bluuebunny/crossref_metadata_2025 huggingface dataset:
Discrepancy in the near‐solute electric dipole moment calculated from the electric field
Authors: Yang Pei‐Kun
Published: June 2011

The electric dipole momentp(r) was computed as the integral of the permanent dipole moment of the solvent molecule μ(r) weighted by the orientational probability distribution Ω(r;O) over all orientations, whereOis the orientation of the solvent molecule atr. The relationship between Ω(r;O) and the potential of the mean torque was derived;p(r) is proportional to the electric fieldE(r) under the following assumptions: (1) the van der Waals (vdW) interaction is independent of the orientation of the solvent molecule atr; (2) the solvent molecule and its electrical effect are modeled as a point dipole moment; (3) the solvent molecule atris in a region far from the solute; and (4) μE(r) ≪kBT, wherekBis Boltzmann's constant andTis absolute temperature. The errors caused by calculating near‐solute Ω(r) andp(r) fromE(r) are unclear. The results show that Ω(r) is inconsistent with the value calculated fromE(r) for water molecules in the first and second shells of solute with charge stateQ= ±1 e, and a large variation in solvent molecular polarizability γmol(r), which appeared in the first valley of 4πr2E(r) for |Q| < 1 e. Nonetheless,p(r) is consistent with the values calculated fromE(r) for |Q| ≤ 1 e. The implication is that the assumptions for calculatingp(r) can be ignored in the calculation of the solvation free energy of biomolecules, as they pertain to protein folding and protein–protein/ligand interactions. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Molecular dynamics simulation reveals structural and thermodynamic features of kinase activation by cancer mutations within the epidermal growth factor receptor
Authors: Wan Shunzhou , Coveney Peter V.
Published: June 2011

The epidermal growth factor receptor (EGFR) is a major target for drugs in treating lung carcinoma as it promotes cell growth and tumor progression. Structural studies have demonstrated that EGFR exists in an equilibrium between catalytically active and inactive forms, and dramatic conformational transitions occur during its activation. It is known that EGFR mutations promote such conformational changes that affect its activation and drug efficacy. The most common point mutation in lung cancer patients is a leucine to arginine substitution at amino acid 834 (L834R). In a recent article, we have studied changes in drug binding affinities due to cancer mutations of EGFR using ensemble molecular dynamics (MD) simulations. Here, we address an enhanced activation mechanism thought to be associated with this mutation. Using extended timescale MD simulations, the structural and energetic properties are studied for both active and inactive conformations of EGFR. The thermodynamic stabilities of these two conformations are characterized by free energy landscapes estimated from molecular mechanics/Poisson–Boltzmann solvent area calculations. Our study reveals that the L834R mutation introduces conformational changes in both states, adjusting the relative stabilities of active and inactive conformations and hence the activation of the EGFR kinase. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011
Utilization of personal therapy by psychotherapists: a practice‐friendly review and a new study
Authors: Orlinsky David E. , Schofield Margot J. , Schroder Thomas , Kazantzis Nikolaos
Published: June 2011

This article offers both a practice‐friendly review of research on therapists' personal therapy and a new study of personal psychotherapy among 3,995 psychologists, counselors, social workers, psychiatrists, and nurses in 6 English‐speaking countries. The prevalence of personal therapy as it relates to professional discipline, theoretical orientation, gender, and career level are studied. Findings showed that 87% of the overall sample embarked on personal therapy at least once: 94% of analytic/psychodynamic therapists, 91% of humanistic therapists, 73% of cognitive‐behavioral therapists, 82% of the novice therapists to 89% of senior therapists. Both the existing research and this new study demonstrate the extraordinary commonality of personal therapy among psychotherapists, and encourage further use for professional training, clinical practice, and therapist self‐care. © 2011 Wiley Periodicals, Inc. J Clin Psychol: In Session 67:1–15, 2011.
Mixing and solid‐liquid mass transfer characteristics in a three phase pulsed plate column with packed bed of solids in interplate spaces—a novel aerobic immobilized cell bioreactor
Authors: Kodialbail Vidya Shetty , Srinikethan Govindan
Published: June 2011

BACKGROUND: The pulsed plate column (PPC) with packed bed of solids in the interplate spaces finds use as a three phase aerobic bioreactor and is a potential heterogeneous catalytic reactor. Good knowledge of the extent of mixing in the liquid phase and solid‐liquid mass transfer coefficient are essential for modeling, design and optimization of these columns. The present work aims at the study of liquid phase mixing and solid–liquid mass transfer characteristics in a three phase PPC.

RESULTS: Residence time distribution studies were performed. Dispersion number was found to increase with increase in liquid superficial velocities, frequency of pulsation, amplitude of pulsation and the vibrational velocities. Increase in frequency and amplitude of pulsation, and hence increase in vibrational velocity, resulted in increase of the solid–liquid mass transfer coefficient.

CONCLUSIONS: The mixing behaviour in this contactor approximated a mixed flow behaviour. The three phase PPC was found to outperform many other kinds of three phase contactors in terms of solid liquid mass transfer characteristics. Empirical correlations developed can be used for the determination of solid–liquid mass transfer coefficients for three phase PPC and hence can facilitate the design, scale‐up and modeling of these columns, when used as chemical or biochemical reactors. Copyright © 2011 Society of Chemical Industry
Performance of microwave synthesized dual solvent dope solution and lithium bromide additives on poly(ethersulfone) membranes
Authors: Iqbal Ahmed , Ani I. , Rajput Rizwan
Published: June 2011

BACKGROUND: Generally the fabrication of polymeric membranes is a complicated and expensive process since it involves several steps. The preliminary preparation steps involve polymer drying and dissolution and is very time consuming and expensive. Currently, conventional electrothermal heating (CEH) is used to dissolve polyethersulfone in an aprotic solvent for membrane fabrication. Usually CEH requires 6 to 8 h at temperatures of 80 to 95 °C. This paper reports the fabrication and characterization of polyethersulfone (PES) asymmetric ultrafiltration membrane made from microwave (MW) synthesis casting solution consisting of various compositions of double solvents and lithium bromide (LiBr) additive.

