bluuebunny/crossref_metadata_2025_split huggingface dataset:
A model to control the epidemic of H5N1 influenza at the source
Authors: Guan Y , Chen H , Li KS , Riley S , Leung GM , Webster R , Peiris JSM , Yuen KY 
Published: November 2007

AbstractBackgroundNo country is fully prepared for a 1918-like pandemic influenza. Averting a pandemic of H5N1 influenza virus depends on the successful control of its endemicity, outbreaks in poultry and occasional spillage into human which carries a case-fatality rate of over 50%. The use of perimetric depopulation and vaccination has failed to halt the spread of the epidemic. Blanket vaccination for all poultry over a large geographical area is difficult. A combination of moratorium, segregation of water fowls from chickens and vaccination have been proved to be effective in the Hong Kong Special Administrative Region (HKSAR) since 2002 despite endemicity and outbreaks in neighbouring regions. Systematic surveillance in southern China showed that ducks and geese are the primary reservoirs which transmit the virus to chickens, minor poultry and even migratory birds.Presentation of the hypothesisWe hypothesize that this combination of moratorium, poultry segregation and targeted vaccination if successfully adapted to an affected district or province in any geographical region with high endemicity would set an example for the control in other regions.Testing the hypothesisA planned one-off moratorium of 3 weeks at the hottest month of the year should decrease the environmental burden as a source of re-infection. Backyard farms will then be re-populated by hatchlings from virus-free chickens and minor poultry only. Targeted immunization of the ducks and geese present only in the industrial farms and also the chickens would be strictly implemented as blanket immunization of all backyard poultry is almost impossible. Freely grazing ducks and geese would not be allowed until neutralizing antibodies of H5 subtype virus is achieved. As a proof of concept, a simple mathematical model with susceptible-infected-recovered (SIR) structure of coupled epidemics between aquatic birds (mainly ducks and geese) and chickens was used to estimate transmissibility within and between these two poultry populations. In the field the hypothesis is tested by prospective surveillance of poultry and immunocompetent patients hospitalized for severe pneumonia for the virus before and after the institution of these measures.Implications of the HypothesisA combination of targeted immunization with the correct vaccine, segregation of poultry species and moratorium of poultry in addition to the present surveillance, biosecurity and hygienic measures at the farm, market and personal levels could be important in the successful control of the H5N1 virus in poultry and human for an extensive geographical region with continuing outbreaks. Alternatively a lesser scale of intervention at the district level can be considered if there is virus detection without evidence of excess poultry deaths since asymptomatic shedding is common in waterfowls.
BMP-6 promotes E-cadherin expression through repressing δEF1 in breast cancer cells
Authors: Yang Shuang , Du Jun , Wang Zhaoqi , Yuan Wei , Qiao Yuhuan , Zhang Ming , Zhang Jie , Gao Songyuan , Yin Jian , Sun Baocun , Zhu Tianhui 
Published: November 2007

Abstract

Background
Bone morphogenetic protein-6 (BMP-6) is critically involved in many developmental processes. Recent studies indicate that BMP-6 is closely related to tumor differentiation and metastasis.

Methods
Quantitative RT-PCR was used to determine the expression of BMP-6, E-cadherin, and δEF1 at the mRNA level in MCF-7 and MDA-MB-231 breast cancer cells, as well as in 16 breast cancer specimens. Immunoblot analysis was used to measure the expression of δEF1 at the protein level in δEF1-overexpressing and δEF1-interfered MDA-MB-231 cells. Luciferase assay was used to determine the rhBMP-6 or δEF1 driven transcriptional activity of the E-cadherin promoter in MDA-MB-231 cells. Quantitative CHIP assay was used to detect the direct association of δEF1 with the E-cadherin proximal promoter in MDA-MB-231 cells.

Results
MCF-7 breast cancer cells, an ER+ cell line that expressed high levels of BMP-6 and E-cadherin exhibited very low levels of δEF1 transcript. In contrast, MDA-MB-231 cells, an ER- cell line had significantly reduced BMP-6 and E-cadherin mRNA levels, suggesting an inverse correlation between BMP-6/E-cadherin and δEF1. To determine if the same relationship exists in human tumors, we examined tissue samples of breast cancer from human subjects. In 16 breast cancer specimens, the inverse correlation between BMP-6/E-cadherin and δEF1 was observed in both ER+ cases (4 of 8 cases) and ER- cases (7 of 8 cases). Further, we found that BMP-6 inhibited δEF1 transcription, resulting in an up-regulation of E-cadherin mRNA expression. This is consistent with our analysis of the E-cadherin promoter demonstrating that BMP-6 was a potent transcriptional activator. Interestingly, ectopic expression of δEF1 was able to block BMP-6-induced transactivation of E-cadherin, whereas RNA interference-mediated down-regulation of endogenous δEF1 in breast cancer cells abolished E-cadherin transactivation by BMP-6. In addition to down-regulating the expression of δEF1, BMP-6 also physically dislodged δEF1 from E-cadherin promoter to allow the activation of E-cadherin transcription.

