bluuebunny/crossref_metadata_2025 huggingface dataset:
Marketing's Influence Tactics in New Product Development: A Study of High Technology Firms in China
Authors: Atuahene–Gima Kwaku , Li Haiyang
Published: October 2003

It has been widely recognized that marketing's interaction with other functional departments (e.g., R&D) has significant impact on new product success. However, little research addresses how marketing actually behaves in the process of new product development (NPD). Drawing upon marketing, product innovation, and organizational buying literatures, this study contributes to the literature by delineating the types of influence tactics adopted by marketing and investigating how the use of these tactics affects marketing's influence on NPD decisions. Data on 128 new product projects from 114 high technology firms in China were collected from R&D perspective via on‐site interviews. The findings indicate that, from the R&D's perspective, both marketing and R&D seem to have equivalent influence on new product decisions. In terms of usage frequency, the most frequently used influence tactics by marketing are persistent pressure, information exchange, and recommendation (i.e., use of rational logic). Coalition formation (e.g., seeking the support of peers) and upward appeal (i.e., seeking support from superiors) tactics are moderately used. The less frequently used tactics are legalistic plea (i.e., use of rules and regulations) and request. Regarding the effectiveness of influence tactics, the results indicate that persistent pressure, information exchange, and coalition formation lead to higher marketing influence in NPD decisions. However, the use of an upward appeal tactic leads to lower marketing influence. Recommendation, legalistic plea and request tactics are unrelated to marketing's influence. Our results also show that the efficacy of marketing's influence tactics is contingent upon the degree of functional interdependence in the NPD stages and the degree of interdepartmental conflict. Information exchange and coalition formation tactics are more effective at the initiation stage of the NPD process whereas legalistic plea and persistent pressure are more effective at the implementation stage. We further find that legalistic plea is more effective but coalition tactic is less effective when the degree of interdepartmental conflict is higher. Findings of this study provide managers responsible for ensuring market‐oriented NPD with a better understanding of how the influence of marketing in the NPD process may be enhanced. Given our focus on Chinese firms, they also suggest that managers need to be sensitive to the cultural context of marketing influence.
Rent Controls in Ontario: Roofs or Ceilings?
Authors: Smith Lawrence B. , Tomlinson Peter
Published: October 2003

This paper describes the rent control program in Ontario and discusses the consequences of these controls. It indicates that rent controls caused both a small nominal decline and a large real decline in the per unit value of rental apartments, substantially reduced new rental housing starts, generated a rental housing shortage, created a dual market with significant rent differences between the controlled and uncontrolled (new construction) sectors, and imposed large costs on government in the form of foregone tax revenues and increased rental housing subsidies. The paper also indicates some of the political responses to the developing economic effects, such as the imposition of additional land use controls and increased government spending programs to stimulate new rental construction.
The Effects of Local Government Expenditure and Property Taxes on Investment*
Authors: Church Albert M.
Published: October 2003

The effect of local government property taxes and expenditures on investment in housing and manufacturing plant and equipment is analyzed in theoretic model and tested empirically. An investment model of firm behavior is developed and implications regarding the effects are deduced. These implications are tested in a single equation model of investment in single‐ and multifamily structures and capital investment in manufacturing in eleven urban cities and their eighty‐nine suburbs. Tentative conclusions that additional municipal expenditures increase investment and a higher effective property tax rate diminishes it are supported and that cities have on average exhausted the net benefits of increasing balanced budgets.
Commercial Real Estate Returns
Authors: Miles Mike , McCue Tom
Published: October 2003

In the commercial real estate market, which is perceived to be relatively inefficient, investors have comparative advantages; hence there are significant costs to diversification. This paper presents for the first time a series of market (or quasi‐market) returns for a large data base. This data base is believed to be the most complete commercial real estate data base yet constructed. The paper empirically evaluates the benefits of diversification along various dimensions within the commercial real estate opportunity set. The analysis confirms certain aspects of prior work concerning inflation protection and diversification opportunities while concluding that even investment grade real estate investments are heterogeneous assets.
Estimation of Mortgage Defaults Using Disaggregate Loan History Data
Authors: Vandell Kerry D. , Thibodeau Thomas
Published: October 2003

This paper addresses, theoretically and empirically, the structure of influences affecting the default option in mortgage contracts. A formal theoretical model recognizes that a number of loan and non‐loan related effects beyond equity in the unit could influence the default decision. These include 1) payment levels relative to income, which could displace other investment opportunities or cause a need for borrowing or sale to meet mortgage obligations; 2) current and expected neighborhood and housing market conditions, in particular the expected relative rate of appreciation of the unit and the relative cost of homeownership; 3) economic conditions; 4) wealth; 5) borrower characteristics proxying for variability in income or “crisis” events; as well as 6) transactions costs incurred upon default. Estimates of the model making use of a micro‐level sample of individual loan histories over a twelve year period, supplemented by longitudinal census and economic information, find a number of these “other” effects important. Simulations find several of them to dominate the equity effect on default and to help explain why some households with zero or negative equity may not default, while others with positive equity may. The implications of these results for appropriate specification of the pricing model describing the default option and for appropriate underwriting of AMIs are noted.
Has the United States Overinvested in Housing?
Authors: Mills Edwin S.
Published: October 2003

Several economists have concluded that housing investment has been excessive relative to industrial investment in the U.S. Most blame provisions of the federal income tax that favor owner‐occupied housing.

