The baroreceptor reflex as a predictor of crises in arterial hypertension]

The sensitivity of baroreceptor reflex was determined by the "neck chamber" method at a pressure of 40 mm Hg in patients with mild, moderate and malignant arterial hypertension (AH). A 24-hour blood monitoring was performed in patients with mild and moderate AH. There was a negative correlation between the lowering values in blood pressure on baroreceptor stimulation and the incidence of hypertensive crises in all the groups. There was also a negative correlation between the baroreceptor sensitivity and the daily blood pressure variations in patients with moderate AH. The findings suggest that a decrease in baroreceptor sensitivity might be a predictor of the critical course of AH.     

Phenotype related changes of intimal smooth muscle cells from human aorta in primary culture.

To study the functional characteristics of smooth muscle cell (SMC) phenotypes, we have investigated myosin expression, cell proliferation, collagen production and low-density lipoprotein (LDL) receptor activity in intimal SMCs of normal human aorta during their growth in primary culture. By staining with rabbit antibodies to smooth muscle myosin (ASMM) 3 cell types could be distinguished in culture: homogeneously stained cells, cells with discontinuous myosin fibrils and myosin-negative cells. The ratio of cell types greatly changed with culture growth: on days 5, 7 and 14 it was 82:1:17%, 70:5:25% and 10:30:60%, respectively. After 5-6 days of culture intimal SMCs began to proliferate and DNA-synthesizing nuclei were seen 1.5-4.3 times more frequently in myosin-negative cells than in cells with homogeneous myosin distribution. At that time the number of cells reacted with monoclonal antibody (MAb) to an epitope shared collagen types I and III started to increase. By double immunofluorescence staining it was shown that the cultured cells containing both ASMM and MAb markers were found 2.0-4.8 times more rarely than MAb-positive staining in myosin-negative cells. During the first 5 days in culture LDL binding and uptake were diminished in intimal cells with intercellular lipid inclusions independently of their myosin staining pattern, but their activity increased with culture growth. Thus, SMCs from human aortic intima change their phenotype on days 6 and 7 in primary culture as manifested by alteration of myosin expression, increased cell proliferation, collagen production and LDL receptor activity. Changes in myosin expression, however, are not an essential prerequisite for cell proliferation and collagen production.     

Formation of Gold Nanoparticle Self-Assembling Films in Various Polymer Matrices for SERS Substrates

Surface-enhanced Raman spectroscopy (SERS) is regarded as a versatile tool for studying the composition and structure of matter. This work has studied the preparation of a SERS substrate based on a self-assembling plasmonic nanoparticle film (SPF) in a polymer matrix. Several synthesis parameters for the SPF are investigated, including the size of the particles making up the film and the concentration and type of the self-assembling agent. The result of testing systems with different characteristics is discussed using a model substance (pseudoisocyanin iodide). These models can be useful in the study of biology and chemistry. Research results contain the optimal parameters for SPF synthesis, maximizing the SERS signal. The optimal procedure for SPF assembly is determined and used for the synthesis of composite SPFs within different polymer matrices. SPF in a polymer matrix is necessary for the routine use of the SERS substrate for various types of analytes, including solid samples or those sensitive to contamination. Polystyrene, polyvinyl alcohol (PVA), and polyethylene are investigated to obtain a polymer matrix for SPF, and various methods of incorporating SPF into a polymer matrix are being explored. It is found that films with the best signal enhancement and reproducibility were obtained in polystyrene. The minimum detectable concentration for the SERS substrate obtained is equal to 10⁻¹⁰ M. We prepared a SERS substrate with an analytical enhancement factor of 2.7 × 10⁴, allowing an increase in the detection sensitivity of analyte solutions of five orders of magnitude.     

Complex IgE sensitization patterns in ragweed allergic patients: Implications for diagnosis and specific immunotherapy

BackgroundRagweed (Ambrosia artemisiifolia) is one of the most important allergen sources, worldwide, causing severe respiratory allergic reactions in late summer and fall, in sensitized patients. Amb a 1 has been considered as the most important allergen in ragweed but 12 ragweed pollen allergens are known. The aim of our study was to investigate IgE reactivity profiles of ragweed allergic patients and to associate them with clinical symptoms.MethodsIgE sensitization profiles from clinically well‐characterized ragweed allergic patients (n = 150) were analyzed using immunoblotted ragweed pollen extract. Immunoblot inhibition experiments were performed with two Amb a 1 isoforms and CCD markers and basophil activation experiments were performed with IgE serum before and after depletion of Amb a 1‐specific IgE.ResultsBy IgE‐immunoblotting 19 different IgE reactivity patterns with and without Amb a 1‐sensitization were found. The majority of patients (>95%) suffered from rhino‐conjunctivitis, around 60% reported asthma‐like symptoms and about 25% had skin reactions. Patients with complex IgE sensitization profiles tended to have more clinical symptoms. Serum with and without Amb a 1‐specific IgE induced basophil activation.ConclusionsRagweed pollen allergic patients exhibit complex IgE reactivity profiles to ragweed allergens including Amb a 1 isoforms and cross‐reactive carbohydrates indicating the importance of Amb a 1 isoforms and additional allergens for diagnosis and allergen‐specific immunotherapy of ragweed allergy.