bluuebunny/crossref_metadata_2025 huggingface dataset:
Calculating the Prior Probability Distribution for a Causal Network Using Maximum Entropy: Alternative Approaches
Authors: Markham Michael J.
Published: September 2011

Some problems occurring in Expert Systems can be resolved by employing a causal (Bayesian) network and methodologies exist for this purpose. These require data in a specific form and make assumptions about the independence relationships involved. Methodologies using Maximum Entropy (ME) are free from these conditions and have the potential to be used in a wider context including systems consisting of given sets of linear and independence constraints, subject to consistency and convergence. ME can also be used to validate results from the causal network methodologies. Three ME methods for determining the prior probability distribution of causal network systems are considered. The first method is Sequential Maximum Entropy in which the computation of a progression of local distributions leads to the over-all distribution. This is followed by development of the Method of Tribus. The development takes the form of an algorithm that includes the handling of explicit independence constraints. These fall into two groups those relating parents of vertices, and those deduced from triangulation of the remaining graph. The third method involves a variation in the part of that algorithm which handles independence constraints. Evidence is presented that this adaptation only requires the linear constraints and the parental independence constraints to emulate the second method in a substantial class of examples.
Universal Property of Quantum Gravity implied by Uniqueness Theorem of Bekenstein-Hawking Entropy
Authors: Saida Hiromi
Published: September 2011

This paper consists of three parts. In the first part, we prove that the Bekenstein-Hawking entropy is the unique expression of black hole entropy. Our proof is constructed in the framework of thermodynamics without any statistical discussion. In the second part, intrinsic properties of quantum mechanics are shown, which justify the Boltzmann formula to yield a unique entropy in statistical mechanics. These properties clarify three conditions, one of which is necessary and others are sufficient for the validity of Boltzmann formula. In the third part, by combining the above results, we find a reasonable suggestion from the sufficient conditions that the potential of gravitational interaction among microstates of underlying quantum gravity may not diverge to negative infinity (such as Newtonian gravity) but is bounded below at a finite length scale. In addition to that, from the necessary condition, the interaction has to be repulsive within the finite length scale. The length scale should be Planck size. Thus, quantum gravity may become repulsive at Planck length. Also, a relation of these suggestions with action integral of gravity at semi-classical level is given. These suggestions about quantum gravity are universal in the sense that they are independent of any existing model of quantum gravity.
Assessing Seven Decades of Carbon Accumulation in Two U.S. Northern Hardwood Forests
Authors: Hoover Coeli M.
Published: September 2011

Forests play a key role in the global carbon cycle, and programs aimed at mitigating greenhouse gas emissions through the protection and enhancement of forest carbon stocks are growing in number. Adding greenhouse gas mitigation as a management objective presents managers with a considerable challenge, because data and guidelines are scarce. Long-term inventory datasets have the potential to serve as a useful resource, providing data on carbon accumulation over time, as well as offering insight on strategies for managing forests for the objective of climate mitigation in the face of changing climate and disturbance regimes. We present long-term estimates of carbon accumulation developed from biometric measurements from two northern hardwood forests in the northeastern USA. The Bartlett Experimental Forest in central New Hampshire, USA, stored an estimated net average annual 0.53 tC/ha/yr between 1932–2001, for an increase of 50% in carbon stock per unit area; there were significant differences in accrual rates between age classes (38% for old unmanaged stands and 78% for younger unmanaged stands). The Kane Experimental Forest in northwestern Pennsylvania, USA, exhibited a 140% increase in carbon stored per unit area between 1932 and 2006, with an average annual accumulation rate of 0.89 tC/ha/yr. While both forests have experienced management activity and natural disturbances and differ in species composition, the average age of the forests is an important factor driving the differences in net accumulation rates.
Acid-Denatured Green Fluorescent Protein (GFP) as Model Substrate to Study the Chaperone Activity of Protein Disulfide Isomerase
Authors: Mares Rosa E. , Meléndez-López Samuel G. , Ramos Marco A.
Published: September 2011

Green fluorescent protein (GFP) has been widely used in several molecular and cellular biology applications, since it is remarkably stable in vitro and in vivo. Interestingly, native GFP is resistant to the most common chemical denaturants; however, a low fluorescence signal has been observed after acid-induced denaturation. Furthermore, this acid-denatured GFP has been used as substrate in studies of the folding activity of some bacterial chaperones and other chaperone-like molecules. Protein disulfide isomerase enzymes, a family of eukaryotic oxidoreductases that catalyze the oxidation and isomerization of disulfide bonds in nascent polypeptides, play a key role in protein folding and it could display chaperone activity. However, contrasting results have been reported using different proteins as model substrates. Here, we report the further application of GFP as a model substrate to study the chaperone activity of protein disulfide isomerase (PDI) enzymes. Since refolding of acid-denatured GFP can be easily and directly monitored, a simple micro-assay was used to study the effect of the molecular participants in protein refolding assisted by PDI. Additionally, the effect of a well-known inhibitor of PDI chaperone activity was also analyzed. Because of the diversity their functional activities, PDI enzymes are potentially interesting drug targets. Since PDI may be implicated in the protection of cells against ER stress, including cancer cells, inhibitors of PDI might be able to enhance the efficacy of cancer chemotherapy; furthermore, it has been demonstrated that blocking the reductive cleavage of disulfide bonds of proteins associated with the cell surface markedly reduces the infectivity of the human immunodeficiency virus. Although several high-throughput screening (HTS) assays to test PDI reductase activity have been described, we report here a novel and simple micro-assay to test the chaperone activity of PDI enzymes, which is amenable for HTS of PDI inhibitors.
The Important Molecular Markers on Chromosome 17 and Their Clinical Impact in Breast Cancer
Authors: Zhang Wei , Yu Yingyan
Published: September 2011

