The application of a wavelet filtering method in magneto-acousto-electrical tomography.

Magneto-acousto-electrical tomography (MAET), which couples ultrasound imaging with electrical impedance tomography, is an electrical property imaging method which is expected to have a wide range of clinical applications, including the early detection of breast and liver cancers. Obviously, as a coupled imaging method, how to improve the signal-to-noise ratio (SNR) is a key issue in the imaging process. In this paper, a wavelet filtering method is introduced into MAET, which includes the filtering effect of the db6 wavelet, and its filtering effect at different decomposition levels. At the same time, based on the Lorentz reciprocity theorem, the wave equation satisfied by the detected voltage obtained by electrode was deduced. We also built an experimental platform to acquire signals by keeping the position of the target unchanged and moving the ultrasound transducer along the trajectory of a circular arc. The experimental results show that the wavelet filtering scheme proposed in this paper improves the SNR of the detected signal of 15.1 dB, and the images of electrical properties of the phantom and pork from isolated tissues were realized by the filtered signal of the db6 wavelet and time reversal method, which reflects the interface of electrical conductivity change of tissues. This scanning method, of fixing the target body and rotating the transducer, can effectively reduce the error and noise caused by the movement of the detection electrodes in the experiment. The filtering technique and imaging algorithm proposed in this paper have improved the SNR and contrast of the images. Thus, the images of the low conductivity phantom with 0.2 S m-1and isolated tissue were obtained, which indicates that the MAET has good prospects in clinical applications.

[Effects of geniposide on treating experimental chronic prostatitis rats].

OBJECTIVE: To study the effect of geniposide on treating experimental CP rats. METHOD: The animal model of CP was made with rats by injecting hemorrhoid injection. Rats in experiment group were randomly devided into model group, Qianliekang tablets group (2 g x kg(-1)) and geniposide high, middle, low dose groups (20, 10, 5 mg x kg(-1)). Subsequently, the state of all rats, prostate index, WBC and lecithine corpuscle, LDH5/LDH1, and prostatic histopathological changes were observed. Count of total cellular score (TCS) and quantitation of inflammatory cell, fibroblasts, glandular organ, calculation of glandular cavity area, and their changes of morphology were analyzed. RESULT: Compared with model group, the prostate index, WBC and LDHS/LDH1 of the rats in Qianliekang tablets group, high dose geniposide group and middle dose geniposide group were significantly decreased, while the quantities of lecithine corpuscle were remarkably increased (P < 0.01 or P < 0.05). Compared with model group, the number of inflammatory cells and fibroblasts in Qianliekang tablets group, high dose geniposide group were decreased, and the quantity of glandular organ and area of glandular cavity in these groups were increased (P < 0.05 or P < 0.01). CONCLUSION: Geniposide of high and middle dose can reduce leucocytes infiltration, restrain the hyperplasia of fibrous tissue, and recover the secretion function of prostate. It show that geniposide is significantly potential to cure rats which are exposed to chronic prostatitis.

[Study of geniposide-acid on anti-inflammatory action for adjuvant-induced arthritis rats and mechanism of synoviocyte apoptosis in vitro].

OBJECTIVE: To study the effect of geniposide-acid(GA) on the anti-inflammatory action for adjuvant-induced arthritis (AA) rats and the proliferation of synoviocytes in AA rats and the feasible mechanism of apoptosis in vitro. METHOD: Forty-eight health male Wistar rats were divided randomly into six groups and were administered respectively with 200, 100, 50 mg x kg(-1) GA and 0.75 mg x kg(-1) MTX and normal sodium (normal or model control group) for four weeks when right posterior paw pads of rats excluding normal control group were injected intrademally with complete Freund's adjuvant after 19 days. The left posterior paws swelling degree, swelling inhibition ratio and arthritis index of secondary inflamation were detected. The TNF-alpha and IL-1beta proteins in serum of rats were assayed by enzyme linked immunosorbent assay (ELISA) kits. The synovial fibroblasts of AA rats were exposed to 1-4 micromol x L(-1) GA or 4 micromol x L(-1) MTX. The effect of GA on the proliferation of synoviocytes was detected by MTT assay. The morphologic change of apoptosis cells was observed by Hoechst/PI double stainning and fluorescence microscope. The rate of apoptosis cells was analyzed by flow cytometry. The mRNA expresstion of Bcl-2 and Bax gene was detected by reverse transcription PCR (RT-PCR). RESULT: 200 mg kg(-1) or 100 mg kg(-1) GA could decrease significantly the paw swelling degree, arthritis index and the level of TNF-alpha and IL-1beta proteins in serum of AA rats (P < 0.05 or P < 0.01) with 25.4%, 21.37% of the swelling inhibition ratio respectivly, 34.61%, 28% of protein inhibition ratio of TNF-alpha and 29.05%, 21.65% of that of IL-1beta. GA(1-4 micromol x L(-1)) inhibitated significantly the proliferation of synoviocytes culcured for 5 days. Flow cytometry showed that 1, 2, 4 micromol x L(-1) GA increased obviously the rate of apoptosis cells, the apoptosis ratios were 15.8%, 24.3%, 40.7% respectivly (P < 0.01). RT-PCR showed GA could decrease the expression level of Bcl-2 gene but increase that of Bax gene (P < 0.05 or P < 0.01). CONCLUSION: GA could inhibit the secondary inflamation of AA rats and decrease the level of TNF-alpha and IL-1beta protein in the AA rats serum. GA could inhibit the proliferation of AA rat synoviocytes in vitro and induce apoptosis which mechanism was concerned with down-regulating the mRNA expression of Bcl-2 and up-regulating that of Bax.

[Effect of geniposide on serum IL-1beta and TNF-alpha of rheumatoid arthritis rats].

OBJECTIVE: To study the effect of geniposide on serum IL-1beta and TNF-alpha levels of rheumatoid arthritis rats, as well as the mechanism of this drug. METHOD: To establish an experimental rat model of type II collagen-induced arthritic (CIA). The inhibitory effects on paw edema were observed, and serum IL-1beta and TNF-alpha levels were determined in experimental rats. RESULT: Compared with the model, geniposide delayed the starting time of right paw edema significantly, and the levels of serum IL-1beta and TNF-alpha were significantly decreased by geniposide at high dose or medium dose (P < 0.01). CONCLUSION: Geniposide can lower serum IL-1beta and TNF-alpha levels in rheumatoid arthritis rats. The effect may be close related to inhibitory development of rheumatoid arthritis by the agent.