bluuebunny/crossref_metadata_2025 huggingface dataset:
False-positive inferior petrosal sinus sampling in the diagnosis of Cushing's disease
Authors: Yamamoto Yoshihiro , Davis Dudley H. , Nippoldt Todd B. , Young William F. , Huston John , Parisi Joseph E.
Published: June 2009

✓ Inferior petrosal sinus sampling (IPSS) for adrenocorticotropic hormone (ACTH) levels in patients with Cushing's syndrome has become a useful method to distinguish ACTH-secreting pituitary tumors (Cushing's disease) from other causes of the syndrome, principally ectopic adrenocorticotropin secretion by an occult tumor. Although the test is generally regarded as highly specific, the authors recently encountered two patients whose IPSS measurements were false-positive for Cushing's disease. The results of IPSS suggested a pituitary origin of ACTH secretion in both patients, but transsphenoidal surgery failed to disclose a pituitary adenoma or to improve postoperative plasma cortisol levels. Both patients subsequently were found to have an ACTH-secreting carcinoid tumor of the lung. The false-positive IPSS studies were due to periodic hormonogenesis. The patients must be hypercortisolemic at the time IPSS is performed for the study to be valid.
Ectopic pituitary adenoma occurring in the interpeduncular cistern
Authors: Takahata Tetsuya , Katayama Yoichi , Tsubokawa Takashi , Oshima Hideki , Yoshino Atsuo
Published: June 2009

✓ Intracranial ectopic pituitary adenoma occurs most frequently in the suprasellar cistern, usually in continuity with the pituitary stalk. Such tumors probably originate from cells of the pars tuberalis located above the diaphragma sellae or from aberrant anterior pituitary cells of the pituitary stalk. The authors report the case of a 37-year-old woman with Cushing's syndrome caused by an ectopic pituitary adenoma of unique location: the tumor was separate from the pituitary stalk and confined within the interpeduncular cistern. After surgical removal of the tumor, continued improvement in the patient's laboratory results and disappearance of her endocrine symptoms strongly indicated the absence of adenoma cells in the pituitary gland or stalk. The tumor in the present case appears to have arisen from aberrant pituitary cells that were present in the leptomeninges of the basal surface of the hypothalamus.
Cannulated screws for odontoid screw fixation and atlantoaxial transarticular screw fixation
Authors: Dickman Curtis A. , Foley Kevin T. , Sonntag Volker K. H. , Smith Maurice M.
Published: June 2009

✓ Cannulated screw systems use thin Kirschner wires (K-wires) that have been drilled into the bone to direct screw trajectories accurately into small bone fragments. Use of the K-wires avoids overdrilling the pilot holes and allows fixation of adjacent bone fragments during screw insertion. Hollow tools and hollow screws are inserted into the bone over the K-wires. Cannulated screw fixation is useful in the cervical spine to stabilize odontoid fractures and to treat atlantoaxial instability. This report describes techniques for successful cannulated screw insertion and methods to minimize complications. Cannulated screws have several distinct advantages compared to noncannulated screws: 1) the K-wires guide the screw position into the bone; 2) the K-wire trajectory can be repositioned easily if the original trajectory was not ideal; 3) the K-wires allow continuous fixation of adjacent unstable bone fragments; and 4) the K-wires prevent migration of unstable bone fragments during screw insertion.

Complications associated with the K-wire (breakage, repositioning, and advancement) can be minimized using precise operative techniques, a specialized tool system, and intraoperative fluoroscopic monitoring. A unique cannulated screw tool system was developed specifically for upper cervical fixation to allow percutaneous drilling using long tunneling devices, tissue sheaths, drill guides, and long K-wires. These tools allow delivery of cannulated fracture-fixation screws at a low angle to the spine through long soft-tissue trajectories. Cannulated screws have significant advantages compared to noncannulated screws for fixation of the unstable cervical spine.
Design and Fabrication of a MEMS Flow Sensor and Its Application in Precise Liquid Dispensing
Authors: Liu Yaxin , Chen Liguo , Sun Lining
Published: June 2009

A high speed MEMS flow sensor to enhance the reliability and accuracy of a liquid dispensing system is proposed. Benefitting from the sensor information feedback, the system can self-adjust the open time of the solenoid valve to accurately dispense desired volumes of reagent without any pre-calibration. First, an integrated high-speed liquid flow sensor based on the measurement of the pressure difference across a flow channel is presented. Dimensions of the micro-flow channel and two pressure sensors have been appropriately designed to meet the static and dynamic requirements of the liquid dispensing system. Experiments results show that the full scale (FS) flow measurement ranges up to 80 μL/s, with a nonlinearity better than 0.51% FS. Secondly, a novel closed-loop control strategy is proposed to calculate the valve open time in each dispensing cycle, which makes the system immune to liquid viscosity, pressure fluctuation, and other sources of error. Finally, dispensing results show that the system can achieve better dispensing performance, and the coefficient of variance (CV) for liquid dispensing is below 3% at 1 μL and below 4% at 100 nL.
Health-related Quality of Life and Its Relationship to Patient Disease Course in Childhood-onset Systemic Lupus Erythematosus
Authors: BRUNNER HERMINE I. , HIGGINS GLORIA C. , WIERS KRISTINA , LAPIDUS SIVIA K. , OLSON JUDYANN C. , ONEL KAREN , PUNARO MARILYNN , YING JUN , KLEIN-GITELMAN MARISA S. , SEID MICHAEL
Published: June 2009

Objective.

