bluuebunny/crossref_metadata_2025 huggingface dataset:
Interface Fermi Level Pinning at Contacts Between PEDOT: PSS and Molecular Organic Semiconductors
Authors: Peisert Heiko , Petr Andreas , Dunsch Lothar , Chassé Thomas , Knupfer Martin
Published: January 2007

Photoemission studies of interfaces between molecular organic semiconductors and the conducting polymer PEDOT: PSS [mixture of PEDOT (poly‐3,4‐ethylenedioxy‐thiophene) and PSS (polystyrenesulfonate)] demonstrate that it is impossible to control the charge injection barriers at such contacts by either a systematic change of the work function of the conducting polymer or that of the organic semiconductor. Instead, these interfaces are, in all cases, characterized by a charge transfer across the interface and a resulting Fermi level pinning. Thus interfacial charge barriers do not explain observed changes in device parameters as a function of the work function of the polymer electrode.
Fine‐needle aspiration biopsy of monophasic variant of spindle epithelial tumor with thymus‐like differentiation of the thyroid: Report of one case and review of the literature
Authors: Tong Guo‐Xia , Hamele‐Bena Diane , Wei Xiao‐Jun , O'Toole Kathleen
Published: January 2007

Spindle epithelial tumor with thymus‐like differentiation (SETTLE) is a rare biphasic tumor of the thyroid with ∼20 well‐documented cases reported in the English literature. Although a monophasic variant of SETTLE is conceivable, the majority of the reported cases were truly biphasic tumors. A minimal amount of epithelial component was present in the reported cases of so‐called spindle‐cell predominant SETTLE. Here, we report an apparently monophasic case of SETTLE in a 16‐yr‐old girl, in which no epithelial cells were identified in either fine‐needle aspiration biopsy (FNAB) or the subsequent hemithyroidectomy specimen. The FNAB smears were moderately cellular and composed of single and loosely grouped spindle cells with homogenous metachromatic material, which could be mistaken as amyloid, erroneously suggesting medullary thyroid carcinoma. The compact nodules of uniform spindle cells in histology sections raised the possibility of monophasic synovial sarcoma. The spindle cells stained positive for both cytokeratin and vimentin, but were negative for thyroglobulin and calcitonin as well as neuroendocrine markers, confirming the diagnosis of SETTLE. Diagn. Cytopathol. 2007;35:113–119. © 2007 Wiley‐Liss, Inc.
Secondary prostatic adenocarcinoma: A cytopathological study of 50 cases
Authors: Mai Kien T. , Roustan Delatour Nicolas L. D. , Assiri Ali , Al‐Maghrabi Hatim
Published: January 2007

Positive diagnosis of metastatic prostate adenocarcinoma (PAC) can be made by microscopic examination of the cytologic specimens and immunostaining for prostate‐specific antigen (PSA) and prostate acid phosphatase (PAP). Immunohistochemical markers have been known to display negative, weak, or focal staining in poorly differentiated PAC and in patients with prior hormonal and/or radiation therapy. The purpose of this study is to characterize the cytopathology of metastatic PAC as it has not been documented in large series. Fifty cases of metastatic PAC with cytological specimens consisting of 41 fine‐needle aspiration biopsies (FNAB), 6 pleural fluid aspirates, and 3 catheterized urine samples were reviewed and correlated with the surgical specimens and the clinical charts. Immunostaining for PSA, PAP, cytokeratin AE1/3, cytokeratin 7 (CK7), cytokeratin 20 (CK20), vimentin, and carcinoembryonic antigen (CEA) was done. Mean patient age was 77 ± 8 yr; serum PSA, 4.1 ± 2.3; and primary PAC Gleason score, 8.1 ± 1.5. Cytologically, the specimens consisted of cell clusters or cell sheets with overlapping uniform hyperchromatic nuclei with or without nucleoli. Twelve cases were not reactive to PSA and PAP and 44 cases displayed negative immunoreactivity to both CK7 and CK20. Carcinoid‐like lesions and small cell carcinomas were seen in 4 cases and were misdiagnosed as nonprostatic origin based on the following features: negative immunoreactivity to PSA and PAP with or without positive reactivity to CEA, and different histopathological features when compared with the primary PAC. In addition to the frequency of high‐grade PAC, awareness of the negative immunoreactivity to PSA and PAP, the discrepancy in the histopathological patterns between the primary and secondary tumors, especially the frequent neuroendocrine differentiation, are helpful features for the diagnosis of metastases of prostatic origin. Diagn. Cytopathol. 2007;35:91–95. © 2007 Wiley‐Liss, Inc.
Correlation of cytologic examination with ELISA assays for hyaluronan and soluble CD44v6 levels in evaluation of effusions
Authors: Afify Alaa , Lynne Lin‐Chang , Howell Lydia
Published: January 2007

