bluuebunny/crossref_metadata_2025_split huggingface dataset:
Alterations in tropomyosin isoform expression in human transitional cell carcinoma of the urinary bladder
Authors: Pawlak Geraldine , McGarvey Terence W. , Nguyen Trang B. , Tomaszewski John E. , Puthiyaveettil Raghunath , Malkowicz S. Bruce , Helfman David M. 
Published: March 2004

AbstractPrevious studies of transformed rodent fibroblasts have suggested that specific isoforms of the actin‐binding protein tropomyosin (TM) could function as suppressors of transformation, but an analysis of TM expression in patient tumor tissue is limited. The purpose of our study was to characterize expression of the different TM isoforms in human transitional cell carcinoma of the urinary bladder by immunohistochemistry and Western blot analysis. We found that TM1 and TM2 protein levels were markedly reduced and showed >60% reduction in 61% and 55% of tumor samples, respectively. TM5, which was expressed at very low levels in normal bladder mucosa, exhibited aberrant expression in 91% of tumor specimens. The Western blot findings were confirmed by immunohistochemical analysis in a number of tumors. We then investigated the mechanism underlying TM expression deregulation, in the T24 human bladder cancer cell line. We showed that levels of TM1, TM2 and TM3 are reduced in T24 cells, but significantly upregulated by inhibition of the mitogen‐activated protein kinase‐signaling pathway. In addition, inhibition of this pathway was accompanied by restoration of stress fibers. Overall, changes in TM expression levels seem to be an early event during bladder carcinogenesis. We conclude that alterations in TM isoform expression may provide further insight into malignant transformation in transitional cell carcinomas of the bladder and may be a useful target for early detection strategies. © 2004 Wiley‐Liss, Inc.
Using modelling to improve operational performance in the Cu Chi irrigation system, Vietnam
Authors: George Biju A. , Malano Hector M. , Tri Vo Khac , Turral Hugh 
Published: March 2004

AbstractThe Cu Chi irrigation system in Vietnam forms part of the Dau Tieng reservoir system in the Dong Nai basin. Water competition in this system is intensifying as a result of increasing urban and environmental demand. System operation modelling using the Irrigation Main System OPeration (IMSOP) model was applied to the Cu Chi irrigation system, Vietnam, to improve its operational performance. The operation improvement process involved the comparison of supply and demand during two years, 2001 and 2002, revealing that the system's operation was carried out without consideration of the crop water demand and proper canal regulation. The retrospective operational analysis revealed a substantial amount of oversupply and inequity of distribution. Two new operation strategies were selected after a simulation analysis and evaluated in the field. The new scenarios showed a more equitable distribution of water in the system. The average pre‐intervention supply–demand ratio which ranged from 1.68 to 2.51 was reduced to 1.20 for continuous flow and 1.17 for rotational operation. A comprehensive analysis of water reallocation to Ho Chi Minh City for urban and industrial purposes and its effect on the security of supply on the Cu Chi system was also undertaken. Copyright © 2004 John Wiley & Sons, Ltd.
l‐Arginine ameliorates oxidative stress in alloxan‐induced experimental diabetes mellitus
Authors: El‐Missiry M. A. , Othman A. I. , Amer M. A. 
Published: March 2004

AbstractOxidative stress occurs in diabetic patients and experimental models of diabetes. The ability ofl‐arginine to ameliorate the oxidative stress and metabolic changes after treatment with alloxan was investigated in rats. Adult male rats were injected intraperitoneally with 100 mg kg−1of alloxan to produce experimental oxidative stress characteristic of diabetes mellitus. Hyperglycaemia and hypercholesterolaemia were observed in serum after 7 days of alloxan treatment. This was associated with a depression of glutathione (GSH) concentration as well as superoxide dismutase (SOD) and catalase (CAT) activities in the liver and brain. In addition, the thiobarbituric acid‐reactive substances (TBARS) were significantly elevated, indicating increased lipid peroxidation and oxidative stress in the same tissues. Administration of 100 mg kg−1l‐arginine for 7 days either before or after alloxan injection significantly ameliorated the oxidative stress evidenced by a lower TBARS and a higher level of the endogenous GSH concentration and SOD and CAT activities than alloxan‐treated rats. These effects were paralleled by marked protection and partial prophylaxis against alloxan‐induced hyperglycaemia and cholesterolaemia. Thus, these results showed that exogenously administeredl‐arginine might improve the clinical manifestation of diabetes mellitus and decrease the oxidative stress in the liver and brain. In addition, the study supports the beneficial effect ofl‐arginine, which might be attributed to its direct, NO‐dependent antioxidant capacity and/or NO‐independent pathways. Copyright © 2004 John Wiley & Sons, Ltd.
Glioma cell antioxidant capacity relative to reactive oxygen species produced by dopamine
Authors: Mazzio Elizabeth A. , Soliman Karam F. A. 
Published: March 2004