Abnormalities of chromosome 17 are important molecular genetic events in human breast cancers. Several famous oncogenes (HER2, TOP2A and TAU), tumor suppressor genes (p53, BRCA1 and HIC-1) or DNA double-strand break repair gene (RDM1) are located on chromosome 17. We searched the literature on HER2, TOP2A, TAU, RDM1, p53, BRCA1 and HIC-1 on the Pubmed database. The association of genes with chromosome 17, biological functions and potential significance are reviewed. In breast cancer, the polysomy 17 (three or more) is the predominant numerical aberration. HER2 amplification is widely utilized as molecular markers for trastuzumab target treatment. Amplified TOP2A, TAU and RDM1 genes are related to a significant response to anthracycline-based chemotherapy, taxane or cisplatin, respectively. In contrast, p53, BRCA1 and HIC-1 are important tumor suppressor genes related to breast carcinogenesis. This review focused on several crucial molecular markers residing on chromosome 17. The authors consider the somatic aberrations of chromosome 17 and associated genes in breast cancer.
Molecular Biomarkers for the Diagnosis of Primary Vitreoretinal Lymphoma
Authors: Wang Yujuan , Shen Defen , Wang Vinson M. , Sen H. Nida , Chan Chi-Chao
Published: September 2011

Primary vitreoretinal lymphoma (PVRL) or primary intraocular lymphoma, a subtype of primary central nervous system lymphoma, often masquerades as uveitis. The diagnosis of PVRL requires identification of lymphoma cells inside the eye, which is often challenging due to the frequent necrosis and admixing of PVRL cells with reactive lymphocytes. Therefore, detection of immunoglobulin heavy chain (IgH) and T-cell receptor (TCR) gene rearrangements provide molecular diagnosis of B- and T-cell lymphoma, respectively. We retrospectively evaluated 208 cases with a clinical diagnosis of masquerade syndrome from 1998 to 2010. In 200 cases with molecular analyses using microdissection and polymerase chain reaction, we found that 110 cases had IgH gene rearrangement, 5 cases had TCR gene rearrangement, and 85 cases were negative for these two gene arrangements. The molecular data corroborated the cytopathological diagnoses of PVRL and uveitis in the majority of cases. Cytokine above the detected levels in the specimens were also measured in 80 of the 208 cases. A ratio of vitreous IL-10 to IL-6 greater than 1, suggesting PVRL, was found in 56/80 cases; 53/56 had the correct diagnosis. A ratio less than 1, suggesting uveitis, was found in 24/80 cases; 17/24 correctly confirmed the diagnosis. Moreover, the molecular data corresponded well with the clinical course of the diseases. The sensitivity and specificity of these molecular biomarkers for the diagnosis of PVRL are higher than 95%.
Isolation and Characterization of Microsatellite Loci for Hibiscus aridicola (Malvaceae), an Endangered Plant Endemic to the Dry-Hot Valleys of Jinsha River in Southwest China
Authors: Zhang Le , Sun Weibang , Wang Zhonglang , Guan Kaiyun , Yang Junbo
Published: September 2011

Hibiscus aridicola (Malvaceae) is an endangered ornamental shrub endemic to the dry-hot valleys of Jinsha River in southwest China. Only four natural populations of H. aridicola exist in the wild according to our field investigation. It can be inferred that H. aridicola is facing a very high risk of extinction in the wild and an urgent conservation strategy is required. By using a modified biotin-streptavidin capture method, a total of 40 microsatellite markers were developed and characterized in H. aridicola for the first time. Polymorphisms were evaluated in 39 individuals from four natural populations. Fifteen of the markers showed polymorphisms with two to six alleles per locus; the observed heterozygosity ranged from 0.19 to 0.72. These microsatellite loci would be useful tools for population genetics studies on H. aridicola and other con-generic species which are important to the conservation and development of endangered species.
KCNQ1 Haplotypes Associate with Type 2 Diabetes in Malaysian Chinese Subjects
Authors: Saif-Ali Riyadh , Ismail Ikram S. , Al-Hamodi Zaid , Al-Mekhlafi Hesham M. , Siang Lee C. , Alabsi Aied M. , Muniandy Sekaran
Published: September 2011

The aim of this study was to investigate the association of single nucleotide polymorphisms (SNPs) and haplotypes of potassium voltage-gated channel, KQT-like subfamily, member 1 (KCNQ1) with type 2 diabetes (T2D) in Malaysian Chinese subjects. The KCNQ1 SNPs rs2237892, rs2283228 and rs2237895 were genotyped in 300 T2D patients and 230 control subjects without diabetes and metabolic syndrome. Two logistic regression models of analysis were applied, the first adjusted for age and gender while the second adjusted for age, gender and body mass index. The additive genetic analysis showed that adjusting for body mass index (BMI) even strengthened association of rs2237892, rs2283228 and rs2237895 with T2D (OR = 2.0, P = 5.1 × 10−5; OR = 1.9, P = 5.2 × 10−5; OR = 1.9, P = 7.8 × 10−5, respectively). The haplotype TCA containing the allele of rs2237892 (T), rs2283228 (C) and rs2237895 (A) was highly protective against T2D (Second model; OR = 0.17, P = 3.7 × 10−11). The KCNQ1 rs2237892 (TT), and the protective haplotype (TCA) were associated with higher beta-cell function (HOMA-B) in normal subjects (P = 0.0002; 0.014, respectively). This study found that KCNQ1 SNPs was associated with T2D susceptibility in Malaysian Chinese subjects. In addition, certain KCNQ1 haplotypes were strongly associated with T2D.
2,3-Diaminophenazine
Authors: Zhou Pandeng , Liu Hao , Chen Shicheng , Lucia Lucian , Zhan Huaiyu , Fu Shiyu
Published: September 2011

