bluuebunny/crossref_metadata_2025 huggingface dataset:
A school‐based harm minimization smoking intervention trial: outcome results
Authors: Hamilton Greg , Cross Donna , Resnicow Ken , Hall Margaret
Published: April 2005

Aims  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

Aims  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

Aims 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

Aims 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.
Lamivudine vs lamivudine and interferon combination treatment of HBeAg(−) chronic hepatitis B
Authors: Yurdaydin C. , Bozkaya H. , Çetinkaya H. , Şahin T. , Karaoğuz D. , Törüner M. , Erkan Ö. , Heper A. O. , Erden E. , Bozdayi A. M. , Uzunalimoğlu Ö.
Published: April 2005

Summary.  To determine whether combination treatment of HBeAg(−) chronic hepatitis B is beneficial we studied 78 patients with HBeAg(−), HBV DNA‐positive chronic hepatitis B who were randomized to lamivudine, 100 mg, qd, for 12 months or lamivudine–interferon (9 MU, t.i.w.) in combination. In the combination arm, 2 months of lamivudine treatment preceded 10 months of combination treatment. Biochemical, virologic and histologic responses were assessed at the end of treatment, after six and a median 27 months of drug‐free follow‐up (short‐ and long‐term follow‐up, respectively). Virologic response was defined as undetectable HBV DNA with a hybridization assay and biochemical response as normal alanine aminotransferase (ALT). Change in HBV DNA was also assessed by real‐time polymerase chain reaction (PCR). Presence of YMDD mutants at the end of treatment was investigated with a line probe assay. Both treatment regimes led to a median 2 log decline in HBV DNA levels. Virologic end of treatment responses were 90 and 92% with mono‐ and combination treatment, respectively. Corresponding virologic responses at short‐ and long‐term follow‐up were 59 and 54%, and 27 and 25%, respectively. Patients having a baseline HBV DNA value ≥200 pg/mL were more likely to relapse within 6 months off therapy than those patients with a baseline HBV DNA level <200 pg/mL (P = 0.041). YMDD mutants were observed in 53% of patients receiving lamivudine compared with 24% of patients receiving the combination regime (P = 0.017). In conclusion, efficay of combination treatment is similar to lamivudine monotherapy. However, combination treatment decreases the development of YMDD mutant strains compared with lamivudine monotherapy.
Inhibition of hepatitis B virus replication in 2.2.15 cells by expressed shRNA
Authors: Ren X.‐R. , Zhou L.‐J. , Luo G.‐B. , Lin B. , Xu A.
Published: April 2005

Summary.  Hepatitis B virus (HBV) infection is a worldwide health problem. To determine whether RNA interference (RNAi) could inhibit ongoing HBV replication in 2.2.15 cells, we constructed shRNA‐producing vector pU6P based on the mouse U6 RNA promoter and cloned 12 targeted sequences against HBV into the vector, resulting in a series of pU6‐siHBV vectors. The recombinant vectors were transfected into 2.2.15 cells, HBsAg and HBeAg in cultured media were assayed using enzyme‐linked immunosorbent assay at various days after transfection. The amount of HBV DNA in the culture medium was quantitated by real‐time polymerase chain reaction. HBsAg and HBeAg expression were inhibited by 72.8 ± 5.4% (P = 0.00003) and 55.8 ± 6.2% (P = 0.000026), respectively, 4 days after transfection with pU6‐siHBV5. The greatest inhibition of HBV DNA was decreased by approximately 1.9‐fold (P = 0.013) on day 6 post transfection with pU6‐siHBV11 compared with that of empty vector. No change was found for HBV protein expression and DNA replication on pU6‐siGFP (negative control) transfected cells. Our data demonstrate that the transfection of HBV‐targeted shRNA‐producing vector in 2.2.15 cells could inhibit the HBV protein expression and HBV DNA replication specifically. RNAi may be considered as a potential antiviral approach for human HBV infection.
Comparison of a 6‐month course peginterferon α‐2b plus ribavirin and interferon α‐2b plus ribavirin in treating Chinese patients with chronic hepatitis C in Taiwan
Authors: Lee S.‐D. , Yu M.‐L. , Cheng P.‐N. , Lai M.‐Y. , Chao Y.‐C. , Hwang S.‐J. , Chang W.‐Y. , Chang T.‐T. , Hsieh T.‐Y. , Liu C.‐J. , Chen D.‐S.
Published: April 2005