Hyaluronan (HA) and its major cell surface receptor, CD44, play an important role in tumor growth, proliferation, neovascularization, and invasion. CD44 is an integral transmembrane protein and exists in standard form (CD44s), as well as a myriad of CD44 variants isoforms (CD44v1–v10). Functional fragments of the CD44 can be released from the cell membrane by proteolytic cleavage of extracellular domain producing soluble CD44. Although studies have proposed the use of serum HA and soluble CD44, specifically soluble CD44v6 (sCD44v6) levels, as a tumor markers, its diagnostic utility in body fluid samples has not been clearly established. The purpose of this study was to correlate HA and sCD44v6 levels in effusions with the cytology diagnosis and to assess their usefulness in differentiating between malignant and nonmalignant effusions. In this retrospective study we evaluated HA and sCD44v6 contents in 20 effusions from cytologically positive samples and 10 effusions from cytologically negative samples. Corresponding cytopathology slides were reviewed to confirm the diagnoses. Malignant effusions included 18 cases of metastatic adenocarcinomas (9 ovarian, 3 breast, 3 pulmonary, 3 adenocarcinoma of unknown primary) and 2 cases of lymphomas. The level of HA and sCD44v6 were measured using a sandwich enzyme‐linked immunoadsorbent assay. For HA, we used hyaluronic acid quantitative test kit (Corgenix, Denver, CO) and for sCD44v6 we used Human sCD44v6 Instant ELISA (Bender MedSystems, Vienna, Austria). HA concentrations (μg/mL) and sCD44v6 concentrations (ng/mL) were calculated and correlated with clinical data as well as cytodiagnosis. The mean concentration of HA (22.42 ± 5 μg/mL) and sCD44v6 (70 ± 42 ng/mL) in the cytologically positive samples was significantly higher than those in the cytologically negative samples for HA (5.5 ± 5 μg/mL, P < 0.01) and sCD44V6 (17 ± 10 ng/mL, P < 0.01). Using benign effusions as control and the upper limits of its mean levels for HA (10.5 μg/mL) as the positive boundary value, HA levels exceeded the boundary line in 17 out of 20 malignant effusions and 2 out of 10 benign effusions. Meanwhile, sCD44v6 exceeded the boundary line (27 ng/mL) in 18 out of 20 malignant effusions and 3 out of 10 benign effusions. The calculated sensitivity and specificity of this assay to the diagnosis of malignant effusions were 85 and 80% for HA and 90 and 70% for CD44v6, respectively. We conclude that the HA and sCD44v6 levels in body fluids correlate with the cytology diagnosis and could be used as an ancillary study in cytology to differentiate nonmalignant from malignant effusions. Diagn. Cytopathol. 2007;35:105–110. © 2007 Wiley‐Liss, Inc.
Kallikrein 4 is expressed in malignant mesothelioma—Further evidence for the histogenetic link between mesothelial and epithelial cells
Authors: Davidson Ben , Xi Zhijun , Saatcioglu Fahri
Published: January 2007

The objective of this study was to analyze Kallikrein 4 protein (hK4) expression in effusions and solid tumors of patients diagnosed with malignant mesothelioma (MM) and compare hK4 expression in MM with that in breast and ovarian adenocarcinomas. Sections from 65 MM (21 effusions, 44 solid tumors) and 63 breast carcinomas (28 effusions, 35 solid tumors) were stained for hK4 using immunohistochemistry. Results were compared with our previously published data for 284 ovarian carcinomas (181 effusions, 103 solid tumors). Expression of hK4 was detected in 26/65 (40%) MM and 52/63 (83%) breast carcinomas. Ovarian carcinoma showed staining values that were comparable to those in breast carcinoma (expression of hK4 in 144/181; 80% effusions and 85/103; 83% solid tumors). As opposed to our previous findings in ovarian carcinoma, hK4 expression was higher in solid tumors when compared with to effusions in both MM (P = 0.013) and breast carcinoma (P = 0.002). Comparative analysis of the three tumor types showed significantly higher expression in ovarian and breast adenocarcinomas when compared with MM (P < 0.001). In conclusion, hK4 is frequently expressed in MM, with higher levels detected in solid tumors, although its expression is more limited than in gynecological adenocarcinomas. The presence of hK4 in MM, a non‐hormonally regulated tumor, provides further support to the histogenetic link between mesothelial and epithelial cells. Diagn. Cytopathol. 2007;35:80–84. © 2007 Wiley‐Liss, Inc.
Fine‐needle aspiration cytology of basal cell adenoma of the parotid gland: Characteristic cytological features and diagnostic pitfalls
Authors: Kawahara Akihiko , Harada Hiroshi , Akiba Jun , Yokoyama Toshiro , Kage Masayoshi
Published: January 2007

We retrospectively studied the cytological features of aspiration cytology in 12 cases of basal cell adenoma (BCA) and 5 cases mistakenly diagnosed as BCA. On macroscopic findings, the 12 cases of BCA included 7 cases of solid type and 5 cases of cystic type. The characteristic cytological features of solid type BCA were three‐dimensional clusters in 71%, sharp‐angle small clusters in 86%, basement membrane‐ like material in 71%, and cell crush in 86%. In contrast, 3 of the 5 cystic type BCA cases showed inadequate cellular components or no basaloid tumor cells, and the cytological diagnosis of BCA could not be determined. In the 5 cases misdiagnosed as BCA, there were 2 cases of pleomorphic adenoma, 2 cases of benign lymphoepithelial cyst, and 1 case of basal cell adenocarcinoma. Accurate differential cytological diagnosis of BCA is relatively easy to determine the solid type BCA, but is more difficult for cystic type BCA. Diagn. Cytopathol. 2007;35:85–90. © 2007 Wiley‐Liss, Inc.
A three‐armed trial of the ThinPrep Imaging System
Authors: Roberts Jennifer M. , Thurloe Julia K. , Bowditch Ron C. , Hyne Suzanne G. , Greenberg Merle , Clarke Joanne M. , Biro Clare
Published: January 2007

We compared the performance of the ThinPrep (TP) Imaging System (TIS) with manual reading of TP slides (TPM) and with manual reading of the paired conventional Pap smear (PS) in terms of sensitivity for and positive predictive value (PPV) of high‐grade disease and productivity.

The study consisted of 11,416 routine PS and paired TP slides as well as 103 confirmed abnormal TP slides.

