Minimum inhibitory (MIC) and minimum microbicidal concentration (MMC) of polihexanide and triclosan against antibiotic sensitive and resistant Staphylococcus aureus and Escherichia coli strains

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Assadian, Ojan; Wehse, Katrin; Hübner, Nils-Olaf; Koburger, Torsten; Bagel, Simone; Jethon, Frank; Kramer, Axel

2011-01-01

Background: An in-vitro study was conducted investigating the antimicrobial efficacy of polihexanide and triclosan against clinical isolates and reference laboratory strains of Staphylococcus aureus and Escherichia coli. Methods: The minimal inhibitory concentration (MIC) and the minimal microbicidal concentration (MMC) were determined following DIN 58940-81 using a micro-dilution assay and a quantitative suspension test following EN 1040. Polihexanide was tested in polyethylene glycol 4000, triclosan in aqueous solutions. Results: Against all tested strains the MIC of polihexanide ranged between 1–2 µg/mL. For triclosan the MICs varied depending on strains ranging between 0.5 µg/mL for the reference strains and 64 µg/mL for two clinical isolates. A logRF >5 without and logRF >3 with 0.2% albumin burden was achieved at 0.6 µg/mL triclosan. One exception was S. aureus strain H-5-24, where a triclosan concentration of 0.6 µg/mL required 1 minute without and 10 minutes with albumin burden to achieve the same logRFs. Polihexanide achieved a logRF >5 without and logRF >3 with albumin burden at a concentration of 0.6 µg/mL within 30 sec. The exception was the North-German epidemic MRSA strain, were an application time of 5 minutes was required. Conclusion: The clinical isolates of E. coli generally showed higher MICs against triclosan, both in the micro-dilution assay as well in the quantitative suspension test than comparable reference laboratory strains. For polihexanide and triclosan strain dependant susceptibility was shown. However, both antimicrobial compounds are effective when used in concentrations common in practice. PMID:22242087

Sub-inhibitory concentrations of heavy metals facilitate the horizontal transfer of plasmid-mediated antibiotic resistance genes in water environment.

Science.gov (United States)

Zhang, Ye; Gu, April Z; Cen, Tianyu; Li, Xiangyang; He, Miao; Li, Dan; Chen, Jianmin

2018-06-01

Although widespread antibiotic resistance has been mostly attributed to the selective pressure generated by overuse and misuse of antibiotics, recent growing evidence suggests that chemicals other than antibiotics, such as certain metals, can also select and stimulate antibiotic resistance via both co-resistance and cross-resistance mechanisms. For instance, tetL, merE, and oprD genes are resistant to both antibiotics and metals. However, the potential de novo resistance induced by heavy metals at environmentally-relevant low concentrations (much below theminimum inhibitory concentrations [MICs], also referred as sub-inhibitory) has hardly been explored. This study investigated and revealed that heavy metals, namely Cu(II), Ag(I), Cr(VI), and Zn(II), at environmentally-relevant and sub-inhibitory concentrations, promoted conjugative transfer of antibiotic resistance genes (ARGs) between E. coli strains. The mechanisms of this phenomenon were further explored, which involved intracellular reactive oxygen species (ROS) formation, SOS response, increased cell membrane permeability, and altered expression of conjugation-relevant genes. These findings suggest that sub-inhibitory levels of heavy metals that widely present in various environments contribute to the resistance phenomena via facilitating horizontal transfer of ARGs. This study provides evidence from multiple aspects implicating the ecological effect of low levels of heavy metals on antibiotic resistance dissemination and highlights the urgency of strengthening efficacious policy and technology to control metal pollutants in the environments. Copyright © 2018 Elsevier Ltd. All rights reserved.

Fungal growth inhibitory properties of new phytosphingolipid analogues.

Science.gov (United States)

Mormeneo, D; Manresa, A; Casas, J; Llebaria, A; Delgado, A

2008-04-01

To study the growth inhibitory properties of a series of phytosphingosine (PHS) and phytoceramide (PHC) analogues. A panel of two yeast (Candida albicans and Saccharomyces cerevisiae) and six moulds (Aspergillus repens, Aspergillus niger, Penicillium chrysogenum, Cladosporium cladosporioides, Arthroderma uncinatum and Penicillium funiculosum) has been used in this study. A series of new PHS and PHC analogues differing at the sphingoid backbone and the functional group at C1 position were synthesized. Among PHS analogues, 1-azido derivative 1c, bearing the natural D-ribo stereochemistry, showed a promising growth inhibitory profile. Among PHC analogues, compound 12, with a bulky N-pivaloyl group and a Z double bond at C3 position of the sphingoid chain, was the most active growth inhibitor. Minimal inhibitory concentration values were in the range of 23-48 micromol l(-1) for 1c and 44-87 micromol l(-1) for 12. Only scattered data on the antifungal activity of phytosphingolipids have been reported in the literature. This is the first time that a series of analogues of this kind are tested and compared to discern their structural requirements for antifungal activity.

The effect of sub-minimum inhibitory concentration of ciprofloxacin concentrations on enteroaggregative Escherichia coli and the role of the surface protein dispersin

Energy Technology Data Exchange (ETDEWEB)

Mortensen, Ninell P [ORNL; Fowlkes, Jason Davidson [ORNL; Trevino-Dopatka, Sonia [ORNL; Maggart, Michael J [ORNL; Boisen, Nadia [University of Virginia School of Medicine; Doktycz, Mitchel John [ORNL; Nataro, James [University of Virginia School of Medicine; Allison, David P [ORNL

2011-01-01

Enteroaggregative Escherichia coli (EAEC) are bacterial pathogens that cause watery diarrhea, which is often persistent and can be inflammatory. The antibiotic ciprofloxacin is used to treat EAEC infections, but a full understanding of the antimicrobial effects of ciprofloxacin is needed for more efficient treatment of bacterial infections. In this study, it was found that sub-minimum inhibitory concentrations (sub-MICs) of ciprofloxacin had an inhibitory effect on EAEC adhesion to glass and mammalian HEp-2 cells. It was also observed that bacterial surface properties play an important role in bacterial sensitivity to ciprofloxacin. In an EAEC mutant strain where the hydrophobic positively charged surface protein dispersin was absent, sensitivity to ciprofloxacin was reduced compared with the wild-type strain. Identified here are several antimicrobial effects of ciprofloxacin at sub-MIC concentrations indicating that bacterial surface hydrophobicity affects the response to ciprofloxacin. Investigating the effects of sub-MIC doses of antibiotics on targeted bacteria could help to further our understanding of bacterial pathogenicity and elucidate future antibiotic treatment modalities.

Chemical Composition and Enzymes Inhibitory, Brine Shrimp Larvae Toxicity, Antimicrobial and Antioxidant Activities of Caloplaca biatorina

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Tahereh Valadbeigi

2016-10-01

Full Text Available Background This study evaluated the brine shrimp larvae toxicity and enzymes inhibitory especially anti-diabetic potential of Caloplaca biatorina via in vitro inhibition of α-amylase and α-glucosidase using the methanol extracts. Also aldehyde oxidase and xanthine oxidase enzymes inhibitory, cytotoxicity, and antioxidant activities of the species were determined. Methods In this experimental study, different concentrations of the extracts (0.2, 5.0, 1 and 1.5 mg/mL were incubated with enzyme substrate solution and the percentage of enzyme inhibitory activity and IC50 was calculated. Folin- Ciocalteu reagent and aluminium chloride colorimetric methods were used to estimate total phenolic and flavonoid content of extracts. The toxicity of the extract was assessed using the brine shrimp lethality bioassay. The minimal inhibitory concentration (MIC and minimum bactericidal concentration (MBC were determined. High-performance liquid chromatography and Thin-layer chromatography analysis were evaluated. The data were analyzed by SPSS V.21 software. Results Parietin, Emodin, 1,8-Dihydroxy-3-(hydroxymethyl-6- methoxy-9.10-anthracenedione and Rhein were identified. The extract showed strong α-glucosidase, aldehyde oxidase and xanthine oxidase inhibitory activities with IC50 value of 17.12, 40.09 and 11.02 µg/mL respectively. Also methanol extract displayed the strongest DPPH radical scavenging and brine shrimp toxicity (IC50 = 91.11 properties. Conclusions The result obtained suggests that the C. biatorina extract can be classified as non-toxic. Also, it revealed the antioxidant and antidiabetic potential of the lichen.

Dosing strategy based on prevailing aminoglycoside minimum inhibitory concentration in India: Evidence and issues

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Balaji Veeraraghavan

2017-01-01

Full Text Available Aminoglycosides are important agents used for treating drug-resistant infections. The current dosing regimen of aminoglycosides does not achieve sufficient serum level concentration for the infected bacterial pathogen interpreted as susceptible based on laboratory testing. Minimum inhibitory concentration was determined for nearly 2000 isolates of Enterobacteriaceae and Pseudomonas aeruginosa by broth microdilution method. Results were interpreted based on CLSI and EUCAST interpretative criteria and the inconsistencies in the susceptibility profile were noted. This study provides insights into the inconsistencies existing in the laboratory interpretation and the corresponding clinical success rates. This urges the need for revising clinical breakpoints for amikacin, to resolve under dosing leading to clinical failure.

Concentração inibitória mínima de oxitetraciclina para isolados de Aeromonas Hydrophila obtidos de diferentes fontes Minimal inhibitory concentration to oxitetracycline in Aeromonas Hydrophila strains isolated from different sources

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Delton José Pereira Júnior

2006-12-01

Full Text Available Objetivou-se com este trabalho determinar a concentração inibitória mínima (MIC de oxitetraciclina para isolados de Aeromonas hydrophila obtidos de pescado, água de cultivo de peixes e casos de septicemia hemorrágica em peixes. Foi determinado MIC de 100 isolados de A. hydrophila, oriundos de 12 pisciculturas localizadas nos Estados de Minas Gerais, Rio de Janeiro e Rio Grande do Sul, utilizando a técnica de macrodiluição em caldo. Os resultados demonstraram que 14 isolados apresentaram MIC>100 µg/mL (resistentes e 86 apresentaram MICThe aim of this paper was to determine the minimal inhibitory concentration (MIC to oxitetracycline in Aeromonas hydrophila strains isolated from marketed fish, pond water of piscicultures and fish suffering hemorrhagic septicemia. These strains were obtained from 12 different piscicultures from Minas Gerais, Rio de Janeiro e Rio Grande do Sul states. It was determined the MIC to 100 strains, using the broth macrodilution method, and the results showed that 86 strains shown value of MIC100µg/mL (classified as resistant. No differences were observed among strains isolated from marketed fish, pond water and disease outbreaks. I was concluded that the variation detected may represent a risk of selection of resistant bacterial strains in aquatic environments under use of oxitetracycline.

Short-Term Pretreatment of Sub-Inhibitory Concentrations of Gentamycin Inhibits the Swarming Motility of Escherichia Coli by Down-Regulating the Succinate Dehydrogenase Gene

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Yijing Zhuang

2016-09-01

Full Text Available Background/Aims: Motility is a feature of many pathogens that contributes to the migration and dispersion of the infectious agent. Whether gentamycin has a post-antibiotic effect (PAE on the swarming and swimming motility of Escherichia coli (E. coli remains unknown. In this study, we aimed to examine whether short-term pretreatment of sub-inhibitory concentrations of gentamycin alter motility of E. coli and the mechanisms involved therein. Methods: After exposure to sub-inhibitory concentrations (0.8 μg/ml of gentamicin, the swarming and swimming motility of E. coli was tested in semi-solid media. Real-time PCR was used to detect the gene expression of succinate dehydrogenase (SDH. The production of SDH and fumarate by E. coli pretreated with or without gentamycin was measured. Fumarate was added to swarming agar to determine whether fumarate could restore the swarming motility of E. coli. Results: After pretreatment of E. coli with sub-inhibitory concentrations of gentamycin, swarming motility was repressed in the absence of growth inhibition. The expression of all four subunits of SDH was down-regulated, and the intracellular concentration of SDH and fumarate, produced by E. coli, were both decreased. Supplementary fumarate could restore the swarming motility inhibited by gentamycin. A selective inhibitor of SDH (propanedioic acid could strongly repress the swarming motility. Conclusion: Sub-inhibitory concentrations of gentamycin inhibits the swarming motility of E. coli. This effect is mediated by a reduction in cellular fumarate caused by down-regulation of SDH. Gentamycin may be advantageous for treatment of E. coli infections.

Inhibitory effect of extracellular purine nucleotide and nucleoside concentrations on T cell proliferation

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Weiler, Monica [Department of Medicine III and Transfusion Medicine, University Hospital Grosshadern, Ludwig-Maximilians-University, Munich (Germany); Schmetzer, Helga [Helmholtz Center Munich (Germany); German Research Center for Environmental Health, Munich (Germany); Braeu, Marion; Buhmann, Raymund [Helmholtz Center Munich (Germany); German Research Center for Environmental Health, Munich (Germany); Department of Medicine III and Transfusion Medicine, University Hospital Grosshadern, Ludwig-Maximilians-University, Munich (Germany)

2016-11-15

The release of nucleic acids and derivatives after tissue-injury may affect cellular immune-response. We studied the impact of extracellular ribo-, desoxyribonucleotides and nucleosides on T-cell immunity. Peripheral-blood-mononuclear-cells (PBMCs) or isolated CD3{sup +}T-cells obtained from 6 healthy donors were stimulated via CD3/CD28 Dynabeads or dendritic cells (DCs) in the presence or absence of pyrimidine-, purine-nucleotides and -nucleosides (range 2–200 µM). Addition of deoxy-, guanosine-triphosphate (dGTP, GTP) and guanosine resulted concentration dependent in a complete, adenosine-triphosphate (ATP) in a partial inhibition of the induced T-cell-proliferation. Deoxyadenosine-triphosphate (dATP), adenosine and the pyrimidine-ribo- and -deoxyribonucleotides displayed no inhibitory capacity. Inhibitory effects of dGTP and GTP, but not of guanosine and ATP were culture-media-dependent and could be almost abrogated by use of the serum-free lymphocyte-culture-media X-Vivo15 instead of RPMI1640 with standard-supplementation. In contrast to RPMI1640, X-Vivo15 resulted in a significant down-regulation of the cell-surface-located ectonucleotidases CD39 (Ecto-Apyrase) and CD73 (Ecto-5′-Nucleotidase), critical for the extracellular nucleotides-hydrolysis to nucleosides, explaining the loss of inhibition mediated by dGTP and GTP, but not Guanosine. In line with previous findings ATP was found to exert immunosuppressive effects on T-cell-proliferation. Purine-nucleotides, dGTP and GTP displayed a higher inhibitory capacity, but seem to be strictly dependent on the microenvironmental conditions modulating the responsiveness of the respective T-lymphocytes. Further evaluation of experimental and respective clinical settings should anticipate these findings.

Inhibitory effect of extracellular purine nucleotide and nucleoside concentrations on T cell proliferation

International Nuclear Information System (INIS)

Weiler, Monica; Schmetzer, Helga; Braeu, Marion; Buhmann, Raymund

2016-01-01

The release of nucleic acids and derivatives after tissue-injury may affect cellular immune-response. We studied the impact of extracellular ribo-, desoxyribonucleotides and nucleosides on T-cell immunity. Peripheral-blood-mononuclear-cells (PBMCs) or isolated CD3 + T-cells obtained from 6 healthy donors were stimulated via CD3/CD28 Dynabeads or dendritic cells (DCs) in the presence or absence of pyrimidine-, purine-nucleotides and -nucleosides (range 2–200 µM). Addition of deoxy-, guanosine-triphosphate (dGTP, GTP) and guanosine resulted concentration dependent in a complete, adenosine-triphosphate (ATP) in a partial inhibition of the induced T-cell-proliferation. Deoxyadenosine-triphosphate (dATP), adenosine and the pyrimidine-ribo- and -deoxyribonucleotides displayed no inhibitory capacity. Inhibitory effects of dGTP and GTP, but not of guanosine and ATP were culture-media-dependent and could be almost abrogated by use of the serum-free lymphocyte-culture-media X-Vivo15 instead of RPMI1640 with standard-supplementation. In contrast to RPMI1640, X-Vivo15 resulted in a significant down-regulation of the cell-surface-located ectonucleotidases CD39 (Ecto-Apyrase) and CD73 (Ecto-5′-Nucleotidase), critical for the extracellular nucleotides-hydrolysis to nucleosides, explaining the loss of inhibition mediated by dGTP and GTP, but not Guanosine. In line with previous findings ATP was found to exert immunosuppressive effects on T-cell-proliferation. Purine-nucleotides, dGTP and GTP displayed a higher inhibitory capacity, but seem to be strictly dependent on the microenvironmental conditions modulating the responsiveness of the respective T-lymphocytes. Further evaluation of experimental and respective clinical settings should anticipate these findings.

Determination of minumun inhibitory concentration (MIC of Hygromycin B and it’s use like selective agent in Mycosphaerella fijiensis transformation

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Mileidy Cruz-Martín

2001-04-01

Full Text Available The Black sigatoka can be considered from the economic point of view the most serious disease in the gender Musa. At present the use of new biotechnological techniques applied to the study of the host-pathogen interation is glimpsed as an important tool in the future improvement of the commercial cultivars of the banana and plantain. In this study, we tested diferents concentration of Hygromycin B against an isolate of M. fijiensis (CCIBP-1 by the agar dilution method. It was proved that Hygromycin B was able to inhibit the growth of the M. fijiensis starting from 0.5 mg.l-1. This value was taken as the minimum inhibitory concentration, that’s why it could be used like selective agent in the transformation studies of Mycosphaerella complex. By another hands it was demostrated the value of the previous protocol of the Minimum Inhibitory concentration for making evaluations of different fungus pathogens against antimicribial substance. Key words: antibiotic, Black sigatoka, phytopathogen

Inhibitory effects of antimicrobial agents against Fusarium species.

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Kawakami, Hideaki; Inuzuka, Hiroko; Hori, Nobuhide; Takahashi, Nobumichi; Ishida, Kyoko; Mochizuki, Kiyofumi; Ohkusu, Kiyofumi; Muraosa, Yasunori; Watanabe, Akira; Kamei, Katsuhiko

2015-08-01

We investigated the inhibitory effects of antibacterial, biocidal, and antifungal agents against Fusarium spp. Seven Fusarium spp: four F. falciforme (Fusarium solani species complex), one Fusarium spp, one Fusarium spp. (Fusarium incarnatum-equiseti species complex), and one F. napiforme (Gibberella fujikuroi species complex), isolated from eyes with fungal keratitis were used in this study. Their susceptibility to antibacterial agents: flomoxef, imipenem, gatifloxacin, levofloxacin, moxifloxacin, gentamicin, tobramycin, and Tobracin® (contained 3,000 μg/ml of tobramycin and 25 μg/ml of benzalkonium chloride (BAK), a biocidal agent: BAK, and antifungal agents: amphotericin B, pimaricin (natamycin), fluconazole, itraconazole, miconazole, voriconazole, and micafungin, was determined by broth microdilution tests. The half-maximal inhibitory concentration (IC50), 100% inhibitory concentration (IC100), and minimum inhibitory concentration (MIC) against the Fusarium isolates were determined. BAK had the highest activity against the Fusarium spp. except for the antifungal agents. Three fluoroquinolones and two aminoglycosides had inhibitory effects against the Fusarium spp. at relatively high concentrations. Tobracin® had a higher inhibitory effect against Fusarium spp. than tobramycin alone. Amphotericin B had the highest inhibitory effect against the Fusarium spp, although it had different degrees of activity against each isolate. Our findings showed that fluoroquinolones, aminoglycosides, and BAK had some degree of inhibitory effect against the seven Fusarium isolates, although these agents had considerably lower effect than amphotericin B. However, the inhibitory effects of amphotericin B against the Fusarium spp. varied for the different isolates. Further studies for more effective medications against Fusarium, such as different combinations of antibacterial, biocidal, and antifungal agents are needed. © The Author 2015. Published by Oxford University Press on

Activity of TDT 067 (terbinafine in Transfersome) against agents of onychomycosis, as determined by minimum inhibitory and fungicidal concentrations.

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Ghannoum, Mahmoud; Isham, Nancy; Herbert, Jacqueline; Henry, William; Yurdakul, Sam

2011-05-01

TDT 067 is a novel carrier-based dosage form (liquid spray) of 15 mg/ml of terbinafine in Transfersome that has been developed to deliver terbinafine to the nail bed to treat onychomycosis. In this study, we report the in vitro activities of TDT 067 against dermatophytes, compared with those of the Transfersome vehicle, naked terbinafine, and commercially available terbinafine (1%) spray. The MICs of TDT 067 and comparators against 25 clinical strains each of Trichophyton rubrum, T. mentagrophytes, and Epidermophyton floccosum were determined according to the CLSI M38-A2 susceptibility method (2008). Minimum fungicidal concentrations (MFCs) were determined by subculturing visibly clear wells from the MIC microtiter plates. TDT 067 demonstrated potent activity against the dermatophyte strains tested, with an MIC range of 0.00003 to 0.015 μg/ml. Overall, TDT 067 MIC(50) values (defined as the lowest concentrations to inhibit 50% of the strains tested) were 8-fold and 60-fold lower than those of naked terbinafine and terbinafine spray, respectively. The Transfersome vehicle showed minimal inhibitory activity. TDT 067 demonstrated lower MFC values for T. rubrum and E. floccosum than naked terbinafine and terbinafine spray. TDT 067 has more potent antifungal activity against dermatophytes that cause nail infection than conventional terbinafine preparations. The Transfersome vehicle appears to potentiate the antifungal activity of terbinafine. Clinical investigation of TDT 067 for the topical treatment of onychomycosis is warranted.

Comparison of in vitro efficacy of linezolid and vancomycin by determining their minimum inhibitory concentrations against methicillin resistant Staphylococcus aureus (MRSA)

International Nuclear Information System (INIS)

Kaleem, F.; Usman, J.; Hassan, A.

2011-01-01

Objectives: To compare the in vitro activities of vancomycin and linezolid against methicillin resistant Staphyloccus aureus in our set up to help in formulating a better empirical treatment and reduce the emergence of vancomycin resistant Staphylococcus aureus. Methods: The study was conducted over a period of 6 months(July 1, 2009 - Dec 1, 2009). Fifty Methicillin resistant Staphylococcus aureus isolated from the clinical isolates of Military Hospital Rawalpindi were subjected to the determination of Minimum inhibitory concentrations of linezolid and vancomycin using E-strips. Results: All the isolated organisms were uniformly susceptible to both the antibiotics. Vancomycin showed higher minimum inhibitory concentrations (MICs) as compared to linezolid MICs. Conclusion: This study suggests that linezolid and vancomycin have similar in vitro efficacy for methicillin resistant Staphyloccus aureus infections. (author)

Influence of pH and lactic acid concentration on Clostridium tyrobutyricum during continuous growth in a pH-auxostat

NARCIS (Netherlands)

Thylin, I; Schuisky, P; Lindgren, S; Gottschal, J.C

1995-01-01

The aim of this project was to establish the minimal inhibitory concentration (MIC) of lactic acid for growth of Clostridium tyrobutyricum. A pH-auxostat was used to maintain a constant pH and to allow continuous growth at the highest possible rates at fixed, but adjustable concentrations of

Resazurin-based 96-well plate microdilution method for the determination of minimum inhibitory concentration of biosurfactants.

Science.gov (United States)

Elshikh, Mohamed; Ahmed, Syed; Funston, Scott; Dunlop, Paul; McGaw, Mark; Marchant, Roger; Banat, Ibrahim M

2016-06-01

To develop and validate a microdilution method for measuring the minimum inhibitory concentration (MIC) of biosurfactants. A standardized microdilution method including resazurin dye has been developed for measuring the MIC of biosurfactants and its validity was established through the replication of tetracycline and gentamicin MIC determination with standard bacterial strains. This new method allows the generation of accurate MIC measurements, whilst overcoming critical issues related to colour and solubility which may interfere with growth measurements for many types of biosurfactant extracts.

[Inhibitory mechanism of ifenprodil tartrate on rabbit platelet aggregation].

Science.gov (United States)

Irino, O; Saitoh, K; Hayashi, T; Ohkubo, K

1985-05-01

The effects of dl-erythro-4-benzyl-alpha-(4-hydroxyphenyl)-beta-methyl-l-piperidine-eth anol tartrate (ifenprodil tartrate) on rabbit platelet aggregation in vitro and ex vivo were studied. Ifenprodil tartrate inhibited platelet aggregation in vitro induced by ADP, collagen and epinephrine. It also inhibited 5-hydroxytryptamine (5-HT) uptake into platelets and 5-HT release from platelets. Since these inhibitory effects of ifenprodil tartrate on the functions of rabbit platelets were similar to the effects of imipramine, the effects of ifenprodil tartrate may be due to the stabilizing action of ifenprodil tartrate on the platelet membrane. The platelet aggregation by ADP was significantly inhibited in rabbits after oral administration of ifenprodil tartrate, the maximal plasma level of ifenprodil being reached at 20 ng/ml ex vivo, while the maximal level was only 1/40 of the minimal concentration of ifenprodil tartrate necessary to inhibit platelet aggregation in vitro. These results indicate that factors other than ifenprodil tartrate acting directly on the platelets (e.g., PGI2 which is an endogenous inhibitor of platelet aggregation) are involved in inducing the inhibitory effects of ifenprodil tartrate on platelet aggregation ex vivo. The effects of ifenprodil tartrate on both PGI2 release from the aorta and the inhibitory effects of PGI2 on platelet aggregation in vitro were investigated: PGI2 was found to intensify the inhibitory effects of ifenprodil tartrate on platelet aggregation in vitro, but there was little effect, if any, on PGI2 release. Therefore, it is considered that the ex vivo effects of ifenprodil tartrate might be due to its interaction with endogenous PGI2 in the blood.

Risk factors for and role of OprD protein in increasing minimal inhibitory concentrations of carbapenems in clinical isolates of Pseudomonas aeruginosa.

Science.gov (United States)

Hirabayashi, Aki; Kato, Daizo; Tomita, Yuka; Iguchi, Mitsutaka; Yamada, Keiko; Kouyama, Yuichi; Morioka, Hiroshi; Tetsuka, Nobuyuki; Yagi, Tetsuya

2017-11-01

This study examined the risk factors for, and molecular mechanisms underlying, the increase in carbapenem minimum inhibitory concentrations (MICs) in clinical isolates of Pseudomonas aeruginosa. Consecutive clinical isolates of P. aeruginosa were collected. The MicroScan WalkAway system detected more than fourfold increases in the MICs of carbapenems in P. aeruginosa isolates serially recovered from some patients during their clinical course. The clinical risk factors associated with this increase were examined by multiple logistic regression analysis. Western blot analysis and nucleotide sequencing of the oprD gene of 19 clonally related and paired P. aeruginosa isolates from the same patients were undertaken to examine the mechanisms underlying the increase in MICs. The results showed that prior use of carbapenems (OR, 2.799; 95 % CI, 1.088-7.200; P=0.033) and the use of ventilators or tracheostomies (OR, 2.648; 95 % CI, 1.051-6.671; P=0.039) were risk factors for increased carbapenem MICs. Analysis of the underlying mechanisms revealed that loss of functional OprD protein due to mutation of the oprD gene tended to occur in P. aeruginosa isolates with imipenem MICs of more than 8 µg ml -1 ; a reduction in OprD expression was observed in P. aeruginosa isolates with imipenem MICs of 4 or 8 µg ml -1 . This difference in the resistance mechanism was not correlated with the MICs of meropenem. This difference in the resistance mechanism of P. aeruginosa indicates a critical breakpoint at an imipenem MIC of 8 µg ml -1 , in accordance with EUCAST criteria. Reducing carbapenem use will prevent P. aeruginosa clinical isolates from developing resistance to carbapenems.

Release of Gentamicin and Vancomycin from Preformed Spacers in Infected Total Hip Arthroplasties: Measurement of Concentrations and Inhibitory Activity in Patients’ Drainage Fluids and Serum

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Dario Regis

2013-01-01

Full Text Available Gentamicin (G and vancomycin (V concentrations in drainage fluids obtained from patients during the first 24 hours after implantation of antibiotic-loaded polymethylmethacrylate (PMMA spacers in two-stage revision of infected total hip arthroplasty were studied. The inhibitory activity of drainage fluids against different multiresistant clinical isolates was investigated as well. Seven hips were treated by implantation of industrial G-loaded spacers. Vancomycin was added by manually mixing with PMMA bone cement. Serum and drainage fluid samples were collected 1, 4, and 24 hours after spacer implantation. Antibiotics concentrations and drains bactericidal titer of combination were determined against multiresistant staphylococcal strains. The release of G and V from PMMA cement at the site of infection was prompt and effective. Serum levels were below the limit of detection. The local release kinetics of G and V from PMMA cement was similar, exerting a pronounced, combined inhibitory effect in the implant site. The inhibitory activity of drainage fluids showed substantial intersubject variability related to antibiotic concentrations and differed according to the pathogens tested. Gentamicin and vancomycin were released from temporary hip spacers at bactericidal concentrations, and their use in combination exerted strong inhibition against methicillin-resistant S. aureus and Coagulase Negative Staphylococci strains.

Minimum inhibitory concentration distribution in environmental Legionella spp. isolates.

Science.gov (United States)

Sandalakis, Vassilios; Chochlakis, Dimosthenis; Goniotakis, Ioannis; Tselentis, Yannis; Psaroulaki, Anna

2014-12-01

In Greece standard tests are performed in the watering and cooling systems of hotels' units either as part of the surveillance scheme or following human infection. The purpose of this study was to establish the minimum inhibitory concentration (MIC) distributions of environmental Legionella isolates for six antimicrobials commonly used for the treatment of Legionella infections, by MIC-test methodology. Water samples were collected from 2004 to 2011 from 124 hotels from the four prefectures of Crete (Greece). Sixty-eight (68) Legionella isolates, comprising L. pneumophila serogroups 1, 2, 3, 5, 6, 8, 12, 13, 15, L. anisa, L. rubrilucens, L. maceachernii, L. quinlivanii, L. oakridgensis, and L. taurinensis, were included in the study. MIC-tests were performed on buffered charcoal yeast extract with α-ketoglutarate, L-cysteine, and ferric pyrophosphate. The MICs were read after 2 days of incubation at 36 ± 1 °C at 2.5% CO2. A large distribution in MICs was recorded for each species and each antibiotic tested. Rifampicin proved to be the most potent antibiotic regardless of the Legionella spp.; tetracycline appeared to have the least activity on our environmental isolates. The MIC-test approach is an easy, although not so cost-effective, way to determine MICs in Legionella spp. These data should be kept in mind especially since these Legionella species may cause human disease.

Nanocapsular Dispersion of Cinnamaldehyde for Enhanced Inhibitory Activity against Aflatoxin Production by Aspergillus flavus

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Hongbo Li

2015-04-01

Full Text Available Cinnamaldehyde (CA is marginally soluble in water, making it challenging to evenly disperse it in foods, and resulting in lowered anti-A. flavus efficacy. In the present study, nano-dispersed CA (nano-CA was prepared to increase its aqueous solubility. Free and nano-dispersed CA were compared in terms of their inhibitory activity against fungal growth and aflatoxin production of A. flavus both in Sabouraud Dextrose (SD culture and in peanut butter. Our results indicated that free CA inhibited the mycelia growth and aflatoxin production of A. flavus with a minimal inhibitory concentration (MIC value of 1.0 mM, but promoted the aflatoxin production at some concentrations lower than the MIC. Nano-CA had a lower MIC value of 0.8 mM against A. flavus, and also showed improved activity against aflatoxin production without the promotion at lower dose. The solidity of peanut butter had an adverse impact on the antifungal activity of free CA, whereas nano-dispersed CA showed more than 2-fold improved activity against the growth of A. flavus. Free CA still promoted AFB1 production at the concentration of 0.25 mM, whereas nano-CA showed more efficient inhibition of AFB1 production in the butter.

The Antifungal Inhibitory Concentration Effectiveness Test From Ethanol Seed Arabica Coffee (Coffea arabica) Extract Against The Growth Of Candida albicans Patient Isolate With In Vitro Method

Science.gov (United States)

Satria Rakatama, Adam; Pramono, Andri; Yulianti, Retno

2018-03-01

Candida albicans are the most frequent cause of Vulvovaginalis Candidiasis infection. Its treatment using antifungal drugs, are oftenly caused side effects. The reduction of C.albicans growth and the reduction of antifungal drugs side effect, were our main purposed. Our study objective is determine the effectiveness of inhibitory power of arabica coffee seed ethanol extract on the growth of C.albicans patient isolates. The type of this research is experimental research. Kirby-bauer method with the Saboraud Dextrose Agar (SDA) media was used in this experiment. Inhibitory zone was observed around the disc, to determine the inhibitory power. The results showed that the inhibitory zone was formed on arabica coffee seed ethanol extract on 10%, 20%, 40%, and 80% concentration. Kruskal-Wallis test results (pthe concentration groups tested against the treatment group. The inhibitory zone was formed because of biochemical compound in arabica coffee seed such as caffeine, phenol, alkaloids, flavonoids, and saponins. Inhibitory zone in C.albicans patient isolates were smaller compared with C.albicans ATCC 90028 as gold standard. This showed that the virulence of C.albicans from patients isolates were higher. We concluded that arabica coffee seed ethanol extract could inhibiting the growth of C.albicans patient isolates. Optimization of coffee seed ethanol extract to obtain maximum active ingredients still needs to be done. This knowledge is expected to be used for the beginning manufacturer antifungal drug from natural product.

Inhibitory effects of Caesalpinia sappan on growth and invasion of methicillin-resistant Staphylococcus aureus.

Science.gov (United States)

Kim, Kang-Ju; Yu, Hyeon-Hee; Jeong, Seung-Il; Cha, Jung-Dan; Kim, Shin-Moo; You, Yong-Ouk

2004-03-01

In the present study, we investigated antimicrobial activity of Caesalpinia sappan against clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and effect of Caesalpinia sappan extract on the invasion of MRSA to human mucosal fibroblasts (HMFs). Chloroform, n-butanol, methanol, and aqueous extracts of the Caesalpinia sappan showed antimicrobial activity against standard methicillin-sensitive Staphylococcus aureus (MSSA) as well as MRSA. Methanol extract of Caesalpinia sappan demonstrated a higher inhibitory activity than n-butanol, chloroform, and aqueous extracts. In the checkerboard dilution method, methanol extract of Caesalpinia sappan markedly lowered the minimal inhibitory concentrations (MICs) of ampicillin and oxacillin against MRSA. To determine whether methanol extract of Caesalpinia sappan inhibits the MRSA invasion to HMFs, the cells were treated with various sub-MIC concentrations of methanol extract and bacterial invasion was assayed. MRSA invasion was notably decreased in the presence of 20-80 microg/ml of Caesalpinia sappan extract compared to the control group. The effect of Caesalpinia sappan extract on MRSA invasion appeared dose-dependent. These results suggest that methanol extract of Caesalpinia sappan may have antimicrobial activity and the potential to restore the effectiveness of beta-lactam antibiotics against MRSA, and inhibit the MRSA invasion to HMFs.

Effects of sub-minimum inhibitory concentrations of ciprofloxacin on enteroaggregative Escherichia coli and the role of the surface protein dispersin

Energy Technology Data Exchange (ETDEWEB)

Fowlkes, Jason Davidson [ORNL; Doktycz, Mitchel John [ORNL; Allison, David Post [ORNL

2011-01-01

Enteroaggregative Escherichia coli (EAEC) are bacterial pathogens that cause watery diarrhoea, which is often persistent and can be inflammatory. The antibiotic ciprofloxacin is used to treat EAEC infections, but a full understanding of the antimicrobial effects of ciprofloxacin is needed for more efficient treatment of bacterial infections. In this study, it was found that sub-minimum inhibitory concentrations (sub-MICs) of ciprofloxacin had an inhibitory effect on EAEC adhesion to glass and mammalian HEp-2 cells. It was also observed that bacterial surface properties play an important role in bacterial sensitivity to ciprofloxacin. In an EAEC mutant strain where the hydrophobic positively charged surface protein dispersin was absent, sensitivity to ciprofloxacin was reduced compared with the wild-type strain. Identified here are several antimicrobial effects of ciprofloxacin at sub-MIC concentrations indicating that bacterial surface hydrophobicity affects the response to ciprofloxacin. Investigating the effects of sub-MIC doses of antibiotics on targeted bacteria could help to further our understanding of bacterial pathogenicity and elucidate future antibiotic treatment modalities.

Inhibitory concentrations of 2,4D and its possible intermediates in sulfate reducing biofilms

Energy Technology Data Exchange (ETDEWEB)

Garcia-Cruz, Ulises [Department of Biotechnology, Environmental Science and Technology, Universidad Autonoma Metropolitana-Iztapalapa, Ave. San Rafael Atlixco 186, Vicentina, 09340 D.F. (Mexico); Celis, Lourdes B. [Division de Ciencias Ambientales, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la Presa San Jose 2055, Lomas 4a. Seccion, 78216 San Luis Potosi, S.L.P. (Mexico); Poggi, Hector [Department of Biotechnology and Bioengineering, CINVESTAV, Av. Instituto Politecnico Nacional 2508, Col. San Pedro Zacatenco, 07360 D.F. (Mexico); Meraz, Monica, E-mail: meraz@xanum.uam.mx [Department of Biotechnology, Environmental Science and Technology, Universidad Autonoma Metropolitana-Iztapalapa, Ave. San Rafael Atlixco 186, Vicentina, 09340 D.F. (Mexico)

2010-07-15

Different concentrations of the herbicide 2,4-dichlorophenoxyacetic acid (2,4D) and its possible intermediates such as 2,4-dichlorophenol (2,4DCP), 4-chlorophenol (4CP), 2-chlorophenol (2CP) and phenol, were assayed to evaluate the inhibitory effect on sulfate and ethanol utilization in a sulfate reducing biofilm. Increasing concentrations of the chlorophenolic compounds showed an adverse effect on sulfate reduction rate and ethanol conversion to acetate, being the intermediate 2,4DCP most toxic than the herbicide. The monochlorophenol 4CP (600 ppm) caused the complete cessation of sulfate reduction and ethanol conversion. The ratio of the electron acceptor to the electron donor utilized as well as the sulfate utilization volumetric rates, diminished when chlorophenols and phenol concentrations were increased, pointing out to the inhibition of the respiratory process and electrons transfer. The difference found in the IC{sub 50} values obtained was due to the chemical structure complexity of the phenolic compounds, the number of chlorine atoms as much as the chlorine atom position in the phenol ring. The IC{sub 50} values (ppm) indicated that the acute inhibition on the biofilm was caused by 2,4DCP (17.4) followed by 2,4D (29.0), 2CP (99.8), 4CP (108.0) and phenol (143.8).

Minimum inhibitory concentration of vancomycin to methicillin resistant Staphylococcus aureus isolated from different clinical samples at a tertiary care hospital in Nepal

Directory of Open Access Journals (Sweden)

Arjun Ojha Kshetry

2016-07-01

Full Text Available Abstract Background Methicillin resistant Staphylococcus aureus (MRSA has evolved as a serious threat to public health. It has capability to cause infections not only in health care settings but also in community. Due to the multidrug resistance shown by MRSA, there are limited treatment options for the infections caused by this superbug. Vancomycin is used as the drug of choice for the treatment of infections caused by MRSA. Different studies from all around the world have documented the emergence of strains of S. aureus those are intermediate sensitive or resistant to vancomycin. And recently, there have been reports of reduced susceptibility of MRSA to vancomycin, from Nepal also. So the main purpose of this study was to determine the minimum inhibitory concentration (MIC of vancomycin to methicillin resistant S. aureus isolated from different clinical specimens. Methods Total 125 strains of S. aureus isolated from different clinical samples at KIST Medical College and Teaching Hospital, Lalitpur, Nepal from Nov 2012 to June 2013, were subjected to MRSA detection by cefoxitin disc diffusion method. The minimum inhibitory concentrations of vancomycin to confirmed MRSA strains were determined by agar dilution method. Yellow colored colonies in mannitol salt agar, which were gram positive cocci, catalase positive and coagulase positive were confirmed to be S. aureus. Results Among, total 125 S. aureus strains isolated; 47(37.6% were MRSA. Minimum inhibitory concentrations of vancomycin to the strains of MRSA ranged from 0.125 μg/ml to 1 μg/ml. Conclusion From our findings we concluded that the rate of isolation of MRSA among all the strains of S. aureus isolated from clinical samples was very high. However, none of the MRSA strains were found to be vancomycin intermediate-sensitive or vancomycin-resistant.

Cytotoxicity and inhibitory effects of low-concentration triclosan on adipogenic differentiation of human mesenchymal stem cells

Energy Technology Data Exchange (ETDEWEB)

Guo, Li-Wu [Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); Wu, Qiangen [Division of Biochemical Toxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); Green, Bridgett; Nolen, Greg [Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); Shi, Leming [Division of Systems Biology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); LoSurdo, Jessica [Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892 (United States); Deng, Helen [Arkansas Department of Health, Little Rock, AR 72205 (United States); Bauer, Steven [Division of Cellular and Gene Therapies, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892 (United States); Fang, Jia-Long, E-mail: jia-long.fang@fda.hhs.gov [Division of Biochemical Toxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); Ning, Baitang, E-mail: baitang.ning@fda.hhs.gov [Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States)

2012-07-15

Humans at all ages are continually exposed to triclosan (TCS), a widely used antimicrobial agent that can be found in many daily hygiene products, such as toothpastes and shampoos; however, the toxicological and biological effects of TCS in the human body after long-term and low-concentration exposure are far from being well understood. In the current study, we investigated the effects of TCS on the differentiation of human mesenchymal stem cells (hMSCs) by measuring the cytotoxicity, morphological changes, lipid accumulation, and the expression of adipocyte differentiation biomarkers during 21-day adipogenesis. Significant cytotoxicity was observed in un-induced hMSCs treated with high-concentration TCS (≥ 5.0 μM TCS), but not with low-concentration treatments (≤ 2.5 μM TCS). TCS inhibited adipocyte differentiation of hMSCs in a concentration-dependent manner in the 0.156 to 2.5 μM range as indicated by morphological changes with Oil Red O staining, which is an index of lipid accumulation. The inhibitory effect was confirmed by a decrease in gene expression of specific adipocyte differentiation biomarkers including adipocyte protein 2, lipoprotein lipase, and adiponectin. Our study demonstrates that TCS inhibits adipocyte differentiation of hMSCs under concentrations that are not cytotoxic and in the range observed in human blood. -- Highlights: ► TCS is cytotoxic to un-induced hMSCs at concentrations ≥ 5.0 μM. ► TCS at concentrations ≤ 2.5 μM is not cytotoxic to induced hMSCs. ► TCS at non-cytotoxic concentrations inhibits lipid formation in induced hMSCs. ► TCS decreases the expression of specific biomarkers of adipocyte differentiation. ► TCS at concentrations observed in human blood inhibits adipogenesis of hMSCs.

Cytotoxicity and inhibitory effects of low-concentration triclosan on adipogenic differentiation of human mesenchymal stem cells

International Nuclear Information System (INIS)

Guo, Li-Wu; Wu, Qiangen; Green, Bridgett; Nolen, Greg; Shi, Leming; LoSurdo, Jessica; Deng, Helen; Bauer, Steven; Fang, Jia-Long; Ning, Baitang

2012-01-01

Humans at all ages are continually exposed to triclosan (TCS), a widely used antimicrobial agent that can be found in many daily hygiene products, such as toothpastes and shampoos; however, the toxicological and biological effects of TCS in the human body after long-term and low-concentration exposure are far from being well understood. In the current study, we investigated the effects of TCS on the differentiation of human mesenchymal stem cells (hMSCs) by measuring the cytotoxicity, morphological changes, lipid accumulation, and the expression of adipocyte differentiation biomarkers during 21-day adipogenesis. Significant cytotoxicity was observed in un-induced hMSCs treated with high-concentration TCS (≥ 5.0 μM TCS), but not with low-concentration treatments (≤ 2.5 μM TCS). TCS inhibited adipocyte differentiation of hMSCs in a concentration-dependent manner in the 0.156 to 2.5 μM range as indicated by morphological changes with Oil Red O staining, which is an index of lipid accumulation. The inhibitory effect was confirmed by a decrease in gene expression of specific adipocyte differentiation biomarkers including adipocyte protein 2, lipoprotein lipase, and adiponectin. Our study demonstrates that TCS inhibits adipocyte differentiation of hMSCs under concentrations that are not cytotoxic and in the range observed in human blood. -- Highlights: ► TCS is cytotoxic to un-induced hMSCs at concentrations ≥ 5.0 μM. ► TCS at concentrations ≤ 2.5 μM is not cytotoxic to induced hMSCs. ► TCS at non-cytotoxic concentrations inhibits lipid formation in induced hMSCs. ► TCS decreases the expression of specific biomarkers of adipocyte differentiation. ► TCS at concentrations observed in human blood inhibits adipogenesis of hMSCs.

Nootropic dipeptide noopept enhances inhibitory synaptic transmission in the hippocampus.

Science.gov (United States)

Povarov, I S; Kondratenko, R V; Derevyagin, V I; Ostrovskaya, R U; Skrebitskii, V G

2015-01-01

Application of nootropic agent Noopept on hippocampal slices from Wistar rats enhanced the inhibitory component of total current induced by stimulation of Shaffer collaterals in CA1 pyramidal neurons, but did not affect the excitatory component. A direct correlation between the increase in the amplitude of inhibitory current and agent concentration was found. The substance did not affect the release of inhibitory transmitters from terminals in the pyramidal neurons, which indicated changes in GABAergic interneurons.

Feasibility Studies on Pipeline Disposal of Concentrated Copper Tailings Slurry for Waste Minimization

Science.gov (United States)

Senapati, Pradipta Kumar; Mishra, Barada Kanta

2017-06-01

The conventional lean phase copper tailings slurry disposal systems create pollution all around the disposal area through seepage and flooding of waste slurry water. In order to reduce water consumption and minimize pollution, the pipeline disposal of these waste slurries at high solids concentrations may be considered as a viable option. The paper presents the rheological and pipeline flow characteristics of copper tailings samples in the solids concentration range of 65-72 % by weight. The tailings slurry indicated non-Newtonian behaviour at these solids concentrations and the rheological data were best fitted by Bingham plastic model. The influence of solids concentration on yield stress and plastic viscosity for the copper tailings samples were discussed. Using a high concentration test loop, pipeline experiments were conducted in a 50 mm nominal bore (NB) pipe by varying the pipe flow velocity from 1.5 to 3.5 m/s. A non-Newtonian Bingham plastic pressure drop model predicted the experimental data reasonably well for the concentrated tailings slurry. The pressure drop model was used for higher size pipes and the operating conditions for pipeline disposal of concentrated copper tailings slurry in a 200 mm NB pipe with respect to specific power consumption were discussed.

Medium Effects on Minimum Inhibitory Concentrations of Nylon-3 Polymers against E. coli

Science.gov (United States)

Choi, Heejun; Chakraborty, Saswata; Liu, Runhui; Gellman, Samuel H.; Weisshaar, James C.

2014-01-01

Minimum inhibitory concentrations (MICs) against E. coli were measured for three nylon-3 polymers using Luria-Bertani broth (LB), brain-heart infusion broth (BHI), and a chemically defined complete medium (EZRDM). The polymers differ in the ratio of hydrophobic to cationic subunits. The cationic homopolymer is inert against E. coli in BHI and LB, but becomes highly potent in EZRDM. A mixed hydrophobic/cationic polymer with a hydrophobic t-butylbenzoyl group at its N-terminus is effective in BHI, but becomes more effective in EZRDM. Supplementation of EZRDM with the tryptic digest of casein (often found in LB) recapitulates the LB and BHI behavior. Additional evidence suggests that polyanionic peptides present in LB and BHI may form electrostatic complexes with cationic polymers, decreasing activity by diminishing binding to the anionic lipopolysaccharide layer of E. coli. In contrast, two natural antimicrobial peptides show no medium effects. Thus, the use of a chemically defined medium helps to reveal factors that influence antimicrobial potency of cationic polymers and functional differences between these polymers and evolved antimicrobial peptides. PMID:25153714

Preparation of ACE Inhibitory Peptides from Mytilus coruscus Hydrolysate Using Uniform Design

Directory of Open Access Journals (Sweden)

Jin-Chao Wu

2013-01-01

Full Text Available The angiotensin-I-converting enzyme (ACE inhibitory peptides from mussel, Mytilus coruscus, were investigated and the variable factors, protease concentration, hydrolysis time, pH, and temperature, were optimized using Uniform Design, a new statistical experimental method. The results proved that the hydrolysate of alkali proteases had high ACE-inhibitory activity, especially the alkali protease E1. Optimization by Uniform Design showed that the best hydrolysis conditions for preparation of ACE-inhibitory peptides from Mytilus coruscus were protease concentration of 36.0 U/mL, hydrolysis time of 2.7 hours, pH 8.2, and Temperature at 59.5°C, respectively. The verification experiments under optimum conditions showed that the ACE-inhibitory activity (91.3% were agreed closely with the predicted activity of 90.7%. The amino acid composition analysis of Mytilus coruscus ACE-inhibitory peptides proved that it had high percent of lysine, leucine, glycine, aspartic acid, and glutamic acid.

Enzyme inhibitory activity of selected Philippine plants

International Nuclear Information System (INIS)

Sasotona, Joseph S.; Hernandez, Christine C.

2015-01-01

In the Philippines, the number one cause of death are cardiovascular diseases. Diseases linked with inflammation are proliferating. This research aims to identify plant extracts that have potential activity of cholesterol-lowering, anti-hypertension, anti-gout, anti-inflammatory and fat blocker agents. Although there are commercially available drugs to treat the aforementioned illnesses, these medicine have adverse side-effects, aside from the fact that they are expensive. The results of this study will serve as added knowledge to contribute to the development of cheaper, more readily available, and effective alternative medicine. 100 plant extracts from different areas in the Philippines have been tested for potential inhibitory activity against Hydroxymethylglutaryl-coenzyme A (HMG-CoA), Lipoxygenase, and Xanthine Oxidase. The plant samples were labeled with codes and distributed to laboratories for blind testing. The effective concentration of the samples tested for Xanthine oxidase is 100 ppm. Samples number 9, 11, 14, 29, 43, 46, and 50 have shown significant inhibitory activity at 78.7%, 78.4%, 70%, 89.2%, 79%, 67.4%, and 67.5% respectively. Samples tested for Lipoxygenase inhibition were set at 33ppm. Samples number 2, 37, 901, 1202, and 1204 have shown significant inhibitory activity at 66, 84.9%, 88.55%, 93.3%, and 84.7% respectively. For HMG-CoA inhibition, the effective concentration of the samples used was 100 ppm. Samples number 1 and 10 showed significant inhibitory activity at 90.1% and 81.8% respectively. (author)

Inhibitory effect of corn silk on skin pigmentation.

Science.gov (United States)

Choi, Sang Yoon; Lee, Yeonmi; Kim, Sung Soo; Ju, Hyun Min; Baek, Ji Hwoon; Park, Chul-Soo; Lee, Dong-Hyuk

2014-03-03

In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin production inhibitory effect at the same concentration. The corn silk extract did not suppress tyrosinase activity but greatly reduced the expression of tyrosinase in Melan-A cells. In addition, corn silk extract was applied to the human face with hyperpigmentation, and skin color was measured to examine the degree of skin pigment reduction. The application of corn silk extract on faces with hyperpigmentation significantly reduced skin pigmentation without abnormal reactions. Based on the results above, corn silk has good prospects for use as a material for suppressing skin pigmentation.

Inhibitory Effect of Corn Silk on Skin Pigmentation

Directory of Open Access Journals (Sweden)

Sang Yoon Choi

2014-03-01

Full Text Available In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin production inhibitory effect at the same concentration. The corn silk extract did not suppress tyrosinase activity but greatly reduced the expression of tyrosinase in Melan-A cells. In addition, corn silk extract was applied to the human face with hyperpigmentation, and skin color was measured to examine the degree of skin pigment reduction. The application of corn silk extract on faces with hyperpigmentation significantly reduced skin pigmentation without abnormal reactions. Based on the results above, corn silk has good prospects for use as a material for suppressing skin pigmentation.

Qualifying and quantifying minimal hepatic encephalopathy

DEFF Research Database (Denmark)

Morgan, Marsha Y; Amodio, Piero; Cook, Nicola A

2016-01-01

Minimal hepatic encephalopathy is the term applied to the neuropsychiatric status of patients with cirrhosis who are unimpaired on clinical examination but show alterations in neuropsychological tests exploring psychomotor speed/executive function and/or in neurophysiological variables. There is ......Minimal hepatic encephalopathy is the term applied to the neuropsychiatric status of patients with cirrhosis who are unimpaired on clinical examination but show alterations in neuropsychological tests exploring psychomotor speed/executive function and/or in neurophysiological variables...... analytical techniques may provide better diagnostic information while the advent of portable wireless headsets may facilitate more widespread use. A large number of other diagnostic tools have been validated for the diagnosis of minimal hepatic encephalopathy including Critical Flicker Frequency......, the Inhibitory Control Test, the Stroop test, the Scan package and the Continuous Reaction Time; each has its pros and cons; strengths and weaknesses; protagonists and detractors. Recent AASLD/EASL Practice Guidelines suggest that the diagnosis of minimal hepatic encephalopathy should be based on the PHES test...

Zeolites relieves inhibitory stress from high concentrations of long chain fatty acids.

Science.gov (United States)

Nordell, Erik; Hansson, Anna B; Karlsson, Martin

2013-12-01

Protein and fat rich slaughterhouse waste is a very attractive waste stream for the production of biogas because of the high biochemical methane potential of the substrate. The material has however some drawbacks as the sole material for biogas production due to the production of several process disturbing metabolites such as ammonia, sulfides and long chain fatty acids. We can in this work present results that show that zeolites have the potential to relieve inhibitory stress from the presence of long chain fatty acids. Moreover, the results strongly indicate that it is mainly acetic acid consumers that are most negatively affected by long chain fatty acids and that the mechanism of stress relief is an adsorption of long chain fatty acids to the zeolites. In addition to this, it is shown that the effect is immediate and that only a small amount of zeolites is necessary to cancel the inhibitory effect of long chain fatty acids. Copyright © 2013 Elsevier Ltd. All rights reserved.

Identification of dipeptidyl peptidase-IV inhibitory peptides from mare whey protein hydrolysates.

Science.gov (United States)

Song, J J; Wang, Q; Du, M; Ji, X M; Mao, X Y

2017-09-01

Inhibition of dipeptidyl peptidase-IV (DPP-IV) activity is a promising strategy for treatment of type 2 diabetes. In the current study, DPP-IV inhibitory peptides were identified from mare whey protein hydrolysates obtained by papain. The results showed that all the mare whey protein hydrolysates obtained at various hydrolysis durations possessed more potent DPP-IV inhibitory activity compared with intact whey protein. The 4-h hydrolysates showed the greatest DPP-IV inhibitory activity with half-maximal inhibitory concentration of 0.18 mg/mL. The 2 novel peptides from 4-h hydrolysate fractions separated by successive chromatographic steps were characterized by liquid chromatography-electrospray ionization tandem mass spectrometry. The novel peptides Asn-Leu-Glu-Ile-Ile-Leu-Arg and Thr-Gln-Met-Val-Asp-Glu-Glu-Ile-Met-Glu-Lys-Phe-Arg, which corresponded to β-lactoglobulin 1 f(71-77) and β-lactoglobulin 1 f(143-155), demonstrated DPP-IV inhibitory activity with half-maximal inhibitory concentrations of 86.34 and 69.84 μM, respectively. The DPP-IV inhibitory activity of the 2 peptides was retained or even improved after simulated gastrointestinal digestion in vitro. Our findings indicate that mare whey protein-derived peptides may possess potential as functional food ingredients in the management of type 2 diabetes. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Inhibitory Effect of Corn Silk on Skin Pigmentation

OpenAIRE

Sang Yoon Choi; Yeonmi Lee; Sung Soo Kim; Hyun Min Ju; Ji Hwoon Baek; Chul-Soo Park; Dong-Hyuk Lee

2014-01-01

In this study, the inhibitory effect of corn silk on melanin production was evaluated. This study was performed to investigate the inhibitory effect of corn silk on melanin production in Melan-A cells by measuring melanin production and protein expression. The corn silk extract applied on Melan-A cells at a concentration of 100 ppm decreased melanin production by 37.2% without cytotoxicity. This was a better result than arbutin, a positive whitening agent, which exhibited a 26.8% melanin prod...

Inhibitory effect of high NH{sub 4}{sup +}–N concentration on anaerobic biotreatment of fresh leachate from a municipal solid waste incineration plant

Energy Technology Data Exchange (ETDEWEB)

Liu, Zhao; Dang, Yan; Li, Caihua; Sun, Dezhi, E-mail: sdzlab@126.com

2015-09-15

Highlights: • High NH{sub 4}{sup +}–N concentrations inhibit anaerobic treatment of leachate. • Inhibitory effect of NH{sub 4}{sup +}–N concentrations on anaerobic granular sludge is reversible. • High NH{sub 4}{sup +}–N concentrations inhibit bioactivities of microorganisms instead of survival. - Abstract: Fresh leachate from municipal solid waste (MSW) incineration plants generally contains extremely high NH{sub 4}{sup +}–N concentration which could inhibit the bioactivity of microorganisms. The inhibitory effect of high NH{sub 4}{sup +}–N concentration on anaerobic biotreatment of fresh leachate from a MSW incineration plant in China has been investigated in this study. The inhibition processes was studied by both static tests and a laboratory-scale expanded granular sludge bed (EGSB) reactor. The specific methanogenic activity (SMA) of the microorganisms in anaerobic granular sludge was inhibited with the NH{sub 4}{sup +}–N concentration increasing to 1000 mg/L in static tests. As well the chemical oxygen demand (COD) removal efficiency and the methane yield decreased in the EGSB reactor, while the volatile fatty acids (VFAs) accumulated and extracellular polymeric substances (EPS) of the anaerobic granular sludge increased with NH{sub 4}{sup +}–N concentration rising to 1000 mg/L, without any rebounding during 30 days of operation. Decreasing NH{sub 4}{sup +}–N concentration to 500 mg/L in influent, the COD removal efficiency recovered to about 85% after 26 days. 1000 mg/L of NH{sub 4}{sup +}–N in leachate was suggested to be the inhibition threshold in EGSB reactor. High-throughput sequencing results showed little changes in microbial communities of the sludge for a high NH{sub 4}{sup +}–N concentration, indicating that the survival of most microorganisms was not affected under such a condition. It inhibited the bioactivity of the microorganisms, resulting in decrease of the COD removal efficiency.

Sub-inhibitory stress with essential oil affects enterotoxins production and essential oil susceptibility in Staphylococcus aureus.

Science.gov (United States)

Turchi, Barbara; Mancini, Simone; Pistelli, Luisa; Najar, Basma; Cerri, Domenico; Fratini, Filippo

2018-03-01

Fourteen wild strains of Staphylococcus aureus positive for gene sea were tested for enterotoxins production and the minimum inhibitory concentration of Leptospermum scoparium, Origanum majorana, Origanum vulgare, Satureja montana and Thymus vulgaris essential oils (EOs) were determined. After this trial, bacteria stressed with sub-inhibitory concentration of each EO were tested for enterotoxins production by an immunoenzymatic assay and resistance to the same EO. Oregano oil exhibited the highest antibacterial activity followed by manuka and thyme oils. After the exposure to a sub-inhibitory concentration of EOs, strains displayed an increased sensitivity in more than 95% of the cases. After treatment with oregano and marjoram EOs, few strains showed a modified enterotoxins production, while 43% of the strains were no longer able to produce enterotoxins after treatment with manuka EO. The results obtained in this study highlight that exposure to sub-inhibitory concentration of EO modifies strains enterotoxins production and EOs susceptibility profile.

Macrophage migration inhibitory factor as an incriminating agent in vitiligo.

Science.gov (United States)

Farag, Azza Gaber Antar; Hammam, Mostafa Ahmed; Habib, Mona SalahEldeen; Elnaidany, Nada Farag; Kamh, Mona Eaid

2018-03-01

Vitiligo is an autoimmune skin disorder in which the loss of melanocytes is mainly attributed to defective autoimmune mechanisms and, lately, there has been more emphasis on autoinflammatory mediators. Among these is the macrophage migration inhibitory factor, which is involved in many autoimmune skin diseases. However, little is known about the contribution of this factor to vitiligo vulgaris. To determine the hypothesized role of migration inhibitory factor in vitiligo via estimation of serum migration inhibitory factor levels and migration inhibitory factor mRNA concentrations in patients with vitiligo compared with healthy controls. We also aimed to assess whether there is a relationship between the values of serum migration inhibitory factor and/or migration inhibitory factor mRNA with disease duration, clinical type and severity in vitiligo patients. Evaluation of migration inhibitory factor serum level and migration inhibitory factor mRNA expression by ELISA and real-time PCR, respectively, were performed for 50 patients with different degrees of vitiligo severity and compared to 15 age- and gender-matched healthy volunteers as controls. There was a highly significant increase in serum migration inhibitory factor and migration inhibitory factor mRNA levels in vitiligo cases when compared to controls (pvitiligo patients, and each of them with duration and severity of vitiligo. In addition, patients with generalized vitiligo have significantly elevated serum migration inhibitory factor and mRNA levels than control subjects. Small number of investigated subjects. Migration inhibitory factor may have an active role in the development of vitiligo, and it may also be a useful index of disease severity. Consequently, migration inhibitory factor may be a new treatment target for vitiligo patients.

Galanin-immunoreactivity identifies a distinct population of inhibitory interneurons in laminae I-III of the rat spinal cord

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Watanabe Masahiko

2011-05-01

Full Text Available Abstract Background Inhibitory interneurons constitute 30-40% of neurons in laminae I-III and have an important anti-nociceptive role. However, because of the difficulty in classifying them we know little about their organisation. Previous studies have identified 3 non-overlapping groups of inhibitory interneuron, which contain neuropeptide Y (NPY, neuronal nitric oxide synthase (nNOS or parvalbumin, and have shown that these differ in postsynaptic targets. Some inhibitory interneurons contain galanin and the first aim of this study was to determine whether these form a different population from those containing NPY, nNOS or parvalbumin. We also estimated the proportion of neurons and GABAergic axons that contain galanin in laminae I-III. Results Galanin cells were concentrated in laminae I-IIo, with few in laminae IIi-III. Galanin showed minimal co-localisation with NPY, nNOS or parvalbumin in laminae I-II, but most galanin-containing cells in lamina III were nNOS-positive. Galanin cells constituted ~7%, 3% and 2% of all neurons in laminae I, II and III, and we estimate that this corresponds to 26%, 10% and 5% of the GABAergic neurons in these laminae. However, galanin was only found in ~6% of GABAergic boutons in laminae I-IIo, and ~1% of those in laminae IIi-III. Conclusions These results show that galanin, NPY, nNOS and parvalbumin can be used to define four distinct neurochemical populations of inhibitory interneurons. Together with results of a recent study, they suggest that the galanin and NPY populations account for around half of the inhibitory interneurons in lamina I and a quarter of those in lamina II.

Growth inhibitory alkaloids from mesquite (Prosopis juliflora (Sw.) DC.) leaves.

Science.gov (United States)

Nakano, Hiroshi; Nakajima, Eri; Hiradate, Syuntaro; Fujii, Yoshiharu; Yamada, Kosumi; Shigemori, Hideyuki; Hasegawa, Koji

2004-03-01

Plant growth inhibitory alkaloids were isolated from the extract of mesquite [Prosopis juliflora (Sw.) DC.] leaves. Their chemical structures were established by ESI-MS, 1H and 13C NMR spectra analysis. The I50 value (concentration required for 50% inhibition of control) for root growth of cress (Lepidium sativum L.) seedlings was 400 microM for 3''''-oxo-juliprosopine, 500 microM for secojuliprosopinal, and 100 microM for a (1:1) mixture of 3-oxo-juliprosine and 3'-oxo-juliprosine, respectively. On the other hand, the minimum concentration exhibiting inhibitory effect on shoot growth of cress seedlings was 10 microM for 3''''-oxo-juliprosopine, 100 microM for secojuliprosopinal, and 1 microM for a (1:1) mixture of 3-oxo-juliprosine and 3'-oxo-juliprosine, respectively. Among these compounds, a (1:1) mixture of 3-oxo-juliprosine and 3'-oxo-juliprosine exhibited the strongest inhibitory effect on the growth of cress seedlings.

Comparison of Heuristics for Inhibitory Rule Optimization

KAUST Repository

Alsolami, Fawaz

2014-09-13

Knowledge representation and extraction are very important tasks in data mining. In this work, we proposed a variety of rule-based greedy algorithms that able to obtain knowledge contained in a given dataset as a series of inhibitory rules containing an expression “attribute ≠ value” on the right-hand side. The main goal of this paper is to determine based on rule characteristics, rule length and coverage, whether the proposed rule heuristics are statistically significantly different or not; if so, we aim to identify the best performing rule heuristics for minimization of rule length and maximization of rule coverage. Friedman test with Nemenyi post-hoc are used to compare the greedy algorithms statistically against each other for length and coverage. The experiments are carried out on real datasets from UCI Machine Learning Repository. For leading heuristics, the constructed rules are compared with optimal ones obtained based on dynamic programming approach. The results seem to be promising for the best heuristics: the average relative difference between length (coverage) of constructed and optimal rules is at most 2.27% (7%, respectively). Furthermore, the quality of classifiers based on sets of inhibitory rules constructed by the considered heuristics are compared against each other, and the results show that the three best heuristics from the point of view classification accuracy coincides with the three well-performed heuristics from the point of view of rule length minimization.

The effect of subminimal inhibitory concentrations of penicillin on growth rate and haemolysin activity of group G Streptococcus

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Verônica V. Vieira

1993-09-01

Full Text Available The influence of the subminimal inhibitory concentrations (1/3 and 1/4 of the MIC of penicillin on growth rate and on haemolysin production of a strain of group G Streptococcus was studied. It was shown that 1/3 of the MIC almost completely inhibited the bacterial growth, but it was not able to inhibit haemolysin activity in the culture supernate. The generation time of bacteria grown in 1/4 of the MIC was approximately twice longer than that of the control culture. In all cultures, the haemolysin, after being produced (or liberated, reached a peak and decreased to low levels, which could suggest that group G Streptococcus produces some end products of metabolism that are able to inhibit haemolysin activity.

Degree of synchronization modulated by inhibitory neurons in clustered excitatory-inhibitory recurrent networks

Science.gov (United States)

Li, Huiyan; Sun, Xiaojuan; Xiao, Jinghua

2018-01-01

An excitatory-inhibitory recurrent neuronal network is established to numerically study the effect of inhibitory neurons on the synchronization degree of neuronal systems. The obtained results show that, with the number of inhibitory neurons and the coupling strength from an inhibitory neuron to an excitatory neuron increasing, inhibitory neurons can not only reduce the synchronization degree when the synchronization degree of the excitatory population is initially higher, but also enhance it when it is initially lower. Meanwhile, inhibitory neurons could also help the neuronal networks to maintain moderate synchronized states. In this paper, we call this effect as modulation effect of inhibitory neurons. With the obtained results, it is further revealed that the ratio of excitatory neurons to inhibitory neurons being nearly 4 : 1 is an economic and affordable choice for inhibitory neurons to realize this modulation effect.

The inhibitory effect of different concentrations of KH902 eye drops on corneal neovascularization induced by alkali burn

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Yan Wu

2017-01-01

Full Text Available Purpose: The aim of this study was to evaluate the inhibitory effect of different concentrations of KH902 eye drops on rabbit corneal neovascularization (CNV induced by alkali burn. Methods: Forty-eight adult rabbits were randomized into four groups after alkali burning: Group A (2.5 mg/ml, Group B (5 mg/ml, and Group C (10 mg/ml by different concentrations of KH902 eye drops and Group D by saline solution as control with three times a day for 2 weeks. At days 7, 14, and 28, the anterior segment photographs, confocal microscopy, and histopathology were performed to evaluate corneal opacity, neovascularization, inflammatory cell density, vessel size, and edema. Immunohistochemistry was applied to analyze the vascular endothelial growth factor (VEGF level. Results: (1 The CNV in the medicine-treated groups showed a reduction without obvious corneal side effects histologically. (2 Compared to the control group, the three medicine-treated groups showed a reduction in the VEGF levels and CNV areas on days 7, 14, and 28 and in the inflammatory cell density on days 14 and 28 (P 0.05. Conclusion: KH902 eye drops in lower concentration showed an obvious reduction of the CNV growing for rabbit corneal alkali burn without side effects.

Steady-state metabolite concentrations reflect a balance between maximizing enzyme efficiency and minimizing total metabolite load.

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Naama Tepper

Full Text Available Steady-state metabolite concentrations in a microorganism typically span several orders of magnitude. The underlying principles governing these concentrations remain poorly understood. Here, we hypothesize that observed variation can be explained in terms of a compromise between factors that favor minimizing metabolite pool sizes (e.g. limited solvent capacity and the need to effectively utilize existing enzymes. The latter requires adequate thermodynamic driving force in metabolic reactions so that forward flux substantially exceeds reverse flux. To test this hypothesis, we developed a method, metabolic tug-of-war (mTOW, which computes steady-state metabolite concentrations in microorganisms on a genome-scale. mTOW is shown to explain up to 55% of the observed variation in measured metabolite concentrations in E. coli and C. acetobutylicum across various growth media. Our approach, based strictly on first thermodynamic principles, is the first method that successfully predicts high-throughput metabolite concentration data in bacteria across conditions.

Inhibitory effect of 1,2,4-triazole-ciprofloxacin hybrids on Haemophilus parainfluenzae and Haemophilus influenzae biofilm formation in vitro under stationary conditions.

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Kosikowska, Urszula; Andrzejczuk, Sylwia; Plech, Tomasz; Malm, Anna

2016-10-01

Haemophilus parainfluenzae and Haemophilus influenzae, upper respiratory tract microbiota representatives, are able to colonize natural and artificial surfaces as biofilm. The aim of the present study was to assay the effect of ten 1,2,4-triazole-ciprofloxacin hybrids on planktonic or biofilm-forming haemophili cells in vitro under stationary conditions on the basis of MICs (minimal inhibitory concentrations) and MBICs (minimal biofilm inhibitory concentrations). In addition, anti-adhesive properties of these compounds were examined. The reference strains of H. parainfluenzae and H. influenzae were included. The broth microdilution microtiter plate (MTP) method with twofold dilution of the compounds, or ciprofloxacin (reference agent) in 96-well polystyrene microplates, was used. The optical density (OD) reading was made spectrophotometrically at a wavelength of 570 nm (OD570) both to measure bacterial growth and to detect biofilm-forming cells under the same conditions with 0.1% crystal violet. The following values of parameters were estimated for 1,2,4-triazole-ciprofloxacin hybrids - MIC = 0.03-15.63 mg/L, MBIC = 0.03-15.63 mg/L, MBIC/MIC = 0.125-8, depending on the compound, and for ciprofloxacin - MIC = 0.03-0.06 mg/L, MBIC = 0.03-0.12 mg/L, MBIC/MIC = 1-2. The observed strong anti-adhesive properties (95-100% inhibition) of the tested compounds were reversible during long-term incubation at subinhibitory concentrations. Thus, 1,2,4-triazole-ciprofloxacin hybrids may be considered as starting compounds for designing improved agents not only against planktonic but also against biofilm-forming Haemophilus spp. cells. Copyright © 2016 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

Inhibitory noise

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Alain Destexhe

2010-03-01

Full Text Available Cortical neurons in vivo may operate in high-conductance states, in which the major part of the neuron's input conductance is due to synaptic activity, sometimes several-fold larger than the resting conductance. We examine here the contribution of inhibition in such high-conductance states. At the level of the absolute conductance values, several studies have shown that cortical neurons in vivo are characterized by strong inhibitory conductances. However, conductances are balanced and spiking activity is mostly determined by fluctuations, but not much is known about excitatory and inhibitory contributions to these fluctuations. Models and dynamic-clamp experiments show that, during high-conductance states, spikes are mainly determined by fluctuations of inhibition, or by inhibitory noise. This stands in contrast to low-conductance states, in which excitatory conductances determine spiking activity. To determine these contributions from experimental data, maximum likelihood methods can be designed and applied to intracellular recordings in vivo. Such methods indicate that action potentials are indeed mostly correlated with inhibitory fluctuations in awake animals. These results argue for a determinant role for inhibitory fluctuations in evoking spikes, and do not support feed-forward modes of processing, for which opposite patterns are predicted.

Alpha-glucosidase inhibitory effect and inorganic constituents of Phyllanthus amarus Schum. & Thonn. ash

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Malinee Wongnawa

2014-10-01

Full Text Available This study investigated the -glucosidase inhibitory effect and determined the concentration of some inorganic constituents in P. amarus ash. Oral glucose and sucrose tolerance test were performed on normal mice. In vitro -glucosidase inhibitory activity was evaluated by using yeast a-glucosidase. The element concentrations were measured by inductively coupled plasma (ICP spectroscopy. Single oral administration of P. amarus ash did not show antihyperglycemic effect after glucose administration, but decreased blood glucose level after sucrose administration. The ash showed -glucosidase inhibitory activity in vitro with IC50 of 982 mg/mL. The concentrations of K, Ca, Mg, Mn, Fe, Zn, Cu, Pb, Cr, Ni and Co in P. amarus ash were 35049.80±340.64, 3337.24±52.10, 1368.52±13.29, 90.81±1.34, 87.68±1.15, 18.28±0.22, 4.69±0.07, 1.07±0.15, 0.29±0.03, 0.20±0.04 and 0.10±0.02 mg/g, respectively. These results indicate that the antihyperglycemic effect of P. amarus ash might be partly due to the -glucosidase inhibitory activity of the inorganic constituents.

Characterization of a translation inhibitory protein from Luffa aegyptiaca.

Science.gov (United States)

Ramakrishnan, S; Enghlid, J J; Bryant, H L; Xu, F J

1989-04-28

A protein with a molecular weight of about 30,000 was purified from the seeds of Luffa aegyptiaca. This protein inhibited cell free translation at pM concentrations. In spite of functional similarity to other ribosomal inhibitory proteins, the NH2-terminal analysis did not show any significant homology. Competitive inhibition studies indicate no immunological crossreactivity between the inhibitory protein from Luffa aegyptiaca, pokeweed antiviral protein (PAP) and recombinant ricin A chain. Chemical linkage of the protein to a monoclonal antibody reactive to transferrin receptor resulted in a highly cytotoxic conjugate.

