bluuebunny/crossref_metadata_2025 huggingface dataset:
Immunosuppression in Sarcocystis muris‐infected mice: Evidence for suppression of antibody and cell‐mediated responses to a heterologous antigen
Authors: Gill HS , Charleston WAG , Moriarty KM
Published: July 2007

Mice infected with Sarcocystis maris showed a significant reduction in plaque‐forming cells (PFC) and delayed‐type hypersensitivity (DHS) responses to an unrelated protein antigen, bovine γ‐globulin, when compared with uninfected controls. This immunosuppression was observed only when infection preceded immunization or when mice were immunized concurrently with infection, suggesting that suppression induced by murine sarcocystosis affected the induction and/or the differentiation of antigen‐sensitive immunocytes. The immunosuppression lasted for 5 weeks, the period of this study, and affected cell‐mediated responses more than antibody responses. The secondary PFC and DHS responses of mice immunized 14 days after infection and re‐immunized 21 days later were also significantly lower than those of uninfected controls, whereas the secondary PFC and DHS responses of mice primed before infection were unimpaired. This indicated that S. muris infection affects only the induction but not the expression of immune memory.
Production of a polyspecific human monoclonal antibody reacting with an epidermal antigen
Authors: Hohmann Arthur W , Coleman Mark , Comacchio Raffaela M , Skinner John M , Bradley John
Published: July 2007

A clone of cells secreting an antibody to an epidermal antigen was generated from a patient with a blistering skin lesion. Although produced by fusion of human lymphocytes to a HAT‐sensitive myeloma, this clone of cells did not have characteristics of a hybridoma. A true hybridoma was produced by fusion of this clone to a HATr/ouabainr myeloma line. The IgM antibody secreted by this clone reacted with the intercellular region of the epidermis of normal human skin in a manner similar to pemphigus autoantibodies. In addition, in normal human kidney the antibody bound to glomeruli and tubules. It also reacted with an antigen present in the cytoplasm of a wide variety of cell lines including epithelial, lymphoid and myeloid types. No reaction was found with the surface of any of the cell lines, nor with DNA or phospholipid antigens.

This monoclonal antibody may define an autoantibody specificity which mediates some autoimmune skin lesions. Its polyspecificity is reminiscent of some other human hybridoma autoantibodies, and its reaction with components of the kidney suggests an alternative pathology for renal disease in such patients.
Immunomodulation of human fetal cells by the fungal metabolite gliotoxin
Authors: Tuch Bernard E , Lissing Judith R , Suranyi Michael G
Published: July 2007

Gliotoxin (GT) is a fungal metabolite that reduces the ability of murine macrophages to react immunologically in vitro. It is also capable of modulating the immunogenicity of murine bone marrow cells, so that the onset of graft‐versus‐host disease in fully allogeneic bone marrow chimeras is delayed. The present study examines the effect of GT on human fetal cells, both in terms of reduction of immunogenicity and toxicity. GT (10 μg/ml) significantly decreased the responsiveness in mixed lymphocyte cultures of cells derived from human fetal pancreas, spleen, liver and bone marrow. This concentration of GT was, however, mildly toxic to explants of the pancreas, with a significant reduction in insulin secretion from this tissue during the first day of its organ culture, but not thereafter. GT‐treated pancreatic explants were lighter and contained less insulin than the untreated controls 3 months after the tissue had been implanted beneath the renal capsule of nude mice. This difference was not apparent 3 weeks after transplantation into these animals. It is hypothesized that the immuno‐modulating effect of GT (at a concentration less than 10 μg/ml) may be of benefit in treating allografted human fetal pancreas before it is transplanted, as it has for murine adult bone marrow cells.
Specific in vitro anti‐tumour activity of methotrexate‐monoclonal antibody conjugates prepared using human serum albumin as an intermediary
Authors: Pietersz Geoffrey A , Cunningham Zita , McKenzie Ian FC
Published: July 2007

Methotrexate (MTX) is a folic acid antagonist widely used in the treatment of cancer but, like other such agents, has non‐specific toxic side effects. With the aim of reducing these toxic effects, MTX was coupled to monoclonal antibodies (MoAb) in one of two ways; either (a) directly using an active ester derivative or (b) via human serum albumin (HSA), to act as an intermediary and so increase the amount of MTX bound. The MTX coupled directly to anti‐Ly‐2.1 antibody had approximately 10 molecules of MTX per antibody molecule, whereas the HSA coupled material had 24 molecules of MTX per antibody molecule. After coupling MTX directly to antibody there was a loss of potency of the MTX, and MTX‐MoAb conjugates were 30‐fold less potent than free MTX, although the antibody‐coupled material was more specific than free MTX and bound only to the antibody‐reactive target cells. By contrast, the MTX‐HSA‐MoAb conjugates were 3·5 times less potent than free MTX and were 8·5 times more potent than MTX‐MoAb conjugates. Thus, by increasing the amount of drug bound to antibody, more toxic conjugates were made – an important principle for the use of such conjugates for the treatment of cancer in man.
Lymphopenic effects on mice of a component of ammonia caramel, 2‐acetyl‐4(5)‐tetrahydroxybutylimidazole (THI)
Authors: Iscaro Angelina , Mackay Ian R , O'Brien Catherine
Published: July 2007