In terms of sensitivity for the detection of biopsy‐confirmed high‐grade disease, overall there was no statistically significant difference between TIS‐screened TP (TPI) and TPM (81.1% vs. 86.8%). For the routine cases, TPI was significantly more sensitive than PS (73.4% vs. 57.8%).

In terms of PPVs for the cytologic prediction of high‐grade disease, there was no statistically, significant difference among TPI, TPM, and PS (75.6%, 73.9%, and 84.6%). For cytologic reports of possible high‐grade disease, the PPVs were equivalent for TPI (45.0%) and TPM (37.0%) and there was no significant difference in PPVs between TPI and PS (61.3%). For TP slides, TIS screening showed a 27% productivity gain when compared with manual screening and a 54% productivity gain when compared with manual screening of PS slides.

Use of TIS showed productivity benefits when compared with TPM and both productivity and sensitivity benefits over use of PS. Diagn. Cytopathol. 2007;35:96–102. © 2007 Wiley‐Liss, Inc.
Visualization of outflow tract development in the absence of Tbx1 using an FgF10 enhancer trap transgene
Authors: Kelly Robert G. , Papaioannou Virginia E.
Published: January 2007

Tbx1, the major gene underlying del22q11.2 or DiGeorge syndrome in humans, is required for normal development and septation of the cardiac outflow tract. The fibroblast growth factor 10 gene (Fgf10) and an Fgf10 enhancer trap transgene are expressed in outflow tract myocardial progenitor cells of the anterior heart field. To visualize outflow tract development in the absence of Tbx1, we have analyzed the expression profile of the Fgf10 enhancer trap transgene during outflow tract development in Tbx1−/− embryos. Transgene expression confirms hypoplasia of the distal outflow tract in the absence of Tbx1, and altered expression in pharyngeal mesoderm reveals loss of specific bilateral subpopulations of outflow tract progenitor cells and disruption of the posterior boundary of the anterior heart field. Our results support the conclusion that Tbx1 controls deployment of Fgf10‐expressing progenitor cells during heart tube extension. Furthermore, although normal Fgf10 levels are dependent on Tbx1, loss of Fgf10 alleles does not significantly modify the cardiac phenotype of Tbx1 heterozygous or homozygous mutant embryos. Developmental Dynamics 236:821–828, 2007. © 2007 Wiley‐Liss, Inc.
Electrocatalytic Reduction of HNO2 by a Silicomolybdate Polyanion: A Differential Electrochemical Mass Spectrometry Study
Authors: Debiemme‐Chouvy Catherine , Cachet Hubert , Folcher Guy , Deslouis Claude
Published: January 2007

Electrocatalytic activities towards the reduction of important analytes such as nitrite, bromate, chlorate and hydrogen peroxide have been demonstrated for numerous heteropolyanions (HPAs). In this paper, the behavior of a Keggin‐type HPA, SiMo12O, on the one hand in solution and on the other hand immobilized in a conducting polymer, polypyrrole (PPy), in the presence of nitrous acid (HNO2) is examined. It is shown that the PPy films codoped with SiMo12O and HSO ions could be used as sensitive part of an amperometric sensor even if the response is limited by HNO2 diffusion into the PPy film. Differential electrochemical mass spectrometry (DEMS) was used to determine the gas formed during nitrous acid reduction by H2SiMo12O. Under an applied cathodic potential, when both HNO2 and SiMo12O are present in the medium, NO gas is produced whereas, when SiMo12O ions are immobilized in a PPy film, N2O evolves and the NO concentration, notably due to the disproportionation of HNO2, decreases.
On‐Chip Determination of Dopamine Exocytosis Using Mercaptopropionic Acid Modified Microelectrodes
Authors: Spégel Christer , Heiskanen Arto , Acklid Jenny , Wolff Anders , Taboryski Rafael , Emnéus Jenny , Ruzgas Tautgirdas
Published: January 2007

Gold and platinum, which often are used for thin film metallization, are not suitable for the measurement of dopamine (DA), since the oxidation product of DA forms a non‐conducting polymer on the electrode surface. In this work several thiols were screened for their ability to prevent this polymerization. It was found that mercaptopropionic acid (MPA) decreased the rate of DA polymerization. MPA, possessing a weak acidic functionality, had the greatest effect on the DA electrochemistry by decreasing electrode passivation, as well as improving reversibility and sensitivity. Modifications of microchip electrodes with MPA did not only improve DA electrochemistry but also significantly increased the storage stability of the transducers. The microchips were ultimately used to detect K+ stimulated quantal release of DA from PC12 cells.
Chloride‐Selective Electrodes with Poly(n‐butyl acrylate) Based Membranes
Authors: Lyczewska Monika , Wojciechowski Marcin , Bulska Ewa , Hall Elizabeth A. H. , Maksymiuk Krzysztof , Michalska Agata
Published: January 2007

Chloride‐selective electrodes with tridodecylmethylammonium chloride ion‐exchanger and poly(n‐butyl acrylate) membrane were prepared. A significant advantage of these electrodes, compared to poly(vinyl chloride) based membranes is the lack of plasticizer which can contaminate samples due to leaching during long term measurements. Analytical parameters: linear response range, slope of dependence and detection limit were comparable to those characterizing poly(vinyl chloride) membrane sensors. However, the analytical characteristic of poly(n‐butyl acrylate) membrane sensors was largely independent of the ion‐exchanger content in the membrane and of the galvanostatic polarization applied. The selectivity pattern obtained showed that interferences for highly lipophilic anions were slightly more pronounced than for PVC membrane counterparts. Laser ablation with inductively coupled plasma mass spectrometry (LA‐ICP‐MS) studies of poly(n‐butyl acrylate) membranes free from tridodecylmethylammonium chloride revealed a relatively high background content of chlorine – comparable with the amount purposely introduced to the membrane containing ion‐exchanger. These impurities, regardless their chemical state, are affecting the response of the sensors obtained. The LA‐ICP‐MS data showed that while contact with Cl− containing solutions did not induce the coextraction of cations, salicylate interference is accompanied by high uptake of solution cations.
Determination of Labile Cadmium Using a Screen‐Printed Electrode Modified by a Microwell
Authors: Parat Corinne , Authier Laurent , Betelu Stéphanie , Petrucciani Nathalie , Potin‐Gautier Martine
Published: January 2007

