bluuebunny/crossref_metadata_2025 huggingface dataset:
Lethality of the covalent linkage between mislocalized major outer membrane lipoprotein and the peptidoglycan of Escherichia coli
Authors: Yakushi T , Tajima T , Matsuyama S , Tokuda H
Published: November 2016

The major outer membrane lipoprotein (Lpp) of Escherichia coli possesses serine at position 2, which is thought to function as the outer membrane sorting signal, and lysine at the C terminus, through which Lpp covalently associates with peptidoglycan. Arginine (R) is present before the C-terminal lysine in the wild-type Lpp (LppSK). By replacing serine (S) at position 2 with aspartate (D), the putative inner membrane sorting signal, and by deleting lysine (K) at the C terminus, Lpp mutants with a different residue at either position 2 (LppDK) or the C terminus (LppSR) or both (LppDR) were constructed. Expression of LppSR and LppDR little affected the growth of E. coli. In contrast, the number of viable cells immediately decreased when LppDK was expressed. Prolonged expression of LppDK inhibited separation of the inner and outer membranes by sucrose density gradient centrifugation, whereas short-term expression did not. Pulse-labeled LppDK and LppDR were localized in the inner membrane, indicating that the amino acid residue at position 2 functions as a sorting signal for the membrane localization of Lpp. LppDK accumulated in the inner membrane covalently associated with the peptidoglycan and thus prevented the separation of the two membranes. Globomycin, an inhibitor of lipoprotein-specific signal peptidase II, was lethal for E. coli only when Lpp possessed the C-terminal lysine. Taken together, these results indicate that the inner membrane accumulation of Lpp per se is not lethal for E. coli. Instead, a covalent linkage between the inner membrane Lpp having the C-terminal lysine and the peptidoglycan is lethal for E. coli, presumably due to the disruption of the cell surface integrity.
Lipopolysaccharide dependence of cyanophage sensitivity and aerobic nitrogen fixation in Anabaena sp. strain PCC 7120
Authors: Xu X , Khudyakov I , Wolk C P
Published: November 2016

Fox- mutants of Anabaena sp. strain PCC 7120 are unable to fix dinitrogen in the presence of oxygen. A fragment of the DNA of Anabaena sp. was cloned by complementation of a spontaneous Fox-, cyanophage-resistant mutant, R56, and characterized. Random insertion of transposon Tn5 delimited the complementing DNA to a 0.6-kb portion of the cloned fragment. Sequencing of this region and flanking DNA showed one complete open reading frame (ORF) similar to the gene rfbP (undecaprenyl-phosphate galactosephosphotransferase) and two partial ORFs similar to genes rfbD (GDP-D-mannose dehydratase) and rfbZ (first mannosyl transferase), all of which are active in the synthesis of the O antigen unit of the lipopolysaccharide (LPS) component of the outer membrane of gram-negative bacteria. In a transposon (Tn5-1087b)-induced, Fox-, cyanophage-resistant mutant, B14, the transposon was found within the same rfbP-like ORF. The three ORFs were insertionally inactivated with the omega cassette (P. Prentki and H. M. Krisch, Gene 29:303-313, 1984) or with Tn5::omega. Only the insertions in the rfbZ- and rfbP-like ORFs led to resistance to cyanophages A-1(L) and A-4(L) and to a Fox- phenotype. Electrophoretic analysis showed that interruption of the rfbZ- and rfbP-like ORFs resulted in a change in or loss of the characteristic pattern of the lengths of the LPS, whereas interruption of the rfbD-like ORF merely changed the distribution of the lengths of the LPS to one with a greater prevalence of low molecular weights. According to electron microscopy, interruption of the rfbP-like ORF may have led to aberrant deposition of the layers of the heterocyst envelope, resulting in increased leakage of oxygen into the heterocyst. The results suggest that modified LPS may prevent cyanophage infection of Anabaena sp. vegetative cells and the formation of a functional heterocyst envelope.
Identification and characterization of ssb and uup mutants with increased frequency of precise excision of transposon Tn10 derivatives: nucleotide sequence of uup in Escherichia coli
Authors: Reddy M , Gowrishankar J
Published: November 2016

A Lac+ papillation assay was used to identify mutants (tex) of Escherichia coli that exhibit an increased frequency of precise excision of a lacZ::Tn10dKan insertion. Three tex strains had suffered mutations in the gene (ssb) encoding the essential single-stranded DNA-binding protein SSB, which resulted in the following alterations in the 177-residue protein: G4D; L10F, P24S; and V102M. The phenotypes of these ssb mutants indicated that they were largely unaffected in other functions mediated by SSB, such as DNA replication, recombination, and repair. Strains with multicopy ssb+ exhibited a decreased frequency of Tn10dKan precise excision. Three other tex mutants had insertion mutations in the locus designated uup at 21.75 min on the linkage map. The nucleotide sequence of uup was determined, and the gene was inferred to encode a 625-amino-acid hydrophilic protein that belongs to the superfamily of ABC-domain proteins (with two pairs of the Walker A and B motifs), which are postulated to be involved in coupling ATP hydrolysis with other biological processes. The uup gene product shares extensive homology with the deduced sequences of two proteins of Haemophilus influenzae. The uup gene is also situated immediately upstream of (and is transcribed in the same direction as) the paraquat-inducible SoxRS-regulated pqi-5 gene, two reported promoters for which are situated within the uup coding sequence.
Three different putative phosphate transport receptors are encoded by the Mycobacterium tuberculosis genome and are present at the surface of Mycobacterium bovis BCG
Authors: Lefèvre P , Braibant M , de Wit L , Kalai M , Röeper D , Grötzinger J , Delville J P , Peirs P , Ooms J , Huygen K , Content J
Published: November 2016