To (1) estimate the health-related quality of life (HRQOL) of children with childhood-onset systemic lupus erythematosus (cSLE) and compare it to that of normative cohorts; (2) assess the relationship of HRQOL with cSLE disease activity and damage; and (3) determine the effects of changes of disease activity on HRQOL.

Methods.

Patients with cSLE (n = 98) followed every 3 months completed HRQOL measures, the Pediatric Quality of Life Inventory Generic Core scale (PedsQL-GC), the Rheumatology Module (PedsQL-RM), and the Child Health Questionnaire (CHQ). The British Isles Lupus Activity Group Index (BILAG) was used to measure organ-system-specific disease activity. Physicians rated the course of cSLE between visits.

Results.

At baseline, mean (standard deviation, SD) score [parent report] of the PedsQL-GC and the PedsQL-RM was 75 (17) and 79 (14), respectively; the mean (SD) of the CHQ physical summary score (CHQ-PHS) was 49 (7) and that of the CHQ psychological summary score was 42 (12). Higher BILAG scores, especially in the general, musculoskeletal, neurological, and vascular, but not the mucocutaneous, renal, cardiovascular, or hematological BILAG domains, were associated with a significantly lower HRQOL. Patients with damage had lower HRQOL than those without damage. All HRQOL measures included were at most modestly responsive to clinically important changes with cSLE.

Conclusion.

HRQOL with cSLE is significantly lower than that reported in healthy populations. Organ-specific involvement with cSLE has a differential effect on HRQOL. Higher disease activity and damage are associated with significantly lower HRQOL as measured by the PedsQL-RM and the CHQ-PHS, and worsening of cSLE leads to a further decline.
Pattern of Joint Involvement and Other Disease Characteristics in 634 Patients with Arthritis of Less Than 16 Weeks’ Duration
Authors: MJAAVATTEN MARIA DAHL , HAUGEN ANNE JULSRUD , HELGETVEIT KNUT , NYGAARD HALVOR , SIDENVALL GÖRAN , UHLIG TILL , KVIEN TORE KRISTIAN
Published: June 2009

Objective.

To investigate the distribution of joint involvement in a cohort of patients with very recent onset arthritis and describe the disease characteristics in these patients.

Methods.

A very early arthritis clinic (NOR-VEAC) was established as a multicenter study. General practitioners were asked to refer patients presenting with at least 1 swollen joint of maximum 16 weeks’ duration. Clinical and laboratory markers were examined.

Results.

We included 634 patients during the first 3 years, with mean (25th–75th percentile) arthritis duration of 30 (11–63) days. Monoarthritis was present in 243 (38.3%) patients, 216 (34.1%) had oligoarthritis, and 175 (27.6%) polyarthritis. Patients with polyarthritis were older, had longer duration of arthritis, and were more frequently anti-cyclic citrullinated peptide antibody and rheumatoid factor-positive. Patients in all 3 joint pattern groups (mono-/oligo-/polyarthritis) reported substantial effect on physical function, pain, and fatigue and had elevated levels of acute-phase reactants. Knee or ankle arthritis was most frequent in patients with mono- and oligoarthritis, whereas small joint involvement was most frequent in patients with polyarthritis.

Conclusion.

Patients with recent-onset arthritis report a substantial influence on health status. Mono- and oligoarthritis are at least as frequent as polyarthritis. Polyarthritic patients more frequently exhibit features associated with a worse outcome.
Hollow Micro/Nanomaterials with Multilevel Interior Structures
Authors: Zhao Yong , Jiang Lei
Published: June 2009

In this Review, recent achievements in the multilevel interior‐structured hollow 0D and 1D micro/nanomaterials are presented and categorized. The 0D multilevel interior‐structured micro/nanomaterials are classified into four main interior structural categories that include a macroporous structure, a core‐in‐hollow‐shell structure, a multishell structure, and a multichamber structure. Correspondingly, 1D tubular micro/nanomaterials are of four analogous structures, which are a segmented structure, a wire‐in‐tube structure, a multiwalled structure, and a multichannel structure. Because of the small sizes and complex interior structures, some special synthetic strategies that are different from routine hollowing methods, are proposed to produce these interior structures. Compared with the same‐sized solid or common hollow counterparts, these fantastic multilevel hollow‐structured micro/nanomaterials show a good wealth of outstanding properties that enable them broad applications in catalysis, sensors, Li‐ion batteries, microreactors, biomedicines, and many others.
Die Entwicklung von Substrattopographien im Mikro‐ und Nanobereich zur Steuerung von Zellfunktionen
Authors: Bettinger Christopher J. , Langer Robert , Borenstein Jeffrey T.
Published: June 2009

Die Wechselwirkung von Säugerzellen mit der nanoskaligen Topographie einer Unterlage hat sich als wichtiges Signalelement zur Steuerung der Zellfunktion herausgestellt. Natürliche nanotopographische Strukturen in der extrazellulären Matrix präsentieren den umgebenden Zellen mechanotransduktive Signale, die die lokale Migration, die Zellpolarisation und andere Funktionen beeinflussen. Auch eine synthetische Nanotopographie kann sich auf Zellmorphologie, Ausrichtung, Adhäsion, Migration, Proliferation und Organisation des Cytoskeletts auswirken. Im Folgenden stellen wir dar, wie sich der Kontakt zwischen Zellen und Substraten mit synthetischer Nanotopographie nutzen lässt, um komplexe zelluläre Prozesse wie Stammzelldifferenzierung und Gewebeorganisation in vitro zu steuern. Weitere Herausforderungen an der Schnittstelle zwischen Zelle und nanotopographischen Oberflächen werden diskutiert, darunter die Aufklärung von Mechanismen und Anwendungen im Tissue‐Engineering.
Synthesis and Reactivity of a Strained Silicon‐Bridged [1]Ferrocenophanium Ion
Authors: Masson Georgeta , Herbert David E. , Whittell George R. , Holland Jason P. , Lough Alan J. , Green Jennifer C. , Manners Ian
Published: June 2009

Rotbraun statt blau: Ein [1]Ferrocenophanium‐Ion wurde synthetisiert und in Form eines kristallinen Salzes isoliert, dessen rotbraune Farbe vom charakteristischen Blaugrün nichtgespannter Ferrocenium‐Ionen abweicht. Im [1]Ferrocenophanium‐Ion sind die Ringe deutlich stärker gegeneinander verkippt als in der neutralen Eisen(II)‐Verbindung, und es neigt daher stärker zur Ringöffnung.