This paper poses the question within a two‐sector neoclassical growth model which permits the social return to housing to differ from that to non‐housing. The model is estimated using national income accounts and capital stock data from 1929 to 1983. The conclusion is that the return to housing capital is about half that to non‐housing capital and that the housing stock should be about 75% of its 1983 volume.
Explaining the Variability of Apartment Rents
Authors: Guntermann Karl L. , Norrbin Stefan
Published: October 2003

The research reported here uses regression analysis to analyze rent variations in a sample of apartment data from the Phoenix metropolitan area. Many of the variables used in hedonic price studies of houses are found to be significant in explaining variations in apartment rent. There are differences between hedonic studies of houses and apartments particularly with respect to common area features or amenities. The analysis of various submarkets also produced interesting results. Various uses can be made of the results of this and similar studies by appraisers (market‐derived adjustments), property managers (setting rents) and feasibility analysts (the design of apartment projects).
The Real Estate Brokerage Market: A Critical Reevaluation
Authors: Zumpano Leonard V. , Hooks Donald L.
Published: October 2003

This paper presents an analysis of the theories and evidence regarding the structure and performance of the market for real estate brokerage services. Some of the theoretical models found in the literature appear to suffer from logical inconsistencies, while others lack empirical support for their underlying assumptions and/or their predictions of market inefficiencies. Moreover, several important legal and institutional changes that have occurred recently have not been given sufficient attention in the existing literature.

Although some new evidence on this market is presented here, additional empirical research is warranted in at least two areas: the current pricing structure and the underlying production and cost functions of the real estate brokerage industry.
Information Costs and the Organization of the Real Estate Brokerage Industry in the U.S. and Great Britain
Authors: Miceli Thomas J.
Published: October 2003

This paper examines the differing organizations of the residential real estate brokerage industry in the U.S. and Great Britain, and argues that they may be interpreted as alternative solutions to a common set of informational problems. Of particular interest is why the multiple listing service — an arrangement whereby brokers share market information in an effort to exploit the public‐good nature of information — is so pervasive in the United States, but is largely absent in Great Britain. Some possible reasons are found in the differing histories of the parent housing markets, as well as other institutional differences.
Rental Housing Markets and the Natural Vacancy Rate
Authors: Gabriel Stuart A. , Nothaft Frank E.
Published: October 2003

This paper employs new census vacancy rate data to analyze the price‐adjustment mechanism for rental housing. The study extends previous research on this topic, which provided conflicting evidence concerning the traditional theory of rental housing market adjustment (see Smith [10], [11]; DeLeeuw and Ekanem [2]; Eubank and Sirmans [4]; and Rosen and Smith [8]). Cross‐section and time‐series data are pooled to estimate natural vacancy rates for sixteen United States cities for the 1981–85 period. The analysis further explores the determinants of variation in natural vacancy rates across those metropolitan areas.
Genomic Priorities and Public Health
Authors: Merikangas Kathleen Ries , Risch Neil
Published: October 2003

Given the continuing difficulty of identifying genes for complex disorders in a robust, replicable manner, and the extensive resources devoted to this effort, it is becoming increasingly important to analyze the relative benefits of genomics research for public health applications and for the understanding of disease pathogenesis. To establish priorities for genetics research, we review and evaluate several characteristics of selected exemplary complex diseases, including phenotypic accuracy, knowledge of specific and nonspecific genetic and environmental risk factors, and population prevalence and impact. We propose that complex diseases with the strongest evidence for genetic etiology, limited ability to modify exposure or risk factors, and high public health impact should have the highest priority for genetics research.
Heterogeneity of Macrolide-Lincosamide-Streptogramin B Resistance Phenotypes in Enterococci
Authors: Min Yu-Hong , Jeong Jae-Hee , Choi Yun-Jeong , Yun Hee-Jeong , Lee Kyungwon , Shim Mi-Ja , Kwak Jin-Hwan , Choi Eung-Chil
Published: October 2003

We determined the macrolide resistance phenotypes of 241 clinical isolates of erythromycin-resistant enterococci (MICs, ≥1 μg/ml), including 147
Enterococcus faecalis
strains and 94
Enterococcus faecium
strains, collected from a hospital in Seoul, Korea, between 1999 and 2000. By the erythromycin (40 μg)-josamycin (100 μg) double-disk test, 93 strains were assigned to the constitutive macrolide, lincosamide, and streptogramin B (MLS
B
) resistance (cMLS
B
) phenotype, and the remaining 148 strains were assigned to the inducible MLS
B
resistance (iMLS
B
) phenotype. Of the strains with the iMLS
B
phenotype, 36 exhibited a reversibly inducible MLS
B
(riMLS
B
) phenotype, i.e., blunting of the erythromycin zone of inhibition, which indicates that the 16-membered-ring macrolide josamycin is a more effective inducer than the 14-membered-ring macrolide erythromycin. Sequence analysis of the regulatory regions of the
erm
(B) genes from all of the strains exhibiting the riMLS
B
phenotype revealed not only
erm
(Bv) [where v represents variant; previously
erm
(AMR)] (
n
= 13), as reported previously, but also three kinds of
erm
(B) variants, which were designated
erm
(Bv1) (
n
= 17),
erm
(Bv2) (
n
= 3), and
erm
(Bv3) (
n
= 3), respectively. In
lacZ
reporter gene assays of these variants, the 16-membered-ring macrolide tylosin had stronger inducibility than erythromycin at ≥0.1 μg/ml. These findings highlight the versatility of
erm
(B) in induction specificity.
Cefepime versus Imipenem-Cilastatin for Treatment of Nosocomial Pneumonia in Intensive Care Unit Patients: a Multicenter, Evaluator-Blind, Prospective, Randomized Study
Authors: Zanetti G. , Bally F. , Greub G. , Garbino J. , Kinge T. , Lew D. , Romand J.-A. , Bille J. , Aymon D. , Stratchounski L. , Krawczyk L. , Rubinstein E. , Schaller M.-D. , Chiolero R. , Glauser M.-P. , Cometta A. ,   the Cefepime Study Group
Published: October 2003

