bluuebunny/crossref_metadata_2025 huggingface dataset:
Experience with the Cardiva Boomerang Catalyst™ system in pediatric cardiac catheterization
Authors: Seltzer Sharon , Alejos Juan Carlos , Levi Daniel S.
Published: January 2009

Objectives: We studied the safety and efficacy of the Cardiva Boomerang Catalyst™ vascular closure system in pediatric patients after cardiac catheterization with access in femoral and internal jugular vessels. Background: Recurrent catheterization and advances in pediatric interventions increase the need for easy hemostasis without a residual foreign body that may prevent re‐accessing the vessel. The Boomerang can be deployed in sheaths as small as 4Fr without residual foreign body, with minimal orientation needed, and few complications reported. Methods: In a two‐month period, all patients between 18 months and 21 years old catheterized with 4–8Fr sheaths less than 15 cm long were eligible for Boomerang placement. These were compared retrospectively with control patients with manual hemostasis. Anthropomorphic measurements, procedure type, activated clotting time, and sheath size as well as total times of cases, intubation, hemostasis, and extubation were compared between the two groups. Results: Forty‐six Boomerangs were deployed in 31 patients and compared with 40 patients with manual hemostasis. Boomerangs were deployed in femoral vessels and the internal jugular vein. Device success with hemostasis was achieved in 39 patients (85%). There were no significant differences in time to hemostasis or extubation between the two groups. No major complications or operator error occurred, including hematoma, transfusion, retroperitoneal bleed, infection, vessel occlusion, or need for surgery. Conclusions: The Boomerang is a safe and easy means of achieving hemostasis in the pediatric population, in femoral vessels as well as internal jugular veins. Its times to hemostasis and extubation were not significantly different from manual hold. © 2009 Wiley‐Liss, Inc.
Copper(II) Biosorption on Soda Lignin From Oil Palm Empty Fruit Bunches (EFB)
Authors: Ibrahim Mohamad Nasir Mohamad , Ngah Wan Saime Wan , Norliyana Mohd Salleh , Daud Wan Rosli Wan
Published: January 2009

The adsorption of Cu(II) ions from aqueous solutions by soda lignin as an absorbent using a batch adsorption system is presented in this paper. The soda lignin used in this study was extracted from black liquor derived from oil palm empty fruit bunches (EFB) using 20% v/v sulfuric acid. The effects of varying experimental parameters such as pH value, adsorbent dosage, different concentrations of Cu(II) ions, and agitation period were investigated. The results revealed that the optimum adsorption of Cu(II) onto soda lignin was recorded at a pH of 5.0 at an adsorbent dosage of 0.5 g soda lignin and an agitation period of 40 min. The adsorption capacities and rates of Cu(II) ions onto soda lignin was evaluated. The Langmuir and Freundlich adsorption models were applied to calculate the isotherm constants. It was found that the adsorption isothermal data could be well interpreted by the Freundlich model. The kinetic experimental data properly correlated with the pseudo‐second‐order kinetic model, which implies that chemical sorption is the rate‐limiting step.
Low positive predictive value of the oral brush biopsy in detecting dysplastic oral lesions
Authors: Bhoopathi Vinodh , Kabani Sadru , Mascarenhas Ana Karina
Published: January 2009

BACKGROUND:

The authors evaluated the effectiveness of the oral brush biopsy technique as a diagnostic tool in detecting dysplastic oral lesions.

METHODS:

In this cross‐sectional study, pathologic reports (n = 152) from the scalpel biopsies (tissue samples) in patients who previously tested either “positive” (n = 3) or “atypical” (n = 149) for dysplasia by brush biopsy (OralCDx) were evaluated. Information on the age and sex of the patient, the site of the lesion, the brush biopsy results, and the histopathologic diagnosis of the scalpel biopsy was collected. The positive predictive values (PPVs) for “abnormal,” “atypical,” and “positive” brush biopsies were determined.

RESULTS:

Overall, the PPV of an abnormal brush biopsy was only 7.9% (95% confidence interval [CI], 4.2%‐13.4%), and the PPV of an “atypical” brush biopsy was 7.4% (95% CI, 3.7%‐12.8%). Of the 3 positive brush biopsies, only 1 was identified as dysplastic. The proportion of false‐positive biopsy results was as high as 92.1% (95% CI, 86.6%‐95.9%).

CONCLUSIONS:

The OralCDx technique overestimated dysplastic lesions and produced a high number of false‐positive results. Cancer 2009. © 2009 American Cancer Society.
Routine perioperative chemotherapy instillation with initial bladder tumor resection
Authors: Rao Pravin K. , Stephen Jones J.
Published: January 2009

BACKGROUND:

Level‐1 evidence has demonstrated decreased recurrence of low‐grade bladder tumors when initial transurethral resection (TUR) is followed by perioperative instillation (PI) of chemotherapy. A meta‐analysis determined that the number needed to treat (NNT) was 8.5 patients to prevent 1 recurrence. No benefit was demonstrated for tumors classified as T0, tumor in situ, or T2; thus, patients with those tumors were excluded from the analysis, which potentially may have resulted in underestimating the true NNT. Economic benefits were suggested, but cost calculations were not presented. The objectives of the current analysis were to recalculate the NNT considering patients who previously were excluded and to examine the economic implications based on various management alternatives for tumor recurrence.

METHODS:

For each study that was included in the current meta‐analysis, the number of patients excluded because of ‘inappropriate’ pathology results was determined. A potentially more accurate NNT was calculated, and pertinent Medicare reimbursements were obtained to estimate costs.

