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1

Minimum inhibitory concentration distribution in environmental Legionella spp. isolates.  

PubMed

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 ?-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. PMID:25473976

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

2014-12-01

2

Bacterial maximum non-inhibitory and minimum inhibitory concentrations of different water activity depressing solutes.  

PubMed

The NaCl MNICs (maximum non-inhibitory concentrations) and MICs (minimum inhibitory concentrations) for growth of various strains of six bacterial species were determined and then compared with those obtained for seven other solutes. The influence of prior growth conditions on the MNICs and MICs was also evaluated. No significant changes on the MNICs and MICs were found among the strains studied within each species. Among all factors investigated, only growth phase -for Gram-negatives- and growth at high NaCl concentrations led to a change in the NaCl MNICs. Species could be classified depending on its NaCl MNICs and MICs (in decreasing order) as follows: Staphylococcus aureus, Listeria monocytogenes, Cronobacter sakazakii, Enterococcus faecium, Escherichia coli and Salmonella Typhimurium. Similar results were obtained for KCl, LiCl, and sodium acetate, but not for the remaining solutes investigated (sucrose, glycerol, MgCl2 and CaCl2). Results obtained indicate that, in general, Gram-negatives showed lower MNICs and MICs than Gram-positives for all the solutes, S. aureus being the most solute tolerant microorganism. When compared on a molar basis, glycerol showed the highest MNICs and MICs for all the microorganisms -except for S. aureus- and LiCl the lowest ones. NaCl MNICs and MICs were not significantly different from those of KCl when compared on a molar basis. Therefore, the inhibitory action of NaCl could not be linked to the specific action of Na(+). Results also showed that the Na(+) tolerance of some species was Cl(-) dependent whereas for others it was not, and that factors others than aw-decrease contribute to the inhibitory action of LiCl, CaCl2 and MgCl2. PMID:25090605

Cebrián, G; Arroyo, C; Mańas, P; Condón, S

2014-10-01

3

Minimum inhibitory concentrations of Staphylococcus aureus recovered from clinical and subclinical cases of bovine mastitis.  

PubMed

Antimicrobials are often used for treatment of bovine mastitis and the possibility of selection for resistant bacteria must be considered. The objectives of this study were to determine the minimum inhibitory concentration of Staphylococcus aureus recovered from cases of clinical and subclinical bovine mastitis, and to determine the prevalence of multidrug resistance in this population. Milk samples were collected from cows on commercial dairy herds (n=13), including quarters (n=1,574) of cows with subclinical mastitis cases, and cows experiencing clinical mastitis cases (n=608). Selected Staph. aureus isolates, obtained from clinical (n=58) and subclinical (n=58) mastitis cases, were used to determine minimum inhibitory concentrations of 12 selected antimicrobials. Of Staph. aureus isolates tested, 87 (75%) did not exhibit resistance to any antimicrobial, 28 (24.1%) exhibited resistance to 1 (n=21) or 2 (n=7) classes of antimicrobials, and 1 (0.9%) exhibited multidrug resistance. All Staph. aureus (clinical and subclinical cases) were inhibited by the range of concentrations tested for ceftiofur and oxacillin. Moreover, no isolates obtained from clinical mastitis cases exhibited resistance to cephalothin, penicillin-novobiocin, or sulfadimethoxine. Of isolates, 3 exhibited resistance to enrofloxacin. Of isolates exhibiting resistance to more than 1 antimicrobial, independent of antimicrobial class, the combination of erythromycin and tetracycline, and ampicillin and penicillin accounted for the majority of resistance. Of isolates tested, 19% were resistant to tetracycline and 14% were resistant to penicillin. Survival curves of Staph. aureus relative to minimum inhibitory concentration demonstrated heterogeneity among case types for ceftiofur, cephalothin, and erythromycin. Multidrug resistance was identified in only 1 isolate obtained from a single farm. PMID:22459838

Oliveira, L; Langoni, H; Hulland, C; Ruegg, P L

2012-04-01

4

Minimum inhibitory concentrations of some antimicrobial drugs against bacteria causing uterine infections in cattle.  

PubMed

The minimum inhibitory concentrations (MICs) of oxytetracycline, cephapirin, cephapirin/mecillinam, cefquinome, ceftiofur and enrofloxacin, candidate antibiotics for the principal bacteria associated with uterine infections: Escherichia coli, Arcanobacterium pyogenes and the anaerobic bacteria Fusobacterium necrophorum and Prevotella melaninogenicus, were determined by the agar dilution method. The bacteria were isolated from animals with clinical metritis and/or endometritis. For E coli, cefquinome and enrofloxacin had the lowest MIC90 and MIC50 values (< 0.06 microg/ml), and oxytetracycline and cephapirin had the highest values. For A pyogenes, oxytetracycline had the highest MIC50 value (16 microg/ml), but all the cephalosporins had values below 0.06 microg/ml. For the anaerobic bacteria, enrofloxacin and oxytetracycline had the highest MIC50 values but all the cephalosporins had values of 0.06 microg/ml or below. PMID:15499809

Sheldon, I M; Bushnell, M; Montgomery, J; Rycroft, A N

2004-09-25

5

Minimum inhibitory concentrations of amphotericin B, azoles and caspofungin against Candida species are reduced by farnesol.  

PubMed

The objective of this study was to evaluate the antifungal activity of farnesol and its interaction with traditional antifungals against drug-resistant strains of Candida species. To do so, we studied the minimum in vitro inhibitory concentration (MIC) of amphotericin B (AMB), fluconazole (FLC), itraconazole (ITC), caspofungin (CAS) and farnesol against 45 isolates of Candida spp., i.e., 24 C. albicans, 16 C. parapsilosis and 5 C. tropicalis through the use of the broth microdilution method. Then, the isolates were tested with the combination of farnesol plus drugs to which they were previously found to be resistant. Additionally, the strains were pre-incubated at sub-inhibitory farnesol concentrations and their antifungal susceptibilities were re-evaluated. We found the MIC values for farnesol varied from 4.68-150 µM for Candida spp., with 19 isolates having a MIC >?1 mg/l, 18 a MIC ??64 mg/l, 35 having a MIC ??1 mg/l and 6 isolates a MIC ??2 mg/l or were resistant to AMB, FLC, ITC and CAS, respectively. Significant MIC reductions were observed when farnesol and antifungal drugs were combined (P

Cordeiro, Rossana A; Teixeira, Carlos E C; Brilhante, Raimunda S N; Castelo-Branco, Débora S C M; Paiva, Manoel A N; Giffoni Leite, Joăo J; Lima, Daniel T; Monteiro, André J; Sidrim, José J C; Rocha, Marcos F G

2013-01-01

6

A new method for determining the minimum inhibitory concentration of essential oils.  

PubMed

A new microdilution method has been developed for determining the minimum inhibitory concentration (MIC) of oil-based compounds. The redox dye resazurin was used to determine the MIC of a sample of the essential oil of Melaleuca alternifolia (tea tree) for a range of Gram-positive and -negative bacteria. Use of 0.15% (w/v) agar as a stabilizer overcame the problem of adequate contact between the oil and the test bacteria and obviated the need to employ a chemical emulsifier. A rapid version of the assay was also developed for use as a screening method. A comparison of visual and photometric reading of the microtitre plates showed that results could be assessed without instrumentation; moreover, if the rapid assay format was used, rigorous asepsis was not necessary. Accuracy of the resazurin method was confirmed by plate counting from microwells and MIC values were compared with results obtained using an agar dilution assay. The MIC results obtained by the resazurin method were slightly lower than those obtained by agar dilution. PMID:9633651

Mann, C M; Markham, J L

1998-04-01

7

Minimum inhibitory concentrations for selected antimicrobial agents against Fusobacterium necrophorum isolated from hepatic abscesses in cattle and sheep.  

PubMed

Minimum inhibitory concentrations for 35 antimicrobial agents against 100 Fusobacterium necrophorum isolates from hepatic abscesses in sheep and cattle were determined. Twelve of the thirteen beta-lactam antibiotics tested inhibited growth of 100% of strains tested. Of the remaining antimicrobial agents, extensive susceptibility was found for: spiramycin, josamycin, lincomycin, tylosin, oxytetracycline, chlortetracycline, rufloxacin, metronidazole, cotrimoxazole, sulfadimethoxine, virginiamycin and fosfomycin. PMID:9049945

Mateos, E; Piriz, S; Valle, J; Hurtado, M; Vadillo, S

1997-02-01

8

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

PubMed

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. PMID:22193301

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

2012-03-21

9

Evaluation of minimum inhibitory and minimum bactericidal concentration of nano-silver base inorganic anti-microbial agent (Novaron®) against streptococcus mutans  

PubMed Central

Objective: We attempted to find the possibility of determining the minimum inhibitory concentration and minimum bactericidal concentration needed for nano-silver base inorganic anti-microbial agent (Novaron® AG 300, AG 1100) against Streptococcus mutans in vitro using broth dilution assay. Materials and Methods: An ampoule of freeze-dried S. mutans NCTC reference strain was revived, and the colony-forming units (CFU) were calculated. The MIC and MBC was determined by broth dilution assay using different concentrations of Novaron® AG 300 and Novaron® AG 1100 against 1 × 105 CFU/ml of S. mutans. Results: The MIC and MBC of Novaron® AG 300 and Novaron® AG 1100 against S. mutans were found to be 40 ?g/ml. Conclusions: Novaron® has anti-bacterial effect against S. mutans. Further studies are needed to explore the applicability of these silver-supported anti- microbial agents in clinical dentistry. PMID:23293483

Holla, Goda; Yeluri, Ramakrishna; Munshi, Autar Krishen

2012-01-01

10

Minimum Inhibitory Concentrations for Selected Antimicrobial Agents Against Organisms Isolated from the Mammary Glands of Dairy Heifers in New Zealand and Denmark  

Microsoft Academic Search

Minimum inhibitory concentrations were deter- mined for selected antimicrobial agents against 872 bacteria isolated from intramammary infections in heifers in New Zealand (n = 401) and Denmark (n = 471). These values were reported in micrograms per milliliters. Antimicrobial agents tested against iso- lates from New Zealand were penicillin, cloxacillin, cephapirin, ceftiofur, novobiocin, enrofloxacin, erythromycin, and pirlimycin. The minimum inhibi-

S. A. Salmon; J. L. Watts; F. M. Aarestrup; J. W. Pankey; R. J. Yancey Jr.

1998-01-01

11

Minimum inhibitory concentrations for selected antimicrobial agents against organisms isolated from the mammary glands of dairy heifers in New Zealand and Denmark.  

PubMed

Minimum inhibitory concentrations were determined for selected antimicrobial agents against 872 bacteria isolated from intramammary infections in heifers in New Zealand (n = 401) and Denmark (n = 471). These values were reported in micrograms per milliliters. Antimicrobial agents tested against isolates from New Zealand were penicillin, cloxacillin, cephapirin, ceftiofur, novobiocin, enrofloxacin, erythromycin, and pirlimycin. The minimum inhibitory concentrations that inhibit 90% of the strains tested for these antimicrobial agents with Staphylococcus aureus were 4.0, 0.5, 0.5, 2.0, 1.0, 0.25, 0.5, and 1.0, respectively. The minimum inhibitory concentration values that inhibit 90% of the strains tested against the Staphylococcus spp. ranged from 0.5 to 1.0 for all antimicrobics. The minimum inhibitory concentrations against streptococci were < or = 0.06, 0.5, 0.13, 0.13, 4.0, 1.0, 0.13, and < or = 0.06, respectively. Antimicrobial agents tested against isolates from Denmark included penicillin, ampicillin, oxacillin, cephalothin, ceftiofur, penicillin plus novobiocin, erythromycin, and pirlimycin. Against S. aureus, the minimum inhibitory concentrations were 0.13, 0.5, 0.5, 0.5, 1.0, 0.25, 0.5, and 0.5, respectively. The minimum inhibitory concentrations against Staphylococcus spp. were 0.25, 0.25, 0.5, 0.5, 1.0, < or = 0.06, 0.13, 1.0, and 0.5, respectively. The minimum inhibitory concentrations against the streptococci were < or = 0.06, 0.13, 0.5, 0.5, 1.0, < or = 0.06, 0.13, 0.5, and 0.5, respectively. Minimum inhibitory concentration values for staphylococci from New Zealand and Denmark were similar to values reported for US isolates. Streptococci from New Zealand and Denmark had lower minimum inhibitory concentration values than did US isolates. Only ceftiofur and enrofloxacin were active against the Gram-negative bacilli. PMID:9532511

Salmon, S A; Watts, J L; Aarestrup, F M; Pankey, J W; Yancey, R J

1998-02-01

12

Glycopeptide minimum inhibitory concentration creep among meticillin-resistant Staphylococcus aureus from 2006-2011 in China.  

PubMed

Vancomycin minimum inhibitory concentration (MIC) creep has recently been demonstrated by many countries but is rarely reported in China. In this study, a total of 1411 meticillin-resistant Staphylococcus aureus (MRSA) isolates were collected from six hospitals in China during the period 2006-2011 and the MICs of vancomycin, teicoplanin and linezolid were determined by broth microdilution according to Clinical and Laboratory Standards Institute (CLSI) guidelines. MIC50 and MIC90 values (MICs required to inhibit the growth of 50% and 90% of organisms, respectively) as well as geometric mean (GM) MICs were calculated for all isolates in each year, and MIC creep for the drugs was evaluated. All of the MRSA isolates were susceptible to vancomycin and linezolid. Overall, the vancomycin GM MIC of MRSA isolates was 0.906, 0.952, 0.956, 0.947, 1.013 and 1.040 mg/L, with a significantly increasing trend over the years (P<0.001). Percentages of MRSA isolates with a vancomycin MIC above 1 ?g/mL (2 ?g/mL?MIC>1 ?g/mL) were 26.0%, 23.5%, 21.6%, 27.8%, 30.6% and 42.8% from 2006-2011, respectively, and increased over time (P<0.005). The teicoplanin GM MIC increased rapidly from 0.749 mg/L in 2008 to 0.973 mg/L in 2011, and ca. 5% of isolates were resistant to teicoplanin in the period according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria. MIC shifts were not found for linezolid (P>0.05). In conclusion, a tendency towards decreasing susceptibility to glycopeptides in MRSA has emerged in China. PMID:23562222

Zhuo, Chao; Xu, Ying-chun; Xiao, Shu-nian; Zhang, Guang-yan; Zhong, Nan-Shan

2013-06-01

13

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

SciTech Connect

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.

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

14

Vancomycin Minimum Inhibitory Concentration for Methicillin-Resistant Staphylococcus aureus Infections; Is There Difference in Mortality Between Patients?  

PubMed Central

Background: New data indicates that vancomycin may be less effective against methicillin-resistant Staphylococcus aureus (MRSA) infections with minimum inhibition concentration (MIC) within a sensitive range. Objectives: The aim of this study was to determine the distribution of the vancomycin MIC between MRSA strains and observe the difference in mortality between patients, while the influence of changes in MIC on the efficacy of vancomycin was also examined. Patients and Methods: A routine date-based study was conducted on 41 MRSA isolates in a hospital in Tehran, Iran. The isolates were assessed for MIC by using the E-test method, and results were categorized into three groups: A (MIC < 1.5 ?g/mL), B (1.5 ? MIC < 2 ?g/mL) and C (MIC ? 2 ?g/mL) MRSA. Results: Group A was the most common group, followed by groups C and B. Although there was no statistically significant difference between patients’ mortality with the MIC group, the mortality rate of group A was higher than C and B. Conclusions Regarding Clinical and Laboratory Standards Institute (CLSI) definition for vancomycin susceptibility (MIC < 2 ?g/mL), it seems that vancomycin may not be considered as the best antibiotic in order to treat heteroresistant vancomycin intermediate S. aureus (hVISA) and vancomycin sensitive S. aureus (VSSA) infections, and a new breakpoint for vancomycin and alternative antibiotics should be considered.

Aminzadeh, Zohreh; Yadegarynia, Davood; Fatemi, Alireza; Tahmasebian Dehkordi, Elham; Azad Armaki, Saeed

2014-01-01

15

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

SciTech Connect

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.

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

2011-01-01

16

High vancomycin minimum inhibitory concentration is associated with poor outcome in patients with methicillin-susceptible Staphylococcus aureus bacteremia regardless of treatment.  

PubMed

We retrospectively investigated the impact of high vancomycin minimum inhibitory concentration (MIC > 2 ?g/ml) on the outcome of 53 patients with bacteremia caused by methicillin-susceptible Staphylococcus aureus (MSSA). Vancomycin MIC was determined by broth microdilution according to CLSI methods. The primary outcome was 30-day all-cause mortality from the date of the first positive blood culture. The mortality rate was 22.6% (12 of 53 patients). High vancomycin MIC (odds ratio (OR) = 9.3; 95% confidence interval (95% CI) = 1.31-63.20; p = 0.027), Charlson comorbidity index ? 3 (OR = 10.3; 95% CI = 1.3-102.04; p = 0.03), advanced age (OR = 35.8; 95% CI = 2.3-659.2; p = 0.01), and severe sepsis (OR = 8.5; 95% CI = 1.2-61.4; p = 0.03) were associated with mortality. PMID:25134647

Castón, Juan José; González-Gasca, Francisco; Porras, Lourdes; Illescas, Soledad; Romero, Maria Dolores; Gijón, Julio

2014-11-01

17

Bacterial Resistance Studies Using In Vitro Dynamic Models: the Predictive Power of the Mutant Prevention and Minimum Inhibitory Antibiotic Concentrations  

PubMed Central

In light of the concept of the mutant selection window, i.e., the range between the MIC and the mutant prevention concentration (MPC), MPC-related pharmacokinetic indices should be more predictive of bacterial resistance than the respective MIC-related indices. However, experimental evidence of this hypothesis remains limited and contradictory. To examine the predictive power of the ratios of the area under the curve (AUC24) to the MPC and the MIC, the selection of ciprofloxacin-resistant mutants of four Escherichia coli strains with different MPC/MIC ratios was studied. Each organism was exposed to twice-daily ciprofloxacin for 3 days at AUC24/MIC ratios that provide peak antibiotic concentrations close to the MIC, between the MIC and the MPC, and above the MPC. Resistant E. coli was intensively enriched at AUC24/MPCs from 1 to 10 h (AUC24/MIC from 60 to 360 h) but not at the lower or higher AUC24/MPC and AUC24/MIC ratios. AUC24/MPC and AUC24/MIC relationships of the areas under the time courses of ciprofloxacin-resistant E. coli (AUBCM) were bell-shaped. A Gaussian-like function fits the AUBCM-AUC24/MPC and AUBCM-AUC24/MIC data combined for all organisms (r2 = 0.69 and 0.86, respectively). The predicted anti-mutant AUC24/MPC ratio was 58 ± 35 h, and the respective AUC24/MIC ratio was 1,080 ± 416 h. Although AUC24/MPC was less predictive of strain-independent E. coli resistance than AUC24/MIC, the established anti-mutant AUC24/MPC ratio was closer to values reported for Staphylococcus aureus (60 to 69 h) than the respective AUC24/MIC ratio (1,080 versus 200 to 240 h). This implies that AUC24/MPC might be a better interspecies predictor of bacterial resistance than AUC24/MIC. PMID:23896481

Strukova, Elena N.; Shlykova, Darya S.; Portnoy, Yury A.; Kozyreva, Varvara K.; Edelstein, Mikhail V.; Dovzhenko, Svetlana A.; Kobrin, Mikhail B.; Zinner, Stephen H.

2013-01-01

18

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

PubMed

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; P<0.01, respectively). Antibiotic susceptibility to cotrimoxazole was strongly associated with susceptibility to amoxicillin and nalidixic acid (P<0.01). Community-acquired or healthcare-associated bacteraemia, severity of bacteraemia, and patient outcome were independent of the MICs of ADBAC and DDAC. Our findings demonstrate an epidemiological relationship between higher MIC values of QACs in clinical E. coli isolates and antibiotic resistance. PMID:21807440

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

2011-10-01

19

Effect of Efflux Pump Inhibitor Carbonyl Cyanide 3-Chlorophenylhydrazone on the Minimum Inhibitory Concentration of Ciprofloxacin in Acinetobacter baumannii Clinical Isolates  

PubMed Central

Background: Acinetobacter baumannii is an important human pathogen with increasing notoriety in the recent years, as a causative organism of drug resistant nosocomial infections, particularly in immunocompromised patients hospitalized in burn centers. Objectives: The aim of this study was to determinate the role of efflux pump(s) in ciprofloxacin resistance of A. baumannii strains isolated from burn patients. Materials and Methods: Sixty-five A. baumannii strains were isolated from the burn patients hospitalized in Motahari Burns and Reconstruction Center in Tehran, Iran. Susceptibility test to ciprofloxacin was carried out by disk agar diffusion and agar dilution methods, according to the CLSI guidelines. Activity of the efflux system was evaluated using efflux pump inhibitor carbonyl cyanide 3-chlorophenylhydrazone (CCCP). Results: All Acinetobacter isolates were resistant to ciprofloxacin. The Minimum inhibitory concentration (MIC) range of ciprofloxacin in isolates was 4 to 128 µg/mL or greater. Moreover, susceptibility of strains to ciprofloxacin was highly increased in the presence of efflux pump inhibitor; So that, for 86.1% (56/65) of isolates, CCCP reduced the MIC by 2 to 64 folds. Conclusions: Our findings are suggestive that efflux-based system may play a role in fluoroquinolone resistance in A. baumannii isolates, affecting hospitalized patients. The ability of Acinetobacter to acquire resistance to these potent antimicrobials by the efflux pump mechanism is a concern. Therefore, new strategies are required in order to eliminate the efflux transport activity from the resistant bacteria causing nosocomial infections and provide more appropriate approaches for treatment and management of troubling infections. PMID:25147654

Ardebili, Abdollah; Talebi, Malihe; Azimi, Leila; Rastegar Lari, Abdolaziz

2014-01-01

20

Vancomycin versus daptomycin for the treatment of methicillin-resistant Staphylococcus aureus bacteremia due to isolates with high vancomycin minimum inhibitory concentrations: study protocol for a phase IIB randomized controlled trial  

PubMed Central

Background Vancomycin is the standard first-line treatment for methicillin-resistant Staphylococcus aureus bacteremia. However, recent consensus guidelines recommend that clinicians consider using alternative agents such as daptomycin when the vancomycin minimum inhibitory concentration is greater than 1 ug/ml. To date however, there have been no head-to-head randomized trials comparing the safety and efficacy of daptomycin and vancomycin in the treatment of such infections. The primary aim of our study is to compare the efficacy of daptomycin versus vancomycin in the treatment of bloodstream infections due to methicillin-resistant Staphylococcus aureus isolates with high vancomycin minimum inhibitory concentrations (greater than or equal to 1.5 ug/ml) in terms of reducing all-cause 60-day mortality. Methods/Design The study is designed as a multicenter prospective open label phase IIB pilot randomized controlled trial. Eligible participants will be inpatients over 21-years-old with a positive blood culture for methicillin-resistant Staphylococcus aureus with vancomycin minimum inhibitory concentration of greater than or equal to 1.5ug/ml. Randomization into intervention or active control arms will be performed with a 1:1 allocation ratio. We aim to recruit 50 participants over a period of two years. Participants randomized to the active control arm will receive vancomycin dose-while those randomized to the intervention arm will receive daptomycin. Participants will receive a minimum of 14 days study treatment. The primary analysis will be conducted on the intention-to-treat principle. The Fisher’s exact test will be used to compare the 60-day mortality rate from index blood cultures (primary endpoint) between the two treatment arms, and the exact two-sided 95% confidence interval will be calculated using the Clopper and Pearson method. Primary analysis will be conducted using a two sided alpha of 0.05. Discussion If results from this pilot study suggest that daptomycin shows significant efficacy in the treatment of bloodstream infections due to methicillin-resistant Staphylococcus aureus isolates with high vancomycin minimum inhibitory concentrations, we aim to proceed with a larger scale confirmatory study. This would help guide clinicians and inform practice guidelines on the optimal treatment for such infections. Trial registration The trial is listed on clinicaltrials.gov (NCT01975662, date of registration: 29 October 2013). PMID:24943129

2014-01-01

21

Comparison of minimum inhibitory concentration of water soluble extracts of eugenia jambolana lam. (Fam. Myrtaceae) barks of different ages on dysentery and diarrhoea forming micro - organisms.  

