bluuebunny/crossref_metadata_2025_split huggingface dataset:
IgG Subclass Responses in Childhood Helicobacter pylori Duodenal Ulcer: Evidence of T‐Helper Cell Type 2 Responses
Authors: Campbell David I. , Pearce Mark S. , Parker Louise , Thomas Julian E. 
Published: July 2004

ABSTRACTBackground.  Duodenal ulcer in adults chronically infected with Helicobacter pylori is associated with a polarized T‐helper cell type 1 (Th1) mucosal immune response, with a predominantly immunoglobulin G2 (IgG2) systemic specific response. It has been suggested that children colonized by H. pylori also produce a mucosal Th1 response, but there are few studies that have measured IgG subclass responses in children with duodenal ulcer.Materials and methods.  Seven children with endoscopically proven duodenal ulcer and H. pylori infection and 18 children with biopsy proven H. pylori infection but no duodenal ulcer had relative concentrations of IgG subclass responses (IgGsc) against H. pylori antigens measured by ELISA. Eighteen IgG seropositive adults acted as controls. The range of antigens recognised by IgG1 and IgG2 subclass responses were investigated by Western blots.Results.  There were no differences in mean IgGsc responses between children with or without duodenal ulcer. Adults produced an IgG2 predominant response. Western blots showed no qualitative differences in antigens recognised by IgG1 or IgG2.Conclusion.  Children with duodenal ulcer, in contrast to adults, produce an IgGsc response consistent with a mucosal Th2 response to H. pylori regardless of the presence of duodenal ulceration. This suggests that disease causation amongst children with H. pylori associated duodenal ulceration may not be dependant upon a mucosal Th1 biased response.
Stool Antigen Test for the Diagnosis of Helicobacter pylori Infection: a Systematic Review
Authors: Gisbert Javier P. , Pajares José María 
Published: July 2004

ABSTRACTOur aim was to review systematically the diagnostic accuracy of the Helicobacter pylori stool antigen test. Bibliographical searches were performed in several electronic databases and abstracts from congresses up to May 2003. Eighty‐nine studies (10,858 patients) evaluated the stool antigen test in untreated patients. Mean sensitivity, specificity, positive predictive value and negative predictive value were 91%, 93%, 92% and 87%, respectively. Analysis of the eight studies (1399 patients) in which pretreatment evaluation of the monoclonal stool antigen test was performed showed better (p < .001) results (96%, 97%, 96% and 97%, respectively), with a clearer distinction between positive and negative results. Thirty‐nine studies (3147 patients) evaluated the stool antigen test for the confirmation of H. pylori eradication 4–8 weeks after therapy, with accuracies of 86%, 92%, 76% and 93% for mean sensitivity, specificity, positive predictive value and negative predictive value, respectively. Results were similar when a gold standard based on at least two methods was used. Relatively low accuracy was reported in some posttreatment studies with the polyclonal stool antigen test. However, excellent results (p < .001) were achieved in all the six studies evaluating the monoclonal stool antigen test 4–8 weeks posttreatment. Results evaluating the stool antigen test < 4 weeks posttreatment are contradictory. Proton‐pump inhibitors seem to affect the accuracy of the stool antigen test. Sensitivity and/or specificity in patients with gastrointestinal bleeding may be suboptimal. The stool antigen test performs well in children. Finally, the stool antigen test seems to be a cost‐effective method.
Comparative Chemical and Biological Characterization of the Lipopolysaccharides of Gastric and Enterohepatic Helicobacters
Authors: Hynes Sean O. , Ferris John A. , Szponar Bogumila , Wadström Torkel , Fox James G. , O'Rourke Jani , Larsson Lennart , Yaquian Elisa , Ljungh Åsa , Clyne Marguerite , Andersen Leif P. , Moran Anthony P. 
Published: July 2004