Herein, we synthesized 2,3-diaminophenazine (DAP) from o-phenylenediamine (OP) using fungal laccase as a biocatalyst. The conversion ratio of OP monomer was 85% and the yield of the final purified product, DAP, was 63%. The structure of the main product, DAP, was confirmed by using several spectroscopy techniques (UV-VIS, IR, 2D-NMR, and MS).
Characterization of a Novel Serine Protease Inhibitor Gene from a Marine Metagenome
Authors: Jiang Cheng-Jian , Hao Zhen-Yu , Zeng Rong , Shen Pei-Hong , Li Jun-Fang , Wu Bo
Published: September 2011

A novel serine protease inhibitor (serpin) gene designated as Spi1C was cloned via the sequenced-based screening of a metagenomic library from uncultured marine microorganisms. The gene had an open reading frame of 642 base pairs, and encoded a 214-amino acid polypeptide with a predicted molecular mass of about 28.7 kDa. The deduced amino acid sequence comparison and phylogenetic analysis indicated that Spi1C and some partial proteinase inhibitor I4 serpins were closely related. Functional characterization demonstrated that the recombinant Spi1C protein could inhibit a series of serine proteases. The Spi1C protein exhibited inhibitory activity against α-chymotrypsin and trypsin with Ki values of around 1.79 × 10−8 and 1.52 × 10−8 M, respectively. No inhibition activity was exhibited against elastase. Using H-D-Phe-Pip-Arg-pNA as the chromogenic substrate, the optimum pH and temperature of the inhibition activity against trypsin were 7.0–8.0 and 25 °C, respectively. The identification of a novel serpin gene underscores the potential of marine metagenome screening for novel biomolecules.
Evolution of Morphology and Microstructure in Electrodeposited Nanocrystalline Al–Mg Alloy Dendrites
Authors: Tatiparti Sankara Sarma V. , Ebrahimi Fereshteh
Published: September 2011

Nanocrystalline Al–Mg dendrites were fabricated through galvanostatic electrodeposition. Initially feather-like morphology was formed exhibiting morphological evolution to smooth globules at its tips. With eventual deposition, rough globules formed over the smooth ones. The feather-like and smooth globules possessed supersaturated face centered cubic (fcc)–Al(Mg) phase with ~7 and ~20 at.% Mg respectively. The rough globules contained hexagonal close packed (hcp)–Mg(Al) phase with ~80 at.% Mg. Microstructural examinations revealed that the feather-like and rough globules possessed grain sizes of ~42 ± 15 and ~36 ± 12 nm respectively. The region, which exhibited morphological evolution from feather-like to smooth globules, possessed ~16 ± 7 nm grain size. The observed microstructural and compositional features were attributed to the local current density values. The formation of the Al–Mg dendrites is discussed in this paper.
Synthetic Organic Electrochemistry in Ionic Liquids: The Viscosity Question
Authors: Bornemann Steven , Handy Scott T.
Published: September 2011

Ionic liquids are obvious candidates for use in electrochemical applications due to their ionic character. Nevertheless, relatively little has been done to explore their application in electrosynthesis. We have studied the Shono oxidation of arylamines and carbamates using ionic liquids as recyclable solvents and have noted that the viscosity of the medium is a major problem, although with the addition of sufficient co-solvent, good results and excellent recovery and recycling of the ionic liquid can be achieved.
Antioxidant, Anti-Lipoxygenase and Cytotoxic Activity of Leptadenia pyrotechnica (Forssk.) Decne Polyphenolic Constituents
Authors: Khasawneh Mohammad A. , Elwy Hanan M. , Hamza Alaaeldin A. , Fawzi Nael M. , Hassan Ahmed H.
Published: September 2011

Leptadenia pyrotechnica Forssk is a traditional medicinal herb used for treatment of inflammatory diseases and cancer. In this research, the aqueous ethanolic crude extract of Leptadenia pyrotechnica aerial parts, along with its ethyl acetate, n-butanol and water partitioning fractions were evaluated for their antioxidant capacity, polyphenolic content, anti-inflammatory and anti-cancer properties. The total antioxidant capacity was estimated by the FRAP, DPPH, ABTS and β-carotene bleaching assays.The ethyl acetate fraction exhibited the highest polyphenolic content (252.27 mg gallic acid/g) and the best antioxidant activity (1.2, 0.57, 0.45 mmol ascorbic acid equivalent/g in the FRAP, ABTS and DPPH assays, respectively). Furthermore, the same extract showed appreciable anti-inflammatory via lipoxygenase (LOX) inhibitory activity (IC50 = 1.41 µg/mL). Moreover, the ethyl acetate fraction also showed the strongest cytotoxic effect (IC50 = 43.16 µg/mL) against MCF-7 human breast cancer cell line. These results suggest that this plant may be considered an interesting source of compounds with antioxidant, anti-inflammatory and anti-cancer properties for therapeutic, nutraceutical and functional food applications.
Recent Advances in Microflow Photochemistry
Authors: Oelgemöller Michael , Shvydkiv Oksana
Published: September 2011

