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1.  Egg yolk emulsion agar, a new medium for the cultivation of Helicobacter pylori. 
Journal of Clinical Microbiology  1991;29(4):819-821.
We developed a new agar, egg yolk emulsion (EYE) agar, for cultivation of Helicobacter pylori. EYE agar contains Columbia agar base (Oxoid), 10% EYE (Oxoid), 1% IsoVitaleX (BBL), and 40 mg of Triphenyleteraxolium chloride (Sigma) per liter. We compared EYE agar with the following agars: (i) brain heart infusion agar-7% horse blood-1% IsoVitaleX (GDW agar; C. S. Goodwin, E. D. Blincow, J. R. Warren, T. E. Waters, C. R. Sanderson, and L. Easton, J. Clin. Pathol. 38:1127-1131, 1985), (ii) brain heart infusion agar-10% horse serum-0.2% charcoal-1% yeast extract-40 mg of triphenyltetrazolium chloride per liter (GLU agar; Y. Glupczynski, M. Labbe, and F. Thiabaumont, p. 3-6, in F. Megraud and H. Lamouliatte, ed., Gastroduodenal Pathology and Campylobacter pylori, 1989), (iii) Columbia agar with 7% lysed horse blood (D&M agar; J. C. Dent and C. A. M. McNulty, Eur. J. Clin. Microbiol. Infect. Dis. 7:555-558, 1988), and (iv) brain heart infusion agar-10% EYE-1% IsoVitaleX (BHIE agar). H. pylori CFU counts, expressed as average percentages of maximum growth, were as follows: EYE agar, 96; GDW agar. 76; BHIE agar, 57; D&M agar, 52; and GLU agar, 23. Colony counts for EYE agar were significantly higher than for GDW agar (P = 0.027), BHIE agar (P = 0.005), D&M agar (P = 0.0001), and GLU agar (P less than 0.0001). EYE agar also had higher CFU counts than two commercial chocolate media; the EYE agar count was 80%, versus 33% for BBL chocolate medium and 63% for Remel chocolate medium.
PMCID: PMC269878  PMID: 1890184
2.  Helicobacter pylori infection in older people 
Since the discovery of Helicobacter pylori (H. pylori) infection as the major cause of gastroduodenal disorders three decades ago, H. pylori has been the focus of active research and debate in the scientific community. Its linkage to several diseases, such as peptic ulcer disease, gastritis and gastric malignancy is incontestable. In particular, it has been noticed that, as the aged population is increasing worldwide, older people are at increased risk of developing several gastroduodenal diseases and related complications. At the same time, gastric cancer is definitely more frequent in elderly than in adult and young people. In addition, it has been showed that peptic ulcer and related complications occur much more commonly in aged individuals than in young people, resulting in a significantly higher mortality. Although this infection plays a crucial role in gastrointestinal disorders affecting all age groups and in particular older people, only a few studies have been published regarding the latter. This article presents an overview of the epidemiology, diagnosis, clinical manifestations and therapy of H. pylori infection in elderly people.
PMCID: PMC4047322  PMID: 24914358
Elderly; Helicobacter pylori; Diagnosis; Clinical features; Treatment
3.  Novel Antigens of Helicobacter pylori Correspond to Ulcer-Related Antibody Pattern of Sera from Infected Patients 
Journal of Clinical Microbiology  2002;40(2):547-552.
Recently, we reported that the patterns of antibodies to Helicobacter pylori protein antigens in serum may be useful for screening patients at high risk for ulcers (P. Aucher et al., J. Clin. Microbiol. 36:931-936, 1998). Here we report the identification, by a combination of electrophoretic, immunochemical, and protein sequencing methods, of five antigens that correspond to this antibody pattern: groEL, catalase A, flagellin A, beta-ketoacyl-acyl carrier protein synthase I (β-ketoacyl-ACP S), and peptidyl prolyl cis-trans isomerase (PPiase). β-Ketoacyl-ACP S and PPiase are reported for the first time as antigens of diagnostic interest in infections by H. pylori. The antigenicity of the five antigens, together with those of CagA and VacA, was tested in an immunoblot assay with water-soluble protein extracts from two H. pylori pathogenic strains (HP 141 and ATCC 43579) and panels of sera from H. pylori-positive patients with gastroduodenal ulcers (GDU), nonulcer dyspepsia (NUD), as well as sera from H. pylori-negative healthy volunteers. For catalase A, groEL, and flagellin A antigens, no overall statistically important values were found making it possible to discriminate between patients with GDU and NUD. For both H. pylori strains, the mean performance indices (MPI) presenting percentages of correctly classified patients with GDU and NUD showed that the most significant antibody patterns were as follows: anti-VacA + anti-β-ketoacyl-ACP S (MPI = 76.1), anti-VacA + anti-PPiase (MPI = 71.8), and anti-CagA + anti-VacA + anti-β-ketoacyl-ACP S (MPI = 70.5). Antibody patterns detected with these antigen profiles may therefore be useful in developing a diagnostic test designed to predict the clinical severity of the H. pylori infection within the adult population of France.
PMCID: PMC153369  PMID: 11825970
4.  Discontinuation of Antihyperglycemic Therapy After AMI: Medical Necessity or Medical Error? 
From a national Medicare database, we recently reported that 1 in 8 older patients with diabetes (DM) was discharged (DC) off all anti-hyperglycemic medication (AHM) following acute myocardial infarction (AMI). This practice was associated with increased 1-yr mortality, but the reasons for stopping AHM were not known. We sought to determine whether such practice might be due to medical necessity (i.e., new contraindication) or oversight – in which case a quality improvement opportunity might exist.
We identified 327 DM patients hospitalized with AMI over a 1-yr period at an academic medical center and an affiliated community hospital. We conducted detailed chart reviews on the 217 patients with AMI as a principal diagnosis who were admitted on AHM (insulin, 81). 25 (11.5%) were DC off AHM, 24 (96%) of whom received some AHM in the hospital, mostly insulin sliding scale. One patient’s (4%) AHM was stopped due to a change in care goals, a second developed recurrent hypoglycemia, and a third had entirely normal in-hospital blood glucose (BG) after AHM discontinuation. We categorized the remaining 88% as being DC off AHM without justification. The demographic/clinical characteristics of those DC on vs. off AHM were similar, except for better left ventricular ejection fraction (LVEF) in the latter.
In this study, the proportion of DM patients DC off AHM following AMI was nearly identical to that in a national database (~1/8). We found no clear reason for this practice in nearly 90% of cases, suggesting that it may often constitute a medical error. Based on our prior finding of associated increased mortality, this may represent an opportunity to improve the care of the growing population of DM patients with ischemic heart disease.
PMCID: PMC3534988  PMID: 23002492
5.  Early-Life Family Structure and Microbially Induced Cancer Risk 
PLoS Medicine  2007;4(1):e7.