Summary.  Previous studies in Caucasian patients showed treatment of chronic hepatitis C with pegylated interferon/ribavirin was well tolerated, and produced a higher response rate especially in genotype 1 infections. However, it is unknown whether this conclusion can be extrapolated to patients with Chinese ethnic origin. A total of 153 patients with biopsy‐proven chronic hepatitis C were randomly assigned to receive either weekly injection of peginterferon α‐2b 1.5 mcg/kg plus oral ribavirin (1000 or 1200 mg/day, depending on body weight) (PEG group, n = 76) or 3 MU of interferon α‐2b t.i.w. plus ribavirin (IFN group, n = 77) for 24 weeks. Sustained virological response (SVR) was defined as the sustained disappearance of serum hepatitis C virus (HCV) RNA at 24 weeks after the end of treatment by polymerase chain reaction assay. Baseline demographic, viral and histological characteristics were comparable between the two groups. Using an intent‐to‐treat analysis, HCV genotype 1 patients showed a significantly higher SVR in patients receiving PEG‐IFN rather than IFN (65.8%vs 41.0%, P = 0.019), but no difference was found in genotype non‐1 patients (PEG vs IFN: 68.4%vs 86.8%, P = 0.060). Genotype 1 patients (28.6%) in the PEG‐IFN group relapsed, as compared with 52.9% in the IFN group (P = 0.040). Multivariate analyses showed early virological response at week 12 of therapy and genotype non‐1 were significant predictors to SVR. As compared with the IFN group, patients receiving PEG‐IFN had a significantly higher rate of discontinuation, dose reduction, fever, headache, insomnia, leucopenia and thrombocytopenia. In genotype 1 chronic hepatitis C Chinese patient, PEG‐IFNα2b ribavirin had significantly better SVR and lower relapse rate when compared to IFN/ribavirin. Both regimens can be recommended for genotype non‐1 chronic hepatitis C Chinese patients. However, a higher rate of adverse events and discontinuance of therapy were noted in patients treated with PEG‐IFNα2b ribavirin.
A randomized controlled trial of pegylated interferon α‐2a (40 KD) or interferon α‐2a plus ribavirin and amantadine vs interferon α‐2a and ribavirin in treatment‐naïve patients with chronic hepatitis C
Authors: Mangia A. , Ricci G. L. , Persico M. , Minerva N. , Carretta V. , Bacca D. , Cela M. , Piattelli M. , Annese M. , Maio G. , Conte D. , Guadagnino V. , Pazienza V. , Festi D. , Spirito F. , Andriulli A.
Published: April 2005

Summary.  We determined whether triple therapy comprising amantadine (AMA), ribavirin (RBV) and either peginterferon (PEG‐IFN) α‐2a or conventional IFN α‐2a would improve sustained virological response (SVR) rates over dual therapy with IFN α‐2a and RBV in patients with chronic HCV infection. A total of 362 treatment‐naïve patients were randomized to 48 weeks of treatment with: PEG‐IFN α‐2a 180 μg/week (group A) or IFN α‐2a 3 MU tiw (groups B and C). All patients received RBV 1000 or 1200 mg/day and those in groups A and B received AMA 200 mg/day. SVR was defined as an undetectable HCV RNA after 24 weeks of untreated follow‐up. At the end of therapy, 74.4% (95% CI 0.66–0.82) of patients in group A were HCV RNA‐negative compared with 42.5% (95% CI 0.33–0.50) of those in group B (P = 0.0001) and 48.8% (95% CI 0.40–0.56) of those in group C. SVR was achieved in a significantly greater proportion of patients in group A compared with groups B and C: 65.3% (95% CI 0.53–0.56), 33.3% (95% CI 0.25–0.41) and 44.6% (95% CI 0.36–0.53; P = 0.0001) respectively. In patients with genotype 1, SVR rates were 55.2, 22.8 and 28.8% with the three regimens respectively. Factors independently associated with SVR were HCV genotype 2 or 3, therapy with PEG‐IFN, female gender and age. In treatment‐naïve patients with chronic hepatitis C, triple therapy with PEG‐IFN α‐2a, RBV and AMA produces higher SVR than dual or triple therapy with conventional IFN α‐2a.
Determinants of acquiring hepatitis A virus disease in a large Italian region in endemic and epidemic periods
Authors: Lopalco P. L. , Malfait P. , Menniti‐Ippolito F. , Prato R. , Germinario C. , Chironna M. , Quarto M. , Salmaso S.
Published: April 2005