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Engineering Substrate Topography at the Micro‐ and Nanoscale to Control Cell Function
Authors: Bettinger Christopher J. , Langer Robert , Borenstein Jeffrey T.
Published: June 2009

The interaction of mammalian cells with nanoscale topography has proven to be an important signaling modality in controlling cell function. Naturally occurring nanotopographic structures within the extracellular matrix present surrounding cells with mechanotransductive cues that influence local migration, cell polarization, and other functions. Synthetically nanofabricated topography can also influence cell morphology, alignment, adhesion, migration, proliferation, and cytoskeleton organization. We review the use of in vitro synthetic cell–nanotopography interactions to control cell behavior and influence complex cellular processes, including stem‐cell differentiation and tissue organization. Future challenges and opportunities in cell–nanotopography engineering are also discussed, including the elucidation of mechanisms and applications in tissue engineering.
Growth Mechanism of Metal–Organic Frameworks: Insights into the Nucleation by Employing a Step‐by‐Step Route
Authors: Shekhah Osama , Wang Hui , Zacher Denise , Fischer Roland A. , Wöll Christof
Published: June 2009

One step at a time: The in situ monitoring of the step‐by‐step formation of metal–organic frameworks (MOFs) by using surface plasmon resonance (SPR), allows the nucleation process and the formation of the secondary building units to be investigated. Growth rates on functionalized organic surfaces with different crystallographic orientations can also be studied.

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Luminescent Terbium Protein Labels for Time‐Resolved Microscopy and Screening
Authors: Rajapakse Harsha E. , Reddy D. Rajasekhar , Mohandessi Shabnam , Butlin Nathaniel G. , Miller Lawrence W.
Published: June 2009

Brilliance of terbium: Heterodimeric conjugates of trimethoprim covalently linked to sensitized terbium chelates bind to Escherichia coli dihydrofolate reductase fusion proteins with nanomolar affinity (see picture). Terbium luminescence enables sensitive and time‐resolved detection of labeled proteins in vitro and on the surface of living mammalian cells.

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Melt electrospinning of low‐density polyethylene having a low‐melt flow index
Authors: Deng Rongjian , Liu Yong , Ding Yumei , Xie Pengcheng , Luo Lu , Yang Weimin
Published: June 2009

Melt electrospinning is a cheaper, more environmentally friendly, and safer alternative to solution electrospinning. We have designed a novel melt spinning device which incorporates a reverse of the normal polarity, with the capillary grounded and the collector grid at positive potential. The apparatus is much simpler and more economical than conventional equipment because no syringe pump is required. Low‐density polyethylene (LDPE) with a low‐melt flow index of 2 g/10 min, which is not suitable for spinning using current commercial methods, was chosen to highlight the advantages of melt electrospinning in general, and our device in particular. The effects of varying the electrospinning parameters such as temperature, electrostatic field, spinning distance, and capillary inner diameter, have been studied. Although it was found that temperatures higher than normal processing temperatures had to be employed in our electrospinning system to reduce the viscosity of the polymer melt sufficiently, good quality fibers with smooth and even surfaces, most of which had diameters smaller than 15 μm, were electrospun successfully. It was observed that there was an optimum point for the spinning distance (14–15 cm) and the capillary inner diameter (0.4–0.6 mm) to get fine fiber. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Aged Human Thymus Hassall's Corpuscles Are Immunoreactive for IGF‐I and IGF‐I Receptor
Authors: Marinova Tsvetana Ts. , Spassov Lyubomir D. , Vlassov Veselin I. , Pashev Vili V. , Markova Maya D. , Ganev Varban S. , Dzhupanova Ralitsa S. , Angelov Doychin N.
Published: June 2009

Although Hassall's corpuscles have been proposed to act in both maturation of developing thymocytes and removal of apoptotic cells, their function remains an enigma. The involvement of insulin‐like growth factor I (IGF‐I) in the local autocrine and paracrine control of T‐cell development in human thymus is still unclear. In this study, we investigated the structure and distribution of IGF‐I and IGF‐I receptor (IGF‐IR)‐immunopositive Hassall's corpuscles in aged human thymus using bright‐field immunohistochemistry and immunoelectron microscopy. We report new immunocytochemical data for the presence of IGF‐I/IGF‐IR double‐immunopositive Hassall's corpuscles in structurally preserved regions of age‐involuted thymus and discuss the involvement of these unique thymic components in the local regulation of T‐cell development and thymus plasticity during aging by IGF‐I/IGF‐IR‐mediated cell signaling pathway. Anat Rec., 2009. © 2009 Wiley‐Liss, Inc.
Verformungsvorhersage von vorgespannten und nicht vorgespannten Betonbauteilen
Authors: Krüger Wolfgang , Mertzsch Olaf , Koch Steffen
Published: June 2009

Wie vergleichende Untersuchungen zeigen, führt eine Begrenzung der Verformung auf der Grundlage des Schlankheitsnachweises, wie er nach DIN 1045‐1 bei Stahlbetonbauteilen möglich ist, nicht immer zu dem gewünschten Erfolg. In diesen Fällen und bei Spannbetonkonstruktionen ist grundsätzlich ein Nachweis der Verformungen erforderlich.