A derivative of ammonia caramel colour (AC) is known to induce a selective lymphopenia in rats. Accordingly, the haematological effects were studied in mice of oral administration in drinking water of 2‐acetyl‐4(5)‐tetrahydroxybutylimidazole (THI), the component of AC responsible for lymphopenia. Initially five groups of BALB/c mice (five mice per group) were given doses of THI ranging from 0 to 200 parts/106 and bled weekly. Doses of THI from 5 to 100 parts/106 had no effect on circulating leucocytes over 6 weeks, but lymphopenia occurred with 200 parts/106. An increase in the concentration of THI to 400 parts/106 in the group on the lowest dose resulted in lymphopenia. An increase in dosagein two groups of mice, to 1000 and 2000 parts/106, resulted in marked lymphopenia. The number of neutrophils, eosinophils and monocytes remained unchanged throughout the experiment. Measurement of the proportions of CD4(L3T4)+ and CD8(Ly2)+ lymphocytes in lymph nodes from mice on high doses of THI did not show a selective depression of either subset, although both were increased relative to non‐T cells. THI causes a selective lymphopenia in mice, as in rats, but at relatively higher doses, and merits investigation in mice as an experimental treatment for states of lymphocyte excess or overactivity.
Association of maturation of the small intestine at weaning with mucosal mast cell activation in the rat
Authors: Cummins AG , Munro GH , Miller HRP , Ferguson A
Published: July 2007

Maturation of the small intestine at weaning has some features in common with immunological reactions involving the gut mucosa. Mucosal mast cell (MMC) activation is a prominent feature of both IgE and cell‐mediated mucosal immune responses. MMC activation was therefore studied during the weaning period by measurement of rat mucosal mast cell protease II (RMCPII) release into the systemic circulation as well as MMC counts and jejunal RMCPII content. Maturation of the small intestine was measured by changes in villus and crypt length, and in crypt cell production rate (CCPR). At 3 weeks of age, serum RMCPII increased 17‐fold and MMC showed features of degranulation. At the time of weaning (2–4 weeks), villus and crypt length and CCPR increased progressively to adult values. After weaning, serum RMCPII declined slowly to normal adult levels and MMC regained a normal appearance. This study showed a close association between MMC activation and maturation of the small intestine during the weaning period.
Resistance to cutaneous leishmaniasis in nude mice injected with L3T4+ T cells but not with Ly‐2+ T cells
Authors: Moll H , Scollay R , Mitchell GF
Published: July 2007

The importance of T cells in resistance to infection with the intracellular protozoan parasite Leishmania major is substantiated by the susceptibility to infection of athymic nude mice of both resistant and susceptible strains. However, the relative roles of different T cell subpopulations remain controversial. In order to address this issue, selected L3T4+ Ly‐2− or L3T4− Ly‐2+ T cell subpopulations from normal mice were adoptively transferred into athymic nude recipients of the same strain, and their capacity to mediate host‐protective immunity against infection with L. major promastigotes was determined. In experiments with mice of different inbred strains, reconstitution with L3T4+ Ly‐2− cells rendered the nude mice completely resistant to cutaneous leishmaniasis, whereas L3T4− Ly‐2+ cells failed to do so. Partial protection in some recipients of large numbers of Ly‐2+ cells could be ascribed to contamination of the transferred inoculum with L3T4+ cells. Thus, resistance to L. major infection in reconstituted nude mice can be promoted by L3T4+ T cells in the absence of detectable Ly‐2+ T cells.
Presence and characterization of lymphocytotoxins in acute and chronic Plasmodium berghei malaria
Authors: Wangoo A , Ganguly NK , Mahajan RC
Published: July 2007

The role of lymphocytotoxic antibodies in elimination of lymphocytes and characterization of these antibodies during Plasmodium berghei infection was examined in BALB/c mice. When assayed at l5°, an increase in lymphocytotoxic levels above base line values was detected in acute infection when parasitaemia exceeded 10%. There was an increase in lymphocytotoxins with increase in parasitaemia to a plateau beyond 25% parasitaemia. When assayed at 37°, lymphocytotoxic activity during acute infection was lower than at 15° but the increase detected was significant. During chronic infection there was a lower increase in the activity detected at 15° and no significant increase in activity assayed at 37° (P>0·05). In addition, peripheral blood lymphocyte counts also dropped during acute infection while there was little change in lymphocyte numbers in the chronic infection group. The lymphocytotoxic antibodies present in sera of infected mice were predominantly of IgM class during acute infection and IgM or IgG class during chronic infection. The relevance of these observations to plasmodium infection is discussed.
Involvement of O2 radicals in ‘autoimmune’ diabetes
Authors: Nomikos IN , Wang Y , Lafferty KJ
Published: July 2007

Spontaneous diabetes in the non‐obese diabetic (NOD) mice is a CD4 T cell‐dependent process. We have suggested that specific β cell destruction results from free radical production at the site of islet inflammation; oxygen radicals are produced by activated inflammatory cells. We reported here that in vivo treatment of spontaneously diabetic NOD mice with the enzyme superoxide dismutase (2000 U for seven injections) and catalase (40 000 U for seven injections) protects islet tissue from disease recurrence following transplantation into spontaneously diabetic mice. Similar results were obtained when animals were treated with either enzyme alone. This effect was dose‐dependent and little protection was observed when the dose of enzyme was reduced four‐fold. These results indicate that oxygen metabolites, specially superoxide and hydrogen peroxide, are directly involved in the pathogenesis of immunology mediated diabetes.
Localization of a 23 000 MW antigen of Cryptosporidium by immunoelectron microscopy
Authors: Lumb R , Smith PS , Davies R , O'Donoghue PJ , Atkinson HM , Lanser JA
Published: July 2007

