bluuebunny/crossref_metadata_2025_split huggingface dataset:
Renal Intratubular Crystals and Hyaluronan Staining Occur in Stone Formers with Bypass Surgery but not with Idiopathic Calcium Oxalate Stones
Authors: Evan Andrew P. , Coe Fredric L. , Gillen Daniel , Lingeman James E. , Bledsoe Sharon , Worcester Elaine M. 
Published: February 2008

AbstractWhether idiopathic calcium oxalate (CaOx) stone formers form inner medullary collecting duct (IMCD) crystal deposits bears on pathogenetic mechanisms of stone formation. In prior work, using light and transmission electron microscopy, we have found no IMCD crystal deposits. Here, we searched serial sections of papillary biopsies from a prior study of 15 idiopathic calcium oxalate stone formers, 4 intestinal bypass patients with CaOx stones, and 4 non–stone‐forming subjects, and biopsies from an additional hitherto unreported 15 idiopathic calcium oxalate stone formers and 1 bypass patient using polarized light oil immersion optics, for deposits overlooked in our original study. We found no IMCD deposits in any of 1,500 serial sections from the 30 idiopathic calcium oxalate stone formers, nor in 87 additional sections from a frozen idiopathic calcium oxalate stone former biopsy sample processed without exposure to aqueous solutions. Among 4 of the 5 bypass patients but in none of the 30 idiopathic calcium oxalate stone formers or 4 normal stone formers, we found tiny birefringent thin crystalline overlays on scattered IMCD cell membranes. We also found IMCD lumen deposits in two bypass patients that contained mixed birefringent and nonbirefringent crystals, presumably CaOx and apatite. In the bypass patients, we observed focal apical IMCD cell hyaluronan staining, which was absent in idiopathic calcium oxalate stone formers. The absence of any IMCD deposits in 1,500 serial sections of biopsies from 30 idiopathic calcium oxalate stone formers allows us to place the upper limit on the probability of their occurrence at approximately 0.002 and place the lower limit of their size at the resolution of the optics (<0.2 μ). The tiny deposits in bypass patients may be the initial crystal lesion. Anat Rec, 291:325–334, 2008. © 2008 Wiley‐Liss, Inc.
Optimization of Volumetric Computed Tomography for Skeletal Analysis of Model Genetic Organisms
Authors: Vasquez Sergio X. , Hansen Mark S. , Bahadur Ali N. , Hockin Matthew F. , Kindlmann Gordon L. , Nevell Lisa , Wu Isabel Q. , Grunwald David J. , Weinstein David M. , Jones Greg M. , Johnson Christopher R. , Vandeberg John L. , Capecchi Mario R. , Keller Charles 
Published: February 2008

AbstractForward and reverse genetics now allow researchers to understand embryonic and postnatal gene function in a broad range of species. Although some genetic mutations cause obvious morphological change, other mutations can be more subtle and, without adequate observation and quantification, might be overlooked. For the increasing number of genetic model organisms examined by the growing field of phenomics, standardized but sensitive methods for quantitative analysis need to be incorporated into routine practice to effectively acquire and analyze ever‐increasing quantities of phenotypic data. In this study, we present platform‐independent parameters for the use of microscopic x‐ray computed tomography (microCT) for phenotyping species‐specific skeletal morphology of a variety of different genetic model organisms. We show that microCT is suitable for phenotypic characterization for prenatal and postnatal specimens across multiple species. Anat Rec, 291:475–487, 2008. © 2008 Wiley‐Liss, Inc.
Comparative Cellular Morphology Suggesting the Existence of Resident Dendritic Cells Within Immune Organs of Salmonids
Authors: Lovy Jan , Wright Glenda M. , Speare David J. 
Published: February 2008

