bluuebunny/crossref_metadata_2025_split huggingface dataset:
Expression of mucoid induction factor MucE is dependent upon the alternate sigma factor AlgU in Pseudomonas aeruginosa
Authors: Yin Yeshi , Damron F Heath , Withers T Ryan , Pritchett Christopher L , Wang Xin , Schurr Michael J , Yu Hongwei D 
Published: October 2013

Abstract

Background
Alginate overproduction in P. aeruginosa, also referred to as mucoidy, is a poor prognostic marker for patients with cystic fibrosis (CF). We previously reported the construction of a unique mucoid strain which overexpresses a small envelope protein MucE leading to activation of the protease AlgW. AlgW then degrades the anti-sigma factor MucA thus releasing the alternative sigma factor AlgU/T (σ22) to initiate transcription of the alginate biosynthetic operon.

Results
In the current study, we mapped the mucE transcriptional start site, and determined that P
mucE
activity was dependent on AlgU. Additionally, the presence of triclosan and sodium dodecyl sulfate was shown to cause an increase in P
mucE
activity. It was observed that mucE-mediated mucoidy in CF isolates was dependent on both the size of MucA and the genotype of algU. We also performed shotgun proteomic analysis with cell lysates from the strains PAO1, VE2 (PAO1 with constitutive expression of mucE) and VE2ΔalgU (VE2 with in-frame deletion of algU). As a result, we identified nine algU-dependent and two algU-independent proteins that were affected by overexpression of MucE.

Conclusions
Our data indicates there is a positive feedback regulation between MucE and AlgU. Furthermore, it seems likely that MucE may be part of the signal transduction system that senses certain types of cell wall stress to P. aeruginosa.
Combined linkage and association mapping reveals candidates for Scmv1, a major locus involved in resistance to sugarcane mosaic virus (SCMV) in maize
Authors: Tao Yongfu , Jiang Lu , Liu Qingqing , Zhang Yan , Zhang Rui , Ingvardsen Christina Roenn , Frei Ursula Karoline , Wang Baobao , Lai Jinsheng , Lübberstedt Thomas , Xu Mingliang 
Published: October 2013

Abstract

Background
Sugarcane mosaic virus (SCMV) disease causes substantial losses of grain yield and forage biomass in susceptible maize cultivars. Maize resistance to SCMV is associated with two dominant genes, Scmv1 and Scmv2, which are located on the short arm of chromosome 6 and near the centromere region of chromosome 3, respectively. We combined both linkage and association mapping to identify positional candidate genes for Scmv1.

Results

Scmv1 was fine-mapped in a segregating population derived from near-isogenic lines and further validated and fine-mapped using two recombinant inbred line populations. The combined results assigned the Scmv1 locus to a 59.21-kb interval, and candidate genes within this region were predicted based on the publicly available B73 sequence. None of three predicted genes that are possibly involved in the disease resistance response are similar to receptor-like resistance genes. Candidate gene–based association mapping was conducted using a panel of 94 inbred lines with variable resistance to SCMV. A presence/absence variation (PAV) in the Scmv1 region and two polymorphic sites around the Zmtrx-h gene were significantly associated with SCMV resistance.

Conclusion
Combined linkage and association mapping pinpoints Zmtrx-h as the most likely positional candidate gene for Scmv1. These results pave the way towards cloning of Scmv1 and facilitate marker-assisted selection for potyvirus resistance in maize.
Mechanical stress in Arabidopsis leaves orients microtubules in a 'continuous’ supracellular pattern
Authors: Jacques Eveline , Verbelen Jean-Pierre , Vissenberg Kris 
Published: October 2013

Abstract

Background
Cortical microtubules form a dynamic network and continuously undergo shrinking (catastrophe), pausing and rebuilding (rescue). The advantage of such a dynamic system is that it may mediate appropriate responses in a short time span. Microtubules are known to play a pivotal role in determining the orientation of the cellulose microfibril deposition in the plant cell wall. The latter is a solid exoskeleton surrounding the protoplast. It forms the physical framework that interconnects most cells and has to bear the tensile stresses within the tissue. Here we describe the effect of externally applied pressure on microtubule organization in growing Arabidopsis leaves.