A gene encoding a protein homologous to the periplasmic ABC phosphate binding receptor PstS from Escherichia coli was cloned and sequenced from a lambda gt11 library of Mycobacterium tuberculosis by screening with monoclonal antibody 2A1-2. Its degree of similarity to the E. coli PstS is comparable to those of the previously described M. tuberculosis phosphate binding protein pab (Ag78, Ag5, or 38-kDa protein) and another M. tuberculosis protein which we identified recently. We suggest that the three M. tuberculosis proteins share a similar function and could be named PstS-1, PstS-2, and PstS-3, respectively. Molecular modeling of their three-dimensional structures using the structure of the E. coli PstS as a template and their inducibility by phosphate starvation support this view. Recombinant PstS-2 and PstS-3 were produced and purified by affinity chromatography. With PstS-1, these proteins were used to demonstrate the specificity of three groups of monoclonal antibodies. Using these antibodies in flow cytometry and immunoblotting analyses, we demonstrate that the three genes are expressed and their protein products are present and accessible at the mycobacterial surface as well as in its culture filtrate. Together with the M. tuberculosis genes encoding homologs of the PstA, PstB, and PstC components we cloned before, the present data suggest that at least one, and possibly several, related and functional ABC phosphate transporters exist in mycobacteria. It is hypothesized that the mycobacterial gene duplications presented here may be a subtle adaptation of intracellular pathogens to phosphate starvation in their alternating growth environments.
Identification and characterization of the nifV-nifZ-nifT gene region from the filamentous cyanobacterium Anabaena sp. strain PCC 7120
Authors: Stricker O , Masepohl B , Klipp W , Böhme H
Published: November 2016

The nifV and leuA genes, which encode homocitrate synthase and alpha-isopropylmalate synthase, respectively, were cloned from the filamentous cyanobacterium Anabaena sp. strain PCC 7120 by a PCR-based strategy. Since the N-terminal parts of NifV and LeuA from other bacteria are highly similar to each other, a single pair of PCR primers was used to amplify internal fragments of both Anabaena strain 7120 genes. Sequence analysis of cloned PCR products confirmed the presence of two different nifV-like DNA fragments, which were subsequently used as nifV- and leuA-specific probes, respectively, to clone XbaI fragments of 2.1 kbp (pOST4) and 2.6 kbp (pOST2). Plasmid pOST4 carried the Anabaena strain 7120 nifV-nifZ-nifT genes, whereas pOST2 contained the leuA and dapF genes. The nifVZT genes were not located in close proximity to the main nif gene cluster in Anabaena strain 7120, and therefore nifVZT forms a second nif gene cluster in this strain. Overlaps between the nifV and nifZ genes and between the nifZ and nifT genes and the presence of a 1.8-kb transcript indicated that nifVZT might form one transcriptional unit. Transcripts of nifV were induced not only in a nitrogen-depleted culture but also by iron depletion irrespective of the nitrogen status. The nifV gene in Anabaena strain 7120 was interrupted by an interposon insertion (mutant strain BMB105) and by a plasmid integration via a single crossover with a nifV internal fragment as a site for recombination (mutant strain BMB106). Both mutant strains were capable of diazotrophic growth, and their growth rates were only slightly impaired compared to that of the wild type. Heterologous complementation of the Rhodobacter capsulatus nifV mutant R229I by the Anabaena strain 7120 nifV gene corroborated the assumption that Anabaena strain 7120 nifV also encodes a homocitrate synthase. In contrast, the Anabaena strain 7120 leuA gene did not complement the nifV mutation of R229I efficiently.
Molecular characterization of a genomic region in a Lactococcus bacteriophage that is involved in its sensitivity to the phage defense mechanism AbiA
Authors: Dinsmore P K , Klaenhammer T R
Published: November 2016

A spontaneous mutant of the lactococcal phage phi31 that is insensitive to the phage defense mechanism AbiA was characterized in an effort to identify the phage factor(s) involved in sensitivity of phi31 to AbiA. A point mutation was localized in the genome of the AbiA-insensitive phage (phi31A) by heteroduplex analysis of a 9-kb region. The mutation (G to T) was within a 738-bp open reading frame (ORF245) and resulted in an arginine-to-leucine change in the predicted amino acid sequence of the protein. The mutant phi31A-ORF245 reduced the sensitivity of phi31 to AbiA when present in trans, indicating that the mutation in ORF245 is responsible for the AbiA insensitivity of phi31A. Transcription of ORF245 occurs early in the phage infection cycles of phi31 and phi31A and is unaffected by AbiA. Expansion of the phi31 sequence revealed ORF169 (immediately upstream of ORF245) and ORF71 (which ends 84 bp upstream of ORF169). Two inverted repeats lie within the 84-bp region between ORF71 and ORF169. Sequence analysis of an independently isolated AbiA-insensitive phage, phi31B, identified a mutation (G to A) in one of the inverted repeats. A 118-bp fragment from phi31, encompassing the 84-bp region between ORF71 and ORF169, eliminates AbiA activity against phi31 when present in trans, establishing a relationship between AbiA and this fragment. The study of this region of phage phi31 has identified an open reading frame (ORF245) and a 118-bp DNA fragment that interact with AbiA and are likely to be involved in the sensitivity of this phage to AbiA.
Characterization of a glucose-repressed pyruvate kinase (Pyk2p) in Saccharomyces cerevisiae that is catalytically insensitive to fructose-1,6-bisphosphate
Authors: Boles E , Schulte F , Miosga T , Freidel K , Schlüter E , Zimmermann F K , Hollenberg C P , Heinisch J J
Published: November 2016