AbstractThis report is the first morphological description of cells that resemble dendritic cells, which appear to form resident populations within the spleen and anterior kidney of fish. Based on examination of three salmonid species, including, rainbow trout, brook trout, and Atlantic salmon, the cells were most abundant in the spleen, although they were always present in the anterior kidney. The cells appeared diffusely distributed, often near blood vessels of the spleen and kidney of healthy fish and within the epithelium, connective tissue, and blood vessels of rainbow trout gills with experimentally induced microsoporidial gill disease. The dendritic‐like cells in this study contained granules that resemble Birbeck granules, which are considered to be morphological markers of Langerhans cells in mammals. The cells were approximately 6 μm in diameter and contained Birbeck‐like (BL) granules localized near centrioles. Although the dendritic‐like cells in the three salmonid species shared many similarities, morphological differences were found in the fine structure of the rod portion of the BL granules. Rainbow trout BL granules contained amorphous material, while the other salmonid species contained particulate material arranged in a square‐lattice arrangement. The BL granules in the cells of Atlantic salmon had a narrow diameter and contained four layers of particulate material when sectioned longitudinally; two layers enveloped by the granule membrane and two central layers making up a central lamella, which is common in mammalian Birbeck granules. Anat Rec, 291:456–462, 2008. © 2008 Wiley‐Liss, Inc.
Stability of Alkali Metal Halide Polymorphs as a Function of Pressure
Authors: Čančarević Željko P. , Schön J. Christian , Jansen Martin 
Published: February 2008

AbstractWe investigated the regions of thermodynamic stability of possible modifications of the alkali metal halides as a function of pressure and type of alkali metal and halogen. Both Hartree–Fock and density functional calculations (for six different functionals) were performed. The results are in good agreement with experiment, and the trends in the computed quantities such as transition pressures and lattice parameters as a function of the ab initio method are similar to those found in earlier studies of the alkali metal sulfides. We predict that in most of these systems the so‐called 5–5 modification should be metastable at standard pressure and be thermodynamically stable at slightly negative pressures. The sizes of the pressure ranges over which the various modifications are stable showed characteristic trends as a function of the type of the constituent elements, thus generalizing the traditional pressure–homologue rule for transition pressures and stable phases in ionic solids.
Hydrogen‐Bond‐Mediated Asymmetric Catalysis
Authors: Yu Xinhong , Wang Wei 
Published: February 2008

AbstractThe utilization of hydrogen bonding as an activation force has become a powerful tool in asymmetric organocatalysis. Significant advances have been made in the recent past in this emerging field. Due to space constraints, this Focus Review summarizes only the key aspects with an emphasis on catalysis based on chiral ureas and thioureas, diols, and phosphoric acids. The examples provided neatly demonstrate that chiral ureas and thioureas, diols, and phosphoric acids display effective and unique activation modes of catalysis for a broad spectrum of asymmetric organic transformations, including single‐step and multiple‐step cascade reactions. These functionalities, which have the ability to afford efficient H‐bond activation of electrophiles including CO, CN, aziridines, and epoxides, have established their status as “privileged” functional groups in the design of organocatalysts.
Mobile phone electromagnetic radiation activates MAPK signaling and regulates viability in Drosophila
Authors: Lee Kyu‐Sun , Choi Jong‐Soon , Hong Sae‐Yong , Son Tae‐Ho , Yu Kweon 
Published: February 2008

AbstractMobile phones are widely used in the modern world. However, biological effects of electromagnetic radiation produced by mobile phones are largely unknown. In this report, we show biological effects of the mobile phone 835 MHz electromagnetic field (EMF) in the Drosophila model system. When flies were exposed to the specific absorption rate (SAR) 1.6 W/kg, which is the proposed exposure limit by the American National Standards Institute (ANSI), more than 90% of the flies were viable even after the 30 h exposure. However, in the SAR 4.0 W/kg strong EMF exposure, viability dropped from the 12 h exposure. These EMF exposures triggered stress response and increased the production of reactive oxygen species. The EMF exposures also activated extracellular signal regulated kinase (ERK) and c‐Jun N‐terminal kinase (JNK) signaling, but not p38 kinase signaling. Interestingly, SAR 1.6 W/kg activated mainly ERK signaling and expression of an anti‐apoptotic gene, whereas SAR 4.0 W/kg strongly activated JNK signaling and expression of apoptotic genes. In addition, SAR 4.0 W/kg amplified the number of apoptotic cells in the fly brain. These findings demonstrate that the exposure limit on electromagnetic radiation proposed by ANSI triggered ERK‐survival signaling but the strong electromagnetic radiation activated JNK‐apoptotic signaling in Drosophila. Bioelectromagnetics 29:371–379, 2008. © 2008 Wiley‐Liss, Inc.
A new view of protein synthesis: Mapping the free energy landscape of the ribosome using single‐molecule FRET
Authors: Munro James B. , Vaiana Andrea , Sanbonmatsu Kevin Y. , Blanchard Scott C. 
Published: February 2008

