Detection of infectious agents by polymerase chain reaction in human aortic wall

The Detection of Chlamydia pneumoniae, Helicobacter pylori and Cytomegalovirus in Non-Atherosclerotic Arteries of Patients with Coronary Artery Disease

Atherosclerotic coronary artery disease (ACAD) is a major cause of global morbidity and mortality, characterized as an inflammatory process due to damage to blood vessel walls by risk factors like aging, hyperlipidemia, hypertension, smoking, and diabetes. Infectious agents, including Chlamydia pneumoniae (Cpn), Cytomegalovirus (CMV), and Helicobacter pylori (HP), have been implicated in ACAD's pathophysiology. A study with 56 subjects undergoing coronary artery bypass grafting (CABG) aimed to detect Cpn, CMV, and HP DNA in unaffected artery segments and explore associations with disease progression and inflammation markers. The study found infectious agents' DNA in 21.4% of samples, HP in eight samples, and CMV and Cpn in four samples each. Significant correlations were observed between HP and overweight or obese subjects, as well as between the presence of infectious agents and inflammation marker values. An association between HP and renal function was also noted. The findings reaffirm previous discoveries of infectious agents in non-clinically affected arteries used as CABG grafts. Correlations identified between the presence of HP, CMV, and Cpn DNA in grafts and several biomarkers of inflammation and obesity emphasize the potential role of these infectious agents in ACAD pathogenesis.

Comparison of Helicobacter pylori in hospitalized COVID-19 patients with and without gastrointestinal symptoms

Background and Aim

Helicobacter pylori plays an important role in causing digestive diseases. The purpose of this study is to investigate Helicobacter pylori in COVID-19 patients with and without gastrointestinal symptoms.

Methods

In this case-control study, all patients with COVID-19 admitted to Imam Khomeini Hospital in Jiroft city in 2021 were convenience sampled and divided into two homogeneous groups. Ninety-five patients with COVID-19, who presented with gastrointestinal symptoms, were included in the case group, while 95 patients with COVID-19 without gastrointestinal symptoms were included in the control group. Noninvasive diagnostic methods, including serology and stool antigen tests, were used to identify Helicobacter pylori in the studied patients.

Results

Fifty-three people (55.8%) from the case group had Helicobacter pylori, and 48 (50.5%) from the control group had Helicobacter pylori. Among the 53 people from the case group, 27 (50.9%) were men and 26 (49.1%) were women. Nineteen people (35.8%) were taking pantoprazole, 10 people (18.8%) were taking nonsteroidal anti-inflammatory drugs, 20 people (37.7%) were taking narcotics, and 7 people (13.2%) had peptic ulcer. Seven people (13.2%) had an H2 blocker, and 21 people had an underlying disease. A significant relationship between infection with Helicobacter pylori and the use of pantoprazole, nonsteroidal anti-inflammatory drugs, narcotics, peptic ulcer, underlying disease, and H2 blocker in COVID-19 patients with gastrointestinal symptoms and without gastrointestinal symptoms was present (P-value < 0.05).

Conclusion

The prevalence of Helicobacter pylori infection in patients with COVID-19, who have gastrointestinal symptoms, is high and should be considered as a treatment criterion for people infected with COVID-19.

Causality of anti-Helicobacter pylori IgG levels on myocardial infarction and potential pathogenesis: a Mendelian randomization study

Background

Previous observational studies have shown that a potential relationship between anti-Helicobacter pylori (H. pylori) IgG levels and Myocardial Infarction (MI). Nevertheless, the evidence for the causal inferences remains disputable. To further clarify the relationship between anti-H. pylori IgG levels and MI and explore its pathogenesis, we conducted a Mendelian randomization (MR) analysis.

Methods

In this study, we used two-sample Mendelian Randomization (MR) to assess the causality of anti-H. pylori IgG levels on MI and potential pathogenesis, 12 single nucleotide polymorphisms (SNPs) related to anti-H. pylori IgG levels were obtained from the European Bioinformatics Institute (EBI). Summary data from a large-scale GWAS meta-analysis of MI was utilized as the outcome dataset. Summary data of mediators was obtained from the FinnGen database, the UK Biobank, the EBI database, MRC-IEU database, the International Consortium of Blood Pressure, the Consortium of Within family GWAS. Inverse variance weighted (IVW) analysis under the fixed effect model was identified as our main method. To ensure the reliability of the findings, many sensitivity analyses were performed.

Results

Our study revealed that increases of anti-H. pylori IgG levels were significantly related to an increased risk of MI (OR, 1.104; 95% CI,1.042-1.169; p = 7.084 × 10-4) and decreases in HDL cholesterol levels (β, -0.016; 95% CI, -0.026 to -0.006; p = 2.02 × 10-3). In addition, there was no heterogeneity or pleiotropy in our findings.

Conclusion

This two-sample MR analysis revealed the causality of anti-H. pylori IgG levels on MI, which might be explained by lower HDL cholesterol levels. Further research is needed to clarify the results.

