bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancement of Macrophage Stimulation by Lipoteichoic Acid and the Costimulant Hemoglobin Is Dependent on Toll-Like Receptors 2 and 4
Authors: Cox Kathleen H. , Ofek Itzhak , Hasty David L.
Published: February 2007

Macrophage stimulation by lipoteichoic acid (LTA) and hemoglobin (Hb) requires Toll-like receptors 2 and 4 (TLR2 and -4). There are two distinct temporal phases of interleukin-6 (IL-6) production. The first results in a slight enhancement of IL-6 secretion in response to LTA plus Hb compared to that with LTA alone and is TLR4 independent. The second requires TLR4 and accounts for most of the additional stimulation seen with LTA plus Hb.
The Phase-Variable Allele of the Pilus Glycosylation Gene
pglA
Is Not Strongly Associated with Strains of
Neisseria gonorrhoeae
Isolated from Patients with Disseminated Gonococcal Infection
Authors: Power P. M. , Ku S. C. , Rutter K. , Warren M. J. , Limnios E. A. , Tapsall J. W. , Jennings M. P.
Published: February 2007

The
Neisseria gonorrhoeae pglA
gene has two alleles, one of which is phase variable. A previous study reported that all disseminated gonococcal infection (DGI) isolates contained the phase-variable allele and proposed a causal link. In the present study of 81 strains no absolute correlation between DGI and the phase-variable
pglA
allele was observed.
Neisseria gonorrhoeae
Catalase Is Not Required for Experimental Genital Tract Infection despite the Induction of a Localized Neutrophil Response
Authors: Soler-García Ángel A. , Jerse Ann E.
Published: February 2007

Neisseria gonorrhoeae
produces several antioxidant defenses, including high levels of catalase, which may facilitate the persistence during an inflammatory response via neutralization of H
2
O
2
produced by phagocytes. In vivo testing of the role of catalase in gonococcal survival is critical since several physiological factors impact interactions between
N. gonorrhoeae
and polymorphonuclear leukocytes (PMNs). Here we assessed the importance of gonococcal catalase in a surrogate model of female genital tract infection. Female BALB/c mice were treated with 17-β estradiol to promote susceptibility to
N. gonorrhoeae
and inoculated intravaginally with wild-type gonococci or a catalase (
kat
) deletion mutant. A localized PMN influx occurred in an average of 43 and 81% of mice infected with wild-type or
kat
mutant gonococci, respectively, and PMNs associated with numerous wild-type or catalase-deficient bacteria were observed in vaginal smears. The combined results of six experiments showed a significant difference in the number of days wild-type bacteria were recovered compared to the catalase-deficient gonococci. However, there was much variability between experiments, and we found no correlation between PMN influx, colonization load, and clearance of wild-type or
kat
mutant bacteria. Estradiol treatment did not impair bacterial uptake, the luminol-dependent chemiluminescence response, or the killing capacity of isolated murine PMNs against
N. gonorrhoeae
or
Staphylococcus aureus
. Our data suggest
N. gonorrhoeae
is not significantly challenged by H
2
O
2
produced by PMNs in the murine lower genital tract; alternatively, redundant defense mechanisms may protect the gonococcus from reactive oxygen species during infection.
Pet, a Non-AB Toxin, Is Transported and Translocated into Epithelial Cells by a Retrograde Trafficking Pathway
Authors: Navarro-García Fernando , Canizalez-Roman Adrián , Burlingame Kaitlin E. , Teter Ken , Vidal Jorge E.
Published: February 2007

The plasmid-encoded toxin (Pet) of enteroaggregative
Escherichia coli
is a 104-kDa autotransporter protein that exhibits proteolytic activity against the actin-binding protein α-fodrin. Intracellular cleavage of epithelial fodrin by Pet disrupts the actin cytoskeleton, causing both cytotoxic and enterotoxic effects. Intoxication requires the serine protease activity of Pet and toxin endocytosis from clathrin-coated pits. The additional events in the intracellular trafficking of Pet are largely uncharacterized. Here, we determined by confocal microscopy that internalized Pet is transferred from the early endosomes to the Golgi apparatus and then travels to the endoplasmic reticulum (ER). Pet associates with the Sec61p translocon before it moves into the cytosol as an intact, 104-kDa protein. This translocation process contrasts with the export of other ER-translocating toxins, in which only the catalytic A subunit of the AB toxin enters the cytosol. However, like intoxication with these AB toxins, Pet intoxication was inhibited in a subset of mutant CHO cell lines with aberrant activity in the ER-associated degradation pathway of ER-to-cytosol translocation. This is the first report which documents the cell surface-to-ER and ER-to-cytosol trafficking of a bacterial non-AB toxin.
The Glycan Moieties and the N-Terminal Polypeptide Backbone of a Fimbria-Associated Adhesin, Fap1, Play Distinct Roles in the Biofilm Development of
Streptococcus parasanguinis
Authors: Wu Hui , Zeng Meiqin , Fives-Taylor Paula
Published: February 2007

