bluuebunny/crossref_metadata_2025 huggingface dataset:
Transgene expression in hypertrophied and aged skeletal muscle in vivo by lentivirus delivery
Authors: Ouyang Jun , Alway Stephen E.
Published: March 2004

Background

Human immunodeficiency virus type 1 (HIV‐1)‐based lentiviral vectors can infect dividing and non‐dividing cells. The purpose of this study was to investigate the efficacy of lentiviral transfer of the green fluorescent protein (eGFP) gene into post‐mitotic quail skeletal muscle and into fibers undergoing hypertrophy and hyperplasia via addition of satellite cell nuclei.

Methods

A vesicular stomatitis virus G‐protein (pMFG)‐pseudotyped lentiviral vector encoding the eGFP gene coding sequence, flanked by two long terminal repeats (LTRs) (pHR‐CMV‐eGFP‐Wsin‐18) and an optional plasmid (pRSVrev), was generated in 293T cells by means of the three‐plasmid system. The resulting lentiviral vector, LtV/eGFP, was injected in vivo into the patagialis muscles of young (6 weeks of age) and senescent (100 weeks of age) Japanese quail. Polybrene (10 µg/muscle) was injected in the right patagialis muscles of some birds. A weight was attached to the left wing of birds immediately following LtV/eGFP injection for 7, 14 or 21 days to induce hypertrophy in the patagialis muscle via satellite cell activation. A time‐released bromodeoxyuridine (BrdU) pellet was implanted in some birds to identify satellite cells that had proliferated during stretch‐overload. Control and experimental muscles were examined 7, 14 or 21 days following injection and wing loading.

Results

Seven days post‐injection proved to be insufficient to visualize and quantify the eGFP signal. EGFP‐positive fibers were evident 14 and 21 days after injection of LtV/eGFP. As expected, wing weighting resulted in hypertrophy of the patagialis of senescent and young birds and an increase in collagen and other connective tissue in muscles of old birds. Nevertheless, this did not interfere with expression levels or intensity of the eGFP vector because the area of eGFP‐positive fibers normalized to total muscle area was similar in control and overloaded muscles, and in muscles that were injected with the lentivirus vector but not loaded. Polybrene improved eGFP expression by 41% as compared with muscles that received only the lentivirus.

Conclusions

These findings provide the first evidence that this lentivirus vector is an efficient tool for gene transfer and expression in mature (non‐growing) fibers of adult birds, sarcopenic fibers of senescent birds and hypertrophying skeletal muscle fibers of both young adult and old birds. This system could be useful for tissue engineering, or treating aging‐associated muscle‐wasting diseases such as sarcopenia, especially when exercise/overload are added to gene therapy approaches to combat muscle loss with aging. Copyright © 2004 John Wiley & Sons, Ltd.
Expression of HIV‐1 integrase in CEM cells inhibits HIV‐1 replication
Authors: van Griensven Johan , Zhan Xiaojing , Van Maele Bénédicte , Pluymers Wim , Michiels Martine , De Clercq Erik , Cherepanov Peter , Debyser Zeger
Published: March 2004

Background

HIV‐1 integrase (IN) is an interesting target for the gene therapy of AIDS. Although the in vivo functions are not well characterized, it is thought that IN has pleiotropic effects and plays a central role in the interplay between the virus and the host cell. Expression of IN in mammalian cells has proven difficult. We have previously established a 293T‐derived cell line that stably expresses high levels of HIV‐1 IN from a synthetic gene. We now have constructed CEM‐derived cell lines stably expressing the enzyme or its different domains and studied the impact of IN expression on HIV‐1 replication.

Methods

The CEM cell lines were selected following transduction with a retroviral vector encoding the full‐length IN, the N‐terminal domain, the catalytic core or the C‐terminal domain. Stable IN expression in CEM cell lines was verified by Western blotting. The impact of IN expression on HIV‐1 replication and HIV‐1 vector transduction was studied.

Results

A marked inhibitory effect on HIV‐1 replication was observed in CEM cells expressing IN. Expression of IN interfered with both particle production and integration. Expression of the N‐terminal domain alone was sufficient for the inhibiting of HIV‐1 replication.

Conclusions

Expression of IN in CEM cells inhibits HIV‐1 replication by a cumulative inhibitory effect on integration and particle production, in accord with the known pleiotropic interactions of IN. The inhibition of HIV‐1 replication in CEM cells expressing the N‐terminal domain of IN may lead to a novel approach for the gene therapy of AIDS. Copyright © 2004 John Wiley & Sons, Ltd.
Adenovirus vectors targeting αV integrin or heparan sulfate receptors display different distribution of transgene activity after intramuscular injection
Authors: Cirielli Corrado , Serino Francesco , Straino Stefania , Toietta Gabriele , Abeni Damiano , Ventoruzzo Giorgio , Orlando Giuseppe , Mazzanti Paola , Melillo Guido , Whickham Thomas J. , Kovesdi Imre , Biglioli Paolo , Gaetano Carlo , Capogrossi Maurizio C.
Published: March 2004

Background

Modification of the fiber proteins in replication‐deficient adenoviral (Ad) vectors through incorporation of specific receptor‐binding motifs may represent a strategy to enhance their tissue targeting capabilities.

Methods

In this study, we compared an unmodified Ad (GV10) with two mutated vectors obtained by insertion of specific target sequences that redirect binding, either toward αV integrin (RGD) or heparan sulfate (UTV) cellular receptors, for reporter gene expression spatial distribution in the rabbit skeletal muscle. In a first series of experiments, injection volume was kept constant and activity of a lacZ transgene was evaluated 48 h after injection of the Ad vectors at different doses. In separate experiments, the effects of different volumes of injection at a constant dose of Ad vector were monitored.