RESULTS: Homogeneous dual solvent dope solutions prepared via microware irradiation took only 1 h instead of the 7 h when prepared using CEH. The results also revealed that the membrane permeation and rejection rates, pore size and porosity were dependent on the ratio of LiBr to acetone. Membranes with LiBr kept at 2 and 3 wt% exhibited both high rejection and permeation rates with minimum pore sizes of 1.067 and 1.214 nm respectively. The presence of LiBr and the occurrence of chain scission were elucidated using Fourier transform infrared (FTIR) spectroscopy while its hydrophilic property was confirmed by water absorption and contact angle measurements.

CONCLUSIONS: It was concluded that the microwave technique is capable of producing 1 L membrane solutions in less than 1 h. The membranes prepared from the microwave solutions show good rejection and permeation rates. Copyright © 2011 Society of Chemical Industry
Management scenarios for olive oil mill waste based on characterization and leaching tests
Authors: Coz Alberto , Villegas Mercedes , Andrés Ana , Viguri Javier R. , Mantzavinos Dionissios , Xekoukoulotakis Nikolaos P.
Published: June 2011

BACKGROUND: Olive oil mill waste is a serious environmental problem in the Mediterranean basin given its particular characteristics of high organic content, seasonal and localized generation, and the type of processing involved.

RESULTS: Olive mill waste from a three‐phase mill was characterized by means of total analysis, availability and mobility of the pollutants in order to help the decision‐maker about possible options for its valorization and/or disposal. Water content, loss of ignition, total organic carbon, phenol index and metals concentrations were measured to fully characterize the waste. Three leaching tests (NEN 7341, EN 12457 and UNE CEN‐TS 15364 EX) were carried out to evaluate the environmental hazard of the waste material and the leachates were characterized with respect to electric conductivity, pH, heavy metals, anions and organic pollutants (phenol index and total organic carbon) according to European waste directives. The results were compared with EU regulations for inert, non‐hazardous and hazardous waste disposal.

CONCLUSION: It was found that not only organic parameters must be taken into account concerning the fate of this waste material, but also the mobility of heavy metals and anions should be studied. Furthermore, stabilization/solidification processes are recommended before landfill disposal of this kind of agro‐waste material. Copyright © 2011 Society of Chemical Industry
Production of bioethanol by immobilized Saccharomyces Cerevisiae onto modified sodium alginate gel
Authors: Inal Murat , Yiğitoğlu Mustafa
Published: June 2011

BACKGROUND: Microbial bioethanol production is an important option in view of the finite global oil reserves. Bioethanol fermentation was carried out using immobilized microorganisms (Saccharomyces cerevisiae, Zymomonas mobilis, Pichia stipitis, etc.), which has many advantages compared with the use of free cells. Various support materials have been used for bioethanol fermentation, and alginate gels have been one of the most widely used matrices for cell entrapment. The aim of this study was increased bioethanol production by Saccharomyces cerevisiae immobilized on alginate gels. First, N‐vinyl‐2‐pyrrolidone was grafted onto sodium alginate. Then, the properties of ethanol production were investigated using the matrix obtained.

RESULTS: The performance of ethanol fermentation was affected by calcium chloride concentration, N‐vinyl‐2‐pyrrolidone grafted onto the sodium alginate, sugar concentration and the percentage of immobilized cell beads. These effects were optimized to give maximum ethanol production. Ethanol production was accelerated when sodium alginate polymer was modified with N‐vinyl‐2‐pyrrolidone. The maximum concentration, productivity and yield of ethanol were 69.68 g L−1, 8.71 g L−1 h−1 and 0.697 g g−1, respectively.

CONCLUSION: The new polymeric matrix, when compared with sodium alginate, showed better ethanol production due to the hydrophilic property of N‐vinyl‐2‐pyrrolidone. The results suggest that the proposed method for immobilization of Saccharomyces cerevisiae has potential in industrial applications of the ethanol production process. Copyright © 2011 Society of Chemical Industry
Selective CO oxidation over monolithic AuMgO/Al2O3 catalysts
Authors: Özdemir Seval , Önsan Zeynep Ilsen , Yıldırım Ramazan
Published: June 2011

BACKGROUND: Selective CO oxidation was studied in a hydrogen‐rich environment over monolithic Au/MgO/Al2O3 catalysts at 50–150 °C. The wash‐coating of cordierite monoliths with colloidal Al2O3 was followed by wet impregnation of MgO; the subsequent deposition of Au was achieved using various methods. All catalysts were characterized using ICP and ESEM.

RESULTS: Homogenous deposition‐precipitation was found to be the best Au loading method among those tested for monoliths. The CO conversion over 1%(w/w) Au/1.25%(w/w) MgO/Al2O3 was ca 80% at 90 °C. Increasing the Au content of the catalyst from 0.16 to 1.0%(w/w) increased CO conversion and shifted the required temperature to lower values. A similar trend was also observed for maximum CO conversion at increasing W/FCO ratios. The addition of MgO was beneficial for CO conversion.