This review summarizes recent advances in microflow photochemical technologies and transformations. The portfolio of reactions comprises homogeneous and heterogeneous types, among them photoadditions, photorearrangements, photoreductions, photodecarboxylations, photooxygenations and photochlorinations. While microflow photochemistry is most commonly employed as a micro-scale synthesis tool, scale-up and technical production processes have already been developed.
Synthesis and SAR Study of Novel Peptide Aldehydes as Inhibitors of 20S Proteasome
Authors: Ma Yuheng , Xu Bo , Fang Yuan , Yang Zhenjun , Cui Jingrong , Zhang Liangren , Zhang Lihe
Published: September 2011

Based on the analysis of the crystal structure of MG101 (1) and 20S proteasomes, a new series of peptide aldehyde derivatives were designed and synthesized. Their ability to inhibit 20S proteasome was assayed. Among them, Cbz-Glu(OtBu)-Phe-Leucinal (3c), Cbz-Glu(OtBu)-Leu-Leucinal (3d), and Boc-Ser(OBzl)-Leu-Leucinal (3o) exhibited the most activity, which represented an order of magnitude enhancement compared with MG132 (2). The covalent docking protocol was used to explore the binding mode. The structure-activity relationship of the peptide aldehyde inhibitors is discussed.
1,3-Substituted Imidazolidine-2,4,5-triones: Synthesis and Inhibition of Cholinergic Enzymes
Authors: Pejchal Vladimir , Stepankova Sarka , Padelkova Zdenka , Imramovsky Ales , Jampilek Josef
Published: September 2011

A series of novel and highly active acetylcholinesterase and butyrylcholinesterase inhibitors derived from substituted benzothiazoles containing an imidazolidine-2,4,5-trione moiety were synthesized and characterized. The molecular structure of 1-(2,6-diisopropyl-phenyl)-3-[(1R)-1-(6-fluoro-1,3-benzothiazol-2-yl)ethyl]-imidazolidine-2,4,5-trione (3g) was determined by single-crystal X-ray diffraction. Both optical isomers are present as two independent molecules in the triclinic crystal system. The lipophilicity of the compounds was determined as the partition coefficient log Kow using the traditional shake-flask method. The in vitro inhibitory activity on acetylcholinesterase from electric eel and butyrylcholinesterase isolated from equine serum was determined. The inhibitory activity on acetylcholinesterase was significantly higher than that of the standard drug rivastigmine. The discussed compounds are also promising inhibitors of butyrylcholinesterase, as some of the prepared compounds inhibit butyrylcholinesterase better than the internal standards rivastigmine and galanthamine. The highest inhibitory activity (IC50 = 1.66 μmol/L) corresponds to the compound 1-(4-isopropylphenyl)-3-[(R)-1-(6-fluorobenzo[d]thiazol-2-yl)ethyl]imidazolidine-2,4,5-trione (3d). For all the studied compounds, the relationships between the lipophilicity and the chemical structure as well as their structure-activity relationships are discussed.
A Molecular Antenna Coordination Polymer from Cadmium(II) and 4,4’-Bipyridine Featuring Three Distinct Polymer Strands in the Crystal
Authors: Seidel Rüdiger W. , Goddard Richard , Zibrowius Bodo , Oppel Iris M.
Published: September 2011

Reaction of cadmium perchlorate and the prototypical linear bridging ligand 4,4’-bipyridine (4,4’-bipy) in an ethanol/water mixture affords the one-dimensional coordination polymer, [{Cd(m-4,4’-bipy)(4,4’-bipy)2(H2O)2}(ClO4)2 × 2 4,4’-bipy × 4.5 H2O]n (1). The Cd2+ ions adopt an octahedral coordination sphere and are joined into linear chains by 4,4’-bipy via two trans coordination sites. The remaining two trans sites in the equatorial plane carry terminally monodentate-bound 4,4’-bipy ligands, resulting in a molecular antenna arrangement. The two axial sites of each Cd2+ ion are occupied by aqua ligands. Compound 1 crystallizes in the non-centrosymmetric, monoclinic space group C2 with three similar, crystallographically independent, cationic coordination polymer strands in the unit cell, which essentially differ only in the conformations of the 4,4’-bipyridyl ligands. Consistent with the similarity of the local coordination environments of the three independent Cd atoms in the structure, 113Cd MAS NMR spectroscopy reveals a single resonance line at 89 ppm.
Conductometric Sensors for Monitoring Degradation of Automotive Engine Oil
Authors: Latif Usman , Dickert Franz L.
Published: September 2011

Conductometric sensors have been fabricated by applying imprinted polymers as receptors for monitoring engine oil quality. Titania and silica layers are synthesized via the sol-gel technique and used as recognition materials for acidic components present in used lubricating oil. Thin-film gold electrodes forming an interdigitated structure are used as transducers to measure the conductance of polymer coatings. Optimization of layer composition is carried out by varying the precursors, e.g., dimethylaminopropyltrimethoxysilane (DMAPTMS), and aminopropyl-triethoxysilane (APTES). Characterization of these sensitive materials is performed by testing against oil oxidation products, e.g., carbonic acids. The results depict that imprinted aminopropyltriethoxysilane (APTES) polymer is a promising candidate for detecting the age of used lubricating oil. In the next strategy, polyurethane-nanotubes composite as sensitive material is synthesized, producing appreciable differentiation pattern between fresh and used oils at elevated temperature with enhanced sensitivity.
Artificial Skin Ridges Enhance Local Tactile Shape Discrimination
Authors: Salehi Saba , Cabibihan John-John , Ge Shuzhi Sam
Published: September 2011