Cancer may follow exposure to an environmental agent after many decades. The bacterium Helicobacter pylori, known to be acquired early in life, increases risk for gastric adenocarcinoma, but other factors are also important. In this study, we considered whether early-life family structure affects the risk of later developing gastric cancer among H. pylori+ men.
Methods and Findings
We examined a long-term cohort of Japanese-American men followed for 28 y, and performed a nested case-control study among those carrying H. pylori or the subset carrying the most virulent cagA+ H. pylori strains to address whether family structure predicted cancer development. We found that among the men who were H. pylori+ and/or cagA+ (it is possible to be cagA+ and H. pylori− if the H. pylori test is falsely negative), belonging to a large sibship or higher birth order was associated with a significantly increased risk of developing gastric adenocarcinoma late in life. For those with cagA+ strains, the risk of developing gastric cancer was more than twice as high (odds ratio 2.2; 95% confidence interval 1.2–4.0) among those in a sibship of seven or more individuals than in a sibship of between one and three persons.
These results provide evidence that early-life social environment plays a significant role in risk of microbially induced malignancies expressing five to eight decades later, and these findings lead to new models to explain these interactions.
This study suggests that early-life social environment has a significant role in risk of microbially induced malignancies such as gastric adenocarcinoma occuring five to eight decades later.
Editors' Summary
Although the theory that certain cancers might be caused by infectious agents (such as bacteria and viruses) has been around for some time, concrete evidence linking specific cancers and infections is only recently beginning to emerge. There is now very good evidence that stomach cancer, once one of the frequent types worldwide but now less common, is strongly associated with a particular infection of the stomach lining. This specific bacterium colonizing the stomach, Helicobacter pylori (or H. pylori), often infects people early in childhood through close contact with other people, and tends to stay in the body throughout life. However, most people do not suffer any symptoms as a result of being colonized with H. pylori. Researchers are interested in the relationship between stomach cancer and aspects of someone's upbringing, for example whether an individual has a large number of sisters and brothers and whether they are the youngest or oldest in a large group of siblings. One reason for being interested in this topic is that if H. pylori is mainly spread from one child to another in the home, we might expect children from large sibling groups, and the youngest children in a group, to be at greater risk of being infected, and then more likely to get stomach cancer later in life. Furthermore—and this was the primary reason for the study—the researchers wished to determine whether, among H. pylori+ people, the structure of the family affects the risk of developing stomach cancer much later in life. With all study participants being H. pylori+, the essential comparison was between people of high and low birth order.
Why Was This Study Done?
This group of researchers had already done a previous study that had shown that people who carry H. pylori in their stomachs are more likely to get stomach cancer, and also that younger children in a sibling group are more likely to get stomach cancer. In the period following that study, the examined population has become older and more of the people concerned have developed stomach cancer. This meant that the researchers could go back and extend their previous work to see, more reliably, whether stomach cancer was linked to family structure. It also meant that the researchers could look at the effects of each factor not only in isolation, but also the combined effect of all the different factors. The researchers also stratified for the most virulent strains (those that were cagA+).
What Did the Researchers Do and Find?
In this study, the researchers started out with a pool of 7,429 Japanese-American men living in Hawaii, USA, who had donated blood samples between 1967 and 1975. Of these men, 261 eventually developed stomach cancer. Each of the 261 men was then matched with a similarly aged man from the original pool of 7,429 men who did not have stomach cancer. The researchers then went back to the original blood samples taken many years before and tested the samples to see if the men were infected with H. pylori at the time the sample was taken and, if so, whether a particular strain of the bacterium, cagA, was present. The researchers then looked at whether the risk of getting stomach cancer was associated with the number of siblings a man had and whether he was older or younger than the other siblings.
Similar to the prior study, they found that men who had stomach cancer were three times more likely to carry H. pylori compared to men who did not develop stomach cancer. In men who had H. pylori, those with large numbers of siblings were more likely to get stomach cancer, and this was especially true for men who had the cagA strain of H. pylori. In the whole group of men with cancer, the order of birth (whether a man was older or younger in his sibling group) did not seem to be particularly linked to development of stomach cancer. However, in men who had the cagA strain of H. pylori, those from the largest sibships were at highest risk of developing gastric cancer; in this group, one particular type of cancer (the most common type—intestinal-type gastric cancer) was also associated with later birth order.
What Do These Findings Mean?
The researchers initially thought that men with H. pylori would be at a higher risk of getting stomach cancer if they had a large number of sisters and brothers, and especially if they were a younger sibling in a large group. This idea was supported by their data. These findings support the idea that people often get H. pylori from their older sisters and brothers, but there is not conclusive proof of this. There might be some other factor that explains the association between large family size and stomach cancer, for example that people from large families might be poorer and more at risk from stomach cancer for some other reason. Currently, most doctors do not recommend routinely testing people without any symptoms to see if they have H. pylori, but people with pain or discomfort in the upper abdomen would generally be screened for H. pylori and then treated to eliminate the infection if it is found. The main novel idea is that those people who are born in a large sibship, and/or are of higher birth order, are more likely to acquire their H. pylori from a genetically related person (a sibling) than from an unrelated person (friend/classmate). This “family-structure effect” could be the explanation as to why there is a higher risk of stomach cancer developing later—the strain from a genetically related person already is “preadapted” to the new host, and has a “head-start” on immunity, compared to a strain from an unrelated person. The researchers hypothesize that it is the nature of that initial interaction with the host that sets the stage for the kind of events that lead to cancers decades later.
Additional Information.
Please access these Web sites via the online version of this summary at
A Perspective article by Dimitrios Trichopoulos and Pagona Lagiou discusses these findings further
MedLine Plus encyclopedia entry on stomach cancer
Wikipedia entry on Helicobacter pylori (Wikipedia is an internet encyclopedia that anyone can edit)
The US National Cancer Institute publishes information about stomach cancer
PMCID: PMC1769414  PMID: 17227131
6.  Helicobacter pylori in Iran: A systematic review on the association of genotypes and gastroduodenal diseases 
Helicobacter pylori (H. pylori) infection is known as a major etiologic factor for a variety of gastroduodenal diseases. In Iran, with a high rate of H. pylori infection close to 90%, numerous studies have revealed many aspects of interaction between the bacterium, mucosal surface and induction of disease outcome. The organism is genetically diverse and several virulence factors are attributed to the more virulent strains. The well-characterized virulence factors of H. pylori are cytotoxin associated gene A and vacuolating cytotoxin gene A. The distribution pattern of H. pylori genotypes and its association with disease status varies geographically. The present review focused on the virulence factors and genotyping of H. pylori in relation to gastroduodenal disorders in different regions of Iran.
In total, 398 studies were reported on different aspects related to H. pylori in our electronic search from 1995-2011. H. pylori infection and its virulence factors in association with disease status were investigated in 159 reports. Looking specifically at the gastrointestinal tract disorders, the most relevant reports including 37 papers were selected.