Fap1, a fimbria-associated glycoprotein, is essential for biofilm formation of
Streptococcus parasanguinis
and mediates bacterial attachment to saliva-coated hydroxylapatite, an in vitro tooth model (E. H. Froeliger and P. M. Fives-Taylor, Infect. Immun. 69:2512-2519, 2001; H. Wu and P. M. Fives-Taylor, Mol. Microbiol. 34:1070-1081, 1999; H. Wu et al., Mol. Microbiol. 28:487-500, 1998). Fap1 belongs to a growing family of high-molecular-weight serine-rich proteins found in streptococcal and staphylococcal species and possesses two serine-rich repeat regions. The glycan moiety of Fap1 appears to be O linked within the repeat regions (A. E. Stephenson et al., Mol. Microbiol. 43:147-157, 2002). In the present study, we identified a gene cluster immediately upstream of
fap1
that encodes three putative glycosyltransferases and one nucleotide-sugar synthetase-like protein. Inactivation of one glycosyltransferase gene
galT2
abolished the expression of two glycan epitopes; however, it did not alter bacterial ability to adhere to both SHA and saliva-conditioned biofilm surfaces. In contrast, the biofilms formed by the
galT2
mutant were shallow and had a 70% decrease in biomass accumulation, suggesting that these glycan moieties mediated by GalT2 are not required for the initial adhesion but are important for biofilm formation. A recombinant N-terminal Fap1 polypeptide was shown to interact with a 53-kDa salivary protein and block and displace bacterial attachment, further demonstrating the role of the Fap1 polypeptide in bacterial adhesion. Taken together, these results suggest that Fap1 glycosylation plays an important role in bacterial biofilm formation, whereas the nonglycosylated Fap1 peptide mediates bacterial initial attachment during the process of biofilm formation.
Influence of Neutropenia on the Course of Serotype 8 Pneumococcal Pneumonia in Mice
Authors: Marks Matthew , Burns Tamika , Abadi Maria , Seyoum Beza , Thornton Justin , Tuomanen Elaine , Pirofski Liise-anne
Published: February 2007

Polymorphoneutrophils (PMNs) are important effector cells in host defense against pneumonia. However, PMNs can also induce inflammation and tissue damage. To investigate the contribution of PMNs to host defense against pneumococcal pneumonia, we determined the effect of the PMN-depleting rat monoclonal antibody RB6-8C5 (RB6) on survival and inflammatory and cellular response in the lungs to a lethal intranasal infection with a serotype 8 pneumococcus in BALB/c mice. Control mice received rat immunoglobulin G (rIgG). Strikingly, the survival of RB6-treated mice was significantly prolonged compared to that of rIgG-treated mice. Although the numbers of CFU in the lungs were statistically similar in both groups 4, 24, and 32 h after infection, rIgG-treated mice developed higher levels of bacteremia, and histopathological examination of the lungs of infected mice revealed marked differences between RB6- and rIgG-treated mice. RB6-treated mice had focal, perivascular lesions without accompanying parenchymal inflammation, and rIgG-treated mice had diffuse, interstitial parenchymal inflammation. Lung homogenates from the rIgG-treated mice had more leukocytes and significantly more total and apoptotic PMNs as determined by fluorescence-activated cell sorter analysis with Annexin V and terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling staining of lung tissue samples. Studies with a pneumolysin-deficient mutant of the serotype 8 strain we used also demonstrated the prolonged survival of RB6- compared to rIgG-treated mice. Taken together, our findings suggest that PMNs enhance the likelihood of early death and alter the pathological response to pneumococcal lung infection in BALB/c mice with serotype 8 pneumonia without significantly affecting bacterial clearance or the cytokine response.
Bile Salts Stimulate Recruitment of IpaB to the
Shigella flexneri
Surface, Where It Colocalizes with IpaD at the Tip of the Type III Secretion Needle
Authors: Olive Andrew J. , Kenjale Roma , Espina Marianela , Moore David S. , Picking Wendy L. , Picking William D.
Published: February 2007

Shigella flexneri
uses its type III secretion apparatus (TTSA) to deliver invasins into human cells. This TTSA possesses an external needle with IpaD at its tip. We now show that deoxycholate promotes the stable recruitment of IpaB to the needle tip without inducing a rapid burst of type III secretion. The maintenance of IpaB at the needle tip requires a stable association of IpaD with the
Shigella
surface. This is the first demonstration of a translocator protein being stably associated with the TTSA needle.
InactivatedFrancisella tularensisLive Vaccine Strain Protects against Respiratory Tularemia by Intranasal Vaccination in an Immunoglobulin A-Dependent Fashion
Authors: Baron Shawn D. , Singh Rajendra , Metzger Dennis W.
Published: February 2007