A microwell has been deposited on the working surface of a screen‐printed electrode in order to reduce the sample volume from 10 mL to 200 μL for trace metal analysis in square wave anodic stripping voltammetry. It has been shown that the sample volume reduction did not affect the sensitivity. A detection limit of 2×10−9 mol L−1 of Cd was established with these modified sensors for a preconcentration time of 60 s without stirring. Also it has been shown that pH ranging from 4 to 7 did not affect the sensor sensitivity. These modified sensors were able to run at neutral pH in real samples, such as soil solutions, containing higher organic carbon concentration and thus offered a first and rapid approach of Cd speciation.
Constant‐Distance Mode Scanning Potentiometry. High Resolution pH Measurements in Three‐Dimensions
Authors: Etienne Mathieu , Dierkes Paul , Erichsen Thomas , Schuhmann Wolfgang , Fritsch Ingrid
Published: January 2007

A very small liquid‐membrane based pH probe (less than 500 nm diameter) has been implemented in scanning electrochemical microscopy (SECM) equipped with a nonoptical shear force‐based distance control. This constant‐distance mode pH microscopy was tested over a complex microcavity (50 μm diameter, 8 μm deep) possessing three individually‐addressable gold electrodes: a microdisk at the bottom, a microcrescent ring 4 μm away and along the wall, and a planar macroelectrode around the rim at the top. All the experiments were performed in a buffer of pH 6.22. The pH inside the microcavity was modified locally by applying negative potential (reduction of O2 and H2O to produce OH−) either at the ring or disk electrodes. The shear force‐sensitive signal permitted the precise determination of the tip‐to‐sample distance. Moreover, operating in constant‐distance mode, the tip‐to‐sample distance was kept constant (less than 200 nm) while scanning the electrode over the sample. The simultaneous collection of both topographic and potentiometric information allowed a better understanding of the complex electrochemical processes occurring within the microcavity. Since potentiometry is not disturbing diffusion profiles in front of active electrodes constant‐distance scanning potentiometry can be applied for the visualization of processes occurring in close proximity to electrode surfaces. This is especially important for the elucidation of properties of redox recycling systems often applied in amplified electrochemical assays.
Erodibility of soil and organic matter: independence of organic matter resistance to interrill erosion
Authors: Kuhn Nikolaus J.
Published: January 2007

The enrichment of organic matter in interrill sediment is well documented; however, the respective roles of soil organic matter (SOM) and interrill erosion processes for the enrichment are unclear. In this study, organic matter content of sediment generated on two silts with almost identical textures, but different organic matter contents and aggregations, was tested. Artificial rainfall was applied to the soils in wet, dry and crusted initial conditions to determine the effects of soil moisture and rainfall and drying history on organic matter enrichment in interrill sediment. While erosional response of the soils varied significantly, organic matter enrichment of sediment was not sensitive to initial soil conditions. However, enrichment was higher on the silt with a lower organic matter content and lower interrill erodibility. The results show that enrichment of organic matter in interrill sediment is not directly related to either SOM content or soil interrill erodibility, but is dominated by interrill erosion processes. As a consequence of the complex interaction between soil, organic matter and interrill erosion processes, erodibility of organic matter should be treated as a separate variable in erosion models. Further research on aggregate breakdown, in particular the content and fate of the organic matter in the soil fragments, is required. Copyright © 2007 John Wiley & Sons, Ltd.
Contrasting effects of mitogenic growth factors on myelination in neuron–oligodendrocyte co‐cultures
Authors: Wang Zhen , Colognato Holly , ffrench‐Constant Charles
Published: January 2007

Mitogenic growth factors play an important role in the initial stages of oligodendrocyte development, but their roles in the process of myelination itself remain less well defined. In order to study directly the effects of different growth factors on myelination, we used a purified in vitro co‐culture system with dorsal root ganglion neurons and oligodendrocytes. Extensive myelination had occurred in these cultures 14 days after oligodendrocyte precursors (OPCs) were added, with the relationship between neurite density and the percentage of oligodendrocytes forming myelin sheaths providing a robust and straightforward means of quantifying myelination. Addition of soluble neuregulin (Nrg1), a mitogen for oligodendroglial cells that also provides an axonal signal implicated in oligodendrocyte survival, increased myelination. Conversely, the OPC mitogens FGF‐2 and PDGF inhibited myelination. The inhibitory effect of these mitogens was reversible, as inhibition of PDGF allowed myelination to proceed. Taken together, these data indicate that different mitogenic growth factors can regulate myelination by oligodendrocytes in addition to their well‐described effects on earlier stages of oligodendroglial development. Moreover, the results highlight important differences between the growth factors. © 2007 Wiley‐Liss, Inc.
Neurofibromin‐deficient Schwann cells have increased lysophosphatidic acid dependent survival and migration—implications for increased neurofibroma formation during pregnancy
Authors: Nebesio Todd D. , Ming Wenyu , Chen Shi , Clegg Travis , Yuan Jin , Yang Yanzhu , Estwick Selina A. , Li Yan , Li Xiaohong , Hingtgen Cynthia M. , Yang Feng‐Chun
Published: January 2007