We found no correlation of cagA genotype and disease status in the majority of studies, whereas vacA was demonstrated as a useful marker in predicting the disease outcome. The results of reports on other virulence factors of H. pylori such as blood group antigen-binding adhesion gene A, the induced by contact with epithelium gene A, the outer inflammatory protein A, the duodenal ulcer promoting gene A, and Helicobacter outer membrane gene and their relation with disease status were contradictory.
Although different markers of H. pylori were emphasized as useful when predicting disease outcomes in some studies, the inconsistent researches and the scarcity of data made any conclusion or even comparison impossible. Considering the gap of information observed during our search relating to genotyping and other aspects of H. pylori infection, further investigations are suggested.
PMCID: PMC3527048  PMID: 23267382
H. pylori; Genotyping; Virulence; Gastroduodenal; cagA; vacA; Iran
7.  Recent advances in oesophageal diseases 
Dong Y, Qi B, Feng XY, Jiang CM. Meta-analysis of Barrett's esophagus in China. World J Gastroenterol 2013;19(46):8770-8779
The disease pattern of Barrett's esophagus (BE) in China is poorly characterised particularly in comparison with other developed countries. This meta-analysis of 3873 cases of BE collated from 69 clinical studies conducted in 25 provinces between 2000 and 2011 investigated the epidemiology and characteristics of BE in China compared to Western countries. The total endoscopic detection rate of BE was 1.0% (95%CI: 0.1%-1.8%) with an average patient age of 49.07 ± 5.09 years, lower than many Western countries.The authors postulate this may be attributed to environmental risk factor variation, distinct genetics and different medical practice including diagnostic criteria for BE and expertise in endoscopy. This study identified a 1.781 male predominancefor BE in China, consistent with Western reports. Short-segment BE accounted for 80.3% of cases with island type and cardiac type the most common endoscopic (44.8%) and histological (40.0%) manifestations respectively. Of the 1283 BE cases followed up for three to 36 months the incidence of esophageal cancer was 1.418 per 1000 person-years, lower than the incidence reported in Western countries.
Lee HS, Jeon SW. Barrett esophagus in Asia: same disease with different pattern. ClinEndosc 2014;47(1):15-22
Barrett's esophagus (BE) is a common, pre-cancerous condition characterised by intestinal metaplasia of squamous esophageal epithelium usually attributed to chronic gastric acid exposure. This review article explores important differences in the disease pattern of BE between Asian and the Western countries.
Overall the prevalence of BE is lower in Asia compared to the West with a greater proportion of short-segment type. The authors identify great variability in the endoscopic and pathologic diagnostic criteria for BE. Many of the studies in Asian countries did not use a standardised four-quadrant biopsy protocol which may have led to an underestimation of BE prevalence. The review highlights an increasing incidence of esophageal adenocarcinoma in the West but unclear disease trend in Asia with inter-country variability. Similarly in Asian and Western countries BE is associated with the presence of hiatus hernia, advancing age, male gender, alcohol consumption, smoking, abdominal obesity and longer duration of gastro-esophageal reflux disease. The authors postulate that Helicobacter pylori infection, more prevalent in Asia than the West, may have a protective effect on BE.
There is a need for larger, prospective studies to further clarify the disease pattern of BE in Asian countries. Clearly standardisation of the diagnostic process for BE is important to validate the differences in disease trends between Asian and Western countries.
Kiadaliri AA. Gender and social disparities in esophagus cancer incidence in Iran, 2003-2009: a time trend province-level study.Asian Pac J Cancer Prev 2014;15(2):623-7
Esophageal cancer (EC) is a major cause of morbidity and mortality particuarly in Iran where the incidence rate exceeds the global average. An understanding of the factors influencing the province-specific incidence of EC in Iran is important to inform disease-prevention strategies and address health inequalities. This ecological study used cancer registry data to investigate the relationship between gender and social class and the incidence of EC in Iran at province-level between 2003 and 2009. The age standardised incidence rates (ASIR) of EC were greatest in the Northern provinces of Iran, specifically Razavi Khorasan in males and Kordestan in females. Overall the EC incidence did not significantly differ according to gender.
Interestingly, during the study period the ASIR increased by 4.6% per year in females (p=0.08) and 6.5% per year in males (p=0.02). This may reflect increasing rates of establised risk factors for EC including obsesity and gastro-esophageal reflux disease alongside more vigilant recording of new cases. Social class was inversely associated with the ASIR of EC regardless of gender which may be attributed to class differences in risk factor distribution particularly smoking, diet and obesity. An appreciation for the limitations of an epidemiological study is important when interpreting results which should be further evaluated in future studies.
Islami F et al.Determinants of gastroesophageal reflux disease, including hookah smoking and opium use- A cross-sectional analysis of 50,000 individuals. PLoS One 2014;9(2):e89256
Gastroesophageal reflux disease (GERD) is a highly prevalent cause of gastrointestinal symptoms worldwide incurring great cost to the primary and secondary healthcare sectors. An improved understanding of the factors which influence GERD symptoms in low- to medium- income countries may inform public health initiatives. This study analysed prospective data from the Golestan cohort study, primarily established to investigate determinants of upper gastrointestinal cancers, toexplore the risk factors influencing GERD symptoms (regurgitation and/or heartburn) in 50,045 individuals aged 40-75 years in Golestan Province, Iran enrolled between 01/2004 and 06/2008.Of note, 39.12% of individuals denied ever experiencing GERD symptoms. A further 19.89% reported at least once weekly GERD symptoms with 11.83% experiencing daily symptoms. Severe symptoms, defined as disturbing daily work or sleep, were recorded by 11.33% of individuals.
Separately the occurrence of daily GERD symptoms and severe symptoms were inversely associated with male gender (OR 0.36, 95% CI 0.33-0.39 both), level of formal education (p=0.01 and p=0.001 respectively), wealth score (p<0.001 both) and regular nass chewing (OR 0.86, 95% CI 0.75-0.98 and OR 0.87, 95% CI 0.76-0.99 respectively)and were positively associated with body mass index (p<0.001 both), intensity of physical activity (p=0.04 both), cigarette pack years (p<0.001 both), alcohol consumption (OR 1.36, 95% CI 1.13-1.64 and OR 1.53, 95% CI 1.28-1.83 respectively) and opium use (OR 1.82, 95% CI 1.67-1.99 and OR 1.70, 95% CI 1.55-1.87 respectively).In addition hookah smoking had a borderline significant correlation with mild and moderate severity GERD symptoms in individuals who had never smoked cigarettes (OR 1.41, 95% CI 1.00-1.99 and OR 1.25, 95% CI 0.99-1.57 respectively).
Overall this large study contributes useful data to inform the prevention and management of GERD symptoms particularly regarding the use of hookah, opium and nass which was previously unclear.