Results

All vectors evaluated showed a significant increase in the number of lacZ‐positive muscle segments, with increasing vector dose. However, in muscles treated with the UTV vector, fewer muscle fibers were β‐gal‐positive than in GV10 or RGD vector treated animals. In fact, total β‐gal activity increased in a dose‐dependent fashion in the GV10‐ and RGD‐treated muscles, but not in the UTV‐treated ones. Remarkably, in samples from UTV‐treated animals, a volume‐dependent enhancement of transgene expression was observed during experiments performed at the same dose and different injection volumes.

Conclusions

The results of the present study demonstrate that altering Ad affinity for cellular receptors modulates the level and distribution of transgene activity, conferring characteristics that may allow for treatment customization. Copyright © 2004 John Wiley & Sons, Ltd.
Suppression of tumor growth, invasion and angiogenesis of human gastric cancer by adenovirus‐mediated expression of NK4
Authors: Heideman Daniëlle A. M. , van Beusechem Victor W. , Bloemena Elisabeth , Snijders Peter J. F. , Craanen Mikael E. , Offerhaus G. Johan A. , Derksen Patrick W. B. , de Bruin Michiel , Witlox M. Adhiambo , Molenaar Bonnie , Meijer Chris J. L. M. , Gerritsen Winald R.
Published: March 2004

Background

To improve the prognosis of patients with gastric cancer it is important to develop novel treatment modalities targeting the malignant behavior of tumor cells. Concerning this, NK4, which acts as HGF‐antagonist and angiogenesis inhibitor, might be a potential therapeutic agent for gastric cancer. The HGF‐c‐MET pathway plays a pivotal role in gastric tumor growth, invasion, metastasis and angiogenesis. Therefore, the current study investigates whether adenoviral vector‐mediated NK4 gene therapy has therapeutic potential for gastric cancer.

Methods

Expression of HGF and c‐MET in normal and (pre‐)malignant gastric tissue was studied by immunohistochemistry. The effects of adenoviral vector‐mediated expression of NK4 on the biological behavior of gastric cancer cells were studied in vitro and in vivo.

Results

The majority of gastric cancers, i.e. 76%, express c‐MET and in all carcinomas HGF is expressed in either tumor or stromal cells. Normal gastric epithelial cells do not express either of these proteins. Transduction of gastric cancer cells with the replication‐deficient adenoviral vector AdCMV.NK4 resulted in efficient production and secretion of NK4. Consequently, proliferation, migration and invasion of gastric cancer cells were significantly inhibited. In addition, significantly reduced proliferation of vascular endothelial cells and efficient inhibition of angiogenesis were achieved. Finally, treatment of established human gastric tumor xenografts with AdCMV.NK4 resulted in significant tumor growth delay and significant reduction of intratumoral microvessel density.

Conclusions

The present study shows that adenoviral vector‐mediated expression of NK4 is a promising strategy to treat human gastric cancer by simultaneous interfering with primary tumor growth, metastasis and angiogenesis. Copyright © 2004 John Wiley & Sons, Ltd.
Polymer‐coated polyethylenimine/DNA complexes designed for triggered activation by intracellular reduction
Authors: Carlisle Robert C. , Etrych Tomas , Briggs Simon S. , Preece Jon A. , Ulbrich Karel , Seymour Leonard W.
Published: March 2004

Background

Site‐specific gene delivery requires vectors that combine stability in the delivery phase with substantial biological activity within target cells. The use of biological trigger mechanisms provides one promising means to achieve this, and here we report a transfection trigger mechanism based on intracellular reduction.

Methods

Plasmid DNA was condensed with thiolated polyethylenimine (PEI‐SH) and the resulting nanoparticles surface‐coated using thiol‐reactive poly[N‐(2‐hydroxypropyl)methacrylamide] (PHPMA) with 2‐pyridyldisulfanyl or maleimide groups, forming reducible disulphide‐linked or stable thioether‐linked coatings, respectively.

Results

Both sets of polymer‐coated complexes had similar size and were stable to a 250‐fold excess of the polyanion poly(aspartic acid) (PAA). Reduction with dithiothreitol (DTT) allowed complete release of DNA from disulphide‐linked coated complexes, whereas complexes with thioether‐linked coating remained stable. Disulphide‐linked complexes showed 40–100‐fold higher transfection activity than thioether‐linked ones, and activity was selectively further enhanced by boosting intracellular glutathione using glutathione monoethyl ester or decreased using buthionine sulfoximine. The chloroquine‐ and serum‐independent transfection activity of disulphide‐linked coated complexes suggests this system may provide a viable trigger mechanism to enable site‐specific transfection in complex biological settings.

Conclusions

Linkage of hydrophilic polymer coating to PEI/DNA complexes via reducible disulphide bonds offers a means of fulfilling the contradictory requirements for extracellular stability and intracellular activity. Copyright © 2004 John Wiley & Sons, Ltd.
In vitro and in vivo characterisation of endothelial cell selective adenoviral vectors
Authors: Nicklin Stuart A. , White Steve J. , Nicol Campbell G. , Von Seggern Dan J. , Baker Andrew H.
Published: March 2004

Background

Both viral and non‐viral gene transfer vectors transduce vascular endothelial cells (EC) with low efficiency compared with other cell types such as hepatocytes. Generation of EC‐selective vectors would enhance the clinical utility of gene therapy for diverse vascular‐targeted applications.

