello G T Shires A Cerami 《Cytokine》1990,2(2):92-99
Macrophages are essential for normal wound repair and many of their effects on healing wounds are likely to be mediated by the secretion of cytokines. This study examines the appearance of messenger RNA (mRNA) for cachectin/tumor necrosis factor (TNF), IL 1, and macrophage inflammatory proteins 1 and 2 (MIP-1 and MIP-2), as well as the mature peptides, in a model of wound healing using wound chambers. RNA for all four cytokines can be detected in wound inflammatory cells by polymerase chain reaction amplification throughout the first 7 days. Cachectin/TNF and IL 1 protein levels peaked on the first day after wound chamber implantation, and MIP-1 and MIP-2 were detected only on day 3. The data suggest that these cytokines participate in the early inflammatory response to wounding. 相似文献
3.
Maria C Romay Mark J Millard Jeffrey C Glaubitz Jason A Peiffer Kelly L Swarts Terry M Casstevens Robert J Elshire Charlotte B Acharya Sharon E Mitchell Sherry A Flint-Garcia Michael D McMullen James B Holland Edward S Buckler Candice A Gardner 《Genome biology》2013,14(6):R55
Background
Genotyping by sequencing, a new low-cost, high-throughput sequencing technology was used to genotype 2,815 maize inbred accessions, preserved mostly at the National Plant Germplasm System in the USA. The collection includes inbred lines from breeding programs all over the world.Results
The method produced 681,257 single-nucleotide polymorphism (SNP) markers distributed across the entire genome, with the ability to detect rare alleles at high confidence levels. More than half of the SNPs in the collection are rare. Although most rare alleles have been incorporated into public temperate breeding programs, only a modest amount of the available diversity is present in the commercial germplasm. Analysis of genetic distances shows population stratification, including a small number of large clusters centered on key lines. Nevertheless, an average fixation index of 0.06 indicates moderate differentiation between the three major maize subpopulations. Linkage disequilibrium (LD) decays very rapidly, but the extent of LD is highly dependent on the particular group of germplasm and region of the genome. The utility of these data for performing genome-wide association studies was tested with two simply inherited traits and one complex trait. We identified trait associations at SNPs very close to known candidate genes for kernel color, sweet corn, and flowering time; however, results suggest that more SNPs are needed to better explore the genetic architecture of complex traits.Conclusions
The genotypic information described here allows this publicly available panel to be exploited by researchers facing the challenges of sustainable agriculture through better knowledge of the nature of genetic diversity. 相似文献4.
Liming Yan Yiqi Luo Rebecca A. Sherry Jesse E. Bell Xuhui Zhou Jianyang Xia 《Global Change Biology Bioenergy》2014,6(5):556-565
The efficiency of a terrestrial ecosystem to use rainfall in production is critical in regulating the ecological functions of the earth system under global change. However, it remains unclear how rain use efficiency (RUE) will be altered by changes in climate and human activities such as biofuel harvest. In this study, we used RUE data from a long‐term experiment in a tallgrass prairie to analyze the effects of warming and biofuel harvest (clipping). From 2000 to 2011, experimental warming enhanced RUE in most years, with larger positive effects in normal and wet than dry hydrological years. Clipping decreased RUE in dry and normal hydrological years, but had no impact on RUE in wet years. The observed RUE responses resulted from treatment‐induced changes in both biologically ineffective (i.e., runoff and soil evaporation) and effective (i.e., transpiration) parts of precipitation. For example, litter cover was increased in warming plots, but reduced by clipping, leading to negative and positive effects on runoff and soil evaporation, respectively. The dominance of C4 species, which usually have higher water use efficiency than C3 species, was enhanced by warming, but reduced by clipping. Moreover, RUE was positively correlated with ratios of rainfall in the late growing season (June–August), when the growth of C4 plants was most active, relative to that in the other seasons. Our results indicate that RUE is positively influenced by climate warming, but negatively affected by biofuel harvest in tallgrass prairie of the Great Plains. These findings highlight the important roles of plant community structure and temporal distribution of precipitation in regulating ecosystem RUE. 相似文献
5.
