scholarly journals H. pyloriVirulence Factors: Influence on Immune System and Pathology

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Behnam Kalali ◽  
Raquel Mejías-Luque ◽  
Anahita Javaheri ◽  
Markus Gerhard
Keyword(s):  
Virulence Factors ◽  
Hygiene Hypothesis ◽  
The Other ◽  
Bacterial Physiology ◽  
Ulcer Disease ◽  
Bacterial Agent ◽  
Microbiological Characteristics ◽  
Socioeconomic Issues ◽  
H Pylori ◽  
High Level

Helicobacter pyloriis the most widespread chronic bacterial agent in humans and is well recognized for its association with ulcer disease and gastric cancer, with both representing major global health and socioeconomic issues. Given the high level of adaptation and the coevolution of this bacterium with its human host, a thorough and multidirectional view of the specific microbiological characteristics of this infection as well as the host physiology is needed in order to develop novel means of prevention of therapy. This review aims to pinpoint some of these potentially important angles, which have to be considered mutually when studyingH. pylori’s pathogenicity. The host’s biological changes due to the virulence factors are a valuable pillar ofH. pyloriresearch as are the mechanisms by which bacteria provoke these changes. In this context, necessary adhesion molecules and significant virulence factors ofH. pyloriare discussed. Moreover, metabolism of the bacteria, one of the most important aspects for a better understanding of bacterial physiology and consequently possible therapeutic and prophylactic strategies, is addressed. On the other hand, we discuss the recent experimental proofs of the “hygiene hypothesis” in correlation withHelicobacter’s infection, which adds another aspect of complexity to this infection.

scholarly journals Virulence Factors of Helicobacter pylori: A Review

2014 ◽  
Vol 7 ◽  
pp. CGast.S13760 ◽  
Author(s):  
Bruna M. Roesler ◽  
Elizabeth M.A. Rabelo-Gonçalves ◽  
José M.R. Zeitune
Keyword(s):  
Helicobacter Pylori ◽  
Clinical Outcome ◽  
Virulence Factors ◽  
Ulcer Disease ◽  
Clinical Disorders ◽  
H Pylori ◽  
High Level ◽  
Upper Gastrointestinal ◽  
Host Characteristics

Helicobacter pylori is a spiral-shaped Gram-negative bacterium that colonizes the human stomach and can establish a long-term infection of the gastric mucosa, a condition that affects the relative risk of developing various clinical disorders of the upper gastrointestinal tract, such as chronic gastritis, peptic ulcer disease, mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric adenocarcinoma. H. pylori presents a high-level of genetic diversity, which can be an important factor in its adaptation to the host stomach and also for the clinical outcome of infection. There are important H. pylori virulence factors that, along with host characteristics and the external environment, have been associated with the different occurrences of diseases. This review is aimed to analyzing and summarizing the main of them and possible associations with the clinical outcome.

A review of the possible bacterial determinants of clinical outcome inHelicobacter pyloriinfection

1998 ◽  
Vol 44 (3) ◽  
pp. 201-210 ◽  
Author(s):  
Carlo A Fallone ◽  
Alan N Barkun ◽  
Markus U Göttke ◽  
Robin N Beech
Keyword(s):  
Helicobacter Pylori ◽  
Clinical Outcome ◽  
Virulence Factors ◽  
Bacterial Virulence ◽  
Disease Outcome ◽  
Future Research ◽  
Susceptible Host ◽  
Ulcer Disease ◽  
Increased Risk ◽  
H Pylori

Helicobacter pylori is present in 40-60% of the population and approximately 10-20% of these infected individuals suffer from a H. pylori associated disease such as peptic ulcer disease or gastric cancer. This article reviews the potential bacterial determinants responsible for and markers predictive of both the acquisition of H. pylori infection and subsequent clinical outcome; i.e., asymptomatic infection or disease. The acquisition of H. pylori infection depends on exposure (hence the increased risk in lower socioeconomic groups and developing nations) to viable bacteria with at least a functional urease gene in a susceptible host. Once infection occurs, bacterial virulence factors, including the vacuolating cytotoxin, and genes of the cag pathogenicity island, as well as nonbacterial factors may determine disease outcome. Future research is being directed at discovering other bacterial virulence factors responsible for the different clinical outcomes of H. pylori infection. This will be greatly enhanced by the recent release of the complete genome sequence of H. pylori. The determination of the relative importance of each of these recognized and other as yet unrecognized factors responsible for disease outcome will assist in the appropriate targeting of patients in the treatment of H. pylori infection.Key words: Helicobacter pylori, genetics, virulence, bacterial.

scholarly journals Molecular typing ofHelicobacter pyloriisolates from asymptomatic, ulcer and gastritis patients by urease gene polymorphism