One of the fundamental requirements for an artificial hand to successfully grasp and manipulate an object is to be able to distinguish different objects’ shapes and, more specifically, the objects’ surface curvatures. In this study, we investigate the possibility of enhancing the curvature detection of embedded tactile sensors by proposing a ridged fingertip structure, simulating human fingerprints. In addition, a curvature detection approach based on machine learning methods is proposed to provide the embedded sensors with the ability to discriminate the surface curvature of different objects. For this purpose, a set of experiments were carried out to collect tactile signals from a 2 × 2 tactile sensor array, then the signals were processed and used for learning algorithms. To achieve the best possible performance for our machine learning approach, three different learning algorithms of Naïve Bayes (NB), Artificial Neural Networks (ANN), and Support Vector Machines (SVM) were implemented and compared for various parameters. Finally, the most accurate method was selected to evaluate the proposed skin structure in recognition of three different curvatures. The results showed an accuracy rate of 97.5% in surface curvature discrimination.
Ethanol Vapor Sensing Properties of Triangular Silver Nanostructures Based on Localized Surface Plasmon Resonance
Authors: Ma Wenying , Yang Huan , Wang Weimin , Gao Ping , Yao Jun
Published: September 2011

A sensitive volatile organic vapor sensor based on the LSPR properties of silver triangular nanoprisms is proposed in this paper. The triangular nanoprisms were fabricated by a nanosphere lithography (NSL) method. They have sharp vertices and edges, and are arranged in an ideal hexangular array. These characteristics ensure that they exhibit an excellent LSPR spectrum and a high sensitivity to the exterior environment changes. The LSPR spectra responding to ethanol vapor and four other volatile organic vapors—acetone, benzene, hexane and propanol—were measured with a UV-vis spectrometer in real time. Compared with the other four vapors, ethanol exhibits the highest sensitivity (~0.1 nm/mg L−1) and the lowest detection limit (~10 mg/L) in the spectral tests. The ethanol vapor test process is also fast (~4 s) and reversible. These insights demonstrate that the triangular nanoprism based nano-sensor can be used in ethanol vapor detection applications.
Unconventional Use of LC3 by Coronaviruses through the Alleged Subversion of the ERAD Tuning Pathway
Authors: Reggiori Fulvio , De Haan Cornelis A.M. , Molinari Maurizio
Published: September 2011

Pathogens of bacterial and viral origin hijack pathways operating in eukaryotic cells in many ways in order to gain access into the host, to establish themselves and to eventually produce their progeny. The detailed molecular characterization of the subversion mechanisms devised by pathogens to infect host cells is crucial to generate targets for therapeutic intervention. Here we review recent data indicating that coronaviruses probably co-opt membranous carriers derived from the endoplasmic reticulum, which contain proteins that regulate disposal of misfolded polypeptides, for their replication. In addition, we also present models describing potential mechanisms that coronaviruses could employ for this hijacking.
Restricted Access to Myeloid Cells Explained
Authors: Planelles Vicente
Published: September 2011

The lentiviral accessory protein, Vpx, is known to counteract a restriction factor that is specific to myeloid cells, such as macrophages and dendritic cells. This review summarizes the findings in two seminal studies that identify SAMHD1 as the cellular protein that is responsible for myeloid cell restriction, and establish the existence of other types of restriction in these cells.
Self-organizing bioinspired oligothiophene–oligopeptide hybrids
Authors: Shaytan Alexey K , Schillinger Eva-Kathrin , Mena-Osteritz Elena , Schmid Sylvia , Khalatur Pavel G , Bäuerle Peter , Khokhlov Alexei R
Published: September 2011

In this minireview, we survey recent advances in the synthesis, characterization, and modeling of new oligothiophene–oligopeptide hybrids capable of forming nanostructured fibrillar aggregates in solution and on solid substrates. Compounds of this class are promising for applications because their self-assembly and stimuli-responsive properties, provided by the peptide moieties combined with the semiconducting properties of the thiophene blocks, can result in novel opportunities for the design of advanced smart materials. These bio-inspired molecular hybrids are experimentally shown to form stable fibrils as visualized by AFM and TEM. While the experimental evidence alone is not sufficient to reveal the exact molecular organization of the fibrils, theoretical approaches based on quantum chemistry calculations and large-scale atomistic molecular dynamics simulations are attempted in an effort to reveal the structure of the fibrils at the nanoscale. Based on the combined theoretical and experimental analysis, the most likely models of fibril formation and aggregation are suggested.
Effects of the Demethylating Agent, 5-Azacytidine, on Expression of the Kallikrein-Kinin Genes in Carcinoma Cells of the Lung and Pleura
Authors: Wong Joshua , Sia Yee Yen , Misso Neil L. , Aggarwal Shashi , Ng Angeline , Bhoola Kanti D.
Published: September 2011