PubMed

A preliminary investigations was carried out to study the antibacterial activity of the water soluble extracts of five and ten years old barks of Eugenia Jambolana Lam. (fam. Myrtaceae) on dysentery and diarrhoea forming micro organisms. It was observed that the barks of young plants have a better inhibitory effect on micro - organisms like Salmonella viballerup, Shigella dysenteriae 10, Shigella boydii 5, Sgigella dysenteriae 2. PMID:22557509

Maiti, A P; Pal, S C; Chattopadhyay, D; De, S; Nandy, A

1985-10-01

22

Flammability limits of dusts: Minimum inerting concentrations  

SciTech Connect

A new flammability limit parameter has been defined as the Minimum Inerting Concentration (MIC). This is the concentration of inertant required to prevent a dust explosion regardless of fuel concentration. Previous experimental work at Fike in a 1-m{sup 3} spherical chamber has shown this flammability limit to exist for pulverized coal dust and cornstarch. In the current work, inerting experiments with aluminum, anthraquinone and polyethylene dusts as fuels were performed, using monoammonium phosphate and sodium bicarbonate as inertants. The results show that an MIC exists only for anthraquinone inerted with sodium bicarbonate. The other combustible dust and inertant mixtures did not show a definitive MIC, although they did show a strong dependence between inerting level and suspended fuel concentration. As the fuel concentration increased, the amount of inertant required to prevent an explosion decreased. Even though a definitive MIC was not found for most of the dusts an effective MIC can be estimated from the data. The use of MIC data can aid in the design of explosion suppression schemes.

Dastidar, A.G.; Amyotte, P.R. [Dalhousie Univ., Halifax, Nova Scotia (Canada). Dept. of Chemical Engineering] [Dalhousie Univ., Halifax, Nova Scotia (Canada). Dept. of Chemical Engineering; Going, J.; Chatrathi, K. [Fike Corp., Blue Springs, MO (United States)] [Fike Corp., Blue Springs, MO (United States)

1999-05-01

23

Recovery of alicyclobacillus from inhibitory fruit juice concentrates.  

PubMed

Growth of Alicyclobacillus in low-pH fruit juices may result in off-odors and off-flavors due to the production of compounds such as guaiacol (2-methoxy phenol). An important step in preventing Alicyclobacillus contamination of fruit juices is the screening of incoming ingredients. Many fruit juice concentrates contain compounds that inhibit Alicyclobacillus growth, but beverages produced from the concentrates may not contain sufficient amounts of the active component to prevent spoilage. Therefore, accurate screening of juice concentrates is essential to prevent false-negative test results and product spoilage. The objective of this study was to evaluate isolation methods for detection of Alicyclobacillus in inhibitory juice concentrates. Recovery of Alicyclobacillus spores from inoculated and naturally contaminated concentrates was compared by using pour plate, spread plate, and filtration methods. Pour plates consistently recovered the lowest number of spores from inoculated concentrates. Spread plating was the most effective method used to recover spores from inoculated apple and pomegranate juice concentrates, while filtration resulted in the highest recovery from cranberry concentrate. When tested on naturally contaminated concentrates, the pour plate method failed to detect Alicyclobacillus in many samples. Filtration was much more effective. The filtration method increased the likelihood of detecting Alicyclobacillus contamination of fruit juice concentrates containing inhibitory compounds. PMID:21819669

McNamara, Christopher J; Wiebe, Deborah; Gomez, Margarita

2011-08-01

24

6 CFR 27.204 - Minimum concentration by security issue.  

Code of Federal Regulations, 2012 CFR

...commercial grades of the chemical at the specified minimum concentration. (c) Sabotage and Contamination Chemicals. For each sabotage/contamination chemical of interest, a facility shall count the total quantity of all commercial grades of...

2012-01-01

25

6 CFR 27.204 - Minimum concentration by security issue.  

...commercial grades of the chemical at the specified minimum concentration. (c) Sabotage and Contamination Chemicals. For each sabotage/contamination chemical of interest, a facility shall count the total quantity of all commercial grades of...

2014-01-01

26

6 CFR 27.204 - Minimum concentration by security issue.  

Code of Federal Regulations, 2013 CFR

...commercial grades of the chemical at the specified minimum concentration. (c) Sabotage and Contamination Chemicals. For each sabotage/contamination chemical of interest, a facility shall count the total quantity of all commercial grades of...

2013-01-01

27

Agar and broth dilution methods to determine the minimal inhibitory concentration (MIC) of antimicrobial substances  

Microsoft Academic Search

The aim of broth and agar dilution methods is to determine the lowest concentration of the assayed antimicrobial agent (minimal inhibitory concentration, MIC) that, under defined test conditions, inhibits the visible growth of the bacterium being investigated. MIC values are used to determine susceptibilities of bacteria to drugs and also to evaluate the activity of new antimicrobial agents. Agar dilution

Irith Wiegand; Kai Hilpert; Robert E W Hancock

2008-01-01

28

Wild-type minimal inhibitory concentration distributions in bacteria of animal origin in Argentina.  

PubMed

The aim of this study was to determine the antimicrobial resistance profiles of indicator bacteria isolated from domestic animal feces. Minimal inhibitory concentration (MIC) was determined by agar dilution. Interpretative criteria on the basis of wild-type MIC distributions and epidemiological cutoff values (ECOFF or ECV) were used according to the 'European Committee on Antimicrobial Susceptibility Testing' (EUCAST) data. Results from 237 isolates of Escherichia coli showed reduced susceptibility for ampicillin, streptomycin and tetracycline, the antimicrobials commonly used in intensive breeding of pigs and hens. Regarding all the species of the genus Enterococcus spp., there are only ECOFF or ECV for vancomycin. Of the 173 Enterococcus spp. isolated, only one showed reduced susceptibility to vancomycin and was classified as 'non-wild-type' (NWT) population. This is the first report in Argentina showing data of epidemiological cutoff values in animal bacteria. PMID:24721272

Pantozzi, Florencia L; Ibar, Mariela P; Nievas, Victorio F; Vigo, Germán B; Moredo, Fabiana A; Giacoboni, Gabriela I

2014-01-01

29

The influence of subminimal inhibitory concentrations of benzalkonium chloride on biofilm formation by Listeria monocytogenes.  

PubMed

Disinfectants, such as benzalkonium chloride (BAC), are commonly used to control Listeria monocytogenes and other pathogens in food processing plants. Prior studies have demonstrated that the resistance to BAC of L. monocytogenes was associated with the prolonged survival of three strains of molecular serotype 1/2a in an Iberian pork processing plant. Because survival in such environments is related to biofilm formation, we hypothesised that the influence of BAC on the biofilm formation potential of L. monocytogenes might differ between BAC-resistant strains (BAC-R, MIC?10mg/L) and BAC-sensitive strains (BAC-S, MIC?2.5mg/L). To evaluate this possibility, three BAC-R strains and eight BAC-S strains, which represented all of the molecular serotype 1/2a strains detected in the sampled plant, were compared. Biofilm production was measured using the crystal violet staining method in 96-well microtitre plates. The BAC-R strains produced significantly (p<0.05) less biofilm than the BAC-S in the absence of BAC, independent of the rate of planktonic growth. In contrast, when the biofilm values were measured in the presence of BAC, one BAC-R strain (S10-1) was able to form biofilm at 5mg/L of BAC, which prevented biofilm formation among the rest of the strains. A genetic determinant of BAC resistance recently described in L. monocytogenes (Tn6188) was detected in S10-1. When a BAC-S strain and its spontaneous mutant BAC-R derivative were compared, resistance to BAC led to biofilm formation at 5mg/L of BAC and to a significant (p<0.05) stimulation of biofilm formation at 1.25mg/L of BAC, which significantly (p<0.05) reduced the biofilm level in the parent BAC-S strain. Our results suggest that the effect of subminimal inhibitory concentrations of BAC on biofilm production by L. monocytogenes might differ between strains with different MICs and even between resistant strains with similar MICs but different genetic determinants of BAC resistance. For BAC-R strains similar to S10-1, subminimal inhibitory BAC may represent an advantage, compensating for the weak biofilm formation level that might be associated with resistance. Biofilm formation in the presence of increased subminimal inhibitory concentrations of the disinfectant may represent an important attribute among certain resistant and persistent strains of L. monocytogenes. PMID:25136789

Ortiz, Sagrario; López, Victoria; Martínez-Suárez, Joaquín V

2014-10-17

30

Minimum detectable concentration as a function of gamma walkover survey technique.  

PubMed

Gamma walkover surveys are often performed by swinging the radiation detector (e.g., a 2-inch by 2-inch sodium iodide) in a serpentine pattern at a near constant height above the ground surface. The objective is to survey an approximate 1-m swath with 100% coverage producing an equal probability of detecting contamination at any point along the swing. In reality, however, the detector height will vary slightly along the swing path, and in some cases the detector may follow a pendulum-like motion significantly reducing the detector response and increasing the minimum detectable concentration. This paper quantifies relative detector responses for fixed and variable height swing patterns and demonstrates negative impacts on the minimum detectable concentration. Minimum detectable concentrations are calculated for multiple contaminated surface areas (0.1, 1.0, 3, 10, and 30 m2), multiple contaminants (60Co, 137Cs, 241Am, and 226Ra), and two minimum heights (5 and 10 cm). Exposure rate estimates used in minimum detectable concentration calculations are produced using MicroShield™ v.7.02 (Grove Software, Inc., 4925 Boonsboro Road #257, Lynchberg, VA 24503) and MDCs are calculated as outlined in NUREG-1575. Results confirm a pendulum-like detector motion can significantly increase MDCs relative to a low flat trajectory, especially for small areas of elevated activity--up to a 47% difference is observed under worst-modeled conditions. PMID:22249469

King, David A; Altic, Nickolas; Greer, Colt

2012-02-01

31

Increases in Spinal Cerebrospinal Fluid Potassium Concentration Do Not Increase Isoflurane Minimum Alveolar Concentration in Rats  

PubMed Central

BACKGROUND Previous studies demonstrated that MAC for isoflurane directly correlates with the concentration of Na+ in cerebrospinal fluid surrounding the spinal cord, the primary site for mediation of the immobility produced by inhaled anesthetics. If this correlation resulted from increased irritability of the cord, then infusion of increased concentrations of potassium (K+) might be predicted to act similarly. However, an absence of effect of K+ might be interpreted to indicate that K+ channels do not mediate the immobility produced by inhaled anesthetics whereas Na+ channels remain as potential mediators. Accordingly, in the present study, we examined the effect of altering intrathecal concentrations of K+ on MAC. METHODS In rats prepared with chronic indwelling intrathecal catheters, we infused solutions deficient in K+ and with an excess of K+ into the lumbar space and measured MAC for isoflurane 24 h before, during, and 24 h after infusion. Rats similarly prepared were tested for the effect of altered osmolarity on MAC (accomplished by infusion of mannitol) and for the penetration of Na+ into the cord. RESULTS MAC of isoflurane never significantly increased with increasing concentrations of K+ infused intrathecally. At infused concentrations exceeding 12 times the normal concentration of KCl, i.e., 29 mEq/L, rats moved spontaneously at isoflurane concentrations just below, and sometimes at MAC, but the average MAC in these rats did not exceed their control MAC. At the largest infused concentration (58.1 mEq/L), MAC significantly decreased and did not subsequently return to normal (i.e., such large concentrations produced injury). Infusions of lower concentrations of K+ had no effect on MAC. Infusion of osmotically equivalent solutions of mannitol did not affect MAC. Na+ infused intrathecally measurably penetrated the spinal cord. CONCLUSIONS The results do not support a mediation or modulation of MAC by K+ channels. PMID:18713900

Shnayderman, Dimitry; Laster, Michael J.; Eger, Edmond I; Oh, Irene; Zhang, Yi; Jinks, Steven L.; Antognini, Joseph F.; Raines, Douglas E.

2009-01-01

32

Inhaled Anesthetics Do Not Combine to Produce Synergistic Effects Regarding Minimum Alveolar Anesthetic Concentration in Rats  

Microsoft Academic Search

BACKGROUND: We hypothesized that pairs of inhaled anesthetics having divergent potencies (one acting weakly at minimum alveolar anesthetic concentration (MAC); one acting strongly at MAC) on specific receptors\\/channels might act synergisti- cally, and that such deviations from additivity would support the notion that anesthetics act on multiple sites to produce anesthesia. METHODS: Accordingly, we studied the additivity of MAC for

Edmond I Eger II; Michael Tang; Mark Liao; Michael J. Laster; Ken Solt; Pamela Flood; Andrew Jenkins; Douglas Raines; Jan F. Hendrickx; Steven L. Shafer; Tanifuji Yasumasa; James M. Sonner

2008-01-01

33

BME BIOMEDICAL IMAGING CONCENTRATION F12 MS: 30 total credit hours minimum  

E-print Network

BME BIOMEDICAL IMAGING CONCENTRATION ­ F12 MS: 30 total credit hours minimum Advisor: Luis Hernandez-Garcia, Ph.D. (hernan@umich.edu) Biomedical Imaging: BIOMEDE 5161 Medical Imaging Systems (3) (I)2): BIOMEDE 458 Biomedical Instrumentation and Design (4) (I,II) BIOMEDE 510 Medical Imaging Laboratory (3

Kamat, Vineet R.

34

BME BIOMEDICAL IMAGING CONCENTRATION F10 MS: 30 total credit hours minimum  

E-print Network

BME BIOMEDICAL IMAGING CONCENTRATION ­ F10 MS: 30 total credit hours minimum Advisor: Luis Hernandez-Garcia, Ph.D. (hernan@umich.edu) Biomedical Imaging: BIOMED E 5161 Medical Imaging Systems (3) (I): BIOMED E 458 Biomedical Instrumentation and Design (4) (I,II) BIOMED E 510 Medical Imaging Laboratory (3

Eustice, Ryan

35

BME BIOMEDICAL IMAGING CONCENTRATION F11 MS: 30 total credit hours minimum  

E-print Network

BME BIOMEDICAL IMAGING CONCENTRATION ­ F11 MS: 30 total credit hours minimum Advisor: Luis Hernandez-Garcia, Ph.D. (hernan@umich.edu) Biomedical Imaging: BIOMEDE 5161 Medical Imaging Systems (3) (I)2): BIOMEDE 458 Biomedical Instrumentation and Design (4) (I,II) BIOMEDE 510 Medical Imaging Laboratory (3

Eustice, Ryan

36

BME BIOTECHNOLOGY CONCENTRATION F12 MS: 30 total credit hours minimum  

E-print Network

BME BIOTECHNOLOGY CONCENTRATION ­ F12 MS: 30 total credit hours minimum Advisor: Michael Mayer, Ph.D. (mimayer@umich.edu) Biotechnology (one course): BIOMEDE 410 Design and Application of Biomaterials (3) (l)1 of Engineering): One course from this list: BIOLCHEM 515 Introductory Biochemistry (Biotechnology only)5 (3) (I

Kamat, Vineet R.

37

BME BIOTECHNOLOGY CONCENTRATION F10 MS: 30 total credit hours minimum  

E-print Network

BME BIOTECHNOLOGY CONCENTRATION ­ F10 MS: 30 total credit hours minimum Students last name begins: Michael Mayer, Ph.D. (mimayer@umich.edu) Biotechnology (one course): BIOMED E 410 Design and Application (Biotechnology only)5 (3) (I, II) BIOMED E 519 Quantitative Physiology (Tissue Engineering only)6 (4) (I) Other

Eustice, Ryan

38

BME BIOTECHNOLOGY CONCENTRATION F11 MS: 30 total credit hours minimum  

E-print Network

BME BIOTECHNOLOGY CONCENTRATION ­ F11 MS: 30 total credit hours minimum Students last name begins: Michael Mayer, Ph.D. (mimayer@umich.edu) Biotechnology (one course): BIOMEDE 410 Design and Application of Engineering): At least one of the following: BIOLCHEM 515 Introductory Biochemistry (Biotechnology only)5 (3

Eustice, Ryan

39

Comparison of stress concentration versus minimum solid area based mechanical property-porosity relations  

Microsoft Academic Search

Stress concentrations due to pore shape are questioned as a fundamental determinant of mechanical property-porosity relations, especially elastic property porosity relations. On the other hand, actual solid load-bearing areas, especially minimum solid areas of porous bodies, clearly are a determinant of mechanical property-porosity effects. The correlation of pore shape-stress concentration effects with elastic properties of ceramics can be explained by

R. W. Rice; W. R. Grace

1993-01-01

40

Sub-Inhibitory Concentrations of Trans-Cinnamaldehyde Attenuate Virulence in Cronobacter sakazakii in Vitro  

PubMed Central

Cronobacter sakazakii is a foodborne pathogen, which causes a life-threatening form of meningitis, necrotizing colitis and meningoencephalitis in neonates and children. Epidemiological studies implicate dried infant formula as the principal source of C. sakazakii. In this study, we investigated the efficacy of sub-inhibitory concentrations (SIC) of trans-cinnamaldehyde (TC), an ingredient in cinnamon, for reducing C. sakazakii virulence in vitro using cell culture, microscopy and gene expression assays. TC significantly (p ? 0.05) suppressed C. sakazakii adhesion to and invasion of human and rat intestinal epithelial cells, and human brain microvascular endothelial cells. In addition, TC inhibited C. sakazakii survival and replication in human macrophages. We also observed that TC reduced the ability of C. sakazakii to cause cell death in rat intestinal cells, by inhibiting nitric oxide production. Results from gene expression studies revealed that TC significantly downregulated the virulence genes critical for motility, host tissue adhesion and invasion, macrophage survival, and LPS (Lipopolysaccharide) synthesis in C. sakazakii. The efficacy of TC in attenuating these major virulence factors in C. sakazakii underscores its potential use in the prevention and/or control of infection caused by this pathogen. PMID:24837831

Amalaradjou, Mary Anne Roshni; Kim, Kwang Sik; Venkitanarayanan, Kumar

2014-01-01

41

Sub-inhibitory concentrations of trans-cinnamaldehyde attenuate virulence in Cronobacter sakazakii in vitro.  

PubMed

Cronobacter sakazakii is a foodborne pathogen, which causes a life-threatening form of meningitis, necrotizing colitis and meningoencephalitis in neonates and children. Epidemiological studies implicate dried infant formula as the principal source of C. sakazakii. In this study, we investigated the efficacy of sub-inhibitory concentrations (SIC) of trans-cinnamaldehyde (TC), an ingredient in cinnamon, for reducing C. sakazakii virulence in vitro using cell culture, microscopy and gene expression assays. TC significantly (p ? 0.05) suppressed C. sakazakii adhesion to and invasion of human and rat intestinal epithelial cells, and human brain microvascular endothelial cells. In addition, TC inhibited C. sakazakii survival and replication in human macrophages. We also observed that TC reduced the ability of C. sakazakii to cause cell death in rat intestinal cells, by inhibiting nitric oxide production. Results from gene expression studies revealed that TC significantly downregulated the virulence genes critical for motility, host tissue adhesion and invasion, macrophage survival, and LPS (Lipopolysaccharide) synthesis in C. sakazakii. The efficacy of TC in attenuating these major virulence factors in C. sakazakii underscores its potential use in the prevention and/or control of infection caused by this pathogen. PMID:24837831

Amalaradjou, Mary Anne Roshni; Kim, Kwang Sik; Venkitanarayanan, Kumar

2014-01-01

42

Sub-inhibitory concentration of biogenic selenium nanoparticles lacks post antifungal effect for Aspergillus niger and Candida albicans and stimulates the growth of Aspergillus niger  

PubMed Central

Background The antifungal activity of selenium nanoparticles (Se NPs) prepared by Klebsiella pneumoniae has been reported previously for different fungi. In the present study, freshly prepared Se NPs produced by K. pneumoniae were purified and characterized by transmission electron microscopy and Energy-Dispersive X-ray spectroscopy (EDS) and its post antifungal effects for two fungi were evaluated. Materials and Methods The minimum inhibitory concentrations (MICs) of Se NPs, determined by serial dilution were 250 µg/ml for Aspergillus niger and 2,000 µg/ml for Candida albicans. The effect of exposure of A. niger and C. albicans to Se NPs on later growth was evaluated by incubating the fungi for 1 hour at 25 °C in media containing 0, 1, 2 and 4 x MIC of Se NPs and diluting the cultures 100 times with Se free medium. The kinetics of growth of the fungi in control cultures and in non-toxic Se NPs concentration of, 0.01 × MIC, 0.02 × MIC or 0.04 × MIC were measured. Results The exposure of A. niger and C. albicans to 2 and 4 x MIC of Se NPs stimulated the growth of both fungi in the absence of toxic concentrations of Se. The strongest stimulation was observed for A. niger. Conclusion It is concluded that exposure to high concentration of the Se NPs did not have any post-inhibitory effect on A. niger and C. albicans and that trace amounts of this element promoted growth of both fungi in a dose- dependent-manner. The role of nanoparticles serving as needed trace elements and development of microorganism tolerance to nanoparticles should not be dismissed while considering therapeutic potential. PMID:23466957

Kazempour, Zahra Bahri; Yazdi, Mohammad Hossein; Rafii, Fatemeh; Shahverdi, Ahmad Reza

2013-01-01

43

Technical basis for a minimum hydroxide concentration in tanks containing dilute waste  

SciTech Connect

Laboratory tests were performed to address the protection of waste tank steel from corrosion in situations of elevated temperatures up to 75 C (hot spots) in the sludge layer of Extended Sludge Processing (ESP) tanks. Coupon immersion tests were conducted at 75 C in two ESP simulants at four hydroxide (or pH) levels. The nitrite concentrations of the simulants were calculated from the ESP technical standards based on a temperature of 40 C. The results showed that a hydroxide concentration of at least 0.01 M prevented significant corrosion of the steel at the elevated temperature. This conclusion provides the technical basis for the revised minimum hydroxide concentration of 0.01 M in the draft WSRC 241-82H Control Room Process Requirements, for the ESP tanks.