We have characterized the gene YOR347c of Saccharomyces cerevisiae and shown that it encodes a second functional pyruvate kinase isoenzyme, Pyk2p. Overexpression of the YOR347c/PYK2 gene on a multicopy vector restored growth on glucose of a yeast pyruvate kinase 1 (pyk1) mutant strain and could completely substitute for the PYK1-encoded enzymatic activity. PYK2 gene expression is subject to glucose repression. A pyk2 deletion mutant had no obvious growth phenotypes under various conditions, but the growth defects of a pyk1 pyk2 double-deletion strain were even more pronounced than those of a pyk1 single-mutation strain. Pyk2p is active without fructose-1,6-bisphosphate. However, overexpression of PYK2 during growth on ethanol did not cause any of the deleterious effects expected from a futile cycling between pyruvate and phosphoenolpyruvate. The results indicate that the PYK2-encoded pyruvate kinase may be used under conditions of very low glycolytic flux.
Cloning and characterization of cspL and cspP, two cold-inducible genes from Lactobacillus plantarum
Authors: Mayo B , Derzelle S , Fernández M , Léonard C , Ferain T , Hols P , Suárez J E , Delcour J
Published: November 2016

Two cold shock genes, cspL and cspP, have been cloned from two Lactobacillus plantarum strains. These genes, which are nonallelic, were present in all strains tested. The genes encode 66-amino-acid polypeptides related to each other and to the cold shock Csp family. Transcription of cspP rendered a single mRNA, while two cspL mRNAs were found with common 5' ends. The amounts of these transcripts increased moderately upon exposure of the cultures to cold.
Identification of greA encoding a transcriptional elongation factor as a member of the carA-orf-carB-greA operon in Pseudomonas aeruginosa PAO1
Authors: Lu C D , Kwon D H , Abdelal A T
Published: November 2016

A homolog of the transcriptional elongation factor, GreA, was identified in Pseudomonas aeruginosa PAO1. The deduced amino acid sequence for GreA from this organism exhibits 65.2% identity to its counterpart in Escherichia coli K-12. The nucleotide sequence of greA from P. aeruginosa overlaps by four bases the 3' terminus of carB which encodes the large subunit of carbamoylphosphate synthetase. S1 nuclease experiments showed that level of the greA transcript is elevated approximately 10-fold under conditions of pyrimidine limitation, consistent with the conclusion that transcription is initiated from the previously identified pyrimidine-sensitive promoter upstream of the carA-orf-carB-greA operon. Transcriptional fusion experiments showed the presence of an additional weak promoter within the carB sequence. A greA insertional mutant of Pseudomonas aerugionsa was constructed by gene replacement. The mutant derivative grew well in rich medium but did not grow in minimal medium supplemented by arginine and nucleosides. The greA phenotype was suppressed by secondary mutations at a relatively high rate, consistent with the notion of an important physiological role for GreA.
Nucleotide sequence of the Mycobacterium leprae katG region
Authors: Nakata N , Matsuoka M , Kashiwabara Y , Okada N , Sasakawa C
Published: November 2016

Synthetic oligonucleotide primers based on the DNA sequence data of the Escherichia coli, Mycobacterium tuberculosis, and Mycobacterium intracellulare katG genes encoding the heme-containing enzyme catalase-peroxidase were used to amplify and analyze the Mycobacterium leprae katG region by PCR. A 1.6-kb DNA fragment, which hybridized to an M. tuberculosis katG probe, was obtained from an M. leprae DNA template. Southern hybridization analysis with a probe derived from the PCR-amplified fragment showed that the M. leprae chromosome contains only one copy of the putative katG sequence in a 3.4-kb EcoRI-BamHI DNA segment. Although the nucleotide sequence of the katG region of M. leprae was approximately 70% identical to that of the M. tuberculosis katG gene, no open reading frame encoding a catalase-peroxidase was detectable in the whole sequence. Moreover, two DNA deletions of approximately 100 and 110 bp were found in the M. leprae katG region, and they seemed to be present in all seven M. leprae isolates tested. These results strongly suggest that M. leprae lacks a functional katG gene and catalase-peroxidase activity.
The integration host factor-DNA complex upstream of the early promoter of bacteriophage Mu is functionally symmetric
Authors: van Ulsen P , Hillebrand M , Zulianello L , van de Putte P , Goosen N
Published: November 2016

Inversion of the ihf site in the promoter region of the early promoter of bacteriophage Mu did not influence the integration host factor (IHF)-mediated functions. IHF bound to this inverted site could counteract H-NS-mediated repression, directly activate transcription, and support lytic growth of bacteriophage Mu. This implies that the IHF heterodimer and its asymmetrical binding site form a functionally symmetrical complex.
Missed opportunities for earlier diagnosis of HIV in patients who presented with advanced HIV disease: a retrospective cohort study
Authors: Levy Itzchak , Maor Yasmin , Mahroum Naim , Olmer Liraz , Wieder Anat , Litchevski Vladislav , Mor Orna , Rahav Galia
Published: November 2016

Objective

To quantify and characterise missed opportunities for earlier HIV diagnosis in patients diagnosed with advanced HIV.

Design

A retrospective observational cohort study.

Setting

A central tertiary medical centre in Israel.

Measures

The proportion of patients with advanced HIV, the proportion of missed opportunities to diagnose them earlier, and the rate of clinical indicator diseases (CIDs) in those patients.