Methods

12mer peptides derived by in vitro phage display with EC binding specificity [MTPFPTSNEANL (MTP) and MSLTTPPAVARP (MSL)] were inserted at position T542 in the exposed HI loop of the adenovirus (Ad) serotype 5 fiber using overlapping oligonucleotides; in combination with a double point mutation (KO1) to ablate virus : cell binding via the coxsackie‐adenovirus receptor (CAR). The resulting modified viruses were tested in vitro and in vivo for their ability to direct endothelial‐specific gene transfer.

Results

Peptide insertion was not deleterious to fiber trimerisation or virion maturation. In vitro gene transfer studies using a panel of cell types demonstrated that both peptide‐targeted Ad vectors mediated efficient CAR‐independent gene transfer to vascular EC compared with non‐modified Ads. Neither peptide supported gene delivery to non‐EC. Upon systemic injection into mice and subsequent evaluation of transgene expression we failed to observe a reduction in hepatic Ad accumulation but observed a significant elevation in β‐galactosidase in blood vessels with the MSLTTPPAVARP‐targeted Ad vector.

Conclusions

We have genetically engineered two novel Ads that transduce human EC selectively in vitro, one of which leads to altered Ad biodistribution in vivo. The successful generation of genetically engineered tropism for EC has broad implications for cardiovascular gene therapy. Further modifications to the Ad capsid will be required to improve in vivo biodistribution profiles. Copyright © 2004 John Wiley & Sons, Ltd.
Gene transfection into fetal sheep airways in utero using guanidinium‐cholesterol cationic lipids
Authors: Luton Dominique , Oudrhiri Noufissa , de Lagausie Pascal , Aissaoui Abderrahim , Hauchecorne Michelle , Julia Sébastien , Oury Jean‐François , Aigrain Yves , Peuchmaur Michel , Vigneron Jean‐Pierre , Lehn Jean‐Marie , Lehn Pierre
Published: March 2004

Background

Over the last several years, we have developed a novel class of cationic lipids, cholesterol derivatives characterized by polar head groups with guanidinium functions. We have in particular shown that bis(guanidinium)‐tren‐cholesterol/dioleoylphosphatidylethanolamine (BGTC/DOPE) cationic liposomes can mediate efficient gene transfection into the mouse airways in vivo via direct intratracheal administration or intranasal instillation. As prenatal gene therapy may be necessary for the treatment of a variety of congenital lung diseases, we have explored in the present work the feasibility of BGTC‐mediated gene transfection into the respiratory tract of fetal sheep in utero.

Methods

Thus, BGTC/DOPE liposomes were complexed with plasmids expressing the Escherichia coli chloramphenicol acetyltransferase (CAT) reporter gene and the resulting lipoplexes were administered to fetal sheep at 70 days of gestation via surgical replacement of the airway fluid by the transfection mixture followed by tracheal occlusion. The fetal lungs and tracheas were harvested at 72 h and examined for CAT expression and evidence of toxicity.

Results

CAT expression was detected in both lung and trachea homogenates, no CAT expression being observed in control fetuses receiving naked plasmid DNA. Immunohistochemical analysis showed that airway epithelial cells and some mesenchymal cells were transfected. Pulmonary histopathology of varied severity was however observed under our transfection conditions and manifested as focal epithelial and mesenchymal lesions.

Conclusions

These results show that BGTC/DOPE liposomes can mediate gene transfection into the fetal sheep airway epithelium. They also invite the development of optimized BGTC‐based formulations and administration conditions with a view to future prenatal gene transfer experiments involving therapeutic genes. Copyright © 2004 John Wiley & Sons, Ltd.
Synthesis and receptor binding of IgG1 peptides derived from the IgG Fc region
Authors: Uray Katalin , Medgyesi Dávid , Hilbert Ágnes , Sármay Gabriella , Gergely János , Hudecz Ferenc
Published: March 2004

The IgG binding Fcγ receptors (FcγRs) play a key role in defence against pathogens by linking humoral and cell‐mediated immune responses. Impaired expression and/or function of FcγR may result in the development of pathological autoimmunity. Considering the functions of FcγRs, they are potential target molecules for drug design to aim at developing novel anti‐inflammatory and immunomodulatory therapies. Previous data mostly obtained by X‐ray analysis of ligand–receptor complexes indicate the profound role of the CH2 domain in binding to various FcγRs. Our aim was to localize linear segments, which are able to bind and also to modulate the function of the low affinity FcγRs, like FcγRIIb and FcγRIIIa. To this end a set of overlapping octapeptides was prepared corresponding to the 231–298 sequence of IgG1 CH2 domain and tested for binding to human recombinant soluble FcγRIIb. Based on these results, a second group of peptides was synthesized and their binding properties to recombinant soluble FcγRIIb, as well as to FcγRs expressed on the cell surface, was investigated. Here we report that peptide representing the Arg255–Ser267 sequence of IgG1 is implicated in the binding to FcγRIIb. In addition we found that peptides corresponding to the Arg255–Ser267, Lys288–Ser298 or Pro230–Val240 when presented in a multimeric form conjugated to branched chain polypeptide in uniformly oriented copies induced the release of TNFα, a pro‐inflammatory cytokine from MonoMac monocyte cell line. These findings indicate that these conjugated peptides are able to cluster the activating FcγRs, and mediate FcγR dependent function. Peptide Arg255–Ser267 can also be considered as a lead for further functional studies. Copyright © 2004 John Wiley & Sons, Ltd.
The substrate recognition mechanisms in chaperonins
Authors: Gómez‐Puertas Paulino , Martín‐Benito Jaime , Carrascosa José L. , Willison Keith R. , Valpuesta José M.
Published: March 2004

