Background: Human C-reactive protein (CRP) is the classical acute phase reactant, the circulating concentration of which rises rapidly and extensively in a cytokine-mediated response to tissue ...injury, infection and inflammation. Serum CRP values are routinely measured, empirically, to detect and monitor many human diseases. However, CRP is likely to have important host defence, scavenging and metabolic functions through its capacity for calcium-dependent binding to exogenous and autologous molecules containing phosphocholine (PC) and then activating the classical complement pathway. CRP may also have pathogenic effects and the recent discovery of a prognostic association between increased CRP production and coronary atherothrombotic events is of particular interest.
Results: The X-ray structures of fully calcified C-reactive protein, in the presence and absence of bound PC, reveal that although the subunit
β-sheet jellyroll fold is very similar to that of the homologous pentameric protein serum amyloid P component, each subunit is tipped towards the fivefold axis. PC is bound in a shallow surface pocket on each subunit, interacting with the two protein-bound calcium ions via the phosphate group and with Glu81 via the choline moiety. There is also an unexpected hydrophobic pocket adjacent to the ligand.
Conclusions: The structure shows how large ligands containing PC may be bound by CRP via a phosphate oxygen that projects away from the surface of the protein. Multipoint attachment of one planar face of the CRP molecule to a PC-bearing surface would leave available, on the opposite exposed face, the recognition sites for C1q, which have been identified by mutagenesis. This would enable CRP to target physiologically and/or pathologically significant complement activation. The hydrophobic pocket adjacent to bound PC invites the design of inhibitors of CRP binding that may have therapeutic relevance to the possible role of CRP in atherothrombotic events.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Bringing effective, research-based literacy interventions into the classroom is challenging, especially given the cultural and linguistic diversity of today's classrooms. We examined the promise of ...Assessment-to-Instruction (A2i) technology redesigned to be used at scale to support teachers' implementation of the individualized student instruction (ISI) intervention from kindergarten through third grade. In seven randomized controlled trials, A2i and ISI have demonstrated efficacy. However, the research version of A2i was not scalable. To bring A2i to scale in schools serving linguistically diverse students, we carried out the current study across two phases. This study represents both an exploration of what it takes to bring an educational intervention to scale (Phase 1) and a quasi-experiment on the literacy outcomes of learners whose teachers used the technology (Phase 2). We integrated assessments of vocabulary, word decoding, and reading comprehension; revised the A2i algorithms to account for the constellation of skills English learners (ELs) bring to the classroom; updated the user interfaces and added new graphic features; and improved bandwidth and stability of the technology. Findings were mixed, including several nonsignificant results, a marginally significant intent-to-treat effect on word reading in kindergarten and first grade for English monolingual students and ELs, and one significant interaction effect, which suggested ELs and students with less developed reading skills in second and third grade benefited most from the intervention. With some caution, we conclude that A2i demonstrates potential to be used at scale and promise of effectiveness for improving code-focused skills for diverse learners.
Educational Impact and Implications StatementIn this study, we outline the process of bringing Assessment-to-Instruction (A2i) technology to scale within kindergarten through third grade classrooms serving linguistically diverse learners. We carried out this research within two interactive phases. Within Phase 1, we worked closely with our school partners to guide the revision of A2i technology to use at scale. In Phase 2, we conducted a quasi-experiment on the literacy outcomes of learners whose teachers used A2i. Overall, our newly designed A2i technology shows promise to use at scale with kindergarten and first grade monolingual students and English learners. Limitations, implications, and future directions are discussed.