Inhibitory Effects of Respiration Inhibitors on Aflatoxin Production

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Shohei Sakuda

2014-03-01

Full Text Available Aflatoxin production inhibitors, which do not inhibit the growth of aflatoxigenic fungi, may be used to control aflatoxin without incurring a rapid spread of resistant strains. A respiration inhibitor that inhibits aflatoxin production was identified during a screening process for natural, aflatoxin-production inhibitors. This prompted us to evaluate respiration inhibitors as potential aflatoxin control agents. The inhibitory activities of four natural inhibitors, seven synthetic miticides, and nine synthetic fungicides were evaluated on aflatoxin production in Aspergillus parasiticus. All of the natural inhibitors (rotenone, siccanin, aptenin A5, and antimycin A inhibited fungal aflatoxin production with IC50 values around 10 µM. Among the synthetic miticides, pyridaben, fluacrypyrim, and tolfenpyrad exhibited strong inhibitory activities with IC50 values less than 0.2 µM, whereas cyflumetofen did not show significant inhibitory activity. Of the synthetic fungicides, boscalid, pyribencarb, azoxystrobin, pyraclostrobin, and kresoxim-methyl demonstrated strong inhibitory activities, with IC50 values less than 0.5 µM. Fungal growth was not significantly affected by any of the inhibitors tested at concentrations used. There was no correlation observed between the targets of respiration inhibitors (complexes I, II, and III and their IC50 values for aflatoxin-production inhibitory activity. This study suggests that respiration inhibitors, including commonly used pesticides, are useful for aflatoxin control.

Inhibitory Effects of Respiration Inhibitors on Aflatoxin Production

Science.gov (United States)

Sakuda, Shohei; Prabowo, Diyan Febri; Takagi, Keiko; Shiomi, Kazuro; Mori, Mihoko; Ōmura, Satoshi; Nagasawa, Hiromichi

2014-01-01

Aflatoxin production inhibitors, which do not inhibit the growth of aflatoxigenic fungi, may be used to control aflatoxin without incurring a rapid spread of resistant strains. A respiration inhibitor that inhibits aflatoxin production was identified during a screening process for natural, aflatoxin-production inhibitors. This prompted us to evaluate respiration inhibitors as potential aflatoxin control agents. The inhibitory activities of four natural inhibitors, seven synthetic miticides, and nine synthetic fungicides were evaluated on aflatoxin production in Aspergillus parasiticus. All of the natural inhibitors (rotenone, siccanin, aptenin A5, and antimycin A) inhibited fungal aflatoxin production with IC50 values around 10 µM. Among the synthetic miticides, pyridaben, fluacrypyrim, and tolfenpyrad exhibited strong inhibitory activities with IC50 values less than 0.2 µM, whereas cyflumetofen did not show significant inhibitory activity. Of the synthetic fungicides, boscalid, pyribencarb, azoxystrobin, pyraclostrobin, and kresoxim-methyl demonstrated strong inhibitory activities, with IC50 values less than 0.5 µM. Fungal growth was not significantly affected by any of the inhibitors tested at concentrations used. There was no correlation observed between the targets of respiration inhibitors (complexes I, II, and III) and their IC50 values for aflatoxin-production inhibitory activity. This study suggests that respiration inhibitors, including commonly used pesticides, are useful for aflatoxin control. PMID:24674936

Growth Behavior of E. coli, Enterococcus and Staphylococcus Species in the Presence and Absence of Sub-inhibitory Antibiotic Concentrations: Consequences for Interpretation of Culture-Based Data.

Science.gov (United States)

Heß, Stefanie; Gallert, Claudia

2016-11-01

Culture-based approaches are used to monitor, e.g., drinking water or bathing water quality and to investigate species diversity and antibiotic resistance levels in environmental samples. For health risk assessment, it is important to know whether the growing cultures display the actual abundance of, e.g., clinically relevant antibiotic resistance phenotypes such as vancomycin-resistant Enterococcus faecium/Enterococcus faecalis (VRE) or methicillin-resistant Staphylococcus aureus. In addition, it is important to know whether sub-inhibitory antibiotic concentrations, which are present in surface waters, favor the growth of antibiotic-resistant strains. Therefore, clinically relevant bacteria were isolated from different water sources and the growth behavior of 58 Escherichia coli, 71 Enterococcus, and 120 Staphylococcus isolates, belonging to different species and revealing different antibiotic resistance patterns, was studied with respect to "environmental" antibiotic concentrations. The finding that VRE could only be detected after specific enrichment can be explained by their slow growth compared to non-resistant strains. Interpreting their absence in standardized culture-based methods as nonexistent might be a fallacy. Sub-inhibitory antibiotic concentrations that were detected in sewage and receiving river water did not specifically promote antibiotic-resistant strains. Generally, those antibiotics that influenced cell metabolism directly led to slightly reduced growth rates and less than maximal optical densities after 48 h of incubation.

Concentrations of antibiotics predicted to select for resistant bacteria: Proposed limits for environmental regulation.

Science.gov (United States)

Bengtsson-Palme, Johan; Larsson, D G Joakim

2016-01-01

There are concerns that selection pressure from antibiotics in the environment may accelerate the evolution and dissemination of antibiotic-resistant pathogens. Nevertheless, there is currently no regulatory system that takes such risks into account. In part, this is due to limited knowledge of environmental concentrations that might exert selection for resistant bacteria. To experimentally determine minimal selective concentrations in complex microbial ecosystems for all antibiotics would involve considerable effort. In this work, our aim was to estimate upper boundaries for selective concentrations for all common antibiotics, based on the assumption that selective concentrations a priori need to be lower than those completely inhibiting growth. Data on Minimal Inhibitory Concentrations (MICs) were obtained for 111 antibiotics from the public EUCAST database. The 1% lowest observed MICs were identified, and to compensate for limited species coverage, predicted lowest MICs adjusted for the number of tested species were extrapolated through modeling. Predicted No Effect Concentrations (PNECs) for resistance selection were then assessed using an assessment factor of 10 to account for differences between MICs and minimal selective concentrations. The resulting PNECs ranged from 8 ng/L to 64 μg/L. Furthermore, the link between taxonomic similarity between species and lowest MIC was weak. This work provides estimated upper boundaries for selective concentrations (lowest MICs) and PNECs for resistance selection for all common antibiotics. In most cases, PNECs for selection of resistance were below available PNECs for ecotoxicological effects. The generated PNECs can guide implementation of compound-specific emission limits that take into account risks for resistance promotion. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Low concentration of sodium bicarbonate improves the bioactive compound levels and antioxidant and α-glucosidase inhibitory activities of tartary buckwheat sprouts.

Science.gov (United States)

Qin, Peiyou; Wei, Aichun; Zhao, Degang; Yao, Yang; Yang, Xiushi; Dun, Baoqing; Ren, Guixing

2017-06-01

This study aimed to investigate the effects of different concentrations of sodium bicarbonate (NaHCO 3 ) on the accumulation of flavonoids, total phenolics and d-chiro-inositol (DCI), as well as the antioxidant and α-glucosidase inhibitory activities, in tartary buckwheat sprouts. Treatment with low concentrations of NaHCO 3 (0.05, 0.1, and 0.2%) resulted in an increase in flavonoids, total phenolic compounds and DCI concentrations, and improved DPPH radical-scavenging and α-glucosidase inhibition activities compared with the control (0%). The highest levels of total flavonoids (26.69mg/g DW), individual flavonoids (rutin, isoquercitrin, quercetin, and kaempferol), total phenolic compounds (29.31mg/g DW), DCI (12.56mg/g DW), as well as antioxidant and α-glucosidase inhibition activities, were observed in tartary buckwheat sprouts treated with 0.05% NaHCO 3 for 96h. These results indicated that appropriate treatment with NaHCO 3 could improve the healthy benefits of tartary buckwheat sprouts. Copyright © 2016 Elsevier Ltd. All rights reserved.

Using stochastic cell division and death to probe minimal units of cellular replication

Science.gov (United States)

Chib, Savita; Das, Suman; Venkatesan, Soumya; Sai Narain Seshasayee, Aswin; Thattai, Mukund

2018-03-01

The invariant cell initiation mass measured in bacterial growth experiments has been interpreted as a minimal unit of cellular replication. Here we argue that the existence of such minimal units induces a coupling between the rates of stochastic cell division and death. To probe this coupling we tracked live and dead cells in Escherichia coli populations treated with a ribosome-targeting antibiotic. We find that the growth exponent from macroscopic cell growth or decay measurements can be represented as the difference of microscopic first-order cell division and death rates. The boundary between cell growth and decay, at which the number of live cells remains constant over time, occurs at the minimal inhibitory concentration (MIC) of the antibiotic. This state appears macroscopically static but is microscopically dynamic: division and death rates exactly cancel at MIC but each is remarkably high, reaching 60% of the antibiotic-free division rate. A stochastic model of cells as collections of minimal replicating units we term ‘widgets’ reproduces both steady-state and transient features of our experiments. Sub-cellular fluctuations of widget numbers stochastically drive each new daughter cell to one of two alternate fates, division or death. First-order division or death rates emerge as eigenvalues of a stationary Markov process, and can be expressed in terms of the widget’s molecular properties. High division and death rates at MIC arise due to low mean and high relative fluctuations of widget number. Isolating cells at the threshold of irreversible death might allow molecular characterization of this minimal replication unit.

Susceptibility of Haemophilus equigenitalis, the causal agent of contagious equine metritis, to 31 antimicrobial agents.

Science.gov (United States)

Sugimoto, C; Isayama, Y; Kashiwazaki, M; Mitani, K

1981-01-01

The minimal inhibitory concentrations of 31 antimicrobial agents were determined for 99 isolates of Haemophilus equigenitalis by the agar dilution method. All the isolates showed good susceptibility to 26 antimicrobial agents tests, minimal inhibitory concentrations of which were less than 3.13 micrograms/ml for more than 90% of the isolates. Of these agents, 4 macrolides (erythromycin, oleandomycin, kitasamycin, tylosin), 3 tetracyclines (tetracycline, chlortetracycline, oxytetracycline), 1 peptide (colistin), 1 penicillin (ampicillin) and 1 pleuromutilin (tiamulin) were the most active agents, showing a minimal inhibitory concentration of less than 0.39 micrograms/ml for more than 90% of the isolates. The growth of more than 90% of the isolates was not inhibited by 800 micrograms/ml of streptomycin.

In vitro sensitivity of medically significant Fusarium species to various antimycotics.

Science.gov (United States)

Sekhon, A S; Padhye, A A; Garg, A K; Ahmad, H; Moledina, N

1994-01-01

Sixteen isolates belonging to Fusarium chlamydosporum (n = 4), Fusarium equiseti (n = 1), Fusarium moniliforme (n = 2), Fusarium oxysporum (n = 3), Fusarium proliferatum (n = 1), and Fusarium solani (n = 5) were tested against amphotericin B, 5-fluorocytosine, fluconazole, itraconazole, ketoconazole, JAI-amphotericin B (water-soluble compound), hamycin and amphotericin B combined with 5-fluorocytosine, using antibiotic medium M3, high-resolution broth (pH 7.1), Sabouraud's dextrose, and yeast-nitrogen broth media (1 ml/tube). The minimal inhibitory and minimal fungicidal concentrations of 5-fluorocytosine and fluconazole for all species were > 100 micrograms/ml. All Fusarium isolates, except F. equiseti (3.125 micrograms), gave minimal inhibitory concentrations of 12.5-100 micrograms/ml for hamycin. The values for amphotericin B, itraconazole, ketoconazole, JAI-amphotericin B, and amphotericin B combined with 5-fluorocytosine were 1.56-100, 0.78-50, 3.125-100,50-100, and 1.56 to > 100 micrograms/ml, respectively. Although a wide range of minimal inhibitory concentrations was recorded for most of the isolates studied, it appears that some--F. solani, F. oxysporum, F. chlamydosporum, F. equiseti, and F. moliniforme--were more susceptible to amphotericin B, itraconazole, ketoconazole, hamycin, and amphotericin B in the presence of 5-fluorocytosine. All isolates showed resistance to 5-fluorocytosine and fluconazole. The minimal fungicidal concentrations were either the same or several times higher than the minimal inhibitory concentrations.

The determination of minimum inhibitory concentrations of selected antimicrobials for porcine Haemophilus parasuis isolates from the Czech Republic

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Kateřina Nedbalcová

2017-01-01

Full Text Available Haemophilus parasuis isolates obtained from pigs in the Czech Republic were tested for their susceptibility to amoxicillin, penicillin, ceftiofur, enrofloxacin, tetracycline, and tulathromycin by determination of minimum inhibitory concentrations using the broth microdilution method. The H. parasuis isolates were mostly susceptible to majority of tested antimicrobials (amoxicillin 90%, penicillin 73.3%, enrofloxacin 83.3%, and tulathromycin 83.3%. All isolates were susceptible to ceftiofur. On the other hand, no isolate was susceptible to tetracycline, 30% of tested isolates were intermediately susceptible, and 70% were resistant. These findings indicate that tested antimicrobials with the exception of tetracycline should be the preferred option used for the treatment of infection caused by H. parasuis but due to the potential transmission of resistance from animals to humans, the use of ceftiofur is considered as a last resort option in antimicrobial treatment of animals.

Inhibitory coupling between inhibitory interneurons in the spinal cord dorsal horn

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Ribeiro-da-Silva Alfredo

2009-05-01

Full Text Available Abstract Local inhibitory interneurons in the dorsal horn play an important role in the control of excitability at the segmental level and thus determine how nociceptive information is relayed to higher structures. Regulation of inhibitory interneuron activity may therefore have critical consequences on pain perception. Indeed, disinhibition of dorsal horn neuronal networks disrupts the balance between excitation and inhibition and is believed to be a key mechanism underlying different forms of pain hypersensitivity and chronic pain states. In this context, studying the source and the synaptic properties of the inhibitory inputs that the inhibitory interneurons receive is important in order to predict the impact of drug action at the network level. To address this, we studied inhibitory synaptic transmission in lamina II inhibitory interneurons identified under visual guidance in spinal slices taken from transgenic mice expressing enhanced green fluorescent protein (EGFP under the control of the GAD promoter. The majority of these cells fired tonically to a long depolarizing current pulse. Monosynaptically evoked inhibitory postsynaptic currents (eIPSCs in these cells were mediated by both GABAA and glycine receptors. Consistent with this, both GABAA and glycine receptor-mediated miniature IPSCs were recorded in all of the cells. These inhibitory inputs originated at least in part from local lamina II interneurons as verified by simultaneous recordings from pairs of EGFP+ cells. These synapses appeared to have low release probability and displayed potentiation and asynchronous release upon repeated activation. In summary, we report on a previously unexamined component of the dorsal horn circuitry that likely constitutes an essential element of the fine tuning of nociception.

Cell cycle control by a minimal Cdk network.

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Claude Gérard

2015-02-01

Full Text Available In present-day eukaryotes, the cell division cycle is controlled by a complex network of interacting proteins, including members of the cyclin and cyclin-dependent protein kinase (Cdk families, and the Anaphase Promoting Complex (APC. Successful progression through the cell cycle depends on precise, temporally ordered regulation of the functions of these proteins. In light of this complexity, it is surprising that in fission yeast, a minimal Cdk network consisting of a single cyclin-Cdk fusion protein can control DNA synthesis and mitosis in a manner that is indistinguishable from wild type. To improve our understanding of the cell cycle regulatory network, we built and analysed a mathematical model of the molecular interactions controlling the G1/S and G2/M transitions in these minimal cells. The model accounts for all observed properties of yeast strains operating with the fusion protein. Importantly, coupling the model's predictions with experimental analysis of alternative minimal cells, we uncover an explanation for the unexpected fact that elimination of inhibitory phosphorylation of Cdk is benign in these strains while it strongly affects normal cells. Furthermore, in the strain without inhibitory phosphorylation of the fusion protein, the distribution of cell size at division is unusually broad, an observation that is accounted for by stochastic simulations of the model. Our approach provides novel insights into the organization and quantitative regulation of wild type cell cycle progression. In particular, it leads us to propose a new mechanistic model for the phenomenon of mitotic catastrophe, relying on a combination of unregulated, multi-cyclin-dependent Cdk activities.

Simulated inhibitory effects of typical byproducts of biomass ...

African Journals Online (AJOL)

Aghomotsegin

2015-07-29

Jul 29, 2015 ... comparative inhibitory effects of acetic acid and vanillin on the ... Different concentrations of inhibitors were spiked in the fermentation ... hardwood and municipal solid wastes. ... done at the cost of an extended lag phase and reduces ..... Formation of acetic acid and lactic acid during fermentation and in ...

Inhibitory effects of ZnO nanoparticles on aerobic wastewater biofilms from oxygen concentration profiles determined by microelectrodes

International Nuclear Information System (INIS)

Hou, Jun; Miao, Lingzhan; Wang, Chao; Wang, Peifang; Ao, Yanhui; Qian, Jin; Dai, Shanshan

2014-01-01

Highlights: • Temporal and spatial inhibitory effects of ZnO NPs on biofilms were investigated. • 50 mg/L nano-ZnO inhibited the microbial activities only in biofilm outer layer. • Adsorbed ZnO NPs had no adverse effects on the cell membrane integrity of biofilms. • Dissolution of ZnO NPs to toxic zinc ions was the main mechanism of toxicity. - Abstract: The presence of ZnO NPs in waste streams can negatively affect the efficiency of biological nutrient removal from wastewater. However, details of the toxic effects of ZnO NPs on microbial activities of wastewater biofilms have not yet been reported. In this study, the temporal and spatial inhibitory effects of ZnO NPs on the O 2 respiration activities of aerobic wastewater biofilms were investigated using an O 2 microelectrode. The resulting time–course microelectrode measurements demonstrated that ZnO NPs inhibited O 2 respiration within 2 h. The spatial distributions of net specific O 2 respiration were determined in biofilms with and without treatment of 5 or 50 mg/L ZnO NPs. The results showed that 50 mg/L of nano-ZnO inhibited the microbial activities only in the outer layer (∼200 μm) of the biofilms, and bacteria present in the deeper parts of the biofilms became even more active. Scanning electron microscopy (SEM) analysis showed that the ZnO NPs were adsorbed onto the biofilm, but these NPs had no adverse effects on the cell membrane integrity of the biofilms. It was found that the inhibition of O 2 respiration induced by higher concentrations of ZnO NPs (50 mg/L) was mainly due to the release of zinc ions by dissolution of the ZnO NPs

Inhibitory effects of ZnO nanoparticles on aerobic wastewater biofilms from oxygen concentration profiles determined by microelectrodes

Energy Technology Data Exchange (ETDEWEB)

Hou, Jun [Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098 (China); College of Environment, Hohai University, Nanjing 210098 (China); Miao, Lingzhan, E-mail: mlz1988@126.com [Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098 (China); College of Environment, Hohai University, Nanjing 210098 (China); Wang, Chao, E-mail: hhuhjy973@126.com [Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098 (China); College of Environment, Hohai University, Nanjing 210098 (China); Wang, Peifang; Ao, Yanhui; Qian, Jin; Dai, Shanshan [Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098 (China); College of Environment, Hohai University, Nanjing 210098 (China)

2014-07-15

Highlights: • Temporal and spatial inhibitory effects of ZnO NPs on biofilms were investigated. • 50 mg/L nano-ZnO inhibited the microbial activities only in biofilm outer layer. • Adsorbed ZnO NPs had no adverse effects on the cell membrane integrity of biofilms. • Dissolution of ZnO NPs to toxic zinc ions was the main mechanism of toxicity. - Abstract: The presence of ZnO NPs in waste streams can negatively affect the efficiency of biological nutrient removal from wastewater. However, details of the toxic effects of ZnO NPs on microbial activities of wastewater biofilms have not yet been reported. In this study, the temporal and spatial inhibitory effects of ZnO NPs on the O{sub 2} respiration activities of aerobic wastewater biofilms were investigated using an O{sub 2} microelectrode. The resulting time–course microelectrode measurements demonstrated that ZnO NPs inhibited O{sub 2} respiration within 2 h. The spatial distributions of net specific O{sub 2} respiration were determined in biofilms with and without treatment of 5 or 50 mg/L ZnO NPs. The results showed that 50 mg/L of nano-ZnO inhibited the microbial activities only in the outer layer (∼200 μm) of the biofilms, and bacteria present in the deeper parts of the biofilms became even more active. Scanning electron microscopy (SEM) analysis showed that the ZnO NPs were adsorbed onto the biofilm, but these NPs had no adverse effects on the cell membrane integrity of the biofilms. It was found that the inhibition of O{sub 2} respiration induced by higher concentrations of ZnO NPs (50 mg/L) was mainly due to the release of zinc ions by dissolution of the ZnO NPs.

Inhibitory effect of burdock leaves on elastase and tyrosinase activity

Science.gov (United States)

Horng, Chi-Ting; Wu, Hsing-Chen; Chiang, Ni-Na; Lee, Chiu-Fang; Huang, Yu-Syuan; Wang, Hui-Yun; Yang, Jai-Sing; Chen, Fu-An

2017-01-01

Burdock (Arctium lappa L.) leaves generate a considerable amount of waste following burdock root harvest in Taiwan. To increase the use of burdock leaves, the present study investigated the optimal methods for producing burdock leaf extract (BLE) with high antioxidant polyphenolic content, including drying methods and solvent extraction concentration. In addition, the elastase and tyrosinase inhibitory activity of BLE was examined. Burdock leaves were dried by four methods: Shadow drying, oven drying, sun drying and freeze-drying. The extract solution was then subjected to total polyphenol content analysis and the method that produced BLE with the highest amount of total antioxidant components was taken forward for further analysis. The 1,1-diphenyl-2-pycrylhydrazyl scavenging, antielastase and antityrosinase activity of the BLE were measured to enable the evaluation of the antioxidant and skin aging-associated enzyme inhibitory activities of BLE. The results indicated that the total polyphenolic content following extraction with ethanol (EtOH) was highest using the freeze-drying method, followed by the oven drying, shadow drying and sun drying methods. BLE yielded a higher polyphenol content and stronger antioxidant activity as the ratio of the aqueous content of the extraction solvent used increased. BLE possesses marked tyrosinase and elastase inhibitory activities, with its antielastase activity notably stronger compared with its antityrosinase activity. These results indicate that the concentration of the extraction solvent was associated with the antioxidant and skin aging-associated enzyme inhibitory activity of BLE. The reactive oxygen species scavenging theory of skin aging may explain the tyrosinase and elastase inhibitory activity of BLE. In conclusion, the optimal method for obtaining BLE with a high antioxidant polyphenolic content was freeze-drying followed by 30–50% EtOH extraction. In addition, the antielastase and antityrosinase activities of the

Angiotensin I-Converting Enzyme (ACE Inhibitory Activity and ACE Inhibitory Peptides of Salmon (Salmo salar Protein Hydrolysates Obtained by Human and Porcine Gastrointestinal Enzymes

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Małgorzata Darewicz

2014-08-01

Full Text Available The objectives of the present study were two-fold: first, to detect whether salmon protein fractions possess angiotensin I-converting enzyme (ACE inhibitory properties and whether salmon proteins can release ACE inhibitory peptides during a sequential in vitro hydrolysis (with commercial porcine enzymes and ex vivo digestion (with human gastrointestinal enzymes. Secondly, to evaluate the ACE inhibitory activity of generated hydrolysates. A two-step ex vivo and in vitro model digestion was performed to simulate the human digestion process. Salmon proteins were degraded more efficiently by porcine enzymes than by human gastrointestinal juices and sarcoplasmic proteins were digested/hydrolyzed more easily than myofibrillar proteins. The ex vivo digested myofibrillar and sarcoplasmic duodenal samples showed IC50 values (concentration required to decrease the ACE activity by 50% of 1.06 and 2.16 mg/mL, respectively. The in vitro hydrolyzed myofibrillar and sarcoplasmic samples showed IC50 values of 0.91 and 1.04 mg/mL, respectively. Based on the results of in silico studies, it was possible to identify 9 peptides of the ex vivo hydrolysates and 7 peptides of the in vitro hydrolysates of salmon proteins of 11 selected peptides. In both types of salmon hydrolysates, ACE-inhibitory peptides IW, IY, TVY and VW were identified. In the in vitro salmon protein hydrolysates an ACE-inhibitory peptides VPW and VY were also detected, while ACE-inhibitory peptides ALPHA, IVY and IWHHT were identified in the hydrolysates generated with ex vivo digestion. In our studies, we documented ACE inhibitory in vitro effects of salmon protein hydrolysates obtained by human and as well as porcine gastrointestinal enzymes.

Preschool Inhibitory Control Predicts ADHD Group Status and Inhibitory Weakness in School.

Science.gov (United States)

Jacobson, Lisa A; Schneider, Heather; Mahone, E Mark

2017-12-26

Discriminative utility of performance measures of inhibitory control was examined in preschool children with and without ADHD to determine whether performance measures added to diagnostic prediction and to prediction of informant-rated day-to-day executive function. Children ages 4-5 years (N = 105, 61% boys; 54 ADHD, medication-naïve) were assessed using performance measures (Auditory Continuous Performance Test for Preschoolers-Commission errors, Conflicting Motor Response Test, NEPSY Statue) and caregiver (parent, teacher) ratings of inhibition (Behavior Rating Inventory of Executive Function-Preschool version). Performance measures and parent and teacher reports of inhibitory control significantly and uniquely predicted ADHD group status; however, performance measures did not add to prediction of group status beyond parent reports. Performance measures did significantly predict classroom inhibitory control (teacher ratings), over and above parent reports of inhibitory control. Performance measures of inhibitory control may be adequate predictors of ADHD status and good predictors of young children's classroom inhibitory control, demonstrating utility as components of clinical assessments. © The Author(s) 2017. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Potent Inhibitory Effect of Chinese Dietary Spices on Fatty Acid Synthase.

Science.gov (United States)

Jiang, Bing; Liang, Yan; Sun, Xuebing; Liu, Xiaoxin; Tian, Weixi; Ma, Xiaofeng

2015-09-01

Dietary spices have been adopted in cooking since ancient times to enhance flavor and also as food preservatives and disease remedies. In China, the use of spices and other aromatic plants as food flavoring is an integral part of dietary behavior, but relatively little is known about their functions. Fatty acid synthase (FAS) has been recognized as a remedy target, and its inhibitors might be applied in disease treatment. The present work was designed to assess the inhibitory activities on FAS of spices extracts in Chinese menu. The in vitro inhibitory activities on FAS of 22 extracts of spices were assessed by spectrophotometrically monitoring oxidation of NADPH at 340 nm. Results showed that 20 spices extracts (90.9 %) exhibited inhibitory activities on FAS, with half inhibition concentration (IC(50)) values ranging from 1.72 to 810.7 μg/ml. Among them, seven spices showed strong inhibitory effect with IC(50) values lower than 10 μg/ml. These findings suggest that a large proportion of the dietary spices studied possess promising inhibitory activities on FAS, and subsequently might be applied in the treatment of obesity and obesity-related human diseases.

A virtual screening method for inhibitory peptides of Angiotensin I-converting enzyme.

Science.gov (United States)

Wu, Hongxi; Liu, Yalan; Guo, Mingrong; Xie, Jingli; Jiang, XiaMin

2014-09-01

Natural small peptides from foods have been proven to be efficient inhibitors of Angiotensin I-converting enzyme (ACE) for the regulation of blood pressure. The traditional ACE inhibitory peptides screening method is both time consuming and money costing, to the contrary, virtual screening method by computation can break these limitations. We establish a virtual screening method to obtain ACE inhibitory peptides with the help of Libdock module of Discovery Studio 3.5 software. A significant relationship between Libdock score and experimental IC(50) was found, Libdock score = 10.063 log(1/IC(50)) + 68.08 (R(2) = 0.62). The credibility of the relationship was confirmed by testing the coincidence of the estimated log(1/IC(50)) and measured log(1/IC(50)) (IC(50) is 50% inhibitory concentration toward ACE, in μmol/L) of 5 synthetic ACE inhibitory peptides, which was virtual hydrolyzed and screened from a kind of seafood, Phascolosoma esculenta. Accordingly, Libdock method is a valid IC(50) estimation tool and virtual screening method for small ACE inhibitory peptides. © 2014 Institute of Food Technologists®

Determination of the minimum inhibitory concentration (MIC and mutant prevention concentration (MPC of selected antimicrobials in bovine and swine Pasteurella multocida, Escherichia coli, and Staphylococcus aureus isolates

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Kateřina Nedbalcová

2015-01-01

Full Text Available We compared the values of the minimum inhibitory concentration (MIC and mutant prevention concentration (MPC values ​​of three antimicrobial agents for 72 bovine isolates of Pasteurella multocida, 80 swine isolates of P. multocida, 80 bovine isolates of Escherichia coli, 80 swine isolates of E. coli, and 80 isolates of Staphylococcus aureus from bovine mastitis. The ratio of MIC90​​/MPC90 which limited mutant selection window (MSW was ≤ 0.12/4 mg/l for enrofloxacin, 0.5/≥ 64 mg/l for florfenicol and 4/≥ 128 mg/l for tulathromycin in bovine P. multocida isolates, ≤ 0.12/2 mg/l for enrofloxacin, 0.5/≥ 64 mg/l for florfenicol and 4/≥ 128 mg/l for tulathromycin in swine P. multocida isolates, 1/16 mg/l for enrofloxacin, 8/≥ 64 mg/l for florfenicol and 8/≥ 128 mg/l for tulathromycin in bovine E. coli isolates, 0.5/16 mg/l for enrofloxacin, ≥ 64/≥ 64 mg/l for florfenicol and 8/≥ 128 mg/l for tulathromycin in swine E. coli isolates, and 0.25/16 mg/l for enrofloxacin, 4/≥ 64 mg/l for florfenicol and 4/≥ 128 mg/l for tulathromycin in S. aureus isolates. These findings indicate that the dosage of antimicrobial agents to achieve serum concentration equal to or higher than MPC could reduce selection of resistant bacterial subpopulation.

Inhibitory effect of high NH4(+)-N concentration on anaerobic biotreatment of fresh leachate from a municipal solid waste incineration plant.

Science.gov (United States)

Liu, Zhao; Dang, Yan; Li, Caihua; Sun, Dezhi

2015-09-01

Fresh leachate from municipal solid waste (MSW) incineration plants generally contains extremely high NH4(+)-N concentration which could inhibit the bioactivity of microorganisms. The inhibitory effect of high NH4(+)-N concentration on anaerobic biotreatment of fresh leachate from a MSW incineration plant in China has been investigated in this study. The inhibition processes was studied by both static tests and a laboratory-scale expanded granular sludge bed (EGSB) reactor. The specific methanogenic activity (SMA) of the microorganisms in anaerobic granular sludge was inhibited with the NH4(+)-N concentration increasing to 1000mg/L in static tests. As well the chemical oxygen demand (COD) removal efficiency and the methane yield decreased in the EGSB reactor, while the volatile fatty acids (VFAs) accumulated and extracellular polymeric substances (EPS) of the anaerobic granular sludge increased with NH4(+)-N concentration rising to 1000mg/L, without any rebounding during 30days of operation. Decreasing NH4(+)-N concentration to 500mg/L in influent, the COD removal efficiency recovered to about 85% after 26days. 1000mg/L of NH4(+)-N in leachate was suggested to be the inhibition threshold in EGSB reactor. High-throughput sequencing results showed little changes in microbial communities of the sludge for a high NH4(+)-N concentration, indicating that the survival of most microorganisms was not affected under such a condition. It inhibited the bioactivity of the microorganisms, resulting in decrease of the COD removal efficiency. Copyright © 2015 Elsevier Ltd. All rights reserved.

When is an Inhibitory Synapse Effective?

Science.gov (United States)

Qian, Ning; Sejnowski, Terrence J.

1990-10-01

Interactions between excitatory and inhibitory synaptic inputs on dendrites determine the level of activity in neurons. Models based on the cable equation predict that silent shunting inhibition can strongly veto the effect of an excitatory input. The cable model assumes that ionic concentrations do not change during the electrical activity, which may not be a valid assumption, especially for small structures such as dendritic spines. We present here an analysis and computer simulations to show that for large Cl^- conductance changes, the more general Nernst-Planck electrodiffusion model predicts that shunting inhibition on spines should be much less effective than that predicted by the cable model. This is a consequence of the large changes in the intracellular ionic concentration of Cl^- that can occur in small structures, which would alter the reversal potential and reduce the driving force for Cl^-. Shunting inhibition should therefore not be effective on spines, but it could be significantly more effective on the dendritic shaft at the base of the spine. In contrast to shunting inhibition, hyperpolarizing synaptic inhibition mediated by K^+ currents can be very effective in reducing the excitatory synaptic potentials on the same spine if the excitatory conductance change is less than 10 nS. We predict that if the inhibitory synapses found on cortical spines are to be effective, then they should be mediated by K^+ through GABA_B receptors.

Decision and Inhibitory Trees for Decision Tables with Many-Valued Decisions

KAUST Repository

Azad, Mohammad

2018-06-06

Decision trees are one of the most commonly used tools in decision analysis, knowledge representation, machine learning, etc., for its simplicity and interpretability. We consider an extension of dynamic programming approach to process the whole set of decision trees for the given decision table which was previously only attainable by brute-force algorithms. We study decision tables with many-valued decisions (each row may contain multiple decisions) because they are more reasonable models of data in many cases. To address this problem in a broad sense, we consider not only decision trees but also inhibitory trees where terminal nodes are labeled with “̸= decision”. Inhibitory trees can sometimes describe more knowledge from datasets than decision trees. As for cost functions, we consider depth or average depth to minimize time complexity of trees, and the number of nodes or the number of the terminal, or nonterminal nodes to minimize the space complexity of trees. We investigate the multi-stage optimization of trees relative to some cost functions, and also the possibility to describe the whole set of strictly optimal trees. Furthermore, we study the bi-criteria optimization cost vs. cost and cost vs. uncertainty for decision trees, and cost vs. cost and cost vs. completeness for inhibitory trees. The most interesting application of the developed technique is the creation of multi-pruning and restricted multi-pruning approaches which are useful for knowledge representation and prediction. The experimental results show that decision trees constructed by these approaches can often outperform the decision trees constructed by the CART algorithm. Another application includes the comparison of 12 greedy heuristics for single- and bi-criteria optimization (cost vs. cost) of trees. We also study the three approaches (decision tables with many-valued decisions, decision tables with most common decisions, and decision tables with generalized decisions) to handle

Inhibitory effects of silver zeolite on in vitro growth of fish egg pathogen, Saprolegnia sp.

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Seyed Ali Johari

2014-05-01

Full Text Available Objective: To investigate the effects of powdered silver zeolite (SZ on the in vitro growth of the fish pathogen Saprolegnia sp. Methods: The antifungal activity of SZ was evaluated by determining the minimum inhibitory concentrations using two-fold serial dilutions of powdered SZ in a glucose yeast extract agar at 22 °C. The growth of Saprolegnia sp. on the SZ agar treatments was compared to that on SZ-free agar controls. Results: The results showed that SZ had an inhibitory effect on the in vitro growth of the tested fungi. The minimum inhibitory concentration of SZ for Saprolegnia sp. was also calculated at 600 mg/L, which is equal to 0.06 percent. Conclusions: SZ is a potential good candidate to replace teratogenic and toxic agents, such as malachite green in aquaculture systems.

In vitro assay of the inhibitory effect of neem callus and leaf extracts on some phytopathogenes

International Nuclear Information System (INIS)

El Gaali, E.; Mukhtar, I.

2006-01-01

The effect of different concentrations of neem (Azadirachta indica) callus and leaf extracts on the radial growth of drechslera rostrata, fusarium oxysporum and alterneria alternata was assessed. Obvious inhibitory effect was observed on the mycelia radial growth of the three treated fungi. The level of inhibition increased with the increase of the extract concentration. The maximum inhibitory effect (84%) was recorded with drechslera rostrata when inoculated in media containing 20 mg/ml of neem callus extract, while the inhibition rate of the mycelial growth of the same species reached 61% when inoculated in a medium containing the same concentration of neem leaf extract. The subsequent concentrations of the callus and leaf extracts gave similar trends of inhibition on the fungi cultured on extract amended agar plates. (Author)

In vitro activity of mecillinam against anaerobic bacteria.

OpenAIRE

Steinkraus, G E; McCarthy, L R

1980-01-01

A microtiter broth dilution method was employed to determine the in vitro activity of mecillinam against 201 recent clinical isolates of anaerobic bacteria. Both the anerobic gram-positive and anaerobic gram-negative bacilli displayed a wide range of minimal inhibitory concentrations of mecillinam; most strains were resistant to the antibiotic. The anaerobic cocci exhibited a narrower range of minimal inhibitory concentrations than were observed with other anaerobes, but also exhibited mecill...

Therapeutic effect of Lianbeijuqin (a Chinese herbal cocktail) on ...

African Journals Online (AJOL)

Additionally, the antibacterial activity of LBJQ against Porphyromonas gingivalis, Prevotella intermedius, Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, Streptococcus sanguis and Streptococcus mutans were evaluated using minimal inhibitory concentration (MIC) and minimal bactericidal concentration ...

A self-loading microfluidic device for determining the minimum inhibitory concentration of antibiotics.

Science.gov (United States)

Cira, Nate J; Ho, Jack Y; Dueck, Megan E; Weibel, Douglas B

2012-03-21

This article describes a portable microfluidic technology for determining the minimum inhibitory concentration (MIC) of antibiotics against bacteria. The microfluidic platform consists of a set of chambers molded in poly(dimethylsiloxane) (PDMS) that are preloaded with antibiotic, dried, and reversibly sealed to a second layer of PDMS containing channels that connect the chambers. The assembled device is degassed via vacuum prior to its use, and the absorption of gas by PDMS provides the mechanism for actuating and metering the flow of fluid in the microfluidic channels and chambers. During the operation of the device, degas driven flow introduces a suspension of bacterial cells, dissolves the antibiotic, and isolates cells in individual chambers without cross contamination. The growth of bacteria in the chambers in the presence of a pH indicator produces a colorimetric change that can be detected visually using ambient light. Using this device we measured the MIC of vancomycin, tetracycline, and kanamycin against Enterococcus faecalis 1131, Proteus mirabilis HI4320, Klebsiella pneumoniae, and Escherichia coli MG1655 and report values that are comparable to standard liquid broth dilution measurements. The device provides a simple method for MIC determination of individual antibiotics against human pathogens that will have applications for clinical and point-of-care medicine. Importantly, this device is designed around simplicity: it requires a single pipetting step to introduce the sample, no additional components or external equipment for its operation, and provides a straightforward visual measurement of cell growth. As the device introduces a novel approach for filling and isolating dead-end microfluidic chambers that does not require valves and actuators, this technology should find applications in other portable assays and devices.

COX-1 inhibitory effect of medicinal plants of Ghana

DEFF Research Database (Denmark)

Larsen, Birgitte HV; Soelberg, Jens; Jäger, Anna

2015-01-01

zanthoxyloides showed an inhibitory effect over 90% in the final concentration 0.1 μg/μL. The HPLC profiles indicated that the extracts of the four active species did not contain tannins. The observed in vitro activities support the use of some of the plant species in the traditional medicine system in Ghana....

Purification of Angiotensin Converting Enzyme Inhibitory Peptide Derived From Kacang Goat Meat Protein Hydrolysate

OpenAIRE

Jamhari, J; Yusiati, L.M; Suryanto, E; Cahyanto, M.N; Erwanto, Y; Muguruma, M

2013-01-01

The objective of this study was to identify the Angiotensin Converting Enzyme (ACE) inhibitorypeptide derived from Kacang goat meat protein hydrolysate. Kacang goat meat loin section washydrolyzed with pepsin, trypsin and chymotrypsin. Protein hydrolysate of Kacang goat meat was thentested the protein concentration and ACE inhibitory activity. ACE inhibitory peptide of the proteinhydrolysate was purified through several steps of purification by column SEP-PAK Plus C18 Cartridgeand RP-HPLC usi...

Control of Aspergillus niger with garlic, onion and leek extracts | Irkin ...

African Journals Online (AJOL)

Allium cepa L.) and leek (Allium porrum L.) were investigated against Aspergillus niger. Minimal inhibitory concentrations (MIC) and minimal fungicidal concentrations (MFC) of aqueous, ethyl alcohol and acetone extracts were determined by ...

The Inhibitory Effect of Prunella vulgaris L. on Aldose Reductase and Protein Glycation

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Hong Mei Li

2012-01-01

Full Text Available To evaluate the aldose reductase (AR enzyme inhibitory ability of Prunella vulgaris L. extract, six compounds were isolated and tested for their effects. The components were subjected to in vitro bioassays to investigate their inhibitory assays using rat lens aldose reductase (rAR and human recombinant AR (rhAR. Among them, caffeic acid ethylene ester showed the potent inhibition, with the IC50 values of rAR and rhAR at 3.2±0.55 μM and 12.58±0.32 μM, respectively. In the kinetic analyses using Lineweaver-Burk plots of 1/velocity and 1/concentration of substrate, this compound showed noncompetitive inhibition against rhAR. Furthermore, it inhibited galactitol formation in a rat lens incubated with a high concentration of galactose. Also it has antioxidative as well as advanced glycation end products (AGEs inhibitory effects. As a result, this compound could be offered as a leading compound for further study as a new natural products drug for diabetic complications.

Streptomyces lunalinharesii 235 prevents the formation of a sulfate-reducing bacterial biofilm

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Juliana Pacheco da Rosa

Full Text Available ABSTRACT Streptomyces lunalinharesii strain 235 produces an antimicrobial substance that is active against sulfate reducing bacteria, the major bacterial group responsible for biofilm formation and biocorrosion in petroleum reservoirs. The use of this antimicrobial substance for sulfate reducing bacteria control is therefore a promising alternative to chemical biocides. In this study the antimicrobial substance did not interfere with the biofilm stability, but the sulfate reducing bacteria biofilm formation was six-fold smaller in carbon steel coupons treated with the antimicrobial substance when compared to the untreated control. A reduction in the most probable number counts of planktonic cells of sulfate reducing bacteria was observed after treatments with the sub-minimal inhibitory concentration, minimal inhibitory concentration, and supra-minimal inhibitory concentration of the antimicrobial substance. Additionally, when the treated coupons were analyzed by scanning electron microscopy, the biofilm formation was found to be substantially reduced when the supra-minimal inhibitory concentration of the antimicrobial substance was used. The coupons used for the biofilm formation had a small weight loss after antimicrobial substance treatment, but corrosion damage was not observed by scanning electron microscopy. The absence of the dsrA gene fragment in the scraped cell suspension after treatment with the supra-minimal inhibitory concentration of the antimicrobial substance suggests that Desulfovibrio alaskensis was not able to adhere to the coupons. This is the first report on an antimicrobial substance produced by Streptomyces active against sulfate reducing bacteria biofilm formation. The application of antimicrobial substance as a potential biocide for sulfate reducing bacteria growth control could be of great interest to the petroleum industry.

Minimal lethal concentration of hyrgromycin B in calli induction and shoot multiplication process of Digitalis purpurea L.

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Elizabeth Kairúz Hernández-Díaz

2013-01-01

Full Text Available The plants of the genus Digitalis are characterized by the production of cardenolides, drugs widely used worldwide in the treatment of heart failure. In previous research a transformation protocol was developed from leaf disc of Digitalis purpurea L., using geneticin as selection marker. However some escapes in the selection process were obtained. So it is necessary to develop a more efficient selection scheme using another selective agent. Therefore, the aim of the present research was to select the minimum lethal concentration of hygromycin B during callus induction and shoots multiplication of D. purpurea. For callus induction we studied five concentrations of hygromycine B (3, 6, 9, 12, 15 mg l-1 during 28 days. Besides, the effect in shoot multiplication of four concentrations of hygromycine B (25, 50, 75, 100 mg l-1 was studied during 30 days. The minimal lethal concentration for callus formation was 12 mg l-1. In the case of shoot multiplication, 100% mortality was showed at 75 mg l-1 strictly after 30 days. The proposed selection scheme is recommended for future work at genetic transformation in this species. Keywords: cardenolides, genetic transformation, hpt, selection

Whole Genome Sequence Analysis of Pig Respiratory Bacterial Pathogens with Elevated Minimum Inhibitory Concentrations for Macrolides.

Science.gov (United States)

Dayao, Denise Ann Estarez; Seddon, Jennifer M; Gibson, Justine S; Blackall, Patrick J; Turni, Conny

2016-10-01

Macrolides are often used to treat and control bacterial pathogens causing respiratory disease in pigs. This study analyzed the whole genome sequences of one clinical isolate of Actinobacillus pleuropneumoniae, Haemophilus parasuis, Pasteurella multocida, and Bordetella bronchiseptica, all isolated from Australian pigs to identify the mechanism underlying the elevated minimum inhibitory concentrations (MICs) for erythromycin, tilmicosin, or tulathromycin. The H. parasuis assembled genome had a nucleotide transition at position 2059 (A to G) in the six copies of the 23S rRNA gene. This mutation has previously been associated with macrolide resistance but this is the first reported mechanism associated with elevated macrolide MICs in H. parasuis. There was no known macrolide resistance mechanism identified in the other three bacterial genomes. However, strA and sul2, aminoglycoside and sulfonamide resistance genes, respectively, were detected in one contiguous sequence (contig 1) of A. pleuropneumoniae assembled genome. This contig was identical to plasmids previously identified in Pasteurellaceae. This study has provided one possible explanation of elevated MICs to macrolides in H. parasuis. Further studies are necessary to clarify the mechanism causing the unexplained macrolide resistance in other Australian pig respiratory pathogens including the role of efflux systems, which were detected in all analyzed genomes.

An anti-steroidogenic inhibitory primer pheromone in male sea lamprey (Petromyzon marinus)

Science.gov (United States)

Chung-Davidson, Yu-Wen; Wang, Huiyong; Bryan, Mara B.; Wu, Hong; Johnson, Nicholas S.; Li, Weiming

2013-01-01

Reproductive functions can be modulated by both stimulatory and inhibitory primer pheromones released by conspecifics. Many stimulatory primer pheromones have been documented, but relatively few inhibitory primer pheromones have been reported in vertebrates. The sea lamprey male sex pheromone system presents an advantageous model to explore the stimulatory and inhibitory primer pheromone functions in vertebrates since several pheromone components have been identified. We hypothesized that a candidate sex pheromone component, 7α, 12α-dihydroxy-5α-cholan-3-one-24-oic acid (3 keto-allocholic acid or 3kACA), exerts priming effects through the hypothalamic-pituitary-gonadal (HPG) axis. To test this hypothesis, we measured the peptide concentrations and gene expressions of lamprey gonadotropin releasing hormones (lGnRH) and the HPG output in immature male sea lamprey exposed to waterborne 3kACA. Exposure to waterborne 3kACA altered neuronal activation markers such as jun and jun N-terminal kinase (JNK), and lGnRH mRNA levels in the brain. Waterborne 3kACA also increased lGnRH-III, but not lGnRH-I or -II, in the forebrain. In the plasma, 3kACA exposure decreased all three lGnRH peptide concentrations after 1 h exposure. After 2 h exposure, 3kACA increased lGnRHI and -III, but decreased lGnRH-II peptide concentrations in the plasma. Plasma lGnRH peptide concentrations showed differential phasic patterns. Group housing condition appeared to increase the averaged plasma lGnRH levels in male sea lamprey compared to isolated males. Interestingly, 15α-hydroxyprogesterone (15α-P) concentrations decreased after prolonged 3kACA exposure (at least 24 h). To our knowledge, this is the only known synthetic vertebrate pheromone component that inhibits steroidogenesis in males.

ANTIBACTERIAL PROPERTIES OF PHARMACEUTICAL COMPOSITION OF HEPATOPROTECTORS

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Aslanian MA

2016-12-01

Full Text Available Pathology problemof hepatobiliary system (HBS of contagious origin becomes relevant with the increase of disturbance and complications of lipid metabolism and bile pigments among young people. Leading role in prophylaxis and treatment in the context of this pathology belongs to antibacterialc hemotherapeutic agents. However, along with antimicrobial activity, numerous side effects can be observed during treatment with antibacterial agents. According to the recent study on hepatobiliary system (HBS, therapeutic effect can be seen only while using herbal medicine with choleretic action as well as their various compositions.Amountof medicine with the appropriate effect is insufficient, that is why the study was conducted towards finding effective combinations of plant substances of different groups for the purpose of creatingan effective medicine for treatment of hepatobiliary system (HBS of contagious origin. Aim of the work The purpose of study was to examine antibacterial properties of different combinations with flamin and lavender oil in combined medicine during the course of treatment of cholecystitis and cholangitis. Materials and methods. It the result of study 61 microbial strains were distinguished and identified from the pathological material taken from 53 patients with cholecystitis and cholangitis. All distinguished clinical microbial strains taken from the patients were tested for sensitivity to combined medicine in the form of tablets with flamin and lavender oil. Minimal inhibitory concentration for S. aureus АТСС 25923 amounted to 250-350 ug/ml, for E. coli АТСС 25922 - 350±50,0 ug/ml, for P. aeruginosa АТСС 27853 750±100,0 ug/ml, for Р. vulgaris АТСС 4636 - 850±100,0 ug/ml, minimal inhibitory concentration to the tablets № 2 та № 3 amounted to > 1000 мкг/мл. Minimal inhibitory concentration for B. subtilis АТСС 6633 amounted to 250±50,0 ug/ml, for C. albicans ATCC 885/653 300±50,0 ug

The inhibitory effect of bovine rumen fluid on Salmonella typhimurium.

Science.gov (United States)

Chambers, P G; Lysons, R J

1979-05-01

The possible fate of Salmonella typhimurium in the rumen was investigated by monitoring rumen volatile fatty acids (VFA), lactate concentrations and pH over periods which included regular feeding and 48 h starvation. Preparations were made containing 50 per cent rumen fluid from the cow or VFA solutions, and then inoculated with S typhimurium. Viable counts before and after incubation for 24 h at 37 degrees C were compared. Incubation in broths with high concentrations of VFA and low pH resulted in a marked decrease in salmonella numbers, while lower VFA concentrations had little or no inhibitory effect on growth.

Assessment of methods to determine minimal cellulase concentrations for efficient hydrolysis of cellulose

Energy Technology Data Exchange (ETDEWEB)

Hogan, C.M.; Mes-Hartree, M.; Saddler, J.N. (Forintek Canada Corp., Ottawa, ON (Canada). Biotechnology and Chemistry Dept.); Kushner, D.J. (Toronto Univ., Ontario (Canada). Dept. of Microbiology)

1990-02-01

The enzyme loading needed to achieve substrate saturation appeared to be the most economical enzyme concentration to use for hydrolysis, based on percentage hydrolysis. Saturation was reached at 25 filter paper units per gram substrate on Solka Floc BW300, as determined by studying (a) initial adsorption of the cellulase preparation onto the substrate, (b) an actual hydrolysis or (c) a combined hydrolysis and fermentation (CHF) process. Initial adsorption of the cellulases onto the substrate can be used to determine the minimal cellulase requirements for efficient hydrolysis since enzymes initially adsorbed to the substrate have a strong role in governing the overall reaction. Trichoderma harzianum E58 produces high levels of {beta}-glucosidase and is able to cause high conversion of Solka Floc BW300 to glucose without the need for exogenous {beta}-glucosidase. End-product inhibition of the cellulase and {beta}-glucosidase can be more effectively reduced by employing a CHF process than by supplemental {beta}-glucosidase. (orig.).

The Diversity of Cortical Inhibitory Synapses

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Yoshiyuki eKubota

2016-04-01

Full Text Available The most typical and well known inhibitory action in the cortical microcircuit is a strong inhibition on the target neuron by axo-somatic synapses. However, it has become clear that synaptic inhibition in the cortex is much more diverse and complicated. Firstly, at least ten or more inhibitory non-pyramidal cell subtypes engage in diverse inhibitory functions to produce the elaborate activity characteristic of the different cortical states. Each distinct non-pyramidal cell subtype has its own independent inhibitory function. Secondly, the inhibitory synapses innervate different neuronal domains, such as axons, spines, dendrites and soma, and their IPSP size is not uniform. Thus cortical inhibition is highly complex, with a wide variety of anatomical and physiological modes. Moreover, the functional significance of the various inhibitory synapse innervation styles and their unique structural dynamic behaviors differ from those of excitatory synapses. In this review, we summarize our current understanding of the inhibitory mechanisms of the cortical microcircuit.

An experimental study on the inhibitory effect of high concentration bicarbonate on the reduction of U(VI) in groundwater by functionalized indigenous microbial communities

International Nuclear Information System (INIS)

Dianxin Li; Nan Hu; Dexin Ding; Shimi Li; Guangyue Li; Yongdong Wang

2016-01-01

The anaerobic microcosms amended with 30 mM bicarbonate and without bicarbonate were established, respectively, and the reduction of U(VI) in the microcosms by functionalized indigenous microbial communities was investigated. Results of the chemical extraction and XANES analysis showed that the proportions of U(IV) in the microcosms amended with bicarbonate were 10 % lower than without bicarbonate at day 46. The amount of Cellulomonadaceae, Desulfovibrionaceae, Peptococcaceae and Veillonellaceae amended with bicarbonate was lower than without bicarbonate, so the reduction of U(VI) was less. The experimental results show that the high concentration bicarbonate has a significantly inhibitory effect on the reduction of U(VI). (author)

Inhibitory effects of flavonoids on biofilm formation by Staphylococcus aureus that overexpresses efflux protein genes.

Science.gov (United States)

Lopes, Laênia Angélica Andrade; Dos Santos Rodrigues, Jéssica Bezerra; Magnani, Marciane; de Souza, Evandro Leite; de Siqueira-Júnior, José P

2017-06-01

This study evaluated the efficacy of glycone (myricitrin, hesperidin and phloridzin) and aglycone flavonoids (myricetin, hesperetin and phloretin) in inhibiting biofilm formation by Staphylococcus aureus RN4220 and S. aureus SA1199B that overexpress the msrA and norA efflux protein genes, respectively. The minimum inhibitory concentration (MIC) and minimum biofilm inhibitory concentration (MBIC 50 - defined as the lowest concentration that resulted in ≥50% inhibition of biofilm formation) of flavonoids were determined using microdilution in broth procedures. The flavonoids showed MIC >1024 μg/mL against S. aureus RN4220 and S. aureus SA1199B; however, these compounds at lower concentrations (1-256 μg/mL) showed inhibitory effects on biofilm formation by these strains. Aglycone flavonoids showed lower MBIC 50 values than their respective glycone forms. The lowest MBIC 50 values (1 and 4 μg/mL) were observed against S. aureus RN4220. Myricetin, hesperetin and phloretin exhibited biofilm formation inhibition >70% for S. aureus RN4220, and lower biofilm formation inhibition against S. aureus SA1199B. These results indicate that sub-MICs of the tested flavonoids inhibit biofilm formation by S. aureus strains that overexpress efflux protein genes. These effects are more strongly established by aglycone flavonoids. Copyright © 2017 Elsevier Ltd. All rights reserved.

A procedure to compute equilibrium concentrations in multicomponent systems by Gibbs energy minimization on spreadsheets

International Nuclear Information System (INIS)

Lima da Silva, Aline; Heck, Nestor Cesar

2003-01-01

Equilibrium concentrations are traditionally calculated with the help of equilibrium constant equations from selected reactions. This procedure, however, is only useful for simpler problems. Analysis of the equilibrium state in a multicomponent and multiphase system necessarily involves solution of several simultaneous equations, and, as the number of system components grows, the required computation becomes more complex and tedious. A more direct and general method for solving the problem is the direct minimization of the Gibbs energy function. The solution for the nonlinear problem consists in minimizing the objective function (Gibbs energy of the system) subjected to the constraints of the elemental mass-balance. To solve it, usually a computer code is developed, which requires considerable testing and debugging efforts. In this work, a simple method to predict equilibrium composition in multicomponent systems is presented, which makes use of an electronic spreadsheet. The ability to carry out these calculations within a spreadsheet environment shows several advantages. First, spreadsheets are available 'universally' on nearly all personal computers. Second, the input and output capabilities of spreadsheets can be effectively used to monitor calculated results. Third, no additional systems or programs need to be learned. In this way, spreadsheets can be as suitable in computing equilibrium concentrations as well as to be used as teaching and learning aids. This work describes, therefore, the use of the Solver tool, contained in the Microsoft Excel spreadsheet package, on computing equilibrium concentrations in a multicomponent system, by the method of direct Gibbs energy minimization. The four phases Fe-Cr-O-C-Ni system is used as an example to illustrate the method proposed. The pure stoichiometric phases considered in equilibrium calculations are: Cr 2 O 3 (s) and FeO C r 2 O 3 (s). The atmosphere consists of O 2 , CO e CO 2 constituents. The liquid iron

Comparison of Heuristics for Inhibitory Rule Optimization

KAUST Repository

Alsolami, Fawaz; Chikalov, Igor; Moshkov, Mikhail

2014-01-01

Friedman test with Nemenyi post-hoc are used to compare the greedy algorithms statistically against each other for length and coverage. The experiments are carried out on real datasets from UCI Machine Learning Repository. For leading heuristics, the constructed rules are compared with optimal ones obtained based on dynamic programming approach. The results seem to be promising for the best heuristics: the average relative difference between length (coverage) of constructed and optimal rules is at most 2.27% (7%, respectively). Furthermore, the quality of classifiers based on sets of inhibitory rules constructed by the considered heuristics are compared against each other, and the results show that the three best heuristics from the point of view classification accuracy coincides with the three well-performed heuristics from the point of view of rule length minimization.

Biodegradation of indole at high concentration by persolvent fermentation with Pseudomonas sp. ST-200.

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Doukyu, N; Aono, R

1997-05-01

Pseudomonas sp. strain ST-200 grew on indole as a sole carbon source. The minimal inhibitory concentration of indole was 0.3 mg/ml for ST-200. However, ST-200 grew in a persolvent fermentation system containing a large amount of indole (a medium containing 20% by vol. diphenylmethane and 4 mg/ml indole), because most of the indole was partitioned in the organic solvent layer. When the organism was grown in the medium containing indole at 1 mg/ml in the presence of diphenylmethane, more than 98% of the indole was consumed after 48h. Isatic acid (0.4 mg/ml) and isatin (0.03 mg/ml) were produced as the metabolites in the aqueous medium layer.

Inhibitory effect of celecoxib on agomelatine metabolism in vitro and in vivo

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He JY

2018-03-01

Full Text Available Jiayang He,1 Ping Fang,2 Xiang Zheng,2 Chenchen Wang,2 Tenghui Liu,2 Bowen Zhang,2 Jian Wen,2 Ren-ai Xu3 1Department of Pharmacy, The First Hospital of Jiaxing, Jiaxing, Zhejiang, China; 2Department of Pharmacology, School of Pharmacy of Wenzhou Medical University, Wenzhou, Zhejiang, China; 3Department of Pharmacy, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China Aim: The aim of this study was to study the effect of celecoxib on agomelatine metabolism in vitro and in vivo. Methods: Ten healthy male Sprague–Dawley rats were randomly divided into 2 groups: Group A (control group and Group B (30 mg/kg celecoxib. Then a single dose of 20 mg/kg agomelatine was administered orally 30 min after administration of celecoxib. In an in vitro study, celecoxib with a series of concentrations was added to an incubation mixture containing recombinant human CYP2C9, human or rat liver microsomes to determine the half-maximal inhibitory concentration on the metabolism of agomelatine. Moreover, a mechanism study was performed to determine the inhibitory effect of celecoxib on CYP2C9. Results: The results showed that a single dose of 30 mg/kg celecoxib significantly increased the area under the concentration-time curve and maximum concentration of agomelatine. In addition, celecoxib inhibited the metabolism of agomelatine in the in vitro studies, which was determined to be by a competitive mechanism on CYP2C9. Those results indicated that celecoxib has an inhibitory effect on the metabolism of agomelatine both in vivo and in vitro. Conclusion: Thus, more attention should be paid when celecoxib is administered combined with agomelatine. Keywords: agomelatine, liver microsomes, pharmacokinetics, celecoxib, CYP2C9

Spectroscopic Characterization of Extracellular Polymeric Substances from Escherichia coli and Serratia marcescens: Suppression using Sub-Inhibitory Concentrations of Bismuth Thiols

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Badireddy, Appala R.; Korpol, Bhoom Reddy; Chellam, Shankararaman; Gassman, Paul L.; Engelhard, Mark H.; Lea, Alan S.; Rosso, Kevin M.

2008-10-21

Free and capsular EPS produced by Escherichia coli and Serratia marcescens were characterized in detail using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and Auger electron spectroscopy (AES). Total EPS production decreased upon treatment with sub-inhibitory concentrations of lipophilic bismuth thiols (bismuth dimercaptopropanol, BisBAL; bismuth ethanedithiol, BisEDT; and bismuth pyrithione, BisPYR), BisBAL being most effective. Bismuth thiols also influenced acetylation and carboxylation of polysaccharides in EPS from S. marcescens. Extensive homology between EPS samples in the presence and absence of bismuth was observed with proteins, polysaccharides, and nucleic acids varying predominantly only in the total amount expressed. Second derivative analysis of the amide I region of FTIR spectra revealed decreases in protein secondary structures in the presence of bismuth thiols. Hence, anti-fouling properties of bismuth thiols appear to originate in their ability to suppress O-acetylation and protein secondary structures in addition to total EPS secretion.

Monoamine oxidase inhibitory activity in tobacco particulate matter: Are harman and norharman the only physiologically relevant inhibitors?

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Truman, Penelope; Grounds, Peter; Brennan, Katharine A

2017-03-01

Monoamine oxidase inhibition is significant in smokers, but it is still unclear how the inhibition that is seen in the brains and bodies of smokers is brought about. Our aim was to test the contribution of the harman and norharman in tobacco smoke to MAO-A inhibition from tobacco smoke preparations, as part of a re-examination of harman and norharman as the cause of the inhibition of MAO-A inhibition in the brain. Tobacco smoke particulate matter and cigarette smoke particulate matter were prepared and the amounts of harman and norharman measured. The results were compared with the total monoamine oxidase-A inhibitory activity. At a nicotine concentration of 0.6μM (a "physiological" concentration in blood) the total monoamine oxidase-A inhibitory activity measured in these samples was sufficient to inhibit the enzyme by approximately 10%. Of this inhibitory activity, only a small proportion of the total was found to be due to harman and norharman. These results show that harman and norharman provide only a moderate contribution to the total monoamine oxidase-A inhibitory activity of tobacco smoke, perhaps under 10%. This suggests that other inhibitors (either known or unknown) may be more significant contributors to total inhibitory activity than has yet been established, and deserve closer examination. Copyright © 2017 Elsevier B.V. All rights reserved.

Kinetics of α-amylase and α-glucosidase inhibitory potential of Zea mays Linnaeus (Poaceae), Stigma maydis aqueous extract: An in vitro assessment.

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Sabiu, S; O'Neill, F H; Ashafa, A O T

2016-05-13

Corn silk (Zea mays L., Stigma maydis) is an important herb used traditionally in many parts of the world to treat array of diseases including diabetes mellitus. Inhibitors of α-amylase and α-glucosidase offer an effective strategy to modulate levels of post prandial hyperglycaemia via control of starch metabolism. This study evaluated α-amylase and α-glucosidase inhibitory potentials of corn silk aqueous extract. Active principles and antioxidant attributes of the extract were also analysed. The α-amylase inhibitory potential of the extract was investigated by reacting its different concentrations with α-amylase and starch solution, while α-glucosidase inhibition was determined by pre-incubating α-glucosidase with different concentrations of the extract followed by addition of p-nitrophenylglucopyranoside. The mode(s) of inhibition of the enzymes were determined using Lineweaver-Burke plot. In vitro analysis of the extract showed that it exhibited potent and moderate inhibitory potential against α-amylase and α-glucosidase, respectively. The inhibition was concentration-dependent with respective half-maximal inhibitory concentration (IC50) values of 5.89 and 0.93mg/mL. Phytochemical analyses revealed the presence of alkaloids, flavonoids, phenols, saponins, tannins and phytosterols as probable inhibitory constituents. Furthermore, the extract remarkably scavenges reactive oxygen species like DPPH and nitric oxide radicals, elicited good reducing power and a significant metal chelating attributes. Overall, the non-competitive and uncompetitive mechanism of action of corn silk extract is due to its inhibitory effects on α-amylase and α-glucosidase, respectively. Consequently, this will reduce the rate of starch hydrolysis, enhance palliated glucose levels, and thus, lending credence to hypoglycaemic candidature of corn silk. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Identification of novel dipeptidyl peptidase IV (DPP-IV) inhibitory peptides in camel milk protein hydrolysates.

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Nongonierma, Alice B; Paolella, Sara; Mudgil, Priti; Maqsood, Sajid; FitzGerald, Richard J

2018-04-01

Nine novel dipeptidyl peptidase IV (DPP-IV) inhibitory peptides (FLQY, FQLGASPY, ILDKEGIDY, ILELA, LLQLEAIR, LPVP, LQALHQGQIV, MPVQA and SPVVPF) were identified in camel milk proteins hydrolysed with trypsin. This was achieved using a sequential approach combining liquid chromatography tandem mass spectrometry (LC-MS/MS), qualitative/quantitative structure activity relationship (QSAR) and confirmatory studies with synthetic peptides. The most potent camel milk protein-derived DPP-IV inhibitory peptides, LPVP and MPVQA, had DPP-IV half maximal inhibitory concentrations (IC 50 ) of 87.0 ± 3.2 and 93.3 ± 8.0 µM, respectively. DPP-IV inhibitory peptide sequences identified within camel and bovine milk protein hydrolysates generated under the same hydrolysis conditions differ. This was linked to differences in enzyme selectivity for peptide bond cleavage of camel and bovine milk proteins as well as dissimilarities in their amino acid sequences. Camel milk proteins contain novel DPP-IV inhibitory peptides which may play a role in the regulation of glycaemia in humans. Copyright © 2017 Elsevier Ltd. All rights reserved.

Intermixing in heteroepitaxial islands: fast, self-consistent calculation of the concentration profile minimizing the elastic energy

International Nuclear Information System (INIS)

Gatti, R; UhlIk, F; Montalenti, F

2008-01-01

We present a novel computational method for finding the concentration profile which minimizes the elastic energy stored in heteroepitaxial islands. Based on a suitable combination of continuum elasticity theory and configurational Monte Carlo, we show that such profiles can be readily found by a simple, yet fully self-consistent, iterative procedure. We apply the method to SiGe/Si islands, considering realistic three-dimensional shapes (pyramids, domes and barns), finding strongly non-uniform distributions of Si and Ge atoms, in qualitative agreement with several experiments. Moreover, our simulated selective-etching profiles display, in some cases, a remarkable resemblance to the experimental ones, opening intriguing questions on the interplay between kinetic, entropic and elastic effects

Radiometric assessment of the sensitivity to antituberculotics of Mycobacterium avium-intracellulare and Mycobacterium xenopi

International Nuclear Information System (INIS)

Kubin, M.; Lindholm-Levy, P.; Heifets, L. B.

1994-01-01

The macrodilution radiometric method using Middlebrook's 7H12 liquid medium enriched with 14 C-palmitic acid, where the growth activity is monitored by measuring liberated 14 CO 2 , was applied to 25 strains of the Mycobacterium avium complex and to 20 strains of Mycobacterium xenopi to determine the minimal inhibitory concentrations of the following chemotherapeutical agents: ciprofloxacine, clofazimine, rifampin, cycloserine, kanamycin, etionamide, ethambutol, and amikacin. In the case of the M. avium complex, slightly or completely resistant strains were found for the majority of drugs. The sensitive strain proportion was highest with clofazimine and amikacin. The M. xenopis strains exhibited generally lower minimal inhibitory concentrations than the avian mycobacteria for all drugs except for cycloserine and ethambutol. The radiometric method using the BACTEC system was found suitable for the determination of the sensitivity of mycobacteria to chemotherapeutic agents: the results are obtained rapidly, within 8 days following inoculation, and the minimal inhibitory concentrations can be evaluated quantitatively. 1 tab., 8 refs

Mechanisms underlying electrical and mechanical responses of the bovine retractor penis to inhibitory nerve stimulation and to an inhibitory extract.

Science.gov (United States)

Byrne, N. G.; Muir, T. C.

1985-01-01

The response of the bovine retractor penis (BRP) to stimulation of non-adrenergic, non-cholinergic (NANC) inhibitory nerves and to an inhibitory extract prepared from this muscle have been studied using intracellular microelectrode, sucrose gap and conventional mechanical recording techniques. Both inhibitory nerve stimulation and inhibitory extract hyperpolarized the membrane potential and relaxed spontaneous or guanethidine (3 X 10(-5) M)-induced tone. These effects were accompanied by an increase in membrane resistance. Following membrane potential displacement from an average value of -53 +/- 7 mV (n = 184; Byrne & Muir, 1984) inhibitory potentials to nerve stimulation were abolished at approximately -30 mV; there was no evidence of reversal. Displacement by inward hyperpolarizing current over the range -45 to -60 mV increased the inhibitory response to nerve stimulation and to inhibitory extract; at more negative potential values (above approximately -60 mV) the inhibitory potential decreased and was abolished (approximately -103 mV). There was no evidence of reversal. Removal of [K+]o reversibly reduced hyperpolarization to nerve stimulation and inhibitory extract. No enhancement was observed. Increasing the [K+]o to 20 mM reduced the inhibitory potential to nerve stimulation but this was restored by passive membrane hyperpolarization. Inhibitory potentials were obtained at membrane potential values exceeding that of the estimated EK (-49 mV). [Cl-]o-free or [Cl-]o-deficient solutions reduced and abolished (after some 20-25 min) the hyperpolarization produced by inhibitory nerve stimulation or inhibitory extract. The inhibitory potential amplitude following nerve stimulation was not restored by passive displacement of the membrane potential from -26 to -104 mV approximately. Ouabain (1-5 X 10(-5) M) reduced then (45-60 min later) abolished the inhibitory potential to nerve stimulation. The effects of this drug on the extract were not investigated. It is

The effect of minimal concentration of ethylene glycol (EG) combined with polyvinylpyrrolidone (PVP) on mouse oocyte survival and subsequent embryonic development following vitrification.

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Wang, Yao; Okitsu, Osamu; Zhao, Xiao-Ming; Sun, Yun; Di, Wen; Chian, Ri-Cheng

2014-01-01

Vitrification techniques employ a relatively high concentration of cryoprotectant in vitrification solutions. Exposure of oocytes to high concentrations of cryoprotectant is known to damage the oocytes via both cytotoxic and osmotic effects. Therefore, the key to successful vitrification of oocytes is to strike a balance between the usage of minimal concentration of cryoprotectant without compromising their cryoprotective actions. The minimal concentration of ethylene glycol (EG) on mouse oocyte survival and subsequent embryonic development was evaluated following vitrification-warming and parthenogenetic activation. Polyvinylpyrrolidone (PVP) combined with EG on mouse oocyte survival and subsequent embryonic development as well as morphology of the spindle and chromosome alignment were also evaluated. Vitrification system was adapted with JY Straw and the cooling rate was approximately 442-500 °C/min. In contrast, the warming rate was approximately 2,210-2,652 °C/min. Survival rate of oocytes increased significantly when 15 % EG was combined with 2 % PVP in vitrification solution (VS). The effect of combination of EG and PVP was not significant when the concentration of EG was 20 % and higher. Although there were no significant differences in embryonic development, the percentage of abnormal spindle and chromosome alignment was significantly higher in the oocytes without 2 % PVP in VS. Our data provide a proof of principle for oocyte vitrification that may not require a high concentration of cryoprotectant. There are synergic effects of EG combined with PVP for oocyte vitrification, which may provide important information to the field in developing less cytotoxic VS.

Probing inhibitory effects of nanocrystalline cellulose: inhibition versus surface charge

Science.gov (United States)

Male, Keith B.; Leung, Alfred C. W.; Montes, Johnny; Kamen, Amine; Luong, John H. T.

2012-02-01

NCC derived from different biomass sources was probed for its plausible cytotoxicity by electric cell-substrate impedance sensing (ECIS). Two different cell lines, Spodoptera frugiperda Sf9 insect cells and Chinese hamster lung fibroblast V79, were exposed to NCC and their spreading and viability were monitored and quantified by ECIS. Based on the 50%-inhibition concentration (ECIS50), none of the NCC produced was judged to have any significant cytotoxicity on these two cell lines. However, NCC derived from flax exhibited the most pronounced inhibition on Sf9 compared to hemp and cellulose powder. NCCs from flax and hemp pre-treated with pectate lyase were also less inhibitory than NCCs prepared from untreated flax and hemp. Results also suggested a correlation between the inhibitory effect and the carboxylic acid contents on the NCC.

Characterization and partial purification of Candida albicans Secretory IL-12 Inhibitory Factor

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Chandra Jyotsna

2008-02-01

Full Text Available Abstract Background We have previously shown that supernatant from Candida albicans (CA culture contains a Secretory Interleukin (IL-12 Inhibitory Factor (CA-SIIF, which inhibits IL-12 production by human monocytes. However, the effect of CA-SIIF on secretion of other cytokines by monocytes is unknown, and detailed characterization of this factor has not been performed. Results In this study, we demonstrate that the IL-12 inhibitory activity of CA-SIIF was serum-independent, based on the reduction of IL-12 levels in monocytes stimulated under serum-independent conditions. The minimal inhibitory dose of CA-SIIF was found to be 200 μg/ml. Investigation of CA-SIIF's effect on macrophages IL-12 production in vitro and in vivo also showed that CA-SIIF inhibited IL-12 production by murine macrophages both in vitro (from 571 ± 24 pg/ml to 387 ± 87 pg/ml; P = 0.05 and in vivo (from 262 ± 6 pg/ml to 144 ± 30 pg/ml; P P P P Conclusion CA-SIIF is a glycoprotein which exhibits serum-independent inhibition of IL-12 production from monocytes in vitro and in vivo, and also modulates differentiation of monocytes into dendritic cells. These results suggest important role for CA-SIIF in interactions of C. albicans with the host immune system.

