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51.
Obesity can activate the inflammatory signal pathway, induce in the body a state of chronic inflammation, and increase the excitability of the sympathetic nervous system, which may induce sympathetic neuropathic injury. The stellate sympathetic ganglia (SG) can express the P2X4 receptor, and the abnormal expression of the P2X4 receptor is related to inflammation. Imperatorin (IMP) is a kind of furan coumarin plant which has anti-inflammatory effects. This project aimed to investigate whether IMP can affect the expression of P2X4 receptors in the SG of obese rats to display a protective effect from high-fat-triggered cardiac sympathetic neuropathic injury. Molecular docking through homology modelling revealed that IMP had good affinity for the P2X4 receptor. Our results showed that compared with the normal group, the administration of IMP or P2X4 shRNA decreased sympathetic excitement; reduced the serum levels of triglyceride, total cholesterol, and lactate dehydrogenase; downregulated the expression of P2X4 receptors in SG; and inhibited the expression of inflammatory factors in the SG and serum of obese rats significantly. In addition, the expression of factors associated with the cell pyroptosis GSDMD, caspase-1, NLRP-3, and IL-18 in obese rats were significantly higher than those of the normal rats, and such effects were decreased after treatment with IMP or P2X4 shRNA. Furthermore, IMP significantly reduced the ATP-activated currents in HEK293 cells transfected with P2X4 receptor. Thus, the P2X4 receptor may be a key target for the treatment of obesity-induced cardiac sympathetic excitement. IMP can improve obesity-induced cardiac sympathetic excitement, and its mechanism of action may be related to the inhibition of P2X4 receptor expression and activity in the SG, suppression of cellular pyroptosis in the SG, and reduction of inflammatory factor levels.  相似文献   
52.
The present paper reports a 67-year-old male with pigmented dermatofibrosarcoma protuberans (Bednar tumor) on his right shoulder. The lesion had recurred twice. Clinically, the lesion was a reddish-brown, exophytic, multilobular, firm nodule with an irregular surface, which measured 6.4 x 4.2 cm. Histologically, the proliferated fibroblasts showed a cartwheel pattern and stained positively with CD34, similar to those of a common dermatofibrosarcoma protuberance. However, many melanin-bearing cells that were positive for the S-100 protein were found intermingled among the tumor cells. Based on these findings, we concluded that the clinical manifestations, level of malignancy, and cytological features, as well as the exception of melanin-bearing dendritic cells associated with pigmented dermatofibrosarcoma protuberans, suggest a common dermatofibrosarcoma protuberans. This supports the hypothesis that pigmented dermatofibrosarcoma protuberans is a pigmented variant of dermatofibrosarcoma protuberans. Thus, this type of tumor is not benign, but is an intermediate malignant tumor.  相似文献   
53.
It is hard to fly an RC helicopter desirably because of its dynamical instability and the fast responce of motion, so that some stabilizing control system has to be developed. The first step of design is the derivation of the mathematical model. Dynamics of a helicopter is much complicated due to the rotating blades and its validity is difficult to be evaluated. In this paper, the mathematical model of a hovering RC helicopter is derived and its validity is confirmed experimentally by designing the stabilizing control system of the gimbal equipment which has three degrees of freedom, rolling, pitching and yawing. At the same time, two kinds of small sensors are investigated and used to control the above equipment.  相似文献   
54.
A planar lightwave circuit (PLC) platform for optoelectronic hybrid integration shows potential for achieving 10 Gb/s operation. It uses AuSn bump-type bonding pads on a silica layer to decrease parasitic capacitance, which limited the CR time constant in the optical chip assembly region, and two-layer electrical wiring to reduce parasitic inductance, which caused resonance in the electrical circuit region. An arrayed receiver module fabricated by integrating a two-channel monolithic opto-electronic integrated circuit (OEIC) chip on the PLC platform demonstrated a 3 dB-bandwidth of 8 GHz in both channels, which is equal to the bandwidth of the OEIC chip. This shows the feasibility of using this PLC platform for multichannel 10 Gb/s operation. Furthermore, this PLC platform can combine the versatile optical circuit functions of a PLC, such as an arrayed-waveguide grating wavelength multiplexer, with the high-speed signal processing function of mature electronic IC circuits. Consequently, this platform is a key device that will lead to high-capacity optical signal processing systems using optical wavelength/frequency routing  相似文献   
55.