Rabbit antiserum was raised against a 23 000 molecular weight (MW) antigen prepared from Cryptosporidium oocysts by electro‐elution from polyacrylamide gels. The antiserum was tested for specificity by immunoblotting against solubilized oocyst preparations. Several antigens including the 23 000 MW antigen were recognized suggesting that it shared common epitopes with higher MW proteins. The antiserum was then used in conjunction with a protein A‐colloidal gold conjugate to locate antigenic sites within exogenous and endogenous developmental stages of Cryptosporidium. The pellicles of both sporozoites and merozoites exhibited specific labelling, particularly around their anterior ends. No specific labelling was observed for any other membrane determinants or organelles in these or other life cycle stages.
Augmentation of recombinant interleukin‐2‐dependent murine macrophage‐mediated tumour cytotoxicity by recombinant tumour necrosis factor‐α
Authors: Kos FJ
Published: July 2007

The activation of murine macrophages by recombinant human interleukin‐2 (rH‐IL‐2) alone or in combination with recombinant human tumour necrosis factor‐α (rH‐TNF) was studied. Mouse peritoneal exudate macrophages were activated in vitro to the tumouricidal state. Macrophage treatment with rH‐IL‐2 alone slightly enhanced cytotoxic activity against B16 melanoma cells. Synergism was observed when macrophages were treated with rH‐IL‐2 and rH‐TNF, either when applied sequentially or when both agents were given at the same time.
Hydroxychavicol, a novel betel leaf component, inhibits platelet aggregation by suppression of cyclooxygenase, thromboxane production and calcium mobilization
Authors: Chang M C , Uang B J , Tsai C Y , Wu H L , Lin B R , Lee C S , Chen Y J , Chang C H , Tsai Y L , Kao C J , Jeng J H
Published: July 2007

Background and purpose:

Platelet hyperactivity is important in the pathogenesis of cardiovascular diseases. Betel leaf (PBL) is consumed by 200‐600 million betel quid chewers in the world. Hydroxychavicol (HC), a betel leaf component, was tested for its antiplatelet effect.

Experimental approach:

We tested the effect of HC on platelet aggregation, thromboxane B2 (TXB2) and reactive oxygen species (ROS) production, cyclooxygenase (COX) activity, ex vivo platelet aggregation and mouse bleeding time and platelet plug formation in vivo. The pharmacokinetics of HC in rats was also assessed.

Key results:

HC inhibited arachidonic acid (AA) and collagen‐induced platelet aggregation and TXB2 production. HC inhibited the thrombin‐induced TXB2 production, but not platelet aggregation. SQ29548, suppressed collagen‐ and thrombin‐induced TXB2 production, but not thrombin‐induced platelet aggregation. HC also suppressed COX‐1/COX‐2 enzyme activity and the AA‐induced ROS production and Ca2+ mobilization. HC further inhibited the ex vivo platelet aggregation of platelet‐rich plasma (>100 nmole/mouse) and prolonged platelet plug formation (>300 nmole/mouse) in mesenteric microvessels, but showed little effect on bleeding time in mouse tail. Moreover, pharmacokinetics analysis found that more than 99% of HC was metabolized within 3 min of administration in Sprague‐Dawley rats in vivo.

Conclusions and implications:

HC is a potent COX‐1/COX‐2 inhibitor, ROS scavenger and inhibits platelet calcium signaling, TXB2 production and aggregation. HC could be a potential therapeutic agent for prevention and treatment of atherosclerosis and other cardiovascular diseases through its anti‐inflammatory and antiplatelet effects, without effects on haemostatic functions.

British Journal of Pharmacology (2007) 152, 73–82; doi:10.1038/sj.bjp.0707367
Continuum mesoscopic framework for multiple interacting species and processes on multiple site types and/or crystallographic planes
Authors: Chatterjee Abhijit , Vlachos Dionisios G.
Published: July 2007

While recently derived continuum mesoscopic equations successfully bridge the gap between microscopic and macroscopic physics, so far they have been derived only for simple lattice models. In this paper, general deterministic continuum mesoscopic equations are derived rigorously via nonequilibrium statistical mechanics to account for multiple interacting surface species and multiple processes on multiple site types and/or different crystallographic planes. Adsorption, desorption, reaction, and surface diffusion are modeled. It is demonstrated that contrary to conventional phenomenological continuum models, microscopic physics, such as the interaction potential, determines the final form of the mesoscopic equation. Models of single component diffusion and binary diffusion of interacting particles on single-type site lattice and of single component diffusion on complex microporous materials’ lattices consisting of two types of sites are derived, as illustrations of the mesoscopic framework. Simplification of the diffusion mesoscopic model illustrates the relation to phenomenological models, such as the Fickian and Maxwell-Stefan transport models. It is demonstrated that the mesoscopic equations are in good agreement with lattice kinetic Monte Carlo simulations for several prototype examples studied.
Direct numerical simulation of the drag-reducing turbulent boundary layer of viscoelastic fluid
Authors: Tamano Shinji , Itoh Motoyuki , Hoshizaki Kenichi , Yokota Kazuhiko
Published: July 2007

