scholarly journals Molecular Detection of Borrelia Bacteria in Cerebrospinal Fluid-Optimisation of Pre-Analytical Sample Handling for Increased Analytical Sensitivity

Diagnostics ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2088
Author(s):  
Malin Lager ◽  
Peter Wilhelmsson ◽  
Andreas Matussek ◽  
Per-Eric Lindgren ◽  
Anna J. Henningsson
Keyword(s):  
Cerebrospinal Fluid ◽  
16S Rrna ◽  
Clinical Diagnostics ◽  
Systematic Evaluation ◽  
Clinical Samples ◽  
Rrna Gene ◽  
Analytical Sensitivity ◽  
Gene 16S Rrna ◽  
Pcr Targeting ◽  
The 16S Rrna Gene

The main tools for clinical diagnostics of Lyme neuroborreliosis (LNB) are based on serology, i.e., detection of antibodies in cerebrospinal fluid (CSF). In some cases, PCR may be used as a supplement, e.g., on CSF from patients with early LNB. Standardisation of the molecular methods and systematic evaluation of the pre-analytical handling is lacking. To increase the analytical sensitivity for detection of Borrelia bacteria in CSF by PCR targeting the 16S rRNA gene, parameters were systematically evaluated on CSF samples spiked with a known amount of cultured Borrelia bacteria. The results showed that the parameters such as centrifugation time and speed, the use of complementary DNA as a template (in combination with primers and a probe aiming at target gene 16S rRNA), and the absence of inhibitors (e.g., erythrocytes) had the highest impact on the analytical sensitivity. Based on these results, a protocol for optimised handling of CSF samples before molecular analysis was proposed. However, no clinical evaluation of the proposed protocol has been done so far, and further investigations of the diagnostic sensitivity need to be performed on well-characterised clinical samples from patients with LNB.

scholarly journals Analytical Sensitivity, Reproducibility of Results, and Clinical Performance of Five PCR Assays for Detecting Chlamydia pneumoniae DNA in Peripheral Blood Mononuclear Cells

2000 ◽  
Vol 38 (7) ◽  
pp. 2622-2627 ◽  
Author(s):  
J. B. Mahony ◽  
S. Chong ◽  
B. K. Coombes ◽  
M. Smieja ◽  
A. Petrich
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Nested Pcr ◽  
Chlamydia Pneumoniae ◽  
Mononuclear Cells ◽  
Rrna Gene ◽  
Analytical Sensitivity ◽  
Infected Cells ◽  
Pcr Assays ◽  
The 16S Rrna Gene

Chlamydia pneumoniae has been associated with atherosclerosis and coronary artery disease (CAD), and its DNA has been detected in atheromatous lesions of the aorta, carotid, and coronary arteries by a variety of PCR assays. The objective of this study was to compare the performances of five published PCR assays in the detection of C. pneumoniae in peripheral blood mononuclear cells (PBMCs) from patients with coronary artery disease. The assays included two conventional PCRs, one targeting a cloned PstI fragment and one targeting the 16S rRNA gene; two nested PCRs, one targeting the 16S rRNA gene and one targeting ompA; and a touchdown enzyme time release (TETR) PCR, targeting the 16S rRNA gene. All PCRs had similar analytical sensitivities and detected a minimum of 0.005 inclusion-forming units (IFU) of C. pneumoniae; the ompA nested PCR and the TETR PCR were slightly more sensitive and detected 0.001 IFU. Assay reproducibility was examined by testing 10 replicates of C. pneumoniae DNA by each assay. All five assays showed excellent reproducibility at high levels of DNA, with scores of 10 out of 10 for 0.01 IFU, but exhibited decreased reproducibility for smaller numbers of C. pneumoniae IFU for all tests. Pairwise comparison of test results indicated that there was a significant difference between tests (Cochran Q = 32.0, P < 0.001), with thePstI fragment (P < 0.001) and 16S rRNA (P = 0.002) assays having lower reproducibility than the nested ompA and TETR assays. To further analyze assay sensitivity, C. pneumoniae-infected U-937 mononuclear cells were added to whole blood, and extracted mononuclear-cell DNA was tested by each assay. All five assays showed similar sensitivities, detecting 15 infected cells; three assays detected 3 infected cells, while all assays were negative at the next dilution (1.5 infected cells). A striking difference in performance of the five assays was seen, however, when PBMCs from CAD patients were tested for C. pneumoniae DNA. The ompA nested PCR detected C. pneumoniae DNA in 11 of 148 (7.4%) specimens, the 16S rRNA nested PCR detected 2 positives among the 148 specimens (1.4%) (P < 0.001), and the other 3 assays detected no positive specimens (P < 0.001, compared with theompA assay). These results indicate that analytical sensitivity alone does not predict the ability of an assay to detectC. pneumoniae in whole-blood-derived PBMCs. Before standardized assays can be used in wide-scale epidemiological studies, further characterization of these assays will be required to improve our understanding of their performance in the detection of C. pneumoniae in clinical material.

