TR Dizin İndeksli Yayınlar Koleksiyonu / TR Dizin Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/20.500.14365/4

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  • Article
    Analysis of Nucleotide Changes in Rt-Pcr Primer/Probe Binding Regions in Sars-Cov-2 Isolates Reported from Turkey
    (Ankara Microbiology Society, 2021-07-16) Sayıner, Ayça Arzu; Appak, Özgür; Demir, Ayse Banu; Bulgurcu, Alihan
    The SARS-CoV-2 virus, which caused the COVID-19 epidemic, caused more than 55 million cases and nearly 1.5 million deaths worldwide. For the microbiological diagnosis of the disease, the most valid method is detecting the presence of the viral genome by real-time reverse transcription polymerase chain reaction (rRT-PCR). However, due to the nature of the RNA viruses, frequent mutations may affect the sensitivity of the analyses made on the genetic material of the virus, such as PCR. In this study, we aimed to investigate the mutations in the primer-probe binding regions of the rRT-PCR panels used in COVID-19 diagnosis. SARS-CoV-2 whole genome sequence data (n= 194) isolated from COVID-19 cases in Turkey and uploaded on GISAID database from the centers in Istanbul (n= 78), Ankara (n= 58), Kars (n= 47), Bursa (n= 2), Adiyaman (n= 2), Erciyes (n= 1) and Kocaeli (n= 1) between March 17-September 14, 2020 were analyzed. In order to determine the nucleotide changes, SARS-CoV-2 sequences from Turkey were compared to the reference genome sequence (NC_045512.1) present in GenBank website. The constructed data set was aligned using the MAFFT program and was checked manually if the sequences were in the same frame by using the AliView program. Primer-probe binding sites of the thirteen SARS-CoV-2 rRT-PCR panels from seven different institutes (US CDC, China CDC, Charite CDC, Pasteur, HKU, Thailand, NIID) that are being used in COVID-19 diagnosis were evaluated in terms of nucleotide changes within the corresponding regions compared to the reference genome. Sequence diversities in the viral genomes were determined via positional nucleotide numerical calculator and entropy calculator modules and nucleotide and entropy changes in primer-probe binding regions for each rRT-PCR panel were examined. Among thirteen different primer-probe panels, nucleotide changes in the target regions of the seven primer-probe panels were determined. When viral sequences with nucleotide changes in the primer-probe binding regions were examined, the most common changes were observed in the China CDC N-forward primer and US CDC N3-forward primer binding regions. It is important that the kits to be used as diagnostic tests are designed specific to the regions with less nucleotide changes. Nucleotide changes may not be critical for DNA amplification for most PCR panels, but should be carefully monitored as they may affect the sensitivity of the assay. If the risk of alteration of the designed region is high, the primer - probe binding sites should be checked frequently and updated when necessary.
  • Article
    Citation - WoS: 2
    Citation - Scopus: 2
    Analysis of Nucleotide Changes in Rt-Pcr Primer/Probe Binding Regions in Sars-Cov Isolates Reported From Turkey
    (Ankara Microbiology Soc, 2021-07-16) Demir, Ayse Banu; Bulgurcu, Alihan; Appak, Ozgur; Sayiner, Ayca Arzu
    The SARS-CoV-2 virus, which caused the COVID-19 epidemic, caused more than 55 million cases and nearly 1.5 million deaths worldwide. For the microbiological diagnosis of the disease, the most valid method is detecting the presence of the viral genome by real-time reverse transcription polymerase chain reaction (rRT-PCR). However, due to the nature of the RNA viruses, frequent mutations may affect the sensitivity of the analyses made on the genetic material of the virus, such as PCR. In this study, we aimed to investigate the mutations in the primer-probe binding regions of the rRT-PCR panels used in COVID-19 diagnosis. SARS-CoV-2 whole genome sequence data (n= 194) isolated from COVID-19 cases in Turkey and uploaded on GISAID database from the centers in Istanbul (n= 78), Ankara (n= 58), Kars (n= 47), Bursa (n= 2), Adiyaman (n= 2), Erciyes (n= 1) and Kocaeli (n= 1) between March 17-September 14, 2020 were analyzed. In order to determine the nucleotide changes, SARS-CoV-2 sequences from Turkey were compared to the reference genome sequence (NC_045512.1) present in GenBank website. The constructed data set was aligned using the MAFFT program and was checked manually if the sequences were in the same frame by using the AliView program. Primer-probe binding sites of the thirteen SARS-CoV-2 rRT-PCR panels from seven different institutes (US CDC, China CDC, Charite CDC, Pasteur, HKU, Thailand, NIID) that are being used in COVID-19 diagnosis were evaluated in terms of nucleotide changes within the corresponding regions compared to the reference genome. Sequence diversities in the viral genomes were determined via positional nucleotide numerical calculator and entropy calculator modules and nucleotide and entropy changes in primer-probe binding regions for each rRT-PCR panel were examined. Among thirteen different primer-probe panels, nucleotide changes in the target regions of the seven primer-probe panels were determined. When viral sequences with nucleotide changes in the primer-probe binding regions were examined, the most common changes were observed in the China CDC N-forward primer and US CDC N3-forward primer binding regions. It is important that the kits to be used as diagnostic tests are designed specific to the regions with less nucleotide changes. Nucleotide changes may not be critical for DNA amplification for most PCR panels, but should be carefully monitored as they may affect the sensitivity of the assay. If the risk of alteration of the designed region is high, the primer - probe binding sites should be checked frequently and updated when necessary.