Zapp, P.E.

1995-05-01

44

Effect of cigarette smoke on human serum trypsin inhibitory capacity and antitrypsin concentration  

SciTech Connect

Investigation of the effect of cigarette smoke on the serum trypsin inhibitory capacity (TIC) and antitrypsin content in 89 smokers compared with 37 nonsmokers revealed that cigarette smoking is associated with a significantly lower level of TIC. No alteration in serum antitrypsin content was found because of cigarette smoking. Further analysis of the data indicated a correlation between the magnitude of smoking and the reduction in serum TIC. The reduction of TIC in cigarette smokers is consistent with the recent findings of decreased alpha 1-antitrypsin activity in rat lung and the reduced elastase inhibitory capacity per mg of alpha 1-antitrypsin found in the serum of smokers. The decrease in TIC in the serum of smokers, in addition to the reported decrease in elastolytic activity, may be useful in explaining the pathogenesis of emphysema frequently found in smokers.

Chowdhury, P.; Bone, R.C.; Louria, D.B.; Rayford, P.L.

1982-07-01

45

Effects of fentanyl on isoflurane minimum alveolar concentration in New Zealand White rabbits (Oryctolagus cuniculus).  

PubMed

OBJECTIVE To determine effects of increasing plasma fentanyl concentrations on the minimum alveolar concentration (MAC) of isoflurane in rabbits. ANIMALS 6 adult female New Zealand White rabbits (Oryctolagus cuniculus). PROCEDURES Rabbits were anesthetized with isoflurane in oxygen; ventilation was controlled and body temperature maintained between 38.5° and 39.5°C. Fentanyl was administered IV by use of a computer-controlled infusion system to achieve 6 target plasma concentrations. Isoflurane MAC was determined in duplicate by use of the bracketing technique with a supramaximal electrical stimulus. Blood samples were collected for measurement of plasma fentanyl concentration at each MAC determination. The MAC values were analyzed with a repeated-measures ANOVA followed by Holm-Sidak pairwise comparisons. RESULTS Mean ± SD plasma fentanyl concentrations were 0 ± 0 ng/mL (baseline), 1.2 ± 0.1 ng/mL, 2.2 ± 0.3 ng/mL, 4.4 ± 0.4 ng/mL, 9.2 ± 0.4 ng/mL, 17.5 ± 2.6 ng/mL, and 36.8 ± 2.4 ng/mL. Corresponding mean values for isoflurane MAC were 1.92 ± 0.16%, 1.80 ± 0.16%, 1.60 ± 0.23%, 1.46 ± 0.22%, 1.12 ± 0.19%, 0.89 ± 0.14%, and 0.70 ± 0.15%, respectively. Isoflurane MAC for plasma fentanyl concentrations ? 2.2 ng/mL differed significantly from the baseline value. In 3 rabbits, excessive spontaneous movement prevented MAC determination at the highest plasma fentanyl concentration. CONCLUSIONS AND CLINICAL RELEVANCE Fentanyl reduced isoflurane MAC by approximately 60% in New Zealand White rabbits. Further studies will be needed to investigate the cardiorespiratory effects of isoflurane and fentanyl combinations in rabbits; however, fentanyl may prove to be a useful adjunct to inhalation anesthesia in this species. PMID:25629907

Barter, Linda S; Hawkins, Michelle G; Pypendop, Bruno H

2015-02-01

46

Estimation of minimum detectable concentration of chlorine in the blast furnace slag cement concrete  

NASA Astrophysics Data System (ADS)

The Prompt Gamma Neutron Activation Analysis technique was used to measure the concentration of chloride in the blast furnace slag (BFS) cement concrete to assess the possibility of reinforcement corrosion. The experimental setup was optimized using Monte Carlo calculations. The BFS concrete specimens containing 0.8-3.5 wt.% chloride were prepared and the concentration of chlorine was evaluated by determining the yield of 6.11, 6.62, 7.41, 7.79 and 8.58 MeV gamma-rays. The Minimum Detectable Concentration (MDC) of chlorine in the BFS cement concrete was estimated. The best value of MDC limit of chlorine in the BFS cement concrete was found to be 0.034 ± 0.011 and 0.038 ± 0.012 wt.% for 6.11 and 6.62 MeV prompt gamma-rays. Within the statistical uncertainty the lower bound of the measured MDC of chlorine in the BFS cement concrete meets the maximum permissible limit of 0.03 wt.% of chloride set by the American Concrete Institute.

Naqvi, A. A.; Maslehuddin, M.; Garwan, M. A.; Nagadi, M. M.; Al-Amoudi, O. S. B.; Khateeb-ur-Rehman; Raashid, M.

2011-01-01

47

Inhaled anesthetics and immobility: mechanisms, mysteries, and minimum alveolar anesthetic concentration.  

PubMed

Studies using molecular modeling, genetic engineering, neurophysiology/pharmacology, and whole animals have advanced our understanding of where and how inhaled anesthetics act to produce immobility (minimum alveolar anesthetic concentration; MAC) by actions on the spinal cord. Numerous ligand- and voltage-gated channels might plausibly mediate MAC, and specific amino acid sites in certain receptors present likely candidates for mediation. However, in vivo studies to date suggest that several channels or receptors may not be mediators (e.g., gamma-aminobutyric acid A, acetylcholine, potassium, 5-hydroxytryptamine-3, opioids, and alpha(2)-adrenergic), whereas other receptors/channels (e.g., glycine, N-methyl-D-aspartate, and sodium) remain credible candidates. PMID:12933393

Sonner, James M; Antognini, Joseph F; Dutton, Robert C; Flood, Pamela; Gray, Andrew T; Harris, R Adron; Homanics, Gregg E; Kendig, Joan; Orser, Beverley; Raines, Douglas E; Rampil, Ira J; Trudell, James; Vissel, Bryce; Eger, Edmond I

2003-09-01

48

Extracellular Hsp72 concentration relates to a minimum endogenous criteria during acute exercise-heat exposure.  

PubMed

Extracellular heat shock protein 72 (eHsp72) concentration increases during exercise-heat stress when conditions elicit physiological strain. Differences in severity of environmental and exercise stimuli have elicited varied response to stress. The present study aimed to quantify the extent of increased eHsp72 with increased exogenous heat stress, and determine related endogenous markers of strain in an exercise-heat model. Ten males cycled for 90 min at 50 % [Formula: see text] in three conditions (TEMP, 20 °C/63 % RH; HOT, 30.2 °C/51%RH; VHOT, 40.0 °C/37%RH). Plasma was analysed for eHsp72 pre, immediately post and 24-h post each trial utilising a commercially available ELISA. Increased eHsp72 concentration was observed post VHOT trial (+172.4 %) (p < 0.05), but not TEMP (-1.9 %) or HOT (+25.7 %) conditions. eHsp72 returned to baseline values within 24 h in all conditions. Changes were observed in rectal temperature (Trec), rate of Trec increase, area under the curve for Trec of 38.5 and 39.0 °C, duration Trec??38.5 and ?39.0 °C, and change in muscle temperature, between VHOT, and TEMP and HOT, but not between TEMP and HOT. Each condition also elicited significantly increasing physiological strain, described by sweat rate, heart rate, physiological strain index, rating of perceived exertion and thermal sensation. Stepwise multiple regression reported rate of Trec increase and change in Trec to be predictors of increased eHsp72 concentration. Data suggests eHsp72 concentration increases once systemic temperature and sympathetic activity exceeds a minimum endogenous criteria elicited during VHOT conditions and is likely to be modulated by large, rapid changes in core temperature. PMID:24085588

Gibson, Oliver R; Dennis, Alex; Parfitt, Tony; Taylor, Lee; Watt, Peter W; Maxwell, Neil S

2014-05-01

49

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

SciTech Connect

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 ?M TCS), but not with low-concentration treatments (? 2.5 ?M TCS). TCS inhibited adipocyte differentiation of hMSCs in a concentration-dependent manner in the 0.156 to 2.5 ?M 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 ?M. ? TCS at concentrations ? 2.5 ?M 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.

Guo, Li-Wu [Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States)] [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)] [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)] [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)] [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)] [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)] [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)] [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)] [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)] [Division of Personalized Nutrition and Medicine, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States)

2012-07-15

50

Inadequate vancomycin therapy in term and preterm neonates: a retrospective analysis of trough serum concentrations in relation to minimal inhibitory concentrations  

PubMed Central

Background Vancomycin is effective against gram-positive bacteria and the first-line antibiotic for treatment of proven coagulase-negative staphylococcal infections. The aim of this study is bipartite: first, to assess the percentage of therapeutic initial trough serum concentrations and second, to evaluate the adequacy of the therapeutic range in interrelationship with the observed MIC-values in neonates. Methods In this study, preterm and term neonates admitted at a tertiary NICU in the Netherlands from January 2009 to December 2012 and treated with vancomycin for a proven gram-positive infection were included. Trough serum concentrations were measured prior to administration of the 5th dose. Trough concentrations in the range of 10 to 15 mg/L were considered therapeutic. Staphylococcal species minimal inhibitory concentrations (MIC’s) were determined using the E-test method. Species identification was performed by matrix-assisted laser desorption/ionisation mass spectrometry. Results Of the 112 neonates, 53 neonates (47%) had sub-therapeutic initial trough serum concentrations of vancomycin, whereas 22% had supra-therapeutic initial trough serum concentrations. In all patients doses were adjusted on basis of the initial trough concentration. In 40% (23/57) of the neonates the second trough concentration remained sub-therapeutic. MIC’s were determined for 30 coagulase-negative Staphylococcus isolates obtained from 19 patients. Only 4 out of 19 subjects had a trough concentration greater than tenfold the MIC. Conclusions Forty-seven percent of the neonates had sub-therapeutic initial trough serum concentrations of vancomycin. The MIC-data indicate that the percentages of underdosed patients may be greater. It may be advisable to increase the lower limit of the therapeutic range for European neonates. PMID:25066951

2014-01-01

51

Dipeptidyl peptidase-IV inhibitory peptides generated by tryptic hydrolysis of a whey protein concentrate rich in ?-lactoglobulin.  

PubMed

Dipeptidyl peptidase-IV (DPP-IV) is a serine protease involved in the degradation and inactivation of incretin hormones that act by stimulating glucose-dependent insulin secretion after meal ingestion. DPP-IV inhibitors have emerged as new and promising oral agents for the treatment of type 2 diabetes. The purpose of this study was to investigate the potential of ?-lactoglobulin as natural source of DPP-IV inhibitory peptides. A whey protein concentrate rich in ?-lactoglobulin was hydrolysed with trypsin and fractionated using a chromatographic separation at semipreparative scale. Two of the six collected fractions showed notable DPP-IV inhibitory activity. These fractions were analysed by HPLC coupled to tandem mass spectrometry (HPLC-MS/MS) to identify peptides responsible for the observed activity. The most potent fragment (IPAVF) corresponded to ?-lactoglobulin f(78-82) which IC50 value was 44.7?M. The results suggest that peptides derived from ?-lactoglobulin would be beneficial ingredients of foods against type 2 diabetes. PMID:23790888

Silveira, Silvana T; Martínez-Maqueda, Daniel; Recio, Isidra; Hernández-Ledesma, Blanca

2013-11-15

52

Brainstem Regions Affecting Minimum Alveolar Concentration and Movement Pattern during Isoflurane Anesthesia  

PubMed Central

Background Spinal transection or selective delivery of volatile anesthetics to the spinal cord reduces minimum alveolar concentration (MAC), whereas precollicular decerebration does not. The authors sought to determine which brainstem regions influence anesthetic requirements and movement responses with isoflurane. Methods Movement (biceps femoris electromyogram) and MAC were measured in adult rats before and after decerebration at the precollicular, mid-collicular, pontine or medullary level, or decerebellation. Additional experiments assessed the effects of lidocaine inactivation of the mesencephalic locomotor region on MAC and the effects of isoflurane on nociceptive neuronal responses in this region. Results Transections placed at the level of the mid-colliculus, rostral pons, and pontomedullary junction significantly reduced MAC by approximately 10, 40, and 45%, respectively. MAC was decreased 9% after mid-medullary transections that were placed caudal to the nucleus raphe magnus but rostral to the dorsal reticular nucleus; however, only weak, single movements occurred. Caudal medullary transections at the obex decreased MAC by 60%. Bilateral inactivation of the mesencephalic locomotor region with lidocaine caused a reversible, 32% decrease in MAC and reduced the number and amplitude of movements at sub-MAC isoflurane concentrations. Neuronal responses of mesencephalic locomotor region neurons to supramaximal noxious tail clamp were reduced by 87% by 1.2 MAC isoflurane. Conclusions The authors conclude that the mesencephalic locomotor region influences anesthetic requirements and promotes repetitive movement with sub-MAC isoflurane by facilitating ventral spinal locomotor circuits, where anesthetics seem to exert their key immobilizing effects. However, net brainstem influences on MAC seem to result from interaction among descending nociceptive and locomotor modulatory pathways. PMID:20098133

Jinks, Steven L.; Bravo, Milo; Satter, Omar; Chan, Yuet-Ming

2010-01-01

53

Inhibitory effect of post-micellar SDS concentration on thermal aggregation and activity of papain.  

PubMed

Papain, a cysteine protease isolated from the latex of Carica papaya, is known to undergo irreversible thermal unfolding. In this study, we found that thermal unfolding of papain is accompanied by a simultaneous self-assembly process where this protein is observed to aggregate above 50°C. The extent of aggregation increased with increasing protein concentration from 3-40 µM. The aggregation was confirmed by enhanced turbidity, light scattering intensity, 1-anilino-8-naphthalene sulfonate (ANS) fluorescence intensity and by transmission electron microscopy. Furthermore, we noted that post-micellar concentration of sodium dodecyl sulfate (SDS) remarkably suppresses the thermal aggregation of papain. Far-UV circular dichroism studies revealed that SDS significantly enhances ?-helical content of the protein and also tends to prevent its unfolding, and thus inhibits aggregation. Additionally, papain showed maximal activity at 65°C in neutral buffer. However, in the presence of 6 mM SDS (above its critical micellar concentration), the enzyme lost activity by about 10-fold. Thus, promoting the helical propensity of the protein does not appear to be a suitable strategy to overcome the aggregation related problems of industrially important proteins such as papain, which are not only required to be protected against aggregation but also need to remain functionally active in the presence of aggregation inhibitors. PMID:25365488

Qadeer, A; Zaman, M; Khan, R H

2014-08-01

54

Mutations in the 50S ribosomal subunit of Brachyspira hyodysenteriae associated with altered minimum inhibitory concentrations of pleuromutilins.  

PubMed

Brachyspira hyodysenteriae, the causative agent of swine dysentery, is responsible for severe mucohaemorrhagic colitis with considerable financial loss to worldwide swine production. Antimicrobial resistance against macrolides and lincosamides is widespread and the mechanisms are well known. Currently, the most common treatment for swine dysentery is the use of pleuromutilins and resistance to these drugs also is increasingly being reported. Although resistance mechanisms against pleuromutilins are less clear than for other drugs, they seem to involve alterations of the peptidyl transferase centre (PTC), including ribosomal RNA and the ribosomal protein L3. The present study was conducted to examine molecular mechanisms of resistance on a representative set of B. hyodysenteriae field strains with different resistance patterns. In total, we identified 24 single nucleotide polymorphisms (SNPs) in the 23S rRNA gene and genes of the ribosomal proteins L3, L4, L2 and L22. The SNP in the ribosomal protein gene L3 at position 443 led to an amino acid substitution of asparagine (Asn) by serine (Ser) at position 148, significantly associated with MICs for pleuromutilins. Based on this SNP a correct assignment of 71% of the strains with respect to a threshold of >0.625 ?g tiamulin/ml was reached. Unexpectedly low MICs in some of the Asn-strains were explained by a second SNP at position 2535 of the 23S rRNA. Our results clearly show the associations between MICs for pleuromutilins and mutations in their binding site. A complete list of SNPs that influence MICs of B. hyodysenteriae strains is needed to enable the interpretation of future molecular susceptibility testing. PMID:24948419

Hillen, Sonja; Willems, Hermann; Herbst, Werner; Rohde, Judith; Reiner, Gerald

2014-08-01

55

GABAA receptor antagonism increases NMDA receptor inhibition by isoflurane at a minimum alveolar concentration  

PubMed Central

Objective At the minimum alveolar concentration (MAC), isoflurane potentiates GABAA receptor currents and inhibits NMDA receptor currents, and these actions may be important for producing anesthesia. However, isoflurane modulates GABAA receptors more potently than NMDA receptors. The objective of this study was to test whether isoflurane would function as a more potent NMDA receptor antagonist if its efficacy at GABAA receptors was decreased. Study design Prospective experimental study. Animals Fourteen 10-week-old male Sprague–Dawley rats weighing 269 ± 12 g. Methods Indwelling lumbar subarachnoid catheters were surgically placed in isoflurane-anesthetized rats. Two days later, the rats were anesthetized with isoflurane, and artificial CSF containing either 0 or 1 mg kg?1 picrotoxin, a GABAA receptor antagonist, was infused intrathecally at 1 ?L minute?1. The baseline isoflurane MAC was then determined using a standard tail clamp technique. MK801 (dizocilpine), an NMDA receptor antagonist, was then administered intravenously at 0.5 mg kg?1. Isoflurane MAC was re-measured. Results Picrotoxin increased isoflurane MAC by 16% compared to controls. MK801 significantly decreased isoflurane MAC by 0.72% of an atmosphere in controls versus 0.47% of an atmosphere in rats receiving intrathecal picrotoxin. Conclusions and clinical relevance A smaller MK801 MAC-sparing effect in the picrotoxin group is consistent with greater NMDA antagonism by isoflurane in these animals, since it suggests that fewer NMDA receptors are available upon which MK801 could act to decrease isoflurane MAC. Decreasing isoflurane GABAA potentiation increases isoflurane NMDA antagonism at MAC. Hence, the magnitude of an anesthetic effect on a given channel or receptor at MAC may depend upon effects at other receptors. PMID:21492389

Brosnan, Robert J

2011-01-01

56

Identification of the major ACE-inhibitory peptides produced by enzymatic hydrolysis of a protein concentrate from cuttlefish wastewater.  

PubMed

The aim of this work was the purification and identification of the major angiotensin converting enzyme (ACE) inhibitory peptides produced by enzymatic hydrolysis of a protein concentrate recovered from a cuttlefish industrial manufacturing effluent. This process consisted on the ultrafiltration of cuttlefish softening wastewater, with a 10 kDa cut-off membrane, followed by the hydrolysis with alcalase of the retained fraction. Alcalase produced ACE inhibitors reaching the highest activity (IC?? = 76.8 ± 15.2 ?g mL?ą) after 8 h of proteolysis. Sequential ultrafiltration of the 8 h hydrolysate with molecular weight cut-off (MWCO) membranes of 10 and 1 kDa resulted in the increased activity of each permeate, with a final IC?? value of 58.4 ± 4.6 ?g mL?ą. Permeate containing peptides lower than 1 kDa was separated by reversed-phase high performance liquid chromatography (RP-HPLC). Four fractions (A-D) with potent ACE inhibitory activity were isolated and their main peptides identified using high performance liquid chromatography coupled to an electrospray ion trap Fourier transform ion cyclotron resonance-mass spectrometer (HPLC-ESI-IT-FTICR) followed by comparison with databases and de novo sequencing. The amino acid sequences of the identified peptides contained at least one hydrophobic and/or a proline together with positively charged residues in at least one of the three C-terminal positions. The IC?? values of the fractions ranged from 1.92 to 8.83 ?g mL?ą, however this study fails to identify which of these peptides are ultimately responsible for the potent antihypertensive activity of these fractions. PMID:24619242

Amado, Isabel Rodríguez; Vázquez, José Antonio; González, Pilar; Esteban-Fernández, Diego; Carrera, Mónica; Pińeiro, Carmen

2014-03-01

57

Identification of the Major ACE-Inhibitory Peptides Produced by Enzymatic Hydrolysis of a Protein Concentrate from Cuttlefish Wastewater  

PubMed Central

The aim of this work was the purification and identification of the major angiotensin converting enzyme (ACE) inhibitory peptides produced by enzymatic hydrolysis of a protein concentrate recovered from a cuttlefish industrial manufacturing effluent. This process consisted on the ultrafiltration of cuttlefish softening wastewater, with a 10 kDa cut-off membrane, followed by the hydrolysis with alcalase of the retained fraction. Alcalase produced ACE inhibitors reaching the highest activity (IC50 = 76.8 ± 15.2 ?g mL?1) after 8 h of proteolysis. Sequential ultrafiltration of the 8 h hydrolysate with molecular weight cut-off (MWCO) membranes of 10 and 1 kDa resulted in the increased activity of each permeate, with a final IC50 value of 58.4 ± 4.6 ?g mL?1. Permeate containing peptides lower than 1 kDa was separated by reversed-phase high performance liquid chromatography (RP-HPLC). Four fractions (A–D) with potent ACE inhibitory activity were isolated and their main peptides identified using high performance liquid chromatography coupled to an electrospray ion trap Fourier transform ion cyclotron resonance-mass spectrometer (HPLC-ESI-IT-FTICR) followed by comparison with databases and de novo sequencing. The amino acid sequences of the identified peptides contained at least one hydrophobic and/or a proline together with positively charged residues in at least one of the three C-terminal positions. The IC50 values of the fractions ranged from 1.92 to 8.83 ?g mL?1, however this study fails to identify which of these peptides are ultimately responsible for the potent antihypertensive activity of these fractions. PMID:24619242

Rodríguez Amado, Isabel; Vázquez, José Antonio; González, Pilar; Esteban-Fernández, Diego; Carrera, Mónica; Pińeiro, Carmen

2014-01-01

58

Comparative production of channel catfish and channel x blue hybrid catfish subjected to two minimum dissolved oxygen concentrations  

Technology Transfer Automated Retrieval System (TEKTRAN)

The effect of daily minimum dissolved oxygen concentration on growth and yield (kg/ha) of the channel catfish (Ictalurus punctatus) and the channel x blue hybrid catfish (I. punctatus female x I. furcatus male), which shared the Jubilee strain of channel catfish as the maternal parent, was evaluated...

