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As a result of analyses of the effect of high voltage electrical stimulation (voltage of 330 V, frequency of 17 Hz, duration of 120 s) carried out ca. 40 min after slaughter on tenderness of bullocks (n=8) meat, lower values of the maximum shear force were obtained for the stimulated muscles (except for semimembranosus muscle stored for 144 h) as compared to its values noted for control muscles over the entire storage period. In addition, values of the maximum shear forces of stimulated, fresh m. longissimus dorsi and m. semimembranosus were alike and reached ca. 44 N. Results of analyses into the effect of storage time (144 h) on meat tenderness demonstrated that differences between the values of the maximum shear forces of the stimulated and control m. semimembranosus were decreasing along with time, whereas differences between the values of shear forces of m. longissimus dorsi (stimulated and control) were remaining at a constant level (ca. 30 N). The results obtained demonstrated that high voltage electrical stimulation, by means of an own-construction device, improves tenderness of the muscles examined.
When one leaf of a tomato plant is electrically-stimulated or heat-wounded, proteinase inhibitor genes are rapidly up-regulated in distant leaves. The identity of the systemic wound signal(s) is not yet known, but major candidates include hormones transmitted via the phloem or the xylem, the electrically-stimulated self-propagating electrical signal in the phloem (the action potential, AP), or the heat-wound-induced surge in hydraulic pressure in the xylem evoking a local change in membrane potential in adjacent living cells (the variation potential, VP). In order to discriminate between these signals we have adopted two approaches. The first approach involves applying stimuli that evoke known signals and determining whether these signals have similar effects on the “model” transcripts for proteinase inhibitors (pin) and calmodulin (cal). Here we show that a heat wound almost invariably evokes a VP, while an electrical stimulation occasionally evokes an AP, and both of these signals induce accumulation of transcripts encoding proteinase inhibitors. The second approach involves identifying the array of genes turned on by heat-wounding. To this end, we have constructed a subtractive library for heat-wounded tissue, isolated over 800 putatively up-regulated clones, and shown that all but two of the fifty that we have analyzed by Northern hybridization are, indeed, up-regulated. Here we show the early kinetics of up-regulation of three of these transcripts in the terminal (4th) leaf in response to heat-wounding the 3rd leaf, about 5 cm away. Even though these transcripts show somewhat different time courses of induction, with one peaking at 30 min, another at 15 min, and another at 5 min after flaming of a distant leaf, they all exhibit a similar pattern, i.e., a transient period of transcript accumulation preceding a period of transcript decrease, followed by a second period of transcript accumulation.
Study was based on hypothesis that electrical stimulation (ES) with parameters obtained from analysis of vagal afferent discharge fed state may fake brain with satiety state. We evaluated effect of denervation of vagal capsaicin-sensitive afferents on food intake and body weight in rats with ES of vagal nerves using microchip (MC). Group A was scheduled to MC implantation, B to sham operation only, C to MC implantation and capsaicin vagal deafferentation, and D to capsaicin denervation only. ES lasted 24 days. MC parameters were 0.05Hz, 0.1s, 0.55V. ES of left vagus significantly reduced total food intake as well as the mean daily intake in groups A and C in comparison to control and D group (ANOVA, F=18.55, p=0.0038). Body weight was lower in group A (346,2 g) and C (272,7 g) then in control (381,4 g) and D (356,8 g) (F=25.68, p=0.00068). Leptin decreased in C (165 pg/mL) in comparison to A (625 pg/mL), B (677 pg/mL), and D (612 pg/mL) (p<0,05), mainly due to ES (F=7.27, p=0.019). Glucose was decreased in A (F=5.55, p=0.036) - by 11 % and by 16% in C group. Proper vagal neuromodulation results in central and peripheral effects causing food intake and body weight downregulation.
This paper presents a discussion about the application of electricity that stimulates the growth of the plant to a great extent. This paper also demonstrates that exposure to the action of a high voltage electric field can be an effective tool for the enhancement of germination. The experiments were carried out on tomato seeds. A pilot treatment unit was developed and used for the study. Under normal conditions (no treatment), only about 76% of a reference sample of such seeds were germinated. Other seed samples were subjected to 50 Hz electric fields ranging from 10 to 30 kV cm-1 with exposure time ranging from 10 to 30 sec. In the optimum laboratory test, 100% of the seeds were germinated. The weight of the resulting tomato seedlings was greater than that of untreated ones. The germination tests proved the efficiency of this method. Ozone generation by partial discharges between seeds seems to be the main effective parameter that enhances the growth.
The motor points of the skeletal muscles, mainly of interest to anatomists and physiologists, have recently attracted much attention from researchers in the field of functional electrical stimulation. The muscle motor point has been defined as the entry point of the motor nerve branch into the epimysium of the muscle belly. Anatomists have pointed out that many muscles in the limbs have multiple motor points. Knowledge of the location of nerve branches and terminal nerve entry points facilitates the exact insertion and the suitable selection of the number of electrodes required for each muscle for functional electrical stimulation. The present work therefore aimed to describe the number, location, and distribution of motor points in the human forearm muscles to obtain optimal hand function in many clinical situations. Twenty three adult human cadaveric forearms were dissected. The numbers of primary nerves and motor points for each muscle were tabulated. The mean numbers and the standard deviation were calculated and grouped in tables. Data analyses were performed with the use of a statistical analysis package (SPSS 13.0). The proximal third of the muscle was the usual part of the muscle that received the motor points. Most of the forearm muscles were innervated from the lateral side and deep surface of the muscle. The information in this study may also be usefully applied in selective denervation procedures to balance muscles in spastic upper limbs.
Cholecystokinin like activity was measured in duodenal perfusates obtained from a 30 cm closed loop of the proximal duodenum in anaesthetized neonatal calves. The concentration and the output of the CCK activity in the duodenal perfusates increased significantly during pectrical stimulation of the vagus nerve, whereas the blood plasma concentration of CCK (external jugular vein and portal vein) remained unchanged and lower than that found in the duodenum. On the other hand, intravenous infusion of CCK raised the blood plasma but not the duodenal CCK concentrations. In conclusion, CCK-like activity is present in the duodenal lumen. The luminal release mechanism is at least partly regulated by the vagus nerves.
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