bluuebunny/crossref_metadata_2025_split huggingface dataset:
A school‐based harm minimization smoking intervention trial: outcome results
Authors: Hamilton Greg , Cross Donna , Resnicow Ken , Hall Margaret 
Published: April 2005

ABSTRACTAims  To determine the impact of a school‐based harm minimization smoking intervention compared to traditional abstinence‐based approaches.Design, setting and participants  A school‐based cluster randomized trial was conducted in Perth, Western Australia in 30 government high schools from 1999 to 2000. Over 4000 students were recruited to participate and schools were assigned randomly to either the harm minimization intervention or a standard abstinence‐based programme.Intervention  The harm minimization intervention comprised eight 1‐hour lessons over 2 years, quitting support from school nurses and enactment of policies to support programme components. Comparison schools implemented standard abstinence‐based programmes and policies.Measures  Cigarette smoking was categorized at two levels: regular smoking, defined as smoking on 4 or more days in the previous week; and 30‐day smoking as any smoking within the previous month.Findings  At immediate post‐test (20 months post‐baseline), after accounting for baseline differences, school‐level clustering effects, socio‐economic status, gender and family smoking, intervention students were less likely to smoke regularly [OR = 0.51, 95% confidence interval (CI) = 0.36, 0.71] or to have smoked within the previous 30 days (OR = 0.69, 95% CI = 0.53, 0.91).Conclusion  The school‐based adolescent harm minimization intervention appears to have been more effective than the abstinence‐based social influences programme at reducing regular smoking.
Drug use among female sex workers in Hanoi, Vietnam
Authors: Tran Trung Nam , Detels Roger , Long Hoang Thuy , Lan Hoang Phuong 
Published: April 2005

ABSTRACTAims  To describe the drug use practices among female sex workers (FSWs) in Hanoi and to identify factors associated with their drug injecting.Design, setting and particicipants  A two‐stage cluster survey of 400 FSWs was conducted from June to September, 2002. Participating FSWs were both establishment‐ (160) and street‐based (240), who were practising in seven urban and one suburban districts of Hanoi.Measurements  Subjects were interviewed face to face using a structured questionnaire.Findings  Among the middle‐class FSWs, 27% used drugs, of whom 79% injected. Among low‐class FSWs, 46% used drugs and 85% injected. Among drug‐using FSWs, 86% had started using drugs within the past 6 years. Among drug‐injecting FSWs, 81% had started injecting within the past 4 years. Cleaning of injecting equipment was not common among those who shared. Having drug‐injecting ‘love mates’, drug‐using clients, longer residence in Hanoi, more clients and not currently cohabiting were found to be independently associated with drug injecting among FSWs.Conclusions  The high prevalence of injecting drug use among FSWs makes them susceptible to HIV infection, and is a threat to their clients. There is a strong relationship between drug‐using FSWs and male drug‐using clients and non‐client partners. Intervention to prevent drug use initiation among non‐drug‐using FSWs and harm reduction among drug‐using FSWs are urgently needed.
Automatic effects of alcohol cues on sexual attraction
Authors: Friedman Ronald S. , McCarthy Denis M. , Förster Jens , Denzler Markus 
Published: April 2005

ABSTRACTAims The present study tested whether suboptimal priming (which may be defined as ‘under viewing conditions rendering conscious identification highly improbable’) with alcohol‐related stimuli would activate existing expectancies about alcohol's effects on sexual desire. It was predicted that alcohol cues, relative to non‐alcohol cues, would activate expectancies of alcohol's aphrodisiac properties. We hypothesized that for men, stronger expectancies in this regard would predict an increased tendency to judge women as sexually attractive following the alcohol primes.Design Two experimental studies manipulated cue (alcoholversuscontrol) and rating dimension (attractivenessversusintelligence). Self‐reported alcohol expectancies of sexual desire were assessed approximately 1 month prior to the study. Study 2 assessed additional expectancy content domains.Setting and participants Study 1 comprised 82 undergraduate males and study 2 78 undergraduate males. Studies were conducted at the University of Missouri–Columbia, Columbia, Missouri, USA.Interventions In both experiments, male participants were suboptimally primed with either alcohol‐related or control words. Following this priming, they were presented with a series of photographs of young women and asked to either rate their attractiveness or their intelligence.Findings and conclusions In both studies, a three‐way interaction between cue, rating dimension and alcohol expectancies was found. Within the attractiveness rating condition a two‐way interaction was found, indicating that in this condition, stronger expectancies that alcohol increases sexual desire predicted higher attractiveness ratings after suboptimal exposure to alcohol primes. No effects emerged in the intelligence rating condition. Discussion centers on implications for sexual risk‐taking as well as a range of other non‐consumptive behaviors.
Cannabis use predicts future psychotic symptoms, and vice versa
Authors: Ferdinand Robert F. , Sondeijker Frouke , Van Der Ende Jan , Selten Jean‐Paul , Huizink Anja , Verhulst Frank C. 
Published: April 2005