AbstractThe pathology of Parkinson's disease involves oxidative damage to dopaminergic neurons of the substantia nigra. Oxidation of the dopamine (DA) neurotransmitter itself may contribute to the generation of a reactive oxygen species (ROS) and subsequent neurodegeneration. Glia cells can either exacerbate injury or exert protective properties on local neurons in the brain. We investigate glial antioxidant enzyme systems relative to ROS generated during cytokine activation, monoamine oxidase (MAO) activity and autoxidation of DA in glioma cells. Rat C6 glioma cells stimulated with lipopolysaccharide Escherichia coli 0111:B4 and interferon gamma (LPS/IFN‐g) produced high levels of nitric oxide (241 nmol mg−1 protein 24 h−1) but not superoxide (O−2) or hydrogen peroxide (H2O2). Basal C6 cells exhibited a rapid and robust capacity to remove exogenous H2O2 within minutes. Preincubation with sodium azide but not buthionine‐[S, R]‐sulfoximine attenuated this response, indicating catalase as the primary enzyme responsible for this effect. The glioma catalase reaction rate was slightly attenuated by exposure to LPS/IFN‐g for 24 h. However, the reduction in catalase activity was not due to nitric oxide, because both the supernatant and sodium nitroprusside had no effect on isolated catalase enzyme activity. Hydrogen peroxide was produced only through substrate‐driven MAO activity in prepared lysate. However, the quantity of H2O2 produced per unit time (0.46 nmol mg−1 protein min−1) was negligible compared with the enormous capacity for its removal by catalase (213.9 nmol mg−1 protein min−1) (≥462× greater). Similarly, H2O2 generated by DA autoxidation per unit time (0.28 nmol mg−1 protein equiv. min−1), was rapidly dissolved by glioma cells at high capacity (≥750× greater). In conclusion, C6 cells produce nitric oxide under cytokine/endotoxin‐stimulated conditions. Moreover, C6 cells exhibit a dynamic H2O2 scavenging capacity, with ample facility to dispose of the peroxide generated by both MAO activity and spontaneous DA autoxidation. Copyright © 2004 John Wiley & Sons, Ltd.
Amelioration of sulfur mustard skin injury following a topical treatment with a mixture of a steroid and a NSAID
Authors: Dachir Shlomit , Fishbeine Eliezer , Meshulam Yakov , Sahar Rita , Chapman Shira , Amir Adina , Kadar Tamar 
Published: March 2004

AbstractThe ability to ameliorate sulfur mustard (HD)‐induced oedema by treatment with anti‐inflammatory drugs was reported previously after screening four steroids and four non‐steroidal anti‐inflammatory drugs (NSAIDs) using the mouse ear vesicant model. Following the screening study, one steroid and one NSAID (Adexone and Voltaren) were selected as the most effective, and a mixture of the two was chosen for the present more extensive research. The effect of the combined treatment on clinical, biochemical and histopathological parameters following HD insult was studied. Mice ears were exposed to 0.2 µl of HD for 10 min to produce a moderate skin injury. Oedema development peaked ca. 48 h following exposure, as determined by weighing ear biopsies. Histological observations at that time exhibited damage to the epidermis and dermis. An increase in prostaglandin E (PGE) was measured in skin homogenates, starting 8 h following exposure and lasting at least up to 48 h post‐exposure.A topical treatment using the above anti‐inflammatory mixture significantly reduced inflammatory parameters when applied up to 4 h following exposure. These parameters included extent of oedema, levels of PGE, area of clinical damage and extent of cytotoxic injury (vesications and damaged epithelial cells).Thus, a combination of a steroid and NSAID was found to be effective in reducing the intensity of HD skin injury and possibly shortening the time to full recovery. The treatment, however, did not prevent completely the ensuing cytotoxic processes in the epithelial layer. Copyright © 2004 John Wiley & Sons, Ltd.
In vivo exposure of Dreissena polymorpha mussels to the quinones menadione and lawsone: menadione is more toxic to mussels than lawsone
Authors: Osman A. M. , Rotteveel S. , den Besten P. J. , van Noort P. C. M. 
Published: March 2004