Conclusion
We conclude that repression of δEF1 plays a key role in mediating BMP-6-induced transcriptional activation of E-cadherin in breast cancer cells. Consistent with the fact that higher level of δEF1 expression is associated with more invasive phenotype of breast cancer cells, our collective data suggests that δEF1 is likely the switch through which BMP-6 restores E-cadherin-mediated cell-to-cell adhesion and prevents breast cancer metastasis.
Simultaneous Aurora-A/STK15 overexpression and centrosome amplification induce chromosomal instability in tumour cells with a MIN phenotype
Authors: Lentini Laura , Amato Angela , Schillaci Tiziana , Di Leonardo Aldo 
Published: November 2007

Abstract

Background
Genetic instability is a hallmark of tumours and preneoplastic lesions. The predominant form of genome instability in human cancer is chromosome instability (CIN). CIN is characterized by chromosomal aberrations, gains or losses of whole chromosomes (aneuploidy), and it is often associated with centrosome amplification. Centrosomes control cell division by forming a bipolar mitotic spindle and play an essential role in the maintenance of chromosomal stability.
However, whether centrosome amplification could directly cause aneuploidy is not fully established. Also, alterations in genes required for mitotic progression could be involved in CIN.
A major candidate is represented by Aurora-A/STK15 that associates with centrosomes and is overexpressed in several types of human tumour.

Methods
Centrosome amplification were induced by hydroxyurea treatment and visualized by immunofluorescence microscopy. Aurora-A/STK15 ectopic expression was achieved by retroviral infection and puromycin selection in HCT116 tumour cells. Effects of Aurora-A/STK15 depletion on centrosome status and ploidy were determined by Aurora-A/STK15 transcriptional silencing by RNA interference. Changes in the expression levels of some mitotic genes were determined by Real time RT-PCR.

Results
We investigated whether amplification of centrosomes and overexpression of Aurora-A/STK15 induce CIN using as a model system a colon carcinoma cell line (HCT116). We found that in HCT116 cells, chromosomally stable and near diploid cells harbouring a MIN phenotype, centrosome amplification induced by hydroxyurea treatment is neither maintained nor induces aneuploidy. On the contrary, ectopic overexpression of Aurora-A/STK15 induced supernumerary centrosomes and aneuploidy. Aurora-A/STK15 transcriptional silencing by RNA interference in cells ectopically overexpressing this kinase promptly decreased cell numbers with supernumerary centrosomes and aneuploidy.

Conclusion
Our results show that centrosome amplification alone is not sufficient to induce chromosomal instability in colon cancer cells with a MIN phenotype. Alternatively, centrosome amplification has to be associated with alterations in genes regulating mitosis progression such as Aurora-A/STK15 to trigger CIN.
Inflammation: a way to understanding the evolution of portal hypertension
Authors: Aller María-Angeles , Arias Jorge-Luis , Cruz Arturo , Arias Jaime 
Published: November 2007

Abstract

Background
Portal hypertension is a clinical syndrome that manifests as ascites, portosystemic encephalopathy and variceal hemorrhage, and these alterations often lead to death.

Hypothesis
Splanchnic and/or systemic responses to portal hypertension could have pathophysiological mechanisms similar to those involved in the post-traumatic inflammatory response.
The splanchnic and systemic impairments produced throughout the evolution of experimental prehepatic portal hypertension could be considered to have an inflammatory origin. In portal vein ligated rats, portal hypertensive enteropathy, hepatic steatosis and portal hypertensive encephalopathy show phenotypes during their development that can be considered inflammatory, such as: ischemia-reperfusion (vasodilatory response), infiltration by inflammatory cells (mast cells) and bacteria (intestinal translocation of endotoxins and bacteria) and lastly, angiogenesis. Similar inflammatory phenotypes, worsened by chronic liver disease (with anti-oxidant and anti-enzymatic ability reduction) characterize the evolution of portal hypertension and its complications (hepatorenal syndrome, ascites and esophageal variceal hemorrhage) in humans.