Neurofibromas are the clinical hallmark of neurofibromatosis Type 1 (NF1), a genetic disorder caused by mutations of the NF1 tumor suppressor gene, which encodes neurofibromin that functions as a GTPase activating protein (GAP) for Ras. During pregnancy, up to 50% of existing neurofibromas enlarge and as many as 60% of new neurofibromas appear for the first time. Lysophosphatidic acid (LPA) is a prototypic lysophospholipid that modulates cell migration and survival of Schwann cells (SCs) and is made in increasing concentrations throughout pregnancy. We addressed the influence of LPA on the biochemical and cellular functions of SCs with a homozygous mutation of the murine homologue of the NF1 gene (Nf1−/−). LPA promoted F‐actin polymerization and increased migration and survival of Nf1−/− SCs as compared to wild type (WT) SCs. Furthermore, LPA induced a higher level of Ras‐GTP and Akt phosphorylation in Nf1−/− SCs as compared to WT cells. Pharmacologic inhibition or siRNA for the p85β regulatory subunit of Class I A PI3‐K significantly reduced LPA‐induced Schwann cell survival and migration. Introduction of NF1‐GRD reconstitution was sufficient to normalize the LPA‐mediated motility of Nf1−/− SCs. As LPA modulates excessive cell survival and motility of Nf1−/− SCs, which are the tumorigenic cells in NF1, targeting PI3‐K may be a potential therapeutic approach in diminishing the development and progression of neurofibromas in pregnant women with NF1. © 2007 Wiley‐Liss, Inc.
Do pre‐irradiation dental extractions reduce the risk of osteoradionecrosis of the mandible?
Authors: Chang Daniel T. , Sandow Pamela R. , Morris Christopher G. , Hollander Rachel , Scarborough Lauren , Amdur Robert J. , Mendenhall William M.
Published: January 2007

Background.

This study was done to determine if pre‐radiotherapy (pre‐RT) dental extractions reduce the risk of osteoradionecrosis (ORN).

Methods.

Between 1987 and 2004, 413 patients with oropharyngeal carcinomas were treated with definitive RT at the University of Florida. Dentate patients underwent pretreatment dental evaluation. Teeth in the RT field were usually extracted if thought to have poor long‐term prognosis from dental disease. The endpoint was ≥grade 2 ORN using a modified staging system. Patients were excluded for local recurrence, additional RT above the clavicles, or head and neck surgery besides neck dissection.

Results.

ORN rates were as follows: edentulous, <1%; teeth in‐field with pre‐RT extractions, 15%; and teeth in‐field without pre‐RT extractions, 9%. Patients with poor in‐field teeth and pre‐RT extractions had a higher 5‐year incidence of ORN than those who did not have pre‐RT extractions (16% vs 6%, p = .48). Likewise, for those with in‐field teeth in good condition and pre‐RT extractions, the 5‐year ORN incidence was higher than for those who did not undergo extractions (15% vs 2%, p = .42). Multivariate analysis revealed increased ORN risk with doses of >70 Gy, once‐daily fractionation, or brachytherapy.

Conclusion.

Pre‐RT extractions do not appear to reduce the risk of ORN. © 2007 Wiley Periodicals, Inc. Head Neck, 2007
Management of frey syndrome
Authors: de Bree Remco , van der Waal Isaäc , Leemans C. René
Published: January 2007

Almost all patients who undergo parotidectomy will to some extent develop Frey syndrome (auriculotemporal syndrome or gustatory sweating) after surgery, because of aberrant regeneration of cut parasympathetic fibers between otic ganglion and subcutaneous vessels. However, only the minority of these patients needs treatment. The syndrome consists of gustatory sweating, flushing, and warming over the preauricular and temporal areas. Thick skin flap and partial superficial parotidectomy are the most important techniques to minimize the risk of developing symptomatic Frey syndrome. Intracutaneous injection of botulinum toxin A is an effective, long‐lasting, and well‐tolerated treatment of Frey syndrome. If recurrence occurs, the treatment can be repeated. © 2007 Wiley Periodicals, Inc. Head Neck, 2007
Current topics in the epidemiology of oral cavity and oropharyngeal cancers
Authors: Gillison Maura L.
Published: January 2007

Oral cancer incidence rates rose dramatically during the twentieth century in the United States and Europe, especially among individuals under the age of 60 years. Although influenced by age, sex, and country of origin, incidence trends were most strongly affected by elevated risk among individuals born after approximately 1915. This cohort effect was indicative of strong behavioral influences on oral cancer risk. In this article, associations between oral cancer risk and established behavioral risk factors including alcohol and tobacco use are reviewed. Additionally, possible associations between oral cancer risk and oral hygiene, diet, nutritional status, and sexual behavior as well as the influence of genetic factors on oral cancer risk are considered. Special emphasis is placed on evaluating possible risk differences in individuals above and below the age of 45 and in users and nonusers of alcohol and tobacco. © 2007 Wiley Periodicals, Inc. Head Neck 29, 2007
Cutaneous head and neck squamous cell carcinoma metastatic to parotid and cervical lymph nodes
Authors: Veness Michael J. , Porceddu Sandro , Palme Carsten E. , Morgan Gary J.
Published: January 2007

