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81.
82.
Eakin CM Morgan JA Heron SF Smith TB Liu G Alvarez-Filip L Baca B Bartels E Bastidas C Bouchon C Brandt M Bruckner AW Bunkley-Williams L Cameron A Causey BD Chiappone M Christensen TR Crabbe MJ Day O de la Guardia E Díaz-Pulido G DiResta D Gil-Agudelo DL Gilliam DS Ginsburg RN Gore S Guzmán HM Hendee JC Hernández-Delgado EA Husain E Jeffrey CF Jones RJ Jordán-Dahlgren E Kaufman LS Kline DI Kramer PA Lang JC Lirman D Mallela J Manfrino C Maréchal JP Marks K Mihaly J Miller WJ Mueller EM 《PloS one》2010,5(11):e13969
Background
The rising temperature of the world''s oceans has become a major threat to coral reefs globally as the severity and frequency of mass coral bleaching and mortality events increase. In 2005, high ocean temperatures in the tropical Atlantic and Caribbean resulted in the most severe bleaching event ever recorded in the basin.Methodology/Principal Findings
Satellite-based tools provided warnings for coral reef managers and scientists, guiding both the timing and location of researchers'' field observations as anomalously warm conditions developed and spread across the greater Caribbean region from June to October 2005. Field surveys of bleaching and mortality exceeded prior efforts in detail and extent, and provided a new standard for documenting the effects of bleaching and for testing nowcast and forecast products. Collaborators from 22 countries undertook the most comprehensive documentation of basin-scale bleaching to date and found that over 80% of corals bleached and over 40% died at many sites. The most severe bleaching coincided with waters nearest a western Atlantic warm pool that was centered off the northern end of the Lesser Antilles.Conclusions/Significance
Thermal stress during the 2005 event exceeded any observed from the Caribbean in the prior 20 years, and regionally-averaged temperatures were the warmest in over 150 years. Comparison of satellite data against field surveys demonstrated a significant predictive relationship between accumulated heat stress (measured using NOAA Coral Reef Watch''s Degree Heating Weeks) and bleaching intensity. This severe, widespread bleaching and mortality will undoubtedly have long-term consequences for reef ecosystems and suggests a troubled future for tropical marine ecosystems under a warming climate. 相似文献83.
84.
Brock Arivett Mary Farone Ranjith Masiragani Andrew Burden Shelby Judge Adedoyin Osinloye Claudia Minici Massimo Degano Matthew Robinson Paul Kline 《Biochimica et Biophysica Acta - Proteins and Proteomics》2014,1844(3):656-662
A non-specific nucleoside hydrolase from Escherichia coli (RihC) has been cloned, overexpressed, and purified to greater than 95% homogeneity. Size exclusion chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis show that the protein exists as a homodimer. The enzyme showed significant activity against the standard ribonucleosides with uridine, xanthosine, and inosine having the greatest activity. The Michaelis constants were relatively constant for uridine, cytidine, inosine, adenosine, xanthosine, and ribothymidine at approximately 480 μM. No activity was exhibited against 2′-OH and 3′-OH deoxynucleosides. Nucleosides in which additional groups have been added to the exocyclic N6 amino group also exhibited no activity. Nucleosides lacking the 5′-OH group or with the 2′-OH group in the arabino configuration exhibited greatly reduced activity. Purine nucleosides and pyrimidine nucleosides in which the N7 or N3 nitrogens respectively were replaced with carbon also had no activity. 相似文献
85.