Results

Between 2010 and 2015, 356 patients were diagnosed with HIV, 118 (33.4%) were diagnosed late, 57 (16%) with advanced HIV disease. Old age (OR=1.45 (95% CI 1.16 to 1.74)) and being heterosexual (OR=2.65 (95% CI 1.21 to 5.78)) were significant risk factors for being diagnosed late. All patients with advanced disease had at least one CID that did not lead to an HIV test in the 5 years prior to AIDS diagnosis. The median time between CID and AIDS diagnosis was 24 months (IQR 10–30). 60% of CIDs were missed by a general practitioner and 40% by a specialist.

Conclusions

Missed opportunities to early diagnosis of HIV occur in primary and secondary care. Lack of national guidelines, lack of knowledge regarding CIDs and communication barriers with patients may contribute to a late diagnosis of HIV.
Survey of community pharmacists' perception of electronic cigarettes in London
Authors: Marques Gomes Ana C N , Nabhani-Gebara Shereen , Kayyali Reem , Buonocore Federico , Calabrese Gianpiero
Published: November 2016

Objectives

To seek community pharmacists' perception on use, safety and possible effectiveness of e-cigarettes as quit smoking tools, and their future regulation.

Setting

A survey of a sample of 154 community pharmacies across London, UK.

Context

E-cigarettes have exclusively established themselves in the market through consumers-led demand. To date, e-cigarettes still remain unregulated and can be easily purchased in shops, over the internet, but more controversially also in pharmacies in the UK. Pharmacists find themselves with a shortage of information on their safety and efficacy, and may experience an ethical dilemma when consulted by patients/customers.

Key findings

Response rate: 60% (n=92). Independent pharmacies accounted for 90% of the sample. The majority of participants (73%) sell e-cigarettes. A minority of participants (20%) have been presented with adverse effects such as cough and dry mouth. As possible reasons for their use, pharmacists ranked ‘aid in stop smoking’ as the most important (56%), with ‘cheaper alternative’ (43%) and ‘social/recreational use’ (31%) being the least important ones. Safety issues were raised as statements such as ‘e-liquid in cartridges may be toxic’ were agreed by 52% of respondents. The majority of pharmacists (97%) were supportive of e-cigarettes being regulated, expressing current concerns regarding excipients (42%) and nicotine content (34%). Participants indicated that they would require training in the form of information packs (88%), online tutorials (67%), continuous professional development (CPD) workshops (43%) to cover safety, counselling, dosage instructions, adverse effects and role in the smoking cessation care pathway in the future.

Conclusions

Pharmacists expressed concerns about the safety of e-cigarettes, especially regarding the amounts of excipients and nicotine as these still remain unregulated. Currently, there are no guidelines for pharmacists regarding e-cigarettes. Community pharmacists look forward to regulations so to conduct their duties in a more confident and legislated fashion.
Improving pneumococcal vaccination rates of medical inpatients in urban Nepal using quality improvement measures
Authors: Bock Allison , Chintamaneni Kathan , Rein Lisa , Frazer Tifany , Kayastha Gyan , MacKinney Theodore
Published: November 2016

Streptococcus pneumoniae infection is associated with high morbidity and mortality in low income countries. In Nepal, there is a high lung disease burden and incidence of pneumonia due to multiple factors including indoor air pollution, dust exposure, recurrent infections, and cigarette smoking. Despite the ready availability of effective pneumococcal vaccines (PNV), vaccine coverage rates remain suboptimal globally. Quality Improvement (QI) principles could be applied to improve compliance, but it is a virtually new technology in Nepal.

This QI study for Patan Hospital sought to introduce the concept of QI there, to measure the baseline pneumococcal vaccination rate of qualifying adult patients discharged from the medical wards and to assess reasons for non-vaccination. QI interventions were instituted to improve this rate, measuring the effectiveness of QI methods to produce the desired outcomes using the Model for Improvement, Plan-Do-Study-Change (PDSA) methodology.

In the three week baseline assessment, 2 out of 81 (2%) eligible patients recalled ever receiving a prior pneumococcal vaccine; 68 (84%) unvaccinated patients responded that they were not asked or were unaware of the PNV. After the QI interventions, the pneumococcal vaccination rate significantly increased to 42% (23/56, p<0.001). Post-intervention, the leading reason for non-vaccination was cost (20%, 11/56). Only 5 (9%) unvaccinated patients were not asked or were unaware of the PNV, a significant change in that process outcome from baseline (p<0.001).

Quality improvement measures were effective in increasing pneumococcal vaccination rates, despite the limited familiarity with QI methods at this major teaching hospital. QI techniques may be useful in this and other efforts to improve quality in resource-limited settings, without great cost.
Be(ing) prepared: Guide and Scout participation, childhood social position and mental health at age 50—a prospective birth cohort study
Authors: Dibben Chris , Playford Chris , Mitchell Richard
Published: November 2016

Background

Mental health is a major concern in many countries. We explore whether youth participation in the Scouts and Guides could protect mental health in later life and in particular whether it might reduce inequalities in mental health associated with early life socioeconomic position.

Methods

Using the 1958 birth cohort National Child Development Study, we tested whether Scouts–Guide attendance was associated with mental health (SF-36, Mental Health Index (MHI-5)) controlling for childhood risk factors and interacted with social class.