Results
Confocal microscopy examination of transgenic plants bearing GFP-tagged TUA6 proteins led to the observation that application of an additional mechanical pressure on growing Arabidopsis leaves triggers an excessive bundling of microtubules within the individual cell. Besides, the microtubules seem to align in neighboring cells, creating a 'continuous’ supracellular pattern. This effect occurs within 3 hours after applied external force and is age-dependent, whereby only cells of leaves up to 19 days after sowing (DAS) are susceptible to the applied pressure.

Conclusions
Upon externally applied pressure on developing Arabidopsis leaves, microtubules bundle and rearrange to form seemingly continuous supracellular patterns. As microtubules guide the cellulose synthase complexes, this observed reorganisation pattern probably affects the cellulose deposition, contributing to the reinforcement of the cell wall in a particular position to cope with the extra-applied pressure. The age-effect is reasonable, since younger cells, which are actively shaping their cell walls, are more vulnerable to altered mechanical stresses while in leaves older than 19 DAS, the walls are more robust and therefore can sustain the applied forces.
Child-oriented marketing techniques in snack food packages in Guatemala
Authors: Chacon Violeta , Letona Paola , Barnoya Joaquin 
Published: October 2013

Abstract

Background
Childhood overweight in Guatemala is now becoming a public health concern. Child-oriented marketing contributes to increase children’s food preference, purchase and consumption. This study sought to assess the availability of child-oriented snack foods sold in school kiosks and convenience stores near public schools in Guatemala, to identify the marketing techniques used in child-oriented snack food packages and to classify the snacks as “healthy” or “less-healthy”.

Methods
We purchased all child-oriented snacks found in stores inside and within 200 square meters from four schools in an urban community. Snacks were classified as child-oriented if the package had any promotional characters, premium offers, children′s television/movie tie-ins, sports references, or the word “child”. We used a checklist to assess child-oriented references and price. Snacks were classified as “healthy” or “less-healthy” according to the UK standards for the Nutritional Profiling Model.

Results
We analyzed 106 packages found in 55 stores. The most commonly used technique was promotional characters (92.5%) of which 32.7% were brand-specific characters. Premium offers were found in 34% of packages and were mostly collectibles (50%). Most marketing techniques were located on the front and covered nearly 25% of the package surface. Median (interquartile range) price was US$ 0.19 (0.25). Nutrition labels were found in 91 (86%) packages and 41% had a nutrition related health claim. Most snacks (97.1%) were classified as “less-healthy”.

Conclusion
In Guatemala, the food industry targets children through several marketing techniques promoting inexpensive and unhealthy snacks in the school environment. Evidence-based policies restricting the use of promotional characters in unhealthy snack food packages need to be explored as a contributing strategy to control the obesity epidemic.
Structural and functional characterisation of the methionine adenosyltransferase from Thermococcus kodakarensis
Authors: Schlesier Julia , Siegrist Jutta , Gerhardt Stefan , Erb Annette , Blaesi Simone , Richter Michael , Einsle Oliver , Andexer Jennifer N 
Published: October 2013

Abstract

Background
Methionine adenosyltransferases catalyse the synthesis of S-adenosylmethionine, a cofactor abundant in all domains of life. In contrast to the enzymes from bacteria and eukarya that show high sequence similarity, methionine adenosyltransferases from archaea diverge on the amino acid sequence level and only few conserved residues are retained.

Results
We describe the initial characterisation and the crystal structure of the methionine adenosyltransferase from the hyperthermophilic archaeon Thermococcus kodakarensis. As described for other archaeal methionine adenosyltransferases the enzyme is a dimer in solution and shows high temperature stability. The overall structure is very similar to that of the bacterial and eukaryotic enzymes described, with some additional features that might add to the stability of the enzyme. Compared to bacterial and eukaryotic structures, the active site architecture is largely conserved, with some variation in the substrate/product-binding residues. A flexible loop that was not fully ordered in previous structures without ligands in the active side is clearly visible and forms a helix that leaves an entrance to the active site open.