AbstractThe principal aim of this study was to assess whether the two quinones, menadione (2‐methyl‐1,4‐naphthoquinone) and lawsone (2‐hydroxy‐1,4‐naphthoquinone), elicit differential toxicity in mussels as has been reported for higher organisms. Therefore, the effects of short‐term (48 h) and long‐term (20 days) exposure of the two quinones at concentrations of 0.56 and 1 mg l−1 to zebra mussels, Dreissena polymorpha, under laboratory conditions were studied. After the short‐term exposure, the specific activities of the two‐electron quinone oxidoreductase (DT‐diaphorase) and the one‐electron catalysing quinone reductases NADPH‐cytochrome c reductase and NADH‐cytochrome c reductase were determined in the gills and the rest of the soft tissues (soft mussel tissues minus the gills) of both treated and control mussels. At the higher concentrations of menadione and lawsone used, a significant reduction of the activity of NADPH‐cytochrome c reductase in the gills and in the rest of the soft mussel tissues (by 33–34% and 31–43%, respectively) was observed. The activities of DT‐diaphorase and NADH‐cytochrome c reductase were not significantly affected.Interestingly, DT‐diaphorase was observed in the gills, an organ requiring protection against antioxidants. Furthermore, a single‐cell electrophoretic assay (comet assay) performed with gill cells to assess DNA damage by the quinones did not show any significant difference between the treated and the control organisms. This indicates that the formation of reactive species by the quinone metabolism in vivo in the mussels was possibly suppressed through the concerted action of DT‐diaphorase and antioxidant enzymes. The results of in vitro experiments with gill extracts confirmed the protective role of DT‐diaphorase. The rate of the two‐electron quinone reduction was found to be five times that of the one‐electron quinone reduction.The results of the long‐term exposure unambiguously demonstrated that in mussels menadione, unlike in higher organisms, is more toxic than lawsone. The lack of detectability of xanthine oxidase in the mussel tissues could explain the comparatively lower toxicity of lawsone in the invertebtrate, lending support to a previous suggestion that xanthine oxidase might be responsible for the mechanism of toxicity of lawsone in higher organisms in vivo. Copyright © 2004 John Wiley & Sons, Ltd.
In vitro protection of plasma cholinesterases by metoclopramide from inhibition by mipafox
Authors: Petroianu G. , Kühn F. , Arafat K. , Zuleger K. , Missler A. 
Published: March 2004

AbstractMetoclopramide (MCP) is a dopamine receptor antagonist and serotonin receptor agonist widely used as an antiemetic and gastric prokinetic drug. In addition MCP is a reversible inhibitor of cholinesterases from human central nervous system and blood. Metoclopramide may have a cholinesterase protective effect against inhibition by organophosphates. The purpose of the study was to quantify in vitro, by means of the ic50 shift, the extent of MCP conferred protection, using mipafox (MPFX) as an inhibitor. Mipafox is a neuropathic organophosphate. Cholinesterase activities (with acetylthiocholine [ChE‐A] and butyrylthiocholine [ChE‐B] as substrates) in human plasma were measured photometrically in the presence of different MPFX concentrations and the ic50 was calculated. Determinations were repeated in the presence of increasing MCP concentrations. It appears that the shift induced by the presence of MCP increases with the MCP concentration in a linear manner. In the presence of a clinically easily achievable plasma concentration of 1 µM MCP, the ic50 of MPFX for cholinesterase ‘shifts’ by a factor of ca. 3–6. The protective effect of MCP on cholinesterase could be of practical relevance in the treatment of organophosphate poisoning. We conclude that in vivo testing of MCP as an organophosphate protective agent is warranted. Copyright © 2004 John Wiley & Sons, Ltd.
Existence question for difference families and construction of some new families
Authors: Martínez Luis , Ðoković Dragomir Z̆. , Vera‐López Antonio 
Published: March 2004

AbstractWe establish some properties of mixed difference families. We obtain some criteria for the existence of such families and a special kind of multipliers. Several methods are presented for the construction of difference families by using cyclotomy and genetic algorithms. © 2004 Wiley Periodicals, Inc. J Combin Designs 12: 256–270, 2004.
Drug‐resistant breast carcinoma (MCF‐7) cells are paradoxically sensitive to apoptosis
Authors: Chen Jack S.K. , Konopleva Marina , Andreeff Michael , Multani Asha S. , Pathak Sen , Mehta Kapil 
Published: March 2004

