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31.
Debanu Das  Robert D. Finn  Polat Abdubek  Tamara Astakhova  Herbert L. Axelrod  Constantina Bakolitsa  Xiaohui Cai  Dennis Carlton  Connie Chen  Hsiu‐Ju Chiu  Michelle Chiu  Thomas Clayton  Marc C. Deller  Lian Duan  Kyle Ellrott  Carol L. Farr  Julie Feuerhelm  Joanna C. Grant  Anna Grzechnik  Gye Won Han  Lukasz Jaroszewski  Kevin K. Jin  Heath E. Klock  Mark W. Knuth  Piotr Kozbial  S. Sri Krishna  Abhinav Kumar  Winnie W. Lam  David Marciano  Mitchell D. Miller  Andrew T. Morse  Edward Nigoghossian  Amanda Nopakun  Linda Okach  Christina Puckett  Ron Reyes  Henry J. Tien  Christine B. Trame  Henry van den Bedem  Dana Weekes  Tiffany Wooten  Qingping Xu  Andrew Yeh  Jiadong Zhou  Keith O. Hodgson  John Wooley  Marc‐André Elsliger  Ashley M. Deacon  Adam Godzik  Scott A. Lesley  Ian A. Wilson 《Protein science : a publication of the Protein Society》2010,19(11):2131-2140
Sufu (Suppressor of Fused), a two‐domain protein, plays a critical role in regulating Hedgehog signaling and is conserved from flies to humans. A few bacterial Sufu‐like proteins have previously been identified based on sequence similarity to the N‐terminal domain of eukaryotic Sufu proteins, but none have been structurally or biochemically characterized and their function in bacteria is unknown. We have determined the crystal structure of a more distantly related Sufu‐like homolog, NGO1391 from Neisseria gonorrhoeae, at 1.4 Å resolution, which provides the first biophysical characterization of a bacterial Sufu‐like protein. The structure revealed a striking similarity to the N‐terminal domain of human Sufu (r.m.s.d. of 2.6 Å over 93% of the NGO1391 protein), despite an extremely low sequence identity of ~15%. Subsequent sequence analysis revealed that NGO1391 defines a new subset of smaller, Sufu‐like proteins that are present in ~200 bacterial species and has resulted in expansion of the SUFU (PF05076) family in Pfam.  相似文献   
32.
West Nile Virus (WNV) is the causative agent of a vector-borne, zoonotic disease with a worldwide distribution. Recent expansion and introduction of WNV into new areas, including southern Europe, has been associated with severe disease in humans and equids, and has increased concerns regarding the need to prevent and control future WNV outbreaks. Since 2010, 524 confirmed human cases of the disease have been reported in Greece with greater than 10% mortality. Infected mosquitoes, wild birds, equids, and chickens have been detected and associated with human disease. The aim of our study was to establish a monitoring system with wild birds and reported human cases data using Geographical Information System (GIS). Potential distribution of WNV was modelled by combining wild bird serological surveillance data with environmental factors (e.g. elevation, slope, land use, vegetation density, temperature, precipitation indices, and population density). Local factors including areas of low altitude and proximity to water were important predictors of appearance of both human and wild bird cases (Odds Ratio = 1,001 95%CI = 0,723–1,386). Using GIS analysis, the identified risk factors were applied across Greece identifying the northern part of Greece (Macedonia, Thrace) western Greece and a number of Greek islands as being at highest risk of future outbreaks. The results of the analysis were evaluated and confirmed using the 161 reported human cases of the 2012 outbreak predicting correctly (Odds = 130/31 = 4,194 95%CI = 2,841–6,189) and more areas were identified for potential dispersion in the following years. Our approach verified that WNV risk can be modelled in a fast cost-effective way indicating high risk areas where prevention measures should be implemented in order to reduce the disease incidence.  相似文献   
33.