Ausgehend von allgemeinen Betrachtungen zum Nachweis der Bauteilverformungen, werden wesentliche materialseitige Einflüsse auf die Verformungsvorhersage diskutiert. Es wird deutlich, dass eine genaue Berechnung der Verformung nur bedingt möglich ist.

Im Anschluss wird für die tägliche Berechnungspraxis ein Näherungsansatz zur Vorhersage der Verformung bewehrter Betonbauteile formuliert. Im Rahmen von vergleichenden Betrachtungen wird die Genauigkeit des entwickelten Näherungsansatzes abgeschätzt. Hierbei zeigt sich eine gute baupraktische Übereinstimmung zwischen komplexen Berechnungen und dem vereinfachten Berechnungsansatz.
From heavy metal‐binders to biosensors: Ciliate metallothioneins discussed
Authors: Gutiérrez Juan C. , Amaro Francisco , Martín‐González Ana
Published: June 2009

Metallothioneins (MTs) are ubiquitous proteins with the capacity to bind heavy metal ions (mainly Cd, Zn or Cu), and they have been found in animals, plants, eukaryotic and prokaryotic micro‐organisms. We have carried out a comparative analysis of ciliate MTs (Tetrahymena species) to well‐known MTs from other organisms, discussing their exclusive features, such as the presence of aromatic amino acid residues and almost exclusive cysteine clusters (CCC) present in cadmium‐binding metallothioneins (CdMTs), higher heavy metal‐MT stoichiometry values, and a strictly conserved modular–submodular structure. Based on this last feature and an extensive gene duplication, we propose a possible model for the evolutionary history of T. thermophila MTs. We also suggest possible functions for these MTs from consideration of their differential gene expressions and discuss the potential use of these proteins and/or their gene promoters for designing molecular or whole‐cell biosensors for a fast detection of heavy metals in diverse polluted ecosystems.
3‐D analysis of the Plasmodium falciparum Maurer's clefts using different electron tomographic approaches
Authors: Henrich Philipp , Kilian Nicole , Lanzer Michael , Cyrklaff Marek
Published: June 2009

The human malaria parasite Plasmodium falciparum exports a large number of proteins into its host erythrocyte to install functions necessary for parasite survival. Important structural components of the export machinery are membrane profiles of parasite origin, termed Maurer's clefts. These profiles span much of the distance between the parasite and the host cell periphery and are believed to deliver P. falciparum‐encoded proteins to the erythrocyte plasma membrane. Although discovered more than a century ago, Maurer's clefts remain a mysterious organelle with little information available regarding their origin, their morphology or their precise role in protein trafficking. Here, we evaluated different techniques to prepare samples for electron tomography, including whole cell cryo‐preparations, vitreous sections, freeze‐substitution and chemical fixation. Our data show that the different approaches tested all have their merits, revealing different aspects of the complex structure of the Maurer's clefts.
Anatomic evaluation of maxillary sinus septa: Surgery and radiology
Authors: Koymen Ramazan , Gocmen‐Mas Nuket , Karacayli Umit , Ortakoglu Kerim , Ozen Tuncer , Yazici Ayse Canan
Published: May 2009

The anatomical structure of the maxillary sinus is fundamental to maxillofacial surgery. The presence of septa, located at the inner surface of the maxillary sinus, increases the risk of sinus membrane perforation during sinus elevation for dental implant surgery. The aim of this study was to evaluate the anatomy of maxillary sinus septa.Data in this study was obtained from a total of 205 cases. One hundred and seventy‐seven patients were partially edentulous (PE) whereas 28 patients had no teeth. Dental computerized tomography (dental CT) was used in the assessment of 410 sinus segments (205 left and 205 right segments). The prevalence of sinus segments with septa was found to be 145/410. Septa were detected in 91 of the 177 PE cases. There were a total of 26 septa in 18 of the 28 completely edentulous (CE) cases. A total of 165 septa were detected in these segments. The prevalence of septa was 46.4% (26/56) in the CE, and 39.2% (139/354) in the PE segments. Thirty septa were found in the anterior, 110 in the middle and 25 in the posterior region. All detected septa were located mediolateral direction. Their relative position: lateral, middle or medial were also noted. The height measurements of the septa varied amongst the different positions. In view of the fact that septa of various heights and courses can develop in all parts of the maxillary sinus, timely and adequate assessment of the inner aspect of the maxillary sinus is essential to avoid complications during sinus augmentation procedures. Clin. Anat. 22:563–570, 2009. © 2009 Wiley‐Liss, Inc.
Development of a Method for the High‐Throughput Quantification of Cellular Proteins
Authors: Paganetti Paolo , Weiss Andreas , Trapp Monique , Hammerl Ina , Bleckmann Dorothée , Bodner Ruth A. , Coven‐Easter Shanie , Housman David E. , Parker Christian N.
Published: June 2009

Hunting for huntingtin: We describe a screening assay based on the inducible expression of the mutant huntingtin protein in cells and on its highly sensitive homogenous determination. Rapid, reproducible, and robust protein determination was achieved through the use of two donor–acceptor‐labeled antibodies and time‐resolved FRET. The assay was developed and validated for ultra‐throughput screening of low‐molecular‐weight compounds modulating the expression of the mutant protein.