Sherry C. Wen Sharon J. Tollefson Monika Johnson Pavlo Gilchuk Kelli L. Boyd Bryan Shepherd Sebastian Joyce John V. Williams 《Journal of virology》2014,88(18):10963-10969
Human metapneumovirus (HMPV) is a major cause of respiratory disease. The role of NK cells in protection against HMPV is unclear. We show that while HMPV-infected C57BL/6 mice had higher numbers of functional lung NK cells than mock-treated mice, comparing NK cell-depleted and control mice did not reveal differences in lung viral titers, histopathology, cytokine levels, or T cell numbers or function. These data indicate that NK cells are not required for host control of HMPV. 相似文献
6.
Fleming SD Monestier M Tsokos GC 《Journal of immunology (Baltimore, Md. : 1950)》2004,173(6):4230-4235
Natural Abs have been implicated in initiating mesenteric ischemia/reperfusion (I/R)-induced tissue injury. Autoantibodies have affinity and self-Ag recognition patterns similar to natural Abs. We considered that autoimmunity-prone mice that express high titers of autoantibodies should have enhanced I/R-induced injury. Five-month-old B6.MRL/lpr mice displayed accelerated and enhanced intestinal I/R-induced damage compared with 2-mo-old B6.MRL/lpr and age-matched C57BL/6 mice. Similarly, older autoimmune mice had accelerated remote organ (lung) damage. Infusion of serum IgG derived from 5-mo-old but not 2-mo-old B6.MRL/lpr into I/R resistant Rag-1-/- mice rendered them susceptible to local and remote organ injury. Injection of monoclonal IgG anti-DNA and anti-histone Abs into Rag-1-/- mice effectively reconstituted tissue injury. These data show that like natural Abs, autoantibodies, such as anti-dsDNA and anti-histone Abs, can instigate I/R injury and suggest that they are involved in the development of tissue damage in patients with systemic lupus erythematosus. 相似文献
7.
Pagoto SL Schneider KL Oleski JL Luciani JM Bodenlos JS Whited MC 《Obesity (Silver Spring, Md.)》2012,20(6):1234-1239
The prevalence of obesity is similar for men (32.2%) and women (35.5%). It has been assumed that lifestyle weight loss interventions have been developed and tested in predominately female samples, but this has not been systematically investigated. The aim of this review was to investigate total and ethnic male inclusion in randomized controlled trials of lifestyle interventions. PUBMED, MEDLINE, and PSYCHINFO were searched for randomized controlled trials of lifestyle weight loss interventions (N = 244 studies with a total of 95,207 participants) published in the last 10 years (1999-2009). A trial must be in English, included weight loss as an outcome, and tested a dietary, exercise, and/or other behavioral intervention for weight loss. Results revealed samples were on average 27% male vs. 73% female (P < 0.001). Trials recruiting a diseased sample included a larger proportion of males than those not targeting a disease (35% vs. 21%; P < 0.001). About 32% of trials used exclusively female samples, whereas only 5% used exclusively male samples (P < 0.001). No studies in the past 10 years specifically targeted minority males. Ethnic males identified composed 1.8% of total participants in US studies. Only 24% of studies that underrepresented males provided a reason. Males, especially ethnic males, are underrepresented in lifestyle weight loss trials. 相似文献
8.