Conclusions
The similar three-dimensional structures of archaeal and bacterial or eukaryotic methionine adenosyltransferases support that these enzymes share an early common ancestor from which they evolved independently, explaining the low similarity in their amino acid sequences. Furthermore, methionine adenosyltransferase from T. kodakarensis is the first structure without any ligands bound in the active site where the flexible loop covering the entrance to the active site is fully ordered, supporting a mechanism postulated earlier for the methionine adenosyltransferase from E. coli. The structure will serve as a starting point for further mechanistic studies and permit the generation of enzyme variants with different characteristics by rational design.
Structural and biochemical characterization of the essential DsbA-like disulfide bond forming protein from Mycobacterium tuberculosis
Authors: Chim Nicholas , Harmston Christine A , Guzman David J , Goulding Celia W 
Published: October 2013

Abstract

Background
Bacterial D is ulfide b ond forming (Dsb) proteins facilitate proper folding and disulfide bond formation of periplasmic and secreted proteins. Previously, we have shown that Mycobacterium tuberculosis Mt-DsbE and Mt-DsbF aid in vitro oxidative folding of proteins. The M. tuberculosis proteome contains another predicted membrane-tethered Dsb protein, Mt-DsbA, which is encoded by an essential gene.

Results
Herein, we present structural and biochemical analyses of Mt-DsbA. The X-ray crystal structure of Mt-DsbA reveals a two-domain structure, comprising a canonical thioredoxin domain with the conserved CXXC active site cysteines in their reduced form, and an inserted α-helical domain containing a structural disulfide bond. The overall fold of Mt-DsbA resembles that of other DsbA-like proteins and not Mt-DsbE or Mt-DsbF. Biochemical characterization demonstrates that, unlike Mt-DsbE and Mt-DsbF, Mt-DsbA is unable to oxidatively fold reduced, denatured hirudin. Moreover, on the substrates tested in this study, Mt-DsbA has disulfide bond isomerase activity contrary to Mt-DsbE and Mt-DsbF.

Conclusion
These results suggest that Mt-DsbA acts upon a distinct subset of substrates as compared to Mt-DsbE and Mt-DsbF. One could speculate that Mt-DsbE and Mt-DsbF are functionally redundant whereas Mt-DsbA is not, offering an explanation for the essentiality of Mt-DsbA in M. tuberculosis.
¹H NMR-based metabolic profiling of human rectal cancer tissue
Authors: Wang Huijuan , Wang Liang , Zhang Hailong , Deng Pengchi , Chen Jie , Zhou Bin , Hu Jing , Zou Jun , Lu Wenjie , Xiang Pu , Wu Tianming , Shao Xiaoni , Li Yuan , Zhou Zongguang , Zhao Ying-Lan 
Published: October 2013

Abstract

Background
Rectal cancer is one of the most prevalent tumor types. Understanding the metabolic profile of rectal cancer is important for developing therapeutic approaches and molecular diagnosis.

Methods
Here, we report a metabonomics profiling of tissue samples on a large cohort of human rectal cancer subjects (n = 127) and normal controls (n = 43) using 1H nuclear magnetic resonance (1H NMR) based metabonomics assay, which is a highly sensitive and non-destructive method for the biomarker identification in biological systems. Principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) and orthogonal projection to latent structure with discriminant analysis (OPLS-DA) were applied to analyze the 1H-NMR profiling data to identify the distinguishing metabolites of rectal cancer.

Results
Excellent separation was obtained and distinguishing metabolites were observed among the different stages of rectal cancer tissues (stage I = 35; stage II = 37; stage III = 37 and stage IV = 18) and normal controls. A total of 38 differential metabolites were identified, 16 of which were closely correlated with the stage of rectal cancer. The up-regulation of 10 metabolites, including lactate, threonine, acetate, glutathione, uracil, succinate, serine, formate, lysine and tyrosine, were detected in the cancer tissues. On the other hand, 6 metabolites, including myo-inositol, taurine, phosphocreatine, creatine, betaine and dimethylglycine were decreased in cancer tissues. These modified metabolites revealed disturbance of energy, amino acids, ketone body and choline metabolism, which may be correlated with the progression of human rectal cancer.

