bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methodology and Transport Medium for Collection of Helicobacter pylori on a String Test in Remote Locations
Authors: Windsor Helen M. , Abioye‐Kuteyi Emmanuel A. , Marshall Barry J. 
Published: November 2005

ABSTRACTBackground.  Helicobacter pylori can be isolated from patients using the string test but contaminating oral and nasopharyngeal microflora need to be suppressed by rapid plating out onto selective culture media. Recently, use of this diagnostic method was enhanced by using a novel transport medium to collect specimens from subjects in a remote Australian clinic over 1300 km from the laboratory.Methods.  Retrieved string tests were transported to the laboratory in chilled polystyrene boxes in 5 ml screw‐cap bottles with 3 ml of a brain heart infusion broth plus antibiotics. These were 20 g/ml vancomycin, 10 g/ml trimethoprim, 10 g/ml cefsulodin, and 10 g/ml amphotericin B. A comparison was made between subjects who gargled with a chlorhexidine mouthwash before swallowing the string test and those who did not.Results.  Forty‐five urea breath test‐positive subjects were tested and H. pylori was isolated from 34 of them. Successful culture was achieved from string tests that were in transit for up to 29 hours and where the maximum temperature in the transport box was 14 °C. The additional use of a mouthwash had a marked effect on the isolation rate. H. pylori was cultured from 75% of subjects who gargled but only from 39% who did not.Conclusions.  This methodology and transport medium can broaden the use of the string test to more remote geographic areas where endoscopy is not feasible so that H. pylori isolates may still be obtained for diagnostic and epidemiologic studies. The value of this promising methodology of collection and transport should be assessed in a controlled study.
Major Influence of Oxygen Supply on 13CO2 : 12CO2 Ratio Measurement by Nondispersive Isotope‐Selective Infrared Spectroscopy
Authors: Riecke Björn , Neuhaus Peter , Stockmann Martin 
Published: November 2005

ABSTRACTBackground.  The nondispersive isotope‐selective infrared spectroscopy (NDIRS) is a valid method for the measurement of the 13CO2 : 12CO2 ratio in breath samples. Methodical influences have to be considered to obtain valid results.Aim.  To evaluate the effect of oxygen supply to patients on the measurement of 13C : 12C ratio in breath samples by NDIRS.Methods.  Breath samples of 26 healthy volunteers were taken before, immediately after, and 5 minutes after inhalation of 100% oxygen via a continuous positive air pressure (CPAP) mask. Analysis of breath samples was performed by NDIRS.Results.  Delta ‰ before oxygen inhalation was −25.8 ± 0.2. Immediately after 5 minutes of 100% oxygen inhalation, delta ‰ increased to −14.8 ± 0.5 (delta over baseline [DOB] 11.0 ± 0.4) and after additional 5 minutes of room air inhalation, delta ‰ normalized to −25.6 ± 0.2 (DOB 0.2 ± 0.1).Conclusions.  Oxygen supply to patients and, therefore, changes in gas composition in breath samples clearly influence 13CO2 measurement by NDIRS. This has to be taken into account in the clinical setting. Thus, oxygen supply during measurement of exhaled 13CO2 by NDIRS has to be avoided or maintained at a strictly constant level.
13C‐Urea Breath Test to Assess Helicobacter pylori Bacterial Load
Authors: Zagari Rocco Maurizio , Pozzato Paolo , Martuzzi Cristina , Fuccio Lorenzo , Martinelli Giuseppe , Roda Enrico , Bazzoli Franco 
Published: November 2005

ABSTRACTBackground.  Some authors have reported, using different protocols, that 13C‐urea breath test (13C‐UBT) is capable of assessing the intragastric Helicobacter pylori bacterial load, whereas others have not confirmed these data. Our aim is to evaluate the correlation between 13C‐UBT values and H. pylori bacterial load.Materials and Methods.  One hundred ninety‐two patients diagnosed H. pylori‐positive by rapid urease test, histology, and 13C‐UBT were enrolled. H. pylori bacterial load (H. pylori score) and gastritis activity (activity score) were evaluated according to the Updated Sydney System. 13C‐UBT was performed according to the European Standard Protocol. Breath samples were obtained every 10 minutes for 60 minutes in 52 patients and at 30 minutes (T30) in 140 patients and analyzed by mass spectrometry.Results.  At T30, mean ± SD excess delta 13CO2 excretion was 17.4 ± 1.1, 29.9 ± 2.2, and 48.7 ± 4.8 in patients with H. pylori scores 1, 2, and 3, respectively. This difference was statistically significant: H. pylori score 1 versus 2, p < .005; score 1 versus 3, p < .05; score 2 versus 3, p < .05. A significant positive correlation (G = 0.59) was found between H. pylori score and activity score of chronic gastritis. At T40 and T50 significant correlation between mean excess delta 13CO2 excretion and bacterial load was achieved only in patients with H. pylori scores 1 and 3.Conclusions.  13C‐UBT European Standard Protocol values correlate with H. pylori bacterial load and the activity of gastritis at T30 breath sampling time.
Asymptomatic Helicobacter pylori Infection Increases Asymmetric Dimethylarginine Levels in Healthy Subjects
Authors: Marra Maurizio , Bonfigli Anna Rita , Bonazzi Patrizia , Galeazzi Renato , Sirolla Cristina , Testa Ivano , Cenerelli Stefano , Boemi Massimo , Testa Roberto 
Published: November 2005