Summary.  Viral hepatitis A is endemic in Puglia region (southeast Italy). Over the last 13 years, annual incidence rates have ranged from 4 to 138 per 100 000 inhabitants and periodical regional epidemics have been described. Between 1 January 1996 and 31 December 1997 over 11 000 cases of hepatitis A were reported accounting for an annual incidence rate over 130/100 000. To identify exposures during the epidemics, a case–control study was performed in two different rounds and since 1997, an enhanced surveillance system has permitted the monitoring of exposures of subsequent cases. Raw seafood consumption was identified as the major risk factor for hepatitis A. Adjusted odds ratio and 95% confidence intervals for this exposure from the first round of the case–control study was 38.6 (12.2–122.4) and for the second round for consumption of raw mussels it was 30.7 (16.0–52.0). Hepatitis A epidemiology in Puglia is consistent with an endemic situation sustained by locally contaminated seafood consumed raw and by the recurrence of large epidemics, where size is influenced by the accumulation of susceptible subjects in the population.
Apoptotic cytokeratin 18 neoepitopes in serum of patients with chronic hepatitis C
Authors: Kronenberger B. , von Wagner M. , Herrmann E. , Mihm U. , Piiper A. , Sarrazin C. , Zeuzem S.
Published: April 2005

Summary.  In patients with chronic hepatitis C, alanine aminotransferase (ALT) levels do not accurately reflect the extent of liver inflammation. The discrepancy between ALT level and liver damage could be related to the mode of cell death. In the present study, we quantified serum levels of apoptotic cytokeratin 18 (CK‐18) neoepitopes that are generated by activated caspases during apoptosis. Apoptotic CK‐18 neoepitopes were quantified by enzyme linked immunosorbent assay in sera from patients with chronic hepatitis C and elevated ALT levels (n = 72), patients with chronic hepatitis C and persistently normal ALT levels (n = 27) and healthy controls (n = 19). Serum CK‐18 neoepitope levels were strongly correlated with ALT (r = 0.659, P < 0.0001) and the histology activity index (r = 0.374, P < 0.001). Patients with chronic hepatitis C and persistently normal ALT levels had higher apoptotic CK‐18 neoepitope levels than healthy controls (P = 0.03) but lower levels than patients with chronic hepatitis C and elevated ALT levels (P < 0.001). Highest serum CK‐18 neoepitope levels were observed in patients with cirrhosis (P = 0.002). Hence apoptotic CK‐18 neoepitopes in serum of patients with chronic hepatitis C are associated with ALT level and histological liver damage. Serum apoptotic CK‐18 neoepitope levels are elevated both in patients with chronic hepatitis C and elevated ALT levels as well as in patients with normal ALT levels indicating that also patients with chronic hepatitis C and normal ALT have an increased hepatocyte loss by apoptosis.
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

CTnDOT, 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

The 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

Type 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

Chemotaxis 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

In 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

σE 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

Autoantibodies 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

Targeted 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

The 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

Iron 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

The 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.
Complement Dependency of Splenic Localization of Pneumococcal Polysaccharide and Conjugate Vaccines
Authors: Breukels M. A. , Zandvoort A. , Rijkers G. T. , Lodewijk M. E. , Klok P. A. , Harms G. , Timens W.
Published: April 2005

The immune response to polysaccharides is initiated when polysaccharides bind complement factor C3d, and these polysaccharide–C3d complexes subsequently localize on splenic marginal zone B cells strongly expressing CD21 (complement receptor 2). Infants and children under the age of 2 years have low or absent expression of CD21 on their marginal zone B cells, and consequently do not adequately respond to polysaccharides. In contrast, polysaccharide–protein conjugate vaccines are able to induce antibodies at this young age. Conjugate vaccines apparently overcome the necessity for CD21–C3d interaction for an antipolysaccharide immune response.