CONCLUSION: Although CO conversion of ca 80% was lower than that achieved with particulate catalysts, it is high enough as a starting point for further improvement considering the superiority of monolithic supports for practical applications. Copyright © 2011 Society of Chemical Industry
The paratympanic organ: a barometer and altimeter in the middle ear of birds?
Authors: von Bartheld Christopher S. , Giannessi Francesco
Published: June 2011

A century has passed since the discovery of the paratympanic organ (PTO), a mechanoreceptive sense organ in the middle ear of birds and other tetrapods. This luminal organ contains a sensory epithelium with typical mechanosensory hair cells and may function as a barometer and altimeter. The organ is arguably the most neglected sense organ in living tetrapods. The PTO is believed to be homologous to a lateral line sense organ, the spiracular sense organ of nonteleostean fishes. Our review summarizes the current state of knowledge of the PTO and draws attention to the astounding lack of information about the unique and largely unexplored sensory modality of barometric perception. J. Exp. Zool. (Mol. Dev. Evol.) 316:402–408, 2011. © 2011 Wiley‐Liss, Inc.
Hepatic control elements promote long‐term expression of human coagulation factor IX gene in hydrodynamically transfected mice
Authors: Kim Hong Sung , Kim Jong Chul , Lee Yeon Kyung , Kim Jung Seok , Park Yong Serk
Published: June 2011

Background

Long‐term expression of the delivered target gene is critical for successful gene therapy. Recently, hepatic control region I (HCR I) originating from the apolipoprotein (apo)C‐I pseudogene was shown to be a critical element for long‐term gene expression in the liver of mice. HCR II is another hepatic control region of apoC‐I.

Methods

HCR I, HCR II and HCR I/II‐containing plasmids encoding factor IX were prepared and hydrodynamically transferred into the liver of normal and hemophilia B mice. Factor IX expression, clotting activity and formation of antibodies against the expressed gene product were compared.

Results

HCR I‐, HCR II‐ and HCR I/II‐containing plasmids all induced long‐term gene expression in both normal and hemophilia B mice. Post‐transfection factor IX expression in the hemophilia B mice remained above 500 ng/ml for 210 days. Antibodies against human factor IX were detected at a low level in the serum, although they had no effect on the levels and clotting activity of the expressed factor IX.

Conclusions

We have shown in mouse models that hydrodynamic transfection of pBS‐HCRII‐HP‐FIXA and pBS‐HCRI/II‐HP‐FIXA was able to induce and maintain the expression and clotting activity of human factor IX for a long period of time at a potentially therapeutic level. With an appropriate delivery system, this type of plasmid vector could be clinically useful for the hepatic expression of therapeutic genes including human factor IX. Copyright © 2011 John Wiley & Sons, Ltd.
Gene therapy with adenovirus‐delivered indoleamine 2,3‐dioxygenase improves renal function and morphology following allogeneic kidney transplantation in rat
Authors: Vavrincova‐Yaghi Diana , Deelman Leo E. , van Goor Harry , Seelen Marc , Kema Ido P. , Smit‐van Oosten Annemieke , de Zeeuw Dick , Henning Robert H. , Sandovici Maria
Published: June 2011

Background

Indoleamine 2,3‐dioxygenase (IDO), the rate‐limiting enzyme in the tryptophan catabolism, has recently emerged as an important immunosuppressive enzyme involved in the regulation of both physiologic (maternal tolerance), as well as pathologic (neoplasia, autoimmune diseases, asthma) processes. Accumulating evidence points to a role for IDO in suppressing T‐cell responses, thereby promoting tolerance. In the present study, we investigate the effects of adenovirus‐mediated gene therapy with IDO on the acute rejection of the transplanted kidneys.

Methods

The experiments were performed in a rat Fisher to Lewis acute renal rejection model. RGD modified adenovirus carrying IDO gene (RGD‐AdTIDO, n = 9) or RGD modified adenovirus carrying green fluorescent protein gene (RGD‐AdTL, n = 8) were injected into the renal artery of the donor kidney before transplantation. A group receiving saline (n = 8) served as control. Rats were sacrificed after 7 days.

Results

Successful gene delivery was confirmed with real‐time polymerase chain reaction and immunohistochemistry. RGD‐AdTIDO significantly decreased elevated plasma creatinine (93.7 ± 18.9 µmol/l) compared to the RGD‐AdTL (248.2 ± 43.6 µmol/l) and saline (228.3 ± 46.4 µmol/l) treated rats. Moreover, RGD‐AdTIDO therapy diminished the infiltration of CD8+ T cells and macrophages into the graft and reduced renal interstitial pre‐fibrosis. Also, it limited the up‐regulation of kidney injury molecule‐1, interleukin (IL)‐2, IL‐17 and transforming growth factor‐β mRNA expression, and increased foxp3 mRNA expression compared to controls.

Conclusions

RGD‐AdTIDO therapy improves renal function and morphology in a clinically relevant model of acute rejection. Copyright © 2011 John Wiley & Sons, Ltd.
Mechanisms of polyethylenimine‐mediated DNA delivery: free carrier helps to overcome the barrier of cell‐surface glycosaminoglycans
Authors: Hanzlíková Martina , Ruponen Marika , Galli Emilia , Raasmaja Atso , Aseyev Vladimir , Tenhu Heikki , Urtti Arto , Yliperttula Marjo
Published: June 2011

Background

Polyethylenimine (PEI) polyplexes mediate efficient gene transfer only at high +/− charge ratios at which free noncomplexed PEI is present. The excess of PEI gives polyplexes a positive surface charge that plays a role in polyplex binding on the cell membrane. Although positively charged PEI polyplexes are known to interact with anionic cell‐surface glycosaminoglycans (GAGs), the exact role of free PEI in such interactions is unclear.

Methods

Chinese hamster ovary wild‐type cells and mutants lacking cell‐surface GAGs were transfected with marker genes using PEI polyplexes with and without free PEI. The total amount of cell‐associated plasmid DNA (pDNA) delivered by polyplexes was determined by quantitative real‐time PCR and transgene expression was determined using β‐galactosidase and luciferase assays.