Chaperonins are a family of proteins devoted to assisting the folding of other proteins. They are large oligomers assembled into ring structures that enclose a cavity in which folding takes place. For this process to occur, the chaperonin must first recognize and interact with the unfolded polypeptide, then undergo a conformational change upon nucleotide binding that results in the closure of the cavity which in turn mediates the folding reaction inside the cavity. Although this general mechanism seems to apply to every chaperonin studied so far, there exist two different modes of interaction between the chaperonin and the substrate. The first occurs mainly through the interaction between the exposed hydrophobic residues of the unfolded polypeptides and those of the chaperonin substrate binding site, as elucidated for the chaperonin GroEL from E. coli. The second type of mechanism has been described so far only for the cytosolic chaperonin CCT (Chaperonin Containing TCP‐1) and here the interaction seems to be of a more specific nature, involving charged and polar residues in both the chaperonin and the substrate, which interacts with CCT in a structured, quasi‐native conformation. Copyright © 2004 John Wiley & Sons, Ltd.
Kinetic and thermodynamic characterization of HIV‐1 protease inhibitors
Authors: Shuman Cynthia F. , Hämäläinen Markku D. , Danielson U. Helena
Published: March 2004

Interaction kinetic and thermodynamic analyses provide information beyond that obtained in general inhibition studies, and may contribute to the design of improved inhibitors and increased understanding of molecular interactions. Thus, a biosensor‐based method was used to characterize the interactions between HIV‐1 protease and seven inhibitors, revealing distinguishing kinetic and thermodynamic characteristics for the inhibitors. Lopinavir had fast association and the highest affinity of the tested compounds, and the interaction kinetics were less temperature‐dependent as compared with the other inhibitors. Amprenavir, indinavir and ritonavir showed non‐linear temperature dependencies of the kinetics. The free energy, enthalpy and entropy (ΔG, ΔH, ΔS) were determined, and the energetics of complex association (ΔGon, ΔHon, ΔSon) and dissociation (ΔGoff, ΔHoff, ΔSoff) were resolved. In general, the energetics for the studied inhibitors was in the same range, with the negative free energy change (ΔG < 0) due primarily to increased entropy (ΔS > 0). Thus, the driving force of the interaction was increased degrees of freedom in the system (entropy) rather than the formation of bonds between the enzyme and inhibitor (enthalpy). Although the ΔGon and ΔGoff were in the same range for all inhibitors, the enthalpy and entropy terms contributed differently to association and dissociation, distinguishing these phases energetically. Dissociation was accompanied by positive enthalpy (ΔHoff > 0) and negative entropy (ΔSoff < 0) changes, whereas association for all inhibitors except lopinavir had positive entropy changes (ΔSon > 0), demonstrating unique energetic characteristics for lopinavir. This study indicates that this type of data will be useful for the characterization of target–ligand interactions and the development of new inhibitors of HIV‐1 protease. Copyright © 2004 John Wiley & Sons, Ltd.
The role of flexibility and hydration on the sequence‐specific DNA recognition by the Tn916 integrase protein: a molecular dynamics analysis
Authors: Gorfe Alemayehu A. , Caflisch Amedeo , Jelesarov Ilian
Published: March 2004

The N‐terminal domain of the Tn916 integrase protein (INT‐DBD) is responsible for DNA binding in the process of strand cleavage and joining reactions required for transposition of the Tn916 conjugative transposon. Site‐specific association is facilitated by numerous protein–DNA contacts from the face of a three‐stranded β‐sheet inserted into the major groove. The protein undergoes a subtle conformational transition and is slightly unfolded in the protein–DNA complex. The conformation of many charged residues is poorly defined by NMR data but mutational studies have indicated that removal of polar side chains decreases binding affinity, while non‐polar contacts are malleable. Based on analysis of the binding enthalpy and binding heat capacity, we have reasoned that dehydration of the protein–DNA interface is incomplete. This study presents results from a molecular dynamics investigation of the INT–DBD–DNA complex aimed at a more detailed understanding of the role of conformational dynamics and hydration in site‐specific binding. Comparison of simulations (total of 13 ns) of the free protein and of the bound protein conformation (in isolation or DNA‐bound) reveals intrinsic flexibility in certain parts of the molecule. Conformational adaptation linked to partial unfolding appears to be induced by protein–DNA contacts. The protein–DNA hydrogen‐bonding network is highly dynamic. The simulation identifies protein–DNA interactions that are poorly resolved or only surmised from the NMR ensemble. Single water molecules and water clusters dynamically optimize the complementarity of polar interactions at the ‘wet’ protein–DNA interface. The simulation results are useful to establish a qualitative link between experimental data on individual residue's contribution to binding affinity and thermodynamic properties of INT–DBD alone and in complex with DNA. Copyright © 2004 John Wiley & Sons, Ltd.
Identification of differences in the specificity‐determining residues of antibodies that recognize antigens of different size: implications for the rational design of antibody repertoires
Authors: Almagro Juan C.
Published: March 2004