Conclusion
Low-grade inflammation, related to prehepatic portal hypertension, switches to high-grade inflammation with the development of severe and life-threatening complications when associated with chronic liver disease.
Blood parameters in growing pigs fed increasing levels of bacterial protein meal
Authors: Hellwing Anne Louise F , Tauson Anne-Helene , Skrede Anders 
Published: November 2007

Abstract
The experiment investigated the effects of increasing dietary levels of bacterial protein meal (BPM) on various blood parameters reflecting protein and fat metabolism, liver function, and purine base metabolism in growing pigs. Sixteen barrows were allocated to four different experimental diets. The control diet was based on soybean meal. In the other three diets soybean meal was replaced with increasing levels of BPM, approximately 17%, 35%, and 50% of the nitrogen being derived from BPM. Blood samples from the jugular vein were taken when the body weights of the pigs were approximately 10 kg, 21 kg, 45 kg, and 77 kg. The blood parameters reflecting fat metabolism and liver function were not affected by diet. Both the plasma albumin and uric acid concentrations tended to decrease (P = 0.07 and 0.01, respectively) with increasing dietary BPM content, whereas the plasma glucose concentration tended to increase (P = 0.07) with increasing dietary BPM content. It was concluded that up to 50% of the nitrogen could be derived from BPM without affecting metabolic function, as reflected in the measured blood parameters.
Prevalence and Predictors of Complementary Therapy Use in Advanced-Stage Breast Cancer Patients
Authors: Gross Abigail M. , Liu Qin , Bauer-Wu Susan 
Published: November 2007

Purpose Information on the use of complementary therapies in patients with advanced-stage cancer is limited. Given the disease and treatment complexities associated with the care of patients with metastatic cancer, oncology clinicians would benefit from having an appreciation of the extent of usage of unconventional, adjunctive therapies among these patients. This study evaluated the prevalence and demographic predictors of complementary therapy use in a sample of women with metastatic breast cancer. Methods Subjects with stage IV breast cancer were recruited from six treatment facilities in New England. A written, mailed survey assessing complementary therapy use and sociodemographic information was completed by each subject, while disease and treatment information was obtained from medical records. Descriptive statistics and multivariate logistic regression analyses were conducted. Results Of the 173 participants, 78% used at least one type of complementary therapy, 43% used two or more types, and 23% used three or more types, excluding spiritual practices and physical exercise. When including spiritual practices and physical exercise, 90% used at least one complementary therapy, 70% used two or more types, and 45% used three or more types. Visits to alternative health practitioners were predicted by younger age (P = .009) and higher education level (P = .002). Younger participants (P = .045) were more likely to use and spend more money on vitamins and herbal products (P = .02). Conclusions Use of unconventional therapies is pervasive among metastatic breast cancer patients, particularly among those who are younger and highly educated. Oncology providers need to assess patients' complementary therapy use and consider potential interactions with prescribed treatment protocols.
Supramolecular Biomaterials. A Modular Approach towards Tissue Engineering
Authors: Dankers Patricia Y W , Meijer E W 
Published: November 2007

Abstract
Supramolecular chemistry is an exciting area of science that plays a central role in bringing different disciplines together, ranging from molecular medicine to nanotechnology. Materials science based on supramolecular interactions is an emerging field, which has made important steps forward in the past ten years. The self-assembly of small synthetic molecules into long-chain architectures gives rise to the careful design of supramolecular polymers or fibers based on highly directional, reversible, non-covalent interactions. Much afford is put into the development of supramolecular (polymeric) materials with true materials properties, both in solution and in the solid state. These supramolecular materials are beginning to reach the market in all kind of applications. The field of regenerative medicine in general and that of tissue engineering in particular is one of the most challenging areas in which supramolecular materials might have a high potential. In tissue engineering, the biological environment and the interactions of cells with the artificial biomaterial is of utmost importance for the functioning of the implant, i.e. the engineered tissue. Ideal biomaterials do not only have to fulfil the biomaterials trinity of tuneable mechanical properties, regulation of the degradability and the ease for bioactivity incorporation, but also have to mimic the natural environment where the materials are brought into. Therefore, a modular, self-assembly approach using several supramolecular building blocks is an exquisite way to produce such “responsive” biomaterials. It is proposed that the artificial materials described in this account have the same type of dynamic ability to adapt its biofunctionality as is so well known for the living cells in the host tissue. This account will highlight two systems, i.e. self-assembling oligopeptide fibers as pioneered by Stupp et al. and Zhang et al., and our hydrogen-bonded supramolecular polymers, to show the potential of a modular approach to dynamic biomaterials for tissue engineering.
Conducting-Polymer-Based Chemical Sensors: Transduction Mechanisms
Authors: Sugiyasu Kazunori , Swager Timothy M 
Published: November 2007