In a randomized, evaluator-blind, multicenter trial, we compared cefepime (2 g three times a day) with imipenem-cilastatin (500 mg four times a day) for the treatment of nosocomial pneumonia in 281 intensive care unit patients from 13 centers in six European countries. Of 209 patients eligible for per-protocol analysis of efficacy, favorable clinical responses were achieved in 76 of 108 (70%) patients treated with cefepime and 75 of 101 (74%) patients treated with imipenem-cilastatin. The 95% confidence interval (CI) for the difference between these response rates (−16 to 8%) failed to exclude the predefined lower limit for noninferiority of −15%. In addition, therapy of pneumonia caused by an organism producing an extended-spectrum β-lactamase (ESBL) failed in 4 of 13 patients in the cefepime group but in none of 10 patients in the imipenem group. However, the clinical efficacies of both treatments appeared to be similar in a secondary intent-to-treat analysis (95% CI for difference, −9 to 14%) and a multivariate analysis (95% CI for odds ratio, 0.47 to 1.75). Furthermore, the all-cause 30-day mortality rates were 28 of 108 (26%) patients in the cefepime group and 19 of 101 (19%) patients in the imipenem group (
P
= 0.25). Rates of documented or presumed microbiological eradication of the causative organism were similar with cefepime (61%) and imipenem-cilastatin (54%) (95% CI, −23 to 8%). Primary or secondary resistance of
Pseudomonas aeruginosa
was detected in 19% of the patients treated with cefepime and 44% of the patients treated with imipenem-cilastatin (
P
= 0.05). Adverse events were reported in 71 of 138 (51%) and 62 of 141 (44%) patients eligible for safety analysis in the cefepime and imipenem groups, respectively (
P
= 0.23). Although the primary end point for this study does not exclude the possibility that cefepime was inferior to imipenem, some secondary analyses showed that the two regimens had comparable clinical and microbiological efficacies. Cefepime appeared to be less active against organisms producing an ESBL, but primary and secondary resistance to imipenem was more common for
P. aeruginosa
. Selection of a single agent for therapy of nosocomial pneumonia should be guided by local resistance patterns.
Effect of Parenteral Antibiotic Administration on Establishment of Intestinal Colonization in Mice by
Klebsiella pneumoniae
Strains Producing Extended-Spectrum β-Lactamases
Authors: Hoyen Claudia K. , Pultz Nicole J. , Paterson David L. , Aron David C. , Donskey Curtis J.
Published: October 2003

A mouse model was used to test the hypothesis that antibiotics with activity against anaerobes promote overgrowth of extended-spectrum β-lactamase-producing
Klebsiella pneumoniae
strains in stool. Subcutaneous clindamycin consistently promoted establishment of high-density colonization, whereas piperacillin-tazobactam, ceftriaxone, and ceftazidime promoted colonization only when a large inoculum and/or more resistant strain was administered.
Activity of AZD2563, a Novel Oxazolidinone, against
Staphylococcus aureus
Strains with Reduced Susceptibility to Vancomycin or Linezolid
Authors: Howe Robin A. , Wootton Mandy , Noel Alan R. , Bowker Karen E. , Walsh Timothy R. , MacGowan Alasdair P.
Published: October 2003

The susceptibilities of clinical vancomycin-intermediate
Staphylococcus aureus
(VISA), heterogenous VISA, and laboratory-generated linezolid-resistant
S. aureus
strains to the new oxazolidinone AZD2563 were assessed by agar dilution MIC determination. All clinical strains were susceptible to linezolid, and the linezolid MICs for them were equal to or twofold higher than those of AZD2563. Cross-resistance with linezolid was seen in laboratory-generated mutants, and for these strains the MIC of AZD2563 was twofold higher than that of linezolid.
The Streptococcal Exotoxin Streptolysin O Activates Mast Cells To Produce Tumor Necrosis Factor Alpha by p38 Mitogen-Activated Protein Kinase- and Protein Kinase C-Dependent Pathways
Authors: Stassen Michael , Müller Christian , Richter Christoph , Neudörfl Christine , Hültner Lothar , Bhakdi Sucharit , Walev Iwan , Schmitt Edgar
Published: October 2003

