Prevalence and genotype distribution of cervical human papillomavirus (HPV) among women in urban Tianjin, China.

To investigate the prevalence and genotype distribution of human papillomavirus (HPV) infection among women in urban Tianjin, China. A cervical cancer screening program for 2,000 women aged 21-65 years old was performed in urban Tianjin from April to October in 2013. The program included ThinPrep cytologic tests (TCT), HPV DNA detection and genotyping using nested polymerase chain reaction (PCR) combined with Pyrosequencing technology. Colposcopy examination and biopsy were needed if TCT reported greater or equal atypical cells of undetermined significance (ASCUS). One thousand nine hundred seventy-eight women were enrolled in the final study, 14.71% (291/1,978) of women were tested HPV positive. Of HPV-positive specimens, 248 (85.22%) and 43 (14.78%) were infected with high- and low-risk HPV genotypes, respectively. Twenty-eight types of HPV were detected in all, the most frequently detected types were HPV16, 58, 18, and 66 orderly. The single infection rate was 92.28% among HPV-positive samples while the multiple infection rate was 7.72%. Among multiple infection models, HPV16 was the most common type co-infection with other types. This study is, to our knowledge, the first population-based survey to provide data on HPV infection and genotype distribution among women in urban Tianjin, China. There was a high prevalence of HPV infection in this area, and HPV16, 58, 18, 66 were the most frequently detected genotypes. Our study provide important information regarding the necessity of early cervical cancer screenings and prophylactic HPV vaccinations, and the knowledge of HPV distribution can also inform us about the HPV ecological change after the vaccination.

Making sense of intratumor genetic heterogeneity: altered frequency of androgen receptor CAG repeat length variants in breast cancer tissues.

To examine the significance of intratumor genetic heterogeneity (ITGH) of the androgen receptor (AR) gene in breast cancer, patient-matched samples of laser capture microdissected breast tumor cells, adjacent normal breast epithelia cells, and peripheral blood leukocytes were sequenced using a novel next generation sequencing protocol. This protocol measured the frequency of distribution of a variable AR CAG repeat length, a functional polymorphism associated with breast cancer risk. All samples exhibited some degree of ITGH with up to 30 CAG repeat length variants identified. Each type of tissue exhibited a different distribution profile of CAG repeat lengths with substantial differences in the frequencies of zero and 18-25 CAG AR variants. Tissue differences in the frequency of ARs with each of these CAG repeat lengths were significant as measured by paired, twin t-tests. These results suggest that preferential selection of 18-25 CAG repeat length variants in breast tumors may be associated with breast cancer, and support the observation that shorter CAG repeats may protect against breast cancer. They also suggest that merely identifying variant genes will be insufficient to determine the critical mutational events of oncogenesis, which will require measuring the frequency of distribution of mutations within cancerous and matching normal tissues.

Deep sequencing of the hepatitis B virus in hepatocellular carcinoma patients reveals enriched integration events, structural alterations and sequence variations.

Chronic hepatitis B virus (HBV) infection is epidemiologically associated with hepatocellular carcinoma (HCC), but its role in HCC remains poorly understood due to technological limitations. In this study, we systematically characterize HBV in HCC patients. HBV sequences were enriched from 48 HCC patients using an oligo-bead-based strategy, pooled together and sequenced using the FLX-Genome-Sequencer. In the tumors, preferential integration of HBV into promoters of genes (P < 0.001) and significant enrichment of integration into chromosome 10 (P < 0.01) were observed. Integration into chromosome 10 was significantly associated with poorly differentiated tumors (P < 0.05). Notably, in the tumors, recurrent integration into the promoter of the human telomerase reverse transcriptase (TERT) gene was found to correlate with increased TERT expression. The preferred region within the HBV genome involved in integration and viral structural alteration is at the 3'-end of hepatitis B virus X protein (HBx), where viral replication/transcription initiates. Upon integration, the 3'-end of the HBx is often deleted. HBx-human chimeric transcripts, the most common type of chimeric transcripts, can be expressed as chimeric proteins. Sequence variation resulting in non-conservative amino acid substitutions are commonly observed in HBV genome. This study highlights HBV as highly mutable in HCC patients with preferential regions within the host and virus genome for HBV integration/structural alterations.