Prevalence of Microorganisms in Atherosclerotic Plaques of Coronary Arteries: A Systematic Review and Meta-Analysis

Background

In this systematic review and meta-analysis, the existence of pathogens in atherosclerotic plaques of coronary arteries was investigated in coronary arteries diseases (CAD) patients.

Methods

This study was designed and implemented up to 31 August 2020. The findings present according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) checklist. Two independent reviewers (I.RJ and S.H) performed a comprehensive search on four different English databases including PubMed, ISI, Scopus, and Embase. In order to assess the quality of the articles, a checklist prepared by The Joanna Briggs Institute (JBI) was used.

Results

Finally, 44 studies were selected. The prevalence of different microorganisms in coronary arteries were as follows: Aggregatibacter actinomycetemcomitans (46.2%), Campylobacter rectus (43.0%), Chlamydia pneumonia (42.8%), Cytomegalovirus (29.1%), Helicobacter pylori (18.9%), Herpes simplex virus type 1 (5.9%), Porphyromonas gingivalis (42.6%), Prevotella intermedia (47.6%), Tannerella forsythia (43.7%), and Treponema denticola (32.9%).

Conclusion

Based on the result of this meta-analysis, Prevotella intermedia and Aggregatibacter actinomycetemcomitans are the most common microorganisms in atherosclerotic plaques of coronary arteries and may have an important role in the development of atherosclerosis.

Reliable and Sensitive Nested PCR for the Detection of Chlamydia in Sputum

Chlamydia are Gram-negative, intracellular pathogens colonizing epithelial mucosa. They cause primarily atypical pneumonia and have recently been associated with chronic diseases. Diagnostics relies almost exclusively on serological methods; PCR tests are used rarely because in patients with positive ELISA, it is nearly impossible to identify chlamydial DNA. This paradox is associated with DNA degradation in sputum samples, low abundance, and low sensitivity of PCR systems. In a newly designed and validated “nested” PCR (NPCR) assay, it was possible to amplify DNA of Chlamydia known to infect humans in 31% samples. The reliability of the assay was confirmed by DNA sequencing, and all PCR products belonged exclusively to the Chlamydiales, mainly recognized as Chlamydia pneumoniae. Three samples were related to Ca. Rhabdochlamydia porcellionis and Ca. Renichlamydia lutjani, which infect arthropods. In one case, samples were taken from sick individual, indicating the potential as a human pathogen.

T cell responses to an HLA-A2-restricted adipophilin peptide correlate with BMI in patients with atherosclerosis

Introduction

Atherosclerosis is an inflammatory disease causing a vast array of cardiovascular diseases. Adipophilin has been reported to be highly expressed in atherosclerotic lesions. This study investigated the possible existence of auto-reactive T cells against an HLA-A02-restricted adipophilin-derived peptide as well as peptides from Epstein-barr virus (EBV), Cytomegalovirus (CMV) and influenza (Flu) virus in patients with atherosclerosis.

Methods

HLA-A02 expression on peripheral blood mononuclear cells (PBMCs) was examined by flow cytometry. PBMCs from HLA-A02 individuals were stimulated with adipophilin, CMV, EBV, and Flu peptides at a concentration of 10 µM. Interferon (IFN)-γ production was evaluated in the culture supernatant using a commercial ELISA test.

Results

The levels of IFN-γ production against an HLA-A02-restricted adipophilin peptide and peptides from CMV, EBV, and Flu revealed no statistically significant differences between patients and healthy controls. However, we found a positive correlation between IFN-γ production against adipophilin and Body mass index (BMI) of patients (R = 0.8, P = 0.003), whereas no significant correlation was found in healthy controls (R = -0.267, P = 0.378). No correlation between BMI and IFN-γ production against CMV, EBV, or Flu peptides was found.

Discussion

Atherosclerotic patients with higher BMIs might have greater numbers of T cells against adipophilin that is highly expressed in atherosclerotic plaques. Therefore, autoimmune reactions may have a greater role in the development of atherosclerosis in individuals with higher BMI.

Bacterial infections are associated with cardiovascular disease in Iran: a meta-analysis

INTRODUCTION

The present study aimed to assess the prevalence and association of various bacterial infections with cardiovascular disease (CVD) in Iran.

MATERIAL AND METHODS

An electronic search was performed using related keywords in the national and international databases up to June 30, 2017. Out of the 1807 articles found on the associations between bacterial infections and CVD, 20 relevant studies were selected for the meta-analysis.

RESULTS

The prevalence of bacterial infections was higher in case groups compared with the control groups. Odds ratios for assessing the association between Chlamydia pneumonia infection and CVD based on PCR, IgG and IgA tests were 7.420 (95% CI: 3.088-17.827), 3.710 (95% CI: 1.361-10.115) and 2.492 (95% CI: 1.305-4.756), respectively. Moreover, the calculated odds ratio for Mycoplasma pneumonia infection was 1.815 (95% CI: 0.973-3.386). For Helicobacter pylori infection, odds ratios based on IgG and IgA tests were 3.160 (95% CI: 1.957-5.102) and 0.643 (95% CI: 0.414-0.999), respectively.

CONCLUSIONS

The present meta-analysis suggested that there was a significant association between H. pylori, C. pneumonia and M. pneumonia infections and CVD in Iran. These findings confirm the potential role of bacterial infections as predisposing factors for CVD.