ABSTRACTBackground.  The lipopolysaccharide of Helicobacter pylori plays an important role in colonization and pathogenicity. The present study sought to compare structural and biological features of lipopolysaccharides from gastric and enterohepatic Helicobacter spp. not previously characterized.Materials and methods.  Purified lipopolysaccharides from four gastric Helicobacter spp. (H. pylori, Helicobacter felis, Helicobacter bizzozeronii and Helicobacter mustelae) and four enterohepatic Helicobacter spp. (Helicobacter hepaticus, Helicobacter bilis, ‘Helicobacter sp. flexispira’ and Helicobacter pullorum) were structurally characterized using electrophoretic, serological and chemical methods.Results.  Structural insights into all three moieties of the lipopolysaccharides, i.e. lipid A, core and O‐polysaccharide chains, were gained. All species expressed lipopolysaccharides bearing an O‐polysaccharide chain, but H. mustelae and H. hepaticus produced truncated semirough lipopolysaccharides. However, in contrast to lipopolysaccharides of H. pylori and H. mustelae, no blood group mimicry was detected in the other Helicobacter spp. examined. Intra‐species, but not interspecies, fatty acid profiles of lipopolysaccharides were identical within the genus. Although shared lipopolysaccharide‐core epitopes with H. pylori occurred, differing structural characteristics were noted in this lipopolysaccharide region of some Helicobacter spp. The lipopolysaccharides of the gastric helicobacters, H. bizzozeronii and H. mustelae, had relative Limulus amoebocyte lysate activities which clustered around that of H. pylori lipopolysaccharide, whereas H. bilis, ‘Helicobacter sp. flexispira’ and H. hepaticus formed a cluster with approximately 1000–10,000‐fold lower activities. H. pullorum lipopolysaccharide had the highest relative Limulus amoebocyte lysate activity of all the helicobacter lipopolysaccharides (10‐fold higher than that of H. pylori lipopolysaccharide), and all the lipopolysaccharides of enterohepatic Helicobacter spp. were capable of inducing nuclear factor‐Kappa B(NF‐κB) activation.Conclusions.  The collective results demonstrate the structural heterogeneity and pathogenic potential of lipopolysaccharides of the Helicobacter genus as a group and these differences in lipopolysaccharides may be indicative of adaptation of the bacteria to different ecological niches.
Helicobacter pylori Infection and Immune Thrombocytopenic Purpura: an Update
Authors: Franchini Massimo , Veneri Dino 
Published: July 2004

ABSTRACTData are accumulating on the association between Helicobacter pylori infection and idiopathic thrombocytopenic purpura (ITP) and the significant increase in platelet count after bacterial eradication. The aim of this review was to consider the studies so far published on H. pylori infection and ITP in order to evaluate a possible correlation between these two conditions. A review of the literature showed that 278 out of the 482 ITP patients investigated (58%) were positive for H. pylori infection and that the bacterium was eradicated in 88% of cases. Eradication therapy was accompanied by a complete or partial platelet response in approximately half the cases. Overall, these data show that H. pylori eradication in patients with ITP is effective in increasing platelet count. However, because the studies so far published are few, are sometimes controversial and involve small series of patients, further studies on larger numbers of patients with longer follow‐up are needed to confirm these preliminary findings.
Polymorphism of the Helicobacter pylori feoB Gene in Korea: a Possible Relation with Iron‐Deficiency Anemia?
Authors: Jeon Byung Ha , Oh Yoo Joung , Lee Na Gyong , Choe Yon Ho 
Published: July 2004

ABSTRACTBackground.  Helicobacter pylori is a causative agent of gastritis, and H. pylori infection is thought to be correlated with iron‐deficiency anemia (IDA) at puberty. The H. pylori feoB gene product, a high‐affinity ferrous iron transporter, plays a central role in iron acquisition and virulence. This study was undertaken to analyze H. pylori feoB status according to clinical data, including antral gastritis with or without IDA.Methods.  Fourteen H. pylori‐positive patients aged from 10 to 18 years were categorized into subgroups based on the presence or absence of IDA. Eight patients were diagnosed as having IDA; the other six showed normal hematological findings. Genomic DNA was isolated from H. pylori cultured from each gastric biopsy specimen. Five sets of primers were used for the PCR amplification of the feoB gene. Linking and sequencing of PCR products generated the feoB region, which was 1.93 kb in size. The feoB gene sequences of H. pylori J99 and 26695 were compared with the clinical strains, and the sequences of feoB regions in the IDA (+) and (–) groups were compared.Results.  Sequence analysis of the complete coding region of the feoB gene revealed 16 sites of polymorphism or mutation. Among these, three polymorphisms (E/T254A, I263V, and K511Q) were indigenous to the Korean clinical strains. Although statistically significant differences were observed at four sites (K127T, A273S/P, I438V and I441T) between IDA (+) and (–), the number of specimens was too low to assess the significance of the differences.Conclusion.  The four polymorphisms of the feoB gene observed appear to be related to the clinical phenotype of IDA, but the relation is unclear because of the small number of strains studied. Further studies are required to confirm a correlation between IDA and H. pylori infection.
Dual vs. Triple Therapy for Childhood Helicobacter pylori Gastritis: a Double‐Blind Randomized Multicentre Trial
Authors: Oderda Giuseppina , Marinello Daniela , Lerro Pietro , Kuvidi Maria , De’Angelis Gian Luigi , Ferzetti Anna , Cucchiara Salvatore , Franco Maria Teresa , Romano Claudio , Strisciuglio Pietro , Pensabene Lucia 
Published: July 2004

