RECURSIVE FILTERING RADON-AMBIGUITY TRANSFORM ALGORITHM FOR DETECTING MULTI-LFM SIGNALS

In multi-LFM signal condition, Radon-Ambiguity Transform (RAT) of the strong LFM component has strong suppression effect on that of the weak LFM component. A method named as Recursive Filtering RAT (RFRAT) algorithm is proposed for solving this problem. By fully using of the Maximum Likelihood (ML) estimation value of the frequency modulation rate got by RAT, RFRAT can detect the noisy multi-LFM signals out step by step. The merit of this new method is validated by an illustrative example in low Signal-to-Noise-Ratio (SNR) condition.

基于Radon-ambiguity变换的ISAR成像算法

非匀速旋转目标和机动目标成像是逆合成孔径雷达 (ISAR)技术的一个重点和难点 ,经典的距离 -多普勒(RD)算法对其成像效果不佳。本文首先分析了ISAR成像回波信号模型 ,然后在对目标多普勒变化曲线作一阶近似的条件下提出了基于Radon Ambiguity变换 (RAT)的ISAR成像算法。最后进行仿真实验 ,仿真实验结果表明了该方法的有效性。

Effect of transforming growth factor beta and bone morphogenetic proteins on rat hepatic stellate cell proliferation and transdifferentiation

AIM: To explore different roles of TGF-β (transforming growth factor beta) and bone morphogenetic proteins (BMPs)in hepatic stellate cell proliferation and trans-differentiation.METHODS: Hepatic stellate cells were isolated from male Sprague-Dawley rats. Sub-cultured hepatic stellate cells were employed for cell proliferation assay with WST-1 reagent and Western blot analysis with antibody against smooth muscle alpha actin (SMA).RESULTS: The results indicated that TGF-β1 significantly inhibited cell proliferation at concentration as low as 0.1 ng/ml, but both BMP-2 and BMP-4 did not affect cell proliferation at concentration as high as 10 ng/ml. The effect on hepatic stellate cell trans-differentiation was similar between TGFβ1 and BMPs. However, BMPs was more potent at transdifferentiation of hepatic stellate cells than TGF-β1. In addition, we observed that TGF-β1 transient reduced the abundance of SMA in hepatic stellate cells.CONCLUSION: TGF-β may be more important in regulation of hepatic stellate cell proliferation while BMPs may be the major cytokines regulating hepatic stellate cell transdifferentiation.

Transforming growth factor β receptor Ⅱ expression inexperimental cryptorchidism and apoptosisin spermatogenic cells in rats

Objective: To study the transforming growth factor β receptor Ⅱ (TGFβ-R Ⅱ) expression in experimental cryptorchidism and apoptosis in spermatogenic cells in rats. Methods: The apoptosis of spermatogenic cells was detected by means of the terminal deoxynucleotldyl transferase mediated dUTP nick end lableling method (TUNEL) and the TGFβ-R Ⅱ expression was observed with the immunohistochemistry SABC methods. Results: There was a significant increase in the TGFβ-R Ⅱ expression in unilateral undescended testes (UUTs) compared with that in contralateral descended testes (CDTs, P<0.01). However, there was a significant and time-dependent increase in the mean apoptotic index in UUTs than in CDTs. Conclusion: TGFβ-R Ⅱ may play an important role in spermatogenic cell apoptosis.

Expression of transforming growth factor-β in local bony callus in traumatic brain injury combined with extremity fracture in rats

Objective To investigate gene expression of transforming growth factor-β(TGF-β)in local bony callus in tracumatic brain in jury combined with extremity long bone fracture in rats.Methods Eighty male SD rats were randomized into 2 even

机动目标一维距离像RAT法线性化补偿

研究了机动目标宽带线性调频脉冲回波全去斜率信号模型,根据速度和加速度的调频频谱展宽特点,提出了机动目标宽带一维距离像线性化调频回波模型,给出了Radon模糊图转换(RAT)法线性参数估计与运动补偿方法,并进一步分析了测速和测距误差。仿真实验验证了RAT法一维距离像线性化参数估计与补偿,表明该方法很好地解决了运动参数未知情况下机动目标的一维距离像频谱展宽问题。