Guanylation of thiosemicarbazones: a new synthetic route to polysubstituted guanylhydrazones with antimicrobial activity

International Nuclear Information System (INIS)

Cunha, Silvio; Macedo Junior, Fernando Cesar de; Costa, Giselle A.N.; Neves, Daniela C.; Souza Neta, Lourdes Cardoso de

2009-01-01

Thiosemicarbazones were employed for the first time as electrophiles in the guanylation reaction promoted by HgCl 2 , affording polysubstituted guanylhydrazones, with regioselective introduction of each nitrogen substituent. The antibacterial and antifungal activities of guanylhydrazones were evaluated by determination of minimal inhibitory concentrations. Some of them exhibited very low minimal inhibitory concentrations (MIC) and broad-spectrum activities. The configurations of two guanylhydrazones were assigned by X-ray analysis that also revealed intramolecular interactions of the type N-H...N and C-H...N. (author)

Study on the Antimicrobial activity and Minimum Inhibitory Concentration of Essential Oils of Spices

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R.V.N.Srujan and M.Sravanthi

Full Text Available Antibacterial activity and minimum inhibitory concentration (MIC of essential oils of garlic, clove and cinnamon were estimated by using various bacterial pathogens. Among the bacterial pathogens tested against essential oil of garlic, Staphylococcus aureus was found to be highly sensitive followed by E.coli. L.monocytogenes and S.pyogenes were found to be less sensitive. The essential oil of clove was found to be most active against S.aureus followed by E.coli. B.cereus and C. jejuni. The essential oil of cinnamon was also most active against S.aureus followed by E.coli and C.jejuni. Essential oil of cinnamon was found to be active against all the bacterial pathogens tested, when compared to garlic and clove oils. However Staph. aureus, E. coli and C.jejuni were found to be most sensitive to the action of essential oils of garlic, clove and cinnamon. Among the bacterial pathogens tested against essential oils of spices to know the MIC by agar diffusion method, C.jejuni was found to be most sensitive to the essential oil of garlic followed by E.coli, S. typhimurium and Staphylococcus aureus. L. monocytogenes and Methicillin resistant Staph. aureus were found to be comparatively less sensitive. Essential oil of clove was also found to be highly effective against C.jejuni followed by E.coli, S.typhimurium and S.aureus. Again L.monocytogenes and Methicillin resistant S.aureus were comparatively less sensitive to the action of essential oil of clove. All most all the bacterial pathogens tested were found to be sensitive to the essential oil of cinnamon. However C.jejuni and E.coli were found to be most sensitive followed by S.typhimurium, Staph. aureus and Methicillin resistant Staph. aureus . [Vet. World 2011; 4(7.000: 311-316

Aldose Reductase Inhibitory Activity of Compounds from  Zea mays L.

Science.gov (United States)

Kim, Tae Hyeon; Kim, Jin Kyu; Kang, Young-Hee; Lee, Jae-Yong; Kang, Il Jun; Lim, Soon Sung

2013-01-01

Aldose reductase (AR) inhibitors have a considerable therapeutic potential against diabetes complications and do not increase the risk of hypoglycemia. Through bioassay-guided fractionation of an EtOH extract of the kernel from purple corn (Zea mays L.), 7 nonanthocyanin phenolic compounds (compound 1–7) and 5 anthocyanins (compound 8–12) were isolated. These compounds were investigated by rat lens aldose reductase (RLAR) inhibitory assays. Kinetic analyses of recombinant human aldose reductase (rhAR) were performed, and intracellular galactitol levels were measured. Hirsutrin, one of 12 isolated compounds, showed the most potent RLAR inhibitory activity (IC50, 4.78 μM). In the kinetic analyses using Lineweaver-Burk plots of 1/velocity and 1/substrate concentration, hirsutrin showed competitive inhibition against rhAR. Furthermore, hirsutrin inhibited galactitol formation in rat lens and erythrocytes sample incubated with a high concentration of galactose; this finding indicates that hirsutrin may effectively prevent osmotic stress in hyperglycemia. Therefore, hirsutrin derived from Zea mays L. may be a potential therapeutic agent against diabetes complications. PMID:23586057

Sequentially switching cell assemblies in random inhibitory networks of spiking neurons in the striatum.

Science.gov (United States)

Ponzi, Adam; Wickens, Jeff

2010-04-28

The striatum is composed of GABAergic medium spiny neurons with inhibitory collaterals forming a sparse random asymmetric network and receiving an excitatory glutamatergic cortical projection. Because the inhibitory collaterals are sparse and weak, their role in striatal network dynamics is puzzling. However, here we show by simulation of a striatal inhibitory network model composed of spiking neurons that cells form assemblies that fire in sequential coherent episodes and display complex identity-temporal spiking patterns even when cortical excitation is simply constant or fluctuating noisily. Strongly correlated large-scale firing rate fluctuations on slow behaviorally relevant timescales of hundreds of milliseconds are shown by members of the same assembly whereas members of different assemblies show strong negative correlation, and we show how randomly connected spiking networks can generate this activity. Cells display highly irregular spiking with high coefficients of variation, broadly distributed low firing rates, and interspike interval distributions that are consistent with exponentially tailed power laws. Although firing rates vary coherently on slow timescales, precise spiking synchronization is absent in general. Our model only requires the minimal but striatally realistic assumptions of sparse to intermediate random connectivity, weak inhibitory synapses, and sufficient cortical excitation so that some cells are depolarized above the firing threshold during up states. Our results are in good qualitative agreement with experimental studies, consistent with recently determined striatal anatomy and physiology, and support a new view of endogenously generated metastable state switching dynamics of the striatal network underlying its information processing operations.

Characterization of angiotensin-converting enzyme inhibitory activity of fermented milk produced by Lactobacillus helveticus.

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Chen, Yongfu; Li, Changkun; Xue, Jiangang; Kwok, Lai-yu; Yang, Jie; Zhang, Heping; Menghe, Bilige

2015-08-01

Hypertension affects up to 30% of the adult population in most countries. It is a known risk factor for cardiovascular diseases, including coronary heart disease, peripheral artery disease, and stroke. Owing to the increased health awareness of consumers, the application of angiotensin-converting enzyme (ACE)-inhibitory peptides produced by Lactobacillushelveticus to prevent or control high blood pressure has drawn wide attention. A total of 59 L. helveticus strains were isolated from traditional fermented dairy products and the ACE-inhibitory activity of the fermented milks produced with the isolated microorganisms was assayed. The ACE-inhibitory activity of 38 L. helveticus strains was more than 50%, and 3 strains (IMAU80872, IMAU80852, and IMAU80851) expressing the highest ACE-inhibitory activity were selected for further studies. Particularly, the gastrointestinal protease tolerance and thermostability of the ACE-inhibitory activity in the fermented milks were assessed. Based on these 2 criteria, IMAU80872 was found to be superior over the other 2 strains. Furthermore, IMAU80872 exhibited a high in vitro ACE-inhibitory activity at the following fermentation conditions: fermentation temperature at 40°C, inoculation concentration of 1×10(6) cfu/mL, and fermentation for 18h. Finally, by using ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry analysis, we observed changes of the metabolome along the milk fermentation process of IMAU80872. Furthermore, 6 peptides were identified, which might have ACE-inhibitory activity. In conclusion, we identified a novel ACE-inhibitory L. helveticus strain suitable for the production of fermented milk or other functional dairy products. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Antioxidant and α-glucosidase inhibitory ingredients identified from Jerusalem artichoke flowers.

Science.gov (United States)

Wang, Yan-Ming; Zhao, Jian-Qiang; Yang, Jun-Li; Idong, Pema Tsering; Mei, Li-Juan; Tao, Yan-Duo; Shi, Yan-Ping

2017-11-09

Jerusalem artichoke (JA, Helianthus tuberosus L.) has been researched extensively due to its wide range of uses, but there are limited studies on its flowers. In this study, we report the first detailed phytochemical study on JA flowers, which yielded 21 compounds. Compound 4 was identified as a major water-soluble yellow pigment of JA flowers. In addition, the methanol extract of JA flowers and the isolates were evaluated for their antioxidant and α-glucosidase inhibitory activities. Among the tested compounds, compound 13 showed the strongest ABTS + free radical scavenging activity with SC 50 value of 2.30 ± 0.13 μg/mL, and compound 6 showed most potent α-glucosidase inhibitory activity with inhibition rate of 60.0% ± 10.3% at a concentration of 250 μg/mL. Results showed that methanol extract of JA flowers exhibited antioxidant and α-glucosidase inhibitory activities which could be attributed to its phenolic ingredients including chlorogenic acid derivatives, flavonoids and phenols.

Essential Oils from Ugandan Aromatic Medicinal Plants: Chemical Composition and Growth Inhibitory Effects on Oral Pathogens

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Francis Ocheng

2015-01-01

Full Text Available The study assessed the growth inhibitory effects of essential oils extracted from ten Ugandan medicinal plants (Bidens pilosa, Helichrysum odoratissimum, Vernonia amygdalina, Hoslundia opposita, Ocimum gratissimum, Cymbopogon citratus, Cymbopogon nardus, Teclea nobilis, Zanthoxylum chalybeum, and Lantana trifolia used traditionally in the management of oral diseases against oral pathogens. Chemical compositions of the oils were explored by GC-MS. Inhibitory effects of the oils were assessed on periodontopathic Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans and cariogenic Streptococcus mutans and Lactobacillus acidophilus using broth dilution methods at concentrations of 1%, 0.1%, and 0.01%. The most sensitive organism was A. actinomycetemcomitans. Its growth was markedly inhibited by six of the oils at all the concentrations tested. Essential oil from C. nardus exhibited the highest activity with complete growth inhibition of A. actinomycetemcomitans and P. gingivalis at all the three concentrations tested, the major constituents in the oil being mainly oxygenated sesquiterpenes. Most of the oils exhibited limited effects on L. acidophilus. We conclude that essential oils from the studied plants show marked growth inhibitory effects on periodontopathic A. actinomycetemcomitans and P. gingivalis, moderate effects on cariogenic S. mutans, and the least effect on L. acidophilus. The present study constitutes a basis for further investigations and development of certain oils into alternative antiplaque agents.

Essential Oils from Ugandan Aromatic Medicinal Plants: Chemical Composition and Growth Inhibitory Effects on Oral Pathogens

Science.gov (United States)

Ocheng, Francis; Bwanga, Freddie; Joloba, Moses; Softrata, Abier; Azeem, Muhammad; Pütsep, Katrin; Borg-Karlson, Anna-Karin; Obua, Celestino; Gustafsson, Anders

2015-01-01

The study assessed the growth inhibitory effects of essential oils extracted from ten Ugandan medicinal plants (Bidens pilosa, Helichrysum odoratissimum, Vernonia amygdalina, Hoslundia opposita, Ocimum gratissimum, Cymbopogon citratus, Cymbopogon nardus, Teclea nobilis, Zanthoxylum chalybeum, and Lantana trifolia) used traditionally in the management of oral diseases against oral pathogens. Chemical compositions of the oils were explored by GC-MS. Inhibitory effects of the oils were assessed on periodontopathic Porphyromonas gingivalis and Aggregatibacter actinomycetemcomitans and cariogenic Streptococcus mutans and Lactobacillus acidophilus using broth dilution methods at concentrations of 1%, 0.1%, and 0.01%. The most sensitive organism was A. actinomycetemcomitans. Its growth was markedly inhibited by six of the oils at all the concentrations tested. Essential oil from C. nardus exhibited the highest activity with complete growth inhibition of A. actinomycetemcomitans and P. gingivalis at all the three concentrations tested, the major constituents in the oil being mainly oxygenated sesquiterpenes. Most of the oils exhibited limited effects on L. acidophilus. We conclude that essential oils from the studied plants show marked growth inhibitory effects on periodontopathic A. actinomycetemcomitans and P. gingivalis, moderate effects on cariogenic S. mutans, and the least effect on L. acidophilus. The present study constitutes a basis for further investigations and development of certain oils into alternative antiplaque agents. PMID:26170872

Do Children with Better Inhibitory Control Donate More? Differentiating between Early and Middle Childhood and Cool and Hot Inhibitory Control

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Jian Hao

2017-12-01

Full Text Available Inhibitory control may play an important part in prosocial behavior, such as donating behavior. However, it is not clear at what developmental stage inhibitory control becomes associated with donating behavior and which aspects of inhibitory control are related to donating behavior during development in early to middle childhood. The present study aimed to clarify these issues with two experiments. In Experiment 1, 103 3- to 5-year-old preschoolers completed cool (Stroop-like and hot (delay of gratification inhibitory control tasks and a donating task. The results indicated that there were no relationships between cool or hot inhibitory control and donating behavior in the whole group and each age group of the preschoolers. In Experiment 2, 140 elementary school children in Grades 2, 4, and 6 completed cool (Stroop-like and hot (delay of gratification inhibitory control tasks and a donating task. The results showed that inhibitory control was positively associated with donating behavior in the whole group. Cool and hot inhibitory control respectively predicted donating behavior in the second and sixth graders. Therefore, the present study reveals that donating behavior increasingly relies on specific inhibitory control, i.e., hot inhibitory control as children grow in middle childhood.

Jojoba seed meal proteins associated with proteolytic and protease inhibitory activities.

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Shrestha, Madan K; Peri, Irena; Smirnoff, Patricia; Birk, Yehudith; Golan-Goldhirsh, Avi

2002-09-25

The jojoba, Simmondsia chinensis, is a characteristic desert plant native to the Sonoran desert. The jojoba meal after oil extraction is rich in protein. The major jojoba proteins were albumins (79%) and globulins (21%), which have similar amino acid compositions and also showed a labile thrombin-inhibitory activity. SDS-PAGE showed two major proteins at 50 kDa and 25 kDa both in the albumins and in the globulins. The 25 kDa protein has trypsin- and chymotrypsin-inhibitory activities. In vitro digestibility of the globulins and albumins resembled that of casein and soybean protein concentrates and was increased after heat treatment. The increased digestibility achieved by boiling may be attributed to inactivation of the protease inhibitors and denaturation of proteins.

Analysis and Evaluation of the Inhibitory Mechanism of a Novel Angiotensin-I-Converting Enzyme Inhibitory Peptide Derived from Casein Hydrolysate.

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Tu, Maolin; Liu, Hanxiong; Zhang, Ruyi; Chen, Hui; Mao, Fengjiao; Cheng, Shuzhen; Lu, Weihong; Du, Ming

2018-04-25

Casein hydrolysates exert various biological activities, and the responsible functional peptides are being identified from them continuously. In this study, the tryptic casein hydrolysate was fractionated by an ultrafiltration membrane (3 kDa), and the peptides were identified by capillary electrophoresis-quadrupole-time-of-flight-tandem mass spectrometry. Meanwhile, in silico methods were used to analyze the toxicity, solubility, stability, and affinity between the peptides and angiotensin-I-converting enzyme (ACE). Finally, a new angiotensin-I-converting enzyme inhibitory (ACEI) peptide, EKVNELSK, derived from α s1 -casein (fragment 35-42) was screened. The half maximal inhibitory concentration value of the peptide is 5.998 mM, which was determined by a high-performance liquid chromatography method. The Lineweaver-Burk plot indicated that this peptide is a mixed-type inhibitor against ACE. Moreover, Discovery Studio 2017 R2 software was adopted to perform molecular docking to propose the potential mechanisms underlying the ACEI activity of the peptide. These results indicated that EKVNELSK is a new ACEI peptide identified from casein hydrolysate.

Inhibitory Effects of Daiokanzoto (Da-Huang-Gan-Cao-Tang on P-Glycoprotein

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Yuka Watanabe

2012-01-01

Full Text Available We have studied the effects of various Kampo medicines on P-glycoprotein (P-gp, a drug transporter, in vitro. The present study focused on Daiokanzoto (Da-Huang-Gan-Cao-Tang, which shows the most potent inhibitory effects on P-gp among the 50 Kampo medicines studied, and investigated the P-gp inhibitory effects of Daiokanzoto herbal ingredients (rhubarb and licorice root and their components by an ATPase assay using human P-gp membrane. Both rhubarb and licorice root significantly inhibited ATPase activity, and the effects of rhubarb were more potent than those of licorice root. The content of rhubarb in Daiokanzoto is double that in licorice root, and the inhibition patterns of Daiokanzoto and rhubarb involve both competitive and noncompetitive inhibition, suggesting that the inhibitory effects of Daiokanzoto are mainly due to rhubarb. Concerning the components of rhubarb, concentration-dependent inhibitory effects were observed for (−-catechin gallate, (−-epicatechin gallate, and (−-epigallocatechin gallate. In conclusion, rhubarb may cause changes in the drug dispositions of P-gp substrates through the inhibition of P-gp. It appears that attention should be given to the interactions between these drugs and Kampo medicines containing rhubarb as an herbal ingredient.

Eye Gaze and Aging: Selective and Combined Effects of Working Memory and Inhibitory Control

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Trevor J. Crawford

2017-11-01

Full Text Available Eye-tracking is increasingly studied as a cognitive and biological marker for the early signs of neuropsychological and psychiatric disorders. However, in order to make further progress, a more comprehensive understanding of the age-related effects on eye-tracking is essential. The antisaccade task requires participants to make saccadic eye movements away from a prepotent stimulus. Speculation on the cause of the observed age-related differences in the antisaccade task largely centers around two sources of cognitive dysfunction: inhibitory control (IC and working memory (WM. The IC account views cognitive slowing and task errors as a direct result of the decline of inhibitory cognitive mechanisms. An alternative theory considers that a deterioration of WM is the cause of these age-related effects on behavior. The current study assessed IC and WM processes underpinning saccadic eye movements in young and older participants. This was achieved with three experimental conditions that systematically varied the extent to which WM and IC were taxed in the antisaccade task: a memory-guided task was used to explore the effect of increasing the WM load; a Go/No-Go task was used to explore the effect of increasing the inhibitory load; a ‘standard’ antisaccade task retained the standard WM and inhibitory loads. Saccadic eye movements were also examined in a control condition: the standard prosaccade task where the load of WM and IC were minimal or absent. Saccade latencies, error rates and the spatial accuracy of saccades of older participants were compared to the same measures in healthy young controls across the conditions. The results revealed that aging is associated with changes in both IC and WM. Increasing the inhibitory load was associated with increased reaction times in the older group, while the increased WM load and the inhibitory load contributed to an increase in the antisaccade errors. These results reveal that aging is associated with

Eye Gaze and Aging: Selective and Combined Effects of Working Memory and Inhibitory Control.

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Crawford, Trevor J; Smith, Eleanor S; Berry, Donna M

2017-01-01

Eye-tracking is increasingly studied as a cognitive and biological marker for the early signs of neuropsychological and psychiatric disorders. However, in order to make further progress, a more comprehensive understanding of the age-related effects on eye-tracking is essential. The antisaccade task requires participants to make saccadic eye movements away from a prepotent stimulus. Speculation on the cause of the observed age-related differences in the antisaccade task largely centers around two sources of cognitive dysfunction: inhibitory control (IC) and working memory (WM). The IC account views cognitive slowing and task errors as a direct result of the decline of inhibitory cognitive mechanisms. An alternative theory considers that a deterioration of WM is the cause of these age-related effects on behavior. The current study assessed IC and WM processes underpinning saccadic eye movements in young and older participants. This was achieved with three experimental conditions that systematically varied the extent to which WM and IC were taxed in the antisaccade task: a memory-guided task was used to explore the effect of increasing the WM load; a Go/No-Go task was used to explore the effect of increasing the inhibitory load; a 'standard' antisaccade task retained the standard WM and inhibitory loads. Saccadic eye movements were also examined in a control condition: the standard prosaccade task where the load of WM and IC were minimal or absent. Saccade latencies, error rates and the spatial accuracy of saccades of older participants were compared to the same measures in healthy young controls across the conditions. The results revealed that aging is associated with changes in both IC and WM. Increasing the inhibitory load was associated with increased reaction times in the older group, while the increased WM load and the inhibitory load contributed to an increase in the antisaccade errors. These results reveal that aging is associated with changes in both IC and

A cyclohexanecarboxamide derivative with inhibitory effects on Schistosoma mansoni cercarial serine protease and penetration of mice skin by the parasite.

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Bahgat, Mahmoud; Aboul-Enein, Mohamed N; El Azzouny, Aida A; Maghraby, Amany; Ruppel, Andreas; Soliman, Wael M

2009-01-01

A cyclohexanecarboxamide derivative, N-phenyl-N-[1-(piperidine-1-carbonyl)cyclohexyl] benzamide (MNRC-5), was evaluated for its inhibitory effects on Schistosoma mansoni cercarial serine protease activity and cercarial penetration. MNRC-5 exerted an inhibitory effect on S. mansoni cercarial serine protease at serial concentrations of the specific chromogenic substrate Boc-Val-Leu-Gly-Arg-PNA for such enzyme family and the inhibitory coefficient (Ki) value was deduced. Moreover, topical treatment of mice tails with the most potent inhibitory concentration of MNRC-5 formulated in jojoba oil successfully blocked cercarial penetration as demonstrated by a significant reduction (75%; p jojoba oil base containing no MNRC-5. In addition, the IgM and IgG reactivities to crude S. mansoni cercarial, worm and egg antigens were generally lower in sera from treated infected mice than untreated infected mice. In conclusion, we report on a new serine protease inhibitor capable for blocking penetration of host skin by S. mansoni cercariae as measured by lowering worm burden and decrease in the levels of both IgM and IgG towards different bilharzial antigens upon topical treatment.

Evaluation of Traditional Indian Antidiabetic Medicinal Plants for Human Pancreatic Amylase Inhibitory Effect In Vitro

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Sudha Ponnusamy

2011-01-01

Full Text Available Pancreatic α-amylase inhibitors offer an effective strategy to lower the levels of post prandial hyperglycemia via control of starch breakdown. Eleven Ayurvedic Indian medicinal plants with known hypoglycemic properties were subjected to sequential solvent extraction and tested for α-amylase inhibition, in order to assess and evaluate their inhibitory potential on pancreatic α-amylase. Analysis of 91 extracts, showed that 10 exhibited strong Human Pancreatic Amylase (HPA inhibitory potential. Of these, 6 extracts showed concentration dependent inhibition with IC50 values, namely, cold and hot water extracts from Ficus bengalensis bark (4.4 and 125 μgmL-1, Syzygium cumini seeds (42.1 and 4.1 μgmL-1, isopropanol extracts of Cinnamomum verum leaves (1.0 μgmL-1 and Curcuma longa rhizome (0.16 μgmL-1. The other 4 extracts exhibited concentration independent inhibition, namely, methanol extract of Bixa orellana leaves (49 μgmL-1, isopropanol extract from Murraya koenigii leaves (127 μgmL-1, acetone extracts from C. longa rhizome (7.4 μgmL-1 and Tribulus terrestris seeds (511 μgmL-1. Thus, the probable mechanism of action of the above fractions is due to their inhibitory action on HPA, thereby reducing the rate of starch hydrolysis leading to lowered glucose levels. Phytochemical analysis revealed the presence of alkaloids, proteins, tannins, cardiac glycosides, flavonoids, saponins and steroids as probable inhibitory compounds.

Plasticity of cortical excitatory-inhibitory balance.

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Froemke, Robert C

2015-07-08

Synapses are highly plastic and are modified by changes in patterns of neural activity or sensory experience. Plasticity of cortical excitatory synapses is thought to be important for learning and memory, leading to alterations in sensory representations and cognitive maps. However, these changes must be coordinated across other synapses within local circuits to preserve neural coding schemes and the organization of excitatory and inhibitory inputs, i.e., excitatory-inhibitory balance. Recent studies indicate that inhibitory synapses are also plastic and are controlled directly by a large number of neuromodulators, particularly during episodes of learning. Many modulators transiently alter excitatory-inhibitory balance by decreasing inhibition, and thus disinhibition has emerged as a major mechanism by which neuromodulation might enable long-term synaptic modifications naturally. This review examines the relationships between neuromodulation and synaptic plasticity, focusing on the induction of long-term changes that collectively enhance cortical excitatory-inhibitory balance for improving perception and behavior.

Inhibitory activities of microalgal extracts against Epstein-Barr Virus (EBV antigen expression in lymphoblastoid cells

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Koh Yih Yih

2014-01-01

Full Text Available The inhibitory activities of microalgal extracts against the expression of three EBV antigens, latent membrane protein (LMP1, Epstein-Barr nuclear antigen (EBNA1 and Z Epstein-Barr reactivation activator (ZEBRA were assessed by immunocytochemistry. The observation that the methanol extracts and their fractions from Ankistrodesmus convolutus, Synechococcus elongatus and Spirulina platensis exhibited inhibitory activity against EBV proteins in three Burkitt’s lymphoma cell lines at concentrations as low as 20 μg/ml suggests that microalgae could be a potential source of antiviral compounds against EBV.

An apple oligogalactan potentiates the growth inhibitory effect of celecoxib on colorectal cancer.

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Li, Yuhua; Niu, Yinbo; Sun, Yang; Mei, Lin; Zhang, Bangle; Li, Qian; Liu, Li; Zhang, Rong; Chen, Jianfa; Mei, Qibing

2014-01-01

Multiple studies have indicated that selective cyclooxygenase-2 (COX-2) inhibitors possess clinically chemopreventive and preclinically anticancer activities. Their long-term use, however, may be limited by the cardiovascular toxicity. This study tried to investigate whether an apple oligogalactan (AOG) could enhance the growth inhibitory effect of celecoxib on colorectal cancer. Caco-2 and HT-29 cell lines were exposed to different concentrations of AOG (0-1 g/L), celecoxib (0-25 μmol/L), and their combination. COX-2 levels were assessed by reverse transcription PCR and Western blot. COX-2 activity was evaluated by measuring prostaglandin E2 concentration. A colitis-associated colorectal cancer (CACC) mouse model was used to determine the effect of the combination in vivo. AOG (0.1-0.5 g/L) could potentiate the inhibitory effect of physiologic doses of celecoxib (5 μmol/L) on cell growth and decrease COX-2 expressions both at RNA and protein levels. In vivo, the combination (2.5% AOG plus 0.04% celecoxib, w/w) prevented against CACC in mice effectively. Our data indicate that AOG could potentiate the growth inhibitory effect of celecoxib on colorectal cancer both in vitro and in vivo through influencing the expression and function of COX-2 and phosphorylation of MAPKs, which suggests a new possible combinatorial strategy in colorectal cancer therapy.

Fruit Wines Inhibitory Activity Against α-Glucosidase.

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Cakar, Uros; Grozdanic, Nada; Petrovic, Aleksandar; Pejin, Boris; Nastasijevic, Branislav; Markovic, Bojan; Dordevic, Brizita

2017-01-01

Fruit wines are well known for their profound health-promoting properties including both enzyme activations and inhibitions. They may act preventive in regard to diabetes melitus and other chronic diseases. Potential α-glucosidase inhibitory activity of fruit wines made from blueberry, black chokeberry, blackberry, raspberry and sour cherry was the subject of this study. In order to increase the alcohol content due to enriched extraction of total phenolics, sugar was added in the fruit pomace of the half of the examined fruit wine samples. Compared with acarbose used as a positive control (IC50 = 73.78 µg/mL), all fruit wine samples exhibited higher α-glucosidase inhibitory activity. Indeed, blueberry wine samples stood out, both prepared with IC50 = 24.14 µg/mL, lyophilised extract yield 3.23% and without IC50 = 46.39 µg/mL, lyophilised extract yield 2.89% and with addition of sugar before fermentation. Chlorogenic acid predominantly contributed to α-glucosidase inhibitory activity of the blueberry, black chokeberry and sour cherry wine samples. However, ellagic acid, a potent α-glucosidase inhibitor possessing a planar structure, only slightly affected the activity of the blueberry wine samples, due to the lower concentration. In addition to this, molecular docking study of chlorogenic acid pointed out the importance of binding energy (-8.5 kcal/mol) for the inhibition of the enzyme. In summary, fruit wines made from blueberry should be primarily taken into consideration as a medicinal food targeting diabetes mellitus type 2 in the early stage, if additional studies would confirm their therapeutic potential for the control of postprandial hyperglycemia. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Taxonomic minimalism.

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Beattle, A J; Oliver, I

1994-12-01

Biological surveys are in increasing demand while taxonomic resources continue to decline. How much formal taxonomy is required to get the job done? The answer depends on the kind of job but it is possible that taxonomic minimalism, especially (1) the use of higher taxonomic ranks, (2) the use of morphospecies rather than species (as identified by Latin binomials), and (3) the involvement of taxonomic specialists only for training and verification, may offer advantages for biodiversity assessment, environmental monitoring and ecological research. As such, formal taxonomy remains central to the process of biological inventory and survey but resources may be allocated more efficiently. For example, if formal Identification is not required, resources may be concentrated on replication and increasing sample sizes. Taxonomic minimalism may also facilitate the inclusion in these activities of important but neglected groups, especially among the invertebrates, and perhaps even microorganisms. Copyright © 1994. Published by Elsevier Ltd.

Minimum inhibitory concentration of the plant extracts′ combinations against dental caries and plaque microorganisms: An in vitro study

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B R Chandra Shekar

2016-01-01

Full Text Available Introduction: Oral health status has witnessed marked advances in many industrialized countries. However, dental caries is consistently increasing in developing countries, and periodontal diseases are among most common afflictions to humankind. Approach best suited for developing countries is to focus on the prevention with innovative strategies. Hence, evolution of novel, innovative strategies to prevent dental caries and periodontal diseases is need of hour. Objective: To determine minimum inhibitory concentration (MIC of combinations of Acacia nilotica, Murraya koenigii L. Sprengel, Eucalyptus hybrid, and Psidium guajava against dental caries and plaque microorganisms and to qualitatively identify various phytochemical constituents in individual plant extracts and their quadruple combinations. Materials and Methods: MIC of the combinations of A. nilotica, M. koenigii L. Sprengel, Eucalyptus hybrid, and P. guajava on Streptococcus mutans, Lactobacillus acidophilus (dental caries bacteria, Streptococcus sanguis, Streptococcus salivarius (primary plaque colonizers, Fusobacterium nucleatum (secondary plaque colonizer, and Porphyromonas gingivalis (tertiary plaque colonizer was determined using broth dilution method. Series of dilutions of quadruple combinations ranging from 0.05% to 1.5% were prepared. 100 μL of each serial dilution of quadruple combinations was added to each tube containing bacterial culture. The optical density was noted after incubation in each tube to estimate the MIC for each bacterium. Results: MIC of the polyherbal combinations on S. mutans, S. sanguis, S. salivarius, L. acidophilus, F. nucleatum, and P. gingivalis was found to be 0.25%, 0.05%, 0.05%, 0.1%, 0.25%, and 0.25%, respectively. Conclusion: The quadruple combinations of these four plant extracts could be considered in the evolution of an indigenous polyherbal mouth rinse as the formulation inhibited all the bacteria tested in the present study at low

Do piperacillin/tazobactam and other antibiotics with inhibitory activity against Clostridium difficile reduce the risk for acquisition of C. difficile colonization?

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Kundrapu, Sirisha; Sunkesula, Venkata C K; Jury, Lucy A; Cadnum, Jennifer L; Nerandzic, Michelle M; Musuuza, Jackson S; Sethi, Ajay K; Donskey, Curtis J

2016-04-18

Systemic antibiotics vary widely in in vitro activity against Clostridium difficile. Some agents with activity against C. difficile (e.g., piperacillin/tazobactam) inhibit establishment of colonization in mice. We tested the hypothesis that piperacillin/tazobactam and other agents with activity against C. difficile achieve sufficient concentrations in the intestinal tract to inhibit colonization in patients. Point-prevalence culture surveys were conducted to compare the frequency of asymptomatic rectal carriage of toxigenic C. difficile among patients receiving piperacillin/tazobactam or other inhibitory antibiotics (e.g. ampicillin, linezolid, carbapenems) versus antibiotics lacking activity against C. difficile (e.g., cephalosporins, ciprofloxacin). For a subset of patients, in vitro inhibition of C. difficile (defined as a reduction in concentration after inoculation of vegetative C. difficile into fresh stool suspensions) was compared among antibiotic treatment groups. Of 250 patients, 32 (13 %) were asymptomatic carriers of C. difficile. In comparison to patients receiving non-inhibitory antibiotics or prior antibiotics within 90 days, patients currently receiving piperacillin/tazobactam were less likely to be asymptomatic carriers (1/36, 3 versus 7/36, 19 and 15/69, 22 %, respectively; P = 0.024) and more likely to have fecal suspensions with in vitro inhibitory activity against C. difficile (20/28, 71 versus 3/11, 27 and 4/26, 15 %; P = 0.03). Patients receiving other inhibitory antibiotics were not less likely to be asymptomatic carriers than those receiving non-inhibitory antibiotics. Our findings suggest that piperacillin/tazobactam achieves sufficient concentrations in the intestinal tract to inhibit C. difficile colonization during therapy.

Mechanistic Study of the Inhibitory Effect of Kaempferol on Uterine Fibroids In Vitro.

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Li, Yanxia; Ding, Zhaoxia; Wu, Chuanzhong

2016-12-08

BACKGROUND This study examined the effect of kaempferol on uterine fibroids in vitro and the underlying mechanism, and investigated the potential of kaempferol as a clinical drug for the treatment of uterine fibroids. MATERIAL AND METHODS Uterine fibroid tissue and surrounding smooth muscle tissue were collected for primary culture. Different concentrations of kaempferol (12 μM, 24 μM, and 48 μM) were used to treat the cells for 24, 48, and 72 hours. Ethanol was used in the control group. A CCK-8 colorimetric assay was used to detect cell proliferation. Real-time PCR and immunoblot were used to detect estrogen receptor (ER), insulin-like growth factor-1 (IGF-1), and vascular endothelial growth factor (VEGF) levels in mRNA and protein. RESULTS The differences in proliferation at different time points and concentrations of kaempferol were statistically significant. The inhibitory effect of kaempferol on mRNA levels of ER and IGF, and protein levels of ER, VEGF, and IGF-1 were positively correlated with kaempferol concentration. Changes in kaempferol concentration showed no effect on VEGF mRNA expression. Treatment with kaempferol significantly lowered myocardin levels in uterine fibroid tissue compared to normal uterine smooth muscle (PKaempferol might be used for clinical treatment of uterine fibroids due to its inhibitory effect on the proliferation of uterine fibroids cells.

Ribosomal binding region for the antibiotic tiamulin: stoichiometry, subunit location, and affinity for various analogs.

Science.gov (United States)

Högenauer, G; Ruf, C

1981-01-01

Equilibrium dialysis experiments with a highly purified preparation of labeled tiamulin, a semisynthetic derivative of the antibiotic pleuromutilin, and Escherichia coli ribosomes allowed the determination of two binding sites for the drug. The binding reaction showed a cooperative effect. Of the two subunits, the 50S particle was able to bind the antibiotic in a 1:1 stoichiometry. Hence, the 50S subunit contributed predominantly to the binding energy which held the antibiotic to the ribosomes. The 30S subunit, showing no strong affinity for the drug, may be needed for the generation of the second binding site in the 70S particle. If depleted of ammonium ions, 70S ribosomes lost their binding capacity for the antibiotic. The attachment sites for tiamulin could be restored by heating the ribosomes to 40 degrees C in the presence of either ammonium ions or the antibiotic. Other pleuromutilin derivatives displaced labeled tiamulin from its ribosomal binding sites. By quantifying this competition, the relative affinity of various pleuromutilin derivatives for E. coli ribosomes was determined. The binding correlated with the minimal inhibitory concentrations of these compounds against E. coli. When compared with the minimal inhibitory concentrations of these compounds against E. coli. When compared with the minimal inhibitory concentrations against E. coli. When compared with the minimal inhibitory concentrations against Staphylococcus aureus, the correlation was less strict, but the same trend prevailed. These results suggest that the antibacterial activities of various pleuromutilin derivatives on a given test organism are mainly determined by the strength of binding to the ribosomes within the bacterial cell. PMID:6751216

Predicting blood transfusion in patients undergoing minimally invasive oesophagectomy.

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Schneider, Crispin; Boddy, Alex P; Fukuta, Junaid; Groom, William D; Streets, Christopher G

2014-12-01

To evaluate predictors of allogenic blood transfusion requirements in patients undergoing minimal invasive oesophagectomy at a tertiary high volume centre for oesophago-gastric surgery. Retrospective analysis of all patients undergoing minimal access oesophagectomy in our department between January 2010 and December 2011. Patients were divided into two groups depending on whether they required a blood transfusion at any time during their index admission. Factors that have been shown to influence perioperative blood transfusion requirements in major surgery were included in the analysis. Binary logistic regression analysis was performed to determine the impact of patient and perioperative characteristics on transfusion requirements during the index admission. A total of 80 patients underwent minimal access oesophagectomy, of which 61 patients had a laparoscopic assisted oesophagectomy and 19 patients had a minimal invasive oesophagectomy. Perioperative blood transfusion was required in 28 patients at any time during hospital admission. On binary logistic regression analysis, a lower preoperative haemoglobin concentration (p blood transfusion requirements. It has been reported that requirement for blood transfusion can affect long-term outcomes in oesophageal cancer resection. Two factors which could be addressed preoperatively; haemoglobin concentration and type of oesophageal resection, may be valuable in predicting blood transfusions in patients undergoing minimally invasive oesophagectomy. Our analysis revealed that preoperative haemoglobin concentration, occurrence of significant complications and type of minimal access oesophagectomy predicted blood transfusion requirements in the patient population examined. Copyright © 2014 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

Impulsivity: A deficiency of inhibitory control?

NARCIS (Netherlands)

Lansbergen, M.M.

2007-01-01

Impulsivity has been defined as acting without thinking. Impulsivity can be quantified by impulsivity questionnaires, but also by behavioral paradigms which tax inhibitory control. Previous research has repeatedly demonstrated deficient inhibitory control in psychopathological samples characterized

Antifungal Effects of Thyme, Agastache and Satureja Essential Oils on Aspergillus fumigatus, Aspergillus flavus and Fusarium solani

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Karim Mardani

2010-09-01

Full Text Available Growth inhibition of Aspergillus fumigatus,Aspergillus flavus and Fusarum solani exposed to the essential oils including Thyme, Agastache and Satureja were studied. Disc Diffusion Method was used to evaluate the fungal growth inhibitory effects of the essential oils. Minimal inhibitory concentration (MIC and minimal fungicidal concentration (MFC of the oils were determined and compared with each other. The results showed that all three essential oils examined, had antifungal effects against three fungi species. The MIC data revealed that Thyme oil was the most effective essential oil with the MIC of 62.5 μl ml-1.

Aldose reductase inhibitory compounds from Xanthium strumarium.

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Yoon, Ha Na; Lee, Min Young; Kim, Jin-Kyu; Suh, Hong-Won; Lim, Soon Sung

2013-09-01

As part of our ongoing search for natural sources of therapeutic and preventive agents for diabetic complications, we evaluated the inhibitory effects of components of the fruit of Xanthium strumarium (X. strumarium) on aldose reductase (AR) and galactitol formation in rat lenses with high levels of glucose. To identify the bioactive components of X. strumarium, 7 caffeoylquinic acids and 3 phenolic compounds were isolated and their chemical structures were elucidated on the basis of spectroscopic evidence and comparison with published data. The abilities of 10 X. strumarium-derived components to counteract diabetic complications were investigated by means of inhibitory assays with rat lens AR (rAR) and recombinant human AR (rhAR). From the 10 isolated compounds, methyl-3,5-di-O-caffeoylquinate showed the most potent inhibition, with IC₅₀ values of 0.30 and 0.67 μM for rAR and rhAR, respectively. In the kinetic analyses using Lineweaver-Burk plots of 1/velocity and 1/substrate, methyl-3,5-di-O-caffeoylquinate showed competitive inhibition of rhAR. Furthermore, methyl-3,5-di-O-caffeoylquinate inhibited galactitol formation in the rat lens and in erythrocytes incubated with a high concentration of glucose, indicating that this compound may be effective in preventing diabetic complications.

Length and coverage of inhibitory decision rules

KAUST Repository

Alsolami, Fawaz

2012-01-01

Authors present algorithms for optimization of inhibitory rules relative to the length and coverage. Inhibitory rules have a relation "attribute ≠ value" on the right-hand side. The considered algorithms are based on extensions of dynamic programming. Paper contains also comparison of length and coverage of inhibitory rules constructed by a greedy algorithm and by the dynamic programming algorithm. © 2012 Springer-Verlag.

Vaginal oxytetracycline concentrations.

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Thin, R N; Al Rawi, Z H; Simmons, P D; Treharne, J; Tabaqchali, S

1979-01-01

Although tetracycline preparations are widely used in departments of genitourinary medicine, or sexually transmitted diseases clinics, little is known of the concentrations of these preparations in genital secretions. For this reason a microbiological method was used for estimating oxytetracycline concentrations in vaginal secretions. These concentrations varied from 0.6 to 6.5 microgram/ml in 19 women who had had sexual contact with a man with non-specific urethritis and who were taking oxytetracycline dihydrate 250 mg four times daily. They were well in excess of the minimum inhibitory concentration of oxytetracycline (0.2 microgram/ml) for the strains of Chlamydia trachomatis isolated from the patients with positive culture results. Thus, oxytetracycline 250 mg four times daily appears to be a satisfactory regimen for the treatment of chlamydial genital infection in women. PMID:509190

Superior Inhibitory Control and Resistance to Mental Fatigue in Professional Road Cyclists.

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Kristy Martin

Full Text Available Given the important role of the brain in regulating endurance performance, this comparative study sought to determine whether professional road cyclists have superior inhibitory control and resistance to mental fatigue compared to recreational road cyclists.After preliminary testing and familiarization, eleven professional and nine recreational road cyclists visited the lab on two occasions to complete a modified incongruent colour-word Stroop task (a cognitive task requiring inhibitory control for 30 min (mental exertion condition, or an easy cognitive task for 10 min (control condition in a randomized, counterbalanced cross-over order. After each cognitive task, participants completed a 20-min time trial on a cycle ergometer. During the time trial, heart rate, blood lactate concentration, and rating of perceived exertion (RPE were recorded.The professional cyclists completed more correct responses during the Stroop task than the recreational cyclists (705±68 vs 576±74, p = 0.001. During the time trial, the recreational cyclists produced a lower mean power output in the mental exertion condition compared to the control condition (216±33 vs 226±25 W, p = 0.014. There was no difference between conditions for the professional cyclists (323±42 vs 326±35 W, p = 0.502. Heart rate, blood lactate concentration, and RPE were not significantly different between the mental exertion and control conditions in both groups.The professional cyclists exhibited superior performance during the Stroop task which is indicative of stronger inhibitory control than the recreational cyclists. The professional cyclists also displayed a greater resistance to the negative effects of mental fatigue as demonstrated by no significant differences in perception of effort and time trial performance between the mental exertion and control conditions. These findings suggest that inhibitory control and resistance to mental fatigue may contribute to successful road cycling

Superior Inhibitory Control and Resistance to Mental Fatigue in Professional Road Cyclists.

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Martin, Kristy; Staiano, Walter; Menaspà, Paolo; Hennessey, Tom; Marcora, Samuele; Keegan, Richard; Thompson, Kevin G; Martin, David; Halson, Shona; Rattray, Ben

2016-01-01

Given the important role of the brain in regulating endurance performance, this comparative study sought to determine whether professional road cyclists have superior inhibitory control and resistance to mental fatigue compared to recreational road cyclists. After preliminary testing and familiarization, eleven professional and nine recreational road cyclists visited the lab on two occasions to complete a modified incongruent colour-word Stroop task (a cognitive task requiring inhibitory control) for 30 min (mental exertion condition), or an easy cognitive task for 10 min (control condition) in a randomized, counterbalanced cross-over order. After each cognitive task, participants completed a 20-min time trial on a cycle ergometer. During the time trial, heart rate, blood lactate concentration, and rating of perceived exertion (RPE) were recorded. The professional cyclists completed more correct responses during the Stroop task than the recreational cyclists (705±68 vs 576±74, p = 0.001). During the time trial, the recreational cyclists produced a lower mean power output in the mental exertion condition compared to the control condition (216±33 vs 226±25 W, p = 0.014). There was no difference between conditions for the professional cyclists (323±42 vs 326±35 W, p = 0.502). Heart rate, blood lactate concentration, and RPE were not significantly different between the mental exertion and control conditions in both groups. The professional cyclists exhibited superior performance during the Stroop task which is indicative of stronger inhibitory control than the recreational cyclists. The professional cyclists also displayed a greater resistance to the negative effects of mental fatigue as demonstrated by no significant differences in perception of effort and time trial performance between the mental exertion and control conditions. These findings suggest that inhibitory control and resistance to mental fatigue may contribute to successful road cycling performance

Fermentation characteristics and angiotensin I-converting enzyme-inhibitory activity of Lactobacillus helveticus isolate H9 in cow milk, soy milk, and mare milk.

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Wang, Jicheng; Li, Changkun; Xue, Jiangang; Yang, Jie; Zhang, Qing; Zhang, Heping; Chen, Yongfu

2015-06-01

Lactobacillus helveticus isolate H9 demonstrated high angiotensin I-converting enzyme (ACE)-inhibitory activity in previous research. Here, we evaluated the fermentation characteristics (pH, titratable acidity, free amino nitrogen, and viable bacterial counts), ACE-inhibitory activity, and contents of Val-Pro-Pro (VPP) and Ile-Pro-Pro (IPP) peptides of stored yogurt (4°C for 28 d) fermented by L. helveticus isolate H9 (initially inoculated at 4 concentrations), from cow, mare, and soy milks. During storage, the pH and titratable acidity remained stable in yogurts produced from all milk types and all inoculation concentrations. The viable bacterial counts in all stored yogurts ranged between 10(6.72) and 10(8.59) cfu/g. The highest ACE-inhibitory activity (70.9-74.5%) was achieved at inoculation concentrations of 5×10(6) cfu/mL. The ACE-inhibitory tripeptides VPP and IPP as determined by ultra-performance liquid chromatography-tandem mass spectrometry were not produced in yogurt made from soy milk or mare milk. These evaluations indicate that L. helveticus H9 has good probiotic properties and would be a promising candidate for production of fermented food with probiotic properties. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Improved water chemistry controls for minimizing degradation of materials

International Nuclear Information System (INIS)

Sawochka, S.G.

1986-01-01

The Electric Power Research Institute and the Steam Generator Owners Group have sponsored several efforts to develop secondary water chemistry guidelines to minimize pressurized water reactor (PWR) steam generator tubing degradation. To develop these guidelines, chemical species known to accelerate corrosion of Alloy 600 were identified, and values for normal and abnormal chemistry situations were established. For example, sodium hydroxide was known to accelerate Alloy 600 intergranular attack stress corrosion cracking; thus, guidelines were developed for blowdown sodium concentrations in recirculating steam generator systems. Similarly, formation of acidic solutions, particularly as a result of chloride ingress at seawater sites, was known to accelerate denting; thus, chloride guidelines were established. A blowdown cation conductivity limit was established to minimize concentrations of other anionic species. Guidelines also were developed for condensate and feedwater chemistry to minimize general corrosion of system materials, thereby minimizing sludge and deposit buildup in the steam generators

Gastric inhibitory polypeptide (GIP) dose-dependently stimulates glucagon secretion in healthy human subjects at euglycaemia

DEFF Research Database (Denmark)

Meier, J J; Gallwitz, B; Siepmann, N

2003-01-01

AIMS/HYPOTHESIS: In the isolated perfused pancreas, gastric inhibitory polypeptide (GIP) has been shown to enhance glucagon secretion at basal glucose concentrations, but in healthy humans no glucagonotropic effect of GIP has yet been reported. Therefore, we studied the effect of GIP on glucagon ...

A randomized prospective study of desflurane versus isoflurane in minimal flow anesthesia using “equilibration time” as the change-over point to minimal flow

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Mallik, Tanuja; Aneja, S; Tope, R; Muralidhar, V

2012-01-01

Background: In the administration of minimal flow anesthesia, traditionally a fixed time period of high flow has been used before changing over to minimal flow. However, newer studies have used “equilibration time” of a volatile anesthetic agent as the change-over point. Materials and Methods: A randomized prospective study was conducted on 60 patients, who were divided into two groups of 30 patients each. Two volatile inhalational anesthetic agents were compared. Group I received desflurane (n = 30) and group II isoflurane (n = 30). Both the groups received an initial high flow till equilibration between inspired (Fi) and expired (Fe) agent concentration were achieved, which was defined as Fe/Fi = 0.8. The mean (SD) equilibration time was obtained for both the agent. Then, a drift in end-tidal agent concentration during the minimal flow anesthesia and recovery profile was noted. Results: The mean equilibration time obtained for desflurane and isoflurane were 4.96 ± 1.60 and 16.96 ± 9.64 min (P < 0.001). The drift in end-tidal agent concentration over time was minimal in the desflurane group (P = 0.065). Recovery time was 5.70 ± 2.78 min in the desflurane group and 8.06 ± 31 min in the isoflurane group (P = 0.004). Conclusion: Use of equilibration time of the volatile anesthetic agent as a change-over point, from high flow to minimal flow, can help us use minimal flow anesthesia, in a more efficient way. PMID:23225926

New tyrosinase inhibitory decapeptide: Molecular insights into the role of tyrosine residues.

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Ochiai, Akihito; Tanaka, Seiya; Imai, Yuta; Yoshida, Hisashi; Kanaoka, Takumi; Tanaka, Takaaki; Taniguchi, Masayuki

2016-06-01

Tyrosinase, a rate-limiting enzyme in melanin biosynthesis, catalyzes the hydroxylation of l-tyrosine to 3,4-dihydroxy-l-phenylalanine (l-dopa) (monophenolase reaction) and the subsequent oxidation of l-dopa to l-dopaquinone (diphenolase reaction). Thus, tyrosinase inhibitors have been proposed as skin-lightening agents; however, many of the existing inhibitors cannot be widely used in the cosmetic industry due to their high cytotoxicity and instability. On the other hand, some tyrosinase inhibitory peptides have been reported as safe. In this study, we found that the peptide TH10, which has a similar sequence to the characterized inhibitory peptide P4, strongly inhibits the monophenolase reaction with a half-maximal inhibitory concentration of 102 μM. Seven of the ten amino acid residues in TH10 were identical to P4; however, TH10 possesses one N-terminal tyrosine, whereas P4 contains three tyrosine residues located at its N-terminus, center, and C-terminus. Subsequent analysis using sequence-shuffled variants indicated that the tyrosine residues located at the N-terminus and center of P4 have little to no contribution to its inhibitory activity. Furthermore, docking simulation analysis of these peptides with mushroom tyrosinase demonstrated that the active tyrosine residue was positioned close to copper ions, suggesting that TH10 and P4 bind to tyrosinase as a substrate analogue. Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

The frontal lobes and inhibitory function

International Nuclear Information System (INIS)

Konishi, Seiki

2011-01-01

Neuropsychological studies using traditional tasks of inhibitory functions, such as the Wisconsin card sorting test (WCST) and the Go/No-Go Task have revealed that the frontal lobe is responsible for several types of inhibitory functions. However, the detailed psychological nature of the inhibitory functions and the precise location of their critical foci within the frontal lobe remain to be investigated. Functional magnetic resonance imaging provides spatial and temporal resolution that allowed us to illuminate at least 4 frontal regions involved in inhibitory functions: the dorsolateral, ventrolateral, and rostral parts of the frontal lobe and the presupplementary motor area (preSMA). The ventrolateral part of the frontal lobe in the right hemisphere was activated during response inhibition. The preSMA in the left hemisphere was activated during inhibition of proactive interference immediately after the dimension changes of the WCST. The rostral part of the frontal lobe in the left hemisphere was activated during inhibition long after the dimension changes. The dorsolateral part of the frontal lobe in the left hemisphere was activated at the dimension changes in the first time, but not in the second time. These findings provide clues to our understanding of functional differentiation of inhibitory functions and their localization in the frontal lobe. (author)

Antioxidant, ACE-Inhibitory and antibacterial activities of Kluyveromyces marxianus protein hydrolysates and their peptide fractions

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Mahta Mirzaeia

2016-07-01

Full Text Available Background: There has been evidence that proteins are potentially excellent source of antioxidants, antihypertensive and antimicrobial peptides, and that enzymatic hydrolysis is an effective method to release these peptides from protein molecules. The functional properties of protein hydrolysates depends on the protein substrate, the specificity of the enzymes, the conditions used during proteolysis, degree of hydrolysis, and the nature of peptides released including molecular weight, amino acid composition, and hydrophobicity. Context and purpose of this study: The biomass of Kluyveromyces marxianus was considered as a source of ACE inhibitory, antioxidant and antimicrobial peptides. Results: Autolysis and enzymatic hydrolysis were completed respectively, after 96 h and 5 h. Overall, trypsin (18.52% DH and chymotrypsin (21.59% DH treatments were successful in releasing antioxidant and ACE inhibitory peptides. Autolysate sample (39.51% DH demonstrated poor antioxidant and ACE inhibitory activity compared to trypsin and chymotrypsin hydrolysates. The chymotrypsin 3-5 kDa (301.6±22.81 μM TE/mg protein and trypsin < 3 kDa (280.16±39.16 μM TE/mg protein permeate peptide fractions showed the highest DPPH radical scavenging activity. The trypsin <3 kDa permeate peptide fraction showed the highest ABTS radical scavenging (1691.1±48.68 μM TE/mg protein and ACE inhibitory (IC50=0.03±0.001 mg/mL activities. The fraction (MW=5-10 kD obtained after autolysis treatment showed antibacterial activity against St. aureus and Lis. monocytogenes in well diffusion screening. The minimum inhibitory concentration (MIC value was 13.3 mg/mLagainst St. aureus and Lis. monocytogenes calculated by turbidimetric assay and it showed bactericidal activity against St. aureus at 21.3 mg/mL protein concentration. Conclusions: Altogether, the results of this study reveal that K. marxianus proteins contain specific peptides in their sequences which can be released by

Influence of thermodynamic parameter in Lanosterol 14alpha-demethylase inhibitory activity as antifungal agents: a QSAR approach.

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Vasanthanathan, Poongavanam; Lakshmi, Manickavasagam; Arockia Babu, Marianesan; Kaskhedikar, Sathish Gopalrao

2006-06-01

A quantitative structure activity relationship, Hansch approach was applied on twenty compounds of chromene derivatives as Lanosterol 14alpha-demethylase inhibitory activity against eight fungal organisms. Various physicochemical descriptors and reported minimum inhibitory concentration values of different fungal organisms were used as independent variables and dependent variable respectively. The best models for eight different fungal organisms were first validated by leave-one-out cross validation procedure. It was revealed that thermodynamic parameters were found to have overall significant correlationship with anti fungal activity and these studies provide an insight to design new molecules.

[Inhibitory effect of diclofenac sodium on the proliferation of rabbit corneal epithelial cells in vitro].

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Wu, Ningling; Du, Zhiyu

2010-11-01

To investigate the inhibitory effect of diclofenac sodium on rabbit corneal epithelial cells (RCECs) in vitro and explore its pharmacological mechanism. The fresh rabbit cornea was cultured to obtain the primary RCECs, and RCECs of passage 2 were used in this research. The cells were divided into experimental groups, the cells in which were incubated with different concentrations (18.18, 27.27, 36.36, 45.45, 54.55 μg/ml) of diclofenac sodium, and control group. The effect of diclofenac sodium on the proliferation of cells was measured by methyl thiazolyl thiazolium (MTT) assay 24, 48 and 72 h after incubation. While the RCECs were divided into experimental groups, the cells in which were incubated with 9 and 12.5 μg/ml diclofenac sodium, and control group. The cell cycle and apoptotic rate were observed by flow cytometer. MTT assay showed that diclofenac sodium had obvious inhibitory effect on RCECs, and the inhibition rate was increasing along with the increasing concentration of diclofenac sodium and the incubation time(Pdiclofenac sodium, the cells in G0/G1 phase were obviously increased, and the apoptosis cusp and apoptotic rate were increased. Diclofenac sodium exerts significant inhibitory effect on RCECs in a dosage-dependent manner, and it may function by inducing cell apoptosis and ceasing cell cycles.

Antimicrobial effect of blueberry (Vaccinium corymbosum L.) extracts against the growth of Listeria monocytogenes and Salmonella Enteritidis

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We studied the antimicrobial effects of berry extracts obtained from four cultivars (Elliott, Darrow, Bluecrop and Duke) of blueberry (Vaccinium corymbosum L.) on the growth of Listeria monocytogenes and Salmonella Enteritidis. The minimal inhibitory concentration (MIC) and minimal bactericidal conc...

[Determination of minimal concentrations of biocorrosion inhibitors by a bioluminescence method in relation to bacteria, participating in biocorrosion].

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Efremenko, E N; Azizov, R E; Makhlis, T A; Abbasov, V M; Varfolomeev, S D

2005-01-01

By using a bioluminescence ATP assay, we have determined the minimal concentrations of some biocorrosion inhibitors (Katon, Khazar, VFIKS-82, Nitro-1, Kaspii-2, and Kaspii-4) suppressing most common microbial corrosion agents: Desulfovibrio desulfuricans, Desulfovibrio vulgaris, Pseudomonas putida, Pseudomonas fluorescens, and Acidithiobacillus ferrooxidans. The cell titers determined by the bioluminescence method, including not only dividing cells but also their dormant living counterparts, are two- to sixfold greater than the values determined microbiologically. It is shown that the bioluminescence method can be applied to determination of cell titers in samples of oil-field waters in the presence of iron ions (up to 260 mM) and iron sulfide (to 186 mg/l) and in the absence or presence of biocidal corrosion inhibitors.

A novel interpretation of the Fractional Inhibitory Concentration Index: The case Origanum vulgare L. and Leptospermum scoparium J. R. et G. Forst essential oils against Staphylococcus aureus strains.

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Fratini, Filippo; Mancini, Simone; Turchi, Barbara; Friscia, Elisabetta; Pistelli, Luisa; Giusti, Giulia; Cerri, Domenico

2017-01-01

Origanum vulgare (oregano) and Leptospermum scoparium (manuka) were traditionally employed as natural remedies for infected wounds and skin injuries where Staphylococcus aureus is mainly involved. The first aim of this study was to investigate oregano and manuka essential oils (EOs) chemical compositions and evaluate their antibacterial activity (MIC, Minimum Inhibitory Concentration) against fourteen S. aureus wild strains. The second aim was to evaluate the antibacterial activities of oregano and manuka EOs mixed in different combination (FIC, Fractional Inhibitory Concentration) with an improved chequerboard technique. This allowed to avoid the usual uncertainty in the determination of MIC and FIC values and to obtain a more precise interpretation of FIC indexes (FICIs). Moreover, FICIs were discussed on the basis of a novel interpretation method to evaluate the synergistic/antagonistic effect of EOs mixtures. The most representative compounds in oregano EO were Carvacrol (65.93%), p-Cymene (9.33%) and γ-Terpinene (5.25%), while in manuka EO were Leptospermone (31.65%), cis-Calamenene (15.93%) and Flavesone (6.92%). EOs presented MIC values ranging from 1:2048 to 1:4096 v/v and FIC values ranging from 0.125 to 1. According to our interpretation, a synergistic effect (34.68%), a commutative effect (15.32%) and an indifferent effect (50.00%) and no antagonistic effect were observed. Conversely, according to two previously proposed FICI interpretation models, 1.80% synergistic effect could be observed and, respectively, 98.20% indifferent effect or 48.20% additive effect and 50.00% indifferent effect. As practical results, oregano and manuka EOs may be an effective alternative to chemotherapic drugs in staphylococcal infections and useful tools to enhance food security. Copyright © 2016 Elsevier GmbH. All rights reserved.

Application of Chitosan in vitro to Minimize the Adverse Effects of Salinity in Petunia × atkinsiana D. don

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Marcelina Krupa-Małkiewicz

2018-01-01

Full Text Available The genus Petunia is a plant of high economic importance in the world-wide horticulture. These ornamental plants are often exposed to soil salinity that negatively affectstheir development. Chitosan is a biopolymer with multiple applications in plant breeding but it also minimizes the adverse effectsof abiotic stresses on plant growth. The objective of this study was to investigate the effectsof chitosan on petunia shoots development under salt stress in vitro. In the first experiment, four types of chitosan with molecular weight of 3.33, 8, 10 and 970 kDa in the concentrations of 0, 10, 15 and 20 ppm were supplemented into MS medium. In the second experiment, petunia shoots were grown on MS medium with the addition of different molecular weight of chitosan in the concentration of 15 ppm each and 100 mM NaCl. The results indicated that all of chitosan types and concentrations stimulate the plant growth in comparison to control. However, 15 ppm chitosan concentration was more effective than other concentrations used. Salinity caused a significant reduction in shoot and root length, fresh and dry mass, plant water contents, while chitosan (970 kDa adjusted the salt toxicity. It is concluded that chitosan would be able to stimulate the growth of petunia shoots in vitro independent of their molecular weight. It was observed that the addition of chitosan of 970 kDa to MS medium under salinity conditions may alleviate the inhibitory effect of salt stress on the plant growth.

Tyrosinase inhibitory effects and antioxidative activities of saponins from Xanthoceras Sorbifolia nutshell.

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Hongmei Zhang

Full Text Available Certain saponins are bioactive compounds with anticancer, antivirus and antioxidant activities. This paper discussed inhibitory effects of saponins from Xanthoceras Sorbifolia on tyrosinase, through the research of the rate of tyrosinase catalyzed L-DOPA oxidation. The inhibition rate of tyrosinase activity presented non-linear changes with the saponins concentration. The rate reached 52.0% when the saponins concentration was 0.96 mg/ml. Antioxidant activities of saponins from Xanthoceras Sorbifolia were evaluated by using hydroxyl and superoxide radical scavenging assays. The hydroxyl radical scavenging effects of the saponins were 15.5-68.7%, respectively at the concentration of 0.18-2.52 mg/ml. The superoxide radical scavenging activity reduced from 96.6% to 7.05% with the time increasing at the concentration of 1.44 mg/ml. All the above antioxidant evaluation indicated that saponins from Xanthoceras Sorbifolia exhibited good antioxidant activity in a concentration- dependent manner.

Application of edible coating with starch and carvacrol in minimally processed pumpkin.

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Santos, Adriele R; da Silva, Alex F; Amaral, Viviane C S; Ribeiro, Alessandra B; de Abreu Filho, Benicio A; Mikcha, Jane M G

2016-04-01

The present study evaluated the effect of an edible coating of cassava starch and carvacrol in minimally processed pumpkin (MPP). The minimal inhibitory concentration (MIC) of carvacrol against Escherichia coli, Salmonella enterica serotype Typhimurium, Aeromonas hydrophila, and Staphylococcus aureus was determined. The edible coating that contained carvacrol at the MIC and 2 × MIC was applied to MPP, and effects were evaluated with regard to the survival of experimentally inoculated bacteria and autochthonous microflora in MPP. Total titratable acidity, pH, weight loss, and soluble solids over 7 days of storage under refrigeration was also analyzed. MIC of carvacrol was 312 μg/ml. Carvacrol at the MIC reduced the counts of E. coli and S. Typhimurium by approximately 5 log CFU/g. A. hydrophila was reduced by approximately 8 log CFU/g, and S. aureus was reduced by approximately 2 log CFU/g on the seventh day of storage. Carvacrol at the 2 × MIC completely inhibited all isolates on the first day of Storage. coliforms at 35 °C and 45 °C were not detected (< 3 MPN/g) with either treatment on all days of shelf life. The treatment groups exhibited a reduction of approximately 2 log CFU/g in psychrotrophic counts compared with controls on the last day of storage. Yeast and mold were not detected with either treatment over the same period. The addition of carvacrol did not affect total titratable acidity, pH, or soluble solids and improved weight loss. The edible coating of cassava starch with carvacrol may be an interesting approach to improve the safety and microbiological quality of MPP.

Inhibitory Effect of Curcumin on Candida-albicans compared with Nystatin: an in-vitro Study

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Neda Babaii

2016-10-01

Full Text Available Introduction: Curcumin is the active ingredient in the traditional herbal remedy and dietary spice turmeric (Curcuma longa. Curcumin has a surprisingly wide range of beneficial properties, including anti-inflammatory, antioxidant, chemopreventive and chemotherapeutic activity. on basis of recent studies; it has antifungal and antibacterial effects. The aim of this study was in-vitro evaluation of antifungal effect of curcumin on candida albicans and comparing it with nystatin. Methods: after preparing curcumin powder, 3 laboratory methods were used to evaluate antifungal effect. The first method was cell count technique, used to evaluate the amount of candida albicans after time, in different concentrations of curcumin in Dimethyl sulfoxide (DMSO. The second was cup bioassay, in which inhibitory a zone of curcumin in DMSO was evaluated in sabouraud culture plates; and in third method, inhibitory zones of dried disks; which contained curcumin in DMSO were evaluated. Results: the result of all three methods showed that curcumin has antifungal effect and this effect increases in more concentrations. Conclusion: curcumin has apparent and dose dependent antifungal effect on candida albicans.

Tumor necrosis factor-alpha but not interleukin-1 beta or interleukin-8 concentrations correlate with angiogenic activity of peritoneal fluid from patients with minimal to mild endometriosis

NARCIS (Netherlands)

Maas, J. W.; Calhaz-Jorge, C.; ter Riet, G.; Dunselman, G. A.; de Goeij, A. F.; Struijker-Boudier, H. A.

2001-01-01

OBJECTIVE: To assess the angiogenic activity of peritoneal fluid in women with minimal to mild endometriosis and to investigate the relationship between this activity and the concentration of macrophage-derived angiogenic factors and clinical variables, such as phase of menstrual cycle, type of

PURIFICATION OF ANGIOTENSIN CONVERTING ENZYME INHIBITORY PEPTIDE DERIVED FROM KACANG GOAT MEAT PROTEIN HYDROLYSATE

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J. Jamhari

2014-10-01

Full Text Available The objective of this study was to identify the Angiotensin Converting Enzyme (ACE inhibitorypeptide derived from Kacang goat meat protein hydrolysate. Kacang goat meat loin section washydrolyzed with pepsin, trypsin and chymotrypsin. Protein hydrolysate of Kacang goat meat was thentested the protein concentration and ACE inhibitory activity. ACE inhibitory peptide of the proteinhydrolysate was purified through several steps of purification by column SEP-PAK Plus C18 Cartridgeand RP-HPLC using a Cosmosil column 5PE-SM, 4.6 x 250　mm. The sequence of amino acid of ACEinhibitory peptide was identified by amino acid sequencer. The results showed that amino acidssequence of ACE inhibitory peptide derived from protein hydrolysate of Kacang goat meat was leu-thrglu-ala-pro-leu-asn-pro-lys-ala-arg- asn-glu-lys. It had a molecular weight (MW of 1581 and occurredat the position of 20th to 33rd residues of b-actin of goat meat protein (Capra hircus. The ACE inhibitoryactivity (IC50 of the peptide was 190 mg/mL or 120 mM.

Inhibitory effect of organotin compounds on rat neuronal nitric oxide synthase through interaction with calmodulin

International Nuclear Information System (INIS)

Ohashi, Koji; Kominami, Shiro; Yamazaki, Takeshi; Ohta, Shigeru; Kitamura, Shigeyuki

2004-01-01

Organotin compounds, triphenyltin (TPT), tributyltin, dibutyltin, and monobutyltin (MBT), showed potent inhibitory effects on both L-arginine oxidation to nitric oxide and L-citrulline, and cytochrome c reduction catalyzed by recombinant rat neuronal nitric oxide synthase (nNOS). The two inhibitory effects were almost parallel. MBT and TPT showed the highest inhibitory effects, followed by tributyltin and dibutyltin; TPT and MBT showed inhibition constant (IC 50 ) values of around 10 μM. Cytochrome c reduction activity was markedly decreased by removal of calmodulin (CaM) from the complete mixture, and the decrease was similar to the extent of inhibition by TPT and MBT. The inhibitory effect of MBT on the cytochrome c reducing activity was rapidly attenuated upon dilution of the inhibitor, and addition of a high concentration of CaM reactivated the cytochrome c reduction activity inhibited by MBT. However, other cofactors such as FAD, FMN or tetrahydrobiopterin had no such ability. The inhibitory effect of organotin compounds (100 μM) on L-arginine oxidation of nNOS almost vanished when the amount of CaM was sufficiently increased (150-300 μM). It was confirmed by CaM-agarose column chromatography that the dissociation of nNOS-CaM complex was induced by organotin compounds. These results indicate that organotin compounds disturb the interaction between CaM and nNOS, thereby inhibiting electron transfer from the reductase domain to cytochrome c and the oxygenase domain

Effect of higher minimum inhibitory concentrations of quaternary ammonium compounds in clinical E. coli isolates on antibiotic susceptibilities and clinical outcomes.

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Buffet-Bataillon, S; Branger, B; Cormier, M; Bonnaure-Mallet, M; Jolivet-Gougeon, A

2011-10-01

Quaternary ammonium compounds (QACs) are cationic surfactants used as preservatives and environmental disinfectants. Limited data are available regarding the effect of QACs in the clinical setting. We performed a prospective cohort study in 153 patients with Escherichia coli bacteraemia from February to September 2008 at University Hospital in Rennes. The minimum inhibitory concentrations (MICs) of antibiotics and QACs alkyldimethylbenzylammonium chloride (ADBAC) and didecyldimethylammonium chloride (DDAC) were determined by the agar dilution method. The capacity of biofilm production was assayed using the Crystal Violet method, and mutation frequencies by measuring the capacity of strains to generate resistance to rifampicin. Logistic regression analysis showed that one of the significant factors related to low MICs for ADBAC (≤16 mg/L) and DDAC (≤8 mg/L), was cotrimoxazole susceptibility (odds ratio: 3.72; 95% confidence interval: 1.22-11.24; P=0.02 and OR: 3.61; 95% CI: 1.56-7.56; PAntibiotic susceptibility to cotrimoxazole was strongly associated with susceptibility to amoxicillin and nalidixic acid (PE. coli isolates and antibiotic resistance. Copyright © 2011 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

Evaluation of the tannic acid inhibitory effect against the NorA efflux pump of Staphylococcus aureus.

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Tintino, Saulo R; Oliveira-Tintino, Cícera D M; Campina, Fábia F; Silva, Raimundo L P; Costa, Maria do S; Menezes, Irwin R A; Calixto-Júnior, João T; Siqueira-Junior, José P; Coutinho, Henrique D M; Leal-Balbino, Tereza C; Balbino, Valdir Q

2016-08-01

During the early periods of antibiotic usage, bacterial infections were considered tamed. However, widespread antibiotic use has promoted the emergence of antibiotic-resistant pathogens, including multidrug resistant strains. Active efflux is a mechanism for bacterial resistance to inhibitory substances, known simply as drug efflux pumps. The bacterium Staphylococcus aureus is an important pathogenic bacterium responsible for an array of infections. The NorA efflux pump has been shown to be responsible for moderate fluoroquinolone resistance of S. aureus. The inhibition of the efflux pump was assayed using a sub-inhibitory concentration of standard efflux pump inhibitors and tannic acid (MIC/8), where its capacity to decrease the MIC of Ethidium bromide (EtBr) and antibiotics due to the possible inhibitory effect of these substances was observed. The MICs of EtBr and antibiotics were significantly reduced in the presence of tannic acid, indicating the inhibitory effect of this agent against the efflux pumps of both strains causing a three-fold reduction of the MIC when compared with the control. These results indicate the possible usage of tannic acid as an adjuvant in antibiotic therapy against multidrug resistant bacteria (MDR). Copyright © 2016 Elsevier Ltd. All rights reserved.

Self-restraint spillover: Inhibitory control disrupts appetite regulation among ruminators.

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Schlinkert, Caroline; Koole, Sander L

2017-10-23

People can use inhibitory control to temporarily inhibit their personal preferences to achieve their long-term goals. According to the ego fixation model (Koole et al., 2014), ruminators have difficulties relaxing inhibitory control, leading them to continue inhibiting their personal needs, even when this is no longer required by the situation. Inhibitory control may thus disrupt healthy appetite regulation among ruminators. Among 324 Dutch undergraduate students (218 women; M age  = 21.5), different inhibitory control states were manipulated by varying whether or not participants exerted inhibitory control (Study 1) or priming high versus low inhibitory control (Study 2). All participants then performed a food-tasting task. Healthy appetite regulation was defined as a positive correlation between level of food deprivation and preference for high-calorie foods. For taste ratings, the interaction between inhibitory control and rumination was significant in each study: Inhibitory control disrupted healthy appetite regulation in taste preferences among ruminators, but not among non-ruminators. For eating behavior, the same interaction effect was significant when the two studies were combined. Inhibitory control disrupts healthy appetite regulation among ruminators. These findings suggest the need for caution in interventions that rely on inhibitory control, especially among samples with compulsive thought tendencies. © 2017 Wiley Periodicals, Inc.

RpoS plays a central role in the SOS induction by sub-lethal aminoglycoside concentrations in Vibrio cholerae.

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Baharoglu, Zeynep; Krin, Evelyne; Mazel, Didier

2013-01-01

Bacteria encounter sub-inhibitory concentrations of antibiotics in various niches, where these low doses play a key role for antibiotic resistance selection. However, the physiological effects of these sub-lethal concentrations and their observed connection to the cellular mechanisms generating genetic diversification are still poorly understood. It is known that, unlike for the model bacterium Escherichia coli, sub-minimal inhibitory concentrations (sub-MIC) of aminoglycosides (AGs) induce the SOS response in Vibrio cholerae. SOS is induced upon DNA damage, and since AGs do not directly target DNA, we addressed two issues in this study: how sub-MIC AGs induce SOS in V. cholerae and why they do not do so in E. coli. We found that when bacteria are grown with tobramycin at a concentration 100-fold below the MIC, intracellular reactive oxygen species strongly increase in V. cholerae but not in E. coli. Using flow cytometry and gfp fusions with the SOS regulated promoter of intIA, we followed AG-dependent SOS induction. Testing the different mutation repair pathways, we found that over-expression of the base excision repair (BER) pathway protein MutY relieved this SOS induction in V. cholerae, suggesting a role for oxidized guanine in AG-mediated indirect DNA damage. As a corollary, we established that a BER pathway deficient E. coli strain induces SOS in response to sub-MIC AGs. We finally demonstrate that the RpoS general stress regulator prevents oxidative stress-mediated DNA damage formation in E. coli. We further show that AG-mediated SOS induction is conserved among the distantly related Gram negative pathogens Klebsiella pneumoniae and Photorhabdus luminescens, suggesting that E. coli is more of an exception than a paradigm for the physiological response to antibiotics sub-MIC.

Urease and serine protease inhibitory alkaloids from Isatis tinctoria.

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Ahmad, Ijaz; Fatima, Itrat; Afza, Nighat; Malik, Abdul; Lodhi, Muhammad Arif; Choudhary, Muhammad Iqbal

2008-12-01

Phytochemical investigations on the alkaloidal fraction of the whole plant of the Isatis tinctoria led to the isolation of the alkaloids 1-6., 3'-Hydroxyepiglucoisatisin (3), Epiglucoisatisin (2) were found to be potent urease inhibitors in a concentration-dependent manner with IC(50) values 25.63 +/- 0.74, 37.01 +/- 0.41 and 31.72 +/- 0.93, 47.33 +/- 0.31 microM against Bacillus pasteurii & Jack bean urease, respectively. Compounds 3 and 2 also showed potent inhibitory potential against alpha-chymotrypsin with IC(50) values of 23.40 +/- 0.21 and 27.45 +/- 0.23 microM, respectively.