Francisella tularensisis a gram-negative intracellular bacterium that is considered to be a potential category A biological weapon due to its extreme virulence. Although vaccination with the attenuated live vaccine strain (LVS) ofF. tularensiscan protect against lethal challenge, use of inactivated or subunit forms as vaccine candidates for induction of protective antibody responses has not been fully evaluated. In the present study, we examined whether immune protection in the lung could be stimulated by intranasal administration of inactivated LVS together with interleukin-12 (IL-12) as an adjuvant. LVS was inactivated by heat, paraformaldehyde treatment, or exposure to UV, and inactivation of the preparations was confirmed by assessing bacterial growth and the survival of mice after direct inoculation. We found that mucosal vaccination with inactivated LVS provided 90 to 100% protection in mice after lethal intranasal challenge with 104CFU of LVS, and this protection was dependent on inclusion of exogenous IL-12 during vaccine administration. Survival of vaccinated mice after live bacterial challenge was correlated with reduced bacterial burden, decreased pulmonary inflammation, increased serum antibody titers, and lower levels of gamma interferon (IFN-γ), tumor necrosis factor alpha, and IL-6 in the lungs, livers, and spleens. Whereas NK cells were primarily responsible for the production of IFN-γ in unvaccinated, challenged animals, vaccinated mice had increased levels of lung IFN-γ+CD4+T cells after challenge. Significantly, mice genetically deficient in immunoglobulin A (IgA) expression were unable to survive lethal challenge after vaccination. These results are the first results to demonstrate that IgA-mediated protection against lethal respiratory tularemia occurs after mucosal vaccination with inactivatedF. tularensisLVS.
Physiological Osmotic Induction of
Leptospira interrogans
Adhesion: LigA and LigB Bind Extracellular Matrix Proteins and Fibrinogen
Authors: Choy Henry A. , Kelley Melissa M. , Chen Tammy L. , Møller Annette K. , Matsunaga James , Haake David A.
Published: February 2007

Transmission of leptospirosis occurs through contact of mucous membranes and abraded skin with freshwater contaminated by pathogenic
Leptospira
spp. Exposure to physiological osmolarity induces leptospires to express high levels of the Lig surface proteins containing imperfect immunoglobulin-like repeats that are shared or differ between LigA and LigB. We report that osmotic induction of Lig is accompanied by 1.6- to 2.5-fold increases in leptospiral adhesion to immobilized extracellular matrix and plasma proteins, including collagens I and IV, laminin, and especially fibronectin and fibrinogen. Recombinant LigA-unique and LigB-unique repeat proteins bind to these same host ligands. We found that the avidity of LigB in binding fibronectin is comparable to that of the
Staphylococcus aureus
FnBPA D repeats. Both LigA- and LigB-unique repeats interact with the amino-terminal fibrin- and gelatin-binding domains of fibronectin, which are also recognized by fibronectin-binding proteins mediating the adhesion of other microbial pathogens. In contrast, repeats common to both LigA and LigB do not bind these host proteins, and nonrepeat sequences in the carboxy-terminal domain of LigB show only weak interaction with fibronectin and fibrinogen. A functional role for the binding activity of LigA and LigB is suggested by the ability of the recombinants to inhibit leptospiral adhesion to fibronectin by 28% and 21%, respectively. The binding of LigA and LigB to multiple ligands present in different tissues suggests that these adhesins may be involved in the initial colonization and dissemination stages of leptospirosis. The characterization of the Lig adhesin function should aid the design of Lig-based vaccines and serodiagnostic tests.
Nasal Immunization withBurkholderia multivoransOuter Membrane Proteins and the Mucosal Adjuvant Adamantylamide Dipeptide Confers Efficient Protection against Experimental Lung Infections withB. multivoransandB. cenocepacia
Authors: Bertot Gustavo M. , Restelli Marcela A. , Galanternik Laura , Aranibar Urey Rene C. , Valvano Miguel A. , Grinstein Saúl
Published: February 2007

Chronic lung infection by opportunistic pathogens, such asPseudomonas aeruginosaand members of theBurkholderia cepaciacomplex, is a major cause of morbidity and mortality in patients with cystic fibrosis. Outer membrane proteins (OMPs) of gram-negative bacteria are promising vaccine antigen candidates. In this study, we evaluated the immunogenicity, protection, and cross-protection conferred by intranasal vaccination of mice with OMPs fromB. multivoransplus the mucosal adjuvant adamantylamide dipeptide (AdDP). Robust mucosal and systemic immune responses were stimulated by vaccination of naive animals with OMPs fromB. multivoransandB. cenocepaciaplus AdDP. Using a mouse model of chronic pulmonary infection, we observed enhanced clearance ofB. multivoransfrom the lungs of vaccinated animals, which correlated with OMP-specific secretory immunoglobulin A responses. Furthermore, OMP-immunized mice showed rapid resolution of the pulmonary infection with virtually no lung pathology after bacterial challenge withB. multivorans. In addition, we demonstrated that administration ofB. multivoransOMP vaccine conferred protection againstB. cenocepaciachallenge in this mouse infection model, suggesting that OMPs provide cross-protection against theB. cepaciacomplex. Therefore, we concluded that mucosal immunity toB. multivoranselicited by intranasal vaccination with OMPs plus AdDP could prevent early steps of colonization and infection withB. multivoransand also ameliorate lung tissue damage, while eliciting cross-protection againstB. cenocepacia. These results support the notion that therapies leading to increased mucosal immunity in the airways may help patients with cystic fibrosis.
Immunization of Pigs To Prevent Disease in Humans: Construction and Protective Efficacy of a
Salmonella enterica
Serovar Typhimurium Live Negative-Marker Vaccine
Authors: Selke Martin , Meens Jochen , Springer Sven , Frank Ronald , Gerlach Gerald-F.
Published: February 2007