Barbera M et al. The human squamous oesophagus has widespread capacity for clonal expansion from cells at diverse stages of differentiation. Gut 2014;0:1–9. doi:10.1136/gutjnl-2013-306171
Current knowledge on human esophageal tissue homeostasis and injury repair is derived predominantly from murine models and hence may be inaccurate due to cellular and architectural differences. This study used 3D imaging in conjunction withstaining for cell lineage markers to investigate the cellular mechanisms involved in homeostasis of the normal human squamous esophagus in 10 participants undergoing esophagectomy for esophageal cancer. The self-renewal potential of cell subpopulations was also assessed using in vitro and in vivo assays.
A decreasing gradient of cell proliferation was observed from the inter-papillary basal layer to the tip of the papilla where there was no evidence of mitosis. The expression ofβ1-integrin, a putative stem cell marker, was consistent throughout the basal layer and therefore the entire basal layer can be considered undifferentiated. Quiescent β1-integrin/CD34-positive cells which failed to stain for CD45, S-100 or F4-80were identified at the tip of the papilla suggesting this is an extension of the basal layer. Contrary to previous data, this study found progenitor cells widely distributed in human esophageal tissue and included already differentiated epithelial cells. This insight into esophageal homeostasis may inform future studies exploring the pathological mechanisms underpinning homeostatic disruption in disease states such as Barrett's esophagus.
Papers were prepared by:
Drs Ishfaq Ahmad and Luke Materacki, Department of Medicine, Alexandra Hospital, Redditch, UK
PMCID: PMC4129572  PMID: 25120902
8.  The significance of virulence factors in Helicobacter pylori 
Journal of digestive diseases  2013;14(7):341-349.
Helicobacter pylori (H. pylori) infection is linked to various gastroduodenal diseases; however, only a small fraction of these patients develop associated diseases. Despite the high prevalence of H. pylori infection in Africa and South Asia, the incidence of gastric cancer in these areas is much lower than those in other countries. The incidence of gastric cancer tends to decrease from north to south in East Asia. Such geographic differences in the pathology can be explained, at least in part, by the presence of different types of H. pylori virulence factors in addition to the host and environmental factors. Virulence factors of H. pylori, such as cagA, vacA, dupA, iceA, oipA and babA, have been demonstrated to be predictors of severe clinical outcomes. Interestingly, meta-analysis showed that CagA seropositivity was associated with gastric cancer compared with gastritis even in East Asian countries where almost of the strains possessing cagA. Meta-analysis also confirmed the significance of vacA, dupA and iceA. However, there remains the possibility that additional important pathogenic genes can be existed because H. pylori consists of approximately 1 600 genes. Despite advances in our understanding of the development of H. pylori-related diseases, further work is required to clarify the roles of H. pylori virulence factors.
PMCID: PMC3721066  PMID: 23452293
Helicobacter pylori; virulence factors; stomach neoplasms
9.  A Comprehensive Sequence and Disease Correlation Analyses for the C-Terminal Region of CagA Protein of Helicobacter pylori 
PLoS ONE  2009;4(11):e7736.
Chronic Helicobacter pylori infection is known to be associated with the development of peptic ulcer, gastric cancer and gastric lymphoma. Currently, the bacterial factors of H. pylori are reported to be important in the development of gastroduodenal diseases. CagA protein, encoded by the cagA, is the best studied virulence factor of H. pylori. The pathogenic CagA protein contains a highly polymorphic Glu-Pro-Ile-Tyr-Ala (EPIYA) repeat region in the C-terminal. This repeat region is reported to be involved in the pathogenesis of gastroduodenal diseases. The segments containing EPIYA motifs have been designated as segments A, B, C, and D; however the classification and disease relation are still unclear. This study used 560 unique CagA sequences containing 1,796 EPIYA motifs collected from public resources, including 274 Western and 286 East Asian strains with clinical data obtained from 433 entries. Fifteen types of EPIYA or EPIYA-like sequences are defined. In addition to four previously reported major segment types, several minor segment types (e.g., segment B′, B′′) and more than 30 sequence types (e.g., ABC, ABD) were defined using our classification method. We confirm that the sequences from Western and East Asian strains contain segment C and D, respectively. We also confirm that strains with two EPIYA segment C have a greater chance of developing gastric cancer than those with one segment C. Our results shed light on the relationships between the types of CagAs, the country of origin of each sequence type, and the frequency of gastric disease.
PMCID: PMC2768901  PMID: 19893742
10.  The significance of cagA+Helicobacter pylori in reflux oesophagitis 
Gut  2001;49(3):341-346.
BACKGROUND—Helicobacter pylori is a gastroduodenal pathogen associated with ulceration, dyspepsia, and adenocarcinoma. Recent preliminary studies have suggested that H pylori may be protective for oesophageal adenocarcinoma. In addition, strains of H pylori identified by the presence of the cytotoxin associated gene A (cagA) are shown to have a significant inverse association with oesophageal adenocarcinoma. Given that cagA+ H pylori may protect against oesophageal carcinoma, these strains may be protective for oesophagitis, a precursor of oesophageal carcinoma.
AIMS—The aim of this study was to investigate the association between cagA+ H pylori and endoscopically proved oesophagitis.
PATIENTS—The study group included 1486 patients attending for routine upper gastrointestinal tract endoscopy.
METHODS—At endoscopy the oesophagus was assessed for evidence of reflux disease and graded according to standard protocols. Culture and histology of gastric biopsy specimens determined H pylori status. The prevalence of cagA was identified by an antibody specific ELISA (Viva Diagnostika, Germany).
RESULTS—H pylori was present in 663/1485 (45%) patients and in 120/312 (38%) patients with oesophagitis. Anti-CagA antibody was found in 499/640 (78%) H pylori positive patients. Similarly, anti-CagA antibody was found in 422/521 (81%) patients with a normal oesophagus and in 42/60 (70%) with mild, 24/35 (69%) with moderate, and 11/24 (46%) with severe oesophagitis. The risk of severe oesophagitis was significantly decreased for patients infected with cagA+ H pylori after correction for confounding variables (odds ratio 0.57, 95% confidence interval 0.41-0.80; p=0.001).
CONCLUSIONS—These results suggest that infection by cagA+ H pylori may be protective for oesophageal disease.

Keywords: Helicobacter pylori; cagA+; gastro-oesophageal reflux disease; oesophagitis; oesophageal adenocarcinoma; hiatus hernia
PMCID: PMC1728436  PMID: 11511554
11.  Major virulence factors, VacA and CagA, are commonly positive in Helicobacter pylori isolates in Japan 
Gut  1998;42(3):338-343.
Background—VacA and CagA proteins have been reported to be major virulence factors of Helicobacter pylori. However, antibodies against these proteins are frequently found in the sera of Japanese patients regardless of their gastroduodenal status. 