Streptolysin O (SLO), a major virulence factor of pyogenic streptococci, binds to cholesterol in the membranes of eukaryotic cells and oligomerizes to form large transmembrane pores. While high toxin doses are rapidly cytocidal, low doses are tolerated because a limited number of lesions can be resealed. Here, we report that at sublethal doses, SLO activates primary murine bone marrow-derived mast cells to degranulate and to rapidly induce or enhance the production of several cytokine mRNAs, including tumor necrosis factor alpha (TNF-α). Mast cell-derived TNF-α plays an important protective role in murine models of acute inflammation, and the production of this cytokine was analyzed in more detail. Release of biologically active TNF-α peaked ∼4 h after stimulation with SLO. Production of TNF-α was blunted upon depletion of protein kinase C by pretreatment of the cells with phorbol-12 myristate-13 acetate. Transient permeabilization of mast cells with SLO also led to the activation of the stress-activated protein kinases p38 mitogen-activated protein (MAP) kinase and c-jun N-terminal kinase (JNK), and inhibition of p38 MAP kinase markedly reduced production of TNF-α. In contrast, secretion of preformed granule constituents triggered by membrane permeabilization was not dependent on p38 MAP kinase or on protein kinase C. Thus, transcriptional activation of mast cells following transient permeabilization might contribute to host defense against infections via the beneficial effects of TNF-α. However, hyperstimulation of mast cells might also lead to overproduction of TNF-α, which would then promote the development of toxic streptococcal syndromes.
Infection byTrypanosoma cruziMetacyclic Forms Deficient in gp82 but Expressing a Related Surface Molecule, gp30
Authors: Cortez Mauro , Neira Ivan , Ferreira Daniele , Luquetti Alejandro O. , Rassi Anis , Atayde Vanessa D. , Yoshida Nobuko
Published: October 2003

Trypanosoma cruzimetacyclic trypomastigotes invade and replicate in the gastric mucosal epithelium after oral infection. In this study we analyzed the process of infection byT. cruziisolates deficient in the expression of gp82, the metacyclic stage-specific surface glycoprotein implicated in target cell entry in vitro and in promoting mucosal infection in mice after oral challenge. Mice infected by the oral route with metacyclic forms of gp82-deficient isolate 569 or 588 developed patent parasitemia but at greatly reduced levels compared to those infected with the gp82-expressing isolate CL. Metacyclic forms of both isolates expressed gp30, a surface glycoprotein detectable by monoclonal antibody (MAb) 3F6 directed to gp82. Otherwise, the gp82-deficient isolates displayed a surface profile similar to that of the CL isolate and also entered epithelial HeLa cells in a manner inhibitable by MAb 3F6 and dependent on the parasite signal transduction that involved the activation of protein tyrosine kinase and Ca2+mobilization from thapsigargin-sensitive stores. Like gp82, gp30 triggered the host cell Ca2+response required for parasite internalization. Purified gp30 and the recombinant gp82 inhibited HeLa cell invasion of metacyclic forms of isolates 569 and 588 by ∼90 and ∼70%, respectively. A cell invasion assay performed in the presence of gastric mucin, mimicking the in vivo infection, showed an inhibition of 70 to 75% in the internalization of gp82-deficient isolates but not of the CL isolate. The recombinant gp82 exhibited an adhesive capacity toward gastric mucin much higher than that of gp30. Taken together, our findings indicate that target cell entry of metacyclic trypomastigotes can be mediated either by gp82 or gp30 but that efficient mucosal infection depends on the expression of gp82.
Comparison of Two Major Forms of the
Shigella
Virulence Plasmid pINV: Positive Selection Is a Major Force Driving the Divergence
Authors: Lan Ruiting , Stevenson Gordon , Reeves Peter R.
Published: October 2003

All
Shigella
and enteroinvasive
Escherichia coli
(EIEC) strains carry a 230-kb virulence plasmid (pINV) which is essential for their invasiveness. There are two sequence forms, pINV A and pINV B, of the plasmid (R. Lan, B. Lumb, D. Ryan, and P. R. Reeves, Infect. Immun. 69:6303-6309, 2001), and the recently sequenced pINV plasmid from
Shigella flexneri
serotype 5 is a pINV B form. In this study we sequenced the majority of the coding region of the pINV A form from
S
.
flexneri
serotype 6 other than insertion sequence or related sequences and compared it with the pINV B form. More than half of the genes sequenced appear to be under positive selection based on their low ratio of synonymous to nonsynonymous substitutions. This high proportion of selected differences indicates that the two pINV forms have functional differences, and comparative studies of pathogenicity in different
Shigella
-EIEC strains could be informative. There are also genes absent in the
S
.
flexneri
serotype 6 plasmid, including the
sepA
gene encoding serine protease, the major secreted protein of
S
.
flexneri
serotype 2a, and the
stbAB
genes, which encode one of the two partition systems found in
S
.
flexneri
serotype 5. The incompatibility of the two pINV forms appears to be due to either small differences in the
mvpAT
postsegregational killing system or the presence of an unknown system in pINVA.
Plasma Interleukin-12 in Malaria-Tolerant Papua New Guineans: Inverse Correlation withPlasmodium falciparumParasitemia and Peripheral Blood Mononuclear Cell Nitric Oxide Synthase Activity
Authors: Boutlis Craig S. , Lagog Moses , Chaisavaneeyakorn Sujittra , Misukonis Mary A. , Bockarie Moses J. , Mgone Charles S. , Wang Zhiqiang , Morahan Grant , Weinberg J. Brice , Udhayakumar Venkatachalam , Anstey Nicholas M.
Published: October 2003