Although divergent in residues of the peptide binding site, conserved chimpanzee Patr-AL and polymorphic human HLA-A*02 have overlapping peptide-binding repertoires.

Patr-AL is an expressed, non-polymorphic MHC class I gene carried by ∼50% of chimpanzee MHC haplotypes. Comparing Patr-AL(+) and Patr-AL(-) haplotypes showed Patr-AL defines a unique 125-kb genomic block flanked by blocks containing classical Patr-A and pseudogene Patr-H. Orthologous to Patr-AL are polymorphic orangutan Popy-A and the 5' part of human pseudogene HLA-Y, carried by ∼10% of HLA haplotypes. Thus, the AL gene alternatively evolved in these closely related species to become classical, nonclassical, and nonfunctional. Although differing by 30 aa substitutions in the peptide-binding α(1) and α(2) domains, Patr-AL and HLA-A*0201 bind overlapping repertoires of peptides; the overlap being comparable with that between the A*0201 and A*0207 subtypes differing by one substitution. Patr-AL thus has the A02 supertypic peptide-binding specificity. Patr-AL and HLA-A*0201 have similar three-dimensional structures, binding peptides in similar conformation. Although comparable in size and shape, the B and F specificity pockets of Patr-AL and HLA-A*0201 differ in both their constituent residues and contacts with peptide anchors. Uniquely shared by Patr-AL, HLA-A*0201, and other members of the A02 supertype are the absence of serine at position 9 in the B pocket and the presence of tyrosine at position 116 in the F pocket. Distinguishing Patr-AL from HLA-A*02 is an unusually electropositive upper face on the α(2) helix. Stimulating PBMCs from Patr-AL(-) chimpanzees with B cells expressing Patr-AL produced potent alloreactive CD8 T cells with specificity for Patr-AL and no cross-reactivity toward other MHC class I molecules, including HLA-A*02. In contrast, PBMCs from Patr-AL(+) chimpanzees are tolerant of Patr-AL.

High throughput sequencing reveals a complex pattern of dynamic interrelationships among human T cell subsets.

Developing T cells face a series of cell fate choices in the thymus and in the periphery. The role of the individual T cell receptor (TCR) in determining decisions of cell fate remains unresolved. The stochastic/selection model postulates that the initial fate of the cell is independent of TCR specificity, with survival dependent on additional TCR/coreceptor "rescue" signals. The "instructive" model holds that cell fate is initiated by the interaction of the TCR with a cognate peptide-MHC complex. T cells are then segregated on the basis of TCR specificity with the aid of critical coreceptors and signal modulators [Chan S, Correia-Neves M, Benoist C, Mathis (1998) Immunol Rev 165: 195-207]. The former would predict a random representation of individual TCR across divergent T cell lineages whereas the latter would predict minimal overlap between divergent T cell subsets. To address this issue, we have used high-throughput sequencing to evaluate the TCR distribution among key T cell developmental and effector subsets from a single donor. We found numerous examples of individual subsets sharing identical TCR sequence, supporting a model of a stochastic process of cell fate determination coupled with dynamic patterns of clonal expansion of T cells bearing the same TCR sequence among both CD4(+) and CD8+ populations.

Development of a targeted amplicon sequencing method for genotyping Cyclospora cayetanensis from fresh produce and clinical samples with enhanced genomic resolution and sensitivity.