Aim—To evaluate the expression of VacA and CagA proteins by H pylori strains isolated in Japan. 
Methods—By using specific antibodies raised against recombinant VacA and CagA proteins, the expression of VacA and CagA was evaluated in 68 H pylori strains isolated from Japanese patients; a vacuolating assay and genotyping of the vacA gene were also used in the evaluation. The results were analysed in relation to the gastroduodenal diseases of the hosts. 
Results—VacA and CagA proteins were expressed in 59/68 (87%) and in 61/68 (90%) isolates respectively. The vacuolating assay was positive in 57/68 (84%) isolates, indicating that most immunologically VacA positive strains produced active cytotoxin. The prevalence of infection with strains expressing CagA and positive for vacuolating activity (Type I) was very high, 54/68 (79%), irrespective of the gastroduodenal status of the host. 
Conclusion—Most H pylori isolates in Japan are positive for vacuolating cytotoxin and CagA, and thus these virulence factors cannot be used as markers to discern the risk of developing serious gastroduodenal pathologies in the hosts. However, the high prevalence of infection with strains positive for vacuolating cytotoxin and CagA may contribute to the characteristics of H pylori infection in Japan. 

Keywords: VacA; Helicobacter pylori; CagA; ulcer; non-ulcer dyspepsia
PMCID: PMC1727030  PMID: 9577338
12.  Helicobacter pylori Infection in an Urban African Population 
Journal of Clinical Microbiology  2001;39(4):1323-1327.
We have studied 221 adults drawn from an impoverished urban population with high human immunodeficiency virus (HIV) seroprevalence (35%) to determine the prevalence of gastroduodenal pathology and its relationship to serological markers of Helicobacter pylori virulence proteins and other potential environmental and immunological determinants of disease including HIV infection. Eighty-one percent were H. pylori seropositive, and 35% were HIV seropositive. Urban upbringing and low CD4 count were associated with a reduced likelihood of H. pylori seropositivity, as was current Ascaris infection, in keeping with recent evidence from an animal model. One hundred ninety-one adults underwent gastroduodenoscopy, and 14 had gastroduodenal pathology. Mucosal lesions were a major cause of abdominal pain in this population. While the majority of patients with gastroduodenal pathology (12 of 14) were seropositive for H. pylori, none were seropositive for HIV. Smoking was associated with increased risk of macroscopic pathology, and a history of Mycobacterium bovis BCG immunization was associated with reduced risk. Antibodies to H. pylori lipopolysaccharide were associated with pathology. HIV infection was associated with protection against mucosal lesions, suggesting that fully functional CD4 lymphocytes may be required for the genesis of gastroduodenal pathology.
PMCID: PMC87933  PMID: 11283050
13.  Helicobacter pylori Counteracts the Apoptotic Action of Its VacA Toxin by Injecting the CagA Protein into Gastric Epithelial Cells 
PLoS Pathogens  2009;5(10):e1000603.
Infection with Helicobacter pylori is responsible for gastritis and gastroduodenal ulcers but is also a high risk factor for the development of gastric adenocarcinoma and lymphoma. The most pathogenic H. pylori strains (i.e., the so-called type I strains) associate the CagA virulence protein with an active VacA cytotoxin but the rationale for this association is unknown. CagA, directly injected by the bacterium into colonized epithelium via a type IV secretion system, leads to cellular morphological, anti-apoptotic and proinflammatory effects responsible in the long-term (years or decades) for ulcer and cancer. VacA, via pinocytosis and intracellular trafficking, induces epithelial cell apoptosis and vacuolation. Using human gastric epithelial cells in culture transfected with cDNA encoding for either the wild-type 38 kDa C-terminal signaling domain of CagA or its non-tyrosine-phosphorylatable mutant form, we found that, depending on tyrosine-phosphorylation by host kinases, CagA inhibited VacA-induced apoptosis by two complementary mechanisms. Tyrosine-phosphorylated CagA prevented pinocytosed VacA to reach its target intracellular compartments. Unphosphorylated CagA triggered an anti-apoptotic activity blocking VacA-induced apoptosis at the mitochondrial level without affecting the intracellular trafficking of the toxin. Assaying the level of apoptosis of gastric epithelial cells infected with wild-type CagA+/VacA+ H. pylori or isogenic mutants lacking of either CagA or VacA, we confirmed the results obtained in cells transfected with the CagA C-ter constructions showing that CagA antagonizes VacA-induced apoptosis. VacA toxin plays a role during H. pylori stomach colonization. However, once bacteria have colonized the gastric niche, the apoptotic action of VacA might be detrimental for the survival of H. pylori adherent to the mucosa. CagA association with VacA is thus a novel, highly ingenious microbial strategy to locally protect its ecological niche against a bacterial virulence factor, with however detrimental consequences for the human host.
Author Summary
The gram-negative bacterium Helicobacter pylori is the main causative agent of peptic ulcer and gastric cancer in humans. Our work sheds light on a new molecular mechanism by which H. pylori would exert its highly efficient colonization strategy of the human host. In this paper, we show that the H. pylori CagA protein counteracts, by two distinct non-overlapping mechanisms, the apoptotic activity of the H. pylori VacA toxin on human gastric epithelial cells so as to allow a protection of the bacterium niche against VacA, giving a rationale for the association of these two virulence factors in the most pathogenic H. pylori strains. This is a new, highly ingenious mechanism by which a bacterium locally protects its ecological niche against the action of one of its own virulence factors. However, while exerting a beneficial role for survival and growth of the bacterium by counteracting VacA toxin, CagA injection in the gastric epithelial cells triggers proinflammatory and anti-apoptotic responses which are detrimental for the human host in the long-term and favor the development of ulcer and cancer.