AbstractThe purpose of this study was to determine whether expression of tissue transglutaminase (TG2) and caspase‐3 proteins in drug‐resistant breast carcinoma MCF‐7/DOX cells would render these cells selectively susceptible to apoptotic stimuli. Despite high resistance to multidrug resistance (MDR)‐related drug, doxorubicin (≥150‐fold), the MCF‐7/DOX cells were extremely sensitive to apoptotic stimuli. Thus, calcium ionophore, A23187 (A23187) and the protein kinase C inhibitor staurosporine (STS) each induced rapid and time‐dependent apoptosis in MCF‐7/DOX cells. The apoptosis induced by either agent was accompanied by caspase‐3 activation and other downstream changes that are typical of cells undergoing apoptosis. The alterations upstream of caspase‐3 activation, however, such as loss in mitochondrial membrane potential (ΔΨ), release of cytochrome c, and activation of caspase‐8, and caspase‐9, were detected only in STS‐treated cells. The A12387 failed to induce any of the caspase‐3 upstream changes, implying that A23187‐induced apoptosis may utilize one or more novel upstream pathways leading to the activation of caspase 3. In summary, these data demonstrate that MCF‐7/DOX cells are much more sensitive to apoptotic stimuli than previously thought and that A23187‐induced apoptosis may involve some novel, yet unidentified, upstream pathway that leads to the activation of caspase‐3 and other downstream events. © 2004 Wiley‐Liss, Inc.
Excision of Sleeping Beauty transposons: parameters and applications to gene therapy
Authors: Liu Geyi , Aronovich Elena L. , Cui Zongbin , Whitley Chester B. , Hackett Perry B. 
Published: March 2004

AbstractA major problem in gene therapy is the determination of the rates at which gene transfer has occurred. Our work has focused on applications of the Sleeping Beauty (SB) transposon system as a non‐viral vector for gene therapy. Excision of a transposon from a donor molecule and its integration into a cellular chromosome are catalyzed by SB transposase. In this study, we used a plasmid‐based excision assay to study the excision step of transposition. We used the excision assay to evaluate the importance of various sequences that border the sites of excision inside and outside the transposon in order to determine the most active sequences for transposition from a donor plasmid. These findings together with our previous results in transposase binding to the terminal repeats suggest that the sequences in the transposon‐junction of SB are involved in steps subsequent to DNA binding but before excision, and that they may have a role in transposase–transposon interaction. We found that SB transposons leave characteristically different footprints at excision sites in different cell types, suggesting that alternative repair machineries operate in concert with transposition. Most importantly, we found that the rates of excision correlate with the rates of transposition. We used this finding to assess transposition in livers of mice that were injected with the SB transposon and transposase. The excision assay appears to be a relatively quick and easy method to optimize protocols for delivery of genes in SB transposons to mammalian chromosomes in living animals. Copyright © 2004 John Wiley & Sons, Ltd.
Genetic engineering of cytolytic T lymphocytes for adoptive T‐cell therapy of neuroblastoma
Authors: Gonzalez Sergio , Naranjo Araceli , Serrano Lisa M. , Chang Wen‐Chung , Wright Christine L. , Jensen Michael C. 
Published: March 2004