Lipoproteins in Atherosclerosis Process

BACKGROUND

Dyslipidaemias is a recognized risk factor for atherosclerosis, however, new evidence brought to light by trials investigating therapies to enhance HDLcholesterol have suggested an increased atherosclerotic risk when HDL-C is high.

RESULTS

Several studies highlight the central role in atherosclerotic disease of dysfunctional lipoproteins; oxidised LDL-cholesterol is an important feature, according to "oxidation hypothesis", of atherosclerotic lesion, however, there is today a growing interest for dysfunctional HDL-cholesterol. The target of our paper is to review the functions of modified and dysfunctional lipoproteins in atherogenesis.

CONCLUSION

Taking into account the central role recognized to dysfunctional lipoproteins, measurements of functional features of lipoproteins, instead of conventional routine serum evaluation of lipoproteins, could offer a valid contribution in experimental studies as in clinical practice to stratify atherosclerotic risk.

Potential Anti-Inflammatory Treatment of Ischemic Heart Disease

Introduction

Ischemic heart disease (IHD) is clinical manifestation of chronic inflammatory progressive pathological process of atherosclerosis in coronary arteries. IHD is the leading cause of morbidity and mortality in the world. The question is whether it is possible to improve and direct the therapeutic treatment of IHD patients in the treatment of the inflammatory process in the atherosclerotic leasions.

Material and Methods

A prospective, comparative, analytica,clinically applicable, open-type study was performed. The study was conducted on 80 subjects with controlled biohumoral markers: troponin, CK, CK MB, BNP; markers of atherogenesis: LDL and homocystein; inflammatory markers: CRP, amyloid, cytokines IL-2, IL-6,TNF-alpha. The experimental group of 38 respondents had in addition to the conventional IHD treatment with: ampicillin (which included organosulfur compounds), cyancobalamin, vitamin B complex (B1, B2 and B6) and folacin. A control group of 42 respondents did not have this additional treatment.

Results

Major adverse cardic events (MACE) such as postinfarctic angina pectoris and repeated infarction, need for surgical interventions of myocardial revascularization, signs of cardiac insufficiency and death were observed during the one-year period. There was no correlation between the IL-2, IL-6 and TNF-alpha, as well as CK, CKMB and troponin and MACE in one-year follow-up. There was a strong positive correlation between MACE and CRP (p = 0,0002) and amyloid (p = 0,0005) as inflamatory markers; a strong positive correlation between MACE and homocysteine as an atherogenic marker (p = 0,0002, and amoderate positive correlation between MACE and BNP (p = 0.0403) as ischemic marker and marker of cardiac insufficiency. The echocardiographically monitored systolic function showed a moderate difference in the groups with average higher values in the experimantal group (p = 0.0282).

Conclusion

The applied treatment exhibited a moderate positive effect on the systolic function of LV and significantly reduced the MACE in the work compared to the control group (p <0.0001), and demonstrated a potential anti-inflammatory effect.

New Insights on the Pathogenesis of Takayasu Arteritis: Revisiting the Microbial Theory

Takayasu arteritis (TAK) is a chronic vasculitis that mainly affects the aorta, its major branches, and the pulmonary arteries. Since the description of the first case by Mikito Takayasu in 1908, several aspects of this rare disease, including the epidemiology, diagnosis, and the appropriate clinical assessment, have been substantially defined. Nevertheless, while it is well-known that TAK is associated with a profound inflammatory process, possibly rooted to an autoimmune disorder, its precise etiology has remained largely unknown. Efforts to identify the antigen(s) that trigger autoimmunity in this disease have been unsuccessful, however, it is likely that viruses or bacteria, by a molecular mimicry mechanism, initiate or propagate the auto-immune process in this disease. In this article, we summarize recent advances in the understanding of TAK, with emphasis on new insights related to the pathogenesis of this entity that may contribute to the design of novel therapeutic approaches.

Association of Helicobacter Pylori with Presence of Myocardial Infarction in Iran: A Systematic Review and Meta-Analysis

Background

Over the past decade, cardiovascular diseases have been recognized as the leading cause of mortality worldwide. Myocardial infarction (MI) is one of the most prevalent types of cardiovascular diseases that is caused by the closure of coronary arteries and ischemic heart muscle. Numerous studies have analyzed the role of H. pylori as a possible risk factor for coronary artery diseases, in most of which the role of infection in coronary artery disease is not statistically significant.

Methods

These contradictory findings made us conduct a systematic review to analyze all relevant studies in Iran through a meta-analysis and report a comprehensive and integrated result. All published studies from September 2000 until September 2016 were considered. Using reliable Latin databases like PubMed, Google Scholar, Google search, Scopus, Science Direct and Persian databases like SID, Irandoc, Iran Mede and Magiran. After quality control, these studies were entered into a meta-analysis by using the random effects model. After evaluating the studies, 11 papers were finally selected and assessed.

Results

A total of 2517 participants had been evaluated in these studies, including 1253 cases and 1264 controls. Based on the results of meta-analysis and using random effects model, an overall estimate of OR Helicobacter Pylori with Presence of Myocardial Infarction in Iran was OR=2.53 (CI=1.37-4.67).