PMCID: PMC2745580  PMID: 19798427
14.  Clinical features of gastroduodenal injury associated with long-term low-dose aspirin therapy 
Low-dose aspirin (LDA) is clinically used for the prevention of cardiovascular and cerebrovascular events with the advent of an aging society. On the other hand, a very low dose of aspirin (10 mg daily) decreases the gastric mucosal prostaglandin levels and causes significant gastric mucosal damage. The incidence of LDA-induced gastrointestinal mucosal injury and bleeding has increased. It has been noticed that the incidence of LDA-induced gastrointestinal hemorrhage has increased more than that of non-aspirin non-steroidal anti-inflammatory drug (NSAID)-induced lesions. The pathogenesis related to inhibition of cyclooxygenase (COX)-1 includes reduced mucosal flow, reduced mucus and bicarbonate secretion, and impaired platelet aggregation. The pathogenesis related to inhibition of COX-2 involves reduced angiogenesis and increased leukocyte adherence. The pathogenic mechanisms related to direct epithelial damage are acid back diffusion and impaired platelet aggregation. The factors associated with an increased risk of upper gastrointestinal (GI) complications in subjects taking LDA are aspirin dose, history of ulcer or upper GI bleeding, age > 70 years, concomitant use of non-aspirin NSAIDs including COX-2-selective NSAIDs, and Helicobacter pylori (H. pylori) infection. Moreover, no significant differences have been found between ulcer and non-ulcer groups in the frequency and severity of symptoms such as nausea, acid regurgitation, heartburn, and bloating. It has been shown that the ratios of ulcers located in the body, fundus and cardia are significantly higher in bleeding patients than the ratio of gastroduodenal ulcers in patients taking LDA. Proton pump inhibitors reduce the risk of developing gastric and duodenal ulcers. In contrast to NSAID-induced gastrointestinal ulcers, a well-tolerated histamine H2-receptor antagonist is reportedly effective in prevention of LDA-induced gastrointestinal ulcers. The eradication of H. pylori is equivalent to treatment with omeprazole in preventing recurrent bleeding. Continuous aspirin therapy for patients with gastrointestinal bleeding may increase the risk of recurrent bleeding but potentially reduces the mortality rates, as stopping aspirin therapy is associated with higher mortality rates. It is very important to prevent LDA-induced gastroduodenal ulcer complications including bleeding, and every effort should be exercised to prevent the bleeding complications.
PMCID: PMC3607744  PMID: 23555156
Gastroduodenal ulcer; Upper gastrointestinal bleeding; Low-dose aspirin; Non-steroidal anti-inflammatory drugs
15.  Helicobacter pylori-specific CD4+ T-cell clones from peripheral blood and gastric biopsies. 
Infection and Immunity  1995;63(3):1102-1106.
Colonization of human gastric mucosa with cytotoxic strains of the bacterium Helicobacter pylori is associated with peptic ulcer and with chronic gastritis. Since little is known about the T-cell response to H. pylori, we investigated the CD4+ T-cell response both in peripheral blood mononuclear cells (PBMCs) and at the site of infection. First, we compared the bulk PBMC proliferative response to the bacterium in individuals with and without symptoms of gastroduodenal disease. We found that the PBMCs from virtually all individuals proliferate in response to heat-inactivated bacteria. Second, we cloned H. pylori-specific CD4+ T lymphocytes from the PBMCs of three patients and from both the gastric mucosa and PBMCs of a fourth patient. We have found that CD4+ T-cell clones specific for H. pylori from peripheral blood samples and gastric mucosae of infected patients are major histocompatibility complex class II restricted and discriminate between several cytotoxic and noncytotoxic bacterial strains. Moreover, they are polyclonal in terms of T-cell receptor usage and major histocompatibility complex restriction. Our results demonstrate that the T-cell response to the whole bacterium in PBMCs does not correlate with antibody response, infection, or disease. However, H. pylori-specific CD4+ T cells are detectable, at the clonal level, in both the periphery and gastric mucosa of infected patients. Localization of these cells at the site of disease suggests they are effectors of the immune response to the bacteria.
PMCID: PMC173116  PMID: 7868233
16.  A decision support system to determine optimal ventilator settings 
Choosing the correct ventilator settings for the treatment of patients with respiratory tract disease is quite an important issue. Since the task of specifying the parameters of ventilation equipment is entirely carried out by a physician, physician’s knowledge and experience in the selection of these settings has a direct effect on the accuracy of his/her decisions. Nowadays, decision support systems have been used for these kinds of operations to eliminate errors. Our goal is to minimize errors in ventilation therapy and prevent deaths caused by incorrect configuration of ventilation devices. The proposed system is designed to assist less experienced physicians working in the facilities without having lung mechanics like cottage hospitals.
This article describes a decision support system proposing the ventilator settings required to be applied in the treatment according to the patients’ physiological information. The proposed model has been designed to minimize the possibility of making a mistake and to encourage more efficient use of time in support of the decision making process while the physicians make critical decisions about the patient. Artificial Neural Network (ANN) is implemented in order to calculate frequency, tidal volume, FiO2 outputs, and this classification model has been used for estimation of pressure support / volume support outputs. For the obtainment of the highest performance in both models, different configurations have been tried. Various tests have been realized for training methods, and a number of hidden layers mostly affect factors regarding the performance of ANNs.
The physiological information of 158 respiratory patients over the age of 60 and were treated in three different hospitals between the years 2010 and 2012 has been used in the training and testing of the system. The diagnosed disease, core body temperature, pulse, arterial systolic pressure, diastolic blood pressure, PEEP, PSO2, pH, pCO2, bicarbonate data as well as the frequency, tidal volume, FiO2, and pressure support / volume support values suitable for use in the ventilator device have been recommended to the physicians with an accuracy of 98,44%. Performed experiments show that sequential order weight/bias training was found to be the most ideal ANN learning algorithm for regression model and Bayesian regulation backpropagation was found to be the most ideal ANN learning algorithm for classification models.
This article aims at making independent of the choice of parameters from physicians in the ventilator treatment of respiratory tract patients with proposed decision support system. The rate of accuracy in prediction of systems increases with the use of data of more patients in training. Therefore, non-physician operators can use systems in determination of ventilator settings in case of emergencies.
PMCID: PMC3996182  PMID: 24410995
Ventilator settings; Decision support systems; Artificial neural networks; Bayesian model
17.  Comparative Genomics of Helicobacter pylori Strains of China Associated with Different Clinical Outcome 
PLoS ONE  2012;7(6):e38528.
In this study, a whole-genome CombiMatrix Custom oligonucleotide tiling microarray with 90000 probes covering six sequenced Helicobacter pylori (H. pylori) genomes was designed. This microarray was used to compare the genomic profiles of eight unsequenced strains isolated from patients with different gastroduodenal diseases in Heilongjiang province of China. Since significant genomic variation was found among these strains, an additional 76 H. pylori strains associated with different clinical outcomes were isolated from various provinces of China. These strains were tested by polymerase chain reaction to demonstrate this distinction. We identified several highly variable regions in strains associated with gastritis, gastric ulceration, and gastric cancer. These regions are associated with genes involved in the bacterial type I, type II, and type III R-M systems. They were also associated with the virB gene, which lies on the well-studied cag pathogenic island. While previous studies have reported on the diverse genetic characterization of this pathogenic island, in this study, we find that it is conserved in all strains tested by microarray. Moreover, a number of genes involved in the type IV secretion system, which is related to horizontal DNA transfer between H. pylori strains, were identified in the comparative analysis of the strain-specific genes. These findings may provide insight into new biomarkers for the prediction of gastric diseases.
PMCID: PMC3368837  PMID: 22701658
18.  Characteristics of Helicobacter pylori Infection in Jamaican Adults with Gastrointestinal Symptoms 
Journal of Clinical Microbiology  2001;39(1):212-216.
