Search

Protonated ions of fucose-containing oligosaccharides are prone to undergo internal glycan rearrangement which results in chimeric fragments that obfuscate mass-spectrometric analysis. Lack of accessible tools that would facilitate systematic analysis of glycans in the gas phase limits our understanding of this phenomenon. In this work, we use density functional theory modeling to interpret cryogenic IR spectra of Lewis a and blood group type H1 trisaccharides and to establish whether these trisaccharides undergo the rearrangement during gas-phase analysis. Structurally unconstrained search reveals that none of the parent ions constitute a thermodynamic global minimum. In contrast, predicted collision cross sections and anharmonic IR spectra provide a good match to available experimental data which allowed us to conclude that fucose migration does not occur in these antigens. By comparing the predicted structures with those obtained for Lewis x and blood group type H2 epitopes, we demonstrate that the availability of the mobile proton and a large difference in the relative stability of the parent ions and rearrangement products constitute the prerequisites for the rearrangement reaction. [ABSTRACT FROM AUTHOR]

Human pegivirus (HPgV) is transmitted through sexual or parenteral exposure and is common among patients receiving blood products. HPgV is associated with lower levels of human immunodeficiency virus (HIV) RNA and better survival among HIV-infected patients. This study aimed to investigate the prevalence of HPgV and determine its subtypes in HIV-infected individuals living in Istanbul, which has the highest rate of HIV infection in Türkiye. Total RNA extraction from plasma, cDNA synthesis, and nested PCR were performed for HPgV on plasma samples taken from 351 HIV-1-infected patients. The HPgV viral load was quantified on HPgV-positive samples. HPgV genotyping was performed by sequencing the corresponding amplicons. In the present study, the overall prevalence of HPgV RNA in HIV-infected patients was 27.3%. HPgV subtypes 1, 2a, and 2b were found, with subtype 2a being the most frequent (91.6%). Statistical analysis of HIV-1 viral load on HPgV viral load showed an opposing correlation between HIV-1 and HPgV loads. In conclusion, these data show that HPgV infection is common among HIV-positive individuals in Istanbul, Türkiye. Further comprehensive studies are needed to clarify both the cellular and molecular pathways of these two infections and to provide more information on the effect of HPgV on the course of the disease in HIV-infected individuals. [ABSTRACT FROM AUTHOR]

Human papilloma virus (HPV) is the most common sexually transmitted viral agent in the world and the most common cause of cervical cancer. HPV prevalence and genotype distribution vary by region and demographic data. In a province in the south of Turkey that constantly receives immigration, we aimed to determine the prevalence of high-risk HPV (HR-HPV) genotypes, evaluate the compatibility between cervical Pap smear cytology results patients and HR-HPVs, and make an up-to-date contribution to the elucidation of epidemiological data. In this single-centre study, a total of 12,641 women aged 18 and over were evaluated retrospectively from January 2019 to July 2022. HPV detection and genotyping were analysed by the PCR method. Bethesda scoring was used for Pap smear cytological evaluation. The overall prevalence of HR-HPV was 12.6% (12.7% in Turkish women, 11.2% in foreign women). Among the typed HPVs that were detected, HPV-16 (31%) was found first, followed by HPV-18 (8%). The prevalence of HR-HPV was higher in women with abnormal cytology (977/1762, 55.4%) than in women with normal cytology (620/10879, 5.7%) (p<0.001). Turkey doesn't yet have a national HPV immunisation program. We think that determining the specific regional frequency of other HR-HPVs separately will be useful in the follow-up of the natural course of the type-specific infection and in vaccine studies in the future.