Zoonotic infections caused by
Salmonella enterica
serovar Typhimurium pose a constant threat to consumer health, with the pig being a particularly major source of multidrug-resistant isolates. Vaccination, as a promising approach to reduce colonization and shedding, has been scarcely used, as it interferes with current control programs relying on serology as a means of herd classification. In order to overcome this problem, we set out to develop a negative-marker vaccine allowing the differentiation of infected from vaccinated animals (DIVA). Applying an immunoproteomic approach with two-dimensional gel electrophoresis, Western blot, and quadrupole time-of-flight tandem mass spectrometry, we identified the OmpD protein as a suitable negative marker. Using allelic exchange, we generated an isogenic mutant of the licensed live vaccine strain Salmoporc and showed that virulence of Salmoporc and that of the mutant strain, SalmoporcΔ
ompD
, were indistinguishable in BALB/c mice. In a pig infection experiment including two oral immunizations with SalmoporcΔ
ompD
and challenge with a multiresistant
S. enterica
serovar Typhimurium DT104 clinical isolate, we confirmed the protective efficacy of SalmoporcΔ
ompD
in pigs, showing a significant reduction of both clinical symptoms and colonization of lymph nodes and intestinal tract. OmpD immunogenic epitopes were determined by peptide spot array analyses. Upon testing of several 9-mer peptides, each including an immunogenic epitope, one peptide (positions F
100
to Y
108
) that facilitated the detection of infected animals independent of their vaccination status (DIVA function) was identified. The approach described overcomes the problems currently limiting the use of bacterial live vaccines and holds considerable potential for future developments in the field.
Cryoglobulinaemic vasculitis: classification and clinical and therapeutic aspects
Authors: Braun Gerald S , Horster Sophia , Wagner Katrin S , Ihrler Stephan , Schmid Holger
Published: February 2007

Cryoglobulinaemia may cause cutaneous vasculitis and glomerulonephritis, potentially leading to end stage renal failure. An important proportion of cryoglobulinaemias are secondary to hepatitis C virus infection. Emerging antiviral treatment options offer a chance for causal therapy of these cases of cryoglobulinaemia. This review summarises the classification and clinical and therapeutic aspects of cryoglobulinaemic vasculitis and glomerulonephritis.
Media advocacy, tobacco control policy change and teen smoking in Florida
Authors: Niederdeppe Jeff , Farrelly Matthew C , Wenter Dana
Published: February 2007

Objective:To assess whether media advocacy activities implemented by the Florida Tobacco Control Program contributed to increased news coverage, policy changes and reductions in youth smoking.

Methods:A content analysis of news coverage appearing in Florida newspapers between 22 April 1998 and 31 December 2001 was conducted, and patterns of coverage before and after the implementation of media advocacy efforts to promote tobacco product placement ordinances were compared. Event history analysis was used to assess whether news coverage increased the probability of enacting these ordinances in 23 of 67 Florida counties and ordinary least square (OLS) regression was used to gauge the effect of these policies on changes in youth smoking prevalence.

Results:The volume of programme-related news coverage decreased after the onset of media advocacy efforts, but the ratio of coverage about Students Working Against Tobacco (the Florida Tobacco Control Program’s youth advocacy organisation) relative to other topics increased. News coverage contributed to the passage of tobacco product placement ordinances in Florida counties, but these ordinances did not lead to reduced youth smoking.

Conclusion:This study adds to the growing literature supporting the use of media advocacy as a tool to change health-related policies. However, results suggest caution in choosing policy goals that may or may not influence health behaviour.
Revising the machine smoking regime for cigarette emissions: implications for tobacco control policy
Authors: Hammond David , Wiebel Friedrich , Kozlowski Lynn T , Borland Ron , Cummings K Michael , O’Connor Richard J , McNeill Ann , Connolly Greg N , Arnott Deborah , Fong Geoffrey T
Published: February 2007

Background:The WHO Framework Convenion on Tobacco Control includes provisions for testing and regulating cigarette emissions. However, the current international standard for generating cigarette emissions—the ISO machine smoking regime—is widely acknowledged to be inappropriate for purposes of setting regulatory restrictions.

Objective:To review alternatives to the ISO machine smoking regime and the extent to which they: 1) Represent human smoking behaviour, 2) Reduce the potential for industry exploitation, particularly in the area of risk communication, and 3) Serve as suitable measures for product regulation.

Methods:Emissions data from 238 Canadian cigarette brands tested under the ISO and “Canadian Intense” machine smoking regimes.

Results:None of the alternative smoking regimes, including the Canadian Intense method, are more “representative” of human smoking behaviour and none provide better predictors of human exposure.

Conclusions:Given that alternatives such as the Canadian Intense regime are subject to the same fundamental limitations as the ISO regime, key questions need to be addressed before any smoking regime should be used to set regulatory limits on smoke emissions. In the meantime, regulators should remove quantitative emission values from cigarette packages and more work should be done on alternative machine smoking methods.
“The law was actually drafted by us but the Government is to be congratulated on its wise actions”: British American Tobacco and public policy in Kenya: Table 1
Authors: Patel Preeti , Collin Jeff , Gilmore Anna B
Published: February 2007

Background and objective:British American Tobacco (BAT) has historically enjoyed a monopoly position in Kenya. Analysis of recent tobacco control debates and a case study of BAT’s response to the emergence of competition in Kenya are used to explore the company’s ability to shape public policy and its treatment of tobacco farmers.

Design:Analysis of internal industry documents from BAT’s Guildford depository, other relevant data and interviews with key informants.

