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.

Effects of Algae in Tufa Landscapes of Huanglong Scenic Area

Algae play a crucial role in the evolution of earth and life on earth,and also the cycle of matter.With its unique physiological and ecological properties and strong reproductive capacity,algae deeply influence the formation and development of karst.During the formation of tufa landscapes in Huanglong Scenic Area,the coloration,precipitation and corrosion of algae acting on tufa always concordantly exist.The algae living in water add gay colors to the tufa landscapes.The carbonate precipitation facilitated by algae is an important biological cause of the formation of tufa.As the external environmental conditions change,for instance,the shortage of karst water in tufa landscapes,the coloration and powerful corrosion of algae will stand out,which will badly affect the development and visual value of tufa landscapes.By studying the functions of algae in the tufa landscapes of Huanglong Scenic Area,this research was to provide scientific basis for the future study and protection of tufa landscapes.

Mutual effects of nitric oxide and iron on the growth of marine algae

Experiments on the effects of nitric oxide （NO） and iron on the growth of marine microalgae Skeletonema costatum were conducted. The results are as follows： exogenous NO could increase the growth rate of marine algae and raise the biomass remarkably under iron-deficient conditions. But it was a complicated process that the phytoplankton growth was influenced by NO and iron, which was controlled by the NO concentration, the nutrition level of the culture medium and the iron concentration, etc. Meanwhile, the iron concentration in the medium also has a direct influence on the growth and NO release capacity of the algae. Therefore, the effects of NO and iron on the growth of marine phytoplankton were mutual.

Inhibitory effect of Houttuynia cordata Thunb on LPS-induced retinal microglial activation

AIM: To identify the effect of Houttuynia cordata Thunb(HCT) on lipopolysaccharide(LPS)-induced microglial activation and investigate its possible molecular mechanisms. METHODS: The primary retinal microglial cells were cultured from the retinas of newborn Sprague-Dawley rats and exposed to LPS, and/or HCT with different concentrations. The survival ability of retinal microglia cells was tested by standard MTT method. BrdU cell proliferation assay was used to evaluate the proliferation of retinal microglia. Inflammatory factors in the culture supernatants, including TNF-α, iNOS and IL-1β, were measured using ELISA. Microglia cells’ migration was determined with Transwell migration assay. The total p38-MAPK and phosphorylation of p38-MAPK(p-p38-MAPK) were detected with Western blot.RESULTS: Primary retinal microglia in culture exposed to LPS to induce microglia activation. Pretreatment with HCT significantly inhibited the LPS-induced cell proliferation, but not the cell viability. LPS induced inflammatory reaction in microglia and cell migration. HCT significantly reduced LPS-stimulated release of pro-inflammatory factors and decreased the number of migrating cells substantially in a concentration-dependent manner. Moreover, the protein levels of p-p38 MAPK were identified as the up regulation and co-treatment with HCT obviously inhibited the upregulation of p-p38 MAPK, but had no effect on the levels of total p38-MAPK.CONCLUSION: The data suggest that HCT inhibits LPSinduced retinal microglial activation via suppression of the p-p38-MAPK. HCT may be used for the treatment of ocular diseases characterized by over-activated microglia.

The research on the adsorption effect on metal ions by immobilized marine algae

The process of adsorption of Cu^2+ Cd^2+ by immobilized marine algae was investigated, it can be noted from the results that, the process for biosorption of heavy metals (copper, cadmium) by immobilized Laminaria japonica can be described by the Banerm model. According to the model, the adsorption rate constant calculated was 0.107 8 and 0.030 28 min^-1 for Cu^2+ and Cd^2+ respectively. The experimental biosorption equilibrium data for Cu^2+ and Cd^2+ were in good agreement with those calculated by the Langmuir model. The maximum uptake capacity calculated was 83.3 and 112.4 mg/g for Cu^2+ and Cd^2+ according to the Langmuir model, respectively. The appetency of Laminaria japonica to Cu^2+ was better than Cd^2+.