Helicobacter pylori infection is common in Jamaica. Describing its epidemiology in a population-based study depends largely on serology, but serologic assays have not been validated in this population. To address this issue, we examined the presence of H. pylori infection in 30 sequential adult patients with gastroduodenal symptoms by three biopsy-based methods (rapid urease test, histology, and culture) as well as by one research and two commercial enzyme-linked immunosorbent assays (ELISAs). A patient was considered H. pylori positive if the organism was detected by at least one biopsy-based method. Eighteen (60%) of the 30 patients were H. pylori positive by these criteria, whereas 21 (70%) were seropositive for H. pylori immunoglobulin G by our research ELISA. The presence of H. pylori infection in patients with gastric cancer and those with chronic gastritis was missed by biopsy-based methods but was detected by serologic assays. This observation indicates that serologic assays may be better suited for the detection of this infection in a population in which H. pylori-associated pathology is prevalent. The performance of our research ELISA in detecting biopsy-based H. pylori-positive cases was excellent, with a sensitivity and specificity of 100% and 75%, respectively. Molecular genotyping of the isolates revealed that the predominant H. pylori genotypes in this cohort of Jamaicans were cagA+ vacA slb-m1, and iceA2. The validated serologic assay enables us to interpret epidemiologic data from population-based studies in Jamaica by comparison to those from other populations.
PMCID: PMC87704  PMID: 11136773
19.  Chemokines and Antimicrobial Peptides Have a cag-Dependent Early Response to Helicobacter pylori Infection in Primary Human Gastric Epithelial Cells 
Infection and Immunity  2014;82(7):2881-2889.
Helicobacter pylori infection systematically causes chronic gastric inflammation that can persist asymptomatically or evolve toward more severe gastroduodenal pathologies, such as ulcer, mucosa-associated lymphoid tissue (MALT) lymphoma, and gastric cancer. The cag pathogenicity island (cag PAI) of H. pylori allows translocation of the virulence protein CagA and fragments of peptidoglycan into host cells, thereby inducing production of chemokines, cytokines, and antimicrobial peptides. In order to characterize the inflammatory response to H. pylori, a new experimental protocol for isolating and culturing primary human gastric epithelial cells was established using pieces of stomach from patients who had undergone sleeve gastrectomy. Isolated cells expressed markers indicating that they were mucin-secreting epithelial cells. Challenge of primary epithelial cells with H. pylori B128 underscored early dose-dependent induction of expression of mRNAs of the inflammatory mediators CXCL1 to -3, CXCL5, CXCL8, CCL20, BD2, and tumor necrosis factor alpha (TNF-α). In AGS cells, significant expression of only CXCL5 and CXCL8 was observed following infection, suggesting that these cells were less reactive than primary epithelial cells. Infection of both cellular models with H. pylori B128ΔcagM, a cag PAI mutant, resulted in weak inflammatory-mediator mRNA induction. At 24 h after infection of primary epithelial cells with H. pylori, inflammatory-mediator production was largely due to cag PAI substrate-independent virulence factors. Thus, H. pylori cag PAI substrate appears to be involved in eliciting an epithelial response during the early phases of infection. Afterwards, other virulence factors of the bacterium take over in development of the inflammatory response. Using a relevant cellular model, this study provides new information on the modulation of inflammation during H. pylori infection.
PMCID: PMC4097638  PMID: 24778119
20.  Helicobacter pylori associated gastric diseases and lymphoid tissue hyperplasia in gastric antral mucosa 
Journal of Clinical Pathology  2002;55(2):133-137.
Aim: To investigate the relation between Helicobacter pylori associated gastroduodenal diseases and lymphoid tissue hyperplasia in the antral mucosa and to pursue its evolution after eradication of H pylori.
Methods: Gastric antral biopsy specimens were obtained from 438 patients with H pylori positive gastroduodenal diseases (185 chronic gastritis, 69 gastric ulcer, and 184 duodenal ulcer) and 50 H pylori negative healthy controls. Lymphoid follicles and aggregates were counted and other pathological features were scored according to the updated Sydney system for classification of chronic gastritis. After a course of anti-H pylori treatment, biopsy specimens were obtained at four to six weeks, 12 months, and 24 months in the chronic gastritis patient group.
Results: The total prevalence of lymphoid follicles and aggregates in the biopsies was 79.9% (350 of 438; 95% confidence intervals (CI), 0.76 to 0.84). The prevalence and density of lymphoid follicles and aggregates were significantly different in the various gastroduodenal diseases. The highest prevalence (89.9%; 95% CI, 0.83 to 0.97) and density (0.82) of lymphoid follicles and aggregates occurred in patients with gastric ulcers. The lowest prevalence of lymphoid follicles and aggregates was found in patients with chronic gastritis (74.6%; 95% CI, 0.68 to 0.81), and the lowest density of lymphoid follicles and aggregates (0.56) was seen in patients with duodenal ulcers. The prevalence and density of lymphoid follicles and aggregates correlated strongly with the activity and severity of gastric antral mucosal inflammation. The eradication of H pylori resulted in a decrease in the prevalence and density of lymphoid follicles and aggregates.
Conclusion: The prevalence and density of lymphoid follicles and aggregates in gastric antral mucosal biopsies correlated closely with H pylori infection.
PMCID: PMC1769586  PMID: 11865009
Helicobacter pylori associated gastroduodenal diseases; lymphoid follicles; lymphoid aggregates; eradication
21.  Houseflies Are an Unlikely Reservoir or Vector for Helicobacter pylori 
Journal of Clinical Microbiology  1998;36(9):2786-2788.
The route of transmission of Helicobacter pylori from individual to individual remains undefined. It has recently been reported that the domestic housefly, Musca domestica, when fed pure cultures of H. pylori, was able to harbor the organism in its midgut for up to 30 h (P. Grubel, S. Hoffman, F. K. Chong, N. A. Barstein, C. Mepani, and D. R. Cave, J. Clin. Microbiol. 35:1300–1303, 1997). Our investigation examined whether houseflies could acquire H. pylori from fresh human feces. Domestic houseflies (40 flies/group) were exposed for 24 h to feces from an H. pylori-positive volunteer, feces from an H. pylori-negative volunteer, or feces from an H. pylori-negative volunteer to which a known amount of viable H. pylori had been added. At various intervals, flies were sacrificed and the midguts were excised, homogenized, and plated in duplicate onto selective horse blood agar plates. All plates were incubated under microaerobic conditions at 37°C for 14 days. Emergent colonies presumptive of H. pylori were picked and tested biochemically to confirm the identity as H. pylori. H. pylori was not recovered from houseflies fed human feces either naturally infected or artificially infected with H. pylori. These results suggest that the domestic housefly is not a vector for transmission or a reservoir for H. pylori infection.