Conclusions

The results of this review study show that H. pylori are associated with the incidence of MI so that the odds ratio of MI in the patients with helicobacter pylori is twice greater than that of the people without H. pylori. Future studies are recommended to evaluate the mechanisms associated with relation of H. pylori with MI as well as its association with time.

Infections and the risk of incident giant cell arteritis: a population-based, case-control study

OBJECTIVES

Alterations in the immune system and infections are suspected to increase susceptibility to giant cell arteritis (GCA). Recently herpes zoster has been directly implicated in the pathogenesis of GCA. We examined the association between prior infections, in particular herpes zoster, and incident GCA in a population-based cohort.

METHODS

A nested case-control study was performed using an electronic database from the UK. Cases with newly diagnosed GCA were identified using a validated algorithm and compared with age-matched, sex-matched and practice-matched controls. Conditional logistic regression was used to examine the relationship between any infection or herpes zoster infection on the development of GCA after adjusting for potential confounders; results were expressed as incidence rate ratios (IRRs).

RESULTS

There were 4559 cases of GCA and 22 795 controls. Any prior infection and herpes zoster were associated with incident GCA (IRR 1.26 (95% CI 1.16 to 1.36), p<0.01; and 1.17 (95% CI 1.04 to 1.32), p<0.01, respectively). A greater number of infections was associated with a higher risk of developing GCA (IRR for 1, 2-4 and ≥5 infections was 1.28, 1.60 and 2.18, respectively).

CONCLUSIONS

Antecedent infections and, to a lesser extent, herpes zoster infections are modestly associated with incident GCA. These data provide population-level support for the hypothesis that long-standing alterations of the immune system are associated with susceptibility to GCA and suggest that herpes zoster is unlikely to play a major causal role in the pathogenesis of GCA.

Human cytomegalovirus infection and vascular disease risk: A meta-analysis

BACKGROUND

Human cytomegalovirus (HCMV) infection has been associated with the acceleration of vascular disease. Numbers studies were conducted to analyze the association between HCMV infection and risk of vascular disease, but no clear consensus had been reached. The aim of this study was to confirm this relationship precisely by doing a systematic review and meta-analysis.

METHODS

We identified relevant studies through a search of PubMed and Embase. Studies were eligible for inclusion if they fulfilled all of the following selection criteria: (1) evaluating the association between HCMV infection and vascular disease; (2) case-control studies or nested case-control studies; (3) and supply the numbers (or percentage) of positivity for HCMV infection in cases and controls, respectively. Data were extracted and analyzed independently by two investigators. Ultimately, We included data from 68 studies, which altogether enrolled 12027 cases and 15386 controls from 24 countries.

RESULTS

HCMV IgG was detected 7376 in 10611 cases, HCMV IgM was detected 153 in 1486 cases and HCMV DNA was detected 654 in 2139 cases. Overall, people exposed to HCMV infection had higher risk than those not exposed for vascular disease (OR 1.70 [95% CI 1.43-2.03] IgG-based HCMV tests, 2.88 [95% CI 1.87-4.43] IgM-based HCMV tests and 2.56 [95% CI 1.46-4.49 PCR-based HCMV tests]). HCMV infection was clearly identified as a risk factor for vascular disease in Asian group, Caucasian group and other group, especially Asian group(OR 1.86 [95% CI 1.33-2.60] IgG-based HCMV tests, 3.57 [95% CI 1.94-6.60] IgM-based HCMV tests and 4.09 [95% CI 3.10-5.40 PCR-based HCMV tests]).

CONCLUSION

This meta-analysis suggested that HCMV infection is associated with an increased risk for vascular disease.

Multiple Infectious Agents and the Origins of Atherosclerotic Coronary Artery Disease

Although deaths due to atherosclerotic coronary artery disease (ACAD) have fallen dramatically during the past 50 years, ACAD remains as the leading cause of death in all continents, except Africa, where deaths due to infections are still dominant. Although food and nutrition have a proven role in atherosclerosis, the underlying causes of ACAD remain unknown. This is despite a century of intensive research dominated by investigations into the saturated fat hypothesis. In this review, it is hypothesized that the rise and fall in ACAD during the past 100 years is primarily due to the parallel rise and fall in the prevalence of coronary atheroma, the underlying disease. It is further hypothesized that infectious pathogens initiate atherosclerosis mainly during infancy and childhood. It is speculated that widespread use of antibiotics and vaccines against bacterial and viral infections may be the reason for the dramatic fall in coronary atheroma and ACAD during the past 50 years. The relevant evidence and a working hypothesis are included in this review.

Evidence for a vascular microbiome and its role in vessel health and disease

PURPOSE OF REVIEW

We have summarized available evidence for and against the presence of a vascular microbiome. Studies that have attempted to detect bacteria and viruses in blood vessels in both health and disease are critiqued in an attempt to explain contrary results that may be due to variations in methodology.