Conclusion
Our findings firstly identify the distinguishing metabolites in different stages of rectal cancer tissues, indicating possibility of the attribution of metabolites disturbance to the progression of rectal cancer. The altered metabolites may be as potential biomarkers, which would provide a promising molecular diagnostic approach for clinical diagnosis of human rectal cancer. The role and underlying mechanism of metabolites in rectal cancer progression are worth being further investigated.
Family history of hepatocellulcar carcinoma is not associated with its patients’ prognosis after hepatectomy
Authors: Huang Jia , Zhang Yaojun , Chen Meixian , Huang Junting , Xu Li , Chen Minshan 
Published: October 2013

Abstract

Background
Family history of liver cancer is a major risk factor for hepatocellular carcinoma (HCC). In this study, we investigated the prognosis of patients with HCC with or without family history.

Methods
Data for 1,313 patients who underwent hepatectomy as initial treatment for HCC between 2000 and 2008 at a tertiary cancer center hospital were retrieved from a prospective database. A positive family history was defined as a self-reported history of HCC in first-degree relatives. Clinicopathologic characteristics were compared by family history. Kaplan-Meier method and Cox proportional hazards regressions were applied for overall survival (OS) and disease-free survival (DFS).

Results
Of 1,313 patients, 169 patients (12.9%) had first-degree relatives with a history of HCC. There were no significant differences between patients with or without family history in basic clinicopathologic characteristics. In either whole group or each stage according to the TNM staging system, first-degree family history was not associated with survival in all patients, hepatitis B virus-positive patients, as well as male patients. Multivariate analysis revealed that first-degree family history was not a prognostic factor, either for OS or DFS.

Conclusion
A first-degree family history of HCC is not associated with its patients’ prognosis after hepatectomy.
CER1gene variations associated with bone mineral density, bone markers, and early menopause in postmenopausal women
Authors: Koromila Theodora , Georgoulias Panagiotis , Dailiana Zoe , Ntzani Evangelia E , Samara Stavroula , Chassanidis Chris , Aleporou-Marinou Vassiliki , Kollia Panagoula 
Published: October 2013

Abstract

Background
Osteoporosis has a multifactorial pathogenesis characterized by a combination of low bone mass and increased fragility. In our study, we focused on the effects of polymorphisms in CER1 and DKK1 genes, recently reported as important susceptibility genes for osteoporosis, on bone mineral density (BMD) and bone markers in osteoporotic women. Our objective was to evaluate the effect of CER1 and DKK1 variations in 607 postmenopausal women. The entire DKK1 gene sequence and five selected CER1 SNPs were amplified and resequenced to assess whether there is a correlation between these genes and BMD, early menopause, and bone turnover markers in osteoporotic patients.

Results
Osteoporotic women seem to suffer menopause 2 years earlier than the control group. The entire DKK1 gene sequence analysis revealed six variations. There was no correlation between the six DKK1 variations and osteoporosis, in contrast to the five common CER1 variations that were significantly associated with BMD. Additionally, osteoporotic patients with rs3747532 and rs7022304 CER1 variations had significantly higher serum levels of parathyroid hormone and calcitonin and lower serum levels of osteocalcin and IGF-1.

Conclusions
No significant association between the studied DKK1 variations and osteoporosis was found, while CER1 variations seem to play a significant role in the determination of osteoporosis and a potential predictive role, combined with bone markers, in postmenopausal osteoporotic women.
A simple strategy to decrease fatal carotid blowout syndrome after stereotactic body reirradiaton for recurrent head and neck cancers
Authors: Yazici Gozde , Sanlı Tolga Yusuf , Cengiz Mustafa , Yuce Deniz , Gultekin Melis , Hurmuz Pervin , Yıldız Ferah , Zorlu Faruk , Akyol Fadil , Gurkaynak Murat , Ozyigit Gokhan 
Published: October 2013

Abstract

Background
This study aimed to compare the therapeutic outcomes and fatal carotid blow out syndrome (CBOS) incidence rates between two different stereotactic body radiotherapy (SBRT) protocols.

Methods
The study included 75 patients with inoperable locally recurrent head and neck cancer treated with SBRT in our department between June 2007 and March 2011. The first 43 patients were treated sequentially (group I). Then our SBRT protocol was changed due to the high rate of CBOS, and the following 32 patients were treated every other day in a prospective institutional protocol (group II).