Interleukin-12 (IL-12) has been inversely associated with disease severity in human and murine malaria, and a polymorphism in the IL-12 p40 subunit gene (IL12B) has been associated with susceptibility to human cerebral malaria and reduced nitric oxide (NO) production. To better define the relationships between IL-12, NO, malaria parasitemia, andIL12Bpolymorphisms during malarial tolerance, plasma IL-12 levels and peripheral blood mononuclear cell NO synthase (NOS) activity were measured in asymptomatic Papua New Guineans exposed to intense malaria transmission. The IL-12 level was strongly inversely correlated with the density ofPlasmodium falciparumparasitemia (ρ = −0.45;P< 0.001) and was predicted to decrease by 19% (95% confidence interval [CI], 10 to 27%) for each twofold increase inP. falciparumparasitemia. This is consistent with a suppressive effect of parasitemia on IL-12 production, an effect previously shown in vitro and in rodent models of disease. The IL-12 level was inversely correlated with NOS activity (r= −0.22;P= 0.007), with each twofold increase in NOS activity being predictive of a 25% (95% CI, 7 to 38%) decrease in plasma IL-12 levels. This probably reflects additional down-regulation of IL-12 by the high basal NO production and monocyte NOS expression found in the malaria-tolerant state. Neither the IL-12 level nor NOS activity was associated with either of twoIL12Bpolymorphisms, reflecting the diversity of genetic control over immune responses in different populations.
DNA Vaccination Protects Mice against Challenge withListeria monocytogenesExpressing the Hepatitis C Virus NS3 Protein
Authors: Simon Benjamin E. , Cornell Kenneth A. , Clark Tina R. , Chou Sunwen , Rosen Hugo R. , Barry Ronald A.
Published: October 2003

The goal of this study was to develop a new surrogate challenge model for use in evaluating protective cell-mediated immune responses against hepatitis C virus (HCV) antigens. The use of recombinantListeria monocytogenesorganisms which express HCV antigens provides novel tools with which to assay such in vivo protection, as expression of immunity against this hepatotropic bacterial pathogen is dependent on antigen-specific CD8+T lymphocytes. A plasmid DNA vaccine encoding a ubiquitin-NS3 fusion protein was generated, and its efficacy was confirmed by in vivo induction of NS3-specific, gamma interferon-secreting T cells following vaccination of BALB/c mice. These immunized mice also exhibited specific in vivo protection against subsequent challenge with a recombinantL. monocytogenesstrain (TC-LNS3) expressing the NS3 protein. Notably, sublethal infection of naive mice with strain TC-LNS3 induced similar NS3-specific T-cell responses. These findings suggest that recombinant strains ofL. monocytogenesexpressing HCV antigens should prove useful for evaluating, or even inducing, protective immune responses against HCV antigens.
RecombinantLeishmania majorSecreting Biologically Active Granulocyte-Macrophage Colony-Stimulating Factor Survives Poorly in Macrophages In Vitro and Delays Disease Development in Mice
Authors: Dumas Carole , Muyombwe Anthony , Roy Gaétan , Matte Claudine , Ouellette Marc , Olivier Martin , Papadopoulou Barbara
Published: October 2003

Leishmaniais an intracellular pathogen that replicates inside macrophages. Activated macrophages produce a specific subset of cytokines that play an important role in the control ofLeishmaniainfections. As part of our interest in developing suicide parasites that produce abortive infections for the purposes of vaccination, we engineered recombinantLeishmania majorstrains producing biologically active granulocyte-macrophage colony-stimulating factor (GM-CSF). We showed that GM-CSF is being produced in the phagosomes of infected macrophages and that it can be detected in the culture supernatants of both infected macrophages and extracellular parasites. Our data support the notion that GM-CSF secreted by both developmental forms of recombinantL. majorcan activate macrophages to produce high levels of proinflammatory cytokines such as interleukin-1β (IL-1β), IL-6, and IL-18 and various chemokines including RANTES/CCL5, MIP-1α/CCL3, MIP-1β/CCL4, MIP-2/CXCL2, and MCP-1/CCL2, which enhance parasite killing. Indeed, GM-CSF-expressing parasites survive poorly in macrophages in vitro and produce delayed lesion development in susceptible BALB/c mice in vivo. Selective killing of intracellularLeishmaniaexpressing cytokine genes capable of activating cellular responses may constitute a promising strategy to control and/or prevent parasitic infections.
Vaccination withToxoplasma gondiiSAG-1 Protein Is Protective against Congenital Toxoplasmosis in BALB/c Mice but Not in CBA/J Mice
Authors: Letscher-Bru Valerie , Pfaff Alexander W. , Abou-Bacar Ahmed , Filisetti Denis , Antoni Elisabeth , Villard Odile , Klein Jean-Paul , Candolfi Ermanno
Published: October 2003

We evaluated the effect of vaccination with the SAG1 protein ofToxoplasma gondiiagainst congenital toxoplasmosis in mice with different genetic backgrounds. In BALB/c mice (H-2d), vaccination reduced the number of infected fetuses by 50% and was associated with a mixed type 1 and type 2 immunity. In CBA/J mice (H-2k), vaccination increased the number of infected fetuses by 50% and was associated with a predominant type 2 response. Our results indicate that the effect of vaccination with SAG1 is controlled by the genetic background of the mouse.
Toll-Like Receptor Expression in C3H/HeN and C3H/HeJ Mice duringSalmonella entericaSerovar Typhimurium Infection
Authors: Tötemeyer Sabine , Foster Neil , Kaiser Pete , Maskell Duncan J. , Bryant Clare E.
Published: October 2003

Here, we have investigated the mRNA expression of Toll-like receptor 2 (TLR-2), TLR-4, and MD-2 in spleens and livers of C3H/HeN mice (carrying wild-type TLR-4) and C3H/HeJ mice (carrying mutated TLR-4) in response toSalmonellainfection. DuringSalmonellainfections, TLR-4 is activated, leading to increased TLR-2 and decreased TLR-4 expression.
The MicAB Two-Component Signaling System Is Involved in Virulence of
Streptococcus pneumoniae
Authors: Kadioglu Aras , Echenique Josè , Manco Sonia , Trombe Marie-Claude , Andrew Peter W.
Published: October 2003