59

The relationship between age and minimum alveolar concentration of sevoflurane for maintaining bispectral index below 50 in children.  

PubMed

We evaluated the minimum alveolar concentration of sevoflurane required to maintain the bispectral index below 50 in children. We studied 55 children, divided into 1-year-old, 2- to 4-year-old and 5- to 9-year-old groups and used Dixon's up-and-down method and probit analysis. In the 1-year-old group, the bispectral index values remained above 50, with the end-tidal sevoflurane concentration reaching 4.0% or higher. The minimum alveolar concentration of sevoflurane for maintaining the bispectral index below 50 was significantly higher in the 2- to 4-year-old group (2.33%, 95% CI 2.25-2.57) than in the 5- to 9-year-old group (2.10%, 95% CI 1.94-2.25; p = 0.005). We conclude that assessing the depth of anaesthesia using bispectral index is unreliable in children aged < 2 years anaesthetised with sevoflurane. PMID:25271891

Tokuwaka, J; Satsumae, T; Mizutani, T; Yamada, K; Inomata, S; Tanaka, M

2015-03-01

60

Antibacterial activity against ?- lactamase producing Methicillin and Ampicillin-resistants Staphylococcus aureus: fractional Inhibitory Concentration Index (FICI) determination  

PubMed Central

Background The present study reports the antibacterial capacity of alkaloid compounds in combination with Methicillin and Ampicillin-resistants bacteria isolated from clinical samples. The resistance of different bacteria strains to the current antibacterial agents, their toxicity and the cost of the treatment have led to the development of natural products against the bacteria resistant infections when applied in combination with conventional antimicrobial drugs. Method The antibacterial assays in this study were performed by using inhibition zone diameters, MIC, MBC methods, the time-kill assay and the Fractional Inhibitory Concentration Index (FICI) determination. On the whole, fifteen Gram-positive bacterial strains (MRSA/ARSA) were used. Negative control was prepared using discs impregnated with 10 % DMSO in water and commercially available Methicillin and Ampicillin from Alkom Laboratories LTD were used as positive reference standards for all bacterial strains. Results We noticed that the highest activities were founded with the combination of alkaloid compounds and conventional antibiotics against all bacteria strains. Then, results showed that after 7 h exposition there was no viable microorganism in the initial inoculums. Conclusion The results of this study showed that alkaloid compounds in combination with conventional antibiotics (Methicillin, Ampicillin) exhibited antimicrobial effects against microorganisms tested. These results validate the ethno-botanical use of Cienfuegosia digitata Cav. (Malvaceae) in Burkina Faso. Moreover, this study demonstrates the potential of this herbaceous as a source of antibacterial agent that could be effectively used for future health care purposes. PMID:22716026

2012-01-01

61

Anti-biofilm activity of sub-inhibitory povidone-iodine concentrations against Staphylococcus epidermidis and Staphylococcus aureus.  

PubMed

Biomaterial-related infections continue to hamper the success of reconstructive and arthroplasty procedures in orthopaedic surgery. Staphylococci are the most common etiologic agents, with biofilm formation representing a major virulence factor. Biofilms increase bacterial resistance to antimicrobial agents and host immune responses. In staphylococci, production of polysaccharide intercellular adhesin (PIA) by the enzyme products of the icaADBC operon is the best understood mechanism of biofilm development, making the ica genes a potential target for biofilm inhibitors. In this study we report that the antibacterial agent povidone-iodine (PI) also has anti-biofilm activity against Staphylococcus epidermidis and Staphylococcus aureus at sub-inhibitory concentrations (p < 0.001). Inhibition of biofilm by PI correlated with decreased transcription of the icaADBC operon, which in turn correlated with activation of the icaR transcriptional repressor in Staphylococcus epidermidis. These data reveal an additional therapeutic benefit of PI and suggest that studies to evaluate suitability of PI as biomaterial coating agent to reduce device-related infections are merited. PMID:20187117

Oduwole, Kayode O; Glynn, Aaron A; Molony, Diarmuid C; Murray, David; Rowe, Sarah; Holland, Linda M; McCormack, Damian J; O'Gara, James P

2010-09-01

62

Plasma Concentration Profiles of Simvastatin 3Hydroxy3-Methylglutaryl-Coenzyme A Reductase Inhibitory Activity in Kidney Transplant Recipients with and without Ciclosporin  

Microsoft Academic Search

A few cases of severe rhabdomyolysis have been reported in heart transplant recipients treated simultaneously with ciclosporin (CS) and the 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor lovastatin. When measured, plasma lovastatin HMG-CoA reductase inhibitor concentrations in these patients were higher than expected. This prompted us to study the plasma concentration profiles of simvastatin HMG-CoA reductase inhibitory activity after a single dose

Margret Arnadottir; Lars-Olof Eriksson; Hans Thysell; John D. Karkas

1993-01-01

63

CO-OCCURRENCE PATTERNS OF GASEOUS AIR POLLUTANT PAIRS AT DIFFERENT MINIMUM CONCENTRATIONS IN THE UNITED STATES (JOURNAL VERSION)  

EPA Science Inventory

The frequency of co-occurrences for SO2/NO2, SO2/O3 and O3/NO2 at rural and remote monitoring sites in the United States was characterized for the months of May-September for the years 1978-1982. Minimum hourly concentrations of 0.03 and 0.05 ppm of each gas were used as the crit...

64

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

PubMed Central

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. PMID:22605968

Moen, Birgitte; Rudi, Knut; Bore, Erlend; Langsrud, Solveig

2012-01-01

65

Decrease in Shiga toxin expression using a minimal inhibitory concentration of rifampicin followed by bactericidal gentamicin treatment enhances survival of Escherichia coli O157:H7-infected BALB/c mice  

PubMed Central

Background Treatment of Escherichia coli O157:H7 infections with antimicrobial agents is controversial due to an association with potentially fatal sequelae. The production of Shiga toxins is believed to be central to the pathogenesis of this organism. Therefore, decreasing the expression of these toxins prior to bacterial eradication may provide a safer course of therapy. Methods The utility of decreasing Shiga toxin gene expression in E. coli O157:H7 with rifampicin prior to bacterial eradication with gentamicin was evaluated in vitro using real-time reverse-transcription polymerase chain reaction. Toxin release from treated bacterial cells was assayed for with reverse passive latex agglutination. The effect of this treatment on the survival of E. coli O157:H7-infected BALB/c mice was also monitored. Results Transcription of Shiga toxin-encoding genes was considerably decreased as an effect of treating E. coli O157:H7 in vitro with the minimum inhibitory concentration (MIC) of rifampicin followed by the minimum bactericidal concentration (MBC) of gentamicin (> 99% decrease) compared to treatment with gentamicin alone (50-75% decrease). The release of Shiga toxins from E. coli O157:H7 incubated with the MIC of rifampicin followed by addition of the MBC of gentamicin was decreased as well. On the other hand, the highest survival rate in BALB/c mice infected with E. coli O157:H7 was observed in those treated with the in vivo MIC equivalent dose of rifampicin followed by the in vivo MBC equivalent dose of gentamicin compared to mice treated with gentamicin or rifampicin alone. Conclusions The use of non-lethal expression-inhibitory doses of antimicrobial agents prior to bactericidal ones in treating E. coli O157:H7 infection is effective and may be potentially useful in human infections with this agent in addition to other Shiga toxin producing E. coli strains. PMID:21906403

2011-01-01

66

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  

PubMed Central

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. PMID:24174916

Sandri, Andrea; Samaila, Elena; Magnan, Bruno

2013-01-01

67

Evaluation of AQUI-S(TM) (efficacy and minimum toxic concentration) as a fish anaesthetic/sedative for public aquaculture in the United States  

USGS Publications Warehouse

A preliminary evaluation of efficacy and minimum toxic concentration of AQUI-S(TM), a fish anaesthetic/sedative, was determined in two size classes of six species of fish important to US public aquaculture (bluegill, channel catfish, lake trout, rainbow trout, walleye and yellow perch). In addition, efficacy and minimum toxic concentration were determined in juvenile-young adult (fish aged 1 year or older) rainbow trout acclimated to water at 7 ??C, 12 ??C and 17 ??C. Testing concentrations were based on determinations made with range-finding studies for both efficacy and minimum toxic concentration. Most of the tested juvenile-young adult fish species were induced in 3 min or less at a nominal AQUI-S(TM) concentration of 20 mg L-1. In juvenile-young adult fish, the minimum toxic concentration was at least 2.5 times the selected efficacious concentration. Three out of five species of fry-fingerlings (1.25-12.5 cm in length and < 1 year old) were induced in ??? 4.1 min at a nominal concentration of 20 mg L-1 AQUI-S(TM), with the other two species requiring nominal concentrations of 25 and 35 mg L-1 for similar times of induction. Recovery times were ??? 7.3 rain for all species in the two size classes. In fry-fingerlings, the minimum toxic concentration was at least 1.4 times the selected efficacious concentration. There appeared to be little relationship between size of fish and concentrations or times to induction, recovery times and minimum toxic concentration. The times required for induction and for recovery were increased in rainbow trout as the acclimation temperature was reduced.

Stehly, G.R.; Gingerich, W.H.

1999-01-01

68

Serum concentrations and ex vivo inhibitory/bactericidal activity of clindamycin after administration of two oral dosages.  

PubMed

Two dosages of clindamycin, 300 and 600 mg, were given orally to 10 patients each. The patients were admitted for minor elective surgery. Their mean age was 39.3 years; mean weight was 67.5 kg. None of them had taken antibiotics for at least 1 month. After administration of a single dose, blood samples were obtained at 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10 and 12 h after dosing. Drug levels were determined by the bioassay method using Micrococcus luteus as test organism. Serum inhibitory and bactericidal activities against five isolates each of Staphylococcus aureus and Streptococcus pyogenes were determined by the microdilution method according to the National Committee for Clinical Laboratory Standards guidelines. The mean peak serum level was 3.4 mg/l for the 300-mg dose and 4.8 mg/l for the 600-mg dose. The mean reciprocal peak inhibitory titers for the 300-/600-mg doses were 13.7/23.8 and 15.2/34.7 against S. aureus and S. pyogenes, respectively. Most serum samples did not show bactericidal activity against S. aureus. PMID:9209778

Dan, M; Yampolsky, E; Poch, F

1997-01-01

69

In Vitro Inhibitory Effects of Hinokitiol on Proliferation of Chlamydia trachomatis  

PubMed Central

The inhibitory effects of hinokitiol (?-thujaplicin) on Chlamydia trachomatis D/UW-3/Cx were shown by MIC, minimum lethal concentration (MLC), and preinoculation minimal microbicidal concentration assays using HeLa 229 cells. The MIC and the MLC were both 32 ?g/ml. Further evaluation of hinokitiol as a topical agent against C. trachomatis is warranted. PMID:15917561

Yamano, Hiroaki; Yamazaki, Tsutomu; Sato, Kozue; Shiga, Sadashi; Hagiwara, Toshikatsu; Ouchi, Kazunobu; Kishimoto, Toshio

2005-01-01

70

Sub-Inhibitory Concentrations of Human ?-defensin Potentiate Neutralizing Antibodies against HIV-1 gp41 Pre-Hairpin Intermediates in the Presence of Serum  

PubMed Central

Human defensins are at the forefront of the host responses to HIV and other pathogens in mucosal tissues. However, their ability to inactivate HIV in the bloodstream has been questioned due to the antagonistic effect of serum. In this study, we have examined the effect of sub-inhibitory concentrations of human ?-defensin HNP-1 on the kinetics of early steps of fusion between HIV-1 and target cells in the presence of serum. Direct measurements of HIV-cell fusion using an enzymatic assay revealed that, in spite of the modest effect on the extent of fusion, HNP-1 prolonged the exposure of functionally important transitional epitopes of HIV-1 gp41 on the cell surface. The increased lifetime of gp41 intermediates in the presence of defensin was caused by a delay in the post-coreceptor binding steps of HIV-1 entry that correlated with the marked enhancement of the virus' sensitivity to neutralizing anti-gp41 antibodies. By contrast, the activity of antibodies to gp120 was not affected. HNP-1 appeared to specifically potentiate antibodies and peptides targeting the first heptad repeat domain of gp41, while its effect on inhibitors and antibodies to other gp41 domains was less prominent. Sub-inhibitory concentrations of HNP-1 also promoted inhibition of HIV-1 entry into peripheral blood mononuclear cells by antibodies and, more importantly, by HIV-1 immune serum. Our findings demonstrate that: (i) sub-inhibitory doses of HNP-1 potently enhance the activity of a number of anti-gp41 antibodies and peptide inhibitors, apparently by prolonging the lifetime of gp41 intermediates; and (ii) the efficiency of HIV-1 fusion inhibitors and neutralizing antibodies is kinetically restricted. This study thus reveals an important role of ?-defensin in enhancing adaptive immune responses to HIV-1 infection and suggests future strategies to augment these responses. PMID:23785290

Demirkhanyan, Lusine; Marin, Mariana; Lu, Wuyuan; Melikyan, Gregory B.

2013-01-01

71

A growth inhibitory model with SO(x) influenced effective growth rate for estimation of algal biomass concentration under flue gas atmosphere.  

PubMed

A theoretical model for the prediction of biomass concentration under rice husk flue gas emission has been developed. The growth inhibitory model (GIM) considers the CO2 mass transfer rate, the critical SOx concentration and its role in pH-based inter-conversion of bicarbonate. The calibration and subsequent validation of the growth profile of Nannochloropsis limnetica at 2% and 10% (v/v) CO2 showed that the predicted values were consistent with the measured values, with r(2) being 0.96 and 0.98, respectively, and p<0.001 in both cases. The constants used in the GIM for the prediction of biomass have been justified using sensitivity analysis. GIM applicability was defined as ±30% of the calibrated flow rate (3.0 L min(-1)). This growth model can be applied to predict algal growth in photo-bioreactors treated with flue gas in the generation of biomass feed stock for biofuel production. PMID:24300846

Ronda, Srinivasa Reddy; Kethineni, Chandrika; Parupudi, Lakshmi Chandrika Pavani; Thunuguntla, Venkata Bala Sai Chaitanya; Vemula, Sandeep; Settaluri, Vijaya Saradhi; Allu, Prasada Rao; Grande, Suresh Kumar; Sharma, Suraj; Kandala, Chari Venkatakrishna

2014-01-01

72

Mechanism of inhibition of P-glycoprotein mediated efflux by Pluronic P123/F127 block copolymers: relationship between copolymer concentration and inhibitory activity.  

PubMed

The aim of this study was to clarify the relationship between the concentration of Pluronic P123/F127 block copolymers and P-glycoprotein (P-gp) inhibitory potency. Modulation of multidrug resistance (MDR) by Pluronic P123/F127 was evaluated in P-gp over-expressing human breast cancer cell line MCF-7/ADR and its non-P-gp over-expressing counterpart MCF-7 cells. Four different probes (known as P-gp substrates) including rhodamine 123 (R-123), rhodamine 6G (R-6G), doxorubicin (DOX), and paclitaxel (PTX) were applied to investigate the impact of Pluronic P123/F127 copolymers with different concentrations on the intracellular accumulation of these probes. Additionally, the intracellular ATP and mitochondrial transmembrane potential in MCF-7/ADR cells were determined over a wide concentration range of Pluronic P123/F127. Furthermore, the endocytic mechanisms of Pluronic micelles were performed. It was suggested that P-gp substrate hydrophobicity and the concentration of P123/F127 copolymers had little impact on P-gp inhibitory activity of Pluronic P123/F127 itself. Intracellular ATP depletion was the main mechanism of Pluronic P123/F127 for P-gp inhibition. In vitro cytotoxicity study was also conducted in order to compare cytotoxic effect among different PTX formulations. It indicated that the IC50 of PTX-loaded Pluronic P123/F127 mixed micelles was 6.3-fold lower than free PTX and 2.3-fold lower than Taxol, respectively. Therefore, Pluronic P123/F127 polymeric micelles could be considered a promising drug delivery system to overcome MDR in cancer therapy. PMID:23089310

Wei, Zhang; Yuan, Shi; Hao, Junguo; Fang, Xiaoling

2013-02-01

73

A growth inhibitory model with SOx influenced effective growth rate for estimation of algal biomass concentration under flue gas atmosphere  

Technology Transfer Automated Retrieval System (TEKTRAN)

A theoretical model for the prediction of biomass concentration under real flue gas emission has been developed. The model considers the CO2 mass transfer rate, the critical SOx concentration and its role on pH based inter-conversion of bicarbonate in model building. The calibration and subsequent v...

74

The effect of inversion times on the minimum signal intensity of the contrast agent concentration using inversion recovery t1-weighted fast imaging sequence  

PubMed Central

Background: Inversion recovery (IR) pulse sequences can generate T1-weighted images with a different range of inversion time (TI) to suppress or null the signal intensity (SI) for a specified tissue. In this study, we aimed to investigate the effect of TI values on the concentration of the contrast agent, which leads to a minimum signal intensity, using an inversion recovery T1-weighted 3-dimensional fast-gradient echo imaging sequence. Methods: A phantom was designed to hold 25 vials which contained different (between 0 and 19.77mmol/L of (Gd-DTPA)) concentrations of the contrast agent. We used the vials of different concentrations to measure SI using IR sequences with different inversion times (TI, 100-3000ms). Results: The results of this study revealed that the T1 recovery curve did not cross the x- axis for the lower TI. Therefore, a minimum SI can be observed from the concentration of the contrast agent versus SI curves. The findings of this study also revealed that the concentration of the contrast agent, which leads to a minimum SI, is dependent on the TI and the minimum SI will be increased at higher TI concentrations. Conclusion: In conclusion, when the TI parameter is used to suppress the SI of the specified tissues in clinical studies (e.g., fat suppression or blood suppression in perfusion measurements), it should be chosen with great caution.

Nazarpoor, Mahmood

2014-01-01

75

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  

PubMed Central

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 17.5% w/v solids, the final strain (AJP50) produced ethanol at more than 80% of the maximum theoretical yield after 72 hours of fermentation, and reached more than 90% of the maximum theoretical yield after 120 hours of fermentation. Conclusions Our results show that fermentation of pretreated pine containing liquid and solids, including any inhibitory compounds generated during pretreatment, is possible at higher solids loadings than those previously reported in the literature. Using our evolved strain, efficient fermentation with reduced inoculum sizes and shortened process times was possible, thereby improving the overall economic viability of a woody biomass-to-ethanol conversion process. PMID:22074982

2011-01-01

76

Optimization of Crystals of an Inhibitory Antibody of Urokinase Plasminogen Activator Receptor (uPAR) with Hydrogen Peroxide and Low Protein Concentration  

SciTech Connect

Optimization of protein crystal formation is often a necessary step leading to diffraction-quality crystals to enable collection of a full X-ray data set. Typical protein crystal optimization involves screening different components, e.g., pH, precipitants, and additives of the precipitant solution. Here we present an example using an inhibitory antibody of urokinase plasminogen activator receptor (uPAR) where such procedures did not yield diffracting crystals. In contrast, it was the treatment of the protein with hydrogen peroxide incubation and the protein concentration reduction that were found to be key factors in obtaining diffracting crystals. Final crystals diffracted to 1.75 {angstrom}, and belong to orthorhombic P212121 space group with unit cell parameters a = 37.162 {angstrom}, b = 84.474 {angstrom}, c = 134.030 {angstrom}, and contain one molecule of Fab fragment of anti-uro kinase receptor antibody in the asymmetric unit.

Li, Yongdong; Shi, Xiaoli; Parry, Graham; Chen, Liqing; Callahan, Jennifer A.; Mazar, Andrew P.; Huang, Mingdong (UAH); (Attenuon LLC); (Chinese Aca. Sci.)

2010-07-19

77

The minimal inhibitory concentration for sulbactam was not associated with the outcome of infections caused by carbapenem-resistant Acinetobacter sp. treated with ampicillin/sulbactam  

PubMed Central

OBJECTIVE: The objective of this study was to evaluate whether the outcomes of carbapenem-resistant Acinetobacter infections treated with ampicillin/sulbactam were associated with the in vitro susceptibility profiles. METHODS: Twenty-two infections were treated with ampicillin/sulbactam. The median treatment duration was 14 days (range: 3-19 days), and the median daily dose was 9 g (range: 1.5-12 g). The median time between Acinetobacter isolation and treatment was 4 days (range: 0-11 days). RESULTS: The sulbactam minimal inhibitory concentration (MIC) ranged from 2.0 to 32.0 mg/L, and the MIC was not associated with patient outcome, as 4 of 5 (80%) patients with a resistant infection (MIC?16), 5 of 10 (50%) patients with intermediate isolates (MIC of 8) and only 1 of 7 (14%) patients with susceptible isolates (MIC ?4) survived hospitalization. CONCLUSION: These findings highlight the need to improve the correlation between in vitro susceptibility tests and clinical outcome. PMID:23778333

de Oliveira, Maura S.; Costa, Silvia Figueiredo; de Pedri, Ewerton; van der Heijden, Inneke; Levin, Anna Sara S.