RESULTS:

The added cost for 8.5 patients who underwent inpatient TUR to receive PI was $1711. Inpatient TUR ($7025) was extremely costly compared with hospital outpatient TUR ($2666), ambulatory surgery center TUR ($2113), and physician office fulguration ($1167). Although the inclusion of patients who previously were excluded resulted in a recalculated NNT of 9.6 patients, the authors used a more conservative NNT if 8.5 patients to estimate the economic impact of the ‘best‐case scenario.’

CONCLUSIONS:

Routine PI significantly lowered the overall cost if recurrences were managed in the inpatient setting, but these benefits were offset mostly or completely by outpatient management in the United States. Thus, the authors concluded that the decision to use routine PI of chemotherapy should be based on clinical effects and not on presumed economic benefits. Cancer 2009. © 2009 American Cancer Society.
A multifunctional reporter mouse line for Cre‐ and FLP‐dependent lineage analysis
Authors: Yamamoto Masakazu , Shook Nicole A. , Kanisicak Onur , Yamamoto Shoko , Wosczyna Michael N. , Camp James R. , Goldhamer David J.
Published: January 2009

The Cre/lox and FLP/FRT recombination systems have been used extensively for both conditional knockout and cell lineage analysis in mice. Here we report a new multifunctional Cre/FLP dual reporter allele (R26NZG) that exhibits strong and apparently ubiquitous marker expression in embryos and adults. The reporter construct, which is driven by the CAG promoter, was knocked into the ROSA26 locus providing an open chromatin domain for consistent expression and avoiding site‐of‐integration effects often observed with transgenic reporters. R26NZG directs Cre‐dependent nuclear‐localized β‐galactosidase (β‐gal) expression, and can be converted into a Cre‐dependent EGFP reporter (R26NG) by germline excision of the FRT‐flanked nlslacZ cassette. Alternatively, germline excision of the floxed PGKNEO cassette in R26NZG generates an FLP‐dependent EGFP reporter (R26ZG) that expresses β‐gal in FLP‐nonexpressing cells. Finally, by the simultaneous use of both Cre and FLP deleters, R26NZG allows lineage relationships to be interrogated with greater refinement than is possible with single recombinase reporter systems. genesis 47:107–114, 2009. © 2009 Wiley‐Liss, Inc.
Synthesis of Phenanthro[9,10‐b]indolizidin‐9‐ones, Phenanthro[9,10‐b]quinolizidin‐9‐one, and Related Benzolactams by Pd(OAc)2‐Catalyzed Direct Aromatic Carbonylation
Authors: Yamashita Satoshi , Kurono Nobuhito , Senboku Hisanori , Tokuda Masao , Orito Kazuhiko
Published: January 2009

Phenanthro[9,10‐b]indolizidin‐9‐ones, phenanthro[9,10‐b]quinolizidin‐9‐one, and related benzolactams were synthesized by benzolactam ring formation using Pd(OAc)2‐catalyzed direct aromatic carbonylation. This also constitutes a formal synthesis of the representative phenanthroindolizidine and ‐quinolizidine alkaloids (±)‐tylophorine, (±)‐antofine, and (±)‐cryptopleurine.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Palladium‐Catalyzed Three‐Component Coupling Reactions: 1,1‐Difunctionalization of Activated Alkenes
Authors: Rodriguez Arantxa , Moran Wesley J.
Published: January 2009

A three‐component coupling reaction was developed to access 3,3‐oxyarylpropionate derivatives. Each of the three reaction components can be varied, allowing the modular synthesis of a range of important chiral building blocks. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Electrochemical Study of Anionic Ferrocene Derivatives Intercalated in Layered Double Hydroxides: Application to Glucose Amperometric Biosensors
Authors: Mousty Christine , Forano Claude , Fleutot Solenne , Dupin Jean‐Charles
Published: January 2009

Layered double hydroxides (Zn2Cr(OH)6X⋅nH2O LDH) containing (3‐sulfopropyl)ferrocene‐carboxylate (FcPSO3) and 1,1′‐bis(3‐sulfopropyl)ferrocene‐carboxylate (Fc(PSO3)2) as interlayer anions (X) have been prepared by the co‐precipitation method and characterized by PXRD, FTIR, SEM and XPS. The electrochemical behavior of these hybrid materials has been evaluated by cyclic voltammetry. A new amperometric biosensor based on the immobilization of glucose oxidase in ZnCr‐FcPSO3 hybrid material was presented, the intercalated anions playing the role of mediators that shuttle electrons between the FAD centers in the enzyme and the electrode surface. The performance of the resulting biosensor for glucose determination under anaerobic conditions was evaluated by chronoamperometry at 0.5 V. The sensitivity (65 mA M−1 cm−2) determined in the concentration range 10–25 μM is higher than sensitivities reported for other glucose biosensors based on LDH host matrices.
Hybrid Microfluidic Sensors Fabricated by Screen Printing and Injection Molding for Electrochemical and Electrochemiluminescence Detection
Authors: Redha Zainab Mohammed , Baldock Sara. J. , Fielden Peter R. , Goddard Nick J. , Brown Bernard J. Treves , Haggett Barry G. D. , Andres Roberto , Birch Brian J.
Published: January 2009

An integrated microfluidic/electrochemical sensor with a dual working electrode configuration was fabricated for voltammetric and electrochemiluminescence (ECL) applications. The fabrication method integrates the two techniques of injection molding and screen printing for the first time. Injection molding is used to fabricate the flow cell with integrated electrical and fluidic connectors. Screen printing was used to print the electrodes directly onto the injection molded base plate. An over molding procedure followed by ultrasonic welding was used to form the complete sensor. The electrochemical and ECL performance of the sensors was assessed by applying different electrochemical methods such as cyclic voltammetry (CV), anodic stripping voltammetry (ASV) and chronoamperometry. The attractive analytical performance demonstrates good capability of the disposable sensors for routine on‐line electrochemical and ECL measurements.
What Do We Know about Determination of Amino Acids with Orthophthalaldehyde?
Authors: Zuman Petr , Salem Nuha , Kulla Eliona
Published: January 2009

