bluuebunny/crossref_metadata_2025 huggingface dataset:
In vitro biological evaluation of electrospun cellulose acetate fiber mats containing asiaticoside or curcumin
Authors: Suwantong Orawan , Ruktanonchai Uracha , Supaphol Pitt
Published: April 2010

Ultra‐fine cellulose acetate (CA; Mw ≈ 30,000 Da; degree of acetyl substitution ≈ 2.4) fiber mats containing either asiaticoside [from the plant Centella asiatica (L.); either in the form of a crude extract (CACE) or pure substance (PAC)] or curcumin (CM; from the plant Curcuma longa L.) were successfully prepared. The proposed use of these materials is as topical/transdermal patches or wound dressings. Here, the potential for use of these herb‐loaded CA fiber mats as wound dressings was evaluated in terms of the stability and the antioxidant activity of the as‐loaded herbal substances, the ability to support both the attachment and the proliferation of fibroblasts and the ability of the cultured fibroblasts to synthesize collagen. Normal human dermal fibroblasts (NHDF) were used as the reference fibroblastic cells. The results showed that the as‐loaded herbal substances were stable even after the herb‐loaded CA fiber mats had been aged either at room temperature or at 40°C for a period of up to 4 months. The inclusion of asiaticoside [either 2% (w/w) CACE or 40% (w/w) PAC] rendered the resulting CA fiber mats their superiority in supporting the attachment, promoting the proliferation, and upregulating the production of collagen of the seeded and/or the cultured NHDF to the corresponding solvent‐cast films and the neat CA fiber mats. On the other hand, the presence of CM imparted the antioxidant activity to the resulting CA fiber mats. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
In vitro evaluation of inhalable isoniazid‐loaded surfactant liposomes as an adjunct therapy in pulmonary tuberculosis
Authors: Chimote G. , Banerjee R.
Published: April 2010

In this study, exogenous pulmonary surfactant was evaluated as an inhalable drug carrier for antitubercular drug isoniazid (INH). Isoniazid‐entrapped liposomes of dipalmitoylphosphatidylcholine (DPPC) (the most abundant lipid of lung surfactant and exogenous surfactant) were developed and evaluated for size, drug entrapment, release, in vitro alveolar deposition, biocompatibility, antimycobacterial activity, and pulmonary surfactant action. Isoniazid‐entrapped DPPC liposomes were about 750 nm in diameter and had entrapment efficiency of 36.7% ± 1.8%. Sustained release of INH from DPPC liposomes was observed over 24 h. In vitro alveolar deposition efficiency using the twin impinger exhibited ∼25–27% INH deposition in the alveolar chamber upon one minute nebulization using a jet nebulizer. At 37°C, the formulation had better pulmonary surfactant function with quicker reduction of surface tension on adsorption (36.7 ± 0.4 mN/m) than DPPC liposomes (44.7 ± 0.6 mN/m) and 87% airway patency was exhibited by the formulation in a capillary surfactometer. The formulation was biocompatible and had antimycobacterial activity. The isoniazid‐entrapped DPPC liposomes could fulfill the dual purpose of pulmonary drug delivery and alveolar stabilization due to antiatelectatic effect of the surfactant action which can improve the reach of antitubercular drug INH to the alveoli. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010.
Acetaldehyde plasma polymer‐coated PET fibers for endothelial cell patterning: Chemical, topographical, and biological analysis
Authors: Hadjizadeh Afra
Published: April 2010

The objective of this study was to produce fibrous biomaterials with cell adhesive and cell repulsive capabilities for biomedical applications. To this aim, the surface of 100‐μm diameter polyethylene terephthalate fibers were functionalized with acetaldehyde plasma polymer deposition followed by carboxymethyl dextran grafting onto the aldehyde‐coated surfaces via a polyethyleneimine interlayer. The performance of the surface modification steps were confirmed by surface chemical composition analysis using X‐ray photoelectron spectroscopy, surface topography analysis by atomic force microscopy, and scanning electron microscopy. The acetaldehyde plasma polymer‐coated and polyethyleneimine‐grafted substrates promoted human umbilical vein endothelial cells attachment, spreading and actin filaments/focal adhesions formation. In contrast, carboxymethyl dextran‐grafted substrates resisted cell adhesion. These observations demonstrate that the current surface‐modified polymer fibers can be used in tissue engineering applications, such as cell patterning substrates or vascular prosthesis development. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010.
PI3K is involved in L‐selectin‐ and PSGL‐1‐mediated neutrophil rolling on E‐selectin via F‐actin redistribution and assembly
Authors: Luo Jixian , Xu Tingshuang , Wang Xiaoguang , Ba Xueqing , Feng Xue , Deepak Vishwa , Zeng Xianlu
Published: April 2010

L‐selectin and P‐selectin glycoprotein ligand‐1 (PSGL‐1) are adhesion molecules that play critical roles in neutrophil rolling during inflammation and lymphocyte homing. On the other hand they also function as signaling receptors to induce cytoskeleton changes. The present study is to investigate the signaling kinases responsible for the F‐actin changes mediated by L‐selectin and PSGL‐1 during neutrophil rolling on E‐selectin. Western blot analysis demonstrated that PI3K activation, peaking within 5 min, was induced by ligation of L‐selectin and PSGL‐1 with E‐selectin, and that Vav1 (the pivotal downstream effector of PI3K signaling pathway involved in cytoskeleton regulation) was recruited to the membrane and tyrosine‐phosphorylated, depending on PI3K. Furthermore, the F‐actin redistribution and assembly mediated by ligation with E‐selectin were blocked by LY294002, a PI3K specific inhibitor. Additional experiments showed that PI3K activity was involved in neutrophil rolling on E‐selectin. However, Syk/Zap70, the well‐known upstream kinase of PI3K, was not involved in this event. These data suggest that PI3K is required for the F‐actin‐based cytoskeleton changes during neutrophil rolling on E‐selectin, which may consequently regulate the rolling event. J. Cell. Biochem. 110: 910–919, 2010. © 2010 Wiley‐Liss, Inc.
Polarizable empirical force field for sulfur‐containing compounds based on the classical Drude oscillator model
Authors: Zhu Xiao , Mackerell Alexander D.
Published: April 2010