Studies of antibodies of known three‐dimensional structure have revealed that insertion and deletion of amino acids at the hypervariable loops change the canonical structures, thus generating differences in the antigen‐binding site topography. Such differences determine the size of the antigen with which the antibody interacts. Here, 59 unique antibodies determined at a resolution of 3.0 Å or below, including 19 in complex with proteins, 18 with peptides and 22 with haptens, were analyzed to identify and characterize differences in the residues that are directly involved in the interaction with antigen, so‐called specificity‐determining residues (SDRs). It was found that antibodies use a similar number of SDRs to recognize proteins and peptides but contact haptens with five SDRs less. By using a score of SDR usage, differences in the location of the SDRs, depending on the type of antigen recognized, were then identified with precision. An analysis of the surface generated by the SDRs usage indicates that the differences found correlate well with the size of the antigen. Anti‐protein antibodies have the largest SDR surface, with SDRs of high usage located in the edge of the surface. The SDR surface of anti‐hapten antibodies is the smallest, with hot spots of contacts in the interior of the binding surface and buried in the VL:VH interface. The SDR surface of anti‐peptide antibodies has a size in between anti‐protein and anti‐hapten antibodies, with the SDRs of high usage located in the interior of the antigen‐binding site but do not buried as in anti‐hapten antibodies. These findings led to a fine‐tuning of the model correlating differences in the antigen‐binding site topography with its preference to recognize antigens of different size. Therefore, it is discussed how this knowledge should help to design antibody repertoires biased toward the recognition of antigens of predefined size. Copyright © 2004 John Wiley & Sons, Ltd.
Comparative study of the phototoxicity of two chrolin type photosensitizers, ATX‐S10(Na) and verteporfin, on vascular endothelial and retinal pigment epithelial cells
Authors: Huang Yufang , Obana Akira , Gohto Yuko , Nakajima Susumu
Published: March 2004

Background and Objectives

To compare the phototoxicity in photodynamic therapy (PDT) of ATX‐S10(Na) and Verteporfin on human microvascular endothelial cells (HMVEC), vascular endothelial cells of monkey choroid and retina (CRVEC), and human retinal pigment epithelial cells (HRPE).

Study Design/Materials and Methods

PDT was performed in two different ways. In short dye‐exposure PDT, HMVEC and CRVEC were exposed to each photosensitizer for 5 minutes followed by laser irradiation of 670 nm wavelength for ATX‐S10(Na) or 689 nm for Verteporfin without washing out the photosensitizer in the medium. In long dye‐exposure PDT, the cells were exposed to photosensitizers for times ranging from 5 minutes to 2 hours, washed out the photosensitizers, followed by laser irradiation in a fresh medium. PDT was performed on HRPE with PDT doses that resulted in damaging 90% of the HMVEC (ED90). Phototoxicity was determined by MTS Assay 1 day after PDT.

Results

The degree of phototoxicity depended on the dye concentration, laser dose, and dye exposure time. In short dye‐exposure PDT on HMVEC with a laser dose of 50 J/cm2, the ED90 was 6.3 μg/ml of ATX‐S10(Na) and 0.04 μg/ml of Verteporfin, while in long dye‐exposure PDT the ED90 was 50.0 μg/ml of ATX‐S10(Na) and 0.04 μg/ml of Verteporfin when the medium was supplemented with 5% fetal calf serum. The phototoxic rate on HMVEC was higher when the medium contained 5% as contrasted with 10% of serum. In short dye‐exposure PDT, the ED90 of CRVEC was 100 μg/ml of ATX‐S10(Na) and an irradiance of 100 J/cm2 , and 0.08 μg/ml of Verteporfin and an irradiance of 100 J/cm2 when the medium was supplemented with 10% serum. With some doses of short dye‐exposure PDT, the ATX‐S10(Na) achieved higher phototoxic rates on HMVEC and CRVEC than on the HRPE. However, long dye‐exposure PDT with ATX‐S10(Na) and short and long dye‐exposure PDT with Vereteporfin failed to obtain higher phototoxic rates on HMVEC and CRVEC than on HRPE.

Conclusions

Verteporfin had a higher phototoxicity than ATX‐S10(Na) on HMVEC and CRVEC. The CRVEC resisted more than HMVEC following PDT with both photosensitizers. In short dye‐exposure PDT, ATX‐S10(Na) had a more selective phototoxicity on HMVEC and CRVEC than on HRPE. Lasers Surg. Med. 34:216–226, 2004. © 2004 Wiley‐Liss, Inc.
Flashlamp pulsed dye laser (FPDL) did not cure papulopustular rosacea
Authors: Berg Mats , Edström Desiree Wiegleb
Published: March 2004

Background and Objectives

Pharmacological treatment has a fairly good effect on the papulopustular lesions in rosacea, but not as good an effect on the erythema and telangiectases. The aim was to treat rosacea patients with both erythematotelangiectatic and papulopustular lesions with flashlamp pulsed dye laser (FPDL) until telangiectases/erythema disappeared, and to evaluate whether the treatment might also be effective on papulopustular lesions.

Study Design/Materials and Methods

Ten patients were treated on one side of the face with FPDL. The final examination was blinded and performed on the average 10 months after the last treatment.

Results

Two of the patients had more lesions after treatment, three were unchanged, three had only slightly less, and two had markedly less papulopustular lesions.

Conclusion

Our conclusion from this small sample of patients is that FPDL probably has limited value on papulopustular lesions in rosacea. This indicates that the origin of rosacea may not be only vascular. Lasers Surg. Med. 34:266–268, 2004. © 2004 Wiley‐Liss, Inc.
Effect of low power 655 nm diode laser irradiation on the neuromuscular junctions of the mouse diaphragm
Authors: Nicolau Renata Amadei , Martinez Manel Santafé , Rigau Josepa , Tomàs Josep
Published: March 2004

Background and Objectives

Low level laser therapy (LLLT) in specific wavelengths and fluence maintains the electrophysiological activity of injured peripheral nerve in rats, preventing scar formation (at injury site) as well as degenerative changes in the corresponding motor neurons of the spinal cord, thus accelerating regeneration of the injured nerve. We studied the effect of LLLT on the neurotransmitter release in neuromuscular junctions of the mouse diaphragm.