Outbreaks of cyclosporiasis, an enteric illness caused by the parasite Cyclospora cayetanensis, have been associated with consumption of various types of fresh produce. Although a method is in use for genotyping C. cayetanensis from clinical specimens, the very low abundance of C. cayetanensis in food and environmental samples presents a greater challenge. To complement epidemiological investigations, a molecular surveillance tool is needed for use in genetic linkage of food vehicles to cyclosporiasis illnesses, estimation of the scope of outbreaks or clusters of illness, and determination of geographical areas involved. We developed a targeted amplicon sequencing (TAS) assay that incorporates a further enrichment step to gain the requisite sensitivity for genotyping C. cayetanensis contaminating fresh produce samples. The TAS assay targets 52 loci, 49 of which are located in the nuclear genome, and encompasses 396 currently known SNP sites. The performance of the TAS assay was evaluated using lettuce, basil, cilantro, salad mix, and blackberries inoculated with C. cayetanensis oocysts. A minimum of 24 markers were haplotyped even at low contamination levels of 10 oocysts in 25 g leafy greens. The artificially contaminated fresh produce samples were included in a genetic distance analysis based on haplotype presence/absence with publicly available C. cayetanensis whole genome sequence assemblies. Oocysts from two different sources were used for inoculation, and samples receiving the same oocyst preparation clustered together, but separately from the other group, demonstrating the utility of the assay for genetically linking samples. Clinical fecal samples with low parasite loads were also successfully genotyped. This work represents a significant advance in the ability to genotype C. cayetanensis contaminating fresh produce along with greatly expanding the genomic diversity included for genetic clustering of clinical specimens.

Whole-genome sequencing of the efficient industrial fuel-ethanol fermentative Saccharomyces cerevisiae strain CAT-1.

The Saccharomyces cerevisiae strains widely used for industrial fuel-ethanol production have been developed by selection, but their underlying beneficial genetic polymorphisms remain unknown. Here, we report the draft whole-genome sequence of the S. cerevisiae strain CAT-1, which is a dominant fuel-ethanol fermentative strain from the sugarcane industry in Brazil. Our results indicate that strain CAT-1 is a highly heterozygous diploid yeast strain, and the ~12-Mb genome of CAT-1, when compared with the reference S228c genome, contains ~36,000 homozygous and ~30,000 heterozygous single nucleotide polymorphisms, exhibiting an uneven distribution among chromosomes due to large genomic regions of loss of heterozygosity (LOH). In total, 58 % of the 6,652 predicted protein-coding genes of the CAT-1 genome constitute different alleles when compared with the genes present in the reference S288c genome. The CAT-1 genome contains a reduced number of transposable elements, as well as several gene deletions and duplications, especially at telomeric regions, some correlated with several of the physiological characteristics of this industrial fuel-ethanol strain. Phylogenetic analyses revealed that some genes were likely associated with traits important for bioethanol production. Identifying and characterizing the allelic variations controlling traits relevant to industrial fermentation should provide the basis for a forward genetics approach for developing better fermenting yeast strains.

Six RNA viruses and forty-one hosts: viral small RNAs and modulation of small RNA repertoires in vertebrate and invertebrate systems.

We have used multiplexed high-throughput sequencing to characterize changes in small RNA populations that occur during viral infection in animal cells. Small RNA-based mechanisms such as RNA interference (RNAi) have been shown in plant and invertebrate systems to play a key role in host responses to viral infection. Although homologs of the key RNAi effector pathways are present in mammalian cells, and can launch an RNAi-mediated degradation of experimentally targeted mRNAs, any role for such responses in mammalian host-virus interactions remains to be characterized. Six different viruses were examined in 41 experimentally susceptible and resistant host systems. We identified virus-derived small RNAs (vsRNAs) from all six viruses, with total abundance varying from "vanishingly rare" (less than 0.1% of cellular small RNA) to highly abundant (comparable to abundant micro-RNAs "miRNAs"). In addition to the appearance of vsRNAs during infection, we saw a number of specific changes in host miRNA profiles. For several infection models investigated in more detail, the RNAi and Interferon pathways modulated the abundance of vsRNAs. We also found evidence for populations of vsRNAs that exist as duplexed siRNAs with zero to three nucleotide 3' overhangs. Using populations of cells carrying a Hepatitis C replicon, we observed strand-selective loading of siRNAs onto Argonaute complexes. These experiments define vsRNAs as one possible component of the interplay between animal viruses and their hosts.