Results:BAT enjoys extensive high-level political connections in Kenya, including close relationships with successive Kenyan presidents. Such links seems to have been used to influence public policy. Health legislation has been diluted and delayed, and when a competitor emerged in the market, BAT used its contacts to have the government pass legislation drafted by BAT that compelled farmers to sell tobacco to BAT rather than to its competitor. BAT was already paying farmers less than any other African leaf-growing company, and the legislation entrenched poor pay and a quasi-feudal relationship. BAT’s public relation’s response to the threat of competition and the ministers’ public statements extolling the economic importance of tobacco growing suggest that BAT has manipulated tobacco farming as a political issue.

Conclusions:The extent of BAT’s influence over public policy is consistent with the observations that, despite ratifying the Framework Convention on Tobacco Control, progress in implementing tobacco control measures in Kenya has been limited. The benefits of tobacco farming seem to be deliberately exaggerated, and an analysis of its true cost benefits is urgently needed. Tobacco farmers must be protected against BAT’s predatory practices and fully informed about its activities to help them have an informed role in policy debates. As image, particularly around the importance of tobacco farming, seems key to BAT’s ability to influence policy, the truth about its treatment of farmers must be publicised.
A research agenda for assessing the potential contribution of genomic medicine to tobacco control
Authors: Hall Wayne D
Published: February 2007

This paper identifies research priorities in evaluating the ways in which “genomic medicine”—the use of genetic information to prevent and treat disease—may reduce tobacco-related harm by: (1) assisting more smokers to quit; (2) preventing non-smokers from beginning to smoke tobacco; and (3) reducing the harm caused by tobacco smoking. The method proposed to achieve the first aim is “pharmacogenetics”, the use of genetic information to optimise the selection of smoking-cessation programmes by screening smokers for polymorphisms that predict responses to different methods of smoking cessation. This method competes with the development of more effective forms of smoking cessation that involve vaccinating smokers against the effects of nicotine and using new pharmaceuticals (such as cannabinoid antagonists and nicotine agonists). The second and third aims are more speculative. They include: screening the population for genetic susceptibility to nicotine dependence and intervening (eg, by vaccinating children and adolescents against the effects of nicotine) to prevent smoking uptake, and screening the population for genetic susceptibility to tobacco-related diseases. A framework is described for future research on these policy options. This includes: epidemiological modelling and economic evaluation to specify the conditions under which these strategies are cost-effective; and social psychological research into the effect of providing genetic information on smokers’ preparedness to quit, and the general views of the public on tobacco smoking.
Economic effect of a smoke-free law in a tobacco-growing community: Table 1
Authors: Pyles Mark K , Mullineaux Donald J , Okoli Chizimuzo T C , Hahn Ellen J
Published: February 2007

Objective:To determine whether Lexington, Kentucky’s smoke-free law affected employment and business closures in restaurants and bars. On 27 April 2004, Lexington-Fayette County implemented a comprehensive ordinance prohibiting smoking in all public buildings, including bars and restaurants. Lexington is located in a major tobacco-growing state that has the highest smoking rate in the US and was the first Kentucky community to become smoke-free.

Design:A fixed-effects time series design to estimate the effect of the smoke-free law on employment and ordinary least squares to estimate the effect on business openings and closings.

Subjects and settings:All restaurants and bars in Lexington-Fayette County, Kentucky and the six contiguous counties.

Main outcome measures:ES-202 employment data from the Kentucky Workforce Cabinet; Business opening/closings data from the Lexington-Fayette County Health Department, Environmental Division.

Results:A positive and significant relationship was observed between the smoke-free legislation and restaurant employment, but no significant relationship was observed with bar employment. No relationship was observed between the law’s implementation and employment in contiguous counties nor between the smoke-free law and business openings or closures in alcohol-serving and or non-alcohol-serving businesses.

Conclusions:No important economic harm stemmed from the smoke-free legislation over the period studied, despite the fact that Lexington is located in a tobacco-producing state with higher-than-average smoking rates.
Five in a row—reactions of smokers to tobacco tax increases: population-based cross-sectional studies in Germany 2001–2006
Authors: Hanewinkel Reiner , Isensee Barbara
Published: February 2007

Objective:To assess reactions of smokers to five waves of tobacco tax increases in Germany.

Design:A 10-wave cross-sectional study, with assessments before and after the tax increases.

Setting:General population of Germany.

Participants and methods:10 representative samples from the general population with a total number of 27 608 people aged ⩾14 years, including 8548 smokers (31% of the total sample), were interviewed.

Outcome measures:Reflection on smoking behaviour, and smoking behaviour (quitting, reducing, switching to a cheaper brand or no change) before and after tobacco tax increases.

Results:Before the tax increases, one third to more than half of the smokers reflected on their smoking behaviour, 9.7–13.9% intended to quit, 23.4–34.7% intended to reduce smoking and 10.8–16.4% intended to switch to cheaper tobacco products, whereas 36.1–52.1% did not intend any change at all. After the tax increases, one fourth to more than one third reported to have reflected on their smoking behaviour, 4.0–7.9% quit smoking owing to the increase, 11.5–16.6% reduced consumption and 11.0–19.9% switched to cheaper products. Significant associations were found between the height of the price increase and the intentions and reactions of smokers.

