bluuebunny/crossref_metadata_2025 huggingface dataset:
Hippocampal spreading depression bilaterally activates the caudal trigeminal nucleus in rodents
Authors: Kunkler Phillip E. , Kraig Richard P.
Published: October 2003

Spreading depression (SD) and migraine aura involve transiently altered (i.e., increased followed by decreased) electrophysiological activity that propagates at the distinctive rate of millimeters per minute (mm/min), leading to the suggestion that they (and perhaps pain from migraine) are causally related via changes in the same brain structure. Neocortex is considered the anatomical zone associated with migraine aura and is the sole area known to induce caudal trigeminal nucleus (TNC) activation from SD in rodents. However, classical evidence of SD in human neocortex is reported only with severe brain disease, while migraine is a common and comparatively benign disorder. Because SD occurs in human hippocampus, and memory dysfunction referable to hippocampus is seen in migraineurs, we determined whether recurrent SD confined to hippocampus in rat could induce TNC activation. Our work shows that recurrent hippocampal SD evoked a significant (P < 0.05–0.001) increase in bilateral c‐fos immunostaining within TNC superficial laminae compared with sham controls. Furthermore, hippocampal SD occurred with a correlated and transient change in spontaneous activity and blood flow in the ipsilateral neocortex without spread of SD to that area. Thus, hippocampal SD may be a previously unrecognized, potential trigger for nociceptive activation of TNC perhaps associated with migraine. © 2003 Wiley‐Liss, Inc.
Orthotopic treatment model of prostate cancer and metastasis in the immunocompetent mouse: Efficacy of flt3 ligand immunotherapy
Authors: Somers Kenneth D. , Brown Roy R. , Holterman Daniel A. , Yousefieh Nazita , Glass William F. , Wright George L. , Schellhammer Paul F. , Qian Jesse , Ciavarra Richard P.
Published: October 2003

We established an orthotopic treatment model of prostate cancer to generate reproducible primary and metastatic carcinoma in immunocompetent C57BL/6 mice. Using an in vivo selection scheme of intraprostatic implantation of TRAMP‐C1 cells, primary prostate tumors were cultured and recycled three times by intraprostatic injection resulting in the selection and establishment of the recycled cell line TRAMP‐C1P3. Prostate tumors were detected ∼30 days post‐implantation with periaortic lymph node metastasis in 19/20 (95%) of mice. Tissue culture amplification, DNA ploidy and PCR amplification of the SV40 transgene were used to detect metastatic TRAMP‐C1P3 in lymph node specimens. Tissue culture amplification and DNA ploidy were as sensitive as SV40 transgene amplification by PCR in detection of early metastatic disease in draining lymph nodes. To establish the use of the orthotopic model of prostate cancer for immunotherapy, mice were injected orthotopically with TRAMP‐C1P3 cells and 7 days post‐implantation treated daily for 28 days with either flt3L or carrier control. Carrier‐treated mice had clinically detectable prostate tumors, lymph node metastasis and were moribund at 29–35 days, whereas flt3L therapy markedly suppressed primary TRAMP‐C1P3 growth and lymph node metastasis, and prolonged survival. In summary, we have established a reproducible and clinically relevant orthotopic treatment model of prostate cancer in immunocompetent mice with application to a variety of therapeutic strategies. We demonstrate that flt3L treatment suppressed orthotopic prostate tumor growth and lymph node metastasis reinforcing a role for flt3L as an immunotherapeutic strategy for prostate cancer. © 2003 Wiley‐Liss, Inc.
Reporter gene assay demonstrates functional differences in estrogen receptor activity in purified breast cancer cells: A pilot study
Authors: Singh Anjana , Ali Simak , Kothari Manish S. , De Bella Manuela Tamburo , Smith Clive , Timms Emma , Slade Martin J. , Foxwell Brian M. , Coombes R. Charles
Published: October 2003

Tamoxifen has contributed to a dramatic reduction in breast cancer mortality and recent results indicate that aromatase inhibitors may further improve survival in some patients. Nevertheless, a substantial proportion of patients become resistant to treatment. To date, with the exception of estrogen receptor (ER) determination by ligand binding or immunohistochemical techniques, there has been no way of predicting which of several therapies is indicated in particular patients. We describe a novel assay using the adenoviral gene delivery system to assess ER function in breast cancer cells derived directly from patients. The purification and short‐term culture of these cells has been recently described by our laboratory. Adenovirus containing an estrogen‐regulated β‐galactosidase reporter gene (ERE‐lacZ) was constructed and used to test ER activity in breast cancer cells derived from 18 patients with primary and 16 patients with metastatic cancer, under varying treatment schedules. The adenoviral assay enabled ER activity to be readily determined in purified cells from primary breast cancers and secondary sites. Breast cancers cells could be categorized on the basis of ER activity in the absence of ligand, the presence of estrogen or anti‐estrogens. In primary breast cancers, our results correlated with ER determination by immunohistochemistry in 78% of cases. In patients who had become resistant to tamoxifen, however, we found some in whom reporter activity was stimulated by tamoxifen and others whose tumors were either still estrogen responsive or completely unresponsive, irrespective of the original ER content. Our findings indicate that this reporter assay could be useful in decisions regarding use of adjuvant endocrine therapies in breast cancer. © 2003 Wiley‐Liss, Inc.
Condom use promotes regression of human papillomavirus–associated penile lesions in male sexual partners of women with cervical intraepithelial neoplasia
Authors: Bleeker Maaike C.G. , Hogewoning Cornelis J.A. , Voorhorst Feja J. , van den Brule Adriaan J.C. , Snijders Peter J.F. , Starink Theo M. , Berkhof Johannes , Meijer Chris J.L.M.
Published: October 2003