In
Streptococcus pneumoniae
, the two-component signaling system MicAB was previously shown to contribute to repression of competence when oxygen is limited. In virulent strains expressing the serotype 2 and 6 capsule, mutation of the MicB kinase reduced the lag period of growth when cultures were switched from an aerobic to anaerobic atmosphere. After intranasal challenge of mice, the
micB
::
km
mutation decreased virulence, as shown by the absence of symptoms and by a lower level of recovery of CFU from lungs and blood. It is proposed that MicAB is involved in the adaptive response of the bacteria to changes in oxygen level during the course of infection.
Putative Interhelical Interactions within the PheP Protein Revealed by Second-Site Suppressor Analysis
Authors: Dogovski C. , Pi J. , Pittard A. J.
Published: October 2003

Highly conserved glycine residues within span I and span II of the phenylalanine and tyrosine transporter PheP were shown to be important for the function of the wild-type protein. Replacement by amino acids with increasing side chain volume led to progressive loss of transport activity. Second-site suppression studies performed with a number of the primary mutants revealed a tight packing arrangement between spans I and II that is important for function and an additional interaction between spans I and III. We also postulate that a third motif, GXXIG, present in span I and highly conserved within different members of the amino acid-polyamine-organocation family, may function as a dimerization motif. Surprisingly, other highly conserved residues, such as Y60 and L41, could be replaced by various residues with no apparent loss of activity.
Involvement of an Inducible Fructose Phosphotransferase Operon in
Streptococcus gordonii
Biofilm Formation
Authors: Loo C. Y. , Mitrakul K. , Voss I. B. , Hughes C. V. , Ganeshkumar N.
Published: October 2003

Oral streptococci, such as
Streptococcus gordonii
, are the predominant early colonizers that initiate biofilm formation on tooth surfaces. Investigation of an
S. gordonii
::Tn
917-lac
biofilm-defective mutant isolated by using an in vitro biofilm formation assay showed that the transposon insertion is near the 3′ end of an open reading frame (ORF) encoding a protein homologous to
Streptococcus mutans
FruK. Three genes,
fruR
,
fruK
, and
fruI
, were predicted to encode polypeptides that are part of the fructose phosphotransferase system (PTS) in
S. gordonii
. These proteins, FruR, FruK, and FruI, are homologous to proteins encoded by the inducible
fruRKI
operon of
S. mutans
. In
S. mutans
, FruR is a transcriptional repressor, FruK is a fructose-1-phosphate kinase, and FruI is the fructose-specific enzyme II (fructose permease) of the phosphoenolpyruvate-dependent sugar PTS. Reverse transcription-PCR confirmed that
fruR
,
fruK
, and
fruI
are cotranscribed as an operon in
S. gordonii
, and the transposon insertion in
S. gordonii fruK
::Tn
917-lac
resulted in a nonpolar mutation. Nonpolar inactivation of either
fruK
or
fruI
generated by allelic replacement resulted in a biofilm-defective phenotype, whereas a nonpolar mutant with an inactivated
fruR
gene retained the ability to form a biofilm. Expression of
fruK
, as measured by the β-galactosidase activity of the
fruK
::Tn
917-lac
mutant, was observed to be growth phase dependent and was enhanced when the mutant was grown in media with high levels of fructose, sucrose, xylitol, and human serum, indicating that the fructose PTS operon was fructose and xylitol inducible, similar to the
S. mutans
fructose PTS. The induction by fructose was inhibited by the presence of glucose, indicating that glucose is able to catabolite repress
fruK
expression. Nonpolar inactivation of the
fruR
gene in the
fruK
::Tn
917-lac
mutant resulted in a greater increase in β-galactosidase activity when the organism was grown in media supplemented with fructose, confirming that
fruR
is a transcriptional repressor of the fructose PTS operon. These results suggest that the regulation of fructose transport and metabolism in
S. gordonii
is intricately tied to carbon catabolite control and the ability to form biofilms. Carbon catabolite control, which modulates carbon flux in response to environmental nutritional levels, appears to be important in the regulation of bacterial biofilms.
The IS
1111
Family Members IS
4321
and IS
5075
Have Subterminal Inverted Repeats and Target the Terminal Inverted Repeats of Tn
21
Family Transposons
Authors: Partridge Sally R. , Hall Ruth M.
Published: October 2003

IS
5075
and IS
4321
are closely related (93.1% identical) members of the IS
1111
family that target a specific position in the 38-bp terminal inverted repeats of Tn
21
family transposons and that are inserted in only one orientation. They are 1,327 bp long and have identical ends consisting of short inverted repeats of 12 bp with an additional 7 bp (TAATGAG) or 6 bp (AATGAG) to the left of the left inverted repeats and 3 bp (AGA) or 4 bp (AGAT) to the right of the right inverted repeat. Circular forms of IS
5075
and IS
4321
in which the inverted repeats are separated by abutting terminal sequences (AGATAATGAG) were detected. A similar circular product was found for the related ISPa11. Transposition of IS
4321
into the 38-bp target site was detected, but a flanking duplication was not generated. The precisely reconstituted target site was also identified. Over 50 members of the IS
1111
family were identified. They encode related transposases, have related inverted repeats, and include related bases that lie outside these inverted repeats. In some, the flanking bases number 5 or 6 on the left and 4 or 3 on the right. Specific target sites were found for several of these insertion sequence (IS) elements. IS
1111
family members therefore differ from the majority of IS elements, which are characterized by terminal inverted repeats and a target site duplication, and from members of the related IS
110
family, which do not have obvious inverted repeats near their termini.
Accuracy of the Lattice-Boltzmann Method
Authors: Maier Robert S. , Bernard Robert S.
Published: October 2003