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The quantification of cellular proteins is essential for the study of many different biological processes. This study describes an assay for the detection of the intracellular mutant huntingtin, the causative agent of Huntington's disease, with a method that may be generally applicable to other cellular proteins. A small recombinant protein tag that is recognized by a pair of readily available, high‐affinity monoclonal antibodies was designed. This tag was then added to an inducible fragment of the mutant huntingtin protein by genetic engineering. We show that it is possible to use time‐resolved FRET to detect low intracellular levels of huntingtin by a simple lysis and detection procedure. This assay was then adapted into a homogeneous, miniaturized format suitable for screening in 1536‐well plates. The use of time‐resolved FRET also permits the assay to be multiplexed with a standard readout of cell toxicity, thus allowing the identification of conditions causing reduction of protein levels simply due to cytotoxicity. The screening results demonstrated that the assay is able to identify compounds that modulate the levels of huntingtin both positively and negatively and that represent valuable starting points for drug discovery programs.
Small‐Molecule Targeting of the Mitochondrial Compartment with an Endogenously Cleaved Reversible Tag
Authors: Ripcke Jens , Zarse Kim , Ristow Michael , Birringer Marc
Published: June 2009

Reversible mitochondrial shuttle: A novel concept in mitochondrial pharmacology allows the transport of bioactive compounds into the mitochondrial compartment and their subsequent release. A lipoic acid derivative containing a cleavable (“reversible”) triphenylphosphonium tag is endogenously cleaved by the mitochondrial aldehyde dehydrogenase (ALDH‐2) after mitochondrial accumulation.

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Targeted accumulation of chemically unaltered compounds within the mitochondrial compartment has not yet been achieved. Here we describe a reversible tag that is endogenously cleaved after mitochondrial accumulation has occurred. Specifically, we have reversibly tagged α‐lipoic acid with a triphenylphosphonium moiety that is cleaved by the physiologically contained mitochondrial aldehyde dehydrogenase (ALDH‐2). This reversibly tagged compound activates the lipoic acidsensitive pyruvate dehydrogenase complex, and this results in increased glucose oxidation. We observed a reduction in ROS accumulation after preincubation with the reversibly tagged compound, whereas untagged or irreversibly tagged compounds either had no effect on ROS formation or rather caused increased oxidative stress, respectively. Lastly, the cytotoxicity of the reversibly tagged compound is less than that of the irreversibly tagged compound. Overall, reversible tagging combines decreased tag‐related cytotoxicity with increased bioactivity, and this potentially provides a novel concept in mitochondrial pharmacology.
Borate‐Driven Gatelike Scaffolding Using Mesoporous Materials Functionalised with Saccharides
Authors: Aznar Elena , Coll Carmen , Marcos M. Dolores , Martínez‐Máñez Ramón , Sancenón Félix , Soto Juan , Amorós Pedro , Cano Joan , Ruiz Eliseo
Published: June 2009

We report the development of an MCM‐41 mesoporous support that is functionalised with saccharides at the pore outlets and contains the dye [Ru(bipy)3]2+ in the pores (solid S1; bipy=2,2′‐bipyridyl). For this hybrid system, the inhibition of mass transport of the dye from the pore voids to the bulk solution in the presence of borate is demonstrated in water at neutral pH. The formation of the corresponding boroester derivative is related to the selective reaction of borate with the appended saccharides. This control is selective and only anion borate, among several anions and cations, can act as a molecular tap and inhibit the delivery of the entrapped guest. Additionally, the S1–borate system behaves as pH‐controlled gatelike scaffolding. This pH‐responsive release can be achieved in an acidic pH (due to hydrolysis of the boroester), whereas the system remains closed at neutral pH. Molecular dynamic simulations using force‐field methods have been made to theoretically study the open/close borate‐driven mechanism. A mesoporous silica structure was constructed for this purpose, taking the plane (1−11) of the β‐cristobalite structure as a base on which hexagonal nanopores and anchored saccharide derivatives were included. The final model shows a highly flexible nanopore diameter of approximately 12.5 Å of similar size to the [Ru(bipy)3]2+ complex (ca. 12 Å). However, the anchoring of borate to the appended saccharides results in a remarkable reduction of the pore size (down to ca. 6.4 Å) and a significant constraint in the flexibility and mobility of the saccharides. The theoretical calculations are in agreement with the experimental results and enable visualisation of the functional borate‐driven dye‐delivery‐inhibition outcome.
The Central Atom Size Effect on the Structure of Group 14 Tetratolyls
Authors: Ng Maggie C. C. , Craig Donald J. , Harper Jason B. , van‐Eijck Lambert , Stride John A.
Published: June 2009

Size matters! The structure and dynamics of the tetratolyl Group 14 elements, which were probed by using high‐resolution inelastic neutron scattering spectra, show a remarkable dependence on the size of the central atom. The para‐methyl groups at the periphery of the molecules constitute the frontier intermolecular interactions of increasingly larger tetrahedra, which becomes critical at the molecular radius of the Si and Ge analogues (see picture).