Abstract
Conducting organic polymers show great promise as sensory materials. The transport of charge in these systems imparts the ability to attain high sensitivity to analytes of interest. This contribution reviews a number of different mechanisms by which analytes can interact with organic conducting polymers to create changes in their resistivity. New sensor systems based upon triaryl-methyl carbocations are also reported for the first time. The design of specific molecular recognition can impart selectivity in this process and in addition the nature of the conducting polymer can also lead to selectivity for different analytes.
Highly Efficient Method for Constructing a Single-Stranded Comb-Like Oligonucleotide via Reversible Photocrosslinking
Authors: Ogasawara Shinzi , Yoshimura Yoshinaga , Hayashi Masayuki , Saito Isao , Fujimoto Kenzo 
Published: November 2007

Abstract
Branched oligodeoxyribonucleotides (ODNs) are key molecules in constructing nano-scale structures such as DNA lattices, dendrimer-like DNA as well as DNA devices including DNA walkers, DNA memory, and DNA computer. In this paper, two types of highly efficient methods were used to construct the comb-like DNA by using template-directed reversible DNA photocrosslinking via 5-(2-carbamoylvinyl)-2′-deoxyuridine (cvU). The efficiency and thermodynamic stability of three types of reversible DNA photocrosslinked, linear ODN, single-branched ODN (5′-end) and single-branched ODN (mid) reported previously, were also compared. The results show that the most efficient one of the three is a single-branched ODN (5′-end), despite its low thermodynamic stability. In addition, we also showed that this reversible photocrosslinking method is applicable to nanotechnology by constructing comb-like DNA. This method should have great potential in nanotechnology by serving as a platform for fabrication and synthesis, because their sizes and structures can be changed through the alteration of building blocks. We believe that this method is versatile and may find a myriad of applications in the nano-biotechnology field.
Driving Force for a Catalyzed Reaction Derived from a Reaction Rate Spectrum
Authors: Yasuda Yusuke 
Published: November 2007

Abstract
Based on the acceleration of Gibbs free energy, −d2G⁄dt2, a kinetic (or falls) model for a catalyzed CO oxidation was developed. Since GT(t) of the system inevitably decreases during a reaction, it may be regarded as the height of water in the model; −d2GT⁄dt2≡FT corresponding to gravity, may be regarded as the driving force for the reaction to occur. The reaction mechanism for CO(X)+(1/2)O2(Y)→CO2(Z) can be divided into two parallel transformations, X↔AX↔BX→ZX and Y↔AY↔BY→ZY, which are composed of the three elementary steps accompanied by intermediate A and B. The driving force FX for AX and BX to proceed and also FY for AY and BY were determined separately. Because FT (=FX+FY), FX, and FY were independent of t in a definite period, they (instead of G(t)) are useful for describing coupling among the elementary steps and correlations among the intermediates. The reaction can be written X+Y+@→Z∗+@, where Z∗ means that Z leaving catalysts has hyperthermal energy and @ denotes the active site where BY (assigned to subsurface oxygen) is located. The present dissipative structure is supported by FT, not by any autocatalytic reaction.
Matrix-Isolation Infrared Spectroscopic and Density Functional Theory Studies on Reactions of Laser-Ablated Lead and Tin Atoms with Water Molecules
Authors: Teng Yun-Lei , Jiang Ling , Han Song , Xu Qiang 
Published: November 2007

Abstract
Reactions of laser-ablated lead and tin atoms with water molecules in excess argon were studied by infrared spectroscopy. Insertion products HMOH and HMO (M=Pb and Sn) formed in the present experiments and characterized using infrared spectroscopy on the basis of the results of isotopic shifts, mixed isotopic splitting patterns, stepwise annealing, changes in reagent concentration and laser energy, and a comparison with theoretical predictions. Density functional theory calculations were performed on these molecules and the corresponding transition states. Agreement between the experimental and calculated vibrational frequencies, relative absorption intensities, and isotopic shifts supports the identification of these molecules from the matrix infrared spectra. Plausible reaction mechanisms have been proposed to account for the formation of these molecules.
Novel Solid-State 8H+-Heteropolyacid. Synthesis and Molecular Structure of a Free-Acid Form of a Dawson-Type Sandwich Complex, [Ti2{P2W15O54(OH2)2}2]8−
Authors: Murakami Hideyuki , Hayashi Kunihiko , Tsukada Ikuo , Hasegawa Takeshi , Yoshida Shoko , Miyano Rie , Kato Chika Nozaki , Nomiya Kenji 
Published: November 2007