Nonmelanoma skin cancers occur at an epidemic rate in Australia and are increasing in incidence worldwide. In most patients, local treatment is curative. However, a subset of patients will be diagnosed with a high‐risk cutaneous squamous cell carcinoma (SCC) and are defined as patients at increased risk of developing metastases to regional lymph nodes. Patients with high‐risk SCC may be identified based on primary lesion and patient factors. Most cutaneous SCC arises on the sun‐exposed head and neck. The parotid and upper cervical nodes are common sites for the development of metastases arising from ear, anterior scalp, temple/forehead, or scalp SCC. The mortality and morbidity associated with high‐risk cutaneous SCC is usually a consequence of uncontrolled metastatic nodal disease and, to a lesser extent, distant metastases. Patients with operable nodal disease have traditionally been recommended for surgery. The efficacy of adjuvant radiotherapy has previously been questioned based on weak evidence in the early literature. Recent evidence from larger studies has, however, strengthened the case for adjuvant radiotherapy as a means to improve locoregional control and survival. Despite this, many patients still experience relapse and die. Research aimed at improving outcome such as a randomized trial incorporating the addition of chemotherapy to adjuvant radiotherapy is currently in progress in Australia and New Zealand. Ongoing research also includes the development of a proposed new staging system and investigating the role of molecular factors such as the epidermal growth factor receptor. © 2007 Wiley Periodicals, Inc. Head Neck, 2007
Effects of radiotherapy with or without chemotherapy on tongue strength and swallowing in patients with oral cancer
Authors: Lazarus Cathy , Logemann Jeri A. , Pauloski Barbara Roa , Rademaker Alfred W. , Helenowski Irene B. , Vonesh Edward F. , MacCracken Ellen , Mittal Bharat B. , Vokes Everett E. , Haraf Daniel J.
Published: January 2007

Background.

Oral tongue strength and swallowing ability are reduced in patients treated with chemoradiotherapy for oral and oropharyngeal cancer.

Methods.

Patients with oral or oropharyngeal cancer treated with high‐dose chemoradiotherapy underwent tongue strength, swallowing, and dietary assessments at pretreatment and 1, 3, 6, and 12 months posttreatment. Tongue strength was assessed using the Iowa Oral Performance Instrument (IOPI). Oral and pharyngeal residue was evaluated utilizing videofluoroscopy.

Results.

Mean maximum tongue strength dropped a nonsignificant amount immediately after treatment, and then increased significantly at 6‐ and 12‐months posttreatment completion. Analyses were adjusted for patient dropout. Tongue strength was not significantly correlated with swallow observations of percentage oral and pharyngeal residue. Ability to eat various diet consistencies was reduced after treatment but improved over time at a rate similar to changes in oral intake and type of diet.

Conclusions.

Parallel but not significant changes in oral intake, diet, and tongue strength in the first year post chemoradiation therapy need further study in a larger population. © 2007 Wiley Periodicals, Inc. Head Neck, 2007
Phosphocholine as a biomarker of breast cancer: Molecular and biochemical studies
Authors: Eliyahu Galit , Kreizman Tamar , Degani Hadassa
Published: January 2007

The discovery of metabolic and molecular markers that help improving the detection and diagnosis of breast cancer is an important goal to be achieved. A high composite‐choline signal in magnetic resonance spectra of breast lesions has been demonstrated to improve the accuracy of breast cancer diagnosis. In the present study we revealed the principal molecular and biochemical steps associated with the induction of choline metabolism and phosphocholine accumulation in human breast cancer cell‐lines in comparison with normal human mammary epithelial cells. We found upregulation of the expression levels of specific choline transporters: organic cation transporter‐2 and choline high affinity transporter‐1, as well as of the enzyme choline kinase α in the cancerous cells in comparison with that in the normal mammary epithelial cells. The expression levels of choline transporter like‐1, organic cation transporter‐1 and choline kinase β were similar in normal and cancerous cells. We further showed that choline transport rates and choline kinase activity indeed increased by several fold in the cancer cells leading to the elevation of phosphocholine. The results strongly suggest that phosphocholine can serve as a biomarker of breast cancer reflecting upregulation of specific choline transporters and choline kinase genes. © 2007 Wiley‐Liss, Inc.
Gene expression profiling of esophageal cancer: Comparative analysis of Barrett's esophagus, adenocarcinoma, and squamous cell carcinoma
Authors: Greenawalt Danielle M. , Duong Cuong , Smyth Gordon K. , Ciavarella Marianne L. , Thompson Natalie J. , Tiang Thomas , Murray William K. , Thomas Robert J.S. , Phillips Wayne A.
Published: January 2007

Esophageal cancer is a particularly aggressive tumor with poor prognosis, however, our current knowledge of the genes and pathways involved in tumorigenesis of the esophagus are limited. To obtain insight into the molecular processes underlying tumorigenesis of the esophagus, we have used cDNA microarrays to compare the gene expression profiles of 128 tissue samples representing the major histological subtypes of esophageal cancer (squamous cell carcinoma and adenocarcinoma (ADC)) as well as Barrett's esophagus (BE), the precursor lesion to ADC, and normal esophageal epithelium. Linear discriminant analysis and unsupervised hierarchical clustering show the separation of samples into 4 distinct groups consistent with their histological subtype. Differentially expressed genes were identified between each of the tissue types. Comparison of gene ontologies and gene expression profiles identified gene profiles specific to esophageal cancer, as well as BE. “Esophageal cancer clusters,” representing proliferation, immune response, and extracellular matrix genes were identified, as well as digestion, hydrolase, and transcription factor clusters specific to the columnar phenotype observed during BE and esophageal ADC. These clusters provide valuable insight into the molecular and functional differences between normal esophageal epithelium, BE, and the 2 histologically distinct forms of esophageal cancers. Our thorough, unbiased analysis provides a rich source of data for further studies into the molecular basis of tumorigenesis of the esophagus, as well as identification of potential biomarkers for early detection of progression. © 2007 Wiley‐Liss, Inc.
Development of a new calcium sulphate‐based composite using alginate and chemically modified chitosan for bone regeneration
Authors: Gomez d'Ayala Giovanna , De Rosa Alfredo , Laurienzo Paola , Malinconico Mario
Published: January 2007