ABSTRACTAims To assess if cannabis use is a risk factor for future psychotic symptoms, and vice versa, in adolescents and young adults from the general population.Design Cohort study.Setting/participants ‘Zuid Holland’ study, a 14‐year follow‐up study of 1580 initially 4–16‐year‐olds who were drawn randomly from the Dutch general population. Because cannabis use is generally condoned in the Netherlands, false‐negative reports of cannabis use may occur less frequently than in countries with stricter drug policies, which supports the value of the present study.Measurements Life‐time cannabis use and psychotic symptoms, assessed with the Composite International Diagnostic Interview (CIDI).Findings Cannabis use, in individuals who did not have psychotic symptoms before they began using cannabis, predicted future psychotic symptoms (hazard ratio = 2.81; 95% confidence interval = 1.79–4.43). However, psychotic symptoms in those who had never used cannabis before the onset of psychotic symptoms also predicted future cannabis use (hazard ratio = 1.70; 95% confidence interval = 1.13–2.57).Conclusions The results imply either a common vulnerability with varying order of onset or a bi‐directional causal relationship between cannabis use and psychosis. More research on patterns and timings of these relationships is needed to narrow down the possibilities.
In vitro analysis of sequence requirements for the excision reaction of the Bacteroides conjugative transposon, CTnDOT
Authors: DiChiara Jeanne M. , Salyers Abigail A. , Gardner Jeffrey F. 
Published: April 2005

SummaryCTnDOT, a Bacteroides conjugative transposon (CTn), initiates its transfer by excising to form a circular intermediate. This process has been shown to be complex, involving an unusual DNA intermediate with a short region of heterology and several CTn‐encoded proteins. No information was available, however, about the sizes or sequence requirements of the att sites (attL and attR) at the ends of the integrated element where the processing occurs during excision. Using a newly developed in vitro competition excision assay, we have now localized attL to 153 bp and attR to 179 bp. Excision of CTnDOT involves staggered cuts that produce 5 bp chromosomal sequences at either end of the CTn. These 5 bp sequences (coupling sequences) form a region of heterology in the excised circular intermediate. Site‐directed mutations that made the coupling sequences complementary and removed the region of heterology had no effect on excision. Thus, heterology is not essential. Mutagenesis of sequences adjacent to the coupling sequences revealed a 6 bp site in attR that was essential for excision. Mutating the analogous region in attL had little effect on excision. Regions within the attL site that appear to play a role in excision were found by introducing small insertions (phasing mutations) that could interfere with protein–protein or protein–DNA interactions. Similar insertion mutations in attR had no significant effect on excision. These results support the hypothesis that the CTnDOT excision reaction is asymmetrical with respect to likely protein binding sites and involves multiple protein–DNA interactions.
An unusual primary sigma factor in the Bacteroidetes phylum
Authors: Vingadassalom Didier , Kolb Annie , Mayer Claudine , Rybkine Tania , Collatz Ekkehard , Podglajen Isabelle 
Published: April 2005

SummaryThe presence of housekeeping gene promoters with a unique consensus sequence in Bacteroides fragilis, previously described by Bayley et al. (2000, FEMS Microbiol Lett 193: 149–154), suggested the existence of a particular primary sigma factor. The single rpoD‐like gene observed in the B. fragilis genome, and similarly in those of other members of the Bacteroidetes phylum, was found to be essential. It encodes a protein, σABfr, of only 32.7 kDa that is produced with equal abundance during all phases of growth and was concluded to be the primary sigma factor. σABfr and its orthologues in the Bacteroidetes are unusual primary sigma factors in that they lack region 1.1, have a unique signature made up of 29 strictly identical amino acids and are the only RpoD factors that cluster with the RpoS factors. Although binding to the Escherichia coli core RNA polymerase, σABfr does not support transcription initiation from any promoter when it is part of the heterologous holoenzyme, while in the reconstituted homologous holoenzyme it does so only from typical B. fragilis, including rrs, promoters but not from the lacUV5 or RNA I promoters.
A conserved set of pilin‐like molecules controls type IV pilus dynamics and organelle‐associated functions in Neisseria gonorrhoeae
Authors: Winther‐Larsen Hanne C. , Wolfgang Matthew , Dunham Steven , Van Putten Jos P. M. , Dorward David , Løvold Cecilia , Aas Finn Erik , Koomey Michael 
Published: April 2005