2013-01-01

78

Ticarcillin/clavulanic acid: determination of minimal inhibitory concentrations against bacterial strains isolated from patients in intensive care units. Comparison with other agents.  

PubMed

A total of 303 bacterial strains isolated from bronchoaspirates of Intensive Care Unit (ICU) patients, collected through June and December 1993, were tested for susceptibility to ticarcillin/clavulanic acid, imipenem, amikacin, ceftazidime, ciprofloxacin and piperacillin. The minimal inhibitory concentration (MIC) for each antibiotic was determined according to the NCCLS, by means of serial dilution on microplates. The isolates, 80.8% of which were beta-lactamase producing strains, belonged to Pseudomonas aeruginosa (79 strains), Pseudomonas fluorescens (8 strains), Xanthomonas maltophila (25 strains), Escherichia coli (16 strains), Klebsiella-Enterobacter-Serratia (KES) (62 strains), Proteus spp. (15 strains), Acinetobacter spp. (22 strains), Moraxella spp. (15 strains), Bacteroides catarrhalis (8 strains), Haemophilus spp. (11 strains), Staphylococcus aureus (32 strains), Enterococcus faecalis (10 strains). The highest rate of susceptibility to ticarcillin/clavulanic acid (100%) was detected among E. faecalis (MIC 2-16 micrograms/ml), B. catarrhalis (MIC 1-4 micrograms/ml) and Haemophilus spp. (MIC 1-4 micrograms/ml). Among the non-fermenting microorganisms ticarcillin/-clavulanic acid showed good activity toward P. aeruginosa and P. fluorescens (86% and 75% respectively). It was also very active against X. maltophilia with a susceptibility of 96%. Susceptibility to the other antibiotics tested was within the range of 16% and 28%. PMID:8708742

Pasargiklian, I; Lusco, G; Paizis, G; Mascheroni, E

1996-04-01

79

Nearest Neighbor Averaging and its Effect on the Critical Level and Minimum Detectable Concentration for Scanning Radiological Survey Instruments that Perform Facility Release Surveys.  

SciTech Connect

Through the SNL New Mexico Small Business Assistance (NMSBA) program, several Sandia engineers worked with the Environmental Restoration Group (ERG) Inc. to verify and validate a novel algorithm used to determine the scanning Critical Level (L c ) and Minimum Detectable Concentration (MDC) (or Minimum Detectable Areal Activity) for the 102F scanning system. Through the use of Monte Carlo statistical simulations the algorithm mathematically demonstrates accuracy in determining the L c and MDC when a nearest-neighbor averaging (NNA) technique was used. To empirically validate this approach, SNL prepared several spiked sources and ran a test with the ERG 102F instrument on a bare concrete floor known to have no radiological contamination other than background naturally occurring radioactive material (NORM). The tests conclude that the NNA technique increases the sensitivity (decreases the L c and MDC) for high-density data maps that are obtained by scanning radiological survey instruments.

Fournier, Sean Donovan; Beall, Patrick S [Sandia National Laboratories, Livermore, CA; Miller, Mark L.

2014-08-01

80

Inhibitory neuropeptides and intrinsic inhibitory innervation of descending human colon  

Microsoft Academic Search

The effects of aging on inhibitory neuropeptide concentrations and intrinsic inhibitory innervation of circular muscle were investigated using normal descending colon obtained at surgery. Immunoreactive vasoactive intestinal peptide, peptide histidine-methionine, met5-enkephalin, neuropeptide Y, and somatostatin were extracted from specimens of muscularis externa (patient ages: 19–84 years) and measured by radioimmunoassay. Intracellular electrical activity was recorded from strips of circular muscle

Timothy R. Koch; J. Aidan Carney; V. L. W. Go; Joseph H. Szurszewski

1991-01-01

81

Prior determination of baseline minimum alveolar concentration (MAC) of isoflurane does not influence the effect of ketamine on MAC in rabbits.  

PubMed

The objective of this study was to compare the effect on the minimum alveolar concentration (MAC) of isoflurane when ketamine was administered either after or without prior determination of the baseline MAC of isoflurane in rabbits. Using a prospective randomized crossover study, 8 adult, female New Zealand rabbits were allocated to 2 treatment groups. Anesthesia was induced and maintained with isoflurane. Group 1 (same-day determination) had the MAC-sparing effect of ketamine [1 mg/kg bodyweight (BW) bolus followed by a constant rate infusion (CRI) of 40 ?g/kg BW per min, given by intravenous (IV)], which was determined after the baseline MAC of isoflurane was determined beforehand. A third MAC determination was started 30 min after stopping the CRI. Group 2 (separate-day determination) had the MAC-sparing effect of ketamine determined without previous determination of the baseline MAC of isoflurane. A second MAC determination was started 30 min after stopping the CRI. In group 1, the MAC of isoflurane (2.15 ± 0.09%) was significantly decreased by ketamine (1.63 ± 0.07%). After stopping the CRI, the MAC was significantly less (2.04 ± 0.11%) than the baseline MAC of isoflurane and significantly greater than the MAC during the CRI. In group 2, ketamine decreased isoflurane MAC (1.53 ± 0.22%) and the MAC increased significantly (1.94 ± 0.25%) after stopping the CRI. Minimum alveolar concentration (MAC) values did not differ significantly between the groups either during ketamine administration or after stopping ketamine. Under the study conditions, prior determination of the baseline isoflurane MAC did not alter the effect of ketamine on MAC. Both methods of determining MAC seemed to be valid for research purposes. PMID:23543951

Gianotti, Giacomo; Valverde, Alexander; Sinclair, Melissa; Dyson, Doris H; Gibson, Thomas; Johnson, Ron

2012-10-01

82

Anesthesia with Isoflurane and Sevoflurane in the Crested Serpent Eagle (Spilornis cheela hoya): Minimum Anesthetic Concentration, Physiological Effects, Hematocrit, Plasma Chemistry and Behavioral Effects  

PubMed Central

ABSTRACT The initial goal of this study was to determine the minimum anesthetic concentration (MAC) for isoflurane (ISO) and sevoflurane (SEVO) for the crested serpent eagle. Next, we compared the anesthetic effects of each on the physiological effects, hematocrit, plasma chemistry values and behavior in spontaneously breathing captive adult crested serpent eagles. Sixteen eagles were randomly allocated to two groups for anesthesia with ISO (n=8) or SEVO (n=8). First, we measured the MAC values of ISO and SEVO, and four weeks later, we investigated the effect of each on the physiological effects, hematocrit (HCT) and plasma chemistry values. The MAC values of ISO and SEVO for crested serpent eagles were 1.46 ± 0.30 and 2.03 ± 0.32%, respectively. The results revealed no significant differences between the two anesthetics in induction time, while time of extubation to recovery was significantly shorter with SEVO. A time-related increase in end-tidal CO2 and decreases in body temperature and respiratory rates were observed during anesthesia with each anesthetic. There were no significant differences between the effect of the two anesthetics on heart rate, hematocrit, plasma chemistry values or respiration, although each caused minor respiration depression. We concluded that SEVO is a more effective inhalant agent than ISO for use in eagles, showing the most rapidest induction and recovery from anesthesia. PMID:23955396

CHAN, Fang-Tse; CHANG, Geng-Ruei; WANG, Hsien-Chi; HSU, Tien-Huan

2013-01-01

83

Isoflurane Depression of Spinal Nociceptive Processing and Minimum Alveolar Anesthetc Concentration are not Attenuated in Mice Expressing Isoflurane Resistant ?–Aminobutyric Acid-Type A Receptors  

PubMed Central

Anesthetics produce immobility and depress spinal nociceptive processing, but the exact sites and mechanisms of anesthetic action are unknown. The gamma-aminobutyric acid type-A (GABAA) receptor is thought to be important to anesthetic action. We studied knockin mice that had mutations in the alpha1 subunit of the GABAA receptor that imparts resistance to isoflurane in in vitro systems. We determined the isoflurane minimum alveolar concentration (MAC) that produces immobility in 50% of subjects and responses of lumbar neurons (single-unit recordings) to noxious stimulation (5 s pinch) of the hindpaw. Isoflurane MAC did not differ between wild-type (1.1 ± 0.1%) and knock-in (1.1 ± 0.1%) mice. Isoflurane depressed neuronal responses to noxious stimulation (60 sec period during and after pinch) similarly in both wild-type and knock-in mice (555 ± 133 and 636 ±106 impulses/min, respectively, at 0.8 MAC and 374 ± 81 and 409 ±85 impulses/min at 1.2 MAC). We conclude that isoflurane enhancement of alpha1 -containing GABAA receptors is not required to produce immobility or depress spinal nociceptive processing. PMID:17543455

Kim, JongBun; Atherley, Richard; Werner, David F.; Homanics, Gregg E.; Carstens, Earl; Antognini, Joseph F.

2009-01-01

84

Isoflurane depression of spinal nociceptive processing and minimum alveolar anesthetic concentration are not attenuated in mice expressing isoflurane resistant gamma-aminobutyric acid type-A receptors.  

PubMed

Anesthetics produce immobility and depress spinal nociceptive processing, but the exact sites and mechanisms of anesthetic action are unknown. The gamma-aminobutyric acid type-A (GABAA) receptor is thought to be important to anesthetic action. We studied knock-in mice that had mutations in the alpha1 subunit of the GABAA receptor that imparts resistance to isoflurane in in vitro systems. We determined the isoflurane minimum alveolar concentration (MAC) that produces immobility in 50% of subjects and responses of lumbar neurons (single-unit recordings) to noxious stimulation (5 s pinch) of the hindpaw. Isoflurane MAC did not differ between wild-type (1.1+/-0.1%) and knock-in (1.1+/-0.1%) mice. Isoflurane depressed neuronal responses to noxious stimulation (60 s period during and after pinch) similarly in both wild-type and knock-in mice (555+/-133 and 636+/-106 impulses/min, respectively, at 0.8 MAC and 374+/-81 and 409+/-85 impulses/min at 1.2 MAC). We conclude that isoflurane enhancement of alpha1-containing GABAA receptors is not required to produce immobility or depress spinal nociceptive processing. PMID:17543455

Kim, JongBun; Atherley, Richard; Werner, David F; Homanics, Gregg E; Carstens, Earl; Antognini, Joseph F

2007-06-15

85

Concentration  

NSDL National Science Digital Library

This is the NCTM Android app of their familiar on line Illuminations game, "Concentration" ( cataloged separately ) which challenges a user to match whole numbers, shapes, fractions, or multiplication facts to equivalent representations. This game can be played by one or two players taking turns and can be played in clear pane mode, or for added challenge, with the windows closed.

2011-08-11

86

Effects of sub-lethal neurite outgrowth inhibitory concentrations of chlorpyrifos oxon on cytoskeletal proteins and acetylcholinesterase in differentiating N2a cells  

SciTech Connect

Previous work in our laboratory has shown that sub-lethal concentrations (1-10 {mu}M) of chlorpyrifos (CPF), diazinon (DZ) and diazinon oxon (DZO) inhibit the outgrowth of axon-like neurites in differentiating mouse N2a neuroblastoma cells concomitant with altered levels and/or phosphorylation state of axonal cytoskeleton and growth-associated proteins. The aim of the present work was to determine whether chlorpyrifos oxon (CPO) was capable of inhibiting N2a cell differentiation in a similar manner. Using experimental conditions similar to our previous work, sub-lethal concentrations (1-10 {mu}M) of CPO were found to inhibit N2a cell differentiation. However, unlike previous studies with DZ and DZO, there was a high level of sustained inhibition of acetylcholinesterase (AChE) in CPO treated cells. Impairment of neurite outgrowth was also associated with reduced levels of growth associated protein-43 and neurofilament heavy chain (NFH), and the distribution of NFH in cells stained by indirect immunofluorescence was disrupted. However, in contrast to previous findings for DZO, the absolute level of phosphorylated NFH was unaffected by CPO exposure. Taken together, the findings suggest that sub-lethal concentrations of CPO inhibit axon outgrowth in differentiating N2a cells and that this effect involves reduced levels of two proteins that play key roles in axon outgrowth and maintenance. Although the inhibition of neurite outgrowth is unlikely to involve AChE inhibition directly, further work will help to determine whether the persistent inhibition of AChE by CPO can account for the different effects induced by CPO and DZO on the levels of total and phosphorylated NFH. -- Highlights: Black-Right-Pointing-Pointer Sub-lethal levels of chlorpyrifos oxon inhibit neurite outgrowth in N2a cells Black-Right-Pointing-Pointer Acetylcholinesterase exhibits sustained inhibition throughout exposure Black-Right-Pointing-Pointer The levels of neurofilament heavy chain and GAP-43 protein are reduced Black-Right-Pointing-Pointer Neurofilament heavy chain forms aggregates in cell bodies Black-Right-Pointing-Pointer Thus at least two axon-associated cytoskeletal proteins are disrupted by this agent.

Flaskos, J., E-mail: flaskos@vet.auth.gr [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Nikolaidis, E. [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)] [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Harris, W. [School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom)] [School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom); Sachana, M. [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)] [Laboratory of Biochemistry and Toxicology, School of Veterinary Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Hargreaves, A.J., E-mail: alan.hargreaves@ntu.ac.uk [School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS (United Kingdom)

2011-11-15

87

Minimum Thermometers  

Microsoft Academic Search

SOME time ago a correspondence appeared in NATURE (vol. vi. pp. 122, 142, 221) on the subject of moisture deposited in minimum thermometers exposed on the grass. As I was at the time much annoyed with this myself I took up every hint I could get in the matter, though I must confess with indifferent success. I tried for a

Thomas Fawcett

1876-01-01

88

Spectroscopic characterization of extracellular polymeric substances from Escherichia coli and Serratia marcescens: suppression using sub-inhibitory concentrations of bismuth thiols.  

PubMed

Free and bound (or capsular) EPS produced by suspended cultures of Escherichia coli and Serratia marcescens were characterized in detail using colorimetric analysis of total proteins and polysaccharides, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and Auger electron spectroscopy (AES) in the presence and absence of bismuth-based antifouling agents. Subtle differences in the chemical composition of free and bound EPS were observed for both bacteria in the absence of bismuth. Total polysaccharides and proteins in free and bound EPS decreased upon treatment with subinhibitory concentrations of lipophilic bismuth thiols (bismuth dimercaptopropanol, BisBAL; bismuth ethanedithiol, BisEDT; and bismuth pyrithione, BisPYR), with 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 produced. Second derivative analysis of the amide I region of FTIR spectra revealed decreases in protein secondary structures in the presence of bismuth thiols. Hence, antifouling properties of bismuth thiols appear to originate in their ability to suppress O-acetylation and protein secondary structure formation in addition to free and bound EPS secretion. PMID:18937399

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

2008-11-01

89

Cholinergic Switching Within Neocortical Inhibitory  

E-print Network

. Cholinergic activation of subsets of cortical interneurons containing the inhibitory neurotransmitter -aminobuCholinergic Switching Within Neocortical Inhibitory Networks Zixiu Xiang, John R. Huguenard, David within cortical circuits. The functional relations between inhibitory and excitatory networks

Huguenard, John R.

90

Record Sea Ice Minimum  

NASA Technical Reports Server (NTRS)

Arctic sea ice reached a record low in September 2007, below the previous record set in 2005 and substantially below the long-term average. This image shows the Arctic as observed by the Advanced Microwave Scanning Radiometer for EOS (AMSR-E) aboard NASA's Aqua satellite on September 16, 2007. In this image, blue indicates open water, white indicates high sea ice concentration, and turquoise indicates loosely packed sea ice. The black circle at the North Pole results from an absence of data as the satellite does not make observations that far north. Three contour lines appear on this image. The red line is the 2007 minimum, as of September 15, about the same time the record low was reached, and it almost exactly fits the sea ice observed by AMSR-E. The green line indicates the 2005 minimum, the previous record low. The yellow line indicates the median minimum from 1979 to 2000.

2007-01-01

91

Nootropic dipeptide noopept enhances inhibitory synaptic transmission in the hippocampus.  

PubMed

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. PMID:25573367

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

2015-01-01

92

The inhibitory effect of Zingiber corallinum Hance essential oil on drug-resistant bacteria and evaluation of its acute toxicity  

PubMed Central

Summary Background The excessive and irregular use of antibiotics could result in the generation and diffusion of drug-resistant bacteria. The aim of this study was to investigate the inhibitory effect of Zingiber corallinum Hance essential oil (ZCHO) on drug-resistant bacteria, especially on drug-resistant Acinetobacter baumannii. Material/Methods Susceptibility testing was used to evaluate the effect of ZCHO on growth inhibition of drug-resistant bacteria by paper disk method. Mice orally administered with ZCHO were used to observe acute toxicity and to determine median lethal dose (LD50) of ZCHO. Broth dilution method was used to determine minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of ZCHO on drug-resistant Acinetobacter baumannii. Results ZCHO exhibited an obvious inhibitory effect not only on gram-negative drug-resistant bacteria including Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae and Acinetobacter baumannii, but also on gram-positive drug-resistant bacteria including Staphylococcus aureus, Staphylococcus epidermidis and Staphylococcus haemolyticus. The ZCHO containing 79% terpinen-4-ol revealed better bacteriostatic effect than ZCHO with 34% terpinen-4-ol. The LD50 of ZCHO was 1790.427 mg/kg. The MIC and MBC of ZCHO on drug-resistant Acinetobacter baumannii were 1457.81 mg/L. Conclusions ZCHO has obvious bacteriostasis and bactericidal effects, especially against drug-resistant Acinetobacter baumannii. Therefore, ZCHO is a promising natural bioactive component with antibacterial effect and satisfactory safety due to its low toxicity. PMID:21525802

Yang, Ce; Zhou, Lin-Lin; Wang, Hai-Yan; Huang, Su-Na; Liu, Qing; Hu, Shi-Lin; Li, Ting-Rong; Chen, Yan-Bing; Jiang, Jian-Xin

2011-01-01

93

The effect of various thidiazuron concentrations and 2,4-d exposure on somaclonal variation and shoot morphogenesis in birch  

E-print Network

, and eventually growth was arrested despite regular transfers. Leguay and Guern (1977), using suspension cultures of Acer pseudoplatanous, found that the concentration of 2, 4-D in the medium controlled cell division. It seems unlikely that the concetration...), but this concentration was inhibitory, producing masses of hard dark green callus and minimal shoot initiation. These results are consistent with work on other woody species including Acer (Preece et al. , 1991) and white ash (Bates et al. , 1992). A minimum exposure...

Chanon, Ann Marie

1993-01-01

94

Reciprocal Inhibitory Connections and Network  

E-print Network

(IPSCs) in RTN neurons are medi- ated by the major inhibitory neurotransmitter, -aminobutyric acidReciprocal Inhibitory Connections and Network Synchrony in the Mammalian Thalamus Molly M. Huntsman in relay cells. In addition, oscillatory synchrony was dramatically intensified. Thus, recurrent inhibitory

Huguenard, John R.

95

Inhibitory effects of urine on the polymerase chain reaction for cytomegalovirus DNA  

Microsoft Academic Search

The inhibitory effects of urine samples taken from neonates and older children, some of which were known to be infected with cytomegalovirus, on the polymerase chain reaction (PCR) were investigated. Urea was the major inhibitory component of urine and inhibited the PCR at a concentration of more than 50 mM. Urine samples from older children were more inhibitory than those

G Khan; H O Kangro; P J Coates; R B Heath

1991-01-01

96

Phytochemical screening and evaluation of in vitro angiotensin-converting enzyme inhibitory activity of Artocarpus altilis leaf.  

PubMed

This study investigates the effect of Artocarpus altilis leaf extracts on angiotensin-converting enzyme (ACE) activity. Among the extracts tested, hot ethanol extract exhibited a potent ACE-inhibitory activity with an IC?? value of 54.08?±?0.29?µg?mL?ą followed by cold ethyl acetate extract (IC?? of 85.44?±?0.85?µg?mL?ą). In contrast, the hot aqueous extracts showed minimum inhibition with the IC?? value of 765.52?±?11.97?µg?mL?ą at the maximum concentration tested. Further, the phytochemical analysis indicated the varied distribution of tannins, phenolics, glycosides, saponins, steroids, terpenoids and anthraquinones in cold and hot leaf extracts. The correlation between the phytochemical analysis and ACE-inhibitory activity suggests that the high content of glycosidic and phenolic compounds could be involved in exerting ACE-inhibitory activity. In conclusion, this study supports the utilisation of A. altilis leaf in the folk medicine for the better treatment of hypertension. Further studies on isolation and characterisation of specific ACE-inhibitory molecule(s) from ethyl acetate, ethanol and methanol extracts of A. altilis leaf would be highly interesting. PMID:21756104

Siddesha, Jalahalli M; Angaswamy, Nataraju; Vishwanath, Bannikuppe S

2011-12-01

97

Marine-Derived Quorum-Sensing Inhibitory Activities Enhance the Antibacterial Efficacy of Tobramycin against Pseudomonas aeruginosa.  