Quantitative evaluation of inhibitory effect of various substances on anaerobic ammonia oxidation (anammox).

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Nakamura, Tomotaka; Harigaya, Yuhki; Kimura, Yuya; Kuroiwa, Megumi; Kurata, Yuhri; Isaka, Kazuichi; Suwa, Yuichi

2017-09-01

The inhibitory effect of 20 substances of various chemical species on the anaerobic ammonia oxidation (anammox) activity of an enrichment culture, predominated by Candidatus Brocadia, was determined systematically by using a 15 N tracer technique. The initial anammox rate was determined during first 25 min with a small-scale anaerobic batch incubation supplemented with possible inhibitors. Although Cu 2+ and Mn 2+ did not inhibit anammox, the remaining 18 substances [Ni 2+ , Zn 2+ , Co 2+ , [Formula: see text] , Fe 2+ , 4 amines, ethylenediaminetetraacetic acid (EDTA), ethylenediamine-N,N'-bis (2-hydroxyphenylacetic acid) (EDDHA), citric acid, nitrilotriacetic acid (NTA), N,N-dimethylacetamide (DMA), 1,4-dioxane, dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF) and tetrahydrofuran (THF)] were inhibitory. Inhibitory effect of NTA, EDDHA, THF, DMF, DMA and amines on anammox was first determined in this study. Inhibitory effects of metals were re-evaluated because chelators, which may interfere inhibitory effect, have been used to dissolve metal salts into assay solution. The relative anammox activities as a function of concentration of each substance were described successfully (R 2  > 0.91) either with a linear inhibition model or with a Michaelis-Menten-based inhibition model. IC 50 values were estimated based on either model, and were compared. The IC 50 values of the 4 chelators (0.06-2.7 mM) and 5 metal ions (0.02-1.09 mM) were significantly lower than those of the 4 amines (10.6-29.1 mM) and 5 organic solvents (3.5-82 mM). Although it did not show any inhibition within 25 min, 0.1 mM Cu 2+ completely inhibited anammox activity in 240 min, suggesting that the inhibitory effect caused by Cu 2+ is time-dependent. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Flexible brain network reconfiguration supporting inhibitory control.

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Spielberg, Jeffrey M; Miller, Gregory A; Heller, Wendy; Banich, Marie T

2015-08-11

The ability to inhibit distracting stimuli from interfering with goal-directed behavior is crucial for success in most spheres of life. Despite an abundance of studies examining regional brain activation, knowledge of the brain networks involved in inhibitory control remains quite limited. To address this critical gap, we applied graph theory tools to functional magnetic resonance imaging data collected while a large sample of adults (n = 101) performed a color-word Stroop task. Higher demand for inhibitory control was associated with restructuring of the global network into a configuration that was more optimized for specialized processing (functional segregation), more efficient at communicating the output of such processing across the network (functional integration), and more resilient to potential interruption (resilience). In addition, there were regional changes with right inferior frontal sulcus and right anterior insula occupying more central positions as network hubs, and dorsal anterior cingulate cortex becoming more tightly coupled with its regional subnetwork. Given the crucial role of inhibitory control in goal-directed behavior, present findings identifying functional network organization supporting inhibitory control have the potential to provide additional insights into how inhibitory control may break down in a wide variety of individuals with neurological or psychiatric difficulties.

Voluntary inhibitory motor control over involuntary tic movements.

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Ganos, Christos; Rothwell, John; Haggard, Patrick

2018-03-06

Inhibitory control is crucial for normal adaptive motor behavior. In hyperkinesias, such as tics, disinhibition within the cortico-striato-thalamo-cortical loops is thought to underlie the presence of involuntary movements. Paradoxically, tics are also subject to voluntary inhibitory control. This puzzling clinical observation questions the traditional definition of tics as purely involuntary motor behaviors. Importantly, it suggests novel insights into tic pathophysiology. In this review, we first define voluntary inhibitory tic control and compare it with other notions of tic control from the literature. We then examine the association between voluntary inhibitory tic control with premonitory urges and review evidence linking voluntary tic inhibition to other forms of executive control of action. We discuss the somatotopic selectivity and the neural correlates of voluntary inhibitory tic control. Finally, we provide a scientific framework with regard to the clinical relevance of the study of voluntary inhibitory tic control within the context of the neurodevelopmental disorder of Tourette syndrome. We identify current knowledge gaps that deserve attention in future research. © 2018 International Parkinson and Movement Disorder Society. © 2018 International Parkinson and Movement Disorder Society.

Antifungal Effects of Zataria multiflora Essential Oil on the Inhibitory Growth of some Postharvest Pathogenic Fungi

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Mahboobeh NASSERI

2015-12-01

Full Text Available The present study aimed to determine minimum inhibitory concentration and minimum fungicidal concentration of the essential oil of Zataria multiflora to control Alternaria solani, Rhizoctonia solani, Rhizopus stolonifer, Aspergillus flavus, Aspergillus ochraceus and Aspergillus niger. The essential oil of Zataria multiflora was tested in vitro on PDA (malt extract agar medium with eight concentrations: 0, 10, 50, 100, 200, 300, 400, 500, 600, 700, 800, 900 and 1000 ppm. This investigation followed the completely randomized design (CRD with three replications. GC-MS evaluations of the essential oil revealed that thymol (35%, carvacrol (34%, cymene-p (9.89%, gamma-terpinene (5.88% and alpha-pinene (4.22% were the main compounds of Zataria multiflora oil. The results showed that the essential oil of Zataria multiflora has antifungal activity; the lowest inhibition (75% was observed in the A. niger, while the highest inhibition (95.3% was observed in A. solani. Minimum inhibitory concentration for A. solani, R. solani, R. stolonifer, A. flavus, A. ochraceus and A. niger was 200, 200, 200, 300, 300 and 200 ppm respectively. In addition, the present results showed that minimum fungicidal concentration (MFC for A. solani, R. solani, R .stolonifer, A. niger and A.ochraceus was 600, 400, 300, 900 and 700 ppm respectively and none of the tested concentrations were fatal for A. flavus. A. solani and R. solani showed a strong sensitivity to Zataria multiflora essential oil at all concentrations. Findings of the current study suggest that essential oils of Zataria multiflora could be used for control of postharvest phytopathogenic fungi on fruits or vegetables.

Inhibitory effect of vanillin on cellulase activity in hydrolysis of cellulosic biomass.

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Li, Yun; Qi, Benkun; Wan, Yinhua

2014-09-01

Pretreatment of lignocellulosic material produces a wide variety of inhibitory compounds, which strongly inhibit the following enzymatic hydrolysis of cellulosic biomass. Vanillin is a kind of phenolics derived from degradation of lignin. The effect of vanillin on cellulase activity for the hydrolysis of cellulose was investigated in detail. The results clearly showed that vanillin can reversibly and non-competitively inhibit the cellulase activity at appropriate concentrations and the value of IC50 was estimated to be 30 g/L. The inhibition kinetics of cellulase by vanillin was studied using HCH-1 model and inhibition constants were determined. Moreover, investigation of three compounds with similar structure of vanillin on cellulase activity demonstrated that aldehyde group and phenolic hydroxyl groups of vanillin had inhibitory effect on cellulase. These results provide valuable and detailed information for understanding the inhibition of lignin derived phenolics on cellulase. Copyright © 2014 Elsevier Ltd. All rights reserved.

A strain of Saccharomyces cerevisiae evolved for fermentation of lignocellulosic biomass displays improved growth and fermentative ability in high solids concentrations and in the presence of inhibitory compounds

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Hawkins Gary M

2011-11-01

Full Text Available Abstract Background Softwoods are the dominant source of lignocellulosic biomass in the northern hemisphere, and have been investigated worldwide as a renewable substrate for cellulosic ethanol production. One challenge to using softwoods, which is particularly acute with pine, is that the pretreatment process produces inhibitory compounds detrimental to the growth and metabolic activity of fermenting organisms. To overcome the challenge of bioconversion in the presence of inhibitory compounds, especially at high solids loading, a strain of Saccharomyces cerevisiae was subjected to evolutionary engineering and adaptation for fermentation of pretreated pine wood (Pinus taeda. Results An industrial strain of Saccharomyces, XR122N, was evolved using pretreated pine; the resulting daughter strain, AJP50, produced ethanol much more rapidly than its parent in fermentations of pretreated pine. Adaptation, by preculturing of the industrial yeast XR122N and the evolved strains in 7% dry weight per volume (w/v pretreated pine solids prior to inoculation into higher solids concentrations, improved fermentation performance of all strains compared with direct inoculation into high solids. Growth comparisons between XR122N and AJP50 in model hydrolysate media containing inhibitory compounds found in pretreated biomass showed that AJP50 exited lag phase faster under all conditions tested. This was due, in part, to the ability of AJP50 to rapidly convert furfural and hydroxymethylfurfural to their less toxic alcohol derivatives, and to recover from reactive oxygen species damage more quickly than XR122N. Under industrially relevant conditions of 17.5% w/v pretreated pine solids loading, additional evolutionary engineering was required to decrease the pronounced lag phase. Using a combination of adaptation by inoculation first into a solids loading of 7% w/v for 24 hours, followed by a 10% v/v inoculum (approximately equivalent to 1 g/L dry cell weight into 17

High Concentrations of Tranexamic Acid Inhibit Ionotropic Glutamate Receptors.

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Lecker, Irene; Wang, Dian-Shi; Kaneshwaran, Kirusanthy; Mazer, C David; Orser, Beverley A

2017-07-01

The antifibrinolytic drug tranexamic acid is structurally similar to the amino acid glycine and may cause seizures and myoclonus by acting as a competitive antagonist of glycine receptors. Glycine is an obligatory co-agonist of the N-methyl-D-aspartate (NMDA) subtype of glutamate receptors. Thus, it is plausible that tranexamic acid inhibits NMDA receptors by acting as a competitive antagonist at the glycine binding site. The aim of this study was to determine whether tranexamic acid inhibits NMDA receptors, as well as α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid and kainate subtypes of ionotropic glutamate receptors. Tranexamic acid modulation of NMDA, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid, and kainate receptors was studied using whole cell voltage-clamp recordings of current from cultured mouse hippocampal neurons. Tranexamic acid rapidly and reversibly inhibited NMDA receptors (half maximal inhibitory concentration = 241 ± 45 mM, mean ± SD; 95% CI, 200 to 281; n = 5) and shifted the glycine concentration-response curve for NMDA-evoked current to the right. Tranexamic acid also inhibited α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (half maximal inhibitory concentration = 231 ± 91 mM; 95% CI, 148 to 314; n = 5 to 6) and kainate receptors (half maximal inhibitory concentration = 90 ± 24 mM; 95% CI, 68 to 112; n = 5). Tranexamic acid inhibits NMDA receptors likely by reducing the binding of the co-agonist glycine and also inhibits α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid and kainate receptors. Receptor blockade occurs at high millimolar concentrations of tranexamic acid, similar to the concentrations that occur after topical application to peripheral tissues. Glutamate receptors in tissues including bone, heart, and nerves play various physiologic roles, and tranexamic acid inhibition of these receptors may contribute to adverse drug effects.

PTP1B inhibitory secondary metabolites from marine-derived fungal strains Penicillium spp. and Eurotium sp.

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Sohn, Jae Hak; Lee, Yu-Ri; Lee, Dong-Sung; Kim, Youn-Chul; Oh, Hyuncheol

2013-09-28

The selective inhibition of PTP1B has been widely recognized as a potential drug target for the treatment of type 2 diabetes and obesity. In the course of screening for PTP1B inhibitory fungal metabolites, the organic extracts of several fungal species isolated from marine environments were found to exhibit significant inhibitory effects, and the bioassay-guided investigation of these extracts resulted in the isolation of fructigenine A (1), cyclopenol (2), echinulin (3), flavoglaucin (4), and viridicatol (5). The structures of these compounds were determined mainly by analysis of NMR and MS data. These compounds inhibited PTP1B activity with 50% inhibitory concentration values of 10.7, 30.0, 29.4, 13.4, and 64.0 micrometer, respectively. Furthermore, the kinetic analysis of PTP1B inhibition by compounds 1 and 5 suggested that compound 1 inhibited PTP1B activity in a noncompetitive manner, whereas compound 5 inhibited PTP1B activity in a competitive manner.

In vivo hypotensive effect and in vitro inhibitory activity of some Cyperaceae species

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Monica Lacerda Lopes Martins

2013-12-01

Full Text Available In 1820, French naturalist August Saint Hillaire, during a visit in Espírito Santo (ES, a state in southeastern Brazil, reported a popular use of Cyperaceae species as antidote to snake bites. The plant may even have a hypotensive effect, though it was never properly researched. The in vitro inhibitory of the angiotensin converting enzyme (ACE activity of eigth ethanolic extracts of Cyperaceae was evaluated by colorimetric assay. Total phenolic and flavonoids were determined using colorimetric assay. The hypotensive effect of the active specie (Rhychonospora exaltata, ERE and the in vivo ACE assay was measured in vivo using male Wistar Kyoto (ERE, 0.01-100mg/kg, with acetylcholine (ACh as positive control (5 µg/kg, i.v.. The evaluation of ACE in vivo inhibitory effect was performed comparing the mean arterial pressure before and after ERE (10 mg/kg in animals which received injection of angiotensin I (ANG I; 0,03, 03 and 300 µg/kg, i.v.. Captopril (30 mg/kg was used as positive control. Bulbostylis capillaris (86.89 ± 15.20% and ERE (74.89 ± 11.95%, ERE were considered active in the in vitro ACE inhibition assay, at 100 µg/mL concentration. ACh lead to a hypotensive effect before and after ERE's curve (-40±5% and -41±3%. ERE showed a dose-dependent hypotensive effect and a in vivo ACE inhibitory effect. Cyperaceae species showed an inhibitory activity of ACE, in vitro, as well as high content of total phenolic and flavonoids. ERE exhibited an inhibitory effect on both in vitro and in vivo ACE. The selection of species used in popular medicine as antidotes, along with the in vitro assay of ACE inhibition, might be a biomonitoring method for the screening of new medicinal plants with hypotensive properties.

Inhibitory effect of Sphagnum palustre extract and its bioactive compounds on aromatase activity

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Hee Jeong Eom

2016-09-01

Full Text Available Sphagnum palustre (a moss has been traditionally used in Korea for the cure of several diseases such as cardiac pain and stroke. In this research, the inhibitory effect of S. palustre on aromatase (cytochrome P450 19, CYP19 activity was studied. [1β-3H] androstenedione was used as a substrate and incubated with S. palustre extract and recombinant human CYP19 in the presence of NADPH. S. palustre extract inhibited aromatase in a concentration-dependent manner (IC50 value: 36.4 ± 8.1 µg/mL. To elucidate the major compounds responsible for the aromatase inhibitory effects of S. palustre extract, nine compounds were isolated from the extract and tested for their inhibition of aromatase activity. Compounds 1, 6, and 7 displayed aromatase inhibition, while the inhibition by the other compounds was negligible.

Evaluation of phenolic profile, enzyme inhibitory and antimicrobial activities of Nigella sativa L. seed extracts

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Anela Topcagic

2017-11-01

Full Text Available Black cumin (Nigella sativa L. [N.sativa] seed extracts demonstrated numerous beneficial biological effects including, among others, antidiabetic, anticancer, immunomodulatory, antimicrobial, anti-inflammatory, antihypertensive, and antioxidant activity. To better understand the phytochemical composition of N. sativa seeds, methanol seed extracts were analyzed for phenolic acid and flavonoid content. Furthermore, we tested N. sativa methanol, n-hexane, and aqueous seed extracts for their inhibitory activity against butyrylcholinesterase (BChE and catalase (CAT as well as for antimicrobial activity against several bacterial and a yeast strains. The phenolic content of N. sativa was analyzed using ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS. The inhibition of BChE was assessed by modified Ellman’s method, and the inhibition of CAT was determined by monitoring hydrogen peroxide consumption. The extracts were tested against Bacillus subtilis, Staphylococcus aureus, Salmonella enterica, and Escherichia coli using the agar diffusion method. The UHPLC-MS/MS method allowed the identification and quantification of 23 phenolic compounds within 15 minutes. The major components found in N. sativa seed extract were sinapinic acid (7.22 ± 0.73 µg/mg as a phenolic acid and kaempferol (11.74 ± 0.92 µg/mg as a flavonoid. All extracts showed inhibitory activity against BChE, with methanol seed extract demonstrating the highest inhibitory activity (inhibitory concentration 50% [IC50] 79.11 ± 6.06 µg/ml. The methanol seed extract also showed strong inhibitory activity against CAT with an IC50 value of 6.61 ± 0.27 µg/ml. Finally, the methanol extract exhibited considerable inhibitory activity against the tested microbial strains. Overall, this is the first study to investigate the ability of black cumin seed extracts to inhibit CAT. Our results indicate that N. sativa seed can be considered as an effective inhibitor

Inhibitory Effect of Lactobacillus reuteri on Some Pathogenic Bacteria Isolated From Women With Bacterial Vaginosis

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Eslami

2014-08-01

Full Text Available Background Considering the high prevalence of bacterial vaginosis and its association with urinary tract infection in women and treatment of gynecologic problems occur when a high recurrence of bacterial vaginosis is often treated with antibiotics. Objectives The purpose of this study was to investigate the inhibitory effect of Lactobacillus reuteri on pathogenic bacteria isolated from women with bacterial vaginosis. Materials and Methods Ninety-six samples were obtained from vaginal discharge of women with bacterial vaginosis by a gynecologist with a Dacron swab and put in sterile tubes containing TSB broth and Thioglycollate broth. Then were immediately sent to the laboratory in cold chain for further assessment. Afterward, culture was transferred on blood agar, EMB, Palcam and differential diagnosis environments. Then cultures were incubated for 24 hours at 37 °C. Lactobacillus reuteri strains were cultured in MRS environment and transferred to laboratory. After purification of pathogenic bacteria, Lactobacillus reuteri inhibitory effect on pathogenic bacteria was evaluated by minimum inhibitory concentration (MIC and antibiogram. Statistical analysis was performed using SPSS software v.16. Results The results of this study demonstrated the inhibitory effect of Lactobacillus reuteri on some pathogenic bacteria that cause bacterial, including Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus saprophyticus, Streptococcus agalactiae, Enterococcus, Listeria monocytogenes and E. coli. Microscopic examination of stained smears of most Lactobacillus and pathogenic bacteria showed reduced. The prevalence of abnormal vaginal discharge, history of drug use, contraceptive methods and douching were 61%, 55%, 42% and 13%, respectively. Significant difference was observed between the use and non-use of IUD in women with bacterial. Conclusions Our findings indicated the inhibitory effect of Lactobacillus reuteri on pathogenic bacteria that

Isojacareubin from the Chinese Herb Hypericum japonicum: Potent Antibacterial and Synergistic Effects on Clinical Methicillin-Resistant Staphylococcus aureus (MRSA)

OpenAIRE

Zuo, Guo-Ying; An, Jing; Han, Jun; Zhang, Yun-Ling; Wang, Gen-Chun; Hao, Xiao-Yan; Bian, Zhong-Qi

2012-01-01

Through bioassay-guided fractionation of the extracts from the aerial parts of the Chinese herb Hypericum japonicum Thunb. Murray, Isojacareubin (ISJ) was characterized as a potent antibacterial compound against the clinical methicillin-resistant Staphylococcus aureus (MRSA). The broth microdilution assay was used to determine the minimal inhibitory concentrations (MICs) and minimal bactericidal concentrations (MBCs) of ISJ alone. The results showed t...

Ultrasonic extraction of polysaccharides from Laminaria japonica and their antioxidative and glycosidase inhibitory activities

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Wan, Peng; Yang, Xiaoman; Cai, Bingna; Chen, Hua; Sun, Huili; Chen, Deke; Pan, Jianyu

2015-08-01

In the present study, ultrasonic extraction technique (UET) is used to improve the yield of polysaccharides from Laminaria japonica (LJPs). And their antioxidative as well as glycosidase inhibitory activities are investigated. Box-Behnken design (BBD) combined with response surface methodology (RSM) is applied to optimize ultrasonic extraction for polysaccharides. The optimized conditions are obtained as extraction time at 54 min, ultrasonic power at 1050 W, extraction temperature at 80°C and ratio of material to solvent at 1:50 (g mL-1). Under these optimal ultrasonic extraction conditions, an actual experimental yield (5.75% ± 0.3%) is close to the predicted result (5.67%) with no significant difference ( P > 0.05). Vitro antioxidative and glycosidase inhibitory activities tests indicate that the crude polysaccharides (LJP) and two major ethanol precipitated fractions (LJP1 and LJP2) are in a concentration-dependent manner. LJP2 (30%-60% ethanol precipitated polysaccharides) possesses the strongest α-glucosidase inhibitory activity and moderate scavenging activity against hydroxyl radicals (66.09% ± 2.19%, 3.0 mg mL-1). Also, the inhibitory activity against α-glucosidase (59.08% ± 3.79%, 5.0 mg mL-1) is close to that of acarbose (63.99% ± 3.27%, 5.0 mg mL-1). LJP1 (30% ethanol precipitated polysaccharides) exhibits the strongest scavenging activity against hydroxyl radicals (99.80% ± 0.00%, 3.0 mg mL-1) and moderate α-glucosidase inhibitory activity (47.76% ± 1.92%, 5.0 mg mL-1). LJP shows the most remarkable DPPH scavenging activity (66.20% ± 0.11%, 5.0 mg mL-1) but weakest α-glucosidase inhibitory activity (37.77% ± 1.30%, 5.0 mg mL-1). However, all these LJPs exert weak inhibitory effects against α-amylase. These results show that UET is an effective method for extracting bioactive polysaccharides from seaweed materials. LJP1 and LJP2 can be developed as a potential ingredient in hypoglycemic agents or functional food for the management of

Leukaemia inhibitory factor--an exercise-induced myokine

DEFF Research Database (Denmark)

Broholm, Christa; Pedersen, Bente Klarlund

2010-01-01

During and following exercise skeletal muscle synthesises and releases a number of myokines that exert their effects either systemically or locally within the muscle. Several of these myokines influence metabolism, regeneration and/or hypertrophy and are therefore considered to be important...... to oscillations in intracellular Ca2+ concentrations. However, circulating levels of LIF are not increased with exercise suggesting that LIF exerts its effect locally. LIF stimulates muscle satellite cell proliferation and is involved in muscle hypertrophy and regeneration. Thus, LIF may be produced by skeletal...... contributing factors in muscle homeostasis and muscle adaptation to exercise training. Leukaemia inhibitory factor (LIF) is produced and released from muscle cells in vitro and from intact skeletal muscle in vivo. During exercise, skeletal muscle potently up-regulates LIF mRNA expression, likely due...

Angiotensin-I Converting Enzyme (ACE Inhibitory and Anti-Oxidant Activities of Sea Cucumber (Actinopyga lecanora Hydrolysates

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Raheleh Ghanbari

2015-12-01

Full Text Available In recent years, food protein-derived hydrolysates have received considerable attention because of their numerous health benefits. Amongst the hydrolysates, those with anti-hypertensive and anti-oxidative activities are receiving special attention as both activities can play significant roles in preventing cardiovascular diseases. The present study investigated the angiotensin-I converting enzyme (ACE inhibitory and anti-oxidative activities of Actinopyga lecanora (A. lecanora hydrolysates, which had been prepared by alcalase, papain, bromelain, flavourzyme, pepsin, and trypsin under their optimum conditions. The alcalase hydrolysate showed the highest ACE inhibitory activity (69.8% after 8 h of hydrolysis while the highest anti-oxidative activities measured by 2,2-diphenyl 1-1-picrylhydrazyl radical scavenging (DPPH (56.00% and ferrous ion-chelating (FIC (59.00% methods were exhibited after 24 h and 8 h of hydrolysis, respectively. The ACE-inhibitory and anti-oxidative activities displayed dose-dependent trends, and increased with increasing protein hydrolysate concentrations. Moreover, strong positive correlations between angiotensin-I converting enzyme (ACE inhibitory and anti-oxidative activities were also observed. This study indicates that A. lecanora hydrolysate can be exploited as a source of functional food owing to its anti-oxidant as well as anti-hypertension functions.

Self-reported impulsivity and inhibitory control in problem gamblers.

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Lorains, Felicity K; Stout, Julie C; Bradshaw, John L; Dowling, Nicki A; Enticott, Peter G

2014-01-01

Impulsivity is considered a core feature of problem gambling; however, self-reported impulsivity and inhibitory control may reflect disparate constructs. We examined self-reported impulsivity and inhibitory control in 39 treatment-seeking problem gamblers and 41 matched controls using a range of self-report questionnaires and laboratory inhibitory control tasks. We also investigated differences between treatment-seeking problem gamblers who prefer strategic (e.g., sports betting) and nonstrategic (e.g., electronic gaming machines) gambling activities. Treatment-seeking problem gamblers demonstrated elevated self-reported impulsivity, more go errors on the Stop Signal Task, and a lower gap score on the Random Number Generation task than matched controls. However, overall we did not find strong evidence that treatment-seeking problem gamblers are more impulsive on laboratory inhibitory control measures. Furthermore, strategic and nonstrategic problem gamblers did not differ from their respective controls on either self-reported impulsivity questionnaires or laboratory inhibitory control measures. Contrary to expectations, our results suggest that inhibitory dyscontrol may not be a key component for some treatment-seeking problem gamblers.

Tumor cell proliferation and cyclooxygenase inhibitory constituents in horseradish (Armoracia rusticana) and Wasabi (Wasabia japonica).

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Weil, Marvin J; Zhang, Yanjun; Nair, Muraleedharan G

2005-03-09

Cyclooxygenase and human tumor cell growth inhibitory extracts of horseradish (Armoracia rusticana) and wasabi (Wasabia japonica) rhizomes upon purification yielded active compounds 1-3 from horseradish and 4 and 5 from wasabi rhizomes. Spectroscopic analyses confirmed the identities of these active compounds as plastoquinone-9 (1), 6-O-acyl-beta-d-glucosyl-beta-sitosterol (2), 1,2-dilinolenoyl-3-galactosylglycerol (3), linolenoyloleoyl-3-beta-galactosylglycerol (4), and 1,2-dipalmitoyl-3-beta-galactosylglycerol (5). 3-Acyl-sitosterols, sinigrin, gluconasturtiin, and phosphatidylcholines isolated from horseradish and alpha-tocopherol and ubiquinone-10 from wasabi rhizomes isolated were inactive in our assays. At a concentration of 60 microg/mL, compounds 1 and 2 selectively inhibited COX-1 enzyme by 28 and 32%, respectively. Compounds 3, 4, and 5 gave 75, 42, and 47% inhibition of COX-1 enzyme, respectively, at a concentration of 250 microg/mL. In a dose response study, compound 3 inhibited the proliferation of colon cancer cells (HCT-116) by 21.9, 42.9, 51.2, and 68.4% and lung cancer cells (NCI-H460) by 30, 39, 44, and 71% at concentrations of 7.5, 15, 30, and 60 microg/mL, respectively. At a concentration of 60 microg/mL, compound 4 inhibited the growth of colon, lung, and stomach cancer cells by 28, 17, and 44%, respectively. This is the first report of the COX-1 enzyme and cancer cell growth inhibitory monogalactosyl diacylglycerides from wasabi and horseradish rhizomes.

Use of concentrated bone marrow aspirate and platelet rich plasma during minimally invasive decompression of the femoral head in the treatment of osteonecrosis.

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Martin, John R; Houdek, Matthew T; Sierra, Rafael J

2013-06-01

The aim of this paper is to describe our surgical procedure for the treatment of osteonecrosis of the femoral head using a minimally invasive technique. We have limited the use of this procedure for patients with pre-collapse osteonecrosis of the femoral head (Ficat Stage I or II). To treat osteonecrosis of the femoral head at our institution we currently use a combination of outpatient, minimally invasive iliac crest bone marrow aspirations and blood draw combined with decompressions of the femoral head. Following the decompression of the femoral head, adult mesenchymal stem cells obtained from the iliac crest and platelet rich plasma are injected into the area of osteonecrosis. Patients are then discharged from the hospital using crutches to assist with ambulation. This novel technique was utilized on 77 hips. Sixteen hips (21%) progressed to further stages of osteonecrosis, ultimately requiring total hip replacement. Significant pain relief was reported in 86% of patients (n=60), while the rest of patients reported little or no pain relief. There were no significant complications in any patient. We found that the use of a minimally invasive decompression augmented with concentrated bone marrow and platelet rich plasma resulted in significant pain relief and halted the progression of disease in a majority of patients.

Role of spinal inhibitory mechanisms in whiplash injuries.

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Lo, Yew-Long; Tan, Yam-Eng; Fook-Chong, Stephanie; Boolsambatra, Pensie; Yue, Wai-Mun; Chan, Ling-Ling; Tan, Seang-Beng

2007-06-01

Whiplash injury, commonly encountered in road traffic accidents, is a major cause of morbidity. Its pathophysiology is not well understood, and diagnosis remains clinical. Imaging and electrophysiological methods have not provided objective diagnostic evidence. Availability of a sensitive and specific diagnostic method would be of high clinical interest. We studied 20 consecutive patients with chronic whiplash injury. Despite persistent symptoms, most had minimal neurological findings. Cutaneous silent period (CSP), a nociceptive spinal inhibitory electromyographic reflex, showed 90% sensitivity and 90% specificity for its diagnosis. In contrast, only two patients (10%) had abnormal transcranial magnetic stimulation findings, and another two (10%) showed abnormal electromyography. Magnetic resonance imaging (MRI) showed cervical cord abnormalities in only two of 20 (10%) patients. None of the patients had abnormal somatosensory evoked potential studies. Our findings suggest that neurological dysfunction of whiplash may occur at several possible spinal cord localities in the CSP functional pathway. The use of this simple, quick, and sensitive method is advocated in the diagnostic work up of whiplash injury.

Inhibitory Activity of Artemisia spicigera Essential Oil Against Fungal Species Isolated From Minced Meat

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Ghajarbeygi

2015-11-01

Full Text Available Background Meat is an important source of several nutrients. The capability top of fresh meat to rot, causing the group of studies food science, biological and chemical stability meat consideration. Objectives This study was conducted to examine the inhibitory effect of Artemisias spicigera essential oil against fungal species isolated from minced meat. Materials and Methods Two types of media dichloran 18% glycerol (DG18 agar and dichloran rosebengal chloramphenicol (DRBC agar were selected for the mycological analysis of the minced meat samples. To evaluate the antifungal activity of essential oils, the microdilution broth method based on the CLSI (M27A guideline was used. Results Artemisias spicigera essential oil has an inhibitory effect on the growth of fungi found in samples of minced meat. Aspergillus, Penicillium and Cladosporium were the most common genera on both medium types. Average Minimum Inhibitory Concentration 50 = 1.88 µL/mL and MIC90 = 2 µL/mL were reported. The genus of Mucor with MIC = 1.0 µL/mL was the most sensitive and Aspergilus versicolor was the most resistant species to the essential oil with MIC = 4 µL/mL. Conclusions The results of the present study show a favorable inhibitory effect of Artemisias spicigera essential oil on fungal growth, especially Aspergillus species. According to the results, antifungal components of Artemisias spicigera in different forms are used to prevent fungal pollution.

In vitro Determination of Fungicide Inhibitory Concentration for Phakopsora pachyrhizi isolates

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Bianca Moura

2016-06-01

Full Text Available ABSTRACT In vitro assays were preformed to obtain the IC50 of eight fungicides against Phakopsora pachyrhizi isolates from Passo Fundo, RS, Ponta Grossa, PR, and Primavera do Leste, MT. Different concentrations of the fungicides were added to Petri dishes containing soybean leaf extract agar medium. One milliliter of P. pachyrhizi uredospore suspension at the concentration of 3.0 x 104 uredospores/mL was added to each dish for subsequent viability quantification. Only pyraclostrobin and the mixture trifloxystrobin + prothioconazole showed IC50 values inferior to 1.0 mg/L for all tested isolates, demonstrating high fungitoxicity. There was not loss of sensitivity to any of the tested fungicides.

Inhibitory effect of Zataria multiflora Boiss. essential oil, alone and in combination with monolaurin, on Listeria monocytogenes.

Science.gov (United States)

Raeisi, Mojtaba; Tajik, Hossein; Razavi Rohani, Seyed Mehdi; Tepe, Bektas; Kiani, Hossein; Khoshbakht, Rahem; Shirzad Aski, Hesamaddin; Tadrisi, Hamed

2016-01-01

Listeria monocytogenes is one of the major causes of infections in developing countries. In this study, chemical composition and anti-listerial effect of the essential oil of Zataria multiflora Boiss. alone and in combination with monolaurin were evaluated at different pH values (5, 6, and 7) and temperatures (5 ˚C and 30 ˚C). Chemical composition of Zataria multiflora Boiss. essential oil was evaluated by gas chromatography-mass spectrometry (GC-MS) analysis. Minimum inhibitory concentration (MIC) of the essential oil and monolaurin were determined using microbroth dilution method and the interactions of essential oil and monolaurin were determined by the evaluation of fractional inhibitory concentrations (FIC) index. Carvacrol (63.20%) and thymol (15.10%) were found as the main components of the essential oil. The MIC values of the oil and monolaurin at pH 7 and 30 ˚C were measured as 312.50 µg mL(-1) and 125.00 µg mL(-1), respectively. Combination of monolaurin and Z. multiflora essential oil were found to act synergistically (FIC index essential oil. The lowest MIC value of monolaurin and essential oil was observed at pH 5 and 5 ˚C. According to our results, the oil alone or in combination with monolaurin at low pH and temperature conditions showed a promising inhibitory effect on L. monocytogenes.

Novel modulatory effects of neurosteroids and benzodiazepines on excitatory and inhibitory neurons excitability: a multi-electrode array (MEA recording study"

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Giulia ePuia

2012-11-01

Full Text Available The balance between glutamate- and GABA-mediated neurotransmission in the brain is fundamental in the nervous system, but it is regulated by the ‘tonic’ release of a variety of endogenous factors. One such important group of molecules are the neurosteroids (NSs which, similarly to benzodiazepines (BDZs, enhance GABAergic neurotransmission. The purpose of our work was to investigate, at in-vivo physiologically relevant concentrations, the effects of NSs and BDZs as GABA modulators on dissociated neocortical neuron networks grown in long-term culture. We used a multi-electrode array (MEA recording technique and a novel analysis that was able to both identify the action potentials of engaged excitatory and inhibitory neurons and to detect drug-induced network up-states (burst. We found that the NSs tetrahydrodeoxycorticosterone (THDOC and allopregnanolone (ALLO applied at low nM concentrations, produced different modulatory effects on the two neuronal clusters. Conversely, at high concentrations (1 µM, both NSs, decreased excitatory and inhibitory neuron cluster excitability; however, even several hours after washout, the excitability of inhibitory neurons continued to be depressed, leading to a network long term depression (LTD. The BDZs clonazepam (CLZ and midazolam (MDZ also decreased the network excitability, but only MDZ caused LTD of inhibitory neuron cluster. To investigate the origin of the LTD after MDZ application, we tested finasteride (FIN, an inhibitor of endogenous NSs synthesis. FIN did not prevent the LTD induced by MDZ, but surprisingly induced it after application of CLZ. The significance and possible mechanisms underlying these LTD effects of NSs and BDZs are discussed. Taken together, our results not only demonstrate that ex-vivo networks show a sensitivity to NSs and BDZs comparable to that expressed in vivo, but also provide a new global in-vitro description that can help in understanding their activity in more complex

Recruitment of activation receptors at inhibitory NK cell immune synapses.

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Nicolas Schleinitz

2008-09-01

Full Text Available Natural killer (NK cell activation receptors accumulate by an actin-dependent process at cytotoxic immune synapses where they provide synergistic signals that trigger NK cell effector functions. In contrast, NK cell inhibitory receptors, including members of the MHC class I-specific killer cell Ig-like receptor (KIR family, accumulate at inhibitory immune synapses, block actin dynamics, and prevent actin-dependent phosphorylation of activation receptors. Therefore, one would predict inhibition of actin-dependent accumulation of activation receptors when inhibitory receptors are engaged. By confocal imaging of primary human NK cells in contact with target cells expressing physiological ligands of NK cell receptors, we show here that this prediction is incorrect. Target cells included a human cell line and transfected Drosophila insect cells that expressed ligands of NK cell activation receptors in combination with an MHC class I ligand of inhibitory KIR. The two NK cell activation receptors CD2 and 2B4 accumulated and co-localized with KIR at inhibitory immune synapses. In fact, KIR promoted CD2 and 2B4 clustering, as CD2 and 2B4 accumulated more efficiently at inhibitory synapses. In contrast, accumulation of KIR and of activation receptors at inhibitory synapses correlated with reduced density of the integrin LFA-1. These results imply that inhibitory KIR does not prevent CD2 and 2B4 signaling by blocking their accumulation at NK cell immune synapses, but by blocking their ability to signal within inhibitory synapses.

Antibiotic susceptibility of Brachyspira hyodysenteriae isolates from Czech swine farms: a 10-year follow-up study

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Josef Prášek

2014-01-01

Full Text Available Brachyspira hyodysenteriae is the causative agent of swine dysentery. Loss of clinical efficacy of some antimicrobial agents authorized for treating swine dysentery was observed on certain Czech pig farms. The aim of the present study was to evaluate the antimicrobial sensitivity of six antibiotics using a set of 202 randomly selected B. hyodysenteriae isolates obtained from farms in the Czech Republic between years 1997 and 2006. Minimum inhibitory concentration of antibiotics tylosin, lincomycin, tylvalosin, chlortetracyclin, tiamulin and valnemulin were tested, using an agar dilution method. All antibiotics tested showed an increase in minimal inhibitory concentrations. Continual decrease in susceptibility of B. hyodysenteriae isolates to tiamulin and valnemulin was observed. Multiresistant B. hyodysenteriae were isolated more frequently in the past years. Only a careful use of antibiotics can ensure their efficacy, especially in case of pleuromutilins, in the strategic therapy of swine dysentery. This rare study demonstrates the minimal inhibitory concentration changes of selected antidysenterics among Czech isolates of Brachyspira hyodysenteriae during a ten-year period.

Bilingual Contexts Modulate the Inhibitory Control Network

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Jing Yang

2018-03-01

Full Text Available The present functional magnetic resonance imaging (fMRI study investigated influences of language contexts on inhibitory control and the underlying neural processes. Thirty Cantonese–Mandarin–English trilingual speakers, who were highly proficient in Cantonese (L1 and Mandarin (L2, and moderately proficient in English (L3, performed a picture-naming task in three dual-language contexts (L1-L2, L2-L3, and L1-L3. After each of the three naming tasks, participants performed a flanker task, measuring contextual effects on the inhibitory control system. Behavioral results showed a typical flanker effect in the L2-L3 and L1-L3 condition, but not in the L1-L2 condition, which indicates contextual facilitation on inhibitory control performance by the L1-L2 context. Whole brain analysis of the fMRI data acquired during the flanker tasks showed more neural activations in the right prefrontal cortex and subcortical areas in the L2-L3 and L1-L3 condition on one hand as compared to the L1-L2 condition on the other hand, suggesting greater involvement of the cognitive control areas when participants were performing the flanker task in L2-L3 and L1-L3 contexts. Effective connectivity analyses displayed a cortical-subcortical-cerebellar circuitry for inhibitory control in the trilinguals. However, contrary to the right-lateralized network in the L1-L2 condition, functional networks for inhibitory control in the L2-L3 and L1-L3 condition are less integrated and more left-lateralized. These findings provide a novel perspective for investigating the interaction between bilingualism (multilingualism and inhibitory control by demonstrating instant behavioral effects and neural plasticity as a function of changes in global language contexts.

Antimicrobial activity of Diospyros melanoxylon bark from Similipal ...

African Journals Online (AJOL)

STORAGESEVER

2009-05-04

May 4, 2009 ... Phytomedicines have been an integral part of traditional .... inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of D. melanoxylon bark extracts on bacterial strains. S. aureusa. S. epidermidisa. B. licheniformisa. E. colia ... wrappers in the bidi (cigarette) industry (Mallavadhani et.

Effect of Carvacrol on Salmonella Saintpaul Biofilms on Stainless ...

African Journals Online (AJOL)

Purpose: To evaluate the effect of carvacrol against Salmonella Saintpaul biofilms on stainless steel surface. Methods: The effects of carvacrol on planktonic cells were evaluated by determining the minimum inhibitory concentration and minimal bactericidal concentration. The action of carvacrol on Salmonella Saintpaul ...

Decorrelation of Neural-Network Activity by Inhibitory Feedback

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Einevoll, Gaute T.; Diesmann, Markus

2012-01-01

Correlations in spike-train ensembles can seriously impair the encoding of information by their spatio-temporal structure. An inevitable source of correlation in finite neural networks is common presynaptic input to pairs of neurons. Recent studies demonstrate that spike correlations in recurrent neural networks are considerably smaller than expected based on the amount of shared presynaptic input. Here, we explain this observation by means of a linear network model and simulations of networks of leaky integrate-and-fire neurons. We show that inhibitory feedback efficiently suppresses pairwise correlations and, hence, population-rate fluctuations, thereby assigning inhibitory neurons the new role of active decorrelation. We quantify this decorrelation by comparing the responses of the intact recurrent network (feedback system) and systems where the statistics of the feedback channel is perturbed (feedforward system). Manipulations of the feedback statistics can lead to a significant increase in the power and coherence of the population response. In particular, neglecting correlations within the ensemble of feedback channels or between the external stimulus and the feedback amplifies population-rate fluctuations by orders of magnitude. The fluctuation suppression in homogeneous inhibitory networks is explained by a negative feedback loop in the one-dimensional dynamics of the compound activity. Similarly, a change of coordinates exposes an effective negative feedback loop in the compound dynamics of stable excitatory-inhibitory networks. The suppression of input correlations in finite networks is explained by the population averaged correlations in the linear network model: In purely inhibitory networks, shared-input correlations are canceled by negative spike-train correlations. In excitatory-inhibitory networks, spike-train correlations are typically positive. Here, the suppression of input correlations is not a result of the mere existence of correlations between

Free Radical Scavenging and Alpha/Beta-glucosidases Inhibitory Activities of Rambutan (Nephelium lappaceum L. Peel Extract

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Wahyu Widowati

2015-12-01

Full Text Available BACKGROUND: Diabetes mellitus (DM is associated with oxidative reaction and hyperglycemic condition. Human body has an antioxidant defense system toward free radical, but overproduction of free radical causing imbalance condition between the free radical and the antioxidant defense in the body that lead to several diseases, including DM. Glucosidase is an enzyme that hydrolize carbohydrates causing increase of blood glucose level, so by inhibiting this enzyme blood glucose level in plasma could be effectively decreased. Rambutan (Nephelium lappaceum L. peel has been reported to have many potential roles, such as antioxidant and anti-glycemia. Therefore our current study was conducted to evaluate possible effectivity of Rambutan peel to scavenge free radical and to inhibit α- and β-glucosidases. METHODS: Rambutan peel extraction (RPE was performed based on maceration method. Geraniin was used as control. For antioxidant study, 2,2-diphenyl-1- picrylhydrazyl (DPPH free radical scavenging test was performed. For glucosidase inhibitory activity study,  α- and β-glucosidases inhibitory activity tests were performed. Results were analyzed for median of Inhibitory Concentration (IC50. RESULTS: The scavenging activity of RPE was comparable with Geraniin. Meanwhile, the α-glucosidase inhibitory activity of RPE was higher than the one of Geraniin. The α-glucosidase-inhibitory-activity IC50 of RPE and Geraniin were 0.106±0.080 μg/ml and 16.12±0.29 μg/ml, respectively. The β-glucosidase inhibitory activity of RPE was also higher than the one of Geraniin. The β-glucosidase-inhibitory-activity IC50 of RPE and Geraniin were 7.02±0.99 μg/ml and 19.81±0.66 μg/ml, respectively. CONCLUSIONS: Since RPE showed comparable free radical scavenging activity with Geraniin and higher α- and β-glucosidases inhibitory activities than Geraniin, RPE could be suggested as a promising antioxidant and antiglycemic agent.  KEYWORDS

The minimally tuned minimal supersymmetric standard model

International Nuclear Information System (INIS)

Essig, Rouven; Fortin, Jean-Francois

2008-01-01

The regions in the Minimal Supersymmetric Standard Model with the minimal amount of fine-tuning of electroweak symmetry breaking are presented for general messenger scale. No a priori relations among the soft supersymmetry breaking parameters are assumed and fine-tuning is minimized with respect to all the important parameters which affect electroweak symmetry breaking. The superpartner spectra in the minimally tuned region of parameter space are quite distinctive with large stop mixing at the low scale and negative squark soft masses at the high scale. The minimal amount of tuning increases enormously for a Higgs mass beyond roughly 120 GeV

Somatostatin-expressing inhibitory interneurons in cortical circuits

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Iryna Yavorska

2016-09-01

Full Text Available Cortical inhibitory neurons exhibit remarkable diversity in their morphology, connectivity, and synaptic properties. Here, we review the function of somatostatin-expressing (SOM inhibitory interneurons, focusing largely on sensory cortex. SOM neurons also comprise a number of subpopulations that can be distinguished by their morphology, input and output connectivity, laminar location, firing properties, and expression of molecular markers. Several of these classes of SOM neurons show unique dynamics and characteristics, such as facilitating synapses, specific axonal projections, intralaminar input, and top-down modulation, which suggest possible computational roles. SOM cells can be differentially modulated by behavioral state depending on their class, sensory system, and behavioral paradigm. The functional effects of such modulation have been studied with optogenetic manipulation of SOM cells, which produces effects on learning and memory, task performance, and the integration of cortical activity. Different classes of SOM cells participate in distinct disinhibitory circuits with different inhibitory partners and in different cortical layers. Through these disinhibitory circuits, SOM cells help encode the behavioral relevance of sensory stimuli by regulating the activity of cortical neurons based on subcortical and intracortical modulatory input. Associative learning leads to long-term changes in the strength of connectivity of SOM cells with other neurons, often influencing the strength of inhibitory input they receive. Thus despite their heterogeneity and variability across cortical areas, current evidence shows that SOM neurons perform unique neural computations, forming not only distinct molecular but also functional subclasses of cortical inhibitory interneurons.

Plasma concentrations resulting from florfenicol preparations given to pigs in their drinking water.

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Gutiérrez, L; Vargas, D; Ocampo, L; Sumano, H; Martinez, R; Tapia, G

2011-09-01

Florfenicol administered through the drinking water has been recommended as a metaphylactic antibacterial drug to control outbreaks of respiratory diseases in pigs caused by strains of Actinobacillus pleuropneumoniae and Pasteurella multocida, yet it is difficult to pinpoint in practice when the drug is given metaphylactically or therapeutically. Further, pigs are likely to reject florfenicol-medicated water, and plasma concentrations of the drug are likely to be marginal for diseases caused by Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus. The reported minimal inhibitory concentration (MIC) values for these organisms show a breakpoint of 2 to 3 μg/mL. An experiment was conducted during September and October 2009. One hundred twenty healthy crossbred pigs (Landrace-Yorkshire), weighing 23 ± 6.2 kg, were used in this trial. They were randomly assigned to 5 groups, with 3 replicates of 8 animals/group. Two commercial preparations of florfenicol were administered through the drinking water at 2 concentrations (0.01 and 0.015%). Water intake was measured before and after medication, and plasma concentrations of florfenicol were determined by HPLC. Considerable rejection of florfenicol-medicated water was observed. However, plasma florfenicol concentrations were of a range sufficient for a methaphylaxis approach to preventing disease by bacteria, with MIC breakpoints of ≤ 0.25 μg/mL. Decreased efficacy as a metaphylactic medication should be expected for bacteria with MIC >0.25 μg/mL, considering the reported existence of bacteria resistant to florfenicol and the natural resistance of Streptococcus suis or E. coli to this drug.

Improved sulphate removal rates at increased sulphide concentration in the sulphidogenic bioreactor

CSIR Research Space (South Africa)

Greben, HA

2005-07-01

Full Text Available The product of the biological sulphate reduction is sulphide. High concentrations of molecular H2S(g) can be inhibitory for microbial activity, especially at a reactor pH of 6 to 7. This paper focuses on the effect of high sulphide concentrations...

Inhibitory effects of Oenothera biennis (evening primrose) seed extract on Streptococcus mutans and S. mutans-induced dental caries in rats.

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Matsumoto-Nakano, M; Nagayama, K; Kitagori, H; Fujita, K; Inagaki, S; Takashima, Y; Tamesada, M; Kawabata, S; Ooshima, T

2011-01-01

Oenothera biennis (evening primrose) seed extract (OBSE) is known to contain polyphenols, which may possess antioxidant activities. Polyphenols extracted from several plants are reported to exhibit cariostatic activities by inhibiting mutans streptococcus growth and glucosyltransferase activities. The purpose of the present study was to examine the inhibitory effects of OBSE on the development of dental caries, both in vitro and in vivo. OBSE was investigated for its inhibitory effects on cellular aggregation, hydrophobicity, sucrose-dependent adherence and insoluble glucan synthesis. Furthermore, biofilm formation was examined in the presence of OBSE, using confocal microscopic imaging. An animal experiment was also performed to examine the in vivo effects. OBSE induced a strong aggregation of Streptococcus mutans MT8148 cells, while cell surface hydrophobicity was decreased by approximately 90% at a concentration of 0.25 mg/ml. The sucrose-dependent adherence of the MT8148 cells was also reduced by addition of OBSE, with a reduction rate of 73% seen at a concentration of 1.00 mg/ml. Additionally, confocal microscopic observations revealed the biofilm development phase to be remarkably changed in the presence of OBSE. Furthermore, insoluble glucan synthesis was significantly reduced when OBSE was present at concentrations greater than 0.03 mg/ml. In an animal experiment, the caries scores in rats given OBSE (0.05 mg/ml in drinking water) were significantly lower than those in rats given water without OBSE. Our results indicate that OBSE has inhibitory activity on dental caries. 2011 S. Karger AG, Basel.

The minimal non-minimal standard model

International Nuclear Information System (INIS)

Bij, J.J. van der

2006-01-01

In this Letter I discuss a class of extensions of the standard model that have a minimal number of possible parameters, but can in principle explain dark matter and inflation. It is pointed out that the so-called new minimal standard model contains a large number of parameters that can be put to zero, without affecting the renormalizability of the model. With the extra restrictions one might call it the minimal (new) non-minimal standard model (MNMSM). A few hidden discrete variables are present. It is argued that the inflaton should be higher-dimensional. Experimental consequences for the LHC and the ILC are discussed

Do detour tasks provide accurate assays of inhibitory control?

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Whiteside, Mark A.; Laker, Philippa R.; Beardsworth, Christine E.

2018-01-01

Transparent Cylinder and Barrier tasks are used to purportedly assess inhibitory control in a variety of animals. However, we suspect that performances on these detour tasks are influenced by non-cognitive traits, which may result in inaccurate assays of inhibitory control. We therefore reared pheasants under standardized conditions and presented each bird with two sets of similar tasks commonly used to measure inhibitory control. We recorded the number of times subjects incorrectly attempted to access a reward through transparent barriers, and their latencies to solve each task. Such measures are commonly used to infer the differential expression of inhibitory control. We found little evidence that their performances were consistent across the two different Putative Inhibitory Control Tasks (PICTs). Improvements in performance across trials showed that pheasants learned the affordances of each specific task. Critically, prior experience of transparent tasks, either Barrier or Cylinder, also improved subsequent inhibitory control performance on a novel task, suggesting that they also learned the general properties of transparent obstacles. Individual measures of persistence, assayed in a third task, were positively related to their frequency of incorrect attempts to solve the transparent inhibitory control tasks. Neophobia, Sex and Body Condition had no influence on individual performance. Contrary to previous studies of primates, pheasants with poor performance on PICTs had a wider dietary breadth assayed using a free-choice task. Our results demonstrate that in systems or taxa where prior experience and differences in development cannot be accounted for, individual differences in performance on commonly used detour-dependent PICTS may reveal more about an individual's prior experience of transparent objects, or their motivation to acquire food, than providing a reliable measure of their inhibitory control. PMID:29593115

Activity of TDT 067 (Terbinafine in Transfersome) against Agents of Onychomycosis, as Determined by Minimum Inhibitory and Fungicidal Concentrations▿

Science.gov (United States)

Ghannoum, Mahmoud; Isham, Nancy; Herbert, Jacqueline; Henry, William; Yurdakul, Sam

2011-01-01

TDT 067 is a novel carrier-based dosage form (liquid spray) of 15 mg/ml of terbinafine in Transfersome that has been developed to deliver terbinafine to the nail bed to treat onychomycosis. In this study, we report the in vitro activities of TDT 067 against dermatophytes, compared with those of the Transfersome vehicle, naked terbinafine, and commercially available terbinafine (1%) spray. The MICs of TDT 067 and comparators against 25 clinical strains each of Trichophyton rubrum, T. mentagrophytes, and Epidermophyton floccosum were determined according to the CLSI M38–A2 susceptibility method (2008). Minimum fungicidal concentrations (MFCs) were determined by subculturing visibly clear wells from the MIC microtiter plates. TDT 067 demonstrated potent activity against the dermatophyte strains tested, with an MIC range of 0.00003 to 0.015 μg/ml. Overall, TDT 067 MIC50 values (defined as the lowest concentrations to inhibit 50% of the strains tested) were 8-fold and 60-fold lower than those of naked terbinafine and terbinafine spray, respectively. The Transfersome vehicle showed minimal inhibitory activity. TDT 067 demonstrated lower MFC values for T. rubrum and E. floccosum than naked terbinafine and terbinafine spray. TDT 067 has more potent antifungal activity against dermatophytes that cause nail infection than conventional terbinafine preparations. The Transfersome vehicle appears to potentiate the antifungal activity of terbinafine. Clinical investigation of TDT 067 for the topical treatment of onychomycosis is warranted. PMID:21411586

Organizers of inhibitory synapses come of age.

Science.gov (United States)

Krueger-Burg, Dilja; Papadopoulos, Theofilos; Brose, Nils

2017-08-01

While the postsynaptic density of excitatory synapses is known to encompass a highly complex molecular machinery, the equivalent organizational structure of inhibitory synapses has long remained largely undefined. In recent years, however, substantial progress has been made towards identifying the full complement of organizational proteins present at inhibitory synapses, including submembranous scaffolds, intracellular signaling proteins, transsynaptic adhesion proteins, and secreted factors. Here, we summarize these findings and discuss future challenges in assigning synapse-specific functions to the newly discovered catalog of proteins, an endeavor that will depend heavily on newly developed technologies such as proximity biotinylation. Further advances are made all the more essential by growing evidence that links inhibitory synapses to psychiatric and neurological disorders. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of multiple inhibitory components on anaerobic treatment processes in municipal solid waste incineration leachate.

Science.gov (United States)

Lei, Yuqing; Dang, Yan; Lan, Zhangheng; Sun, Dezhi

2016-06-01

This study served to investigate the comparative and combined effects of calcium, ammonia nitrogen, and aquatic humic substances (AHS) on specific methanogenic activity (SMA) in municipal solid waste leachate at mesophilic conditions. Using orthogonal experiments, anaerobic granular sludge was cultured with different concentrations combinations of the three added components for 13 days. The combination of 6000 mg/L calcium, 400 mg/L ammonia nitrogen, and 4000 mg/L AHS was the most inhibitory combination on the SMA of granular sludge, with a calculated 4.49 mL (standard temperature and atmospheric pressure) (STP) CH4/(gVSS·d) of SMA. The SMA with the addition of the inhibitory components was much lower than the control group's (1000 mg/L calcium, 200 mg/L ammonia nitrogen and 2000 mg/L AHS) with a calculated 12.97 mL (STP) CH4/(gVSS·d) of SMA. Calcium was the major inhibitor among the three components followed by AHS. High concentrations of calcium significantly inhibited the utilization of propionate and butyrate in the substrate and further affected the methanogenic process.

The Activity of Cotinus coggygria Scop. Leaves on Staphylococcus aureus Strains in Planktonic and Biofilm Growth Forms

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Katarína Rendeková

2015-12-01

Full Text Available The purpose of this study was to detect the effectiveness of Cotinus coggygria Scop. leaves methanol extract against planktonic and biofilm growth forms of Staphylococcus aureus. The antimicrobial activity was determined by the broth microdilution test. Minimal inhibitory concentrations and minimal bactericidal concentrations were detected against two collection and ten clinical S. aureus strains. Anti-biofilm activity of the tested extract was detected using 24 h bacterial biofilm on the surface of microtiter plate wells. The biofilm inhibitory activity was evaluated visually after 24 h interaction of extract with biofilm, and the eradicating activity by a regrowth method. The tested extract showed bactericidal activity against all S. aureus strains (methicillin susceptible or methicillin resistant in concentrations ranging from 0.313 to 0.625 mg·mL−1. Biofilm inhibitory concentrations were 10-times higher and biofilm eradicating concentrations 100-times higher (8 and 32 mg·mL−1, respectively. The phytochemical analysis of C. coggygria leaves 60% methanol extract performed by LC-DAD-MS/MS revealed quercetin rhamnoside, methyl gallate, and methyl trigallate as main constituents. Results of our study indicate that C. coggygria, rich in tannins and flavonoids, seems to be a prospective topical antibacterial agent with anti-biofilm activity.

[Evaluate drug interaction of multi-components in Morus alba leaves based on α-glucosidase inhibitory activity].

Science.gov (United States)

Ji, Tao; Su, Shu-Lan; Guo, Sheng; Qian, Da-Wei; Ouyang, Zhen; Duan, Jin-Ao

2016-06-01

Column chromatography was used for enrichment and separation of flavonoids, alkaloids and polysaccharides from the extracts of Morus alba leaves; glucose oxidase method was used with sucrose as the substrate to evaluate the multi-components of M. alba leaves in α-glucosidase inhibitory models; isobole method, Chou-Talalay combination index analysis and isobolographic analysis were used to evaluate the interaction effects and dose-effect characteristics of two components, providing scientific basis for revealing the hpyerglycemic mechanism of M. alba leaves. The components analysis showed that flavonoid content was 5.3%; organic phenolic acids content was 10.8%; DNJ content was 39.4%; and polysaccharide content was 18.9%. Activity evaluation results demonstrated that flavonoids, alkaloids and polysaccharides of M. alba leaves had significant inhibitory effects on α-glucosidase, and the inhibitory rate was increased with the increasing concentration. Alkaloids showed most significant inhibitory effects among these three components. Both compatibility of alkaloids and flavonoids, and the compatibility of alkaloids and polysaccharides demonstrated synergistic effects, but the compatibility of flavonoids and polysaccharides showed no obvious synergistic effects. The results have confirmed the interaction of multi-components from M. alba leaves to regulate blood sugar, and provided scientific basis for revealing hpyerglycemic effectiveness and mechanism of the multi-components from M. alba leaves. Copyright© by the Chinese Pharmaceutical Association.

Subminimal Inhibitory Concentrations of the Disinfectant Benzalkonium Chloride Select for a Tolerant Subpopulation of Escherichia coli with Inheritable Characteristics

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Solveig Langsrud

2012-03-01

Full Text Available Exposure of Escherichia coli to a subminimal inhibitory concentration (25% below MIC of benzalkonium chloride (BC, an antimicrobial membrane-active agent commonly used in medical and food-processing environments, resulted in cell death and changes in cell morphology (filamentation. A small subpopulation (1–5% of the initial population survived and regained similar morphology and growth rate as non-exposed cells. This subpopulation maintained tolerance to BC after serial transfers in medium without BC. To withstand BC during regrowth the cells up regulated a drug efflux associated gene (the acrB gene, member of the AcrAB-TolC efflux system and changed expression of outer membrane porin genes (ompFW and several genes involved in protecting the cell from the osmotic- and oxidative stress. Cells pre-exposed to osmotic- and oxidative stress (sodium chloride, salicylic acid and methyl viologen showed higher tolerance to BC. A control and two selected isolates showing increased BC-tolerance after regrowth in BC was genome sequenced. No common point mutations were found in the BC- isolates but one point mutation in gene rpsA (Ribosomal protein S1 was observed in one of the isolates. The observed tolerance can therefore not solely be explained by the observed point mutation. The results indicate that there are several different mechanisms responsible for the regrowth of a tolerant subpopulation in BC, both BC-specific and general stress responses, and that sub-MIC of BC may select for phenotypic variants in a sensitive E. coli culture.

Minocycline enhances inhibitory transmission to substantia gelatinosa neurons of the rat spinal dorsal horn.

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Peng, H-Z; Ma, L-X; Lv, M-H; Hu, T; Liu, T

2016-04-05

Minocycline, a second-generation tetracycline, is well known for its antibiotic, anti-inflammatory, and antinociceptive effects. Modulation of synaptic transmission is one of the analgesic mechanisms of minocycline. Although it has been reported that minocycline may suppress excitatory glutamatergic synaptic transmission, it remains unclear whether it could affect inhibitory synaptic transmission, which also plays a key role in modulating pain signaling. To examine the effect of minocycline on synaptic transmission in rat spinal substantia gelatinosa (SG) neurons, we recorded spontaneous inhibitory postsynaptic currents (sIPSCs) using whole-cell patch-clamp recording at a holding potential of 0 mV. Bath application of minocycline significantly increased the frequency but not the amplitude of sIPSCs in a reversible and concentration-dependent manner with an EC50 of 85. The enhancement of inhibitory synaptic transmission produced by minocycline was not affected by the glutamate receptor antagonists CNQX and D-APV or by the voltage-gated sodium channel blocker tetrodotoxin (TTX). Moreover, the potency of minocycline for facilitating sIPSC frequency was the same in both glycinergic and GABAergic sIPSCs without changing their decay phases. However, the facilitatory effect of minocycline on sIPSCs was eliminated in a Ca(2+)-free Krebs solution or by co-administration with calcium channel blockers. In summary, our data demonstrate that baseline inhibitory synaptic transmission in SG neurons is markedly enhanced by minocycline. This may function to decrease the excitability of SG neurons, thus leading to a modulation of nociceptive transmission. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Andrographolide sodium bisulphite-induced inactivation of urease: inhibitory potency, kinetics and mechanism.

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Mo, Zhi-Zhun; Wang, Xiu-Fen; Zhang, Xie; Su, Ji-Yan; Chen, Hai-Ming; Liu, Yu-Hong; Zhang, Zhen-Biao; Xie, Jian-Hui; Su, Zi-Ren

2015-07-16

The inhibitory effect of andrographolide sodium bisulphite (ASB) on jack bean urease (JBU) and Helicobacter pylori urease (HPU) was performed to elucidate the inhibitory potency, kinetics and mechanism of inhibition in 20 mM phosphate buffer, pH 7.0, 2 mM EDTA, 25 °C. The ammonia formations, indicator of urease activity, were examined using modified spectrophotometric Berthelot (phenol-hypochlorite) method. The inhibitory effect of ASB was characterized with IC50 values. Lineweaver-Burk and Dixon plots for JBU inhibition of ASB was constructed from the kinetic data. SH-blocking reagents and competitive active site Ni2+ binding inhibitors were employed for mechanism study. Molecular docking technique was used to provide some information on binding conformations as well as confirm the inhibition mode. The IC50 of ASB against JBU and HPU was 3.28±0.13 mM and 3.17±0.34 mM, respectively. The inhibition proved to be competitive and concentration- dependent in a slow-binding progress. The rapid formation of initial ASB-JBU complex with an inhibition constant of Ki=2.86×10(-3) mM was followed by a slow isomerization into the final complex with an overall inhibition constant of Ki*=1.33×10(-4) mM. The protective experiment proved that the urease active site is involved in the binding of ASB. Thiol reagents (L-cysteine and dithiothreithol) strongly protect the enzyme from the loss of enzymatic activity, while boric acid and fluoride show weaker protection, indicating that the active-site sulfhydryl group of JBU was potentially involved in the blocking process. Moreover, inhibition of ASB proved to be reversible since ASB-inactivated JBU could be reactivated by dithiothreitol application. Molecular docking assay suggested that ASB made contacts with the important sulfhydryl group Cys-592 residue and restricted the mobility of the active-site flap. ASB was a competitive inhibitor targeting thiol groups of urease in a slow-binding manner both reversibly and concentration

A pilot investigation of acute inhibitory control training in cocaine users.

Science.gov (United States)

Alcorn, Joseph L; Pike, Erika; Stoops, William S; Lile, Joshua A; Rush, Craig R

2017-05-01

Disrupted response inhibition and presence of drug-cue attentional bias in cocaine-using individuals have predicted poor treatment outcomes. Inhibitory control training could help improve treatment outcomes by strengthening cognitive control. This pilot study assessed the effects of acute inhibitory control training to drug- and non-drug-related cues on response inhibition performance and cocaine-cue attentional bias in cocaine-using individuals. Participants who met criteria for a cocaine-use disorder underwent five sessions of inhibitory control training to either non-drug-related cues (i.e., rectangles) or cocaine cues (n=10/condition) in a single day. Response inhibition and attentional bias were assessed prior to and following training using the stop-signal task and visual-probe task with eye tracking, respectively. Training condition groups did not differ on demographics, inhibitory control training performance, response inhibition, or cocaine-cue attentional bias. Response inhibition performance improved as a function of inhibitory control training in both conditions. Cocaine-cue attentional bias was observed, but did not change as a function of inhibitory control training in either condition. Response inhibition in cocaine-using individuals was augmented by acute inhibitory control training, which may improve treatment outcomes through better behavioral inhibition. Future studies should investigate longer-term implementation of inhibitory control training, as well as combining inhibitory control training with other treatment modalities. Copyright © 2017 Elsevier B.V. All rights reserved.

Inhibitory ability of children with developmental dyscalculia.

Science.gov (United States)

Zhang, Huaiying; Wu, Hanrong

2011-02-01

Inhibitory ability of children with developmental dyscalculia (DD) was investigated to explore the cognitive mechanism underlying DD. According to the definition of developmental dyscalculia, 19 children with DD-only and 10 children with DD&RD (DD combined with reading disability) were selected step by step, children in two control groups were matched with children in case groups by gender and age, and the match ratio was 1:1. Psychological testing software named DMDX was used to measure inhibitory ability of the subjects. The differences of reaction time in number Stroop tasks and differences of accuracy in incongruent condition of color-word Stroop tasks and object inhibition tasks between DD-only children and their controls reached significant levels (P<0.05), and the differences of reaction time in number Stroop tasks between dyscalculic and normal children did not disappear after controlling the non-executive components. The difference of accuracy in color-word incongruent tasks between children with DD&RD and normal children reached significant levels (P<0.05). Children with DD-only confronted with general inhibitory deficits, while children with DD&RD confronted with word inhibitory deficits only.

Minimalism

CERN Document Server

Obendorf, Hartmut

2009-01-01

The notion of Minimalism is proposed as a theoretical tool supporting a more differentiated understanding of reduction and thus forms a standpoint that allows definition of aspects of simplicity. This book traces the development of minimalism, defines the four types of minimalism in interaction design, and looks at how to apply it.

Antitubercular activity and inhibitory effect on Epstein-Barr virus activation of sterols and polyisoprenepolyols from an edible mushroom, Hypsizigus marmoreus.

Science.gov (United States)

Akihisa, Toshihiro; Franzblau, Scott Gary; Tokuda, Harukuni; Tagata, Masaaki; Ukiya, Motohiko; Matsuzawa, Tsunetomo; Metori, Koichi; Kimura, Yumiko; Suzuki, Takashi; Yasukawa, Ken

2005-06-01

Seven sterols (1-7) and eight polyisoprenepolyols (8-15), isolated from the non-saponifiable lipid fraction of the dichloromethane extract of an edible mushroom, Hypsizigus marmoreus (Buna-shimeji), were tested for their antitubercular activity against Mycobacterium tuberculosis strain H37Rv using the Microplate Alamar Blue Assay (MABA). Six sterols (2-7) and two polyisoprenepolyols (8, 12) showed a minimum inhibitory concentration (MIC) in the range of 1-51 microg/ml, while the others (1, 9-11, 13-15) were inactive (MIC>128 microg/ml). The seven sterols (1-7) and three polyisoprenepolyols (8, 10, 12) were further evaluated for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells. Sterols 6 and 7 showed potent inhibitory effects while preserving the high viability of Raji cells.

Inhibitory effects of drugs on the metabolic activity of mouse and human aldehyde oxidases and influence on drug-drug interactions.

Science.gov (United States)

Takaoka, Naoki; Sanoh, Seigo; Okuda, Katsuhiro; Kotake, Yaichiro; Sugahara, Go; Yanagi, Ami; Ishida, Yuji; Tateno, Chise; Tayama, Yoshitaka; Sugihara, Kazumi; Kitamura, Shigeyuki; Kurosaki, Mami; Terao, Mineko; Garattini, Enrico; Ohta, Shigeru

2018-04-17

As aldehyde oxidase (AOX) plays an emerging role in drug metabolism, understanding its significance for drug-drug interactions (DDI) is important. Therefore, we tested 10 compounds for species-specific and substrate-dependent differences in the inhibitory effect of AOX activity using genetically engineered HEK293 cells over-expressing human AOX1, mouse AOX1 or mouse AOX3. The IC 50 values of 10 potential inhibitors of the three AOX enzymes were determined using phthalazine and O 6 -benzylguanine as substrates. 17β-Estradiol, menadione, norharmane and raloxifene exhibited marked differences in inhibitory effects between the human and mouse AOX isoforms when the phthalazine substrate was used. Some of the compounds tested exhibited substrate-dependent differences in their inhibitory effects. Docking simulations with human AOX1 and mouse AOX3 were conducted for six representative inhibitors. The rank order of the minimum binding energy reflected the order of the corresponding IC 50 values. We also evaluated the potential DDI between an AOX substrate (O 6 -benzylguanine) and an inhibitor (hydralazine) using chimeric mice with humanized livers. Pretreatment of hydralazine increased the maximum plasma concentration (C max ) and the area under the plasma concentration-time curve (AUC 0-24 ) of O 6 -benzylguanine compared to single administration. Our in vitro data indicate species-specific and substrate-dependent differences in the inhibitory effects on AOX activity. Our in vivo data demonstrate the existence of a DDI which may be of relevance in the clinical context. Copyright © 2018 Elsevier Inc. All rights reserved.

High minimum inhibitory concentration of imipenem as a predictor of fatal outcome in patients with carbapenem non-susceptible Klebsiella pneumoniae.

Science.gov (United States)

Wu, Ping-Feng; Chuang, Chien; Su, Chin-Fang; Lin, Yi-Tsung; Chan, Yu-Jiun; Wang, Fu-Der; Chuang, Yin-Ching; Siu, L Kristopher; Fung, Chang-Phone

2016-09-02

Carbapenem resistance in Klebsiella pneumoniae is important because of its increasing prevalence and limited therapeutic options. To investigate the clinical and microbiological characteristics of patients infected or colonized with carbapenem non-susceptible K. pneumoniae (CnsKP) in Taiwan, we conducted a retrospective study at Taipei Veterans General Hospital from January 2012 to November 2013. Carbapenem non-susceptibility was defined as a minimum inhibitory concentration (MIC) of ≥2 mg/L for imipenem or meropenem. A total of 105 cases with CnsKP were identified: 49 patients with infection and 56 patients with colonization. Thirty-one isolates had genes that encoded carbapenemases (29.5%), including K. pneumoniae carbapenemase (KPC)-2 (n = 27), KPC-3 (n = 1), VIM-1 (n = 1) and IMP-8 (n = 2). The in-hospital mortality among patients with CnsKP was 43.8%. A MIC for imipenem ≥16 μg/mL, nasogastric intubation and Acute Physiology and Chronic Health Evaluation II score were independent risk factors for in-hospital mortality for all patients with CnsKP. A MIC for imipenem ≥16 μg/mL was also an independent risk factor for 14-day mortality in patients with CnsKP. In conclusion, a positive culture for CnsKP was associated with high in-hospital mortality. A high imipenem MIC of CnsKP can predispose a patient to a poor prognosis.

Antioxidant and lipase inhibitory activities and essential oil composition of pomegranate peel extracts.

Science.gov (United States)

Hadrich, Fatma; Cher, Slim; Gargouri, Youssef Talel; Adel, Sayari

2014-01-01

The chemical composition of essential oil, antioxidant and pancreatic lipase inhibitory activities of various solvent extracts obtained from pomegranate peelTunisian cultivar was evaluated. Gas chromatography/mass spectrometry was used to determine the composition of the PP essential oil. Nine-teen components were identified and the main compounds were the camphor (60.32%) and the benzaldehyde (20.98%). The phenolic and flavonoids content varied from 0 to 290.10 mg Gallic acid equivalent and from 5.2 to 20.43 mg catechin equivalent/g dried extract. The antioxidant activity of various solvent extracts from pomegranate peel was also investigated using various in vitro assays as the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical method, β-carotene bleaching and reducing power assays.Methanol and ethanol extracts showed the most potent antioxidant activity in all assays tested followed by water and acetone extracts. The inhibitory effect of the pomegranate peelextracts on porcine pancreatic lipase was evaluated and the results showed that ethanol and methanol extracts markedly reduced lipase activity. Generally, the highestlipase activity inhibitory (100%) was observed at a concentration of 1 mg/ml after 30 min of incubation. LC-MS analysis of ethanol extract showed the presence of four components which are cholorogenic acid, mannogalloylhexoside, gallic acid and ellagic acid. Our findings demonstrate that the ethanol extract from pomegranate peel might be a good candidate for furtherinvestigations of new bioactive substances.

Inhibitory effect of cyanide on nitrification process and its eliminating method in a suspended activated sludge process.

Science.gov (United States)

Han, Yuanyuan; Jin, Xibiao; Wang, Yuan; Liu, Yongdi; Chen, Xiurong

2014-02-01

Inhibition of nitrification by four typical pollutants (acrylonitrile, acrylic acid, acetonitrile and cyanide) in acrylonitrile wastewater was investigated. The inhibitory effect of cyanide on nitrification was strongest, with a 50% inhibitory concentration of 0.218 mg·gVSS-1 being observed in a municipal activated sludge system. However, the performance of nitrification was recovered when cyanide was completely degraded. The nitrification, which had been inhibited by 4.17 mg·gVSS-1 of free cyanide for 24 h, was recovered to greater than 95% of that without cyanide after 10 days of recovery. To overcome cyanide inhibition, cyanide-degrading bacteria were cultivated in a batch reactor by increasing the influent cyanide concentration in a stepwise manner, which resulted in an increase in the average cyanide degradation rate from 0.14 to 1.01 mg CN-·gVSS-1·h-1 over 20 days. The cultured cyanide-degrading bacteria were shaped like short rods, and the dominant cyanide-degrading bacteria strain was identified as Pseudomonas fluorescens NCIMB by PCR.