ABSTRACTBackground.  Chronic infections have been demonstrated to be early factors of atherosclerosis and cardiovascular diseases, and their relevance increases when they are caused by agents with extremely broad spectrum of disease outcome such as Helicobacter pylori. The consequent endothelial impairment leads to a reduced bioavailability of nitric oxide. Increasing evidences have pointed out that the endogenous inhibitor of nitric oxide synthase, asymmetric dimethylarginine, defined as a risk factor for cardiovascular disease, may increase in infections and plays an important role impairing the vascular functions of the endothelium. Starting from these findings, we aim to investigate whether H. pylori may affect asymmetric dimethylarginine levels.Materials and Methods.  The study was carried out on a group of 186 subjects (age 46.2 ± 14.9 years). We evaluated asymmetric dimethylarginine, symmetric dimethylarginine, L‐arginine, presence of H. pylori by 13C‐urea breath test, and the main parameters of glyco and lipo metabolic balance.Results.  Increased levels of asymmetric dimethylarginine were found in H. pylori‐positive subjects with respect to H. pylori‐negative subjects (0.46 ×/÷ 1.13 versus 0.42 ×/÷ 1.23 mol/l, p < .001, respectively). No differences were detected in L‐arginine levels between the two groups. Multiple regression analysis performed in H. pylori‐positive subjects and H. pylori‐negative subjects showed profound differences in the variables related to asymmetric dimethylarginine (R2 = 66.9%, p < .01 versus 34.3%, p < .01, respectively) and symmetric dimethylarginine (R2 = 39.2%, p < .01 versus 20.6%, p = .09, respectively) levels.Conclusions.  Our data clearly demonstrate that H. pylori infection increases asymmetric dimethylarginine levels. Moreover, this infection causes a profound metabolic modification that alters the role of the known determinants of asymmetric dimethylarginine levels. We conclude that H. pylori infection must be taken into account as a cause of increased asymmetric dimethylarginine levels and that the eradication of H. pylori may therefore lead to a decrease in asymmetric dimethylarginine levels, which is a further reason for the reduction of the risk for cardiovascular disease in this large portion of population.
Multiple Displacement Amplification of Isolated DNA from Human Gallstones: Molecular Identification of Helicobacter DNA by Means of 16S rDNA‐Based Pyrosequencing Analysis
Authors: Nilsson Isabelle , Shabo Ivan , Svanvik Joar , Monstein Hans‐Jürg 
Published: November 2005

ABSTRACTBackground.  Molecular typing of Helicobacter spp. in clinical biopsy specimens has become increasingly important. By means of nested polymerase chain reaction (PCR) amplification and Southern blot analysis of the PCR amplicons, we have shown that Helicobacter spp. DNA is present in human gallstones. In this study we have investigated the possibility of using multiple displacement amplification (MDA) of isolated gallstone DNA and pyrosequencing analysis for the molecular identification of Helicobacter spp.Materials and Methods.  DNA isolated from the nucleus of 33 human gallstones and one control strain were used in a MDA assay. Subsequently, pyrosequencing analysis was performed either directly on MDA‐DNA using primers flanking the Helicobacter spp. 16S rDNA variable V3 region or on PCR amplicons derived from broad‐range primers flanking the 16S rDNA variable V3, V4, and V9 regions.Results.  Pyrosequencing analysis of 16S rDNA derived from MDA‐DNA revealed that Helicobacter spp.‐like DNA was present in 25 of 33 (approximately 76%) gallstones. Using an H. pylori‐specific Southern blot analysis, Helicobacter spp.‐like DNA was present in 20 of 33 [approximately 61%] of the gallstones. Using MDA‐DNA directly in pyrosequencing analysis, Helicobacter spp.‐like DNA was present in 13 of 33 [approximately 39%] gallstones.Conclusions.  We conclude that multiple displacement amplification combined with pyrosequencing enables a rapid and accurate molecular typing of Helicobacter spp. from small and precious biopsy specimens.
Lower Prevalence of Helicobacter pylori Infection with vacAs1a, cagA‐Positive, and babA2‐Positive Genotype in Erosive Reflux Esophagitis Disease
Authors: Lai Chih‐Ho , Poon Sek‐Kwong , Chen Yun‐Chu , Chang Chi‐Sen , Wang Wen‐Ching 
Published: November 2005