scholarly journals Ochrobactrum pseudintermedium sp. nov., a novel member of the family Brucellaceae, isolated from human clinical samples

2007 ◽  
Vol 57 (5) ◽  
pp. 1007-1013 ◽  
Author(s):  
Corinne Teyssier ◽  
Hélène Marchandin ◽  
Hélène Jean-Pierre ◽  
Agnès Masnou ◽  
Ghislaine Dusart ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Gene Sequence ◽  
Sequence Similarity ◽  
Clinical Samples ◽  
Rrna Gene ◽  
The Family ◽  
Ochrobactrum Intermedium ◽  
Physiological And Biochemical ◽  
The 16S Rrna Gene

Three novel Gram-negative, non-fermenting aerobic bacilli were isolated from human clinical samples. They shared more than 99.8 % of the 16S rRNA gene nucleotide positions. The strains were related to Ochrobactrum intermedium with about 97.48 % 16S rRNA gene sequence similarity. In 16S rRNA gene-, dnaK- and rpoB-based phylogenies, the strains were grouped in a lineage that was distinct from other Ochrobactrum species in the family Brucellaceae. Fatty acid composition, polar lipids, quinone system, DNA–DNA relatedness, genome organization, and physiological and biochemical data differentiated these isolates from recognized species of the genus Ochrobactrum. The three clinical strains therefore represent a novel species within the genus Ochrobactrum, for which the name Ochrobactrum pseudintermedium sp. nov., is proposed. The type strain is ADV31T (=CIP 109116T=DSM 17490T). The DNA G+C content of strain ADV31T was 54.5 mol%.

scholarly journals Negativicoccus succinicivorans gen. nov., sp. nov., isolated from human clinical samples, emended description of the family Veillonellaceae and description of Negativicutes classis nov., Selenomonadales ord. nov. and Acidaminococcaceae fam. nov. in the bacterial phylum Firmicutes

2010 ◽  
Vol 60 (6) ◽  
pp. 1271-1279 ◽  
Author(s):  
Hélène Marchandin ◽  
Corinne Teyssier ◽  
Josiane Campos ◽  
Hélène Jean-Pierre ◽  
Frédéric Roger ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Clinical Samples ◽  
Rrna Gene ◽  
The Novel ◽  
Gene Sequences ◽  
16S Rrna Gene Sequences ◽  
Gram Negative ◽  
The Family ◽  
The 16S Rrna Gene