Direct numerical simulation of a zero-pressure gradient drag-reducing turbulent boundary layer of homogeneous viscoelastic fluids was performed using constitutive equation models such as the Oldroyd-B and Giesekus models. Mean velocity profiles and turbulence statistics at the different streamwise locations were discussed using both inner and outer scaling. The maximum drag reduction ratio for the Oldroyd-B model, which has the higher elongational viscosity, is larger than for the Giesekus model. The distinct difference in turbulence statistics near the wall between the Oldroyd-B model and Newtonian fluid is observed, as reported in the drag-reducing turbulent channel flow, while in the outer region, distributions of turbulence statistics for the Oldroyd-B model with a drag reduction ratio of about 40% are similar to those for Newtonian fluid. The production term for the turbulent boundary layer does not correspond to the amount of drag reduction, which is consistent with the fact that the streamwise turbulence intensity profile is not a direct indication of the drag reduction. The contribution of the advection term to the budget of streamwise Reynolds normal stress, which does not appear for the turbulent channel flow, is not negligible near the wall for the Oldroyd-B model. For the Oldroyd-B model with a maximum drag reduction ratio of 42%, we can see that quasi-streamwise vortices are weakened and become larger in the streamwise direction, compared to Newtonian fluid. On the other hand, quasi-streamwise vortices for the Giesekus model with a maximum drag reduction ratio of 16% are slightly larger than those for Newtonian fluid. These modifications of near-wall coherent structures are explained by the profile of the trace of mean viscoelastic stress and the elastic energy theory presented by Min et al. [J. Fluid Mech. 486, 213 (2003)] for the drag-reducing turbulent channel flow.
Low temperature perovskite crystallization of 70%PbMg1∕3Nb2∕3O3–30%PbTiO3 thin films deposited by sputtering and their electrical performance evaluation
Authors: Detalle M. , Rémiens D. , Wang G. , Roussel P. , Dkhil B.
Published: July 2007

Pb Mg 1 ∕ 3 Nb 2 ∕ 3 O 3 – Pb Ti O 3 films were deposited on silicon by sputtering, followed by an annealing treatment. The authors demonstrate the pure perovskite phase may be obtained at very low temperature (400°C) without any pyrochlore phase. The existence of an interfacial layer of Pb2Nb2O7 structure is evidenced. They suggest that such phase serves as seed layer which promotes the apparition of the perovskite phase. The permittivity of the films annealed at 450°C is high (600) compared to most dielectric materials obtained at this temperature. The electromechanic properties (d33=50pC∕m) are also suitable for microelectromechanical system applications with a thermal treatment compatible with the above integrated circuits.
Acoustic wave propagation and internal fields in rigid frame macroscopically inhomogeneous porous media
Authors: De Ryck L. , Lauriks W. , Fellah Z. E. A. , Wirgin A. , Groby J. P. , Leclaire P. , Depollier C.
Published: July 2007

A wave propagation model in macroscopically inhomogeneous porous media is derived from the alternative Biot’s theory of 1962. As a first application, the wave equation is reduced and solved in the case of rigid frame inhomogeneous porous materials. The pressure field, as well as the reflection and transmission coefficients, are obtained numerically using a wave splitting and “transmission” Green’s functions approach (WS-TGF). To validate both the wave equation and the method of resolution at normal and oblique incidence, results obtained by the WS-TGF method are compared to those calculated by the classical transfer matrix method and to experimental measurements for a known two-layered porous material, considered as a single inhomogeneous layer. Discussions are then given of the reflection and transmission coefficients for various inhomogeneity profiles as well as of the internal pressure field.
Correlation of reaction sites during the chlorine extraction by hydrogen atom from Cl∕Si(100)-2×1
Authors: Hsieh Ming-Feng , Chung Jen-Yang , Lin Deng-Sung , Tsay Shiow-Fon
Published: July 2007

The Cl abstraction by gas-phase H atoms from a Cl-terminated Si(100) surface was investigated by scanning tunneling microscopy (STM), high-resolution core level photoemission spectroscopy, and computer simulation. The core level measurements indicate that some additional reactions occur besides the removal of Cl. The STM images show that the Cl-extracted sites disperse randomly in the initial phase of the reaction, but form small clusters as more Cl is removed, indicating a correlation between Cl-extracted sites. These results suggest that the hot-atom process may occur during the atom-adatom collision.
Silicon film formation by chemical transport in atmospheric-pressure pure hydrogen plasma
Authors: Ohmi Hiromasa , Kakiuchi Hiroaki , Hamaoka Yoshinori , Yasutake Kiyoshi
Published: July 2007

To prepare polycrystalline silicon (poly-Si) films at low temperatures (<400°C) with high deposition rate, we propose a chemical transport method using atmospheric-pressure pure hydrogen plasma, called the atmospheric-pressure enhanced chemical transport method. In this method, high-pressure (200–760Torr) stable glow plasma of pure hydrogen was generated by a 150MHz very high frequency power between the two parallel electrodes less than 2mm apart. One of the electrodes is composed of the cooled Si solid source and the other the heated substrate (200–400°C). According to the temperature dependence of hydrogen etching rate of Si, SiHx species are mainly generated at the cooled Si solid source by hydrogen atoms. These species are again decomposed in the plasma, transported to the substrate to form Si films. In the present experiments on poly-Si film formation, a high deposition rate of 300nm∕min was achieved at 400°C, and nearly ideal utilization efficiencies (>93%) of Si solid source was realized in every condition. Si grains formed on a (001) Si substrate revealed anisotropic morphology elongated along ⟨110⟩ directions, and most of them had columnar structures epitaxially grown to the thickness of 2μm even at 200°C.
Effect on ultrasonic generation of a backplate in electromagnetic acoustic transducers
Authors: Jian X. , Dixon S. , Edwards R. , Quirk K. , Baillie I.
Published: July 2007

When constructing an electromagnetic acoustic transducer (EMAT), it is often desirable to incorporate a permanent magnet behind the EMAT coil and an electrically conducting backplate between the coil and the magnet to prevent ultrasonic generation in the magnet by the current in the EMAT coil. This paper investigates the effect of the backplate on the generation of the eddy current and the resultant ultrasonic wave in the sample. We develop analytical expressions for the important physical phenomena and show that the backplate tends to reduce the amplitude of the eddy current and ultrasonic wave generated in the sample. This is dependent on the liftoff between the coil and the sample, and the air gap between the coil and the backplate. Results from modeling have been verified by our experimental measurements.
Evolution of InAs nanostructures grown by droplet epitaxy
Authors: Zhao C. , Chen Y. H. , Xu B. , Jin P. , Wang Z. G.
Published: July 2007