ABSTRACTBackground.  Increased prevalence of esophagitis has been recognized in the West. Helicobacter pylori infection, particularly virulent strains, is proposed as a protective factor against the development of gastroesophageal reflux disease. To evaluate the relationship of reflux esophagitis with virulent H. pylori infection, we studied the prevalence of reflux esophagitis among H. pylori‐infected and ‐uninfected patients and the genotype of isolates in Taiwan.Methods.  Patients who had routine physical examination were investigated. The severity of esophagitis was evaluated using the Los Angeles grading system. H. pylori status was assessed by histology, rapid urease test, and bacterial culture. Genotyping of vacA, cagA, and babA2 was determined by polymerase chain reaction (PCR). Risk factors for severe esophagitis were evaluated.Results.  Reflux esophagitis was found in 21.2% of 1622 patients. The prevalence of H. pylori infection was found in 33.0% of 276 patients with reflux esophagitis compared with 67.5% of 378 patients with normal esophagus (p < .001). Esophagitis occurred in a significantly lower rate among H. pylori‐positive patients with peptic ulcer than those without peptic ulcer. cagA, babA2, and vacAs1a were detected in 100% of 143 isolates. Factors that predicted severe esophagitis included age, gender, and hiatus hernia but not H. pylori infection.Conclusions.  Our study suggests significantly lower incidence of H. pylori infection with the triple‐positive virulent genotype in patients with reflux esophagitis in Taiwan.
A Novel Mechanism of Autolysis in Helicobacter pylori: Possible Involvement of Peptidergic Substances
Authors: Fujita Yukihiro , Yamaguchi Kosaku , Kamegaya Taichi , Sato Hiroko , Semura Kayoko , Mutoh Kenichiro , Kashimoto Takashige , Ohori Hitoshi , Mukai Takao 
Published: November 2005

ABSTRACTBackground.  Helicobacter pylori survival in a hostile acidic environment is known to be caused by its production of urease, which is not released by known secretion pathways. It has been proposed that H. pylori cells undergo spontaneous autolysis during cultivation and that urease becomes surface‐associated only concomitant with bacterial autolysis. The aim of this study was to elucidate mechanisms by which H. pylori cells undergo autolysis during cultivation.Materials and Methods.  Autolysis of H. pylori KZ109 cells was estimated by measuring the turbidity of the culture, by detection of cytoplasmic protein release into the culture supernatant and by scanning electron microscopic observation of H. pylori cells during cultivation. An autolysis‐inducing factor (AIF) was partially purified from the culture supernatant by a partition method using ethyl acetate.Results.  Bacterial turbidity of KZ109 cells was drastically decreased after late‐log phase accompanying release of urease and HspB into the extracellular space. Concomitantly, cell lytic activity was detected in the culture supernatant. Scanning electron microscopic observation suggested that partially purified AIF induced cell lysis. It was also shown that the AIF is different from other autolytic enzymes or substances so far reported.Conclusions.  This study demonstrated the presence of the peptidergic autolytic substances in the culture supernatant of H. pylori KZ109 cells. The results of this study should be useful for further studies aimed at elucidation of the strategy of survival of H. pylori in the gastric environment and elucidation of the mechanisms of pathogenesis induced by H. pylori.
Susceptibility to infections in elite athletes: the S‐curve
Authors: Malm C. 
Published: November 2005

The susceptibility to upper respiratory tract infections (URTIs) after physical exercise has been described with a J‐shaped curve, suggesting protection from infections with moderate exercise and increased risk for URTI's in elite athletes. Several factors such as time of inoculation, previous infections, pathogen exposure, other stressors than exercise etc. can influence infection outcome. Observed infections in athletes can, therefore, be either the result of increased susceptibility to a novel pathogen, or more severe symptoms of an already established infection. Moreover, the definitions of “strenuous” exercise and “elite” athletes are equivocal, making comparisons between studies difficult.Because absence of infections is inevitable to become and maintain status as an elite athlete, it is suggested that there is an S‐shaped relationship between exercise load and risk of infections. To become an elite athlete one has to possess state‐of‐the‐art physique, including an immune system able to withstand infections even during severe physiological and psychological stress.
Validation of a Monoclonal Antibody-Based Capture Enzyme-Linked Immunosorbent Assay for Detection of
Campylobacter fetus
Authors: Devenish J. , Brooks B. , Perry K. , Milnes D. , Burke T. , McCabe D. , Duff S. , Lutze-Wallace C. L. 
Published: November 2005