Three strains of a hitherto unknown, Gram-negative, tiny, anaerobic coccus were collected from human clinical samples originating from skin and soft tissues. The three isolates displayed at least 99.9 % identity in their 16S rRNA gene sequences and more than 99.8 % identity in their dnaK gene sequences. The isolates were affiliated to the family Veillonellaceae, the coccobacillus Dialister micraerophilus being the most closely related species, but there was no more than 91.1 % identity in the 16S rRNA gene sequence between this species and the three isolates. Phylogeny based on the 16S rRNA gene confirmed that the three strains represent a novel and robust lineage within the current family Veillonellaceae. A similar genomic structure was demonstrated for the three isolates by PFGE-based analysis. Morphology and metabolic end products, as well as genotypic and phylogenetic data supported the proposal of the novel genus Negativicoccus gen. nov., with the novel species Negativicoccus succinicivorans sp. nov. [type strain ADV 07/08/06-B-1388T (=AIP 149.07T=CIP 109806T=DSM 21255T=CCUG 56017T) as type species]. Phylogenetic analyses based on the 16S rRNA gene sequences of members of the phylum Firmicutes and other phyla indicated that the family Veillonellaceae forms a robust lineage clearly separated from those of the classes ‘Bacilli’, ‘Clostridia’, Thermolithobacteria and ‘Erysipelotrichi’ in the phylum Firmicutes. Therefore, we propose that this family is a class-level taxon in the phylum Firmicutes, for which the name Negativicutes classis nov. is proposed, based on the Gram-negative type of cell wall of its members, with the type order Selenomonadales ord. nov. In this order, a novel family, Acidaminococcaceae fam. nov., is proposed and description of the family Veillonellaceae is emended.

Assessment of real-time PCR for diagnosis ofMycoplasma pneumoniaepneumonia in pediatric patients

2006 ◽  
Vol 52 (2) ◽  
pp. 125-129 ◽  
Author(s):  
Miyuki Morozumi ◽  
Akira Ito ◽  
Somay Y Murayama ◽  
Keiko Hasegawa ◽  
Reiko Kobayashi ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Real Time ◽  
Mycoplasma Pneumoniae ◽  
Real Time Pcr ◽  
High Sensitivity ◽  
Community Acquired Pneumonia ◽  
Clinical Samples ◽  
Rrna Gene ◽  
The 16S Rrna Gene

We developed a real-time PCR to detect Mycoplasma pneumoniae with a primer set designed for the 16S rRNA gene. Clinical samples (n = 937) were collected from children with community-acquired pneumonia between April 2002 and March 2004 at 12 Japanese medical institutions. Sensitivity of real-time PCR was calculated as 10 colony-forming units per reaction tube using a pMP01 plasmid carrying a 225-bp target DNA fragment of the 16S rRNA gene in M. pneumoniae M129, a standard strain. Results, obtained within 2 h, were compared with those of conventional culture and serologic methods. Of all cases tested, 151 (16.4%) and 129 (13.8%) were positive for M. pneumoniae by real-time PCR and by culture, respectively. Among the 151 cases, almost all of those tested serologically by passive agglutination showed a rise in M. pneumoniae antibody titre between acute and convalescent sera. We conclude that this real-time PCR can identify M. pneumoniae rapidly and fulfills the need for rapid identification, high sensitivity, and high specificity.Key words: real-time PCR, Mycoplasma pneumoniae identification, pediatrics, community-acquired pneumonia, Mycoplasma pneumoniae culture.

scholarly journals Accuracy of Conventional PCR Targeting the 16S rRNA Gene with the Ot-16sRF1 and Ot-16sRR1 Primers for Diagnosis of Scrub Typhus: a Case-Control Study: TABLE 1

2015 ◽  
Vol 54 (1) ◽  
pp. 178-179 ◽  
Author(s):  
Choon-Mee Kim ◽  
Min Keun Cho ◽  
Dong-Min Kim ◽  
Na-Ra Yun ◽  
Seok Won Kim ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Scrub Typhus ◽  
Rrna Gene ◽  
Conventional Pcr ◽  
Content Type ◽  
Increased Sensitivity ◽  
Good Diagnostic Accuracy ◽  
Pcr Targeting ◽  
The 16S Rrna Gene