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Bifunctional Catalysis by Natural Cinchona Alkaloids: A Mechanism Explained
Authors: Cucinotta Clotilde S. , Kosa Monica , Melchiorre Paolo , Cavalli Andrea , Gervasio Francesco L.
Published: June 2009

The use of bifunctional chiral catalysts, which are able to simultaneously bind and activate two reacting partners, currently represents an efficient and reliable strategy for the stereoselective preparation of valuable chiral compounds. Cinchona alkaloids such as quinine and quinidine, simple organic molecules generously provided by Nature, were the first compounds to be proposed to operate through a cooperative catalysis. To date, a full mechanistic characterization of the dual catalysis mode of cinchona alkaloids has proven a challenging objective, due to the transient, non‐covalent nature of the involved catalyst–substrate interactions. Here, we propose a mechanistic rationale on how natural cinchona alkaloids act as efficient bifunctional catalysts by using a broad range of computational methods, including classical molecular dynamics, a mixed quantum mechanical/molecular mechanics (QM/MM) approach, and correlated ab‐initio calculations. We also unravel the origin of enantio‐ and diastereoselectivity, which is due to a specific network of hydrogen bonds that stabilize the transition state of the rate‐determining step. The results are validated by experimental evidence.
Activity‐based restorative therapies: Concepts and applications in spinal cord injury‐related neurorehabilitation
Authors: Sadowsky Cristina L. , McDonald John W.
Published: June 2009

Physical rehabilitation following spinal cord injury‐related paralysis has traditionally focused on teaching compensatory techniques, thus enabling the individual to achieve day‐to‐day function despite significant neurological deficits. But the concept of an irreparable central nervous system (CNS) is slowly being replaced with evidence related to CNS plasticity, repair, and regeneration, all related to persistently maintaining appropriate levels of neurological activity both below and above the area where the damage occurred. It is now possible to envision functional repair of the nervous system by implementing rehabilitative interventions. Making the transition from “bench to bedside” requires careful analysis of existing basic science evidence, strategic focus of clinical research, and pragmatic implementation of new therapeutic tools. Activity, defined as both function specific motor task and exercise appears to be a necessity for optimization of functional, metabolic, and neurological status in chronic paralysis. Crafting a comprehensive rehabilitative intervention focused on functional improvement through neurological gains seems logical. The terms activity‐based restorative therapies, activity‐based therapies, and activity‐based rehabilitation have been coined in the last 10 years to describe a new fundamental approach to deficits induced by neurological paralysis. The goal of this approach is to achieve activation of the neurological levels located both above and below the injury level using rehabilitation therapies. This article reviews basic and clinical science evidence pertaining to implementation of physical activity and exercise as a therapeutic tool in the management of chronic spinal cord‐related neurological paralysis. © 2009 Wiley‐Liss, Inc. Dev Disabil Res Rev 2009;15:112–116.
Kurzbericht über die 63. Sitzung des Technischen Lenkungsausschusses der EOTA (EOTA Technical Board) am 5. Februar 2009 in Brüssel
Authors: Sterling Andrea
Published: June 2009

Bis Anfang Februar 2009 erteilten die derzeit insgesamt 45 Zulassungsstellen der EOTA über 1350 europäische technische Zulassungen (European Technical Approvals – ETAs). Mehr als 40 % der gültigen ETAs sind Zulassungen des Deutschen Instituts für Bautechnik (DIBt).

Als Grundlage für die Erteilung von ETAs stehen 27 Leitlinien zur Verfügung, die größtenteils in der deutschen Fassung beim DIBt bestellt werden können und alternativ in der englischen Fassung auf der EOTA‐Internetseite verfügbar sind. Zunehmend werden europäische technische Zulassungen ohne Leitlinie gemäß Art. 9 Abs. 2 der Bauproduktenrichtlinie erteilt. Derzeit liegen dafür insgesamt 125 spezielle, in EOTA abgestimmte Beurteilungsgrundlagen vor (60 davon erstellt vom bzw. unter Mitarbeit des DIBt).

In den letzten Monaten wurden von den Diensten der Europäischen Kommission zahlreiche der von EOTA beantragten Produktbereiche für die Erteilung von ETAs ohne Leitlinie freigegeben. Derzeit befinden sich in EOTA 140 Beurteilungsgrundlagen in Bearbeitung und/oder Abstimmung, wobei der Entwurf für eine Beurteilungsgrundlage von der EOTA‐Stelle erarbeitet wird, bei der ein ETA‐Antrag für den betreffenden Produktbereich vorliegt. Das DIBt erarbeitet derzeit Entwürfe für 41 Beurteilungsgrundlagen bzw. ist an deren Erarbeitung beteiligt.
Shaking table test on small‐scale retrofitted model of Sefid‐rud concrete buttress dam
Authors: Ghaemmaghami A. R. , Ghaemian M.
Published: June 2009

Sefid‐rud concrete buttress dam with a height of 106 m was damaged during the devastating 1990 Manjil earthquake. The dam was repaired and strengthened using epoxy grouting of cracks and the installation of post‐tensioned anchors.

In a previous study, nonlinear seismic response of the highest monolith with empty reservoir was investigated experimentally through model testing. A geometric‐scaled model of 1:30 was tested on a shaking table to study dynamic cracking of the model. As a result of the similarity between model and prototype cracking pattern, the model was retrofitted according to prototype retrofitting plan after the Manjil earthquake and re‐tested on shaking table to estimate the current safety of the prototype.

