ABSTRACT
Based on the success of the Sabin2-based vaccine, a next-generation nOPV2 poliovirus vaccine has been developed. For epidemic monitoring and conducting epidemiological investigations, it is necessary to have a diagnostic assay with the ability to differentiate this variant from others. Here we describe such a real-time RT-PCR assay. The region with the cre insertion in the 5'-UTR was chosen as the target, and the limit of detection was 103 copies/mL (2.5×103 copies/mL using Probit analysis) determined using armored RNA particles. Sensitivity and specificity were 86.28 - 100â¯% and 76.84 - 100â¯%, respectively (with 95â¯% CI). Thus, this method can be effectively used when it is necessary to make a differential diagnosis of poliovirus strains.
ABSTRACT
Ixodes tick-borne borreliosis caused by Borrelia miyamotoi (ITBB-BM) is a previously unknown infectious disease discovered in Russia. AIM: The present study continues the investigation of the clinical features of ITBB-BM in the context of an immune system-pathogen interaction. SUBJECTS AND METHODS: The study enrolled 117 patients with ITBB-BM and a comparison group of 71 patients with Lyme disease (LD) that is ITBB with erythema migrans. All the patients were treated at the New Hospital, Yekateringburg. More than 100 clinical, epidemiological and laboratory parameters were obtained from each patient's medical history and included in the general database. A subset of patients hospitalized in 2015 and 2016 underwent additional laboratory examinations. Namely, the levels of B. miyamotoi-specific IgM and IgG antibodies were measured by the protein microarray containing GlpQ protein and four variable major proteins (VMPs): Vlp15/16, Vlp18, Vsp1, and Vlp5. The blood concentration of Borrelia was estimated by quantitative real-time PCR. RESULTS: In contrast to LD, first of all (p<0.001) the following clinical features were typical for ITBB-BM: the absence of erythema migrans (in 95% of patients), fever (93%), fatigue (96%), headache (82%), chill (41%), nausea (28%), lymphopenia (56%), thrombocytopenia (46%), the abnormal levels of alanine aminotransferase (54%) and C-reactive protein (98%), proteinuria (61%). Given the set of these indicators, the course of ITBB-BM was more severe in approximately 70% of patients. At admission, only 13% and 38% of patients had antibodies to GlpQ and VMPs, respectively; at discharge, antibodies to GlpQ and VMPs were detected in 88% of patients. There was no statistically significant association of the antibody response with individual clinical manifestations and laboratory parameters of the disease. However, patients with more severe ITBB-BM produced less IgM antibodies to VMPs and GlpQ at the time of discharge. CONCLUSION: ITBB-BM is a moderate systemic disease accompanied by the production of specific antibodies in virtually all patients.
Subject(s)
Antibodies, Bacterial/blood , Bacterial Proteins/immunology , Borrelia/pathogenicity , Ixodes/virology , Lyme Disease , Relapsing Fever , Adult , Animals , Humans , Lyme Disease/blood , Lyme Disease/physiopathology , Lyme Disease/virology , Phosphoric Diester Hydrolases/immunology , Relapsing Fever/blood , Relapsing Fever/physiopathology , Relapsing Fever/virologyABSTRACT
Nowadays enzymatic synthesis of genes is the most powerful tool for fast resolution of the various tasks in the field of basic and applied biological research. PCR-based gene assembly from overlapping oligonucleotides has become a widely used strategy. However, all the methods described in the literature are not perfect and need an extra processing step. In this study we are verifying Phusion high-fidelity polymerase as a tool to reduce nucleotide mismatches in de novo gene synthesis, thus facilitating subsequent cloning. To test the efficiency of the polymerase, we selected Fel d 4 gene, which is a 581 bp DNA sequence encoding the lipocalin allergen protein, one of the major cat allergens. The approach described here, therefore, would be useful in DNA sequences creation.
ABSTRACT
In early February 2014, an outbreak of the Ebola virus disease caused by Zaire ebolavirus (EBOV) occurred in Guinea; cases were also recorded in other West African countries with a combined population of approximately 25 million. A rapid, sensitive and inexpensive method for detecting EBOV is needed to effectively control such outbreak. Here, we report a real-time reverse-transcription PCR assay for Z. ebolavirus detection used by the Specialized Anti-epidemic Team of the Russian Federation during the Ebola virus disease prevention mission in the Republic of Guinea. The analytical sensitivity of the assay is 5 × 10(2) viral particles per ml, and high specificity is demonstrated using representative sampling of viral, bacterial and human nucleic acids. This assay can be applied successfully for detecting the West African strains of Z. ebolavirus as well as on strains isolated in the Democratic Republic of the Congo in 2014.
Subject(s)
Ebolavirus/isolation & purification , Hemorrhagic Fever, Ebola/diagnosis , Real-Time Polymerase Chain Reaction/methods , Reverse Transcriptase Polymerase Chain Reaction/methods , Africa, Western/epidemiology , Democratic Republic of the Congo , Disease Outbreaks/prevention & control , Ebolavirus/genetics , Guinea/epidemiology , Hemorrhagic Fever, Ebola/epidemiology , Humans , RNA, Viral/genetics , Russia , Sensitivity and SpecificityABSTRACT
In this study, we investigated the possibility of increasing the level of transgene expression using DNA element that can terminate transcription.