A comprehensive HPV-STI NGS assay for detection of 29 HPV types and 14 non-HPV sexually transmitted infections.

BACKGROUND: Sexually transmitted infections (STIs) are prevalent throughout the world and impose a significant burden on individual health and public health systems. Missed diagnosis and late treatment of STIs can lead to serious complications such as infertility and cervical cancer. Although sexually transmitted co-infections are common, most commercial assays target one or a few STIs. The HPV-STI ChapterDx Next Generation Sequencing (NGS) assay detects and quantifies 29 HPVs and 14 other STIs in a single-tube and single-step PCR reaction and can be applied to tens to thousands of samples in a single sequencing run. METHODS: A cohort of 274 samples, previously analyzed by conventional cytology/histology and Roche cobas HPV Test, were analyzed by ChapterDx HPV-STI NGS assay for detection of 43 HPV and STI. A set of 43 synthetic control DNA fragments for 43 HPV and STI were developed to evaluate the limit of detection, specificity, and sensitivity of ChapterDx HPV-STI NGS assay. RESULTS: The assay was evaluated in this study, and the limit of detection was 100% at 50 copies for all targets, and 100%, 96%, 88% at 20 copies for 34, 8, and 1 target, respectively. The performance of this assay has been compared to Roche cobas HPV test, showing an overall agreement of 97.5% for hr-HPV, and 98.5% for both, HPV16 and HPV18. The assay also detected all HPV-infected CIN2/3 with 100% agreement with Roche cobas HPV results. Moreover, several co-infections with non-HPV STIs, such as C. trachomatis, T. vaginalis, M. genitalium, and HSV2 were identified. CONCLUSIONS: The ChapterDx HPV-STI NGS assay is a user-friendly, easy to automate and cost-efficient assay, which provides accurate and comprehensive results for a wide spectrum of HPVs and STIs.

Navigating the Pandemic Response Life Cycle: Molecular Diagnostics and Immunoassays in the Context of COVID-19 Management.

Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To counter COVID-19 spreading, an infrastructure to provide rapid and thorough molecular diagnostics and serology testing is the cornerstone of outbreak and pandemic management. We hereby review the clinical insights with regard to using molecular tests and immunoassays in the context of COVID-19 management life cycle: the preventive phase, the preparedness phase, the response phase and the recovery phase. The spatial and temporal distribution of viral RNA, antigens and antibodies during human infection is summarized to provide a biological foundation for accurate detection of the disease. We shared the lessons learned and the obstacles encountered during real world high-volume screening programs. Clinical needs are discussed to identify existing technology gaps in these tests. Leverage technologies, such as engineered polymerases, isothermal amplification, and direct amplification from complex matrices may improve the productivity of current infrastructure, while emerging technologies like CRISPR diagnostics, visual end point detection, and PCR free methods for nucleic acid sensing may lead to at-home tests. The lessons learned, and innovations spurred from the COVID-19 pandemic could upgrade our global public health infrastructure to better combat potential outbreaks in the future.

Pyrosequencing enhancement for better detection limit and sequencing homopolymers.

Pyrosequencing is a DNA sequencing technique based on sequencing-by-synthesis enabling rapid and real-time sequence determination. Although ample genomic research has been undertaken using pyrosequencing, the requirement of relatively high amount of DNA template and the difficulty in sequencing the homopolymeric regions limit its key advantages in the applications directing towards clinical research. In this study, we demonstrate that pyrosequencing on homopolymeric regions with 10 identical nucleotides can be successfully performed with optimal amount of DNA (0.3125-5 pmol) immobilized on conventional non-porous Sepharose beads. We also validate that by using porous silica beads, the sequencing signal increased 3.5-folds as compared to that produced from same amount of DNA immobilized on solid Sepharose beads. Our results strongly indicate that with optimized quantity of DNA and suitable solid support, the performance of pyrosequencing on homopolymeric regions and its detection limit has been significantly improved.