Condensed‐phase computational studies of molecules using molecular mechanics approaches require the use of force fields to describe the energetics of the systems as a function of structure. The advantage of polarizable force fields over nonpolarizable (or additive) models lies in their ability to vary their electronic distribution as a function of the environment. Toward development of a polarizable force field for biological molecules, parameters for a series of sulfur‐containing molecules are presented. Parameter optimization was performed to reproduce quantum mechanical and experimental data for gas phase properties including geometries, conformational energies, vibrational spectra, and dipole moments as well as for condensed phase properties such as heats of vaporization, molecular volumes, and free energies of hydration. Compounds in the training set include methanethiol, ethanethiol, propanethiol, ethyl methyl sulfide, and dimethyl disulfide. The molecular volumes and heats of vaporization are in good accordance with experimental values, with the polarizable model performing better than the CHARMM22 nonpolarizable force field. Improvements with the polarizable model were also obtained for molecular dipole moments and in the treatment of intermolecular interactions as a function of orientation, in part due to the presence of lone pairs and anisotropic atomic polarizability on the sulfur atoms. Significant advantage of the polarizable model was reflected in calculation of the dielectric constants, a property that CHARMM22 systematically underestimates. The ability of this polarizable model to accurately describe a range of gas and condensed phase properties paves the way for more accurate simulation studies of sulfur‐containing molecules including cysteine and methionine residues in proteins. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2010
“Moved by the spirit”: does spirituality moderate the interrelationships between subjective well‐being subscales?
Authors: Schuurmans‐Stekhoven James
Published: April 2010

Despite the recent escalation of research into the spirituality and well‐being link, past efforts have been plagued by methodological problems. However, the potential for measurement error within psychometric instruments remains largely unexplored. After reviewing theory and evidence suggesting spirituality might represent an affective misattribution, moderation modeling—with each subjective well‐being (SWB) subscale as a dependent variable as predicted by the remaining SWB subscales—is utilized to test the assumption of scale invariance. These interrelationships were shown to vary in conjunction with spirituality; that is the analysis revealed significant spirituality × subscale interactions. Importantly, in all models the spirituality main effect was either nonsignificant or accounted for by other predictors. In combination, the findings suggest the interrelationship between the subscales rather than the level of SWB varies systematically with spirituality and casts considerable doubt on the previously reported “belief‐as‐benefit” effect. © 2010 Wiley Periodicals, Inc. J Clin Psychol: 66:1–17, 2010.
Structural changes in gonadal basement membranes during sex differentiation in the frog Rana rugosa
Authors: Saotome Kazuhiro , Isomura Tomoko , Seki Tatsunori , Nakamura Yoriko , Nakamura Masahisa
Published: April 2010

Here we report that structural changes in gonadal basement membranes during sex differentiation in the frog Rana rugosa are revealed using an antibody to its laminin component. Immunohistochemical staining indicated that the first sexual dimorphism appeared in testicular cords and ovarian cavities in differentiating gonads of tadpoles at St. 25‐3W, three weeks after they reached St. 25. During development, as the testis enlarged, testicular cord partitions appeared to form by invagination of the testicular epithelium. Ovarian cavities also increased in volume. Laminin‐positive basement membranes initially surrounded a partial surface of oocytes close to the ovarian cavity, fully covering growing oocytes by St. X. Laminin‐reactive signals were present in somatic cells outside seminiferous tubules in the testis and outside oocytes in one‐year‐old frogs. BrdU‐labeling showed that the number of dividing germ cells increased continuously in male gonads but increased in females only up to St. V, declining at St. X and thereafter. The number of dividing germ cells declined when the basement membranes had fully covered the oocytes. Together, these findings suggest that the first sexual dimorphism in the gonad of R. rugosa first appears as a structural change in the basement membranes. Finally, we speculate that the basement membrane on the surface of oocytes may affect their proliferation in this species. J. Exp. Zool. 313A:369–380, 2010. © 2010 Wiley‐Liss, Inc.
Ontogenesis of gonadal aromatase gene expression in atlantic silverside (Menidia menidia) Populations with genetic and temperature‐dependent sex determination
Authors: Duffy Tara A. , Picha Matthew E. , Won Eugene T. , Borski Russell J. , McElroy Anne E. , Conover David O.
Published: April 2010

