Stellate cells of aortic intima: I. Human and rabbit.

Stellate cells hitherto accounted exclusively in the innermost elastic-hyperplastic layer were already reported to inhabit human aortic intima. The present paper shows that most of these cells are situated just beneath the endothelium. Stellate cells also appear in the deendothelialization-induced myointimal thickening of rabbit aorta. In the myointimal thickening these cells were revealed in the direct proximity to the endothelium. A conclusion is available that the previously demonstrated polymorphism of human aortic intimal cells may be reproduced in a simple experimental model, which gives new possibilities for the study of the cellular polymorphism in the vessel wall.     

Variability in host plant resistance of Sorghum to Striga Hermonthica infestation in West Africa

Fourteen elite sorghum lines were evaluated for their resistance to Striga hermonthica at three locations in Nigeria and Mali. Results showed that many of the lines especially MALISOR 84-1, SAMSORG 41, 97-SB-F5DT-64 (Keninkédié) and the check SRN 39 remained resistant to Striga in all locations with low emerged Striga counts, while SAMSORG 14 had the highest Striga infestation in all locations. Considerable variation in reaction to Striga infestation was observed on Séguètana, 97-SB-F5DT-63 (Wasa), 97-SB-F5DT-65, CMDT 38, CMDT 39 and CMDT 45 which were susceptible to Striga at Samaru, Nigeria but were resistant to Striga at both locations in Mali. Based on low Striga resistance and high grain yield, lines MALISOR 84-1, SAMSORG 41, 97-SB-F5DT-64, 97-SB-F5DT-65, CMDT 39 and SAMSORT 14 have been nominated for wider evaluation across more West African countries.     

Peculiarities of the antioxidant activity of tissues of rheophilic zoobenthic species in accordance to the results of chemiluminescent analysis

Adaptations of living organisms to the environment are formed and manifested at different levels, from molecular to biocoenotic. Nowadays, the metabolic antioxidant system (AOS) is considered the key part of the process of adaptation; its activation is considered a general response of biota to the negative effect of the environment. The usage of AOS components as biomarkers of the stress condition in hydrobionts has good prospects; it is actively applied in the monitoring of aquatic ecosystems. Here, the kinetics of the free radical formation in various zoobenthic species from the Yenisei River (amphipods, oligochaetes, leeches, and chironomids) and in the amphipods from the Us River (a small mountain river, the Yenisei tributary) is analyzed. The parameters of kinetics of radical formation were registered in vitro in the homogenates of hydrobionts tissues under the initiation of the oxidative stress by the hydrogen peroxide using luminol-dependent chemoluminescence. In amphipods, unlike other invertebrates, the antioxidative activity is characterized by two chemiluminescent peaks. In addition, the kinetics of free radical elaboration has interspecific and agerelated variability in amphipods. In Gmelinoides fasciatus Stebb., the peak of the free radical elaboration and their total number significantly exceeded these parameters for Gammarus sp. and Eulimnogammarus viridis Dybowsky in a 60-min period. The increase of the production of free radicals in E. viridis and Gammarus sp. and its decrease in G. fasciatus were age-dependent. A significantly higher production of free radicals has been registered in G. fasciatus and E. viridis inhabiting the zone of elevated anthropogenic load in the Yenisei River.     

Human recombinant laminin-binding protein: isolation, purification, and crystallization

The mRNA of the precursor of laminin-binding protein (LBP) was isolated from a human embryo kidney cell line and cloned. The determined sequence of the LBP gene showed complete identity with the LBP genes isolated from human lung and large intestine cells. The human LBP was expressed by E. coli cells, and it was purified using Ni-NTA-Sepharose chromatography. The mobility of the homogeneous recombinant human laminin-binding protein on SDS-PAGE was 43 kD. A mixture of eight murine monoclonal antibodies, the MPLR Pool against LBP, reacted with the recombinant LBP in Western blot. The interaction of the antiidiotypical antibodies 10H10 and E6B provided evidence that the epitope binding to protein E of the tick-borne encephalitis (TBE) virus is also preserved on the human recombinant LBP. Enzyme immunoassay confirmed the ability of the recombinant LBP to interact with protein E of TBE virus. The biological activity of the recombinant LBP allowed us to perform X-ray analysis of the spatial arrangement of the LBP molecule using the recombinant protein. For this purpose, crystals of the human LBP were obtained by the standing drop version of the pore diffusion technique. The crystals appropriate for X-ray structural analysis were 0.3 x 0.1 x 0.05 mm in size. The X-ray diffraction field of the crystal extended to 2.5 A.     

