Martin Petrek

Bio: Martin Petrek is an academic researcher from Palacký University, Olomouc. The author has contributed to research in topics: Population & Single-nucleotide polymorphism. The author has an hindex of 30, co-authored 137 publications receiving 2786 citations.

Phenotypes of organ involvement in sarcoidosis.

Abstract: Sarcoidosis is a highly variable, systemic granulomatous disease of hitherto unknown aetiology. The GenPhenReSa (Genotype–Phenotype Relationship in Sarcoidosis) project represents a European multicentre study to investigate the influence of genotype on disease phenotypes in sarcoidosis. The baseline phenotype module of GenPhenReSa comprised 2163 Caucasian patients with sarcoidosis who were phenotyped at 31 study centres according to a standardised protocol. From this module, we found that patients with acute onset were mainly female, young and of Scadding type I or II. Female patients showed a significantly higher frequency of eye and skin involvement, and complained more of fatigue. Based on multidimensional correspondence analysis and subsequent cluster analysis, patients could be clearly stratified into five distinct, yet undescribed, subgroups according to predominant organ involvement: 1) abdominal organ involvement, 2) ocular–cardiac–cutaneous–central nervous system disease involvement, 3) musculoskeletal–cutaneous involvement, 4) pulmonary and intrathoracic lymph node involvement, and 5) extrapulmonary involvement. These five new clinical phenotypes will be useful to recruit homogenous cohorts in future biomedical studies.

Serum levels of the MCP-1 chemokine in patients with ischemic stroke and myocardial infarction.

Abstract: Chemokine-driven migration of inflammatory cells has been implicated in pathogenesis of atherosclerosis-associated conditions such as ischemic stroke and myocardial infarction. In this study, a candidate chemokine, monocyte chemoattractant protein (MCP)-1, was investigated in patients with both aforementioned manifestations of atheroslerotic inflammation. MCP-1 levels in serum were determined by ELISA in 40 healthy, control subjects (C), 40 patients with ischemic stroke (IS), and in 64 patients with myocardial infarction (MI). Statistical analysis utilised Mann-Whitney test, Fisher's exact test, and Spearman's rank correlation (P < .05). In comparison to control subjects (C; median/interquartile range: 239/126 pg/mL), MCP-1 serum levels were increased in both investigated patient cohorts (IS: 384/370, P < .001; MI: 360/200, P < .002). There was a substantial variability of MCP-1 serum levels, especially in the IS group. No relationship was observed between chemokine levels and atherosclerosis risk factors (hypertension, diabetes, smoking, and alcohol consumption), and MCP-1 was also not related to age or gender. Elevation of MCP-1 in circulation of patients with atherosclerosis-associated complications implicates this CC chemokine ligand (CCL)2 in inflammatory processes, which contribute to pathogenesis of myocardial infarction and ischemic stroke. Further investigations, including patient stratification, are however necessary to evaluate if MCP-1 can be utilised for clinical management of patients with these diseases.

CC chemokine receptor gene polymorphisms in Czech patients with pulmonary sarcoidosis

Abstract: Genes for the chemokine receptors CCR5 and CCR2 are characterized by polymorphisms resulting in a nonfunctional receptor expression. Ligands for CCR2 and CCR5 (chemokines monocyte chemotactic protein-1 [MCP-1] and RANTES) are implicated in the pathogenesis of sarcoidosis. We have, therefore, analyzed polymorphisms of CCR5 (32-bp deletion in CCR5 gene [ D 32]) and of CCR2 (replacement of valine by isoleucine in CCR2 gene [64I]) in 66 Czech patients with sarcoidosis in comparison with a representative sample of Czech normal population. The frequencies of CCR5 D 32 and CCR2-64I polymorphisms in patients with sarcoidosis were different from that in control subjects. CCR5 D 32 allelic frequency was significantly increased in patients. By contrast, the CCR2-64I allele was more frequent in control subjects; however, the difference did not attain significance. Interestingly, the CCR5 D 32 allele was associated with clinically more apparent disease: it was present in 39.1% of pa

Involvement of microRNAs in physiological and pathological processes in the lung

Abstract: To date, at least 900 different microRNA (miRNA) genes have been discovered in the human genome. These short, single-stranded RNA molecules originate from larger precursor molecules that fold to produce hairpin structures, which are subsequently processed by ribonucleases Drosha/Pasha and Dicer to form mature miRNAs. MiRNAs play role in the posttranscriptional regulation of about one third of human genes, mainly via degradation of target mRNAs. Whereas the target mRNAs are often involved in the regulation of diverse physiological processes ranging from developmental timing to apoptosis, miRNAs have a strong potential to regulate fundamental biological processes also in the lung compartment. However, the knowledge of the role of miRNAs in physiological and pathological conditions in the lung is still limited. This review, therefore, summarizes current knowledge of the mechanism, function of miRNAs and their contribution to lung development and homeostasis. Besides the involvement of miRNAs in pulmonary physiological conditions, there is evidence that abnormal miRNA expression may lead to pathological processes and development of various pulmonary diseases. Next, the review describes current state-of-art on the miRNA expression profiles in smoking-related diseases including lung cancerogenesis, in immune system mediated pulmonary diseases and fibrotic processes in the lung. From the current research it is evident that miRNAs may play role in the posttranscriptional regulation of key genes in human pulmonary diseases. Further studies are, therefore, necessary to explore miRNA expression profiles and their association with target mRNAs in human pulmonary diseases.

Human leukocyte antigen-DRB1 position 11 residues are a common protective marker for sarcoidosis.

