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Number of results: 18
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Abstract

European beaver (Castor fiber), the largest rodent species inhabiting a wide area of Eurasia, feeds mainly on dry parts of plants, bark or wood. Such kind of nourishment needs to be properly digested in each part of the gastrointestinal tract. The time of stomach digestion, which directly influences all the following steps of the digestion process, is precisely controlled by the pylorus and its innervation. However, virtually no data is available on the organization of the enteric nervous system in most of the wild animal species, including beavers. On the other hand, a pecu- liar diet consumed by beavers, suggests that the arrangement of their stomach intramural nerve elements can be atypical. Therefore, the present study investigated the distribution and chemical coding of neurons and nerve fibers in the pylorus of the European beaver. The experiment was performed on stomachs obtained from a group of 6 beavers caught in Northeastern region of Poland (due to beaver overpopulation). Pyloric wall tissue cryosections were double immunostained with a mixture of antibodies against pan-neuronal marker PGP 9.5 (to visualize enteric neurons) and ChAT (cholinergic marker), nNOS (nitrergic marker), SP, CGRP, Gal (peptidergic markers). Confocal microscopy analysis revealed that the majority of enteric nerve cells were clustered forming submucosal and myenteric ganglia and all the studied substances were expressed (in various amounts) in these neurons. We conclude, that the anatomical arrangement and chemical coding of intramural nerve elements in the beaver pylorus resemble those found in other mammalian species.
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Abstract

The present study investigated the expression of androgen receptor (AR) in neurons of the anterior pelvic ganglion (APG) and celiac-superior mesenteric ganglion (CSMG; ganglion not involved in the innervation of reproductive organs) in the male pig with quantitative real-time PCR (qPCR) and immunohistochemistry. qPCR investigations revealed that the level of AR gene expression in the APG tissue was approximately 2.5 times higher in the adult (180-day-old) than in the juvenile (7-day-old) boars. Furthermore, in both the adult and juvenile animals it was sig- nificantly higher in the APG than in CSMG tissue (42 and 85 times higher, respectively). Immu- nofluorescence results fully confirmed those obtained with qPCR. In the adult boars, nearly all adrenergic (DβH-positive) and the majority of non-adrenergic neurons in APG stained for AR. In the juvenile animals, about half of the adrenergic and non-adrenergic neurons were AR-posi- tive. In both the adult and juvenile animals, only solitary CSMG neurons stained for AR. The present results suggest that in the male pig, pelvic neurons should be considered as an element of highly testosterone-dependent autonomic circuits involved in the regulation of urogenital func- tion, and that their sensitization to androgens is a dynamic process, increasing during the prepu- bertal period.
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Abstract

The presented paper concerns a novel concept of hybrid piezoelectric motor based on electroactive lubrication principle. Its structure is combined of quasi-static and resonance piezoelectric actuators, synchronizing their work to generate the rotary movement. The hybrid motor topology is compared to the existing piezoelectric motors, regarding its field of applications in embedded systems with very high security requirements. The electroactive lubrication principle is briefly presented with regards to optimization of the hybrid motor. The performance principle of the hybrid motor is described in terms of its working cycle. The assembling process of the prototype hybrid motor is briefly explained with emphasis put on the frequency and impedance tuning of the applied quasi-static and resonance piezoelectric actuators. Next, the hybrid motor power supply system is described and chosen measured performance characteristics are presented. Finally, conclusions concerning the features of the tested prototype hybrid motor and possible solutions of the faced issues, during assembling and testing, are presented.
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Abstract

Autonomic nervous system of the pelvis is still poorly understood. Every year more and more pelvic procedures are carried out on patients suff ering from diff erent pelvic disorders what leads to numerous pelvic dysfunctions. Authors tried to review, starting from historical and clinical background, the most important reports on anatomy of the pelvic autonomic plexuses. We also pay attention to complete lack of knowledge of students of medicine on the autonomic nervous structures in the area studied. We present anatomical description of the pelvic plexuses including their visceral branches and anatomy of surrounding pelvic tissues which still remains unclear. More and more attention is paid to the topography of the plexuses specially because of new pain releasing techniques — neurolysies.
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