Experimental test results showed that the post‐tensioning resulted in a significant decrease in dynamic responses in terms of crest displacement and measured strains of the retrofitted model in comparison with its corresponding responses at the first test. No cracking was observed in the retrofitted model when the base motion peak acceleration exceeded a value that was 22% higher than the one caused cracking in the first model. This can be interpreted as the efficiency of prototype post‐tensioning system in evaluating the seismic safety of Sefid‐rud dam. Copyright © 2009 John Wiley & Sons, Ltd.
Temporal variation in soil detachment under different land uses in the Loess Plateau of China
Authors: Zhang Guang‐hui , Tang Ming‐ke , Zhang X. C.
Published: June 2009

Measurements of temporal variations in soil detachability under different land uses are badly needed to develop new algorithms or evaluate the existing ones for temporal adjustment of soil detachability in continuous soil erosion models. Few studies have been conducted in the Loess Plateau to quantify temporal variations in detachment rate of runoff under different land uses. The objectives of this study were to investigate the temporal variations of soil detachment rate under different land uses and to further identify the potential factors causing the change in detachment rate in the Loess Plateau. Undisturbed soil samples were collected in the fields of arable land (millet, soybean, corn, and potato), grassland, shrub land, wasteland, and woodland and tested in a laboratory flume under a constant hydraulic condition. The measurements started in mid‐April and ended in early October, 2006. The results showed that soil detachment rate of each land use fluctuated considerably over time. Distinctive temporal variation in detachment rate was found throughout the summer growing season of measurement in each land use. The maximum detachment rates of different land uses varied from 0·019 to 0·490 kg m–2 s–1 and the minimum detachment rates ranged from 0·004 to 0·092 kg m–2 s–1. Statistical analysis using a paired‐samples t‐test indicated that variations in soil detachment rate differed significantly at the 0·05 level between land uses in most cases. The major factors responsible for the temporal variation of soil detachment were tillage operations (such as planting, ploughing, weeding, harvesting), soil consolidation, and root growth. The influence of tillage operations on soil detachment depended on the degree of soil disturbance caused by the operations. The consolidation of the topsoil over time after tillage was reflected by increases in soil bulk density and soil cohesion. As soil bulk density and cohesion increased, detachment rate decreased. The impact of root density was inconclusive in this study. Further studies are needed to quantify the effects of root density on temporal variations of soil detachment. This work provides useful information for developing temporal adjustments to soil detachment rate in continuous soil erosion models in the Loess Plateau. Copyright © 2009 John Wiley & Sons, Ltd.
Performance bounds on BER of OFDMA with pulse shaping and maximal ratio combining diversity
Authors: Le Khoa N.
Published: June 2009

This letter derives bounds on the bit error rate (BER) of orthogonal frequency division multiple access (OFDMA) systems employing Lth‐order diversity and pulse shaping in Rayleigh fading environments. First, a new probability density function (pdf) of the signal‐to‐interference ratio (SIR) per bit γk in the presence of inter‐carrier interference power PICI and multiple access interference PMAI is derived. The pdf of the sum of square of the multi‐path gain αk is obtained. Second, the BER of OFDMA systems with binary phase shift keying (BPSK) modulation employing maximal ratio combining (MRC) diversity is derived using the SIR pdf. Detailed discussions are given below. Copyright © 2009 John Wiley & Sons, Ltd.
Numerical simulation of free‐surface flow using the level‐set method with global mass correction
Authors: Zhang Yali , Zou Qingping , Greaves Deborah
Published: June 2009

A new numerical method that couples the incompressible Navier–Stokes equations with the global mass correction level‐set method for simulating fluid problems with free surfaces and interfaces is presented in this paper. The finite volume method is used to discretize Navier–Stokes equations with the two‐step projection method on a staggered Cartesian grid. The free‐surface flow problem is solved on a fixed grid in which the free surface is captured by the zero level set. Mass conservation is improved significantly by applying a global mass correction scheme, in a novel combination with third‐order essentially non‐oscillatory schemes and a five stage Runge–Kutta method, to accomplish advection and re‐distancing of the level‐set function. The coupled solver is applied to simulate interface change and flow field in four benchmark test cases: (1) shear flow; (2) dam break; (3) travelling and reflection of solitary wave and (4) solitary wave over a submerged object. The computational results are in excellent agreement with theoretical predictions, experimental data and previous numerical simulations using a RANS‐VOF method. The simulations reveal some interesting free‐surface phenomena such as the free‐surface vortices, air entrapment and wave deformation over a submerged object. Copyright © 2009 John Wiley & Sons, Ltd.
Application of the observational method in geotechnical safety management
Authors: Moritz Bernd , Schubert Wulf
Published: June 2009

The uncertainties in the ground model and the subsequent design of tunnels call for an observational approach. To enable the safe and economical tunnelling of underground infrastructure projects with shallow overburden, a safety management plan has to be implemented. The successful application of the observational method is based on a comprehensive definition of the expected behaviour by the designer and the verification of the actual conditions by the site geotechnical engineer during construction. Advanced tools and methods for monitoring data evaluation assist in the continuous interpretation of the system behaviour, enable timely detection of deviations and check against the warning and alarm criteria. The paper shows the application of the observational method as defined in Eurocode7 as part of a Safety Management Plan through two case histories from OeBB tunnel projects.
Multiple pathways in the FGF signaling network are frequently deregulated by gene amplification in oral dysplasias
Authors: Tsui Ivy F.L. , Poh Catherine F. , Garnis Cathie , Rosin Miriam P. , Zhang Lewei , Lam Wan L.
Published: June 2009