Penile HPV‐associated lesions are frequently seen in male sexual partners of women with CIN. The natural course and clinical significance of these lesions are unclear. Women with CIN and their male sexual partners were randomized for condom use (condom group n = 68, noncondom group n = 68). Males were screened for the presence of penile lesions, i.e., flat lesions, papular lesions and condylomata acuminata, and of HPV in their penile swabs by PCR testing. Median follow‐up time was 13.1 months (range 2.9–57.4). The outcome of our study was clinical regression of penile lesions defined as disappearance of lesions at penoscopy. Potentially prognostic factors, i.e., HPV status, lesion type and age, were studied as well. Outcomes were assessed in 57 men of the condom group and in 43 men of the noncondom group. Condom use shortened the median time to regression of flat penile lesions (7.4 months condom group vs. 13.9 months noncondom group; HR = 2.1, 95% CI 1.2–3.7). This effect was not found for papular lesions (HR = 0.5, 95% CI 0.1–2.8). HPV‐negative men showed a significantly shorter median time to regression of flat lesions (3.8 months) compared to men with either HPV‐positive status (8.5 months; HR = 0.4, 95% CI 0.2–0.9) or inconsistent HPV status (13.1 months; HR = 0.2, 95% CI 0.1–0.6). Regression of flat penile lesions is HPV‐dependent and accelerated by condom use. This effect is probably the result of blocking viral transmission between sexual partners. © 2003 Wiley‐Liss, Inc.
Hyaluronan synthase‐3 is upregulated in metastatic colon carcinoma cells and manipulation of expression alters matrix retention and cellular growth
Authors: Bullard Kelli M. , Kim Hyeong‐Rok , Wheeler Marie A. , Wilson Christopher M. , Neudauer Cheryl L. , Simpson Melanie A. , McCarthy James B.
Published: October 2003

HA is a glycosaminoglycan that is synthesized on the inner surface of the plasma membrane and secreted into the pericellular matrix. HA and its biosynthetic enzymes (HAS1, HAS2 and HAS3) are thought to participate in tumor growth and cancer progression. In our study, colon carcinoma cells isolated from a lymph node metastasis (SW620) produced more pericellular HA and expressed higher levels of HAS3 mRNA compared to cells isolated from a primary colon carcinoma (SW480). To assess functionality, HAS3 expression in SW620 cells was inhibited by transfection with an asHAS3 construct. Decreased HA secretion and cell‐surface retention by asHAS3 transfectants were confirmed using competitive binding and particle exclusion assays. Anchorage‐independent growth, a correlate of tumor growth in vivo, was assessed by colony formation in soft agar. SW620 cells stably transfected with asHAS3 demonstrated significant growth inhibition, as evidenced by fewer colonies and smaller colony area than either SW620 cells or cells transfected with vector alone. Addition of exogenous HA restored growth in asHAS3 transfectants. Thus, we demonstrate that pericellular HA secretion and retention and HAS3 expression are increased in metastatic colon carcinoma cells relative to cells derived from a primary tumor. Inhibition of HAS3 expression in these cells decreased the pericellular HA matrix and inhibited anchorage‐independent growth. These data suggest that HA and HAS3 function in the growth and progression of colon carcinoma. © 2003 Wiley‐Liss, Inc.
Single amino acid substitutions in the transmembrane domains of breast cancer resistance protein (BCRP) alter cross resistance patterns in transfectants
Authors: Miwa Miyu , Tsukahara Satomi , Ishikawa Etsuko , Asada Sakiyo , Imai Yasuo , Sugimoto Yoshikazu
Published: October 2003

Breast cancer resistance protein (BCRP) is a member of ATP‐binding cassette transporters that has an N‐terminal ATP binding domain and a C‐terminal transmembrane domain (TM). Expression of wild‐type BCRP confers resistance to multiple chemotherapeutic agents such as mitoxantrone, SN‐38 and topotecan, but not to doxorubicin. We made 32 BCRP mutants with an amino acid substitution in the TMs (7 E446‐mutants in TM2, 15 R482‐mutants in TM3, 4 N557‐mutants in TM5 and 6 H630‐mutants in TM6) and examined the effect of the substitutions on cellular drug resistance. PA317 cells transfected with any one of the 7 E446‐mutant BCRP cDNAs did not show drug resistance. Cells transfected with any one of the 13 R482X2‐BCRP cDNAs (X2 = N, C, M, S, T, V, A, G, E, W, D, Q and H, but not Y and K) showed higher resistance to mitoxantrone and doxorubicin than the wild‐type BCRP‐transfected cells. Cells transfected with N557D‐BCRP cDNA showed similar resistance to mitoxantrone but lower resistance to SN‐38 than the wild‐type BCRP‐transfected cells. Cells transfected with N557E‐, H630E‐ or H630L‐BCRP cDNA showed similar degrees of resistance to mitoxantrone and SN‐38. Estrone and fumitremorgin C reversed the drug resistance of cells transfected with R482‐, N557‐ or H630‐mutant BCRP cDNA. Cells transfected with R482G‐ or R482S‐BCRP cDNA showed less intracellular accumulation of [3H]mitoxantrone than the wild‐type BCRP‐transfected cells. These results suggest that E446 in TM2, R482 in TM3, N557 in TM5 and H630 in TM6 play important roles in drug recognition of BCRP. © 2003 Wiley‐Liss, Inc.
Tumor reversion: Correction of malignant behavior by microenvironmental cues
Authors: Kenny Paraic A. , Bissell Mina J.
Published: October 2003