The α-amylase and α-glucosidase inhibitory effects of Irish seaweed extracts.

Science.gov (United States)

Lordan, Sinéad; Smyth, Thomas J; Soler-Vila, Anna; Stanton, Catherine; Ross, R Paul

2013-12-01

To date, numerous studies have reported on the antidiabetic properties of various plant extracts through inhibition of carbohydrate-hydrolysing enzymes. The objective of this research was to evaluate extracts of seaweeds for α-amylase and α-glucosidase inhibitory effects. Cold water and ethanol extracts of 15 seaweeds were initially screened and from this, five brown seaweed species were chosen. The cold water and ethanol extracts of Ascophyllum nodosum had the strongest α-amylase inhibitory effect with IC50 values of 53.6 and 44.7 μg/ml, respectively. Moreover, the extracts of Fucus vesiculosus Linnaeus were found to be potent inhibitors of α-glucosidase with IC50 values of 0.32 and 0.49 μg/ml. The observed effects were associated with the phenolic content and antioxidant activity of the extracts, and the concentrations used were below cytotoxic levels. Overall, our findings suggest that brown seaweed extracts may limit the release of simple sugars from the gut and thereby alleviate postprandial hyperglycaemia. Copyright © 2013. Published by Elsevier Ltd.

Inhibitory Effects of Spices on Biogenic Amine Accumulation during Fish Sauce Fermentation.

Science.gov (United States)

Zhou, Xuxia; Qiu, Mengting; Zhao, Dandan; Lu, Fei; Ding, Yuting

2016-04-01

The presence of high levels of biogenic amines is detrimental to the quality and safety of fish sauce. This study investigated the effects of ethanol extracts of spices, including garlic, ginger, cinnamon, and star anise extracts, in reducing the accumulation of biogenic amines during fish sauce fermentation. The concentrations of biogenic amines, which include histamine, putrescine, tyramine, and spermidine, all increased during fish sauce fermentation. When compared with the samples without spices, the garlic and star anise extracts significantly reduced these increases. The greatest inhibitory effect was observed for the garlic ethanolic extracts. When compared with controls, the histamine, putrescine, tyramine, and spermidine contents and the overall biogenic amine levels of the garlic extract-treated samples were reduced by 30.49%, 17.65%, 26.03%, 37.20%, and 27.17%, respectively. The garlic, cinnamon, and star anise extracts showed significant inhibitory effects on aerobic bacteria counts. Furthermore, the garlic and star anise extracts showed antimicrobial activity against amine producers. These findings may be helpful for enhancing the safety of fish sauce. © 2016 Institute of Food Technologists®

Two Novel Bioactive Peptides from Antarctic Krill with Dual Angiotensin Converting Enzyme and Dipeptidyl Peptidase IV Inhibitory Activities.

Science.gov (United States)

Ji, Wei; Zhang, Chaohua; Ji, Hongwu

2017-07-01

Inhibition of dipeptidyl peptidase IV (DPP-IV) and angiotensin converting enzyme (ACE) are considered useful in managing 2 often associated conditions: diabetes and hypertension. In this study, corolase PP was used to hydrolyze Antarctic krill protein. The hydrolysate (AKH) was isolated by ultrafiltration and purified by size-exclusion chromatography, ion exchange chromatography and reversed-phase high-performance liquid chromatography (RP-HPLC) sequentially. The in vitro inhibitory activities of all AKHs and several fractions obtained against ACE and DPP-IV were assessed. Two peptides, purified with dual-strength inhibitory activity against ACE and DPP-IV, were identified by TOF-MS/MS. Results indicated that not all fractions exhibited dual inhibitory activities of ACE and DPP-IV. The purified peptide Lys-Val-Glu-Pro-Leu-Pro had half-maximal inhibitory concentrations (IC 50 ) of 0.93±0.05 and 0.73±0.04 mg/mL against ACE and DPP-IV, respectively. The other peptide Pro-Ala-Leu had IC 50 values of 0.64±0.05 and 0.88±0.03 mg/mL against ACE and DPP-IV, respectively. This study firstly reported the sequences of dual bioactive peptides from Antarctic krill proteins, further provided new insights into the bioactive peptides responsible for the ACE and DPP-IV inhibitory activities from the Antarctic krill protein hydrolysate to manage hypertension and diabetes. © 2017 Institute of Food Technologists®.

POTENSI EKSTRAK RIMPANG KENCUR (Kaempferia galanga L. MENGHAMBAT PERTUMBUHAN Candida albicans

Directory of Open Access Journals (Sweden)

Annisa Rahmi

2016-12-01

Full Text Available Candida albicans infection is the cause of candidiasis. Candidiasis treatment can be done with a variety of antifungal drugs, one of them is rhizome of kencur (Kaempferia galanga L.. The Rhizome of kencur is selected as a traditional medicine because it contains chemical compounds such as flavonoids, tannins, saponins and essential oil that serves as an antifungal. This study aimed to determine the minimal inhibitory and minimal killing power and also an influence of kencur rhizome extract on the growth of Candida albicans in vitro. This research was true experimental design with posttest only control group design with tube dilution method. Results of Minimal Inhibitory Concentrations (MICs research showed there was no clarity at concentration of 20 mg/mL, 30 mg/mL, 40 mg/mL, and it shows clarity at concentration of 50 mg/mL and 60 mg/mL. Results of Minimum Bactericidal Concentrations (MBCs showed the number of colonies at concentration of 20 mg/mL were 84 colonies, concentration of 30 mg/mL were 48 colonies, concentration of 40 mg/mL were 27 colonies, concentration of mg/mL were 12 colonies and concentration of 60 mg/mL were 0 colony. Based on linear regression test, the result showed significance value of 0.000

Inhibition of growth and mycotoxins formation in moulds by marine ...

African Journals Online (AJOL)

... extracts (chloroform, hexane and methanol) had no activity on the microbial growth. Mycotoxins formation in Aspergillus flavus was inhibited by the ethanolic extracts at the concentration of 5%. Key Words: Algae, antimicrobial, minimal inhibitory concentration, moulds. African Journal of Biotechnology Vol.3(1) 2004: 71-75 ...

Optimization of a fermented pumpkin-based beverage to improve Lactobacillus mali survival and α-glucosidase inhibitory activity: A response surface methodology approach

Directory of Open Access Journals (Sweden)

W.Y. Koh

2018-03-01

Full Text Available The aim of this research was to develop an optimum fermentation and composition model for a new fermented pumpkin-based beverage with high probiotic survival and α-glucosidase inhibitory activity. Relationship between fermentation temperature, inoculum and ingredient concentration with response variables (fermentation time at the fermentation endpoint pH 4.5, survival rate of Lactobacillus mali K8 in pumpkin-based beverage treated with simulated gastrointestinal tract enzyme fluids, α-glucosidase inhibitory activity and sensory overall acceptability after 4 weeks of refrigerated storage was investigated using response surface methodology. Optimal formulation was obtained at an approximation of 40% pumpkin puree concentration, 8 Log CFU/mL inoculum and at 35 °C. The product derived from this optimum formula reached the fermentation endpoint after 28.34 ± 0.10 h and the quality change during 4 weeks storage was studied. The product achieved 88.56 ± 0.67% of L. mali survival after treatment with simulated gastric and intestinal juices; demonstrated 95.89 ± 0.30% α-glucosidase inhibitory activity, as well as scored 6.99 ± 0.40 on sensory overall acceptability after 4 weeks of storage. These findings illustrated that the model is effective in improving probiotic survival and α-glucosidase inhibitory activity with excellent sensory acceptability, thus may offer a dietary means for the management of hyperglycaemia. Keywords: Probiotics, Response surface methodology, Box-Behnken, Hyperglycaemia, Functional food

Minimization of stress concentration factor in cylindrical pressure vessels with ellipsoidal heads

International Nuclear Information System (INIS)

Magnucki, K.; Szyc, W.; Lewinski, J.

2002-01-01

The paper presents the problem of stress concentration in a cylindrical pressure vessel with ellipsoidal heads subject to internal pressure. At the line, where the ellipsoidal head is adjacent to the circular cylindrical shell, a shear force and bending moment occur, disturbing the membrane stress state in the vessel. The degree of stress concentration depends on the ratio of thicknesses of both the adjacent parts of the shells and on the relative convexity of the ellipsoidal head, with the range for radius-to-thickness ratio between 75 and 125. The stress concentration was analytically described and, afterwards, the effect of these values on the stress concentration ratio was numerically examined. Results of the analysis are shown on charts

Influence of vancomycin minimum inhibitory concentration on the treatment of methicillin-resistant Staphylococcus aureus bacteremia.

Science.gov (United States)

Soriano, Alex; Marco, Francesc; Martínez, José A; Pisos, Elena; Almela, Manel; Dimova, Veselka P; Alamo, Dolores; Ortega, Mar; Lopez, Josefina; Mensa, Josep

2008-01-15

Vancomycin treatment failure in methicillin-resistant Staphylococcus aureus (MRSA) bacteremia is not uncommon, even when MRSA is susceptible to vancomycin. The aim of our study was to evaluate whether vancomycin minimum inhibitory concentration has any influence on the mortality associated with MRSA bacteremia. A total of 414 episodes of MRSA bacteremia were prospectively followed-up from 1991 through 2005. MIC of vancomycin for the first isolate was determined by E-test. Clinical variables recorded were age, comorbidity, prior administration of vancomycin, use of corticosteroids, prognosis of underlying disease, source of bacteremia, the need for mechanical ventilation, shock, and mortality. A "treatment group" variable was created and defined as follows: (1) receipt of empirical vancomycin and an isolate with a vancomycin MIC of 1 microg/mL (38 episodes), (2) receipt of empirical vancomycin and an isolate with a vancomycin MIC of 1.5 microg/mL (90 episodes), (3) receipt of empirical vancomycin and an isolate with a vancomycin MIC of 2 microg/mL (40 episodes), and (4) receipt of inappropriate empirical therapy (246 episodes). Univariate and multivariate analyses were performed. Episodes caused by strains with a vancomycin MIC of 2 microg/mL were independently associated with a lower risk of shock (odds ratio [OR], 0.33; 95% confidence interval [CI], 0.15-0.75). Multivariate analysis selected receipt of empirical vancomycin and an isolate with a vancomycin MIC of 2 microg/mL (OR, 6.39; 95% CI, 1.68-24.3), receipt of inappropriate empirical therapy (OR, 3.62; 95% CI, 1.20-10.9), increasing age (OR, 1.02; 95% CI, 1.00-1.04), use of corticosteroids (OR, 1.85; 95% CI, 1.04-3.29), an ultimately (OR, 10.2; 95% CI, 2.85-36.8) or rapidly (OR, 1.81; 95% CI, 1.06-3.10) fatal underlying disease, high-risk (OR, 3.60; 95% CI, 1.89-6.88) and intermediate-risk (OR, 2.18; 95% CI, 1.17-4.04) sources of bacteremia, and shock (OR, 7.38; 95% CI, 4.11-13.3) as the best predictors of

Antibacterial Activity of Anthraquinone from Aloe on Spiced Pig Head

Science.gov (United States)

Xu, Lingyi; Li, Xiao; Cui, Yuqian; Pang, Meixia; Wang, Fang; Qi, Jinghua

2017-12-01

[Objective] To optimize the extraction of anthraquinone from Aloe by ultrasonic extraction and its antibacterialactivity. [Method]The influences of different extraction time and ethanol concentration, on anthraquinone contentwere evaluated by asingle factor experiment. And anthraquinone content was determined by ultraviolet spectrophotometry. The bacteriostasis of anthraquinone on spiced pig head’s common putrefying bacteria: Staphylococcus, Serratieae, Bacillus, Proteus and the minimal inhibitory concentration (MIC) were studied by oxford plate assay system. [Result]The best extraction time was 30 minutes and the best ethanol concentration was 80%. The antibacterial activity of the Aloe anthraquinone on Staphylococcus Aureus, Bacillus Proteus is obviously, the minimum inhibitory concentrations were 0.0625 g/mL, 0.05 g/mL, 0.125 g/mL respectively and no inhibitory effect on Serratieae. [Conclusions] The anthraquinones from Aloe can inhibit a part Of spoilage bacteria inspiced pig heads.

Minimal changes in health status questionnaires: distinction between minimally detectable change and minimally important change

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Knol Dirk L

2006-08-01

Full Text Available Abstract Changes in scores on health status questionnaires are difficult to interpret. Several methods to determine minimally important changes (MICs have been proposed which can broadly be divided in distribution-based and anchor-based methods. Comparisons of these methods have led to insight into essential differences between these approaches. Some authors have tried to come to a uniform measure for the MIC, such as 0.5 standard deviation and the value of one standard error of measurement (SEM. Others have emphasized the diversity of MIC values, depending on the type of anchor, the definition of minimal importance on the anchor, and characteristics of the disease under study. A closer look makes clear that some distribution-based methods have been merely focused on minimally detectable changes. For assessing minimally important changes, anchor-based methods are preferred, as they include a definition of what is minimally important. Acknowledging the distinction between minimally detectable and minimally important changes is useful, not only to avoid confusion among MIC methods, but also to gain information on two important benchmarks on the scale of a health status measurement instrument. Appreciating the distinction, it becomes possible to judge whether the minimally detectable change of a measurement instrument is sufficiently small to detect minimally important changes.

Determination of minimum inhibitory concentrations of itraconazole, terbinafine and ketoconazole against dermatophyte species by broth microdilution method.

Science.gov (United States)

Bhatia, V K; Sharma, P C

2015-01-01

Various antifungal agents both topical and systemic have been introduced into clinical practice for effectively treating dermatophytic conditions. Dermatophytosis is the infection of keratinised tissues caused by fungal species of genera Trichophyton, Epidermophyton and Microsporum, commonly known as dermatophytes affecting 20-25% of the world's population. The present study aims at determining the susceptibility patterns of dermatophyte species recovered from superficial mycoses of human patients in Himachal Pradesh to antifungal agents; itraconazole, terbinafine and ketoconazole. The study also aims at determining the minimum inhibitory concentrations (MICs) of these agents following the recommended protocol of Clinical and Laboratory Standards Institute (CLSI) (M38-A2). A total of 53 isolates of dermatophytes (T. mentagrophyte-34 in no., T. rubrum-18 and M. gypseum-1) recovered from the superficial mycoses were examined. Broth microdilution method M38-A2 approved protocol of CLSI (2008) for filamentous fungi was followed for determining the susceptibility of dermatophyte species. T. mentagrophyte isolates were found more susceptible to both itraconazole and ketoconazole as compared to terbinafine (MIC50: 0.125 µg/ml for itraconazole, 0.0625 µg/ml for ketoconazole and 0.5 µg/ml for terbinafine). Three isolates of T. mentagrophytes (VBS-5, VBSo-3 and VBSo-73) and one isolate of T. rubrum (VBPo-9) had higher MIC values of itraconazole (1 µg/ml). Similarly, the higher MIC values of ketoconazole were observed in case of only three isolates of T. mentagrophyte (VBSo-30 = 2 µg/ml; VBSo-44, VBM-2 = 1 µg/ml). The comparative analysis of the three antifungal drugs based on t-test revealed that 'itraconazole and terbinafine' and 'terbinafine and ketoconazole' were found independent based on the P terbinafine and ketoconazole'. The MIC values observed in the present study based on standard protocol M38-A2 of CLSI 2008 might serve as reference for further studies

Effect of in vitro irradiation and cell cycle-inhibitory drugs on the spontaneous human IgE synthesis in vitro

International Nuclear Information System (INIS)

Del Prete, G.F.; Vercelli, D.; Tiri, A.; Maggi, E.; Rossi, O.; Romagnani, S.; Ricci, M.

1987-01-01

The in vitro effects of radiation, diterpine forskolin (FK), and hydrocortisone (HC) on the in vitro spontaneous IgE synthesis by peripheral blood B-lymphocytes from atopic patients were investigated. Without affecting cell viability, in vitro irradiation inhibited in a dose-dependent fashion de novo IgE synthesis in vitro by B cells from all patients examined with a mean 40% reduction of in vitro IgE product after treatment with 100 rads. In contrast, the in vitro IgE production by the U266 myeloma cell line was unaffected, even by irradiation with 1600 rads. The addition to B cell cultures from atopic patients of FK consistently resulted in a dose-dependent inhibition of the spontaneous IgE production in vitro. The addition to cultures of 10(-5) and 10(-6) molar concentrations of HC was also usually inhibitory, whereas lower HC concentrations were uneffective or even enhanced the spontaneous in vitro IgE synthesis. When 10(-6) molar concentrations of both HC and FK were combined in culture, a summation inhibitory effect on the spontaneous IgE synthesis was observed. In contrast, neither FK nor HC had inhibitory effect on the in vitro spontaneous IgE synthesis by the U266 myeloma cell line. The spontaneous in vitro IgE synthesis by B cells from patients with Hodgkin's disease, demonstrating high levels of serum IgE, was strongly reduced or virtually abolished after patients underwent total nodal irradiation to prevent the spread of the disease. In addition, the in vitro spontaneous IgE synthesis by B cells from atopic patients was markedly decreased or abolished by in vivo administration of betamethasone

Antioxidant and Angiotensin-Converting Enzyme Inhibitory Activity of Eucalyptus camaldulensis and Litsea glaucescens Infusions Fermented with Kombucha Consortium.

Science.gov (United States)

Gamboa-Gómez, Claudia I; González-Laredo, Rubén F; Gallegos-Infante, José Alberto; Pérez, Mş Del Mar Larrosa; Moreno-Jiménez, Martha R; Flores-Rueda, Ana G; Rocha-Guzmán, Nuria E

2016-09-01

Physicochemical properties, consumer acceptance, antioxidant and angiotensin-converting enzyme (ACE) inhibitory activities of infusions and fermented beverages of Eucalyptus camaldulensis and Litsea glaucescens were compared. Among physicochemical parameters, only the pH of fermented beverages decreased compared with the unfermented infusions. No relevant changes were reported in consumer preference between infusions and fermented beverages. Phenolic profile measured by UPLC MS/MS analysis demonstrated significant concentration changes of these compounds in plant infusions and fermented beverages. Fermentation induced a decrease in the concentration required to stabilize 50% of DPPH radical ( i . e . lower IC 50 ). Additionally, it enhanced the antioxidant activity measured by the nitric oxide scavenging assay (14% of E. camaldulensis and 49% of L. glaucescens ); whereas relevant improvements in the fermented beverage were not observed in the lipid oxidation assay compared with unfermented infusions. The same behaviour was observed in the inhibitory activity of ACE; however, both infusions and fermented beverages had lower IC 50 than positive control (captopril). The present study demonstrated that fermentation has an influence on the concentration of phenolics and their potential bioactivity. E. camaldulensis and L. glaucescens can be considered as natural sources of biocompounds with antihypertensive potential used either as infusions or fermented beverages.

Antioxidant and Angiotensin-Converting Enzyme Inhibitory Activity of Eucalyptus camaldulensis and Litsea glaucescens Infusions Fermented with Kombucha Consortium

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Claudia I. Gamboa-Gómez

2016-01-01

Full Text Available Physicochemical properties, consumer acceptance, antioxidant and angiotensin-converting enzyme (ACE inhibitory activities of infusions and fermented beverages of Eucalyptus camaldulensis and Litsea glaucescens were compared. Among physicochemical parameters, only the pH of fermented beverages decreased compared with the unfermented infusions. No relevant changes were reported in consumer preference between infusions and fermented beverages. Phenolic profi le measured by UPLC MS/MS analysis demonstrated significant concentration changes of these compounds in plant infusions and fermented beverages. Fermentation induced a decrease in the concentration required to stabilize 50 % of DPPH radical (i.e. lower IC50. Additionally, it enhanced the antioxidant activity measured by the nitric oxide scavenging assay (14 % of E. camaldulensis and 49 % of L. glaucescens; whereas relevant improvements in the fermented beverage were not observed in the lipid oxidation assay compared with unfermented infusions. The same behaviour was observed in the inhibitory activity of ACE; however, both infusions and fermented beverages had lower IC50 than positive control (captopril. The present study demonstrated that fermentation has an influence on the concentration of phenolics and their potential bioactivity. E. camaldulensis and L. glaucescens can be considered as natural sources of biocompounds with antihypertensive potential used either as infusions or fermented beverages.

Myostatin inhibitory region of fish (Paralichthys olivaceus) myostatin-1 propeptide.

Science.gov (United States)

Lee, Sang Beum; Kim, Jeong Hwan; Jin, Deuk-Hee; Jin, Hyung-Joo; Kim, Yong Soo

2016-01-01

Myostatin (MSTN) is a potent negative regulator of skeletal muscle growth, and its activity is suppressed by MSTN propeptide (MSTNpro), the N-terminal part of MSTN precursor cleaved during post-translational MSTN processing. The current study examined which region of flatfish (Paralichthys olivaceus) MSTN-1 propeptide (MSTN1pro) is critical for MSTN inhibition. Six different truncated forms of MSTN1pro containing N-terminal maltose binding protein (MBP) as a fusion partner were expressed in Escherichia coli, and partially purified by an affinity chromatography for MSTN-inhibitory activity examination. Peptides covering different regions of flatfish MSTN1pro were also synthesized for MSTN-inhibitory activity examination. A MBP-fused MSTN1pro region consisting of residues 45-100 had the same MSTN-inhibitory potency as the full sequence flatfish MSTN1pro (residues 23-265), indicating that the region of flatfish MSTN1pro consisting of residues 45-100 is sufficient to maintain the full MSTN-inhibitory capacity. A MBP-fused MSTN1pro region consisting of residues 45-80 (Pro45-80) also showed MSTN-inhibitory activity with a lower potency, and the Pro45-80 demonstrated its MSTN binding capacity in a pull-down assay, indicating that the MSTN-inhibitory capacity of Pro45-80 is due to its binding to MSTN. Flatfish MSTN1pro synthetic peptides covering residues 45-65, 45-70, and 45-80 demonstrated MSTN-inhibitory activities, but not the synthetic peptide covering residues 45-54, indicating that residues 45-65 of flatfish MSTN1pro are essential for MSTN inhibition. In conclusion, current study show that like the mammalian MSTNpro, the MSTN-inhibitory region of flatfish MSTN1pro resides near its N-terminus, and imply that smaller sizes of MSTNpro can be effectively used in various applications designed for MSTN inhibition. Copyright © 2016 Elsevier Inc. All rights reserved.

Emergence of hyper-resistant Escherichia coli MG1655 derivative strains after applying sub-inhibitory doses of individual constituents of essential oils

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Beatriz eChueca

2016-03-01

Full Text Available The improvement of food preservation by using essential oils (EOs and their individual constituents (ICs is attracting enormous interest worldwide. Until now, researchers considered that treatments with such antimicrobial compounds did not induce bacterial resistance via a phenotypic (i.e. transient response. Nevertheless, the emergence of genotypic (i.e. stable resistance after treatment with these compounds had not been previously tested. Our results confirm that growth of Escherichia coli MG1655 in presence of sub-inhibitory concentrations of the ICs carvacrol, citral, and (+-limonene oxide do not increase resistance to further treatments with either the same IC (direct resistance or with other preservation treatments (cross-resistance such as heat or pulsed electric fields (PEF. Bacterial mutation frequency was likewise lower when those IC’s were applied; however, after 10 days of re-culturing cells in presence of sub-inhibitory concentrations of the ICs, we were able to isolate several derivative strains (i.e. mutants displaying an increased minimum inhibitory concentration to those ICs. Furthermore, when compared to the wild type (WT strain, they also displayed direct resistance and cross-resistance. Derivative strains selected with carvacrol and citral also displayed morphological changes involving filamentation along with cell counts at late-stationary growth phase that were lower than the WT strain. In addition, co-cultures of each derivative strain with the WT strain resulted in a predominance of the original strain in absence of ICs, indicating that mutants would not out-compete WT cells under optimal growth conditions. Nevertheless, growth in the presence of ICs facilitated the selection of these resistant mutants. Thus, as a result, subsequent food preservation treatments of these bacterial cultures might be less effective than expected for WT cultures. In conclusion, this study recommends that treatment with ICs at sub-inhibitory

Emergence of Hyper-Resistant Escherichia coli MG1655 Derivative Strains after Applying Sub-Inhibitory Doses of Individual Constituents of Essential Oils.

Science.gov (United States)

Chueca, Beatriz; Berdejo, Daniel; Gomes-Neto, Nelson J; Pagán, Rafael; García-Gonzalo, Diego

2016-01-01

The improvement of food preservation by using essential oils (EOs) and their individual constituents (ICs) is attracting enormous interest worldwide. Until now, researchers considered that treatments with such antimicrobial compounds did not induce bacterial resistance via a phenotypic (i.e., transient) response. Nevertheless, the emergence of genotypic (i.e., stable) resistance after treatment with these compounds had not been previously tested. Our results confirm that growth of Escherichia coli MG1655 in presence of sub-inhibitory concentrations of the ICs carvacrol, citral, and (+)-limonene oxide do not increase resistance to further treatments with either the same IC (direct resistance) or with other preservation treatments (cross-resistance) such as heat or pulsed electric fields (PEF). Bacterial mutation frequency was likewise lower when those IC's were applied; however, after 10 days of re-culturing cells in presence of sub-inhibitory concentrations of the ICs, we were able to isolate several derivative strains (i.e., mutants) displaying an increased minimum inhibitory concentration to those ICs. Furthermore, when compared to the wild type (WT) strain, they also displayed direct resistance and cross-resistance. Derivative strains selected with carvacrol and citral also displayed morphological changes involving filamentation along with cell counts at late-stationary growth phase that were lower than the WT strain. In addition, co-cultures of each derivative strain with the WT strain resulted in a predominance of the original strain in absence of ICs, indicating that mutants would not out-compete WT cells under optimal growth conditions. Nevertheless, growth in the presence of ICs facilitated the selection of these resistant mutants. Thus, as a result, subsequent food preservation treatments of these bacterial cultures might be less effective than expected for WT cultures. In conclusion, this study recommends that treatment with ICs at sub-inhibitory

Investigating the inhibitory effect of cyanide, phenol and 4-nitrophenol on the activated sludge process employed for the treatment of petroleum wastewater.

Science.gov (United States)

Inglezakis, V J; Malamis, S; Omirkhan, A; Nauruzbayeva, J; Makhtayeva, Z; Seidakhmetov, T; Kudarova, A

2017-12-01

In this work, the inhibitory effect of cyanide, phenol and 4-nitrophenol on the activated sludge process was investigated. The inhibition of the aerobic oxidation of organic matter, nitrification and denitrification were examined in batch reactors by measuring the specific oxygen uptake rate (sOUR), the specific ammonium uptake rate (sAUR) and the specific nitrogen uptake rate (sNUR) respectively. The tested cyanide, phenol and 4-nitrophenol concentrations were 0.2-1.7 mg/L, 4.8-73.1 mg/L and 8.2-73.0 mg/L respectively. Cyanide was highly toxic as it significantly (>50%) inhibited the activity of autotrophic biomass, heterotrophic biomass under aerobic conditions and denitrifiers even at relatively low concentrations (1.0-1.7 mgCN - /L). The determination of the half maximum inhibitory concentration (IC 50 ) confirmed this, since for cyanide IC 50 values were very low for the examined bioprocesses (25 mg/L) for the tested bioprocesses since appreciable concentrations were required to accomplish significant inhibition. The autotrophic bacteria were more sensitive to phenol than the aerobic heterotrophs. The denitrifiers were found to be very resistant to phenol. Copyright © 2016. Published by Elsevier Ltd.

Minimal surfaces

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Dierkes, Ulrich; Sauvigny, Friedrich; Jakob, Ruben; Kuster, Albrecht

2010-01-01

Minimal Surfaces is the first volume of a three volume treatise on minimal surfaces (Grundlehren Nr. 339-341). Each volume can be read and studied independently of the others. The central theme is boundary value problems for minimal surfaces. The treatise is a substantially revised and extended version of the monograph Minimal Surfaces I, II (Grundlehren Nr. 295 & 296). The first volume begins with an exposition of basic ideas of the theory of surfaces in three-dimensional Euclidean space, followed by an introduction of minimal surfaces as stationary points of area, or equivalently

Sodium-hydrogen exchanger inhibitory potential of Malus domestica, Musa × paradisiaca, Daucus carota, and Symphytum officinale.

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Verma, Vivek; Singh, Nirmal; Jaggi, Amteshwar Singh

2014-02-01

The involvement of sodium-hydrogen exchangers (NHE) has been described in the pathophysiology of diseases including ischemic heart and brain diseases, cardiomyopathy, congestive heart failure, epilepsy, dementia, and neuropathic pain. Synthetic NHE inhibitors have not achieved much clinical success; therefore, plant-derived phytoconstituents may be explored as NHE inhibitors. In the present study, the NHE inhibitory potential of hydroalcoholic and alkaloidal fractions of Malus domestica, Musa × paradisiaca, Daucus carota, and Symphytum officinale was evaluated. The different concentrations of hydroalcoholic and alkaloidal extracts of the selected plants were evaluated for their NHE inhibitory activity in the platelets using the optical swelling assay. Among the hydroalcoholic extracts, the highest NHE inhibitory activity was shown by M. domestica (IC50=2.350 ± 0.132 μg/mL) followed by Musa × paradisiaca (IC50=7.967 ± 0.451 μg/mL), D. carota (IC50=37.667 ± 2.517 μg/mL), and S. officinale (IC50=249.330 ± 1.155 μg/mL). Among the alkaloidal fractions, the highest NHE inhibitory activity was shown by the alkaloidal fraction of Musa × paradisiacal (IC50=0.010 ± 0.001 μg/mL) followed by D. carota (IC50=0.024 ± 0.002 μg/mL), M. domestica (IC50=0.031 ± 0.005 μg/mL), and S. officinale (IC50=4.233 ± 0.379 μg/mL). The IC50 of alkaloidal fractions was comparable to the IC50 of synthetic NHE inhibitor, EIPA [5-(N-ethyl-N-isopropyl)amiloride] (IC50=0.033 ± 0.004 μg/mL). It may be concluded that the alkaloidal fractions of these plants possess potent NHE inhibitory activity and may be exploited for their therapeutic potential in NHE activation-related pathological complications.

Starch Hydrolysis, Polyphenol Contents, and In Vitro Alpha Amylase Inhibitory Properties of Some Nigerian Foods As Affected by Cooking

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Sani Saidu

2017-12-01

Full Text Available The effect of cooking on starch hydrolysis, polyphenol contents, and in vitro α-amylase inhibitory properties of mushrooms (two varieties Russula virescens and Auricularia auricula-judae, sweet potato (Ipomea batatas, and potato (Solanum tuberosum was investigated. The total, resistant, and digestible starch contents of the raw and cooked food samples (FS ranged from 6.4 to 64.9; 0 to 10.1; and 6.4 to 62.7 g/100 g, respectively, while their percentages of starch digestibility (DS values expressed as percentages of total starch hydrolyzed ranged from 45.99 to 100. Raw and boiled unpeeled potato, raw and boiled peeled potato, raw A. auricula-judae, and sweet potato showed mild to high α-amylase inhibition (over a range of concentration of 10–50 mg/mL, which was lower than that of acarbose (that had 69% inhibition of α-amylase over a range of concentration of 2–10 mg/mL, unlike raw R. virescens, boiled A. auricula-judae, and boiled sweet potatoes that activated α-amylase and boiled R. virescens that gave 0% inhibition. The FS contained flavonoids and phenols in addition. The significant negative correlation (r = −0.55; P = 0.05 between the α-amylase inhibitory properties of the raw and cooked FS versus their SD indicates that the α-amylase inhibitors in these FS also influenced the digestibility of their starches. In addition, the significant positive correlation between the α-amylase inhibitory properties of the raw and cooked FS versus their resistant starch (RS (r = 0.59; P = 0.01 contents indicates that the RS constituents of these FS contributed to their α-amylase inhibitory properties. The study showed the usefulness of boiled unpeeled potato, boiled potato peeled, and raw sweet potato as functional foods for people with type 2 diabetes.

Metabolites with Gram-negative bacteria quorum sensing inhibitory activity from the marine animal endogenic fungus Penicillium sp. SCS-KFD08.

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Kong, Fan Dong; Zhou, Li Man; Ma, Qing Yun; Huang, Sheng Zhuo; Wang, Pei; Dai, Hao Fu; Zhao, You Xing

2017-01-01

Three new compounds named penicitor A, aculene E and penicitor B, as well as four known compounds, were isolated from the fermentation broth of Penicillium sp. SCS-KFD08 associated with a marine animal Sipunculus nudus from the Haikou bay of China. Their planar structures and absolute configurations were unambiguously elucidated by spectroscopic data, Mosher's method, CD spectrum analysis along with quantum ECD calculation. Among them, compounds 2-7 showed quorum sensing inhibitory activity against Chromobacterium violaceum CV026, and could significantly reduce violacein production in N-hexanoyl-l-homoserine lactone (C6-HSL) induced C. violaceum CV026 cultures at sub-inhibitory concentrations.

Comparison of the inhibitory effects of tolcapone and entacapone against human UDP-glucuronosyltransferases

Energy Technology Data Exchange (ETDEWEB)

Lv, Xia [Laboratory of Pharmaceutical Resource Discovery, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); State Key Laboratory of Organ Failure Research, Guangdong Provincial Institute of Nephrology, Southern Medical University, Guangzhou 510515 (China); Wang, Xin-Xin [RSKT Biopharma Inc., Dalian 116023 (China); Hou, Jie [Dalian Medical University, Dalian 116044 (China); Fang, Zhong-Ze [RSKT Biopharma Inc., Dalian 116023 (China); Wu, Jing-Jing [Laboratory of Pharmaceutical Resource Discovery, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); State Key Laboratory of Organ Failure Research, Guangdong Provincial Institute of Nephrology, Southern Medical University, Guangzhou 510515 (China); Cao, Yun-Feng [RSKT Biopharma Inc., Dalian 116023 (China); Liu, Shu-Wen [State Key Laboratory of Organ Failure Research, Guangdong Provincial Institute of Nephrology, Southern Medical University, Guangzhou 510515 (China); Ge, Guang-Bo, E-mail: geguangbo@dicp.ac.cn [Laboratory of Pharmaceutical Resource Discovery, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); State Key Laboratory of Organ Failure Research, Guangdong Provincial Institute of Nephrology, Southern Medical University, Guangzhou 510515 (China); Yang, Ling, E-mail: ylingdicp@gmail.com [Laboratory of Pharmaceutical Resource Discovery, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Jiangxi University of Traditional Chinese Medicine, Nanchang 330006 (China)

2016-06-15

Tolcapone and entacapone are two potent catechol-O-methyltransferase (COMT) inhibitors with a similar skeleton and displaying similar pharmacological activities. However, entacapone is a very safe drug used widely in the treatment of Parkinson's disease, while tolcapone is only in limited use for Parkinson's patients and needs careful monitoring of hepatic functions due to hepatotoxicity. This study aims to investigate and compare the inhibitory effects of entacapone and tolcapone on human UDP-glucosyltransferases (UGTs), as well as to evaluate the potential risks from the view of drug-drug interactions (DDI). The results demonstrated that both tolcapone and entacapone exhibited inhibitory effects on UGT1A1, UGT1A7, UGT1A9 and UGT1A10. In contrast to entacapone, tolcapone exhibited more potent inhibitory effects on UGT1A1, UGT1A7, and UGT1A10, while their inhibitory potentials against UGT1A9 were comparable. It is noteworthy that the inhibition constants (K{sub i}) of tolcapone and entacapone against bilirubin-O-glucuronidation in human liver microsomes (HLM) are determined as 0.68 μM and 30.82 μM, respectively, which means that the inhibition potency of tolcapone on UGT1A1 mediated bilirubin-O-glucuronidation in HLM is much higher than that of entacapone. Furthermore, the potential risks of tolcapone or entacapone via inhibition of human UGT1A1 were quantitatively predicted by the ratio of the areas under the plasma drug concentration-time curve (AUC). The results indicate that tolcapone may result in significant increase in AUC of bilirubin or the drugs primarily metabolized by UGT1A1, while entacapone is unlikely to cause a significant DDI through inhibition of UGT1A1. - Highlights: • Tolcapone and entacapone exhibited preferential inhibition against UGT1A enzymes. • In contrast to entacapone, tolcapone exhibited more potent inhibitory effects on human UGT1A1, 1 A7 and 1 A10. • Tolcapone may lead to significant increase in AUC of bilirubin. �

Detection of the pyrogen in the radiopharmaceuticals using Limulus test and inhibitory factors in the gelation reaction

International Nuclear Information System (INIS)

Murata, Hajime; Iio, Masahiro; Yamada, Hideo; Chiba, Kazuo; Kobayashi, Masayoshi.

1975-01-01

To examine the sensitivities of the Limulus test and the inhibitory factors in radiopharmaceuticals, the following procedures were employed. Twenty commonly used radiopharmaceuticals were examined by Limulus Lysate (Pre-gel). In order to detect the inhibitory factors, several doses of endotoxin (E. coli) were added to the radiopharmaceuticals before the Limulus test was made and the results were compared with control results using saline solution of endotoxin. When the pH of the reaction solution lay out of a suitable range (6.0-7.5), the pH was adjusted by Tris-HCl buffer before the reaction. The sensitivity of the Limulus test control using Pre-gel was positive at a concentration of 10 -3 μg/ml of endotoxin. The Limulus test was sensitive and without inhibitory reactions for sup(99m)TcO 4 -, sup(99m)Tc-albumin, sup(99m)Tc-MAA, sup(99m)Tc-Sn-colloid, 131 I-hippurate, Na 131 I, Na 2 51 CrO 4 , 67 Ga-citrate and 57 Co-bleomycin as they were supplied. 111 In-DTPA, sup(99m)Tc-phytate, sup(99m)Tc-pyrophosphate, sup(99m)Tc-DTPA, 131 I-PVP, 59 FeCl 3 , Na-phosphate ( 32 P), 198 Au-colloid and 75 Se-selenomethionine needed to have their pH adjusted to avoid inhibition. Benzyl alcohol in the radiopharmaceutical showed an inhibitory effect at a concentration greater than 1%. Commonly used 169 Yb-DTPA which was evaluated by this test had a sensitivity of 2.5 x 10 -3 μg/ml due to addition of a small amount of benzyl alcohol. 131 I-BSP showed intense inhibition in gelation reaction. Contaminations of endotoxin were detected in sup(99m)Tc-albumin, sup(99m)Tc-Sn-colloid, 131 I-hippurate, Na 131 I, Na 2 51 CrO 4 , 198 Au-colloid, 57 Co-bleomycin and 75 Se-selenomethionine. (auth.)

Angiotensin I-Converting-Enzyme-Inhibitory and Antibacterial Peptides from Lactobacillus helveticus PR4 Proteinase-Hydrolyzed Caseins of Milk from Six Species

Science.gov (United States)

Minervini, F.; Algaron, F.; Rizzello, C. G.; Fox, P. F.; Monnet, V.; Gobbetti, M.

2003-01-01

Sodium caseinates prepared from bovine, sheep, goat, pig, buffalo or human milk were hydrolyzed by a partially purified proteinase of Lactobacillus helveticus PR4. Peptides in each hydrolysate were fractionated by reversed-phase fast-protein liquid chromatography. The fractions which showed the highest angiotensin I-converting-enzyme (ACE)-inhibitory or antibacterial activity were sequenced by mass spectrum and Edman degradation analyses. Various ACE-inhibitory peptides were found in the hydrolysates: the bovine αS1-casein (αS1-CN) 24-47 fragment (f24-47), f169-193, and β-CN f58-76; ovine αS1-CN f1-6 and αS2-CN f182-185 and f186-188; caprine β-CN f58-65 and αS2-CN f182-187; buffalo β-CN f58-66; and a mixture of three tripeptides originating from human β-CN. A mixture of peptides with a C-terminal sequence, Pro-Gly-Pro, was found in the most active fraction of the pig sodium caseinate hydrolysate. The highest ACE-inhibitory activity of some peptides corresponded to the concentration of the ACE inhibitor (S)-N-(1-[ethoxycarbonyl]-3-phenylpropyl)-ala-pro maleate (enalapril) of 49.253 μg/ml (100 μmol/liter). Several of the above sequences had features in common with other ACE-inhibitory peptides reported in the literature. The 50% inhibitory concentration (IC50) of some of the crude peptide fractions was very low (16 to 100 μg/ml). Some identified peptides were chemically synthesized, and the ACE-inhibitory activity and IC50s were confirmed. An antibacterial peptide corresponding to β-CN f184-210 was identified in human sodium caseinate hydrolysate. It showed a very large spectrum of inhibition against gram-positive and -negative bacteria, including species of potential clinical interest, such as Enterococcus faecium, Bacillus megaterium, Escherichia coli, Listeria innocua, Salmonella spp., Yersinia enterocolitica, and Staphylococcus aureus. The MIC for E. coli F19 was ca. 50 μg/ml. Once generated, the bioactive peptides were resistant to further

Residential Mobility, Inhibitory Control, and Academic Achievement in Preschool

Science.gov (United States)

Schmitt, Sara A.; Finders, Jennifer K.; McClelland, Megan M.

2015-01-01

Research Findings: The present study investigated the direct effects of residential mobility on children's inhibitory control and academic achievement during the preschool year. It also explored fall inhibitory control and academic skills as mediators linking residential mobility and spring achievement. Participants included 359 preschool children…

Inhibitory effect and mode of action of chitosan solution against rice bacterial brown stripe pathogen Acidovorax avenae subsp. avenae RS-1.

Science.gov (United States)

Yang, Chunlan; Li, Bin; Ge, Mengyu; Zhou, Kaile; Wang, Yanli; Luo, Ju; Ibrahim, Muhammad; Xie, Guanlin; Sun, Guochang

2014-06-04

Inhibitory effect and mode of action of chitosan solution against rice bacterial brown stripe pathogen Acidovorax avenae subsp. avenae (Aaa) strain RS-1 was examined in this study. Result from this study indicated that chitosan solutions at 0.10, 0.20, and 0.40mg/mL inhibited the in vitro growth of Aaa strain RS-1, and in general the inhibitory efficiency increased with the increase of both chitosan concentration and the incubation time. Antibacterial activity of chitosan in this study may be mainly due to the damage of cell membrane, which was evidenced by both the cell lysis observed by transmission electron microscopy, and the increased release of cell materials based on the measurement of cell membrane integrity. Furthermore, chitosan solutions at concentrations of 0.1, 0.2, and 0.4mg/mL markedly inhibited bacterial biofilm formation compared to the control, and the inhibitory effect increased with the increase of chitosan concentration. In addition, quantitative real-time PCR of the 10 secretion system related genes revealed the differential expression of genes in particular ompA/motB, emphasizing the importance of this gene in the response of Aaa strain RS-1 to chitosan stress. These results indicated that the antibacterial mode of action of chitosan may be mainly due to membrane disruption and lysis, reduction of biofilm formation, and gene expression change. Overall, the results clearly indicated that chitosan had the potential to control bacterial brown stripe of rice. Copyright © 2014 Elsevier Ltd. All rights reserved.

Replica Approach for Minimal Investment Risk with Cost

Science.gov (United States)

Shinzato, Takashi

2018-06-01

In the present work, the optimal portfolio minimizing the investment risk with cost is discussed analytically, where an objective function is constructed in terms of two negative aspects of investment, the risk and cost. We note the mathematical similarity between the Hamiltonian in the mean-variance model and the Hamiltonians in the Hopfield model and the Sherrington-Kirkpatrick model, show that we can analyze this portfolio optimization problem by using replica analysis, and derive the minimal investment risk with cost and the investment concentration of the optimal portfolio. Furthermore, we validate our proposed method through numerical simulations.

Inhibitory Effect of Crizotinib on Creatinine Uptake by Renal Secretory Transporter OCT2.

Science.gov (United States)

Arakawa, Hiroshi; Omote, Saki; Tamai, Ikumi

2017-09-01

Crizotinib, a tyrosine kinase inhibitor, exhibits some cases of an increase in serum creatinine levels. Creatinine is excreted by not only glomerular filtration but also active secretion by organic cation transporters such as organic cation transporter 2 (OCT2). In the present study, we evaluated in vitro inhibitory effect of crizotinib on OCT2 by directly measuring creatinine uptake by OCT2. Coincubation of crizotinib reduced uptake of [ 14 C]creatinine by cultured HEK293 cells expressing OCT2 (HEK293/OCT2) in a concentration-dependent manner with IC 50 values of 1.58 ± 0.24 μM. Preincubation or both preincubation and coincubation (preincubation/coincubation) with crizotinib showed stronger inhibitory effect on [ 14 C]creatinine uptake compared with that in coincubation alone with IC 50 values of 0.499 ± 0.076 and 0.347 ± 0.040 μM, respectively. These IC 50 values of crizotinib on [ 3 H]N-methyl-4-phenylpyridinium acetate uptake by OCT2 were 10-20 times higher than those of [ 14 C]creatinine uptake. Furthermore, preincubation of crizotinib inhibited creatinine uptake by OCT2 in an apparently competitive manner. In conclusion, crizotinib at a clinically relevant concentration has the potential to inhibit creatinine transport by OCT2, suggesting an increase of serum creatinine levels in clinical use. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Population activity structure of excitatory and inhibitory neurons.

Science.gov (United States)

Bittner, Sean R; Williamson, Ryan C; Snyder, Adam C; Litwin-Kumar, Ashok; Doiron, Brent; Chase, Steven M; Smith, Matthew A; Yu, Byron M

2017-01-01

Many studies use population analysis approaches, such as dimensionality reduction, to characterize the activity of large groups of neurons. To date, these methods have treated each neuron equally, without taking into account whether neurons are excitatory or inhibitory. We studied population activity structure as a function of neuron type by applying factor analysis to spontaneous activity from spiking networks with balanced excitation and inhibition. Throughout the study, we characterized population activity structure by measuring its dimensionality and the percentage of overall activity variance that is shared among neurons. First, by sampling only excitatory or only inhibitory neurons, we found that the activity structures of these two populations in balanced networks are measurably different. We also found that the population activity structure is dependent on the ratio of excitatory to inhibitory neurons sampled. Finally we classified neurons from extracellular recordings in the primary visual cortex of anesthetized macaques as putative excitatory or inhibitory using waveform classification, and found similarities with the neuron type-specific population activity structure of a balanced network with excitatory clustering. These results imply that knowledge of neuron type is important, and allows for stronger statistical tests, when interpreting population activity structure.

Population activity structure of excitatory and inhibitory neurons.

Directory of Open Access Journals (Sweden)

Sean R Bittner

Full Text Available Many studies use population analysis approaches, such as dimensionality reduction, to characterize the activity of large groups of neurons. To date, these methods have treated each neuron equally, without taking into account whether neurons are excitatory or inhibitory. We studied population activity structure as a function of neuron type by applying factor analysis to spontaneous activity from spiking networks with balanced excitation and inhibition. Throughout the study, we characterized population activity structure by measuring its dimensionality and the percentage of overall activity variance that is shared among neurons. First, by sampling only excitatory or only inhibitory neurons, we found that the activity structures of these two populations in balanced networks are measurably different. We also found that the population activity structure is dependent on the ratio of excitatory to inhibitory neurons sampled. Finally we classified neurons from extracellular recordings in the primary visual cortex of anesthetized macaques as putative excitatory or inhibitory using waveform classification, and found similarities with the neuron type-specific population activity structure of a balanced network with excitatory clustering. These results imply that knowledge of neuron type is important, and allows for stronger statistical tests, when interpreting population activity structure.

Population activity structure of excitatory and inhibitory neurons

Science.gov (United States)

Doiron, Brent

2017-01-01

Many studies use population analysis approaches, such as dimensionality reduction, to characterize the activity of large groups of neurons. To date, these methods have treated each neuron equally, without taking into account whether neurons are excitatory or inhibitory. We studied population activity structure as a function of neuron type by applying factor analysis to spontaneous activity from spiking networks with balanced excitation and inhibition. Throughout the study, we characterized population activity structure by measuring its dimensionality and the percentage of overall activity variance that is shared among neurons. First, by sampling only excitatory or only inhibitory neurons, we found that the activity structures of these two populations in balanced networks are measurably different. We also found that the population activity structure is dependent on the ratio of excitatory to inhibitory neurons sampled. Finally we classified neurons from extracellular recordings in the primary visual cortex of anesthetized macaques as putative excitatory or inhibitory using waveform classification, and found similarities with the neuron type-specific population activity structure of a balanced network with excitatory clustering. These results imply that knowledge of neuron type is important, and allows for stronger statistical tests, when interpreting population activity structure. PMID:28817581

Membrane interaction and secondary structure of de novo designed arginine-and tryptophan peptides with dual function

KAUST Repository

Rydberg, Hanna A.; Carlsson, Nils; Nordé n, Bengt

2012-01-01

of arg/trp peptides and investigated how the position and number of tryptophans affect cellular uptake. Here we explore the antimicrobial properties and the interaction with lipid model membranes of these peptides, using minimal inhibitory concentrations

Nonlinear concentration gradients regulated by the width of channels for observation of half maximal inhibitory concentration (IC50) of transporter proteins.

Science.gov (United States)

Abe, Yuta; Kamiya, Koki; Osaki, Toshihisa; Sasaki, Hirotaka; Kawano, Ryuji; Miki, Norihisa; Takeuchi, Shoji

2015-08-21

This paper describes a simple microfluidic device that can generate nonlinear concentration gradients. We changed the "width" of channels that can drastically shorten the total microfluidic channel length and simplify the microfluidic network design rather than the "length" of channels. The logarithmic concentration gradients generated by the device were in good agreement with those obtained by simulation. Using this device, we evaluated a probable IC50 value of the ABC transporter proteins by the competitive transport assays at five different logarithmic concentrations. This probable IC50 value was in good agreement with an IC50 value (0.92 μM) obtained at the diluted concentrations of seven points.

Emergent spatial patterns of excitatory and inhibitory synaptic strengths drive somatotopic representational discontinuities and their plasticity in a computational model of primary sensory cortical area 3b

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Kamil A. Grajski

2016-07-01

Full Text Available Mechanisms underlying the emergence and plasticity of representational discontinuities in the mammalian primary somatosensory cortical representation of the hand are investigated in a computational model. The model consists of an input lattice organized as a three-digit hand forward-connected to a lattice of cortical columns each of which contains a paired excitatory and inhibitory cell. Excitatory and inhibitory synaptic plasticity of feedforward and lateral connection weights is implemented as a simple covariance rule and competitive normalization. Receptive field properties are computed independently for excitatory and inhibitory cells and compared within and across columns. Within digit representational zones intracolumnar excitatory and inhibitory receptive field extents are concentric, single-digit, small, and unimodal. Exclusively in representational boundary-adjacent zones, intracolumnar excitatory and inhibitory receptive field properties diverge: excitatory cell receptive fields are single-digit, small, and unimodal; and the paired inhibitory cell receptive fields are bimodal, double-digit, and large. In simulated syndactyly (webbed fingers, boundary-adjacent intracolumnar receptive field properties reorganize to within-representation type; divergent properties are reacquired following syndactyly release. This study generates testable hypotheses for assessment of cortical laminar-dependent receptive field properties and plasticity within and between cortical representational zones. For computational studies, present results suggest that concurrent excitatory and inhibitory plasticity may underlie novel emergent properties.

Characterization of Melanogenesis Inhibitory Constituents of Morus alba Leaves and Optimization of Extraction Conditions Using Response Surface Methodology.

Science.gov (United States)

Jeong, Ji Yeon; Liu, Qing; Kim, Seon Beom; Jo, Yang Hee; Mo, Eun Jin; Yang, Hyo Hee; Song, Dae Hye; Hwang, Bang Yeon; Lee, Mi Kyeong

2015-05-14

Melanin is a natural pigment that plays an important role in the protection of skin, however, hyperpigmentation cause by excessive levels of melatonin is associated with several problems. Therefore, melanogenesis inhibitory natural products have been developed by the cosmetic industry as skin medications. The leaves of Morus alba (Moraceae) have been reported to inhibit melanogenesis, therefore, characterization of the melanogenesis inhibitory constituents of M. alba leaves was attempted in this study. Twenty compounds including eight benzofurans, 10 flavonoids, one stilbenoid and one chalcone were isolated from M. alba leaves and these phenolic constituents were shown to significantly inhibit tyrosinase activity and melanin content in B6F10 melanoma cells. To maximize the melanogenesis inhibitory activity and active phenolic contents, optimized M. alba leave extraction conditions were predicted using response surface methodology as a methanol concentration of 85.2%; an extraction temperature of 53.2 °C and an extraction time of 2 h. The tyrosinase inhibition and total phenolic content under optimal conditions were found to be 74.8% inhibition and 24.8 μg GAE/mg extract, which were well-matched with the predicted values of 75.0% inhibition and 23.8 μg GAE/mg extract. These results shall provide useful information about melanogenesis inhibitory constituents and optimized extracts from M. alba leaves as cosmetic therapeutics to reduce skin hyperpigmentation.

Characterization of Melanogenesis Inhibitory Constituents of Morus alba Leaves and Optimization of Extraction Conditions Using Response Surface Methodology

Directory of Open Access Journals (Sweden)

Ji Yeon Jeong

2015-05-01

Full Text Available Melanin is a natural pigment that plays an important role in the protection of skin, however, hyperpigmentation cause by excessive levels of melatonin is associated with several problems. Therefore, melanogenesis inhibitory natural products have been developed by the cosmetic industry as skin medications. The leaves of Morus alba (Moraceae have been reported to inhibit melanogenesis, therefore, characterization of the melanogenesis inhibitory constituents of M. alba leaves was attempted in this study. Twenty compounds including eight benzofurans, 10 flavonoids, one stilbenoid and one chalcone were isolated from M. alba leaves and these phenolic constituents were shown to significantly inhibit tyrosinase activity and melanin content in B6F10 melanoma cells. To maximize the melanogenesis inhibitory activity and active phenolic contents, optimized M. alba leave extraction conditions were predicted using response surface methodology as a methanol concentration of 85.2%; an extraction temperature of 53.2 °C and an extraction time of 2 h. The tyrosinase inhibition and total phenolic content under optimal conditions were found to be 74.8% inhibition and 24.8 μg GAE/mg extract, which were well-matched with the predicted values of 75.0% inhibition and 23.8 μg GAE/mg extract. These results shall provide useful information about melanogenesis inhibitory constituents and optimized extracts from M. alba leaves as cosmetic therapeutics to reduce skin hyperpigmentation.

Antibacterial activity of anthraquinone from cassia seed on spiced pig head

Science.gov (United States)

Xu, L. Y.; Li, X.; Cui, Y. Q.; Pang, M. X.; Wang, F.; Qi, J. H.

2018-01-01

[Objective] To optimize the extraction of anthraquinone from cassia seed by ultrasonic extraction and its antibacterial activity. [Method] The influences of different extraction time and ethanol concentration, on anthraquinone content were evaluated by a single factor experiment. And anthraquinone content was determined by ultraviolet spectrophotometry. The bacteriostasis of anthraquinone on spiced pig head’s common putrefying bacteria: Staphylococcus, Serratieae, Bacillus, Proteus and the minimal inhibitory concentration (MIC) were studied by oxford plate assay system. [Result] The best extraction time was 30 minutes and the best ethanol concentration was 80%. The antibacterial activity of the cassia seed anthraquinone on Staphylococcus Aureus, Bacillus Proteus is obviously, the minimum inhibitory concentrations were 0.125 g/mL, 0.125 g/mL, 1 g/mL respectively and no inhibitory effect on Serratieae. [Conclusions] The anthraquinones from Cassia seed can inhibit a part of spoilage bacteria in spiced pig heads.

Intrinsically-generated fluctuating activity in excitatory-inhibitory networks

Science.gov (United States)

Mastrogiuseppe, Francesca; Ostojic, Srdjan

2017-01-01

Recurrent networks of non-linear units display a variety of dynamical regimes depending on the structure of their synaptic connectivity. A particularly remarkable phenomenon is the appearance of strongly fluctuating, chaotic activity in networks of deterministic, but randomly connected rate units. How this type of intrinsically generated fluctuations appears in more realistic networks of spiking neurons has been a long standing question. To ease the comparison between rate and spiking networks, recent works investigated the dynamical regimes of randomly-connected rate networks with segregated excitatory and inhibitory populations, and firing rates constrained to be positive. These works derived general dynamical mean field (DMF) equations describing the fluctuating dynamics, but solved these equations only in the case of purely inhibitory networks. Using a simplified excitatory-inhibitory architecture in which DMF equations are more easily tractable, here we show that the presence of excitation qualitatively modifies the fluctuating activity compared to purely inhibitory networks. In presence of excitation, intrinsically generated fluctuations induce a strong increase in mean firing rates, a phenomenon that is much weaker in purely inhibitory networks. Excitation moreover induces two different fluctuating regimes: for moderate overall coupling, recurrent inhibition is sufficient to stabilize fluctuations; for strong coupling, firing rates are stabilized solely by the upper bound imposed on activity, even if inhibition is stronger than excitation. These results extend to more general network architectures, and to rate networks receiving noisy inputs mimicking spiking activity. Finally, we show that signatures of the second dynamical regime appear in networks of integrate-and-fire neurons. PMID:28437436

Sub-inhibitory cefsulodin sensitization of E. coli to β-lactams is mediated by PBP1b inhibition.

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Sujoy K Sarkar

Full Text Available The combination of antibiotics is one of the strategies to combat drug-resistant bacteria, though only a handful of such combinations are in use, such as the β-lactam combinations. In the present study, the efficacy of a specific sub-inhibitory concentration of cefsulodin with other β-lactams was evaluated against a range of Gram-negative clinical isolates. This approach increased the sensitivity of the isolates, regardless of the β-lactamase production. The preferred target and mechanism of action of cefsulodin were identified in laboratory strains of Escherichia coli, by examining the effects of deleting the penicillin-binding protein (PBP 1a and 1b encoding genes individually. Deletion of PBP1b was involved in sensitizing the bacteria to β-lactam agents, irrespective of its O-antigen status. Moreover, the use of a sub-inhibitory concentration of cefsulodin in combination with a β-lactam exerted an effect similar to that one obtained for PBP1b gene deletion. We conclude that the identified β-lactam/cefsulodin combination works by inhibiting PBP1b (at least partially despite the involvement of β-lactamases, and therefore could be extended to a broad range of Gram-negative pathogens.

Potential anti-cholinesterase and β-site amyloid precursor protein cleaving enzyme 1 inhibitory activities of cornuside and gallotannins from Cornus officinalis fruits.

Science.gov (United States)

Bhakta, Himanshu Kumar; Park, Chan Hum; Yokozawa, Takako; Tanaka, Takashi; Jung, Hyun Ah; Choi, Jae Sue

2017-07-01

Cholinesterase (ChE) and β-site amyloid precursor protein cleaving enzyme 1 (BACE1) inhibitors are promising agents for the treatment of Alzheimer's disease (AD). In the present study, we examined the inhibitory activity of seven compounds isolated from the fruits of Cornus officinalis, cornuside, polymeric proanthocyanidins, 1,2,3-tri-O-galloyl-β-D-glucose, 1,2,3,6-tetra-O-galloyl-β-D-glucose, tellimagrandin I, tellimagrandin II, and isoterchebin, against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and BACE1. All of the compounds displayed concentration-dependent in vitro inhibitory activity toward the ChEs and BACE1. Among them, tellimagrandin II exhibited the best inhibitory activity toward ChEs, whereas the best BACE1 inhibitor was 1,2,3,6-tetra-O-galloyl-β-D-glucose. Isoterchebin and polymeric proanthocyanidins were also significant ChE inhibitors. The kinetic and docking studies demonstrated that all compounds interacted with both the catalytic active sites and the peripheral anionic sites of the ChEs and BACE1. Tellimagrandin II, isoterchebin, and the polymeric proanthocyanidins exhibited concentration-dependent inhibition of peroxynitrite-mediated protein tyrosine nitration. In conclusion, we identified significant ChE and BACE1 inhibitors from Corni Fructus that could have value as new multi-targeted compounds for anti-AD agents.

The enhanced inhibitory effect of different antitumor agents in self-microemulsifying drug delivery systems on human cervical cancer HeLa cells.

Science.gov (United States)

Ujhelyi, Zoltán; Kalantari, Azin; Vecsernyés, Miklós; Róka, Eszter; Fenyvesi, Ferenc; Póka, Róbert; Kozma, Bence; Bácskay, Ildikó

2015-07-21

The aim of this study was to develop topical self-microemulsifying drug delivery systems (SMEDDS) containing antitumor agents (bleomycin, cisplatin and ifosfamide) and to investigate their inhibitory potential in SMEDDS on human cervical cancer HeLa cells. The physicochemical properties of cytostatic drug loaded SMEDDS were characterized. The cytotoxicity of main components of SMEDDS was also investigated. Their IC50 values were determined. HeLa cells were treated by different concentrations of cisplatin, bleomycin and ifosfamide alone and in various SMEDDS. The inhibitory effect on cell growth was analyzed by MTT cell viability assay. Inflammation is a driving force that accelerates cancer development. The inhibitory effect of these antitumor agents has also been tested on HeLa cells in the presence of inflammatory mediators (IL-1-β, TNF-α) as an in vitro model of inflamed human cervix. Significant differences in the cytotoxicity of cytostatic drugs alone and in SMEDDS have been found in a concentration-dependent manner. The self-micro emulsifying system may potentiate the effectiveness of bleomycin, cisplatin and ifosfamide topically. The effect of SMEDDS containing antitumor agents was decreased significantly in the presence of inflammatory mediators. According to our experiments, the optimal SMEDDS formulation is 1:1:2:6:2 ratios of Isopropyl myristate, Capryol 90, Kolliphor RH 40, Cremophor RH40, Transcutol HP and Labrasol. It can be concluded that SMEDDS may increase the inhibitory effect of bleomycin, ifosfamide and cisplatin on human cervical cancer HeLa cells. Inflammation on HeLa cells hinders the effectiveness of SMEDDS containing antitumor agents. Our results might ensure useful data for development of optimal antitumor formulations.

Time Course of Brain Network Reconfiguration Supporting Inhibitory Control.

Science.gov (United States)

Popov, Tzvetan; Westner, Britta U; Silton, Rebecca L; Sass, Sarah M; Spielberg, Jeffrey M; Rockstroh, Brigitte; Heller, Wendy; Miller, Gregory A

2018-05-02

Hemodynamic research has recently clarified key nodes and links in brain networks implementing inhibitory control. Although fMRI methods are optimized for identifying the structure of brain networks, the relatively slow temporal course of fMRI limits the ability to characterize network operation. The latter is crucial for developing a mechanistic understanding of how brain networks shift dynamically to support inhibitory control. To address this critical gap, we applied spectrally resolved Granger causality (GC) and random forest machine learning tools to human EEG data in two large samples of adults (test sample n = 96, replication sample n = 237, total N = 333, both sexes) who performed a color-word Stroop task. Time-frequency analysis confirmed that recruitment of inhibitory control accompanied by slower behavioral responses was related to changes in theta and alpha/beta power. GC analyses revealed directionally asymmetric exchanges within frontal and between frontal and parietal brain areas: top-down influence of superior frontal gyrus (SFG) over both dorsal ACC (dACC) and inferior frontal gyrus (IFG), dACC control over middle frontal gyrus (MFG), and frontal-parietal exchanges (IFG, precuneus, MFG). Predictive analytics confirmed a combination of behavioral and brain-derived variables as the best set of predictors of inhibitory control demands, with SFG theta bearing higher classification importance than dACC theta and posterior beta tracking the onset of behavioral response. The present results provide mechanistic insight into the biological implementation of a psychological phenomenon: inhibitory control is implemented by dynamic routing processes during which the target response is upregulated via theta-mediated effective connectivity within key PFC nodes and via beta-mediated motor preparation. SIGNIFICANCE STATEMENT Hemodynamic neuroimaging research has recently clarified regional structures in brain networks supporting inhibitory control. However, due to

Design of 3-D Printed Concentric Tube Robots

OpenAIRE

Morimoto, Tania K.; Okamura, Allison M.

2016-01-01

Concentric tube surgical robots are minimally invasive devices with the advantages of snake-like reconfigurability, long and thin form factor, and placement of actuation outside the patient’s body. These robots can also be designed and manufactured to acquire targets in specific patients for treating specific diseases in a manner that minimizes invasiveness. We propose that concentric tube robots can be manufactured using 3-D printing technology on a patient- and procedure-specific basis. In ...

Evaluation of the Impact of Varied Carvacrol Concentrations on Salmonella Recovery in Oregano and How Corn Oil Can Minimize the Effect of Carvacrol during Preenrichment.

Science.gov (United States)

Beaubrun, Junia Jean-Gilles; Addy, Nicole; Keltner, Zachary; Farris, Samantha; Ewing, Laura; Gopinath, Gopal; Hanes, Darcy E

2018-06-01

Phenolic compounds, like carvacrol, in oregano interfere with the detection of foodborne pathogens such as Salmonella enterica. Carvacrol concentration varies based on plant cultivars and growth region. Six oregano cultivars were used to compare the impact of carvacrol concentration on Salmonella and to evaluate the effectiveness of corn oil to help increase Salmonella survival for detection. The results of Agilent 1200 series high-performance liquid chromatography analysis showed that carvacrol concentration in the six oregano cultivars ranged from 64 to 11,200 ppm. Oregano samples were artificially contaminated with S. enterica and were preenriched in Trypticase soy broth with or without 2% (v/v) corn oil. After 18 to 24 h at 37°C, aliquots were transferred to selective enrichment broths. Salmonella was recovered onto xylose lysine Tergitol 4 agar. Six Salmonella serovars were compared, and recovery varied based on carvacrol concentration and serovar. Samples with higher concentrations of carvacrol showed Salmonella recovery only when they were preenriched with corn oil. Based on metagenomic analysis, the microflora associated with the oregano also varied per cultivar. The results show that, as carvacrol levels increased, Salmonella survival decreased. However, the addition of corn oil to the preenrichment broth can minimize the antimicrobial effects of the phenolic compounds, thus allowing for increased detection of Salmonella from oregano cultivars.

[Study on the inhibitory activity, in vitro, of baicalein and baicalin against skin fungi and bacteria].

Science.gov (United States)

Yang, D; Hu, H; Huang, S; Chaumont, J P; Millet, J

2000-05-01

In this paper, we concentrated in examining, in vitro, the antiseptic activity of the baicalein and baicalin upon the seventeen pathogenic skin fungal and sixteen skin bacterial strains, these two flavonic compounds were known principally as the biosubstances of a traditional Chinese medicinal plant: Scutellaria baicalensis. In agar media, the baicalein possessed potent specific activity against the pathogenic yeasts with MICs of 70-100 micrograms/ml; But in the same condition, no inhibitory effect was observed upon dermatophytes and filamentous imperfect fungi for baicalein, and upon all used strains for baicalin. According to the antibacterial test of baicalein, a high efficacy was achieved against certain causative specie of axillary and foot's odour such as Micrococcus sedentarius, Staphylococcus epidermidis, S. hominis and C. xerosis with a MICs inferior to 250 micrograms/ml. The good inhibitory activity of baicalein could be linked to the group hydroxyl (-OH) in position seven of the molecule.

Hypotensive and Angiotensin-Converting Enzyme Inhibitory Activities of Eisenia fetida Extract in Spontaneously Hypertensive Rats

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Shumei Mao

2015-01-01

Full Text Available Objectives. This study aimed to investigate the antihypertensive effects of an Eisenia fetida extract (EFE and its possible mechanisms in spontaneously hypertensive rats (SHR rats. Methods. Sixteen-week-old SHR rats and Wistar-Kyoto rats (WKY rats were used in this study. Rats were, respectively, given EFE (EFE group, captopril (captopril group, or phosphate-buffered saline (PBS (normal control group and SHR group for 4 weeks. ACE inhibitory activity of EFE in vitro was determined. The systolic blood pressure (SBP and diastolic blood pressure (DBP were measured using a Rat Tail-Cuff Blood Pressure System. Levels of angiotensin II (Ang II, aldosterone (Ald, and 6-keto-prostaglandin F1 alpha (6-keto-PGF1α in plasma were determined by radioimmunoassay, and serum nitric oxide (NO concentration was measured by Griess reagent systems. Results. EFE had marked ACE inhibitory activity in vitro (IC50 = 2.5 mg/mL. After the 4-week drug management, SHR rats in EFE group and in captopril group had lower SBP and DBP, lower levels of Ang II and Ald, and higher levels of 6-keto-PGF1α and NO than the SHR rats in SHR group. Conclusion. These results indicate that EFE has hypotensive effects in SHR rats and its effects might be associated with its ACE inhibitory activity.

Water-Soluble Polysaccharide Extracts from the Oyster Culinary-Medicinal Mushroom Pleurotus ostreatus (Agaricomycetes) with HMGCR Inhibitory Activity.

Science.gov (United States)

Gil-Ramirez, Alicia; Smiderle, Fhernanda R; Morales, Diego; Govers, Coen; Synytsya, Andriy; Wichers, Harry J; Iacomini, Marcello; Soler-Rivas, Cristina

2017-01-01

Water extracts from Pleurotus ostreatus containing no statins showed 3-hydroxy-3-methyl-glutaryl CoA reductase (HMGCR) inhibitory activity (in vitro) that might be due to specific water-soluble polysaccharides (WSPs); when isolated and deproteinized, increasing concentrations of the WSP extract induced higher inhibition. The WSP extract contained mainly β-glucans, mannogalactans, and glycogen (e.g., α-glucans), although derivatives or fragments with lower molecular weights (between 14 and 3.5 kDa) were present and were able to induce the inhibitory activity. The extract contained more β-(1→3)-glucans than β-(11→3),(11→6)-glucans, and they partially survived digestion and managed to pass through Caco2 cell monolayers to the lower compartment after in vitro digestion and transport experiments. The WSP might also modulate Caco2 membrane integrity.

Inhibitory Effect of Nisin on Listeria monocytogenes Inoculated into Surimi and Minced Meat

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Masoud Rezaei

2012-02-01

Full Text Available Background & Objective: Listeria monocytogenes has already established as an important food born pathogen which induce listeriosis in human. Use of bacteriocins to provide food safety has been increased dramatically. Nisin has a wide spectrum inhibitory effect than the other bacteriocins and inhibits food-borne pathogens such as L. monocytogenes and many other Gram-positive spoilage microorganisms. The purpose of this study was to investigate the inhibitory effect of Nisin on population of Listeria monocytogenes and the role of changes in food components on the antilisterial properties of Nisin. Materials & Methods: The minced meat and surimi samples were inoculated by 1×104 cfu/g of L. monocytogenes. Then samples exposed to Nisin at the levels of 500 or 1000 IU/g were prepared. All treatments after packaging in plastic bags were kept for 12 days at refrigerator temperature. Samples were cultured on CHROMagarTM Listeria every 2 days and the number of listeria monocytogenes was counted. Results: two different concentrations of Nisin (500 or 1000 IU/g was not able to inhibit L. monocytogenes below the acceptable level for raw food (100 cells per g in minced meat and surimi of silver carp. But the number of bacteria reduces more in fish surimi as compared to the mince meal. Also, antilisterial activity of Nisin was reduced during the storage period. Conclusion: Inhibitory property of Nisin against L. monocytogenes in surimi significantly was higher than the minced (P<0.05. So it is possible the antilisterial properties of Nisin will increase by elimination of some enzymes during processing.

Expression and function of macrophage migration inhibitory factor (MIF in melioidosis.

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W Joost Wiersinga

2010-02-01

Full Text Available Macrophage migration inhibitory factor (MIF has emerged as a pivotal mediator of innate immunity and has been shown to be an important effector molecule in severe sepsis. Melioidosis, caused by Burkholderia pseudomallei, is an important cause of community-acquired sepsis in Southeast-Asia. We aimed to characterize the expression and function of MIF in melioidosis.MIF expression was determined in leukocytes and plasma from 34 melioidosis patients and 32 controls, and in mice infected with B. pseudomallei. MIF function was investigated in experimental murine melioidosis using anti-MIF antibodies and recombinant MIF. Patients demonstrated markedly increased MIF mRNA leukocyte and MIF plasma concentrations. Elevated MIF concentrations were associated with mortality. Mice inoculated intranasally with B. pseudomallei displayed a robust increase in pulmonary and systemic MIF expression. Anti-MIF treated mice showed lower bacterial loads in their lungs upon infection with a low inoculum. Conversely, mice treated with recombinant MIF displayed a modestly impaired clearance of B. pseudomallei. MIF exerted no direct effects on bacterial outgrowth or phagocytosis of B. pseudomallei.MIF concentrations are markedly elevated during clinical melioidosis and correlate with patients' outcomes. In experimental melioidosis MIF impaired antibacterial defense.

Antioxidant, Iron Chelating and Tyrosinase Inhibitory Activities of Extracts from Talinum triangulare Leach Stem

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Ana Paula Oliveira Amorim

2013-07-01

Full Text Available The aim of this work is to evaluate the antioxidant activity against the radical species DPPH, the reducing capacity against Fe II ions, and the inhibitory activity on the tyrosinase enzyme of the T. triangulare. Hydromethanolic crude extract provided two fractions after the liquid/liquid partition with chloroform. The Folin-Ciocalteu method determined the total phenolic content of the crude extract (CE and the hydromethanolic fraction (Fraction 1, resulting in a concentration of 0.5853 g/100 g for Fraction 1, and 0.1400 g/100 g for the CE. Taking into account the results of the DPPH, the free radical scavenging capacity was confirmed. The formation of complexes with Fe II ions was evaluated by UV/visible spectrometry; results showed that CE has complexing power similar to the positive control (Gingko biloba extract.The inhibitory capacity of samples against the tyrosinase enzyme was determined by the oxidation of L-DOPA, providing IC50 values of 13.3 μg·mL−1 (CE and 6.6 μg·mL−1 (Fraction 1. The values indicate that Fraction 1 was more active and showed a higher inhibitory power on the tyrosinase enzyme than the ascorbic acid, used as positive control. The hydromethanolic extract of T. triangulare proved to have powerful antioxidant activity and to inhibit the tyrosinase enzyme; its potential is increased after the partition with chloroform.

