bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional Studies of Synthetic Gramicidin Hybrid Ion Channels in CHO Cells
Authors: Wesolowski Ryszard , Sommer Anna , Arndt Hans‐Dieter , Koert Ulrich , Reiß Philipp , Wimmers Sönke , Strauss Olaf
Published: February 2007

The function of a gramicidin hybrid ion channel in living Chinese hamster ovary (CHO) cells was investigated by the patch clamp method. The synthetic ion channel 1 consists of two cyclohexyl ether amino acids that link two minigramicidin strands. With 1 at a concentration of 1.0 μM, an increase in the whole‐cell membrane conductance was observed after 1.37 min. The conductance showed larger currents when Cs+ was used as charge carrier than when Na+ and K+ were used. In single‐channel recordings with Cs+ as charge carrier, the substance showed comparable single‐channel amplitudes in the membrane of living cells and artificial black lipid bilayers. In addition to functioning as a cation channel, compound 1 appeared to be a water channel. Exposure of the CHO cells to an extracellular hypoosmotic solution did not substantially change the cell volume. Extracellular hypoosmotic conditions in the presence of 1 increased the cell size to 146.5 % that of the control. Thus, the synthetic hybrid channel 1 can function as a cation channel with some Cs+ specificity, and as a water channel in CHO cells.
A Self‐Immolative Reporter For β‐Galactosidase Sensing
Authors: Ho Nan‐Hui , Weissleder Ralph , Tung Ching‐Hsuan
Published: February 2007

A dual fluorogenic and chromogenic probe, Gal–2SBPO, has been developed based on a synthesized water‐soluble dye, 9‐di‐3‐sulfonyl‐propylaminobenzo[a]phenoxazonium perchloride (2SPBO, λex/em=630/670 nm). β‐D‐Galactopyranoside, the substrate of β‐galactosidase, was conjugated to 2SBPO through a para‐substituted benzyloxycarbonyl group and a glycine residue, which serve as a self‐immolative spacer and as a molecular blocker to mask the optical signal of 2SBPO, respectively. Gal–2SBPO was soluble and stable under physiological conditions. Enzymatic cleavage of the β‐D‐galactopyranoside triggered a series of spontaneous reactions that resulted in a release of optically active 2SBPO. The β‐galactosidase activity was assayed by monitoring the absorbance at 630 nm and fluorescence at 670 nm.
Porous Iron Oxide Based Nanorods Developed as Delivery Nanocapsules
Authors: Wu Ping‐Ching , Wang Wen‐Shiuan , Huang Ying‐Ting , Sheu Hwo‐Shuenn , Lo Yi‐Wei , Tsai Tsung‐Lin , Shieh Dar‐Bin , Yeh Chen‐Sheng
Published: February 2007

A low‐temperature solution approach (90–95 °C) using FeCl3 and urea was carried out to synthesize β‐FeOOH nanorods in aqueous solution. The as‐synthesized β‐FeOOH nanorods were further calcined at 300 °C to form porous nanorods with compositions including both β‐FeOOH and α‐Fe2O3. The derived porous nanorods were engineered to assemble with four layers of polyelectrolytes (polyacrylic acid (PAA)/polyethylenimine(PEI)/PAA/PEI) on their surfaces as polyelectrolyte multilayer nanocapsules. Fluorescein isothiocyanate (FITC) molecules were loaded into the polyelectrolyte multilayer nanocapsules in order to investigate drug release and intracellular delivery in Hela cells. The as‐prepared nanocapsules showed ionic strength‐dependent control of the permeability of the polyelectrolyte shells. The release behavior of the entrapped FITC from the FITC‐loaded nanocapsules exhibited either controlled‐ or sustained‐release trends, depending on the compactness of the polyelectrolyte shells on the nanorod surfaces. Cytotoxicity measurements demonstrate that the native nanorods and the polymer‐coated nanorods have excellent biocompatibility in all dosages between 0.1 ng mL−1 and 100 μgm L−1. The time dependence of uptake of FITC‐loaded nanocapsules by Hela cancer cells observed by laser confocal microscopy indicates that the nanocapsules can readily be taken up by cancer cells in 15 min, a relatively short period of time, while the slow release of the FITC from the initial perimembrane space into the cytoplasm was followed by release into the nucleus after 24 h.
Efficient H/D Exchange Reactions of Alkyl‐Substituted Benzene Derivatives by Means of the Pd/C–H2–D2O System
Authors: Esaki Hiroyoshi , Aoki Fumiyo , Umemura Miho , Kato Masatsugu , Maegawa Tomohiro , Monguchi Yasunari , Sajiki Hironao
Published: February 2007

A method for efficient and extensive H/D exchange of substituted benzene derivatives which is catalyzed by heterogeneous Pd/C in D2O as a deuterium source under hydrogen atmosphere is described. Multideuterium incorporation into unactivated linear or branched alkyl chains that bear a carboxyl, hydroxyl, ether, ester, or amide moiety and are connected with a benzene ring was achieved by using the Pd/C–H2–D2O system. The present method does not require expensive deuterium gas or any special equipment.
Cardiac angiosarcoma: Report of a case diagnosed by echocardiographic‐guided fine‐needle aspiration
Authors: Bhalla Ritu , Nassar Aziza
Published: February 2007