The authors report the growth evolution of InAs dot and ring nanostructures with the indium deposition amount on GaAs (001) by droplet molecular beam epitaxy. There is a critical flux for the indium to form InAs dots even when there is no droplet. When the flux exceeds a critical value, In droplets form, which act as nucleation centers for the formation of InAs rings.
Amplified spontaneous emission from dye-doped polymer film sandwiched by two opal photonic crystals
Authors: Jin Feng , Song Yang , Dong Xian-Zi , Chen Wei-Qiang , Duan Xuan-Ming
Published: July 2007

The authors observed amplified spontaneous emission (ASE) from dye-doped polymer film sandwiched by two opal photonic crystals (PhCs). The ASE effect occurred at 599nm with a full width at half maximum of about 5.1nm, which corresponds to the L-point gap edge of the opal PhCs. Photoluminescence lifetimes of both dye-doped polymer films with and without opal PhCs were measured and corroborated that the ASE of the dye-doped polymer film emission is due to the presence of the photonic stop band.
New Insights into the Internationalization of Producer Services: Organizational Strategies and Spatial Economies for Global Headhunting Firms
Authors: Faulconbridge James R , Hall Sarah J E , Beaverstock Jonathan V
Published: July 2007

This paper uses the exemplar of global headhunting firms to provide new insights into the intricacies of internationalization and related ‘spatial economies’ of producer services in the world economy. In particular, we unpack the complex relationships between the organizational rationale for, the selected mode of, and future benefits gained by internationalization, as headhunting firms seek and create new geographical markets. We achieve this through an analysis of headhunting firm-specific case study data that detail the evolving way such firms organize their differential strategic growth (organic, merger and acquisition, and alliances/network) and forms (wholly owned, networked, or hybrid). We also highlight how, as elite labour market intermediaries, headhunted are important, yet understudied, actors within the (re)production of a ‘softer’, ‘knowledgeable’ capitalism. Our argument, exemplified through detailed mapping of the changing geographies of headhunting firms between 1992 and 2005, demonstrates the need for complex and blurred typologies of internationalization and similarly complex internationalization theory.
Diarrhoeagenic Escherichia coli and other causes of childhood diarrhoea: a case–control study in children living in a wastewater-use area in Hanoi, Vietnam
Authors: Hien Bui Thi Thu , Trang Do Thuy , Scheutz Flemming , Cam Phung Dac , Mølbak Kåre , Dalsgaard Anders
Published: July 2007

A case–control study was conducted to identify the aetiology of diarrhoeal diseases in pre-school children in a suburban area of Hanoi where the use of untreated wastewater in agriculture and aquaculture is a common practice. Stool specimens and clinical information were collected from 111 pairs of children with diarrhoea and healthy controls. A total of 73 cases (66 %) and 41 controls (36 %) had an enteric pathogen. The pathogens most often associated with diarrhoea were rotavirus (17 % of cases) and Entamoeba histolytica (15 %), followed by Shigella (5 %). Diarrhoeagenic Escherichia coli (DEC) was found in 23 % of both patients and controls. Characterization of DEC by serotyping, antimicrobial susceptibility test and PFGE showed that DEC represented by different pathotypes belonged to various serotypes. Except for three enterotoxigenic E. coli strains, typing by PFGE revealed no correlation between pathotype and serotype of DEC strains. This suggests a high prevalence of a variety of DEC subtypes in this area. For this particular region, vaccine development strategies targeting rotavirus and Shigella are likely to be of public health benefit, whereas the role of DEC and preventive measures need to be further elaborated.
Identification of Mycobacterium using the EF-Tu encoding (tuf) gene and the tmRNA encoding (ssrA) gene
Authors: Mignard Sophie , Flandrois Jean-Pierre
Published: July 2007

The partial nucleotide sequences encoding the elongation factor Tu (tufgene) (652 bp) and transfer-mRNA (tmRNA orssrAgene) (340 bp) were determined to assess the suitability of these two genes as phylogenetic markers for the classification of mycobacteria, and thus as alternative target molecules for identifying mycobacteria. A total of 125 reference strains of the genusMycobacteriumand 74 clinical isolates were amplified by PCR and sequenced. Phylogenies of the two genes constructed by the neighbour-joining method were created and compared to a concatenated tree of 16S rDNA,hsp65,sodAandrpoBgenes. The phylogenetic trees revealed the overall natural relationships amongMycobacteriumspecies. The tmRNA phylogeny was similar to that of 16S rDNA, with low resolving power. Thetufgene provided better resolution of each mycobacterial species, with a phylogeny close to that ofhsp65. However, none of these methods differentiated between the members of theMycobacterium tuberculosiscomplex or the subspecies of theMycobacterium aviumcomplex. The correct identification of clinical isolates confirms the interest of these genes, especiallytuf. It is suggested from these findings that tmRNA might be useful as another housekeeping gene in a polyphyletic approach toMycobacteriumspecies, but not as a first-line marker of species.tufgene analysis suggests that this gene could be used effectively for phylogenetic analysis and to identify mycobacteria.
Chlamydophila psittaci genotype E/B transmission from African grey parrots to humans
Authors: Harkinezhad Taher , Verminnen Kristel , Van Droogenbroeck Caroline , Vanrompay Daisy
Published: July 2007