Determination of minimum inhibitory concentrations of itraconazole, terbinafine and ketoconazole against dermatophyte species by broth microdilution method

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V K Bhatia

2015-01-01

Full Text Available Purpose: Various antifungal agents both topical and systemic have been introduced into clinical practice for effectively treating dermatophytic conditions. Dermatophytosis is the infection of keratinised tissues caused by fungal species of genera Trichophyton, Epidermophyton and Microsporum, commonly known as dermatophytes affecting 20–25% of the world's population. The present study aims at determining the susceptibility patterns of dermatophyte species recovered from superficial mycoses of human patients in Himachal Pradesh to antifungal agents; itraconazole, terbinafine and ketoconazole. The study also aims at determining the minimum inhibitory concentrations (MICs of these agents following the recommended protocol of Clinical and Laboratory Standards Institute (CLSI (M38-A2. Methodology: A total of 53 isolates of dermatophytes (T. mentagrophyte-34 in no., T. rubrum-18 and M. gypseum-1 recovered from the superficial mycoses were examined. Broth microdilution method M38-A2 approved protocol of CLSI (2008 for filamentous fungi was followed for determining the susceptibility of dermatophyte species. Results: T. mentagrophyte isolates were found more susceptible to both itraconazole and ketoconazole as compared to terbinafine (MIC50: 0.125 µg/ml for itraconazole, 0.0625 µg/ml for ketoconazole and 0.5 µg/ml for terbinafine. Three isolates of T. mentagrophytes (VBS-5, VBSo-3 and VBSo-73 and one isolate of T. rubrum (VBPo-9 had higher MIC values of itraconazole (1 µg/ml. Similarly, the higher MIC values of ketoconazole were observed in case of only three isolates of T. mentagrophyte (VBSo-30 = 2 µg/ml; VBSo-44, VBM-2 = 1 µg/ml. The comparative analysis of the three antifungal drugs based on t-test revealed that 'itraconazole and terbinafine' and 'terbinafine and ketoconazole' were found independent based on the P < 0.005 in case of T. mentagrophyte isolates. In case of T. rubrum, the similarity existed between MIC values of 'itraconazole and

Comparative phytochemical and growth inhibitory studies on the leaf ...

African Journals Online (AJOL)

Comparative phytochemical and growth inhibitory studies on the leaf and root bark extracts of securinega Virosa (roxb ex. Willd) baill ... The growth inhibitory tests were carried out between 1-30 mg/ in a period of 24-96 h while the phytochemical screening was carried out on the plant parts using standard methods. At 24 h ...

Inhibitory control in childhood stuttering

NARCIS (Netherlands)

Eggers, K.; de Nil, L.; Van den Bergh, B.R.H.

2013-01-01

Purpose The purpose of this study was to investigate whether previously reported parental questionnaire-based differences in inhibitory control (IC; Eggers, De Nil, & Van den Bergh, 2010) would be supported by direct measurement of IC using a computer task. Method Participants were 30 children who

Optimization of Nutrient Composition for Producing ACE Inhibitory Peptides from Goat Milk Fermented by Lactobacillus bulgaricus LB6.

Science.gov (United States)

Shu, Guowei; Shi, Xiaoyu; Chen, He; Ji, Zhe; Meng, Jiangpeng

2018-03-23

Hypertension is a serious threat to human health and food-derived angiotensin converting enzyme (ACE; EC 3.4.15.1) inhibitory peptides can be used to regulate high blood pressure without side effects. The composition of the nutrient medium for the production of these peptides by fermenting goat milk with Lactobacillus bulgaricus LB6 was optimized to increase the ACE inhibitory activity by Box-Behnken design (BBD) of response surface methodology (RSM) in the present study. Soybean peptone, glucose, and casein had significant effects on both ACE inhibition rate and viable counts of L. bulgaricus LB6 during incubation. The results showed that the maximum values of ACE inhibition rate and viable counts for L. bulgaricus LB6 were reaching to 86.37 ± 0.53% and 8.06 × 10 7 under the optimal conditions, which were 0.35% (w/w) soybean peptone, 1.2% (w/w) glucose, and 0.15% (w/w) casein. The results were in close agreement with the model prediction. The optimal values of the medium component concentrations can be a good reference for obtaining ACE inhibitory peptides from goat milk.

Phlorotannin Extracts from Fucales Characterized by HPLC-DAD-ESI-MSn: Approaches to Hyaluronidase Inhibitory Capacity and Antioxidant Properties

Science.gov (United States)

Ferreres, Federico; Lopes, Graciliana; Gil-Izquierdo, Angel; Andrade, Paula B.; Sousa, Carla; Mouga, Teresa; Valentão, Patrícia

2012-01-01

Purified phlorotannin extracts from four brown seaweeds (Cystoseira nodicaulis (Withering) M. Roberts, Cystoseira tamariscifolia (Hudson) Papenfuss, Cystoseira usneoides (Linnaeus) M. Roberts and Fucus spiralis Linnaeus), were characterized by HPLC-DAD-ESI-MSn. Fucophloroethol, fucodiphloroethol, fucotriphloroethol, 7-phloroeckol, phlorofucofuroeckol and bieckol/dieckol were identified. The antioxidant activity and the hyaluronidase (HAase) inhibitory capacity exhibited by the extracts were also assessed. A correlation between the extracts activity and their chemical composition was established. F. spiralis, the species presenting higher molecular weight phlorotannins, generally displayed the strongest lipid peroxidation inhibitory activity (IC50 = 2.32 mg/mL dry weight) and the strongest HAase inhibitory capacity (IC50 = 0.73 mg/mL dry weight). As for superoxide radical scavenging, C. nodicaulis was the most efficient species (IC50 = 0.93 mg/mL dry weight), followed by F. spiralis (IC50 = 1.30 mg/mL dry weight). These results show that purified phlorotannin extracts have potent capabilities for preventing and slowing down the skin aging process, which is mainly associated with free radical damage and with the reduction of hyaluronic acid concentration, characteristic of the process. PMID:23222802

Optimization of inhibitory decision rules relative to length and coverage

KAUST Repository

Alsolami, Fawaz; Chikalov, Igor; Moshkov, Mikhail; Zielosko, Beata

2012-01-01

The paper is devoted to the study of algorithms for optimization of inhibitory rules relative to the length and coverage. In contrast with usual rules that have on the right-hand side a relation "attribute ≠ value", inhibitory rules have a relation

A radioimmunoassay of gastric inhibitory polypeptide in human plasma

International Nuclear Information System (INIS)

Sarson, D.L.; Bryant, M.G.; Bloom, S.R.

1980-01-01

A sensitive radioimmunoassay for the measurement of human gastric inhibitory polypeptide (GIP), using pure porcine GIP, has been developed. Cross-reactivity of the antiserum with all available mammalian gut peptide preparations was negligible with the exception of glucagon when it was approximately 1%. Two major molecular forms of GIP were detectable in plasma and tissue extracts, one of large molecular size and the other corresponding to the elution coefficient of pure porcine standard. Concentrations of GIP in plasma from 50 normal subjects after overnight fasting were 9+-1.0(S.E.M.) pmol/1 rising to a peak of 34+-2.8 pmol/1 following the ingestion of a small mixed test meal. Ingestion of glucose or fat resulted in a similar rise of plasma GIP, whereas no change was observed after the ingestion of protein. (author)

Analysis of glycation induced protein cross-linking inhibitory effects of some antidiabetic plants and spices.

Science.gov (United States)

Perera, Handunge Kumudu Irani; Handuwalage, Charith Sandaruwan

2015-06-09

Protein cross-linking which occurs towards the latter part of protein glycation is implicated in the development of chronic diabetic complications. Glycation induced protein cross-linking inhibitory effects of nine antidiabetic plants and three spices were evaluated in this study using a novel, simple, electrophoresis based method. Methanol extracts of thirteen plants including nine antidiabetic plants and three spices were used. Lysozyme and fructose were incubated at 37 °C in the presence or absence of different concentrations of plant extracts up to 31 days. Standard glycation inhibitor aminoguanidine and other appropriate controls were included. A recently established sodium dodecyl polyacrylamide gel electrophoresis (SDS-PAGE) method was used to detect the products of protein cross-linking in the incubation mixtures. High molecular weight protein products representing the dimer, trimer and tetramer of lysozyme were detected in the presence of fructose. Among the nine antidiabetic plants, seven showed glycation induced protein cross-linking inhibitory effects namely Ficus racemosa (FR) stem bark, Gymnema sylvestre (GS) leaves, Musa paradisiaca (MP) yam, Phyllanthus debilis (PD) whole plant, Phyllanthus emblica (PE) fruit, Pterocarpus marsupium (PM) latex and Tinospora cordifolia (TC) leaves. Inhibition observed with Coccinia grandis (CG) leaves and Strychnos potatorum (SP) seeds were much low. Leaves of Gymnema lactiferum (GL), the plant without known antidiabetic effects showed the lowest inhibition. All three spices namely Coriandrum sativum (CS) seeds, Cinnamomum zeylanicum (CZ) bark and Syzygium aromaticum (SA) flower buds showed cross-link inhibitory effects with higher effects in CS and SA. PD, PE, PM, CS and SA showed almost complete inhibition on the formation of cross-linking with 25 μg/ml extracts. Methanol extracts of PD, PE, PM, CS and SA have shown promising inhibitory effects on glycation induced protein cross-linking.

INHIBITORY EFFECT OF SALVIA SCLAREA

African Journals Online (AJOL)

rakoe

2011-11-02

Nov 2, 2011 ... This study demonstrated anti-herpes simplex virus (HSV) activity of lavender, sage and ... Green monkey kidney cells were protected from HSV-2 infection by ... The highest inhibitory effect against HSV-2 was observed after treatment ..... some nuclear-replicating eukaryotic DNA viruses with large genomes.

Inhibitory effect of farnesol on biofilm formation by Candida tropicalis

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E Zibafar

2009-03-01

Full Text Available ABSTRACT Background: Candidiasis associated with indwelling medical devices is especially problematic since they can act as substrates for biofilm growth which are highly resistant to antifungal drugs. Farnesol is a quorum-sensing molecule that inhibits filamentation and biofilm formation in Candida albicans. Since in recent years Candida tropicalis have been reported as an important and common non-albicans Candida species with high drug resistance pattern, the inhibitory effect of farnesol on biofilm formation by Candida tropicalis was evaluated. Methods: Five Candida tropicalis strains were treated with different concentration of farnesol (0, 30 and 300 µM after 0, 1 and 4 hrs of adherence and then they were maintained under biofilm formation condition in polystyrene, 96-well microtiter plates at 37°C for 48 hrs. Biofilm formation was measured by a semiquantitative colorimetric technique based on reduction assay of 2,3- bis  -2H-tetrazolium- 5- carboxanilide (XTT. Results: The results indicated that the initial adherence time had no effect on biofilm formation and low concentration of farnesol (30 µM could not inhibit biofilm formation. However the presence of non-adherent cells increased biofilm formation significantly and the high concentration of farnesol (300 µM could inhibit biofilm formation. Conclusion: Results of this study showed that the high concentration of farnesol could inhibit biofilm formation and may be used as an adjuvant in prevention and in therapeutic strategies with antifungal drugs.

Angiotensin-converting enzyme-inhibitory activity in protein hydrolysates from normal and anthracnose disease-damaged Phaseolus vulgaris seeds.

Science.gov (United States)

Hernández-Álvarez, Alan Javier; Carrasco-Castilla, Janet; Dávila-Ortiz, Gloria; Alaiz, Manuel; Girón-Calle, Julio; Vioque-Peña, Javier; Jacinto-Hernández, Carmen; Jiménez-Martínez, Cristian

2013-03-15

Bean seeds are an inexpensive source of protein. Anthracnose disease caused by the fungus Colletotrichum lindemuthianum results in serious losses in common bean (Phaseolus vulgaris L.) crops worldwide, affecting any above-ground plant part, and protein dysfunction, inducing the synthesis of proteins that allow plants to improve their stress tolerance. The aim of this study was to evaluate the use of beans damaged by anthracnose disease as a source of peptides with angiotensin-converting enzyme (ACE-I)-inhibitory activity. Protein concentrates from beans spoiled by anthracnose disease and from regular beans as controls were prepared by alkaline extraction and precipitation at isolelectric pH and hydrolysed using Alcalase 2.4 L. The hydrolysates from spoiled beans had ACE-I-inhibitory activity (IC(50) 0.0191 mg protein mL(-1)) and were very similar to those from control beans in terms of ACE-I inhibition, peptide electrophoretic profile and kinetics of hydrolysis. Thus preparation of hydrolysates using beans affected by anthracnose disease would allow for revalorisation of this otherwise wasted product. The present results suggest the use of spoiled bean seeds, e.g. anthracnose-damaged beans, as an alternative for the isolation of ACE-I-inhibitory peptides to be further introduced as active ingredients in functional foods. © 2012 Society of Chemical Industry.

COMPARATIVE EVALUATION OF INHIBITORY ACTIVITY OF ...

African Journals Online (AJOL)

Osondu

2013-02-26

Feb 26, 2013 ... especially the four bacteria isolates used in this study are present in the epiphgram of both normal and ... Keyword: Albino snail, Archachatina marginata, Inhibitory activity, Epiphgram, Bacteria isolate. Introduction .... evolution.

Detection of the pyrogen in the radiopharmaceuticals using Limulus test and inhibitory factors in the gelation reaction

Energy Technology Data Exchange (ETDEWEB)

Murata, H; Iio, M; Yamada, H; Chiba, K [Tokyo Metropolitan Geriatric Medical Center (Japan); Kobayashi, M

1975-08-01

To examine the sensitivities of the Limulus test and the inhibitory factors in radiopharmaceuticals, the following procedures were employed. Twenty commonly used radiopharmaceuticals were examined by Limulus Lysate (Pre-gel). In order to detect the inhibitory factors, several doses of endotoxin (E. coli) were added to the radiopharmaceuticals before the Limulus test was made and the results were compared with control results using saline solution of endotoxin. When the pH of the reaction solution lay out of a suitable range (6.0-7.5), the pH was adjusted by Tris-HCl buffer before the reaction. The sensitivity of the Limulus test control using Pre-gel was positive at a concentration of 10/sup -3/ ..mu..g/ml of endotoxin. The Limulus test was sensitive and without inhibitory reactions for sup(99m)TcO/sub 4/-, sup(99m)Tc-albumin, sup(99m)Tc-MAA, sup(99m)Tc-Sn-colloid, /sup 131/I-hippurate, Na/sup 131/I, Na/sub 2//sup 51/CrO/sub 4/, /sup 67/Ga-citrate and /sup 57/Co-bleomycin as they were supplied. /sup 111/In-DTPA, sup(99m)Tc-phytate, sup(99m)Tc-pyrophosphate, sup(99m)Tc-DTPA, /sup 131/I-PVP, /sup 59/FeCl/sub 3/, Na-phosphate (/sup 32/P), /sup 198/Au-colloid and /sup 75/Se-selenomethionine needed to have their pH adjusted to avoid inhibition. Benzyl alcohol in the radiopharmaceutical showed an inhibitory effect at a concentration greater than 1%. Commonly used /sup 169/Yb-DTPA which was evaluated by this test had a sensitivity of 2.5 x 10/sup -3/ ..mu..g/ml due to addition of a small amount of benzyl alcohol. /sup 131/I-BSP showed intense inhibition in gelation reaction. Contaminations of endotoxin were detected in sup(99m)Tc-albumin, sup(99m)Tc-Sn-colloid, /sup 131/I-hippurate, Na/sup 131/I, Na/sub 2//sup 51/CrO/sub 4/, /sup 198/Au-colloid, /sup 57/Co-bleomycin and /sup 75/Se-selenomethionine.

Inhibitory Effect of Gamma-Irradiated Chitosan on the Growth of Denitrifiers

Directory of Open Access Journals (Sweden)

Javier Vilcáez

2009-01-01

Full Text Available In order to find an environmentally benign substitute to hazardous inhibitory agents, the inhibitory effect of -irradiated chitosans against a mixed culture of denitrifying bacteria was experimentally evaluated. Unlike other studies using pure aerobic cultures, the observed effect was not a complete inhibition but a transient inhibition reflected by prolonged lag phases and reduced growth rates. Raw chitosan under acid conditions (pH 6.3 exerted the strongest inhibition followed by the 100 kGy and 500 kGy irradiated chitosans, respectively. Therefore, because the molecular weight of chitosan decreases with the degree of -irradiation, the inhibitory properties of chitosan due to its high molecular weight were more relevant than the inhibitory properties gained due to the modification of the surface charge and/or chemical structure by -irradiation. High dosage of -irradiated appeared to increase the growth of mixed denitrifying bacteria in acid pH media. However, in neutral pH media, high dosage of -irradiation appeared to enhance the inhibitory effect of chitosan.

Inhibitory effects on anaerobic digestion of swine manure

Energy Technology Data Exchange (ETDEWEB)

Cheung, P.W.S.; Zhou, H. [Univ. of Guelph, School of Engineering, Guelph, Ontario (Canada)]. E-mail: hzhou@uoguelph.ca; Hacker, R. [Univ. of Guelph, Dept. of Animal and Poultry Science, Guelph, Ontario (Canada)

2002-06-15

This paper presents a laboratory study using anaerobic digestion for swine manure under both mesophilic and thermophilic conditions, with emphasis on the effects of inhibitory chemicals on biogas production. A series of batch tests were conducted to examine the effects of various process parameters by varying temperature, pH, ammonia and hydrogen sulfide concentrations. As well, continuous anaerobic digestion tests were conducted using a completely stirred reactor system with a sludge retention time of 15 days. The results showed that at the initial stage, biogas was generated rapidly in the thermophilic reactor, but was more and more inhibited during the later stage with the presence of ammonia and hydrogen sulfide. In contrast, the biogas production was initially delayed in the mesophilic reactor but afterwards had an even higher total gas production. In order to take advantages of both temperature effects in each reactor, the dual-stage system that consists of a thermophilic reactor followed by a mesophilic reactor was suggested. (author)

Inhibitory effects on anaerobic digestion of swine manure

International Nuclear Information System (INIS)

Cheung, P.W.S.; Zhou, H.; Hacker, R.

2002-01-01

This paper presents a laboratory study using anaerobic digestion for swine manure under both mesophilic and thermophilic conditions, with emphasis on the effects of inhibitory chemicals on biogas production. A series of batch tests were conducted to examine the effects of various process parameters by varying temperature, pH, ammonia and hydrogen sulfide concentrations. As well, continuous anaerobic digestion tests were conducted using a completely stirred reactor system with a sludge retention time of 15 days. The results showed that at the initial stage, biogas was generated rapidly in the thermophilic reactor, but was more and more inhibited during the later stage with the presence of ammonia and hydrogen sulfide. In contrast, the biogas production was initially delayed in the mesophilic reactor but afterwards had an even higher total gas production. In order to take advantages of both temperature effects in each reactor, the dual-stage system that consists of a thermophilic reactor followed by a mesophilic reactor was suggested. (author)

Inhibitory Control Mediates the Association between Perceived Stress and Secure Relationship Quality

Directory of Open Access Journals (Sweden)

Toria Herd

2018-02-01

Full Text Available Past research has demonstrated negative associations between exposure to stressors and quality of interpersonal relationships among children and adolescents. Nevertheless, underlying mechanisms of this association remain unclear. Chronic stress has been shown to disrupt prefrontal functioning in the brain, including inhibitory control abilities, and evidence is accumulating that inhibitory control may play an important role in secure interpersonal relationship quality, including peer problems and social competence. In this prospective longitudinal study, we examine whether changes in inhibitory control, measured at both behavioral and neural levels, mediate the association between stress and changes in secure relationship quality with parents and peers. The sample included 167 adolescents (53% males who were first recruited at age 13 or 14 years and assessed annually three times. Adolescents’ inhibitory control was measured by their behavioral performance and brain activities, and adolescents self-reported perceived stress levels and relationship quality with mothers, fathers, and peers. Results suggest that behavioral inhibitory control mediates the association between perceived stress and adolescent’s secure relationship quality with their mothers and fathers, but not their peers. In contrast, given that stress was not significantly correlated with neural inhibitory control, we did not further test the mediation path. Our results highlight the role of inhibitory control as a process through which stressful life experiences are related to impaired secure relationship quality between adolescents and their mothers and fathers.

Inhibitory Control Mediates the Association between Perceived Stress and Secure Relationship Quality.

Science.gov (United States)

Herd, Toria; Li, Mengjiao; Maciejewski, Dominique; Lee, Jacob; Deater-Deckard, Kirby; King-Casas, Brooks; Kim-Spoon, Jungmeen

2018-01-01

Past research has demonstrated negative associations between exposure to stressors and quality of interpersonal relationships among children and adolescents. Nevertheless, underlying mechanisms of this association remain unclear. Chronic stress has been shown to disrupt prefrontal functioning in the brain, including inhibitory control abilities, and evidence is accumulating that inhibitory control may play an important role in secure interpersonal relationship quality, including peer problems and social competence. In this prospective longitudinal study, we examine whether changes in inhibitory control, measured at both behavioral and neural levels, mediate the association between stress and changes in secure relationship quality with parents and peers. The sample included 167 adolescents (53% males) who were first recruited at age 13 or 14 years and assessed annually three times. Adolescents' inhibitory control was measured by their behavioral performance and brain activities, and adolescents self-reported perceived stress levels and relationship quality with mothers, fathers, and peers. Results suggest that behavioral inhibitory control mediates the association between perceived stress and adolescent's secure relationship quality with their mothers and fathers, but not their peers. In contrast, given that stress was not significantly correlated with neural inhibitory control, we did not further test the mediation path. Our results highlight the role of inhibitory control as a process through which stressful life experiences are related to impaired secure relationship quality between adolescents and their mothers and fathers.

Inhibitory effect of tocotrienol on eukaryotic DNA polymerase λ and angiogenesis

International Nuclear Information System (INIS)

Mizushina, Yoshiyuki; Nakagawa, Kiyotaka; Shibata, Akira; Awata, Yasutoshi; Kuriyama, Isoko; Shimazaki, Noriko; Koiwai, Osamu; Uchiyama, Yukinobu; Sakaguchi, Kengo; Miyazawa, Teruo; Yoshida, Hiromi

2006-01-01

Tocotrienols, vitamin E compounds that have an unsaturated side chain with three double bonds, selectively inhibited the activity of mammalian DNA polymerase λ (pol λ) in vitro. These compounds did not influence the activities of replicative pols such as α, δ, and ε, or even the activity of pol β which is thought to have a very similar three-dimensional structure to the pol β-like region of pol λ. Since δ-tocotrienol had the strongest inhibitory effect among the four (α- to δ-) tocotrienols, the isomer's structure might be an important factor in the inhibition of pol λ. The inhibitory effect of δ-tocotrienol on both intact pol λ (residues 1-575) and a truncated pol λ lacking the N-terminal BRCA1 C-terminus (BRCT) domain (residues 133-575, del-1 pol λ) was dose-dependent, with 50% inhibition observed at a concentration of 18.4 and 90.1 μM, respectively. However, del-2 pol λ (residues 245-575) containing the C-terminal pol β-like region was unaffected. Tocotrienols also inhibited the proliferation of and formation of tubes by bovine aortic endothelial cells, with δ-tocotrienol having the greatest effect. These results indicated that tocotrienols targeted both pol λ and angiogenesis as anti-cancer agents. The relationship between the inhibition of pol λ and anti-angiogenesis by δ-tocotrienol was discussed

Histamine release inhibitory activity of Piper nigrum leaf.

Science.gov (United States)

Hirata, Noriko; Naruto, Shunsuke; Inaba, Kazunori; Itoh, Kimihisa; Tokunaga, Masashi; Iinuma, Munekazu; Matsuda, Hideaki

2008-10-01

Oral administration of a methanolic extract of Piper nigrum leaf (PN-ext, 50, 200 and 500 mg/kg) showed a potent dose-dependent inhibition of dinitrofluorobenzene (DNFB)-induced cutaneous reaction at 1 h [immediate phase response (IPR)] after and 24 h [late phase response (LPR)] after DNFB challenge in mice which were passively sensitized with anti-dinitrophenyl (DNP) IgE antibody. Ear swelling inhibitory effect of PN-ext (50, 200 and 500 mg/kg, per os (p.o.)) on very late phase response (vLPR) in the model mice was significant but weaker than that on IPR. Oral administration of PN-ext (50, 200 and 500 mg/kg for 7 d) inhibited picryl chloride (PC)-induced ear swelling in PC sensitized mice. PN-ext exhibited in vitro inhibitory effect on compound 48/80-induced histamine release from rat peritoneal mast cells. Two lignans of PN-ext, (-)-cubebin (1) and (-)-3,4-dimethoxy-3,4-desmethylenedioxycubebin (2), were identified as major active principles having histamine release inhibitory activity.

The inhibitory effect of Penicillium camemberti and Geotruchum candidum on the associated funga of white mould cheese

DEFF Research Database (Denmark)

Decker, Marianne; Nielsen, P.V.

2005-01-01

effects of C. herbarum, and this was most pronounced in the early stages of growth. The interaction mechanism of C. herbarum was not affected by the choice of the strain of P. camemberti whereas the Penicillium contaminants were very sensitive to the choice of the R. camemberti strain. The presence of G...... contamination at the critical point of the salt brine. Pure P. camemberti had the largest inhibitory effect on the C. herbarum contaminant. Adding G. candidum in mixed cultures weakened the inhibitory effect of P. camemberti on C. herbarum. Low levels of G. candidum (10(3) spore/ml) promoted visible growth....... candidum in the mixed cultures seems to decrease the suppressing effect of pour-plated P. camemberti. No correlation of any kind was found in the pour-plated spore concentration totals by the inhibition of the C. herbarum and P. roqueforti contaminants whereas R. caseifulvum and P commune were sensitive...

Evidence for inhibitory nicotinic and facilitatory muscarinic receptors in cholinergic nerve terminals of the rat urinary bladder.

Science.gov (United States)

Somogyi, G T; de Groat, W C

1992-02-01

Cholinergic prejunctional modulatory receptors on parasympathetic nerves in the rat urinary bladder were studied by measuring 3H-acetylcholine (ACh) release in muscle strips from the bladder body. Electrical field stimulation markedly increased 3H-ACh overflow in strips preloaded with 3H-choline. Oxotremorine (1 microM), an M2 receptor agonist and DMPP (10 microM) a nicotinic (N) receptor agonist decreased the release of ACh (50% and 55% respectively); whereas McN-A 343 (50 microM) an M1 receptor agonist increased the release (33%), indicating the presence of three types of modulatory receptors. The anticholinesterase agent, physostigmine in concentrations of 1, 5 and 25 microM and neostigmine (5 microM) increased ACh release (44-710%). However a low concentration of physostigmine (0.05 microM) decreased release. Pirenzepine, an M1 muscarinic antagonist or atropine blocked the increased ACh release in physostigmine-treated strips, but in normal strips pirenzepine did not change release and atropine increased release. McN-A 343 or prolonged application (15 min) of DMPP increased ACh release (376% and 391% respectively) in physostigmine-treated strips. The response to McN-A 343 was blocked by pirenzepine. d-Tubocurarine (DTC), a nicotinic receptor blocker, enhanced ACh release in the presence of physostigmine but proved to be ineffective in normal preparations. These findings suggest that all three cholinergic receptors (M1 facilitatory, N inhibitory and M2 inhibitory) are activated by endogenous ACh in physostigmine treated preparations whereas only M2-inhibitory receptors are activated in normal preparations. It will be important in future studies to determine whether M1 and M2 mechanisms can also be activated under more physiological conditions in the bladder and whether they are present at other cholinergic synapses.

Cholecystokinin receptor-1 mediates the inhibitory effects of exogenous cholecystokinin octapeptide on cellular morphine dependence

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Wen Di

2012-06-01

Full Text Available Abstract Background Cholecystokinin octapeptide (CCK-8, the most potent endogenous anti-opioid peptide, has been shown to regulate the processes of morphine dependence. In our previous study, we found that exogenous CCK-8 attenuated naloxone induced withdrawal symptoms. To investigate the precise effect of exogenous CCK-8 and the role of cholecystokinin (CCK 1 and/or 2 receptors in morphine dependence, a SH-SY5Y cell model was employed, in which the μ-opioid receptor, CCK1/2 receptors, and endogenous CCK are co-expressed. Results Forty-eight hours after treating SH-SY5Y cells with morphine (10 μM, naloxone (10 μM induced a cAMP overshoot, indicating that cellular morphine dependence had been induced. The CCK receptor and endogenous CCK were up-regulated after chronic morphine exposure. The CCK2 receptor antagonist (LY-288,513 at 1–10 μM inhibited the naloxone-precipitated cAMP overshoot, but the CCK1 receptor antagonist (L-364,718 did not. Interestingly, CCK-8 (0.1-1 μM, a strong CCK receptor agonist, dose-dependently inhibited the naloxone-precipitated cAMP overshoot in SH-SY5Y cells when co-pretreated with morphine. The L-364,718 significantly blocked the inhibitory effect of exogenous CCK-8 on the cAMP overshoot at 1–10 μM, while the LY-288,513 did not. Therefore, the CCK2 receptor appears to be necessary for low concentrations of endogenous CCK to potentiate morphine dependence in SH-SY5Y cells. An additional inhibitory effect of CCK-8 at higher concentrations appears to involve the CCK1 receptor. Conclusions This study reveals the difference between exogenous CCK-8 and endogenous CCK effects on the development of morphine dependence, and provides the first evidence for the participation of the CCK1 receptor in the inhibitory effects of exogenous CCK-8 on morphine dependence.

Minimally processed vegetable salads: microbial quality evaluation.

Science.gov (United States)

Fröder, Hans; Martins, Cecília Geraldes; De Souza, Katia Leani Oliveira; Landgraf, Mariza; Franco, Bernadette D G M; Destro, Maria Teresa

2007-05-01

The increasing demand for fresh fruits and vegetables and for convenience foods is causing an expansion of the market share for minimally processed vegetables. Among the more common pathogenic microorganisms that can be transmitted to humans by these products are Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella. The aim of this study was to evaluate the microbial quality of a selection of minimally processed vegetables. A total of 181 samples of minimally processed leafy salads were collected from retailers in the city of Sao Paulo, Brazil. Counts of total coliforms, fecal coliforms, Enterobacteriaceae, psychrotrophic microorganisms, and Salmonella were conducted for 133 samples. L. monocytogenes was assessed in 181 samples using the BAX System and by plating the enrichment broth onto Palcam and Oxford agars. Suspected Listeria colonies were submitted to classical biochemical tests. Populations of psychrotrophic microorganisms >10(6) CFU/g were found in 51% of the 133 samples, and Enterobacteriaceae populations between 10(5) and 106 CFU/g were found in 42% of the samples. Fecal coliform concentrations higher than 10(2) CFU/g (Brazilian standard) were found in 97 (73%) of the samples, and Salmonella was detected in 4 (3%) of the samples. Two of the Salmonella-positive samples had minimally processed vegetables had poor microbiological quality, and these products could be a vehicle for pathogens such as Salmonella and L. monocytogenes.

Performa Inhibitory Control dengan Induksi Sing-a-Song Stress Test pada Dewasa Awal

Directory of Open Access Journals (Sweden)

Akhmad Kurniawan

2018-04-01

Full Text Available Inhibitory control is able to control attention by inhibiting internal tendencies and external influences. Inhibitory control is controlled by dorsolateral prefrontal cortex and anterior cingulate cortex, that can be affected by stress variable. Sing-a-Song Stress Test (SSST is a current method to induce stress that has never been practiced in study of inhibitory control. This study aimed to determine the effect of SSST against inhibitory control in early adult. Between subjects design was applied in this study. A number of 35 participants with age range from 17 to 21 years old were randomly assigned into experimental group (n = 17 and control group (n = 18. Inhibitory control was measured using Computerized Stroop Color-Word Test (CSCWT. Positive Affect and Negative Affect Schedule (PANAS was used to conduct a manipulation check. Independent-Samples T Test explained no significant effect of stress on inhibitory control (t = -0,117; p > 0,05.

( Asteraceae ) methanol extracts against Helicobacter pylori

African Journals Online (AJOL)

Methanol vehicle did not affect H. pylori growth. Conclusion: The observed antibacterial effect of G. glutinosum extracts may be of benefit as an adjuvant treatment of diseases caused by H. pylori. Key words: Gymnosperma glutinosum, Helicobacter pylori, methanol extract, minimal inhibitory concentration (MIC).

Generation and Characterization of Inhibitory Antibodies Specific to Guinea Pig CXCR1 and CXCR2.

Science.gov (United States)

Tanaka, Kento; Yoshimura, Chigusa; Shiina, Tetsuo; Terauchi, Tomoko; Yoshitomi, Tomomi; Hirahara, Kazuki

2017-04-01

CXCR1 and CXCR2 are chemokine receptors that have different selectivity of chemokine ligands, but the distinct role of each receptor is not clearly understood. This is due to the absence of specific inhibitors in guinea pigs, which are the appropriate species for investigation of CXCR1 and CXCR2 because of their functional similarity to humans. In this study, we generated and evaluated monoclonal antibodies that specifically bound to guinea pig CXCR1 (gpCXCR1) and guinea pig CXCR2 (gpCXCR2) for acquisition of specific inhibitors. To assess the activity of antibodies, we established CHO-K1 cells stably expressing either gpCXCR1 or gpCXCR2 (CHO/gpCXCR1 or CHO/gpCXCR2). CHO/gpCXCR1 showed migration in response to guinea pig interleukin (IL)-8, and CHO/gpCXCR2 showed migration in response to both guinea pig IL-8 and guinea pig growth-regulated oncogene α. The receptor selectivities of the chemokines of guinea pigs were the same as the human orthologs. The inhibitory activities of the anti-gpCXCR1 and anti-gpCXCR2 monoclonal antibodies on cell migration were observed in a concentration-dependent manner. In conclusion, we successfully obtained inhibitory antibodies specific to gpCXCR1 and gpCXCR2. These inhibitory antibodies will be useful to clarify the physiological roles of CXCR1 and CXCR2 in guinea pigs.

Antioxidant and ACE-inhibitory activities of hemp (Cannabis sativa L.) protein hydrolysates produced by the proteases AFP, HT, Pro-G, actinidin and zingibain.

Science.gov (United States)

Teh, Sue-Siang; Bekhit, Alaa El-Din A; Carne, Alan; Birch, John

2016-07-15

Hemp protein isolates (HPIs) were hydrolysed by proteases (AFP, HT, ProG, actinidin and zingibain). The enzymatic hydrolysis of HPIs was evaluated through the degree of hydrolysis and SDS-PAGE profiles. The bioactive properties of the resultant hydrolysates (HPHs) were accessed through ORAC, DPPḢ scavenging and ACE-inhibitory activities. The physical properties of the resultant HPHs were evaluated for their particle sizes, zeta potential and surface hydrophobicity. HT had the highest rate of caseinolytic activity at the lowest concentration (0.1 mg mL(-1)) compared to other proteases that required concentration of 100 mg mL(-1) to achieve their maximum rate of caseinolytic activity. This led to the highest degree of hydrolysis of HPIs by HT in the SDS-PAGE profiles. Among all proteases and substrates, HT resulted in the highest bioactivities (ORAC, DPPḢ scavenging and ACE-inhibitory activities) generated from alkali extracted HPI in the shortest time (2 h) compared to the other protease preparations. Copyright © 2016 Elsevier Ltd. All rights reserved.

Well-constructed cellulose acetate membranes for forward osmosis: Minimized internal concentration polarization with an ultra-thin selective layer

KAUST Repository

Zhang, Sui

2010-09-01

The design and engineering of membrane structure that produces low salt leakage and minimized internal concentration polarization (ICP) in forward osmosis (FO) processes have been explored in this work. The fundamentals of phase inversion of cellulose acetate (CA) regarding the formation of an ultra-thin selective layer at the bottom interface of polymer and casting substrate were investigated by using substrates with different hydrophilicity. An in-depth understanding of membrane structure and pore size distribution has been elucidated with field emission scanning electronic microscopy (FESEM) and positron annihilation spectroscopy (PAS). A double dense-layer structure is formed when glass plate is used as the casting substrate and water as the coagulant. The thickness of the ultra-thin bottom layer resulted from hydrophilic-hydrophilic interaction is identified to be around 95nm, while a fully porous, open-cell structure is formed in the middle support layer due to spinodal decomposition. Consequently, the membrane shows low salt leakage with mitigated ICP in the FO process for seawater desalination. The structural parameter (St) of the membrane is analyzed by modeling water flux using the theory that considers both external concentration polarization (ECP) and ICP, and the St value of the double dense-layer membrane is much smaller than those reported in literatures. Furthermore, the effects of an intermediate immersion into a solvent/water mixed bath prior to complete immersion in water on membrane formation have been studied. The resultant membranes may have a single dense layer with an even lower St value. A comparison of fouling behavior in a simple FO-membrane bioreactor (MBR) system is evaluated for these two types of membranes. The double dense-layer membrane shows a less fouling propensity. This study may help pave the way to improve the membrane design for new-generation FO membranes. © 2010 Elsevier B.V.

Biological Assays and Chemical Composition of Volatile Oils of Bupleurum fruticosum L. (Apiaceae

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Andrea Maxia

2011-01-01

Full Text Available The composition of supercritical CO 2 extracts and essential oils obtained by hydrodistillation of Bupleurum fruticosum L., growing spontaneously in Italy and Portugal, and its antifungal activity is reported. The collected extracts were analyzed by GC-FID and GC-MS methods. The minimal inhibitory concentration (MIC and the minimal lethal concentration (MLC were used to evaluate the antifungal activity of the oils against Candida albicans, C. tropicalis, C. krusei, C. guillermondii, C. parapsilosis, Cryptococcus neoformans, Trichophyton rubrum, T. mentagrophytes, Microsporum canis, M. gypseum, Epidermophyton floccosum, Aspergillus niger, A. fumigatus and A. flavus.

The dipeptidyl peptidase 4 inhibitor vildagliptin does not accentuate glibenclamide-induced hypoglycemia but reduces glucose-induced glucagon-like peptide 1 and gastric inhibitory polypeptide secretion

DEFF Research Database (Denmark)

El-Ouaghlidi, Andrea; Rehring, Erika; Holst, Jens Juul

2007-01-01

BACKGROUND/AIMS: Inhibition of dipeptidyl peptidase 4 by vildagliptin enhances the concentrations of the active form of the incretin hormones glucagon-like peptide 1 (GLP-1) and gastric inhibitory polypeptide (GIP). The present study asked whether vildagliptin accentuates glibenclamide-induced hy...

Preliminary phytochemical screening and alpha-glucosidase inhibitory activity of Philippine taro (Colocasia esculenta (L.) Schott var. PSB-VG #9)

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Lebosada, Richemae Grace R.; Librando, Ivy L.

2017-01-01

The study was conducted to determine the anti-hyperglycemic property in terms of α-glucosidase inhibitory activity of the various parts (corm, leaf and petiole) of Colocasia esculenta (L.) Schott var. PSB-VG #9. Each of the plant parts were extracted with 95% ethanol and concentrated using a rotary evaporator at 40 °C. The crude extracts were screened for the presence of alkaloids, flavonoids, glycosides and saponins using Thin Layer Chromatography. The α-glucosidase inhibitory activity of the crude extracts (50 mg/L) were assayed spectrophotometrically using a microplate reader. The results of the phytochemical screening revealed the presence of alkaloids, flavonoids, and saponins in the leaf part while flavonoids and saponins were detected in the petiole and only saponins were present in the corm. The assay showed that the percentage α-glucosidase inhibition of the 50 mg/L ethanolic crude extract of the corm, leaves and petiole of C. esculenta are 68.03, 71.64 and 71.39%, respectively. Statistical analysis shows significant differences in the α-glucosidase inhibition among the various plant parts. It can be concluded that the ethanolic crude extracts of the different parts of C. esculenta (L.) Schott var. PSB-VG #9 exhibited inhibitory activity against α-glucosidase and the presence of phytochemicals like alkaloids, flavonoids and saponins may have contributed greatly to the inhibitory activity of the plant extract and can be further subjected for isolation of the therapeutically active compounds with antidiabetes potency.

Disruption of Trophic Inhibitory Signaling in Autism Sepctrum Disorders

Science.gov (United States)

2016-12-01

1 AWARD NUMBER: W81XWH-14-1-0433 TITLE: Disruption of Trophic Inhibitory Signaling in Autism Sepctrum Disorders PRINCIPAL INVESTIGATOR: Anis...SUBTITLE 5a. CONTRACT NUMBER Disruption of Trophic Inhibitory Signaling in Autism Sepctrum Disorders 5b. GRANT NUMBER W81XWH-14-1-0433 5c. PROGRAM...chloride co-transporters that control EGABA could be used as a corrective strategy for the synaptic and circuit disruptions demonstrated in the

Inhibitory activities of some vitamins on the formation of cholesterol oxidation products in beef patties.

Science.gov (United States)

Wong, Daniel; Wang, Mingfu

2013-09-04

The capacities of 15 vitamins to inhibit the formation of 7α-hydroxycholesterol, 7β-hydroxycholesterol, and 7-ketocholesterol were examined in beef patties. Their inhibitory activities were tested at a concentration of 0.4 mmol in 30 g of beef. Among them, L-ascorbic acid, retinoic acid, and α-(±)-tocopherol were found to exert a potent inhibitory effect (30-50%) on 7-ketocholesterol formation and (~20%) on 7α-hydroxycholesterol and 7β-hydroxycholesterol formations. Pyridoxamine inhibited 7-ketocholesterol formation by 60% with a statistically significant difference (p cholesterol oxidation, a chemical model with pyridoxamine added in the cholesterol oxidation system (heated at 140 °C for 240 min in dimethyl sulfoxide) was employed. It was demonstrated that pyridoxamine could directly react with 7-ketocholesterol via the addition reaction. The reaction involved a nucleophilic attack of the free amine group of pyridoxamine on 7-ketocholesterol (an α,β-unsaturated carbonyl compound). This type of reaction was also found to occur in beef patties by chromatographic and spectral analyses.

Lactoferricin B-derived peptides with inhibitory effects on ECE-dependent vasoconstriction.

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Fernández-Musoles, Ricardo; López-Díez, José Javier; Torregrosa, Germán; Vallés, Salvador; Alborch, Enrique; Manzanares, Paloma; Salom, Juan B

2010-10-01

Endothelin-converting enzyme (ECE), a key peptidase in the endothelin (ET) system, cleaves inactive big ET-1 to produce active ET-1, which binds to ET(A) receptors to exert its vasoconstrictor and pressor effects. ECE inhibition could be beneficial in the treatment of hypertension. In this study, a set of eight lactoferricin B (LfcinB)-derived peptides, previously characterized in our laboratory as angiotensin-converting enzyme (ACE) inhibitory peptides, was examined for their inhibitory effects on ECE. In vitro inhibitory effects on ECE activity were assessed using both the synthetic fluorogenic peptide substrate V (FPS V) and the natural substrate big ET-1. To study vasoactive effects, an ex vivo functional assay was developed using isolated rabbit carotid artery segments. With FPS V, only four LfcinB-derived peptides induced inhibition of ECE activity, whereas the eight peptides showed ECE inhibitory effects with big ET-1 as substrate. Regarding the ex vivo assays, six LfcinB-derived peptides showed inhibition of big ET-1-induced, ECE-dependent vasoconstriction. A positive correlation between the inhibitory effects of LfcinB-derived peptides on ECE activity when using big ET-1 and the inhibitory effects on ECE-dependent vasoconstriction was shown. ECE-independent vasoconstriction induced by ET-1 was not affected, thus discarding effects of LfcinB-derived peptides on ET(A) receptors or intracellular signal transduction mechanisms. In conclusion, a combined in vitro and ex vivo method to assess the effects of potentially antihypertensive peptides on the ET system has been developed and applied to show the inhibitory effects on ECE-dependent vasoconstriction of six LfcinB-derived peptides, five of which were dual vasopeptidase (ACE/ECE) inhibitors. Copyright © 2010 Elsevier Inc. All rights reserved.

Hydrogel-forming microneedle arrays: Potential for use in minimally-invasive lithium monitoring.

Science.gov (United States)

Eltayib, Eyman; Brady, Aaron J; Caffarel-Salvador, Ester; Gonzalez-Vazquez, Patricia; Zaid Alkilani, Ahlam; McCarthy, Helen O; McElnay, James C; Donnelly, Ryan F

2016-05-01

We describe, for the first time, hydrogel-forming microneedle (s) (MN) arrays for minimally-invasive extraction and quantification of lithium in vitro and in vivo. MN arrays, prepared from aqueous blends of hydrolysed poly(methyl-vinylether-co-maleic anhydride) and crosslinked by poly(ethyleneglycol), imbibed interstitial fluid (ISF) upon skin insertion. Such MN were always removed intact. In vitro, mean detected lithium concentrations showed no significant difference following 30min MN application to excised neonatal porcine skin for lithium citrate concentrations of 0.9 and 2mmol/l. However, after 1h application, the mean lithium concentrations extracted were significantly different, being appropriately concentration-dependent. In vivo, rats were orally dosed with lithium citrate equivalent to 15mg/kg and 30mg/kg lithium carbonate, respectively. MN arrays were applied 1h after dosing and removed 1h later. The two groups, having received different doses, showed no significant difference between lithium concentrations in serum or MN. However, the higher dosed rats demonstrated a lithium concentration extracted from MN arrays equivalent to a mean increase of 22.5% compared to rats which received the lower dose. Hydrogel-forming MN clearly have potential as a minimally-invasive tool for lithium monitoring in outpatient settings. We will now focus on correlation between serum and MN lithium concentrations. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Testosterone 5alpha-reductase inhibitory active constituents of Piper nigrum leaf.

Science.gov (United States)

Hirata, Noriko; Tokunaga, Masashi; Naruto, Shunsuke; Iinuma, Munekazu; Matsuda, Hideaki

2007-12-01

Previously we reported that Piper nigrum leaf extract showed a potent stimulation effect on melanogenesis and that (-)-cubebin (1) and (-)-3,4-dimethoxy-3,4-desmethylenedioxycubebin (2) were isolated as active constituents. As a part of our continuous studies on Piper species for the development of cosmetic hair-care agents, testosterone 5alpha-reductase inhibitory activity of aqueous ethanolic extracts obtained from several different parts of six Piper species, namely Piper nigrum, P. methysticum, P. betle, P. kadsura, P. longum, and P. cubeba, were examined. Among them, the extracts of P. nigrum leaf, P. nigrum fruit and P. cubeba fruit showed potent inhibitory activity. Activity-guided fractionation of P. nigrum leaf extract led to the isolation of 1 and 2. Fruits of P. cubeba contain 1 as a major lignan, thus inhibitory activity of the fruit may be attributable to 1. As a result of further assay on other known constituents of the cited Piper species, it was found that piperine, a major alkaloid amide of P. nigrum fruit, showed potent inhibitory activity, thus a part of the inhibitory activity of P. nigrum fruit may depend on piperine. The 5alpha-reductase inhibitory activities of 1 and piperine were found for the first time. In addition, the P. nigrum leaf extract showed in vivo anti-androgenic activity using the hair regrowth assay in testosterone sensitive male C57Black/6CrSlc strain mice.

α-/β-Glucosidase and α-Amylase Inhibitory Activities of Roselle (Hibiscus sabdariffa L. Ethanol Extract

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Marisca Evalina Gondokesumo

2017-03-01

Full Text Available Background: Diabetes mellitus is a metabolic disease, characterized by hyperglycemia due to disturbance in both insulin secretion and function. One of theurapeutic approaches is to reduce blood glucose levels by inhbiting α-/β-glucosidase and α-amylase involved in carbohydrate digestion. Thus, inhibition of these enzymes play important role in the treatment of diabetes mellitus. Roselle (Hibiscus sabdariffa L. has been known to have several medicinal properties and potency as an antidiabetics agents. This reseacrh aimed to observe antidiabetic properties of roselle ethanol extract (REE towards α-glucosidase, β-glucosidase and α-amylase. Materials and Methods: REE was done with maceration technique using diluent of 70% ethanol. Antidiabetic properties were measured by inhibitory activity of α-amylase, α-glucosidase and β-glucosidase. Results: REE was able to inhibit α-/β-glucosidase and α-amylase in the highest concentration with inhibition percentage of 72.68, 47.34 and 73.08% respectively, and were comparable with Acarbose of 81.49, 50.97, 73.08%. The median inhibitory concentration (IC50 of α-/β-glucosidase and α-amylase of REE were 15.81, 41.77, 18.09 μg/mL respectively, and Acarbose were 9.45, 22.57, 3.64 μg/mL respectively. Conclusions: REE inhibits α-/β-glucosidase and α-amylase. Keywords: Roselle, Acarbose, α-glucosidase, β-glucosidase, α-amylase, antidiabetic

Inhibitory Activity of Avocado Seed Fatty Acid Derivatives (Acetogenins) Against Listeria Monocytogenes.

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Salinas-Salazar, Carmen; Hernández-Brenes, Carmen; Rodríguez-Sánchez, Dariana Graciela; Castillo, Elena Cristina; Navarro-Silva, Jesús Manuel; Pacheco, Adriana

2017-01-01

High standards regarding Listeria monocytogenes control and consumer demands for food products without synthetic additives represent a challenge to food industry. We determined the antilisterial properties of an enriched acetogenin extract (EAE) from avocado seed, compared it to two commercial antimicrobials (one enriched in avocado acetogenins), and tested purified molecules. Acetogenin composition in pulp and seed of Hass avocado was quantified. EAE were obtained by two sequential centrifuge partition chromatography separations and molecules purified by preparative chromatography and quantified by HPLC-MS-TOF and HPLC-PDA. Avocado seed extracts which are the following two: 1) EAE and 2) the commercially available antimicrobial Avosafe®, presented similar inhibition zones and chemical profiles. Minimum inhibitory concentration (MIC) values of extracts and two isolated acetogenins varied between 7.8 and 15.6 mg/L, were effective at 37 and 4 °C, and showed a bactericidal effect probably caused by increased membrane permeability and lytic effects, evidenced by flow cytometry at 10 and 100× MIC. Activity was comparable to Mirenat®. Most potent acetogenins were Persenone C (5) and A (6), and AcO-avocadenyne (1), the latter exclusively present in seed. Common features of bioactive molecules were the acetyl moiety and multiple unsaturations (2 to 3) in the aliphatic chain, some persenones also featured a trans-enone group. Seeds contained 1.6 times higher levels of acetogenins than pulp (5048.1 ± 575.5 and 3107.0 ± 207.2 mg/kg fresh weight, respectively), and total content in pulp was 199 to 398 times higher than MIC values. Therefore, acetogenin levels potentially consumed by humans are higher than inhibitory concentrations. Results document properties of avocado seed acetogenins as natural antilisterial food additives. © 2016 Institute of Food Technologists®.

Identification of the free phenolic profile of Adlay bran by UPLC-QTOF-MS/MS and inhibitory mechanisms of phenolic acids against xanthine oxidase.

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Lin, Lianzhu; Yang, Qingyun; Zhao, Kun; Zhao, Mouming

2018-07-01

Adlay bran free phenolic extract has been previously demonstrated to possess potent xanthine oxidase (XOD) inhibitory activity. The aims of this study were to characterize the free phenolic profile of adlay bran and investigate the structure-activity relationship, underlying mechanism and interaction of phenolic acids as XOD inhibitors. A total of twenty phenolics including ten phenolic acids, two coumarins, two phenolic aldedhyes and six flavonoids were identified in a phenolic compound-guided separation by UPLC-QTOF-MS/MS. Adlay bran free phenolic extract possessed strong XOD inhibitory activity related to hydroxycinnamic acids with methoxyl groups. The hydrogen bonding and hydrophobic interactions were the main forces in the binding of adlay phenolics to XOD. Sinapic acid, identified in adlay bran for the first time, possessed strong XOD inhibitory activity in a mixed non-competitive manner, and synergistic effects with other adlay phenolic acids at low concentrations, and would be a promising agent for preventing and treating hyperuricemia. Copyright © 2018. Published by Elsevier Ltd.

Dogs' reaction to inequity is affected by inhibitory control.

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Brucks, Désirée; Range, Friederike; Marshall-Pescini, Sarah

2017-11-17

Inequity aversion is thought to act as a mechanism to ensure cooperation and has been studied in many different species, consistently revealing inter-individual variation. Inhibitory control has been proposed to act as one factor responsible for this variation since individuals need to inhibit performing the required action and/or refuse rewards in order to exhibit inequity aversion. Here, we investigated if dogs' sensitivity to inequity is affected by their capacity for inhibitory control, assessed in a test battery and questionnaire. Overall, dogs showing high compulsivity scores (i.e. repetitive behaviours independent of feedback) were more motivated to participate in the inequity task independent of the rewarding scheme. Dogs were more sensitive to inequity and individual contrast if they exhibited a slower decision speed in the inhibition tasks. Furthermore, less persistent and more impulsive dogs were more sensitive to reward inequity, potentially due to having a lower tolerance level for frustration. Results indicate that aspects of inhibitory control can explain the variation in dogs' inequity response, highlighting one of the mechanisms underlying responses to inequity. Emphasising the importance to design paradigms, which allow us to disentangle capacities to recognise inequity from the inability to react to it due to poor inhibitory control abilities.

Lactoferricin-related peptides with inhibitory effects on ACE-dependent vasoconstriction.

Science.gov (United States)

Centeno, José M; Burguete, María C; Castelló-Ruiz, María; Enrique, María; Vallés, Salvador; Salom, Juan B; Torregrosa, Germán; Marcos, José F; Alborch, Enrique; Manzanares, Paloma

2006-07-26

A selection of lactoferricin B (LfcinB)-related peptides with an angiotensin I-converting enzyme (ACE) inhibitory effect have been examined using in vitro and ex vivo functional assays. Peptides that were analyzed included a set of sequence-related antimicrobial hexapeptides previously reported and two representative LfcinB-derived peptides. In vitro assays using hippuryl-L-histidyl-L-leucine (HHL) and angiotensin I as substrates allowed us to select two hexapeptides, PACEI32 (Ac-RKWHFW-NH2) and PACEI34 (Ac-RKWLFW-NH2), and also a LfcinB-derived peptide, LfcinB17-31 (Ac-FKCRRWQWRMKKLGA-NH2). Ex vivo functional assays using rabbit carotid arterial segments showed PACEI32 (both D- and L-enantiomers) and LfcinB17-31 have inhibitory effects on ACE-dependent angiotensin I-induced contraction. None of the peptides exhibited in vitro ACE inhibitory activity using bradykinin as the substrate. In conclusion, three bioactive lactoferricin-related peptides exhibit inhibitory effects on both ACE activity and ACE-dependent vasoconstriction with potential to modulate hypertension that deserves further investigation.

Modifying Yeast Tolerance to Inhibitory Conditions of Ethanol Production Processes

DEFF Research Database (Denmark)

Caspeta, Luis; Castillo, Tania; Nielsen, Jens

2015-01-01

Saccharomyces cerevisiae strains having a broad range of substrate utilization, rapid substrate consumption, and conversion to ethanol, as well as good tolerance to inhibitory conditions are ideal for cost-competitive ethanol production from lignocellulose. A major drawback to directly design S....... cerevisiae tolerance to inhibitory conditions of lignocellulosic ethanol production processes is the lack of knowledge about basic aspects of its cellular signaling network in response to stress. Here, we highlight the inhibitory conditions found in ethanol production processes, the targeted cellular...... functions, the key contributions of integrated -omics analysis to reveal cellular stress responses according to these inhibitors, and current status on design-based engineering of tolerant and efficient S. cerevisiae strains for ethanol production from lignocellulose....

Inhibitory effects of rosmarinic acid extracts on porcine pancreatic amylase in vitro.

Science.gov (United States)

McCue, Patrick P; Shetty, Kalidas

2004-01-01

Porcine pancreatic alpha-amylase (PPA) was allowed to react with herbal extracts containing rosmarinic acid (RA) and purified RA. The derivatized enzyme-phytochemical mixtures obtained were characterized for residual amylase activity. These in vitro experiments showed that the amylase activity was inhibited in the presence of these phytochemicals. The extent of amylase inhibition correlated with increased concentration of RA. RA-containing oregano extracts yielded higher than expected amylase inhibition than similar amount of purified RA, suggesting that other phenolic compounds or phenolic synergies may contribute to additional amylase inhibitory activity. The significance of food-grade, plant-based amylase inhibitors for modulation of diabetes mellitus and other oxidation-linked diseases is hypothesized and discussed.

Distinguishing between impairments of working memory and inhibitory control in cases of early dementia.

Science.gov (United States)

Crawford, Trevor J; Higham, Steve

2016-01-29

Dementia (most notably, Alzheimer's Disease) is often associated with impairments of both working memory and inhibitory control. However, it is unclear whether these are functionally distinct impairments. We addressed the issue of whether working memory and inhibitory control can be dissociated, using data from a sample of patients who were recruited in a longitudinal study (Crawford et al., 2013, 2015). The first case revealed a preserved working memory capacity together with poor inhibitory control in the anti-saccade task. A longitudinal follow-up revealed that the defective inhibitory control emerged 12-months before the dementia was evident on the mini-mental state examination assessment. A second case revealed a poor working memory together with a well-preserved level of inhibitory control. The dissociation of working memory and inhibitory control was confirmed statistically in 7 additional cases. These findings yield converging evidence that working memory and inhibitory control are distinct cognitive operations and challenges the Kimberg and Farah (2000) cognitive model of working memory. Copyright © 2015 Elsevier Ltd. All rights reserved.

End-tidal control vs. manually controlled minimal-flow anesthesia: a prospective comparative trial.

Science.gov (United States)

Wetz, A J; Mueller, M M; Walliser, K; Foest, C; Wand, S; Brandes, I F; Waeschle, R M; Bauer, M

2017-11-01

To ensure safe general anesthesia, manually controlled anesthesia requires constant monitoring and numerous manual adjustments of the gas dosage, especially for low- and minimal-flow anesthesia. Oxygen flow-rate and administration of volatile anesthetics can also be controlled automatically by anesthesia machines using the end-tidal control technique, which ensures constant end-tidal concentrations of oxygen and anesthetic gas via feedback and continuous adjustment mechanisms. We investigated the hypothesis that end-tidal control is superior to manually controlled minimal-flow anesthesia (0.5 l/min). In this prospective trial, we included 64 patients undergoing elective surgery under general anesthesia. We analyzed the precision of maintenance of the sevoflurane concentration (1.2-1.4%) and expiratory oxygen (35-40%) and the number of necessary adjustments. Target-concentrations of sevoflurane and oxygen were maintained at more stable levels with the use of end-tidal control (during the first 15 min 28% vs. 51% and from 15 to 60 min 1% vs. 19% deviation from sevoflurane target, P tidal oxygen (5, IQR 3-6). The target-concentrations were reached earlier with the use of end-tidal compared with manual controlled minimal-flow anesthesia but required slightly greater use of anesthetic agents (6.9 vs. 6.0 ml/h). End-tidal control is a superior technique for setting and maintaining oxygen and anesthetic gas concentrations in a stable and rapid manner compared with manual control. Consequently, end-tidal control can effectively support the anesthetist. © 2017 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.

[The inhibitory effect of decomposed Chinese traditional medicine Chaihu on Coxsackie B virus(CVB3m) replication and its influence on cell activity].

Science.gov (United States)

Wang, X; Wang, Y; Liu, F; Wei, K L

2001-09-01

To study the anti-Coxsackie B virus (CVB3m) action of Chaihu(XCT) and its decomposed herb soups No.1 and No.2 in vitro, and also their protective effect on cells. The anti CVB3m and cell protection effects of XCT and its decomposed herb soups No.1 and No.2 were observed by the methods of micro-cell culture and neutral red ingestion, taking cytopathic effect and cell activity as judgments of medicine toxicity and virus replication. The non-toxic concentrations of XCTand its decomposed herb soups No.1 and No.2 had no apparent influence on HeLa cell activity, on the contrary, in certain range of concentrations, they could promote cell growth and cell activity. In therapeutic cell group, XCT and its decomposed herb soups No.1 and No.2 all had apparent inhibitory effect on CVB3m replication, especially the decomposed No.1 showing an inhibitory rate of 107.6%. Under the same decomposed No.1 concentration(1.5 mg/ml), the viral inhibitory rate of the preventive therapeutic cell group was much higher than that of the therapeutic cell group, reaching as high as 128.1%. In virus adsorbed cell group, the CVB3m was also obviously inhibited by the XCT and decomposed No.1 and No.2. By comparing the effects on cell protection and virus replication of XCT and its decomposed herb soups No.1 and No.2, it identifies that XCT can protect cells against virus infection and directly kill the CVB3m, this Chinese herb medicine may be applied clinically for preventing and curing of viral myocarditis.

In vitro activity of difloxacin against canine bacterial isolates

NARCIS (Netherlands)

Hoven, van den J.R.; Wagenaar, J.A.; Walker, R.D.

2000-01-01

The in vitro activity of difloxacin against canine bacterial isolates from clinical cases was studied in the United States and The Netherlands. Minimal inhibitory concentrations (MIC), the postantibiotic effect, the effect of pH on antimicrobial activity, and the bacterial killing rate tests were

Development of a standardized susceptibility test for Campylobacter with quality control ranges for ciprofloxacin, doxycycline, erythromycin, gentamicin, and meropenem

DEFF Research Database (Denmark)

McDermott, P. F.; Bodeis, S. M.; Aarestrup, Frank Møller

2004-01-01

-control (QC) strain. Minimal inhibitory concentration (MIC) QC ranges were determined for two incubation time/temperature combinations: 36degreesC for 48 hr and 42degreesC for 24 hr. Quality-control ranges were determined for ciprofloxacin, doxycycline, erythromycin, gentamicin, and meropenem. For all...

Phytochemical screening and in vitro acetylcholinesterase inhibitory ...

African Journals Online (AJOL)

Phytochemical screening and in vitro acetylcholinesterase inhibitory activity of seven plant extracts. Titilayo Johnson, Oduje A. Akinsanmi, Enoch J. Banbilbwa, Tijani A. Yahaya, Karima Abdulaziz, Kolade Omole ...

The Effect of Domestication on Inhibitory Control: Wolves and Dogs Compared

Science.gov (United States)

Marshall-Pescini, Sarah; Virányi, Zsófia; Range, Friederike

2015-01-01

Inhibitory control i.e. blocking an impulsive or prepotent response in favour of a more appropriate alternative, has been suggested to play an important role in cooperative behaviour. Interestingly, while dogs and wolves show a similar social organization, they differ in their intraspecific cooperation tendencies in that wolves rely more heavily on group coordination in regard to hunting and pup-rearing compared to dogs. Hence, based on the ‘canine cooperation’ hypothesis wolves should show better inhibitory control than dogs. On the other hand, through the domestication process, dogs may have been selected for cooperative tendencies towards humans and/or a less reactive temperament, which may in turn have affected their inhibitory control abilities. Hence, based on the latter hypothesis, we would expect dogs to show a higher performance in tasks requiring inhibitory control. To test the predictive value of these alternative hypotheses, in the current study two tasks; the ‘cylinder task’ and the ‘detour task’, which are designed to assess inhibitory control, were used to evaluate the performance of identically raised pack dogs and wolves. Results from the cylinder task showed a significantly poorer performance in wolves than identically-raised pack dogs (and showed that pack-dogs performed similarly to pet dogs with different training experiences), however contrary results emerged in the detour task, with wolves showing a shorter latency to success and less perseverative behaviour at the fence. Results are discussed in relation to previous studies using these paradigms and in terms of the validity of these two methods in assessing inhibitory control. PMID:25714840

In vitro Investigation of Hydro-alcoholic Extract of Helichrysum leucocephalum on the Inhibition of Streptococcus Mutans Growth

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Motamedifar M

2017-12-01

Full Text Available Statement of Problem: Indiscriminate use of antibacterial agents increases the antibiotic resistance, which consequently necessitates seeking alternatives such as herbal remedies. Objectives: The aim of this study was to evaluate the antimicrobial effect of hydroalcoholic extract of Helichrysum leucocephalum (H.leucocephalum on Streptococcus mutans (S. mutans growth as a major cause of dental caries. Materials and Methods: In this study, hydroalcoholic extract of H. leucocephalum was prepared. The antibacterial effects, minimal inhibitory concentration (MIC, and minimal bactericidal concentration (MBC of hydroalcoholic extract of H. leucocephalum and penicillin were assessed. Agar well diffusion method and micro broth dilution assay were used on bacterial suspension adjusted to a 0.5 McFarland standard (equivalent to 1.5×108 CFU/mL.Each test was repeated four times to minimize lab errors. Results: In this study, the inhibitory zone of hydroalcoholic extract of H.leucocephalum in concentration of 100 mg/mL was 34±0.1 mm and for penicillin was 10 mm. The MIC and MBC of H.leucocephalum hydroalcoholic extract were 5.6±6.25, 21.6±6.25 mg/mL, respectively. Conclusions: Hydroalcoholic extract of H. leucocephalum have antibacterial effect on S.mutans at a concentration of 12.5mg/mL, indicating possible application of this extract in prevention of dental caries; however, future researches are necessary.

Production of Angiotensin-I-Converting-Enzyme-Inhibitory Peptides in Fermented Milks Started by Lactobacillus delbrueckii subsp. bulgaricus SS1 and Lactococcus lactis subsp. cremoris FT4

Science.gov (United States)

Gobbetti, M.; Ferranti, P.; Smacchi, E.; Goffredi, F.; Addeo, F.

2000-01-01

Two fermented milks containing angiotensin-I-converting-enzyme (ACE)-inhibitory peptides were produced by using selected Lactobacillus delbrueckii subsp. bulgaricus SS1 and L. lactis subsp. cremoris FT4. The pH 4.6-soluble nitrogen fraction of the two fermented milks was fractionated by reversed-phase fast-protein liquid chromatography. The fractions which showed the highest ACE-inhibitory indexes were further purified, and the related peptides were sequenced by tandem fast atom bombardment-mass spectrometry. The most inhibitory fractions of the milk fermented by L. delbrueckii subsp. bulgaricus SS1 contained the sequences of β-casein (β-CN) fragment 6-14 (f6-14), f7-14, f73-82, f74-82, and f75-82. Those from the milk fermented by L. lactis subsp. cremoris FT4 contained the sequences of β-CN f7-14, f47-52, and f169-175 and κ-CN f155-160 and f152-160. Most of these sequences had features in common with other ACE-inhibitory peptides reported in the literature. In particular, the β-CN f47-52 sequence had high homology with that of angiotensin-II. Some of these peptides were chemically synthesized. The 50% inhibitory concentrations (IC50s) of the crude purified fractions containing the peptide mixture were very low (8.0 to 11.2 mg/liter). When the synthesized peptides were used individually, the ACE-inhibitory activity was confirmed but the IC50s increased considerably. A strengthened inhibitory effect of the peptide mixtures with respect to the activity of individual peptides was presumed. Once generated, the inhibitory peptides were resistant to further proteolysis either during dairy processing or by trypsin and chymotrypsin. PMID:10966406

Inhibitory control and moral emotions: relations to reparation in early and middle childhood.

Science.gov (United States)

Colasante, Tyler; Zuffianò, Antonio; Bae, Na Young; Malti, Tina

2014-01-01

This study examined links between inhibitory control, moral emotions (sympathy and guilt), and reparative behavior in an ethnically diverse sample of 4- and 8-year-olds (N = 162). Caregivers reported their children's reparative behavior, inhibitory control, and moral emotions through a questionnaire, and children reported their guilt feelings in response to a series of vignettes depicting moral transgressions. A hypothesized meditation model was tested with inhibitory control relating to reparative behavior through sympathy and guilt. In support of this model, results revealed that high levels of inhibitory control were associated with high levels of reparative behavior through high levels of sympathy and guilt. However, the mediation of inhibitory control to reparation through guilt was significant for 4-year-olds only. Results are discussed in relation to the temperamental, regulatory, and affective-moral precursors of reparative behavior in early and middle childhood.

Hunger, inhibitory control and distress-induced emotional eating.

Science.gov (United States)

van Strien, Tatjana; Ouwens, Machteld A; Engel, Carmen; de Weerth, Carolina

2014-08-01

Self-reported emotional eating has been found to significantly moderate distress-induced food intake, with low emotional eaters eating less after a stress task than after a control task and high emotional eaters eating more. The aim of the present study was to explore possible underlying mechanisms by assessing possible associations with (1) ability to experience the typical post-stress reduction of hunger and (2) inhibitory control. We studied these effects in 54 female students who were preselected on the basis of extremely high or low scores on an emotional eating questionnaire. Using a within subject design we measured the difference of actual food or snack intake after a control or a stress task (Trier Social Stress Test). As expected, the moderator effect of emotional eating on distress-induced food intake was found to be only present in females with a failure to report the typical reduction of hunger immediately after a stress task (an a-typical hunger stress response). Contrary to our expectations, this moderator effect of emotional eating was also found to be only present in females with high ability to stop motor impulses (high inhibitory control). These findings suggest that an a-typical hunger stress response but not poor inhibitory control may underlie the moderator effect of emotional eating on distress-induced food intake. However, inhibitory control may play a role whether or not there is a moderator effect of self-reported emotional eating on distress-induced food intake. Copyright © 2014 Elsevier Ltd. All rights reserved.

Self-Averaging Property of Minimal Investment Risk of Mean-Variance Model.

Science.gov (United States)

Shinzato, Takashi

2015-01-01

In portfolio optimization problems, the minimum expected investment risk is not always smaller than the expected minimal investment risk. That is, using a well-known approach from operations research, it is possible to derive a strategy that minimizes the expected investment risk, but this strategy does not always result in the best rate of return on assets. Prior to making investment decisions, it is important to an investor to know the potential minimal investment risk (or the expected minimal investment risk) and to determine the strategy that will maximize the return on assets. We use the self-averaging property to analyze the potential minimal investment risk and the concentrated investment level for the strategy that gives the best rate of return. We compare the results from our method with the results obtained by the operations research approach and with those obtained by a numerical simulation using the optimal portfolio. The results of our method and the numerical simulation are in agreement, but they differ from that of the operations research approach.

Self-Averaging Property of Minimal Investment Risk of Mean-Variance Model.

Directory of Open Access Journals (Sweden)

Takashi Shinzato

Full Text Available In portfolio optimization problems, the minimum expected investment risk is not always smaller than the expected minimal investment risk. That is, using a well-known approach from operations research, it is possible to derive a strategy that minimizes the expected investment risk, but this strategy does not always result in the best rate of return on assets. Prior to making investment decisions, it is important to an investor to know the potential minimal investment risk (or the expected minimal investment risk and to determine the strategy that will maximize the return on assets. We use the self-averaging property to analyze the potential minimal investment risk and the concentrated investment level for the strategy that gives the best rate of return. We compare the results from our method with the results obtained by the operations research approach and with those obtained by a numerical simulation using the optimal portfolio. The results of our method and the numerical simulation are in agreement, but they differ from that of the operations research approach.

Improving oral bioavailability of resveratrol by a UDP-glucuronosyltransferase inhibitory excipient-based self-microemulsion.

Science.gov (United States)

Yang, Fei-Fei; Zhou, Jing; Hu, Xiao; Cong, Zhao-Qing; Liu, Chun-Yu; Pan, Rui-Le; Chang, Qi; Liu, Xin-Min; Liao, Yong-Hong

2018-03-01

Self-microemulsifying (SME) drug delivery system has been developed to increase oral bioavailabilities, and inhibitory excipients are capable of improving oral bioavailability by inhibiting enzyme mediated intestinal metabolism. However, the potential of enzyme inhibitory excipients containing SME in boosting resveratrol bioavailability remains largely uninvestigated. In this study, we set out to prepare SME-1 with UGT inhibitory excipients (excipients without inhibitory activities named SME-2 as control) to increase the bioavailability of RES by inhibiting intestinal metabolism. Results demonstrated that similar physicochemical properties such as size, polydistribution index and in vitro release, cellular uptake and permeability in Caco-2 cells as well as in vivo lymphatic distribution between inhibitory SME-1 and non-inhibitory SME-2 were observed. In vivo study demonstrated that the molar ratios of RES-G/RES were 7.25±0.48 and 5.06±2.42 for free drug and SME-2, respectively, and the molar ratio decreased to 0.36±0.10 in SME-1 group. Pharmacokinetic study confirmed that the inhibitory excipients containing SME demonstrated potential in increasing bioavailability of RES from 6.5% for the free RES and 12.9% for SME-2 to 76.1% in SME-1 through modulating the glucuronidation by UGT inhibitory excipients. Copyright © 2018 Elsevier B.V. All rights reserved.

Optimization of inhibitory decision rules relative to length and coverage

KAUST Repository

Alsolami, Fawaz

2012-01-01

The paper is devoted to the study of algorithms for optimization of inhibitory rules relative to the length and coverage. In contrast with usual rules that have on the right-hand side a relation "attribute ≠ value", inhibitory rules have a relation "attribute = value" on the right-hand side. The considered algorithms are based on extensions of dynamic programming. © 2012 Springer-Verlag.

Inhibitory Synaptic Plasticity - Spike timing dependence and putative network function.

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Tim P Vogels

2013-07-01

Full Text Available While the plasticity of excitatory synaptic connections in the brain has been widely studied, the plasticity of inhibitory connections is much less understood. Here, we present recent experimental and theoretical □ndings concerning the rules of spike timing-dependent inhibitory plasticity and their putative network function. This is a summary of a workshop at the COSYNE conference 2012.

Pharmacokinetic variability of clindamycin and influence of rifampicin on clindamycin concentration in patients with bone and joint infections.