Tissue kallikrein (KLK1) and plasma kallikrein (KLKB1) may regulate the growth and proliferation of tumours of the lung and pleura, through the generation of kinin peptides that signal through the kinin B1(BDKRB1) and B2(BDKRB2) receptors. The development and progression of cancer results from genetic mutations, as well as epigenetic changes that include methylation of DNA at CpG islands. The aim of this study was to assess whether expression of the kallikrein-kinin genes in lung cancer and mesothelioma cells is regulated by DNA methylation. Quantitative reverse transcriptase-PCR and immunocytochemistry showed differences in the basal expression of the kallikrein-kinin genes and proteins in lung carcinoma and mesothelioma cells, compared with non-malignant lung epithelial and mesothelial cells, respectively. Following treatment with the demethylating agent, 5-azacytidine (5-AZA),KLKB1mRNA expression was consistently increased in both lung carcinoma and mesothelioma cells, whereasKLK1,BDKRB1andBDKRB2mRNA expression was decreased or unchanged. Increased expression ofKLKB1after 5-AZA treatment suggests it may function as a tumour suppressor gene in cancers of the lung and pleura. Studies on DNA methylation of the kallikrein-kinin genes will enhance understanding of their role in carcinogenesis and provide insights into the importance of kallikreins as tumour biomarkers.
Protein Kinases and Phosphatases in the Control of Cell Fate
Authors: Bononi Angela , Agnoletto Chiara , De Marchi Elena , Marchi Saverio , Patergnani Simone , Bonora Massimo , Giorgi Carlotta , Missiroli Sonia , Poletti Federica , Rimessi Alessandro , Pinton Paolo
Published: September 2011

Protein phosphorylation controls many aspects of cell fate and is often deregulated in pathological conditions. Several recent findings have provided an intriguing insight into the spatial regulation of protein phosphorylation across different subcellular compartments and how this can be finely orchestrated by specific kinases and phosphatases. In this review, the focus will be placed on (i) the phosphoinositide 3-kinase (PI3K) pathway, specifically on the kinases Akt and mTOR and on the phosphatases PP2a and PTEN, and on (ii) the PKC family of serine/threonine kinases. We will look at general aspects of cell physiology controlled by these kinases and phosphatases, highlighting the signalling pathways that drive cell division, proliferation, and apoptosis.
Prophylactic and Therapeutic Breast Conservation inBRCA1/2Mutation Carriers
Authors: Croshaw Randal L. , Marshall Megan L. , Williams Tesha L. , Erb Kathleen M. , Julian Thomas B.
Published: September 2011

Breast-conserving therapy (BCT) for sporadic breast cancer has been widely accepted by surgeons and patients alike. While BCT is associated with a higher risk of ipsilateral breast tumor recurrence (IBTR), it has not been shown to decrease overall survival (OS) in comparison with mastectomy. Many women with aBRCA1/2mutation opt for mastectomy instead of breast-conserving measures at the time of a breast cancer diagnosis. In some cases, this is due to fear of aggressive disease, but to date, there have been no studies offering strong evidence that breast conservation should not be offered to these women.BRCA1/2-associated breast cancer has not been found to be more aggressive or resistant to treatment than comparable sporadic tumors, and no study has shown an actual survival advantage for mastectomy in appropriately treated affected mutation carriers. This paper reviews the available literature for breast conservation and surgical decision making inBRCA1/2mutation carriers.
From Banking to International Governance: Fostering Innovation in Stem Cell Research
Authors: Isasi Rosario , Knoppers Bartha M.
Published: September 2011

Stem cell banks are increasingly recognized as an essential resource of biological materials for both basic and translational stem cell research. By providing transnational access to quality controlled and ethically sourced stem cell lines, stem cell banks seek to foster international collaboration and innovation. However, given that national stem cell banks operate under different policy, regulatory and commercial frameworks, the transnational sharing of stem cell materials and data can be complicating. This paper will provide an overview of the most pressing challenges regarding the governance of stem cell banks, and the difficulties in designing regulatory and commercial frameworks that foster stem cell research. Moreover, the paper will shed light on the numerous international initiatives that have arisen to help harmonize and standardize stem cell banking and research processes to overcome such challenges.
Effect of Feed Restriction during Pregnancy on Performance and Productivity of New Zealand White Rabbit Does
Authors: Nafeaa Abeer , Ahmed Souad Abd Elfattah , Fat Hallah Said
Published: September 2011

This study aimed to evaluate effect of stage of feed restriction on performance and productivity of pregnant does. New Zealand white female rabbits were randomly divided into three groups. Control group was provided daily with 185 g of food increased to 200 g from the 15th day of gestation. was offered daily a restricted amount of food (60% restriction, 111 g) for the first half of pregnancy and then offered 200 g of food daily till parturition. was provided with 185 g of food daily through the first half of pregnancy and then offered daily a restricted amount of food (60% restriction, 120 g) for the second half. After parturition, food was providedadlibitum. Maternal body weights, litter size, litter weight, and average body weight of kits at kindling of showed no change, whereas showed significant reduction in the weights of does at the 4th week of pregnancy and at kindling. The birth weight and weaning weight of were significantly reduced. The highest mortality was recorded in kits of . No significant differences in blood parameters or serum prolactin were observed. The serum protein was significantly reduced .
Thyroid Carcinoma in Children and Adolescents—Systematic Review of the Literature
Authors: Vaisman Fernanda , Corbo Rossana , Vaisman Mario
Published: September 2011

Thyroid cancer in children and adolescents is usually a major concern for physicians, patients, and parents. Controversies regarding the aggressiveness of the clinical presentation and the ideal therapeutic approach remain among the scientific community. The current recommendations and staging systems are based on data generated by studies in adults, and this might lead to overtreating in some cases as well as undertreating in others. Understanding the differences in the biology, clinical course, and outcomes in this population is crucial for therapeutic decisions. This paper evaluates the biology, clinical presentation, recurrences, and overall survival as well as the staging systems in children and adolescents with differentiated thyroid cancer.
Antibacterial Activities of Actinomycete Isolates Collected from Soils of Rajshahi, Bangladesh
Authors: Rahman Md. Ajijur , Islam Mohammad Zahidul , Islam Md. Anwar Ul
Published: September 2011