PubMed

Bacterial epiphytes isolated from marine eukaryotes were screened for the production of quorum sensing inhibitory compounds (QSIs). Marine isolate KS8, identified as a Pseudoalteromonas sp., was found to display strong quorum sensing inhibitory (QSI) activity against acyl homoserine lactone (AHL)-based reporter strains Chromobacterium violaceum ATCC 12472 and CV026. KS8 supernatant significantly reduced biofilm biomass during biofilm formation (-63%) and in pre-established, mature P. aeruginosa PAO1 biofilms (-33%). KS8 supernatant also caused a 0.97-log reduction (-89%) and a 2-log reduction (-99%) in PAO1 biofilm viable counts in the biofilm formation assay and the biofilm eradication assay respectively. The crude organic extract of KS8 had a minimum inhibitory concentration (MIC) of 2 mg/mL against PAO1 but no minimum bactericidal concentration (MBC) was observed over the concentration range tested (MBC > 16 mg/mL). Sub-MIC concentrations (1 mg/mL) of KS8 crude organic extract significantly reduced the quorum sensing (QS)-dependent production of both pyoverdin and pyocyanin in P. aeruginosa PAO1 without affecting growth. A combinatorial approach using tobramycin and the crude organic extract at 1 mg/mL against planktonic P. aeruginosa PAO1 was found to increase the efficacy of tobramycin ten-fold, decreasing the MIC from 0.75 to 0.075 µg/mL. These data support the validity of approaches combining conventional antibiotic therapy with non-antibiotic compounds to improve the efficacy of current treatments. PMID:25546516

Busetti, Alessandro; Shaw, George; Megaw, Julianne; Gorman, Sean P; Maggs, Christine A; Gilmore, Brendan F

2014-01-01

98

Marine-Derived Quorum-Sensing Inhibitory Activities Enhance the Antibacterial Efficacy of Tobramycin against Pseudomonas aeruginosa  

PubMed Central

Bacterial epiphytes isolated from marine eukaryotes were screened for the production of quorum sensing inhibitory compounds (QSIs). Marine isolate KS8, identified as a Pseudoalteromonas sp., was found to display strong quorum sensing inhibitory (QSI) activity against acyl homoserine lactone (AHL)-based reporter strains Chromobacterium violaceum ATCC 12472 and CV026. KS8 supernatant significantly reduced biofilm biomass during biofilm formation (?63%) and in pre-established, mature P. aeruginosa PAO1 biofilms (?33%). KS8 supernatant also caused a 0.97-log reduction (?89%) and a 2-log reduction (?99%) in PAO1 biofilm viable counts in the biofilm formation assay and the biofilm eradication assay respectively. The crude organic extract of KS8 had a minimum inhibitory concentration (MIC) of 2 mg/mL against PAO1 but no minimum bactericidal concentration (MBC) was observed over the concentration range tested (MBC > 16 mg/mL). Sub-MIC concentrations (1 mg/mL) of KS8 crude organic extract significantly reduced the quorum sensing (QS)-dependent production of both pyoverdin and pyocyanin in P. aeruginosa PAO1 without affecting growth. A combinatorial approach using tobramycin and the crude organic extract at 1 mg/mL against planktonic P. aeruginosa PAO1 was found to increase the efficacy of tobramycin ten-fold, decreasing the MIC from 0.75 to 0.075 µg/mL. These data support the validity of approaches combining conventional antibiotic therapy with non-antibiotic compounds to improve the efficacy of current treatments. PMID:25546516

Busetti, Alessandro; Shaw, George; Megaw, Julianne; Gorman, Sean P.; Maggs, Christine A.; Gilmore, Brendan F.

2014-01-01

99

Selection of antibiotic resistance at very low antibiotic concentrations.  

PubMed

Human use of antibiotics has driven the selective enrichment of pathogenic bacteria resistant to clinically used drugs. Traditionally, the selection of resistance has been considered to occur mainly at high, therapeutic levels of antibiotics, but we are now beginning to understand better the importance of selection of resistance at low levels of antibiotics. The concentration of an antibiotic varies in different body compartments during treatment, and low concentrations of antibiotics are found in sewage water, soils, and many water environments due to natural production and contamination from human activities. Selection of resistance at non-lethal antibiotic concentrations (below the wild-type minimum inhibitory concentration) occurs due to differences in growth rate at the particular antibiotic concentration between cells with different tolerance levels to the antibiotic. The minimum selective concentration for a particular antibiotic is reached when its reducing effect on growth of the susceptible strain balances the reducing effect (fitness cost) of the resistance determinant in the resistant strain. Recent studies have shown that resistant bacteria can be selected at concentrations several hundred-fold below the lethal concentrations for susceptible cells. Resistant mutants selected at low antibiotic concentrations are generally more fit than those selected at high concentrations but can still be highly resistant. The characteristics of selection at low antibiotic concentrations, the potential clinical problems of this mode of selection, and potential solutions will be discussed. PMID:24694026

Sandegren, Linus

2014-05-01

100

Minimum complexity density estimation  

Microsoft Academic Search

The authors introduce an index of resolvability that is proved to bound the rate of convergence of minimum complexity density estimators as well as the information-theoretic redundancy of the corresponding total description length. The results on the index of resolvability demonstrate the statistical effectiveness of the minimum description-length principle as a method of inference. The minimum complexity estimator converges to

Andrew R. Barron; Thomas M. Cover

1991-01-01

101

Chicken plasma protein: Proteinase inhibitory activity and its effect on surimi gel properties  

Microsoft Academic Search

The inhibitory activity of chicken plasma protein (CPP) at different concentrations on sarcoplasmic proteinases and autolysis of mince and washed mince of bigeye snapper and lizardfish was investigated. CPP (0–2% w\\/w) exhibited inhibitory activity toward sarcoplasmic proteinases and autolysis, especially when CPP concentration increased. Electrophoretic study revealed that CPP effectively prevented the degradation of myosin heavy chain (MHC) in mince

Saroat Rawdkuen; Soottawat Benjakul; Wonnop Visessanguan; Tyre C. Lanier

2004-01-01

102

42 CFR 84.104 - Gas tightness test; minimum requirements.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Gas tightness test; minimum requirements. 84...Apparatus § 84.104 Gas tightness test; minimum requirements. ...(b) Six persons will each wear the apparatus in the test concentrations specified in...

2010-10-01

103

Concentration-dependent stimulatory and inhibitory effect of troglitazone on insulin-induced fatty acid synthase expression and protein kinase B activity in 3T3-L1 adipocytes.  

PubMed

In order to study the effect of the peroxisome proliferator-activated receptor gamma (PPARgamma) agonist troglitazone on the insulin-induced expression of fatty acid synthase (FAS) in adipocytes, we generated a 3T3-L1 cell line stably expressing a FAS reporter gene construct. In this cell line, a low concentration of troglitazone (250 nM) increased the effect of insulin on the FAS promoter activity and the expression of FAS protein about 1.5- to 2-fold. Since the effect of insulin on the expression of FAS is believed to be mediated by activation of protein kinase B (PKB), we investigated the effect of troglitazone on the regulation of PKB. Troglitazone (250 nM) increased the maximal effect of insulin on PKB activity about twofold without significantly affecting its EC(50) (1.4+/-0.5 nM vs. 2.2+/-0.6 nM in controls). Higher concentrations of troglitazone (> or =1 microM) inhibited both insulin-stimulated PKB activity and expression of FAS. In summary, our data indicate a dual effect of troglitazone on the insulin-induced FAS gene expression in 3T3-L1 cells. The therapeutic, stimulatory effect is produced by low concentrations of troglitazone (250 nM), and is presumably mediated by enhanced activation of PKB. PMID:11919653

Barthel, Andreas; Krüger, Klaus-Dieter; Roth, Richard A; Joost, Hans-Georg

2002-04-01

104

Acetylcholinesterase inhibitory activity and chemical composition of commercial essential oils.  

PubMed

Commercially available essential oils extracted from Artemisia dracunculus L., Inula graveolens L., Lavandula officinalis Chaix, and Ocimum sanctum L. and the components of these oils were screened by the microplate assay method for determining their acetylcholinesterase (AChE) inhibitory activity. The composition profiles of the oils were characterized by gas chromatography-mass spectrometry (GC-MS) analysis, and the relationships between the oil components and the AChE inhibitory activity of the oils were outlined. The results showed that all of the oils, except that of A. dracunculus from Hungary, exhibited AChE inhibitory activity, and the A. dracunculus oil from France showed the most potent inhibitory activity [50% inhibition concentration (IC(50)) = 0.058 mg/mL]. The AChE inhibitory activity of I. graveolens oil has not been reported to date, and this study is the first to reveal this activity in the oil. Among the essential oil components, five components, namely, 1,8-cineole, ?-pinene, eugenol, ?-terpineol, and terpinen-4-ol, showed AChE inhibitory activity, with IC(50) values of 0.015, 0.022, 0.48, 1.3, and 3.2 mg/mL, respectively. Eugenol, in particular, was found to be a potent AChE inhibitor along with determination of the IC(50) value, a finding that has been reported for the first time in this study. However, the ratio of the contribution of the active components, including a novel AChE inhibitor, to the observed AChE inhibitory activity of the essential oils was not very high. The results of this study raise concerns about the AChE inhibitory activity of widely produced and readily accessible commercial essential oils. PMID:19358605

Dohi, Satomi; Terasaki, Masanori; Makino, Masakazu

2009-05-27

105

ORIGINAL PAPER Antioxidant and angiotensin-converting enzyme inhibitory  

E-print Network

ORIGINAL PAPER Antioxidant and angiotensin-converting enzyme inhibitory activity of yoghurt calcium caseinate (SCC) and whey protein concentrate (WPC) on the antioxidant and angiotensin, SCC, and WPC at 2% and 4% ratios. The antioxidant activity was determined using 2,2,-diphenyl-1

Paris-Sud XI, Université de

106

Targeting inhibitory neurotransmission in tinnitus  

PubMed Central

Tinnitus perception depends on the presence of its neural correlates within the auditory neuraxis and associated structures. Targeting specific circuits and receptors within the central nervous system in an effort to relieve the perception of tinnitus and its impact on one’s emotional and mental state has become a focus of tinnitus research. One approach is to upregulate endogenous inhibitory neurotransmitter levels (e.g. glycine and GABA) and selectively target inhibitory receptors in key circuits to normalize tinnitus pathophysiology. Thus, the basic functional and molecular properties of two major ligand-gated inhibitory receptor systems, the GABAA receptor (GABAAR) and glycine receptor (GlyR) are described. Also reviewed is the rationale for targeting inhibition which stems from reported tinnitus-related homeostatic plasticity of inhibitory neurotransmitter systems and associated enhanced neuronal excitability throughout most central auditory structures. However, the putative role of the medial geniculate body (MGB) in tinnitus has not been previously addressed, specifically in terms of its inhibitory afferents from inferior colliculus and thalamic reticular nucleus and its GABAAR functional heterogeneity. This heterogeneous population of GABAARs, which may be altered in tinnitus pathology, and its key anatomical position in the auditory CNS make the MGB a compelling structure for tinnitus research. Finally, some selective compounds, which enhance tonic inhibition, have successfully ameliorated tinnitus in animal studies, suggesting that the MGB and, to a lesser degree, the auditory cortex may be their primary locus of action. These pharmacological interventions are examined, in terms of their mechanism of action and why these agents, may be effective in tinnitus treatment. PMID:22405692

Richardson, Ben D.; Brozoski, Thomas J.; Ling, Lynne L.; Caspary, Donald M.

2012-01-01

107

Ozone Minimums, 1979 to 2013 - Duration: 0:32.  

NASA Video Gallery

Minimum concentration of ozone in the southern hemisphere for each year from 1979-2013 (there is no data from 1995). Each image is the day of the year with the lowest concentration of ozone. A grap...

108

Antifungal susceptibility and growth inhibitory response of oral Candida species to Brucea javanica Linn. extract  

PubMed Central

Background Candida species have been associated with the emergence of resistant strains towards selected antifungal agents. Plant products have been used traditionally as alternative medicine to ease candidal infections. The present study was undertaken to investigate the antifungal susceptibility patterns and growth inhibiting effect of Brucea javanica seeds extract against Candida species. Methods A total of seven Candida strains that includes Candida albicans ATCC14053, Candida dubliniensis ATCCMYA-2975, Candida glabrata ATCC90030, Candida krusei ATCC14243, Candida lusitaniae ATCC64125, Candida parapsilosis ATCC22019 and Candida tropicalis ATCC13803 were used in this study. The antifungal activity, minimum inhibitory concentration and minimum fungicidal concentration of B. javanica extract were evaluated. Each strain was cultured in Yeast Peptone Dextrose broth under four different growth environments; (i) in the absence and presence of B. javanica extract at respective concentrations of (ii) 1 mg/ml (iii) 3 mg/ml and (iv) 6 mg/ml. The growth inhibitory responses of the candidal cells were determined based on changes in the specific-growth rates (?) and doubling time (g). The values in the presence of extract were computed as percentage in the optical density relative to that of the total cells suspension in the absence of extract. Results B. javanica seeds extract exhibited antifungal properties. C. tropicalis showed the highest growth rate; 0.319?±?0.002 h-1, while others were in the range of 0.141?±?0.001 to 0.265?±?0.005 h-1. In the presence of extract, the lag and log phases were extended and deviated the ?- and g-values. B. javanica extract had significantly reduced the ?-values of C. dubliniensis, C. krusei and C. parapsilosis at more than 80% (??

2013-01-01

109

MINIMUM SECURITY REQUIREMENTS FOR FEDERAL  

E-print Network

March 2006 MINIMUM SECURITY REQUIREMENTS FOR FEDERAL INFORMATION AND INFORMATION SYSTEMS: FEDERAL of government information and information systems. FIPS 200, Minimum Security Requirements for Federal and information systems. FIPS 200, Minimum Security Requirements for Federal Information and Information Systems

110

Penicillin concentrations in cerebrospinal fluid after different treatment regimens for syphilis.  

PubMed Central

The concentrations of penicillin in the cerebrospinal fluid (CSF) were compared simultaneously with those in the serum in 17 patients with syphilis. The antibiotic concentrations were measured by the agar well diffusion method. There were no detectable concentrations of penicillin in the CSF after administration of benzathine penicillin 2.4 megaunits, benzathine penicillin 7.2 megaunits, procaine penicillin in aluminium monostearate (PAM) 12 megaunits, or aqueous procaine penicillin G 2.4 megaunits. Only after high doses of aqueous penicillin G 24 megaunits daily or aqueous penicillin G 2 megaunits daily together with oral probenecid 2 g daily was penicillin detectable in the CSF. The concentrations after the latter regimen were the highest and much higher than the minimum inhibitory concentration for Treponema pallidum. PMID:7448578

Polnikorn, N; Witoonpanich, R; Vorachit, M; Vejjajiva, S; Vejjajiva, A

1980-01-01

111

Cortical neurodynamics of inhibitory control.  

PubMed

The ability to inhibit prepotent responses is critical for successful goal-directed behaviors. To investigate the neural basis of inhibitory control, we conducted a magnetoencephalography study where human participants performed the antisaccade task. Results indicated that neural oscillations in the prefrontal cortex (PFC) showed significant task modulations in preparation to suppress saccades. Before successfully inhibiting a saccade, beta-band power (18-38 Hz) in the lateral PFC and alpha-band power (10-18 Hz) in the frontal eye field (FEF) increased. Trial-by-trial prestimulus FEF alpha-band power predicted successful saccadic inhibition. Further, inhibitory control enhanced cross-frequency amplitude coupling between PFC beta-band (18-38 Hz) activity and FEF alpha-band activity, and the coupling appeared to be initiated by the PFC. Our results suggest a generalized mechanism for top-down inhibitory control: prefrontal beta-band activity initiates alpha-band activity for functional inhibition of the effector and/or sensory system. PMID:25031398

Hwang, Kai; Ghuman, Avniel S; Manoach, Dara S; Jones, Stephanie R; Luna, Beatriz

2014-07-16

112

Cortical Neurodynamics of Inhibitory Control  

PubMed Central

The ability to inhibit prepotent responses is critical for successful goal-directed behaviors. To investigate the neural basis of inhibitory control, we conducted a magnetoencephalography study where human participants performed the antisaccade task. Results indicated that neural oscillations in the prefrontal cortex (PFC) showed significant task modulations in preparation to suppress saccades. Before successfully inhibiting a saccade, beta-band power (18–38 Hz) in the lateral PFC and alpha-band power (10–18 Hz) in the frontal eye field (FEF) increased. Trial-by-trial prestimulus FEF alpha-band power predicted successful saccadic inhibition. Further, inhibitory control enhanced cross-frequency amplitude coupling between PFC beta-band (18–38 Hz) activity and FEF alpha-band activity, and the coupling appeared to be initiated by the PFC. Our results suggest a generalized mechanism for top-down inhibitory control: prefrontal beta-band activity initiates alpha-band activity for functional inhibition of the effector and/or sensory system. PMID:25031398

Ghuman, Avniel S.; Manoach, Dara S.; Jones, Stephanie R.; Luna, Beatriz

2014-01-01

113

The Minimum Price Contract  

E-print Network

, he can Mark Waller, Steve Amosson, Mark Welch, and Kevin Dhuyvetter* 2 lock in a floor price and still have upside poten- tial if the market rallies. Options-based marketing strategies, such as the minimum price contract, work well in times...

Waller, Mark L.; Amosson, Stephen H.; Welch, Mark; Dhuyvetter, Kevin C.

2008-10-17

114

Inhibitory effect of linalool-rich essential oil from Lippia alba on the peptidase and keratinase activities of dermatophytes.  

PubMed

Abstract Lippia alba (Miller) N.E. Brown is an aromatic plant known locally as "Erva-cidreira-do-campo" that has great importance in Brazilian folk medicine. The aim of our study was to evaluate the antidermatophytic potential of linalool-rich essential oil (EO) from L. alba and analyze the ability of this EO to inhibit peptidase and keratinase activities, which are important virulence factors in dermatophytes. The minimum inhibitory concentrations (MICs) of L. alba EO were 39, 156 and 312 µg/mL against Trichophyton rubrum, Epidermophyton floccosum and Microsporum gypseum, respectively. To evaluate the influence of L. alba EO on the proteolytic and keratinolytic activities of these dermatophytes, specific inhibitory assays were performed. The results indicated that linalool-rich EO from L. alba inhibited the activity of proteases and keratinases secreted from dermatophytes, and this inhibition could be a possible mechanism of action against dermatophytes. Due to the effective antidermatophytic activity of L. alba EO, further experiments should be performed to explore the potential of this linalool-rich EO as an alternative antifungal therapy. PMID:23323991

Costa, Danielle Cristina Machado; Vermelho, Alane Beatriz; Almeida, Catia Amancio; de Souza Dias, Edilma Paraguai; Cedrola, Sabrina Martins Lage; Arrigoni-Blank, Maria de Fátima; Blank, Arie Fitzgerald; Alviano, Celuta Sales; Alviano, Daniela Sales

2014-02-01

115

Inhibitory effects of Thai plants ?-glycosides on Trichomonas vaginalis  

Microsoft Academic Search

Trichomoniasis is now an important health problem in developing countries. Although metronidazole has so far been widely used\\u000a to treat this disease, the prevalence of metronidazole-resistant protozoa and unpleasant adverse effects have been found.\\u000a In this study, natural products purified from Thai plants were, therefore, investigated for their effectiveness against Trichomonas vaginalis. The minimal inhibitory concentrations for all ?-glycosides against

Dumrongkiet Arthan; Somphong Sithiprom; Kanthinich Thima; Chutima Limmatvatirat; Porntip Chavalitshewinkoon-Petmitr; Jisnuson Svasti

2008-01-01

116

Cortical Plasticity Induced by Inhibitory Neuron Transplantation  

PubMed Central

Critical periods are times of pronounced brain plasticity. During a critical period in the postnatal development of the visual cortex, the occlusion of one eye triggers a rapid reorganization of neuronal responses, a process known as ocular dominance plasticity. We have shown that the transplantation of inhibitory neurons induces ocular dominance plasticity after the critical period. Transplanted inhibitory neurons receive excitatory synapses, make inhibitory synapses onto host cortical neurons, and promote plasticity when they reach a cellular age equivalent to that of endogenous inhibitory neurons during the normal critical period. These findings suggest that ocular dominance plasticity is regulated by the execution of a maturational program intrinsic to inhibitory neurons. By inducing plasticity, inhibitory neuron transplantation may facilitate brain repair. PMID:20185728

Southwell, Derek G.; Froemke, Robert C.; Alvarez-Buylla, Arturo; Stryker, Michael P.; Gandhi, Sunil P.

2011-01-01

117

INHIBITORY EFFECT OF HEPARIN ON HERPES SIMPLEX VIRUS1  

PubMed Central

Nahmias, André J. (Boston University School of Medicine, Boston, Mass.), and Sidney Kibrick. Inhibitory effect of heparin on herpes simplex virus. J. Bacteriol. 87:1060–1066. 1964.—A substance inhibitory to herpes simplex virus was observed during experiments with leukocyte cultures. The component in the cultures responsible for this inhibition was identified as heparin. The minimal inhibitory concentration required to inhibit 30 to 300 tcd50 of the virus in human amnion tissue culture was found to be 1 to 2 units per ml (10 to 20 ?g/ml). This effect was confirmed with other strains of herpes simplex virus, other tissue-culture systems, and other media. The inhibitory activity of the heparin was found to be related to the sulfate groupings on the molecule. The effect of heparin appears to be on the virus, rather than on the cell. The virus is not inactivated, however, and the heparin-virus “complex” is readily dissociable on dilution. Heparin was shown to affect viral infection in its earliest phase, probably at the primary electrostatic attachment of virus to cell. The import of these and related observations on common virological laboratory procedures and the possible biological significance of our findings are discussed. PMID:4289440

Nahmias, André J.; Kibrick, Sidney

1964-01-01

118

Investigation of the antibacterial activity and efflux pump inhibitory effect of co-loaded piperine and gentamicin nanoliposomes in methicillin-resistant Staphylococcus aureus.  