Rachel Knevel Diederik PC de Rooy Tore Saxne Elisabet Lindqvist Martha K Leijsma Nina A Daha Bobby PC Koeleman Roula Tsonaka Jeanine J Houwing-Duistermaat Joris JM Schonkeren Rene EM Toes Tom WJ Huizinga Elisabeth Brouwer Anthony G Wilson Annette HM van der Helm-van Mil 《Arthritis research & therapy》2014,16(3):R108
Introduction
Progression of joint destruction in rheumatoid arthritis (RA) is partly heritably; 45 to 58% of the variance in joint destruction is estimated to be explained by genetic factors. The binding of RANKL (Receptor Activator for Nuclear Factor κ B Ligand) to RANK results in the activation of TRAF6 (tumor necrosis factor (TNF) receptor associated factor-6), and osteoclast formation ultimately leading to enhanced bone resorption. This bone resorption is inhibited by osteoprotegerin (OPG) which prevents RANKL-RANK interactions. The OPG/RANK/RANKL/TRAF6 pathway plays an important role in bone remodeling. Therefore, we investigated whether genetic variants in OPG, RANK, RANKL and TRAF6 are associated with the rate of joint destruction in RA.Methods
1,418 patients with 4,885 X-rays of hands and feet derived from four independent data-sets were studied. In each data-set the relative increase of the progression rate per year in the presence of a genotype was assessed. First, explorative analyses were performed on 600 RA-patients from Leiden. 109 SNPs, tagging OPG, RANK, RANKL and TRAF6, were tested. Single nucleotide polymorphisms (SNPs) significantly associated in phase-1 were genotyped in data-sets from Groningen (Netherlands), Sheffield (United Kingdom) and Lund (Switzerland). Data were summarized in an inverse weighted variance meta-analysis. Bonferonni correction for multiple testing was applied.Results
We found that 33 SNPs were significantly associated with the rate of joint destruction in phase-1. In phase-2, six SNPs in OPG and four SNPs in RANK were associated with progression of joint destruction with P-value <0.05. In the meta-analyses of all four data-sets, RA-patients with the minor allele of OPG-rs1485305 expressed higher rates of joint destruction compared to patients without these risk variants (P = 2.35x10−4). This variant was also significant after Bonferroni correction.Conclusions
These results indicate that a genetic variant in OPG is associated with a more severe rate of joint destruction in RA. 相似文献86.
The determinants of conversational dominance are not well understood. We used videotaped triadic interactions among unacquainted same-sex American college students to test predictions drawn from the theoretical distinction between dominance and prestige as modes of human status competition. Specifically, we investigated the effects of physical formidability, facial attractiveness, social status, and self-reported subclinical psychopathy on quantitative (proportion of words produced), participatory (interruptions produced and sustained), and sequential (topic control) dominance. No measure of physical formidability or attractiveness was associated with any form of conversational dominance, suggesting that the characteristics of our study population or experimental frame may have moderated their role in dominance dynamics. Primary psychopathy was positively associated with quantitative dominance and (marginally) overall triad talkativeness, and negatively associated (in men) with affect word use, whereas secondary psychopathy was unrelated to conversational dominance. The two psychopathy factors had significant opposing effects on quantitative dominance in a multivariate model. These latter findings suggest that glibness in primary psychopathy may function to elicit exploitable information from others in a relationally mobile society. 相似文献
87.
A cytotoxic leachable compound from single‐use bioprocess equipment that causes poor cell growth performance 下载免费PDF全文
Matthew Hammond Liliana Marghitoiu Hans Lee Lourdes Perez Gary Rogers Yasser Nashed‐Samuel Heather Nunn Sally Kline 《Biotechnology progress》2014,30(2):332-337
A current trend in the production of biopharmaceuticals is the replacement of fixed stainless steel fluid‐handling units with disposable plastic bags. Such single‐use systems (SUS) offer numerous advantages, but also introduce a new set of materials into the production process and consequently expose biomanufacturers to a new set of risks related to those materials, not to mention reliance on an entirely new supply chain. In the course of developing and conducting a cell‐growth‐based test for suitability of disposable plastic components destined for use in cell culture operations, we discovered that the cytotoxic compound bis(2,4‐di‐tert‐butylphenyl)phosphate (bDtBPP) leaches out of certain bags and into cell culture media in concentrations that are deleterious to cell growth. Specifically, media held in certain bags for several days at 37°C was found to contain bDtBPP, and use of those held‐media samples in cell growth experiments provides data that overlap neatly with cell growth experiments using media spiked directly with bDtBPP, proving that bDtBPP leaching is responsible for the reduced growth attributable to those SUS bags. Overall, this issue represents a risk to the production of biopharmaceuticals in SUS, a risk that must be managed by diligent collaboration among companies along the entire supply chain for SUS components. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:332–337, 2014 相似文献
88.