Effects of Haobie Yangyin Ruanjian Decoction on hepatic fibrosis induced by carbon tetrachloride in rats

AIM:To explore the anti-fibrotic effect of Haobie Yangyin Ruanjian Decoction(HYRD)on CCl4-induced hepatic fibrosis in rats and its modulation on the transforming growth factor(TGF)β-Smad signaling pathway.METHODS:Fifty-six healthy Wistar rats were randomly divided into five groups:normal control group(n=6),CCl4-induced hepatic fibrosis group(n=14) and three treatment groups(the treated rats received HYRD via oral administration at daily dosages of 8.2,2.5 and 0.82 g/kg,respectively)of HYRD(n=12,respectively).Experimental hepatic fibrosis was induced by subcutaneous injection of carbon tetrachloride solution(CCl4 dissolved in peanut oil,4:6,V/V)with 0.5 mL/100 g body weight for the first time,and then 0.3 mL/100 g body weight twice a week for 8 wk.In the former 2 wk,rats were raised by feedstuffⅠ(80% corn meal,20%lard,0.5%cholesterol).After 2 wk,they were raised by feedstuffⅡ(corn meal and 0.5% cholesterol).Except for the control group,30%alcohol solution was given orally to each rat every other day from the beginning,1 mL for each rat.Liver function parameters and hepatic hydroxyproline content were detected by chromatometry.Serum levels of hyaluronic acid(HA),typeⅣcollagen(CIV),typeⅢprecollagen(PCⅢ)and laminin(LN)were assayed with radioimmunoassay.Deposition of collagen was observed with hematoxylin-eosin staining and collagen staining.Gene expression of TGFβ1 and Smad3 were detected with real-time reverse transcriptase-polymerase chain reaction and Western blotting,respectively.RESULTS:The serum levels of alanine transaminase and aspartate transaminase were increased in the model group compared with the control group(P<0.01),and they were decreased in the three treatment groups compared with the model group.The serum levels of total protein and albumin were decreased in the model group and increased in the three treatment groups.The hepatic hydroxyproline content and serum levels of PCⅢ,HA,LN and CIV were markedly increased in the model group compared with the control group,and decreased in the treatment groups.The gene expression of TGFβ1 and Smad3 was enhanced in the model group compared with the control group,and HYRD could down regulate their expression.CONCLUSION:HYRD can inhibit hepatic fibrosis induced by CCl4 in rats,which is probably associated with its down-regulation on fibrogenic signal transduction of TGFβ-Smad pathway.

Mitochondrial carnitine palmitoyl transferase-Ⅱ inactivity aggravates lipid accumulation in rat hepatocarcinogenesis

AIM To investigate the dynamic alteration of mitochondrial carnitine palmitoyl transferase Ⅱ(CPT-Ⅱ) expression during malignant transformation of rat hepatocytes.METHODS Sprague-Dawley male rats were fed with normal, high fat(HF), and HF containing 2-fluorenylacetamide(2-FAA) diet, respectively. According to the Hematoxylin and Eosin staining of livers, rats were divided into control, fatty liver, degeneration, pre-cancerous, and cancerous groups. Liver lipids were dyed with Oil Red O, CPT-Ⅱ alterations were analyzed by immunohistochemistry, and compared with CPT-Ⅱ specific concentration(μg/mg protein). Levels of total cholesterol(Tch), triglyceride(TG), and aminotransferases [alanine aminotransferase(ALT), aspartate aminotransferase(AST)] were determined by the routine methods.RESULTS After intake of HF and/or HF+2-FAA diets, the rat livers showed mass lipid accumulation. The lipid level in the control group was significantly lower than that in other groups. The changes of serum TG and Tch levels were abnormally increasing, 2-3 times more than those in the controls(P < 0.05). During the rat liver morphological changes from normal to cancer development process with hepatocyte injury, serum AST and ALT levels were significantly higher(4-8 times, P < 0.05) than those in the control group. The specific concentration of CPT-Ⅱ in liver tissues progressively decreased during hepatocyte malignant transformation, with the lowest CPT-Ⅱ levels in the cancer group than in any of the other groups(P < 0.05).CONCLUSION Low CPT-Ⅱ expression might lead to abnormal hepatic lipid accumulation, which should promote the malignant transformation of hepatocytes.

