Inhibitory effect induced by fractional Gaussian noise in neuronal system

We discover a phenomenon of inhibition effect induced by fractional Gaussian noise in a neuronal system. Firstly,essential properties of fractional Brownian motion(fBm) and generation of fractional Gaussian noise(fGn) are presented,and representative sample paths of fBm and corresponding spectral density of fGn are discussed at different Hurst indexes.Next, we consider the effect of fGn on neuronal firing, and observe that neuronal firing decreases first and then increases with increasing noise intensity and Hurst index of fGn by studying the time series evolution. To further quantify the inhibitory effect of fGn, by introducing the average discharge rate, we investigate the effects of noise and external current on neuronal firing, and find the occurrence of inhibitory effect about noise intensity and Hurst index of f Gn at a certain level of current. Moreover, the inhibition effect is not easy to occur when the noise intensity and Hurst index are too large or too small. In view of opposite action mechanism compared with stochastic resonance, this suppression phenomenon is called inverse stochastic resonance(ISR). Finally, the inhibitory effect induced by fGn is further verified based on the inter-spike intervals(ISIs) in the neuronal system. Our work lays a solid foundation for future study of non-Gaussian-type noise on neuronal systems.

Inhibitory Effects of Bacillus subtilis on Staphylococcus aureus

[Objective] To produce drug resistance, seek non-toxic environmental so as to change the current biological drugs that did not excessive use of antibiotics. [Methods] A strain of Bacillus was purified and isolated from fresh and healthy in- testines of grass carps. Biochemical identification was carried out by conventional bacterial biochemical test method. Two pairs of primers were designed, 16S rRNA detection and sequencing analysis were carried out. Drug sensitive test was carried out by agar diffusion method. In vitro inhibition test on Staphylococcus aureus was carried out by Oxford cup method. [Results] The isolated bacterium had basically the same biochemical characters as Bacillus subtilis; and the homology reached 100%. Thus, the isolated bacterium was identified to be Bacillus subtilis. It was insensitive to amoxicillin, ampicillin, penicillin G and so on, but sensitive to amikacin, cefalexin, ciprofloxacin and cefradine. The inhibitory effects of Bacillus subtilis on Staphylococ- cus aureus were significant. The minimum inhibitory concentration （MIC） was 2.8×10^8×2^-5/ml and minimum bactericidal concentration （MBC） was 2.8×10^8×2^-2/ml. [Conclusions] The isolated Bacillus subtilis could be used to prevent and control diseases caused by Staphylococcus aureus, and reduce the abuse of antibiotics.

Inhibitory Effects of Original Nano-Cu_2O Drug and Nano-Cu_2O Suspension on Snake Melon Botrytis cinerea

The drug-containing culture medium method for the test of toxicity was adopted to compare inhibitive effects of original nano-Cu2O drug and nano-Cu2O suspension, and nano-Cu2O drug has better inhibitive effects on snake melon Botry- tis cinerea than original nano-Cu2O drug with the same mass concentration, and inhibitory effects are positively correlated with concentration. Correlation coefficients of the toxicity regression equation are 0.892 2 and 0.996 1, effective concentration EC50 of original nano-Cu2O drug and that of nano-Cu2O suspension are 3 948.9 and 167.9 mg/kg. Original nano-Cu2O drug has an inhibitive effect on snake melon Botrytis cinerea, but the inhibition of nano-Cu2O suspension is more obvious.

Inhibitory Effects of Extracts from Marigold(Tagetes patula) against Tomato Fusarium Wilt

[ Objective ] The study aimed to explore a new way for the control of Tomato Fusarium Wilt. [ Method ] Different solvents were used to prepare the ex-tracts of marigold, and the inhibitory effects of different extraction solvents and different extraction parts of marigold against Tomato Fusar/um Wilt were compared. [ Result ] Among different solvent extracts of marigold, chloroform extracts had the strongest inhibitory effects against the growth of the pathogen; among the chloro- form extracts from different parts of marigold, root extract had the most obvious inhibitory effect against the disease, followed by flower and leaf extracts, and the in- hibitory effect of stem extract was the weakest. [ Conclusion ] The active components of marigold have inhibitory effect against Tomato Fusarium Wilt, and the plant has good development prospects and application value.