Results

Transfection activity of polyplexes without free PEI in cells expressing cell‐surface GAGs was low even though pDNA was delivered to cells. In the absence of cell‐surface GAGs, polyplexes without free PEI had high transfection efficacy. This indicates that the cell‐surface GAGs inhibit transfection by purified polyplexes. PEI polyplexes with free carrier mediated transfection in both normal and GAG‐deficient cells because free PEI overcomes the inhibitory effect of cell‐surface GAGs on transfection. The intracellular elimination of pDNA was faster in the presence of GAGs and, despite improved transfection, free PEI reduced pDNA association with the cells.

Conclusions

Free PEI is essential for minimizing the undesirable binding of polyplexes to cell‐surface GAGs that have a negative impact on transfection. The same mechanism may be important in transfections with other polyplexes that require high charge ratios for transfection. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis and antimicrobial activity of some novel substituted 1,2,4‐triazoles bearing 1,3,4‐oxadiazoles or pyrazoles
Authors: Kalhor Mehdi , Mobinikhaledi Akbar , Dadras Akbar , Tohidpour Maryam
Published: June 2011

Several derivatives of substituted 1,2,4‐triazole bearing the pyrazole (or oxadiazole) ring were synthesized via the reaction of 2,4‐dihydro‐4‐benzyl‐5‐(isomeric pyridyl)‐3H‐1,2,4‐triazole‐3‐thione 1a, 1b, 1c with ethyl chloroacetate, hydrazine hydrate, and acetyl acetone (or CS2/KOH) in absolute ethanol. The intermediate then undergoes an intramolecular cyclization in acidic medium. The newly synthesized compounds 4a, 4b, 4c to 7a, 7b, 7c were characterized using IR, NMR, and MS Spectroscopy. Some of the synthesized compounds 4,5,7a, 7b, 7c were evaluated for their antibacterial and antifungal activities. Most of these compounds indicated activity comparable to Gentamycine. Also some of them are more active than Tolnaftate, a known antifungal drug. J. Heterocyclic Chem., (2011)
Male reproductive apparatus and spermatophore morphology of the hermit crabs Pagurus brevidactylus and P. criniticornis (Anomura, Paguridae)
Authors: Fantucci Marina Zilio , Mantelatto Fernando Luis
Published: June 2011

Spermatozoa of most crustacean species are nonmotile and are packed into spermatophores. In Decapoda, spermatophores are highly variable in morphology and can be useful in the solving of taxonomic and systematic questions, especially among the Anomura. In this study, the morphology and morphometry of the spermatophores of the western Atlantic hermit crabs Pagurus brevidactylus and P. criniticornis are described. The abdomen of fresh male specimens was dissected to expose the reproductive system and to extract the spermatophores, which were analyzed by stereoscopic, light, and scanning electron microscopy. The vas deferens can be divided macroscopically in three regions, all of them containing spermatophores. Tripartite spermatophores are composed of an elongated cylindrical main ampulla, a triangular accessory ampulla, a narrow cylindrical peduncle, and a round pedestal. Dimensions of the spermatophore components are positively correlated to the size of the crab. Morphological patterns observed in this study resemble those of other pagurid hermit crabs investigated to date. The morphological character distribution confirms classifications based on adult morphology and molecular analysis. J. Morphol. 2011. © 2011 Wiley‐Liss, Inc.
Evaluating the core: Critical assessment of core self‐evaluations theory
Authors: Chen Gilad
Published: June 2011

In 1997, Judge, Locke, and Durham published the core self‐evaluations (CSE) theory proposing that a multidimensional CSE construct, composed of emotional stability, self‐esteem, locus of control, and generalized self‐efficacy, accounts for individual differences in job satisfaction as well as in other organizational behavior outcomes. In this article, I argue that, despite ample evidence in support of the predictive validity of the CSE construct, the adequacy of including emotional stability, self‐esteem, locus of control, and generalized self‐efficacy as indicators of the CSE construct may be questionable, and I review evidence that points to limited convergent and discriminant validity of the CSE construct. I conclude the article with a few recommendations for advancing CSE theory and research. Copyright © 2011 John Wiley & Sons, Ltd.
Effects of aging and degeneration on the human intervertebral disc during the diurnal cycle: A finite element study
Authors: Massey Christopher J. , van Donkelaar Corrinus C. , Vresilovic Edward , Zavaliangos Antonios , Marcolongo Michele
Published: June 2011

A significant biochemical change that takes place in intervertebral disc degeneration is the loss of proteoglycans in the nucleus pulposus. Proteoglycans attract fluid, which works to reduce mechanical stresses in the solid matrix of the nucleus and provide a hydrostatic pressure to the annulus fibrosus, whose fibrous nature accommodates this stress. Our goals are to develop an osmo‐poroelastic finite element model to study the relationship between proteoglycan content and the stress distribution within the disc and to analyze the effects of degeneration on the disc's diurnal mechanical response. Stress in the annulus increased with degeneration from ∼0.2 to 0.4 MPa, and an increase occurred in the center of the nucleus from 1.2 to 1.6 MPa. The osmotic pressure in the central nucleus region decreased the most with degeneration, from ∼0.42 to ∼0.1 MPa in a severely dehydrated disc. A 3% decrease in diurnal fluid lost with degeneration equated to ∼21% decrease in fluid exchange, and hence a decrease in nutrients that require convection to enter the disc. We quantified the increases in internal stresses in the nucleus and annulus throughout the various stages of degeneration, suggesting that these changes lead to further remodeling of the tissue. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 30:122–128, 2012
Stray light in low wavenumber Raman spectra and secondary maxima of grating diffraction
Authors: Shuang B. , Wang C. X. , Xia L. , Xu B. , Zhang S. L.
Published: June 2011