Jamil M Neto Marina GM Viturino Galina Ananina Flvia F Bajano Sueli M da S Costa Alicia B Roque Gessica FS Borges Raissa Franchi Priscila HH Rim Flvio M Medina Fernando F Costa Mnica B de Melo Jos PC de Vasconcellos 《Experimental biology and medicine (Maywood, N.J.)》2021,246(21):2290
This study aimed to investigate the association among genetic variants of the complement pathway CFB R32Q (rs641153), C3 R102G (rs2230199), and CFH (rs1410996) with age-related macular degeneration (AMD) in a sample of the Brazilian population. In a case-control study, 484 AMD patients were classified according to the clinical age-related maculopathy grading system (CARMS) and compared to 479 unrelated controls. The genetic variants rs1410996 of complement H (CFH), rs641153 of complement factor B (CFB), and rs2230199 of complement 3 (C3) were evaluated through polymerase chain reaction (PCR) and direct sequencing. The associations between single nucleotide polymorphisms (SNPs) and AMD, adjusted by age, were assessed by using logistic regression models. A statistically significant association was observed between AMD risk and rs2230199 variant with an OR of 2.01 (P = 0.0002) for CG individuals compared to CC individuals. Regarding the comparison of advanced AMD versus the control group, the OR was 2.12 (P = 0.0036) for GG versus AA genotypes for rs1410996 variant. Similarly, the OR for rs2230199 polymorphism was 2.3034 (P = 5.47e-05) when comparing CG individuals to CC carriers. In contrast, the rs641153 variant showed a significant protective effect against advanced AMD for GA versus GG genotype (OR = 0.4406; P = 0.0019). When comparing wet AMD versus controls, a significant association was detected for rs1410996 variant (OR = 2.16; P = 0.0039) comparing carriers of the homozygous GG versus AA genotype, as well as in the comparisons of GG (OR = 3.0713; P = 0.0046) and CG genotypes (OR = 2.2249; P = 0.0002) versus CC genotype for rs2230199 variant, respectively. The rs641153 variant granted a significant protective effect against wet AMD for GA versus GG genotypes (OR = 0.4601; P = 0.0044). Our study confirmed the risk association between rs2230199 and rs1410996 variants and AMD, and the protective role against AMD for rs641153 variant. 相似文献
89.
Cecilia PC Soh Alastair SR Donald James Feeney Walter TJ Morgan Winifred M Watkins 《Glycoconjugate journal》1989,6(3):319-332
The tetrasaccharides GalNAcß1-4[NeuAc2-3]Galß1-4Glc and GalNAcß1-4[NeuAc2-3]Galß1-4GlcNAc were synthesised by enzymic transfer of GalNAc from UDP-GalNAc to 3-sialyllactose (NeuAc2-3Galß1-4Glc) and 3-sialyl-N-acetyllactosamine (NeuAc2-3Galß1-4GlcNAc). The structures of the products were established by methylation and1H-500 MHz NMR spectroscopy. In Sda serological tests the product formed with 3-sialyl-N-acetyllactosamine was highly active whereas that formed with 3-sialyllactose had only weak activity. 相似文献
90.
Calcitonin gene related peptide has been shown to relax vascular and intestinal smooth muscle. This study examines the effects of calcitonin gene related peptide on cholecystokinin-induced contraction of guinea pig gallbladder strips in vitro. Calcitonin gene related peptide was found to cause a dose-dependent relaxation of cholecystokinin-induced tension, which was blocked by the calcitonin gene related peptide receptor antagonist human calcitonin gene related peptide. Previous studies demonstrated that calcitonin gene related peptide acted directly on guinea pig gallbladder smooth muscle to inhibit acetylcholine- or KCl-induced contraction. The present results further confirm that calcitonin gene related peptide acts directly on the smooth muscle. In addition, the use of L-NG-nitroarginine methyl ester, glibenclamide, and other agents strongly suggests that calcitonin gene related peptide also acts by way of the nonadrenergic noncholinergic nervous system, to induce the relaxation of cholecystokinin-induced contraction observed in the guinea pig gallbladder strips. 相似文献