Conclusions:Price increases lead to a substantial reflection on smoking and intended and realised behaviour changes such as reduced consumption and switching to cheaper tobacco products. These effects are more pronounced the more the price rises. Therefore, taxation policy will lead to quitting and reducing smoking. However, complementary measures should also be taken to prevent smokers switching to cheaper tobacco products, which would reduce the effectiveness of taxation policy.
Death at a discount: how the tobacco industry thwarted tobacco control policies in US military commissaries
Authors: Smith Elizabeth A , Blackman Viginia S , Malone Ruth E
Published: February 2007

Background:The US military is perhaps the only retailer consistently losing money on tobacco. Military stores (commissaries and exchanges) have long sold discount-priced cigarettes, while the Department of Defense (DoD) pays directly for tobacco-related healthcare costs of many current and former customers. Tobacco use also impairs short-term troop readiness.

Objective:To examine the long struggle to raise commissary tobacco prices and the tobacco industry’s role in this policy effort.

Methods:Analysis of internal tobacco industry documents, searches of government and military websites and newspaper databases, and interviews with key informants identified in the documents.

Results:Efforts to raise commissary tobacco prices began in the mid-1980s. Opposition quickly emerged. Some military officials viewed tobacco use as a “right” and low prices as a “benefit”. Others raised issues of authority, and some saw the change as threatening the stores. The tobacco industry successfully exploited complex relationships among the Congress, the DoD, commissaries, exchanges and private industry, obstructing change for over a decade. Leadership from the Secretary and Assistant Secretaries of Defense, presidential support and procedural manoeuvring finally resulted in a modest price increase in 1996, but even then, high-level military officials were apparently threatened with retaliation from pro-tobacco Congressmen.

Conclusions:The longstanding military tradition of cheap cigarettes persists because of the politics of the military sales system, the perception within the military of tobacco use as a right, and tobacco industry pressures. Against its own best interests, the US military still makes tobacco available to service members at prices below those in the civilian sector.
Tobacco-related disease mortality among men who switched from cigarettes to spit tobacco
Authors: Henley S Jane , Connell Cari J , Richter Patricia , Husten Corinne , Pechacek Terry , Calle Eugenia E , Thun Michael J
Published: February 2007

Background:Although several epidemiological studies have examined the mortality among users of spit tobacco, none have compared mortality of former cigarette smokers who substitute spit tobacco for cigarette smoking (“switchers”) and smokers who quit using tobacco entirely.

Methods:A cohort of 116 395 men were identified as switchers (n = 4443) or cigarette smokers who quit using tobacco entirely (n = 111 952) when enrolled in the ongoing US American Cancer Society Cancer Prevention Study II. From 1982 to 31 December 2002, 44 374 of these men died. The mortality hazard ratios (HR) of tobacco-related diseases, including lung cancer, coronary heart disease, stroke and chronic obstructive pulmonary disease, were estimated using Cox proportional hazards regression modelling adjusted for age and other demographic variables, as well as variables associated with smoking history, including number of years smoked, number of cigarettes smoked and age at quitting.

Results:After 20 years of follow-up, switchers had a higher rate of death from any cause (HR 1.08, 95% confidence interval (CI) 1.01 to 1.15), lung cancer (HR 1.46, 95% CI 1.24 to 1.73), coronary heart disease (HR 1.13, 95% CI 1.00 to 1.29) and stroke (HR 1.24, 95% CI 1.01 to 1.53) than those who quit using tobacco entirely.

Conclusion:The risks of dying from major tobacco-related diseases were higher among former cigarette smokers who switched to spit tobacco after they stopped smoking than among those who quit using tobacco entirely.
IMMOBILIZING HINGED POLYGONS
Authors: CHEONG JAE-SOOK , VAN DER STAPPEN A. FRANK , GOLDBERG KEN , OVERMARS MARK H. , RIMON ELON
Published: February 2007

The immobilization of non-rigid objects is a largely unaddressed subject. We explore the problem by studying the immobilization of a serial chain of polygons connected by rotational joints, or hinges, in a given placement with frictionless point contacts. We show that n + 2 such contacts along edge interiors or at concave vertices suffice to immobilize any serial chain of n ≠ 3 polygons without parallel edges; it remains open whether five contacts can immobilize three hinged polygons. At most n + 3 contacts suffice to immobilize a serial chain of n polygons when the polygons are allowed to have parallel edges. We also study a robust version of immobility, comparable to the classical notion of form closure, which is insensitive to perturbations. The robustness is achieved at the cost of a small increase in the number of contacts: [Formula: see text] and [Formula: see text] frictionless point contacts suffice for a chain of n hinged polygons without and with parallel edges respectively.
BARGAINING WITH COMMITMENT UNDER AN UNCERTAIN DEADLINE
Authors: CALABUIG VICENT , CUNYAT ANTONI , OLCINA GONZALO
Published: February 2007

We consider an infinite horizon bargaining game in which a deadline can arise with positive probability and where players possess an endogenous commitment device. We show that for any truncation of the game, the equilibrium agreement can only take place if the deadline arises within this finite horizon. Since the deadline is an uncertain event, the equilibrium exhibits agreements which are delayed with positive probability.
STRATEGIC EQUILIBRIA WITH PARTIALLY CONSUMABLE WITHHOLDINGS
Authors: MORENO-GARCÍA EMMA
Published: February 2007

In this paper, we consider a pure exchange economy with a finite number of agents who behave strategically on endowments. A notion of strategic equilibrium with partial disposability is defined and it is shown the existence of mixed strategies equilibria. Purification results on the strategic equilibrium are obtained by considering a Walrasian endowment game with incomplete information. Finally, we obtain an asymptotic result by replicating the economy.
AN ECONOMIC ANALYSIS OF FINANCIAL SUPPORT AFTER DIVORCE
Authors: KRAFT KORNELIUS , STEBLER PIA
Published: February 2007