Cancer is characterized by unrestrained proliferation and loss of organization, a process that is intimately linked to, and controlled by, reciprocal signaling between the genetically altered tumor epithelium, the stroma, the components of the basement membrane and inflammatory mediators. Much work has been done to characterize the genetics of cancer cells. In this review, we describe the experiments that have been performed, which point to the significant role of the tissue microenvironment in the developmental regulation of normal and neoplastic cells. Using a variety of model systems, the works of a number of laboratories have converged on a hypothesis where the correction of 1 or 2 signaling defects can revert tumor cells to a normal phenotype, both in vivo and in culture, even when the tumor cells possess multiple genetic and epigenetic lesions. This paradigm has been successfully used to treat acute promyelocytic leukemia, and it remains the task of biomedical researchers to identify additional targets for the reversion of other human malignancies. © 2003 Wiley‐Liss, Inc.
The effect of nitric oxide on cyclooxygenase‐2 (COX‐2) overexpression in head and neck cancer cell lines
Authors: Park Seok‐Woo , Lee Sang‐Goo , Song Sang‐Hyun , Heo Dae‐Seog , Park Bum‐Jung , Lee Dong‐Wook , Kim Kwang‐Hyun , Sung Myung‐Whun
Published: October 2003

The overexpression of cyclooxygenase‐2 (COX‐2) and inducible nitric oxide synthase (iNOS) has been previously reported in head and neck squamous cell carcinoma (HNSCC), as well as in many cancers. We hypothesized that endogenous nitric oxide (NO) might increase the expression of COX‐2 in cancer cells. Therefore, we investigated the cross‐talk between NO and the prostaglandin (PG) pathways in HNSCC cell lines. We found that COX‐2 and iNOS expressions were elevated simultaneously. On adding the NO donor, SNAP, the PGE2 level was increased 2–20 times due to increased COX‐2 expression. This increase of COX‐2 expression by SNAP or PMA (potent inducer of both iNOS and COX‐2) was blocked to various degrees by NO scavengers and NOS inhibitors (L‐NAME and 1400W). Also, the expression of COX‐2 in resting cells was inhibited by NOS inhibitors. Moreover, COX‐2 expression, induced by SNAP, was inhibited by ODQ, a soluble guanylate cyclase (sGC) inhibitor. The effect of dibutyryl‐cGMP on COX‐2 expression was similar to that of SNAP. These results imply that endogenous or exogenous NO activates sGC and that the resulting increase of cGMP induces a signaling that upregulates the expression of COX‐2 in HNSCC cell lines. We also observed that NO increased COX‐2 expression in different cancer cell lines, including cervic and gastric cancer cell lines. These findings further support the notion that NO can be associated with carcinogenesis through the upregulation of COX‐2, and that NOS inhibitor may be also useful for cancer prevention. © 2003 Wiley‐Liss, Inc.
Piroxicam selectively inhibits the growth of premalignant and malignant human oral cell lines by limiting their progression through the S phase and reducing the levels of cyclins and AP‐1
Authors: Ding Haiming , Han Chunhua , Gibson‐D′Ambrosio Ruth , Steele Vernon E. , D′Ambrosio Steven M.
Published: October 2003

Studies have shown that nonsteroidal antiinflammatory drugs (NSAIDs) reduce the risk of and mortality from a variety of cancers. Although cyclooxygenase (COX)‐dependent and ‐independent pathways may be involved, the mechanisms responsible for these effects remain unknown. In our study, we found that piroxicam inhibited cell growth in premalignant and malignant, but not normal, human oral epithelial cell lines in a concentration‐ and time‐dependent manner. After 6 days of exposure, the concentration that inhibited growth by 50% was 181 and 211 μM for premalignant and malignant cells, respectively. Piroxicam did not induce apoptosis. The growth inhibitory effect was COX and PGE2 independent. Adding PGE2 or infecting cells with a COX‐1 transgene did not abrogate piroxicam‐induced growth inhibition. After treatment of the premalignant and malignant cell lines with piroxicam, cells accumulated in the S phase of the cell cycle. Upon removal of piroxicam, cells entered the G2 phase. The S phase block was accompanied by a reduction in the protein levels of cyclin A, cyclin B1, cyclin D1, cdc2, PCNA and the c‐jun AP‐1 component. Therefore, piroxicam may exert its growth inhibitory effects selectively on the premalignant and malignant human oral epithelial cells lines via signaling pathways regulating the progression of cells through the S phase of the cell cycle. © 2003 Wiley‐Liss, Inc.
Adhesive protein interactions with chitosan: Consequences for valve endothelial cell growth on tissue‐engineering materials
Authors: Cuy Janet L. , Beckstead Benjamin L. , Brown Chad D. , Hoffman Allan S. , Giachelli Cecilia M.
Published: October 2003