Mechanisms of the formation of the fluorescent species widely used for determination of amino acids, based on reaction with orthophthalaldehyde (OPA) were unknown. Attempts to elucidate this mechanism based solely on product identification were unsuccessful. Analytical methods based on reaction of OPA with amino acids in the presence of RS− or CN− ions were developed empirically. The reaction conditions reported in more than 700 papers differed considerably. In aqueous solutions OPA exists in three different forms in equilibrium – the unhydrated form Ia (20%), monohydrated acyclic form Ib (8%) and cyclic hemiacetal form Ic (72%). These forms are in equilibria, the rate of establishment of which is acid and base catalyzed. Reactions of OPA and NH3 and 2‐aminoethanol (colamine) take place in a series of equilibria depicted in Scheme 1. The isoindole derivatives are formed in cyclization of the carbinolamine. Formation of an imine is a side reaction.
Interaction of Biomacromolecules with Surfaces Viewed by Electrochemical Methods
Authors: Dorčák V. , Bartošík M. , Ostatná V. , Paleček E. , Heyrovský M.
Published: January 2009

The electrocatalytic evolution of hydrogen on mercury electrodes by organic molecules indicates, when followed with chronopotentiometric stripping method by the ‘peak H’, that when the stripping current is changed, the mechanism of the electrode process changes. The changes become the more prominent the larger is the catalyzing organic molecule. We explain this phenomenon by dynamic interaction of the catalyzing molecule with the electrode surface.
Biosensors Based on Poly(vinylimidazole) Microparticles
Authors: Sánchez‐Paniagua López M. , López‐Cabarcos E. , López Ruiz B.
Published: January 2009

The use of poly(vinylimidazole) microparticles as immobilization system of the enzymes used as biological material in the fabrication of glucose and catechol biosensors is proposed. Biosensors analytical properties were studied using different working media: aqueous buffer solution and solvents with different hydrophobicity such as dioxane (lgP=−1.1), acetonitrile (lgP=−0.33), ethanol (lgP=−0.24), chloroform (lgP=2.0) and hexane (lgP=3.5) as well as different mixtures of acetonitrile/aqueous buffer solution. Sensitivity, detection limit, linear range and response time were reported for both biosensors in both media. The performance of the biosensors in the analysis of glucose and phenols in real samples was successful.
A hypothetical reality of Tarrawarra‐like hydrologic response
Authors: Mirus Benjamin B. , Loague Keith , VanderKwaak Joel E. , Kampf Stephanie K. , Burges Stephen J.
Published: January 2009

The objective of this work was to develop a hypothetical reality of hydrologic response to be used as an error‐free synthetic dataset in a larger ongoing study. The hypothetical reality was generated via rigorous simulation of a real system with a comprehensive physics‐based model. The simulation was conducted with the Integrated Hydrology Model (InHM); the system is the Tarrawarra catchment located in southeastern Australia. Parameterization of the Tarrawarra boundary‐value problem was based on the best available information, which, for example includes rainfall, discharge, and soil‐water content data for the last six months of 1996. The InHM‐simulated near‐surface hydrologic response for the Tarrawarra boundary‐value problem compares well (albeit not perfectly) with both the integrated and distributed observations from the catchment. The Tarrawarra‐like hypothetical reality of wet season hydrologic response generated in this study is rich enough to be employed as an error‐free synthetic dataset for quantitatively evaluating the capabilities/limitations of competing (underlying) modelling techniques. Copyright © 2009 John Wiley & Sons, Ltd.
Population‐based study of autoimmune conditions and the risk of specific lymphoid malignancies
Authors: Anderson Lesley A. , Gadalla Shahinaz , Morton Lindsay M. , Landgren Ola , Pfeiffer Ruth , Warren Joan L. , Berndt Sonja I. , Ricker Winnie , Parsons Ruth , Engels Eric A.
Published: January 2009

Some autoimmune conditions are associated with increased risk of lymphoid malignancies, but information on specific malignancy subtypes is limited. From the U.S. Surveillance Epidemiology and End Results‐Medicare database, we selected 44,350 lymphoid malignancy cases (≥67 years) and 122,531 population‐based controls. Logistic regression was used to derive odds ratios (ORs) comparing the prevalence of autoimmune conditions in cases and controls, by lymphoid malignancy subtype, adjusted for gender, age at malignancy/selection, year of malignancy/selection, race and number of physician claims. The strongest associations observed by non‐Hodgkin lymphoma (NHL) subtypes were diffuse large B‐cell lymphoma with rheumatoid arthritis (OR 1.4, 95%CI 1.2–1.5) and Sjögren syndrome (2.0, 1.5–2.8); T‐cell lymphoma with hemolytic anemia (9.7, 4.3–22), psoriasis (3.1, 2.5–4.0), discoid lupus erythematosus (4.4, 2.3–8.4) and celiac disease (5.0, 2.4–14.); and marginal zone lymphoma with Sjögren syndrome (6.6, 4.6–9.5), systemic lupus erythematosus (2.8, 1.7–4.7) and hemolytic anemia (7.4, 3.1–18). Hodgkin lymphoma was associated with systemic lupus erythematosus (3.5, 1.9–6.7). Multiple myeloma was associated only with pernicious anemia (1.5, 1.3–1.7). Several autoimmune conditions were associated with increased risk of lymphoid neoplasms, especially NHLs of diffuse large B‐cell, marginal zone and T‐cell subtypes. These results support a mechanism whereby chronic antigenic stimulation leads to lymphoid malignancy. Published 2009 UICC.
Selective inhibition of proliferation in colorectal carcinoma cell lines expressing mutant APC or activated B‐Raf
Authors: Zhang Hui‐Hua , Walker Francesca , Kiflemariam Sara , Whitehead Robert H. , Williams David , Phillips Wayne A. , Mikeska Thomas , Dobrovic Alexander , Burgess Antony W.
Published: January 2009