The aim of this work was to explore the associations between family factors, including divorce, and children's overweight as well as eating and physical activity patterns in a population-based sample of healthy school-aged children. In this cross-sectional study, 1,138 children (53% girls; age: 11.2 +/- 0.7 years) from elementary schools in the Attica region participated. Their parents provided sociodemographic information, including their marital status. Overweight status classification was based on weight and height measurements and BMI evaluation. Children completed a physical activity checklist and a questionnaire on meal patterns and eating behaviors. The Eating Style score was calculated: the higher the score, the more frequent a child was engaged in less-structured feeding practices promoting food intake for reasons other than hunger. Analysis revealed significant association between family divorce and children's overweight: compared with children of married parents, those of divorced had significantly higher BMI levels (20.0 +/- 3.6 kg/m(2) vs. 21.3 +/- 3.4 kg/m(2), respectively, P = 0.007). Controlling for socioeconomic and physical activity factors, divorce remains a significant predictor of a higher BMI, along with older age, higher father's and mother's BMI, less children in the family, and more minutes of daily screen time. Children who had experienced a divorce in their family also reported higher Eating Style score, even after adjusting for potential confounders. In conclusion, in this sample of fifth and sixth graders, unfavorable family circumstances have been associated with children's overweight, as well as with aspects of their eating behavior, namely eating style in relation to conditions around food consumption and hunger, independent of other socioeconomic factors.  相似文献   
34.
The synthesis and pharmacological evaluation of a series of amide derivatives of NSAIDs with L-cysteine ethyl ester is described. The novel derivatives are potent antiinflammatory, antioxidant and hypocholesterolemic-hypolipidemic agents, while they demonstrate considerably reduced gastrointestinal toxicity. This molecular modification may offer a general route to safer antiinflammatory agents, potentially suitable for chronic use in conditions such as neurodegenerative disorders.  相似文献   
35.
A fast screening method of whole blood was proposed for enantiorecognition of free L‐T3 , L‐T4, and D‐T4. Stochastic microsensors based on four inulins (IN, IQ, TEX, and HD) immobilized on diamond paste (DP) were used for recognition of free L‐T3 , L‐T4, and D‐T4. For the enantiorecognition of free L‐T4 and D‐T4 in whole blood and pharmaceutical samples, the best microsensor was the one based on TEX/DP (wide linear concentration ranges, and low limits of quantification). The best limit of detection for the assay of free L‐T3 (400 fmol/L) was recorded using the microsensors based on HD/DP, while for the assay of free L‐T4, and D‐T4 the best limit of determination (1 pmol/L) was recorded using the TX/DP‐based microsensor. For the enantiorecognition of free L‐T3 in whole blood and pharmaceutical samples the best microsensor was the one based on HD/DP (the wider linear concentration range, and the lower limit of quantification – of pmol/L magnitude order). For the enantiorecognition of free L‐T3 in whole blood and pharmaceutical samples the best microsensor was the one based on HD/DP (the wider linear concentration range, and the lower limit of quantification – of pmol/L magnitude order). Free L‐T3 , L‐T4, and D‐T4 were recovered with high reliabilities in whole blood samples (recoveries higher than 99.00%, with RSD values lower than 1.00%) and pharmaceutical samples (recoveries higher than 95.00% with RSD values lower than 1.00%). Chirality 27:973–978, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
36.
The vinculin binding site on alpha-actinin was determined by cryo-electron microscopy of 2D arrays formed on phospholipid monolayers doped with a nickel chelating lipid. Chicken smooth muscle alpha-actinin was cocrystallized with the beta1-integrin cytoplasmic domain and a vinculin fragment containing residues 1-258 (vinculin(D1)). Vinculin(D1) was located at a single site on alpha-actinin with 60-70% occupancy. In these arrays, alpha-actinin lacks molecular 2-fold symmetry and the two ends of the molecule, which contain the calmodulin-like and actin binding domains, are held in distinctly different environments. The vinculin(D1) difference density has a shape very suggestive of the atomic structure. The atomic model of the complex juxtaposes the alpha-actinin binding site on vinculin(D1) with the N-terminal lobe of the calmodulin-like domain on alpha-actinin. The results show that the interaction between two species with weak affinity can be visualized in a membrane-like environment.  相似文献   
37.
IGF-1 is one of the key molecules in cancer biology; however, little is known about the role of the preferential expression of the premature IGF-1 isoforms in prostate cancer. We have examined the role of the cleaved COO– terminal peptide (PEc) of the third IGF-1 isoform, IGF-1Ec, in prostate cancer. Our evidence suggests that endogenously produced PEc induces cellular proliferation in the human prostate cancer cells (PC-3) in vitro and in vivo, by activating the ERK1/2 pathway in an autocrine/paracrine manner. PEc overexpressing cells and tumors presented evidence of epithelial to mesenchymal transition, whereas the orthotopic injection of PEc-overexpressing, normal prostate epithelium cells (HPrEC) in SCID mice was associated with increased metastatic rate. In humans, the IGF-1Ec expression was detected in prostate cancer biopsies, where its expression correlates with tumor stage. Our data describes the action of PEc in prostate cancer biology and defines its potential role in tumor growth, progression and metastasis.  相似文献   
38.