Stable endothelialization of a tissue‐engineered heart valve is essential for proper valve function, although adhesive characteristics of the native valve endothelial cell (VEC) have rarely been explored. This research evaluated VEC adhesive qualities and attempted to enhance VEC growth on the biopolymer chitosan, a novel tissue‐engineering scaffold material with promising biological and chemical properties. Aortic VEC cultures were isolated and found to preferentially adhere to fibronectin, collagen types IV and I over laminin and osteopontin in a dose‐dependent manner. Seeding of VEC onto comparison substrates revealed VEC growth and morphology to be preferential in the order: tissue culture polystyrene > gelatin, poly(DL‐lactide‐co‐glycolide), chitosan > poly(hydroxy alkanoate). Adhesive protein precoating of chitosan did not significantly enhance VEC growth, despite equivalent protein adsorption as to polystyrene. Initial cell adhesion to protein‐precoated chitosan, however, was higher than for polystyrene. Composite chitosan/collagen type IV films were investigated as an alternative to simple protein precoatings, and were shown to improve VEC growth and morphology over chitosan alone. These findings suggest potential manipulation of chitosan properties to improve amenability to valve tissue‐engineering applications. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 538–547, 2003
Mathematical model of static platelet adhesion on a solid surface
Authors: Vasin Sergei L. , Titushkin Igor A. , Sevastianov Viktor I.
Published: October 2003

The scheme of platelet/surface interaction and a kinetic model of platelet adhesion on a solid surface are suggested. The elaborated approach takes into account the platelet activation by the surface and accumulation of free activated cells in the bulk of the liquid phase. This effect has an especially important role in static experimental conditions. The suggested model explains three types of adhesion kinetic curves, obtained in experiments in vitro: sigmoid curves with or without saturation and an exponential curve with saturation. According to the model, the curve shape is determined by material surface properties, platelet functionality, and experimental conditions of the platelet/surface interaction. The data of static platelet adhesion from platelet rich plasma on glass, siliconized glass, hexadecyltrichlorosilane monolayers, and low‐density polyethylene are described mathematically with the proposed model. Numerical parameters are calculated from approximation of experimental data by the model. These parameters allow quantitative characterization of platelet interaction with the material surface. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 582–590, 2003
Examination of membrane rupture as a mechanism for mammalian cell detachment from fibronectin‐coated biomaterials
Authors: Goldstein Aaron S. , DiMilla Paul A.
Published: October 2003

Synthetic biomaterials intended for the reconstruction of tissues and organs must be capable of sustaining adhesive contact with adjacent cells and tissues under mechanical and hydrodynamic stresses. To facilitate this adhesion, extracellular matrix proteins or peptide sequences are frequently immobilized to the biomaterial interface. These ligands enhance cell attachment by raising the number of cell receptor/ligand interactions, but consequently they may alter the mechanism of cell detachment. In particular, as the cell membrane is more strongly immobilized to the substratum, the tendency for cell detachment to involve membrane rupture may increase. To test this hypothesis, cells were fluorescent stained with a membrane dye, allowed to attach to fibronectin‐coated model substrates for 30 min, and then subjected to a spatially dependent range of shear stress for 5 min (28–220 dyn/cm2) using a radial‐flow chamber. Phase‐contrast and fluorescent images were analyzed to determine the probability for cell detachment and the area of fluorescent debris left by detaching cells as a function of fibronectin concentration, magnitude of shear stress, and time. It was found at all concentrations of fibronectin that the majority of detaching cells left membrane fragments, the mean size of these fragments was independent of shear stress, and the shape independent of the direction of flow. However, mean fragment area increased with concentration of fibronectin and decreased with duration of shearing flow. We postulate that the area of debris reflects the extent of cell attachment prior to the application of shear and that adhesive complexes can disassemble at the onset of flow. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 658–666, 2003
Ca/P ratio effects on the degradation of hydroxyapatite in vitro
Authors: Wang Haibo , Lee Jong‐Kook , Moursi Amr , Lannutti John J.
Published: October 2003

Phase purity is a well‐recognized but not well‐understood variable affecting the biological integration of hydroxyapatite (HA)‐based biomaterials. Minor amounts of specific, relevant impurities—calcium oxide (CaO) and tricalcium phosphate (TCP)—may often be present either as deliberate additions or as a result of decomposition during sintering. We investigated the influence of these two impurities in terms of their effects on surface morphology, weight loss/gain, and microstructural‐level degradation. Phase purity variations were deliberately introduced into an otherwise‐standardized HA matrix—the parent HA grain size and bulk density were relatively constant—produced using identical fabrication conditions. Stability varied markedly during exposure to mildly acidic, neutral, and pH 7.4 phosphate‐buffered saline. Equivalent molar variations in the Ca/P ratio (1.62 vs 1.72) on either side of the stoichiometric ratio produce relatively small volumetric amounts of CaO (1.6 vol%) versus TCP (27 vol%) in HA. However, the relatively small amounts of CaO render the bulk more susceptible to degradation and more likely to have negative effects on a biological milieu. Interestingly, the presence of CaO is also a potent nucleating agent for the precipitation of new surface phases and detectable weight gain. The TCP‐containing ceramic, in contrast, paradoxically exhibited slightly greater resistance to degradation than HA. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 67A: 599–608, 2003
4‐*GDDs(3n) and generalized Steiner systems GS(2, 4, v, 3)
Authors: Ge G. , Wu D.
Published: October 2003