1994 ◽  
Vol 112 (1) ◽  
pp. 151-160 ◽  
Author(s):  
M. Desai ◽  
D. Linton ◽  
R. J. Owen ◽  
J. Stanley
Keyword(s):  
Molecular Typing ◽  
The Other ◽  
Disease Symptoms ◽  
Restriction Fragments ◽  
Ulcer Disease ◽  
Urease Gene ◽  
Gastroduodenal Disease ◽  
H Pylori ◽  
Asymptomatic Individuals ◽  
Almost All

SummaryThe gastric-adapted bacteriumHelicobacter pyloriplays an important role in gastritis and ulcer disease, but no phenotypic typing scheme presently exists for this organism. With a view to the development of genotypic typing, we have compared isolates ofH. pylorifrom gastritis or ulcer patients with those from subjects exhibiting no disease. Variation was analysed at the urease genes,ureA andureCD, by employing PCR-generated probes in genomic Southern blot hybridizations. WhilstureA restriction fragments provided a fourfold subgrouping of strains,ureCD fragments were considerably more discriminatory. Twenty-four combinedureACD profiles were generated withHindIII, subdividing the 64 strains into 11 types and 13 single profiles. The most prevalent profile (UI) was found in 33% of strains, almost all from gastritis or ulcer patients. On the other hand strains isolated from asymptomatic individuals had the most diverseureACD profiles. A key finding from this set of isolates was that strains ofH. pyloriassociated with general gastroduodenal disease were genetically more homogeneous than strains carried by people without disease symptoms.

scholarly journals Formation of the phenotypic structure of Phytophthora infestans population in Poland during 1987-2001

2013 ◽  
Vol 55 (1) ◽  
pp. 389-400 ◽  
Author(s):  
Hanna Zarzycka ◽  
Sylwester Sobkowiak ◽  
Renata Lebecka ◽  
Beata Tatarowska
Keyword(s):  
Phytophthora Infestans ◽  
Virulence Factors ◽  
Mating Type ◽  
The Other ◽  
Mating Types ◽  
Polish Population ◽  
Other Hand ◽  
Sexual Recombination ◽  
Phenotypic Structure ◽  
High Level

The formation of phenotypic structure of <i>P.infestans</i> population in Poland was determined by analyzing 1603 isolates collected from 1987 to 2001. The race complexity, low at the beginning of experiment, has been increasing from year to year and reached in 2001 a high level 7,2 virulence factors per isolate. The single and less composed races dominating firstly in the population were replaced gradually by more composed races. The virulence factors 1, 2, 3, 4, 7 and 11 occurred most frequently, but factors 5 and 8 were noted sporadically. The A2 mating type was detected in 1988 at first and since that time its occurrence has been noted in Polish population each year. The oospores were formed in potato tissues. Race diversity, low at the beginning of the investigation, reached a peak in 1996-2001 . During 1987-1990 weakly and middly aggressive phenotypes dominated in Polish population. In the later period very aggressive isolates were more frequent. Phenotypic race similarity of <i>P.infestans</i> populations in 1987 and 2001 was very low. The race structure of 1987 population was totally different from the race structure of populations of the next years. It was probably due to migration of new pathotypes. On the other hand the variation in complexity, diversity and similarity of races, as well as in aggressiveness observed in later years of investigation can be caused by the presence of both mating types and sexual recombination.

scholarly journals The Association ofHelicobacter pyloriInfection and Nonsteroidal Anti-Inflammatory Drugs in Peptic Ulcer Disease

2006 ◽  
Vol 20 (4) ◽  
pp. 277-280 ◽  
Author(s):  
Juan Carlos Zapata-Colindres ◽  
Sergio Zepeda-Gómez ◽  
Aldo Montaño-Loza ◽  
Edgar Vázquez-Ballesteros ◽  
José de Jesús Villalobos ◽  
...  
Keyword(s):  
Peptic Ulcer ◽  
Peptic Ulcer Disease ◽  
Bleeding Peptic Ulcer ◽  
The Other ◽  
Ulcer Disease ◽  
Group 3 ◽  
Anti Inflammatory ◽  
Group 2 ◽  
H Pylori ◽  
Group 1