  • Article
    Citation - WoS: 32
    Citation - Scopus: 32
    Covid-19 Anxiety in People Living With Hiv: an Online Cross-Sectional Study
    (Tubitak Scientific & Technical Research Council Turkey, 2020-12-17) Kuman Tuncel, Ozlem; Pullukcu, Husnu; Erdem, Huseyin Aytac; Kurtaran, Behice; Tasbakan, Selin Ece; Isikgoz Tasbakan, Meltem; Tuncel, Ozlem Kuman
    Background/aim: The emergence of the coronavirus disease 2019 (COVID-19) outbreak has had an enormous emotional impact on sonic vulnerable groups, such as people living with human immunodeficiency virus (HIV) (PLHIV). This study was planned with the aim of assessing the anxiety levels of PLHIV and the sources of their anxiety. Materials and methods: A web-based questionnaire was sent to PLHIV using the virtual snowball sampling method. The questionnaire included questions about sociodemographic status, information about HIV infection, and the Beck Anxiety Inventory (BAI). Additionally, some opinions of the participants about COVID-19 were asked. Results: A total of 307 respondents, with a median age of 33 years, from 32 different cities, participated in the study. More than half of the respondents reported the belief that COVID-19 was not sufficiently well-known by the medical community and nearly 45% believed that they would have snore complications if they contracted COVID-19. One-fourth of the participants had anxiety. Having a preexisting psychiatric disorder, perceiving that they were practicing insufficient preventive measures, not being sure about the presence of any individuals with COVID-19 in their environment, and living with a household member with a chronic disease were found to be the risk factors of PLHIV for having anxiety during this pandemic. The BAI scores were correlated with the patient-reported anxiety levels about the spread of COVID-19 in Turkey, acquiring COVID-19, transmitting COVID-19 to another person, and transmitting HIV to another person. Among the stated conditions, the most common concern was the spread of COVID-19 all over the country, while the least common was transmitting HIV to someone else. Conclusion: The results revealed that a significant proportion of the sample had anxiety, and the findings were essential for developing evidence-based strategies for decreasing the anxiety of PLHIV, especially for those who had risk factors and to provide them with better health care during this pandemic or other pandemic-like crises.
  • Article
    Citation - WoS: 15
    Citation - Scopus: 17
    Identification of the Nucleotide Substitutions in 62 Sars-Cov Sequences From Turkey
    (Tubitak Scientific & Technical Research Council Turkey, 2020-06-21) Demir, Ayse Banu; Benvenuto, Domenico; Abacioglu, Hakan; Angeletti, Silvia; Ciccozzi, Massimo
    A previously unknown coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been shown to cause coronavirus disease 2019 (COVID-19) pandemic. The first case of COVID-19 in Turkey has been declared in March 11th, 2020 and from there on, more than 150,000 people in the country have been diagnosed with the disease. In this study, 62 viral sequences from Turkey, which have been uploaded to GISAID database, were analyzed by means of their nucleotide substitutions in comparison to the reference SARS-CoV-2 genome from Wuhan. Our results indicate that the viral isolates from Turkey harbor some common mutations with the viral strains from Europe, Oceania, North America and Asia. When the mutations were evaluated, C3037T, C14408T and A23403G were found to be the most common nucleotide substitutions among the viral isolates in Turkey, which are mostly seen as linked mutations and are part of a haplotype observed high in Europe.