Minority human immunodeficiency virus type 1 variants in antiretroviral-naive persons with reverse transcriptase codon 215 revertant mutations.

T215 revertant mutations such as T215C/D/E/S that evolve from the nucleoside reverse transcriptase (RT) inhibitor mutations T215Y/F have been found in about 3% of human immunodeficiency virus type 1 (HIV-1) isolates from newly diagnosed HIV-1-infected persons. We used a newly developed sequencing method-ultradeep pyrosequencing (UDPS; 454 Life Sciences)--to determine the frequency with which T215Y/F or other RT inhibitor resistance mutations could be detected as minority variants in samples from untreated persons that contain T215 revertants ("revertant" samples) compared with samples from untreated persons that lack such revertants ("control" samples). Among the 22 revertant and 29 control samples, UDPS detected a mean of 3.8 and 4.8 additional RT amino acid mutations, respectively. In 6 of 22 (27%) revertant samples and in 4 of 29 control samples (14%; P = 0.4), UDPS detected one or more RT inhibitor resistance mutations. T215Y or T215F was not detected in any of the revertant or control samples; however, 4 of 22 revertant samples had one or more T215 revertants that were detected by UDPS but not by direct PCR sequencing. The failure to detect viruses with T215Y/F in the 22 revertant samples in this study may result from the overwhelming replacement of transmitted T215Y variants by the more fit T215 revertants or from the primary transmission of a T215 revertant in a subset of persons with T215 revertants.

Viral population estimation using pyrosequencing.

The diversity of virus populations within single infected hosts presents a major difficulty for the natural immune response as well as for vaccine design and antiviral drug therapy. Recently developed pyrophosphate-based sequencing technologies (pyrosequencing) can be used for quantifying this diversity by ultra-deep sequencing of virus samples. We present computational methods for the analysis of such sequence data and apply these techniques to pyrosequencing data obtained from HIV populations within patients harboring drug-resistant virus strains. Our main result is the estimation of the population structure of the sample from the pyrosequencing reads. This inference is based on a statistical approach to error correction, followed by a combinatorial algorithm for constructing a minimal set of haplotypes that explain the data. Using this set of explaining haplotypes, we apply a statistical model to infer the frequencies of the haplotypes in the population via an expectation-maximization (EM) algorithm. We demonstrate that pyrosequencing reads allow for effective population reconstruction by extensive simulations and by comparison to 165 sequences obtained directly from clonal sequencing of four independent, diverse HIV populations. Thus, pyrosequencing can be used for cost-effective estimation of the structure of virus populations, promising new insights into viral evolutionary dynamics and disease control strategies.

A pyrosequencing-tailored nucleotide barcode design unveils opportunities for large-scale sample multiplexing.

Multiplexed high-throughput pyrosequencing is currently limited in complexity (number of samples sequenced in parallel), and in capacity (number of sequences obtained per sample). Physical-space segregation of the sequencing platform into a fixed number of channels allows limited multiplexing, but obscures available sequencing space. To overcome these limitations, we have devised a novel barcoding approach to allow for pooling and sequencing of DNA from independent samples, and to facilitate subsequent segregation of sequencing capacity. Forty-eight forward-reverse barcode pairs are described: each forward and each reverse barcode unique with respect to at least 4 nt positions. With improved read lengths of pyrosequencers, combinations of forward and reverse barcodes may be used to sequence from as many as n(2) independent libraries for each set of 'n' forward and 'n' reverse barcodes, for each defined set of cloning-linkers. In two pilot series of barcoded sequencing using the GS20 Sequencer (454/Roche), we found that over 99.8% of obtained sequences could be assigned to 25 independent, uniquely barcoded libraries based on the presence of either a perfect forward or a perfect reverse barcode. The false-discovery rate, as measured by the percentage of sequences with unexpected perfect pairings of unmatched forward and reverse barcodes, was estimated to be <0.005%.

Does HPV-status 6-12 months after treatment of high grade dysplasia in the uterine cervix predict long term recurrence?