Evoked otoacoustic emissions (EOAEs) are considered to originate from outer hair cell movement and to be transmitted to the external auditory meatus through the ossicular chain and eardrum in a retrograde fashion. Therefore, the effect of the middle ear on EOAEs seems to be large. A sweep frequency middle-ear analyzer (MEA) has been developed that gives much more information on middle-ear dynamic characteristics than a conventional impedance meter. In this paper, applying our own EOAE measuring system and the MEA, EOAEs and middle-ear dynamic characteristics of normal subjects were measured, and an attempt was made to clarify the relationship between EOAEs and middle-ear dynamic characteristics. It is concluded that EOAEs are detected most distinctly at the middle-ear resonance frequency and that EOAEs are most detectable in normal subjects whose middle-ear mobility is moderate.  相似文献   
56.
57.
Multiple current dipole estimation using simulated annealing   总被引:4,自引:0,他引:4  
A method for estimating electrical current distribution in the human brain using a multiple current dipole model is presented. A cost function for estimating multiple dipoles is proposed and a simulated annealing algorithm is used to obtain an acceptable solution. Computer simulation is used to evaluate the effectiveness of this method  相似文献   
58.
This study was conducted to investigate the sialylations of glycoproteins in the nasal glands of patients with chronic sinusitis. Sialic acids were detected using lectin histochemistry, and the mRNA of sialyltransferase was evaluated by in situ hybridization histochemistry. Sambucus nigra agglutinin (SNA), which recognizes terminal sialic acids, strongly stained the glandular mucous cells of normal subjects, but not those of patients with chronic sinusitis. In situ hybridization histochemistry showed that the expression of alpha2,6 sialyltransferase mRNA was decreased in the secretory cells of patients with chronic sinusitis. Our present results suggest that a reduction in sialyltransferase activity at the mRNA level in the nasal glands may lead to the persistence of chronic sinusitis.  相似文献   
59.
We recently reported the isolation of the klotho gene, which in predominantly expressed in the kidney and involved in human aging phenotypes. In our previous studies, we demonstrated that the Klotho protein or its metabolites may possibly function as humoral factor(s) and protect against endothelial dysfunction because acetylcholine-mediated NO production in arteries was impaired in heterozygous klotho deficient mice (kl/+). However, the pathophysiological significance of the Klotho protein has not been clarified yet. In the present study, we examined expression of the klotho gene in the kidney of the following rat models for human diseases: (1) spontaneously hypertensive rat, (2) deoxycorticosterone acetate-salt hypertensive rat, (3) 5/6 nephrectomized rat, (4) non-insulin-dependent diabetes mellitus rat (the Otsuka Long-Evans Tokushima Fatty rat), and (5) rat with acute myocardial infarction. The expression levels of klotho mRNA in the kidney in these models were significantly lower than controls except for MI rats. This is the first report showing the expression of the klotho gene in the kidney is regulated under sustained circulatory stress such as long-term hypertension, diabetes mellitus, and chronic renal failure.  相似文献   
60.
The details of the simulated annealing algorithm proposed to estimate the parameters of multiple current dipoles using biomagnetic data are described. The effects of the choices of such numerical conditions as the amount of estimate transitions, the equilibrium criterion, and the temperature decrement on the algorithm's performance are discussed. Incorrect results from the computer simulation obtained with inappropriate choices of such conditions are presented. The verification of a near-optimum convergence by reheating and reannealing is demonstrated. A modification of this algorithm is proposed for implementation by parallel computer, and the validity of this parallel algorithm is demonstrated by computer simulation.  相似文献   
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