The origin of the stray light appearing in the low wavenumber Raman spectra was studied on a double monochromator with a charge coupled device (CCD) detector by theoretical calculations and experimental observations. It is verified that the effect of the secondary maxima of the diffraction grating on the spectrum cannot be ignored, and the secondary maxima of Rayleigh scattering lead to the stray light in low wavenumber Raman spectra. The dependence of operating parameters for a double monochromator with a CCD detector working in the additive mode on the spectral feature has been calculated and experimentally observed. This may give a quantitative suggestion for proper choice of operating parameters that can efficiently suppress stray light in low wavenumber Raman spectra. Copyright © 2011 John Wiley & Sons, Ltd.
Ion–polymer and ion–ion interaction in PEO‐based polymer electrolytes having complexing salt LiClO4 and/or ionic liquid, [BMIM][PF6]
Authors: Chaurasia Sujeet K. , Singh Rajendra K. , Chandra S.
Published: June 2011

Ion–polymer and ion–ion association in polymer electrolyte films of PEO complexed with salt LiClO4, ionic liquid (1‐butyl‐3‐methylimidazolium hexafluorophosphate, BMIMPF6) and (LiClO4 + BMIMPF6) have been studied by laser Raman spectroscopy. The cations (Li+ and/or BMIM+) of the dopant salt/IL are shown to complex with the ether oxygen of the polymer backbone (i.e. COC bond of PEO). The polymer–cation complexation results in the appearance of an additional peak at ∼1131 cm−1 apart from the COC stretching vibrations of PEO at ∼1062 and 1141 cm−1. This peak due to polymer–cation complexation is relatively strong for LiClO4 than BMIMPF6, indicating stronger interaction for the former. In the PEO:LiClO4 and PEO:BMIMPF6 spectra, Raman peaks at 937 and 747 cm−1, respectively related to Li+· ClO and BMIM+· PF ‘contact ion pairs’, have also been observed as a result of ion–ion association. In the polymer electrolyte PEO:LiClO4 + BMIMPF6 which contained two different anions, viz. ClO and PF, an interesting observation of the formation of ‘cross contact ion pairs’ viz. Li+· PF and BMIM+· ClO is also reported. Copyright © 2011 John Wiley & Sons, Ltd.
Investigation of adhesive–dentin interfaces using Raman microspectroscopy and small angle X‐ray scattering
Authors: Bayarı Sevgi Haman , Krafft Christoph , İde Semra , Popp Jürgen , Guven Gunseli , Cehreli Zafer C. , Soylu Elif Hilal
Published: June 2011

Human dentin specimens were treated with two different etch‐and‐rinse adhesives, Single Bond 2 (SB2) and Prime & Bond NT (PBNT), and two composite resins, TPH and P60. Cross‐sectional samples, approximately 1 mm thick, were analyzed with Raman line mapping and imaging across the dentin–adhesive–composite interface. The integrated intensities of selected bands associated with adhesive, organic material, composite and hydroxyapatite of dentin were calculated to determine the distribution of adhesive infiltration into demineralized dentin. The results were compared with the enamel‐adhesive composite interface. The demineralized zone was smaller in the enamel‐adhesive interface than in the dentin–adhesive interface. The region of collagen‐adhesive crosslinking was wider in the PBNT adhesive than in the SB2 adhesive. However, a gap at the dentin–PBNT composite interface, which was not observed at the dentin–SB2 composite interface, might compromise the dentin–restoration bond. K‐means cluster analysis of the Raman images confirmed the findings. The ultrastructure of the dentin–resin interface was studied using scanning electron microscopy. Small‐angle X‐ray scattering was also applied to reveal and quantify fine‐scale structural features. SB2 adhesive was found to diffuse more into demineralized dentin along with greater nanosized aggregations in the hybrid layer. Copyright © 2011 John Wiley & Sons, Ltd.
Analysis of cold denaturation mechanism of β‐lactoglobulin and comparison with thermal denaturation from Raman spectroscopy investigations
Authors: Hédoux Alain , Seo Jeong‐Ah , Guinet Yannick , Paccou Laurent
Published: June 2011

Cold‐ and heat‐induced β‐lactoglobulin (BLG) transformations have been analyzed in the presence of 4 M urea, from Raman spectroscopy investigations carried out simultaneously in the low wavenumber range (10–400 cm−1) and in the amide I region (1500–1800 cm−1). These investigations show common features between the denaturation processes at low and high temperatures. The denatured states are reached via an intermediate state characterized by a soft tertiary structure without detectable conformational changes. This intermediate is intimately connected with a tetrahedral hydrogen‐bond structure of water which extends over a limited range. It is shown that the disruption of the hydrogen‐bond network of D2O has an important consequence on the solvent dynamics, which controls protein dynamics and is characterized by an anharmonic behavior. By monitoring the amide I mode, conformational changes are detected at low temperature (below 5 °C) and determined to be similar to those detected at high temperature in the presence of urea near 65 °C, and in the absence of urea near 80 °C. The conformational changes are described as a loss of α‐helix structures and a concomitant formation of β‐sheets. The temperature dependence of the amide I wavenumber in BLG dissolved in the 4 M urea aqueous solution was interpreted on the basis of a two‐state model, leading to the protein stability curve related to its molecular conformation. Copyright © 2011 John Wiley & Sons, Ltd.
Prognostic significance of postoperative complications after hepatectomy for hepatocellular carcinoma
Authors: Okamura Yukiyasu , Takeda Shin , Fujii Tsutomu , Sugimoto Hiroyuki , Nomoto Shuji , Nakao Akimasa
Published: June 2011

Background

Hepatectomy is one of the best curative therapies for hepatocellular carcinoma (HCC). The negative impact of postoperative complications on long‐term survival has been investigated in patients with several kinds of cancers. To clarify the impact of postoperative complications on long‐term survival in patients who undergo hepatectomy for HCC, we conducted a comparative analysis of 376 patients using the modified Clavien classification and identified the predictors of postoperative complications.