AbstractThis article reviews the application of single‐molecule fluorescence resonance energy transfer (smFRET) methods to the study of protein synthesis catalyzed by the ribosome. smFRET is a powerful new technique that can be used to investigate dynamic processes within enzymes spanning many orders of magnitude. The application of wide‐field smFRET imaging methods to the study of dynamic processes in the ribosome offers a new perspective on the mechanism of protein synthesis. Using this technique, the structural and kinetic parameters of tRNA motions within wild‐type and specifically mutated ribosome complexes have been obtained that provide valuable new insights into the mechanism and regulation of translation elongation. The results of these studies are discussed in the context of current knowledge of the ribosome mechanism from both structural and biophysical perspectives. © 2008 Wiley Periodicals, Inc. Biopolymers 89: 565–577, 2008.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Multiple signaling pathways coordinately mediate reactive oxygen species dependent cardiomyocyte hypertrophy
Authors: Indira K. Adiga , Renuka R. Nair 
Published: February 2008

AbstractThe heart responds to an increased demand arising due to physiological stimuli or pathological insults by hypertrophy of myocytes. Reactive oxygen species (ROS) have recently been identified as the molecular intermediates in the translation of mechanical stimuli to cellular response. Different signal transduction pathways have been implicated with cardiac hypertrophy, prominent among them being, mitogen‐activated protein kinase (MAPK), protein kinase C (PKC) and calcineurin. It remains unclear whether the ROS induced hypertrophy is mediated through one or more of these pathways. This study was taken up with the objective to affirm the role of ROS in the induction of cardiomyocyte hypertrophy and examine the contribution of specific pathways in the mediation of the hypertrophic response. The cellular response to enzyme‐generated reactive oxygen species was examined in cultured cells from newborn rat heart. Pathway specific inhibitors were used to identify the role of each pathway in the mediation of cellular hypertrophy. Cellular hypertrophy in response to hypoxanthine‐xanthine oxidase was prevented by inhibition of any one of the pathways; leading to the inference that oxidative stress induced hypertrophy is mediated by coordinative regulation of the three major pathways. Copyright © 2008 John Wiley & Sons, Ltd.
Analytic Models of Domain‐Averaged Fermi Holes: A New Tool for the Study of the Nature of Chemical Bonds
Authors: Ponec Robert , Cooper David L. , Savin Andreas 
Published: February 2008

AbstractSimple analytical models are introduced that significantly enhance the ability to understand and rationalise the nature of bonding interactions depicted by domain‐averaged Fermi hole (DAFH) analysis. The examples presented show that besides shedding new light on the role of electron‐sharing in ordinary two‐centre two‐electron (2c–2e) chemical bonds that are well represented by the classical Lewis model, the proposed approach also provides interesting new insights into the nature of bonding interactions that go beyond the traditional Lewis paradigm. This is, for example, the case of 3c–2e multicentre bonding, but a straightforward extension of the approach also reveals for direct metal–metal bonding the existence of a completely new type of bonding interaction that involves the mutual exchange of electrons between the lone pairs on adjacent metal atoms.
A Novel Green Template for the Synthesis of Mesoporous Silica
Authors: Xu Yeping , Xu Shangjie , Emmler Thomas , Roelofs Frank , Boettcher Christoph , Haag Rainer , Buntkowsky Gerd 
Published: February 2008

AbstractMesoporous pure silicas and functionalized silica with a narrow pore size distribution centered at 3.8 nm were prepared by a novel template, amphiphilic dendritic polyglycerol. The resulting silica materials were characterized by electron microscopy; nitrogen adsorption; 1H, 13C, and 29Si solid‐state cross‐polarization magic‐angle spinning NMR spectroscopy. It was shown that the template could be completely removed from the pure and functionalized silica in an environmentally friendly way by means of a simple water extraction procedure. Furthermore, it was shown that these materials could be easily functionalized, for example, by employing aminopropyl groups. Thus, a new environmentally friendly pathway to this fascinating class of silica material has been opened.
Photoelectron circular dichroism: Chiral asymmetry in the angular distribution of electrons emitted by (+)‐S‐carvone
Authors: Powis Ivan 
Published: February 2008