Thirty-six birds from a parrot relief and breeding centre, as well as the manager, were examined for the presence of Chlamydophila psittaci. In the relief unit, 5 of 20 African grey parrots showed depression, ruffled feathers, loss of weight and mild dyspnoea. The birds received no antibiotic treatment. Birds of the breeding unit, 14 blue and gold macaws and 2 green-winged macaws, were healthy. They received doxycycline at the start of each breeding season. The manager complained of shortness of breath but took no medication. Using a nested PCR enzyme immunoassay (EIA), Cp. psittaci was detected in the faeces of all five sick birds, as well as in a nasal and pharyngeal swab from the manager. The veterinarian and her assistant became infected while sampling the parrots, as pharyngeal and nasal swabs from both were positive by nested PCR/EIA after visiting the parrot relief and breeding centre, but they showed no clinical signs of infection. Bacteria could be isolated from three of five nested PCR/EIA-positive birds, the manager and the veterinarian, but not from the veterinary assistant. Using an ompA genotype-specific real-time PCR, Cp. psittaci genotype E/B was identified as the transmitted strain. All breeding birds tested negative for Cp. psittaci. This is believed to be the first report on Cp. psittaci genotype E/B transmission from parrots to humans. In contradiction to genotype A strains, which are thought to be highly virulent to both birds and men, the currently described genotype E/B strain apparently caused no severe clinical symptoms in either parrots or humans.
Antineoplastic activity of 2‐methoxyestradiol in human pancreatic and gastric cancer cells with different multidrug‐resistant phenotypes
Authors: Schumacher Guido , Hoffmann Janine , Cramer Thorsten , Spinelli Antonino , Jacob Dietmar , Bahra Marcus , Pratschke Johann , Pfitzmann Robert , Schmidt Sven , Lage Hermann
Published: July 2007

Background and Aim:  Chemoresistance often leads to loss of the last treatment option for cancer. 2‐Methoxyestradiol (2‐ME2) has been shown to inhibit tumor growth. The aim was to examine the efficacy of 2‐ME2 on multidrug‐resistant human cells from pancreatic and gastric cancer.

Methods:  We investigated the impact of 2‐ME2 on multidrug‐resistant cells derived from human pancreatic and gastric cancer cells that were positive or negative for the MDR1‐gene.

Results:  In pancreatic cancer cells, growth inhibition was 57% in parental, 72% in MDR1‐negative and 87% in MDR1‐positive cells after 1 μmol/L 2‐ME2. In gastric cancer cells we found a growth inhibition of 75% in parental, 82% in MDR1‐positive and 95% in MDR1‐negative cells. Strong induction of apoptosis was induced after a low dose of 2‐ME2. No significant difference in the amount of apoptotic cells was observed between parental and multidrug‐resistant cells of both tumor types. The number of apoptotic cells after 2‐ME2 ranged from 7.5% in parental gastric cancer cells to 20.1% in MDR1‐negative gastric cancer cells.

Conclusion:  2‐ME2 may therefore have clinical application for chemoresistant cancer.
Epidemiological investigation in outpatients with symptomatic gastroesophageal reflux from the Department of Medicine in Zhejiang Province, east China
Authors: Li You‐Ming , Du Juan , Zhang Hong , Yu Chao‐Hui
Published: July 2007

Background and Aim:  To elucidate the epidemiology of gastroesophageal reflux disease (GERD) symptoms in outpatients from the Department of Medicine in 10 hospitals in Zhejiang Province, east China.

Methods:  A cross‐sectional survey in the cluster random sample was conducted from November 2004 to June 2005 using a validated Chinese version of the reflux disease questionnaire and other items recording the demographic characteristics for GERD symptoms. The statistical analysis was performed with SPSS 13.0 programs.

Results:  A total of 15 283 outpatients from the Department of Medicine were investigated. The prevalence of GERD symptoms was 7.28% (95% confidence interval [CI], 6.87%, and 7.69%) with the prevalence rate increasing with age (P < 0.001), which was higher in men (7.79%, 95% CI: 7.20%, 8.38%) than in women (6.73%, 95% CI: 6.18%, 7.28%; χ2 = 5.81, P < 0.05). The prevalence rate of the gastrointestinal symptoms in GERD symptoms, including epigastric discomfort, nausea, retrosternal pain, belching, globus sensation, loss of appetite, excessive salivation, vomiting, wheezing cough, weight loss, and dysphagia were all higher than the non‐GERD patients (P < 0.0001). In the GERD patients, the prevalence of diseases, such as pharyngolaryngitis, snoring, bronchitis, liver disease, and gallbladder disease were all higher than the non‐GERD patients (P < 0.01). The multiple logistic regression analysis showed that old age, night‐shift work, heavy work burdens, single or divorced people, increase intake of greasy or sweet foods, excessive eating, and constipation were independent risk factors associated with GERD symptoms.

Conclusion:  GERD has a high prevalence in China and its main associated factors include respiratory, laryngopharyngeal and dental disorders, sex, anthropometrical variables, and social–psychological characteristics.
Primary biliary cirrhosis in Singapore: Evaluation of demography, prognostic factors and natural course in a multi‐ethnic population
Authors: Wong Reuben‐Km , Lim Seng‐Gee , Wee Aileen , Chan Yiong‐Huak , Aung Myat‐Oo , Wai Chun‐Tao
Published: July 2007

Background and Aim:  Primary biliary cirrhosis (PBC) is infrequent in Asians. Among Asian patients with PBC, information on natural course is scarce. The aim of this study was to study the clinical course and prognosticators among Asians with PBC.

Methods:  During 1990–2005, patients diagnosed with PBC at the National University Hospital, Singapore, constituted the retrospective cohort. Their demographic characteristics were evaluated. To evaluate the prognostic factors and natural course, two outcome measures were assessed: hepatic decompensation and death or liver transplant. Multivariate analysis was undertaken to identify factors associated with hepatic decompensation and terminal event (death or liver transplantation).