Cytochrome P450 aromatase (P450arom), an enzyme that converts testosterone to 17β‐estradiol, is an important mediator of sex determination in teleosts with genetic sex determination (GSD) and temperature‐dependent sex determination (TSD). We compared the ontogenetic expression of P450arom in two populations of Atlantic silversides, Menidia menidia, which exhibit TSD (South Carolina) or GSD (Nova Scotia, Canada) using quantitative, real‐time polymerase chain reaction (qRT‐PCR). Embryos and newly hatched larvae were reared at an intermediate sex ratio‐producing temperature (21°C), and older larvae and juveniles were reared at temperatures that feminize (15°C) and masculinize (28°C) to assess the temperature response of P450arom during development. Before sex determination, embryos and newly‐hatched larvae displayed negligible P450arom expression, indicating minimal upregulation of this gene before sex determination. Gene expression increased in both populations during sex differentiation. Nova Scotia fish with GSD exhibited presumptive male‐ and female‐like expression levels during early sex differentiation that were not influenced by temperature. South Carolina fish displayed low levels of expression at 28oC with significantly heightened expression in some individuals at 15°C, indicating that P450arom is temperature sensitive in the population with TSD. Populations also differed in the timing and maximal levels of P450arom expression, with fish from Nova Scotia exhibiting both the highest and earliest increase in expression in presumptive females. Our results support the hypothesis that P450arom is involved in female sex differentiation in this species, but is only responsive to temperature in M. menidia populations that exhibit TSD. J. Exp. Zool. 313A:421–431, 2010. © 2010 Wiley‐Liss, Inc.
A detailed micro‐Raman spectroscopic study of wall paintings of the period AD 100–200: effect of atmospheric conditions on the alteration of samples
Authors: Cristini Odile , Kinowski Christophe , Turrell Sylvia
Published: April 2010

In this study, optical microscopy and micro‐Raman spectroscopy were used to determine the chemical compositions of the materials used in the preparatory and pictorial layers of wall paintings from four different sites of the Roman Empire of first to second century AD. The use of UV excitation for the Raman work for the study of the preparatory layers made it possible to overcome the problems of fluorescence. The fresco technique, revealed by the presence of calcite in the Greek and Roman samples, was not used for the Gallo–Roman works. The studies indicated that the same compounds were used for red and green pigments throughout the Roman Empire: red ocher (hematite) and green earths (celadonite, in the case of the Gallo–Roman fragments). It is shown that the impact of the atmosphere on the sample surface is very important, because the only fragments to have suffered identifiable deterioration are those from the ‘open‐air humid room’ in Kenchreai. The presence of gypsum in these samples in the absence of pigment indicates the implication of SO2 in the deterioration and makes it possible to suggest that the pigments in the pictorial layer can serve as a protection for the calcite preparatory layers. Copyright © 2010 John Wiley & Sons, Ltd.
XRP6258‐induced gene expression patterns in head and neck cancer carcinoma
Authors: Yoo George H. , Kafri Zyed , Ensley John F. , Lonardo Fulvio , Kim Harold , Folbe Adam J. , Won Joshua , Stevens Timothy , Lin Ho‐Sheng
Published: April 2010

Objectives/Hypothesis:

XRP6258 is a novel taxoid, which has antitumor activity in preclinical mouse orthotopic and human xenograft cancer models. However, limited XRP6258 studies have been performed in head and neck squamous cell carcinoma cells (HNSCC). The objective of this study is to identify the antitumor activity of XRP6258 in HNSCC cell line models.

Methods:

HNSCC cells (HN30 and HN12) were exposed to either XRP6258 or docetaxel. XRP6258‐induced growth suppression, cell cycle arrest and apoptosis were measured. Further, XRP6258‐induced expression patterns of selected genes were compared to docetaxel‐induced expression patterns using Western blot analysis.

Results:

XRP6258 suppressed proliferation and induced G2M arrest and apoptosis in both of the cell lines tested. XRP6258 and docetaxel produced similar alteration in the expression of cell cycle regulators, such as cyclin A and cyclin B1. The expression of E2F and EGFR were decreased in both XRP6258 and docetaxel‐treated HNSCC cells. Finally, XRP6258 induced a greater level of bcl2 phosphorylation than docetaxel in HN12 cell line.

Conclusions:

XRP6258 appeared to have a similar mechanism of action as docetaxel in the two HNSCC cell lines studied. XRP6258 induced cell cycle arrest, growth suppression, and apoptosis by altering gene expression patterns similar to that induced by docetaxel. These preclinical experiments suggest that XRP6258 may be useful in treating HNSCC, and the aforementioned genes can potentially be used as surrogate endpoint biomarkers. Laryngoscope, 120:1114–1119, 2010
Elective neck dissection during salvage surgery for locally recurrent head and neck squamous cell carcinoma after radiotherapy with elective nodal irradiation
Authors: Dagan Roi , Morris Christopher G. , Kirwan Jessica M. , Werning John W. , Vaysberg Mikhail , Amdur Robert J. , Mendenhall William M.
Published: April 2010

Objectives/Hypothesis:

To define the role of elective neck dissection during salvage surgery for locally recurrent head and neck squamous cell carcinoma (SCCA) initially treated with elective nodal irradiation (ENI).

Study Design:

Retrospective chart review.

Methods:

We reviewed the medical records of patients treated with ENI at our institution from 1965 to 2006 for T1‐4 N0 M0 SCCA of the oropharynx, hypopharynx, or larynx who developed an isolated local recurrence and remained N0. Fifty‐seven patients were salvaged, 40 with neck dissection and 17 with neck observation. We then compared toxicity and actuarial outcomes between the two groups. Results were compared to the pertinent literature in a pooled analysis.

Results:

Four of 46 (9%) heminecks were found to have occult metastases in dissected specimens. The 5‐year local‐regional control rate was 75% for all patients. Neck dissection resulted in poorer outcomes compared with observation. In the dissected group, the 5‐year local control, regional control, cause‐specific survival, and overall survival rates were 71%, 87%, 60%, and 45%, respectively, compared to 82%, 94%, 92%, and 56%, respectively, for the observed group. Toxicity was more likely with dissection. In the pooled analysis totaling 230 patients, the overall pathologic positive rate of neck‐dissection specimens was 9.6%; the compiled data showed no improvement in outcomes when salvage included neck dissection.