The accuracy of the lattice-Boltzmann method (LBM) is moderated by several factors, including Mach number, spatial resolution, boundary conditions, and the lattice mean free path. Results obtained with 3D lattices suggest that the accuracy of certain two-dimensional (2D) flows, such as Poiseuille and Couette flow, persist even when the mean free path between collisions is large, but that of the 3D duct flow deteriorates markedly when the mean free path exceeds the lattice spacing. Accuracy in general decreases with Knudsen number and Mach number, and the product of these two quantities is a useful index for the applicability of LBM to 3D low-Reynolds-number flow. The influence of boundary representations on LBM accuracy is captured by the proposed index, when the accuracy of the prescribed boundary conditions is consistent with that of LBM.
Lattice-BGK Methods for Simulating Incompressible Fluid Flows
Authors: Chen Yu , Ohashi Hirotada
Published: October 2003

The lattice-Bhatnagar-Gross-Krook (BGK) method has been used to simulate fluid flow in the nearly incompressible limit. But for the completely incompressible flows, two special approaches should be applied to the general model, for the steady and unsteady cases, respectively. Introduced by Zou et al.,1 the method for steady incompressible flows will be described briefly in this paper. For the unsteady case, we will show, using a simple numerical example, the need to solve a Poisson equation for pressure.
Non-Spheric Colloidal Suspensions in Three-Dimensional Space
Authors: Qi Dewei
Published: October 2003

The translation and rotation of non-spherical particles, such as ellipsoidal, cylindric or disk-like pigment particles, in a Couette flow system similar to a blade coating system in the paper industry6 have been successfully simulated by using the lattice-Boltzmann method combined with Newtonian dynamic simulations. Hydrodynamic forces and torques are obtained by the use of boundary conditions which match the moving surface of solid particles. Then Euler equations have been integrated to include three-dimensional rotations of the suspensions by using four quaternion parameters as generalized coordinates. The three-dimensional rotations have been clearly observed. Consequently, the motion of the particles suspended in fluids of both low-Reynolds-number and finite-Reynolds-number, up to several hundreds, has been studied. It appears that the 3D translation and rotation of the non-spherical particles are more clearly observed in a high-Reynolds-number fluid than in a low-Reynolds-number fluid.
Relativistic Mean-Field Theory and the Structural Properties of Ne, Mg, Si, S, Ar and Ca Nuclei from Proton- to Neutron-Drip Lines
Authors: Patra S. K. , Gupta Raj K. , Greiner W.
Published: October 2003

We have investigated the gross structural properties of Ne, Mg, Si, S, Ar and Ca nuclei, starting from the proton-drip line till the neutron drip-line. An axially deformed self-consistent relativistic mean-field approach is used. All possible shapes (prolate, oblate or spherical) are searched, using three sets of force parameter, the NL2, NL-SH and TM2. Agreement between the calculation and experiment is found to be good, particularly for the TM2 force parameters. We find a sizeable deformation of the neutron/proton-rich Ne and Mg isotopes near the drip lines. Also, deformations of nuclei at and near the spherical magic shell N=28 are found to be large, in agreement with experiments. The breaking/non-breaking of the spherical shell gap at N=28 is also observed, dependent on the choice of force parameters and pairing strength. A large number of cases of shape coexistence are identified. The effects of pairing strength on the calculated properties are also discussed.
Cohabitation with a Sick Cage Mate: Consequences on Behavior and on Ehrlich Tumor Growth
Authors: Morgulis Maria Sílvia F.A. , Stankevicius Daniel , Sá-Rocha Luiz Carlos , Palermo-Neto João
Published: October 2003

The present study analyzed the effects of cohabitation for 11 days with a sick cage mate on behavior and Ehrlich tumor growth in mice. Pairs of female mice were divided into one control and one experimental group. One mouse of each control pair was kept undisturbed and called ‘healthy companion’ (HC). One animal of each experimental pair of mice was inoculated (i.p.) with 5 × 106 Ehrlich tumor cells, and the other, the object of this study, was called ‘sick companion’ (SC). The SC mice presented: (1) increased activity in an open field, (2) increased number of entries and of movements within the plus-maze open arms, (3) similar levels of plus-maze closed-arm exploration, (4) a decrease in the exploratory activity in a hole board, (5) a decrease in the number of white but not red blood cells, and (6) similar corticosterone serum levels. Eleven days after cohabitation with a conspecific, HC and SC mice were injected with 5 ×106 Ehrlich tumor cells. Results showed that SC animals presented decreased resistance to the ascitic form of the Ehrlich tumor. The observed data provide experimental evidence that psychosocial stress induced by cohabitation with a sick cage mate changed at the same time some behavioral and physiological parameters, and decreased resistance to Ehrlich tumor. These data are discussed in the light of a possible neuroimmune system interaction.
Reproductive Risk Factors Related to Socioeconomic Status in Pregnant Women in Southern Brazil
Authors: Momino Wakana , Minussi Lenice , Woffchuck Daniela , Palmero Edenir I. , Sanseverino Maria Teresa , Guimarães Fachel Jandyra Maria , Schüler-Faccini Lavínia
Published: October 2003