Results:  Thirty‐four PBC patients aged 56.8 ± 1.8 years (mean ± SEM) of whom 32 (94%) were women were included. Thirty‐two (94%) of them were of Chinese origin. At presentation, 18 (53%) were symptomatic in the form of jaundice (n = 9, 26.5%), pruritus (n = 6, 17.6%) and fatigue (n = 5, 14.7%). During 4.80 ± 0.7 (range 0.02–15.03) years follow up, 6/16 (37.5%) asymptomatic patients developed symptoms. After 5 years, 17.6% (n = 6) and 8.8% (n = 3) had hepatic decompensation and terminal event, respectively. Sicca syndrome was present in 26% (n = 9) of patients. Multivariate analysis revealed that serum bilirubin level at presentation was the sole determinant of decompensation. Rate of change of laboratory indices did not predict either event.

Conclusion:  In Singapore, Chinese women constitute most of the PBC patients. Elevated serum bilirubin level at presentation was the sole predictive marker associated with dismal outcome.
Low‐dose intravenous pantoprazole for optimal inhibition of gastric acid in Korean patients
Authors: Oh Jung‐Hwan , Choi Myung‐Gyu , Dong Mi‐Sook , Park Jae‐Myung , Paik Chang‐Nyol , Cho Yu‐Kyung , Jeong Jeong‐Jo , Lee In‐Seok , Kim Sang‐Woo , Han Sok‐Won , Choi Kyu‐Yong , Chung In‐Sik
Published: July 2007

Background and Aim:  Proton‐pump inhibitor (PPI) therapy for bleeding ulcers is more efficacious in Asian patients than in non‐Asian patients. The aim of this study was to evaluate the efficacy of various doses of pantoprazole on intragastric acidity in Korean patients.

Methods:  A prospective randomized study was conducted in 52 patients either with bleeding peptic ulcers after successful endotherapy or who received endoscopic mucosal resection for gastric neoplasms. Patients were randomized into two doses of intravenous pantoprazole: 40 mg q.d. and 40 mg b.i.d. We compared these results with our preliminary study utilizing high‐dose pantoprazole (80 mg + 8 mg/h). The potential contribution of CYP2C19 genetic polymorphisms and the presence of Helicobacter pylori were also assessed.

Results:  Pantoprazole 40 mg b.i.d. and high‐dose pantoprazole demonstrated better inhibition of intragastric acid than pantoprazole q.d. (P < 0.05). The pantoprazole 40 mg q.d. group exhibited significant variations in acid inhibition correlating with CYP2C19 genotype. Median 24 h pH values did not differ significantly between the pantoprazole b.i.d. and high‐dose pantoprazole groups, regardless of H. pylori infection status. A median intragastric pH < 6.0 was observed in only three of 28 patients in the 40 mg b.i.d. group; these three patients were extensive metabolizers.

Conclusion:  A 40 mg b.i.d. dose of pantoprazole is sufficient to maintain pH > 6.0 in Korean patients, except for patients with extensive metabolizing CYP2C19 genotypes.
Inhibition of TXA2synthesis with OKY‐046 improves liver preservation by prolonged hypothermic machine perfusion in rats
Authors: Xu Hongzhi , Lee Charles Y , Clemens Mark G , Zhang Jian X
Published: July 2007

Background and Aim: We previously reported that hypothermic machine perfusion (HMP) for liver preservation is feasible, but hepatic microcirculatory dysfunction and significant liver damage remain major obstacles in its application when the preservation is extended to 24 h. The underlying injury mechanism is not well understood. The present study sought to investigate the role of thromboxane A2(TXA2) in the pathogenesis of liver injury after prolonged HMP.

Methods: Livers isolated from Sprague–Dawley rats were subjected to continuous machine perfusion with University of Wisconsin (UW) solution at a flow rate of 0.4 mL/min/g liver at 4°C for 24 h. A specific TXA2synthase inhibitor, OKY‐046 (OKY), was added to UW solution during the preservation period and to the Krebs–Henseleit buffer during reperfusion. The performance of the livers after preservation was evaluated using an isolated liver perfusion system with Krebs–Henseleit buffer at a flow rate of 15 mL/min at 37°C for 30 min.

Results: Prolonged HMP induced a significant release of TXA2into the portal circulation as indicated by markedly increased levels of TXB2in the perfusate during reperfusion (at 30 min, 1447.4 ± 163.6 pg/mLvs50.91 ± 6.7 pg/mL for control). Inhibition of TXA2synthesis with OKY significantly decreased releases of TXA2(69.8 ± 13.4 pg/mL) concomitant with reduced lactate dehydrogenase (LDH) releases (at 30 min, HMP + OKY: 144.9 ± 27.9 U/L; HMP: 369.3 ± 68.5 U/L; simple cold storage or SCS: 884.4 ± 80.3 U/L), decreased liver wet/dry weight ratio (HMP + OKYvsSCS and HMP: 3.6 ± 0.3vs4.4 ± 0.1 and 3.9 ± 0.2, respectively) and increased hyaluronic acid uptake (at 30 min, HMP + OKYvsSCS, HMP: 33.1 ± 2.9%vs13.9 ± 3.6%, 18.6 ± 2.4%, respectively). Liver histology also showed significant improvement in tissue edema and hepatocellular necrosis with OKY compared with HMP without OKY.