Generalized Steiner systems GS(2, k, v, g) were first introduced by Etzion and used to construct optimal constant weight codes over an alphabet of size g + 1 with minimum Hamming distance 2k − 3, in which each codeword has length v and weight k. As to the existence of a GS(2, k, v, g), a lot of work has been done for k = 3, while not so much is known for k = 4. The notion k‐*GDD was first introduced and used to construct GS(2, 3, v, 6). In this paper, singular indirect product (SIP) construction for GDDs is modified to construct GS(2, 4, v, g) via 4‐*GDDs. Furthermore, it is proved that the necessary conditions for the existence of a 4‐*GDD(3n), namely, n ≡ 0, 1 (mod 4) and n ≥ 8 are also sufficient. The known results on the existence of a GS(2, 4, v, 3) are then extended. © 2003 Wiley Periodicals, Inc. J Combin Designs 11: 381–393, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jcd.10047
A Kiosk WWW browser for digital museums
Authors: Shigesada Yukihiko , Koshizuka Noboru , Sakamura Ken
Published: October 2003

One of the recent general tendencies in the museums is a display explanation method in which the explanation is constructed as digital content on the WWW, and the visitor views the content through a public terminal called a “kiosk terminal” installed at the display site. However, when existing WWW browsers are used in kiosk terminals and are operated by diverse users, various inconveniences result, since the user interface is designed for the individual user. We therefore constructed a new type of browser called BKB (BTRON Kiosk Browser), which has the function of presenting WWW content through a user interface suited to the kiosk terminal. This paper first surveys the technical issues of providing WWW content through the BKB user interface. Then, user interface techniques for BKB are proposed in order to solve the problems. Implementation techniques for the functions proposed by us are described. © 2003 Wiley Periodicals, Inc. Syst Comp Jpn, 34(13): 59–70, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10303
A method of discrimination and scoring of aspirated and unaspirated sounds for Chinese spoken language learning system
Authors: Tian Jiapeng , Miwa Jouji
Published: October 2003

To support the construction of a Chinese spoken language self‐instruction system, we propose a discrimination method that uses the dynamic low‐pass power (DLP) as the feature quantity for automatic discrimination between aspirated and unaspirated sounds, which is an important problem in Chinese pronunciation education. We also propose a scoring method based on the a posteriori probability of the feature quantity. In an open experiment in which the speech data of five Chinese native speakers other than the training speaker were discriminated, the results show that a discrimination rate of 95.4% was obtained for aspirated sounds and 97.5% for unaspirated sounds. For the speech data of six Japanese learners, an average coincidence rate of 95.2% between the perception result and the system discrimination result was achieved. We have also performed the scoring of the pronunciation by the learner and evaluated its quality, demonstrating the possibility of constructing a real system. © 2003 Wiley Periodicals, Inc. Syst Comp Jpn, 34(14): 44–53, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10368
A multilayer neural network with pulse position modulation
Authors: Hikawa Hiroomi
Published: October 2003

The problem of the pulse mode neural network is that the synapse weight is bounded between +1 and −1. In order to enhance the weight range, this paper proposes a new weighting method that is a combination of pulse density modulation and pulse position modulation (PPM). The feasibility of the proposed method is verified by experimental MNN with on‐chip learning. A modified back‐propagation algorithm is used for the on‐chip learning. The experimental results show that the proposed MNN architecture has the ability to handle high‐resolution classifying problems and good on‐chip learning capability. © 2003 Wiley Periodicals, Inc. Syst Comp Jpn, 34(13): 36–46, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10474
Robust line fitting using LMedS clustering
Authors: Inui Kentaro , Kaneko Shun'ichi , Igarashi Satoru
Published: October 2003

The authors propose a robust clustering method based on the Least Median of Squares principle. This is a general‐purpose method, and is efficient for finding a majority structure using dictionary sorting and a smallest square region enclosing for a set of data points. In addition, the authors propose a robust line fitting algorithm using this method. The fitting problem is solved through a dual transform of a pair of points selected from data space to a parameter space, and then clustering the mapped points. Moreover, a function to identify outliers based on the size of the square region converging in the parameter space is defined, and is used to distinguish between normal values and outliers. The proposed method enables robust line fitting for data points found in images or in files. The resulting line statistically satisfies the least median condition. Furthermore, line fitting to groups of points with a high outlier percentage is also possible. Here, outliers and normal values are removed in sequence. The validity of the proposed method has been shown based on the results of simulation experiments. © 2003 Wiley Periodicals, Inc. Syst Comp Jpn, 34(14): 92–100, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.1225
Bacterial lipopolysaccharide modulates Protein Kinase C signalling in Lymnaea stagnalis haemocytes
Authors: Walker Anthony J. , Plows Louise D.
Published: October 2003