SummaryType IV pili (Tfp) play central roles in prokaryotic cell biology and disease pathogenesis. As dynamic filamentous polymers, they undergo rounds of extension and retraction modelled as pilin subunit polymerization and depolymerization events. Currently, the molecular mechanisms and components influencing Tfp dynamics remain poorly understood. Using Neisseria gonorrhoeae as a model system, we show that mutants lacking any one of a set of five proteins sharing structural similarity to the pilus subunit are dramatically reduced in Tfp expression and that these defects are suppressed in the absence of the PilT pilus retraction protein. Thus, these molecules are not canonical assembly factors but rather act as effectors of pilus homeostasis by promoting extension/polymerization events in the presence of PilT. Furthermore, localization studies support the conclusion that these molecules form a Tfp‐associated complex and influence levels of PilC, the epithelial cell adhesin, in Tfp‐enriched shear fractions. This is the first time that the step at which individual pilin‐like proteins impact on Tfp expression has been defined. The findings have important implications for understanding Tfp dynamics and fundamental Tfp structure/function relationships.
Clustering requires modified methyl‐accepting sites in low‐abundance but not high‐abundance chemoreceptors of Escherichia coli
Authors: Lybarger Suzanne R. , Nair Usha , Lilly Angela A. , Hazelbauer Gerald L. , Maddock Janine R. 
Published: April 2005

SummaryChemotaxis signalling complexes of Escherichia coli, composed of chemoreceptors, CheA and CheW, form clusters located predominately at cell poles. As the only kind of receptor in a cell, high‐abundance receptors are polar and clustered whereas low‐abundance chemoreceptors are polar but largely unclustered. We found that clustering was a function of the cytoplasmic, carboxyl‐terminal domain and that effective clustering was conferred on low‐abundance receptors by addition of the ∼20‐residue sequence from the carboxyl terminus of either high‐abundance receptor. These sequences are different but share a carboxyl‐terminal pentapeptide that enhances adaptational covalent modification and allows a physiological balance between modified and unmodified methyl‐accepting sites, implying that receptor modification might influence clustering. Thus we investigated directly effects of modification state on chemoreceptor clustering. As the sole receptor type in a cell, low‐abundance receptors were clustered only if modified, but high‐abundance receptors were clustered independent of extent of modification. This difference could mean that the two receptor types are fundamentally different or that they are poised at different positions in the same conformational equilibrium. Notably, no receptor perturbation we tested altered a predominant location at cell poles, emphasizing a distinction between determinants of clustering and polar localization.
Characterization of TetD as a transcriptional activator of a subset of genes of the Escherichia coli SoxS/MarA/Rob regulon
Authors: Griffith Kevin L. , Becker Stephen M. , E. Wolf Richard 
Published: April 2005

SummaryIn Escherichia coli, SoxS, MarA and Rob form a closely related subset of the AraC/XylS family of positive regulators, sharing ∼42% amino acid sequence identity over the length of SoxS and the ability to activate transcription of a common set of target genes that provide resistance to redox‐cycling compounds and antibiotics. On the basis of its ∼43% amino acid sequence identity with SoxS, MarA and Rob, TetD, encoded by transposon Tn10, appears to be a fourth member of the subset. However, although its expression has been shown to be negatively regulated by TetC and not inducible by tetracycline, the physiological function of TetD is unknown. Accordingly, in the work presented here, we initiate a molecular characterization of TetD. We show that expression of TetD activates transcription of a subset of the SoxS/MarA/Rob regulon genes and confers resistance to redox‐cycling compounds and antibiotics. We show that mutations in the putative TetD binding site of a TetD‐activatable promoter and a mutation in the protein's N‐terminal DNA recognition helix interfere with transcription activation, thereby indicating that TetD directly activates target gene transcription. Finally, we show that TetD, like SoxS and MarA, is intrinsically unstable; however, unlike SoxS and MarA, TetD is not degraded by Lon or any of the cell's known cytoplasmic ATP‐dependent proteases. Thus, we conclude that TetD is a bona fide member of the SoxS/MarA/Rob subfamily of positive regulators.
Compensatory role of PspA, a member of the phage shock protein operon, in rpoE mutant Salmonella enterica serovar Typhimurium
Authors: Becker Lynne A. , Bang Iel‐Soo , Crouch Marie‐Laure , Fang Ferric C. 
Published: April 2005