The authors present a case of cardiac angiosarcoma diagnosed by fine‐needle aspiration (FNA) in a 33‐year‐old male. A percutaneous right atrial mass biopsy was performed via a right internal jugular venous approach and under echocardiographic guidance. FNA showed pleomorphic spindle‐shaped cells present singly and in small clusters in a background of hemorrhage. Occasional pseudo‐acini or microacinar structures were observed, that are lined with abnormal spindly to polygonal cells, indicative of vasoformative structures. Immunostain for CD31 was strongly positive. A diagnosis of cardiac angiosarcoma was made, following which, the patient underwent treatment with chemotherapy. Diagn. Cytopathol. 2007;35:164–166. © 2007 Wiley‐Liss, Inc.
Clear cell and eosinophilic oncocytomas of salivary gland: Cytological variants or parallels?
Authors: Saqi Anjali , Giorgadze Tamar A. , Eleazar Jennifer , Remotti Fabrizio , Vazquez Madeline F.
Published: February 2007

Oncocytomas are uncommon tumors of the salivary gland. They have an abundance of mitochondria, which is manifested as granular eosinophilic cytoplasm by light microscopy. On histological sections, presence of cytoplasmic glycogen and/or fixation artifact can impart cytoplasmic clearing, and oncocytomas with a predominance of clear cytoplasm are labeled clear cell oncocytomas. Two forms of oncocytoma, eosinophilic and clear cell, have been described in the surgical pathology literature. The purpose of this manuscript is to conduct a comparative cytological assessment to ascertain parallels and differences between the two variants. Diagn. Cytopathol. 2007;35:158–163. © 2007 Wiley‐Liss, Inc.
Immunocytochemical study of the expression of mesothelin in fine‐needle aspiration biopsy specimens of pancreatic adenocarcinoma
Authors: Baruch Amy C. , Wang Huamin , Staerkel Gregg A. , Evans Douglas B. , Hwang Rosa Frances , Krishnamurthy Savitri
Published: February 2007

Mesothelin is a potential marker of pancreatic adenocarcinoma that was recently identified by serial analysis of gene expression. We evaluated the sensitivity and specificity of mesothelin as a marker of pancreatic adenocarcinoma on destained Papanicolaou (Pap) smears and unstained cellblocks from 28 patients using a monoclonal antibody to mesothelin. Intensity and proportion of staining was semiquantitatively graded on a scale of 1–3, and as 0%, 1 to <10%, 10–50%, or >50%. Positive staining for mesothelin was seen in 64% of the direct smears and in 36% of cell block sections. Focal positivity for mesothelin was noted in benign pancreatic tissue in one of 10 cases. Staining was most often focal (<50% of cells) in both direct smears and cell block sections. The overall sensitivity and specificity of mesothelin as a marker for pancreatic adenocarcinoma were 68% and 90%, respectively. Sensitivity was higher in Pap smears than in cell block sections (64% versus 36%). The presence of occasional mesothelin expression in benign tissue, its very focal expression in malignant tissue may limit the utility of mesothelin as a marker of pancreatic adenocarcinomas in fine‐needle aspiration (FNA) specimens. Diagn. Cytopathol. 2007;35:143–147. © 2007 Wiley‐Liss, Inc.
Karyomegalic interstitial nephritis: A pitfall in urine cytology
Authors: Palmer David , Lallu Sharda , Matheson Philip , Bethwaite Peter , Tompson Keneth
Published: February 2007

A case of a 44‐yr‐old Maori female presenting with chronic renal failure due to karyomegalic interstitial nephritis is reported. To our knowledge, this is the first instance this disorder has been reported in a New Zealand Maori.

Karyomegalic interstitial nephritis is a rare cause of progressive renal failure, which may be familial, and is frequently associated with a history of recurrent respiratory infections.

The urine in this case contained large, pleomorphic cells, mimicking carcinoma. The case therefore illustrates a rare cause of chronic renal failure, and presents an important diagnostic pitfall in the practice of urine cytopathology. Diagn. Cytopathol. 2007;35:179–182. © 2007 Wiley‐Liss, Inc.
Fine‐needle aspiration of malignant mesothelioma with unusual morphologic features: A case report
Authors: Kapur Umesh , Wojcik Eva M.
Published: February 2007

Malignant mesothelioma is an aggressive neoplasm linked to asbestos exposure. Most mesothelioma patients present with pleural effusion and the fluid is typically sent for cytological examination. Therefore, cytopathologists are most familiar with features of mesothelioma in fluid preparations. We present here a case of malignant mesothelioma with unusual cytological features diagnosed on FNA. The diagnosis was confirmed by immunohistochemcal and electron microscopic studies. In addition, we compare the cytomorphological features observed in malignant effusion versus fine‐needle aspiration. Diagn. Cytopathol. 2007;35:174–178. © 2007 Wiley‐Liss, Inc.
Esophageal leiomyosarcoma diagnosed by endoscopic ultrasound‐guided fine‐needle aspiration
Authors: Stelow Edward B. , Jones David R. , Shami Vanessa M.
Published: February 2007

Endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) has proven itself to be a reliable method for the diagnosis of gastrointestinal stromal tumors and other gastrointestinal mesenchymal neoplasms. The diagnosis and distinction of these entities remain important, as these neoplasms have different prognoses and treatment options. We present a case of a 14.5‐cm esophageal mass in a 67‐yr‐old woman sampled by EUS‐FNA. Smears showed a cellular, spindle cell lesion with marked cytologic and nuclear pleomorphism. A cell block showed neoplastic cells reacting strongly with antibodies to smooth muscle antigens and not with antibodies to keratin, CD34 and CD117. Resection confirmed the diagnosis of esophageal leiomyosarcoma. To the best of our knowledge, this represents the first reported case of an esophageal leiomyosarcoma diagnosed by EUS‐FNA. Clinical, imaging, and cytologic features as well as differential diagnosis are discussed. Diagn. Cytopathol. 2007;35:167–170. © 2007 Wiley‐Liss, Inc.
Evolution of Pap testing at a community hospital—A ten year experience
Authors: Nance Keith V.
Published: February 2007

Over a 10‐year period the Pap program at our community hospital laboratory progressed from the use of 100% conventional smears to predominantly ThinPrep® (TP) and then to nearly 100% SurePath® (SP). During this period the annual Pap volume grew from less than 20,000 to nearly 50,000. This retrospective review focuses on improvements in high‐grade squamous intraepithelial lesion (HSIL) detection rates and specimen adequacy rates during the 10‐year period.