Results

Of the 9603 cohort members, 28% had participated in the Scouts–Guides. The average MHI-5 score was 74.8 (SD 18.2) at age 50. After adjustment, for potential childhood confounders, participation in Scouts–Guides was associated with a better MHI-5 score of 2.22 (CI 1.32 to 3.08). Among those who had not been a Scout–Guide, there was a gradient in mental health at age 50 by childhood social position, adjusting for other childhood risk factors. This gradient was absent among those who had been a Scout–Guide. Scout–Guides had an 18% lower odds of an MHI-5 score indicative of mood or anxiety disorder. The findings appeared robust to various tests for residual confounding.

Conclusions

Participation in Guides or Scouts was associated with better mental health and narrower mental health inequalities, at age 50. This suggests that youth programmes that support resilience and social mobility through developing the potential for continued progressive self-education, ‘soft’ non-cognitive skills, self-reliance, collaboration and activities in natural environments may be protective of mental health in adulthood.
Two passions, one rewarding job
Authors: Bennett Ashleigh
Published: November 2016

Ashleigh Bennett recently won the White Cross Vets group's Client Care Coordinator award at its annual awards dinner
Prediction and analysis of surface settlement due to shield tunneling for Xi’an Metro
Authors: Zhu Caihui , Li Ning
Published: November 2016

This study describes a new modified prediction method of surface settlement (SS) for Xi’an Metro. The estimation method of SS and its characteristic parameters, volume loss (VL), maximal SS, and settlement trough width (STW) are reviewed and discussed in this paper. The gap parameter (GP) is applied to estimate VL; however, the calculation method of GP and its influence factors have not been clarified entirely. In this study, six influence factors are introduced into the new GP model, and the detailed solutions are presented. This estimation method is able to take into account the support pressure of the shield head at the tunnel face, the lining support pressure around the tunnel opening, the filling effect of tail grouting, yawing, and pitching of the shielding machine, and the long-term deformation of the remoulded surrounding soil. Based on Xi’an Metro line 2, the soil behaviors and measured SS characteristics are deeply investigated. The upper and lower bounds of the total GP of the 15 cases are predicted. Comparison of the predicted SS troughs with field observations can show reasonable agreement. It is suggested that the new estimation method can be used effectively in estimating the SS induced by the shield tunneling method.
Simple mass estimates for resonance(s) being 6 top + 6 antitop bound states and combinations thereof
Authors: Nielsen H. B.
Published: November 2016

We have long speculated,[Formula: see text] that 6 top + 6 antitop quarks due to the relatively large size of the top-Yukawa coupling would bind exceptionally strongly by mainly Higgs exchange. Here we present a surprisingly simple “calculation” of the mass of this speculated bound state. Even a possible resonance in scattering of two such bound states is speculated. For the “calculation” of the masses it is crucial to assume, that our since long speculated principle “multiple point principle,”[Formula: see text] is true. This principle says: there are several vacua all having almost zero energy density. Further, we make an approximation of the Higgs Yukawa potential essentially replacing the exponential in it by a step-function. The new result means that there are now two independent calls for our bound state having the mass around 750 GeV required by our “new law of nature” the Multiple Point Principle. It should be remarked that in our picture there is no new physics in the sense of new fundamental particles, but the “multiple point principle” is new in the sense of being not yet accepted. Further, we get the same mass within uncertainties as earlier2 but now from a completely different assumption, except for being from our “multiple point principle.” But the two masses are gotten from using different (speculative) vacua occurring in the pure Standard Model.
Dipolar quantization and the infinite circumference limit of two-dimensional conformal field theories
Authors: Ishibashi Nobuyuki , Tada Tsukasa
Published: November 2016

Elaborating on our previous presentation, where the term dipolar quantization was introduced, we argue here that adopting [Formula: see text] as the Hamiltonian instead of [Formula: see text] yields an infinite circumference limit in two-dimensional conformal field theory. The new Hamiltonian leads to dipolar quantization instead of radial quantization. As a result, the new theory exhibits a continuous and strongly degenerated spectrum in addition to the Virasoro algebra with a continuous index. Its Hilbert space exhibits a different inner product than that obtained in the original theory. The idiosyncrasy of this particular Hamiltonian is its relation to the so-called sine-square deformation, which is found in the study of a certain class of quantum statistical systems. The appearance of the infinite circumference explains why the vacuum states of sine-square deformed systems are coincident with those of the respective closed-boundary systems.
A Hybrid Method for Modeling and Solving Supply Chain Optimization Problems with Soft and Logical Constraints
Authors: Sitek Paweł , Bzdyra Krzysztof , Wikarek Jarosław
Published: November 2016

This paper presents a hybrid method for modeling and solving supply chain optimization problems with soft, hard, and logical constraints. Ability to implement soft and logical constraints is a very important functionality for supply chain optimization models. Such constraints are particularly useful for modeling problems resulting from commercial agreements, contracts, competition, technology, safety, and environmental conditions. Two programming and solving environments, mathematical programming (MP) and constraint logic programming (CLP), were combined in the hybrid method. This integration, hybridization, and the adequate multidimensional transformation of the problem (as a presolving method) helped to substantially reduce the search space of combinatorial models for supply chain optimization problems. The operation research MP and declarative CLP, where constraints are modeled in different ways and different solving procedures are implemented, were linked together to use the strengths of both. This approach is particularly important for the decision and combinatorial optimization models with the objective function and constraints, there are many decision variables, and these are summed (common in manufacturing, supply chain management, project management, and logistic problems). TheECLiPSesystem with Eplex library was proposed to implement a hybrid method. Additionally, the proposed hybrid transformed model is compared with the MILP-Mixed Integer Linear Programming model on the same data instances. For illustrative models, its use allowed finding optimal solutions eight to one hundred times faster and reducing the size of the combinatorial problem to a significant extent.
Bariatric Surgery, Polycystic Ovary Syndrome, and Infertility
Authors: Butterworth James , Deguara Jean , Borg Cynthia-Michelle
Published: November 2016