This study was performed to isolate actinomycete colonies having antibacterial activity from soil samples collected from different places around Rajshahi, Bangladesh. Thirty actinomycete colonies were isolated in pure culture from five soil samples using Starch-casein-nitrate-agar medium. The isolates were grouped in five color series based on their aerial mycelia color and screened for their antibacterial activity against a range of test bacteria. Sixteen isolates (53.3%) were found to have moderate to high activity against four gram-positive and four gram-negative bacteria. Since many isolates showed inhibitory activity against indicator bacteria, it is suggestive that Bangladeshi soil could be an interesting source to explore for antibacterial secondary metabolites.
Digestive Alkaline Proteases from Zosterisessor ophiocephalus, Raja clavata, and Scorpaena scrofa: Characteristics and Application in Chitin Extraction
Authors: Nasri Rim , Younes Islem , Lassoued Imen , Ghorbel Sofiane , Ghorbel-Bellaaj Olfa , Nasri Moncef
Published: September 2011

The aim of this work was to study some biochemical characteristics of crude alkaline protease extracts from the viscera of goby (Zosterisessor ophiocephalus), thornback ray (Raja clavata), and scorpionfish (Scorpaena scrofa), and to investigate their applications in the deproteinization of shrimp wastes. At least four caseinolytic proteases bands were observed in zymogram of each enzyme preparation. The optimum pH for enzymatic extracts activities of Z. ophiocephalus, R. clavata, and S. scrofa were 8.0-9.0, 8.0, and 10.0, respectively. Interestingly, all the enzyme preparations were highly stable over a wide range of pH from 6.0 to 11.0. The optimum temperatures for enzyme activity were 50∘C for Z. ophiocephalus and R. clavata and 55∘C for S. scrofa crude alkaline proteases. Proteolytic enzymes showed high stability towards non-ionic surfactants (5% Tween 20, Tween 80, and Triton X-100). In addition, crude proteases of S. scrofa, R. clavata, and Z. ophiocephalus were found to be highly stable towards oxidizing agents, retaining 100%, 70%, and 66%, respectively, of their initial activity after incubation for 1 h in the presence of 1% sodium perborate. They were, however, highly affected by the anionic surfactant SDS. The crude alkaline proteases were tested for the deproteinization of shrimp waste in the preparation of chitin. All proteases were found to be effective in the deproteinization of shrimp waste. The protein removals after 3 h of hydrolysis at 45∘C with an enzyme/substrate ratio (E/S) of 10 were about 76%, 76%, and 80%, for Z. ophiocephalus, R. clavata, and S. scrofa crude proteases, respectively. These results suggest that enzymatic deproteinization of shrimp wastes by fish endogenous alkaline proteases could be applicable to the chitin production process.
Gene Duplication and the Genome Distribution of Sex-Biased Genes
Authors: Gallach Miguel , Domingues Susana , Betrán Esther
Published: September 2011

In species that have two sexes, a single genome encodes two morphs, as each sex can be thought of as a distinct morph. This means that the same set of genes are differentially expressed in the different sexes. Many questions emanate from this statement. What proportion of genes contributes to sexual dimorphism? How do they contribute to sexual dimorphism? How is sex-biased expression achieved? Which sex and what tissues contribute the most to sex-biased expression? Do sex-biased genes have the same evolutionary patterns as nonbiased genes? We review the current data on sex-biased expression in species with heteromorphic sex chromosomes and comment on the most important hypotheses suggested to explain the origin, evolution, and distribution patterns of sex-biased genes. In this perspective we emphasize how gene duplication serves as an important molecular mechanism to resolve genomic clashes and genetic conflicts by generating sex-biased genes, often sex-specific genes, and contributes greatly to the underlying genetic basis of sexual dimorphism.
Nigerian health workers’ views concerning factors influencing paediatric adherence to anti-retroviral therapy
Authors: Ehlers Valerie J. , Chiegil Robert J.
Published: September 2011

Few studies have focused on paediatric anti-retroviral therapy (ART) adherence in Nigeria, probably because of the ethical challenges involved in studying children. The study aimed to identify factors that influence paediatric ART adherence as perceived by health care workers providing ART services in two cities in Nigeria. Knowledge about such factors would be used to formulate recommendations for enhancing paediatric ART adherence in Nigeria, for facilitating the tasks of the health care workers and for enhancing the ART programme’s effectiveness. An exploratory descriptive qualitative research design was used to identify and to describe health care workers’ views in Kano and Lagos, Nigeria. Three focus group discussions were conducted at two clinics that provide free paediatric ARVs (antiretroviral drugs). The transcribed data were analysed by using the framework approach of data analysis. Health care providers perceived poverty, illiteracy, stigma, discrimination, inappropriate care approaches, and parental dynamics as factors that influence paediatric ART adherence. Paediatric ART adherence levels in Nigeria could be enhanced by emphasising paediatric ART adherence counselling and by adopting a comprehensive family centred care approach, by improving free paediatric ART services and by empowering parents and reducing stigma and discrimination.OpsommingMin studies het al op pediatriese anti-retrovirale behandeling (ARB) nakoming in Nigerië gefokus, wat moontlik toegeskryf kan word aan die etiese uitdagings betrokke by die bestudering van kinders. Die studie het gepoog om faktore te identifiseer wat pediatriese ARB nakoming kan beΪnvloed, soos waargeneem deur gesondheidsdienswerkers wat ARB dienste verskaf in twee stede in Nigerië. Kennis van sulke faktore sal aangewend word om aanbevelings te maak om die pediatriese ARB nakoming in Nigerië te verbeter, om die taak van die gesondheidsorgwerkers te vergemaklik en om die ARM (anti-retrovirale medisyne) program se doeltreffendheid te verbeter.‘n Verkennende beskrywende kwalitatiewe navorsingsontwerp was benut ten einde gesondheidswerkers in Kano en Lagos, Nigerië, se standpunte te identifiseer en te beskryf. Drie fokusgroepbesprekings is gehou in twee klinieke wat gratis ARMs verskaf. Die getranskribeerde data is ontleed deur die raamwerkbenadering tot data analise te gebruik. Gesondheidsdienswerkers het waargeneem dat armoede en ongeletterdheid, stigma en diskriminasie, ontoepaslike sorgbenaderings en ouerlike dinamika, faktore was wat pediatriese ARB nakoming beĭnvloed het. Pediatriese ARB nakomingsvlakke in Nigerië kan verbeter word deur pediatriese ARB nakomingsberading te beklemtoon, deur die aanvaarding van ‘n omvattende gesinsgesentreerde sorgbenadering wat gratis ARB dienste bied, deur die verbetering van ARB dienste, die bemagtiging van ouers en die vermindering van stigma en diskriminasie.
Challenges of Executive Information Systems in listed Johannesburg Stock Exchange companies
Authors: Papageorgiou Elmarie , De Bruyn Herman
Published: September 2011