The laboratory database was used to identify 310,080 Pap test records between 1995 and 2004 inclusive. Pap type differences in HSIL detection rates and specimen adequacy rates were examined using the Cochran–Mantel–Haenszel test, with year as the stratification variable. The Breslow–Day test was used to evaluate the consistency of differences across the years. The overall results are summarized below in tabular format.

Results of Combined 10‐Year Data for Total Number of Cases, HSIL Rate, and Unsatisfactory Specimen Rate by Pap Method are given:

Pap Method
Total Paps
Total % HSIL
Total % Unsat

Conv Smear
128,630
0.28
0.30

ThinPrep®
88,575
0.38
0.64

SurePath®
92,875
0.50
0.17

HSIL detection rates were significantly higher for liquid‐based Pap tests compared with conventional smears (P < 0.0001). In addition, SP was associated with higher HSIL detection rates than TP with an estimated common odds ratio (OR) of 1.37 (95% confidence interval (CI), 1.10 − 1.71; P = 0.005), and higher specimen adequacy compared with TP or conventional Pap methods (P < 0.0001). Diagn. Cytopathol. 2007;35:148–153. © 2007 Wiley‐Liss, Inc.
Invasive ductal carcinoma of the breast with signet‐ring cell and mucinous carcinoma components: Diagnostic utility of immunocytochemistry of signet‐ring cells in aspiration cytology materials
Authors: Kuroda Naoto , Fujishima Nokiaki , Ohara Masahiko , Hirouchi Takashi , Mizuno Keiko , Lee Gang‐Hong
Published: February 2007

Breast cancer with signet‐ring cells is very rare. In this article, we present a case of invasive ductal carcinoma with signet‐ring cells and mucinous carcinoma components, which could be diagnosed as a primary cancer by immunocytochemical study of fine‐needle aspiration cytology material. A 73‐yr‐old Japanese woman noticed a palpable mass in the left breast. The aspiration cytology disclosed the monotonous proliferation of signet‐ring cell with cytological atypia. The immunocytochemical examination of neoplastic cells showed a positive reaction for estrogen receptor. The extensive examination of body before the operation did not disclose any tumors in other anatomic sites. The histological examination of surgically resected breast tumor showed invasive ductal carcinoma with foci of signet‐ring cell and mucinous carcinomas. Finally, our preliminary report suggests that immunocytochemical examination of aspiration cytology materials may provide useful information in searching the primary site of breast carcinoma with signet‐ring cells. Diagn. Cytopathol. 2007;35:171–173. © 2007 Wiley‐Liss, Inc.
HOXA13 directly regulates EphA6 and EphA7 expression in the genital tubercle vascular endothelia
Authors: Shaut Carley A. , Saneyoshi Chie , Morgan Emily A. , Knosp Wendy M. , Sexton Diane R. , Stadler H. Scott
Published: February 2007

Hypospadias, a common defect affecting the growth and closure of the external genitalia, is often accompanied by gross enlargements of the genital tubercle (GT) vasculature. Because Hoxa13 homozygous mutant mice also exhibit hypospadias and GT vessel expansion, we examined whether genes playing a role in angiogenesis exhibit reduced expression in the GT. From this analysis, reductions in EphA6 and EphA7 were detected. Characterization of EphA6 and EphA7 expression in the GT confirmed colocalization with HOXA13 in the GT vascular endothelia. Analysis of the EphA6 and EphA7 promoter regions revealed a series of highly conserved cis‐regulatory elements bound by HOXA13 with high affinity. GT chromatin immunoprecipitation confirmed that HOXA13 binds these gene‐regulatory elements in vivo. In vitro, HOXA13 activates gene expression through the EphA6 and EphA7 gene‐regulatory elements. Together these findings indicate that HOXA13 directly regulates EphA6 and EphA7 in the developing GT and identifies the GT vascular endothelia as a novel site for HOXA13‐dependent expression of EphA6 and EphA7. Developmental Dynamics 236:951–960, 2007. © 2007 Wiley‐Liss, Inc.
Tob genes in development and homeostasis
Authors: Jia Shunji , Meng Anming
Published: February 2007

Members of the Btg/Tob protein family share a conserved N‐terminal region that confers the activity to inhibit cell proliferation. Tob1 and Tob2 proteins, which constitute a Tob subfamily, have a longer C‐terminal region than BTG proteins. Apparently, genomes of invertebrates and teleost species contain only a single Tob locus, whereas genomes of mammalian, avian, and amphibian species contain two Tob loci (Tob1 and Tob2). Tob genes are expressed in oocytes, sperm, early embryos, and various adult tissues, depending on the species. Recent reports indicate that Tob proteins play important roles in spermatogenesis, embryonic dorsoventral patterning, osteogenesis, T‐cell activation, and learning and memory. Accumulating evidence supports the hypothesis that Tob proteins act primarily as transcriptional repressors in several signaling pathways. Developmental Dynamics 236:913–921, 2007. © 2007 Wiley‐Liss, Inc.
System for inducible expression of cre‐recombinase from the Foxa2 locus in endoderm, notochord, and floor plate
Authors: Frank Deborah U. , Elliott Sarah A. , Park Eon Joo , Hammond Jennetta , Saijoh Yukio , Moon Anne M.
Published: February 2007