AbstractThe technique of photoelectron circular dichroism (PECD) is introduced and illustrated by the presentation of results obtained for the C 1s core ionization of (+)‐S‐carvone enantiomers. Using circularly polarized ionizing radiation, large chiral effects in the angular distribution of photoelectrons emitted from a dilute, randomly oriented gas phase sample can be detected. This effect is predicted in the pure electric dipole approximation and is expected to be quite general. The forward–backward asymmetry regularly exceeds 10%, as demonstrated here for the carbonyl C 1s photoemission of carvone. Calculations are presented that reveal a pronounced dependence of this effect on molecular conformation. In the case of carvone the PECD associated with the C 1s electron localized at the carbonyl group varies with orientation of the isopropenyl tail group at the opposite end of the molecule. Comparisons of calculations with experiment confirm the molecular configuration and permit inferences to be drawn concerning the relative conformer populations in the experimental sample. Chirality, 2008. © 2008 Wiley‐Liss, Inc.
Targeted RNA Interference of Cyclin A2 Mediated by Functionalized Single‐Walled Carbon Nanotubes Induces Proliferation Arrest and Apoptosis in Chronic Myelogenous Leukemia K562 Cells
Authors: Wang Xiaohui , Ren Jinsong , Qu Xiaogang 
Published: February 2008

AbstractCyclin A2 plays critical role in DNA replication, transcription, and cell cycle regulation. Its overexpression has been detected and related to many types of cancers including leukemia, suggesting that suppression of cyclin A2 would be an attractive strategy to prevent tumor progression. Herein, we apply functionalized single wall carbon nanotubes (f‐SWNTs) to carry small interfering RNA (siRNA) into K562 cells and determine whether inhibition of cyclin A2 would be a potential therapeutic target for chronic myelogenous leukemia. The results show functionalized SWNTs can facilitate the coupling of siRNA specifically targeting human cyclin A2 to form cyclin A2 siRNA–f‐SWNTs complexes. These functionalized SWNTs readily enter K562 cells, resulting in suppression of cyclin A2 expression. We demonstrate that depletion of cyclin A2 in this manner inhibits cell proliferation and promotes apoptosis, and cyclin A2 can serve as a novel therapeutic target. siRNA against cyclin A2 delivered by functionalized single wall carbon nanotubes may be a useful therapeutic strategy for chronic myelogenous leukemia cells. This would provide new insights on additional therapeutic options for chronic myelogenous leukemia beyond chemotherapy in light of increasing multidrug resistance.
Delayed intervention of sporadic renal masses undergoing active surveillance
Authors: Crispen Paul L. , Viterbo Rosalia , Fox Eric B. , Greenberg Richard E. , Chen David Y. T. , Uzzo Robert G. 
Published: February 2008

AbstractBACKGROUND.Prompt surgical management remains the standard of care for renal cell carcinoma (RCC). Occasionally, it is necessary to postpone or delay surgical treatment. The authors of this report assessed whether delayed intervention following a period of active surveillance altered minimally invasive or nephron‐sparing treatment plans, increased the risk of stage progression, and/or decreased recurrence‐free survival rates.METHODS.The authors searched their institutional kidney cancer database to identify small (≤4 cm in greatest dimension on presentation), enhancing renal masses for which treatment initially was delayed or refused. Clinical, radiographic, and pathologic records were reviewed to determine linear tumor growth kinetics, alterations in treatment plan, stage migration, and cancer‐specific outcomes related to delayed intervention.RESULTS.Eighty‐seven sporadic, localized, enhancing renal masses were identified in 82 patients who had management postponed for a median of 14 months (mean, 21 months; range, 6–97 months). Median tumor diameter was 2.0 cm on presentation. Treatment in 60 of 87 tumors (69%) was delayed for ≥12 months, and treatment was delayed for ≥24 months in 29 of 87 tumors (33%). Overall, 66 of 87 tumors (76%) underwent nephron‐sparing approaches. In addition, 52 of 87 tumors (60%) were treated in a minimally invasive fashion. Pathology confirmed RCC in 73 of 87 treated tumors (84%). Fourteen of 54 tumors (26%) that were treated by surgical extirpation were high‐risk tumors, and 3 of 54 tumors (6%) were upstaged on pathologic review.CONCLUSIONS.The majority of small, sporadic, clinically localized renal tumors demonstrated slow interval growth. The management of these lesions may be delayed cautiously without limiting or complicating the available treatment options or incurring a high risk of disease progression. Cancer 2008. © 2008 American Cancer Society.
Cancer vaccines: Clinical development challenges and proposed regulatory approaches for patient access to promising treatments
Authors: Stebbing Justin , Wood Christopher , Atkins Michael , Bukowski Ronald , Litwin Stephen , Bower Mark , Parsa Andrew , Levitsky Hyam 
Published: February 2008