ABSTRACT

A monoclonal antibody (MAb)-based antigen capture enzyme-linked immunosorbent assay (ELISA) was compared with the routine culture methodology for the detection of
Campylobacter fetus
subspecies from bovine and ovine field samples inoculated into Clark's transport enrichment medium (TEM). The work was a collaboration between two different diagnostic laboratories, one in Canada and the other in England. In both labs, TEM samples were incubated for 4 days at 35°C and then tested by culture and ELISA. The ELISA consisted of initial screening with MAb M1825 against
C. fetus
subspecies core lipopolysaccharide (LPS). All samples positive on ELISA screening were then retested by ELISA with MAb M1825 and MAbs M1177, M1183, and M1194, which recognize serotype A- and/or serotype B-specific
C. fetus
subspecies LPS epitopes. The Canadian samples consisted of 1,060 preputial washings from 529 bulls, of which 18 were positive by both culture and ELISA and 1,042 were negative by both methods. The English samples consisted of 321 tissue specimens, mostly stomach contents and placentas, from 190 aborted ovine and bovine fetuses. A total of 262 samples were negative by culture and ELISA, 52 samples were positive by culture and ELISA, and 7 samples were culture negative but ELISA positive. The results for all 70 culture-positive isolates were confirmed by conventional biochemical methods as
C. fetus
subsp.
fetus
, with 39 presumptively identified by the ELISA as serotype A and 30 presumptively identified as serotype B and with one sample containing isolates presumptively identified as serotype A and serotype B. A receiver operating characteristic analysis of the combined ELISA data from both countries resulted in an area under the curve of 0.997, with a sensitivity of 100% and a specificity of 99.5% relative to the results of culture. The data confirm that this ELISA method can be used as an excellent test for the screening of field samples in TEM for the presence of
C. fetus
subspecies.
Alterations of Natural Killer Cell and T-Lymphocyte Counts in Adults Infected with Human Immunodeficiency Virus through Blood and Plasma Sold in the Past in China and in Whom Infection Has Progressed Slowly over a Long Period
Authors: Jiang Yongjun , Shang Hong , Zhang Zining , Diao Yingying , Dai Di , Geng Wenqing , Zhang Min , Han Xiaoxu , Wang Yanan , Liu Jing 
Published: November 2005

ABSTRACT

Natural killer (NK) cells, natural killer T (NKT) cells, and T lymphocytes were analyzed by using a flow cytometer in 225 human immunodeficiency virus (HIV)-positive individuals infected through the past sale of blood and plasma without receiving antiretroviral therapy in the People’s Republic of China. According to CD4 T-cell counts these HIV-infected adults were stratified into three groups: long-term slow progressors, HIV-infected subjects, and AIDS patients. NK cell counts in long-term slow progressors were higher compared to HIV infection and AIDS patients (
P
< 0.05) and lower compared to normal controls (
P
< 0.05), whereas NKT cell counts in slow progressors and the HIV infection group were not different from those of normal controls. NK cell counts in HIV-seropositive subjects were positively correlated with CD4 T-cell counts (
P
< 0.05), and NKT cell counts were positively correlated with CD4 T-cell and CD8 T-cell counts (
P
< 0.05). The CD8 T-cell counts were higher in slow progressors compared to those with HIV infection, AIDS patients, and normal controls. These results indicated that HIV infection causes alterations of NK cells and T cells in slow progressors, HIV-infected subjects, and AIDS patient groups, but no difference was found in NKT cell counts and percentages in slow progressors and the HIV-infected group compared to normal controls.
A Strain-Specific Antigen in JapaneseHelicobacter pyloriRecognized in Sera of Japanese Children
Authors: Okuda Masumi , Sugiyama Toshiro , Fukunaga Kenichi , Kondou Masaru , Miyashiro Eikichi , Nakazawa Teruko 
Published: November 2005