We targeted the reverse tetracycline controlled transactivator (rtTA) to the Foxa2 locus (Foxa2ITA) to generate a system for regulating Cre‐recombinase activity within Foxa2 expression domains, including the endoderm, notochord, and floor plate of early mouse embryos. The use of an internal ribosomal entry site to obtain rtTA expression preserves Foxa2 function of the targeted allele. Cre activity with this system reflects the level of endogenous Foxa2 activity and is also tightly controlled by doxycycline. The location of Cre activity within the broader Foxa2 expression domain can be restricted by altering the timing of doxycycline administration. Isolated floor plate expression can be obtained in this manner. This system will provide a useful tool for manipulating gene expression in endoderm, notochord, and floor plate, all of which are tissues with important structural and patterning functions during embryogenesis. Developmental Dynamics 236:1085–1092, 2007. © 2007 Wiley‐Liss, Inc.
Epigenetics in development
Authors: Kiefer Julie C.
Published: February 2007

It has become increasingly evident in recent years that development is under epigenetic control. Epigenetics is the study of heritable changes in gene function that occur independently of alterations to primary DNA sequence. The best‐studied epigenetic modifications are DNA methylation, and changes in chromatin structure by histone modifications, and histone exchange. An exciting, new chapter in the field is the finding that long‐distance chromosomal interactions also modify gene expression. Epigenetic modifications are key regulators of important developmental events, including X‐inactivation, genomic imprinting, patterning byHoxgenes and neuronal development. This primer covers these aspects of epigenetics in brief, and features an interview with two epigenetic scientists. Developmental Dynamics 236:1144–1156, 2007. © 2007 Wiley‐Liss, Inc.
High‐resolution mapping of the Gli3 deletion in the mouse extra‐toesH mutant
Authors: Genestine Matthieu , Robert Benoît , Lallemand Yvan
Published: February 2007

Extra‐toes is a semidominant mutation that affects the Gli3 gene and provokes limb and brain abnormalities. Among the different alleles of this mutation, XtH is due to a deletion that has not yet been fully characterized. Using a PCR‐based strategy, we undertook a high‐resolution mapping of this deletion and confirmed that XtH is a null allele of Gli3. We further designed a PCR test to identify unequivocally heterozygous and homozygous embryos from their wild‐type littermates. Despite the length of the XtH deletion, available data on the mouse genome indicate that no genes other than Gli3 are deleted in XtH mutants. Thus, the XtH mutation can be used as a model for studying the effects that absence of Gli3 function has during development. genesis 45:107–112, 2007. © 2007 Wiley‐Liss, Inc.
A Basic Ionic Liquid as Catalyst and Reaction Medium: A Rapid and Simple Procedure for Aza‐Michael Addition Reactions
Authors: Xu Jian‐Ming , Wu Qi , Zhang Qing‐Yi , Zhang Fu , Lin Xian‐Fu
Published: February 2007

A fast, mild, and quantitative procedure for Michael addition reactions between various amines and α,β‐unsaturated carbonyl compounds and nitriles in the presence of an easily accessible basic ionic liquid – 3‐butyl‐1‐methylimidazolium hydroxide, [bmIm]OH – as both catalyst and reaction medium has been developed. For large‐scale reactions the products could be directly distilled from the ionic liquid, allowing the use of organic solvents to be avoided totally. The ionic liquid could be reused at least eight times with consistent activity and was stable during the reaction process. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Application of pressure cycling technology to tissue sample preparation for 2‐DE
Authors: Ringham Heather , Bell Richard L. , Smejkal Gary B. , Behnke James , Witzmann Frank A.
Published: February 2007

2‐DE is a powerful protein analytical tool whose major strengths include semiglobal quantitation and charge separation of complex protein mixtures, enabling the analysis of differential protein expression, and variable post‐translational modification. One of 2‐DE's limitations relates to its limited dynamic range and consequently the number of proteins expressed that can be analyzed on a single gel. In an attempt to improve the yield of detectable proteins during sample preparation, we applied a novel extraction technique called pressure cycling technology.
Solute separation in nanofluidic channels: Pressure‐driven or electric field‐driven?
Authors: Xuan Xiangchun , Li Dongqing
Published: February 2007

We demonstrate theoretically that solute separation can be accomplished in pressure‐driven flow through nanochannels due to solute–wall interactions. Such pressure‐driven separation is efficient in identifying solutes with variable valences. This function complements exactly the electric field‐driven separation (i.e., electrophoretic separation) in nanofluidic channels that works well for solutes differing in diffusivity. We also demonstrate the enhanced separation of solutes of either different valence or different diffusivity through the combination of a pressure‐driven flow and an electric field‐driven backflow in nanofluidic channels. This combined flow, however, has to be used with caution for solutes varying in both valence and diffusivity.
Electroosmotic flow mixing in zigzag microchannels
Authors: Chen Jia‐Kun , Yang Ruey‐Jen
Published: February 2007