GFAP promoter directs lacZ expression specifically in a rat hepatic stellate cell line

AIM： The GFAP was traditionally considered to be a biomarker for neural gila （mainly astrocytes and nonmyelinating Schwann cells）. Genetically, a 2.2-kb human GFAP promoter has been successfully used to target astrocytes in vitro and in vivo. More recently, GFAP was also established as one of the several makers for identifying hepatic stellate cells （HSC）. In this project, possible application of the same 2.2-kb human GFAP promoter for targeting HSC was investigated. METHODS： The GFAP-lacZ transgene was transfected into various cell lines （HSC, hepatocyte, and other nonHSC cell types）. The transgene expression specificity was determined by X-gal staining of the β-galactosidase activity. And the responsiveness of the transgene was tested with a typical pro-fibrotic cytokine TGF-β1. The expression of endogenous GFAP gene was assessed by real-time RT-PCR, providing a reference for the transgene expression. RESULTS： The results demonstrated for the first time that the 2.2 kb hGFAP promoter was not only capable of directing HSC-specific expression, but also responding to a known pro-fibrogenic cytokine TGF-β1 by upregulation in a doseand time-dependent manner, similar to the endogenous GFAP. CONCLUSION： In conclusion, these findings suggested novel utilities for using the GFAP promoter to specifically manipulate HSC for therapeutic purpose.

Transplantation of human hepatocytes into tolerized genetically immunocompetent rats

AIM: To determine whether normal genetically immunocompetent rodent hosts could be manipulated to accept human hepatocyte transplants with long term survival without immunosuppression. METHODS: Tolerance towards human hepatocytes was established by injection of primary human hepatocytes or Huh7 human hepatoma cells into the peritoneal cavities of fetal rats. Corresponding cells were subsequently transplanted into newborn rats via intrasplenic injection within 24h after birth. RESULTS: Mixed lymphocyte assays showed that spleen cells from non-tolerized rats were stimulated to proliferate when exposed to human hepatocytes, while cells from tolerized rats were not. Injections made between 15 d and 17 d of gestation produced optimal tolerization. Transplanted human hepatocytes in rat livers were visualized by immunohistochemical staining of human albumin. By dot blotting of genomic DNA in livers of tolerized rats 16 weeks after hepatocyte transplantation, it was found that approximately 2.5 X 10(5) human hepatocytes survived per rat liver. Human albumin mRNA was detected in rat livers by RT-PCR for 15 wk, and human albumin protein was also detectable in rat serum. CONCLUSION: Tolerization of an immuno-competent rat can permit transplantation, and survival of functional human hepatocytes.

Establishment and characterization of a rat pancreatic stellate cell line by spontaneous immortalization

AIM: Activated pancreatic stellate cells (PSCs) have been implicated in the pathogenesis of pancreatic fibrosis and inflammation. Primary PSCs can be subcultured only several times because of their limited growth potential. A continuous cell line may therefore be valuable in studying molecular mechanisms of these pancreatic disorders. The aim of this study was to establish a cell line of rat PSCs by spontaneous immortalization.METHODS: PSCs were isolated from the pancreas of male Wistar rats, and conventional subcultivation was performed repeatedly. Telomerase activity was measured using the telomere repeat amplification protocol. Activation of transcription factors was assessed by electrophoretic mobility shift assay.Activation of mitogen-activated protein (MAP) kinases was examined by Western blotting using anti-phosphospecific antibodies. Expression of cytokine-induced neutrophil chemoattractant-1 was determined by enzyme immunoassay.RESULTS: Conventional subcultivation yielded actively growing cells. One clone was obtained after limiting dilution,and designated as SIPS. This cell line has been passaged repeatedly more than 2 years, and is thus likely immortalized.SIPS cells retained morphological characteristics of primary,culture-activated PSCs. SIPS expressed α-smooth muscle actin, glial acidic fibrillary protein, vimentin, desmin, type Ⅰ collagen, fibronectin, and prolyl hydroxylases. Telomerase activity and p53 expression were negative. Proliferation of SIPS cells was serum-dependent, and stimulated with platelet-derived growth factor-BB through the activation of extracellular signal-regulated kinase. Interleukin-1β activated nuclear factor-κB, activator protein-1, and MAP kinases.Interleukin-1β induced cytokine-induced neutrophil chemoattractant-1 expression through the activation of nuclear factor-κB and MAP kinases.CONCLUSION: SIPS cells can be useful for in vitro studies of cell biology and signal transduction of PSCs.