We demonstrate in a rat model that localization of pneumococcal polysaccharides on splenic marginal zone B cells indeed is complement dependent. We also show that pneumococcal conjugates do not specifically localize on splenic marginal zone B cells and that splenic localization of polysaccharide conjugates is independent of the presence of complement. Thus, the induction of antipolysaccharide antibodies by conjugate vaccines apparently can occur independently of CD21–C3d interaction. These basic findings may explain the effectiveness of conjugated vaccines in young children and may open the way for their application in other patient groups.
Distinct Interethnic Differences in Immunoglobulin G Class/Subclass and Immunoglobulin M Antibody Responses to Malaria Antigens but not in Immunoglobulin G Responses to Nonmalarial Antigens in Sympatric Tribes Living in West Africa
Authors: Bolad A. , Farouk S. E. , Israelsson E. , Dolo A. , Doumbo O. K. , Nebié I. , Maiga B. , Kouriba B. , Luoni G. , Sirima B. S. , Modiano D. , Berzins K. , Troye‐Blomberg M.
Published: April 2005

The well‐established relative resistance to malaria observed in the Fulani as compared with other sympatric tribes in West Africa has been attributed to their higher levels of serum immunoglobulin (Ig) G antibodies to malarial antigens. In this study, we confirm and extend the previous findings by analyses of the levels of IgM, IgG and IgG subclasses of anti‐malarial antibodies in asymptomatic individuals of different sympatric tribes in Burkina Faso (Fulani/Mossi) and Mali (Fulani/Dogon). The Fulani showed significantly higher median concentrations of anti‐malarial IgG and IgM antibodies than the sympatric tribes at both locations. Although the overall subclass pattern of antibodies did not differ between the tribes, with IgG1 and IgG3 as dominant, the Fulani showed consistently significantly higher levels of these subclasses as compared with those of the non‐Fulani individuals. No significant differences were seen in the levels of total IgG between the tribes, but the Fulani showed significantly higher levels of total IgM than their neighbours in both countries. While the antibody levels to some nonmalarial antigens showed the same pattern of differences seen for antibody levels to malaria antigens, no significant such differences were seen with antibodies to other nonmalarial antigens. In conclusion, our results show that the Fulani in two different countries show higher levels of anti‐malarial antibodies than sympatric tribes, and this appears not to be a reflection of a general hyper‐reactivity in the Fulani.
A Meccano set approach of joining trpzip a water soluble β‐hairpin peptide with a didehydrophenylalanine containing hydrophobic helical peptide
Authors: Chetal P. , Chauhan V.S. , Sahal D.
Published: April 2005

Abstract:  A 16 residues long, water soluble, monomeric β‐hairpin peptide ‘trpzip’ (Cochran et al. Proc. Natl. Acad. Sci. U.S.A., 98 (2001), 5578), stabilized by tryptophan zipper has been linked via a tetraglycyl linker to a hydrophobic didehydrophenylalnine (ΔF) containing helical octapeptide. Circular dichroism studies of this 28 residues long peptide, ‘trpzipalpha’ (Ac‐GEWTWDDATKTWTWTE‐GGGG‐ΔFALΔFALΔFA‐NH2) in water have revealed the presence of both the β‐hairpin and the helical conformations. This is the first instance where a ΔF containing peptide has been found to display a helical fold in water. The fluorescence emission wavelengths of tryptophan in Ac‐G‐W‐G‐NH2, trpzip and trpzipalpha were 341.5, 332.8 and 332.6 nm, respectively. The fluorescence quantum yield of trpzip was 2.6‐fold higher than trpzipalpha suggesting that proximal interactions between the β‐hairpin and the helix caused the quenching of tryptophan fluorescence in the former by the ΔFs in the latter. The molar ellipticity of the far UV couplet characteristic of trpzip was reduced in trpzipalpha and the CD based thermal melting temperatures at 228 nm were 62 °C (trpzip) and 57 °C (trpzipalpha). A concentration‐dependent variable temperature CD study in water showed that in trpzipalpha, increasing temperature is detrimental to the β‐hairpin, but it augments the helical motif, perhaps by intermolecular oligomerization. Our results show that in water, trpzipalpha exhibits long‐range interactions between two different secondary structures. In contrast to trpzip, trpzipalpha has shown a greater tendency to oligomerize in water.
Specific binding of amyloid‐β‐protein to IMR‐32 neuroblastoma cell membrane
Authors: Inaba S. , Okada T. , Konakahara T. , Kodaka M.
Published: April 2005