In this study we performed numerical and experimental investigations into the mixing of EOFs in zigzag microchannels with two different corner geometries, namely sharp corners and flat corners. In the zigzag microchannel with sharp corners, the flow travels more rapidly near the inner wall of the corner than near the outer wall as a result of the higher electric potential drop. The resulting velocity gradient induces a racetrack effect, which enhances diffusion within the fluid and hence improves the mixing performance. The simulation results reveal that the mixing index is approximately 88.83%. However, the sharp‐corner geometry causes residual liquid or bubbles to become trapped in the channel at the point where the flow is almost stationary, when the channel is in the process of cleaning. Accordingly, a zigzag microchannel with flat‐corner geometry is developed. The flat‐corner geometry forms a convergent–divergent type nozzle which not only enhances the mixing performance in the channel, but also prevents the accumulation of residual liquid or bubbles. Scaling analysis reveals that this corner geometry leads to an effective increase in the mixing length. The experimental results reveal that the mixing index is increased to 94.30% in the flat‐corner zigzag channel. Hence, the results demonstrate that the mixing index of the flat‐corner zigzag channel is better than that of the conventional sharp‐corner microchannel. Finally, the results of Taguchi analysis indicate that the attainable mixing index is determined primarily by the number of corners in the microchannel and by the flow passing height at each corner.
Computer‐assisted 2‐D agarose electrophoresis of Haemophilus influenzae type B meningitis vaccines and analysis of polydisperse particle populations in the size range of viruses: A review
Authors: Tietz Dietmar
Published: February 2007

When protein–polysaccharide conjugated vaccines were first developed for the immunization of small children against meningitis caused by infection with Haemophilus influenzae type b (Hib), the vaccine preparations varied in immunogenicity. Testing for immunogenicity was time‐consuming and alternative analytical procedures for determining vaccine quality were unsatisfactory. For example, due to the very high molecular weight of the vaccine particles, immunogens could only be physically characterized as a fraction in the void volume of Sepharose gel filtration. In search of better analytical methods, a computer‐assisted electrophoretic technique for analyzing such vaccines was developed in the period from 1983 to 1995. This new approach made it possible to analyze highly negatively charged particles as large as or larger than intact viruses. 2‐D gel patterns were generated that varied depending on the conditions of the particular vaccine preparation and were therefore characteristic of each vaccine sample. Thus, vaccine particle populations with a continuous size variation over a wide range (polydisperse) could be characterized according to size and free mobility (related to particle surface net charge density). These advances are reviewed in this article, since the developed methods are still a promising tool for vaccine quality control and for predicting immunogen effectiveness in the production of vaccines. The technique is potentially beneficial for Hib immunogens and other high‐molecular‐mass vaccines. Additional biomedical applications for this nondenaturing electrophoretic technique are briefly discussed and detailed information about computational and mathematical procedures and theoretical aspects is provided in the Appendices.
Transport and deformation of droplets in a microdevice using dielectrophoresis
Authors: Singh Pushpendra , Aubry Nadine
Published: February 2007

In microfluidic devices the fluid can be manipulated either as continuous streams or droplets. The latter is particularly attractive as individual droplets can not only move but also split and fuse, thus offering great flexibility for applications such as laboratory‐on‐a‐chip. We consider the transport of liquid drops immersed in a surrounding liquid by means of the dielectrophoretic force generated by electrodes mounted at the bottom of a microdevice. The direct numerical simulation (DNS) approach is used to study the motion of droplets subjected to both hydrodynamic and electrostatic forces. Our technique is based on a finite element scheme using the fundamental equations of motion for both the droplets and surrounding fluid. The interface is tracked by the level set method and the electrostatic forces are computed using the Maxwell stress tensor. The DNS results show that the droplets move, and deform, under the action of nonuniform electric stresses on their surfaces. The deformation increases as the drop moves closer to the electrodes. The extent to which the isolated drops deform depends on the electric Weber number. When the electric Weber number is small, the drops remain spherical; otherwise, the drops stretch. Two droplets, however, that are sufficiently close to each other, can deform and coalesce, even if the electric Weber number is small. This phenomenon does not rely on the magnitude of the electric stresses generated by the bulk electric field, but instead is due to the attractive electrostatic drop–drop interaction overcoming the surface tension force. Experimental results are also presented and found to be in agreement with the DNS results.
Counter‐flow gradient electrofocusing
Authors: Shackman Jonathan G. , Ross David
Published: February 2007

Counter‐flow gradient electrofocusing techniques are methods whereby a combination of electrophoresis and a bulk solution counter‐flow is used to accumulate or focus analytes at stationary points along a separation column. This review first describes the various forms of counter‐flow gradient electrofocusing that have been demonstrated in the literature and then compares figures of merit for counter‐flow focusing methods and conventional CE methods. In an effort to compare the concentration enhancement of the various focusing techniques against each other, as well as of stacking methods, the parameter of analyte‐accumulation velocity is introduced and employed to normalize the efficacy of the techniques.
Comparison between objective and subjective measurements of quality of service over an Optical Wide Area network
Authors: Matera Francesco , Matteotti Francesca , Pasquali Paolo , Rea Luca , Tarantino Alessandro , Baroncini Vittorio , Del Prete Giuseppe , Gaudino Giancarlo
Published: February 2007