Background. Polycystic ovary syndrome (PCOS) is the commonest cause of female infertility. Visceral obesity and insulin resistance are key pathophysiological mechanisms behind PCOS. Women suffering from this syndrome and infertility often seek bariatric surgery hoping that they would be able to conceive postoperatively. Objective. At present, there is no consensus on the role of bariatric surgery in the management of PCOS-associated infertility within the medical community, making it difficult to give specific advice to these women, so a review of the literature was necessary. Results. A detailed review of the literature was performed. Only 6 manuscripts were relevant and contained quantitative data. They demonstrated that bariatric surgery results in postoperative conception rates varying from 33% to 100%. Surgery is also associated with amelioration of menstrual irregularities, hormonal abnormalities, and hirsutism that are associated with PCOS. These studies were retrospective and only had a small number of participants with infertility. Conclusions. Bariatric surgery has been shown to conclusively improve life expectancy, quality of life, and comorbidities like type 2 diabetes and obstructive sleep apnea. However, further research is required to identify whether weight loss surgery results in significant improvement in fertility of women with PCOS and to investigate which operation has the best results.
Elevated Plasma Endothelin-1 Levels in Normal Tension Glaucoma and Primary Open-Angle Glaucoma: A Meta-Analysis
Authors: Li Shengjie , Zhang Aiping , Cao Wenjun , Sun Xinghuai
Published: November 2016

Purpose. The aim of this meta-analysis was to clarify the association between the plasma endothelin-1 level and the risks of normal tension glaucoma (NTG) and primary open-angle glaucoma (POAG). Methods. Relevant publications were collected from three databases including PubMed, EMBASE, and the Web of Science through December 31, 2015. In this study, the terms “(endothelin OR ET) AND glaucoma” were searched. Review Manager 5.2 was used to process the data. Results. Seven studies (212 cases, 164 controls) were included for the NTG analysis. The mean plasma endothelin-1 level in the NTG subjects was 0.60 pg/mL (p=0.02, 95% CI: 0.17–1.04) higher than that of the healthy controls. Six studies (160 cases, 174 controls) were included for the POAG analysis, and the endothelin-1 level was 0.63 pg/mL (p=0.007, 95% CI: 0.12–1.15) higher in the POAG subjects than in the healthy controls. Additionally, two studies influenced the meta-analysis results regarding the association of plasma endothelin-1 with POAG by sensitivity analysis, and the probability of publication bias was low. Conclusions. The observation that NTG and POAG subjects showed significantly elevated endothelin-1 plasma concentrations suggests that a higher plasma level of endothelin-1 might increase the risk of NTG and POAG development.
Impact of Lifestyle Intervention on HDL-Induced eNOS Activation and Cholesterol Efflux Capacity in Obese Adolescent
Authors: Wesnigk Jenny , Bruyndonckx Luc , Hoymans Vicky Y. , De Guchtenaere Ann , Fischer Tina , Schuler Gerhard , Vrints Christiaan J. , Adams Volker
Published: November 2016

Background. Endothelial dysfunction occurs in obese children and adolescent and is regarded as a key step in the development of atherosclerosis. Important components for the development of endothelial dysfunction are reduced activity of endothelial nitric oxide synthase (eNOS) and an increase in cholesterol deposition in the vessel wall, due to reduced reverse cholesterol transport (RCT) activity. High density lipoprotein (HDL) exhibits antiatherosclerotic properties including modulation of eNOS activity and cholesterol efflux capacity. Lifestyle intervention programs can modify endothelial dysfunction in obese adolescents, but their impact on HDL-mediated eNOS activation and RCT is unknown so far. Methods. Obese adolescents (15±1 years, BMI > 35 kg/m2) where randomized either to an intervention group (IG, n=8; restricted diet and exercise) or to a usual care group (UC, n=8). At the beginning and after 10 months of treatment HDL-mediated eNOS phosphorylation and cholesterol efflux capacity were evaluated. Results. Ten months of treatment resulted in a substantial weight loss (−31%), an improvement of endothelial function, and an increase in HDL-mediated eNOS-Ser1177 phosphorylation and RCT. A correlation between change in eNOS-Ser1177 phosphorylation or RCT and change in endothelial function was noted. Conclusion. A structured lifestyle intervention program improves antiatherosclerotic HDL functions, thereby positively influencing endothelial function.
A GRASP for Next Generation Sapphire Image Acquisition Scheduling
Authors: Wang Yang , Mitrovic Minic Snezana , Leitch Robert , Punnen Abraham P.
Published: November 2016

This paper investigates an image acquisition scheduling problem for a Canadian surveillance-of-space satellite named Sapphire that takes images of deep space Earth-orbiting objects. For a set of resident space objects (RSOs) that needs to be imaged within the time horizon of one day, the Sapphire image acquisition scheduling (SIAS) problem is to find a schedule that maximizes the “Figure of Merit” of all the scheduled RSO images. To address the problem, we propose an effective GRASP heuristic that alternates between a randomized greedy constructive procedure and a local search procedure. Experimental comparisons with the currently used greedy algorithm are presented to demonstrate the merit of the proposed algorithm in handling the SIAS problem.
Integrodifferential Inequalities Arising in the Theory of Differential Equations
Authors: Khan Zareen A.
Published: November 2016