PubMed

Abstract Objective: Antibiotic resistance has stimulated the research for developing novel strategies that can prevent bacterial growth. Methicillin-resistant Staphylococcus aureus (MRSA), regarded as one of the most serious antibiotic-resistant bacteria which has been conventionally recognized as a nosocomial pathogen. Materials and methods: Nanoliposomal formulations of piperine and gentamicin were prepared by dehydration-rehydration (DRV) method and characterized for size, zeta potential and encapsulation efficiency. Antibactericidal activities of liposomal and free forms were evaluated against MRSA ATCC 43300 by the determination of minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and fractional inhibitory concentration index (FICI). The time-kill studies were carried out to evaluate the potency of antibacterial agents. The effect of piperine on bacterial efflux pumps was also investigated. Results: MIC values of gentamicin and piperine were 32 and 100?µg/mL, respectively. Synergetic effects were observed by the combination of gentamicin and piperine and FICI was determined to be 0.5. Following incorporation of gentamicin into liposomal gentamicin and liposomal combination, the MIC values were reduced 16- and 32-fold, respectively. MBC values of gentamicin reduced 4 and 8 times following incorporation into gentamicin and combination liposomes, respectively. In comparison with vancomycin, liposomal combination was more effective in bacterial inhibition and killing. Liposomal combination was the most effective preparations in time-kill study. Our findings indicated that liposomal piperine was able to inhibit the efflux pump sufficiently. Conclusion: The results of this study revealed that liposomal combination is a powerful nano-antibacterial agent to eradicate MRSA infection. This dual-loaded formulation was an effective approach for eradication of MRSA. PMID:24842547

Khameneh, Bahman; Iranshahy, Milad; Ghandadi, Morteza; Ghoochi Atashbeyk, Davod; Fazly Bazzaz, Bibi Sedigheh; Iranshahi, Mehrdad

2014-05-20

119

Minimum Common String Partition Parameterized  

E-print Network

Minimum Common String Partition Parameterized Peter Damaschke Department of Computer Science and Engineering Chalmers University, 41296 G¨oteborg, Sweden ptr@cs.chalmers.se Abstract. Minimum Common String occurences in x. In the Minimum Common String Partition (MCSP) problem, two strings x, y of length n

Damaschke, Peter

120

Inhibitory effect of Allium sativum and Zingiber officinale extracts on clinically important drug resistant pathogenic bacteria  

PubMed Central

Background Herbs and spices are very important and useful as therapeutic agent against many pathological infections. Increasing multidrug resistance of pathogens forces to find alternative compounds for treatment of infectious diseases. Methods In the present study the antimicrobial potency of garlic and ginger has been investigated against eight local clinical bacterial isolates. Three types of extracts of each garlic and ginger including aqueous extract, methanol extract and ethanol extract had been assayed separately against drug resistant Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus, Klebsiella pneumoniae, Shigella sonnei, Staphylococcusepidermidis and Salmonella typhi. The antibacterial activity was determined by disc diffusion method. Results All tested bacterial strains were most susceptible to the garlic aqueous extract and showed poor susceptibility to the ginger aqueous extract. The (minimum inhibitory concentration) MIC of different bacterial species varied from 0.05?mg/ml to 1.0?mg/ml. Conclusion In the light of several socioeconomic factors of Pakistan mainly poverty and poor hygienic condition, present study encourages the use of spices as alternative or supplementary medicine to reduce the burden of high cost, side effects and progressively increasing drug resistance of pathogens. PMID:22540232

2012-01-01

121

Inhibitory effects of essential oils of medicinal plants from growth of plant pathogenic fungi.  

PubMed

Plant cells produce a vast amount of secondary metabolites. Production of some compounds is restricted to a single species. Some compounds are nearly always found only in certain specific plant organs and during a specific developmental period of the plant. Some secondary metabolites of plants serve as defensive compounds against invading microorganisms. Nowadays, it is attempted to substitute the biological and natural agents with chemically synthesized fungicides. In the present research, the antifungal activities of essential oils of seven medicinal plants on mycelial growth of three soilborne plant pathogenic fungi were investigated. The plants consisted of Zataria multiflora, Thymus carmanicus, Mentha pieperata, Satureja hortensis, Lavandual officinolis, Cuminum cyminum and Azadirachta indica. The first five plants are from the family Labiatae. Examined fungi, Fusarium oxysporum f.sp. lycopersici, Fusarium solani and Rhizoctonia solani are the causal agents of tomato root rot. Essential oils of Z. multiflora, T. carmanicus, M. pieperata, S. hortensis and C. cyminum were extracted by hydro-distillation method. Essential oils of L. officinalis and A. indica were extracted by vapor-distillation method. A completely randomized design with five replicates was used to examine the inhibitory impact of each concentration (300, 600 and 900 ppm) of each essential oil. Poisoned food assay using potato dextrose agar (PDA) medium was employed. Results showed that essential oils of A. indica, Z. multiflora, T. carmanicus and S. hortensis in 900 ppm at 12 days post-inoculation, when the control fungi completely covered the plates, prevented about 90% from mycelial growth of each of the fungi. While, the essential oils of M. pieperata, C. cyminum and L. officinalis in the same concentration and time prevented 54.86, 52.77 and 48.84%, respectively, from F. solani growth. These substances did not prevent from F. oxysporum f.sp. lycopersici and R. solani growth. Minimum inhibitory concentration (MIC) of essential oils of T. carmanicus, Z. multiflora and A. indica from R. solani and F. solani growth was 900 and 600 ppm, respectively. In addition, the MIC of essential oils of these plants and essential oil of S. hortensis from F. oxysporum f.sp. lycopersici growth was 900 ppm. The MIC of essential oils of M. pieperata, C. cyminum and L. officinalis from F. solani growth was 900 ppm. PMID:22702190

Panjehkeh, N; Jahani Hossein-Abadi, Z

2011-01-01

122

Inhibitory activity of Syzygium aromaticum and Cymbopogon citratus (DC.) Stapf. essential oils against Listeria monocytogenes inoculated in bovine ground meat  

PubMed Central

This research evaluated the antimicrobial effect of the clove (Syzygium aromaticum) and lemongrass (Cymbopogon citratus (DC.) Stapf.) essential oils (EOs) against Listeria monocytogenes ATCC 19117 growth added to bovine ground meat stored under refrigeration (5 ± 2 °C) for three days. The EOs, extracted by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS), were tested in vitro using an agar well diffusion methodology for determination of Minimum Inhibitory Concentration (MIC). The MIC concentrations for both essential oils on culture tested of L. monocytogenes were 1.56%. The EOs concentrations applied in contaminated ground beef were 1.56, 3.125 and 6.25% (w/v) based on MIC levels and possible activity reductions by food constituents. The bacteria populations were significantly reduced (p ? 0.05) after one day of storage in ground meat samples treated with clove and lemongrass EOs at concentrations of 1.56%. There were no significant counts of L. monocytogenes in samples at the other concentrations of the two oils applied after the second day of storage. The sensory acceptability evaluation of the bovine ground meat samples treated with EOs showed that the addition at concentrations higher than 1.56% promote undesirable alterations of taste, odor and characteristic color. The application of EOs at low concentrations in food products can be used in combination with other preservation methods, such as refrigeration, to control pathogens and spoilage bacteria during shelf-life; which goes according to current market trends, where consumers are requesting natural products. PMID:24294222

de Oliveira, Thales Leandro Coutinho; das Graças Cardoso, Maria; de Araújo Soares, Rodrigo; Ramos, Eduardo Mendes; Piccoli, Roberta Hilsdorf; Tebaldi, Victor Maximiliano Reis

2013-01-01

123

Design for Minimum Risk  

NASA Technical Reports Server (NTRS)

Design for Minimum Risk (DFMR) is a term used by NASA programs as an expansion of the general hazard reduction process where if an identified hazard cannot be eliminated, the design is modified to reduce the associated mishap risk to an acceptable level. DFMR is a set of specific requirements to minimize risk. DFMR is not well understood and there are many misconceptions concerning the meaning and use. This paper will provide insight into the use of DFMR for space applications; it s comparison to other hazard mitigation strategies and examples of how the approach has been used in the past. It will also highlight documents used by NASA on various programs to determine DFMR.

Wetherholt, Jon; Heimann, Timothy J.

2010-01-01

124

Probing inhibitory effects of nanocrystalline cellulose: inhibition versus surface charge.  

PubMed

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 (ECIS(50)), 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. PMID:22252333

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

2012-02-21

125

Probing inhibitory effects of nanocrystalline cellulose: inhibition versus surface charge  

NASA Astrophysics Data System (ADS)

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.

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

2012-02-01

126

In glucose-limited continuous culture the minimum substrate concentration for growth, smin, is crucial in the competition between the enterobacterium Escherichia coli and Chelatobacter heintzii, an environmentally abundant bacterium  

PubMed Central

The competition for glucose between Escherichia coli ML30, a typical copiotrophic enterobacterium and Chelatobacter heintzii ATCC29600, an environmentally successful strain, was studied in a carbon-limited culture at low dilution rates. First, as a base for modelling, the kinetic parameters ?max and Ks were determined for growth with glucose. For both strains, ?max was determined in batch culture after different precultivation conditions. In the case of C. heintzii, ?max was virtually independent of precultivation conditions. When inoculated into a glucose-excess batch culture medium from a glucose-limited chemostat run at a dilution rate of 0.075?h?1 C. heintzii grew immediately with a ?max of 0.17±0.03?h?1. After five transfers in batch culture, ?max had increased only slightly to 0.18±0.03?h?1. A different pattern was observed in the case of E. coli. Inoculated from a glucose-limited chemostat at D=0.075?h?1 into glucose-excess batch medium E. coli grew only after an acceleration phase of ?3.5?h with a ?max of 0.52?h?1. After 120 generations and several transfers into fresh medium, ?max had increased to 0.80±0.03?h?1. For long-term adapted chemostat-cultivated cells, a Ks for glucose of 15??g?l?1 for C. heintzii, and of 35??g?l?1 for E. coli, respectively, was determined in 14C-labelled glucose uptake experiments. In competition experiments, the population dynamics of the mixed culture was determined using specific surface antibodies against C. heintzii and a specific 16S rRNA probe for E. coli. C. heintzii outcompeted E. coli in glucose-limited continuous culture at the low dilution rates of 0.05 and 0.075?h?1. Using the determined pure culture parameter values for Ks and ?max, it was only possible to simulate the population dynamics during competition with an extended form of the Monod model, which includes a finite substrate concentration at zero growth rate (smin). The values estimated for smin were dependent on growth rate; at D=0.05?h?1, it was 12.6 and 0??g?l?1 for E. coli and C. heintzii, respectively. To fit the data at D=0.075?h?1, smin for E. coli had to be raised to 34.9??g?l?1 whereas smin for C. heintzii remained zero. The results of the mathematical simulation suggest that it is not so much the higher Ks value, which is responsible for the unsuccessful competition of E. coli at low residual glucose concentration, but rather the existence of a significant smin. PMID:22030672

Füchslin, Hans Peter; Schneider, Christian; Egli, Thomas

2012-01-01

127

Crude ethanolic extracts of Garcinia kola seeds Heckel (Guttiferae) prolong the lag phase of Helicobacter pylori: inhibitory and bactericidal potential.  

PubMed

Problems associated with current treatment regimens have generated a considerable interest in alternative approaches for the eradication of Helicobacter pylori infections using phytochemical compounds. In an attempt to identify potential sources of such compounds, the antimicrobial activity of five solvent extracts of Garcinia kola seeds were investigated against 30 clinical strains of H. pylori and a standard control strain, NCTC 11638, using standard microbiological techniques. Metronidazole and amoxicillin were included in these experiments as positive control antibiotics. All the extracts tested exhibited anti-H. pylori activity with zone diameters of inhibition between 0 and 25 mm. The ethanol extract demonstrated considerable anti-H. pylori activity with a percentage susceptibility of 53.3% and minimum inhibitory concentration for 50% susceptibility (MIC??) values ranging from 0.63 to 5.0 mg/mL. Ranges of MIC?? values for amoxicillin and metronidazole were 0.01-0.63 mg/mL and 0.04-5.0 mg/mL, respectively. The inhibitory activity of the ethanol extract was similar to that of metronidazole (P?>?.05) as opposed to amoxicillin (P?concentration was doubled and quadrupled alongside a killing rate of 80.1% and 93.7%, respectively, after 24 hours and of 100% after 30 hours. These results demonstrate that the ethanol extract of G. kola may contain therapeutically useful compounds against H. pylori. PMID:21476930

Njume, Collise; Afolayan, Anthony J; Clarke, Anna M; Ndip, Roland N

2011-01-01

128

Sitafloxacin: Antimicrobial activity against ciprofloxacin-selected laboratory mutants of Mycoplasma genitalium and inhibitory activity against its DNA gyrase and topoisomerase IV.  

PubMed

A sitafloxacin regimen is highly effective on Mycoplasma genitalium infections, including those caused by the mycoplasmas harboring mutant topoisomerase IV with a quinolone resistance-associated amino acid change in ParC. In this study, we evaluated sitafloxacin antimicrobial activities against M. genitalium, including the mycolasmas with decreased susceptibilities to quinolones, by determining minimum inhibitory concentrations (MICs) for the strain ATCC 33530 and its 3 ciprofloxacin-selected mutants, for which ciprofloxacin MICs were 8-16 times higher than that for their parent strain. We also evaluated inhibitory activities against the target enzymes of M. genitalium by determining concentrations required to inhibit 50% (IC50) of the supercoiling activity of the recombinant wild-type DNA gyrase and the decatenating activities of the recombinant wild-type topoisomerase IV and the 2 types of mutant topoisomerase IV with a single amino acid change in ParC. Sitafloxacin MICs were 0.125 for the parent strain and 0.125-0.25 ?g/ml for the mutants. Sitafloxacin IC50s were 3.12 for the supercoiling activity of the wild-type DNA gyrase and 2.98 ?g/ml for the decatenating activity of the wild-type topoisomerase IV. Its IC50s for the decatenating activity of the mutant topoisomerase IV harboring an amino acid change in ParC were 15.1 for Gly-81 ? Cys and 7.92 ?g/ml for Asp-87 ? Tyr. Sitafloxacin was highly active against ciprofloxacin-selected mutants of M. genitalium and possessed intense inhibitory activities not only against wild-type DNA gyrase and topoisomerase IV but also against mutant topoisomerase IV containing ParC with a quinolone resistance-associated amino acid change. Sitafloxacin could be a promising agent for M. genitalium infections. PMID:25245990

Deguchi, Takashi; Kikuchi, Mina; Yasuda, Mitsuru; Ito, Shin

2015-01-01

129

Studies of the in vitro cytotoxic, antioxidant, lipase inhibitory and antimicrobial activities of selected Thai medicinal plants  

PubMed Central

Background Traditional folk medicinal plants have recently become popular and are widely used for primary health care. Since Thailand has a great diversity of indigenous (medicinal) plant species, this research investigated 52 traditionally used species of Thai medicinal plants for their in vitro cytotoxic, antioxidant, lipase inhibitory and antimicrobial activities. Methods The 55 dried samples, derived from the medicinally used parts of the 52 plant species were sequentially extracted by hexane, dichloromethane, ethanol and water. These 220 extracts were then screened for in vitro (i) cytotoxicity against four cell lines, derived from human lung (A549), breast (MDA-MB-231), cervical (KB3-1) and colon (SW480) cancers, using the MTT cytotoxicity assay; (ii) antioxidant activity, analyzed by measuring the scavenging activity of DPPH radicals; (iii) lipase inhibitory activity, determined from the hydrolytic reaction of p-nitrophenyllaurate with pancreatic lipase; and (iv) antimicrobial activity against three Gram-positive and two Gram-negative bacteria species plus one strain of yeast using the disc-diffusion method and determination of the minimum inhibitory concentration by the broth micro-dilution assay. Results The crude dichloromethane and/or ethanol extracts from four plant species showed an effective in vitro cytotoxic activity against the human cancer cell lines that was broadly similar to that of the specific chemotherapy drugs (etoposide, doxorubicin, vinblastine and oxaliplatin). In particular, this is the first report of the strong in vitro cytotoxic activity of Bauhinia strychnifolia vines. The tested tissue parts of only six plant species (Allium sativum, Cocoloba uvifera, Dolichandrone spathacea, Lumnitzera littorea, Sonneratia alba and Sonneratia caseolaris) showed promising potential antioxidant activity, whereas lipase inhibitory activity was only found in the ethanol extract from Coscinum fenestratum and this was weak at 17-fold lower than Orlistat, a known lipase inhibitor. The highest antimicrobial activity was observed in the extracts from S. alba and S. caseolaris against Pseudomonas aeruginosa and Candida albicans, respectively. Conclusion The Thai medicinal plant B. strychnifolia is first reported to exert strong in vitro cytotoxic activities against human cancer cell lines and warrants further enrichment and characterization. The broad spectrum of the biological activities from the studied plant extracts can be applied as the guideline for the selection of Thai medicinal plant species for further pharmacological and phytochemical investigations. PMID:23145786

2012-01-01

130

Inhibitory effects of Korean plants on HIV-1 activities.  

PubMed

In the search for novel anti-human immunodeficiency virus type 1 (anti-HIV-1) agents from natural sources, 49 MeOH extracts of Korean plants were screened for their inhibitory effects against RNA-dependent DNA polymerase (RT) and ribonuclease H (RNase H) activities of HIV-1 reverse transcriptase and HIV-1 protease, and anti-HIV-1 activity. Regarding the HIV-1 reverse transcriptase, Agrimonia pilosa (whole plant), Cornus kousa (stem and leaf), Limonium tetragonum (root) and Mallotus japonicus (stem) showed significant inhibitory activity on RT activity with 50% inhibitory activity (IC(50)) of 8.9, 6.3, 7.5 and 11.9 microg/mL, respectively, whereas Agrimonia pilosa was also active against RNase H activity (IC(50) = 98.4 microg/mL). Four plants, namely Agrimonia pilosa (whole plant), Atractylodes japonica (root), Clematis heracleifolia (whole plant) and Syneilesis palmata (whole plant), were appreciably active (<35%) against recombinant HIV-1 protease at a concentration of 100 microg/mL. Crinum asiaticum var. japonicum (root) showed significant anti-HIV-1 activity (ED(50) = 12.5 microg/mL) with a favourable SI value of 16. PMID:11536375

Min, B S; Kim, Y H; Tomiyama, M; Nakamura, N; Miyashiro, H; Otake, T; Hattori, M

2001-09-01

131

Inhibitory effects of nisin and potassium sorbate alone or in combination on vegetative cells growth and spore germination of Bacillus sporothermodurans in milk.  

PubMed

The inhibitory activities of nisin or/and potassium sorbate on spores and vegetative cells of Bacillus sporothermodurans LTIS27, which are known to be a contaminant of dairy products and to be extremely heat-resistant, were investigated. First, the tested concentrations of nisin or potassium sorbate inhibited vegetative cell growth; with the minimum inhibitory concentrations were 5 × 10(3) IU/ml and 2% (w/v), respectively. Then, the behaviour of vegetative cells and spores in presence of sub-lethal concentrations of nisin (50 UI/ml) or/and potassium sorbate (0.2%), in milk at 37 °C for 5 days, were evaluated. In the absence of inhibitors, strain grew and sporulated at the end of the exponential phase. Nisin (50 UI/ml) was able to inhibit spore outgrowth but didn't affect their germination. It induced an immediate and transitory reduction (1.6log(10) after 1 h and 2.8log(10) after 6 h of incubation) of vegetative cell growth which reappeared between 10 h and 24 h. Potassium sorbate (0.2%) had a durable bacteriostatic effect (1.1log(10) after 6 h), on vegetative cells, followed by a slower regrowth. It was able to inhibit both germination and outgrowth of spores. Association of nisin and potassium sorbate, at sub-lethal concentrations, showed a synergistic effect and resulted in a total inhibition of cells growth after 5 days. The results illustrate the efficacy of nisin and potassium sorbate in combination, and the commercial potential of applying such treatment to decontaminate any product that has a problem with persistence of bacterial spores. PMID:25475264

Aouadhi, Chedia; Mejri, Slah; Maaroufi, Abderrazak

2015-04-01

132

Inhibitory neurotransmission and olfactory memory in honeybees  

Microsoft Academic Search

In insects, ?-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

Abdessalam Kacimi El Hassani; Martin Giurfa; Monique Gauthier; Catherine Armengaud

2008-01-01

133

Dynamic Capacitated Minimum Spanning Trees  

Microsoft Academic Search

Given a set of terminals, each associated with a positive number denoting the traffic to be routed to a central terminal (root), the Capacitated Minimum Spanning Tree (CMST) problem asks for a minimum spanning tree, spanning all terminals, such that the amount of traffic route d from a subtree, linked to the root by an edge, does not exceed the

Raja Jothi; Balaji Raghavachari

2004-01-01

134

Hu man minimum redundancy coding  

E-print Network

14 Hu#11;man minimum redundancy coding It has become usual to store data and transmit messages a particular coded text. In a classic paper, published in 1952, David Hu#11;man described an algorithm to #12;nd the set of codes that would minimize the expected length 175 #12; 176 Hu#11;man minimum redundancy

Jones, Geraint

135

6 CFR 27.204 - Minimum concentration by security issue.  

Code of Federal Regulations, 2010 CFR

...National Fire Protection Association (NFPA) flammability hazard rating of 4...National Fire Protection Association (NFPA) flammability hazard rating of 1, 2...flammability hazard ratings are defined in NFPA 704: Standard System for the...

2010-01-01

136

6 CFR 27.204 - Minimum concentration by security issue.  

Code of Federal Regulations, 2011 CFR

...National Fire Protection Association (NFPA) flammability hazard rating of 4...National Fire Protection Association (NFPA) flammability hazard rating of 1, 2...flammability hazard ratings are defined in NFPA 704: Standard System for the...

2011-01-01

137

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

PubMed Central

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. PMID:25123137

Darewicz, Ma?gorzata; Borawska, Justyna; Vegarud, Gerd E.; Minkiewicz, Piotr; Iwaniak, Anna

2014-01-01

138

Proactive and reactive inhibitory control in rats.  