ABSTRACTBackground.  Data on the efficacy of eradication treatment for Helicobacter pylori gastritis in children are scarce.Aim.  To evaluate the efficacy of triple therapy with lansoprazole plus amoxicillin and tinidazole vs. dual therapy with amoxicillin and tinidazole in a double‐blind randomized multicentre trial, and the usefulness of eradication in terms of long‐term symptom resolution.Subjects.  We enrolled 43 consecutive children undergoing endoscopy for upper gastrointestinal dyspepsia with H. pylori gastritis. They underwent a 13C‐urea breath test, completed a 2‐week symptom diary card, and were randomized. Treatment was given in a Redidose box (Redidose Company Ltd., Brighton, UK) containing either lansoprazole‐amoxicillin‐tinidazole (triple therapy) or placebo plus amoxicillin‐tinidazole (dual therapy) for 1 week. The completion of a 2‐week symptom diary card and the performance of a breath test were repeated 6 weeks and 6 months after the end of therapy. One to two years later, a structured telephone interview was conducted with 36 of the children.Results.  According to the breath test, 6 weeks after the end of therapy H. pylori was eradicated in 15 of 22 children on triple therapy [68.2%; 95% confidence interval (CI) = 45–88] and in 15 of 21 children on dual therapy (71%; 95% CI = 48–89; not significant), and 6 months after the end of therapy it was eradicated in 16 of 22 children on triple therapy (72.7%) and in 15 of 21 children on dual therapy. Six months after therapy, symptoms were analysed in 11 H. pylori‐positive and 31 H. pylori‐negative children, and it was found that dyspeptic symptoms had disappeared or improved in both groups, with no difference between them. One to two years later, 36 children were interviewed. Epigastric pain had recurred in three of 26 H. pylori‐negative and in seven of 10 H. pylori‐positive children (p = .001); in three of the latter, pain was severe and required additional treatment.Conclusion.  One‐week triple or dual therapy with two antibiotics achieved similar eradication rates. Soon after treatment, symptoms disappeared or improved in most children irrespective of eradication, but epigastric pain recurred in the majority of the still‐infected children within 2 years.
The crystal structure of microtubule‐associated protein light chain 3, a mammalian homologue of Saccharomyces cerevisiae Atg8
Authors: Sugawara Kenji , Suzuki Nobuo N. , Fujioka Yuko , Mizushima Noboru , Ohsumi Yoshinori , Inagaki Fuyuhiko 
Published: July 2004

Microtubule‐associated protein light chain 3 (LC3), a mammalian homologue of yeast Atg8, plays an essential role in autophagy, which is involved in the bulk degradation of cytoplasmic components by the lysosomal system. Here, we report the crystal structure of LC3 at 2.05 Å resolution with an R‐factor of 21.8% and a free R‐factor of 24.9%. The structure of LC3, which is similar to those of Golgi‐associated ATPase enhancer of 16 kDa (GATE‐16) and GABAA receptor‐associated protein (GABARAP), contains a ubiquitin core with two α helices, α1 and α2, attached at its N‐terminus. Some common and distinct features are observed among these proteins, including the conservation of residues required to form an interaction among α1, α2 and the ubiquitin core. However, the electrostatic potential surfaces of these helices differ, implicating particular roles to select specific binding partners. Hydrophobic patches on the ubiquitin core of LC3, GABARAP and GATE‐16 are well conserved and are similar to the E1 binding surface of ubiquitin and NEDD8. Therefore, we propose that the hydrophobic patch is a binding surface for mammalian Atg7 similar to a ubiquitin‐like conjugation system. We also propose the functional implications of the ubiquitin fold as a recognition module of target proteins.
Transcriptional responses to epigallocatechin‐3 gallate in HT 29 colon carcinoma spheroids
Authors: McLoughlin Patricia , Roengvoraphoj Monic , Gissel Cornelia , Hescheler Jürgen , Certa Ulrich , Sachinidis Agapios 
Published: July 2004