The introduction of intelligence for management and control of the quality of service (QoS) are key issues for the evolution of the next generation IP optical network based on Ethernet technology. A test bed of a core‐access network was implemented to investigate such issues and in this paper, the authors report measurements concerning the QoS of multimedia services for different traffic conditions. The network was implemented with a differentiated service over Multi‐Protocol Label Switch (MPLS) architecture; it consists of a real optical network based on core routers with optical Gigabit Ethernet (GBE) interfaces connected by means of long single mode fibres (about 50\,km), contained in an installed cable between Rome and Pomezia. The network is based on different access devices, but in this paper we only refer to an access based on Fibre To The building (FTTB) architecture. The QoS was investigated both in terms of network (or objective) tests that include packet loss, jitter, one way delay and throughput measurements and perceptive (or subjective) tests that conversely are based on the evaluation of user perception. The services under test mainly consisted of video streams that circulated in the network according to the switching operations based in the IP differentiated service over MPLS technique that allowed us to guarantee the QoS for some class of service, also in the presence of network overload. Particular attention was given to the correlation between objective and subjective measurements. Furthermore, in order to have a complete analysis about QoS of real networks, measurements were performed also in the presence of restoration operations for link failures; in particular we compare the results in the case of conventional IP network restoration with a procedure proposed by us and based on a link switching activated by the loss of signal command coming from the routers. Copyright © 2007 John Wiley & Sons, Ltd.
Stable carbon isotope signature of ancient maize agriculture in the soils of Motul de San José, Guatemala
Authors: Webb Elizabeth A. , Schwarcz Henry P. , Jensen Christopher T. , Terry Richard E. , Moriarty Matthew D. , Emery Kitty F.
Published: February 2007

Soil profiles collected from a 2.5‐km transect radiating from the Maya center of Motul de San José were analyzed for the stable carbon‐isotope composition of their soil organic matter. The residues of maize (Zea mays), the only C4plant known to have been cultivated in this area by the ancient Maya, impart a carbon‐isotope signature to the underlying soil organic matter reservoir that is distinct from that produced by the native C3forest vegetation. The varying turnover rates of the humic acid and humin fractions of the soil organic matter allowed us to distinguish between the presence of modern and ancient maize residues in these soils, and to delineate the lateral extent of maize cultivation at this ancient Maya site. The strongest isotopic evidence of maize residues is preserved in the soils surrounding the peripheral settlement of Chäkokot and at one locality within the urban center of Motul de San José. © 2007 Wiley Periodicals, Inc.
Application of carbon isotope analysis to ancient maize agriculture in the Petexbatún region of Guatemala
Authors: Johnson Kristofer D. , Wright David R. , Terry Richard E.
Published: February 2007

The ancient Maya subsisted in an environment limited by shallow soils and unpredictable weather patterns until their collapse ∼A.D. 800–900. Ancient subsistence can be a difficult subject, with little physical evidence of agricultural artifacts and structures. This study characterized soil profiles and utilized changes in stable carbon isotope ratios of soil organic matter (SOM) to locate and interpret areas of ancient C4plant growth and maize (Zea mays) cultivation among the Maya. The investigation indicated some of the challenges the Maya faced, including shallow and sloped soils in some areas. The C4plant signature was found in seasonal wetland soils on the opposite side of the Laguneta Aguateca from the ruins of Aguateca, but not in the perennial wetlands on the immediate side. No C4plant signature was detected in the shoulder and backslope soils. Based on these findings, the ancient Maya of Aguateca probably adapted to their environment by farming rich toeslope soils. It is possible that maize was also grown in the seasonal wetlands adjacent to the site. If the steep backslope soils around Aguateca were used in ancient agriculture, the evidence has probably eroded away. © 2007 Wiley Periodicals, Inc.
Biogeochemical studies of a Native American runoff agroecosystem
Authors: Sandor Jonathan A. , Norton Jay B. , Homburg Jeffrey A. , Muenchrath Deborah A. , White Carleton S. , Williams Stephen E. , Havener Celeste I. , Stahl Peter D.
Published: February 2007

Research on soil fertility is presented in the context of runoff agriculture, a venerable farming system that has been used for millennia in arid to semiarid regions, where water is a major limiting resource for crop production. The agroecology of runoff farming was studied with the Zuni to evaluate nutrient and hydrologic processes, management, maize productivity, and soil quality in some of the oldest recognized fields in the United States. This ancient Southwest agriculture has functioned without conventional irrigation or fertilization by tapping into biogeochemical processes in natural watersheds connected to fields. Carefully placed fields are managed on alluvial fans and other valley margin landforms to intercept runoff and associated sediment and organic debris transported from adjoining forested uplands. We report on research to evaluate and link nitrogen and phosphorus, two key nutrients for crop production, in watershed, soil, and crop components of this agroecosystem. Nutrient data have been collected by observational and experimental methods for each component and the transport of nutrients from watershed to field to maize. The condition of Zuni agricultural soils suggests that their knowledge and management of soils contributed to effective conservation. This study and others indicate the need for further long‐term monitoring and experimental research on watersheds, runoff processes, field soils, and crops across a range of arid to semiarid ecosystems. © 2007 Wiley Periodicals, Inc.
Galectin‐1 expression in cancer‐associated stromal cells correlates tumor invasiveness and tumor progression in breast cancer
Authors: Jung Eun‐Jung , Moon Hyeong‐Gon , Cho Bok Im , Jeong Chi‐Young , Joo Young‐Tae , Lee Young‐Joon , Hong Soon‐Chan , Choi Sang‐Kyung , Ha Woo‐Song , Kim Jae Won , Lee Chang‐Won , Lee Jong Sil , Park Soon‐Tae
Published: February 2007