BACKGROUND AND AIM: Peptic ulcer disease (PUD) affects 10% of the world population.Helicobacter pyloriinfection and the use of a nonsteroidal anti-inflammatory drug (NSAID) are the principal factors associated with PUD. The aim of the present study was to evaluate a cohort of patients with PUD and determine the association betweenH pyloriinfection and NSAID use.PATIENTS AND METHODS: The medical charts of patients with endoscopic diagnosis of PUD were retrospectively reviewed from September 2002 to August 2003. Patients were divided into three groups according to ulcer etiology:H pyloriinfection (group 1); NSAID use (group 2); and combinedH pyloriinfection and NSAID use (group 3).RESULTS: One hundred two patients were evaluated: 36 men (35.3%) and 66 women (64.7%). Forty patients hadH pyloriinfection, 43 had used NSAIDs and 15 had combinedH pyloriinfection and NSAID use; four patients with ulcers secondary to malignancy were excluded. The frequency of women was significantly higher in group 2 (P=0.01). The mean age of patients in group 1 was significantly lower than in the other two groups (P=0.003). PUD developed earlier in group 3 than in group 2 (5.0±4.7 months versus 1.4±2.1 months, respectively, P=0.018). Thirty-two patients (32.7%) had bleeding peptic ulcer. Group 2 had a higher risk of bleeding peptic ulcer than the other two groups (P=0.001).CONCLUSIONS: The development of PUD was observed earlier in the combinedH pyloriand NSAID group than in patients with only NSAID use. This suggests a synergic effect between the two risks factors in the development of PUD.

Morphological changes of Helicobacter pylori caused in vitro by cytoprotective anti-ulcer drug, Sofalcone

1990 ◽  
Vol 48 (3) ◽  
pp. 620-621
Author(s):  
Isamu Kondo ◽  
Masashl Yamaguchi
Keyword(s):  
Helicobacter Pylori ◽  
Peptic Ulcer ◽  
Bactericidal Activity ◽  
Morphological Changes ◽  
Bacterial Activity ◽  
The Other ◽  
H2 Receptor Antagonists ◽  
Ulcer Disease ◽  
H Pylori

Since Helicobacter pylori has recently been regarded as a possible causative agent of a chronic gastritis and a peptic ulcer disease, the susceptibilities of this organism to anti-ulcer agents or antibiotics have attracted much interest of not only clinical docters but also medicobiologists.We have reported that Sofalcone, a cytoprotective anti-ulcer drug, has anti-bacterial and bactericidal activity as well as TDS (tripotassium dicitrats bithmuthate) and Clarithromycin (a derivative of erythromycin), but the other anti-ulcer drugs Including anti-acid or H2 receptor antagonists such as cimetidine could not show such bacterial activity as those shown by the sofalcone (SFC), TDB, and clarithromycin (CLM). It was also found that therewere distinct differences between the morphological damage of H. pylori caused by SFC and those caused by TDB and CLM.

scholarly journals The effectiveness of anti-helicobacter therapy in the treatment of chronic gastroduodenal pathology in children with different levels of compliance

2018 ◽  
Vol 9 (4) ◽  
pp. 81-86
Author(s):  
Andrew V. Nalyotov ◽  
Sergey V. Nalyotov ◽  
Anna S. Barinova ◽  
Oleg G. Gorshkov
Keyword(s):  
Interpersonal Relationships ◽  
Sick Child ◽  
Disease Treatment ◽  
Strict Adherence ◽  
Ulcer Disease ◽  
Compliance Training ◽  
Parental Compliance ◽  
H Pylori ◽  
High Level ◽  
Different Levels

At the present time, the therapy of most diseases requires special attention not only from the treating physician, but also from the patient. In turn, in the treatment of children, the monitoring of compliance with the treatment is carried out not by the patient, but by his parents who control the regimen of taking medications. The aim of the study was to determine the efficiency of traditional anti-H. pylori regimen in the treatment of chronic gastroduodenal pathology in children with various level of parental compliance. 80 children of school age suffering from peptic ulcer disease duodenal ulcer associated with H. pylori from families with different levels of parental compliance were examined. The traditional anti-H. pylori therapy scheme containing omeprazole, clarithromycin lasting 14 days was prescribed for all children with chronic gastroduodenal pathology. It is established that strict adherence to the regimen and duration of administration of prescribed drugs allows achieving a high level of eradication of H. pylori even with the use of the traditional anti-Helicobacter pylori. Conducting a “compliance training” before starting therapy is an important factor that increases the level of parental compliance in patients with inflammatory-destructive diseases of the stomach and duodenum. Establishment of interpersonal relationships in the “doctor-patient-parent” system, working with parents, aimed at explaining the essence of the disease, the consequences of the disease, treatment tactics are an important stage in the therapy of a sick child.

scholarly journals Riboregulation in the Major Gastric Pathogen Helicobacter pylori

2021 ◽  
Vol 12 ◽  
Author(s):  
Alejandro Tejada-Arranz ◽  
Hilde De Reuse
Keyword(s):  
Helicobacter Pylori ◽  
Virulence Factors ◽  
Antisense Rna ◽  
Small Rnas ◽  
Genetic Regulation ◽  
Type I ◽  
Control Of Gene Expression ◽  
Ulcer Disease ◽  
Interesting Study ◽  
H Pylori