Science.gov (United States)

Curis, Emmanuel; Pestre, Vincent; Jullien, Vincent; Eyrolle, Luc; Archambeau, Denis; Morand, Philippe; Gatin, Laure; Karoubi, Matthieu; Pinar, Nicolas; Dumaine, Valérie; Nguyen Van, Jean-Claude; Babinet, Antoine; Anract, Philippe; Salmon, Dominique

2015-08-01

Clindamycin, a lincosamide antibiotic with a good penetration into bone, is widely used for treating bone and joint infections by Gram-positive pathogens. To be active against Staphylococcus spp, its concentration at the infection site, C, must be higher than 2× the minimal inhibitory concentration (MIC). The aims of the work were to study the determinants of plasma clindamycin trough concentration, C min, especially the effect of co-treatment with rifampicin, and the consequences on clinical outcome. An observational study was performed, involving patients hospitalized for a bone and joint infection who received clindamycin as part of their antibiotic treatment. Target C min was 1.7 mg/L, to reach the desired bone concentration/MIC >2, assuming a 30% diffusion into bone and MIC = 2.5 mg/L. Sixty one patients (mean age: 56.8 years, 57.4% male) were included between 2007 and 2011. 72.1% underwent a surgery on a foreign material, and 91.1% were infected by at least a Gram-positive micro-organism. Median C min value was 1.39 mg/L, with 58% of the values below the threshold value of 1.7 mg/L. Median C min was significantly lower for patients taking rifampicin (0.46 vs 1.52 mg/L, p = 0.034). No patient with rifampicin co-administration reached the target concentration (maximal C min: 0.85 mg/L). After a median follow-up of 17 months (1.5-38 months), 4 patients relapsed, 2 died and 47 (88.7% of the patients with known outcome) were cured, independently of association with rifampicin. This study shows the high inter-variability of plasma clindamycin concentration and confirms that co-treatment with rifampicin significantly decreases clindamycin trough concentrations.

Modifying yeast tolerance to inhibitory conditions of ethanol production processes

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Luis eCaspeta

2015-11-01

Full Text Available Saccharomyces cerevisiae strains having a broad range of substrate utilization, rapid substrate consumption and conversion to ethanol, as well as good tolerance to inhibitory conditions are ideal for cost-competitive ethanol production from lignocellulose. A major drawback to directly design S. cerevisiae tolerance to inhibitory conditions of lignocellulosic ethanol production processes is the lack of knowledge about basic aspects of its cellular signaling network in response to stress. Here we highlight the inhibitory conditions found in ethanol production processes, the targeted cellular functions, the key contributions of integrated –omics analysis to reveal cellular stress responses according to these inhibitors, and current status on design-based engineering of tolerant and efficient S. cerevisiae strains for ethanol production from lignocellulose.

Antibiotics and common antibacterial biocides stimulate horizontal transfer of resistance at low concentrations.

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Jutkina, J; Marathe, N P; Flach, C-F; Larsson, D G J

2018-03-01

There is a rising concern that antibiotics, and possibly other antimicrobial agents, can promote horizontal transfer of antibiotic resistance genes. For most types of antimicrobials their ability to induce conjugation below minimal inhibitory concentrations (MICs) is still unknown. Our aim was therefore to explore the potential of commonly used antibiotics and antibacterial biocides to induce horizontal transfer of antibiotic resistance. Effects of a wide range of sub-MIC concentrations of the antibiotics cefotaxime, ciprofloxacin, gentamicin, erythromycin, sulfamethoxazole, trimethoprim and the antibacterial biocides chlorhexidine digluconate, hexadecyltrimethylammoniumchloride and triclosan were investigated using a previously optimized culture-based assay with a complex bacterial community as a donor of mobile resistance elements and a traceable Escherichia coli strain as a recipient. Chlorhexidine (24.4μg/L), triclosan (0.1mg/L), gentamicin (0.1mg/L) and sulfamethoxazole (1mg/L) significantly increased the frequencies of transfer of antibiotic resistance whereas similar effects were not observed for any other tested antimicrobial compounds. This corresponds to 200 times below the MIC of the recipient for chlorhexidine, 1/20 of the MIC for triclosan, 1/16 of the MIC for sulfamethoxazole and right below the MIC for gentamicin. To our best knowledge, this is the first study showing that triclosan and chlorhexidine could stimulate the horizontal transfer of antibiotic resistance. Together with recent research showing that tetracycline is a potent inducer of conjugation, our results indicate that several antimicrobials including both common antibiotics and antibacterial biocides at low concentrations could contribute to antibiotic resistance development by facilitating the spread of antibiotic resistance between bacteria. Copyright © 2017 Elsevier B.V. All rights reserved.

Short communication: Potential of Fresco-style cheese whey as a source of protein fractions with antioxidant and angiotensin-I-converting enzyme inhibitory activities.

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Tarango-Hernández, S; Alarcón-Rojo, A D; Robles-Sánchez, M; Gutiérrez-Méndez, N; Rodríguez-Figueroa, J C

2015-11-01

Recently, traditional Mexican Fresco-style cheese production has been increasing, and the volume of cheese whey generated represents a problem. In this study, we investigated the chemical composition of Fresco-style cheese wheys and their potential as a source of protein fractions with antioxidant and angiotensin-I-converting enzyme (ACE)-inhibitory activities. Three samples from Fresco, Panela, and Ranchero cheeses whey were physicochemically characterized. Water-soluble extracts were fractionated to obtain whey fractions with different molecular weights: 10-5, 5-3, 3-1 and wheys. All whey fractions had antioxidant and ACE-inhibitory activities. The 10-5 kDa whey fraction of Ranchero cheese had the highest Trolox equivalent antioxidant capacity (0.62 ± 0.00 mM), and the 3-1 kDa Panela and Fresco cheese whey fractions showed the highest ACE-inhibitory activity (0.57 ± 0.02 and 0.59 ± 0.04 μg/mL 50%-inhibitory concentration values, respectively). These results suggest that Fresco-style cheese wheys may be a source of protein fractions with bioactivity, and thus could be useful ingredients in the manufacture of functional foods with increased nutritional value. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Proteolytic and ACE-inhibitory activities of probiotic yogurt containing non-viable bacteria as affected by different levels of fat, inulin and starter culture.

Science.gov (United States)

Shakerian, Mansour; Razavi, Seyed Hadi; Ziai, Seyed Ali; Khodaiyan, Faramarz; Yarmand, Mohammad Saeid; Moayedi, Ali

2015-04-01

In this study, the effects of fat (0.5 %, 3.2 % and 5.0 %), inulin (0.0 and 1.0 %) and starter culture (0.0 %, 0.5 %, 1.0 % and 1.5 %) on the angiotensin converting enzyme (ACE)-inhibitory activity of probiotic yogurt containing non-viable bacteria were assessed. Proteolytic activities of bacteria were also investigated. Yogurts were prepared either using a sole yogurt commercial culture including Streptococcus thermophilus and Lactobacillus delbrueckii subs. bulgaricus or bifidobacterium animalis BB-12 and Lactobacillus acidophilus La5 in addition to yogurt culture. Relative degrees of proteolysis were found to be considerably higher in yogurt samples than UHT milk as the control. Both regular and probiotic yogurts showed considerable ACE-inhibitory activities. Results showed that degree of proteolysis was not influenced by different fat contents, while was increased by high concentration of starter culture (1.5 % w/w) and reduced by inulin (1 % w/w). ACE-inhibitory activities of yogurt were also negatively affected by the presence of inulin and high levels of fat (5 % w/w). Moreover, yogurt containing probiotic bacteria showed higher inhibitory against ACE in comparison to the yogurt prepared with non-probiotic strains.

Predictions for optimal mitigation of paracrine inhibitory signalling in haemopoietic stem cell cultures.

Science.gov (United States)

Berry, Joseph D; Godara, Pankaj; Liovic, Petar; Haylock, David N

2015-04-16

Recent studies in the literature have highlighted the critical role played by cell signalling in determining haemopoietic stem cell (HSC) fate within ex vivo culture systems. Stimulatory signals can enhance proliferation and promote differentiation, whilst inhibitory signals can significantly limit culture output. Numerical models of various mitigation strategies are presented and applied to determine effectiveness of these strategies toward mitigation of paracrine inhibitory signalling inherent in these culture systems. The strategies assessed include mixing, media-exchange, fed-batch and perfusion. The models predict that significant spatial concentration gradients exist in typical cell cultures, with important consequences for subsequent cell expansion. Media exchange is shown to be the most effective mitigation strategy, but remains labour intensive and difficult to scale-up for large culture systems. The fed-batch strategy is only effective at very small Peclet number, and its effect is diminished as the cell culture volume grows. Conversely, mixing is effective at high Peclet number, and ineffective at low Peclet number. The models predict that cell expansion in fed-batch cultures becomes independent of increasing dilution rate, consistent with experimental results previously reported in the literature. In contrast, the models predict that increasing the flow rate in perfused cultures will lead to increased cell expansion, indicating the suitability of perfusion for use as an automated, tunable strategy. The effect of initial cell seeding density is also investigated, with the model showing that perfusion outperforms dilution for all densities considered. The models predict that the impact of inhibitory signalling in HSC cultures can be mitigated against using media manipulation strategies, with the optimal strategy dependent upon the protein diffusion time-scale relative to the media manipulation time-scale. The key messages from this study can be applied to

Inhibitory serum factor of lymphoproliferative response to allogeneic cells in pregnancy

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Silvia Daher

Full Text Available INTRODUCTION: An inhibitory serum factor of mixed lymphocyte culture (MLC has been associated with successful pregnancy after lymphocyte transfusion in women with unexplained recurrent spontaneous abortions (RSA. OBJECTIVE: Investigate whether the inhibitory serum factor of MLC is essential for a successful pregnancy. METHOD: Sera from 33 healthy pregnant women and from 40 women with RSA were assessed by a one-way MLC in which the woman's lymphocytes were stimulated with her partner's lymphocytes or with third party lymphocytes. RESULTS: An inhibitory serum effect (inhibition > 50% as compared to normal serum was detected in 45% of the pregnant women who had at least 1 previous parity, in 8% of the primigravidea, in 29% of those with one abortion and in 58% of those with more than one abortion. CONCLUSION: MLC inhibitory serum factor does not seem to be an essential factor for pregnancy development. Therefore, it should not be considered as a parameter for the assessment of RSA patients.

Inhibitory effects of selected Turkish spices and oregano components on some foodborne fungi.

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Akgül, A; Kivanç, M

1988-05-01

The inhibitory effects of 10 selected Turkish spices, oregano essential oil, thymol and carvacrol towards growth of 9 foodborne fungi were investigated in culture media with pH 3.5 and 5.5. The antifungal effects of sodium chloride, sorbic acid and sodium benzoate and the combined use of oregano with sodium chloride were also tested under the same conditions for comparison. Of the spices tested, only sodium chloride were also tested under the same conditions for comparison. Of the spices tested, only oregano at 1.0, 1.5, 2.0% (w/v) levels showed effect on all fungi. 8% (w/v) sodium chloride was less effective than oregano. Oregano essential oil, thymol or carvacrol at concentrations of 0.025% and 0.05% completely inhibited the growth of all fungi, showing greater inhibition than sorbic acid at the same concentrations. The combined use of oregano and sodium chloride exhibited a synergistic antifungal effect.

Inhibitory effects of crude extracts from several plants on postharvest pathogens of citrus

Science.gov (United States)

Gong, Mingfu; Guan, Qinlan; Xu, Shanshan

2018-04-01

China is one of the most important origin of citrus. Enormous economic losses was caused by fungal diseases in citrus harvest storage every year. The effective antimicrobial substances of garlic, ginger, celery and pepper were extracted by ethanol extraction and water extraction respectively. The inhibitory effects of the crude extract on Penicillium sp. caused fungal diseases in citrus harvest storage were also determined. The results showed that the extracts of garlic, ginger and celery had inhibitory effect on P. sp., but the extracts of pepper had no inhibitory effect on P. sp.. The garlic ethanol extracts had the best inhibitory effect on P. citrinum.

Comparative studies of antimycotic potential of thyme and clove oil ...

African Journals Online (AJOL)

fluconazole and ketoconazole against Candida albicans in vitro. This is necessary if oil extracts can replace antifungal antibiotics as agents for the treatment of candidiasis. The minimal inhibitory concentrations (MICs) of the essential oils were determined by first solubilizing them with dimethyl sulphoxide (DMSO) followed ...

Fermentation characteristics of Fusarium oxysporum grown on acetate

DEFF Research Database (Denmark)

Panagiotou, Gianni; Pachidou, Fotini; Petroutsos, Dimitris

2008-01-01

In this study, the growth characteristics of Fusarium oxysporum were evaluated in minimal medium using acetate or different mixtures of acetate and glucose as carbon source. The minimum inhibitory concentration (MIC) of acetic acid that F oxysporum cells could tolerate was 0.8% w/v while glucose ...

Inhibitory effect of 2‑mercaptoethane sulfonate on the formation of Escherichia coli biofilms in vitro.

Science.gov (United States)

Chen, Sheng; He, Nianhai; Yu, Jialin; Li, Luquan; Sun, Fengjun; Hu, Ying; Deng, Rui; Zhong, Shiming; Shen, Leilei

2015-10-01

The biofilms (BF) formed by Escherichia coli (E. coli) is an important cause of chronic and recurrent infections due to its capacity to persist on medical surfaces and indwelling devices, demonstrating the importance of inhibiting the formation of E. coli BF and reducing BF infection. Although 2‑mercaptoethane sulfonate (MESNA) exhibits a marked mucolytic effect clinically, the effect of MESNA on the inhibition of E. coli BF formation remains to be elucidated. The present study investigated whether MESNA inhibits the formation of E. coli BF in vitro. The minimum inhibitory concentration of MESNA on E. coli was determined to be 10 mg/ml. Subsequently, the effect of MESNA on BF early adhesion, extracellular polysaccharide (EPS) and extracellular protein were detected. The effect of a subinhibitory concentration of MESNA on BF formation was evaluated, and the inhibitory potency of MESNA against matured BF was assayed. The results revealed that MESNA inhibited early stage adhesion and formation of the E. coli BF, destroyed the mature BF membrane and reduced the EPS and extracellular proteins levels of the BF. In addition, the present study investigated the effects of MESNA on the expression of EPS‑ and adhesion protein‑associated genes using quantitative polymerase chain reaction analysis, which demonstrated that MESNA effectively inhibited the expression of these genes. These results suggested that MESNA possesses anti‑BF formation capability on E. coli in vitro and may be used as a potential reagent for the clinical treatment of E. coli BF‑associated infections.

NK cell activation: distinct stimulatory pathways counterbalancing inhibitory signals.

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Bakker, A B; Wu, J; Phillips, J H; Lanier, L L

2000-01-01

A delicate balance between positive and negative signals regulates NK cell effector function. Activation of NK cells may be initiated by the triggering of multiple adhesion or costimulatory molecules, and can be counterbalanced by inhibitory signals induced by receptors for MHC class I. A common pathway of inhibitory signaling is provided by immunoreceptor tyrosine-based inhibitory motifs (ITIMs) in the cytoplasmic domains of these receptors which mediate the recruitment of SH2 domain-bearing tyrosine phosphate-1 (SHP-1). In contrast to the extensive progress that has been made regarding the negative regulation of NK cell function, our knowledge of the signals that activate NK cells is still poor. Recent studies of the activating receptor complexes have shed new light on the induction of NK cell effector function. Several NK receptors using novel adaptors with immunoreceptor tyrosine-based activation motifs (ITAMs) and with PI 3-kinase recruiting motifs have been implicated in NK cell stimulation.

Dissociable Fronto-Operculum-Insula Control Signals for Anticipation and Detection of Inhibitory Sensory Cue.

Science.gov (United States)

Cai, Weidong; Chen, Tianwen; Ide, Jaime S; Li, Chiang-Shan R; Menon, Vinod

2017-08-01

The ability to anticipate and detect behaviorally salient stimuli is important for virtually all adaptive behaviors, including inhibitory control that requires the withholding of prepotent responses when instructed by external cues. Although right fronto-operculum-insula (FOI), encompassing the anterior insular cortex (rAI) and inferior frontal cortex (rIFC), involvement in inhibitory control is well established, little is known about signaling mechanisms underlying their differential roles in detection and anticipation of salient inhibitory cues. Here we use 2 independent functional magnetic resonance imaging data sets to investigate dynamic causal interactions of the rAI and rIFC, with sensory cortex during detection and anticipation of inhibitory cues. Across 2 different experiments involving auditory and visual inhibitory cues, we demonstrate that primary sensory cortex has a stronger causal influence on rAI than on rIFC, suggesting a greater role for the rAI in detection of salient inhibitory cues. Crucially, a Bayesian prediction model of subjective trial-by-trial changes in inhibitory cue anticipation revealed that the strength of causal influences from rIFC to rAI increased significantly on trials in which participants had higher anticipation of inhibitory cues. Together, these results demonstrate the dissociable bottom-up and top-down roles of distinct FOI regions in detection and anticipation of behaviorally salient cues across multiple sensory modalities. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

DRG axon elongation and growth cone collapse rate induced by Sema3A are differently dependent on NGF concentration.

Science.gov (United States)

Kaselis, Andrius; Treinys, Rimantas; Vosyliūtė, Rūta; Šatkauskas, Saulius

2014-03-01

Regeneration of embryonic and adult dorsal root ganglion (DRG) sensory axons is highly impeded when they encounter neuronal growth cone-collapsing factor semaphorin3A (Sema3A). On the other hand, increasing evidence shows that DRG axon's regeneration can be stimulated by nerve growth factor (NGF). In this study, we aimed to evaluate whether increased NGF concentrations can counterweight Sema3A-induced inhibitory responses in 15-day-old mouse embryo (E15) DRG axons. The DRG explants were grown in Neurobasal-based medium with different NGF concentrations ranging from 0 to 100 ng/mL and then treated with Sema3A at constant 10 ng/mL concentration. To evaluate interplay between NGF and Sema3A number of DRG axons, axon outgrowth distance and collapse rate were measured. We found that the increased NGF concentrations abolish Sema3A-induced inhibitory effect on axon outgrowth, while they have no effect on Sema3A-induced collapse rate.

Antimicrobial Peptide Trichokonin VI-Induced Alterations in the Morphological and Nanomechanical Properties of Bacillus subtilis

OpenAIRE

Su, Hai-Nan; Chen, Zhi-Hua; Song, Xiao-Yan; Chen, Xiu-Lan; Shi, Mei; Zhou, Bai-Cheng; Zhao, Xian; Zhang, Yu-Zhong

2012-01-01

Antimicrobial peptides are promising alternative antimicrobial agents compared to conventional antibiotics. Understanding the mode of action is important for their further application. We examined the interaction between trichokonin VI, a peptaibol isolated from Trichoderma pseudokoningii, and Bacillus subtilis, a representative Gram-positive bacterium. Trichokonin VI was effective against B. subtilis with a minimal inhibitory concentration of 25 µM. Trichokonin VI exhibited a concentration- ...

Chemical investigation of Cyperus distans L. and inhibitory activity of scabequinone in seed germination and seedling growth bioassays.

Science.gov (United States)

Vilhena, Karyme S S; Guilhon, Giselle Maria Skelding Pinheiro; Zoghbi, Maria das Graças B; Santos, Lourivaldo Silva; Souza Filho, Antonio Pedro Silva

2014-01-01

Chemical investigation of the rhizomes of Cyperus distans (Cyperaceae) led to the identification of α-ciperone, cyperotundone and scabequinone, besides other common constituents. Complete assignment of the (13)C NMR data of scabequinone is being published for the first time. The inhibitory effects of C. distans extracts and scabequinone on the seed germination and seedling growth of Mimosa pudica, Senna obtusifolia and Pueraria phaseoloides were evaluated. Seed germination inhibition bioassay revealed that S. obtusifolia (52-53%) was more sensitive to the hexane and the methanol extracts at 1% than M. pudica (0-10%). Scabequinone at 250 mg L⁻¹ displayed seed germination inhibitions more than 50% and radicle growth reduction of more than 35% of the test species S. obtusifolia and P. phaseoloides, while the hypocotyl growth of M. pudica was significantly affected (>50%) by the quinone at the same concentration. These results demonstrate that scabequinone contributes to the overall inhibitory activities of C. distans.

Regression analysis and categorical agreement of fluconazole disk zone diameters and minimum inhibitory concentration by broth microdilution of clinical isolates of Candida.

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Aggarwal, P; Kashyap, B

2017-06-01

Rampant use of fluconazole in Candida infections has led to predominance of less susceptible non-albicans Candida over Candida albicans. The aim of the study was to determine if zone diameters around fluconazole disk can be used to estimate the minimum inhibitory concentration (MIC) for clinical isolates of Candida species and vice versa. Categorical agreement between the Clinical & Laboratory Standards Institute (CLSI) recommended disk diffusion and CLSI broth microdilution method was sought for. Antifungal susceptibility testing by disk diffusion and Broth microdilution was done as per CLSI document M44-S3 and CLSI document M27-S4 for Candida isolates respectively. Regression analysis correlating zone diameters to MIC value was done. Pearson's correlation coefficient was calculated to determine correlation between disk zone diameters and MICs. Candida albicans (33.3%) was clearly outnumbered by other non-albicans species predominantly Candida tropicalis (42.5%) and Candida glabrata (18.4%). Ten percent of the strains were resistant to fluconazole by disk diffusion and 13% by broth microdilution. MIC range for Candida albicans and Candida tropicalis ranged from≤0.25-64μg/ml while that of Candida glabrata ranged from≤0.25-128μg/ml. Categorical agreement between disk diffusion and broth microdilution was 86.8%. Pearson's coefficient of correlation was -0.5975 indicating moderate negative correlation between the two variables. Zone sizes can be used to estimate the MIC values, although with limited accuracy. There should be a constant effort to upgrade the guidelines in view of new clinical data, and laboratories should make an active effort to incorporate them. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Determinants of aggressive behavior: Interactive effects of emotional regulation and inhibitory control.

Directory of Open Access Journals (Sweden)

I-Ju Hsieh

Full Text Available Aggressive behavior can be defined as any behavior intended to hurt another person, and it is associated with many individual and social factors. This study examined the relationship between emotional regulation and inhibitory control in predicting aggressive behavior. Seventy-eight participants (40 males completed self-report measures (Negative Mood Regulation Scale and Buss-Perry Aggression Questionnaire, a stop signal task, and engaged in a modified version of Taylor Aggression Paradigm (TAP exercise, in which the outcome was used as a measure of direct physical aggression. We used a hierarchical, mixed-model multiple regression analysis test to examine the effects of emotion regulation and inhibitory control on physical reactive aggression. Results indicated an interaction between emotion regulation and inhibitory control on aggression. For participants with low inhibitory control only, there was a significant difference between high and low emotion regulation on aggression, such that low emotion regulation participants registered higher aggression than high emotion regulation participants. This difference was not found among participants with high inhibitory control. These results have implications for refining and targeting training and rehabilitation programs aimed at reducing aggressive behavior.

Increased beta rhythm as an indicator of inhibitory mechanisms in tourette syndrome

DEFF Research Database (Denmark)

Niccolai, Valentina; van Dijk, Hanneke; Franzkowiak, Stephanie

2016-01-01

BACKGROUND: Inhibitory oscillatory mechanisms subserving tic compensation have been put forward in Tourette syndrome. Modulation of the beta rhythm (15-25 Hz) as the well-established oscillatory movement execution-inhibition indicator was tested during a cognitive-motor task in patients with Tour......BACKGROUND: Inhibitory oscillatory mechanisms subserving tic compensation have been put forward in Tourette syndrome. Modulation of the beta rhythm (15-25 Hz) as the well-established oscillatory movement execution-inhibition indicator was tested during a cognitive-motor task in patients...... in parieto-occipital brain regions contralaterally to the response hand. Average beta power and power gain correlated negatively with tic severity. CONCLUSIONS: Increased motor inhibitory as well as visuomotor attentional processes are likely to subserve tic compensation. Correlational results suggest...... that stronger inhibitory compensation accompanies less tic severity. © 2016 International Parkinson and Movement Disorder Society....

Growth inhibition of Listeria spp. on Camembert cheese by bacteria producing inhibitory substances.

Science.gov (United States)

Sulzer, G; Busse, M

1991-12-01

Bacterial strains exhibiting antimicrobial activity towards other bacteria are quite common in nature. During the past few years several genera have been shown to exert inhibitory action against Listeria. spp. In the present work strains of Enterococcus, Lactobacillus and Lactococcus were tested for their influence on the development of Listeria spp. on Camembert cheese. Partial or complete inhibition of growth of Listeria spp. was observed using various inhibitory bacteria. Complete inhibition occurred when the inhibitory strain was used as a starter culture and there was a low level of contamination with Listeria spp. during the first stage of ripening. Very little inhibition occurred if the inhibitory strain was added together with the starter culture.

Characterisation of inhibitory substances produced by two Pseudoalteromonas species and the cyanobacterial strain Flo1

OpenAIRE

Rau, Jan Erik

2011-01-01

In the present study the inhibitory substances of P. aurantia NCIMB 2052T and P. citrea NCIMB 1889T were investigated with respect to their substantial and functional nature, their inhibitory potential, their stability against various treatments as well as the growth phases and incubation conditions when the substances are produced. In addition, an inhibitory substance produced by strain Flo1 was examined regarding its structure, function, and inhibitory potential. Furthermore, its taxonomic ...

Angiotensin converting enzyme (ACE) inhibitory and antihypertensive activities of protein hydrolysate from meat of Kacang goat (Capra aegagrus hircus).

Science.gov (United States)

Mirdhayati, Irdha; Hermanianto, Joko; Wijaya, Christofora H; Sajuthi, Dondin; Arihara, Keizo

2016-08-01

The meat of Kacang goat has potential for production of a protein hydrolysate. Functional ingredients from protein hydrolysate of Kacang goat meat were determined by the consistency of angiotensin-converting enzyme (ACE) inhibitory activity and antihypertensive effect. This study examined the potency of Kacang goat protein hydrolysate in ACE inhibition and antihypertensive activity. Protein hydrolysates of Kacang goat meat were prepared using sequential digestion of endo-proteinase and protease complex at several concentrations and hydrolysis times. The highest ACE inhibitory activity resulted from a hydrolysate that was digested for 4 h with 5 g kg(-1) of both enzymes. An ACE inhibitory peptide was purified and a novel peptide found with a sequence of Phe-Gln-Pro-Ser (IC50 value of 27.0 µmol L(-1) ). Both protein hydrolysates and a synthesised peptide (Phe-Gln-Pro-Ser) demonstrated potent antihypertensive activities in spontaneously hypertensive rats. Protein hydrolysate of Kacang goat meat produced by sequential digestion with endo-proteinase and protease complex has great potential as a functional ingredient, particularly as an antihypertensive agent. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Characterization of the Raf kinase inhibitory protein (RKIP) binding pocket: NMR-based screening identifies small-molecule ligands.

Science.gov (United States)

Shemon, Anne N; Heil, Gary L; Granovsky, Alexey E; Clark, Mathew M; McElheny, Dan; Chimon, Alexander; Rosner, Marsha R; Koide, Shohei

2010-05-05

Raf kinase inhibitory protein (RKIP), also known as phoshaptidylethanolamine binding protein (PEBP), has been shown to inhibit Raf and thereby negatively regulate growth factor signaling by the Raf/MAP kinase pathway. RKIP has also been shown to suppress metastasis. We have previously demonstrated that RKIP/Raf interaction is regulated by two mechanisms: phosphorylation of RKIP at Ser-153, and occupation of RKIP's conserved ligand binding domain with a phospholipid (2-dihexanoyl-sn-glycero-3-phosphoethanolamine; DHPE). In addition to phospholipids, other ligands have been reported to bind this domain; however their binding properties remain uncharacterized. In this study, we used high-resolution heteronuclear NMR spectroscopy to screen a chemical library and assay a number of potential RKIP ligands for binding to the protein. Surprisingly, many compounds previously postulated as RKIP ligands showed no detectable binding in near-physiological solution conditions even at millimolar concentrations. In contrast, we found three novel ligands for RKIP that specifically bind to the RKIP pocket. Interestingly, unlike the phospholipid, DHPE, these newly identified ligands did not affect RKIP binding to Raf-1 or RKIP phosphorylation. One out of the three ligands displayed off target biological effects, impairing EGF-induced MAPK and metabolic activity. This work defines the binding properties of RKIP ligands under near physiological conditions, establishing RKIP's affinity for hydrophobic ligands and the importance of bulky aliphatic chains for inhibiting its function. The common structural elements of these compounds defines a minimal requirement for RKIP binding and thus they can be used as lead compounds for future design of RKIP ligands with therapeutic potential.

Characterization of the Raf kinase inhibitory protein (RKIP binding pocket: NMR-based screening identifies small-molecule ligands.

Directory of Open Access Journals (Sweden)

Anne N Shemon

2010-05-01

Full Text Available Raf kinase inhibitory protein (RKIP, also known as phoshaptidylethanolamine binding protein (PEBP, has been shown to inhibit Raf and thereby negatively regulate growth factor signaling by the Raf/MAP kinase pathway. RKIP has also been shown to suppress metastasis. We have previously demonstrated that RKIP/Raf interaction is regulated by two mechanisms: phosphorylation of RKIP at Ser-153, and occupation of RKIP's conserved ligand binding domain with a phospholipid (2-dihexanoyl-sn-glycero-3-phosphoethanolamine; DHPE. In addition to phospholipids, other ligands have been reported to bind this domain; however their binding properties remain uncharacterized.In this study, we used high-resolution heteronuclear NMR spectroscopy to screen a chemical library and assay a number of potential RKIP ligands for binding to the protein. Surprisingly, many compounds previously postulated as RKIP ligands showed no detectable binding in near-physiological solution conditions even at millimolar concentrations. In contrast, we found three novel ligands for RKIP that specifically bind to the RKIP pocket. Interestingly, unlike the phospholipid, DHPE, these newly identified ligands did not affect RKIP binding to Raf-1 or RKIP phosphorylation. One out of the three ligands displayed off target biological effects, impairing EGF-induced MAPK and metabolic activity.This work defines the binding properties of RKIP ligands under near physiological conditions, establishing RKIP's affinity for hydrophobic ligands and the importance of bulky aliphatic chains for inhibiting its function. The common structural elements of these compounds defines a minimal requirement for RKIP binding and thus they can be used as lead compounds for future design of RKIP ligands with therapeutic potential.

Minimizing 1/f Noise in Magnetic Sensors with a MEMS Flux Concentrator

National Research Council Canada - National Science Library

Edelstein, A. S; Fischer, Greg; Pulskamp, Jeff; Pedersen, Michael; Bernard, William; Cheng, Shu F

2004-01-01

.... This shift is accomplished by modulating the magnetic field before it reaches the sensor. In our device, the magnetic sensor, a GMR sensor, is placed between flux concentrators that have been deposited on MEMS flaps...

Hypocholesterolemic Effect and In Vitro Pancreatic Lipase Inhibitory Activity of an Opuntia ficus-indica Extract.

Science.gov (United States)

Padilla-Camberos, Eduardo; Flores-Fernandez, Jose Miguel; Fernandez-Flores, Ofelia; Gutierrez-Mercado, Yanet; Carmona-de la Luz, Joel; Sandoval-Salas, Fabiola; Mendez-Carreto, Carlos; Allen, Kirk

2015-01-01

Cholesterol control is fundamental for prevention of cardiovascular disorders. In this work, the hypocholesterolemic activity of an aqueous Opuntia ficus-indica extract (AOE) was tested in triton-induced mice. The inhibitory activity on pancreatic lipase enzyme was evaluated in vitro by the same extract. Furthermore, polyphenol content of the extract was evaluated. Hypercholesterolemia was induced in three groups of mice by intraperitoneal administration of Triton WR-1339. After induction of hypercholesterolemia, the groups were treated with an AOE (500 mg/kg) and saline solution and the positive control group with orlistat, respectively. Cholesterol levels were measured 24 h later in peripheral blood. The levels of blood cholesterol after administration of AOE significantly decreased compared to negative control. The inhibitory activity of AOE on pancreatic lipase enzyme was evaluated at concentrations from 60 to 1000 μg/mL. The AOE inhibited the pancreatic lipase with an IC50 = 588.5 μg/mL. The AOE had a high content of polyphenolic compounds. These results show that AOE is able to prevent hypercholesterolemia by pancreatic lipase inhibition, in part due to its polyphenolic compounds.

Hypocholesterolemic Effect and In Vitro Pancreatic Lipase Inhibitory Activity of an Opuntia ficus-indica Extract

Directory of Open Access Journals (Sweden)

Eduardo Padilla-Camberos

2015-01-01

Full Text Available Cholesterol control is fundamental for prevention of cardiovascular disorders. In this work, the hypocholesterolemic activity of an aqueous Opuntia ficus-indica extract (AOE was tested in triton-induced mice. The inhibitory activity on pancreatic lipase enzyme was evaluated in vitro by the same extract. Furthermore, polyphenol content of the extract was evaluated. Hypercholesterolemia was induced in three groups of mice by intraperitoneal administration of Triton WR-1339. After induction of hypercholesterolemia, the groups were treated with an AOE (500 mg/kg and saline solution and the positive control group with orlistat, respectively. Cholesterol levels were measured 24 h later in peripheral blood. The levels of blood cholesterol after administration of AOE significantly decreased compared to negative control. The inhibitory activity of AOE on pancreatic lipase enzyme was evaluated at concentrations from 60 to 1000 μg/mL. The AOE inhibited the pancreatic lipase with an IC50 = 588.5 μg/mL. The AOE had a high content of polyphenolic compounds. These results show that AOE is able to prevent hypercholesterolemia by pancreatic lipase inhibition, in part due to its polyphenolic compounds.

Sleep: The hebbian reinforcement of the local inhibitory synapses.

Science.gov (United States)

Touzet, Claude

2015-09-01

Sleep is ubiquitous among the animal realm, and represents about 30% of our lives. Despite numerous efforts, the reason behind our need for sleep is still unknown. The Theory of neuronal Cognition (TnC) proposes that sleep is the period of time during which the local inhibitory synapses (in particular the cortical ones) are replenished. Indeed, as long as the active brain stays awake, hebbian learning guarantees that efficient inhibitory synapses lose their efficiency – just because they are efficient at avoiding the activation of the targeted neurons. Since hebbian learning is the only known mechanism of synapse modification, it follows that to replenish the inhibitory synapses' efficiency, source and targeted neurons must be activated together. This is achieved by a local depolarization that may travel (wave). The period of time during which such slow waves are experienced has been named the "slow-wave sleep" (SWS). It is cut into several pieces by shorter periods of paradoxical sleep (REM) which activity resembles that of the awake state. Indeed, SWS – because it only allows local neural activation – decreases the excitatory long distance connections strength. To avoid losing the associations built during the awake state, these long distance activations are played again during the REM sleep. REM and SWS sleeps act together to guarantee that when the subject awakes again, his inhibitory synaptic efficiency is restored and his (excitatory) long distance associations are still there. Copyright © 2015 Elsevier Ltd. All rights reserved.

Sex Differences in How Erotic and Painful Stimuli Impair Inhibitory Control

Science.gov (United States)

Yu, Jiaxin; Hung, Daisy L.; Tseng, Philip; Tzeng, Ovid J. L.; Muggleton, Neil G.; Juan, Chi-Hung

2012-01-01

Witnessing emotional events such as arousal or pain may impair ongoing cognitive processes such as inhibitory control. We found that this may be true only half of the time. Erotic images and painful video clips were shown to men and women shortly before a stop signal task, which measures cognitive inhibitory control. These stimuli impaired…

In vitro inhibitory effects of plumbagin, the promising antimalarial candidate, on human cytochrome P450 enzymes.

Science.gov (United States)

Sumsakul, Wiriyaporn; Chaijaroenkul, Wanna; Na-Bangchang, Kesara

2015-11-01

To investigate the propensity of plumbagin to inhibit the three isoforms of human cytochrome P450 (CYP), i.e., CYP1A2, CYP2C19, and CYP3A4 using human liver microsomes in vitro. Inhibitory effects of plumbagin on the three human CYP isoforms were investigated using pooled human liver microsomes. Phenacetin O-deethylation, omeprazole hydroxylation and nifedipine oxidation were used as selective substrates for CYP1A2, CYP2C19 and CYP3A4 activities, respectively. Concentrations of paracetamol, 5-hydroxyomeprazole, and oxidized nifedipine were determined in microsomal incubation mixture using high-performance liquid chromatography. Plumbagin showed significant inhibitory effects on all CYP isoforms, but with the most potent activity on CYP2C19-mediated omeprazole hydroxylation. The IC50 (concentration that inhibits enzyme activity by 50%) values of plumbagin and nootkatone (selective inhibitor) for CYP2C19 were (0.78 ± 0.01) and (27.31 ± 0.66) μM, respectively. The inhibitory activities on CYP1A2-mediated phenacetin O-deethylation and CYP3A4-mediated nifedipine oxidation were moderate. The IC50 values of plumbagin and α-naphthoflavone (selective inhibitor) for CYP1A2 were (1.39 ± 0.01) and (0.02 ± 0.36) μM, respectively. The corresponding IC50 values of plumbagin and ketoconazole (selective inhibitor) for CYP3A4 were (2.37 ± 0.10) and (0.18 ± 0.06) μM, respectively. Clinical relevance of the interference of human drug metabolizing enzymes should be aware of for further development scheme of plumbagin as antimalarial drug when used in combination with other antimalarial drugs which are metabolized by these CYP isoforms. Copyright © 2015 Hainan Medical College. Production and hosting by Elsevier B.V. All rights reserved.

Inhibitory coherence in a heterogeneous population of subthreshold and suprathreshold type-I neurons

International Nuclear Information System (INIS)

Kim, Sang-Yoon; Hong, Duk-Geun; Kim, Jean; Lim, Woochang

2012-01-01

We study inhibitory coherence (i.e. collective coherence by synaptic inhibition) in a population of globally coupled type-I neurons, which can fire at arbitrarily low frequency. No inhibitory coherence is observed in a homogeneous population composed of only subthreshold neurons, which exhibit noise-induced firings. In addition to subthreshold neurons, there exist spontaneously firing suprathreshold neurons in a noisy environment of a real brain. To take into consideration the effect of suprathreshold neurons on inhibitory coherence, we consider a heterogeneous population of subthreshold and suprathreshold neurons and investigate the inhibitory coherence by increasing the fraction of suprathreshold neurons P supra . As P supra passes a threshold P* supra , suprathreshold neurons begin to synchronize and play the role of coherent inhibitors for the emergence of inhibitory coherence. Thus, regularly oscillating population-averaged global potential appears for P supra > P* supra . For this coherent case, suprathreshold neurons exhibit sparse spike synchronization (i.e. individual potentials of suprathreshold neurons consist of coherent sparse spikings and coherent subthreshold small-amplitude hoppings). By virtue of their coherent inhibition, sparsely synchronized suprathreshold neurons suppress the noisy activity of subthreshold neurons. Thus, subthreshold neurons exhibit hopping synchronization (i.e. only coherent subthreshold hopping oscillations without spikings appear in the individual potentials of subthreshold neurons). We also characterize the inhibitory coherence in terms of the ‘statistical-mechanical’ spike-based and correlation-based measures, which quantify the average contributions of the microscopic individual spikes and individual potentials to the macroscopic global potential. Finally, the effect of sparse randomness of synaptic connectivity on the inhibitory coherence is briefly discussed. (paper)

In vitro synergy of baicalein and gentamicin against vancomycin-resistant Enterococcus.

Science.gov (United States)

Chang, Ping Chin; Li, Hua Yu; Tang, Hung Jen; Liu, Jien Wei; Wang, Jhi Joung; Chuang, Yin Ching

2007-02-01

Little is known about the possible synergism of baicalein, a bioactive flavone of Scutellariae radix (a Chinese herb), when used in conjunction with other antimicrobial agents against vancomycin-resistant Enterococcus (VRE). This in vitro study examined the possible synergism of the combination of baicalein and gentamicin against VRE. Minimal inhibitory concentrations (MICs) of baicalein as well as gentamicin were determined against 39 clinical isolates of VRE by the agar dilution method. Synergistic activities were determined using the checkerboard method based on the fractional inhibitory concentration indices and also the time-kill method. Further time-kill studies were conducted with these two agents against one randomly chosen clinical isolate, VRE-096. Minimal concentrations inhibiting 50% (MIC(50)) and 90% (MIC(90)) of isolates for baicalein and gentamicin were all >256 microg/mL. Synergism between baicalein and gentamicin was demonstrated against four clinical isolates of VRE (VRE-70, VRE-940, VRE-096 and VRE-721). When approximately 5 x 10(5) colony-forming units/mL of VRE-096 was incubated with both baicalein at a concentration of 32 microg/mL (1/8 x MIC) and gentamicin at a concentration of 128 microg/mL (1/2 x MIC), there was an inhibitory effect against VRE that persisted for 48 h. At 48 h, the combination of baicalein and gentamicin at these respective concentrations resulted in a reduction of growth by approximately 2 orders of magnitude compared to that for the starting inoculum and by 3 orders of magnitude compared to that for baicalein alone, the more active single agent. This study demonstrated that baicalein and gentamicin can act synergistically in inhibiting VRE in vitro.

Pythium insidiosum: inhibitory effects of propolis and geopropolis on hyphal growth

OpenAIRE

Araújo, Maria José Abigail Mendes; Bosco, Sandra de Moraes Gimenes; Sforcin, José Maurício

2016-01-01

Abstract Propolis and geopropolis are resinous products of bees showing antimicrobial effects. There is no data concerning their action against Pythium insidiosum - the causative agent of pythiosis, a pyogranulomatous disease of the subcutaneous tissue that affects mostly horses, dogs and humans. Fragments of 15 isolates of P. insidiodum were incubated with propolis and geopropolis extracts and evaluated for up to seven days to detect the minimal fungicidal concentration (MFC). Propolis inhib...

Concentrating Genomic Length DNA in a Microfabricated Array

DEFF Research Database (Denmark)

Chen, Yu; Abrams, Ezra S.; Boles, T. Christian

2015-01-01

the DNA molecules to minimal coil size using polyethylene glycol (PEG) derived depletion forces. We map out the sweet spot, where concentration occurs, as a function of PEG concentration and flow speed using a combination of theoretical analysis and experiment. Purification of DNA from enzymatic reactions...

Advanced Purex process and waste minimization at La Hague

International Nuclear Information System (INIS)

Masson, H.; Nouguier, H.; Bernard, C.; Runge, S.

1993-01-01

After a brief recall of the different aspects of the commercial irradiated fuel reprocessing, this paper presents the achievements of the recently commissioned UP3 plant at La Hague. The advanced Purex process implemented with a total waste management results in important waste volume minimization, so that the total volume of high-level and transuranic waste is lower than what it would be in a once-through cycle. Moreover, further minimization is still possible, based on an improved waste management. Cogema has launched the necessary program, which will lead to an overall volume of HLW and TRU wastes of less than 1 m 3 /t by the end of the decade, the maximum possible activity being concentrated in the glass

An investigation into the inhibitory function of serotonin in diffuse noxious inhibitory controls in the neuropathic rat.

Science.gov (United States)

Bannister, K; Lockwood, S; Goncalves, L; Patel, R; Dickenson, A H

2017-04-01

Following neuropathy α2-adrenoceptor-mediated diffuse noxious inhibitory controls (DNIC), whereby a noxious conditioning stimulus inhibits the activity of spinal wide dynamic range (WDR) neurons, are abolished, and spinal 5-HT7 receptor densities are increased. Here, we manipulate spinal 5-HT content in spinal nerve ligated (SNL) animals and investigate which 5-HT receptor mediated actions predominate. Using in vivo electrophysiology we recorded WDR neuronal responses to von frey filaments applied to the hind paw before, and concurrent to, a noxious ear pinch (the conditioning stimulus) in isoflurane-anaesthetised rats. The expression of DNIC was quantified as a reduction in WDR neuronal firing in the presence of conditioning stimulus and was investigated in SNL rats following spinal application of (1) selective serotonin reuptake inhibitors (SSRIs) citalopram or fluoxetine, or dual application of (2) SSRI plus 5-HT7 receptor antagonist SB269970, or (3) SSRI plus α2 adrenoceptor antagonist atipamezole. DNIC were revealed in SNL animals following spinal application of SSRI, but this effect was abolished upon joint application of SSRI plus SB269970 or atipamezole. We propose that in SNL animals the inhibitory actions (quantified as the presence of DNIC) of excess spinal 5-HT (presumed present following application of SSRI) were mediated via 5-HT7 receptors. The anti-nociception depends upon an underlying tonic noradrenergic inhibitory tone via the α2-adrenoceptor. Following neuropathy enhanced spinal serotonin availability switches the predominant spinal 5-HT receptor-mediated actions but also alters noradrenergic signalling. We highlight the therapeutic complexity of SSRIs and monoamine modulators for the treatment of neuropathic pain. © 2016 European Pain Federation - EFIC®.

Minimally invasive orthognathic surgery.

Science.gov (United States)

Resnick, Cory M; Kaban, Leonard B; Troulis, Maria J

2009-02-01

Minimally invasive surgery is defined as the discipline in which operative procedures are performed in novel ways to diminish the sequelae of standard surgical dissections. The goals of minimally invasive surgery are to reduce tissue trauma and to minimize bleeding, edema, and injury, thereby improving the rate and quality of healing. In orthognathic surgery, there are two minimally invasive techniques that can be used separately or in combination: (1) endoscopic exposure and (2) distraction osteogenesis. This article describes the historical developments of the fields of orthognathic surgery and minimally invasive surgery, as well as the integration of the two disciplines. Indications, techniques, and the most current outcome data for specific minimally invasive orthognathic surgical procedures are presented.

Model Arrhenius untuk Pendugaan Laju Respirasi Brokoli Terolah Minimal

Directory of Open Access Journals (Sweden)

Nurul Imamah

2016-04-01

Full Text Available Minimally processed broccoli are perishable product because it still has some metabolism process during the storage period. One of the metabolism process is respiration. Respiration rate is varied depend on the commodity and storage temperature. The purpose of this research are: to review the respiration pattern of minimally processed broccoli during storage period, to study the effect of storage temperature to respiration rate, and to review the correlation between respiration rate and temperature based on Arrhenius model. Broccoli from farming organization “Agro Segar” was processed minimally and then measure the respiration rate. Closed system method is used to measure O2 and CO2 concentration. Minimally processed broccoli is stored at a temperature of 0oC, 5oC, 10oC and 15oC. The experimental design used was completely randomized design of the factors to analyze the rate of respiration. The result shows that broccoli is a climacteric vegetable. It is indicated by the increasing of O2 consumption and CO2 production during senescence phase. The respiration rate increase as high as the increasing of temperature storage. Models Arrhenius can describe correlation between respiration rate and temperature with R2 = 0.953-0.947. The constant value of activation energy (Eai and pre-exponential factor (Roi from Arrhenius model can be used to predict the respiration rate of minimally processed broccoli in every storage temperature

Regularity of Minimal Surfaces

CERN Document Server

Dierkes, Ulrich; Tromba, Anthony J; Kuster, Albrecht

2010-01-01

"Regularity of Minimal Surfaces" begins with a survey of minimal surfaces with free boundaries. Following this, the basic results concerning the boundary behaviour of minimal surfaces and H-surfaces with fixed or free boundaries are studied. In particular, the asymptotic expansions at interior and boundary branch points are derived, leading to general Gauss-Bonnet formulas. Furthermore, gradient estimates and asymptotic expansions for minimal surfaces with only piecewise smooth boundaries are obtained. One of the main features of free boundary value problems for minimal surfaces is t

Assessment of Minimal HE (with emphasis on computerized psychometric tests)

Science.gov (United States)

Kappus, Matthew R; Bajaj, Jasmohan S

2012-01-01

Synopsis Minimal hepatic encephalopathy (MHE) is associated with a high risk of development of overt hepatic encephalopathy, impaired quality of life and driving accidents. The detection of MHE requires specialized testing since it cannot by definition, be diagnosed on standard clinical examination. Psychometric (paper-pencil or computerized or a combination) and neuro-physiological techniques are often used to test for MHE. Paper-pencil psychometric batteries like the Psychometric Hepatic Encephalopathy Score (PHES) have been validated in several countries but do not have US normative values. Computerized tests such as the inhibitory control test (ICT), cognitive drug research system and Scan test have proven useful to diagnose MHE and predict outcomes. The specificity and sensitivity of these tests are similar to the recommended gold standards. Neuro-physiological tests such as the EEG and its interpretations, evoked potentials and Critical Flicker Frequency (CFF) also provide useful information. The diagnosis of MHE is an important issue for clinicians and patients alike and the testing strategies depend on the normative data available, patient comfort and local expertise. PMID:22321464

Inhibitory neurotransmission and olfactory memory in honeybees.

Science.gov (United States)

El Hassani, Abdessalam Kacimi; Giurfa, Martin; Gauthier, Monique; Armengaud, Catherine

2008-11-01

In insects, gamma-aminobutyric acid (GABA) and glutamate mediate fast inhibitory neurotransmission through ligand-gated chloride channel receptors. Both GABA and glutamate have been identified in the olfactory circuit of the honeybee. Here we investigated the role of inhibitory transmission mediated by GABA and glutamate-gated chloride channels (GluCls) in olfactory learning and memory in honeybees. We combined olfactory conditioning with injection of ivermectin, an agonist of GluCl receptors. We also injected a blocker of glutamate transporters (L-trans-PDC) or a GABA analog (TACA). We measured acquisition and retention 1, 24 and 48 h after the last acquisition trial. A low dose of ivermectin (0.01 ng/bee) impaired long-term olfactory memory (48 h) while a higher dose (0.05 ng/bee) had no effect. Double injections of ivermectin and L-trans-PDC or TACA had different effects on memory retention, depending on the doses and agents combined. When the low dose of ivermectin was injected after Ringer, long-term memory was again impaired (48 h). Such an effect was rescued by injection of both TACA and L-trans-PDC. A combination of the higher dose of ivermectin and TACA decreased retention at 48 h. We interpret these results as reflecting the involvement of both GluCl and GABA receptors in the impairment of olfactory long-term memory induced by ivermectin. These results illustrate the diversity of inhibitory transmission and its implication in long-term olfactory memory in honeybees.

Evaluation of a Standardized Extract from Morus alba against α-Glucosidase Inhibitory Effect and Postprandial Antihyperglycemic in Patients with Impaired Glucose Tolerance: A Randomized Double-Blind Clinical Trial

Science.gov (United States)

Hwang, Seung Hwan; Li, Hong Mei; Wang, Zhiqiang

2016-01-01

To evaluate the antihyperglycemic effect of a standardized extract of the leaves of Morus alba (SEMA), the present study was designed to investigate the α-glucosidase inhibitory effect and acute single oral toxicity as well as evaluate blood glucose reduction in animals and in patients with impaired glucose tolerance in a randomized double-blind clinical trial. SEMA was found to inhibit α-glucosidase at a fourfold higher level than the positive control (acarbose), in a concentration-dependent manner. Moreover, blood glucose concentration was suppressed by SEMA in vivo. Clinical signs and weight changes were observed when conducting an evaluation of the acute toxicity of SEMA through a single-time administration, with clinical observation conducted more than once each day. After administration of the SEMA, observation was for 14 days; all of the animals did not die and did not show any abnormal symptoms. In addition, the inhibitory effects of rice coated with SEMA were evaluated in a group of impaired glucose tolerance patients on postprandial glucose and a group of normal persons, and results showed that SEMA had a clear inhibitory effect on postprandial hyperglycemia in both groups. Overall, SEMA showed excellent potential in the present study as a material for improving postprandial hyperglycemia. PMID:27974904

[Inhibitory effect of kaempferol on inflammatory response of lipopolysaccharide-stimulated human mast cells].

Science.gov (United States)

Zhou, Yun-jiang; Wang, Hu; Li, Li; Sui, He-huan; Huang, Jia-jun

2015-06-01

This study is to investigate the inhibitory effect of kaempferol on inflammatory response of lipopolysaccharide(LPS)-stimulated HMC-1 mast cells. The cytotoxicity of kaempferol to HMC-1 mast cells were analyzed by using MTT assay and then the administration concentrations of kaempferol were established. Histamine, IL-6, IL-8, IL-1β and TNF-α were measured using ELISA assay in activated HMC-1 mast cells after incubation with various concentrations of kaempferol (10, 20 and 40 µmol.L-1). Western blot was used to test the protein expression of p-IKKβ, IκBα, p-IκBα and nucleus NF-κB of LPS-induced HMC-1 mast cells after incubation with different concentrations of kaempferol. The optimal concentrations of kaempferol were defined as the range from 5 µmol.L-1 to 40 µmol.L-1. Kaempferol significantly decreased the release of histamine, IL-6, IL-8, IL-1β and TNF-α of activated HMC-1 mast cells (Pkaempferol, the protein expression of p-IKKβ, p-IKBa and nucleus NF-κB (p65) markedly reduced in LPS-stimulated HMC-1 mast cells (Pkaempferol markedly inhibit mast cell-mediated inflammatory response. At the same time, kaempferol can inhibit the activation of IKKβ, block the phosphorylation of IκBα, prevent NF-KB entering into the nucleus, and then decrease the release of inflammatory mediators.

NMDAR-mediated calcium transients elicited by glutamate co-release at developing inhibitory synapses

Directory of Open Access Journals (Sweden)

Abigail Kalmbach

2010-07-01

Full Text Available Before hearing onset, the topographic organization of the inhibitory sound localization pathway from the medial nucleus of the trapezoid body (MNTB to the lateral superior olive (LSO is refined by means of synaptic silencing and strengthening. During this refinement period MNTB-LSO synapses not only release GABA and glycine but also release glutamate. This co-released glutamate can elicit postsynaptic currents that are predominantly mediated by NMDA receptors (NMDARs. To gain a better understanding of how glutamate contributes to synaptic signaling at developing MNTB-LSO inhibitory synapse, we investigated to what degree and under what conditions NMDARs contribute to postsynaptic calcium responses. Our results demonstrate that MNTB-LSO synapses can elicit compartmentalized calcium responses along aspiny LSO dendrites. These responses are significantly attenuated by the NMDARs antagonist APV. APV, however, has no effect on somatically recorded electrical postsynaptic responses, indicating little, if any, contribution of NMDARs to spike generation. Small NMDAR-mediated calcium responses were also observed under physiological levels of extracellular magnesium concentrations indicating that MNTB-LSO synapses activate magnesium sensitive NMDAR on immature LSO dendrites. In Fura-2 AM loaded neurons, blocking GABAA and glycine receptors decreased NMDAR contribution to somatic calcium responses suggesting that GABA and glycine, perhaps by shunting backpropagating action potentials, decrease the level of NMDAR activation under strong stimulus conditions.

Influence of temperature on the inhibitory potency of Eucalyptus honey against Candida albicans

Directory of Open Access Journals (Sweden)

Ahmed Moussa

2012-12-01

Full Text Available Objective: To evaluate the effects of heat processing on the antifungal activity of honey. Methods: A sample of the honey of eucalyptus was divided into four portions of 250 g each. One of the four portions obtained from studied honey was not heated (not heated fraction 25曟, the other portions were placed in water bath during 24 hours at 40 曟, 60 曟 and 80曟 temperatures. The HMF rates, Acidity, pH and the index of refraction were determined by harmonized methods. The antifungal tests (Minimum Inhibitory Concentration were carried out on Sabouraud agar medium embedded with honey according to dilution test. Results: The moisture shows values of 15.65% and 15.83%, pH between 4.10 and 4.24, the free acidity ranges between 33.8 and 38.36 meq kg-1, hydroxymethylfurfural (HMF content shows values between 28.8 and 103.44 mg kg-1. The antifungal action of the non-heated fraction (Fc of honey in vitro was marked 40 % (vol/vol than heated fractions of honey (42%, 44%, and 45% vol/vol. respectively The antifungal activity of each fraction decreased in the following order: Fct曘 25 > Fct曘 40 > Fct曘 60 > Fct曘 80]. Conclusion: our findings indicate that different levels of parameters physical-chemical properties of honey to different temperatures showed inhibitory activity against C. albicans with variable degrees.

Chemical Constituents of Malaysian U. cordata var. ferruginea and Their in Vitro α-Glucosidase Inhibitory Activities

Directory of Open Access Journals (Sweden)

Nur Hakimah Abdullah

2016-04-01

Full Text Available Continuing our interest in the Uncaria genus, the phytochemistry and the in-vitro α-glucosidase inhibitory activities of Malaysian Uncaria cordata var. ferruginea were investigated. The phytochemical study of this plant, which employed various chromatographic techniques including recycling preparative HPLC, led to the isolation of ten compounds with diverse structures comprising three phenolic acids, two coumarins, three flavonoids, a terpene and an iridoid glycoside. These constituents were identified as 2-hydroxybenzoic acid or salicylic acid (1, 2,4-dihydroxybenzoic acid (2, 3,4-dihydroxybenzoic acid (3, scopoletin or 7-hydroxy-6-methoxy-coumarin (4, 3,4-dihydroxy-7-methoxycoumarin (5, quercetin (6, kaempferol (7, taxifolin (8, loganin (9 and β-sitosterol (10. Structure elucidation of the compounds was accomplished with the aid of 1D and 2D Nuclear Magnetic Resonance (NMR spectral data and Ultraviolet-Visible (UV-Vis, Fourier Transform Infrared (FTIR spectroscopy and mass spectrometry (MS. In the α-glucosidase inhibitory assay, the crude methanolic extract of the stems of the plant and its acetone fraction exhibited strong α-glucosidase inhibition activity of 87.7% and 89.2%, respectively, while its DCM fraction exhibited only moderate inhibition (75.3% at a concentration of 1 mg/mL. The IC50 values of both fractions were found to be significantly lower than the standard acarbose suggesting the presence of potential α-glucosidase inhibitors. Selected compounds isolated from the active fractions were then subjected to α-glucosidase assay in which 2,4-dihydroxybenzoic acid and quercetin showed strong inhibitory effects against the enzyme with IC50 values of 549 and 556 μg/mL compared to acarbose (IC50 580 μg/mL while loganin and scopoletin only showed weak α-glucosidase inhibition of 44.9% and 34.5%, respectively. This is the first report of the isolation of 2-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid and loganin from the genus

Inhibitory control is not lateralized in Parkinson's patients.

Science.gov (United States)

Mirabella, G; Fragola, M; Giannini, G; Modugno, N; Lakens, Daniel

2017-07-28

Parkinson's disease (PD) is often characterized by asymmetrical symptoms, which are more prominent on the side of the body contralateral to the most extensively affected brain hemisphere. Therefore, lateralized PD presents an opportunity to examine the effects of asymmetric subcortical dopamine deficiencies on cognitive functioning. As it has been hypothesized that inhibitory control relies upon a right-lateralized pathway, we tested whether left-dominant PD (LPD) patients suffered from a more severe deficit in this key executive function than right-dominant PD patients (RPD). To this end, via a countermanding task, we assessed both proactive and reactive inhibition in 20 LPD and 20 RPD patients, and in 20 age-matched healthy subjects. As expected, we found that PD patients were significantly more impaired in both forms of inhibitory control than healthy subjects. However, there were no differences either in reactive or proactive inhibition between LPD and RPD patients. All in all, these data support the idea that brain regions affected by PD play a fundamental role in subserving inhibitory function, but do not sustain the hypothesis according to which this executive function is predominantly or solely computed by the brain regions of the right hemisphere. Copyright © 2017 Elsevier Ltd. All rights reserved.

Minimal Poems Written in 1979 Minimal Poems Written in 1979

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Sandra Sirangelo Maggio

2008-04-01

Full Text Available The reading of M. van der Slice's Minimal Poems Written in 1979 (the work, actually, has no title reminded me of a book I have seen a long time ago. called Truth, which had not even a single word printed inside. In either case we have a sample of how often excentricities can prove efficient means of artistic creativity, in this new literary trend known as Minimalism. The reading of M. van der Slice's Minimal Poems Written in 1979 (the work, actually, has no title reminded me of a book I have seen a long time ago. called Truth, which had not even a single word printed inside. In either case we have a sample of how often excentricities can prove efficient means of artistic creativity, in this new literary trend known as Minimalism.

Dynamics of excitatory and inhibitory networks are differentially altered by selective attention

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Snyder, Adam C.; Morais, Michael J.

2016-01-01

Inhibition and excitation form two fundamental modes of neuronal interaction, yet we understand relatively little about their distinct roles in service of perceptual and cognitive processes. We developed a multidimensional waveform analysis to identify fast-spiking (putative inhibitory) and regular-spiking (putative excitatory) neurons in vivo and used this method to analyze how attention affects these two cell classes in visual area V4 of the extrastriate cortex of rhesus macaques. We found that putative inhibitory neurons had both greater increases in firing rate and decreases in correlated variability with attention compared with putative excitatory neurons. Moreover, the time course of attention effects for putative inhibitory neurons more closely tracked the temporal statistics of target probability in our task. Finally, the session-to-session variability in a behavioral measure of attention covaried with the magnitude of this effect. Together, these results suggest that selective targeting of inhibitory neurons and networks is a critical mechanism for attentional modulation. PMID:27466133

Dynamics of excitatory and inhibitory networks are differentially altered by selective attention.

Science.gov (United States)

Snyder, Adam C; Morais, Michael J; Smith, Matthew A

2016-10-01

Inhibition and excitation form two fundamental modes of neuronal interaction, yet we understand relatively little about their distinct roles in service of perceptual and cognitive processes. We developed a multidimensional waveform analysis to identify fast-spiking (putative inhibitory) and regular-spiking (putative excitatory) neurons in vivo and used this method to analyze how attention affects these two cell classes in visual area V4 of the extrastriate cortex of rhesus macaques. We found that putative inhibitory neurons had both greater increases in firing rate and decreases in correlated variability with attention compared with putative excitatory neurons. Moreover, the time course of attention effects for putative inhibitory neurons more closely tracked the temporal statistics of target probability in our task. Finally, the session-to-session variability in a behavioral measure of attention covaried with the magnitude of this effect. Together, these results suggest that selective targeting of inhibitory neurons and networks is a critical mechanism for attentional modulation. Copyright © 2016 the American Physiological Society.

Fear extinction causes target-specific remodeling of perisomatic inhibitory synapses

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Trouche, Stéphanie; Sasaki, Jennifer M.; Tu, Tiffany; Reijmers, Leon G.

2013-01-01

SUMMARY A more complete understanding of how fear extinction alters neuronal activity and connectivity within fear circuits may aid in the development of strategies to treat human fear disorders. Using a c-fos based transgenic mouse, we found that contextual fear extinction silenced basal amygdala (BA) excitatory neurons that had been previously activated during fear conditioning. We hypothesized that the silencing of BA fear neurons was caused by an action of extinction on BA inhibitory synapses. In support of this hypothesis, we found extinction-induced target-specific remodeling of BA perisomatic inhibitory synapses originating from parvalbumin and cholecystokinin-positive interneurons. Interestingly, the predicted changes in the balance of perisomatic inhibition matched the silent and active states of the target BA fear neurons. These observations suggest that target-specific changes in perisomatic inhibitory synapses represent a mechanism through which experience can sculpt the activation patterns within a neural circuit. PMID:24183705

Inhibitory effects of Bacillus subtilis on plant pathogens of conservatory in high latitudes

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Xue, Chun-Mei; Wang, Xue; Yang, Jia-Li; Zhang, Yue-Hua

2018-03-01

Researching the effect of three kinds of Bacillus and their mixed strains inhibitory on common fungal diseases of conservatory vegetables. The results showed that B. megaterium culture medium had a significant inhibition effect on Cucumber Fusarium wilt, and the inhibition rate was up to 84.36%; B. mucilaginosus and B. megaterium sterile superna-tant had an obvious inhibitory effect on brown disease of eggplant, and the inhibition rate as high as 85.49%; B. subtilis sterile supernatant had a good inhibitory effect on the spore germination of C. Fusarium wilt, and the inhibition rate was 76.83%. The results revealed that Bacillus had a significant inhibitory effect on five common fungal pathogens. Three kinds of Bacillus can be used for the prevention and control of common fungal diseases in conservatory vegetables.

Investigation on antibacterial synergism of Origanum vulgare and Thymus vulgaris essential oils

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Stojković D.

2013-01-01

Full Text Available Essential oils are well known as strong antimicrobial agents of plant origin. In spite of this, the antimicrobial synergism of essential oils isolated from different plant species is poorly investigated. The following study examines the synergism of the essential oils of Origanum vulgare L. and Thymus vulgaris L against pathogenic bacteria, Staphylococcus aureus and Salmonella typhimurium. First, the antibacterial effect of the oils was tested, and the minimal inhibitory concentrations (MIC of both oils were determined using the microdilution method. To test whether the oils act synergistically, every possible combination of essential oil concentrations was used in a dynamic checkerboard method. The results indicated that the oils indeed acted synergistically with fractional inhibitory concentration indexes of 0.45 and 0.50. [Projekat Ministarstva nauke Republike Srbije, br. 173032

Correlates of minimal dating.

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Leck, Kira

2006-10-01

Researchers have associated minimal dating with numerous factors. The present author tested shyness, introversion, physical attractiveness, performance evaluation, anxiety, social skill, social self-esteem, and loneliness to determine the nature of their relationships with 2 measures of self-reported minimal dating in a sample of 175 college students. For women, shyness, introversion, physical attractiveness, self-rated anxiety, social self-esteem, and loneliness correlated with 1 or both measures of minimal dating. For men, physical attractiveness, observer-rated social skill, social self-esteem, and loneliness correlated with 1 or both measures of minimal dating. The patterns of relationships were not identical for the 2 indicators of minimal dating, indicating the possibility that minimal dating is not a single construct as researchers previously believed. The present author discussed implications and suggestions for future researchers.

Macrophage migration inhibitory factor is associated with aneurysmal expansion

DEFF Research Database (Denmark)

Pan, Jie-Hong; Lindholt, Jes Sanddal; Sukhova, Galina K

2003-01-01

Macrophage migration inhibitory factor (MIF) is an inflammatory cytokine released mainly from macrophages and activated lymphocytes. Both atherosclerosis and abdominal aortic aneurysm (AAA) are inflammatory diseases tightly linked to the function of these cells. The correlation and contribution o...... of MIF to these human diseases remain unknown, although a recent rabbit study showed expression of this cytokine in atherosclerotic lesions.......Macrophage migration inhibitory factor (MIF) is an inflammatory cytokine released mainly from macrophages and activated lymphocytes. Both atherosclerosis and abdominal aortic aneurysm (AAA) are inflammatory diseases tightly linked to the function of these cells. The correlation and contribution...

Fermentation of purple Jerusalem artichoke extract to improve the α-glucosidase inhibitory effect in vitro and ameliorate blood glucose in db/db mice.

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Wang, Zhiqiang; Hwang, Seung Hwan; Lee, Sun Youb; Lim, Soon Sung

2016-06-01

Jerusalem artichoke has inhibitory activity against α-glucosidase and decreases fasting serum glucose levels, which may be related to its fructan content. The biological activity of fructan can be influenced by the degree of polymerization. Thus, in this study, the inhibitory effects of original and fermented purple Jerusalem artichoke (PJA) on α-glucosidase were compared in vitro. Additionally, the anti-diabetes effect of Lactobacillus plantarum-fermented PJA (LJA) was studied in a non-insulin-dependent diabetes mellitus animal model (C57BIKsJ db/db). The water extract of PJA was fermented by L. plantarum, and two strains of Bacillus subtilis to compare their anti-α-glucosidase activities in vitro by α-glucosidase assays. The anti-diabetes effect of LJA was studied in a non-insulin-dependent diabetes mellitus animal model (C57BIKsJ db/db) for seven weeks. During the experiment, food intake, body weight, and fasting blood glucose were measured every week. At the end of the treatment period, several diabetic parameters and the intestinal α-glucosidase activity were measured. The LJA showed the highest α-glucosidase inhibitory activity in vitro. In the in vivo study, it resulted in a significantly lower blood glucose concentration than the control. Serum insulin and HDL cholesterol levels were significantly higher and the concentrations of triglycerides, non-esterified fatty acids, and total cholesterol were significant lower in mice treated with LJA after seven weeks. In addition, the intestinal α-glucosidase activity was partially inhibited. These results suggested that LJA regulates blood glucose and has potential use as a dietary supplement.

Antioxidant and protease-inhibitory potential of extracts from grains of oat

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Krošlák Erik

2016-01-01

Full Text Available The most of important crops cultivated for production of foods and feeds could be considered as plants possessing nutraceutical or medically interesting compounds, especially if can be eaten without processing. Chemical and biological parameters that were evaluated in 100 oat (Avena sativa L. genotypes were others than those that are important in food and feed production. Contents of polyphenols and flavonoids, radical scavenging activity (DPPH, and inhibitory activities against five proteases (trypsin, thrombin, urokinase, elastase, cathepsin B were analyzed in extracts from mature grains. The antioxidant activity (DPPH correlated to the content of total polyphenols. Only a minority (15 from 100 of analyzed genotypes created separate subgroup with a high content of polyphenols, flavonoids, and high antioxidant activity. The best in these parameters were genotypes CDC-SOL-FI, Saul, and Avesta, respectively. Fifteen other genotypes assembled another minority subgroup (also 15 from 100 on the basis of their high inhibitory activities against tested proteases. The highest trypsin-, urokinase-, and elastase-inhibitory activities were in genotype Racoon, the best in thrombin-, and cathepsin B-inhibitory activities were genotypes Expression and SW Kerstin, respectively. Three oats genotypes – Rhea, AC Percy, and Detvan appeared in both subgroups.

Alpha-glucosidase inhibitory and antiplasmodial properties of terpenoids from the leaves of Buddleja saligna Willd.

Science.gov (United States)

Chukwujekwu, Jude C; Rengasamy, Kannan R R; de Kock, Carmen A; Smith, Peter J; Slavětínská, Lenka Poštová; van Staden, Johannes

2016-01-01

In our continuing search for biologically active natural product(s) of plant origin, Buddleja saligna, a South African medicinal plant, was screened in line with its traditional use for antidiabetic (yeast alpha glucosidase inhibitory) and antiplasmodial (against a chloroquine sensitive strain of Plasmodium falciparum (NF54)) activities. The hexane fraction showed the most promising activity with regards to its antidiabetic (IC(50) = 260 ± 0.112 µg/ml) and antiplasmodial (IC(50) = 8.5 ± 1.6 µg/ml) activities. Using activity guided fractionation three known terpenoids (betulonic acid, betulone and spinasterol) were isolated from this species for the first time. The compounds displayed varying levels of biological activities (antidiabetic: 27.31 µg/ml ≥ IC(50) ≥ 5.6 µg/ml; antiplasmodial: 14 µg/ml ≥ IC(50) ≥ 2 µg/ml) with very minimal toxicity.

Brain ageing changes proteoglycan sulfation, rendering perineuronal nets more inhibitory.

Science.gov (United States)

Foscarin, Simona; Raha-Chowdhury, Ruma; Fawcett, James W; Kwok, Jessica C F

2017-06-28

Chondroitin sulfate (CS) proteoglycans in perineuronal nets (PNNs) from the central nervous system (CNS) are involved in the control of plasticity and memory. Removing PNNs reactivates plasticity and restores memory in models of Alzheimer's disease and ageing. Their actions depend on the glycosaminoglycan (GAG) chains of CS proteoglycans, which are mainly sulfated in the 4 (C4S) or 6 (C6S) positions. While C4S is inhibitory, C6S is more permissive to axon growth, regeneration and plasticity. C6S decreases during critical period closure. We asked whether there is a late change in CS-GAG sulfation associated with memory loss in aged rats. Immunohistochemistry revealed a progressive increase in C4S and decrease in C6S from 3 to 18 months. GAGs extracted from brain PNNs showed a large reduction in C6S at 12 and 18 months, increasing the C4S/C6S ratio. There was no significant change in mRNA levels of the chondroitin sulfotransferases. PNN GAGs were more inhibitory to axon growth than those from the diffuse extracellular matrix. The 18-month PNN GAGs were more inhibitory than 3-month PNN GAGs. We suggest that the change in PNN GAG sulfation in aged brains renders the PNNs more inhibitory, which lead to a decrease in plasticity and adversely affect memory.

Minimal Super Technicolor

DEFF Research Database (Denmark)

Antola, M.; Di Chiara, S.; Sannino, F.

2011-01-01

We introduce novel extensions of the Standard Model featuring a supersymmetric technicolor sector (supertechnicolor). As the first minimal conformal supertechnicolor model we consider N=4 Super Yang-Mills which breaks to N=1 via the electroweak interactions. This is a well defined, economical......, between unparticle physics and Minimal Walking Technicolor. We consider also other N =1 extensions of the Minimal Walking Technicolor model. The new models allow all the standard model matter fields to acquire a mass....

Patterned sensory nerve stimulation enhances the reactivity of spinal Ia inhibitory interneurons.

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Kubota, Shinji; Hirano, Masato; Morishita, Takuya; Uehara, Kazumasa; Funase, Kozo

2015-03-25

Patterned sensory nerve stimulation has been shown to induce plastic changes in the reciprocal Ia inhibitory circuit. However, the mechanisms underlying these changes have not yet been elucidated in detail. The aim of the present study was to determine whether the reactivity of Ia inhibitory interneurons could be altered by patterned sensory nerve stimulation. The degree of reciprocal Ia inhibition, the conditioning effects of transcranial magnetic stimulation (TMS) on the soleus (SOL) muscle H-reflex, and the ratio of the maximum H-reflex amplitude versus maximum M-wave (H(max)/M(max)) were examined in 10 healthy individuals. Patterned electrical nerve stimulation was applied to the common peroneal nerve every 1 s (100 Hz-5 train) at the motor threshold intensity of tibialis anterior muscle to induce activity changes in the reciprocal Ia inhibitory circuit. Reciprocal Ia inhibition, the TMS-conditioned H-reflex amplitude, and H(max)/M(max) were recorded before, immediately after, and 15 min after the electrical stimulation. The patterned electrical nerve stimulation significantly increased the degree of reciprocal Ia inhibition and decreased the amplitude of the TMS-conditioned H-reflex in the short-latency inhibition phase, which was presumably mediated by Ia inhibitory interneurons. However, it had no effect on H(max)/M(max). Our results indicated that patterned sensory nerve stimulation could modulate the activity of Ia inhibitory interneurons, and this change may have been caused by the synaptic modification of Ia inhibitory interneuron terminals. These results may lead to a clearer understanding of the spinal cord synaptic plasticity produced by repetitive sensory inputs. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.

The role of cardiac vagal tone and inhibitory control in pre-schoolers' listening comprehension.

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Scrimin, Sara; Patron, Elisabetta; Florit, Elena; Palomba, Daniela; Mason, Lucia

2017-12-01

This study investigated the role of basal cardiac activity and inhibitory control at the beginning of the school year in predicting oral comprehension at the end of the year in pre-schoolers. Forty-three, 4-year-olds participated in the study. At the beginning of the school year children's electrocardiogram at rest was registered followed by the assessment of inhibitory control as well as verbal working memory and verbal ability. At the end of the year all children were administered a listening comprehension ability measure. A stepwise regression showed a significant effect of basal cardiac vagal tone in predicting listening comprehension together with inhibitory control and verbal ability. These results are among the first to show the predictive role of basal cardiac vagal tone and inhibitory control in pre-schoolers' oral text comprehension, and offer new insight into the association between autonomic regulation of the heart, inhibitory control, and cognitive activity at a young age. © 2017 Wiley Periodicals, Inc.