Study Design/Materials and Methods

Thirty‐nine diaphragm muscles were studied. LLLT with GaAlAs 655 nm (1–12 J/cm2) was used. Neurotransmitter release was studied by conventional intracellular recording techniques on curarised or high magnesium media. Quantal content, amplitude, latency and rise time were analysed for end‐plate potentials (EPPs). Frequency and amplitude were evaluated for the miniature end‐plate potentials (MEPPs). Short‐term plasticity of the neurotransmitter release (fast facilitation) was also evaluated by paired pulse stimulation.

Results and Conclusions

This study showed that LLLT (655 nm) in these doses has no detectable physiological effect on the motor end‐plate neurotransmitter release in mice. Lasers Surg. Med. 34:277–284, 2004. © 2004 Wiley‐Liss, Inc.
Influence of pulse duration and pulse number in selective RPE laser treatment
Authors: Framme Carsten , Schuele Georg , Roider Johann , Birngruber Reginald , Brinkmann Ralf
Published: March 2004

Background and Objectives

The therapeutic effect of laser treatment for macular diseases is related to the damage to the retinal pigment epithelium (RPE) and the subsequent restoration of the defect due to RPE proliferation. In contrast to conventional laser treatment, it is possible to damage the RPE selectively and to spare the photoreceptors by using repetitive microsecond laser pulses. It was the aim of the study to investigate the influence of pulse duration and number of pulses on angiographically and ophthalmoscopically visible retinal damage thresholds in order to optimize treatment modalities.

Study Design/Materials and Methods

In total, 625 laser lesions with various parameters were applied to the retina in 11 eyes of 6 Chinchilla breed rabbits using an experimental laser system (Nd:YLF at 527 nm). Pulse duration (1.7 microseconds and 200 nanoseconds) and number of pulses (100, 10, and 1 pulses) were varied at a constant repetition rate of 100 Hz. Damage thresholds were determined in terms of ophthalmoscopic and fluorescein angiographic visibility, and the therapeutic window (TW; angiographic ED50 vs. ophthalmoscopic ED50) as well as the safety range (SR; angiographic ED84 vs. ophthalmoscopic ED16) between both thresholds were calculated. Selected laser lesions were evaluated by histology.

Results

Generally, the ED50 radiant exposure for angiographic visibility decreases for shorter laser pulses and with an increase in the number of pulses. The TW for both pulse durations (1.7 microseconds and 200 nanoseconds) was wider with 100 pulses than with single pulses. The widest TW was found for 100 pulses at 200 nanoseconds pulse duration (5.9‐fold above the angiographic threshold), and the smallest TW with a factor of 1.6 was found for 1.7 microseconds single pulses. In terms of SR, only irradiation with 100 pulses at 200 nanoseconds pulse duration was associated with a ratio >2. Independently of pulse duration, histological examination of laser sites 1 hour after irradiation revealed widely intact photoreceptors, while the underlying RPE was damaged.

Conclusions

Pulse duration and number of pulses have a significant influence on RPE damage thresholds and consecutively on TW and SR. Because fundus pigmentation in humans may vary intra‐ and interindividually by a factor of 2, a large TW and ideally also a large SR should be ensured in a clinical treatment context. In rabbits, the safety range with 200 nanoseconds pulses is higher than with the pulse duration of 1.7 microseconds currently in clinical use. These findings suggest the need for clinical pilot studies to prove whether these results can be transposed to the situation in humans. Lasers Surg. Med. 34:206–215, 2004. © 2004 Wiley‐Liss, Inc.
Radical Copolymerization of α‐Trifluoromethylacrylic Acid with Vinylidene Fluoride and Vinylidene Fluoride/Hexafluoropropene
Authors: Souzy Renaud , Ameduri Bruno , Boutevin Bernard
Published: March 2004

Summary: The radical copolymerization of α‐trifluoromethylacrylic acid (TFMAA) with vinylidene fluoride (VDF), initiated by tert‐butyl 2,2‐dimethyl peroxypropanoate (or tert‐butyl peroxypivalate) is presented. The kinetics of copolymerization were investigated from a series of eight reactions for which the initial [VDF]0/[TFMAA]0 molar ratios ranged between 15.0/85.0 and 89.4/10.6. The compositions of the copolymers, i.e. the molar ratios of VDF and TFMAA monomeric units, were determined mainly by 19F and 1H NMR spectroscopy. According to the Tidwell and Mortimer method, the reactivity ratios, ri, were assessed to be: rVDF = 0.33 ± 0.09 and rTFMAA = 0 at 55 °C, leading to copolymers of mainly alternating structure. Then, the radical terpolymerization of TFMAA with VDF and hexafluoropropene (HFP), initiated by 2,5‐bis(tert‐butylperoxy)‐2,5‐dimethylhexane is described and the thermal properties of the materials produced are discussed.