This paper analyses whether the effect of compensation of former spouses after divorce has an impact on the probability of divorces occurring. In particular, it is assumed that the income difference after divorce is shared equally between former spouses, in line with rules in Germany. The reference situation within the marriage is, on the one hand, Nash-bargaining and, on the other, Becker-type altruistic sharing. It turns out that sharing increases the probability of divorce where there are no changes in labor supply. If labor supply is adjusted to the sharing rules after divorce, no general result is possible. If productivity is similar, the sharing rule will lead to less divorces than in the absence of such a regulation. However with large productivity differences separations are more probable in the case of income sharing compared to a situation without such a compensation. Labor supply adjustment in general reduces the number of divorces compared to the situation without labor supply adjustment.
A NODES-TOGGLING GAME WITH CONTROLLABLE STOPPING TIME
Authors: LEE KING TAK
Published: February 2007

We consider a two-person multi-stage game with a very sparse information structure. Two players in the blind alternately move a chip which toggles the colors of nodes located around a circle. The second player also controls and picks the stopping time which is unknown to the first player. We solve this game by showing the first player has a strategy which is uniformly optimal against the strategies of the second player.
BIDDER WELFARE IN AN AUCTION WITH A BUYOUT OPTION
Authors: MATHEWS TIMOTHY
Published: February 2007

A buyout option enhances an auction by allowing a bidder to purchase the item at a pre-specified price (instead of attempting to obtain the item by way of auction). A comparison is made between the ex ante welfare of bidders in an auction with a buyout option to a traditional auction with no such option. The impact on bidder welfare is shown to depend upon the distribution from which bidder valuations are drawn. In comparison to a traditional auction with no buyout option, when a buyout option is in place either: all bidders are weakly better off (in which case the option results in an ex ante Pareto improvement) or bidders with "relatively high valuations" are worse off.
ON THE CHACTERISTIC NUMBERS OF VOTING GAMES
Authors: MARTIN MATHIEU , MERLIN VINCENT
Published: February 2007

This paper deals with the non-emptiness of the stability set for any proper voting game. We present an upper bound on the number of alternatives which guarantees the non emptiness of this solution concept. We show that this bound is greater than or equal to the one given by Le Breton and Salles (1990) for quota games.
E-POINTS IN EXTENSIVE GAMES WITH COMPLETE INFORMATION
Authors: MARCHI EZIO
Published: February 2007

In this paper we characterize a general existence theorem concerning E-points for n-persons extensive games with complete information. We provide a sufficient and necessary condition for the existence of such E-points.
DYNAMIC ENTRY GAMES: THE CASE OF NATURAL DUOPOLY
Authors: LAHMANDI-AYED RIM
Published: February 2007

In the case of natural duopoly, we suggest a finitely repeated game between two incumbent firms and a potential entrant that limits the incumbent firms' power and compels them to approach economic efficiency. We prove that such a game admits a perfect subgame equilibrium along which the incumbent firms maintain with equal quantities while preventing entry. Moreover, the incumbents' strategies along this path converge to average cost pricing quantities as the number of periods goes to infinity.
THE PEDESTRIAN PRINCIPLE FOR DIFFERENTIAL GAMES
Authors: STOCKBRIDGE RICHARD H. , ZHENG ZIYU
Published: February 2007

A dynamic normal formulation for differential games is introduced and the "pedestrian principle" is discussed as a means of dynamically implementing the equilibrium strategy in a single game. Our formulation emphasizes the distinction between a player's rational prediction and the actual evolution of the game dynamics. To model the free will of players, a randomized strategy is introduced which serves as the justification of mixed strategies and the bridge from a static analysis to a dynamic one. Existence of Nash equilibrium in the class of mixed strategies is proved for non-cooperative deterministic differential games.
Application of head-flow responses to groundwater floods in Chalk catchments
Authors: Bradford R.B. , Croker K.M.
Published: February 2007

The application of head-flow (
hQ
) plots for fluvial groundwater flood alert systems is examined using synchronous values of groundwater heads and gauged river flows from instrumented, largely drift-free Chalk catchments in the Thames Valley and South Downs, UK. Three types of head-flow response are identified. These are correlated with the depth to water table. The rapid increase in groundwater discharge per unit rise in water level during periods of more extreme recharge is due to activation of the ephemeral drainage system and shallow zones of high permeability. Annual maximum
hQ
data tend to overestimate the threshold point at which a catchment becomes more responsive to further recharge. Flood alerts should employ a combination of both head and flow values based on plots of rising groundwater levels during wet winters from monitoring wells located within the ephemeral part of the drainage system.
Migration of polluted mine water in a public supply aquifer
Authors: Neymeyer A. , Williams R.T. , Younger P.L.
Published: February 2007