Helicobacter pylori is a Gram-negative bacterial pathogen that colonizes the stomach of about half of the human population worldwide. Infection by H. pylori is generally acquired during childhood and this bacterium rapidly establishes a persistent colonization. H. pylori causes chronic gastritis that, in some cases, progresses into peptic ulcer disease or adenocarcinoma that is responsible for about 800,000 deaths in the world every year. H. pylori has evolved efficient adaptive strategies to colonize the stomach, a particularly hostile acidic environment. Few transcriptional regulators are encoded by the small H. pylori genome and post-transcriptional regulation has been proposed as a major level of control of gene expression in this pathogen. The transcriptome and transcription start sites (TSSs) of H. pylori strain 26695 have been defined at the genome level. This revealed the existence of a total of 1,907 TSSs among which more than 900 TSSs for non-coding RNAs (ncRNAs) including 60 validated small RNAs (sRNAs) and abundant anti-sense RNAs, few of which have been experimentally validated. An RNA degradosome was shown to play a central role in the control of mRNA and antisense RNA decay in H. pylori. Riboregulation, genetic regulation by RNA, has also been revealed and depends both on antisense RNAs and small RNAs. Known examples will be presented in this review. Antisense RNA regulation was reported for some virulence factors and for several type I toxin antitoxin systems, one of which controls the morphological transition of H. pylori spiral shape to round coccoids. Interestingly, the few documented cases of small RNA-based regulation suggest that their mechanisms do not follow the same rules that were well established in the model organism Escherichia coli. First, the genome of H. pylori encodes none of the two well-described RNA chaperones, Hfq and ProQ that are important for riboregulation in several organisms. Second, some of the reported small RNAs target, through “rheostat”-like mechanisms, repeat-rich stretches in the 5′-untranslated region of genes encoding important virulence factors. In conclusion, there are still many unanswered questions about the extent and underlying mechanisms of riboregulation in H. pylori but recent publications highlighted original mechanisms making this important pathogen an interesting study model.

Vacuoles Induced in Mammalian Cells by Helicobacter Cytotoxin are Acidic Organelles

1990 ◽  
Vol 48 (3) ◽  
pp. 168-169
Author(s):  
M. H. Chestnut ◽  
C. E. Catrenich
Keyword(s):  
Acridine Orange ◽  
Mammalian Cells ◽  
Laser Scanning ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Ulcer Disease ◽  
Gastroduodenal Disease ◽  
H Pylori

Helicobacter pylori is a non-invasive, Gram-negative spiral bacterium first identified in 1983, and subsequently implicated in the pathogenesis of gastroduodenal disease including gastritis and peptic ulcer disease. Cytotoxic activity, manifested by intracytoplasmic vacuolation of mammalian cells in vitro, was identified in 55% of H. pylori strains examined. The vacuoles increase in number and size during extended incubation, resulting in vacuolar and cellular degeneration after 24 h to 48 h. Vacuolation of gastric epithelial cells is also observed in vivo during infection by H. pylori. A high molecular weight, heat labile protein is believed to be responsible for vacuolation and to significantly contribute to the development of gastroduodenal disease in humans. The mechanism by which the cytotoxin exerts its effect is unknown, as is the intracellular origin of the vacuolar membrane and contents. Acridine orange is a membrane-permeant weak base that initially accumulates in low-pH compartments. We have used acridine orange accumulation in conjunction with confocal laser scanning microscopy of toxin-treated cells to begin probing the nature and origin of these vacuoles.

Ethics in the Judiciary System of Bangladesh

1970 ◽  
Vol 1 (2) ◽  
pp. 34-36
Author(s):  
Mehedi Imam
Keyword(s):  
Rule Of Law ◽  
Judicial Independence ◽  
Moral Values ◽  
The Other ◽  
Considerable Time ◽  
Ethical Knowledge ◽  
Judicial Practice ◽  
Independent Judiciary ◽  
Role Players ◽  
High Level

In Bangladesh, demand for judicial independence in practice has been a much debated issue and the demand is fulfilled but expectation of people is not only limited to have an independent judiciary but to have an impartial system and cadre of people, which will administer justice rationally being free from fear or force. The independence of judiciary and the impartial judicial practice are related concepts, one cannot sustain without the other and here existence as well as the need of practicing impartiality is well recognized. But the art of practicing impartiality does not develop overnight as it’s related to development of one’s attitude. It takes a considerable time resulting from understanding, appreciating and acknowledging the moral values, ethics and professional responsibility. The judiciary includes Judges, Advocates mostly who are expected to demonstrate a high level of moral values and impartiality towards people seeking justice and ‘rule of law’. This is true that bench officers and clerks are also part of the process to ensure rule of law with same level of participation by the law enforcing agencies such as police. However the paper includes only those who either join judiciary as Judge/Magistrate or Advocate to explore level and extent of ethical knowledge they receive being key role players of the system. DOI: http://dx.doi.org/10.3329/bioethics.v1i2.9628 Bangladesh Journal of Bioethics 2010; 1(2): 34-36

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