ABSTRACTAn enzyme immuno assay (EIA) test based on Japanese strain-derived high-molecular-weight cell-associated proteins (JHM-CAP) was evaluated by comparing with a previously developed EIA test based on a U.S. strain-derived high-molecular-weight cell-associated proteins (HM-CAP). Serum samples of 131 Japanese asymptomatic children (mean age, 5.5 years; range, 0 to 21 years) were tested that include 43 positive and 88 negative children as judged byHelicobacter pyloristool antigen test (HpSA test). Both tests showed comparable and reliable specificities, but the sensitivity of JHM-CAP EIA, at 93.0%, was much higher than that of HM-CAP EIA, at 67.4%. More false-negative results of HM-CAP were obtained in children under 10 years of age. Immunoblot analysis revealed that the JHM-CAP but not the HM-CAP preparation had a 100-kDa antigen recognized by JHM-CAP positive sera. It was concluded that JHM-CAP EIA is highly accurate for the serodiagnosis ofH. pyloriinfection in Japanese young children and that the high sensitivity of JHM-CAP EIA in contrast to HM-CAP EIA is due to the presence of a 100-kDa antigen in Japanese strains that may be recognized by the host immune system at an early stage of infection.
Xylitol Inhibits Inflammatory Cytokine Expression Induced by Lipopolysaccharide fromPorphyromonas gingivalis
Authors: Han Su-Ji , Jeong So-Yeon , Nam Yun-Ju , Yang Kyu-Ho , Lim Hoi-Soon , Chung Jin 
Published: November 2005

ABSTRACTPorphyromonas gingivalisis one of the suspected periodontopathic bacteria. The lipopolysaccharide (LPS) ofP. gingivalisis a key factor in the development of periodontitis. Inflammatory cytokines play important roles in the gingival tissue destruction that is a characteristic of periodontitis. Macrophages are prominent at chronic inflammatory sites and are considered to contribute to the pathogenesis of periodontitis. Xylitol stands out and is widely believed to possess anticaries properties. However, to date, little is known about the effect of xylitol on periodontitis. The aim of the present study was to determine tumor necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β) expression when RAW 264.7 cells were stimulated withP. gingivalisLPS (hereafter, LPS refers toP. gingivalisLPS unless stated otherwise) and the effect of xylitol on the LPS-induced TNF-α and IL-1β expression. The kinetics of TNF-α and IL-1β levels in culture supernatant after LPS treatment showed peak values at 1 h (TNF-α) and 2 to 4 h (IL-1β), respectively. NF-κB, a transcription factor, was also activated by LPS treatment. These cytokine expressions and NF-κB activation were suppressed by pretreatment with pyrrolidine dithiocarbamate (an inhibitor of NF-κB). Pretreatment with xylitol inhibited LPS-induced TNF-α and IL-1β gene expression and protein synthesis. LPS-induced mobilization of NF-κB was also inhibited by pretreatment with xylitol in a dose-dependent manner. Xylitol also showed inhibitory effect on the growth ofP. gingivalis.Taken together, these findings suggest that xylitol may have good clinical effect not only for caries but also for periodontitis by its inhibitory effect on the LPS-induced inflammatory cytokine expression.
Comparison of Lipopolysaccharide-Binding Functions of CD14 and MD-2
Authors: Koraha Jun , Tsuneyoshi Naoko , Kimoto Masao , Gauchat Jean-Francois , Nakatake Hiroshi , Fukudome Kenji 
Published: November 2005

ABSTRACTPrior to being recognized by the cell surface Toll-like receptor 4/MD-2 complex, lipopolysaccharide (LPS) in the bacterial outer membrane has to be processed by LPS-binding protein and CD14. CD14 forms a complex with monomeric LPS extracted by LPS-binding protein and transfers LPS to the cell surface signaling complex. In a previous study, we prepared a functional recombinant MD-2 using a bacterial expression system. We expressed the recombinant protein inEscherichia colias a fusion protein with thioredoxin and demonstrated specific binding to LPS. In this study, we prepared recombinant CD14 fusion proteins using the same approach. Specific binding of LPS was demonstrated with a recombinant protein containing 151 amino-terminal residues. The region contained a hydrophilic region and the first three leucine-rich repeats (LRRs). The LRRs appeared to contribute to the binding because removal of the region resulted in a reduction in the binding function. LPS binding to the recombinant MD-2 was resistant to detergents. On the other hand, the binding to CD14 was prevented in the presence of low concentrations of detergents. In the case of human MD-2, the secondary myristoyl chain of LPS added by LpxM was required for the binding. A nonpathogenic penta-acyl LPS mutant lacking the myristoyl chain did not bind to MD-2 but did so normally to CD14. The broader LPS-binding spectrum of CD14 may allow recognition of multiple pathogens, and the lower affinity for LPS binding of CD14 allows transmission of captured materials to MD-2.