Conclusion: The results demonstrate that TXA2is involved in the development of hepatocellular injury induced by HMP, and inhibition of TXA2synthesis during preservation and reperfusion protects liver hepatocytes and sinusoidal endothelial cells from injuries caused by prolonged HMP.
Self‐esteem and culture: Differences in cognitive self‐evaluations or affective self‐regard?
Authors: Cai Huajian , Brown Jonathon D. , Deng Ciping , Oakes Mark A.
Published: July 2007

Although people from East Asian countries consistently report lower self‐esteem than do those from Western countries, the origins of this difference are unclear. We conducted two studies to illuminate this issue. Study 1 found that Chinese participants appraised themselves less positively than American participants on a cognitive measure of self‐evaluations, but cultural differences were absent on a measure of affective self‐regard. Moreover, cultural differences in global self‐esteem were eliminated once cognitive self‐evaluations were statistically controlled. Study 2 found that cultural differences in modesty underlie cultural differences in cognitive self‐evaluations. These findings suggest that Chinese feel as positively toward themselves as Americans do, but are less inclined to evaluate themselves in an excessively positive manner.
Pulsed dye laser: what's new in non‐vascular lesions?
Authors: Karsai S , Roos S , Hammes S , Raulin C
Published: July 2007

Background and objective  In dermatology, the pulsed dye laser (PDL) is the therapeutic instrument of choice for treating most superficial cutaneous vascular lesions. In addition, clinical experience over the last decade allowed us to treat patients with an ever increasing number of non‐vascular indications. The purpose of this report is to summarize and critically appraise the scientific evidence that support the role of PDL in treating non‐vascular skin lesions.

Methods  A literature‐based study has been conducted, including the review of publications over the period January 1995 to December 2006, using the Medline Database. We also included our own experience in managing non‐vascular lesions with the PDL. Four sets of preoperative and postoperative photos are presented.

Results  For viral skin lesions, PDL proved to be an alternative to other therapy options. This applies particularly to periungual warts and mollusca contagiosa. The mechanism of PDL with inflammatory dermatoses has not yet been elucidated. The effect seems to be better if there is a vascular component to the disease. With most of these indications (such as psoriasis and acne), PDL currently plays a rather minor or complementary role. Regarding collagen remodelling (hypertrophic scars, keloids, stretch marks, and skin rejuvenation), the question of whether a therapy makes sense or not has to be decided from case to case.

Conclusion  With PDL, it is possible to achieve good results with numerous, partly less well‐known indications (i.e. lupus erythematosu). With other diseases, PDL has so far been considered to be a complementary therapy method or to be in an experimental state.
Correlation of serum IL‐6, IL‐8 and IL‐10 levels with clinicopathological features and prognosis in patients with diffuse large B‐cell lymphoma
Authors: NAČINOVIĆ‐DULETIĆ A. , ŠTIFTER S. , DVORNIK Š. , ŠKUNCA Ž. , JONJIĆ NIVES
Published: July 2007

Cytokines play important roles in the pathogenesis of lymphomas. This study aimed to determine the relationship(s) between serum levels of interleukin (IL)‐6, IL‐8 and IL‐10, measured by enzyme‐immunoassay, and the clinical characteristics and outcomes in 46 untreated patients with diffuse large B‐cell lymphoma (DLBCL). Serum IL‐6, IL‐8 and IL‐10 levels were higher in DLBCL patients than in control subjects. Elevated levels of IL‐6, IL‐8 and IL‐10 correlated with more adverse disease features. Consequently, patients with elevated IL‐6, IL‐8 and IL‐10 levels prior to treatment had a lower response to therapy. Furthermore, those with elevated IL‐6 and IL‐10 levels had poor median, 3‐year and 5‐year survival, while elevated serum IL‐8 level did not correlate with overall survival. Worse survival was also confirmed in patients with combined elevated pretreatment serum levels of IL‐6, IL‐8 and IL‐10 (none, one, two or three elevated). Multivariate analysis identified elevated values of IL‐6 and IL‐10 and response to therapy as significant predictors for overall survival. Serum levels of IL‐6, IL‐8 and IL‐10 before treatment of patients with newly diagnosed DLBCL may give some insight into the possible prognosis and thus facilitate the decisions regarding therapeutic approaches for individual patients.
Frequency response of human vestibular reflexes characterized by stochastic stimuli
Authors: Dakin Christopher J. , Son Gregory M. Lee , Inglis J. Timothy , Blouin Jean‐Sébastien
Published: July 2007

Stochastic vestibular stimulation (SVS) can be used to study the postural responses to unpredictable vestibular perturbations. The present study seeks to determine if stochastic vestibular stimulation elicits lower limb muscular responses and to estimate the frequency characteristics of these vestibulo‐motor responses in humans. Fourteen healthy subjects were exposed to unpredictable galvanic currents applied on their mastoid processes while quietly standing (±3 mA, 0–50 Hz). The current amplitude and stimulation configuration as well as the subject's head position relative to their feet were manipulated in order to determine that: (1) the muscle responses evoked by stochastic currents are dependent on the amplitude of the current, (2) the muscle responses evoked by stochastic currents are specific to the percutaneous stimulation of vestibular afferents and (3) the lower limb muscle responses exhibit polarity changes with different head positions as previously described for square‐wave galvanic vestibular stimulation (GVS) pulses. Our results revealed significant coherence (between 0 and 20 Hz) and cumulant density functions (peak responses at 65 and 103 ms) between SVS and the lower limbs' postural muscle activity. The polarity of the cumulant density functions corresponded to that of the reflexes elicited by square‐wave GVS pulses. The SVS–muscle activity coherence and time cumulant functions were modulated by current amplitude, electrode position and head orientation with respect to the subject's feet. These findings strongly support the vestibular origin of the lower limb muscles evoked by SVS. In addition, specific frequency bandwidths in the stochastic vestibular signal contributed to the early (12–20 Hz) and late components (2–10 Hz) of the SVS‐evoked muscular responses. These frequency‐dependent SVS‐evoked muscle responses support the view that the biphasic muscle response is conveyed by two distinct physiological processes.