In this work we developed a novel calcium sulphate‐based composite in which the hemihydrate calcium sulphate (CHS) can be encapsulated in a polymeric biodegradable and biocompatible matrix, in order to retain the structural integrity and decrease the bioresorption rate in bone regeneration applications. Two polymers were employed to realize this system: chitosan (Ch) and sodium alginate (Alg), both already widely used in biotechnological and biomedical applications. Chitosan was modified in order to obtain a water soluble polymer, the N‐succinylchitosan (sCh). The reaction was performed with succinic anhydride in presence of pyridine and confirmed by FT‐IR and NMR analyses. Finely ground Alg and sCh powders were mixed in different compositions with CHS and by adding water to the powder mixture it was obtained a mouldable paste that sets in few hours. Thermogravimetric analyses coupled with solvent extraction performed on the composite proved the alginate crosslinking in the presence of CHS. Mechanical studies carried out on composites of different compositions demonstrated that the blend of the two polymeric components causes a substantial synergistic reinforcement of composites. The presence of carboxylic groups on sCh chain in addition to those of alginate could enhance the chelating power of polysaccharide mixture. The results obtained with morphological analyses (SEM) further confirmed the hypotesis of the synergistic effect between alginate and N‐succinylchitosan in presence of calcium sulphate. In vitro cytotoxicity tests proved that the developed system was not cytotoxic. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Histological and mechanical evaluation of self‐setting calcium phosphate cements in a sheep vertebral bone void model
Authors: Kobayashi Naomi , Ong Kevin , Villarraga Marta , Schwardt Jeffrey , Wenz Robert , Togawa Daisuke , Fujishiro Takaaki , Turner A. Simon , Seim Howard B. , Bauer Thomas W.
Published: January 2007

We investigated the histological and compressive properties of three different calcium phosphate cements (CPCs) using a sheep vertebral bone void model. One of the CPCs contained barium sulfate to enhance its radiopacity. Bone voids were surgically created in the lumbar region of 23 ovine spines—L3, L4, and L5 (n = 69 total vertebral bodies)—and the voids were filled with one of the three CPCs. A fourth group consisted of whole intact vertebrae. Histologic evaluation was performed for 30 of the 69 vertebrae 2 or 4 months after surgery along with radiographic evaluation. Compressive testing was performed on 39 vertebrae 4 months after surgery along with micro‐CT analysis. All three CPCs were biocompatible and extremely osteoconductive. Osteoclasts associated with adjacent bone formation suggest that each cement can undergo slow resorption and replacement by bone and bone marrow. Compressive testing did not reveal a significant difference in the ultimate strength, ultimate strain, and structural modulus, among the three CPCs and intact whole vertebrae. Micro‐CT analysis revealed good osseointegration between all three CPCs and adjacent bone. The barium sulfate did not affect the CPCs biocompatibility or mechanical properties. These results suggest that CPC might be a good alternative to polymethylmethacrylate for selected indications. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Relationship between bone ingrowth, mineral apposition rate, and osteoblast activity
Authors: Bloebaum R.D. , Willie B.M. , Mitchell B.S. , Hofmann A.A.
Published: January 2007

To better understand skeletal attachment of porous coated total hip and knee implants over time, this study investigated the dynamics of osteoblast populations at the interface of porous coated implants in a weight‐bearing ovine model. The relationship between cancellous bone ingrowth, mineral apposition rate (MAR), and osteoblast activity indicators such as osteoblast area, relative osteoblast number, osteoid width, and osteoid area (O.Ar.) were investigated. The data demonstrated that the percent O.Ar. was a marginally significant predictor of bone ingrowth and MAR over time, suggesting that the amount of osteoid present influenced bone ingrowth and MAR in the porous coated implants. The data also demonstrated that all osteoblast activity indicators were significantly greater in the porous coated region compared to the host bone region, while controlling for in situ time (p < 0.05). This may have been due to the trauma of implantation or the influence of the implant load on the bone tissue promoting a regional acceleratory phenomenon. The localized response suggests that specific therapies may be developed to affect the physiology of osteoblasts at the interface of implants, which may allow for improve skeletal attachment of biomaterials and clinical outcomes of cementless joint replacements. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Vascular endothelial growth factor and dexamethasone release from nonfouling sensor coatings affect the foreign body response
Authors: Norton L.W. , Koschwanez H.E. , Wisniewski N.A. , Klitzman B. , Reichert W.M.
Published: January 2007