AbstractBackgroundDisease relapse is the leading cause of mortality for children diagnosed with disseminated neuroblastoma. The adoptive transfer of tumor‐specific T cells is an attractive approach to target minimal residual disease following conventional therapies. We describe here the genetic engineering of human cytotoxic T lymphocytes (CTL) to express a chimeric immunoreceptor for re‐directed HLA‐independent recognition of neuroblastoma.MethodsThe CE7R chimeric immunoreceptor was constructed by PCR splice overlap extension and is composed of a single‐chain antibody extracellular domain (scFv) derived from the L1‐CAM‐specific murine CE7 hybridoma fused to human IgG1 hinge‐Fc, the transmembrane portion of human CD4, and the cytoplasmic tail of huCD3‐ζ chain (scFvFc:ζ). Primary human T cells were genetically modified by naked DNA electrotransfer of plasmid expression vector CE7R‐pMG then analyzed by Western blotting, flow cytometry for CE7R expression and cell surface trafficking, 4‐h chromium release assay for re‐directed neuroblastoma lysis, and ELISA for tumor‐specific activation of cytokine production.ResultsCE7R is expressed as an intact chimeric protein that trafficks to the cell surface as a type I transmembrane protein. Primary human CE7R‐expressing CD8+ CTL clones specifically recognize human neuroblastoma tumor cells and are activated for tumor cell lysis and Tc1 cytokine production.ConclusionsThese data demonstrate the utility of CE7R for re‐directing the effector function of CTL to neuroblastoma and have provided the rationale to initiate a FDA‐authorized (BB‐IND#9149) pilot clinical trial to establish the feasibility and safety of adoptive transfer of autologous CE7R+CD8+ CTL clones to children with recurrent/refractory neuroblastoma. Copyright © 2004 John Wiley & Sons, Ltd.
In vivo gene electrotransfer into skeletal muscle: effects of plasmid DNA on the occurrence and extent of muscle damage
Authors: Durieux Anne‐Cécile , Bonnefoy Régis , Busso Thierry , Freyssenet Damien 
Published: March 2004

AbstractBackgroundUnderstanding the mechanisms underlying gene electrotransfer muscle damage can help to design more effective gene electrotransfer strategies for physiological and therapeutical applications. The present study investigates the factors involved in gene electrotransfer associated muscle damage.MethodsHistochemical analyses were used to determine the extent of transfection efficiency and muscle damage in the Tibialis anterior muscles of Sprague‐Dawley male rats after gene electrotransfer.ResultsFive days after gene electrotransfer, features of muscle degeneration and regeneration were consistently observed, thus limiting the extent of transfection efficiency. Signs of muscle degeneration/regeneration were no longer evident 21 days after gene electrotransfer except for the presence of central myonuclei. Neither the application of electrical pulses per se nor the extracellular presence of plasmid DNA per se contributed significantly to muscle damage (2.9 ± 1.0 and 2.1 ± 0.7% of the whole muscle cross‐sectional area, respectively). Gene electrotransfer of a plasmid DNA, which does not support gene expression, increased significantly muscle damage (8.7 ± 1.2%). When plasmid DNA expression was permitted (gene electrotransfer of pCMV‐β‐galactosidase), muscle damage was further increased to 19.7 ± 4.5%. Optimization of cumulated pulse duration and current intensity dramatically reduced gene electrotransfer associated muscle damage. Finally, mathematical modeling of gene electrotransfer associated muscle damage as a function of the number of electrons delivered to the tissue indicated that pulse length critically determined the extent of muscle damage.ConclusionOur data suggest that neither the extracellular presence of plasmid DNA per se nor the application of electric pulses per se contributes significantly to muscle damage. Gene electrotransfer associated muscle damage mainly arises from the intracellular presence and expression of plasmid DNA. Copyright © 2004 John Wiley & Sons, Ltd.
Recombinant bispecific antibodies for the targeting of adenoviruses to CEA‐expressing tumour cells: a comparative analysis of bacterially expressed single‐chain diabody and tandem scFv
Authors: Korn Tina , Nettelbeck Dirk M. , Völkel Tina , Müller Rolf , Kontermann Roland E. 
Published: March 2004

AbstractWe have generated two distinct recombinant bispecific antibody molecules for the retargeting of adenoviral vectors to CEA‐expressing tumour cells. These antibody molecules were produced by combining the antigen‐binding sites of a neutralising anti‐fibre knob scFv (S11) and an anti‐CEA antibody either in a single‐chain diabody format (scDb CEA‐S11) or a tandem scFv format (taFv CEA‐S11). In order to facilitate expression of taFv CEA‐S11 in bacteria we selected from a phage display library taFv molecules with an optimised linker that connects the two scFv fragments. ScDb CEA‐S11 and taFv CEA‐S11 were expressed and purified in soluble form from the bacterial periplasm with yields of approximately 100 µg per litre of bacterial culture. In vitro, both bispecific molecules mediated selective and enhanced transduction of CEA‐expressing tumour cells by recombinant adenoviruses. These assays did not reveal any differences in efficiency of adenoviral transduction by the two antibody formats. However, compared with taFv CEA‐S11, scDb CEA‐S11 exhibited a 2‐ to 3‐fold increased stability in human plasma at 37 °C. In summary, we could demonstrate that both formats are suitable for adenovirus targeting to tumour cells with similar biological activity in vitro. Copyright © 2004 John Wiley & Sons, Ltd.