Detection and analysis of the effects of heat stress on EEG using wavelet transform ——EEG analysis under heat stress

Continuous wavelet transform (CWT) method has been applied to capture localized time-frequency information of rat electroencephalogram (EEG) in different vigilance states and analyze alterations in transients during awake, slow wave sleep (SWS), and rapid eye movement (REM) sleep stages due to exposure to high environmental heat. Rats were divided in three group (i) acute heat stress-subjected to a single exposure for four hours in the Biological Oxygen Demand (BOD) incubator at 38?C;(ii) chronic heat stress-exposed for 21 days daily for one hour in the incubator at 38?C, and (iii) handling control groups. After two hours long EEG recordings from young healthy rats, EEG data representing three sleep states was visually selected and further subdivided into 2 seconds long epoch. Powers of wavelet spectra corresponding to delta, theta, alpha, and beta bands at all scales and locations were computed and variation in their states investigated. The wavelet analysis of EEG signals following exposure to high environmental heat revealed that powers of subband frequencies vary with time unlike Fourier technique. Changes in higher frequency components (beta) were significant in all sleep-wake states following both acute and chronic heat stress conditions. Percentage power of different components of the four bands was always found to be varying at different intervals of time in the same signal of analysis.

The expression and antigenicity identification of recombinant rat TGF-β1 in bacteria

In order to study structure-function details of TGF-beta1, the recombinant mature form of rat TGF-beta1 was expressed in bacteria. Synthesis of the 112 amino-acid carboxyl-terminal part of TGF-beta1 (amino acid 279-390) was controlled by an inducible gene expression system based on bacteriophage T7 RNA polymerase. This system allowed an active and selective synthesis of recombinant TGF-beta1. The molecular weight of expressed TGF-alpha1 monomer determined on SDS-polyacrylamide gel under reducing conditions was about 13 kD. Serial detergent washes combined with a single gel-filtration purification step were sufficient to purify the expression product to homogeneity. Amino-terminal sequencing revealed that the N-terminal of the recombinant protein was identical to the published data. In Western blot analysis the recombinant polypeptide showed excellent antigenicity against polyclonal TGF-beta1 antibody. The mature recombinant rat TGF-beta1 expressed in this study provides a useful tool for future detailed structural and functional studies.

基于RAT变换的多LFM信号检测及参数估计

研究了相关解线调技术,对其存在的不足进行了分析。比较了Wigner-Ville方法与模糊函数在分析LFM信号时的差别,通过对比提出了基于RAT变换和快速解线调技术的新算法,最后通过计算机仿真验证了该算法的有效性。此方法解决了相关解线调的不足,减小了RWT变换的运算量,同时解决了单纯RAT法只能估计调频斜率的问题。

Integrated network pharmacology and experimental verification to explore the mechanism of Sangqi Qingxuan formula against hypertensive vascular remodeling