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CEKLJ, FFLJ, NUK, ODKLJ, PEFLJ, UPUK
The interaction of momordin, a type 1 ribosome‐inactivating protein from Momordica charantia, with NADP+ and NADPH has been investigated by X‐ray diffraction analysis of complexes generated by ...co‐crystallization and crystal soaking. It is known that the proteins of this family readily cleave the adenine–ribose bond of adenosine and related nucleotides in the crystal, leaving the product, adenine, bound to the enzyme active site. Surprisingly, the nicotinamide–ribose bond of oxidized NADP+ is cleaved, leaving nicotinamide bound in the active site in the same position but in a slightly different orientation to that of the five‐membered ring of adenine. No binding or cleavage of NADPH was observed at pH 7.4 in these experiments. These observations are in accord with current views of the enzyme mechanism and may contribute to ongoing searches for effective inhibitors.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Non-syndromic craniosynostosis (CS) affects 1 in 2350 live births. Recent studies have shown that a significant fraction of cases are caused by de novo or rare transmitted mutations that promote ...premature osteoblast differentiation in cranial sutures. Rare heterozygous loss-of-function (LOF) mutations in
and
are highly enriched in patients with non-syndromic sagittal and coronal CS, respectively. Interestingly, both mutations show striking incomplete penetrance, suggesting a role for modifying alleles; in the case of
, a common variant near
drastically increases penetrance of sagittal CS. Here, we report a proband presenting with both sagittal and coronal craniosynostosis with the highly unusual recurrence of CS within two months of initial surgery, requiring a second operation to re-establish suture patency at six months of age. Exome sequencing revealed a rare transmitted frameshift mutation in
(p. 152 fs*27) inherited from an unaffected parent, absence of the common
risk variant, and a de novo frameshift mutation in
(p.E548fs*14).
and
independently inhibit transcriptional targets of BMP signaling. The findings are consistent with epistasis of these mutations, increasing penetrance and severity of CS in this proband. They also add to the list of composite phenotypes resulting from two Mendelian mutations, and support the utility of exome sequencing in atypical CS cases.
Melanoma is one of the most aggressive and lethal forms of skin cancer. Despite recent improvements in targeted therapies, many patients with advanced disease fail to achieve lasting tumor ...regression. Therefore, it is important to develop novel druggable targets that can be exploited to improve clinical outcome. Here, we studied the role of Casitas B-lineage lymphoma (c-CBL), an E3 ubiquitin ligase, in human melanoma. Employing quantitative real-time PCR and Western blot analysis in a panel of human melanoma cell lines (A375, G361, Hs-294T, SK-Mel-2, SK-Mel-28 and 451Lu), we found that c-CBL is strongly expressed in human melanoma cells at the mRNA and protein levels. Further, we determined c-CBL levels in clinical samples of melanomas and benign melanocytic nevi, using quantitative Nuance multispectral imaging. Compared to benign nevi, melanomas showed an overlapping range of c-CBL immunoreactivity. Small interfering RNA (siRNA)-mediated knockdown of c-CBL resulted in decreased proliferation, clonogenic survival and migration of melanoma cells. Furthermore, it also resulted in decreased cellular invasion in a 3D spheroid assay system. C-CBL and FAK are regulated by SRC, and FAK binds SRC and GRB2. C-CBL E3 ligase domain regulates receptor tyrosine kinase internalization through ubiquitination and its ring finger domain stabilizes the FAK-SRC-actin cytoskeleton thereby promoting cellular motility. C-CBL knockdown was associated with decreased protein and/or mRNA levels of SRC, FAK and GRB2. Taken together, we have provided evidence that c-CBL plays a role in melanoma cell proliferation, migration and invasion as well as inhibition of the FAK-GRB2-SRC nexus. Our findings indicate that additional studies are warranted to further dissect the role of c-CBL in melanoma and determine the therapeutic potential of its inhibition.
Background/Objectives: A variety of dietary fibers have been shown to alter satiety hormone gene expression and secretion. The objective of this study was to examine plasma satiety hormone ...concentrations in healthy subjects consuming either PolyGlycopleX (PGX) or control (skim milk powder) for 21 days. Subjects/Methods: A randomized, double-blind, placebo-controlled clinical study was conducted in 54 healthy male and female adults. Participants consumed 5 g per day of PGX or control for 1 week followed by 2 additional weeks of 10 g per day of assigned product (n=27 per group). Primary outcomes measured at three visits (V1, V2 and V3) were plasma active glucagon-like peptide-1 (GLP-1) total ghrelin, peptide YY (PYY) and insulin. Results: There was a significant effect of visit for fasting PYY with control participants experiencing decreased PYY levels over time while PGX prevented this decline. When stratified by body mass index (BMI), PGX increased fasting PYY levels from week 1 to week 3 compared with control in participants with BMI <23 kg/m2. There was a significant effect of visit for fasting ghrelin with levels decreasing in both PGX and control groups over time. No differences were detected in fasting GLP-1 levels. Although there was a 14% reduction in fasting insulin between V1 and V3 with PGX this was not significantly different from control. Conclusions: PGX is a highly viscous, functional fiber that modifies satiety hormone secretion in healthy adults. Its’ potential to act similarly in overweight adults warrants investigation.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, VSZLJ, ZAGLJ