The Inhibitory Effect of Extracts From Fructus lycii and Rhizoma polygonati on in vitro DNA Breakage by Alternariol

Alternariol caused DNA single-strand breakage. Conversion of the closed circular double-stranded supercoiled DNA (pBR 322) to the nicked circular form and linear form was used to investigate the effect of extracts of some Chinese medical herbs on DNA nicking induced by alternariol. Some substances in the extracts of Rhizoma polygonati (RP) and Fructus lycii (FL) were shown to protect DNA from the attack by alternariol.Some substance in the RP may bind to plasmid DNA, and this binding reduces the electrophoretic mobility of DNA. These results indicate that substances from FL and RP may be used as DNA protectors. It is possible that they play an important role in preventing cancer.

THE LOCALIZATION OF ADRENOMEDULLIN IN RAT KIDNEY TISSUE AND ITS INHIBITORY EFFECT ON THE GROWTH OF CULTURED RAT MESANGIAL CELLS

OBJECTIVE: To observe the localization of adrenomedullin (AM) in rat kidney tissue and its inhibitory effect on the growth of cultured rat mesangial cells (MsC). METHODS: A monoclonal antibody against AM developed by our laboratory was used to detect the localization of AM protein in rat kidney tissue by avidin-biotin complex immunohistochemistry. The expressions of AM and its receptor CRLR mRNA on cultured glomerular epithelial cells (GEC) and MsC were investigated by Northern blot assay, and the possible effect of AM secreted by GEC on MsC proliferation was observed using [3H]thymidine incorporation as an index. RESULTS: A specific monoclonal antibody against AM was succesfully developed. AM was immunohistochemically localized mainly in glomeruli (GEC and endothelial cells), some cortical proximal tubules, medullary collecting duct cells, interstitial cells, vascular smooth muscle cells and endothelial cells. Northern blot assay showed that AM mRNA was expressed only on cultured GEC, but not on MsC, however, AM receptor CRLR mRNA was only expressed on MsC. GEC conditioned medium containing AM can inhibit MsC growth and AM receptor blocker CGRP8-37 may partially decreased this inhibitory effect. CONCLUSION: AM produced by GEC inhibits the proliferation of MsC, which suggests that AM as an important regulator is involved in glomerular normal physiological functions and pathologic processes.

Inhibitory Effect of Extracellular Polysaccharide EPS-II from Pseudoalteromonas on Candida adhesion to Cornea in vitro

Objective Fungal keratitis（FK） is a vision-threatening infection,whose treatment requires more effective and safer anti-fungal agent exploitation urgently.With this aim,we focused on the effect of an extracellular polysaccharide on fungal adhesion to human corneal epithelial cells.Methods We performed the cytotoxicity assays of the extracellular polysaccharide EPS-II from an antarctic bacterium Pseudoaltermonas and evaluated its inhibitory effect on Candida albicans cells＇ adherence to human corneal epithelial cells（HCECs）.Results EPS-II,which displayed minor cytotoxicity but also promoted proliferation of HCECs,could inhibit the adherence of yeast cells to HCECs in a dose-dependent manner.EPS-II could also suppress the subsequent PI3K/AKT signaling pathway,and thereby decrease the expression of early inflammatory cytokines.Conclusions ExtracellularpolysaccharideEPS-IIwassuggestedasanewnaturalagentforattenuatingFK.