Tumor‐derived cell lines are indispensable tools for understanding the contribution of activated signaling pathways to the cancer phenotype and for the design and testing of targeted signal therapies. In our study, we characterize 10 colorectal carcinoma cell lines for the presence of mutations in the wnt, Ras/MAPK, PI3K and p53 pathways. The mutational spectrum found in this panel of cell lines is similar to that detected in primary CRC, albeit with higher frequency of mutation in the β‐catenin and B‐Raf genes. We have monitored activation of the wnt and Ras/MAPK pathways in these cells and analyzed their sensitivity to selective signaling inhibitors. Using β‐catenin subcellular distribution as a marker, we show that cells harboring APC mutations have low‐level activated wnt signaling, which can be blocked by the extracellular wnt inhibitor DKK‐1, suggesting autocrine activation of this pathway; proliferation of these cells is also blocked by DKK‐1. In contrast, cells with β‐catenin mutations are unresponsive to extracellular wnt inhibition. Constitutive phosphorylation of MAPK is present in the majority of the cell lines and correlates with B‐Raf but not K‐Ras mutations; correspondingly, the proliferation of cells harboring mutations in B‐Raf, but not K‐Ras, is exquisitely sensitive inhibition of the MAPK pathway. We find no correlation between PI3K mutation or loss of PTEN expression and increased sensitivity to PI3K inhibitors. Our study discloses clear‐cut differences in responsiveness to signaling inhibitors between individual mutations within an activated signaling pathway and suggests likely targets for signal‐directed therapy of colorectal carcinomas. © 2009 UICC
Survivin minigene DNA vaccination is effective against neuroblastoma
Authors: Fest Stefan , Huebener Nicole , Bleeke Matthias , Durmus Tahir , Stermann Alexander , Woehler Anja , Baykan Bianca , Zenclussen Ana C. , Michalsky Elke , Jaeger Ines S. , Preissner Robert , Hohn Oliver , Weixler Silke , Gaedicke Gerhard , Lode Holger N.
Published: January 2009

The inhibitor of apoptosis protein survivin is highly expressed in neuroblastoma (NB) and survivin‐specific T cells were identified in Stage 4 patients. Therefore, we generated a novel survivin minigene DNA vaccine (pUS‐high) encoding exclusively for survivin‐derived peptides with superior MHC class I (H2‐Kk) binding affinities and tested its efficacy to suppress tumor growth and metastases in a syngeneic NB mouse model. Vaccination was performed by oral gavage of attenuated Salmonella typhimurium SL7207 carrying pUS‐high. Mice receiving the pUS‐high in the prophylactic setting presented a 48–52% reduction in s.c. tumor volume, weight and liver metastasis level in contrast to empty vector controls. This response was as effective as a survivin full‐length vaccine and was associated with an increased target cell lysis, increased presence of CD8+ T‐cells at the primary tumor site and enhanced production of proinflammatory cytokines by systemic CD8+ T cells. Furthermore, depletion of CD8+ but not CD4+ T‐cells completely abrogated the pUS‐high mediated primary tumor growth suppression, demonstrating a CD8+ T‐cell mediated effect. Therapeutic vaccination with pUS‐high led to complete NB eradication in over 50% of immunized mice and surviving mice showed an over 80% reduction in primary tumor growth upon rechallenge in contrast to controls. In summary, survivin‐based DNA vaccination is effective against NB and the rational minigene design provides a promising approach to circumvent potentially hazardous effects of using full length antiapoptotic genes as DNA vaccines. © 2009 UICC
NF‐κB inhibition triggers death of imatinib‐sensitive and imatinib‐resistant chronic myeloid leukemia cells including T315I Bcr‐Abl mutants
Authors: Lounnas Nadia , Frelin Catherine , Gonthier Nadège , Colosetti Pascal , Sirvent Anne , Cassuto Jil‐Patrice , Berthier Fréderic , Sirvent Nicolas , Rousselot Philippe , Dreano Michel , Peyron Jean‐François , Imbert Véronique
Published: January 2009

The Bcr‐Abl inhibitor imatinib is the current first‐line therapy for all newly diagnosed chronic myeloid leukemia (CML). Nevertheless, resistance to imatinib emerges as CML progresses to an acute deadly phase implying that physiopathologically relevant cellular targets should be validated to develop alternative therapeutic strategies. The NF‐κB transcription factor that exerts pro‐survival actions is found abnormally active in numerous hematologic malignancies. In the present study, using Bcr‐Abl‐transfected BaF murine cells, LAMA84 human CML cell line and primary CML, we show that NF‐κB is active downstream of Bcr‐Abl. Pharmacological blockade of NF‐κB by the IKK2 inhibitor AS602868 prevented survival of BaF cells expressing either wild‐type, M351T or T315I imatinib‐resistant mutant forms of Bcr‐Abl both in vitro and in vivo using a mouse xenograft model. AS602868 also affected the survival of LAMA84 cells and of an imatinib‐resistant variant. Importantly, the IKK2 inhibitor strongly decreased in vitro survival and ability to form hematopoietic colonies of primary imatinib resistant CML cells including T315I cells. Our data strongly support the targeting of NF‐κB as a promising new therapeutic opportunity for the treatment of imatinib resistant CML patients in particular in the case of T315I patients. The T315I mutation escapes all currently used Bcr‐Abl inhibitors and is likely to become a major clinical problem as it is associated with a poor clinical outcome. © 2009 UICC
Structural studies of conotoxins
Authors: Daly Norelle L. , Craik David J.
Published: January 2009