AbstractThe challenges of late‐stage development increasingly are becoming clear as the clinical development of therapeutic cancer vaccines continues to progress. Preclinical and clinical research had indicated that cancer vaccines exert optimal benefit in earlier stage disease or in adjuvant/minimal residual disease (MRD) settings. However, clinical trials in these settings can be prohibitively slow from a development perspective because of the better prognosis of the patient population and the current lack of early surrogate markers of efficacy. Therefore, the ‘optimal’ patient population (the patient group in which the greatest benefit is demonstrated) for any given vaccine studied in this setting generally must be identified first through the conduct of a large randomized trial for each indication, then confirmed in a second large randomized trial. On the basis of the current regulatory paradigm, a late‐stage development program for a cancer vaccine in the earlier stage disease or adjuvant/MRD setting easily could extend past 10 years. The tight funding environment and constant evolution in medical practice, which can make replication of results from the first trial infeasible over such a long timeline, pose additional challenges. In this report, the authors discuss 3 potential regulatory solutions to better enable the development and commercialization of therapeutic cancer vaccines: a U.S. Food and Drug Administration‐proposed cost‐recovery program, conditional marketing authorization, and a new development paradigm. All of these solutions aim to balance a complex equation of biologic rationale, weight of the evidence for efficacy and safety, regulatory expectations, and cost and timeline of clinical development. Cancer 2008. © 2008 American Cancer Society.
In‐hospital complications of autologous hematopoietic stem cell transplantation for lymphoid malignancies
Authors: Jones Jeffrey A. , Qazilbash Muzaffar H. , Shih Ya‐Chen T. , Cantor Scott B. , Cooksley Catherine D. , Elting Linda S. 
Published: February 2008

AbstractBACKGROUND.Autologous hematopoietic stem cell transplantation (auto HSCT) is standard of care therapy for multiple myeloma and Hodgkin and non‐Hodgkin lymphomas in front‐line and salvage settings, respectively. Complications remain common, but population‐based estimates of their frequency and relative contribution to cost are not available.METHODS.A retrospective cohort comprised of 8891 patients with multiple myeloma and lymphoma admitted to US hospitals for auto HSCT over a 2‐year period (2000‐2001) was extracted from the Nationwide Inpatient Sample (NIS). Patient characteristics, vital status, and total hospital charges were obtained directly from the NIS. Transplant characteristics and outcomes were identified by ICD‐9‐CM codes. Mean hospital charges were examined by outcome and transformed into cost by using Medicare cost‐to‐charge ratios. Factors associated with hospital cost, length of stay, and in‐hospital mortality were explored by using multivariate regression.RESULTS.The mean hospital cost for auto HSCT during this period was $51,312. Significant complications were documented for >50% of admissions. Infectious complications (∼ 60%) and stomatitis (∼ 40%) were the most frequent, and both were associated with increased hospital costs (range, $15,000 to $50,000). In‐hospital mortality was rare (<5%) but was associated with markedly increased cost when it occurred. Pretransplant conditioning with total body irradiation was strongly associated with infectious complications, higher cost, and death.CONCLUSIONS.Adverse events are both common and costly after auto HSCT. Strategies to minimize complications could significantly reduce not only morbidity and mortality but also the cost of the procedure. Administrative data can be profitably exploited to investigate outcomes in this population. Cancer 2008. © 2008 American Cancer Society.