BACKGROUND: Women once treated for high grade cervical dysplasia have a high long term risk for developing new dysplasia or cancer. OBJECTIVES: To investigate if human papilloma virus (HPV)-negativity after treatment of cervical dysplasia reduces the need for frequent long term follow up. DESIGN: Case/control study based on archival smears. METHODS: Women with cervical intraepithelial neoplasi (CIN)2-3, treated for dysplasia and with recurrence of CIN2+ more than 2 years after treatment were compared with controls without recurrence, matched for age and date of treatment. High risk-HPV-DNA were analysed with PCR from two archival smears per woman. Mean follow up time was 14.6 years. RESULTS: 24% (45/189) of cases and 11% (43/378) of controls were HPV-positive in any of two smears. Odds ratio (OR)=2.5 (1.6-3.8). CONCLUSION: HPV-status 6-12 months after treatment of high grade dysplasia is of limited value for the design of long term follow up.

Molecular characterization of Neisseria gonorrhoeae identifies transmission and resistance of one ciprofloxacin-resistant strain.

A highly discriminative and objective genetic characterization of N. gonorrhoeae, which increases our knowledge of strain populations in different geographic areas, is crucial for the development of improved control measures. In the present study, conventional phenotypic characterization and genetic characterization by means of pulsed-field gel electrophoresis (PFGE), sequencing of the entire porB gene, N. gonorrhoeae multiantigen sequence typing (NG-MAST), and pyrosequencing of a quinolone resistance determining region (QRDR) of the gyrA gene of Swedish ciprofloxacin-resistant N. gonorrhoeae serovar IB-10 isolates (n=45) were performed. The genetic characterization identified one widely spread ciprofloxacin-resistant N. gonorrhoeae ST147 strain. In addition, isolates with slightly different genetic characteristics, which presumably reflect the ongoing evolution only, were also identified. All the isolates contained single nucleotide polymorphisms in QRDR of the gyrA gene that are highly correlated with ciprofloxacin resistance. Consequently, comprehensive characterization identified the first confirmed large domestic transmission, mainly among young heterosexuals, of one ciprofloxacin-resistant N. gonorrhoeae strain in Swedish society during 2002-2003. In conclusion, a precise, i.e. genetic, characterization for identification of individual strains is a very valuable support to the crucial active surveillance of the epidemiological characteristics and the antibiotic susceptibility of N. gonorrhoeae in the effective treatment of gonorrhoea.

Human papillomavirus (HPV), DNA aberrations and cell cycle progression in anal squamous cell carcinoma patients.

UNLABELLED: Human papillomavirus (HPV) infections of the genital tract are sexually transmitted and prevalent worldwide. In this study, the role of HPV in 72 patients with anal squamous cell carcinoma was investigated. PATIENTS AND METHODS: Polymerase chain reaction (PCR) in combination with in situ hybridization was used to identify HPV-DNA in the patients' biopsies. The HPV typing was conducted by pyrosequencing. Cell cycle and DNA content were analysed by cytometry. RESULTS: Ninety percent of the carcinoma biopsies carried high-risk oncogenic HPV in their malignant cells. Eighty-one percent of these demonstrated a single infection with HPV16, 18 or 33 and 19% were double infected with HPV16 and HPV18. Accumulations of viral genes were seen at the necrotic area of the tumours. The HPV genome in the tumour cell influenced significantly the host cell cycle progression, but not DNA aberrations. Within these patients, HPVstatus in the malignant cells was not found to be associated with patient survival time. CONCLUSION: High-risk oncogenic HPV may play an important role in the initiation of host cell proliferation in anal squamous cell carcinoma. However, infection with HPV may not have any direct influence itself on the clinical outcome of these patients considering the treatments currently available.

MHC2TA single nucleotide polymorphism and genetic risk for autoimmune adrenal insufficiency.