Our knowledge of cell signalling pathways in the molluscan immune system and their response to immunological challenge is currently poor. The present study focused on the Protein Kinase C (PKC) pathway in the immune cells (haemocytes) of Lymnaea stagnalis and its response following exposure to bacterial lipopolysaccharide (LPS). Western blotting of haemocyte proteins with either anti‐PKC (pan) or anti‐phospho‐PKC (Ser 660) antibodies revealed the presence of two PKC‐like immuno‐reactive proteins of approximately 76 and 85 kDa. Challenge of haemocytes with LPS transiently increased the phosphorylation of the 85 kDa isoform, with a 2.2‐fold increase in phosphorylation levels at 5 min and a return to basal levels after 20 min. This LPS‐mediated response was blocked following treatment of haemocytes with GF109203X. PKC activities measured in anti‐phospho‐PKC immunocomplexes following haemocyte treatment with LPS and GF109203X correlated well with the observed PKC phosphorylation levels. These data show for the first time that the activity of the PKC pathway in molluscan immune cells is modulated by LPS, as it is in mammals, and suggest that cell signalling in the innate immune response may have been conserved through evolution.
Role of the kinase activation loop on protein kinase C θ activity and intracellular localisation
Authors: Sparatore Bianca , Passalacqua Mario , Pedrazzi Marco , Ledda Sabina , Patrone Mauro , Gaggero Deborah , Pontremoli Sandro , Melloni Edon
Published: October 2003

Multiple protein kinase C (PKC) θ species, identified in an erythroleukaemia cell line, have been characterised in terms of their molecular properties and intracellular distribution. PKCθs localised in the detergent‐soluble cell fraction have an M
r of 76 kDa (θ‐76) and contain Thr538 or pThr538 in the kinase activation loop. In contrast, PKCθs localised in the Golgi complex have an M
r of 85 kDa (θ‐85) and, although unphosphorylated at Thr538, are catalytically active. Strikingly, only θ‐76 species which are unphosphorylated at Thr538 can undergo autocatalytic conversion to θ‐85. Moreover, a Thr538→Ala PKCθ mutant is constitutively localised in the Golgi complex, confirming that changes in the phosphorylation state of this residue play a pivotal role in the overall control of catalytic properties and localisation of this kinase.
In search of the prototype of nitric oxide synthase
Authors: Zemojtel Tomasz , Wade Rebecca C , Dandekar Thomas
Published: October 2003

Recent identification of the prokaryotic genes related to the catalytic oxygenase domain of mammalian nitric oxide synthase (NOS) has led to speculations on the origins of the NO signaling network. NOS activity in eukaryotes relies on the concerted action of the oxygenase domain with an electron‐donating reductase domain that is fused to it. A fused reductase domain is, however, absent in prokaryotes. Consequently, we searched bacterial genomes for homologs of the reductase domain and identified candidate genes. On the basis of genomic sequence and protein structural analysis, we here propose that sulfite reductase flavoprotein is a prototype of the mammalian NOS reductase domain and a complementing interaction partner of the bacterial NOS oxygenase protein.
Methylation at CpG islands in intron 1 of EGR2 confers enhancer‐like activity
Authors: Unoki Motoko , Nakamura Yusuke
Published: October 2003

We previously demonstrated several lines of evidence indicating that early growth response 2 (EGR2) functions as a tumor suppressor, partly on the basis that its expression was often decreased in human tumors and cancer cell lines. Here we report a possible molecular mechanism to account for down‐regulation of EGR2 in tumor cells. Although no genetic mutations in the gene or alterations in methylation status of its promoter were detected, we found a high degree of methylation at CpG islands in intron 1 of EGR2 in cell lines that were expressing this gene at a high level. Moreover, reporter gene experiments revealed that methylated intron 1 had somehow conferred enhancer‐like activity. The data imply the existence of a previously unsuspected mechanism of gene expression regulation.
Interactions between NADPH oxidase and voltage‐gated proton channels: why electron transport depends on proton transport
Authors: DeCoursey Thomas E
Published: October 2003

Leukocytes kill microbes by producing reactive oxygen species, using a multi‐component enzyme complex, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Electrons pass from intracellular NADPH through a redox chain within the enzyme, to reduce extracellular O2 to O2
−. Electron flux is electrogenic, and rapidly depolarizes the membrane potential. Excessive depolarization can turn off electron transport by self‐inhibition, but this is prevented by proton flux that balances the electron flux. Although the membrane potential depolarizes by ∼100 mV during the respiratory burst (NADPH oxidase activity), NADPH oxidase activity is independent of voltage in this range, which permits optimal function and prevents self‐inhibition.
Membrane protein reconstitution and crystallization by controlled dilution
Authors: Rémigy H.-W , Caujolle-Bert D , Suda K , Schenk A , Chami M , Engel A
Published: October 2003

Efficient reconstitution of membrane proteins for functional analyses can be achieved by dilution of a ternary mixture containing proteins, lipids and detergents. Once the dilution reaches the point where the free detergent concentration would become lower than the critical micellar concentration, detergent is recruited from the bound detergent pool, and association of proteins and lipids is initiated. Here we show that dilution is also suitable for the assembly of two‐dimensional crystals. A device has been designed that allows controlled dilution of a protein–lipid–detergent mixture to induce formation of densely packed or crystalline proteoliposomes. Turbidity is used to monitor the progress of reconstitution on‐line, while dilution is achieved by computer‐controlled addition of buffer solution in sub‐microliter steps. This system has mainly been tested with porin OmpF, a typical β‐barrel protein, and aquaporin‐1, a typical α‐helical protein. The results demonstrate that large, highly ordered two‐dimensional crystals can be produced by the dilution method.
Membrane protein folding: beyond the two stage model
Authors: Engelman Donald M. , Chen Yang , Chin Chen-Ni , Curran A.Rachael , Dixon Ann M. , Dupuy Allison D. , Lee Albert S. , Lehnert Ursula , Matthews Erin E. , Reshetnyak Yana K. , Senes Alessandro , Popot Jean-Luc
Published: October 2003