Conclusions:

Routine elective neck dissection should not be included during salvage surgery for locally recurrent head and neck SCCA if initial radiotherapy includes ENI. The risk of occult neck disease is low, outcomes do not improve, and the likelihood of toxicity increases. Laryngoscope, 2010
Increased expression of acidic mammalian chitinase and chitotriosidase in the nasal mucosa of patients with allergic rhinitis
Authors: Cho Woo Sung , Kim Tae Hoon , Lee Heung Man , Lee Seung Hoon , Lee Sung Ho , Yoo Joon Hyuk , Kim Yeon Soo , Lee Sang Hag
Published: April 2010

Objectives/Hypothesis:

Acidic mammalian chitinase (AMCase) has emerged as an important mediator of allergic asthma in both animal models and in humans. Recently, chitotriosidase has been suggested to play a role in innate immunity because of its phagocytic‐specific expression. Thus, AMCase and chitotriosidase may play a role in the pathogenesis of allergic nasal mucosa. The expression and pattern of distribution of AMCase and chitotriosidase were, therefore, determined in normal and allergic nasal mucosa.

Study Design:

Controlled, prospective study.

Methods:

Normal inferior turbinate mucosa was obtained in patients who were admitted for augmentation rhinoplasty. Allergic turbinate mucosa was obtained from patients who had perennial allergic rhinitis during septo‐turbinate surgery. Reverse transcriptase‐polymerase chain reaction (RT‐PCR), immunohistochemistry, and Western blotting were applied to the normal and allergic nasal mucosa.

Results:

The expression of AMCase and chitotriosidase mRNAs and proteins analyzed by RT‐PCR and Western blot were detected in all normal and allergic turbinate mucosa tested. The levels of expression of AMCase and chitotriosidase mRNAs and proteins were increased in allergic turbinate mucosa compared with normal turbinate mucosa. In both normal and allergic turbinate mucosa, AMCase and chitotriosidase were detected in the epithelium, inflammatory cells, and submucosal glands. The staining intensity for AMCase and chitotriosidase was stronger in allergic nasal mucosa than normal nasal mucosa.

Conclusions:

AMCase and chitotriosidase are constitutively expressed in normal turbinate mucosa, suggesting involvement in defense against chitin‐containing pathogens. Upregulation of these chitinases in allergic condition suggests that they may play a role in the nasal allergic reaction like other inflammatory mediators in allergic rhinitis. Laryngoscope, 2010
The bioflavonoid compound, sinupret, stimulates transepithelial chloride transport in vitro and in vivo
Authors: Virgin Frank , Zhang Shaoyan , Schuster Daniel , Azbell Christopher , Fortenberry James , Sorscher Eric J. , Woodworth Bradford A.
Published: April 2010

Objectives/Hypothesis:

Dehydration of airway surface liquid (ASL) disrupts normal mucociliary clearance in sinonasal epithelium leading to chronic rhinosinusitis. Abnormal chloride (Cl−) transport is one mechanism that contributes to this disorder, as demonstrated by the disease cystic fibrosis. Identifying safe compounds that stimulate transepithelial Cl− transport is critical to improving hydration of the ASL and promoting mucociliary transport. Sinupret (Bionorica, LLC, San Clemente, CA), a combination of naturally occurring bioflavonoids, is a widely used treatment for respiratory ailments in Europe. However, the effects of Sinupret on target respiratory epithelium have yet to be fully investigated. The present study evaluated the mechanisms underlying this bioflavonoid therapeutic on transepithelial Cl− transport in respiratory epithelium.

Study Design:

In vitro and in vivo investigation.

Methods:

Well characterized murine nasal septal epithelial (MNSE) cultures, and murine nasal potential difference (NPD) techniques were used to evaluate the effects of Sinupret on Cl− secretion.

Results:

The change in Sinupret‐stimulated current (Δ ISC expressed as μA/cm2) in MNSE, representing Cl− secretion, was significantly increased when compared to controls (19.04 ± 1.67 μA/cm2 vs. 1.8 ± 0.35 μA/cm2, respectively; P = .00005). Transepithelial Cl− transport measured in the murine NPD in vivo assay (n = 42) was also significantly enhanced when compared to controls (−0.8 mV vs. −0.9 mV; P = .0004). Importantly, Sinupret‐stimulated Cl− transport was substantially more robust in vivo than forskolin, a compound among the strongest known cystic fibrosis transmembrane conductance regulator activators (−3.8 mV vs. −1.65 mV; P = .01).

Conclusions:

Sinupret strongly activates transepithelial Cl− secretion through a mechanism known to hydrate the ASL of respiratory epithelium. This is one means by which the medication is likely to exert therapeutic benefit. Laryngoscope, 2010
Graph Kernels for Molecular Similarity
Authors: Rupp Matthias , Schneider Gisbert
Published: April 2010

Molecular similarity measures are important for many cheminformatics applications like ligand‐based virtual screening and quantitative structure‐property relationships. Graph kernels are formal similarity measures defined directly on graphs, such as the (annotated) molecular structure graph. Graph kernels are positive semi‐definite functions, i.e., they correspond to inner products. This property makes them suitable for use with kernel‐based machine learning algorithms such as support vector machines and Gaussian processes. We review the major types of kernels between graphs (based on random walks, subgraphs, and optimal assignments, respectively), and discuss their advantages, limitations, and successful applications in cheminformatics.
Vanadocene arsenate complexes: evidence of super‐hyperfine coupling with 75As
Authors: Honzíček Jan , Vinklárek Jaromír , Kratochvíl Pavel , Hrbáč Jan
Published: April 2010