CONTEXT: The polymorphism of class II HLA genes modulates the genetic risk for several endocrine autoimmune diseases. The constitutive class II expression on antigen-presenting cells is under the control of the MHC class II transactivator, encoded by the MHC2TA gene, which is mapped to chromosome 16p13. The MHC2TA -168 A-->G single nucleotide polymorphism (rs3087456) has been suggested to confer susceptibility to some autoimmune diseases. DESIGN: With the aim of testing whether this MHC2TA single nucleotide polymorphism is independently associated with autoimmune Addison's disease (AAD) and/or modulates the genetic risk conferred by DRB1-DQA1-DQB1 haplotypes, we analyzed DNA samples from 128 AAD patients and 406 healthy control subjects from continental Italy. RESULTS: Frequency of allele G of MHC2TA was significantly increased among AAD patients (39% alleles), compared with 29% in healthy controls (P = 0.003). Similarly, the frequency of AG+GG genotypes was significantly higher among AAD patients than among healthy control subjects, in both a codominant (P = 0.012) and a G-dominant model (P = 0.018). Multivariate logistic regression analysis showed that MHC2TA AG+GG continued to be positively associated with genetic risk for AAD (P = 0.028, odds ratio = 1.72, 95% confidence interval = 1.06-2.78), after correction for DRB1*03-DQA1*0501-DQB1*0201, DRB1*04 (not 0403)-DQA1*0301-DQB1*0302 and DRB1*0403. Similar results were obtained when the number of G alleles was included in the model (P = 0.004; odds ratio = 1.65, 95% confidence interval = 1.17-2.32). CONCLUSIONS: Our study provides the first demonstration of the association of the polymorphism of the MHC2TA gene with genetic risk for AAD that appears to be independent from the well-known association with the polymorphism of HLA class II genes.

Influence of eotaxin 67G>A polymorphism on plasma eotaxin concentrations in myocardial infarction survivors and healthy controls.

Eotaxin (CCL11) is a CC chemokine, whose systemic levels might be associated with coronary artery disease (CAD) and genetic variants predispose to the myocardial infarction (MI). However, the relationship between eotaxin genetic variants and plasma concentrations in CAD patients is still incompletely characterized. We genotyped 311 patients, who survived first MI and 338 controls for a 67G>A single nucleotide polymorphism in the eotaxin gene. By measuring plasma eotaxin concentrations in those subjects we related the former to the presence of 67G>A SNP. There were no differences in eotaxin genotype frequencies between patients and controls. Patient G/G carriers had higher circulating eotaxin levels compared both to G/A and A/A patients (P=0.046) and G/G controls (P=0.028), which might indicate the influence of additional factors (e.g. inflammatory mediators) on eotaxin secretion in those patients. At the same time, eotaxin levels did not differ between patients and controls irrespective of the 67G>A SNP variants they carried. There were no associations between plasma eotaxin levels, biochemical indicators of CAD and the degree of coronary artery stenosis in post-MI patients. Interestingly, some medications taken by the patients (e.g. diuretics and short-acting nitrates) might affect plasma eotaxin levels. In conclusion, our results show that there is no clear association between the presence of eotaxin 67G>A SNP, its plasma levels and CAD parameters in post-MI patients and that circulating eotaxin levels do not differ between subjects with clinical manifestations of coronary atherosclerosis and healthy controls.

Pyrosequencing of the DNA gyrase gene in Neisseria species: effective indicator of ciprofloxacin resistance in Neisseria gonorrhoeae.

The quinolone resistance determining region (QRDR) of the gyrA gene in ciprofloxacin-susceptible strains (n=53) and strains of Neisseria spp. with reduced susceptibility (n=70) was determined by the pyrosequencing method. Results showed that the QRDR of the gyrA gene is an effective molecular indicator of resistance to ciprofloxacin in Neisseria gonorrhoeae, and presumably in Neisseria meningitidis, but not in all other Neisseria spp. This sequence was not unique for N. gonorrhoeae and seems unsuitable for species verification of N. gonorrhoeae. However, whether it is also possible to use this region for verification depends on the specificity of the primary screening method used.