The goal of this paper is to achieve some new results related to integrodifferential inequalities of one independent variable which can be applied as a study of qualitative and quantitative properties of solutions of some nonlinear integral equations.
Targeted Inhibition of the miR‐199a/214 Cluster by CRISPR Interference Augments the Tumor Tropism of Human Induced Pluripotent Stem Cell‐Derived Neural Stem Cells under Hypoxic Condition
Authors: Luo Yumei , Xu Xuehu , An Xiuli , Sun Xiaofang , Wang Shu , Zhu Detu
Published: November 2016

The human induced pluripotent stem cell (hiPSC) provides a breakthrough approach that helps overcoming ethical and allergenic challenges posed in application of neural stem cells (NSCs) in targeted cancer gene therapy. However, the tumor‐tropic capacity of hiPSC‐derived NSCs (hiPS‐NSCs) still has much room to improve. Here we attempted to promote the tumor tropism of hiPS‐NSCs by manipulating the activity of endogenous miR‐199a/214 cluster that is involved in regulation of hypoxia‐stimulated cell migration. We first developed a baculovirus‐delivered CRISPR interference (CRISPRi) system that sterically blocked the E‐box element in the promoter of the miR‐199a/214 cluster with an RNA‐guided catalytically dead Cas9 (dCas9). We then applied this CRISPRi system to hiPS‐NSCs and successfully suppressed the expression of miR‐199a‐5p, miR‐199a‐3p, and miR‐214 in the microRNA gene cluster. Meanwhile, the expression levels of their targets related to regulation of hypoxia‐stimulated cell migration, such as HIF1A, MET, and MAPK1, were upregulated. Further migration assays demonstrated that the targeted inhibition of the miR‐199a/214 cluster significantly enhanced the tumor tropism of hiPS‐NSCs both in vitro and in vivo. These findings suggest a novel application of CRISPRi in NSC‐based tumor‐targeted gene therapy.
Profiling of the Predicted Circular RNAs in Ductal In Situ and Invasive Breast Cancer: A Pilot Study
Authors: Galasso Marco , Costantino Giorgio , Pasquali Lorenzo , Minotti Linda , Baldassari Federica , Corrà Fabio , Agnoletto Chiara , Volinia Stefano
Published: November 2016

The recent advantage obtained by next generation sequencing allows a depth investigation of a new “old” kind of noncoding transcript, the circular RNAs. Circular RNAs are nontranslated RNAs, typically nonpolyadenylated, with a resistance to exonucleases that gives them the ability to be more stable than the common linear RNA isoforms. We used a bioinformatic detection tool (CIRCexplorer) to research predictive circRNAs from the next generation sequenced data of five samples of ductal in situ carcinoma (DCIS) and matched adjacent invasive ductal carcinoma (IDC). Furthermore, we also investigated the circular RNAs expressed in MCF7, an invasive breast ductal carcinoma cell line. We described the genomic context of the predicted circular RNAs and we address the hypothetical possible functional roles. This study showed a perspective of a panel of predictive circRNAs identified and the function that circRNAs could exert.
Optical Simulation and Experimental Verification of a Fresnel Solar Concentrator with a New Hybrid Second Optical Element
Authors: Li Guiqiang , Jin Yi
Published: November 2016

Fresnel solar concentrator is one of the most common solar concentrators in solar applications. For high Fresnel concentrating PV or PV/T systems, the second optical element (SOE) is the key component for the high optical efficiency at a wider deflection angle, which is important for overcoming unavoidable errors from the tacking system, the Fresnel lens processing and installment technology, and so forth. In this paper, a new hybrid SOE was designed to match the Fresnel solar concentrator with the concentration ratio of 1090x. The ray-tracing technology was employed to indicate the optical properties. The simulation outcome showed that the Fresnel solar concentrator with the new hybrid SOE has a wider deflection angle scope with the high optical efficiency. Furthermore, the flux distribution with different deviation angles was also analyzed. In addition, the experiment of the Fresnel solar concentrator with the hybrid SOE under outdoor condition was carried out. The verifications from the electrical and thermal outputs were all made to analyze the optical efficiency comprehensively. The optical efficiency resulting from the experiment is found to be consistent with that from the simulation.
Calcium Oxalate Induces Renal Injury through Calcium‐Sensing Receptor
Authors: Li Xiaoran , Ma Junhai , Shi Wei , Su Yu , Fu Xu , Yang Yanlin , Lu Jianzhong , Yue Zhongjin
Published: November 2016

Objective. To investigate whether calcium‐sensing receptor (CaSR) plays a role in calcium‐oxalate‐induced renal injury. Materials and Methods. HK‐2 cells and rats were treated with calcium oxalate (CaOx) crystals with or without pretreatment with the CaSR‐specific agonist gadolinium chloride (GdCl3) or the CaSR‐specific antagonist NPS2390. Changes in oxidative stress (OS) in HK‐2 cells and rat kidneys were assessed. In addition, CaSR, extracellular signal‐regulated protein kinase (ERK), c‐Jun N‐terminal protein kinase (JNK), and p38 expression was determined. Further, crystal adhesion assay was performed in vitro, and the serum urea and creatinine levels and crystal deposition in the kidneys were also examined. Results. CaOx increased CaSR, ERK, JNK, and p38 protein expression and OS in vitro and in vivo. These deleterious changes were further enhanced upon pretreatment with the CaSR agonist GdCl3 but were attenuated by the specific CaSR inhibitor NPS2390 compared with CaOx treatment alone. Pretreatment with GdCl3 further increased in vitro and in vivo crystal adhesion and renal hypofunction. In contrast, pretreatment with NPS2390 decreased in vitro and in vivo crystal adhesion and renal hypofunction. Conclusions. CaOx‐induced renal injury is related to CaSR‐mediated OS and increased mitogen‐activated protein kinase (MAPK) signaling, which subsequently leads to CaOx crystal adhesion.
Fracture Resistance of K3 Nickel-Titanium Files Made from Different Thermal Treatments
Authors: Choi JinWook , Oh Soram , Kim Yu-Chan , Jee Kwang-Koo , Kum KeeYeon , Chang SeokWoo
Published: November 2016