Methods

Patients were assigned into two groups: those with (N = 177) and those without complications (N = 199). The clinical data, surgical outcome, and long‐term survival of patients were analyzed retrospectively.

Results

The cumulative overall survival rates of the patients with complications were significantly less than those of the patients without complications (P < 0.01). Multivariate logistic regression analysis revealed that intraoperative blood transfusion (P = 0.04), longer operation time (P = 0.02), use of Pringle's maneuver (P < 0.01), and use of the thoraco‐abdominal approach (P = 0.01) were independent risk factors for postoperative complications.

Conclusions

Postoperative complications (major or minor) are one of prognostic indicators in hepatectomy for HCC. The present study suggests that high quality surgical technique to minimize complications will improve the prognosis of HCC. J. Surg. Oncol. 2011; 104:814–821. © 2011 Wiley Periodicals, Inc.
Prognostic impact of MMP‐2 and MMP‐9 expression in pathologic stage IA non‐small cell lung cancer
Authors: Shao Wenlong , Wang Wei , Xiong Xin‐guo , Cao Christopher , Yan Tristan D. , Chen Guoqin , Chen Hanzhang , Yin Weiqiang , Liu Jun , Gu Yingying , Mo Mingcong , He Jianxing
Published: June 2011

Background

The purpose of the present study was to assess the value of matrix metalloproteinase (MMP)‐2 and MMP‐9 expression and other potential prognostic factors in predicting the clinical outcome of patients after definitive surgery for pathologic stage IA non‐small cell lung cancer (NSCLC).

Methods

One hundred and forty‐six consecutive and non‐selected patients who underwent definitive surgery for stage IA NSCLC were included in this study. Formalin‐fixed paraffin‐embedded specimens were stained for MMP‐2 and MMP‐9, which were statistically evaluated for their prognostic value and other clinicopathological parameters.

Results

Of the 146 patients studied, 102 (69.9%) cases were classified as having high expression for MMP‐2. A total of 89 carcinomas (61.0%) had high expression for MMP‐9. MMP‐9 expression correlated with Eastern Cooperative Oncology Group (ECOG) performance status, pT stage, and differentiation (P = 0.005, <0.001, and <0.001, respectively). Vessel invasion, pT stage, and MMP‐9 expression maintained their independent prognostic influence on overall survival (P = 0.037, <0.001, and <0.001, respectively).

Conclusions

From results of our relatively large database, MMP‐9 may be considered as a viable biomarker that can be used in conjunction with other prognostic factors such as vessel invasion and pT stage to predict the prognosis of patients with completely resected pathologic stage IA NSCLC. J. Surg. Oncol. 2011; 104:841–846. © 2011 Wiley Periodicals, Inc.
Prognostic significance of serum miRNA‐21 expression in human non‐small cell lung cancer
Authors: Wang Zhao‐Xia , Bian Hai‐Bo , Wang Ji‐Rong , Cheng Zhi‐Xiang , Wang Ke‐Ming , De Wei
Published: June 2011

Background

Deregulation of microRNAs (miRNAs) plays important roles in tumor progression. The aim of this study was to investigate miR‐21 expression in serum of non‐small cell lung cancer (NSCLC) and its correlation with prognosis of NSCLC patients.

Methods

Dysregulated miRNAs in NSCLC serum were identified by microarray. MiR‐21 expression in NSCLC and control serum was detected by TaqMan RT‐PCR assay. The correlation of serum miR‐21 with clinicopathological factors of NSCLC patients was analyzed. Furthermore, the prognostic significance of serum miR‐21 was analyzed by using Kaplan–Meier curves with log‐rank tests and a Cox proportional hazard model.

Results

The level of miR‐21 expression was higher in NSCLC serum samples than in control serum samples (P < 0.01). High serum miR‐21 was significantly correlated with tumor‐node metastases stage and lymph node metastasis of NSCLC patients (P = 0.016 and 0.026, respectively). The 3‐year actuarial overall survival rates in NSCLC patients with high serum miR‐21 expression (39.8%) was significantly shorter than those with low serum miR‐21 expression (58.2%; P < 0.001). Furthermore, univariate and multivariate analyses for overall survival showed that serum miR‐21 expression was an independent prognostic factor for NSCLC patients (P = 0.015, RR = 2.01, 95% CI: 1.78–3.26).

Conclusion

Serum miR‐21 expression might be useful as a prognostic marker for NSCLC patients. J. Surg. Oncol. 2011; 104:847–851. © 2011 Wiley Periodicals, Inc.
Brain, the last fortress of sarcoma: Similar dismal outcome but discrepancy of timing of brain metastasis in bone and soft tissue sarcoma
Authors: Chou Yi‐Sheng , Liu Chun‐Yu , Chen Wei‐Ming , Chen Tain‐Hsiung , Chen Paul Chih‐Hsueh , Wu Hung‐Ta Hondar , Shiau Cheng‐Ying , Wu Yu‐Chung , Liu Chien‐Lin , Chao Ta‐Chung , Tzeng Cheng‐Hwai , Wong Tai‐Tong , Yen Chueh‐Chuan
Published: June 2011

Background and Objective

Brain metastasis is a rare but dismal event in sarcomas. However, the pattern of occurrence and the prognostic factors associated with post‐brain metastasis survival (PBMS) are not yet well‐characterized.

Methods

Sarcoma patients treated at one institute within 10‐year period were retrospectively reviewed and those with brain metastasis were identified. The incidence of brain metastasis was demonstrated by case per person‐years and cumulative incidence curves. Univariate factors associated with PBMS were analyzed.