Results
Median overall survival in group I and group II was 11 months and 23 months, respectively (P = 0.006). We observed 11 cases of CBOS. Only 1 of 7 patients (14%) with CBOS survived in group I, whereas 2 of 4 patients (50%) in group II remain alive. CBOS free median overall survivals were 9 months, and 23 months in group I and group II respectively (P = 0.002). The median radiation dose received by the carotid artery in patients with CBOS was 36.5 Gy (range: 34–42.8 Gy), versus 34.7 Gy (range: 0–44 Gy) in the patients that didn’t have CBOS (P = 0.15). CBOS did not occur in any of the patients with a maximum carotid artery radiation dose <34 Gy.

Conclusions
Every other day SBRT protocol for re-irradiation of recurrent head and neck cancer is promising in terms of decreasing the incidence of fatal CBOS.
Giant mucocele originating from the middle concha in a 5-year-old child: a case report
Authors: Aslan Gaffar , Ugur Mehmet Birol , Başsüllü Nuray 
Published: October 2013

Abstract

Introduction
Mucoceles are mucus-filled, epithelial-lined sacs that slowly develop in the paranasal sinuses when sinus or concha bullosa drainage is obstructed by inflammatory processes, trauma, or prior surgery. They are extremely rare in children. Symptoms usually arise from the nasal obstruction or compression of neighboring structures.

Case presentation
This case report describes a 5-year-old Turkish boy with a 3-year history of nasal obstruction. A computed tomography scan showed a well-defined soft tissue density lesion, seemingly originating in the region of the middle concha and was suggestive of a middle concha mucocele. The mass was removed by endoscopic sinus surgery.

Conclusions
In the case of a child presenting with nasal obstruction, mucocele should be remembered in the differential diagnosis of intranasal tumors. Computed tomography and magnetic resonance imaging are helpful in making the diagnosis and endoscopic nasal surgery has proven successful in the treatment.
Secretion of polyhydroxybutyrate in Escherichia coli using a synthetic biological engineering approach
Authors: Rahman Asif , Linton Elisabeth , Hatch Alex D , Sims Ronald C , Miller Charles D 
Published: October 2013

Abstract

Background
Polyhydroxyalkanoates (PHAs) are a group of biodegradable plastics that are produced by a wide variety of microorganisms, mainly as a storage intermediate for energy and carbon. Polyhydroxybutyrate (PHB) is a short-chain-length PHA with interesting chemical and physical properties. Large scale production of PHB is not wide-spread mainly due to the downstream processing of bacterial cultures to extract the PHB. Secretion of PHB from Escherichia coli could reduce downstream processing costs. PHB are non-proteinaceous polymers, hence cannot be directly targeted for secretion. Phasin, PhaP1, is a low molecular weight protein that binds to PHB, reducing PHB granule size. In this study PHB is indirectly secreted with PhaP1 from E. coli via type I secretion using HlyA signal peptides.

Results
This study demonstrated the successful secretion of phasin and phasin bound PHB outside of the cell and into the culture medium. The secretion of PHB was initiated between 24 and 48 h after induction. After 48 h of culturing, 36% of the total PHB produced in the secreting strain was collected in the secreted fraction and 64% remained in the internal fraction. To further support the findings of this study, the PHB secretion phenomenon was observed using SEM.

Conclusions
From this study, the ability to use type I secretion to: 1) secrete phasin and 2) successfully secrete PHB has been shown.
Wilson’s disease in pregnancy: case series and review of literature
Authors: Malik Ayesha , Khawaja Ali , Sheikh Lumaan 
Published: October 2013

Abstract

Background
Wilson’s disease is a rare, autosomal recessive inherited disorder characterized by impaired liver metabolism of copper leading to decreased biliary excretion and incorporation of ceruloplasmin levels mainly in the liver and brain. Untreated Wilson’s disease has been shown to cause subfertility and even in cases where pregnancy occurs, it often results in spontaneous miscarriage.

Case presentations
We present four cases of successful pregnancy outcomes in three patients diagnosed with Wilson’s disease along with the literature review. All the patients were managed with zinc sulphate without any postnatal complications.

Conclusion
Patients with Wilson’s disease receiving regular treatment who remain asymptomatic are usually able to conceive and achieve successful outcomes. However, these pregnancies should be considered high risk and merit regular surveillance.