Conotoxins are small disulfide‐rich peptides from the venoms of marine cone snails. They target a variety of ion channels, transporters, and receptors besides the interest in their natural functions in venoms and they are of much interest as drug leads. This short article gives an overview of the structural diversity of conotoxins, and illustrates this diversity with recent selected examples of conotoxin structures. © 2009 IUBMB IUBMB Life, 61(2): 144–150, 2009
Initial investigation of novel human‐like collagen/chitosan scaffold for vascular tissue engineering
Authors: Zhu Chenhui , Fan Daidi , Duan Zhiguang , Xue Wenjiao , Shang Longan , Chen Fulin , Luo Yane
Published: January 2009

With the increasing occurrence of vascular diseases and poor long‐term patency rates of current small diameter vascular grafts, it becomes urgent to pursuit biomaterial as scaffold to mimic blood vessel morphologically and mechanically. In this study, novel human‐like collagen (HLC, produced by recombinant E. coli)/chitosan tubular scaffolds were fabricated by cross‐linking and freeze‐drying process. The scaffolds were characterized by scanning electron microscope (SEM), X‐ray photoelectron spectroscopy (XPS), and tensile test, respectively. Human venous fibroblasts were expanded and seeded onto the scaffolds in the density of 1 × 105 cells/cm2. After a 15‐day culture under static conditions, the cell–polymer constructs were observed using SEM, confocal laser scanning microscopy (CLSM), histological examination, and biochemical assays for cell proliferation and extracellular matrix production (collagen and glycosaminoglycans). Furthermore, the scaffolds were implanted into rabbits' livers to evaluate their biocompatibility. The results indicated that HLC/chitosan tubular scaffolds (1) exhibited interconnected porous structure; (2) achieved the desirable levels of pliability (elastic up to 30% strain) and stress of 300 ± 16 kPa; (3) were capable of enhancing cell adhesion and proliferation and ECM secretion; (4) showed superior biocompatibility. This study suggested the feasibility of HLC/chitosan composite as a promising candidate scaffold for blood vessel tissue engineering. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res 2009
A bovine acellular scaffold for vocal fold reconstruction in a rat model
Authors: Xu Chet C. , Chan Roger W. , Weinberger Debra G. , Efune Guy , Pawlowski Karen S.
Published: January 2009

With a rat model of vocal fold injury, this study examined the in vivo host response to an acellular xenogeneic scaffold derived from the bovine vocal fold lamina propria, and the potential of the scaffold for constructive tissue remodeling. Bilateral wounds were created in the posterior vocal folds of 20 rats, and bovine acellular scaffolds were implanted into the wounds unilaterally, with the contralateral vocal folds as control. The rats were humanely sacrificed after 3 days, 7 days, 1 month, and 3 months, and the coronal sections of their larynges were examined histologically. Expressions of key matrix proteins including collagen I, collagen III, elastin, fibronectin, hyaluronic acid, and glycosaminoglycans (GAGs) were quantified with digital image analysis. Significant infiltration of host inflammatory cells and host fibroblasts in the scaffold implant was observed in the acute stage of wound repair (3 days and 7 days postsurgery). The mean relative densities of collagen I, collagen III, and GAGs in the implanted vocal folds were significantly higher than those in the control after 3 days, followed by gradual decreases over 3 months. Histological results showed that the scaffolds were apparently degraded by 3 months, with no fibrotic tissue formation or calcification. These preliminary findings suggested that the bovine acellular scaffold could be a potential xenograft for vocal fold regeneration. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Enhancing annulus fibrosus tissue formation in porous silk scaffolds
Authors: Chang Godfrey , Kim Hyeon Joo , Vunjak‐Novakovic Gordana , Kaplan David L. , Kandel Rita
Published: January 2009

There is presently no optimal treatment for patients with chronic back pain as a result of degenerative disc disease. Tissue engineering, an annulus fibrosus (AF) construct suitable to repair the damaged AF, is one novel approach to the treatment of this disease. We have previously demonstrated that porous silk scaffolds can support AF cell attachment and extracellular matrix accumulation; however, tissue infiltration and matrix accumulation was not optimal. The purpose of this study was to determine whether the dynamic culture of AF cells seeded into larger average pore size silk scaffolds would improve tissue formation. AF cells were isolated from bovine caudal discs and seeded into porous silk scaffolds and grown in either dynamic or static flow conditions. The cell‐seeded scaffolds were grown for up to 4 weeks and evaluated for cell attachment, gene expression, histological appearance, and matrix accumulation. Dynamic culture improved AF tissue formation as the tissue was more cellular and contained significantly more matrix than that formed in static culture. Spatial distribution of tissue was comparable for static and dynamic culture. Varying scaffold pore sizes (200‐, 600‐, and 1000‐μm pore size) demonstrated that an average pore size of 600 μm resulted in the most uniform tissue distribution with the greatest amount of type I collagen. Our study suggests that dynamic flow conditions and scaffold pore size can affect the formation of engineered AF tissue. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Bone remodeling in a new biomimetic polymer‐composite hip stem
Authors: Bougherara Habiba , Bureau Martin N. , Yahia L'Hocine
Published: January 2009