Objective: To investigate the bioactive components of Sangqi Qingxuan formula(SQQX), predict the pharmacological targets, and explore the mechanism of hypertensive vascular remodeling(HVR).Methods: Network pharmacology was adopted to predict how SQQX acts in HVR. The effectiveness was assessed by blood pressure measurements and pathological morphology observation based on a spontaneously hypertensive rat model, while the mechanism of SQQX on HVR was validated by immunohistochemistry(IHC) and western blot(WB) according to the results of network pharmacology.Results: There were 130 bioactive components of SQQX and 231 drug targets predicted by the Traditional Chinese Medicine Systems Pharmacology Database. Subsequently, 181 common targets were identified for SQQX against HVR, with TP53, MAPK1, and AKT1 as the core targets. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses was employed to identify the top 20 enriched functions and the top 20 pathways(P <.01). Finally, the key role of the ERK/MAPK signaling pathway in HVR was determined. The in vivo results suggested that SQQX reduced systolic blood pressure and increased the ratio of thoracic aortic wall thickness to lumen diameter. Additionally, compared with the model group, SQQX increased the expression of smooth muscle 22 alpha(IHC: P <.001;WB:P <.05) and decreased the expression of osteopontin(IHC: P <.001;WB: P <.05), ERK1/2(IHC: P <.001;WB: ERK1 & ERK2, all P <.05), p-ERK1/2(IHC: P <.001;WB: ERK1 & ERK2, all P <.05), and the ratio of pERK1/2 to ERK1/2 protein(IHC: P <.001).Conclusions: SQQX, which has multiple bioactive ingredients and potential targets, is an effective treatment for HVR. The mechanism of antihypertensive and vascular protection may be related to the inhibition of phenotypic transformation of vascular smooth muscle cells and the ERK/MAPK signaling pathway.

<i>In Vitro</i>Hippocampal Electrophysiology and <i>in Vivo</i>Quantitative EEG Revealed Robust Neurophysiological Effects of the Antivertigo-Agent Vertigoheel^&#174;in a Rat Study

Vertigo is a common symptom with impact on daily life. Vertigoheel&#174;(VH-04) has demonstrated to be effective for Vertigo in former studies. This paper aims to investigate the mode of action of the medicinal product VH-04 in the rat brain. In an in vitro study neurophysiological recording from hippocampal slices from adult male Sprague Dawley&#174;rats was performed in order to substantiate a possible direct effect on the brain of VH-04 in different concentrations. In an in vivo cross-over study with 11 Fischer 344&#174;?rats, a neurophysiological method was applied to systemically analyse VH-04’s activity in the rat brain. This method combines quantitative assessments of telemetrically transmitted field potentials after drug treatment with subsequent discriminant analysis to classify the compound. The database used for the analysis of classification contained numerous chemicals and medicinal products of different dosages, all tested in the same paradigm, which is continuous wireless monitoring of the EEG of freely moving rats before and after drug intake. Following single stimuli on the Schaffer collaterals in the presence of VH-04 in different concentrations, in vitro responses of pyramidal cells increased depending on the VH-04 concentration (0.25 - 4 ml/L). Results were statistically significant for concentrations above 2.5 ml/L. Long-term potentiation was only marginally affected. Out of several specific glutamate receptor antagonists the effect of VH-04 was only antagonized by AMPA and kainic acid receptor-mediated signalling. Their enhancement indicates better information processing in the hippocampus, a brain structure primarily involved in memory processes. The in vivo characterisation of VH-04-induced changes in EEG-signatures of four brain areas (the frontal cortex (FC), the hippocampus (HC), the striatum (ST) and the reticular formation (RF)) revealed a dose-dependent attenuation of delta, theta, alpha 2 and beta 1 waves. The subsequent discriminant function analysis classified the VH-04 EEG-signature into a subset of cognition-enhancing medicinal products.