RECENT FINDINGS

Many studies have demonstrated the presence of both bacteria and viruses within diseased blood vessels. Evidence is most compelling in atherosclerosis; however, recent reports have raised questions about the potential role of microbes in nonatherosclerotic aortic aneurysms and vasculitis. Preliminary evidence also suggests that apparently normal vessels may harbor microbes. With the exception of certain viral infections (e.g. hepatitis C virus, HIV, Epstein-Barr virus, and cytomegalovirus) and infectious endocarditis, systemic vasculitides have not been convincingly associated with infectious agents. However, emerging data suggest that different communities of microbes may be present in noninflammatory and inflammatory large-vessel diseases. Whether variations in vascular microbial communities are the cause or a secondary result (epiphenomena) of vessel injury remains to be determined.

SUMMARY

Blood vessels may not be sterile. Future studies of microbes in vessel health and disease may provide important insights into disease pathogenesis and suggest new therapies for diseases now considered to be idiopathic and refractory.

Association of Chlamydia pneumoniae Infection With Atherosclerotic Plaque Formation

Atherosclerosis is a complex multifactorial disorder. Studies show that infectious microbial agents may play an important role in the development of atherosclerosis; however, these findings are conflicting. This study investigated the presence of Chlamydia pneumoniae DNA in atherosclerotic plaques of patients suffering from coronary artery disease. In a cross-sectional study, 85 patients (43 females and 42 males with mean age of 61±9.5, range 42-82 years) referred for coronary artery bypass grafting (CABG) and thoracic biopsy as the control groups were enrolled for this study. Standard questionnaires, including demographic and clinical evaluation were administered. Obtained specimens were processed and then nested polymerase chain reaction with primers for Pst1 fragment was carried out to detect Chlamydia pneumoniae DNA. Statistical analysis was done using the SPSS software. Of note, in 25 out of the 85 patients (29.4%), C. pneumoniae was detected within atherosclerotic plaques, whereas, 5 out of the 85 thoracic biopsy (5.9%) were positive for the presence of the mentioned bacteria in internal thoracic artery. There was a statistically significant association between atherosclerotic plaque (study group) and thoracic biopsy (control group) in terms of C. pneumoniae positivity (P=0.0001). The findings of this study support the hypothesis that C. pneumoniae is associated with atherosclerosis.

Infection and Atherosclerosis Development

Atherosclerosis is a chronic disease hallmarked by chronic inflammation, endothelial dysfunction and lipid accumulation in the vasculature. Although lipid modification and deposition are thought to be a major source of the continuous inflammatory stimulus, a large body of evidence suggests that infectious agents may contribute to atherosclerotic processes. This could occur by either direct effects through infection of vascular cells and/or through indirect effects by induction of cytokine and acute phase reactant proteins by infection at other sites. Multiple bacterial and viral pathogens have been associated with atherosclerosis by seroepidemiological studies, identification of the infectious agent in human atherosclerotic tissue, and experimental studies demonstrating an acceleration of atherosclerosis following infection in animal models of atherosclerosis. This review will focus on those infectious agents for which biological plausibility has been demonstrated in animal models and on the challenges of proving a role of infection in human atherosclerotic disease.

Helicobacter pylori Infection Increase the Risk of Myocardial Infarction: A Meta-Analysis of 26 Studies Involving more than 20,000 Participants

BACKGROUND

Myocardial infarction is a fatal cardiovascular disease and one of the most common death causes all around the world. The aim of the meta-analysis was to quantify the risk of myocardial infarction associated with Helicobacter pylori infection.

METHODS

A literature search was performed to identify studies published before 14 July, 2014, for relevant risk estimates. Fixed and random effect meta-analytical techniques were conducted for myocardial infarction.

RESULTS

Twenty-six case-control studies involving 5829 myocardial infarction patients and more than 16,000 controls were included. Helicobacter pylori infection was associated with an increased risk of myocardial infarction (OR: 2.10, 95%CI: 1.75-2.53, p = .06). We also discovered a significant association between the bacteria and risk of myocardial infarction in young people (OR: 1.93, 95% CI: 1.41-2.66, p = .07), in elder people (OR: 2.02, 95% CI: 1.60-2.54, p = .29), in Caucasians (OR: 2.29, 95% CI: 1.99-2.63, p = .12), and in Asians (OR: 1.75, 95% CI: 1.12-2.73, p = .08).

CONCLUSION

Our meta-analyses suggested a possible indication of relationship between Helicobacter pylori infection and the risk of myocardial infarction. The pathogenicity might not be affected by age and race. More researches should be conducted to explore the mechanisms involved.

A prospective study of the clinical characteristics of patients with herpes simplex and varicella zoster keratitis, presenting to a New Zealand emergency eye clinic

PURPOSE

To identify the demographic and clinical associations of patients presenting with herpetic keratitis in New Zealand compared with presentations of presumed microbial keratitis.

METHODS

A prospective, 6-month, observational case series of presumed microbial keratitis (including marginal keratitis), specifically identifying all cases of herpes simplex and varicella zoster keratitis attending an emergency eye clinic was conducted. Main outcome measures included demographics, presenting signs and symptoms, and medical, ocular, and drug history.