To evaluate patterns of drug use during pregnancy and other potential reproductive risks in pregnant women, we applied a standard questionnaire to 412 pregnant women classified as low socioeconomic status (SES) or as middle/high SES, in two cities of South Brazil. 77% of the women used at least one medication during pregnancy. We observed significant differences, when comparing low SES and middle/high SES groups, for the following variables: teenage pregnancies (28.4 vs. 12.4%); self-medication (21.8 vs. 13.1%); smoking habits (21.5 vs. 5.1%); unplanned pregnancies (69.5 vs. 51.8%); unwanted pregnancies (31.3 vs. 10.9%), and abortion attempts (13.1 vs. 5.8%). The average number of drugs consumed, however, was not different between low SES and middle/high SES. We believe that better education and conditions for family planning are key points to improve this scenario.
Knowledge and Attitudes Towards Haemophilia: The Family Side and Role of Haemophilia Societies
Authors: Pandey Gouri Shanker , Panigrahi Inusha , Phadke Shubha R. , Mittal Balraj
Published: October 2003

Objectives: A pilot study to evaluate the knowledge about haemophilia in the families enrolled in the Lucknow Haemophilia Society (India), and to assess their attitudes towards prenatal diagnosis (PND). Methods: A questionnaire to assess the knowledge about haemophilia (questionnaire A) and another questionnaire to assess the attitude towards PND (questionnaire B) were distributed. PND was performed by DNA-based linkage analysis. Results: There was a positive correlation between the knowledge about the disease and the frequency of attending the monthly meetings of the society. The majority of respondents felt that they would opt for termination of pregnancy if the fetus was affected. Conclusion: Haemophilia societies act as strong media in educating affected families. Multiple factors affect the attitude towards PND and abortion of affected fetuses.
Hearing Preservation after Inner Ear Gene Therapy: The Effect of Vector and Surgical Approach
Authors: Praetorius Mark , Baker Kim , Weich Corina M. , Plinkert Peter K. , Staecker Hinrich
Published: October 2003

Over seventy studies have examined the potential of gene therapy in the inner ear. For the most part, they have focused on adenoviral vectors and delivery into the cochlea. Most studies have emphasized looking at the expression of marker genes driven by a CMV promoter and have used first-generation adenoviral constructs. E1/E3/E4 deleted adenoviral vectors carrying the green fluorescent protein (GFP) gene were injected into the round window, the basal turn of the cochlea (via a cochleostomy) or into the superior semicircular canal. Hearing was then tested 24 h after viral gene transfer. Large vector titers in small volumes of fluid were well tolerated with the round window approach resulting in complete hearing preservation with transfer of GFP to hair cells and spiral ganglion cells. Injection of comparable doses of vector into a basal turn cochleostomy resulted in high-frequency hearing loss. Addition of a pancaspase inhibitor protected hearing when larger volumes of fluid were administered to the inner ear.
Population Frequencies of Single Nucleotide Polymorphisms (SNPs) in Immuno-Modulatory Genes
Authors: Martin A.-M. , Athanasiadis G. , Greshock J.D. , Fisher J. , Lux M.P. , Calzone K. , Rebbeck T.R. , Weber B.L.
Published: October 2003

Inherited polymorphisms in immuno-modulatory genes may contribute to variations in immune function and genetic susceptibility for complex diseases, including cancer. We report results from a comprehensive study to discover novel single nucleotide polymorphisms (SNPs) and to estimate allelic frequency for both novel and known coding and regulatory region SNPs in genes encoding proteins that have been implicated in the immune response to tumors. We identified 12 novel nucleotide substitution variants and one deletion variant in 17 genes analyzed (TGFβR, β2M, IFNγ, TNFα, TNFαR, LTα, IL-6, IL-12, IL-2, IL-1α, IL-1β, IL-1RN, IL-10, CTLA4, CD40L, Fas and FasL). We determined the frequency of these novel polymorphisms, as well as 17 previously identified polymorphisms, in a control sample of 158 individuals, approximately half of which were Caucasian (n = 74) and half of which were African American (n = 84). Significant differences in allele frequencies were observed between the two racial groups for 13/17 genes tested. These allelic variations maybe associated with alterations in immune function and thus susceptibility to a number of complex disease states such as cancer.
Shared Territories: An Element of Culturally Sensitive Practice
Authors: Pickering Marisue
Published: October 2003

Culturally sensitive practice is expected of all professionals whether working domestically or internationally. This essay explores concepts relative to such practice, specifically discussing ‘shared territories’, multidimensionality, partnership, and ethnocentrism, and arguing for a view that places all of humanity in the diversity mix. The author writes out of her role as an academician with responsibilities for preparing students for future practice.
Cross-Cultural Practice: What Is It Really About?
Authors: Pillay Mershen
Published: October 2003

The idea of cross-cultural practice, as it occurs between practitioners and their clients, is problematical. The notion of culture is analysed relative to our professions’ theories of knowledge production. Practitioners use ‘culture’ to refer to ‘linguistic’, ‘racial’, and ‘ethnic’ factors. An alternative, wider definition of what constitutes culture is offered in this paper. Furthermore, cross-cultural practice is evaluated against our dominant use of an empirical science to understand people and their lives. An analysis of the processes we use within our clinical relationship is provided. Empirical processes (disothering, reductionism, and essentialism) are discussed and evaluated for their coincidental relationship to colonial thinking about culture. A theoretical framework referred to as the Relationship of Labouring Affinities is introduced as a conceptual alternative to re-position how practitioners work with their clients.