The folding of α‐helical membrane proteins has previously been described using the two stage model, in which the membrane insertion of independently stable α‐helices is followed by their mutual interactions within the membrane to give higher order folding and oligomerization. Given recent advances in our understanding of membrane protein structure it has become apparent that in some cases the model may not fully represent the folding process. Here we present a three stage model which gives considerations to ligand binding, folding of extramembranous loops, insertion of peripheral domains and the formation of quaternary structure.
Dab2 links CIN85 with clathrin‐mediated receptor internalization
Authors: Kowanetz Katarzyna , Terzic Janos , Dikic Ivan
Published: October 2003

CIN85 is a multidomain scaffold protein involved in downregulation of receptor tyrosine kinases. Here we show that disabled‐2 (Dab2), an endocytic adaptor molecule implicated in clathrin‐coat assembly, associates with CIN85 in mammalian cells. All three SH3 domains of CIN85 were able to bind to the PKPAPR peptide in the carboxyl‐terminal part of Dab2, possibly enabling CIN85 to simultaneously interact with multiple Dab2 molecules. CIN85 association with Dab2 is essential for its recruitment to clathrin coat and appears to be modulated by growth factor stimulation. Dab2 and clathrin dissociated from CIN85 following growth factor treatment, enabling other molecules, such as Cbl, to bind to CIN85. Taken together, our data indicate a dynamic interplay between CIN85 and its effectors during endocytosis of receptor tyrosine kinases.
Improved regional left ventricular function after successful satellite cell grafting in rabbits with myocardial infarction
Authors: Blatt Alex , Robinson Dror , Cotter Gad , Efrati Shai , Simantov Yariv , Bar Ilan , Kaluski Edo , Krakover Ricardo , Sidenko Stanislav , Evron Zoharia , Lipa Lidia , Posternak Natalia , Nevo Zvi , Vered Zvi
Published: October 2003

Objective:

To evaluate whether satellite cells injected into infarct areas in rabbits remain viable during 6 weeks follow‐up and can improve cardiac function as assessed by echocardiography.

Methods:

Myocardial infarction was induced in 16 New Zealand white rabbits, by ligation of the marginalis sinistra artery. Tissue from gluteus muscle biopsies was dissected into small pieces and cultured. Within 2–3 weeks the cells were expanded by 2–3 orders of magnitude and were fluorescent labeled. Single cell pellets for resuspension at >106/1 ml were directly injected into the infarct areas in 8 rabbits. In 8 additional rabbits, 1 ml saline was injected (control). Regional left ventricular function was assessed weekly by 2‐D echocardiography until animals were sacrificed. Analysis was performed blind and independently by two experienced echocardiographers, based on the American Society of Echocardiography scheme.

Results and discussion:

Six treated and five control rabbits completed the study. One week after the artery occlusion, left ventricular function scoring did not differ between groups, mean 8.7±1.6 vs 8.3±1.9 (P=0.74). At 6 weeks post‐injection, echocardiographic score was significantly better in the treated group, mean 2.6±0.9 vs 6.9±2.1 (P=0.002). The treated group showed significant gradual segmental improvement between the first week up to week 6. After sacrifice, macro and microscopic transmural areas showed typical changes of myocardial infarction. Histochemical staining identified viable grafted cells in high density 6 weeks post‐transplantation in all grafted hearts.

Conclusion:

Autologous satellite cells (skeletal myofiber), can be successfully grafted into rabbit hearts following myocardial infarction and may induce improved regional left ventricular function.
Instruments to measure acceptability of information and acquisition of knowledge in patients with heart failure
Authors: Gwadry‐Sridhar Femida , Guyatt Gordon H. , Arnold J. Malcolm O. , Massel David , Brown Jim , Nadeau Lorraine , Lawrence Sharon
Published: October 2003

Background:

Patients with heart failure suffer from poor health outcomes and require combinations of medications to treat their disease. Providing patients with knowledge through education is one mechanism to help them improve compliance with complicated treatment regimens.

Methods:

We developed and tested two instruments. The first instrument, which we call the measure of educational material acceptability (EMA), was designed to help us differentiate between written educational materials according to patients’ subjective responses. The second instrument, the knowledge acquisition questionnaire (KAQ), which measures knowledge gained, was designed to determine whether patients understand the rationale and mechanics of their heart failure management. We explored the measurement properties of both instruments.

Results:

The internal consistency of the EMA was 0.79 (Cronbach's alpha). The internal consistency of the KAQ was 0.61 and its responsiveness, measured using change scores of knowledge before and after an educational intervention, was 0.75.

Conclusions:

We have developed instruments that measure acceptability and knowledge acquisition, and that clinicians and investigators involved in heart failure programs may find useful in developing educational material and measuring the impact of their interventions on patients’ knowledge.
Congestive heart failure with preserved left ventricular systolic function after acute myocardial infarction: clinical and prognostic implications
Authors: Møller Jacob Eifer , Brendorp Bente , Ottesen Michael , Køber Lars , Egstrup Kenneth , Poulsen Steen Hvitfelt , Torp‐Pedersen Christian
Published: October 2003

Aims:

To characterise the prevalence, in‐hospital complications, management, and long‐term outcome of patients with congestive heart failure but preserved left ventricular systolic function after acute myocardial infarction.