The reaction of vanadocene dichloride with sodium arsenate gives Cp2V(O2AsO2H). This compound was identified on the basis of the super‐hyperfine coupling observed in the solution EPR spectrum. The effect of substitution was studied on the ring‐substituted and ansa‐bridged compounds. Copyright © 2010 John Wiley & Sons, Ltd.
Heterocyclic analogs of xanthiones: 5,6‐fused 3‐methyl‐1‐phenylpyrano[2,3‐c]pyrazol‐4(1H) thiones—synthesis and NMR (1H, 13C, 15N) data
Authors: Huemer Valerie , Eller Gernot A. , Holzer Wolfgang
Published: April 2010

Various [5,6]pyrano[2,3‐c]pyrazol‐4(1H)‐thiones were synthesized in high yields by treatment of the corresponding [5,6]pyrano[2,3‐c]pyrazol‐4(1H)‐ones with Lawesson's reagent. Detailed NMR spectroscopic studies were undertaken of the title compounds. Complete and unambiguous assignment of chemical shifts (1H, 13C, 15N) and coupling constants (1H,1H; 13C,1H) was achieved by the combined application of various one‐ and two‐dimensional (1D and 2D) NMR spectroscopic techniques. Unequivocal mapping of most 13C,1H spin coupling constants is accomplished by 2D (δ, J) long‐range INEPT spectra with selective excitation. Copyright © 2010 John Wiley & Sons, Ltd.
Manifestations of systemic sclerosis necessitate a holistic approach to patient care: a case report
Authors: Moots Robert J.
Published: April 2010

This case describes a young woman with manifestations of systemic sclerosis in multiple organ systems and her guidance through two successful pregnancies. This case emphasizes that patients with severe diseases are not just clinical cases; they each have unique needs and concerns beyond the physical manifestations of their disease. Young patients can be a particular challenge due to their need for independence. Communication is the key. Textbook advice in this case was that the risks posed by pregnancy were too great; however, a holistic approach, including frank discussion and much practical support, enabled the patient to make informed choices about her life, with a successful outcome. Copyright © 2010 John Wiley & Sons, Ltd.
Trägerfixierte Metallocene: Eine neue Katalysatorgeneration für die Polyolefin‐Produktion
Authors: Steinmetz Bernd , Zechlin Joachim , Przybyla Christian , Tesche Bernd , Fink Gerhard
Published: April 2010

Die seit Jahren intensiv untersuchten homogenen Metallocen–Katalysatoren für die Polyolefin‐Produktion weisen gegenüber den konventionellen Ziegler‐Systemen deutliche Vorteile bezüglich der Variationsmöglichkeiten der Mikrostruktur und damit der Eigenschaften der erzeugten Polymere auf. Sie müssen allerdings für den industriellen Einsatz auf Trägermaterialien immobilisiert werden. Welchen Einflüssen dabei Polymerisationskinetik, Polymerwachstum und Polymermorphologie sowie die entscheidende Partikelfragmentierung ausgesetzt sind, wird in diesem Beitrag geschildert und in einem Modell zusammengefaßt
Neue Techniken zum Gentransfer in Eukaryontenzellen
Authors: Weber Martin
Published: April 2010

Seit Millionen von Jahren optimieren Viren ihre Strategien zum Einbringen ihrer genetischen Information in eukaryontische Wirtszellen. Nur effiziente und immer wieder verbesserte Eindringmechanismen ermöglichten während dieser Zeit das “Überleben” der momentan existierenden Virusstämme als Zellparasiten. Um effiziente nichtvirale Vektoren zu entwickeln, orientiert sich die Gentechnik immer stärker an diesen Stratgien.
GABAA‐Rezeptorsubtyp‐Spezifität von Benzodiazepinen
Authors: Maelicke Alfred
Published: April 2010

Eine Punktmutation in der α1‐Untereinheit des GABAA‐Rezeptors bei Mäusen verhindert, dass die durch GABA induzierte Cl‐‐Kanalaktivität dieses Subtyp weiterhin durch klassische Benzodiazepine modulierbar ist: Mäuse, die mit dem mutierten Gen ausgestattet sind, zeigen nicht mehr die beruhigende und angstlösende Wirkung der Benzodiazepine. Die Wirkung dieser allosterischen Modulatoren ist daher Rezeptorsubtyp‐spezifisch, was die Hoffnung eröffnet, dass selektive Benzodiazepine entwickelt werden können.
ChemOffice Ultra 2000 Teil 1: ChemDraw und Add‐Ons
Authors: Ihlenfeldt Wolf–Dieter
Published: April 2010

Neben dem Klassiker ChemDraw vertreibt Cambridge Soft eine ganze Reihe weiterer Programme, vorwiegend gebündelt. Die neueste Ausgabe des ChemOffice‐Pakets enthält neben ChemDraw noch das Modellierungsprogramm Chem3D und die Datenbank ChemFinder; diese beiden Programme werden in der nächsten Ausgabe der „Nachrichten”︁ besprochen.
Chemiestandort Leuna ‐international und mittelständisch
Authors: Hauthal Hermann G.
Published: April 2010