Chemopreventive and Growth Inhibitory Effects of Selenium

There is very convincing evidence that a high dietary level of selenium substantially reduces the incidence of a wide variety of animal cancers. The human epidemiological evidence is less clear cut, but overall suggests that selenium may be protective: the evidence is strongest in men in relation to gastro-intestinal cancers. There is evidence that dietary selenium compounds reduce the formation of DNA adducts by carcinogens. Selenium compounds also inhibit growth in vitro and induce apoptosis. In general, there is a good correlation between the effectiveness of selenium compounds in chemoprevention and growth inhibition, implying that the mechanisms of growth inhibition and chemoprevention may be similar and that a major factor in the chemopreventive effects of selenium compounds in vivo is their ability to retard outgrowth of pre-malignant cells. Various hypotheses have been advanced as to how selenium compounds might prevent tumour cellgrowth. One is that they cause apoptosis by inducing oxidative stress. However, we have shown that the most potent selenium compound, selenodiglutathione (SDG), a natural metabolite of selenite, does not induce oxidative stress, at least not in the sarne way as other oxidants such as H2O2 and diamide. Firstly, a partially selenium-resistant variant cell line does not show increased resistance to H2O2. Moreover, SDG does not induce widespread tyrosine phosphorylation, including MAP and SAN kinases, like other oxidants such as H2O2 and diamide and its effects are not reversed by pretreatment with the tyrosine kinase inhibitor, herbimycin. Our experiments with the selenium-resistant variant suggest that a novel selenium-binding protein may be involved in growth inhibition by selenium

Growth Inhibitory Effects of Garlic Polysaccharide on Human HepG2 Cells

[Objective] The growth inhibitory effects of garlic polysaccharide(GPS) on human Hep G2 cells were evaluated in this paper. [Method] Hep G2 cells were treated with GPS for 48 h for morphology assay by transition electron microscope. Anti-proliferative effects with the same treatment for 24 hand 48 h were assayed by MTT method.Cell cycle distribution and apoptosis assay of treated cells were performed in flow cytometry. [Result] The results showed that GPS enhanced growth inhibitory effect on Hep G2 cells in a time-and dose-dependent manner. PI(Propidium iodide)/Annexin V staining analyzed by FCM(flow cytometry) demonstrated that GPS has a cytotoxic effect on tumor cells. Cell cycle arrest of Hep G2 treated with GPS occurred in G2 phase. [Conclusion] This study suggests that GPS could exert an antitumor effect and could be used as a therapeutic agent for live cancer.

Inhibitory effect of parvovirus H-1 on the formation of colonies of human hepatoma cell line in vitro and its tumors in nude mice

The inhibitory effect of parvovirus H-1 on the colonyforming ability in vitro of QGY-7703, a cultured human hepatoma cell line, and on the formation and growth of its tumors in nude mice was studied. With higher multiplicity of infection (MOI) of H-1 given, survival of the QGY-7703 cells was found to be decreased. H-1 DNA amplification level at 30 h postinfection(p.i.) was detected to be 7.4 times higher than that at 2 h by dispersed cells assay, while the cells were delayed to enter into S phase.Plaques were formed in the indicator cells (new-born human kidney cell line, NBK) by progeny H-1 virus particles released from the infected QGY-7703 cells by infectious cell center assay. The formation of tumors in nude mice by QGY-7703 cells which were injected s c at 2 h postinfection was observed to be prevented in 2 groups with given MOI 25 and 50. The tumor growth of MOI 10 group occurred at a lower exponential rate than that of control,after a 20 d latent period. It was evident that parvovirus H-1 exhibited a direct inhibitory effect on the formation and growth of human hepatoma cells in vivo as well as in vitro.

Inhibitory Effect of Green Tea Extract on the Carcinogenesis Induced by Asbestos Plus Benzo(a)pyrene in Rat

In this experiment lung carcinoma was induced by crocidolite plus benzo(a)pyrene in rat. From the cancer models, we observcd that the incidcnce (16.0%) of lung carcinomas was lowel, and the survival time (376 days) of the first case of carcinoma and the mean survival time (758 days) of the rats with carcinoma were higher in the group of rats drinking 2% green tea extract for life than in the positive group (without drinking green tea extract). The mortality ratio (0.5047) was smaller in the cxperimental group than in the positive control group, and the survival curve of the experimental group significantly raised up, in comparison with the positive group.