Understanding the molecular background of breast cancer biology is critical in developing new biomarkers for earlier diagnosis and more optimized treatment. We performed a proteomic analysis of human breast carcinoma tissues to investigate the tumor‐specific protein expression in breast carcinoma. Using 2‐dimensional electorphoresis (2‐DE) and matrix‐assisted laser desorption/ionization‐time of flight‐mass spectrometry (MALDI‐TOF‐MS), we were able to identify a list of proteins which are upregulated in cancerous tissue. There was significant increase of galectin‐1 expression in all cancerous tissues compared to noncancerous tissues, and its increased expression was further confirmed by western blot immunostaining. Subsequent immunohistochemical staining against galectin‐1 in 105 breast cancer specimens showed significant correlation between galectin‐1 expression in cancer‐associated stromal cells and tumor invasiveness, T stage, TNM stage, and axillary lymph node metastasis. Galectin‐1 expressionin cancer cells showed no correlation to above‐mentioned pathologic variables. Hormonal receptor status and galectin‐1 expression showed no correlation. This study demonstrates the upregulation of galectin‐1 in breast carcinoma tissues and the clinical significance of galectin‐1 in breast cancer patients. Our data supports the recently highlighted roles of galectin‐1 in cancer‐associated stroma and in tumor immune privilege. © 2006 Wiley‐Liss, Inc.
Apoptotic effect of 3,4‐dihydroxybenzoic acid on human gastric carcinoma cells involving JNK/p38 MAPK signaling activation
Authors: Lin Hui‐Hsuan , Chen Jing‐Hsien , Huang Chi‐Chou , Wang Chau‐Jong
Published: February 2007

3,4‐Dihydroxybenzoic acid (protocatechuic acid, PCA) is discussed to represent antioxidative food components in a human diet rich in fruits and vegetables, and has been shown to prevent carcinogenesis or antitumor growth in vivo. However, the molecular mechanisms involved in chemopreventive activity of PCA are poorly understood. In this study, investigations were conducted to examine the detailed signaling pathway involved in PCA‐induced apoptosis in human gastric adenocarcinoma (AGS) cells. The data from cell viability assay showed that PCA exhibited the antiproliferation effect on AGS cells in a time‐ and dose‐dependent manner. The occurrence of apoptosis induced by PCA was confirmed by morphological and biochemical features, including apoptotic bodies formation and an increase in the distribution of hypodiploid phase. Molecular data showed the effect of PCA in AGS cells might be mediated via sustained phosphorylation and activation of JNK and p38 mitogen‐activating protein kinases (MAPK), but not ERK. Treatment with pharmacological inhibitors or transfection with the mutant p38 or/and JNK expression vector reduced PCA‐mediated apoptosis and the JNK/p38 MAPK‐related proteins phosphorylation and expression, including ATF‐2, c‐Jun, FasL, Fas, p53 and Bax. Preincubation with Nok‐1 monoclonal antibody, which is inhibitory to Fas signaling, interfered with PCA‐induced cleavage of procaspase and sensitization to anti‐APO‐induced apoptosis. These results suggest the possible involvement of multiple signaling pathways from the MAPK to the subsequent mitochondria‐ and/or Fas‐mediated caspase activation are potential requirements for PCA‐induced AGS apoptosis. Further, PCA effectively induced JNK/p38 activation in PCA‐response cell lines. Taken together, our data present the first evidence of PCA as an apoptosis inducer in AGS cells, even in tumor cells of digestive organs, and provide a new mechanism for its anticancer activity. © 2007 Wiley‐Liss, Inc.
Rapamycin together with herceptin significantly increased anti‐tumor efficacy compared to either alone in ErbB2 over expressing breast cancer cells
Authors: Wang Lu‐Hai , Chan Joseph L.‐K. , Li Wei
Published: February 2007

The objective of this study was to assess the anti‐tumor efficacy of rapamycin alone or in combination with herceptin in breast cancer. A total of 20 human breast cancer lines were examined for expression of various receptor tyrosine kinases and activation of their down stream signaling molecules, as well as for their invasion and colony forming ability. The ErbB2 and PI3 kinase pathway inhibitors were tested for the inhibition on breast cancer cell growth and tumor development. Seven of the 20 lines displayed an elevated level of ErbB2, others had varying level of EGF, IGF‐1 or insulin receptor. Over 30% of the lines also had constitutive activation of Akt and MAP kinase. The lines displayed a wide range of colony forming and invasion ability. The PI3 kinase pathway inhibitors LY294002 and rapamycin inhibited the colony forming ability of all of the lines with the ErbB2 overexpressing lines having a higher sensitivity. A similar trend was observed for inhibition of invasion by LY294002. Rapamycin alone and additively together with herceptin inhibited the breast cancer cell growth especially in ErbB2 overexpressing cells. Rapamycin and herceptin synergistically inhibited tumor growth and endpoint tumor load in a xenograft model using a MCF‐7 subline and in a MMTV‐ErbB2 transgenic model. Rapamycin and herceptin significantly reduced the level of cyclin D1 and D3 and increased the cleavage of caspase 3 suggesting an increased apoptosis. Our results suggest that rapamycin together with herceptin has an enhanced anti‐cancer effect and could be developed as an improved therapeutic regimen for breast cancer. © 2007 Wiley‐Liss, Inc.
Obesity, physical activity and the risk of pancreatic cancer in a large Japanese cohort
Authors: Lin Yingsong , Kikuchi Shogo , Tamakoshi Akiko , Yagyu Kiyoko , Obata Yuki , Inaba Yutaka , Kurosawa Michiko , Kawamura Takakshi , Motohashi Yutaka , Ishibashi Teruo ,   for the JACC Study Group
Published: February 2007