Neben dem marktgerechten Ausbau traditioneller Produktlinien werden am Chemiestandort Leuna heute bereits viele neue Erzeugnisse vor allem der Spezialchemie hergestellt. Die modernste Raffinerie Europas, die Verfügbarkeit chemischer Grundstoffe und technischer Gase, eine leistungsfähige, hochmoderne Infrastruktur und der interessante Mix aus internationalen Großunternehmen und mittelständischen Firmen bieten beste Voraussetzungen für die Ansiedlung neuer Investoren.
Modelling the flow of self‐compacting concrete
Authors: Kulasegaram S. , Karihaloo B. L. , Ghanbari A.
Published: April 2010

A Lagrangian particle‐based method, smooth particle hydrodynamics (SPH), is used in this paper to model the flow of self‐compacting concretes (SCC) with or without short steel fibres. An incompressible SPH method is presented to simulate the flow of such non‐Newtonian fluids whose behaviour is described by a Bingham‐type model, in which the kink in the shear stress vs shear strain rate diagram is first appropriately smoothed out. The viscosity of the SCC is predicted from the measured viscosity of the paste using micromechanical models in which the second phase aggregates are treated as rigid spheres and the short steel fibres as slender rigid bodies. The basic equations solved in the SPH are the incompressible mass conservation and Navier–Stokes equations. The solution procedure uses prediction–correction fractional steps with the temporal velocity field integrated forward in time without enforcing incompressibility in the prediction step. The resulting temporal velocity field is then implicitly projected on to a divergence‐free space to satisfy incompressibility through a pressure Poisson equation derived from an approximate pressure projection. The results of the numerical simulation are benchmarked against actual slump tests carried out in the laboratory. The numerical results are in excellent agreement with test results, thus demonstrating the capability of SPH and a proper rheological model to predict SCC flow and mould‐filling behaviour. Copyright © 2010 John Wiley & Sons, Ltd.
Cell to node projections: An assessment of error
Authors: Goumiri Imene R. , Prevost Jean H.
Published: April 2010

Reservoir simulators typically use cell‐centered finite volume schemes and do not model directly the coupling of the flow processes with the geomechanics. Coupling of geomechanics with fluid flow can be important in many cases, but introducing fully coupled geomechanical effects in those simulators is not a trivial issue, because the geomechanics is better done by using the Galerkin vertex‐centered finite element methods by which the solid displacements are computed at the vertices of the cells. This creates difficulties in interfacing cell variables with nodal variables. Uncoupled or loosely coupled models are used by many researchers/practitioners by which a reservoir model is coupled to a geomechanical model by staggering in‐time flow and deformation via a sophisticated interface that repeatedly calls first flow and then mechanics. The method therefore requires projection of the reservoir cell variables onto the nodes of the geomechanics Galerkin finite element mesh.

In this note, we attempt to quantify the errors associated with cell to node projection operations. For that purpose, we use a simple model of the pressure equation for a heterogeneous medium in one dimension. We are able to derive theexactanalytical solution for this problem for both nodal and cell pressures. This allows us to compute the errors due to projection analytically, function of meshing refinement and permeability field variations. We compute upper and lower bounds for the errors, and analyze their magnitude for a variety of cases. We conclude that, in general, cell to node projection operations lead to substantial errors. Copyright © 2010 John Wiley & Sons, Ltd.
Animal models and their use in understanding lower urinary tract dysfunction
Authors: Fry C.H. , Daneshgari F. , Thor K. , Drake M. , Eccles R. , Kanai A.J. , Birder L.A.
Published: April 2010

This review will highlight appropriate animal models for the study of a number of disorders involving changes to lower urinary tract function. A major hurdle to the development of animal models for human lower urinary tract disorders is that the clinical pathophysiology of the latter mostly remain idiopathic. Acute injury/inflammation of otherwise healthy animals has often been used to study effects on a target tissue/organ. However, these “acute” models may not adequately address the characteristics of “chronic” visceral disorders. In addition, the relevance of observed changes following acute injury/inflammation, in terms of possible therapeutic targets, may not reflect that which occurs in the human condition. We have therefore emphasized the situations when animal models are required to investigate lower urinary tract disorders and what they should set out to achieve. In particular we have discussed the merits and disadvantages of a number of paradigms that set out to investigate specific lower urinary tract disorders or situations associated with these conditions. These include animal models of overactive bladder, stress urinary incontinence, ageing and congenital defects of the urinary tract and bladder pain syndrome. Neurourol. Urodynam. 29:603–608, 2010. Copyright © 2010 Wiley‐Liss, Inc.
Female pelvic surgical devices and techniques need better evidence‐based medicine
Authors: Staskin David , Khullar Vik
Published: April 2010

The adoption of evidence‐based medicine (EBM) recommendations in female pelvic surgical technique and surgical device intervention is contingent upon the availability of EBM and the willingness and ability of practitioners to accept and implement the recommendations. It can be assumed that there is virtually no disagreement among either the practitioners or the experts who practice the craft with regard to the benefits of applying scientific and clinical data that can be obtained from prior and ongoing experience to the selection of current treatments. However, there is significant controversy regarding the existence of adequate “evidence” and the mechanism for developing and applying the recommendations that can be distilled from the available data. Neurourol. Urodynam. 29:670–675, 2010. © 2010 Wiley‐Liss, Inc.
A new fast hybrid adaptive grid generation technique for arbitrary two‐dimensional domains
Authors: Ebeida Mohamed S. , Davis Roger L. , Freund Roland W.
Published: April 2010

