Type I hypersensitivity is mediated by the production of IgE antibodies in response to normally harmless substances. Debate still continues about the mechanisms underlying allergic reactions. Reduced barrier tissue function can be one of the risk factors for allergies. The aim of the present work was to compare the humoral immune response to Epstein-Barr virus in patients allergic to the A. alternata fungus or D. farinae house dust mites and healthy donors. It is known that up to 90% of the world population are infected with EBV. This infection occurs at early age when a child develops allergy. The antibodies were analyzed using immuno-PCR and the recombinant EBV protein rEBNA. We were able to demonstrate that infection occurs at early age in both allergic patients and healthy donors. The proportion of EBP-seropositive individuals was comparable between the groups (75% and 74%). The proportion of patients with high IgG1 titers among patients with allergies was lower (7%) than in healthy donors (18%), suggesting a lower viral load. In patients with allergies (but not in healthy donors) IgG1 titers declined as children grew older (р = 0.037). Besides, IgA1 titers were increased in patients with allergies in comparison with healthy donors, but differed between patients allergic to A. alternata and house dust mites. In allergic individuals, production of IgM against EBV was triggered earlier than in healthy donors. We conclude that IgM production and the IgA1-mediated humoral response occur earlier in patients with allergies, causing a decline in IgG1 titers over time.
VIEWS 4340
Injuries to the heart are uncommon in peacetime, yet they result in life-threatening conditions, which makes timely diagnostics a crucial factor in saving patients' lives. In this connection, it is important to define the main signs of heart injuries. This study aimed to analyze the basic clinical symptoms associated with various wounds to the heart. We have retrospectively analyzed such symptoms registered in 86 patients with varying chest injuries that affect the heart. All patients were treated in the emergency surgery unit of the Engels Town Hospital from 1991 to 2017. 41 (47.6%) patient had stab wounds, and there were 45 (52.3%) cases of gunshot wounds. 23 (26.7%) patients had chest injuries affecting heart exclusively, while for 63 (73.2%) the consequences were wounds to other organs. We found that the clinical picture depends on the kind of injury to the heart: stab and slash wounds translate into more pronounced symptoms, while gunshot wounds do not produce such an effect. Accepting patients, practitioners should take this fact into account. The misdiagnosis rate for stab and slash heart wounds is 9.7%, that for gunshot wounds — 17.7%, the latter being the result of vagueness of the clinical picture. The clinical signs are most pronounced in the cases of stab and slash wounds to the heart.
VIEWS 4120
Selection of antibodies using phage display involves the preliminary cloning of the repertoire of sequences encoding antigen-binding domains into phagemid, which is considered the bottleneck of the method, limiting the resulting diversity of libraries and leading to the loss of poorly represented variants before the start of the selection procedure. Selection in cell-free conditions using a ribosomal display is devoid from this drawback, however is highly sensitive to PCR artifacts and the RNase contamination. The aim of the study was to test the efficiency of a combination of both methods, including pre-selection in a cell-free system to enrich the source library, followed by cloning and final selection using phage display. This approach may eliminate the shortcomings of each method and increase the efficiency of selection. For selection, alpaca VHH antibody sequences suitable for building an immune library were used due to the lack of VL domains. Analysis of immune libraries from the genes of the VH3, VHH3 and VH4 families showed that the VHH antibodies share in the VH3 and VH4 gene groups is insignificant, and selection from the combined library is less effective than from the VHH3 family of sequences. We found that the combination of ribosomal and phage displays leads to a higher enrichment of high-affinity fragments and avoids the loss of the original diversity during cloning. The combined method allowed us to obtain a greater number of different high-affinity sequences, and all the tested VHH fragments were able to specifically recognize the target, including the total protein extracts of cell cultures.
VIEWS 4406
The diagnosis and treatment of patients with angiographically normal or near normal coronary arteries remains a clinically relevant problem. The aim of this study was to assess diastolic function in patients with chest pain and normal/near normal coronary arteries (NECA) using ECG-gated SPECT/CT. The study recruited 49 patients presenting with chest pain, a positive cardiac stress test and normal coronary arteries, as demonstrated by coronary angiography. All patients were ordered a myocardial SPECT/CT scan, which was performed according to a two-day protocol. After the scan, the patients were divided into 3 groups. Group 1 consisted of 17 patients with microvascular angina. Group 2 was composed of 22 patients with borderline-high blood pressure or stage I hypertensive heart disease associated with secondary microvascular dysfunction. Ten seemingly healthy individuals constituted the control group. According to coronary angiography, the controls had no cardiovascular pathologies accompanied by coronary artery disorders or impaired myocardial perfusion (SPECT). The majority of patients from groups 1 and 2 were found to have impaired diastolic function. The impairments were more pronounced in group 2 tended to exacerbate with stress. The most sensitive parameter of diastolic function, MFR/3, was outside the reference range in almost all patients in groups 1 and 2. MFR/3 characterizes the mean filling rate of the left ventricle in the first third of diastole. The control group showed no symptoms of diastolic dysfunction. Thus, the patients with chest pain, a positive stress test and NECA had signs of left ventricular diastolic dysfunction exacerbated with stress. Such patients are at risk for heart failure with preserved ejection fraction.
VIEWS 3977