It is unclear whether body mass index (BMI) and physical activity are associated with the risk of pancreatic cancer in Asian populations. We examined these associations in the Japanese Collaborative Cohort Study for Evaluation of Cancer Risk. Our cohort study included 110,792 Japanese men and women at enrollment (1988–1990). Data on height, body weight (at baseline and at age 20 years) and physical activity were obtained from a questionnaire. Cox proportional hazards models were used to estimate the relative risks of pancreatic cancer mortality. We observed a total of 402 pancreatic cancer deaths during the follow‐up period. Men with a BMI of 30 or more at age 20 years had a 3.5‐fold greater risk compared with men with a normal BMI. Women with a BMI of 27.5–29.9 at baseline had ∼60% increased risk compared with women with a BMI of 20.0–22.4. In men, weight loss of 5 kg or more between 20 years of age and baseline age was associated with an increased risk of pancreatic cancer death. In contrast, women with weight loss of 5 kg or more over the same period had a decreased risk. Physical activity was not associated with pancreatic cancer risk in either men or women. Obesity in young adulthood may be associated with an increased risk of death from pancreatic cancer in Japanese men. The risk of pancreatic cancer in relation to BMI seems to differ according to sex and the period over which BMI was measured. © 2007 Wiley‐Liss, Inc.
Aggregation of cancer among relatives of never‐smoking lung cancer patients
Authors: Gorlova Olga Y. , Weng Shih‐Feng , Zhang Yiqun , Amos Christopher I. , Spitz Margaret R.
Published: February 2007

The authors evaluated the familial aggregation of lung and other cancers in first‐degree relatives of lung cancer patients self‐reported to be lifetime never smokers. The data, derived from a large lung cancer case–control study, included 2,465 first‐degree relatives of 316 never smoker lung cancer cases and 2,441 first‐degree relatives of 318 never smoker controls, frequency matched to the cases on age, gender and ethnicity. The median age of the cases and the controls was 61 years, about 2/3 were women, and about 80% were Caucasian. Overall, there was a 25% excess risk [95% CI (1.05–1.50)] of any type of cancer among the first‐degree relatives of cases, and case offspring exhibited a 2‐fold excess cancer risk (1.03–4.10) compared with control offspring. There was also a 44% excess risk (1.05–1.97) of young onset cancers (before age 50) among relatives of cases. Smoking case relatives had an increased risk of any cancer [odds ratio (OR) = 1.36 (1.03–1.81)] and a 5.52‐fold risk (1.19–25.51) of young onset lung cancer compared with smoking control relatives. Female case relatives had a 58% excess breast cancer risk (1.04–2.43), and case mothers a 2.57‐fold breast cancer risk (1.16–4.24). A significant excess of testicular cancer was observed among case male relatives [OR = 12.32 (1.71–88.90)], although based on only 9 cases. The age at lung cancer diagnosis tended to be earlier in case relatives (61.4, SD = 12.9) compared with control relatives (66.2, SD = 11.4; p = 0.07). Our analysis provides further evidence for the importance of genetic factors for lung cancer in never smokers. © 2007 Wiley‐Liss, Inc.
Inhibition of CDK4 impairs proliferation of pancreatic cancer cells and sensitizes towards TRAIL‐induced apoptosis via downregulation of survivin
Authors: Retzer‐Lidl Michaela , Schmid Roland M. , Schneider Günter
Published: February 2007

Pancreatic ductal adenocarcinoma is one of the most common causes of cancer death in Western countries with an average survival after diagnosis of 3–6 months and a five‐year survival rate under 5%. Because of the lack of effective therapies, there is the need to characterize new molecular treatment strategies. Abnormal regulation of the cell cycle is a hallmark of neoplasia. Cyclin‐dependent kinase 4 (CDK4), a key regulator of G1‐phase of the cell cycle, has been shown to be overexpressed in pancreatic cancer. Until now, the contribution of CDK4 to tumor maintenance of pancreatic cancer has not been investigated. In this study, we used the chemical CDK4 inhibitor 2‐bromo‐12,13‐dihydro‐5H‐indolo[2,3‐a]pyrrolo[3,4‐c]carbazole‐5,7(6H)‐dione, as well as RNA interference, to investigate the function of CDK4 in pancreatic cancer cells. Both approaches led to a reduction of pancreatic cancer cell proliferation due to G1‐phase cell cycle arrest and Rb activation. Furthermore, we observed increased sensitivity of G1‐arrested pancreatic cancer cells towards TRAIL‐induced apoptosis. Sensitization towards TRAIL was due to the transcriptional downregulation of survivin. These findings show that a combined sensitizer/inducer strategy may be a potential therapeutic strategy for pancreatic ductal adenocarcinoma. © 2007 Wiley‐Liss, Inc.
Concordance of Species Composition Patterns among Microcrustaceans, Rotifers and Testate Amoebae in a Shallow Pond
Authors: Bini Luis Mauricio , Galli Vieira Ludgero Cardoso , Machado Juliana , Machado Velho Luiz Felipe
Published: February 2007

In this study, spatial concordance among microcrustaceans, rotifers and testate amoebae was examined in a small pond in Central Brazil. The main goal was to test how consistently different taxonomic groups ordinate 9 sites distributed along the pond's main axis. Microcrustaceans were more abundant during the dry season, characterized by waters with high transparency and dissolved oxygen concentration. An increase in species richness and densities of rotifers and testate amoebae was detected during rainy season, with low values of Secchi disk and concentrations of dissolved oxygen. However, the ordination patterns generated by these groups were different. Concordant patterns across sites were found only between cladocerans and copepods. These results suggest that great care should be taken when ordination patterns based on some taxonomic groups are extrapolated to other groups for detecting environmental changes. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)