This paper describes a new fast hybrid adaptive grid generation technique for arbitrary two‐dimensional domains. This technique is based on a Cartesian background grid with square elements and quadtree decomposition. A new algorithm is introduced for the distribution of boundary points based on the curvature of the domain boundaries. The quadtree decomposition is governed either by the distribution of the boundary points or by a size function when a solution‐based adaptive grid is desired. The resulting grid is quaddominant and ready for the application of finite element, multi‐grid, or line‐relaxation methods. All the internal angles in the final grid have a lower bound of 45° and an upper bound of 135°. Although our main interest is in grid generation for unsteady flow simulations, the technique presented in this paper can be employed in many other fields. Several application examples are provided to illustrate the main features of this new approach. Copyright © 2010 John Wiley & Sons, Ltd.
Differential diagnosis of an unusual tibial pathology from Peru
Authors: Phillips S. S. , Verano J. W.
Published: April 2010

During an osteological analysis of human skeletal remains from the site of Punta Lobos (Huarmey Valley, northern coastal Peru), an unusual erosive lesion of the cortex with periosteal reaction was observed on a right tibia. The authors undertook a review of paleopathological and medical literature to arrive at a differential diagnosis. The lesion is determined to be a non‐malignant growth, possibly a large periosteal ganglion, though a diagnosis of periosteal chondroma (a benign neoplasm) or other uncommon neoplasm could not be definitively ruled out. Copyright © 2010 John Wiley & Sons, Ltd.
Phase I study of bortezomib combined with chemotherapy in children with relapsed childhood acute lymphoblastic leukemia (ALL): A report from the therapeutic advances in childhood leukemia (TACL) consortium
Authors: Messinger Yoav , Gaynon Paul , Raetz Elizabeth , Hutchinson Raymond , DuBois Steven , Glade‐Bender Julia , Sposto Richard , van der Giessen Jeannette , Eckroth Elena , Bostrom Bruce C.
Published: April 2010

Background

Outcomes remain poor for children after relapse of acute lymphoblastic leukemia (ALL), especially after early marrow relapse. Bortezomib is a proteasome inhibitor with in vitro synergy with corticosteroids and clinical activity in human lymphoid malignancies.

Procedure

This is a Phase I study of escalating doses bortezomib administered days 1, 4, 8, and 11, added to 4‐drug induction chemotherapy with vincristine, dexamethasone, pegylated L‐asparaginase, and doxorubicin (VXLD) in children with relapsed ALL.

Results

Ten patients were enrolled, five in first marrow relapse, and five in second relapse. Four patients were enrolled at dose level 1 (bortezomib 1 mg/m2). One patient was not evaluable for toxicity because of omitted dexamethasone doses. No dose‐limiting toxicity (DLT) was observed. Six patients were enrolled at dose level 2 (bortezomib 1.3 mg/m2). One patient had dose‐limiting hypophosphatemia and rhabdomyolysis after 1 dose of bortezomib, and died from a diffuse zygomyces infection on day 17. Five additional patients were enrolled with no subsequent DLTs. As planned, no further dose escalation was pursued. The regimen had predictable toxicity related to the chemotherapy drugs. Two patients had mild peripheral neuropathy (grades 1 and 2). Six of nine evaluable patients (67%) achieved a complete response (CR), and one had a bone marrow CR with persistent central nervous system leukemia.

Conclusions

The combination of bortezomib (1.3 mg/m2) with VXLD is active with acceptable toxicity in pretreated pediatric patients with relapsed ALL. We are expanding the 1.3 mg/m2 cohort for a phase II estimate of response. Study registered at ClinicalTrials.gov (http://clinicaltrials.gov/ct2/show/NCT00440726). Pediatr Blood Cancer 2010;55:254–259. © 2010 Wiley‐Liss, Inc.
WT1 peptide immunotherapy for cancer in children and young adults
Authors: Hashii Yoshiko , Sato Emiko , Ohta Hideaki , Oka Yoshihiro , Sugiyama Haruo , Ozono Keiichi
Published: April 2010

Wilms tumor gene (WT1) can be overexpressed in childhood cancers. We evaluated the efficacy of WT1 vaccination for five children with solid cancer or acute leukemia. WT1 vaccine was administered to HLA‐A*2402‐positive patients with WT1‐overexpressing residual tumor despite prior conventional treatment. One patient showed complete response and one patient showed stable disease according to the Response Evaluation Criteria in Solid Tumors; the remaining three showed progressive disease. Treatment‐related adverse effects were limited to local injection site erythema. These results suggest that WT1 vaccination has therapeutic potential, but any beneficial effect may be insufficient in the presence of gross residual disease. Pediatr Blood Cancer. 2010;55:352–355. © 2010 Wiley–Liss, Inc.
Cyclic neutropenia and severe congenital neutropenia in patients with a shared ELANE mutation and paternal haplotype: Evidence for phenotype determination by modifying genes
Authors: Newburger Peter E. , Pindyck Talia N. , Zhu Zhiqing , Bolyard Audrey Anna , Aprikyan Andrew A.G. , Dale David C. , Smith Gary D. , Boxer Laurence A.
Published: April 2010

Background

Cyclic neutropenia (CN) and severe congenital neutropenia (SCN) are disorders of neutrophil production that differ markedly in disease severity. Mutations of the ELANE gene (the symbol recently replacing ELA2) are considered largely responsible for most cases of CN and SCN, but specific mutations are typically associated with one or the other.

Procedure

We performed ELANE genotyping on all individuals and paternal sperm in an SCN kindred with eight SCN progeny of a sperm donor and six different mothers.

Results

One patient with CN had the same S97L ELANE mutation as seven patients with the SCN phenotype. The mutant allele was detected in the donor's spermatozoa, representing 18% of the ELANE gene pool, but not in DNA from his lymphocytes, neutrophils, or buccal mucosa, indicating gonadal mosaicism.