Catechins have been reported to possess anti‐cancer activity in vitro and in vivo. To identify target genes that may be involved in the anti‐tumorigenic effect of catechins, gene expression profiles in adherent human HT 29 colon carcinoma cells, in HT 29 spheroids and in epigallocatechin‐3 gallate (EGCG)‐treated HT 29 cells have been analysed by high‐density oligonucleotide microarrays. Treatment of HT 29 cells with EGCG (2.5–50 µm) resulted in a dose‐dependent inhibition of spheroid formation of HT 29 cells. Forty transcripts were induced at least twofold in 3‐day‐old spheroids relative to normal adherent cells using three replicates. Oncogenes like c‐fos and c‐jun are significantly up‐regulated in spheroids. We identified several signal transduction and proliferation genes which are down‐regulated in response to EGCG treatment. Increase in the mRNA expression profile of c‐Fos correlated well with protein levels in HT 29 spheroids whereas EGCG did not affect protein formation. In agreement with the DNA chip data, IQGAP2 protein was not increased in spheroids but protein formation was totally blocked in EGCG‐treated cells. Interestingly, no change in expression of cytotoxic or apoptotic related genes has been observed in EGCG‐treated cells. Our findings suggest that EGCG may exert its anti‐cancer activity through modulation of expression of a number of genes that are involved in cell proliferation, cell‐cell contacts and cell‐matrix interactions.
Do smokers know how to quit? Knowledge and perceived effectiveness of cessation assistance as predictors of cessation behaviour
Authors: Hammond D. , McDonald P. W. , Fong G. T. , Borland R. 
Published: July 2004

ABSTRACTAims  Despite the existence of effective cessation methods, the vast majority of smokers attempt to quit on their own. To date, there is little evidence to explain the low adoption rates for effective forms of cessation assistance, including pharmaceutical aids. This study sought to assess smokers’ awareness and perceived effectiveness of cessation methods and to examine the relationship of this knowledge to cessation behaviour.Design  A random‐digit‐dial telephone survey (response rate = 76%) with 3‐month follow‐up was conducted with 616 adult daily smokers in South‐Western Ontario, Canada.Measurements  A baseline survey assessed smoking behaviour, as well as smokers’ awareness and perceived effectiveness of cessation assistance. A follow‐up survey measured changes in smoking behaviour and adoption of cessation assistance at 3 months.Findings  Participants demonstrated a poor recall of cessation methods: 45% of participants did not recall nicotine gum, 33% did not recall the nicotine patch and 57% did not recall bupropion. Also, many participants did not believe that the following cessation methods would increase their likelihood of quitting: nicotine replacement therapies (36%), bupropion (35%), counselling from a health professional (66%) and group counselling/quit programmes (50%). In addition, 78% of smokers indicated that they were just as likely to quit on their own as they were with assistance. Most important, participants who perceived cessation methods to be effective at baseline, were more likely to intend to quit (OR = 1.80, 95% CI: 1.12–2.90), make a quit attempt at follow‐up (OR = 1.80, 95% CI: 1.03–3.16) and to adopt cessation assistance when doing so (OR = 3.62, 95% CI: 1.04–12.58).Conclusions  This research suggests that many smokers may be unaware of effective cessation methods and most underestimate their benefit. Further, this lack of knowledge may represent a significant barrier to treatment adoption.
Prevalence of non‐medical drug use and dependence among homosexually active men and women in the US population
Authors: Cochran Susan D. , Ackerman Deborah , Mays Vickie M. , Ross Michael W. 
Published: July 2004