Electroretinographic Oscillatory Potentials in Different Aged Rats: an Analysis in the Domains of Time and Frequency

Objectives: Electroretinographic Oscillatory Potentials (Ops) are considered to be the optimal parameter to study the retinal circulation disturbances the present we compared parameters of OPs between different aged rats under dark adaptationMethods: the scotopic ERG were performed in anaesthetized rats aged 3, 12,24 months. According a window of collective power spectrum field of the OPs was isolated by using the FFT and IFFT of the spectrum analysis program. The parameters in the time and frequency domains were calculated.Results: Results showed that the amplitudes of wavelets and the summed amplitudes of OPs declined with the increase of age. A reduction of the total power and dominated power of OPs was also found after the FFT. But implicit time of each OP and dominant frequency did not change obviously.Conclusions: The present study indicated that change of OPs of rat might be related to senile degeneration of the retina and circulative deficiency in retina in elder rats. Eye Science 1998; 14-27

基于上皮细胞-间充质转化的搜风愈喘方调控哮喘大鼠气道重塑的机制研究

目的探讨搜风愈喘方通过调控上皮细胞-间充质转化(EMT)抑制哮喘气道重塑的作用机制。方法将60只大鼠随机分为正常对照组、模型对照组、地塞米松组及搜风愈喘方高、中、低剂量组,每组10只。除正常对照组外,其余各组均采用卵清白蛋白(OVA)注射和雾化复制哮喘大鼠模型。各组大鼠给予相应药物灌胃21 d后处死大鼠,苏木素-伊红(HE)染色,观察肺组织病理形态学变化;透射电镜观察大鼠肺组织中上皮细胞超微结构情况;酶联免疫吸附测定法(ELISA)检测血清中的转化生长因子β1(TGF-β1)、白细胞介素17(IL-17)的含量;实时荧光定量聚合酶链式反应(RT-PCR)法检测肺组织匀浆中TGF-β1、α-平滑肌肌动蛋白(α-SMA)、E-钙黏蛋白(E-cadherin)和N-钙黏蛋白(N-cadherin)的mRNA表达。蛋白免疫印迹法(Western Blot)检测肺组织中TGF-β1、α-SMA、E-cadherin、N-cadherin蛋白表达水平。结果与正常对照组比较,模型对照组大鼠血清中TGF-β1、IL-17含量明显升高(P<0.01),肺组织中TGF-β1、α-SMA和N-cadherin mRNA和蛋白表达明显上调(P<0.01),E-cadherin mRNA和蛋白表达明显下调(P<0.01);HE染色显示气道壁及肺泡壁增厚,视野内可见大量炎症细胞浸润,炎症评分明显升高(P<0.01);透射电镜显示肺组织中上皮细胞水肿程度严重,胞内基质局部溶解、变淡,细胞器肿胀明显。与模型对照组比较,地塞米松组和搜风愈喘方各剂量组大鼠血清中TGF-β1、IL-17含量明显降低(P<0.05,P<0.01),TGF-β1、α-SMA和N-cadherin mRNA和蛋白表达明显下调(P<0.05,P<0.01),E-cadherin mRNA和蛋白表达明显上调(P<0.05,P<0.01);肺组织炎症细胞浸润减轻,支气管壁及肺泡壁增厚程度减轻,地塞米松组和搜风愈喘方高剂量组炎症评分降低(P<0.05);超微结构显示上皮细胞水肿程度明显减轻,细胞膜完整,胞内基质均匀,细胞器大多轻微肿胀。结论搜风愈喘方可降低TGF-β1水平,从而改善肺组织EMT,达到防治哮喘气道重塑的目的。

基于目标增强与鼠群优化的红外与可见光图像融合算法

针对传统红外与可见光图像融合结果存在目标模糊、信息丢失问题,提出一种基于目标增强与鼠群优化的红外与可见光图像融合方法,记为TERSFuse。为了减少融合结果中原始图像细节信息丢失,分别构建了红外对比度增强模块和基于亮度感知的可见光图像增强模块;利用拉普拉斯金字塔变换对红外和可见光增强图像进行多尺度分解,从而得到对应的高、低频图像;为了使融合结果充分保留原始图像信息,分别采用“最大绝对值”规则对红外和可见光高频图像进行融合以及通过计算权重系数对低频图像进行融合;设计了基于鼠群优化的图像重构模块以实现高频图像和低频图像重构权重的自适应分配,进而提高融合图像的视觉效果。为了验证所提算法优势,与7种经典融合算法进行比较,实验结果表明所提算法不仅具有良好的视觉效果,而且融合图像能够保留原始图像丰富的边缘纹理和对比度信息。