PMCID: PMC105211  PMID: 9705441
22.  Immunoglobulin G Antibody against Helicobacter pylori: Clinical Implications of Levels Found in Serum 
The clinical significance of high levels of antibody against Helicobacter pylori is still unclear. We sought to evaluate whether the serum antibody levels could predict the presence of macroscopic gastroduodenal disease, to identify factors that correlate with antibody levels in a multivariate context, and to determine the predictive value of antibody levels for diagnosing H. pylori infection. The grades of gastritis and density of H. pylori colonization were scored separately using the updated Sydney system for antral and body mucosa. An enzyme-linked immunosorbent assay (ELISA) for the quantitative detection in serum of IgG antibodies to H. pylori was performed. Of the 170 dyspeptic patients, 105 (62%) had H. pylori infection. There was no difference in antibody levels among endoscopic findings of normal mucosa, chronic gastritis, and duodenal ulcer. On multivariate linear regression analysis, the status of H. pylori infection, mononuclear cell infiltration of body mucosa, and age correlated with antibody levels. The negative predictive value for antibody levels of <30 U/ml is 94%, and the positive predictive value of antibody levels of >70 U/ml is 98%. We conclude that serum antibody levels do not predict the severity of gastroduodenal diseases or the density of H. pylori colonization in H. pylori-infected dyspeptic patients. Higher levels are associated with the presence of H. pylori infection, the chronic gastritis score of the corpus, and older age. Setting a gray zone is necessary for ELISA, since the accuracy in this zone does not allow a precise determination of H. pylori status.
PMCID: PMC120058  PMID: 12204957
23.  Apert's Syndrome 
Apert's syndrome (acrocephalosyndactyly) is a rare congenital disorder characterized by craniosynostosis, midfacial malforma­tion and symmetrical syndactyly of hands and feet. Craniofacial deformities include cone-shaped calvarium, fat forehead, prop-tosis, hypertelorism and short nose with a bulbous tip. Intraoral findings include high arched palate with pseudocleft, maxillary transverse and sagittal hypoplasia with concomitant dental crowding, skeletal and dental anterior open bite and several retained primary teeth. We report one such case of 14-year-old boy having all the classical features of Apert's syndrome with particular emphasis on brief review of genetic features.
How to cite this article: Kumar GR, Jyothsna M, Ahmed SB, Lakshmi KRS. Apert's Syndrome. Int J Clin Pediatr Dent 2014;7(1):69-72.
PMCID: PMC4144061  PMID: 25206244
Acrocephalosyndactyly; Craniosynostosis; Midface hypoplasia; Pseudocleft palate
24.  Diversity of Helicobacter pylori genotypes in Iranian patients with different gastroduodenal disorders 
AIM: To investigate the diversity of Helicobacter pylori (H. pylori) genotypes and correlations with disease outcomes in an Iranian population with different gastroduodenal disorders.
METHODS: Isolates of H. pylori from patients with different gastroduodenal disorders were analyzed after culture and identification by phenotypic and genotypic methods. Genomic DNA was extracted with the QIAamp DNA mini kit (Qiagen, Germany). After DNA extraction, genotyping was done for cagA, vacA (s and m regions), iceA (iceA1, iceA2) and babA with specific primers for each allele using polymerase chain reaction (PCR). All patients’ pathologic and clinical data and their relation with known genotypes were analyzed by using SPSS version 19.0 software. χ2 test and Fisher’s exact test were used to assess relationships between categorical variables. The level of statistical significance was set at P < 0.05.
RESULTS: A total of 71 isolates from 177 patients with different gastroduodenal disorders were obtained. Based on analysis of the cagA gene (positive or negative), vacA s-region (s1 or s2), vacA m-region (m1 or m2), iceA allelic type (iceA1 and iceA2) and babA gene (positive or negative), twenty different genotypic combinations were recognized. The prevalence of cagA, vacA s1, vacA s2, vacA m1, vacA m2, iceA1, iceA2, iceA1+iceA2 and babA were 62%, 78.9%, 19.7%, 21.1%, 78.9%, 15.5%, 22.5%, 40.8% and 95.8%, respectively. Interestingly, evaluation of PCR results for cagA in 6 patients showed simultaneous existence of cagA variants according to their size diversities that proposed mixed infection in these patients. The most prevalent genotype in cagA-positive isolates was cagA+/vacAs1m2/iceA1+A2/babA+ and in cagA-negative isolates was cagA-/vacAs1m2/iceA-/babA+. There were no relationships between the studied genes and histopathological findings (H. pylori density, neutrophil activity, lymphoid aggregation in lamina propria and glandular atrophy). The strains which carry cagA, vacAs1/m1, iceA2 and babA genes showed significant associations with severe active chronic gastritis (P = 0.011, 0.025, 0.020 and 0.031, respectively). The vacAs1 genotype had significant correlation with the presence of the cagA gene (P = 0.013). Also, babA genotype showed associations with cagA (P = 0.024). In the combined genotypes, only cagA+/vacAs1m1/iceA2/babA+ genotype showed correlation with severe active chronic gastritis (P = 0.025).
CONCLUSION: This genotyping panel can be a useful tool for detection of virulent H. pylori isolates and can provide valuable guidance for prediction of the clinical outcomes.
PMCID: PMC3769906  PMID: 24039362
Helicobacter pylori; cagA; vacA; iceA; babA
25.  New semisynthetic pneumocandins with improved efficacies against Pneumocystis carinii in the rat. 
A new series of semisynthetic, water-soluble pneumocandin analogs has been found to be extremely potent against Pneumocystis carinii in an immunocompromised-rat model. These compounds are 5 to 10 times more potent than the parent natural product, pneumocandin B0 (L-688,786) (R. E. Schwartz et al., J. Antibiot. 45:1853-1866, 1992), and > 100 times more potent than cilofungin. One compound in particular, L-733,560, had a 90% effective dose against P. carinii cysts of 0.01 mg/kg of body weight when delivered parenterally (subcutaneously, twice daily for 4 days). This compound was also effective when given orally for the treatment and prevention of P. carinii pneumonia. For treating acute P. carinii pneumonia, oral doses of 2.2 mg/kg twice daily for 4 days were required to eliminate 90% of the cysts. A once-daily oral prophylactic dose of 2.2 mg/kg prevented cyst development, and a dose of 6.2 mg/kg prevented any development of P. carinii organisms (cysts and trophozoites), as determined through the use of a P. carinii-specific DNA probe (P. A. Liberator et al., J. Clin. Microbiol. 30:2968-2974, 1992). These results demonstrate that the antipneumocystis activities of the pneumocandins can be significantly improved through synthetic modification. Several of these compounds are also extremely effective against candidiasis (K. Bartizal et al., Antimicrob. Agents Chemother. 39:1070-1076, 1995) and aspergillosis (G. K. Abruzzo et al., Antimicrob. Agents Chemother. 39:860-894, 1995) in murine models, making them attractive as broad-spectrum antifungal agents.
PMCID: PMC162734  PMID: 7574523

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