Inhibitory effect of tenomodulin versus ranibizumab on in vitro angiogenesis

AIM： To evaluate anti-angiogenic effect of tenomodulin （TNMD） and ranibizumab on cell proliferation and capillary- like morphogenesis of vascular endothelial cells under the stimulation of vascular endothelial growth factor （VEGF） in vitro. METHODS： The effects of TNMD and ranibizumab on VEGF-induced proliferation of human umbilical vein endothelial cells （HUVECs） were evaluated by MTT assay, and the effects of TNMD and ranibizumab on capillary- like structures formed by HUVECs under the stimulation of VEGF were examined in culture. Capillary-like morphogenesis of HUVECs was quantitatively evaluated, and total lengths of tube-like structures per field were measured in a masked way. RESULTS： HUVECs with both ranibizumab and TNMD protein showed MTT reduction in VEGF-stimulated cell proliferation as expected, while MTT absorbance in the HUVECs with TNMD was significantly declined than that with ranibizumab （P〈O.01）. The capillary-like structures formed by HUVECs were markedly impaired by the presence of both TNMD and ranibizumab in the culture medium. The total length of the capillary-like structures per field was significantly shorter in the medium with TNMD than that of ranibizumab （P〈0.01）. The inhibitory effect of TNMD on tube formation in vitro angiogenesis was significantly stronger than that of ranibizumab. CONCLUSION： TNMD may have stronger inhibitory effect than ranibizumab on in vitro angiogenesis.

Preparation and Inhibitory Effects of 20(S)-Ginsenoside Rh_2 on Hep-A-22 Cells

A modified method of preparing 20（S）-ginsenoside Rh2（G-Rh2） and the inhibitory effect of 20（S）-ginsenoside Rh2 on Hep-A-22 cells were investigated. The total saponins and strong alkali were dissolved in glycerol at the atmospheric pressure, and the degradation was performed at a high temperature. After G-Rh2 had been isolated and purified, MTT（methyl thiazolyl tetrazolium） assay was applied to evaluating the effect of 20（S）-ginsenoside Rh2 on the cells viability and morphological changes were observed. It was shown that 20（S）-ginsenoside Rh2 can reduce Hep-A-22 cells viability in dose-dependent manner and the cells took on cell shrinkage, membrane blebbing, chromosomal condensations, especially under the higher concentrations of it. In conclusion, 20（S）-ginsenoside Rh2 can be prepared effectively that not only decreases viability but also induces the apoptosis of Hep-A-22 cells.

INHIBITORY EFFECT OF GLYCYRRHIZA URALENSIS FISH AND CHELIDONIUM MAJUS L ON GASTROCARCINOGENESIS . INDUCED BY N-METHYL-N' -NITRO-N-NITROSOGUANIDINE

In order to investigate the antagonistic effect of Glycyrrhlza Uralensis Fish (GUF) and Chelidonium maJus L (CML) on gastrccarcinogenesls Induced by MNNG in Wastar rats, we treated the rats with MNNG alone (group 1) and with MNNG plus GUF and CML (group 2 and 3) respectively. The Incidence of Infiltrating adenocarcinoma of the glandular stomach and duodenum in group 2 was significantly lower than that in group 1 (26.7% vs. 67.8%). The differentiation and aggresslvenees of carcinomas occured in group 2 were much better and mild than those in group 1. Present study also demonstrated that the Inhibitory effect of CML on proliferation of human stomach carcinoma cell line MGC-803 was very remarkable; in addition, GUF and CML were able to antagonise the mutagenlc activation of MNNG. These results suggest that GUF and CML may be empoyed In prevention of gastric carcinoma.

Inhibitory Effects of Commonly Used Fungicides against Cercospora arachidicola Hori

Early leaf spot is an important disease of peanut, seriously affecting the yield of peanut. The inhibitory effects of different pesticides against early leaf spot have not been analyzed systematically. Based on screening of Cercospora arachidicola Hori in earlier period, the inhibition rates of different pesticides on C. arachidicola growth were studied, and pesticides with strong inhibitory effects against C. arachidicola were screened. The paper provided a reference for field imitation test.