Adaptive bone remodeling is an important factor that leads to bone resorption in the surrounding femoral bone and implant loosening. Taking into account this factor in the design of hip implants is of clinical importance, because it allows the prediction of the bone‐density redistribution and enables the monitoring of bone adaptation after prosthetic implantation. In this article, adaptive bone remodeling around a new biomimetic polymer‐composite‐based (CF/PA12) hip prosthesis is investigated to evaluate the amount of stress shielding and bone resorption. The design concept of this new prosthesis is based on a hollow substructure made of hydroxyapatite‐coated, continuous carbon fiber (CF)‐reinforced polyamide 12 (PA12) composite with an internal soft polymer‐based core. Strain energy density theory coupled with 3D Finite Element models is used to predict bone density redistributions in the femoral bone before and after total hip replacement (THR) using both polymer‐composite and titanium (Ti) stems. The result of numerical simulations of bone remodeling revealed that the CF/PA12 composite stem generates a better bone density pattern compared with the Ti‐based stem, indicating the effectiveness of the composite stem to reduce bone resorption caused by stress‐shielding phenomenon. This may result in an extended lifetime of THR. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Preparation and in vivo evaluation of apatite/collagen packed composite by alternate immersion method and Newton press
Authors: Taira Masayuki , Nezu Takashi , Sasaki Kaori , Saitoh Setsuo , Kagiya Tadayoshi , Harada Hidemitsu , Takada Yukyo , Araki Yoshima
Published: January 2009

Further development of bio‐compatible, bio‐absorbable, and osteo‐conductive bio‐materials is desired for bone grafts in dental and medical clinics. One candidate material might be a high‐density apatite/collagen composite, which cures relatively large bone defects. To produce such a composite, we freeze‐dried type I collagen solution, cross‐linked the formed sponge by 2 wt % glutaraldehyde, immersed the insoluble sponge in CaCl2 and Na2HPO4 solutions alternately five times, and compacted the sponge by Newton press at 5000 kgf. For comparison, cross‐linked collagen without alternate immersion was also pressed. SEM/EPMA, XRD, and FTIR analyses clarified that alternate immersion successfully coated the collagen sponge with hydroxyapatite. Packed apatite/collagen composite and collagen disks 6 mm in diameter and 0.5 mm in height were implanted in the subperiostea of rabbit tibiae for 2, 4, 8, and 12 weeks to assess bio‐compatibility, bio‐absorbability, and osteo‐conductivity. Histological observations showed that the packed apatite/collagen composite was biocompatible, osteo‐conductive for up to 8 weeks, and largely bio‐absorbed at 12 weeks, while the packed collagen sponge caused an undesirable foreign body reaction, which worsened with the implantation period. The overall findings suggest that this packed apatite/collagen composite might be used as a new bio‐absorbable bone graft material. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2009
Cytoprotective effects of the lipoidic‐liquiform pro‐vitamin C tetra‐isopalmitoyl‐ascorbate (VC‐IP) against ultraviolet‐A ray‐induced injuries in human skin cells together with collagen retention, MMP inhibition and p53 gene repression
Authors: Xiao Li , Kaneyasu Kentaro , Saitoh Yasukazu , Terashima Yoichi , Kowata Yasunori , Miwa Nobuhiko
Published: January 2009

Irradiation with ultraviolet‐A (UVA) ray at doses of 20–100 J/cm2 diminished the cell viability of human keratinocytes HaCaT and human melanoma cells HMV‐II, both of which were protected by pre‐irradiational administration with the ascorbic acid (Asc) derivative, VC‐IP (2,3,5,6‐O‐tetra‐2′‐hexyldecanoyl‐L‐ascorbic acid; vitamin C‐isopalmityl tetraester), which is the first lipoidic‐liquiform pro‐vitamin C by itself that is materialized by esterization of all four intramolecular hydroxyl groups of an Asc molecule with branched chain fatty groups, resulting in molecular fluidity higher than that of the corresponding straight chains. Irradiation with UVA to HaCaT keratinocytes was shown to cause the formation of 8‐hydroxydeoxyguanosine (8‐OHdG), translocation of phosphatidylserine in the inner layer into the outer layer of cell membrane, and lowering of a mitochondrial membrane potential, all of which were repressed by pre‐irradiational administration with VC‐IP. Expression of p53 gene, another hallmark of UV‐induced DNA damages, was promoted by UVA irradiation to the keratinocytes but also repressed by VC‐IP. Administration with VC‐IP of 10–50 µM to human fibroblasts NHDF achieved the enhancement of collagen synthesis, repression of matrix metalloprotease‐2/9 activity, and increasing of intracellular Asc contents more markedly than that with Asc itself of the same concentrations. Thus UVA‐induced diverse harmful effects could be prevented by VC‐IP, which was suggested to ensue intrinsically from the persistent enrichment of intracellular Asc, through esterolytic conversion of VC‐IP to a free‐form Asc molecule, resulting in relief to UVA‐caused oxidative stress. J. Cell. Biochem. 106: 589–598, 2009. © 2009 Wiley‐Liss, Inc.
In situ indentation of nanoporous gold thin films in the transmission electron microscope
Authors: Sun Ye , Ye Jia , Minor Andrew M. , Balk T. John
Published: January 2009

The mechanical behavior of nanoporous gold was investigated during in situ nanoindentation in the transmission electron microscope. Thin films of nanoporous gold, with ligaments and pores of the order of 10‐nm diameter, offer a highly constrained geometry for deformation and thus provide an opportunity to study the role of defects such as dislocations in the plasticity of nanomaterials. Films ranging in thickness from 75 to 300 nm were indented, while the motion of dislocations and deformation of ligaments were observed in situ. Dislocations were generated and moved along ligament axes, after which they interacted with other dislocations in the nodes of the porous network. For thicker films, the load‐displacement curves exhibited load drops at regular intervals. The question of whether the spacing of these load drops was related to the collapse of pores in the nanoporous films or due to bursts of plasticity within the ligaments was investigated. Additionally, the effect of the indenter displacement rate on the mechanical response of these gold films with nanoscale porosity was investigated. Indentation rates were varied from 1.5 to 30 nm/s. There appears to be a kinetic factor related to dislocation nucleation, where slower displacement rates cause load drops to occur at shorter distance intervals and over longer time intervals. Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc.
Digital titration: Automated image acquisition and analysis of load and growth of Chlamydophila psittaci
Authors: Beeckman Delphine S.A. , Meesen Geert , Van Oostveldt Patrick , Vanrompay Daisy
Published: January 2009