In flow cytometry using two detecting methods, we have found that amyloid‐β‐protein(1–40) [Aβ(1–40)] has high affinity to IMR‐32 neuroblastoma cell membrane when it is aggregated to form β‐sheet conformation, whereas random coil small Aβ‐species has low affinity. The difference in the binding ability to the cell membranes well accounts for the cytotoxicity of Aβ(1–40); namely, aggregated β‐sheet Aβ(1–40) gives cytotoxicity higher than random coil Aβ(1–40). Specific binding between Aβ(1–40) and ganglioside GM1 of the raft‐like domain in lipid membrane is suggested from a surface plasmon resonance (SPR) experiment.
Probing the binding of the coumarin drugs using peptide fragments of DNA gyrase B protein
Authors: Garrido S.S. , Scatigno A. C. , Trovatti E. , Carvalho D.C. , Marchetto R.
Published: April 2005

Abstract:  Bacterial DNA gyrase, has been identified as the target of several antibacterial agents, including the coumarin drugs. The coumarins inhibit the gyrase action by competitive binding to the ATP‐binding site of DNA gyrase B (GyrB) protein. The high in vitro inhibitory potency of coumarins against DNA gyrase reactions has raised interest in studies on coumarin–gyrase interactions. In this context, a series of low‐molecular weight peptides, including the coumarin resistance‐determining region of subunit B of Escherichia coli gyrase, has been designed and synthesized. The first peptide model was built using the natural fragment 131–146 of GyrB and was able to bind to novobiocin (Ka = 1.8 ± 0.2 × 105/m) and ATP (Ka = 1.9 ± 0.4 × 103/m). To build the other sequences, changes in the Arg136 residue were introduced so that the binding to the drug was progressively reduced with the hydrophobicity of this residue (Ka = 1.3 ± 0.1 × 105/m and 1.0 ± 0.2 × 105/m for Ser and His, respectively). No binding was observed for the change Arg136 to Leu. In contrast, the binding to ATP was not altered, independently of the changes promoted. On the contrary, for peptide–coumarin and peptide–ATP complexes, Mg2+ appears to modulate the binding process. Our results demonstrate the crucial role of Arg136 residue for the stability of coumarin–gyrase complex as well as suggest a different binding site for ATP and in both cases the interactions are mediated by magnesium ions.
CLARIFYING HOMOLOGIES IN THE MAMMALIAN CEREBRAL CORTEX: THE CASE OF THE THIRD VISUAL AREA (V3)
Authors: Rosa Marcello GP , Manger Paul R
Published: April 2005

1. Experiments in mammalian models are the main source of information on the neural architecture underlying human visual perception, establishing scientific boundaries for the interpretation of experiments using non‐invasive techniques in humans and for the realistic modelling of visual processes. Thus, it is important to define the homology between visual areas in different species.

2. To date, relatively few visual areas can be defined with certainty across mammalian Orders. Here, we review the evidence pointing to the fact that the third visual area (V3; or area 19) is a crucial node of a system involved in shape recognition that exists in most, if not all, eutherian mammals.

3. The size and shape of area V3 are variable, even between species that belong to the same Order. Although some features of the visuotopic organization of V3 are constant (including the relative location of the representations of the upper and lower quadrant and correspondence between the anterior border and the representation of the vertical meridian of the visual field), others are variable between species and even individuals. A complex pattern of representation, involving topological discontinuities, can exist.

4. In addition to its location in relation to the first (V1) and second (V2) visual areas, the identification of V3 homologues can be aided by certain other features, including low myelination, weak cytochrome oxidase reactivity, response properties that are indicative in the processing of stimulus shape, relationship to clusters of neurons forming interhemispheric connections and projections from the koniocellular (W‐cell‐like) components of the lateral geniculate nucleus.