Vascular endothelial growth factor (VEGF) and dexamethasone (DX) release from hydrogel coatings were examined as a means to modify tissue inflammation and induce angiogenesis. Antibiofouling hydrogels for implantable glucose sensor coatings were prepared from 2‐hydroxyethyl methacrylate, N‐vinyl pyrrolidinone, and polyethylene glycol. Microdialysis sampling was used to test the effect of the hydrogel coating on glucose recovery. VEGF‐releasing hydrogel‐coated fibers increased vascularity and inflammation in the surrounding tissue after 2 weeks of implantation compared to hydrogel‐coated fibers. DX‐releasing hydrogel‐coated fibers reduced inflammation compared to hydrogel‐coated fibers and had reduced capsule vascularity compared to VEGF‐releasing hydrogel‐coated fibers. Hydrogels that released both VEGF and DX simultaneously also showed reduced inflammation at 2 weeks implantation; however, no enhanced vessel formation was observed indicating that the DX diminished the VEGF effect. At 6 weeks, there were no detectable differences between drug‐releasing hydrogel‐coated fibers and control fibers. From this study, hydrogel drug release affected initial events of the foreign body response with DX inhibiting VEGF, but once the drug depot was exhausted these effects disappeared. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Novel thermosensitive polymeric micelles for docetaxel delivery
Authors: Yang Mi , Ding Yitao , Zhang Leyang , Qian Xiaoping , Jiang Xiqun , Liu Baorui
Published: January 2007

Targeted delivery of antitumor drugs triggered by hyperthermia has significant advantages in clinical applications, since it is easy to implement and side effects are reduced. To release drugs site‐specifically upon local heating often requires the drugs to be loaded into a thermosensitive polymer matrix with a low critical solution temperature (LCST) between 37 and 42°C. However, the LCSTs of most thermosensitive materials were below 37°C, which limits their application in clinic because they would precipitate once injected into human body and lost thermal targeting function. Herein, we prepared a novel thermosensitive copolymer (poly(N‐isopropylacrylamide‐co‐acrylamide)‐b‐poly (DL‐lactide)) that exhibits no obvious physical change up to 41°C when heated. Docetaxel loaded micelles made of such thermosensitive polymer were prepared by dialysis method and the maximum loading content was found to be up to 27%. The physical properties, such as structure, morphology, and size distribution of the micelles with and without docetaxel were investigated by NMR, X‐ray diffraction, dynamic light scattering, atomic force microscopy, etc. The efficacy of this drug delivery system was also evaluated by examining the proliferation inhibiting activity against different cell linesin vitro. After hyperthermia, the cytotoxicity of docetaxel‐loaded micelles increased prominently. Our results demonstrated that this copolymer could be an ideal candidate for thermal targeted antitumor drug delivery. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Combination of platelet‐rich plasma with polycaprolactone‐tricalcium phosphate scaffolds for segmental bone defect repair
Authors: Rai Bina , Oest Megan E. , Dupont Ken M. , Ho Kee H. , Teoh Swee H. , Guldberg Robert E.
Published: January 2007

Porous scaffold biomaterials may offer a clinical alternative to bone grafts; however, scaffolds alone are typically insufficient to heal large bone defects. Numerous studies have demonstrated that osteoinductive growth factor or gene delivery significantly improves bone repair. However, given the important role of vascularization during bone regeneration, it may also be beneficial to incorporate factors that promote vascular ingrowth into constructs. In this study, a strategy combining structural polycaprolactone‐20% tricalcium phosphate (PCL‐TCP) composite scaffolds with platelet‐rich plasma (PRP) was tested. Following bilateral implantation of constructs into 8 mm rat nonunion femoral defects, 3D vascular and bone ingrowth were quantified at 3 and 12 weeks using contrast‐enhanced microcomputed tomography (micro‐CT) imaging. At week 3, PRP‐treated femurs displayed 70.3% higher vascular volume fraction than control femurs. Interestingly, bone volume fraction (BVF) was significantly higher for the empty scaffold group at the early time point. At 12 weeks, BVF measurements between the two groups were statiscally equivalent. However, a greater proportion of PRP‐treated femurs (83%) achieved bone union as compared to empty scaffold controls (33%). Consistent with this observation, biomechanical evaluation of functional integration also revealed a significantly higher torsional stiffness observed for PRP‐treated defects compared to empty scaffolds. Ultimate torque at failure was not improved, however, perhaps due to the slow resorption profile of the scaffold material. Histological evaluation illustrated infiltration of vascularized connective tissue and bone in both groups. Given that bone ingrowth into untreated defects in this model is minimal, PCL‐TCP scaffolds were clearly able to promote bone ingrowth but failed to consistently bridge the defect. The addition of PRP to PCL‐TCP scaffolds accelerated early vascular ingrowth and improved longer‐term functional integration. Taken together, the results of this study suggest that the use of PRP, alone or in combination with other bioactive components, may be an effective approach to augment the ability of porous biomaterial scaffolds to repair orthotopic defects. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2007
Multivariate and geometric morphometrics in the analysis of sexual dimorphism variation in Podarcis lizards
Authors: Kaliontzopoulou Antigoni , Carretero Miguel A. , Llorente Gustavo A.
Published: January 2007

Podarcis bocagei and P. carbonelli are two closely related lacertid species, very similar morphologically and ecologically. We investigated sexual dimorphism patterns presented by both species in allopatry and in sympatry. Sexual size and shape dimorphism patterns were analyzed using both multivariate and geometric morphometric techniques. Multivariate morphometrics revealed a marked sexual dimorphism in both species—males being larger with more robust habitus and females presenting a longer trunk. General patterns of sexual size dimorphism are not modified in sympatry, although there is evidence for some morphological change in male head size. The application of geometric morphometrics offered a more detailed image of head shape and revealed that males present a more developed tympanic area than do females, while females have a more rounded head. Differences in the degree of sexual shape dimorphism were detected in sympatry, but no consistent patterns were observed. From the results of the study, and based on previous knowledge on the populations studied, we conclude that the morphological differences observed are probably not caused by exploitative competition between the species, but rather appear attributable to the modification of the relative influence of sexual and natural selection on both sexes. J. Morphol., 2007. © 2007 Wiley‐Liss, Inc.