Critical analysis of the maximum non inhibitory concentration (MNIC) method in quantifying sub-lethal injury in Saccharomyces cerevisiae cells exposed to either thermal or pulsed electric field treatments.

Science.gov (United States)

Kethireddy, V; Oey, I; Jowett, Tim; Bremer, P

2016-09-16

Sub-lethal injury within a microbial population, due to processing treatments or environmental stress, is often assessed as the difference in the number of cells recovered on non-selective media compared to numbers recovered on a "selective media" containing a predetermined maximum non-inhibitory concentration (MNIC) of a selective agent. However, as knowledge of cell metabolic response to injury, population diversity and dynamics increased, the rationale behind the conventional approach of quantifying sub-lethal injury must be scrutinized further. This study reassessed the methodology used to quantify sub-lethal injury for Saccharomyces cerevisiae cells (≈ 4.75 Log CFU/mL) exposed to either a mild thermal (45°C for 0, 10 and 20min) or a mild pulsed electric field treatment (field strengths of 8.0-9.0kV/cm and energy levels of 8, 14 and 21kJ/kg). Treated cells were plated onto either Yeast Malt agar (YM) or YM containing NaCl, as a selective agent at 5-15% in 1% increments. The impact of sub-lethal stress due to initial processing, the stress due to selective agents in the plating media, and the subsequent variation of inhibition following the treatments was assessed based on the CFU count (cell numbers). ANOVA and a generalised least squares model indicated significant effects of media, treatments, and their interaction effects (P<0.05) on cell numbers. It was shown that the concentration of the selective agent used dictated the extent of sub-lethal injury recorded owing to the interaction effects of the selective component (NaCl) in the recovery media. Our findings highlight a potential common misunderstanding on how culture conditions impact on sub-lethal injury. Interestingly for S. cerevisiae cells the number of cells recovered at different NaCl concentrations in the media appears to provide valuable information about the mode of injury, the comparative efficacy of different processing regimes and the inherent degree of resistance within a population. This

Inhibitory activity of Iranian plant extracts on growth and biofilm formation by Pseudomonas aeruginosa

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Mansouri, S.

2013-01-01

Full Text Available Aims: Pseudomonas aeruginosa is a drug resistance opportunistic bacterium. Biofilm formation is key factor for survivalof P. aeruginosa in various environments. Polysaccharides may be involved in biofilm formation. The purpose of thisstudy was to evaluate antimicrobial and anti-biofilm activities of seven plant extracts with known alpha-glucosidaseinhibitory activities on different strains of P. aeruginosa.Methodology and results: Plants were extracted with methanol by the maceration method. Antimicrobial activities weredetermined by agar dilution and by growth yield as measured by OD560nm of the Luria Bertani broth (LB culture with orwithout extracts. In agar dilution method, extracts of Quercus infectoria inhibited the growth of all, while Myrtuscommunis extract inhibited the growth of 3 out of 8 bacterial strains with minimum inhibitory concentration (MIC of 1000μg/mL. All extracts significantly (p≤0.003 reduced growth rate of the bacteria in comparison with the control withoutextracts in LB broth at sub-MIC concentrations (500 μg/mL. All plant extracts significantly (p≤0.003 reduced biofilmformation compared to the controls. Glycyrrhiza glabra and Q. infectoria had the highest anti-biofilm activities. Nocorrelation between the alpha-glucosidase inhibitory activity with growth or the intensity of biofilm formation was found.Conclusion, significance and impact of study: Extracts of Q. infectoria and M. communis had the most antimicrobial,while Q. infectoria and G. glabra had the highest anti-biofilm activities. All plant extracts had anti-biofilm activities withmarginal effect on growth, suggesting that the mechanisms of these activities are unrelated to static or cidal effects.Further work to understand the relation between antimicrobial and biofilm formation is needed for development of newmeans to fight the infectious caused by this bacterium in future.

Antioxidant and ACE Inhibitory Bioactive Peptides Purified from Egg Yolk Proteins

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Marwa Yousr

2015-12-01

Full Text Available Protein by-products from the extraction of lecithin from egg yolk can be converted into value-added products, such as bioactive hydrolysates and peptides that have potential health enhancing antioxidant, and antihypertensive properties. In this study, the antioxidant and angiotensin converting enzyme (ACE inhibitory activities of peptides isolated and purified from egg yolk protein were investigated. Defatted egg yolk was hydrolyzed using pepsin and pancreatin and sequentially fractionated by ultrafiltration, followed by gel filtration to produce egg yolk gel filtration fractions (EYGF. Of these, two fractions, EYGF-23 and EYGF-33, effectively inhibited the peroxides and thiobarbituric acid reactive substance (TBARS in an oxidizing linoleic acid model system. The antioxidant mechanism involved superoxide anion and hydroxyl radicals scavenging and ferrous chelation. The presence of hydrophobic amino acids such as tyrosine (Y and tryptophan (W, in sequences identified by LC-MS as WYGPD (EYGF-23 and KLSDW (EYGF-33, contributed to the antioxidant activity and were not significantly different from the synthetic BHA antioxidant. A third fraction (EYGF-56 was also purified from egg yolk protein by gel filtration and exhibited high ACE inhibitory activity (69% and IC50 value (3.35 mg/mL. The SDNRNQGY peptide (10 mg/mL had ACE inhibitory activity, which was not significantly different from that of the positive control captopril (0.5 mg/mL. In addition, YPSPV in (EYGF-33 (10 mg/mL had higher ACE inhibitory activity compared with captopril. These findings indicated a substantial potential for producing valuable peptides with antioxidant and ACE inhibitory activity from egg yolk.

Antioxidant and ACE Inhibitory Bioactive Peptides Purified from Egg Yolk Proteins.

Science.gov (United States)

Yousr, Marwa; Howell, Nazlin

2015-12-07

Protein by-products from the extraction of lecithin from egg yolk can be converted into value-added products, such as bioactive hydrolysates and peptides that have potential health enhancing antioxidant, and antihypertensive properties. In this study, the antioxidant and angiotensin converting enzyme (ACE) inhibitory activities of peptides isolated and purified from egg yolk protein were investigated. Defatted egg yolk was hydrolyzed using pepsin and pancreatin and sequentially fractionated by ultrafiltration, followed by gel filtration to produce egg yolk gel filtration fractions (EYGF). Of these, two fractions, EYGF-23 and EYGF-33, effectively inhibited the peroxides and thiobarbituric acid reactive substance (TBARS) in an oxidizing linoleic acid model system. The antioxidant mechanism involved superoxide anion and hydroxyl radicals scavenging and ferrous chelation. The presence of hydrophobic amino acids such as tyrosine (Y) and tryptophan (W), in sequences identified by LC-MS as WYGPD (EYGF-23) and KLSDW (EYGF-33), contributed to the antioxidant activity and were not significantly different from the synthetic BHA antioxidant. A third fraction (EYGF-56) was also purified from egg yolk protein by gel filtration and exhibited high ACE inhibitory activity (69%) and IC50 value (3.35 mg/mL). The SDNRNQGY peptide (10 mg/mL) had ACE inhibitory activity, which was not significantly different from that of the positive control captopril (0.5 mg/mL). In addition, YPSPV in (EYGF-33) (10 mg/mL) had higher ACE inhibitory activity compared with captopril. These findings indicated a substantial potential for producing valuable peptides with antioxidant and ACE inhibitory activity from egg yolk.

New polyacetylenes glycoside from Eclipta prostrate with DGAT inhibitory activity.

Science.gov (United States)

Meng, Xiao; Li, Ban-Ban; Lin, Xin; Jiang, Yi-Yu; Zhang, Le; Li, Hao-Ze; Cui, Long

2018-06-08

One new polyacetylene glycoside eprostrata Ⅰ (1), together with seven known compounds (2-8), were isolated from Eclipta prostrata. Their structures were elucidated on the basis of spectroscopic and physico-chemical analyses. All the isolates were evaluated inhibitory activity on DGAT in an in vitro assay. Compounds 1-8 were found to exhibit inhibitory activity of DGAT1 with IC 50 values ranging from 74.4 ± 1.3 to 101.1 ± 1.1 μM.

Limit behavior of mass critical Hartree minimization problems with steep potential wells

Science.gov (United States)

Guo, Yujin; Luo, Yong; Wang, Zhi-Qiang

2018-06-01

We consider minimizers of the following mass critical Hartree minimization problem: eλ(N ) ≔inf {u ∈H1(Rd ) , ‖u‖2 2=N } Eλ(u ) , where d ≥ 3, λ > 0, and the Hartree energy functional Eλ(u) is defined by Eλ(u ) ≔∫Rd|∇u (x ) |2d x +λ ∫Rdg (x ) u2(x ) d x -1/2 ∫Rd∫Rdu/2(x ) u2(y ) |x -y |2 d x d y . Here the steep potential g(x) satisfies 0 =g (0 ) =infRdg (x ) ≤g (x ) ≤1 and 1 -g (x ) ∈Ld/2(Rd ) . We prove that there exists a constant N* > 0, independent of λg(x), such that if N ≥ N*, then eλ(N) does not admit minimizers for any λ > 0; if 0 N N*, then there exists a constant λ*(N) > 0 such that eλ(N) admits minimizers for any λ > λ*(N) and eλ(N) does not admit minimizers for 0 N). For any given 0 N N*, the limit behavior of positive minimizers for eλ(N) is also studied as λ → ∞, where the mass concentrates at the bottom of g(x).

Inhibitory control and negative emotional processing in psychopathy and antisocial personality disorder.

Science.gov (United States)

Verona, Edelyn; Sprague, Jenessa; Sadeh, Naomi

2012-05-01

The field of personality disorders has had a long-standing interest in understanding interactions between emotion and inhibitory control, as well as neurophysiological indices of these processes. More work in particular is needed to clarify differential deficits in offenders with antisocial personality disorder (APD) who differ on psychopathic traits, as APD and psychopathy are considered separate, albeit related, syndromes. Evidence of distinct neurobiological processing in these disorders would have implications for etiology-based personality disorder taxonomies in future psychiatric classification systems. To inform this area of research, we recorded event-related brain potentials during an emotional-linguistic Go/No-Go task to examine modulation of negative emotional processing by inhibitory control in three groups: psychopathy (n = 14), APD (n = 16), and control (n = 15). In control offenders, inhibitory control demands (No-Go vs. Go) modulated frontal-P3 amplitude to negative emotional words, indicating appropriate prioritization of inhibition over emotional processing. In contrast, the psychopathic group showed blunted processing of negative emotional words regardless of inhibitory control demands, consistent with research on emotional deficits in psychopathy. Finally, the APD group demonstrated enhanced processing of negative emotion words in both Go and No-Go trials, suggesting a failure to modulate negative emotional processing when inhibitory control is required. Implications for emotion-cognition interactions and putative etiological processes in these personality disorders are discussed.

Fear extinction causes target-specific remodeling of perisomatic inhibitory synapses.

Science.gov (United States)

Trouche, Stéphanie; Sasaki, Jennifer M; Tu, Tiffany; Reijmers, Leon G

2013-11-20

A more complete understanding of how fear extinction alters neuronal activity and connectivity within fear circuits may aid in the development of strategies to treat human fear disorders. Using a c-fos-based transgenic mouse, we found that contextual fear extinction silenced basal amygdala (BA) excitatory neurons that had been previously activated during fear conditioning. We hypothesized that the silencing of BA fear neurons was caused by an action of extinction on BA inhibitory synapses. In support of this hypothesis, we found extinction-induced target-specific remodeling of BA perisomatic inhibitory synapses originating from parvalbumin and cholecystokinin-positive interneurons. Interestingly, the predicted changes in the balance of perisomatic inhibition matched the silent and active states of the target BA fear neurons. These observations suggest that target-specific changes in perisomatic inhibitory synapses represent a mechanism through which experience can sculpt the activation patterns within a neural circuit. Copyright © 2013 Elsevier Inc. All rights reserved.

Acetylcholinesterase inhibitory effects of some plants from Rosaceae

Directory of Open Access Journals (Sweden)

S. Esmaeili

2015-10-01

Full Text Available Background and objectives: Alzheimer's disease (AD is an age dependent disorder. AD is associated with decrease of brain acetylcholine level. Nowadays, one of the methods for progression inhibition of AD is using acetylcholinesterase inhibitors. Rosaceae is a large plant family. Different biological effects of some species of this family have been reported. The aim of the present study was to assess the acetylcholinesterase inhibitory (AChEI activity of the selected plants belonging to Rosaceae family. Methods: AChEI activity of six species from Rosaceae including Cotoneaster nummularia, Cerasus microcarpa, Amygdalus scoparia, Agrimonia eupatoria, Rosa canina and Rosa damascena were evaluated based on Ellman’s method in concentration of 300 µg/mL using total extracts and methanol fractions which were obtained by maceration. Results: The results showed that the total extract and methanol fraction of the aerial parts of A. eupatoria demonstrated significant AChEI activity with 46.5% and 56.2% inhibition of the enzyme, respectively. Conclusion: According to the results of the AChEI activity of the methanol fraction of A. eupatoria, it seems that the polar components of the species such as flavonoids may be responsible for its effectiveness.

An investigation of vancomycin minimum inhibitory concentration creep among methicillin-resistant Staphylococcus aureus strains isolated from pediatric patients and healthy children in Northern Taiwan.

Science.gov (United States)

Chang, Chia-Ning; Lo, Wen-Tsung; Chan, Ming-Chin; Yu, Ching-Mei; Wang, Chih-Chien

2017-06-01

The phenomenon of vancomycin minimum inhibitory concentration (MIC) creep is an increasingly serious problem in the treatment of methicillin-resistant Staphylococcus aureus (MRSA) infections. In this study, we investigated the vancomycin and daptomycin MIC values of MRSA strains isolated from pediatric patients and MRSA colonized healthy children. Then, we assessed whether there was evidence of clonal dissemination for strains with an MIC to vancomycin of ≥ 1.5 μg/mL. We collected clinical MRSA isolates from pediatric patients and from healthy children colonized with MRSA during 2008-2012 at a tertiary medical center in northern Taiwan and obtained vancomycin and daptomycin MIC values using the Etest method. Pulse-field gel electrophoresis (PFGE) and staphylococcal cassette chromosome (SCCmec) typing were used to assess clonal dissemination for strains with an MIC to vancomycin of ≥ 1.5 μg/mL. A total 195 MRSA strains were included in this study; 87 were isolated patients with a clinical MRSA infection, and the other 108 strains from nasally colonized healthy children. Vancomycin MIC≥1.5 μg/mL was seen in more clinical isolates (60/87, 69%) than colonized isolates (32/108, 29.6%), p < 0.001. The PFGE typing of both strains revealed multiple pulsotypes. Vancomycin MIC creeps existed in both clinical MRSA isolates and colonized MRSA strains. Great diversity of PFGE typing was in both strains collected. There was no association between the clinical and colonized MRSA isolates with vancomycin MIC creep. Copyright © 2016. Published by Elsevier B.V.

[Preoperatively administered flomoxef sodium concentration in aqueous humor].

Science.gov (United States)

Miyamoto, Mariko; Watanabe, Yoichiro; Mizuki, Nobuhisa

2007-04-01

We intravenously administered flomoxef sodium (FMOX) 0.5-3.5 hours before cataract surgery and measured the concentration of the agent in the aqueous humor to investigate its penetration into the aqueous humor and its efficacy in the prevention of postoperative endophthalmitis. 56 patients who underwent cataract surgery were enrolled in this study. They received 1 g FMOX via a 20-minute intravenous drip beginning 0.5-3.5 hours before the operation. Aqueous humor was aspirated from the anterior chamber and assayed for FMOX concentration using high-performance liquid chromatography. The mean intraoperative FMOX concentrations in the patients' aqueous humor were 0.79 +/- 0.24 microg/ml (administered 3.5 hours before surgery)--1.47 0.79 microg/ml (administered 1.5 hours before surgery). These concentrations administered 0.5-3.0 hours before surgery sufficiently exceeded the minimum inhibitory concentration (MIC) 90 values against Staphylococcus epidermidis, Staphylococcus aureus and Propionibacterium acnes, but did not achieve the MIC90 values against Enterococcus faecalis and Pseudomonas aeruginosa. The FMOX concentrations in the aqueous humor sampling were adequate to kill bacteria in vitro. This drug may be efficacious in the prevention of postoperative endophthalmitis in patients undergoing cataract surgery.

Penicillin tolerance among Beta-hemolytic streptococci and production of the group carbohydrates, hemolysins, hyaluronidases and deoxyribonucleases

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Cássia C. Avelino

1995-08-01

Full Text Available Penicillin tolerance among 67 strains of beta-hemolytic streptococci was examined by determining the ratio of the minimal bactericidal concentration to the minimal inhibitory concentration as 32 or greater. Tolerance was demonstrated in 15 group A strains and in 11,7, and 4 of groups B, C and G, respectively. Thereafter the effects of a subminimal inhibitory concentration (1/2MIC of penicillin on the bacterial products of four tolerant and four nontolerant strains (two of each Lancefield group were analyzed and compared. The antibiotic caused a marked increase in the expression of the group carbo-hydrates for strains of group B. Penicillin was found to reduce the cell-bound hemolysin activities of the four tolerant strains and to increase the activity of the other (free form of nontolerant groups A, C and G hemolysins. Penicillin caused an increase in the extracellular hyaluronidase activities of one group A and groups B, C and G streptococci. With added antibiotic the production of deoxyribonuclease by tolerant groups A, C and G was greatly enhanced and that of the group B streptococcus was arrested.

Raltegravir cerebrospinal fluid concentrations in HIV-1 infection.

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Aylin Yilmaz

2009-09-01

Full Text Available Raltegravir is an HIV-1 integrase inhibitor currently used in treatment-experienced HIV-1-infected patients resistant to other drug classes. In order to assess its central nervous system penetration, we measured raltegravir concentrations in cerebrospinal fluid (CSF and plasma in subjects receiving antiretroviral treatment regimens containing this drug.Raltegravir concentrations were determined by liquid chromatography tandem mass spectrometry in 25 paired CSF and plasma samples from 16 HIV-1-infected individuals. The lower limit of quantitation was 2.0 ng/ml for CSF and 10 ng/ml for plasma.Twenty-four of the 25 CSF samples had detectable raltegravir concentrations with a median raltegravir concentration of 18.4 ng/ml (range, <2.0-126.0. The median plasma raltegravir concentration was 448 ng/ml (range, 37-5180. CSF raltegravir concentrations correlated with CSF:plasma albumin ratios and CSF albumin concentrations.Approximately 50% of the CSF specimens exceeded the IC(95 levels reported to inhibit HIV-1 strains without resistance to integrase inhibitors. In addition to contributing to control of systemic HIV-1 infection, raltegravir achieves local inhibitory concentrations in CSF in most, but not all, patients. Blood-brain and blood-CSF barriers likely restrict drug entry, while enhanced permeability of these barriers enhances drug entry.

Raltegravir cerebrospinal fluid concentrations in HIV-1 infection.

Science.gov (United States)

Yilmaz, Aylin; Gisslén, Magnus; Spudich, Serena; Lee, Evelyn; Jayewardene, Anura; Aweeka, Francesca; Price, Richard W

2009-09-01

Raltegravir is an HIV-1 integrase inhibitor currently used in treatment-experienced HIV-1-infected patients resistant to other drug classes. In order to assess its central nervous system penetration, we measured raltegravir concentrations in cerebrospinal fluid (CSF) and plasma in subjects receiving antiretroviral treatment regimens containing this drug. Raltegravir concentrations were determined by liquid chromatography tandem mass spectrometry in 25 paired CSF and plasma samples from 16 HIV-1-infected individuals. The lower limit of quantitation was 2.0 ng/ml for CSF and 10 ng/ml for plasma. Twenty-four of the 25 CSF samples had detectable raltegravir concentrations with a median raltegravir concentration of 18.4 ng/ml (range, <2.0-126.0). The median plasma raltegravir concentration was 448 ng/ml (range, 37-5180). CSF raltegravir concentrations correlated with CSF:plasma albumin ratios and CSF albumin concentrations. Approximately 50% of the CSF specimens exceeded the IC(95) levels reported to inhibit HIV-1 strains without resistance to integrase inhibitors. In addition to contributing to control of systemic HIV-1 infection, raltegravir achieves local inhibitory concentrations in CSF in most, but not all, patients. Blood-brain and blood-CSF barriers likely restrict drug entry, while enhanced permeability of these barriers enhances drug entry.

Panel Flutter Emulation Using a Few Concentrated Forces

Science.gov (United States)

Dhital, Kailash; Han, Jae-Hung

2018-04-01

The objective of this paper is to study the feasibility of panel flutter emulation using a few concentrated forces. The concentrated forces are considered to be equivalent to aerodynamic forces. The equivalence is carried out using surface spline method and principle of virtual work. The structural modeling of the plate is based on the classical plate theory and the aerodynamic modeling is based on the piston theory. The present approach differs from the linear panel flutter analysis in scheming the modal aerodynamics forces with unchanged structural properties. The solutions for the flutter problem are obtained numerically using the standard eigenvalue procedure. A few concentrated forces were considered with an optimization effort to decide their optimal locations. The optimization process is based on minimizing the error between the flutter bounds from emulated and linear flutter analysis method. The emulated flutter results for the square plate of four different boundary conditions using six concentrated forces are obtained with minimal error to the reference value. The results demonstrated the workability and viability of using concentrated forces in emulating real panel flutter. In addition, the paper includes the parametric studies of linear panel flutter whose proper literatures are not available.

Families of bitangent planes of space curves and minimal non-fibration families

KAUST Repository

Lubbes, Niels

2014-01-01

A cone curve is a reduced sextic space curve which lies on a quadric cone and does not pass through the vertex. We classify families of bitangent planes of cone curves. The methods we apply can be used for any space curve with ADE singularities, though in this paper we concentrate on cone curves. An embedded complex projective surface which is adjoint to a degree one weak Del Pezzo surface contains families of minimal degree rational curves, which cannot be defined by the fibers of a map. Such families are called minimal non-fibration families. Families of bitangent planes of cone curves correspond to minimal non-fibration families. The main motivation of this paper is to classify minimal non-fibration families. We present algorithms which compute all bitangent families of a given cone curve and their geometric genus. We consider cone curves to be equivalent if they have the same singularity configuration. For each equivalence class of cone curves we determine the possible number of bitangent families and the number of rational bitangent families. Finally we compute an example of a minimal non-fibration family on an embedded weak degree one Del Pezzo surface.

On relevant boundary perturbations of unitary minimal models

International Nuclear Information System (INIS)

Recknagel, A.; Roggenkamp, D.; Schomerus, V.

2000-01-01

We consider unitary Virasoro minimal models on the disk with Cardy boundary conditions and discuss deformations by certain relevant boundary operators, analogous to tachyon condensation in string theory. Concentrating on the least relevant boundary field, we can perform a perturbative analysis of renormalization group fixed points. We find that the systems always flow towards stable fixed points which admit no further (non-trivial) relevant perturbations. The new conformal boundary conditions are in general given by superpositions of 'pure' Cardy boundary conditions

Plants from Brazilian Cerrado with potent tyrosinase inhibitory activity.

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Paula Monteiro Souza

Full Text Available The increased amount of melanin leads to skin disorders such as age spots, freckles, melasma and malignant melanoma. Tyrosinase is known to be the key enzyme in melanin production. Plants and their extracts are inexpensive and rich resources of active compounds that can be utilized to inhibit tyrosinase as well as can be used for the treatment of dermatological disorders associated with melanin hyperpigmentation. Using in vitro tyrosinase inhibitory activity assay, extracts from 13 plant species from Brazilian Cerrado were evaluated. The results showed that Pouteria torta and Eugenia dysenterica extracts presented potent in vitro tyrosinase inhibition compared to positive control kojic acid. Ethanol extract of Eugenia dysenterica leaves showed significant (p<0.05 tyrosinase inhibitory activity exhibiting the IC₅₀ value of 11.88 µg/mL, compared to kojic acid (IC₅₀ value of 13.14 µg/mL. Pouteria torta aqueous extract leaves also showed significant inhibitory activity with IC₅₀ value of 30.01 µg/mL. These results indicate that Pouteria torta and Eugenia dysenterica extracts and their isolated constituents are promising agents for skin-whitening or antimelanogenesis formulations.

Parameter-free method for the shape optimization of stiffeners on thin-walled structures to minimize stress concentration

Energy Technology Data Exchange (ETDEWEB)

Liu, Yang; Shibutan, Yoji [Osaka University, Osaka (Japan); Shimoda, Masatoshi [Toyota Technological Institute, Nagoya (Japan)

2015-04-15

This paper presents a parameter-free shape optimization method for the strength design of stiffeners on thin-walled structures. The maximum von Mises stress is minimized and subjected to the volume constraint. The optimum design problem is formulated as a distributed-parameter shape optimization problem under the assumptions that a stiffener is varied in the in-plane direction and that the thickness is constant. The issue of nondifferentiability, which is inherent in this min-max problem, is avoided by transforming the local measure to a smooth differentiable integral functional by using the Kreisselmeier-Steinhauser function. The shape gradient functions are derived by using the material derivative method and adjoint variable method and are applied to the H{sup 1} gradient method for shells to determine the optimal free-boundary shapes. By using this method, the smooth optimal stiffener shape can be obtained without any shape design parameterization while minimizing the maximum stress. The validity of this method is verified through two practical design examples.

Pre- and postjunctional inhibitory effects of fenspiride on guinea-pig bronchi.

Science.gov (United States)

Girard, V; Naline, E; Crambes, O; Malbezin, M; Malmström, R E; Lundberg, J M; Advenier, C

1997-05-01

Fenspiride is a drug with potential benefits in the treatment of obstructive airways disease. It has antibronchoconstriction and anti-inflammatory properties. The aim of this study was to investigate the effect of this drug on the contractions induced in the guinea-pig isolated main bronchus and perfused lung by electrical field stimulation (EFS) or exogenously added agents. Bronchi were stimulated transmurally in the presence of indomethacin 10(-6) M and propranolol 10(-6) M, and isometric tension was measured. In the perfused lung model calcitonin gene-related peptide (CGRP) release was determined in the perfusate fractions as a measure of neuropeptide production. Two successive contractile responses were observed: a rapid cholinergic contraction, followed by a long-lasting contraction due to local release of neuropeptides from C-fibre endings. Fenspiride (10(-6) to 10(-4) M) inhibited the nonadrenergic, noncholinergic (NANC) component of the contraction of the guinea-pig isolated main bronchus induced by EFS. Fenspiride significantly affected contractions induced by exogenously added substance P or [Nle10]-NKA(4-10) only at concentrations higher than 10(-3) M. In the guinea-pig perfused lung, fenspiride inhibited low pH- but not capsaicin-evoked release of CGRP. At higher concentrations (10(-4) M to 3x10(-4) M) fenspiride exhibited a significant inhibitory effect both on the cholinergic component of contractile response induced by EFS in the guinea-pig isolated main bronchus and on exogenously added acetylcholine. In conclusion, the result of this study suggests that fenspiride, in moderate concentrations, reduces the release of neuropeptides, including tachykinins, from sensory nerve endings at a prejunctional level. At higher concentrations, postjunctional actions on bronchial smooth muscle are also present.

Inhibitory effect of zinc oxide nanoparticles on pseudomonas aeruginosa biofilm formation

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Mohammad Hassani Sangani

2015-04-01

Full Text Available Objective(s: Bacterial biofilm formation causes many persistent and chronic infections. The matrix protects biofilm bacteria from exposure to innate immune defenses and antibiotic treatments. The purpose of this study was to evaluate the biofilm formation of clinical isolates of Pseudomonas aeruginosa and the activity of zinc oxide nanoparticles (ZnO NPs on biofilm. Materials and Methods: After collecting bacteria from clinical samples of hospitalized patients, the ability of organisms were evaluated to create biofilm by tissue culture plate (TCP assay. ZnO NPs were synthesized by sol gel method and the efficacy of different concentrations (50- 350 µg/ml of ZnO NPs was assessed on biofilm formation and also elimination of pre-formed biofilm by using TCP method. Results:The average diameter of synthesized ZnO NPs was 20 nm. The minimum inhibitory concentration of nanoparticles was 150- 158 μg/ml and the minimum bactericidal concentration was higher (325 µg/ml. All 15 clinical isolates of P. aeruginosa were able to produce biofilm. Treating the organisms with nanoparticles at concentrations of 350 μg/ml resulted in more than 94% inhibition in OD reduction%. Molecular analysis showed that the presence of mRNA of pslA gene after treating bacteria with ZnO NPs for 30 minutes. Conclusion: The results showed that ZnO NPs can inhibit the establishment of P. aeruginosa biofilms and have less effective in removing pre-formed biofilm. However the tested nanoparticles exhibited anti-biofilm effect, but mRNA of pslA gene could be still detected in the medium by RT-PCR technique after 30 minutes treatment with ZnO.

Selective synaptic targeting of the excitatory and inhibitory presynaptic organizers FGF22 and FGF7.

Science.gov (United States)

Terauchi, Akiko; Timmons, Kendall M; Kikuma, Koto; Pechmann, Yvonne; Kneussel, Matthias; Umemori, Hisashi

2015-01-15

Specific formation of excitatory and inhibitory synapses is crucial for proper functioning of the brain. Fibroblast growth factor 22 (FGF22) and FGF7 are postsynaptic-cell-derived presynaptic organizers necessary for excitatory and inhibitory presynaptic differentiation, respectively, in the hippocampus. For the establishment of specific synaptic networks, these FGFs must localize to appropriate synaptic locations - FGF22 to excitatory and FGF7 to inhibitory postsynaptic sites. Here, we show that distinct motor and adaptor proteins contribute to intracellular microtubule transport of FGF22 and FGF7. Excitatory synaptic targeting of FGF22 requires the motor proteins KIF3A and KIF17 and the adaptor protein SAP102 (also known as DLG3). By contrast, inhibitory synaptic targeting of FGF7 requires the motor KIF5 and the adaptor gephyrin. Time-lapse imaging shows that FGF22 moves with SAP102, whereas FGF7 moves with gephyrin. These results reveal the basis of selective targeting of the excitatory and inhibitory presynaptic organizers that supports their different synaptogenic functions. Finally, we found that knockdown of SAP102 or PSD95 (also known as DLG4), which impairs the differentiation of excitatory synapses, alters FGF7 localization, suggesting that signals from excitatory synapses might regulate inhibitory synapse formation by controlling the distribution of the inhibitory presynaptic organizer. © 2015. Published by The Company of Biologists Ltd.

Inhibitory effect of berberine on the invasion of human lung cancer cells via decreased productions of urokinase-plasminogen activator and matrix metalloproteinase-2

International Nuclear Information System (INIS)

Peng, P.-L.; Hsieh, Y.-S.; Wang, C.-J.; Hsu, J.-L.; Chou, F.-P.

2006-01-01

Berberine, a compound isolated from medicinal herbs, has been reported with many pharmacological effects related to anti-cancer and anti-inflammation capabilities. In this study, we observed that berberine exerted a dose- and time-dependent inhibitory effect on the motility and invasion ability of a highly metastatic A549 cells under non-cytotoxic concentrations. In cancer cell migration and invasion process, matrix-degrading proteinases are required. A549 cell treated with berberine at various concentrations showed reduced ECM proteinases including matrix metalloproteinase-2 (MMP2) and urokinase-plasminogen activator (u-PA) by gelatin and casein zymography analysis. The inhibitory effect is likely to be at the transcriptional level, since the reduction in the transcripts levels was corresponding to the proteins. Moreover, berberine also exerted its action via regulating tissue inhibitor of metalloproteinase-2 (TIMP-2) and urokinase-plasminogen activator inhibitor (PAI). The upstream mediators of the effect involved c-jun, c-fos and NF-κB, as evidenced by reduced phosphorylation of the proteins. These findings suggest that berberine possesses an anti-metastatic effect in non-small lung cancer cell and may, therefore, be helpful in clinical treatment

Macrophage migration inhibitory factor and autism spectrum disorders

NARCIS (Netherlands)

Grigorenko, Elena L.; Han, Summer S.; Yrigollen, Carolyn M.; Leng, Lin; Mizue, Yuka; Anderson, George M.; Mulder, Erik J.; de Bildt, Annelies; Minderaa, Ruud B.; Volkmar, Fred R.; Chang, Joseph T.; Bucala, Richard

OBJECTIVE. Autistic spectrum disorders are childhood neurodevelopmental disorders characterized by social and communicative impairment and repetitive and stereotypical behavior. Macrophage migration inhibitory factor (MIF) is an upstream regulator of innate immunity that promotes

Chemical composition of essential oil in Mosla chinensis Maxim cv. Jiangxiangru and its inhibitory effect on Staphylococcus aureus biofilm formation

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Peng Liang

2018-03-01

Full Text Available The essential oil of Mosla chinensis Maxim cv. Jiangxiangru is known for its antibacterial ability. This study aimed to investigate the chemical composition of Jiangxiangru essential oil and its inhibitory effect on Staphylococcus aureus biofilm formation. Gas chromatography/mass spectrometry (GC–MS was used to determine the chemical composition of Jiangxiangru essential oil. Subsequently, the eight major chemical components were quantitatively analyzed using GC– MS, and their minimum inhibitory concentration (MIC values against S. aureus were tested. Biofilm formation was detected by crystal violet semi-quantitative method and silver staining. Of the 59 peaks detected, 29 were identified by GC–MS. Of these peaks, thymol, carvacrol, p-cymene, γ-terpinene, thymol acetate, α-caryophyllene, 3-carene, and carvacryl acetate were present at a relatively higher concentration. The results of the quantitative test showed that thymol, carvacrol, p-cymene, and γ-terpinene were the major components of the essential oil. Among the eight reference substances, only thymol, carvacrol, and thymol acetate had lower MICs compared with the essential oil. Essential oil, carvacrol, carvacryl acetate, α-caryophyllene, and 3-carene showed the better inhibition of S. aureus biofilm formation. When one fourth of the MIC concentrations were used for these substances (0.0625 mg/mL for essential oil, 0.0305 mg/mL for carvacrol, 1.458 mg/mL for carvacryl acetate, 0.1268 mg/mL for α-caryophyllene, and 2.5975 mg/mL for 3-carene, the inhibition rates were over 80%. However, thymol, γ-terpinene, thymol acetate, and p-cymene showed a relatively poor inhibition of S. aureus biofilm formation. When 1× MIC concentrations of these substances were used, the inhibition rates were less than 50%. In conclusion, Jiangxiangru essential oil and its major components, carvacrol, carvacryl acetate, α-caryophyllene, and 3-carene, strongly inhibited biofilm formation in S. aureus.

Micropollutants in closed life-support systems: the case of triclosan, a biocide excreted via urine

Science.gov (United States)

Mastroleo, Felice; Pycke, Benny; Boon, Nico; de Wever, Heleen; Hendrickx, Larissa; Mastroleo, Felice; Wattiez, Ruddy; Mergeay, Max; Verstraete, Willy

OBJECTIVES: The impact of triclosan on the growth and physiology of the bacterium Rhodospirillum rubrum was studied in the frame of the regenerative life-support system, Micro- Ecological Life Support System Alternative (MELiSSA). A wide range of compounds, such as steroid hormones, pharmaceuticals and personal care products, might enter the life support system via the excrements that are to be treated and recycled. Triclosan was chosen as the first compound to be tested because MELiSSA is a closed system, which is consequently particularly sensitive to compounds inhibiting the microbial metabolism. Because triclosan is increasingly used as an antimicrobial biocide in hygienic formulations (such as toothpaste, mouthwash, deodorants, etc.) and due to its chemical stability, it is considered an emerging pollutant in terrestrial ecosystems. METHODS: In a first phase, the triclosan concentration expected in the life-support system was estimated, the Minimal Inhibitory Concentration (MIC) was determined via plating, and the effect on growth kinetics was assessed by comparing growth parameters in the Gompertz model. In a second phase, the secondary effects of triclosan on cell physiology and gene expression were studied through flow-cytometry and microarray analyses, respectively. RESULTS: Based on the pharmacokinetic data from literature, the predicted concentration range is estimated to be 6-25µg/L triclosan in the Rhodospirillum rubrum compartment of the MELiSSA. The minimal inhibitory concentration of triclosan was determined to be 71 µg/L after 7 days of exposure on Sistrom medium. Upon exposure to 50-200µg/L triclosan, triclosan-resistant mutants of Rhodospirillum rubrum arose spontaneously at high frequency (3.1 ∗ 10 - 4). Analysis of the growth kinetics of the wild-type revealed that triclosan causes an important elongation of the lag-phase and a decrease in growth rate. At concentrations higher than 75mg/L(LD = 500mg/L), triclosan is bactericidal to wild

Graphene oxide significantly inhibits cell growth at sublethal concentrations by causing extracellular iron deficiency.

Science.gov (United States)

Yu, Qilin; Zhang, Bing; Li, Jianrong; Du, Tingting; Yi, Xiao; Li, Mingchun; Chen, Wei; Alvarez, Pedro J J

Graphene oxide (GO)-based materials are increasingly being used in medical materials and consumer products. However, their sublethal effects on biological systems are poorly understood. Here, we report that GO (at 10 to 160 mg/L) induced significant inhibitory effects on the growth of different unicellular organisms, including eukaryotes (i.e. Saccharomyces cerevisiae, Candida albicans, and Komagataella pastoris) and prokaryotes (Pseudomonas fluorescens). Growth inhibition could not be explained by commonly reported cytotoxicity mechanisms such as plasma membrane damage or oxidative stress. Based on transcriptomic analysis and measurement of extra- and intracellular iron concentrations, we show that the inhibitory effect of GO was mainly attributable to iron deficiency caused by binding to the O-functional groups of GO, which sequestered iron and disrupted iron-related physiological and metabolic processes. This inhibitory mechanism was corroborated with supplementary experiments, where adding bathophenanthroline disulfonate-an iron chelating agent-to the culture medium exerted similar inhibition, whereas removing surface O-functional groups of GO decreased iron sequestration and significantly alleviated the inhibitory effect. These findings highlight a potential indirect detrimental effect of nanomaterials (i.e. scavenging of critical nutrients), and encourage research on potential biomedical applications of GO-based materials to sequester iron and enhance treatment of iron-dependent diseases such as cancer and some pathogenic infections.

Dual Actions of Mammalian and Piscine Gonadotropin-Inhibitory Hormones, RFamide-Related Peptides and LPXRFamide Peptides, in the Hypothalamic–Pituitary–Gonadal Axis

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Takayoshi Ubuka

2018-01-01

Full Text Available Gonadotropin-inhibitory hormone (GnIH is a hypothalamic neuropeptide that decreases gonadotropin synthesis and release by directly acting on the gonadotrope or by decreasing the activity of gonadotropin-releasing hormone (GnRH neurons. GnIH is also called RFamide-related peptide in mammals or LPXRFamide peptide in fishes due to its characteristic C-terminal structure. The primary receptor for GnIH is GPR147 that inhibits cAMP production in target cells. Although most of the studies in mammals, birds, and fish have shown the inhibitory action of GnIH in the hypothalamic–pituitary–gonadal (HPG axis, several in vivo studies in mammals and many in vivo and in vitro studies in fish have shown its stimulatory action. In mouse, although the firing rate of the majority of GnRH neurons is decreased, a small population of GnRH neurons is stimulated by GnIH. In hamsters, GnIH inhibits luteinizing hormone (LH release in the breeding season when their endogenous LH level is high but stimulates LH release in non-breeding season when their LH level is basal. Besides different effects of GnIH on the HPG axis depending on the reproductive stages in fish, higher concentration or longer duration of GnIH administration can stimulate their HPG axis. These results suggest that GnIH action in the HPG axis is modulated by sex-steroid concentration, the action of neuroestrogen synthesized by the activity of aromatase stimulated by GnIH, estrogen membrane receptor, heteromerization and internalization of GnIH, GnRH, and estrogen membrane receptors. The inhibitory and stimulatory action of GnIH in the HPG axis may have a physiological role to maintain reproductive homeostasis according to developmental and reproductive stages.

The Inhibitory Mechanism in Learning Ambiguous Words in a Second Language.

Science.gov (United States)

Lu, Yao; Wu, Junjie; Dunlap, Susan; Chen, Baoguo

2017-01-01

Ambiguous words are hard to learn, yet little is known about what causes this difficulty. The current study aimed to investigate the relationship between the representations of new and prior meanings of ambiguous words in second language (L2) learning, and to explore the function of inhibitory control on L2 ambiguous word learning at the initial stage of learning. During a 4-day learning phase, Chinese-English bilinguals learned 30 novel English words for 30 min per day using bilingual flashcards. Half of the words to be learned were unambiguous (had one meaning) and half were ambiguous (had two semantically unrelated meanings learned in sequence). Inhibitory control was introduced as a subject variable measured by a Stroop task. The semantic representations established for the studied items were probed using a cross-language semantic relatedness judgment task, in which the learned English words served as the prime, and the targets were either semantically related or unrelated to the prime. Results showed that response latencies for the second meaning of ambiguous words were slower than for the first meaning and for unambiguous words, and that performance on only the second meaning of ambiguous words was predicted by inhibitory control ability. These results suggest that, at the initial stage of L2 ambiguous word learning, the representation of the second meaning is weak, probably interfered with by the representation of the prior learned meaning. Moreover, inhibitory control may modulate learning of the new meanings, such that individuals with better inhibitory control may more effectively suppress interference from the first meaning, and thus learn the new meaning more quickly.

The Inhibitory Mechanism in Learning Ambiguous Words in a Second Language

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Baoguo Chen

2017-04-01

Full Text Available Ambiguous words are hard to learn, yet little is known about what causes this difficulty. The current study aimed to investigate the relationship between the representations of new and prior meanings of ambiguous words in second language (L2 learning, and to explore the function of inhibitory control on L2 ambiguous word learning at the initial stage of learning. During a 4-day learning phase, Chinese–English bilinguals learned 30 novel English words for 30 min per day using bilingual flashcards. Half of the words to be learned were unambiguous (had one meaning and half were ambiguous (had two semantically unrelated meanings learned in sequence. Inhibitory control was introduced as a subject variable measured by a Stroop task. The semantic representations established for the studied items were probed using a cross-language semantic relatedness judgment task, in which the learned English words served as the prime, and the targets were either semantically related or unrelated to the prime. Results showed that response latencies for the second meaning of ambiguous words were slower than for the first meaning and for unambiguous words, and that performance on only the second meaning of ambiguous words was predicted by inhibitory control ability. These results suggest that, at the initial stage of L2 ambiguous word learning, the representation of the second meaning is weak, probably interfered with by the representation of the prior learned meaning. Moreover, inhibitory control may modulate learning of the new meanings, such that individuals with better inhibitory control may more effectively suppress interference from the first meaning, and thus learn the new meaning more quickly.

Do personality traits predict individual differences in excitatory and inhibitory learning?

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Zhimin eHe

2013-05-01

Full Text Available Conditioned inhibition (CI is demonstrated in classical conditioning when a stimulus is used to signal the omission of an otherwise expected outcome. This basic learning ability is involved in a wide range of normal behaviour - and thus its disruption could produce a correspondingly wide range of behavioural deficits. The present study employed a computer-based task to measure conditioned excitation and inhibition in the same discrimination procedure. Conditioned inhibition by summation test was clearly demonstrated. Additionally summary measures of excitatory and inhibitory learning (difference scores were calculated in order to explore how performance related to individual differences in a large sample of normal participants (n=176 following exclusion of those not meeting the basic learning criterion. The individual difference measures selected derive from two biologically-based personality theories, Gray’s reinforcement sensitivity theory (1982 and Eysenck’s psychoticism, extraversion and neuroticism theory (1991. Following the behavioural tasks, participants completed the behavioural inhibition system/behavioural activation system scales (BIS/BAS and the Eysenck personality questionnaire revised short scale (EPQ-RS. Analyses of the relationship between scores on each of the scales and summary measures of excitatory and inhibitory learning suggested that those with higher BAS (specifically the drive sub-scale and higher EPQ-RS neuroticism showed reduced levels of excitatory conditioning. Inhibitory conditioning was similarly attenuated in those with higher EPQ-RS neuroticism, as well as in those with higher BIS scores. Thus the findings are consistent with higher levels of neuroticism being accompanied by generally impaired associative learning, both inhibitory and excitatory. There was also evidence for some dissociation in the effects of behavioural activation and behavioural inhibition on excitatory and inhibitory learning respectively.

Minimizing Mutual Couping

DEFF Research Database (Denmark)

2010-01-01

Disclosed herein are techniques, systems, and methods relating to minimizing mutual coupling between a first antenna and a second antenna.......Disclosed herein are techniques, systems, and methods relating to minimizing mutual coupling between a first antenna and a second antenna....

Single-molecule analysis of inhibitory pausing states of V1-ATPase.

Science.gov (United States)

Uner, Naciye Esma; Nishikawa, Yoshihiro; Okuno, Daichi; Nakano, Masahiro; Yokoyama, Ken; Noji, Hiroyuki

2012-08-17

V(1)-ATPase, the hydrophilic V-ATPase domain, is a rotary motor fueled by ATP hydrolysis. Here, we found that Thermus thermophilus V(1)-ATPase shows two types of inhibitory pauses interrupting continuous rotation: a short pause (SP, 4.2 s) that occurred frequently during rotation, and a long inhibitory pause (LP, >30 min) that terminated all active rotations. Both pauses occurred at the same angle for ATP binding and hydrolysis. Kinetic analysis revealed that the time constants of inactivation into and activation from the SP were too short to represent biochemically predicted ADP inhibition, suggesting that SP is a newly identified inhibitory state of V(1)-ATPase. The time constant of inactivation into LP was 17 min, consistent with one of the two time constants governing the inactivation process observed in bulk ATPase assay. When forcibly rotated in the forward direction, V(1) in LP resumed active rotation. Solution ADP suppressed the probability of mechanical activation, suggesting that mechanical rotation enhanced inhibitory ADP release. These features were highly consistent with mechanical activation of ADP-inhibited F(1), suggesting that LP represents the ADP-inhibited state of V(1)-ATPase. Mechanical activation largely depended on the direction and angular displacement of forced rotation, implying that V(1)-ATPase rotation modulates the off rate of ADP.

Chemical composition and antimicrobial activity of the essential oil of Hyptis pectinata (l.) Poit

International Nuclear Information System (INIS)

Santos, Patricia O.; Costa, Marcilene de J. C.; Alves, Jose A.B.; Nascimento, Paula F.C.; Melo, Dangelly L.F.M. de; Barbosa Junior, Antonio M.; Trindade, Rita de C.; Blank, Arie F.; Arrigoni-Blank, Maria F.; Alves, Pericles B.; Nascimento, Maria da Paz F. do

2008-01-01

Essential oil was extracted from leaves of Hyptis pectinata using hydrodistillation, and its composition determined using GC-FID and GC-MS. Chemical analysis showed that there was a predominance of sesquiterpenes, of which b-caryophyllene (18.34%), caryophyllene oxide (18.00%) and calamusenone (24.68%) were measured for the first time in the genus Hyptis. Twenty-one compounds were identified, and calamusenone was isolated using preparative thin layer chromatography with a silica gel plate (60 PF 254 ). The minimal inhibitory concentration (MIC) and minimal microbicidal concentration (MMC) were determined for various pathogenic microorganisms. H. pectinata oil was most effective against Gram (+) bacteria and yeasts. (author)

Chemical composition and antimicrobial activity of the essential oil of Hyptis pectinata (l.) Poit

Energy Technology Data Exchange (ETDEWEB)

Santos, Patricia O.; Costa, Marcilene de J. C.; Alves, Jose A.B.; Nascimento, Paula F.C.; Melo, Dangelly L.F.M. de; Barbosa Junior, Antonio M.; Trindade, Rita de C. [Universidade Federal de Sergipe, Aracaju, SE (Brazil). Dept. de Morfologia]. E-mail: ritinhat@hotmail.com; Blank, Arie F. [Universidade Federal de Sergipe, Aracaju, SE (Brazil). Dept. de Engenharia Agronomica; Arrigoni-Blank, Maria F. [Nucleo de Ciencias Biologicas, Itabaiana, SE (Brazil). Campus Prof. Alberto Carvalho; Alves, Pericles B. [Universidade Federal de Sergipe, Aracaju, SE (Brazil). Dept. de Quimica; Nascimento, Maria da Paz F. do [Universidade Federal de Sao Carlos, SP (Brazil). Dept. de Quimica

2008-07-01

Essential oil was extracted from leaves of Hyptis pectinata using hydrodistillation, and its composition determined using GC-FID and GC-MS. Chemical analysis showed that there was a predominance of sesquiterpenes, of which b-caryophyllene (18.34%), caryophyllene oxide (18.00%) and calamusenone (24.68%) were measured for the first time in the genus Hyptis. Twenty-one compounds were identified, and calamusenone was isolated using preparative thin layer chromatography with a silica gel plate (60 PF{sub 254}). The minimal inhibitory concentration (MIC) and minimal microbicidal concentration (MMC) were determined for various pathogenic microorganisms. H. pectinata oil was most effective against Gram (+) bacteria and yeasts. (author)

Inhibitory and bactericidal potential of crude acetone extracts of Combretum molle (Combretaceae) on drug-resistant strains of Helicobacter pylori.

Science.gov (United States)

Njume, Collise; Afolayan, Anthony J; Samie, Amidou; Ndip, Roland N

2011-10-01

Infection with Helicobacter pylori is strongly associated with a number of gastroduodenal pathologies. Antimicrobial resistance to commonly-used drugs has generated a considerable interest in the search for novel therapeutic compounds from medicinal plants. As an ongoing effort of this search, the susceptibility of 32 clinical strains of H. pylori and a reference strain-NCTC 11,638-was evaluated against five solvent extracts of Combretum molle, a plant widely used for the treatment of gastric ulcers and other stomach-related morbidities in South Africa. The extracts were screened for activity by the agar-well diffusion method, and the most active one of them was tested against the same strains by micro-broth dilution and time kill assays. Metronidazole and amoxicillin were included in these experiments as positive control antibiotics. The solvent extracts all demonstrated anti-H. pylori activity with zone diameters of inhibition between 0 and 38 mm. The most potent anti-H. pylori activity was demonstrated by the acetone extract, to which 87.5% of the clinical strains were susceptible. The minimum inhibitory concentration (MIC90) values for this extract ranged from 1.25 to 5.0 mg/mL while those for amoxicillin and metronidazole ranged from 0.001 to 0.94 mg/mL and from 0.004 to 5.0 mg/mL respectively. The acetone extract was highly bactericidal at a concentration of 2.5 and 5.0 mg/mL, with complete elimination of the test organisms in 24 hours. Its inhibitory activity was better than that of metronidazole (pmolle may contain therapeutically-useful compounds against H. pylori, which are mostly concentrated in the acetone extract.

Effect of O-methylated and glucuronosylated flavonoids from Tamarix gallica on α-glucosidase inhibitory activity: structure-activity relationship and synergistic potential.

Science.gov (United States)

Ben Hmidene, Asma; Smaoui, Abderrazak; Abdelly, Chedly; Isoda, Hiroko; Shigemori, Hideyuki

2017-03-01

O-Methylated and glucuronosylated flavonoids were isolated from Tamarix gallica as α-glucosidase inhibitors. Structure-activity relationship of these flavonoids suggests that catechol moiety and glucuronic acid at C-3 are factors in the increase in α-glucosidase inhibitory activity. Furthermore, rhamnetin, tamarixetin, rhamnazin, KGlcA, KGlcA-Me, QGlcA, and QGlcA-Me exhibit synergistic potential when applied with a very low concentration of acarbose to α-glucosidase from rat intestine.

Inhibitory Effect of Capparis spinosa Extract on Pancreatic Alpha-Amylase Activity

Directory of Open Access Journals (Sweden)

Mostafa Selfayan

2016-04-01

Full Text Available Background Diabetes mellitus is a metabolic disorder characterized by high blood glucose level caused due to deficiency of insulin secretion or insulin function. The inhibition of carbohydrate hydrolyzing enzymes such as α-amylase can be an important strategy for decrease postprandial blood glucose level in patients with type II diabetes. Plants contains different chemical constituents with potential for inhibition of α-amylase and hence maybe used as therapeutic. Objectives The aim of the present study is to investigate the effect of the ethanolic extract of Capparis spinosa on pancreatic α-amylase activities to find out the relevance of the plant in controlling blood sugar. Materials and Methods In this experimental study, root and leaves of C. spinosa were tested for α-amylase inhibition. Different concentrations (1.56, 3.12, 6.25, 12.5 and 25 mg/mL of extracts were incubated with enzyme substrate solution and the spectrometric method used for measure enzyme activity. Also acarbose was used as the standard inhibitor. Results Both root and leaves extracts showed inhibition of α-amylase (root = 97.31% and leaves = 98.92%. The root and leaves extracts of C. spinosa exhibited appreciable α-amylase inhibitory activity with an IC50 values 5.93 mg/mL and 3.89 mg/mL respectively, when compared with acarbose (IC50 value 0.038 mg/mL. Conclusions This study supports that root and leaves extracts of C. spinosa exhibit considerable α-amylase inhibitory activities. These results could be useful for developing functional foods by combination of plant-based foods for treatment of diabetes mellitus.

Neuroprotective effect of seaweeds inhabiting South Indian coastal area (Hare Island, Gulf of Mannar Marine Biosphere Reserve): Cholinesterase inhibitory effect of Hypnea valentiae and Ulva reticulata.

Science.gov (United States)

Suganthy, N; Karutha Pandian, S; Pandima Devi, K

2010-01-14

Alzheimer's disease (AD) is the most common form of dementia, which is one of the four leading causes of death in developed nations. Until date the only symptomatic treatment for this disease is based on the "cholinergic hypothesis" where the drugs enhance acetylcholine levels in the brain by inhibiting acetylcholinesterase (AChE). In the course for screening cholinesterase inhibitors about eight seaweeds, with wide pharmaceutical applications, were collected from Hare Island, Gulf of Mannar, Marine Biosphere Reserve, Tamil Nadu, India. Inhibitory effect of methanol extract of the seaweeds was studied in vitro by incubating various concentration of the extract with AChE or butyryl cholinesterase (BuChE) and assessing their activities by Ellman's colorimetric method. Kinetic parameters like IC(50), K(i) and V(max) were also analyzed. The results showed that of the eight seaweeds screened Hypnea valentiae, Padina gymnospora, Ulva reticulata and Gracilaria edulis exhibited inhibitory activity to AChE with IC(50) value of 2.6, 3.5, 10 and 3mg/ml respectively, while H. valentiae, Enteromorpha intestinalis, Dictyota dichotoma and U. reticulata showed 50% inhibition to BuChE at concentration 3.9, 7, 6.5 and 10mg/ml respectively. The inhibitory activities of the seaweed extracts were comparable to the standard drug donepezil. Enzyme kinetic analysis showed that algal extracts exhibited mixed type inhibition (partial noncompetitive inhibition). Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

Novel nootropic dipeptide Noopept increases inhibitory synaptic transmission in CA1 pyramidal cells.

Science.gov (United States)

Kondratenko, Rodion V; Derevyagin, Vladimir I; Skrebitsky, Vladimir G

2010-05-31

Effects of newly synthesized nootropic and anxiolytic dipeptide Noopept on inhibitory synaptic transmission in hippocampal CA1 pyramidal cells were investigated using patch-clamp technique in whole-cell configuration. Bath application of Noopept (1 microM) significantly increased the frequency of spike-dependant spontaneous IPSCs whereas spike-independent mIPSCs remained unchanged. It was suggested that Noopept mediates its effect due to the activation of inhibitory interneurons terminating on CA1 pyramidal cells. Results of current clamp recording of inhibitory interneurons residing in stratum radiatum confirmed this suggestion. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

Effects of prenatal substance exposure on neurocognitive correlates of inhibitory control success and failure.

Science.gov (United States)

Roos, Leslie E; Beauchamp, Kathryn G; Pears, Katherine C; Fisher, Philip A; Berkman, Elliot T; Capaldi, Deborah

2017-01-01

Adolescents with prenatal substance (drug and alcohol) exposure exhibit inhibitory control (IC) deficits and aberrations in associated neural function. Nearly all research to date examines exposure to individual substances, and a minimal amount is known about the effects of heterogeneous exposure-which is more representative of population exposure levels. Using functional magnetic resonance imaging (fMRI), we investigated IC (Go/NoGo) in heterogeneously exposed (n = 7) vs. control (n = 7) at-risk adolescents (ages 13-17). The fMRI results indicated multiple IC processing differences consistent with a more immature developmental profile for exposed adolescents (Exposed  >  Nonexposed: NoGo > Go: right ventrolateral prefrontal cortex, right cuneus, and left inferior parietal lobe; NoGo > false alarm: occipital lobe; Go > false alarm: right anterior prefrontal cortex). Simple effects suggest exposed adolescents exhibited exaggerated correct trial but decreased incorrect trial activation. Results provide initial evidence that prenatal exposure across substances creates similar patterns of atypical brain activation to IC success and failure.

Prevalence and concentration of bacterial pathogens in raw produce and minimally processed packaged salads produced in and for the Netherlands.

Science.gov (United States)

Wijnands, Lucas M; Delfgou-van Asch, Ellen H M; Beerepoot-Mensink, Marieke E; van der Meij-Florijn, Alice; Fitz-James, Ife; van Leusden, Frans M; Pielaat, Annemarie

2014-03-01

Recent outbreaks with vegetable or fruits as vehicles have raised interest in the characterization of the public health risk due to microbial contamination of these commodities. Because qualitative and quantitative data regarding prevalence and concentration of various microbes are lacking, we conducted a survey to estimate the prevalence and contamination level of raw produce and the resulting minimally processed packaged salads as sold in The Netherlands. A dedicated sampling plan accounted for the amount of processed produce in relation to the amount of products, laboratory capacity, and seasonal influences. Over 1,800 samples of produce and over 1,900 samples of ready-to-eat mixed salads were investigated for Salmonella enterica serovars, Campylobacter spp., Escherichia coli O157, and Listeria monocytogenes. The overall prevalence in raw produce varied between 0.11% for E. coli O157 and L. monocytogenes and 0.38% for Salmonella. Prevalence point estimates for specific produce/pathogen combinations ranged for Salmonella from 0.53% in iceberg lettuce to 5.1% in cucumber. For Campylobacter, this ranged from 0.83% in endive to 2.7% in oak tree lettuce. These data will be used to determine the public health risk posed by the consumption of ready-to-eat mixed salads in The Netherlands.

Inhibitory effects of kale ingestion on metabolism by cytochrome P450 enzymes in rats.

Science.gov (United States)

Yamasaki, Izumi; Yamada, Masayoshi; Uotsu, Nobuo; Teramoto, Sachiyuki; Takayanagi, Risa; Yamada, Yasuhiko

2012-01-01

Kale (Brassica oleracea L. var acephala DC) is a leafy green vegetable belonging to the cabbage family (Brassicaceae) that contains a large amount of health-promoting phytochemicals. There are any reports about the effects of kale ingestion on the chemoprevention function and mechanism, but the interactions between kale and drugs have not been researched. We investigated the effects of kale intake on cytochrome P450 (CYP) metabolism by using cocktail probe drugs, including midazolam (for CYP3A4), caffeine (for CYP1A2), dextromethorphan (for CYP2D6), tolbutamide (for CYP2C9), omeprazole (for CYP2C19), and chlorzoxazone (for CYP2E1). Cocktail drugs were administered into rats treated with kale and cabbage (2000 mg/kg) for a week. The results showed that kale intake induced a significant increase in plasma levels and the AUC of midazolam, caffeine, and dextromethorphan. In addition, the plasma concentration and AUC of omeprazole tended to increase. Additionally, no almost differences in the mRNA expression levels of CYP enzymes in the liver were observed. In conclusion, kale ingestion was considered to have an inhibitory effect on the activities of CYP3A4, 1A2, 2D6, and 2C19 for a reason competitive inhibition than inhibitory changes in the mRNA expressions.

Assessment of the inhibitory effects of pyrethroids against human carboxylesterases

Energy Technology Data Exchange (ETDEWEB)

Lei, Wei [The Second Affiliated Hospital of Dalian Medical University, Dalian 110623 (China); Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Wang, Dan-Dan; Dou, Tong-Yi [Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Hou, Jie [Dalian Medical University, Dalian 116044 (China); Feng, Liang; Yin, Heng [Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Luo, Qun [Beijing National Laboratory for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China); Sun, Jie [The Second Affiliated Hospital of Dalian Medical University, Dalian 110623 (China); Ge, Guang-Bo, E-mail: geguangbo@dicp.ac.cn [Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China); Yang, Ling [Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)

2017-04-15

Pyrethroids are broad-spectrum insecticides that widely used in many countries, while humans may be exposed to these toxins by drinking or eating pesticide-contaminated foods. This study aimed to investigate the inhibitory effects of six commonly used pyrethroids against two major human carboxylesterases (CES) including CES1 and CES2. Three optical probe substrates for CES1 (DME, BMBT and DMCB) and a fluorescent probe substrate for CES2 (DDAB) were used to characterize the inhibitory effects of these pyrethroids. The results demonstrated that most of the tested pyrethroids showed moderate to weak inhibitory effects against both CES1 and CES2, but deltamethrin displayed strong inhibition towards CES1. The IC{sub 50} values of deltamethrin against CES1-mediated BMBT, DME, and DMCB hydrolysis were determined as 1.58 μM, 2.39 μM, and 3.3 μM, respectively. Moreover, deltamethrin was cell membrane permeable and capable of inhibition endogenous CES1 in living cells. Further investigation revealed that deltamethrin inhibited CES1-mediated BMBT hydrolysis via competitive manner but noncompetitively inhibited DME or DMCB hydrolysis. The inhibition behaviors of deltamethrin against CES1 were also studied by molecular docking simulation. The results demonstrated that CES1 had at least two different ligand-binding sites, one was the DME site and another was the BMBT site which was identical to the binding site of deltamethrin. In summary, deltamethrin was a strong reversible inhibitor against CES1 and it could tightly bind on CES1 at the same ligand-binding site as BMBT. These findings are helpful for the deep understanding of the interactions between xenobiotics and CES1. - Highlights: • The inhibitory effects of six commonly used pyrethroids on human carboxylesterases were investigated. • Deltamethrin displayed strong inhibitory effects against human carboxylesterase 1 (CES1). • Deltamethrin was cell membrane permeable and could inhibit intracellular CES1 in living

Assessment of the inhibitory effects of pyrethroids against human carboxylesterases

International Nuclear Information System (INIS)

Lei, Wei; Wang, Dan-Dan; Dou, Tong-Yi; Hou, Jie; Feng, Liang; Yin, Heng; Luo, Qun; Sun, Jie; Ge, Guang-Bo; Yang, Ling

2017-01-01

Pyrethroids are broad-spectrum insecticides that widely used in many countries, while humans may be exposed to these toxins by drinking or eating pesticide-contaminated foods. This study aimed to investigate the inhibitory effects of six commonly used pyrethroids against two major human carboxylesterases (CES) including CES1 and CES2. Three optical probe substrates for CES1 (DME, BMBT and DMCB) and a fluorescent probe substrate for CES2 (DDAB) were used to characterize the inhibitory effects of these pyrethroids. The results demonstrated that most of the tested pyrethroids showed moderate to weak inhibitory effects against both CES1 and CES2, but deltamethrin displayed strong inhibition towards CES1. The IC 50 values of deltamethrin against CES1-mediated BMBT, DME, and DMCB hydrolysis were determined as 1.58 μM, 2.39 μM, and 3.3 μM, respectively. Moreover, deltamethrin was cell membrane permeable and capable of inhibition endogenous CES1 in living cells. Further investigation revealed that deltamethrin inhibited CES1-mediated BMBT hydrolysis via competitive manner but noncompetitively inhibited DME or DMCB hydrolysis. The inhibition behaviors of deltamethrin against CES1 were also studied by molecular docking simulation. The results demonstrated that CES1 had at least two different ligand-binding sites, one was the DME site and another was the BMBT site which was identical to the binding site of deltamethrin. In summary, deltamethrin was a strong reversible inhibitor against CES1 and it could tightly bind on CES1 at the same ligand-binding site as BMBT. These findings are helpful for the deep understanding of the interactions between xenobiotics and CES1. - Highlights: • The inhibitory effects of six commonly used pyrethroids on human carboxylesterases were investigated. • Deltamethrin displayed strong inhibitory effects against human carboxylesterase 1 (CES1). • Deltamethrin was cell membrane permeable and could inhibit intracellular CES1 in living cells

Correlation between enzymes inhibitory effects and antioxidant ...

African Journals Online (AJOL)

... and phytochemical content of fractions was investigated. The n-butanol fraction showed significant α-glucosidase and α-amylase inhibitory effects (IC50 values 15.1 and 39.42 μg/ml, respectively) along with the remarkable antioxidant activity when compared to the other fractions. High performance liquid chromatography ...

Antibacterial activity of root and leaf extracts of Jatropha zeyheri ...

African Journals Online (AJOL)

Acetone extract of the root exhibited minimal inhibitory concentration (MIC) of 0.39 mg/ml against Salmonella spp. followed by methanol and acetone extracts of the root (0.78 mg/ml) against Serratia marcescens. Methanol extract of the leaf exhibited MIC of 3.13 mg/ml against Staphylococcus aureus. This study validates the ...

Inhibitory mechanism of influence of thyroid hormones on cognitive function of the brain

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Rodynsky A.G.

2017-06-01

Full Text Available In experiments on young rats there were stu¬died changes in the fatty acid spectrum of fraction of free fatty acids (FFA of neocortex and hippocampus in con¬ditions of thyroid dysfunction. Elevated levels of thyroid hormones caused accumulation of polyunsaturated linoleic and linolenic acids in the neocortex by 2 times, in the hippocampus – by 52%. State of hypo¬thyroidism also contributed to the increase of C18: 2,3 in the neocortex by 74.4%. Growth of share of unsaturated fatty acid fraction in the content of fatty acid spectrum of neocortex also was accompanied by decrease in saturated C16:0 and C21:0 by 25% and 36% res¬pectively. Increase of the level of unsaturated fatty acids fraction of the cerebral cortex is possibly associated with the decrease in "unsaturation" structure of lipids, which in its turn may enhance serotonergic synaptic activity. Research of concentration of neuromediator amino acids in neocortex showed increase of serotonin content both in conditions of hyperthyroidism and hypothyroidism. In conditions of hyperthyroidism increased content of GABA was observed. Activity of serotonin- and GABA- ergic neurotransmitter systems of the brain in conditions of hyperthyroidism can be considered as increase of inhibitory processes in the effect of feedback. In conditions of experimental hypothyroidism activation of the inhibitory effects of CNS serotonergic system may be one of the ways to reduce the metabolism.

Can Working Memory and Inhibitory Control Predict Second Language Learning in the Classroom?

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Jared A. Linck

2015-10-01

Full Text Available The role of executive functioning in second language (L2 aptitude remains unclear. Whereas some studies report a relationship between working memory (WM and L2 learning, others have argued against this association. Similarly, being bilingual appears to benefit inhibitory control, and individual differences in inhibitory control are related to online L2 processing. The current longitudinal study examines whether these two components of executive functioning predict learning gains in an L2 classroom context using a pretest/posttest design. We assessed 25 university students in language courses, who completed measures of WM and inhibitory control. They also completed a proficiency measure at the beginning and end of a semester and reported their grade point average (GPA. WM was positively related to L2 proficiency and learning, but inhibitory control was not. These results support the notion that WM is an important component of L2 aptitude, particularly for predicting the early stages of L2 classroom learning.

Inhibitory Control Mediates the Association between Perceived Stress and Secure Relationship Quality

OpenAIRE

Toria Herd; Mengjiao Li; Dominique Maciejewski; Jacob Lee; Kirby Deater-Deckard; Brooks King-Casas; Jungmeen Kim-Spoon

2018-01-01

Past research has demonstrated negative associations between exposure to stressors and quality of interpersonal relationships among children and adolescents. Nevertheless, underlying mechanisms of this association remain unclear. Chronic stress has been shown to disrupt prefrontal functioning in the brain, including inhibitory control abilities, and evidence is accumulating that inhibitory control may play an important role in secure interpersonal relationship quality, including peer problems...

Inhibitory and Working Memory Demands of the Day-Night Task in Children

Science.gov (United States)

Simpson, Andrew; Riggs, Kevin J.

2005-01-01

Gerstadt, Hong, and Diamond (1994) investigated the development of inhibitory control in children aged 3 1/2 - 7 years using the day-night task. In two studies we build on Gerstadt et al.'s findings with a measure of inhibitory control that can be used throughout childhood. In Study 1 (twenty-four 3 1/2-year-olds and sixteen 5-year-olds) we…

Npas4 regulates excitatory-inhibitory balance within neural circuits through cell-type-specific gene programs.

Science.gov (United States)

Spiegel, Ivo; Mardinly, Alan R; Gabel, Harrison W; Bazinet, Jeremy E; Couch, Cameron H; Tzeng, Christopher P; Harmin, David A; Greenberg, Michael E

2014-05-22

The nervous system adapts to experience by inducing a transcriptional program that controls important aspects of synaptic plasticity. Although the molecular mechanisms of experience-dependent plasticity are well characterized in excitatory neurons, the mechanisms that regulate this process in inhibitory neurons are only poorly understood. Here, we describe a transcriptional program that is induced by neuronal activity in inhibitory neurons. We find that, while neuronal activity induces expression of early-response transcription factors such as Npas4 in both excitatory and inhibitory neurons, Npas4 activates distinct programs of late-response genes in inhibitory and excitatory neurons. These late-response genes differentially regulate synaptic input to these two types of neurons, promoting inhibition onto excitatory neurons while inducing excitation onto inhibitory neurons. These findings suggest that the functional outcomes of activity-induced transcriptional responses are adapted in a cell-type-specific manner to achieve a circuit-wide homeostatic response. Copyright © 2014 Elsevier Inc. All rights reserved.

Phenotypic characterisation and assessment of the inhibitory ...

African Journals Online (AJOL)

Six strains of Lactobacillus spp. were isolated from fermenting corn slurry, fresh cow milk, and the faeces of pig, albino rat, and human infant. Their inhibitory action was tested against some spoilage and pathogenic bacteria. Lactobacillus acidophilus isolated from milk was found to display a higher antagonistic effect with ...

Phenotypic characterisation and assessment of the inhibitory ...

African Journals Online (AJOL)

Fred

inhibitory potential of Lactobacillus isolates from different sources. Oyetayo, V.O.. Department of ... Six strains of Lactobacillus spp. were isolated from fermenting corn slurry, fresh cow milk, and the faeces of pig, albino rat, and human ... the growth of some pathogens by Lactobacillus reuteri BSA 13, obtained from pig faeces.

Inhibitory Effects of 5,6,7-Trihydroxyflavones on Tyrosinase

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Jun Kawabata

2007-01-01

Full Text Available Baicalein (1, 6-hydroxyapigenin (6, 6-hydroxygalangin (13 and 6-hydroxy-kaempferol (14, which are naturally occurring flavonoids from a set of 14 hydroxy-flavones tested, exhibited high inhibitory effects on tyrosinase with respect to L-DOPA,while each of the 5,6,7-trihydroxyflavones 1, 6, 13 or 14 acted as a cofactor tomonophenolase. Moreover, 6-hydroxykaempferol (14 showed the highest activity andwas a competitive inhibitor of tyrosinase compared to L-DOPA. 5,6,7-Trihydroxyflavones 1, 6, 13 or 14 showed also high antioxidant activities. Hence, weconclude that the 5,6,7-trihydroxy-flavones are useful as good depigmentation agentswith inhibitory effects in addition to their antioxidant properties.

Alpha amylase and Alpha glucosidase inhibitory effects of aqueous stem extract of Salacia oblonga and its GC-MS analysis

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Gladis Raja Malar Chelladurai

2018-05-01

Full Text Available ABSTRACT Our present investigation deals with the phytochemical screening, estimation of total flavonoids, terpenoids and tannin contents to evaluate the anti-diabetic activities of Salacia oblonga stem followed by GC-MS analysis. It explores the natural compounds and the potential α-amylase and α-glucosidase inhibitory actions of stem extracts. The aqueous stem extract was selected from other extracts (ethanol, acetone, petroleum ether and chloroform for the in vitro study of anti-diabetic activity by alpha amylase and alpha glucosidase inhibitory assays. The stem extract was also analyzed by gas chromatography mass spectrometry to identify the natural chemical components. Phytochemical analysis of aqueous stem extract showed major classes of secondary metabolites such as phenols, flavonoids, alkaloids, terpenoids, tannins, saponins. The total flavonoid, terpenoid, and tannin contents were quantified as 19.82±0.06 mg QE/g, 96.2±0.20 mg/g and 11.25±0.03 mg TAE/g respectively. The percentage inhibition of assays showed maximum inhibitory effects (59.46±0.04% and 68.51±0.01% at a concentration of 100 mg/mL. The IC50 values of stem extract was found to be 73.56 mg/mL and 80.90 mg/mL for alpha amylase and alpha glucosidase inhibition. Fifteen chemical constituents were found by GC-MS analysis. This study suggest the aqueous stem extract of Salacia oblonga might be considered as potential source of bio active constituents with excellent antidiabetic activity.

Reward, interrupted: Inhibitory control and its relevance to addictions.

Science.gov (United States)

Jentsch, James David; Pennington, Zachary T

2014-01-01

There are broad individual differences in the ability to voluntarily and effortfully suppress motivated, reward-seeking behaviors, and this review presents the hypothesis that these individual differences are relevant to addictive disorders. On one hand, cumulative experience with drug abuse appears to alter the molecular, cellular and circuit mechanisms that mediate inhibitory abilities, leading to increasingly uncontrolled patterns of drug-seeking and -taking. On the other, native inter-individual differences in inhibitory control are apparently a risk factor for aspects of drug-reinforced responding and substance use disorders. In both cases, the behavioral manifestation of poor inhibitory abilities is linked to relatively low striatal dopamine D2-like receptor availability, and evidence is accumulating for a more direct contribution of striatopallidal neurons to cognitive control processes. Mechanistic research is now identifying genes upstream of dopamine transmission that mediate these relationships, as well as the involvement of other neurotransmitter systems, acting alone and in concert with dopamine. The reviewed research stands poised to identify new mechanisms that can be targeted by pharmacotherapies and/or by behavioral interventions that are designed to prevent or treat addictive behaviors and associated behavioral pathology. This article is part of a Special Issue entitled 'NIDA 40th Anniversary Issue'. Copyright © 2013 Elsevier Ltd. All rights reserved.