β3-Adrenergic Regulation of L-Type Ca2+ Current and Force of Contraction in Human Ventricle

β₃-Adrenergic receptor (β₃-AR) is expressed in human atrial and ventricular tissues. Recently, we have demonstrated that it was involved in the activation of L-type Ca²⁺ current (I _Ca,L) in human atrial myocytes and the force of contraction of human atrial trabeculae. In the present study, we examined the effect of β₃-AR agonist CGP12177 which also is a β₁-AR/β₂-AR antagonist on I _Ca,L in human ventricular myocytes (HVMs) and the force of contraction of human ventricular trabeculae. CGP12177 stimulated I _Ca,L in HVMs with high potency but much lower efficacy than isoprenaline. The β₃-AR antagonist L-748,337 inhibited the effect of CGP12177. CGP12177 and L748,337 competed selectively on β₃-ARs because L748,337 had no effect on isoprenaline-induced stimulation of I _Ca,L, while CGP12177 completely blocked the effect of isoprenaline. The activation of β₃-ARs by CGP12177 does not involve the activation of G_i proteins because CGP12177 had no effect on forskolin-induced stimulation of I _Ca,L. CGP12177 had no effect on the force of contraction of human ventricular trabeculae. L-NMMA, an inhibitor of NO synthase, and IBMX, a nonselective inhibitor of phosphodiesterases, did not potentiate the effect of CGP12177 either on contraction of human ventricular trabeculae or on I _Ca,L in HVMs. We conclude that in human ventricles β₃-AR activation has no inotropic effect, while it slightly increases I _Ca,L. In contrast to human atrium, the activation of β₃-ARs in human ventricle is not accompanied by increased activity of phosphodiesterases.     

Bacterial fermentation and isotope labelling optimized for amyloidogenic proteins

We developed a cost sensitive isotope labelling procedure using a fed-batch fermentation method and tested its efficiency producing the ¹⁵N-, ¹³C- and ¹⁵N/¹³C-labelled variants of an amyloidogenic miniprotein (E5: EEEAVRLYIQWLKEGGPSSGRPPPS). E5 is a surface active protein, which forms amyloids in solution. Here, we confirm, using both PM-IRRAS and AFM measurements, that the air–water interface triggers structural rearrangement and promotes the amyloid formation of E5, and thus it is a suitable test protein to work out efficient isotope labelling schemes even for such difficult sequences. E. coli cells expressing the recombinant, ubiquitin-fused miniprotein were grown in minimal media containing either unlabelled nutrients, or ¹⁵N-NH₄Cl and/or ¹³C-D-Glc. The consumption rates of NH₄Cl and D-Glc were quantitatively monitored during fermentation and their ratio was established to be 1:5 (for NH₄Cl: D-Glc). One- and two-step feeding schemes were custom-optimized to enhance isotope incorporation expressing five different E5 miniprotein variants. With the currently optimized protocols we could achieve a 1.5- to 5-fold increase of yields of several miniproteins coupled to a similar magnitude of cost reduction as compared to flask labelling protocols.     

Correction: Neutralizing Antibody Response after Intramuscular Purified Vero Cell Rabies Vaccination (PVRV) in Iranian Patients with Specific Medical Conditions

Objective

Post exposure prophylaxis using one of the WHO-approved vaccines is the method of choice for preventing rabies. Abnormal immune function in patients with some specific medical conditions, such as pregnancy, chronic hepatitis B virus infection, different types of cancers like lymphoma, diabetes I and II, corticosteroid consumption by patients with rheumatoid arthritis and lupus erythematosus, could impair the immunologic response to various vaccines. The immune response to rabies vaccination has never been examined in patients with any of these described medical conditions. This study purposed to evaluate the neutralyzing antibody response after vaccination with purified Vero cell rabies vaccine (PVRV) according to the WHO-recommended Post–Exposure Prophylaxis (PEP) "ESSEN" regimen.

Methods

Thirty healthy volunteers and 50 volunteers with different medical conditions who were exposed to a suspected rabid animal in the 2nd or 3rd category of exposure received 5 doses of PVRV under the ESSEN protocol. Three blood samples were collected on days 0 (before the first dose), 14, and 35. The anti-rabies antibody titer was measured using the Rapid Fluorescent Foci Inhibition Test (RFFIT) and an ELISA Bio-Rad, Platelia, Rabies II kit.

Results

All subjects reached NAb titers above 0.5 IU/ml by day 14 after vaccination. On day 35 (1 week after receiving the last rabies vaccine), anti-rabies antibodies were in the protective level (>0.5 IU/ml) in both groups. There was no statistically significant difference in anti-rabies antibody response due to the type of exposure (category 2 or 3), and successful seroconversion was confirmed in both groups.

Conclusion

In conclusion, the ESSEN protocol using the PVRV vaccine is sufficient for rabies prophylaxis in patients with specific medical conditions.     

Pulvinus activity,leaf movement and leaf water-use efficiency of bush bean (<Emphasis Type="Italic">Phaseplus vulgaris</Emphasis> L.) in a hot environment

Pulvinus activity of Phaseolus species in response to environmental stimuli plays an essential role in heliotropic leaf movement. The aims of this study were to monitor the continuous daily pulvinus movement and pulvinus temperature, and to evaluate the effects of leaf movements, on a hot day, on instantaneous leaf water-use efficiency (WUE_i), leaf gas exchange, and leaf temperature. Potted plants of Phaseolus vulgaris L. var. Provider were grown in Chicot sandy loam soil under well-watered conditions in a greenhouse. When the second trifoliate leaf was completely extended, one plant was selected to measure pulvinus movement using a beta-ray gauging (BRG) meter with a point source of thallium-204 (²⁰⁴Tl). Leaf gas exchange measurements took place on similar leaflets of three plants at an air temperature interval of 33–42°C by a steady-state LI-6200 photosynthesis system. A copper-constantan thermocouple was used to monitor pulvinus temperature. Pulvinus bending followed the daily diurnal rhythm. Significant correlations were found between the leaf-incident angle and the stomatal conductance (R ² = 0.54; P < 0.01), and photosynthesis rate (R ² = 0.84; P < 0.01). With a reduction in leaf-incidence angle and increase in air temperature, WUE_i was reduced. During the measurements, leaf temperature remained below air temperature and was a significant function of air temperature (r = 0.92; P < 0.01). In conclusion, pulvinus bending followed both light intensity and air temperature and influenced leaf gas exchange.     

Differential protein synthesis after red light illuminations in germinating fern spores

The effects of red and far red illuminations were studied in spores of the dark germinatingPteridium aquilinum and that of the light dependently germinatingDryopteris filix-mas. Proteins were analysed by electrophoresis according to their molecular weights. The isoesterases were separated by gel electrofocusing. In both species we found two newly synthesized protein bands, probably controlled by the presence of active phytochrome. One of these seems to be identical, the other is different in the two species. Phytochrome control was also detected in the esterase isoenzyme pattern.     

Urethane and hydroxyurethane induce sister-chromatid exchanges in cultured human lymphocytes.

Both urethane and hydroxyurethane induced sister-chromatid exchanges (SCE) in cultured human lymphocytes. Aroclor-induced rat-liver microsome fraction deactivated rather than activated these two agents in the lymphocyte system.