This technical note presents an overview of the Chemistry-Climate Model Validation Diagnostic (CCMVal-Diag) tool for model evaluation. The CCMVal-Diag tool is a flexible and extensible open source ...package that facilitates the complex evaluation of global models. Models can be compared to other models, ensemble members (simulations with the same model), and/or many types of observations. The initial construction and application is to coupled chemistry-climate models (CCMs) participating in CCMVal, but the evaluation of climate models that submitted output to the Coupled Model Intercomparison Project (CMIP) is also possible. The package has been used to assist with analysis of simulations for the 2010 WMO/UNEP Scientific Ozone Assessment and the SPARC Report on the Evaluation of CCMs. The CCMVal-Diag tool is described and examples of how it functions are presented, along with links to detailed descriptions, instructions and source code. The CCMVal-Diag tool supports model development as well as quantifies model changes, both for different versions of individual models and for different generations of community-wide collections of models used in international assessments. The code allows further extensions by different users for different applications and types, e.g. to other components of the Earth system. User modifications are encouraged and easy to perform with minimum coding.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Periplasmic sensor domains from two methyl-accepting chemotaxis proteins from
Geobacter sulfurreducens (encoded by genes GSU0935 and GSU0582) were expressed in
Escherichia coli. The sensor domains ...were isolated, purified, characterized in solution, and their crystal structures were determined. In the crystal, both sensor domains form swapped dimers and show a PAS-type fold. The swapped segment consists of two helices of about 45 residues at the N terminus with the hemes located between the two monomers. In the case of the GSU0582 sensor, the dimer contains a crystallographic 2-fold symmetry and the heme is coordinated by an axial His and a water molecule. In the case of the GSU0935 sensor, the crystals contain a non-crystallographic dimer, and surprisingly, the coordination of the heme in each monomer is different; monomer A heme has His-Met ligation and monomer B heme has His-water ligation as found in the GSU0582 sensor. The structures of these sensor domains are the first structures of PAS domains containing covalently bound heme. Optical absorption, electron paramagnetic resonance and NMR spectroscopy have revealed that the heme groups of both sensor domains are high-spin and low-spin in the oxidized and reduced forms, respectively, and that the spin-state interconversion involves a heme axial ligand replacement. Both sensor domains bind NO in their ferric and ferrous forms but bind CO only in the reduced form. The binding of both NO and CO occurs
via an axial ligand exchange process, and is fully reversible. The reduction potentials of the sensor domains differ by 95 mV (−
156 mV and −
251 mV for sensors GSU0582 and GSU0935, respectively). The swapped dimerization of these sensor domains and redox-linked ligand switch might be related to the mechanism of signal transduction by these chemotaxis proteins.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The objective of this study was to determine whether nitric oxide (NO) is responsible for the vascular smooth muscle relaxation elicited by endothelium-derived relaxing factor (EDRF). EDRF is an ...unstable humoral substance released from artery and vein that mediates the action of endothelium-dependent vasodilators. NO is an unstable endothelium-independent vasodilator that is released from vasodilator drugs such as nitroprusside and glyceryl trinitrate. We have repeatedly observed that the actions of NO on vascular smooth muscle closely resemble those of EDRF. In the present study the vascular effects of EDRF released from perfused bovine intrapulmonary artery and vein were compared with the effects of NO delivered by superfusion over endotheliumdenuded arterial and venous strips arranged in a cascade. EDRF was indistinguishable from NO in that both were labile (t1/2 = 3-5 sec),, inactivated by pyrogallol or superoxide anion, stabilized by superoxide dismutase, and inhibited by oxyhemoglobin or potassium. Both EDRF and NO produced comparable increases in cyclic GMP accumulation in artery and vein, and this cyclic GMP accumulation was inhibited by pyrogallol, oxyhemoglobin, potassium, and methylene blue. EDRF was identified chemically as NO, or a labile nitroso species, by two procedures. First, like NO, EDRF released from freshly isolated aortic endothelial cells reacted with hemoglobin to yield nitrosylhemoglobin. Second, EDRF and NO each similarly promoted the diazotization of sulfanilic acid and yielded the same reaction product after coupling with N-(1-naphthyl)-ethylenediamine. Thus, EDRF released from artery and vein possesses identical biological and chemical properties as NO.
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