RESULTS

A total of 140 cases of herpetic keratitis were identified, which comprised 125 cases of herpes simplex virus (89%) and 15 cases of varicella zoster virus (11%). Herpes simplex keratitis was associated with a history of keratitis (n = 58, phi = 0.24, P < 0.0001), Maori ethnicity (n = 27, phi = 0.26, P < 0.0001), respiratory disease (n = 18, phi = 0.14, P = 0.009), corticosteroid use (n = 23, phi = 0.22, P < 0.0001), and cardiovascular disease (CVD) (n = 10, phi = 0.11, P = 0.03). Inverse association was observed between herpes simplex keratitis and ocular surface disease (n = 8, phi = -0.16, P < 0.002) and Asian ethnicity (n = 4, phi = -0.11, P = 0.04). Varicella zoster keratitis was associated with CVD (n = 3, phi = 0.15, P = 0.03).

CONCLUSIONS

Patients with asthma, CVD, on long-term corticosteroid inhalers or creams, or of Maori ethnicity need particular assessment to investigate herpes simplex as a possible cause of keratitis. Clinicians prescribing inhaled corticosteroids or topical corticosteroid creams should be aware of possible association with herpes simplex keratitis.

Is there any relationship between Chlamydophila pneumoniae and coronary atherosclerosis among Iranians?

Background:

Atherosclerosis is a coronary heart disease, andis the most common cause of death in the industrialized world. Some studies suggested that atherosclerosis may be triggered by infectious agents, mostly Chlamydophila pneumoniae. However, the role of C. pneumoniae in the pathogenesis of coronary atherosclerosis is still controversial.

Objectives:

This study was performed to evaluate whether there is a significant association between coronary artery atherosclerosis and C. pneumoniae by the polymerase chain reaction (PCR) method.

Materials and Methods:

This case-control study was carried out on formalin-fixed paraffin-embedded tissue biopsies of the coronary arteries obtained from 30 patients with coronary atherosclerosis and 30 subjects without atherosclerosis living in Northeast of Iran. All subjects' weight and height were determined, and the body mass index was calculated. We also reviewed the medical history and previous laboratory reports of patients. Deoxyribonucleic acid (DNA) was extracted, and C. pneumonia DNA was amplified and detected using PCR assay.

Results:

The age of the patients in the study group was from 18 to 50 years, and the male to female ratio was 5:1. Only oneout of the 30 coronary tissue samples had positive PCR for C. pneumoniae (3.3%), while it was negative for patients in the control group.

Conclusions:

This study showed that C. pneumoniae infection is not strongly associated with coronary artery atherosclerosis in Northeast of Iran.

Heat shock proteins: pathogenic role in atherosclerosis and potential therapeutic implications

Heat shock proteins (HSPs) are a highly conserved group of proteins that are constitutively expressed and function as molecular chaperones, aiding in protein folding and preventing the accumulation of misfolded proteins. In the arterial wall, HSPs have a protective role under normal physiologic conditions. In disease states, however, HSPs expressed on the vascular endothelial cell surface can act as targets for detrimental autoimmunity due to their highly conserved sequences. Developing therapeutic strategies for atherosclerosis based on HSPs is challenged by the need to balance such physiologic and pathologic roles of these proteins. This paper summarizes the role of HSPs in normal vascular wall processes as well as in the development and progression of atherosclerosis. The potential implications of HSPs in clinical therapies for atherosclerosis are also discussed.

Association between human parainfluenza virus type 1 and smoking history in patients with an abdominal aortic aneurysm

Several studies have suggested that infectious agents may induce the development of abdominal aortic aneurysms and/or accelerate their progression. The aim of this study was to evaluate the presence of the respiratory-transmitted viruses such as influenza A and B and parainfluenza type 1 genomes in bioptic fragments of abdominal aortic aneurysms. Furthermore, the association between viral infection and traditional risk factors for aneurysms was investigated employing multivariate logistic regression models. The genome of parainfluenza 1 was detected in 11 out of 57 patients with abdominal aortic aneurysm, influenza A only in one, whereas none of the specimens analyzed resulted positive for influenza B. After adjustment of age, gender, and clinical diagnosis, being current smokers was associated independently with parainfluenza 1 detection in aneurysms. The identification of parainfluenza 1 in aortic aneurysm biopsies supports previous observations of a possible role of viruses in the lesion development. Smoking, by interfering with the respiratory tract's ability to defend itself and predisposing to upper and lower respiratory tract infections may accelerate the onset and progression of abdominal aortic aneurysms.

Helicobacter species in the atherosclerotic plaques of patients with coronary artery disease

INTRODUCTION

Several epidemiological studies have proposed an association between Helicobacter pylori infection and coronary artery disease. In the current study, we aimed to evaluate the prevalence and relevance of H. pylori infection, using polymerase chain reaction (PCR) methods, in the coronary arterial wall of Iranian patients who have already undergone coronary bypass grafting (CABG).

METHODS

A total of 105 consecutive patients who underwent CABG at the Department of Cardiovascular Surgery of Baqiyatallah University of Medical Sciences were included in the study, and biopsy specimens from their coronary plaques were taken and analyzed using the PCR methods for detecting Helicobacter species (H Spp.). Fifty-three specimens from biopsies of the left internal mamillary artery in the same patients were also collected and tested.