The purpose of this study was to compare fracture resistances of K3 nickel-titanium files made from different thermal treatments. K3 (SybronEndo, Orange, CA), K3XF (SybronEndo), and experimentally heat treated K3 (K3H) were used. For the cyclic fatigue test, the samples were rotated with up-and-down motion in the artificial canal with the curvature of 60 degrees until the fracture occurred. The number of cycles to fracture (NCF) was measured. For the torsional fracture test, the samples were tightly bound and rotated until the fracture occurred. Elastic modulus (EM), ultimate torsional strength (UTS), and angle of rotation to fracture (ARF) were measured. The results were statistically analyzed by one-way ANOVA. The NCF of K3H was higher than those of K3 and K3XF (P<0.05). The EM of K3XF and K3H was lower than that of K3 (P<0.05). There was no significant difference in UTS. The ARF of K3XF was higher than that of K3 (P<0.05). K3XF and K3H showed more flexibility than K3. The maximum torsional angle of K3XF was higher than that of K3, but there was no significant difference on the UTS in all three groups.
Effect of Low-Pressurized Perfusion with Different Concentration of Elastase on the Aneurysm Formation Rate in the Abdominal Aortic Aneurysm Model in Rabbits
Authors: Nie Maoxiao , Yan Yunfeng , Li Xinhe , Feng Tingting , Zhao Xin , Zhang Mingduo , Zhao Quanming
Published: November 2016

Establishing an animal model of abdominal aortic aneurysm (AAA) is the key to study the pathogenesis and the pathophysiological features of AAAs. We investigated the effects of low-pressurized perfusion with different concentrations of elastase on aneurysm formation rate in the AAA model. Fifty male New Zealand white rabbits were randomly divided into A, B, C, D, and E groups. 10 μL of normal saline was perfused into the abdominal aorta in group A and 1 U/mL, 10 U/mL, 100 U/mL, or 200 U/mL of elastase was, respectively, perfused for the other four groups. All the animals were perfused for 7 min. Doppler ultrasound examinations of the abdominal aorta were performed before surgery and on day 14 after surgery. The rabbits were sacrificed and the perfused segment of the abdominal aorta was observed visually and after staining. The aneurysm formation rate of group A, group B, group C, group D, and group E was, respectively, 0%, 0%, 33.3%, 102.5–146.8%, and 241.5–255.2%. The survival rate of five groups was 90%, 90%, 90%, 90%, and 40%, respectively. So, we concluded that low-pressurized perfusion with 100 U/mL of elastase can effectively establish AAAs in rabbits with a high aneurysm formation rate.
IL-6 Promotes Islet β-Cell Dysfunction in Rat Collagen-Induced Arthritis
Authors: Jin Huan , Ning Yaogui , Zhou Haotong , Wang Youlian
Published: November 2016

The aim of this study was to explore the possible mechanism of rheumatoid arthritis- (RA-) related abnormal glucose metabolism. The model of collagen-induced arthritis (CIA) was established by intradermal injection of type II collagen into Wistar rats; complete Freund’s adjuvant injections were used as the control group. Fasting plasma glucose (FBG) was measured by the glucose oxidase method. Fasting insulin (FIns) and the expressions of IL-6 were detected by ELISA. Islet caspase-3 was examined by immunohistochemistry. On day 17 after immunization, FBG of the CIA group showed an elevated FBG value compared with the control group. Meanwhile, the FIns of group CIA was lower when compared with the control group. Interestingly, the inflammatory cytokine IL-6 expression was significantly increased when compared with the control group. As expected, the abnormal glucose metabolism was accompanied by the increased IL-6 expression. Furthermore, in line with the upregulated IL-6 expression, the apoptosis related enzyme caspase-3 was also markedly increased. These data showed that the elevated FBG in CIA may be associated with the reduced FIns level secondary to the overapoptosis of pancreas islet cells induced by IL-6.
Bioinformatics Analysis of the Human Surfaceome Reveals New Targets for a Variety of Tumor Types
Authors: Fonseca André L. , da Silva Vandeclécio L. , da Fonsêca Marbella M. , Meira Isabella T. J. , da Silva Thayná E. , Kroll José E. , Ribeiro-dos-Santos André M. , Freitas Cléber R. , Furtado Raimundo , de Souza Jorge E. , Stransky Beatriz , de Souza Sandro J.
Published: November 2016

It is estimated that 10 to 20% of all genes in the human genome encode cell surface proteins and due to their subcellular localization these proteins represent excellent targets for cancer diagnosis and therapeutics. Therefore, a precise characterization of the surfaceome set in different types of tumor is needed. Using TCGA data from 15 different tumor types and a new method to identify cancer genes, the S-score, we identified several potential therapeutic targets within the surfaceome set. This allowed us to expand a previous analysis from us and provided a clear characterization of the human surfaceome in the tumor landscape. Moreover, we present evidence that a three-gene set—WNT5A, CNGA2, and IGSF9B—can be used as a signature associated with shorter survival in breast cancer patients. The data made available here will help the community to develop more efficient diagnostic and therapeutic tools for a variety of tumor types.