[Hypertensive disease and metabolic syndrome: application of metoprolol].

The aim of this work was to study effects of metoprolol on structural and functional characteristics of left ventricle (LV), cerebral circulation (CC), microcirculation (MC), lipid spectrum, rheologic and viscous properties of blood in patients with grade II-III hypertensive disease (HD) and metabolic syndrome. 65 patients in this condition (ESH/ESC, 2007) were given metoprolol (100-150 mg/d) and indapamide (1.5 mg/d) for 6 months. Daily AP profile, structural and functional characteristics of left ventricle were evaluated before and after therapy by echocardiography, cerebral dopplerography, conjunctival biomicroscopy, measurement of MC, hemorheologic parameters, blood lipid spectrum and glucose level. The target AP level and normalization of AP daily profile were achieved in 65% of the patients. The treatment improved myocardial contractility and diastolic function, decreased LV mass, corrected autoregulation of cerebral blood flow and MC. Metoprolol was shown to be metabolically inert. The study confirmed benefits of its application to the treatment of HD with metabolic syndrome.

Enhanced Cd2+ -selective root-tonoplast-transport in tobaccos expressing Arabidopsis cation exchangers.

Several Arabidopsis CAtion eXchangers (CAXs) encode tonoplast-localized transporters that appear to be major contributors to vacuolar accumulation/sequestration of cadmium (Cd(2+)), an undesirable pollutant ion that occurs in man largely as a result of dietary consumption of aerial tissues of food plants. But, ion-selectivity of individual CAX transporter types remains largely unknown. Here, we transformed Nicotiana tabacum with several CAX genes driven by the Cauliflower Mosaic Virus (CaMV) 35S promoter and monitored divalent cation transport in root-tonoplast vesicles from these plants in order to select particular CAX genes directing high Cd(2+) antiporter activity in root tonoplast. Comparison of seven different CAX genes indicated that all transported Cd(2+), Ca(2+), Zn(2+), and Mn(2+) to varying degrees, but that CAX4 and CAX2 had high Cd(2+) transport and selectivity in tonoplast vesicles. CAX4 driven by the CaMV 35S and FS3 [figwort mosaic virus (FMV)] promoters increased the magnitude and initial rate of Cd(2+)/H(+) exchange in root-tonoplast vesicles. Ion selectivity of transport in root-tonoplast vesicles isolated from FS3::CAX4-expressing plant lines having a range of gene expression was Cd(2+)>Zn(2+)>>Ca(2+)>>Mn(2+) and the ratios of maximal Cd(2+) (and Zn(2+)) versus maximal Ca(2+) and Mn(2+) transport were correlated with the levels of CAX4 expression. Root Cd accumulation in high CAX4 and CAX2 expressing lines was increased in seedlings grown with 0.02 muM Cd. These observations are consistent with a model in which expression of an Arabidopsis-gene-encoded, Cd(2+)-efficient antiporter in host plant roots results in greater root vacuole Cd(2+) transport activity, increased root Cd accumulation, and a shift in overall root tonoplast ion transport selectivity towards higher Cd(2+) selectivity. Results support a model in which certain CAX antiporters are somewhat more selective for particular divalent cations.

[Effect of eprosartan on microcirculation and blood rheology in patients with hypertensive disease]. / Vliianie éprosartana na mikrotsirkuliatsiiu i reologiiu krovi u bol'nykh gipertonicheskoi bolezn'iu.

The use of eprosartan (600-1200 mg/day for 4 weeks) in 28 patients with stage II hypertensive disease was associated with improvement of parameters of microcirculation and blood rheology.

[Effect of eprosartan on left ventricular diastolic function and cerebral hemodynamics in patients with hypertension]. / Vliianie éprosartana na diastolicheskuiu funktsiiu i tserebral'nuiu gemodinamiku u bol'nykh gipertonicheskoi bolezn'iu.

Eprosartan (600-1200 mg/day) was given for 4 weeks to 28 patients aged 32-62 years with stage II-III hypertension (WHO, 1999). Left ventricular diastolic function and cerebral blood flow were assessed by echocardiography and ultrasound dopplerography. Treatment with eprosartan was associated with improvements of impaired left ventricular diastolic function, structural and functional state of the heart, venous outflow from cerebral vessels, and restoration of unpaired autoregulation of cerebral blood flow. All these phenomena could potentially lead to normalization of cerebral tissue perfusion and stabilization of cerebral blood flow.

Tris Is a Competitive Inhibitor of K+ Activation of the Vacuolar H+-Pumping Pyrophosphatase.

The effects of a range of commonly used pH buffers on the hydrolytic activity of the plant vacuolar H+-transporting inorganic pyrophosphatase (V-PPase) from mung bean (Vigna radiata L.) hypocotyls were tested. All of the buffers inhibited K+ stimulation of the V-PPase, and the degree of inhibition was dependent on the concentrations of both the buffer and K+. The effects were dependent on the organic cation used in the buffers, and those tested inhibited in the order: Tris > Bis-Tris-propane > Bicine = Tricine > imidazole. Detailed studies revealed that a model in which Tris affects both the Km and Vmax for K+ stimulation provided an accurate description of the observed kinetics. The ability of different cations to stimulate the V-PPase was measured with a noncompeting buffer (5 mM imidazole-HCl) and the order of effectiveness was K+ = Rb+ > NH4+ >> Cs+ > Na+ > Li+, with the Km for K+ stimulation being about 1 to 2 mM. Published experiments performed in the presence of Tris were re-evaluated and all could be fitted to mixed inhibition kinetics, with kinetic parameters similar to those measured for the mung bean V-PPase. It is concluded that the variations in the published Km for K+ stimulation of the V-PPase are probably due to the effects of pH buffer cations and that the real value for this parameter is in the low millimolar range. The implications of this for regulation of the V-PPase by K+ in vivo and for the role of the enzyme in K+ transport into the vacuole are discussed.

The H(+)-pumping inorganic pyrophosphatase of the vacuolar membrane of higher plants.

The vacuolar H(+)-translocating pyrophosphatase (H(+)-PPase) of plants is a member of a new class of energized ion translocases. The development of our understanding of this enzyme is briefly reviewed, including the evidence for its physiological role in H(+)-pumping and K+ transport into the vacuole, the identity of the polypeptides components, the cloning and sequencing of a cDNA encoding the catalytic subunit, and the partitioning of function between cytosolic and membrane domains of the protein. Lack of information about the identity of the substrate, activators and inhibitors of the H(+)-PPase has been a major barrier to the latter work. The various analyses that have been done of the kinetics of the enzyme predict different sets of activators and inhibitors, but work with residue-specific covalent inhibitors is now being done to resolve this. The results suggest that Mg2PPi is the substrate and that Mg2+ is an activator, but whether other PPi complexes inhibit the enzyme is still to be established.

[Pure culture of bacteria using chromates and bichromates as hydrogen acceptors during development under anaerobic conditions]. / Chistaia kul'tura bakterii, ispol'zuiushchikh khromaty i bikhromaty v kachestve aktseptora vodoroda pri razvitii v anaérobnykh usloviiakh.

A pure bacterial culture utilizing chromates and bichromates as oxygen donors during growth on organic substances in anaerobic conditions was isolated from active ooze of sewage and industrial wastes containing a weak solution of chromates. A medium for growth of the bacterium was selected, and its morphological and cultural properties were studied. Chromates and bichromates are reduced only in anaerobic conditions by the bacterium or active ooze containing it, the hexavalent chromium becoming trivalent. The culture does not belong to any known species and has been therefore classed as Pseudomonas dechromaticans.