Abstract
The preparation and structural characterization of a novel molecular solid Brønsted acid based on the Dawson-type sandwich polyoxometalate (POM) are described. The free-acid form of POM, i.e., 8H+-heteropolyacid with the formula H8[Ti2{P2W15O54(OH2)2}2]·31H2O (1) (H8[1a]·31H2O), was prepared by using three different methods: In Method 1, a cation-exchange resin column was used to separate precursor K14H2[Ti2(P2W15O56)2]·26H2O (2), and in Methods 2 and 3, a traditional ether-extraction method was applied for the other precursors, i.e., isolated or in situ generated compound of the tetrameric Ti–O–Ti anhydride species of trititanium(IV)-substituted Dawson POM, K25[{P2W15Ti3O57.5(OH)3}4Cl]·55H2O (3). Compound 1 was characterized by using complete elemental analysis, thermogravimetric (TG) and differential thermal analysis (DTA), Fourier transform infrared (FT-IR) spectroscopy, (31P, 183W) nuclear magnetic resonance (NMR) spectroscopy, X-ray crystallography, and potentiometric titration with n-butylamine. The molecular structure of 1a indicated it to be a di-lacunary species of the saturated sandwich complex, [M4(H2O)2(α-P2W15O56)2]n− (M = transition-metal ions). From the pH-varied 31P NMR spectra of 2 in water, the degree of protonation of the oxygen atoms at the lacunary sites significantly affects the 31P NMR chemical shift. A Hammett acidity constant H0 of 1 in CH3CN (−2.72) was estimated to be almost the same as that of the homo-Dawson heteropolyacid H6[P2W18O62]·17H2O (−2.77).
Preparation and Characterization of Two Solid Supramolecular Inclusion Complexes of Guaiacol with β- and γ-Cyclodextrin
Authors: Song Le Xin , Wang Hai Ming , Yang Yan , Xu Peng 
Published: November 2007

Abstract
Solid inclusion complexes of β- and γ-cyclodextrin (CD) with guaiacol (Gua) were prepared and characterized using elemental analysis, matrix-assisted laser desorption ionization-time of flight mass spectrometry, powder X-ray diffraction, infrared spectroscopy, thermogravimetric analysis and nuclear magnetic resonance spectroscopy. Based on the results of elemental analysis and 1H NMR, the host–guest stoichiometry of the two solid complexes was determined to be one-to-one. X-ray diffraction patterns of the inclusion complexes gave peak locations consistent with intermolecular complexations between CDs and Gua as well as shape and diffraction intensity of these peaks. The solubility of γ-CD was much less than that of α-CD in water through the complex formation of CD with Gua. Upon inclusion the thermal decomposition point of β-CD or γ-CD as host only slightly increased. However, the thermal stability of the complexed Gua was obviously higher in Gua–β-CD than in Gua–γ-CD. The inclusion phenomenon was attributed to the different strength of intermolecular interactions between host and guest. According to 1H NMR titration measurements, binding constants between Gua and CDs were determined. Furthermore, 1H NMR results indicated that the complexed Gua was likely to have stayed in the wider rim of the cavity of β- or γ-CD. PM3 calculations clearly showed that Gua–γ-CD had the most negative interaction energy, whereas Gua was near the secondary hydroxy rim of the cavity of γ-CD.
Isomer Specific Solvent Effect on Photoisomerization of Photoresponsive Polyphenylene Dendrimers with a Stilbene Core
Authors: Okamoto Tomoko , Momotake Atsuya , Shinohara Yoshihiro , Nagahata Ritsuko , Arai Tatsuo 
Published: November 2007

Abstract
The efficiency of cis-to-trans isomerization of stilbene-cored polyphenylene dendrimer with alkyl chain at the pheriphery was one order of magnitude lower in hexane than in benzene, whereas that of trans-to-cis isomerization was slightly higher in hexane than in benzene.