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The Structure of the Free Volume in Poly(styrene‐co‐acrylonitrile) from Positron Lifetime and Pressure Volume Temperature (PVT) Experiments
Authors: Dlubek Günter , Pionteck Jürgen , Kilburn Duncan
Published: March 2004

Summary: The structure of the free volume and its temperature dependence between 25 and 190 °C of copolymers of styrene with acrylonitrile, SAN (0 to 50 mol‐% AN), is studied by pressure volume temperature (PVT) experiments and positron annihilation lifetime spectroscopy (PALS). In this first part of the work, PVT data are reported which were analysed with the Simha‐Somcynsky equation of state (S‐S eos) to estimate the volume fraction of holes, h, which constitute the excess free volume. The temperature and pressure dependence of the specific volume V, the specific occupied and free volume, Vocc = (1 − h)V and Vf = hV, and the corresponding isobaric expansivities and isothermal compressibilities for both the rubbery and glassy state, are estimated. We obtained the unexpected results that (i) the occupied volume changes its coefficient of thermal expansion at Tg from αocc,g ≈ 0.5αg ≈ 1 × 10−4 K−1 below Tg to almost zero above Tg and (ii) the isothermal compressibility of the occupied volume at zero pressure is rather high, κocc ≈ 2 × 10−4 MPa−1, and decreases only slightly at Tg. The variation of total, occupied, and free volume parameters with the composition of the SAN copolymers is discussed.

Specific volume V of SAN50 as a function of temperature T and as selection of isobars (in MPa).

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Specific volume V of SAN50 as a function of temperature T and as selection of isobars (in MPa).
Salience and choice: Neural correlates of shopping decisions
Authors: Ambler Tim , Braeutigam Sven , Stins John , Rose Steven , Swithenby Stephen
Published: March 2004

Noninvasive brain imaging was used to observe 18 subjects, each making 90 choices of three brands on a virtual (video) supermarket visit. Package height provided a control for the main experiment. Brain activations in brand choice differed from those for height discrimination, and choice times were faster when one brand was more familiar. Brand choice appeared to involve silent vocalization. Decision processes took approximately 1 s and can be seen as two halves. The first period seems to involve problem recognition and here male brain patterns differed from female. The second half concerned the choice itself. No male/female differences were observed but a different pattern was evoked where one brand was familiar and the other two were not. The right parietal cortex was strongly activated in this case. This research pioneers new techniques using relatively few subjects and against a limited theoretical background. As such it must be classified as exploratory. © 2004 Wiley Periodicals, Inc.
The interplay of social influence and nature of fulfillment: Effects on consumer attitudes
Authors: Bailey Ainsworth Anthony
Published: March 2004

Sales promotional activities account for a significant portion of the integrated marketing communications budget of most companies because brand managers realize the effectiveness of these activities in meeting certain marketing communication objectives. However, there are times when promotional plans backfire, and promotions go unfulfilled. Much of this is reported in the media, and these reports are likely to trigger discussions about the companies involved in the nonfulfillment. Although much research has focused on the impact of sales promotional activities on consumers' responses and attitudes, not much has focused on how nonfulfillment of promotional promises and social influence might operate to color consumers' perceptions of a company. This article reports on an experimental study that was conducted to investigate this issue. Results indicate significant effects of the nature of fulfillment on corporate credibility, brand attitude, and patronage intentions; significant social influence effects on brand attitude, patronage, and switching intentions; and an interaction effect of social influence and fulfillment on switching intentions. The implications for brand managers and marketing communications managers are discussed, and areas for future research are proposed. © 2004 Wiley Periodicals, Inc.
Advancing means–end chains by incorporating Heider's balance theory and Fournier's consumer–brand relationship typology
Authors: Woodside Arch G.
Published: March 2004

Means–end chain theory proposes that knowledge held in consumer's memory is organized in a hierarchy with concrete thoughts linked to more abstract thoughts in a sequence progressing from means (i.e., product features), to psychological and social consequences, and finally to ends (i.e., fulfillment of personal values). This article proposes several advances in the theory. First, specific buying and consumption situations serve as frames of reference when consumers are thinking about products and alternative features of products and brands. Second, states of psychological imbalance may occur in consumers' minds among linkages retrieved automatically for features–consequences and consequences–values; thus, Heider's balance theory informs means–end chain theory and research. The theoretical and practical usefulness of means–end research increases from asking consumers to name an acceptable alternative to the product and brand used in a recent consumption situation, as well as an unacceptable option, and to describe the features–consequences–values of these options; consequently, Fournier's alternative relationships of consumer–brands (e.g., casual friendships, marriages, enmities) become relevant for means–end chain theory. To examine the propositions empirically, the article describes psychological schemas for four means–end chains that link two consumers' recent lived consumption situations to personal values. © 2004 Wiley Periodicals, Inc.
A nonverbal test of naturalistic memory for alcohol commercials
Authors: Stacy Alan W. , Pearce Steve G. , Zogg Jennifer B. , Unger Jennifer , Dent Clyde W.
Published: March 2004

This study investigated a nonverbal test of memory for naturally occurring events: alcohol commercials. Such tests, supported by dual‐code and transfer‐appropriate processing perspectives from basic research, are useful for research on consumer behavior and public health. The participants were 750 adolescents who completed a nonverbal test of memory, tailored to detect prominent visual features of remembered alcohol commercials. The results showed (a) that independent judges reliably coded primary features of remembered advertisements along most dimensions, and (b) the test met important criteria for convergent and discriminant validity in comparisons with other measures. Applications were proposed for research on advertising effects, health behavior, and media copy testing. © 2004 Wiley Periodicals, Inc.
Psychogenic palatal tremor
Authors: Williams David R.
Published: March 2004

Recent criteria for the classification of palatal tremor use clinical, imaging, and electrophysiological features to differentiate essential and symptomatic forms. A case of probable psychogenic palatal tremor (PPT) is described within the context of these criteria, which lack clear guidelines for diagnosing PPT. The heterogenous nature of essential palatal tremor and its relationship with PPT, voluntary palatal movements, and tics is discussed. © 2003 Movement Disorder Society
Gliomatosis cerebri may present as an atypical parkinsonian syndrome
Authors: Molho Eric S.
Published: March 2004