Two common nonsynonymous paraoxonase 1 (<Emphasis Type="Italic">PON1</Emphasis>) gene polymorphisms and brain astrocytoma and meningioma

Background  

Human serum paraoxonase 1 (PON1) plays a major role in the metabolism of several organophosphorus compounds. The enzyme is encoded by the polymorphic gene PON1, located on chromosome 7q21.3. Aiming to identify genetic variations related to the risk of developing brain tumors, we investigated the putative association between common nonsynonymous PON1 polymorphisms and the risk of developing astrocytoma and meningioma.     

Forms of LonB protease from Archaeoglobus fulgidus devoid of the transmembrane domain: the contribution of the quaternary structure to the regulation of enzyme proteolytic activity

Deletion of the transmembrane domain (TM-domain) of Archaeoglobus flggidus LonB protease (AfLon) was shown to result in uncontrollable activation of the enzyme proteolytic site and in vivo autolysis yielding a stable and functionally inactive fragment consisting of both alpha-helical and proteolytic domains (alphaP). The deltaTM-AfLonTM-S590A enzyme form, obtained by site-directed mutagenesis of the catalytic Ser residue, is capable of recombination with the alphaP fragment. The mixed oligomers were shown to be proteolytically active, which indicates a crucial role of subunit interactions in the activation of the AfLon proteolytic site. The thermophilic nature of AfLon protease was found to be due to the special features of the enzyme activity regulation, the structure of ATPase domain, and the quaternary structure.     

Forms of LonB protease from Archaeoglobus fulgidus devoid of the transmembrane domain: The contribution of the quaternary structure to the regulation of enzyme proteolytic activity

Deletion of the transmembrane domain (TM-domain) of Archaeoglobus fulgidus LonB protease (Archaeoglobus fulgidus (AfLon)) was shown to result in uncontrollable activation of the enzyme proteolytic site and in vivo autolysis yielding a stable and functionally inactive fragment consisting of both α-helical and proteolytic domains (αP). The ΔTM-AfLon-S509A enzyme form, obtained by site-directed mutagenesis of the catalytic Ser residue, is capable of recombination with the αP fragment. The mixed oligomers were shown to be proteolytically active, which indicates a crucial role of subunit interactions in the activation of the AfLon proteolytic site. The thermophilic nature of AfLon protease was found to be due to the special features of the enzyme activity regulation, the structure of ATPase domain, and the quaternary structure.     

Long-term effects of graduated compression stockings on cardiorespiratory performance

The use of graduated compression stockings (GCS) in sport has been increasing in the last years due to their potential positive effects for athletes. However, there is little evidence to support whether these types of garments actually improve cardiorespiratory performance. The aim of this study was to examine the cardiorespiratory responses of GCS during running after three weeks of regular use. Twenty recreational runners performed three tests on different days: test 1) – a 5-min maximal effort run in order to determine the participants’ maximal aerobic speed; and tests 2) and 3) – a fatigue running test of 30 minutes at 80% of their maximal aerobic speed with either GCS or PLACEBO stockings at random. Cardiorespiratory parameters (minute ventilation, heart rate, relative oxygen consumption, relative carbon dioxide production, ventilatory equivalents for oxygen and carbon dioxide, and oxygen pulse) were measured. Before each test in the laboratory, the participants trained with the randomly assigned stockings (GCS or PLACEBO) for three weeks. No significant differences between GCS and PLACEBO were found in any of the cardiorespiratory parameters. In conclusion, the present study provides evidence that running with GCS for three weeks does not influence cardiorespiratory parameters in recreational runners.