Inhibitory Effect of Garlic, Clove and Carrot on Growth of Aspergillus Flavus and Aflatoxin Production

The inhibitory effeet of crude extracts of garlic, clove and carrot at concentrations of 20,000, 40,000,60,000, 80,000 and 100,000 μg/mL on growth of Aspergillus and aflatoxin production in rice was investigated. Theresults showed that garlic, clove and carro could inhibit the growth of A. jlavus and aflatoxin production. Garlic and cloveat 100,000 μg/mL. highly reduced the level of anatoxin from 5.94 to 0. 15 and 0.06 μg/g respectively whereas carrot at20,000μg/mL reduced the most level of aflatoxin from 5.94 to 0.03μg/g. Garlic, clove and carrot at 100,000μg/mL also inhibited the mould groWth. The most effective herb for inhibiting the growth of A. flavus and anatoxin production was garlic.

Inhibitory Effect of Extracts from Helianthus tuberosus Leaves against Phytophthora capsici and Pot Verification Test

By growth rate method, the inhibitory effects of five solvent extracts from Helianthus tuberosus leaves against Phytophthora capsici were studied in the test. The results showed that different solvent extracts all had inhibitory effect against P. capsici, while 12.5 mg/mL of extracts from H. tuberosus leaves with petroleum ether and ethyl acetate as solvents had the highest inhibitory effect against P. capsici, reaching 100%. In case of various solvent extracts with different concentration gradients, ethyl acetate extract had the most significant inhibitory effect; when the concentration was 5 mg/mL, the inhibitory effect of ethyl acetate extract had reached 100% ; when the concentration reduced to 2.5 mg/mL, the inhibitory effect was still （27.91 ±2. 076） %, significantly higher than that of other solvent extracts at the same concentration. The 50 times dilution of ethyl acetate extract from H. tuberosus leaves was selected for pot test against pepper blight. , and the results showed that its control effect against pepper blight reached 100.00%, superior than that of chemical agent 25% metalaxyl WP 400 times dilution.

Inhibitory effect of cyclosporin A on the immunological rejection of rats with cerebral hemorrhage following transplantation of nerve growth factors transfected glial cells