Traditionally, the amount of infective chlamydiae in a given sample is determined by inoculating dilution series into cell cultures and physically counting chlamydial inclusions. This approach is time consuming, tedious, and error prone, mainly when dealing with high titers. Therefore, this paper describes a largely automated technique that was developed to standardize the determination of chlamydial load in vitro. Cells are fixed at 36 h post‐inoculation and bacteria visualized using standard immunological detection methods. Consequently, for 81 microscopic fields, an image is recorded at the interpolated focal plane. These images are then automatically processed using an ImageJ plugin and the obtained results are imported into Excel to determine the number of inclusion forming units per mL in the sample. The main advantage of this technique is that no or minimal sample dilution is required, thus minimizing dilution errors. In addition, this technique was employed during the early, middle and late growth stages of the chlamydial developmental cycle and results correlated well (P < 0.01) with 16S rRNA values from previous experiments, thereby proving its suitability to follow chlamydial growth in vitro. The method described is highly suitable for high throughput titration of cell culture inoculated samples and assessment of possible antichlamydial effects of novel compounds throughout the chlamydial growth cycle. Microsc. Res. Tech., 2009. © 2009 Wiley‐Liss, Inc.
Contribution of the tooth bud mesenchyme to alveolar bone
Authors: Diep Lisa , Matalova Eva , Mitsiadis Thimios A. , Tucker Abigail S.
Published: January 2009

This study highlights the dynamic nature of the mesenchymal cells during tooth development from the bud to the bell stage. Condensing mesenchymal cells, labelled on either side of the developing tooth bud, move toward the presumptive roots forming an arc of cells under the dental papilla. These labelled cells take part in formation of the dental follicle, which contributes to both the tooth and its surrounding periodontium, including the supporting alveolar bone. This study, thus, physically links development of the tooth with the tissue into which it develops. The results obtained clearly indicate that the tooth organ is an entity comprising dental and periodontal tissue. J. Exp. Zool. (Mol. Dev. Evol.) 312B:510–517, 2009. © 2009 Wiley‐Liss, Inc.
In vivo metabolite profile of adult zebrafish brain obtained by high‐resolution localized magnetic resonance spectroscopy
Authors: Kabli Samira , Spaink Herman P. , De Groot Huub J.M. , Alia A.
Published: January 2009

Purpose

To optimize high‐resolution MR spectroscopy (MRS) for obtaining neurochemical composition of adult zebrafish brain in vivo.

Materials and Methods

A flow‐through setup for supporting MRS of living zebrafish has been designed. In vivo MR microscopy (MRM) images were obtained using a rapid acquisition with relaxation enhancement (RARE) sequence to select a volume of interest. In vivo MR spectra from zebrafish brain were obtained using an optimized point‐resolved spectroscopy (PRESS) sequence preceded by a variable pulse power and optimized relaxation delays (VAPOR) sequence for global water suppression interleaved with outer volume suppression (OVS). In vitro MR spectra in the brain extract were obtained by using correlated spectroscopy (COSY) sequences.

Results

Optimized high‐resolution localized MRS at 9.4T in conjunction with a strong gradient system, efficient shimming, and the water suppression scheme resulted in a reasonable separation of resonances from various metabolites in vivo from a voxel as small as 3.3 μL placed in the zebrafish brain. In addition, more than 14 metabolites were identified in adult zebrafish brain extracts.

Conclusion

We have successfully optimized a high‐resolution localized in vivo MRS technique to get access to the zebrafish brain, and obtained for the first time the neurochemical composition of the zebrafish brain. J. Magn. Reson. Imaging 2009;29:275–281. © 2009 Wiley‐Liss, Inc.
T2 relaxometry of normal pediatric brain development
Authors: Leppert Ilana R. , Almli C. Robert , McKinstry Robert C. , Mulkern Robert V. , Pierpaoli Carlo , Rivkin Michael J. , Pike G. Bruce
Published: January 2009

Purpose

To establish normal age‐related changes in the magnetic resonance (MR) T2 relaxation time constants of brain using data collected as part of the National Institutes of Health (NIH) MRI Study of Normal Brain Development.

Materials and Methods

This multicenter study of normal brain and behavior development provides both longitudinal and cross‐sectional data, and has enabled us to investigate T2 evolution in several brain regions in healthy children within the age range of birth through 4 years 5 months. Due to the multicenter nature of the study and the extended period of data collection, periodically scanned inanimate and human phantoms were used to assess intra‐ and intersite variability.

Results

The main finding of this work, based on over 340 scans, is the identification and parameterization of the monoexponential evolution of T2 from birth through 4 years 5 months of age in various brain structures.

Conclusion

The exponentially decaying T2 behavior is believed to reflect the rapid changes in water content as well as myelination during brain development. The data will become publicly available as part of a normative pediatric MRI and clinical/behavioral database, thereby providing a basis for comparison in studies assessing normal brain development, and studies of deviations due to various neurological, neuropsychiatric, and developmental disorders. J. Magn. Reson. Imaging 2009;29:258–267. © 2009 Wiley‐Liss, Inc.
Added value of breathhold diffusion‐weighted MRI in detection of small hepatocellular carcinoma lesions compared with dynamic contrast‐enhanced MRI alone using receiver operating characteristic curve analysis
Authors: Xu Peng‐Ju , Yan Fu‐Hua , Wang Jian‐Hua , Lin Jiang , Ji Yuan
Published: January 2009

Purpose

To evaluate the added value of single‐breathhold diffusion‐weighted MRI (DWI) in detection of small hepatocellular carcinoma (HCC) lesions (≤2 cm) in patients with chronic liver disease, by comparing the detection sensitivity of combined DWI/conventional dynamic contrast‐enhanced (DCE)‐MRI to that of conventional DCE‐MRI alone.