Genetic alteration in oral premalignant lesions (OPLs), the precursors of oral squamous cell carcinomas (OSCCs), may represent key changes in disease initiation and development. We ask if DNA amplification occurs at this early stage of cancer development and which oncogenic pathways are disrupted in OPLs. Here, we evaluated 50 high‐grade dysplasias and low‐grade dysplasias that later progressed to cancer for gene dosage aberrations using tiling‐path DNA microarrays. Early occurrences of DNA amplification and homozygous deletion were frequently detected, with 40% (20/50) of these early lesions exhibiting such features. Expression for 88 genes in 7 recurrent amplicons were evaluated in 5 independent head and neck cancer datasets, with 40 candidates found to be overexpressed relative to normal tissues. These genes were significantly enriched in the canonical ERK/MAPK, FGF, p53, PTEN and PI3K/AKT signaling pathways (p = 8.95 × 10−3 to 3.18 × 10−2). These identified pathways share interactions in one signaling network, and amplification‐mediated deregulation of this network was found in 30.0% of these preinvasive lesions. No such alterations were found in 14 low‐grade dysplasias that did not progress, whereas 43.5% (10/23) of OSCCs were found to have altered genes within the pathways with DNA amplification. Multitarget FISH showed that amplification of EGFR and CCND1 can coexist in single cells of an oral dysplasia, suggesting the dependence on multiple oncogenes for OPL progression. Taken together, these findings identify a critical biological network that is frequently disrupted in high‐risk OPLs, with different specific genes disrupted in different individuals. © 2009 UICC
CXCR7 is inducible by HTLV‐1 Tax and promotes growth and survival of HTLV‐1‐infected T cells
Authors: Jin Zhe , Nagakubo Daisuke , Shirakawa Aiko‐Konno , Nakayama Takashi , Shigeta Akiko , Hieshima Kunio , Yamada Yasuaki , Yoshie Osamu
Published: June 2009

Human T‐lymphotropic virus type 1 (HTLV‐1), the etiological agent of adult T‐cell leukemia (ATL), encodes the potent transcriptional activator Tax, which is required for HTLV‐1‐induced immortalization of T cells. CXCR7 is an atypical chemokine receptor frequently expressed by tumor cells and known to promote cell growth and survival. We found that HTLV‐1‐immortalized T cells expressing Tax consistently expressed CXCR7. Induction of Tax in JPX‐9 upregulated CXCR7. Wild‐type Tax efficiently activated the CXCR7 promoter via a proximal NF‐κB site, while a mutant Tax selectively defective in NF‐κB activation did not. CCX754, a synthetic CXCR7 antagonist, inhibited cell growth and increased apoptosis of HTLV‐1‐immortalized T cells. Knockdown of CXCR7 by small interfering RNA also reduced cell growth. Stable expression of CXCR7 in a CXCR7‐negative ATL cell line promoted cell growth and survival. Taken together, CXCR7 is inducible by Tax and may play an important role in HTLV‐1‐induced immortalization of T cells by promoting growth and survival of HTLV‐1‐infected T cells. © 2009 UICC
Contextualizing Asian American education through critical race theory: An example of U.S. Pilipino college student experiences
Authors: Buenavista Tracy Lachica , Jayakumar Uma M. , Misa‐Escalante Kimberly
Published: June 2009

Critical race theory can be an important tool for developing a deeper understanding of the experiences of specific Asian American ethnic groups and individuals.
Construction of a multi‐functional extracellular matrix protein that increases number of N1E‐115 neuroblast cells having neurites
Authors: Nakamura Makiko , Mie Masayasu , Mihara Hisakazu , Nakamura Makoto , Kobatake Eiry
Published: June 2009

An artificially designed fusion protein, which was designed to have strong cell adhesive activity and an active functional unit that enhances neuronal differentiation of mouse N1E‐115 neuroblast cells, was developed. In this study, a laminin‐1‐derived IKVAV sequence, which stimulates neurite outgrowth in conditions of serum deprivation, was engineered and incorporated into an elastin‐derived structural unit. The designed fusion protein also had a cell‐adhesive RGD sequence derived from fibronectin. The resultant fusion protein could adsorb efficiently onto hydrophobic culture surfaces and showed cell adhesion activity similar to laminin. N1E‐115 cells grown on the fusion protein exhibited more cells with neurites than cells grown on laminin‐1. These results indicated that the constructed protein could retain properties of incorporated functional peptides and could provide effective signal transport. The strategy of designing multi‐functional fusion proteins has the possibility for supporting current tissue engineering techniques. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Study of the proinflammatory role of human differentiated omental adipocytes
Authors: Bassols Judit , Ortega Francisco J. , Moreno‐Navarrete José M. , Peral Belén , Ricart Wifredo , Fernández‐Real Jose‐Manuel
Published: June 2009

Infiltration of monocyte‐derived macrophages into adipose tissue has been associated with tissue and systemic inflammation. It has been suggested that macrophage infiltration affects fat expansion through a paracrine action on adipocyte differentiation. Our working hypothesis is that factors released by monocytes/macrophages may also affect mature adipocyte biology. Human differentiated omental adipocytes were incubated with LPS and conditioned media obtained from human macrophage‐like cell line THP‐1, previously activated or not with LPS. We show that LPS greatly increased the secretion levels of pro‐inflammatory adipokines including IL‐6, IL‐8, GRO, and MCP‐1. Macrophage‐conditioned medium also upregulated IL‐6, IL‐8, GRO, and MCP‐1 mRNA expression and protein levels and led to the novo secretion of ICAM‐1, IL‐1β, IP‐10, MIP‐1α, MIP‐1β, VEGF, and TNFα. Human differentiated adipocytes treated by macrophage‐conditioned medium displayed marked reduction of adipocyte function as assessed by decreased phosphorylation levels of ERK1, ERK2, and p38α and reduced gene expression of lipogenic markers including PPAR‐γ and fatty acid synthase. These data show that macrophage‐secreted factors not only inhibit the formation of mature adipocytes but alter their function, suggesting that human differentiated omental adipocytes might also contribute to systemic chronic low‐grade inflammation associated with human obesity. J. Cell. Biochem. 107: 1107–1117, 2009. © 2009 Wiley‐Liss, Inc.