An 85‐year‐old man presented with 3 years of a progressive akinetic rigid syndrome with ataxia, falls, levodopa unresponsiveness, and autonomic dysfunction. Early in the course of illness, cranial magnetic resonance imaging (MRI) was thought to show pontine enlargement but later was reinterpreted by experts as normal. Two subsequent cranial MRIs were believed to show only mild atrophy. An initial clinical diagnosis of multiple system atrophy was made. The patient died 4 years after the onset of symptoms. Pathological examination revealed diffuse infiltration of multiple brain regions with cells of astrocytic and microglial origin consistent with a diagnosis of gliomatosis cerebri. © 2003 Movement Disorder Society
Identification of psychogenic, dystonic, and other organic tremors by a coherence entrainment test
Authors: McAuley John , Rothwell John
Published: March 2004

The differentiation of psychogenic from organic tremors, particularly those of a dystonic nature, can be difficult on clinical grounds. Entrainment of tremulous movements of different body parts into a single rhythm has been used clinically as a means of distinguishing these tremor forms, based on the inability of a patient with hysterical tremor to generate voluntary tapping oscillations independent of their ongoing tremor oscillation. The coherence entrainment test is a quantified electrophysiological entrainment test performed on accelerometer or surface EMG tremor signals. This test was carried out on 25 patients referred with suspected psychogenic tremor or dystonic tremor and on 10 normal subjects attempting to tap two independent voluntary oscillations. Using established and new clinical diagnostic criteria, patients were assigned the following final clinical diagnoses: 6 cases of clinically definite dystonic tremor, 5 cases of probable dystonic tremor, 2 cases of classic essential tremor, 5 cases of clinically definite psychogenic tremor, 3 cases of probable psychogenic tremor and 4 uncertain cases. On comparing these clinical diagnoses with those reached by a coherence entrainment test subsequently carried out on each patient, there was 100% concordance in both clinically definite and clinically probable patients. In uncertain cases, when later clinical information came to light, this also corroborated with the coherence entrainment diagnosis. No normal subjects were able to “mimic” organic tremor. The coherence entrainment test appears to be a sensitive and specific means of distinguishing psychogenic tremor from dystonic and other organic tremors. © 2003 Movement Disorder Society
Initial boundary value problem for a system of generalized IMBq equations
Authors: Chen Guowang , Zhang Hongwei
Published: March 2004

The existence and uniqueness of the global generalized solution and the global classical solution to the initial boundary value problem for a system of generalized IMBq equations

are proved. This paper also arrives at some sufficient conditions of blow up of the solution in finite time. Copyright © 2004 John Wiley & Sons, Ltd.
Wave front sets of the Riemann function of elastic interface problems
Authors: Shimizu Senjo
Published: March 2004

We obtain an inner and an outer estimates of wave front sets and analytic wave front sets of the Riemann function of elastic interface problems by using the localization method due to Wakabayashi. In our problem the outer estimate of wave front sets and analytic wave front sets of the Riemann function coincides with the inner estimate of those. The strong point of our results is to catch the lateral wave as well as the incident, the reflected, and the refracted waves. Copyright © 2004 John Wiley & Sons, Ltd.
Robust exponential attractors for Cahn‐Hilliard type equations with singular potentials
Authors: Miranville Alain , Zelik Sergey
Published: March 2004

Our aim in this article is to study the long time behaviour of a family of singularly perturbed Cahn‐Hilliard equations with singular (and, in particular, logarithmic) potentials. In particular, we are able to construct a continuous family of exponential attractors (as the perturbation parameter goes to 0). Furthermore, using these exponential attractors, we are able to prove the existence of the finite dimensional global attractor which attracts the bounded sets of initial data for all the possible values of the spatial average of the order parameter, hence improving previous results which required strong restrictions on the size of the spatial domain and to work on spaces on which the average of the order parameter is prescribed. Finally, we are able, in one and two space dimensions, to separate the solutions from the singular values of the potential, which allows us to reduce the problem to one with a regular potential. Unfortunately, for the unperturbed problem in three space dimensions, we need additional assumptions on the potential, which prevents us from proving such a result for logarithmic potentials. Copyright © 2004 John Wiley & Sons, Ltd.
Modelling traffic flow with a time‐dependent fundamental diagram
Authors: Li Tong
Published: March 2004

We model traffic flow with a time‐dependent fundamental diagram. A time‐dependent fundamental diagram arises naturally from various factors such as weather conditions, traffic jam or modern traffic congestion managements, etc. The model is derived from a car‐following model which takes into account the situation changes over the time elapsed time. It is a system of non‐concave hyperbolic conservation laws with time‐dependent flux and the sources.

The global existence and uniqueness of the solution to the Cauchy problem is established under the condition that the variation in time of the fundamental diagram is bounded. The zero relaxation limit of the solutions is found to be the unique entropy solution of the equilibrium equation. Copyright © 2004 John Wiley & Sons, Ltd.
Approximation by Maxwell–Herglotz‐fields
Authors: Weck Norbert
Published: March 2004

By a general argument, it is shown that Maxwell–Herglotz‐fields are dense (with respect to the C∞(Ω)‐topology) in the space of all solutions to Maxwell's equations in Ω. This is used to provide corresponding approximation results in global spaces (e.g. in L2‐Sobolev‐spaces Hm(Ω)) and for boundary data. Proofs are given within the framework of generalized Maxwell's equations using differential forms. Copyright © 2004 John Wiley & Sons, Ltd.
Stupidity and the software bullet
Authors: Held Gilbert
Published: March 2004

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