Anaerobic biodegradability of terephthalic acid and its inhibitory effect on anaerobic digestion

The behavior of terephthalic acid (TPA) in anaerobic system has been studied bysemicontinuous bioassays under mesophilic condition with artificial TPA production wastewater. Theeffect of different loading rate of TPA on anaerobic digestion was studied under certain CODloading rate. The results showed that the TPA could be degraded anaerobically within a relativelylow range. The degradable concentration of TPA was less than 500 mg/L in the digester, higherconcentration of TPA could not be degraded totally and the rate of degradation might decrease withthe increase of feed amount. The inhibition is related to both loading rate and accumulatedconcentration of TPA in the digesters.

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.

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.

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.

Interaction mechanism of egg white-derived ACE inhibitory peptide TNGIIR with ACE and its effect on the expression of ACE and AT1 receptor

The egg white-derived hexapeptide TNGIIR inhibits angiotensin-converting enzyme(ACE)activity in vitro.In this work,molecular docking revealed that TNGIIR established hydrogen bonds with the S1(Ala 354),S2(Gln 281,His 513,Tyr 520 and Lys 511)and S1(Glu 162)pockets of ACE.In addition,the potential antihypertensive effect of the oral administration of TNGIIR in spontaneously hypertensive rats(SHR)was investigated,as was the effect of this peptide on the mRNA expression of ACE and angiotensin type 1(AT1)and type 2(AT2)receptors in renal tissue.The oral administration of TNGIIR(2,10 and 50 mg/kg)for up to four weeks did not reduce the blood pressure of SHR,in contrast to captopril(10 mg/kg,orally),but attenuated the mRNA expression of ACE and AT1 receptor(as did captopril).In contrast,both TNGIIR and captopril enhanced the expression of AT2 receptor mRNA.There was no change in the circulating concentration of angiotensin I,but a slight decrease(about 10%)was seen in the concentration of circulating angiotensin II with TNGIIR and captopril.

Dynamic Analysis of an Algae-Fish Harvested Model with Allee Effect

In this paper, an algae-fish harvested model with Allee effect was established to further explore the dynamic evolution mechanism under the influence of key factors. Mathematical theoretical work not only investigated the existence and stability of all possible equilibrium points, but also probed into the occurrence of transcritical and Hopf bifurcation. The numerical simulation works verified the effectiveness of the theoretical derivation results and displayed rich bifurcation dynamical behaviors, which showed that Allee effect and harvest have played a vital role in the dynamic relationship between algae and fish. In summary, it was expected that these research results would be beneficial for promoting the study of bifurcation dynamics in aquatic ecosystems.

Toxic Effects of Phthalates on Ocean Algae

This article discusses the interaction of phthalates and ocean algae based on the standard appraisal method of chemical medicine for algae toxicity. Through the experiments on the toxic effects of dimethyl (o-) phthalate (DMP), diethyl (o-) phthalate (DEP), dibutyl (o-) phthalate (DBP) on ocean algae, the 50 % lethal concentration of the three substances in 48 h and 96 h for plaeodectylum tricornutum, platymonas sp, isochrysis galbana, and skeletonema costatum is obtained. Tolerance limits of the above ocean algae of DMP, DEP, and DBP are discussed.

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.

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 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.

The inhibitory effect of lead on the seedling growth and the induced formation of oxidase isozymes in higher plant

The inhibitory effect of lead on the seed germination and seedling growth was obvi-ously seen in barley,sorghum and wheat.Their differential reactions on the lead solution werefound under the lead stress during the seed germination and seedling growth stages.Wheat ismore sensitive to lead than the other three plants.This can be used to select new crops which canresist lead damage.The changes of the peroxidase and polyphenol oxidase isozymes have beenfound in individual plants which was injured by a lead solution at the seedling and root develop-ment stages.The authors suggest that these isozymes,which have been changed in patterns andnumbers,may be adaptive isozymes.Adaptive isozymes are produced in plant tissue when plantsare in harmful environmental conditions.The change in environmental conditions influences theexpression of the gene which encode peroxidase,polyphenol oxidase isozymes,and promote forma-tion of the adaptive isozymes.

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.

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.