Results

Among 611 sarcoma patients, 20 (3.3%) developed brain metastasis. Alveolar soft part sarcoma (ASPS) and osteosarcoma were the most common subtypes. Overall, the cumulative incidence was 3.9% at 5 years and 8.4% at 10 years. However, the incidence in STS patients continued to rise up to 10 years after primary diagnosis, whereas it reached a plateau in bone sarcoma patients at 3 years. Median PBMS was 1.67 months. Univariate factors associated with better PBMS included ASPS histology, initial surgical treatment, and brain irradiation for non‐surgically treated patients.

Conclusion

Our study revealed a discrepancy in the timing of occurrence of brain metastasis between STS and bone sarcoma. However, patients with brain metastasis had a poor prognosis, implicating the brain as the last fortress of sarcoma. J. Surg. Oncol. 2011; 104:765–770. © 2011 Wiley Periodicals, Inc.
Chemical correlation between Shuanghuanglian injection and its three raw herbs by LC fingerprint
Authors: Liu Lijuan , Jiang Wenhong , Zhang Lijie , Li Fang , Zhang Qingbo
Published: June 2011

Shuanghuanglian injection, a famous composite formula in China, is a combination of Flos lonicerae japonicae, Radix scutellariae and Fructus forsythiae. To develop a method to overall evaluate the correlation between the formula and its three raw herbs, the representative LC fingerprint of Shuanghuanglian injection was established from 12 batches of samples. Ten peaks were selected as the common peaks to evaluate the similarities of different samples from different manufacturers. Hierarchical clustering analysis was used as a powerful pattern recognition tool to identify and classify Shuanghuanglian injection from different factories. In addition, chemical correlation between the formula and the three raw herbs was evaluated qualitatively through comparison of their chromatograms under the same HPLC conditions. The results showed that peak 1, 2, 3 and 9 in the formula fingerprint were characteristic components of Flos lonicerae japonicae, peaks 5, 6 and 8 were that of F. forsythiae, peak 10 was that of R. scutellariae, while peak 7 was the common component of Flos lonicerae japonicae and F. forsythiae, peak 4 was addressed to F. forsythiae and it was also the product of the manufacturing procedure.
HPLC‐ELSD analysis of spectinomycin dihydrochloride and its impurities
Authors: Zhou Junyi , Zhang Lin , Wang Yan , Yan Chao
Published: June 2011

A simple, rapid and reliable reversed‐phase ion‐pair chromatography method by HPLC coupled to an evaporative light scattering detector (ELSD) has been developed to simultaneously determine chloride, spectinomycin and its related substances in a sample. The column was a TSKgel ODS‐100V. The mobile phase was ACN/aqueous solution of 15 mM ammonium acetate adjusted with TFA to pH 3.0 (2:98 v/v), in an isocratic mode. The drift tube temperature was set at 50°C and the nebulizing gas flow rate of air was 3.5 L/min for ELSD detection. Almost all of the reported degradation compounds of spectinomycin such as actinamine, actinospectinoic acid and biosynthesis intermediates such as dihydrospectinomycin diastereoisomers were baseline separated. MS was utilized for the identification of spectinomycin and its seven related substances. The method for the assay of spectinomycin was successfully validated with respect to accuracy, precision (RSD less than 2%), linearity (throughout the linear range 0.025–3 mg/mL, r=0.9993), sensitivity (LOD: 100 ng on column) and robustness. The experimental results demonstrated that the simultaneous determination of chloride, spectinomycin and related substances is feasible in a single run, which suggests applicability in routine assays.
Analysis of β‐blockers in groundwater using large‐volume injection coupled‐column reversed‐phase liquid chromatography with fluorescence detection and liquid chromatography time‐of‐flight mass spectrometry
Authors: Galera María M. , Vázquez Piedad P. , Vázquez María del Mar P. , García María Dolores G. , Amate Carmen F.
Published: June 2011

Atenolol, nadolol, metoprolol, bisoprolol and betaxolol were simultaneously determined in groundwater samples by large‐volume injection coupled‐column reversed‐phase liquid chromatography with fluorescence detection (LVI‐LC‐LC‐FD) and liquid chromatography‐time‐of‐flight mass spectrometry (LC‐TOF‐MS). The LVI‐LC‐LC‐FD method combines analyte isolation, preconcentration and determination into a single step. Significant reductions in costs for sample pre‐treatment (solvent and solid phases for clean up) and method development times are also achieved. Using LC‐TOF‐MS, accurate mass measurements within 3 ppm error were obtained for all of the β‐blockers studied. Empirical formula information can be obtained by this method, allowing the unequivocal identification of the target compounds in the samples. To increase the sensitivity, a solid‐phase extraction step with Oasis MCX cartridge was carried out yielding recoveries of 79–114% (n=5) with RSD 2–7% for the LC‐TOF‐MS method. SPE gives a high purification of β‐blockers compared with the existing methods. A 100% methanol wash was allowed for these compounds with no loss of analytes. Limit of quantification was 1–7 ng/L for LVI‐LC‐LC‐FD and 0.25–5 ng/L for LC‐TOF‐MS. As a result of selective extraction and effective removal of coextractives, no matrix effect was observed in LVI‐LC‐LC‐FD and LC‐TOF‐MS analyses. The methods were applied to detect and quantify β‐blockers in groundwater samples of Almería (Spain).
Global detection and identification of components from crude and processed traditional Chinese medicine by liquid chromatography connected with hybrid ion trap and time‐of‐flight‐mass spectrometry
Authors: Cao Gang , Zhang Chengrong , Zhang Yun , Cong Xiaodong , Cai Hao , Cai Baochang , Li Xiaomeng , Yao Jinting
Published: June 2011