SummaryσE is an alternative sigma factor that responds to and ameliorates extracytoplasmic stress. In Salmonella enterica serovar Typhimurium (S. Typhimurium), σE is required for oxidative stress resistance, stationary‐phase survival and virulence in mice. Microarray analysis of stationary‐phase gene expression in rpoE mutant bacteria revealed a dramatic increase in expression of pspA, a member of the phage shock protein (psp) operon. The psp operon can be induced by filamentous bacteriophages or by perturbations of protein secretion, and is believed to facilitate the maintenance of proton motive force (PMF). We hypothesized that increased pspA expression may represent a compensatory response to the loss of σE function. Increased pspA expression was confirmed in rpoE mutant Salmonella and also observed in a mutant lacking the F1F0 ATPase. Alternatively, expression of pspA could be induced by exposure to CCCP, a protonophore that disrupts PMF. An rpoE pspA double mutant strain was found to have a stationary‐phase survival defect more pronounced than that of isogenic strains harbouring single mutations. The double mutant strains were also more susceptible to killing by CCCP or by a bactericidal/permeability‐increasing protein (BPI)‐derived anti‐microbial peptide. Using fluorescence ratio imaging, differences were observed in the Δψ of wild‐type and rpoE or pspA mutant bacteria. These findings suggest that pspA expression in S. Typhimurium is induced by alterations in PMF and a functional σE regulon is essential for the maintenance of PMF.
Antibodies Against Extractable Nuclear Antigen in Non‐Hodgkin Lymphoma Patients
Authors: Gergely L. , Dankó A. , Csípõ I. , Váróczy L. , Sipka S. , Zeher M. , Illés Á. 
Published: April 2005

AbstractAutoantibodies are found at higher frequency in malignant lymphoproliferative diseases and also the association of these diseases with autoimmunity is documented. However precise mechanisms are not yet understood beyond these findings. We measured anti‐extractable nuclear antigen (ENA) antibodies in non‐Hodgkin's lymphoma patients before, during and after chemotherapy and compared these values to healthy controls. Sixty six lymphoma patients' data were compared with 30 healthy patients' data. ENA levels were significantly elevated in untreated lymphoma patients compared with healthy controls (1.85 U/l versus 0.68 U/l, P < 0.05). This increase could be observed during and after treatment as well. Those patients who responded well to initial chmeotherapy were demonstrated with gradually increasing ENA antibody titers compared with the rest of patients, where a gradual decrease in titer was found. These findings are not yet statistically significant, but may help us further understand immunological reactions beyond the treatment of malignant lymphomas.
Immunology of Cutaneous Vasculitis Associated with both Etanercept and Infliximab
Authors: Srivastava M. D. , Alexander F. , Tuthill R. J. 
Published: April 2005

AbstractTargeted inhibition of tumour necrosis factor‐α (TNF‐α) is an effective therapy in rheumatoid arthritis and Crohn's disease (CD). Infliximab, a monoclonal murine‐human chimeric antibody to TNF‐α, and etanercept, a fusion protein of two p75 chains of the TNF receptor II and the Fc portion of IgG1, are generally well tolerated. Rarely does clinically significant autoimmunity, including drug‐induced lupus and vasculitis occur. Immunologic mechanisms underlying the development of autoimmunity in the presence of such powerful immunosuppressants are unknown. We describe a patient with CD, who developed cutaneous vasculitis on etanercept, which worsened significantly with switch to infliximab. Investigation of the associated systemic and local immune response demonstrated the absence of human antichimera antibodies, but mRNA for T‐helper 1 cytokines, chemokines and defensins in the skin and elevated angiogenesis factors in the serum, as determined by reverse‐transcriptase polymerase chain reaction and enzyme‐linked immunosorbent assay. Histopathology revealed a lymphocytic vasculitis composed of T cells. A permanent B‐cell line (MD‐B) producing extremely high amounts of chemokines and interleukin‐6 was established from this patient's peripheral blood. Lesions progressed despite discontinuation of the drugs and (40 mg/day) prednisone but almost completely resolved with single dose of (0.1 mg/kg) intravenous dexamethasone, which may be therapy of choice for this reaction. A few lesions (<10) have recurred intermittently over 4 years of follow‐up, suggesting possible persistence of this TNF‐inhibitor‐triggered autoimmune disease.
Sodium Alginate as a Novel Therapeutic Option in Experimental Colitis
Authors: Mirshafiey A. , Khodadadi A. , Rehm B. H. , Khorramizadeh M. R. , Eslami M. B. , Razavi A. , Saadat F. 
Published: April 2005