BACKGROUND： At present, it has been confirmed that immunological rejection exists in the cell transplantation in brain tissue, the effects of immunosuppressant on the immunological rejection and the survival of grafts in brain cell transplantation are worthy being investigated further. OBJECTIVE： To observe the immunological rejection after transgeneic cell transplantation in treating cerebra hemorrhage in rats, and investigate the interventional effect of cyclosprin. DESIGN ： A randomized controlled study SETTINGS： Second Affiliated Hospital of Xuzhou Medical College; First Affiliated Hospital of Nanjing Medica University. MATERIALS： Thirty-five healthy clean-degree SD rats of 6-8 weeks old were used, weighing 200-250 g, either male or female; The FACSort flow cytometer （American BD Company） and NYD-1000 image analytical system were used, The rat-anti-rat CD4 monoclonal antibody, rat-anti-rat CD8 monoclonal antibody, and rat-anti-rat MHC Ⅱ antigen monoclonal antibody were purchased from Santa Cruz Company; SP and DAB kits were purchased from Beijing Zhongshan Bio-engineering Company. XSP-8C2 light microscope was the product of Shanghai Zousun Optical Instrument, Co.,Ltd, and KYKY-3800B electron microscope was the product of China KYKY Technology Development Co.,Ltd. METHODS ： The experiments were carried out in the animal experimental center of Nanjing Medical University from April to July in 2003. ① Model establishment： The rats were anesthetized, and then the coordinates of left internal capsule were identified, and the needle was withdrawn after 120 μL blood was injected into the internal capsule. Adenoviruses were taken as the carriers, after the astrocytes were successfully transfected by nerve growth factor（NGF） gene, 0.2 mL cell suspension was injected into the sites of cerebral hemorrhage. Thirty successfully established rat models were randomly divided into cyclosporin A group （n=18） and control group, the rats were treated with intraperitoneal injection of cyclosporin A （10 mg/kg per day） intraperitoneal injection of saline of the same dosage from the 1^st day after transplantation, once a day for 7 days continuously.② CD4^＋ and CD4^＋ detection： The CD4^＋ and CD4^＋ T lymphocytes in caudal vein were counted with flow cytometer at 15 days after treatment. ③ Morphological observation in the transplanted sites： The rats were killed and then brain tissues were taken out, the transplanted sites and the structure of the normal brain tissue around the transplanted sites were observed with light and electron microscopes. ④Detections of the infiltration of T lymphocyte subsets and expression of major histocompatibility complex （MHC） Ⅱ antigen in the transplanted sites： The image analysis of immunohistochemical sections was performed with the image analytical system, and the integral optical density （IOD） was taken as the statistical value to observe the infiltration of T lymphocyte subsets and expression of MHC Ⅱ antigen in the transplanted sites, and the normal brain tissue around the transplanted sites were taken as controls. MATN OUTCOME MEASURES： ① Countings of CD4^＋ and CD4^＋ in peripheral blood; ②Results of the morphological observation in the transplanted sites; ③ Infiltration of T lymphocyte subsets and expression of MHC Ⅱ antigen in the transplanted sites RESULTS ： Totally 35 rats were used, and 30 were successfully made into models, 5 died during the treatment, the other 25 were involved in the analysis of results. ① Results of CD4^＋ and CD4^＋ T lymphocytes in pedpherel blood： The percentages of CD4^＋ and CD4^＋ T lymphocytes in the cyclosporin A group were （29.20±3.97）% and （20.65±2,02）%, respectively, which were obviously lower than those in the control group [（47,39±3,01）%, （28.30±2.36）%, t=-4.983, 4.012, P 〈 0.05], and the CDC/CD4^＋ ratio was obviously lower than that in the control group （1,41±0.86, 1,64^＋0.69, t=-3. 871, P〈 0.05）.② Morphological results in the transplanted sites： Under optical and electron microscopes, the survival region of the transplant was round, and it had an unobvious migration region with the normal brain tissues, the grafts had normal cellular form. Infiltrations of lymphocytes and monocytes were observed in both groups, and mainly located in the transplanted sites, and the expression of lymphocytes in the cyclosporin A group was markedly lower than that in the control group, and no above-mentioned changes were observed in the normal brain tissue around the transplanted sites. ③ Results of CD. and CD4^＋ T lymphocytes and expression of MHC Ⅱ antigen in the transplanted sites： The CD4^＋ and CD4^＋ T lymphocytes and expression of MHC Ⅱ antigen in the transplanted sites were observed in both groups. The IOD of CD4^＋ and CD4^＋ antigen positive cells in the cyclosporin A group were obviously lower than those in the control group （1.85±0.38, 1.44^＋0.33; 3.33±0.37, 2.648±0.56, /=-4.122, 4.434, P〈 0.05）, and the IOD of MHC Ⅱantigen positive cells was markedly lower than that in the control group （0.76±0.22, 0.94±0.24, t=3.885, P 〈 0.05）. CONCLUSION： There is immunological rejection in brain tissue after the transplantation of NSC transgeneic glial cells. ② The immunosuppressant of cyclosporin A can reduce the immunological rejection after the cell transplantation.

COMPARATIVE STUDY ON THE INHIBITORY EFFECT OF GREEN TEA, COFFEE AND LEVAMISOLE ON THE HEPATOCARCINOGENIC ACTION OF DIETHYLNITROSAMINE

The present study aimed at clarifying whether Chinese green tea, coffee and levamisole (LMS) have similar Inhibitory effect on hepatocarclnogenesis induced by diethylnltrosamine (DEN) as they had been proved in our previous aflatoxin B1 (AFB1) experiments. Male Wistar rates were divided into control (A), green tea (B), coffee (C) and levamisole (D) groups. All rats received the same basic DEN treatment according to the program originally designed by Solt and Farber. During the two weeks before and one week after i. p. injection of DEN, the group B, C and D were given 2. 5% green tea, 5% coffee and 0. 1% LMS diet, respectively. The results demonstrated that coffee, LMS and , in particular,green tea showed Inhibitory effect against DEN-induced hepatocarcinogenesis, indicating that green tea can be used as chemopreventive agent for DEN-, as well as for AFB1-induced hepatocarcinogenesis.