We herein present a chemical profiling method to efficiently process the information acquired by ultra fast liquid chromatography (UFLC)‐electrospray ionization source in combination with hybrid ion trap and high‐resolution time‐of‐flight mass spectrometry (UFLC‐(ESI)‐IT‐TOF/MS), facilitating the structural determination of serial components contained in crude or processed traditional Chinese medicine (TCM). Under the optimized UFLC and IT‐TOF‐MSn conditions, over 39 compounds were separated and detected in crude or processed Fructus corni within 25 min. The components were identified by comparing the mass spectra and retention time with reference compounds, or tentatively assigned by elucidating low‐energy collision‐induced dissociation (CID) fragment ions and matching empirical molecular formula with that of the published compounds. Several factors in the processing procedure were examined. The experimental results demonstrate that the chemical reactions that occurred in the processing procedure can be used to elucidate the processed mechanism of F. corni, which is regularly affected by the processing conditions. This study provides a novel approach and methodology to identify the complicated components from various complex mixtures such as crude TCM, processed TCM, and biological samples. It can be used as a valid analytical method for further understanding the processing mechanism of TCM, along with the intrinsic quality control of TCM and its processed product.
Comparison of different liquid chromatography stationary phases in LC‐HRMS metabolomics for the detection of recombinant growth hormone doping control
Authors: Boyard‐Kieken Fanny , Dervilly‐Pinel Gaud , Garcia Patrice , Paris Anne‐Christelle , Popot Marie‐Agnès , le Bizec Bruno , Bonnaire Yves
Published: June 2011

Growth hormone (GH) is a polypeptide suspected of being used in horse racing to speed up physical performances. Despite scientific advances in the recent years, the control of its administration remains difficult. In order to improve it, a metabolomics study through LC‐high resolution mass spectrometry measurements was recently initiated to assess the metabolic perturbations caused by recombinant equine growth hormone administration. Few tens of ions not identified structurally were highlighted as compounds responsible for the modification of metabolic profiling observed in treated animals. This previous work was based on the use of Uptisphere Strategy NEC as the chromatographic column. In parallel, more and more metabolomics studies showed the interest of the use of new chromatographic supports such as hydrophilic interaction chromatography for the analysis of polar compounds. It is in this context that an investigation was conducted on Uptisphere HDO and Luna hydrophilic interaction chromatography stationary phases to generate and process urinary metabolomics fingerprints, which could allow to establish a comparison with Uptisphere Strategy NEC. The chromatographic column the most adapted for the detection of new biomarkers of GH administration has been used to set up a relevant statistical model based on the analysis of more than hundred biological samples.
Simultaneous determination of aliskiren and hydrochlorothiazide from their pharmaceutical preparations using a validated stability‐indicating MEKC method
Authors: Sangoi Maximiliano S. , Wrasse‐Sangoi Micheli , Oliveira Paulo R. , Rolim Clarice M. B. , Steppe Martin
Published: June 2011

A stability‐indicating MEKC method was developed and validated for the simultaneous determination of aliskiren (ALI) and hydrochlorothiazide (HCTZ) in pharmaceutical formulations using ranitidine as an internal standard (IS). Optimal conditions for the separation of ALI, HCTZ and its major impurity chlorothiazide (CTZ), IS and degradation products were investigated. The method employed 47 mM Tris buffer and 47 mM anionic detergent SDS solution at pH 10.2 as the background electrolyte. MEKC method was performed on a fused‐silica capillary (40 cm) at 28°C. Applied voltage was 26 kV (positive polarity) and photodiode array (PDA) detector was set at 217 nm. The method was validated in accordance with the ICH requirements. The method was linear over the concentration range of 5–100 and 60–1200 μg/mL for HCTZ and ALI, respectively (r2>0.9997). The stability‐indicating capability of the method was established by enforced degradation studies combined with peak purity assessment using the PDA detection. Precision and accuracy evaluated by RSD were lower than 2%. The method proved to be robust by a fractional factorial design evaluation. The proposed MEKC method was successfully applied for the quantitative analysis of ALI and HCTZ both individually and in a combined dosage tablet formulation to support the quality control.
Determination of enantiomeric purity of S‐amlodipine by chiral LC with emphasis on reversal of enantiomer elution order
Authors: Dossou Katina S. S. , Edorh Patrick A. , Chiap Patrice , Chankvetadze Bezhan , Servais Anne‐Catherine , Fillet Marianne , Crommen Jacques
Published: June 2011

An LC method was developed and prevalidated for the enantiomeric purity determination of S‐amlodipine in polar organic solvent chromatography using a chlorine‐containing cellulose‐based chiral stationary phase (CSP). The concentration of formic acid (FA) (0.01–0.2%) in the mobile phase containing acetonitrile as the main solvent was found to influence the elution order of amlodipine enantiomers as well as the enantioresolution. A reversal of the enantiomer elution order of amlodipine was only observed with chiral stationary phases with both electron‐withdrawing (chloro) and electron‐donating groups (methyl) on the phenyl moieties of the chiral selector, namely cellulose tris(3‐chloro‐4‐methylphenylcarbamate) and cellulose tris(4‐chloro‐3‐methylphenylcarbamate). The highest enantioresolution (Rs: 4.1) value was obtained at the lowest FA concentration (0.01%) using cellulose tris(4‐chloro‐3‐methylphenylcarbamate) as the chiral selector and the enantiomeric impurity, R‐amlodipine, eluted first under these conditions. Therefore, the mobile phase selected for the prevalidation of the method consisted of ACN/0.1% DEA/0.01% FA and the temperature was set at 25°C. The method was prevalidated by means of the strategy based on the total measurement error and the accuracy profile. The method was found to be selective and the limit of quantification was found to be about 0.05% for R‐amlodipine, while the limit of detection was close to 0.02%.