We retrospectively evaluated the accuracy of conventional PCR targeting the 16S rRNA gene (16S C-PCR) using the Ot-16sRF1/Ot-16sRR1 primers for diagnosing scrub typhus. The diagnosis ofOrientia tsutsugamushiinfection by 16S C-PCR presented an increased sensitivity of 87.0% and specificity of 100% compared with those obtained with other targets and is thus a simple and clinically useful method with good diagnostic accuracy.

scholarly journals Genes Encoding Toxin ofClostridium difficilein Children with and without Diarrhea

Scientifica ◽  
2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
Victor R. C. Merino ◽  
Viviane Nakano ◽  
Sydney M. Finegold ◽  
Mario J. Avila-Campos
Keyword(s):  
16S Rrna ◽  
Binary Toxin ◽  
Genetic Profile ◽  
Rrna Gene ◽  
Toxin B ◽  
Genes Encoding ◽  
Gene 16S Rrna ◽  
Stool Samples ◽  
Toxigenic Strains ◽  
The 16S Rrna Gene

The presence of gene 16S rRNA and genes encoding toxin A (tcdA), toxin B (tcdB), and binary toxin (cdtA/cdtB) ofClostridium difficilein stool samples from children with (110) and without (150) diarrhea was determined by using a TaqMan system. Fifty-seven (21.9%) out of 260 stool samples harbored the 16S rRNA gene. The genetic profile oftcdA+/tcdB−andcdtA+/cdtB+was verified in oneC. difficile-positive diarrhea sample and oftcdA+/tcdB+in threeC. difficile-positive nondiarrhea samples. The presence oftcdA+/tcdB+in stools obtained from children without diarrhea, suggests that they were asymptomatic carriers of toxigenic strains.

scholarly journals Comparison of P1 and 16S rRNA genes for detection of Mycoplasma pneumoniae by nested PCR in adults in Zhejiang, China

2015 ◽  
Vol 9 (03) ◽  
pp. 244-253 ◽  
Author(s):  
Zibo Zhou ◽  
Xiangzhi Li ◽  
Xiaojian Chen ◽  
Lili Yao ◽  
Changwang Pan ◽  
...  
Keyword(s):  
16S Rrna ◽  
16S Rrna Gene ◽  
Mycoplasma Pneumoniae ◽  
Nested Pcr ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Clinical Samples ◽  
Rrna Gene ◽  
Positive Rate ◽  
The 16S Rrna Gene

Introduction: Mycoplasma pneumoniae (M. pneumoniae) is the most common atypical pathogen that causes respiratory infections in humans. Laboratory tests are important in the diagnosis of M. pneumoniae because of the atypical features in clinical signs and symptoms. Nowadays, both the P1 adhesin gene and 16S ribosomal (r) RNA (rRNA) gene of M. pneumoniae have been widely detected by polymerase chain reaction (PCR). The purpose of the present study was to evaluate the most suitable target in the detection of M. pneumonia via nested PCR. Methodology: Both the P1 adhesin gene and 16S rRNA gene for nested PCR reaction conditions were optimized through an orthogonal test and single-factor experiment. Then, the sensitivity of the two sets of targets was evaluated. Finally, based on the optimal conditions, 55 clinical samples of throat swabs collected from adult patients in 2013 were examined by established nested PCR. Result: The results revealed that PCR detection of the 16S rRNA gene was more sensitive than the P1 adhesin gene because the detection limits for both the P1 gene and 16S rRNA gene were at least 100 fg and 10 fg of M. pneumoniae DNA, respectively. Furthermore, the positive rate for detection of the 16S rRNA gene (30/55; 54.5%) was higher than that of the P1 adhesin gene (25/55; 45.5%). Conclusion: Our results indicate that the 16S rRNA gene is more suitable for diagnosis of M. pneumoniae infection than the P1 adhesin gene due to its higher sensitivity and positive rate in clinical samples.

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