RESULTS

H. Spp. PCR test result was positive for 31 (29.5%) specimens from coronary artery atherosclerotic plaques. Serologic test results also showed 25 (23.8%) positive cases for H. pylrori immunoglobulin A (IgA) and 56 (53.3%) positive for anti-H. pylori immunoglobulin G. None of the specimens from the mamillary artery were positive for H Spp. genome when it was evaluated using PCR (P<.0001). Patients with positive test result for H. pylori IgA were significantly more likely to have higher total cholesterol and low-density lipoprotein (LDL) levels than IgA-negative patients.

CONCLUSION

H Spp. infection replication in the coronary arterial wall is associated with atherosclerotic plaque formation. Seropositivity for H. pylori IgA may also enhance blood values of total cholesterol and LDL in these patients.

Cytomegalovirus localization in atherosclerotic plaques is associated with acute coronary syndromes: report of 105 patients

It has been shown that cytomegalovirus (CMV) is present in coronary atherosclerotic plaques, but the clinical relevance of this presence remains to be elucidated. In this study we sought to examine CMV infection in atherosclerosis patients defined by different methods and to identify the clinical significance of CMV replication in the atherosclerotic plaques. The study included 105 consecutive patients who were admitted to our department and underwent coronary artery bypass grafting (CABG) surgical interventions. Coronary atherosclerotic specimens as well as 53 specimens from the mamillary artery of these same patients were analyzed. Enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) methods were used for evaluations. The CMV PCR test result was positive for 28 (26.7%) of patients with coronary artery atherosclerosis. After adjusting for other risk factors, coronary artery disease patients with a history of acute coronary syndrome were more likely to be positive for CMV PCR test (P=0.027; odds ratio: 4.2; 95% CI: 1.18-15.0). They were also more likely to have a positive family history for cardiovascular diseases (CVD). This study confirms previous evidence about the replication of CMV virus in the atherosclerotic plaques of coronary arteries and brings clinical significance to this observation by showing a higher prevalence of acute coronary syndromes in those patients with CMV-infected plaques. Our study also suggests a familial vulnerability to CMV replication in the coronary artery walls.

Pathogens and atherosclerosis: update on the potential contribution of multiple infectious organisms to the pathogenesis of atherosclerosis

It is currently unclear what causes the chronic inflammation within atherosclerotic plaques. One emerging paradigm suggests that infection with bacteria and/or viruses can contribute to the pathogenesis of atherosclerosis either via direct infection of vascular cells or via the indirect effects of cytokines or acute phase proteins induced by infection at non-vascular sites. This paradigm has been supported by multiple epidemiological studies that have established positive associations between the risk of cardiovascular disease morbidity and mortality and markers of infection. It has also been supported by experimental studies showing an acceleration of the development of atherosclerosis following infection of hyperlipidaemic animal models. There are now a large number of different infectious agents that have been linked with an increased risk of cardiovascular disease. These include: Chlamydia pneumoniae, Porphyromonas gingivalis, Helicobacter pylori , influenza A virus, hepatitis C virus, cytomegalovirus, and human immunodeficiency virus. However, there are significant differences in the strength of the data supporting their association with cardiovascular disease pathogenesis. In some cases, the infectious agents are found within the plaques and viable organisms can be isolated suggesting a direct effect. In other cases, the association is entirely based on biomarkers. In the following review, we evaluate the strength of the data for individual or groups of pathogens with regard to atherosclerosis pathogenesis and their potential contribution by direct or indirect mechanisms and discuss whether the established associations are supportive of the infectious disease paradigm. We also discuss the failure of antibiotic trials and the question of persistent infection.

Search for genomic sequences of microbial agents in atherosclerotic plaques

Atherosclerosis is a complex, multifactorial disease. Several studies have reported a possible association between infection with microbial agents and atherogenesis. Chlamydia pneumoniae (C. pneumoniae), Herpes Simplex Virus 1 (HSV1), Human Cytomegalovirus (HCMV), and Epstein Barr Virus (EBV) have been widely investigated for their possible role in atherosclerosis development, but the results obtained to date are contradictory. The aim of our study is to search DNA of the aforementioned infectious agents by means of Quantitative Real Time PCR in atherosclerotic plaques from carotid arteries obtained from 17 patients. Genomic sequences of C. pneumoniae, HSV1, HCMV were not found in any atherosclerotic lesion. Therefore, our results do not support the hypothesis of an association between these infectious agents and atherosclerosis. Conversely, three patients were found to be positive for EBV DNA, thus indicating that, at least in a limited number of patients, EBV could play a role in atherogenesis.

Infectious atherosclerosis: is the hypothesis still alive? A clinically based approach to the dilemma

Among the multiple factors involved in the pathophysiology of heart disease, infections have been proposed to play a role in atherosclerosis with most of the available evidence implicating Chlamydia pneumonia, influenza virus and Mycoplasma pneumoniae. Based on a model case presentation, we speculate that in the absence of traditional risk factors and in the context of an ongoing respiratory infection caused by a pro-inflammatory pathogen (M. pneumoniae) along with a past positive serologic history for potentially proven atherogenic microorganism (C. pneumoniae) and infection may elicit potentially pathogenic events on vascular wall cells and leukocytes of atheromatous lesions, supporting the hypothesis that such infections may potentiate atherosclerotic cardiovascular disease (CVD).

