Anda Kadiša, Zaiga Nora-Krūkle, Simons Švirskis, Pēteris Studers, Irute Girkontaite, Aivars Lejnieks and Modra Murovska
Rheumatoid arthritis (RA) is a chronic autoimmune disease that causes erosive changes and ankylosis of joints and may cause internal injuries. Osteoarthritis (OA) is a degenerative process of the articular cartilage. However, inflammatory mediators may play a pivotal role in the initiation and perpetuation of the OA process. It is necessary to continue to study possible factors that may promote the development of the disease. The goal of this study was to evaluate the frequency and activity stage of parvovirus B19 (B19V) and persistent human herpes virus (HHV)-6 and HHV-7 infection in RA and OA patients, and healthy persons, in relation to cytokine levels and presence or absence of viral infections. RA patients with active B19V infection had the highest levels of tumour necrosis factor alpha (TNF-α), which may contribute to the development of RA. In the case of OA, the TNF-α level was higher in patients with active persistent B19V infection, suggesting that B19V reactivation affects also OA. Interleukin (IL)-6, IL-10 and metalloproteinase (MMP)-9 levels were higher in RA patients with latent HHV-6/-7 infection in comparison with active HHV-6/-7 infection, whereas in OA patients levels of all studied cytokines were very variable, ranging from low to high but without significant differences. This suggests that also latent HHV-6 and -7 viral infections can promote development of RA.
Vitalij Novickij, Irutė Girkontaitė, Audrius Grainys, Auksė Zinkevičienė, Eglė Lastauskienė, Jurgita Švedienė, Algimantas Paškevičius, Svetlana Markovskaja and Jurij Novickij
Electroporation is an electric field induced phenomenon occurring when the permeability of the cell membrane is increased due to the excess of critical transmembrane potential. Fluorescent dye assays are frequently used for evaluation of the permeabilization rate, however, the protocols vary, which negatively affects the repeatability of the results. In this work we have designed experiments to investigate the protocols and threshold concentrations of the Propidium Iodide (PI) and YO-PRO-1 (YP) fluorescent dyes for evaluation of mammalian cell permeabilization induced by electroporation. The Sp2/0 mouse myeloma cells were used and the bursts of 100 μs × 8 electrical pulses of 0.8-2 kV/cm were applied. It has been shown that the dye concentration has an influence on the detectable permeabilization, and the concentrations below 30 μM for PI and 1 μM for YP should be avoided for measurement of electropermeabilization efficacy due to unreliable fluorescence signals. Further, based on the experimental data, the permeabilization curve for the Sp2/0 myeloma cells in the 0.8-2 kV/cm range has been presented.
Zaiga Nora-Krūkle, Santa Rasa, Anda Vilmane, Sabīne Grāvelsiņa, Mārtiņš Kālis, Inga Ziemele, Milda Naciute, Sigita Petraitiene, Diana Mieliauskaite, Migle Klimantaviciene, Irute Girkontaite, Hsin-Fu Liu, Jih-Hui Lin, Yung-Cheng Lin, Hsiu-Chuan Chan, Dace Gardovska and Modra Murovska
Human bocavirus 1 (HBoV1) is a parvovirus recently found to be a possible aetiologic agent of acute respiratory disease in children. We conducted the first clinical and molecular study on this virus in Latvia (LV) and Lithuania (LT). The aim of the study was to determine the occurrence of HBoV1 in respiratory tract samples taken from hospitalised children with acute respiratory tract infections in LV and LT. In total 186 children with age one to 50 months, and who fulfilled criteria of acute respiratory tract infection, including lower respiratory tract infections, with or without fever, were included in this study. A nasopharyngeal aspirate was obtained from each patient on admission. DNA was isolated and polimerase chain reaction (PCR) performed targeting the HBoV1 NS1sequence. HBoV1 positive samples were sequenced and phylogenetic analysis was performed. HBoV1 sequence was detected in 42 (32%) of 130 LV and in 8 (14%) of 56 LT samples. In LV the majority of patients with HBoV1 infection were observed in February while in LT in October. The phylogenetic tree for HBoV1 indicated that isolates of HBoV1 cluster closely and include almost all of the isolates in this study. HBoV1 is common in Latvia and Lithuania and might be a significant pathogen that contributes to acute respiratory tract infections in children.