Background: The widespread use of Executive Information Systems (EISs) as a management information tool was noted in listed Johannesburg Stock Exchange (JSE) companies. The digital business environment exposed executives to so much data that data need to be converted into useful information that is organised and summarised.Objectives: The purpose of this study is to establish and to determine the existence, and to what extent EISs exist in all levels of management and to identify the challenges companies experienced in listed JSE companies. Therefore the problem exists that EIS-users at all levels of management are unaware of the challenges of EISs and that EISs can be used as a tool to analyse their businesses’ performance and competitiveness.Method: A mixed method was used; both quantitative and qualitative in nature. Questionnaires were sent to 334 listed JSE companies and 13 interviews were conducted with users of EISs in all levels of management.Results: The results of the study demonstrate that the majority of respondents of the questionnaire have an EIS or plan to implement an EIS. The results further revealed the respondents’ positive attitude towards EISs as it is an excellent management information tool that adds strategic value to their business, that is critical for real-time decision-making, solves problems and creates a competitive edge. From the results it is evident that there is a need for an EIS to be ‘everybody’s information system’. The results of the interviews demonstrate that an EIS is a seamless reliable system necessary for proper timeous decision-making. The respondents to the questionnaire and the interviewees indicated that they understood the value of EISs as a useful part of their company.Conclusion: The study adds value to the awareness and understanding of EISs that creates a business environment in which business and management can enhance sustainability and strategic competitiveness.
Patient perspectives in the Management of Post-Herpetic Neuralgia
Authors: Harkness T. LaNeigh , Merritt Pearl
Published: September 2011

In today's healthcare environment prevention plays a pivotal role. With the aging population, herpes zoster (HZ) pain and post-herpetic neuralgia (PHN) are two conditions that will have a significant impact on the healthcare industry. The common held belief that HZ patients are protected from recurrence, after one episode of shingles no longer holds true. In a recent study data has shown recurrence rates of over five percent. The evidence suggests those who experienced pain lasting more than 30 days after the initial onset of shingles were more likely to have a recurrence, especially in the first three to four years after the initial episode. 6 Understanding the variables that influence the patient s perspective of pain can impact healthcare delivery. Increasing the quality of life for the elderly through preventive measures including education, immunization, and implementation of early treatment guidelines can significantly reduce the incidence of PHN.
Introduction of New Laryngeal Closure Methods for Patients with Intractable Aspiration
Authors: Tateda Masaru , Yokoyama Tetsuya , Mizukawa Atsuhiro , Sato Hiroaki
Published: September 2011

The aging population in Japan has recently resulted in a rapid increase in elderly individuals. Airway management is thus being required more and more often. Aspiration pneumonia is a life-threatening problem among patients with swallowing problems. Several new surgical methods of laryngeal closure that are easier and safer than previous methods have been developed. Among these new methods, we have performed the Kano method as closure of the larynx using double flaps of the divided craniad vocal folds and the divided caudad vocal folds with partial resection of the thyroid and cricoid cartilages for patients with intractable aspiration. We encountered minor leakage in two patients, but these soon closed spontaneously. This procedure is less invasive than other methods such as total laryngectomy and tracheal separation and has great advantages in terms of low blood loss and short duration of the operation.
Combinatorics
Authors: Kahn Jeff , Steger Angelika , Sudakov Benjamin
Published: September 2011

Combinatorics is a fundamental mathematical discipline which focuses on the study of discrete objects and their properties. The current workshop brought together researchers from diverse fields such as Extremal and Probabilistic Combinatorics, Discrete Geometry, Graph theory, Combiantorial Optimization and Algebraic Combinatorics for a fruitful interaction. New results, methods and developments and future challenges were discussed. This is a report on the meeting containing abstracts of the presentations and a summary of the problem session.
Set Theory
Authors: Friedman Sy-David , Magidor Menachem , Woodin W. Hugh
Published: September 2011

This stimulating workshop exposed some of the most exciting recent develops in set theory, including major new results about the proper forcing axiom, stationary reflection, gaps in
P
(ω)/Fin, iterated forcing, the tree property, ideals and colouring numbers, as well as important new applications of set theory to
C
*-algebras, Ramsey theory, measure theory, representation theory, group theory and Banach spaces.