Dadsetan S Bak LK Sørensen M Keiding S Vilstrup H Ott P Leke R Schousboe A Waagepetersen HS 《Neurochemistry international》2011,59(4):482-488
It has been previously demonstrated that ammonia exposure of neurons and astrocytes in co-culture leads to net synthesis not only of glutamine but also of alanine. The latter process involves the concerted action of glutamate dehydrogenase (GDH) and alanine aminotransferase (ALAT). In the present study it was investigated if the glutamine synthetase (GS) inhibitor methionine sulfoximine (MSO) would enhance alanine synthesis by blocking the GS-dependent ammonia scavenging process. Hence, co-cultures of neurons and astrocytes were incubated for 2.5 h with [U-13C]glucose to monitor de novo synthesis of alanine and glutamine in the absence and presence of 5.0 mM NH4Cl and 10 mM MSO. Ammonia exposure led to increased incorporation of label but not to a significant increase in the amount of these amino acids. However, in the presence of MSO, glutamine synthesis was blocked and synthesis of alanine increased leading to an elevated content intra- as well as extracellularly of this amino acid. Treatment with MSO led to a dramatic decrease in glutamine content and increased the intracellular contents of glutamate and aspartate. The large increase in alanine during exposure to MSO underlines the importance of the GDH and ALAT biosynthetic pathway for ammonia fixation, and it points to the use of a GS inhibitor to ameliorate the brain toxicity and edema induced by hyperammonemia, events likely related to glutamine synthesis. 相似文献
9.
Júlia R. de Rezende Thomas B. P. Oldenburg Tetyana Korin William D. L. Richardson Milovan Fustic Carolyn M. Aitken Bernard F. J. Bowler Angela Sherry Alexander Grigoryan Gerrit Voordouw Stephen R. Larter Ian M. Head Casey R. J. Hubert 《Environmental microbiology》2020,22(8):3049-3065
Most of the oil in low temperature, non-uplifted reservoirs is biodegraded due to millions of years of microbial activity, including via methanogenesis from crude oil. To evaluate stimulating additional methanogenesis in already heavily biodegraded oil reservoirs, oil sands samples were amended with nutrients and electron acceptors, but oil sands bitumen was the only organic substrate. Methane production was monitored for over 3000 days. Methanogenesis was observed in duplicate microcosms that were unamended, amended with sulfate or that were initially oxic, however methanogenesis was not observed in nitrate-amended controls. The highest rate of methane production was 0.15 μmol CH4 g−1 oil d−1, orders of magnitude lower than other reports of methanogenesis from lighter crude oils. Methanogenic Archaea and several potential syntrophic bacterial partners were detected following the incubations. GC–MS and FTICR–MS revealed no significant bitumen alteration for any specific compound or compound class, suggesting that the very slow methanogenesis observed was coupled to bitumen biodegradation in an unspecific manner. After 3000 days, methanogenic communities were amended with benzoate resulting in methanogenesis rates that were 110-fold greater. This suggests that oil-to-methane conversion is limited by the recalcitrant nature of oil sands bitumen, not the microbial communities resident in heavy oil reservoirs. 相似文献
10.
Suen DF Wu SS Chang HC Dhugga KS Huang AH 《The Journal of biological chemistry》2003,278(44):43672-43681
The surface of a pollen grain consists of an outermost coat and an underlying wall. In maize (Zea mays L.), the pollen coat contains two major proteins derived from the adjacent tapetum cells in the anthers. One of the proteins is a 35-kDa endoxylanase (Wu, S. S. H., Suen, D. F., Chang, H. C., and Huang, A. H. C. (2002) J. Biol. Chem. 277, 49055-49064). The other protein of 70 kDa was purified to homogeneity and shown to be a beta-glucanase. Its gene sequence and the developmental pattern of its mRNA differ from those of the known beta-glucanases that hydrolyze the callose wall of the microspore tetrad. Mature pollen placed in a liquid medium released about nine major proteins. These proteins were partially sequenced and identified via GenBank trade mark data bases, and some had not been previously reported to be in pollen. They appear to have wall-loosening, structural, and enzymatic functions. A novel pollen wall-bound protein of 17 kDa has a unique pattern of cysteine distribution in its sequence (six tandem repeats of CX3CX10-15) that could chelate cations and form signal-receiving finger motifs. These pollen-released proteins were synthesized in the pollen interior, and their mRNA increased during pollen maturation and germination. They were localized mainly in the pollen tube wall. The pollen shell was isolated and found to contain no detectable proteins. We suggest that the pollen-coat beta-glucanase and xylanase hydrolyze the stigma wall for pollen tube entry and that the pollen secrete proteins to loosen or become new wall constituents of the tube and to break the wall of the transmitting track for tube advance. 相似文献