Methods:

3166 consecutive patients screened for entry in the Bucindolol Evaluation in Acute Myocardial Infarction Trial with definite acute myocardial infarction and echocardiographic assessment of left ventricular systolic function were included between 1998 and 1999 in this prospective observational study. Main outcome measures were occurrences of in‐hospital complications and all cause mortality.

Results:

Congestive heart failure was seen during hospitalisation in 1464 patients (46%), 717 patients had preserved left ventricular systolic function (wall motion index ≥1.3 corresponding to ejection fraction ≥0.40), and 732 patients had systolic dysfunction (wall motion index <1.3). One year mortality in patients with no heart failure, heart failure with preserved systolic function, and heart failure with systolic dysfunction were 6, 22 and 35%, P<0.0001. Unadjusted risk of death from all causes associated with heart failure and preserved systolic function was 3.3 (95% CI 2.8–4.0), and after adjustment for baseline characteristics and left ventricular systolic function in multivariate Cox proportional hazards analysis the risk was 2.1 (95% CI 1.7–2.6), P<0.0001.

Conclusions:

Congestive heart failure is frequently present in patients with preserved left ventricular systolic function, and is associated with increased risk of in‐hospital complications and death following acute myocardial infarction.
STATE IMMUNITY OUTSIDE THE STATE IMMUNITY ACT
Authors: Yang Xiaodong
Published: October 2003

IS the State Immunity Act 1978 the sole basis for deciding on State immunity? It is and it is not. This seemingly self-contradictory reply is due to the fact that, on the one hand, any proceedings directly or indirectly against a foreign State must be brought under the 1978 Act while, on the other, certain provisions of that Act might paradoxically render the Act itself inapplicable and therefore entail recourse to rules outside the Act for settling the issue of State immunity. This is amply illustrated by the decision of the House of Lords in Holland v. Lampen-Wolfe [2000] 1 W.L.R. 1573, which involved a claim for defamation brought by a US university professor teaching international relations at a US military base in England as part of an education programme provided by her university under a commercial agreement with the US Government. The claim was brought against the education services officer at the base, who had written a memorandum listing serious complaints about the plaintiff’s performance and questioning her professional competence. The US Government claimed immunity on the defendant’s behalf.
THE ‘BABY-DRY’ CASE: THE MODERNISATION OF TRADE MARKS?
Authors: Davis Jennifer
Published: October 2003

WHEN is a monopoly not a monopoly? Following the decision of the European Court of Justice in Case C-383/99 P Procter & Gamble v. Office for Harmonisation of the Internal Market (OHIM) [2002] E.T.M.R. 3, the answer appears to be when it is a registered trade mark.
Multi-Party Actions. By Christopher Hodges. [Oxford: Oxford University Press. 2001. xlii, 503 and (Appendices) 39 pp. Hardback £95 net. ISBN 0–19–829896–X.]
Authors: Andrews Neil
Published: October 2003

This is an excellent addition to the Oxford series of works on litigation. The main author is a London solicitor with a commercial practice (but also a part-time academic). He has assembled a team of English and foreign specialist lawyers. The book is aimed at practitioners, but the author has not eschewed critical and theoretical literature. Overall, Hodges has produced a minor miracle: a book which is useful, comprehensive, accurate, up-to-date, stimulating and outward-looking. The book is also handsomely produced. It is hoped that a second edition might include a bibliography and perhaps paragraph headings throughout the text. It is also suggested that discussion of representative proceedings (see below) and of the American class action might be expanded.
The Resilience of Guanxi and its New Deployments: A Critique of Some New Guanxi Scholarship
Authors: Yang Mayfair Mei-hui
Published: October 2003

In addressing claims that the art of guanxi is declining in China's current incorporation of capitalism, this article argues that guanxi must be treated historically as a repertoire of cultural patterns and resources which are continuously transformed in their adaptation to, as well as shaping of, new social institutions and structures, and by the particular Chinese experience with globalization. The article takes issue with approaches which treat guanxi as a fixed essentialized phenomenon which can only wither away with the onslaught of new legal and commercial regimes. Rather, as the examples of Taiwan and post-socialist Russia's encounter with capitalism suggest, guanxi practice may decline in some social domains, but find new areas to flourish, such as business transactions, and display new social forms and expressions. This historical approach to guanxi, which is sensitive to issues of power both within the Chinese social order and between China and the West, is especially critical of the unreflective positivist methodology and the teleology of modernization theory/narrative and neo-liberal discourse embedded in the argument for the decline of guanxi.
Tackling Cross-border Environmental Problems in Hong Kong: Initial Responses and Institutional Constraints
Authors: Lee Yok-shiu F.
Published: October 2003

With rapid industrial and urban growth taking place across the border, there has been a marked increase in public concern in Hong Kong over cross-border environmental problems since the early 1990s. Despite this increased concern, however, very little systematic research has been conducted on the issue. This article addresses the question of how, and to what extent, the SAR government could work with various jurisdictions across the border to address cross-border environmental problems within the “one country, two systems” governance framework. It concludes on a pessimistic note by pointing out that current signs strongly suggest that the SAR government is even more pro-business than the colonial government. Coupled with China's fragmented environmental governance structure and a dominant pro-growth culture permeating the delta region, all indications point to an uphill and long drawn-out battle for environmental managers on both sides of the border to bring forth improvements in this fast-growing and continually deteriorating landscape.