Abstract: Genetic factors, in particular human leukocyte antigens (HLAs) are important determinants of susceptibility to sarcoidosis, a chronic granulomatous disease of undetermined etiology. To clarify the role of HLA in sarcoidosis we determined HLA-DR and -DQ alleles in case-control samples from three European populations (United Kingdom, Czech, and Polish) and compared these results with those published for three additional populations (Italian, Japanese, and Scandinavian) to determine whether the HLA-DR and/or -DQ alleles act as ethnic-dependent, or ethnic-independent modifiers of disease risk. Although variations were apparent in the alleles associated with susceptibility, reductions in the frequency of alleles associated with protection were remarkably consistent in the six populations. Previously detected associations between single-nucleotide polymorphisms at the TAP2 locus and sarcoidosis were shown to be due to linkage disequilibrium with the HLA-DR locus. The protective HLA-DR alleles, which encode the DR1 and DR4 antigens, were found to share characteristic small hydrophobic residues at position 11, which were replaced by small hydrophilic residues in the remaining, nonprotective, HLA-DR alleles. This residue position is within a pocket of the HLA-DR complex antigen binding groove (designated P6), where it is the only variable amino acid and therefore determines the peptide binding preferences of this pocket. A highly significant reduction in the frequency of individuals carrying HLA-DR alleles with a hydrophobic residue at position 11 was observed in the sarcoidosis cases in the three populations we examined. This suggests this HLA-DR residue is an important protective marker in sarcoidosis.

Monocyte chemoattractant protein-1 (MCP-1): an overview.

Abstract: Chemokines constitute a family of chemoattractant cytokines and are subdivided into four families on the basis of the number and spacing of the conserved cysteine residues in the N-terminus of the protein. Chemokines play a major role in selectively recruiting monocytes, neutrophils, and lymphocytes, as well as in inducing chemotaxis through the activation of G-protein-coupled receptors. Monocyte chemoattractant protein-1 (MCP-1/CCL2) is one of the key chemokines that regulate migration and infiltration of monocytes/macrophages. Both CCL2 and its receptor CCR2 have been demonstrated to be induced and involved in various diseases. Migration of monocytes from the blood stream across the vascular endothelium is required for routine immunological surveillance of tissues, as well as in response to inflammation. This review will discuss these biological processes and the structure and function of CCL2.

An Official American Thoracic Society/European Respiratory Society Statement: Update of the International Multidisciplinary Classification of the Idiopathic Interstitial Pneumonias

Abstract: Background: In 2002 the American Thoracic Society/European Respiratory Society (ATS/ERS) classification of idiopathic interstitial pneumonias (IIPs) defined seven specific entities, and provided standardized terminology and diagnostic criteria. In addition, the historical “gold standard” of histologic diagnosis was replaced by a multidisciplinary approach. Since 2002 many publications have provided new information about IIPs.Purpose: The objective of this statement is to update the 2002 ATS/ERS classification of IIPs.Methods: An international multidisciplinary panel was formed and developed key questions that were addressed through a review of the literature published between 2000 and 2011.Results: Substantial progress has been made in IIPs since the previous classification. Nonspecific interstitial pneumonia is now better defined. Respiratory bronchiolitis–interstitial lung disease is now commonly diagnosed without surgical biopsy. The clinical course of idiopathic pulmonary fibrosis and nonspecific inte...

European Position Paper on Rhinosinusitis and Nasal Polyps 2020

Abstract: The European Position Paper on Rhinosinusitis and Nasal Polyps 2020 is the update of similar evidence based position papers published in 2005 and 2007 and 2012. The core objective of the EPOS2020 guideline is to provide revised, up-to-date and clear evidence-based recommendations and integrated care pathways in ARS and CRS. EPOS2020 provides an update on the literature published and studies undertaken in the eight years since the EPOS2012 position paper was published and addresses areas not extensively covered in EPOS2012 such as paediatric CRS and sinus surgery. EPOS2020 also involves new stakeholders, including pharmacists and patients, and addresses new target users who have become more involved in the management and treatment of rhinosinusitis since the publication of the last EPOS document, including pharmacists, nurses, specialised care givers and indeed patients themselves, who employ increasing self-management of their condition using over the counter treatments. The document provides suggestions for future research in this area and offers updated guidance for definitions and outcome measurements in research in different settings. EPOS2020 contains chapters on definitions and classification where we have defined a large number of terms and indicated preferred terms. A new classification of CRS into primary and secondary CRS and further division into localized and diffuse disease, based on anatomic distribution is proposed. There are extensive chapters on epidemiology and predisposing factors, inflammatory mechanisms, (differential) diagnosis of facial pain, allergic rhinitis, genetics, cystic fibrosis, aspirin exacerbated respiratory disease, immunodeficiencies, allergic fungal rhinosinusitis and the relationship between upper and lower airways. The chapters on paediatric acute and chronic rhinosinusitis are totally rewritten. All available evidence for the management of acute rhinosinusitis and chronic rhinosinusitis with or without nasal polyps in adults and children is systematically reviewed and integrated care pathways based on the evidence are proposed. Despite considerable increases in the amount of quality publications in recent years, a large number of practical clinical questions remain. It was agreed that the best way to address these was to conduct a Delphi exercise . The results have been integrated into the respective sections. Last but not least, advice for patients and pharmacists and a new list of research needs are included. The full document can be downloaded for free on the website of this journal: http://www.rhinologyjournal.com.

Sarcoidosis

Abstract: 结节病易误诊,据王洪武等~([1])收集国内18篇关于此病误诊的文献,误诊率高达63.2%,当然有误诊就会有误治,如孙永昌等~([2])报道26例结节病在影像学检查诊断的第一印象中拟诊结核5例,其中就有2例完成规范的抗结核治疗,为此应引起临床对本病诊治的重视。