Mycotic DNA in non-atherosclerotic aortic wall of coronary patients is associated with sICAM-1 expression

BACKGROUND

Atherosclerosis is currently being investigated as a chronic inflammatory process and the role of infectious agents is unclear. The presence of mycotic DNA in the wall of the non-atherosclerotic aorta of patients with coronary artery disease (CAD) and its association with levels of soluble intercellular adhesion molecule (sICAM)-1 expression was examined in the present study.

METHODS AND RESULTS

In 40 patients with CAD and a comparative group of 20 patients with aortic valve stenosis (AS) without CAD, specimens of the aortic wall were obtained during cardiac surgery. Mycotic DNA was analyzed by polymerase chain reaction (PCR) using a fungus-specific universal primer pair, ITS3 and ITS4, to amplify a portion of the 5.8S rDNA region, the entire ITS2 region and a portion of the 28S rDNA region, and using a species-specific primer pair, CALB1 and CALB2, to specifically amplify Candida (C.) albicans. The nested PCR method was performed to amplify the intergenic transcribed spacer regions of the rRNAs of Candida species. Before surgery the serum level of sICAM-1 was estimated. Mycotic DNA was detected in 48% of the CAD patients and in 40% of the AS patients, with C. albicans DNA in 58% and 100%, respectively (P>0.05). In CAD patients with a high level of sICAM-1, C. albicans DNA was found more frequently than in patients without elevated levels of sICAM-1 (P<0.05).

CONCLUSIONS

Mycotic DNA was found in the non-atherosclerotic aortic wall of CAD patients as well as in patients with AS. In the CAD patients C. albicans DNA was related to sICAM-1 expression.

Novel Helicobacter pylori therapeutic targets: the unusual suspects

Understanding the current status of the discovery and development of anti-Helicobacter therapies requires an overview of the searches for therapeutic targets performed to date. A summary is given of the very substantial body of work conducted in the quest to find Helicobacter pylori genes that could be suitable candidates for therapeutic intervention. The products of most of these genes perform metabolic functions, and others have roles in growth, cell motility and colonization. The genes identified as potential targets have been organized into three categories according to their degree of characterization. A short description and evaluation is provided of the main candidates in each category. Investigations of potential therapeutic targets have generated a wealth of information about the physiology and genetics of H. pylori, and its interactions with the host, but have yielded little by way of new therapies.

Helicobacters and extragastric diseases

For two decades, Helicobacter pylori has been considered as the culprit in many extragastric manifestations. However, for several of these supposed associations the hypothesis of an etiological role has not yet been fully investigated. This may be due to a series of factors linked to the epidemiological features of the studies and to the diseases investigated. This review attempts to highlight the main reported associations of H. pylori with extragastric manifestations during the last year. The most convincing data arise in the field of idiopathic thrombocytopenic purpura (ITP) and sideropenic anemia. Long-term follow-up studies have shown that 50% of subjects with ITP maintain a hematological response after H. pylori eradication. There is also growing evidence of the role of H. pylori in other diseases, including ischemic heart disease even though results are not conclusive.

Microarray technology in the study of genetic determinants of cardiovascular diseases

Microarray, a miniaturized glass slide or membrane with immobilized DNA probes, is a powerful tool for the analysis of mutations, gene expression and sequencing. This technique requires chip (glass slide or membrane) fabrication, preparation of probes and labelled targets, hybridization and data analysis. Microarrays give the possibility to evaluate a wide spectrum of candidate genes, to simultaneously observe interaction of genes, to detect polymorphisms within genes and identify therapeutic targets. Coronary artery disease being a major cause of death, is a disorder influenced by either genetic or environmental factors. Microarray analysis of gene expression can be used to identify genes involved in disease progression and in disease reduction. Chips also allow for the throughput and simultaneous analysis of a great variety of cell types such as cardiomyocytes, monocytes, macrophages, smooth muscle, endothelial, and fibroblasts and chemical mediators involved in cardiovascular disease pathology, their interactions and cumulative effects.

Extragastric manifestations of Helicobacter pylori infection: other Helicobacters

The finding that Helicobacter pylori is the main cause of gastritis and peptic ulcer disease has opened a new era in the gastrointestinal world. Today there is evidence that H. pylori may also play a role in different nongastric diseases, opening the new "extragastric manifestations of H. pylori infection" field. Concerning this, several studies have been published in the last year. The most convincing data arise from those investigating idiopathic thrombocytopenic purpura and sideropenic anemia, while there is also an increasing evidence for a possible association with atherosclerotic disease. Furthermore, the discovery of a number of other novel Helicobacter species has stimulated the research in different extragastric diseases, in which an infectious hypothesis is plausible. In particular, several species have been studied for a potential role in different liver and intestinal diseases with interesting findings.