ABSTRACTAims The aim of this study was to compare patterns of drug use and dependence between homosexually experienced and exclusively heterosexually experienced individuals.Design We used a cross‐sectional national household interview survey conducted in the United States.Setting Secondary data analysis of the 1996 National Household Survey on Drug Abuse was employed.Participants Participants were sexually active individuals, aged 18 years and older, who reported the genders of their sexual partners in the past 12 months; included 174 homosexually experienced (98 men, 96 women) and 9714 exclusively heterosexually experienced (3922 men, 5792 women) respondents.Measurements Life‐time, past 30 days and daily use of nine classes of drugs. Symptoms of dysfunctional use and dependence.Findings There were consistent patterns of elevated drug use in homosexually experienced individuals for life‐time drug use, but these were greatly attenuated for recent use. Homosexually experienced men were more likely to report use of marijuana, cocaine and heroin, and homosexually experienced women more likely to report use of marijuana and analgesics than individuals reporting only opposite‐sex partners. Both homosexually active men and women were more likely than exclusively heterosexually active respondents to report at least one symptom indicating dysfunctional drug use across all drug classes, and to meet criteria for marijuana dependence syndrome. The only difference between homosexually experienced men and women was that men were more likely to report any daily drug use.Conclusions These data are consistent with surveys suggesting that there is a moderate elevation of drug, particularly marijuana, use and dependence in gay and bisexual men and women when compared to heterosexual men and women.
The effect of matching comprehensive services to patients’ needs on drug use improvement in addiction treatment
Authors: Friedmann Peter D. , Hendrickson James C. , Gerstein Dean R. , Zhang Zhiwei 
Published: July 2004

ABSTRACTAims  To examine whether need–service matching in addiction treatment leads to improvements in drug use, and whether treatment duration mediates those improvements.Design, participants, measurements  This analysis utilizes prospective data from a US cohort of addiction treatment patients who reported service needs beyond core rehabilitative services (n = 3103). ‘Drug use improvement’ is the difference between the patient's peak drug use frequency (in days per month) in the year before intake and in the year after treatment. Overall and primary use of the major illicit drugs (heroin, powder or crack cocaine and marijuana) are considered separately. ‘Need–service match’ means that a patient rated a service as important at intake and reported its receipt during treatment. ‘Percentage of needs matched’ indicates the proportion of five service domains (medical, mental health, family, vocational and housing) so matched.Findings  In mixed regression models controlling for multiple factors, a greater percentage of needs matched tended to improve primary (β = 0.028, P = 0.09) and overall (β = 0.049, P = 0.05) drug use in the follow‐up year. Exclusion of treatment duration as a covariate doubled the magnitude of these coefficients. The benefits of matching were concentrated among the half of patients reporting needs in four to five rather than one to three domains, and were strongest among patients in long‐term residential facilities. Addressing vocational and housing needs exerted the greatest effects.Conclusions  Matching comprehensive services to needs is a useful addiction treatment practice, especially for high‐need patients. Treatment duration might partially mediate its effect.
Mortality risk among new onset injection drug users
Authors: Vlahov David , Wang Cun‐lin , Galai Noya , Bareta Joseph , Mehta Shruti H. , Strathdee Steffanie A. , Nelson Kenrad E. 
Published: July 2004

ABSTRACTAims  To characterize mortality experience among those who only recently started injection.Design  Prospective study.Setting  Independent study clinic within high drug use neighborhoods.Participants  In 1988–1989, we enrolled 256 adult injection drug users (IDUs) recruited through street outreach who had initiated injection within the prior 2 years.Measurements  Consenting participants underwent venipuncture for HIV antibody testing and interviews. We prospectively ascertained date and cause of death through follow‐up contact and registry linkages. Analyses included standardized mortality ratios (SMRs) with local, state and national mortality data, adjusted for age, gender and race.Findings  Baseline median age was 30 years, 70% were male, 95% were African‐American and 90% injected within the prior 6 months. We identified 69 deaths through October 2000; mortality rate was 3.3/100 person‐years. The adjusted SMR with the USA (and Baltimore) as the reference for IDUs was 4.40 (2.43) for 1991–1992, which increased to 8.12 (4.13) by 1993–1994, decreased to 4.43 (2.13) by 1997–1998 and increased slightly to 5.35 (2.79) during 1999–2000. Excluding HIV‐related mortality, SMRs remained elevated. Decline in SMRs was not linked to drug abuse treatment.Conclusions  These data demonstrate excess mortality among new‐onset IDUs compared with demographically similar peers in the general population, indicating the need for interventions to prevent premature death among young IDUs.