The reactions of methyl 2-pyridyl ketone oxime, (py)C(Me)NOH, with MSO4 · xH2O (M = Zn, x = 7; M = Cd, x = 8/3), in the absence of an external base, have been investigated. The synthetic study has led to the two new complexes [Zn(SO4){(py)C(Me)NOH}(H2O)3] · H2O (1 · H2O) and [Zn2(SO4)2{(py)C(Me)NOH}4] · (py)C(Me)NOH [2 · (py)C(Me)NOH], and the coordination polymer [Cd(SO4){(py)C(Me)NOH}(H2O)]n · [Cd(SO4){(py)C(Me)NOH}(H2O)2]n (3). In the three complexes the organic ligand chelates through its nitrogen atoms. The sulfate anion in 1 · H2O is monodentate; the complex molecule is the mer isomer considering the positions of the aqua ligands. The ZnII centers in 2 · (py)C(Me)NOH are bridged by two syn, anti η112 ligands; each metal ion has the cis-cis-trans disposition of the coordinated sulfate oxygen, pyridyl nitrogen and oxime nitrogens, respectively. The molecular structure of 3 is unique consisting of two different linear and ladder - type chains. π-π stacking interactions and/or hydrogen bonds lead to the formation of interesting supramolecular architectures in the three complexes. The thermal decomposition of complex 3 has been studied. Characteristic vibrational (IR, Raman) bands are discussed in terms of the nature of bonding and the structures of the three complexes.  相似文献   
39.
Human tissue kallikrein-related peptidases (KLKs) are 15 hormonally regulated genes on chromosome 19q13.4 encoding secreted serine proteases. Many KLKs are expressed throughout the female reproductive system and found in cervico-vaginal fluid (CVF). Immunohistochemistry was performed to determine KLK localization in the female reproductive system (fallopian tube, endometrium, cervix and vagina tissues). KLK levels were measured in CVF and saliva over the menstrual cycle to study whether KLKs are regulated by hormonal changes during the cycle. In vitro cleavage analysis was performed to establish whether KLKs may play a role in vaginal epithelial desquamation, mucus remodeling or processing of antimicrobial proteins. KLKs were localized in the glandular epithelium of the fallopian tubes and endometrium, the cervical mucus-secreting epithelium and vaginal stratified squamous epithelium. KLK levels peaked in CVF and saliva after ovulation. In vitro cleavage analysis confirmed KLKs 5 and 12 as capable of digesting desmoglein and desmocollin adhesion proteins and cervical mucin proteins 4 and 5B. KLK5 can digest defensin-1alpha, suggesting it may aid in cervico-vaginal host defense. We provide evidence of potential physiological roles for KLKs in cervico-vaginal physiology: in desquamation of vaginal epithelial cells, remodeling of cervical mucus and processing of antimicrobial proteins.  相似文献   
40.
The genome projects have unearthed an enormous diversity of genes of unknown function that are still awaiting biological and biochemical characterization. These genes, as most others, can be grouped into families based on sequence similarity. The PFAM database currently contains over 2,200 such families, referred to as domains of unknown function (DUF). In a coordinated effort, the four large-scale centers of the NIH Protein Structure Initiative have determined the first three-dimensional structures for more than 250 of these DUF families. Analysis of the first 248 reveals that about two thirds of the DUF families likely represent very divergent branches of already known and well-characterized families, which allows hypotheses to be formulated about their biological function. The remainder can be formally categorized as new folds, although about one third of these show significant substructure similarity to previously characterized folds. These results infer that, despite the enormous increase in the number and the diversity of new genes being uncovered, the fold space of the proteins they encode is gradually becoming saturated. The previously unexplored sectors of the protein universe appear to be primarily shaped by extreme diversification of known protein families, which then enables organisms to evolve new functions and adapt to particular niches and habitats. Notwithstanding, these DUF families still constitute the richest source for discovery of the remaining protein folds and topologies.  相似文献   
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