Following the cessation of dewatering in the southern part of the Durham Coalfield in 1974, groundwater levels rose in both the mine workings and the overlying Magnesian Limestone Aquifer (MLA). A pollution plume has since been migrating through the MLA, with sulphate concentrations greatly exceeding potable water standards. Prediction of future plume development requires specification of whether upflow of mine water to the MLA occurs from a small number of point sources or in a diffuse manner (i.e. distributed over most of the area in which the MLA is underlain by mineworkings). A programme of conceptual and numerical modelling has addressed this issue. Mine plans and geological information were used to characterize the flooded mine system and its interface with the MLA. Piezometric and meteorological data were used to constrain finite difference simulations of groundwater flow in the MLA. Flow velocity vectors derived from these flow simulations allowed modelling of plume migration by solution of the advection–dispersion equation. The results of these simulations illustrate that it is necessary to invoke both point and diffuse upflow to explain the observed patterns of pollutant migration to 2003. Predictive modelling of further plume migration indicates that sulphate concentrations are likely to rise to unacceptable levels in the most proximal public supply wells within the next two decades.
Assessment of standard research sand for laboratory testing
Authors: Takahashi A. , Jardine R.J.
Published: February 2007

tandard soils are used worldwide as reference materials with which new model or single element experiments may be performed, assessed and calibrated. The testing databases associated with these are valuable resources that are particularly important when developing new procedures. However, the finite extent and variability of all natural deposits creates the possibility that standard soils may vary, or become unavailable, over time. The Ham River Sand (HRS), from the Thames Valley in the UK has been researched continuously and comprehensively in a series of studies since the 1940s, leading to a large database that includes recent advanced hollow cylinder, stress path triaxial and dynamic testing. Fresh samples are now unavailable and the paper describes a study of alternative sampling sources within the Thames Valley. Microscopic visual inspections, index measurements, direct shear, high pressure oedometer, bender element and stress path triaxial test data are presented in the paper, focusing on the natural variability and the ranges seen in material test response. A replacement for the original HRS is identified, so allowing those developing new tests the possibility of conducting experiments on material that is compatible with the existing HRS database. Reference is also made to advances in bender element testing achieved as part of the study.
Two-dimensional simulation of underground seepage in a dangerous piping zone of the Jingjiang Great Levee, the middle reach of the Yangtze River
Authors: Yi C. , Wang B. , Jin M. , Guo Z.
Published: February 2007

This case study simulated the seepage field at Yangjiawan using Visual Modflow software. The Yangjiawan area shows potential for dangerous piping along the Jingjiang Great Levee, on the north bank of the Yangtze River. The levee foundation sits on loam and fine sand strata and is covered with a clay layer and artificial earthfill. Ponds are present behind the levee, where piping occurs frequently. The authors analysed several models to simulate actual situations and to provide guidance for piping control. Assuming that the potential for piping increases with seepage and groundwater velocities, the models allow various engineered control measures to be assessed under different natural conditions. Parameters and features of the models included: different water heads, pressure-relief wells, seepage-proof walls, surface coverage, different hydraulic conductivities of the artificial earthfill, and pond levels during high river water levels. The results demonstrate the effectiveness of pressure-relief wells in preventing piping and also show that a decrease of the hydraulic conductivities of the artificial earthfill would reduce infiltration and seepage damage significantly, especially during high river water levels. Furthermore, pressure-relief wells and the reduction of hydraulic conductivities of artificial earthfill should prevent piping if ponds are present.
Immune function in sport and exercise
Authors: Gleeson Michael
Published: February 2007

Regular moderate exercise is associated with a reduced incidence of infection compared with a completely sedentary state. However, prolonged bouts of strenuous exercise cause a temporary depression of various aspects of immune function (e.g., neutrophil respiratory burst, lymphocyte proliferation, monocyte antigen presentation) that usually lasts ∼3–24 h after exercise, depending on the intensity and duration of the exercise bout. Postexercise immune function dysfunction is most pronounced when the exercise is continuous, prolonged (>1.5 h), of moderate to high intensity (55–75% maximum O2 uptake), and performed without food intake. Periods of intensified training (overreaching) lasting 1 wk or more may result in longer lasting immune dysfunction. Although elite athletes are not clinically immune deficient, it is possible that the combined effects of small changes in several immune parameters may compromise resistance to common minor illnesses, such as upper respiratory tract infection. However, this may be a small price to pay as the anti-inflammatory effects of exercise mediated through cytokines and/or downregulation of toll-like receptor expression are likely mediators of many of the long-term health benefits of regular exercise.
Cone Inputs to Simple and Complex Cells in V1 of Awake Macaque
Authors: Horwitz Gregory D. , Chichilnisky E. J. , Albright Thomas D.
Published: February 2007

Rules by which V1 neurons combine signals originating in the cone photoreceptors are poorly understood. We measured cone inputs to V1 neurons in awake, fixating monkeys with white-noise analysis techniques that reveal properties of light responses not revealed by purely linear models used in previous studies. Simple cells were studied by spike-triggered averaging that is robust to static nonlinearities in spike generation. This analysis revealed, among heterogeneously tuned neurons, two relatively discrete categories: one with opponent L- and M-cone weights and another with nonopponent cone weights. Complex cells were studied by spike-triggered covariance, which identifies features in the stimulus sequence that trigger spikes in neurons with receptive fields containing multiple linear subunits that combine nonlinearly. All complex cells responded to nonopponent stimulus modulations. Although some complex cells responded to cone-opponent stimulus modulations too, none exhibited the pure opponent sensitivity observed in many simple cells. These results extend the findings on distinctions between simple and complex cell chromatic tuning observed in previous studies in anesthetized monkeys.