Conclusions

The coexistence of CN and SCN phenotypes in this kindred with a shared paternal haplotype strongly suggests both a role for modifying genes in determination of congenital neutropenia disease phenotypes, and the classification of CN and SCN within a spectrum of phenotypes expressing varying degrees of the same disease process. Pediatr Blood Cancer. 2010;55:314–317. © 2010 Wiley–Liss, Inc.
Quantum catalysis? A comment on tunnelling contributions for catalysed and uncatalysed reactions
Authors: Williams Ian H.
Published: April 2010

Appreciation for the contribution of nuclear quantum effects (NQEs) to chemical reactivity predates transition‐state theory (TST). Quantum corrections to rate constants for the reactions catalysed by lactate dehydrogenase (LDH) and formate dehydrogenase (FDH) and the same reactions in water are estimated by Bell's one‐dimensional approximate method and give tunnelling contributions to catalysis of 1.6 and 0.95, respectively. Published results for NQEs, including both tunnelling and zero‐point energies, estimated by the quantum classical path method for LDH, carbonic anhydrase, glyoxylase I and lipoxygenase, together with the corresponding reactions in water, are reviewed: the respective contributions to catalysis are 0.66, 5, 1 and 1. In the absence of better evidence that an enzymic rate enhancement is due to a significantly larger quantum correction for the enzyme‐catalysed reaction than for an appropriate uncatalysed reference reaction, it is suggested that the term ‘quantum catalysis’ should be used with caution and restraint. Copyright © 2010 John Wiley & Sons, Ltd.
Simulated glass transition in free‐standing thin polystyrene films
Authors: Baljon A. R. C. , Williams S. , Balabaev N. K. , Paans F. , Hudzinskyy D. , Lyulin A. V.
Published: April 2010

In this article, we investigate the glass transition in polystyrene melts and free‐standing ultra‐thin films by means of large‐scale computer simulations. The transition temperatures are obtained from static (density) and dynamic (diffusion and orientational relaxation) measurements. As it turns out, the glass transition temperature of a 3 nm thin film is ∼60 °K lower than that of the bulk. Local orientational mobility of the phenyl bonds is studied with the help of Legendre polynomials of the second‐order P2(t). The α and β relaxation times are obtained from the spectral density of P2(t). Our simulations reveal that interfaces affect α and β‐relaxation processes differently. The β relaxation rate is faster in the center of the film than near a free surface; for the α relaxation rate, an opposite trend is observed. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1160–1167, 2010
Viscosity of sodium carboxymethylcellulose in ethylene glycol–water mixed solvent media: Separation of the influences of polyion conformation and electrostatic interactions on the reduced viscosity
Authors: Sharma Ramesh , Das Bijan , Nandi Prabir , Das Chanchal
Published: April 2010

Precise measurements on the viscosities of the solutions of sodium carboxymethylcellulose in water and three ethylene glycol–water mixtures containing 10, 20, and 30 mass % of ethylene glycol have been reported at 35 °C. Isoionic dilutions were performed at total ionic strengths in the range of 0.0002–0.0008 eqv L−1 using sodium chloride to obtain the intrinsic viscosities along with the Huggins constants. The influence of the medium and the ionic strength on the intrinsic viscosities have been interpreted from the points of view of the counterion condensation and expansion/contraction of the polyion chains in solution. The variations of Huggins constants, on the other hand, provided information on the intermolecular interactions in these solutions. A convenient method has been proposed to decompose the reduced viscosity of a polyelectrolyte solution into its conformational and electrostatic components. The electrostatic reduced viscosities obtained in the present study, purely from experimental considerations, quantitatively corroborates the conclusions derived from the Huggins constants. Using the Hess and Klein theoretical approach, an expression for the reduced viscosity due to the electrostatic interactions as a function of polyelectrolyte concentration could be obtained and the reported experimental electrostatic contributions could be nicely described with the help of this approach. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1196–1202, 2010
Complementary effects of multiwalled carbon nanotubes and conductive carbon black on polyamide 6
Authors: Cheng Henry Kuo Feng , Sahoo Nanda Gopal , Pan Yongzheng , Li Lin , Chan Siew Hwa , Zhao Jianhong , Chen Ge
Published: April 2010

This article introduces a newly innovative idea for preparation of superconductive ternary polymeric composites of polyamide 6 (PA6), conductive carbon black (CCB), and multiwalled carbon nanotubes (MWCNTs) with different weight ratios by a melt‐mixing technique. The complementary effects of CCB and MWCNTs at different compositions on rheological, physical, morphological, thermal, and dynamic mechanical and electrical properties of the ternary composites have been examined systematically. We have used a novel formulation to produce high‐weight fraction ternary polymer composites that show extremely higher conductivity when compared with their corresponding binary polymer composites at the same carbon loading. For example, with an addition of 10 wt % MWCNTs into the CCB/PA6 composite preloaded with 10 wt % CCB, the electrical conductivity of these ternary composites was about 5 S/m, which was 10 times that of the CCB/PA6 binary composite (0.5 S/m) and 125 times that of the MWCNT/PA6 binary composite (0.04 S/m) at 20 wt % carbon loading. The incorporation of the MWCNTs effectively enhanced the thermal stability and crystallization of the PA6 matrix in the CCB/PA6 composites through heterogeneous nucleation. The MWCNTs appeared to significantly affect the mechanical and rheological properties of the PA6 in the CCB/PA6 composites, a way notably dependent on the MWCNT contents. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 48: 1203–1212, 2010