AbstractThe potential therapeutic effect of low‐viscosity sodium alginate (LVA) was studied in a rat model of acute colitis induced by intracolonic administration of acetic acid. This experimental model produced a significant ulcerative colitis. Induction of colitis also significantly enhanced the serum and colonic mucosal cytokine (IL‐6 and TNF‐α) and eicosanoid (LTB4 and PGE2) levels, which paralleled with the severity of colitis. LVA solution was administered orally as drinking water at concentration of 0.5% (W/V) for 1 week. The tolerability and inhibitory effect of LVA on matrix metalloproteinase‐2 (MMP‐2) were tested using WEHI‐164 cell line and zymography method. The results showed that LVA therapy is able to significantly reduce colonic damage score, histological lesion, serum and colonic mucosal IL‐6, TNF‐α, LTB4 and PGE2 levels in treated group compared with nontreated controls. Moreover, in vitro examinations revealed that treatment with LVA could diminish MMP‐2 activity. It is concluded that LVA is able to suppress acetic acid‐induced colitis in rats. Some of the action of LVA may be associated with its inhibitory effects on cytokine and eicosanoid production and MMP‐2 activity. Our data suggest that LVA could potentially be a novel therapeutic option for inflammatory bowel disease.
Cytokine mRNA Expression and Iron Status in Children Living in a Malaria Endemic Area
Authors: Nyakeriga A. M. , Williams T. N. , Marsh K. , Wambua S. , Perlmann H. , Perlmann P. , Grandien A. , Troye‐Blomberg M. 
Published: April 2005

AbstractIron deficiency has been reported to affect both malaria pathogenesis and cell‐mediated immune responses; however, it is unclear whether the protection afforded by iron deficiency is mediated through direct effects on the parasite, through immune effector functions or through both. We have determined cytokine mRNA expression levels in 59 children living in a malaria endemic area on the coast of Kenya who we selected on the basis of their biochemical iron status. Real‐time quantitative reverse transcriptase polymerase chain reaction analysis of cytokine mRNA levels of peripheral blood mononuclear cells (PBMC) obtained from these children showed an association between interleukin‐4 (IL‐4) mRNA levels and all the biochemical indices of iron that we measured. Furthermore, IL‐10 mRNA was higher in parasite blood smear‐positive children than in blood smear‐negative children irrespective of their iron status. This study suggests that IL‐4 expression by PBMC may be affected by iron status.
Effect of LACK and KMP11 on IFN‐γ Production by Peripheral Blood Mononuclear Cells from Cutaneous and Mucosal Leishmaniasis Patients
Authors: Carvalho L. P. , Passos S. , Dutra W. O. , Soto M. , Alonso C. , Gollob K. J. , Carvalho E. M. , Ribeiro de Jesus A. 
Published: April 2005

AbstractThe immune modulatory properties of recombinant antigens Kinetoplasmid membrane protein‐11 (KMP11) and Leishmania homologue of receptors for activated C kinase (LACK) in cutaneous leishmaniasis (CL) and mucosal leishmaniasis (ML) patients were evaluated. The mean levels of interferon‐γ (IFN‐γ) in soluble leishmania antigen (SLA) stimulated peripheral blood mononuclear cells (PBMC) of ML and CL patients were 5625 ± 2333 pg/ml and 4422 ± 3665 pg/ml, respectively. IFN‐γ was not detected in cultures stimulated with KMP11 or LACK. Interleukin‐10 (IL‐10) concentration in SLA, KMP11 and LACK‐stimulated PBMC of ML patients was 13 ± 12 pg/ml, 285 ± 388 pg/ml and 802 ± 483 pg/ml, respectively. Addition of KMP11 or LACK to SLA‐stimulated PBMC of CL and ML patients enhanced IL‐10 production (P < 0.05). Addition of KMP11 decreased IFN‐γ levels by 52% in CL patients and by 19% in ML patients. Addition of LACK to SLA‐stimulated cultures decreased IFN‐γ levels by 58% in CL patients and by 30% in ML patients. Neutralization of IL‐10 abrogated the downregulatory effect of LACK and KMP11. The modulatory properties of LACK and KMP11 are due to induction of IL‐10 production and may be helpful for attenuating chronic inflammatory diseases. However, in some clinical conditions, as demonstrated for ML, these molecules are not able to suppress the IFN‐γ response, even inducing IL‐10 production.