Materials and Methods

A total of 37 patients with chronic liver diseases underwent abdominal MRI at 1.5T, including T1‐weighted imaging (T1WI), T2‐weighted imaging (T2WI), and 2D conventional DCE. For each patient study, axial DWI was performed with a single‐shot echo‐planar imaging (EPI) sequence using a modified sensitivity‐encoding (mSENSE) technique with b‐value of 500 seconds/mm2. A total of 20–24 slices were obtained during a 15–17‐second breathhold. Two observers independently interpreted the combined DWI/conventional DCE‐MRI images and the conventional DCE‐MRI images alone in random order. For all small HCC lesions, the diagnostic performance using each imaging set was evaluated by receiver operating characteristic (ROC) curve analysis. Sensitivity and positive predictive values were also calculated and analyzed.

Results

A total of 47 small HCCs were confirmed as final result. The area under the ROC curve (Az) of combined DWI/conventional DCE‐MRI images (observer 1, 0.922; observer 2, 0.918) were statistically higher than those of conventional DCE‐MRI alone (observer 1, 0.809; observer 2, 0.778) for all small HCC lesions (P < 0.01). The lesion detection sensitivities using the combined technique for both observers were significantly higher than those using conventional DCE‐MRI alone (P < 0.01). The sensitivity values for two observers using the combined technique were 97.87% and those using conventional DCE‐MRI alone were 85.11% to 82.98%. The positive predictive values for two observers using the combined imaging technique (97.87%) were slightly higher than those using conventional DCE‐MRI alone (92.86–93.02%), but there was no significant difference between the two imaging sets.

Conclusion

Combined use of breathhold DWI with conventional DCE‐MRI helped to provide higher sensitivities than conventional DCE‐MRI alone in the detection of small HCC lesions in patients with chronic liver disease. J. Magn. Reson. Imaging 2009;29:341–349. © 2009 Wiley‐Liss, Inc.
Pancreatic diffusion‐weighted imaging (DWI): Comparison between mass‐forming focal pancreatitis (FP), pancreatic cancer (PC), and normal pancreas
Authors: Fattahi Rana , Balci N. Cem , Perman William H. , Hsueh Eddy C. , Alkaade Samer , Havlioglu Necat , Burton Frank R.
Published: January 2009

Purpose

To compare diffusion‐weighted imaging (DWI) findings and the apparent diffusion coefficient (ADC) values of pancreatic cancer (PC), mass‐forming focal pancreatitis (FP), and the normal pancreas.

Materials and Methods

DWI (b = 0 and 600 seconds/mm2) findings of 14 patients with mass‐forming FP proven by histopathology and or clinical follow‐up, 10 patients with histopathologically‐proven PC, and 14 subjects with normal pancreatic exocrine function and normal imaging findings were retrospectively evaluated. ADC values of the masses, the remaining pancreas, and the normal pancreas were measured.

Results

On b = 600 seconds/mm2 DWI, mass‐forming FP was visually indistinguishable from the remaining pancreas whereas PC was hyperintense relative to the remaining pancreas. The mean ADC value of PC (1.46 ± 0.18 mm2/second) was significantly lower than the remaining pancreas (2.11 ± 0.32 × 10–3 mm2/second; P < 0.0001), mass‐forming FP (2.09 ± 0.18 × 10–3 mm2/second; P < 0.0001), and pancreatic gland in the control group (1.78 ± 0.07 × 10–3 mm2/second; P < 0.0005). There was no significant difference of ADC values between the mass‐forming focal pancreatitis and the remaining pancreas (2.03 ± 0.2 × 10–3 mm2/second; P > 0.05).

Conclusion

Differences on DWI may help to differentiate PC, mass‐forming FP, and normal pancreas from each other. J. Magn. Reson. Imaging 2009;29:350–356. © 2009 Wiley‐Liss, Inc.
On the inter‐instrument and inter‐laboratory transferability of a tandem mass spectral reference library: 1. Results of an Austrian multicenter study
Authors: Oberacher Herbert , Pavlic Marion , Libiseller Kathrin , Schubert Birthe , Sulyok Michael , Schuhmacher Rainer , Csaszar Edina , Köfeler Harald C.
Published: January 2009

The inter‐instrument and inter‐laboratory transferability of a tandem mass spectral reference library originally built on a quadrupole‐quadrupole‐time‐of‐flight instrument was examined. The library consisted of 3759 MS/MS spectra collected from 402 reference compounds applying several different collision‐energy values for fragmentation. In the course of the multicenter study, 22 test compounds were sent to three different laboratories, where 418 tandem mass spectra were acquired using four different instruments from two manufacturers. The study covered the following types of tandem mass spectrometers: quadrupole‐quadrupole‐time‐of‐flight, quadrupole‐quadrupole‐linear ion trap, quadrupole‐quadrupole‐quadrupole, and linear ion trap‐Fourier transform ion cyclotron resonance mass spectrometer. In each participating laboratory, optimized instrumental parameters were gathered solely from routinely applied workflows. No standardization procedure was applied to increase the inter‐instrument comparability of MS/MS spectra. The acquired tandem mass spectra were matched against the established reference library using a sophisticated matching algorithm, which is presented in detail in a companion paper. Correct answers, meaning that the correct compound was retrieved as top hit, were obtained in 98.1% of cases. For the remaining 1.9% of spectra, the correct compound was matched at second rank. The observed high percentage of correct assignments clearly suggests that the developed mass spectral library search approach is to a large extent platform independent. Copyright © 2009 John Wiley & Sons, Ltd.