5. Recent research in primates has clarified the organization of the V3 homologue in members of this Order. Regions of cortex that were formerly thought to belong to V3 (including a densely myelinated region near the dorsal midline) are better considered as part of a separate dorsomedial area, involved in motion analysis and visuomotor integration. The redefined V3, which includes the ‘ventral posterior area’ and parts of the dorsolateral complex proposed by earlier studies, is very similar to V3 (area 19) of other species in terms of structure and function.
EUPHORBIA THYMIFOLIA SUPPRESSES HERPES SIMPLEX VIRUS‐2 INFECTION BY DIRECTLY INACTIVATING VIRUS INFECTIVITY
Authors: Yang Chien‐Min , Cheng Hua‐Yew , Lin Ta‐Chen , Chiang Lien‐Chai , Lin Chun‐Ching
Published: April 2005

1. The ethyl acetate (EtOAc) extract and 3‐O‐galloyl‐4,6‐(S)‐hexahydroxydiphenoyl‐d‐glucose (3OG46HG) of Euphorbia thymifolia Linnea have been shown to exhibit anti‐herpes simplex virus (HSV)‐2 activity in vitro. In the present study, we investigated the mode of action of these two compounds in suppressing HSV‐2 multiplication.

2. The results demonstrated that the EtOAc extract and 3OG46HG affected virus infectivity in a dose‐dependent manner. The EtOAc extract significantly reduced virus infectivity at a concentration of 4.0 µg/mL, whereas 3OG46HG obviously diminished virus infectivity at concentration of a 0.5 µg/mL. The virucidal ability of the EtOAc extract was affected by the incubation period, but not by the incubation temperature. In the case of the action of 3OG46HG against HSV‐2, the effects of incubation time and temperature were negligible.

3. In summary, the EtOAc extract and 3OG46HG of E. thymifolia are concluded to inhibit HSV‐2 multiplication by reducing virus infectivity.
15‐F2t‐ISOPROSTANE and 5‐F2t‐ISOPROSTANE ARE NOT TRIGGERS OF MYOCARDIAL PRECONDITIONING
Authors: Arnaud Claire , Cracowski Jean‐Luc , Hakim Ahmed , Durand Thierry , Guy Alexandre , Godin‐Ribuot Diane , Bessard Germain , Ribuot Christophe
Published: April 2005

1. Myocardial ischaemia–reperfusion in humans is associated with increased formation of 15‐F2t‐isoprostane and 5‐F2t‐isoprostane (15‐F2t‐IsoP and 5‐F2t‐IsoP, respectively). Whether this formation is relevant clinically remains controversial. The present study was performed in order to evaluate the ability of the isoprostanes 15‐F2t‐IsoP and 5‐F2t‐IsoP to reduce myocardial ischaemic injury in rat isolated heart.

2. Rats were divided into six groups. Hearts were excised, perfused retrogradely and pretreated with vehicle (ethanol 5.10−7 and 2.10−9 mol/L; n = 6), subjected to ischaemic preconditioning (n = 8) or pretreated with the isoprostanes 15‐F2t‐IsoP (3.10−10 and 3.10−7 mol/L; n = 8) or 5‐F2t‐IsoP (10−9 mol/L; n = 8). After a 5 min treatment−5 min washout period, hearts were submitted to 30 min global ischaemia, followed by a 120 min reperfusion period.

3. The infarct‐to‐ventricle zone ratio was significantly reduced in ischaemic preconditioned (20.6 ± 2.6%) compared with vehicle groups (44.5 ± 4.3 and 51.3 ± 2.5% in groups pretreated with 5.10−7 or 2.10−9 mol/L ethanol, respectively). Pretreatment with either isoprostane had no cardioprotective effect; the infarct‐to‐ventricle ratios were 43.1 ± 2.2, 49.4 ± 5.9 and 44.5 ± 5.0% for groups treated with 3.10−10 mol/L 15‐F2t‐IsoP, 3.10−7 mol/L 15‐F2t‐IsoP or 10−9 mol/L 5‐F2t‐IsoP, respectively.

4. These data provide evidence that the isoprostanes 15‐F2t‐IsoP and 5‐F2t‐IsoP are not implicated in early myocardial preconditioning at concentrations similar to those found in the human coronary sinus following coronary angioplasty.