PubMed

Inhibiting actions inappropriate for the behavioral context, or inhibitory control, is essential for survival and involves both reactively stopping the current prepared action and proactively adjusting behavioral tendencies to increase future performance. A powerful paradigm widely used in basic and clinical research to study inhibitory control is the stop signal task (SST). Recent years have seen a surging interest in translating the SST to rodents to study the neural mechanisms underlying inhibitory control. However, significant differences in task designs and behavioral strategies between rodent and primate studies have made it difficult to directly compare the two literatures. In this study, we developed a rodent-appropriate SST and characterized both reactive and proactive control in rats. For reactive inhibitory control, we found that, unlike in primates, incorrect stop trials in rodents result from two independent types of errors: an initial failure-to-stop error or, after successful stopping, a subsequent failure-to-wait error. Conflating failure-to-stop and failure-to-wait errors systematically overestimates the covert latency of reactive inhibition, the stop signal reaction time (SSRT). To correctly estimate SSRT, we developed and validated a new method that provides an unbiased SSRT estimate independent of the ability to wait. For proactive inhibitory control, we found that rodents adjust both their reaction time and the ability to stop following failure-to-wait errors and successful stop trials, but not after failure-to-stop errors. Together, these results establish a valid rodent model that utilizes proactive and reactive inhibitory control strategies similar to primates, and highlight the importance of dissociating initial stopping from subsequent waiting in studying mechanisms of inhibitory control using rodents. PMID:24847204

Mayse, Jeffrey D; Nelson, Geoffrey M; Park, Pul; Gallagher, Michela; Lin, Shih-Chieh

2014-01-01

139

Proactive and reactive inhibitory control in rats  

PubMed Central

Inhibiting actions inappropriate for the behavioral context, or inhibitory control, is essential for survival and involves both reactively stopping the current prepared action and proactively adjusting behavioral tendencies to increase future performance. A powerful paradigm widely used in basic and clinical research to study inhibitory control is the stop signal task (SST). Recent years have seen a surging interest in translating the SST to rodents to study the neural mechanisms underlying inhibitory control. However, significant differences in task designs and behavioral strategies between rodent and primate studies have made it difficult to directly compare the two literatures. In this study, we developed a rodent-appropriate SST and characterized both reactive and proactive control in rats. For reactive inhibitory control, we found that, unlike in primates, incorrect stop trials in rodents result from two independent types of errors: an initial failure-to-stop error or, after successful stopping, a subsequent failure-to-wait error. Conflating failure-to-stop and failure-to-wait errors systematically overestimates the covert latency of reactive inhibition, the stop signal reaction time (SSRT). To correctly estimate SSRT, we developed and validated a new method that provides an unbiased SSRT estimate independent of the ability to wait. For proactive inhibitory control, we found that rodents adjust both their reaction time and the ability to stop following failure-to-wait errors and successful stop trials, but not after failure-to-stop errors. Together, these results establish a valid rodent model that utilizes proactive and reactive inhibitory control strategies similar to primates, and highlight the importance of dissociating initial stopping from subsequent waiting in studying mechanisms of inhibitory control using rodents. PMID:24847204

Mayse, Jeffrey D.; Nelson, Geoffrey M.; Park, Pul; Gallagher, Michela; Lin, Shih-Chieh

2014-01-01

140

Venus ionopause during solar minimum  

NASA Astrophysics Data System (ADS)

Pioneer Venus ion composition measurements are used to study the Venus ionosphere during solar minimum. It is suggested that the topside electron density profile at Venus during solar minimum has two distinct regimes. One beween 140 and 180 km is dominated by O2(+) ions which are in photochemical equilibrium. The other regime is above 180 km and is dominated by O(+) ions which are disturbed by the solar wind induced plasma transport. For Pioneer Venus, Mariner 10, and Venera 9 and 10 data, it is found that Venus exhibits a photodynamical type of ionopause during solar minimum.

Mahajan, K. K.; Mayr, H. G.

1989-12-01

141

Venus ionopause during solar minimum  

NASA Technical Reports Server (NTRS)

Pioneer Venus ion composition measurements are used to study the Venus ionosphere during solar minimum. It is suggested that the topside electron density profile at Venus during solar minimum has two distinct regimes. One beween 140 and 180 km is dominated by O2(+) ions which are in photochemical equilibrium. The other regime is above 180 km and is dominated by O(+) ions which are disturbed by the solar wind induced plasma transport. For Pioneer Venus, Mariner 10, and Venera 9 and 10 data, it is found that Venus exhibits a photodynamical type of ionopause during solar minimum.

Mahajan, K. K.; Mayr, H. G.

1989-01-01

142

Stability and cytotoxicity of angiotensin-I-converting enzyme inhibitory peptides derived from bovine casein*  

PubMed Central

This study investigated the effect of heat treatment combined with acid and alkali on the angiotensin-I-converting enzyme (ACE) inhibitory activity of peptides derived from bovine casein. The free amino group content, color, and cytotoxicity of the peptides were measured under different conditions. When heated at 100 °C in the pH range from 9.0 to 12.0, ACE inhibitory activity was reduced and the appearance of the peptides was significantly darkened. After thermal treatment in the presence of acid and alkali, the free amino group content of ACE inhibitory peptides decreased markedly. High temperature and prolonged heating also resulted in the loss of ACE inhibitory activity, the loss of free amino groups, and the darker coloration of bovine casein-derived peptides. However, ACE inhibitory peptides, within a concentration range of from 0.01 to 0.2 mg/ml, showed no cytotoxicity to Caco-2 and ECV-304 cell lines after heat treatment. This indicated that high temperature and alkaline heat treatment impaired the stability of bovine casein-derived ACE inhibitory peptides. PMID:24510707

Wu, Wei; Yu, Pan-pan; Zhang, Feng-yang; Che, Hong-xia; Jiang, Zhan-mei

2014-01-01

143

Inhibitory effects of pomegranate extracts on recombinant human maltase-glucoamylase.  

PubMed

?-Glucosidase inhibitors are currently used in the treatment of type 2 diabetes. In this study, we investigated the inhibitory activities of aril and pericarp extracts from pomegranates obtained various regions against recombinant human maltase-glucoamylase (MGAM). The inhibitory activities of the aril extracts tended to be stronger than those of the pericarp extracts. The Iranian aril extract was the most effective inhibitor. We investigated the polyphenol content of the pomegranate extracts using the Folin-Ciocalteu method. Among the aril extracts, the Iranian aril extract showed the highest polyphenol content. We further evaluated inhibitory activity against ?-glucosidase from the rat small intestine. Pomegranate extract used in this study showed slightly different inhibitory activities according to ?-glucosidase origin. Iranian aril extract was the most effective inhibitor of ?-glucosidases, especially recombinant human MGAM. Bioassay-guided fractionation of the pomegranate arils led to identification of punicalagin and oenothein B as potent inhibitors of ?-glucosidase. Oenothein B showed inhibitory activity with a half-maximal inhibitory concentration (IC(50)) value of 174 ?M. Its potency was comparable to that of the ?-glucosidase inhibitor acarbose with an IC(50) value of 170 ?M. Dixon plot kinetic analysis of oenothein B showed a noncompetitive inhibition with a K(i) value of 102 ?M. These results suggest that pomegranate arils would be useful for suppressing postprandial hyperglycemia. PMID:25154971

Kawakami, Kayoko; Li, Peng; Uraji, Misugi; Hatanaka, Tadashi; Ito, Hideyuki

2014-09-01

144

Microbial adhesion of Cryptosporidium parvum: Identification of a colostrum-derived inhibitory lipid  

PubMed Central

We previously described an unidentified lipid purified from calf small intestine that inhibits the in vitro adhesion of Cryptosporidium parvum sporozoites to host cells [Johnson JK, Schmidt J, Gelberg HB, Kuhlenschmidt MS. Microbial adhesion of Cryptosporidium parvum sporozoites: purification of an inhibitory lipid from bovine mucosa. J Parasitol 2004;90:980–90]. Intestinal mucosa from some calves, however, failed to yield this bioactive lipid. Accordingly, we examined other potential sources, especially dietary sources, of the inhibitory lipid and discovered it was principally derived from bovine colostrum. Interestingly, fresh colostrum yielded little or no inhibitory lipid, however, the lipid was found in relatively large quantities following incubation of colostrum with the aqueous fraction of calf intestinal contents. Using FAB-MS and NMR analysis, the sporozoite inhibitory lipid (SIL) was identified as oleic acid, a monounsaturated fatty acid likely released from colostrum triglycerides and phospholipids by digestion in the lumen of the calf small intestine. Oleic acid dose-dependently inhibited in vitro sporozoite–host cell adhesion with an inhibitory constant (IC50) of approximately 5 ?M. Comparison of oleic acid with other C-18 fatty acids revealed linolenic, but not stearic acid, also displayed potent inhibitory activity. Neither linolenic nor oleic acid, however, affect either sporozoite or host cell viability at concentrations that inhibit sporozoite adhesion. These results suggest certain colostrum-derived long-chain fatty acids may serve as natural inhibitors of the early steps in C. parvum sporozoite–host cell interactions. PMID:18675305

Schmidt, Joann; Kuhlenschmidt, Mark S.

2008-01-01

145

Cyclooxygenase inhibitory and antioxidant cyanidin glycosides in cherries and berries.  

PubMed

Anthocyanins from tart cherries, Prunus cerasus L. (Rosaceae) cv. Balaton and Montmorency; sweet cherries, Prunus avium L. (Rosaceae); bilberries, Vaccinum myrtillus L. (Ericaceae); blackberries, Rubus sp. (Rosaceae); blueberries var. Jersey, Vaccinium corymbosum L. (Ericaceae); cranberries var. Early Black, Vaccinium macrocarpon Ait. (Ericaceae); elderberries, Sambucus canadensis (Caprifoliaceae); raspberries, Rubus idaeus (Rosaceae); and strawberries var. Honeoye, Fragaria x ananassa Duch. (Rosaceae), were investigated for cyclooxygenase inhibitory and antioxidant activities. The presence and levels of cyanidin-3-glucosylrutinoside 1 and cyanidin-3-rutinoside 2 were determined in the fruits using HPLC. The antioxidant activity of anthocyanins from cherries was comparable to the commercial antioxidants, tert-butylhydroquinone, butylated hydroxytoluene and butylated hydroxyanisole, and superior to vitamin E, at a test concentration of 125 microg/ml. Anthocyanins from raspberries and sweet cherries demonstrated 45% and 47% cyclooxygenase-I and cyclooxygenase-II inhibitory activities, respectively, when assayed at 125 microg/ml. The cyclooxygenase inhibitory activities of anthocyanins from these fruits were comparable to those of ibuprofen and naproxen at 10 microM concentrations. Anthocyanins 1 and 2 are present in both cherries and raspberry. The yields of pure anthocyanins 1 and 2 in 100 g Balaton and Montmorency tart cherries, sweet cherries and raspberries were 21, 16.5; 11, 5; 4.95, 21; and 4.65, 13.5 mg, respectively. Fresh blackberries and strawberries contained only anthocyanin 2 in yields of 24 and 22.5 mg/100 g, respectively. Anthocyanins 1 and 2 were not found in bilberries, blueberries, cranberries or elderberries. PMID:11695879

Seeram, N P; Momin, R A; Nair, M G; Bourquin, L D

2001-09-01

146

Inhibitory Regulation of Dendritic Activity in vivo  

PubMed Central

The spatiotemporal control of neuronal excitability is fundamental to the inhibitory process. We now have a wealth of information about the active dendritic properties of cortical neurons including axonally generated sodium action potentials as well as local sodium spikelets generated in the dendrites, calcium plateau spikes, and NMDA spikes. All of these events have been shown to be highly modified by the spatiotemporal pattern of nearby inhibitory input which can drastically change the output firing mode of the neuron. This means that particular populations of interneurons embedded in the neocortical microcircuitry can more precisely control pyramidal cell output than has previously been thought. Furthermore, the output of any given neuron tends to feed back onto inhibitory circuits making the resultant network activity further dependent on inhibition. Network activity is therefore ultimately governed by the subcellular microcircuitry of the cortex and it is impossible to ignore the subcompartmentalization of inhibitory influence at the neuronal level in order to understand its effects at the network level. In this article, we summarize the inhibitory circuits that have been shown so far to act on specific dendritic compartments in vivo. PMID:22654734

Palmer, Lucy; Murayama, Masanori; Larkum, Matthew

2012-01-01

147

Minimum energy mobile wireless networks  

Microsoft Academic Search

We describe a distributed position-based network protocol optimized for minimum energy consumption in mobile wireless networks that support peer-to-peer communications. Given any number of randomly deployed nodes over an area, we show that a simple local optimization scheme executed at each node guarantees strong connectivity of the entire network and attains the global minimum energy solution for the stationary case.

Volkan Rodoplu; Teresa H. Meng

1998-01-01

148

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

PubMed Central

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. PMID:23484103

Wu, Jin-Chao; Cheng, Jie; Shi, Xiao-lai

2013-01-01

149

Pharmacokinetics and tissue concentrations of tylosin in selected avian species.  

PubMed

Tissue and plasma concentrations and the biological half-life of tylosin in avian species of a variety of body sizes and metabolic rates were studied. The species chosen were eastern bobwhite quail (Colinus virginianus virginianus), pigeons (Columba livia), greater sandhill cranes (Grus canadensis tabida), and emus (Dromaius novaehollandiae). In the 1st phase of this study, tylosin was administered IM to quail, pigeons, and emus at a dosage rate of 25 mg/kg of body weight and to cranes at a dosage rate of 15 mg/kg. The average peak plasma concentrations of tylosin in quail, pigeons, cranes, and emus were 4.31, 5.63, 3.62, and 3.26 microgram/ml, respectively. These peak concentrations occurred at 0.5 to 1.5 hours after administration. The biological half-life of tylosin averaged 1.2 hours in quail, pigeons, and cranes, and was 4.7 hours in emus. In the 2nd phase of this study, tylosin concentrations in the tissues of quail, pigeons, and cranes were markedly higher than were plasma concentrations at corresponding sampling times. Six hours after antibiotic administration, tissue concentrations of tylosin in all species remained within the minimum inhibitory concentration for most pathogenic organisms. Dosage regimens of 25 mg of tylosin/kg 4 times daily for quail and pigeons, 15 mg/kg 3 times daily for cranes, and 25 mg/kg 3 times daily for emus would be needed to establish and maintain therapeutic tissue concentrations. PMID:7149381

Locke, D; Bush, M; Carpenter, J W

1982-10-01

150

Pharmacokinetics and tissue concentrations of tylosin in selected avian species  

USGS Publications Warehouse

Tissue and plasma concentrations and the biological half-life of tylosin in avian species of a variety of body sizes and metabolic rates were studied. The species chosen were eastern bobwhite quail (Colinus virginianus virginianus), pigeons (Columba livia), greater sandhill cranes (Grus canadensis tabida), and emus (Dromaius novaehollandiae). In the 1st phase of this study, tylosin was administered IM to quail, pigeons, and emus at a dosage rate of 25 mg/kg of body weight and to cranes at a dosage rate of 15 mg/kg. The average peak plasma concentrations of tylosin in quail, pigeons, cranes, and emus were 4.31, 5.63, 3.62, and 3.26 microgram/ml, respectively. These peak concentrations occurred at 0.5 to 1.5 hours after administration. The biological half-life of tylosin averaged 1.2 hours in quail, pigeons, and cranes, and was 4.7 hours in emus. In the 2nd phase of this study, tylosin concentrations in the tissues of quail, pigeons, and cranes were markedly higher than were plasma concentrations at corresponding sampling times. Six hours after antibiotic administration, tissue concentrations of tylosin in all species remained within the minimum inhibitory concentration for most pathogenic organisms. Dosage regimens of 25 mg of tylosin/kg 4 times daily for quail and pigeons, 15 mg/kg 3 times daily for cranes, and 25 mg/kg 3 times daily for emus would be needed to establish and maintain therapeutic tissue concentrations.

Locke, D.; Bush, M.; Carpenter, J.W.

1982-01-01

151

Cephalosporin and Aminoglycoside Concentrations in Peritoneal Capsular Fluid in Rabbits  

PubMed Central

To study the penetration of antibiotics into peritoneal tissue fluid, a subcutaneous tissue capsule model was modified by implanting multiple, perforated spherical capsules in the peritoneal cavity of rabbits. Capsules became vascularized, encased in connective tissue, and filled with fluid having a mean protein concentration of 3.6 g/100 ml. Capsular fluid was obtained by percutaneous needle aspiration and assayed for antibiotic by the disk plate bioassay technique. Cephalosporins were administered intramuscularly at a dose of 30 mg/kg. Mean peak concentrations of cephaloridine and cefazolin were significantly higher than cephalothin and cephapirin in capsular fluids, but the percent penetration (ratio of capsular mean peak to serum mean peak) ranged from 8.7 to 16.9% and was not significantly different among the cephalosporins. At 24 h the capsular concentration of cefazolin was significantly greater than for the other cephalosporins (P < 0.001). Lower rabbit serum protein binding observed at high in vivo concentrations may have enabled cefazolin to penetrate capsular fluid, but in vitro protein binding studies did not confirm a decrease in serum protein binding at high concentrations within the clinical range. Kanamycin and amikacin showed comparable capsular fluid peak concentrations as did gentamicin and tobramycin. The percent penetration ranged from 15.2 to 34.5% for the aminoglycosides. The only statistical difference was that amikacin penetration was significantly higher than that for tobramycin. Mean capsular concentrations of amikacin, cefazolin, and cephaloridine compared most favorably with the minimum inhibitory concentration of gram-negative bacilli at the dosages used in this study. Images PMID:1008548

Gerding, Dale N.; Hall, Wendell H.; Schierl, Elizabeth A.; Manion, Robert E.

1976-01-01

152

Inhibitory effects of phytoncide solution on melanin biosynthesis.  

PubMed

To determine the component-activity relationships of phytoncide solutions on inhibitory activity in melanin biosynthesis, four types of phytoncide solution (A-type, AB-type, D-type, and G-type) were evaluated for inhibition of mushroom tyrosinase activity and melanin synthesis on murine B-16 melanoma cells and a human reconstituted skin model. The A-type, AB-type, D-type, and G-type of phytoncide solution treatment resulted in significant inhibition of tyrosinase activity. The amount of melanin was increased by treatment with phytoncide solutions in a concentration-dependent manner on murine B-16 melanoma cells without affecting cell growth. Furthermore, phytoncide solutions also suppressed melanin synthesis in a concentration-dependent manner on a human reconstituted skin model. These effects of A-type solution were superior to those of other solutions. PMID:20460709

Fujimori, Hiroaki; Hisama, Masayoshi; Shibayama, Hiroharu; Kawase, Atsushi; Iwaki, Masahiro

2010-01-01

153

Neurological Deterioration in Acute Lacunar Infarctions The Role of Excitatory and Inhibitory Neurotransmitters  

Microsoft Academic Search

Background and Purpose—The mechanisms involved in the neurological deterioration of acute lacunar strokes are unknown. Although accumulating evidence suggests that glutamate release plays a role in the progression of territorial infarctions, it remains to be established whether excitotoxicity also participates in lacunar stroke progression. We investigated whether excitatory and inhibitory amino acid concentrations in blood predict subsequent progressive motor deficits

Joaquín Serena; Rogelio Leira; José Castillo; José Manuel Pumar; Mar Castellanos; Antoni Dávalos

154

Immunotherapies: The Blockade of Inhibitory Signals  

PubMed Central

T lymphocytes require signaling by the T cell receptor and by nonclonotypic cosignaling receptors. The costimulatory and inhibitory signals profoundly influence the course of immune responses by amplifying or reducing the transcriptional effects of T cell receptor triggering. The inhibitory receptors such as CTLA-4, PD-1, and BTLA have recently drawn much attention as potential targets for immunotherapies. This review focuses on the progress that has been made with the mentioned receptors in the field of immunotherapies for autoimmune diseases, malignancies, infectious diseases, and transplantation. PMID:23197939

Wu, Yan-Ling; Liang, Jing; Zhang, Wen; Tanaka, Yoshimasa; Sugiyama, Hiroshi

2012-01-01

155

Activity-dependent adaptations in inhibitory axons  

PubMed Central

Synaptic connections in our brains change continuously and throughout our lifetime. Despite ongoing synaptic changes, a healthy balance between excitation and inhibition is maintained by various forms of homeostatic and activity-dependent adaptations, ensuring stable functioning of neuronal networks. In this review we summarize experimental evidence for activity-dependent changes occurring in inhibitory axons, in cultures as well as in vivo. Axons form many presynaptic terminals, which are dynamic structures sharing presynaptic material along the axonal shaft. We discuss how internal (e.g., vesicle sharing) and external factors (e.g., binding of cell adhesion molecules or secreted factors) may affect the formation and plasticity of inhibitory synapses. PMID:24312009

Frias, Cátia P.; Wierenga, Corette J.

2013-01-01

156

The inhibitory effect of Mesembryanthemum edule (L.) bolus essential oil on some pathogenic fungal isolates  

PubMed Central

Background Mesembryanthemum edule is a medicinal plant which has been indicated by Xhosa traditional healers in the treatment HIV associated diseases such as tuberculosis, dysentery, diabetic mellitus, laryngitis, mouth infections, ringworm eczema and vaginal infections. The investigation of the essential oil of this plant could help to verify the rationale behind the use of the plant as a cure for these illnesses. Methods The essential oil from M. edule was analysed by GC/MS. Concentration ranging from 0.005 - 5 mg/ml of the hydro-distilled essential oil was tested against some fungal strains, using micro-dilution method. The plant minimum inhibitory activity on the fungal strains was determined. Result GC/MS analysis of the essential oil resulted in the identification of 28 compounds representing 99.99% of the total essential oil. A total amount of 10.6 and 36.61% constituents were obtained as monoterpenes and oxygenated monoterpenes. The amount of sesquiterpene hydrocarbons (3.58%) was low compared to the oxygenated sesquiterpenes with pick area of 9.28%. Total oil content of diterpenes and oxygenated diterpenes detected from the essential oil were 1.43% and 19.24%. The fatty acids and their methyl esters content present in the essential oil extract were found to be 19.25%. Antifungal activity of the essential oil extract tested against the pathogenic fungal, inhibited C. albican, C. krusei, C. rugosa, C. glabrata and C. neoformans with MICs range of 0.02-0.31 mg/ml. the activity of the essential oil was found competing with nystatin and amphotericin B used as control. Conclusion Having accounted the profile chemical constituent found in M. edule oil and its important antifungal properties, we consider that its essential oil might be useful in pharmaceutical and food industry as natural antibiotic and food preservative. PMID:24885234

2014-01-01

157

Potent ?-amylase inhibitory activity of Indian Ayurvedic medicinal plants  

PubMed Central

Background Indian medicinal plants used in the Ayurvedic traditional system to treat diabetes are a valuable source of novel anti-diabetic agents. Pancreatic ?-amylase inhibitors offer an effective strategy to lower the levels of post-prandial hyperglycemia via control of starch breakdown. In this study, seventeen Indian medicinal plants with known hypoglycemic properties were subjected to sequential solvent extraction and tested for ?-amylase inhibition, in order to assess and evaluate their inhibitory potential on PPA (porcine pancreatic ?-amylase). Preliminary phytochemical analysis of the lead extracts was performed in order to determine the probable constituents. Methods Analysis of the 126 extracts, obtained from 17 plants (Aloe vera (L.) Burm.f., Adansonia digitata L., Allium sativum L., Casia fistula L., Catharanthus roseus (L.) G. Don., Cinnamomum verum Persl., Coccinia grandis (L.) Voigt., Linum usitatisumum L., Mangifera indica L., Morus alba L., Nerium oleander L., Ocimum tenuiflorum L., Piper nigrum L., Terminalia chebula Retz., Tinospora cordifolia (Willd.) Miers., Trigonella foenum-graceum L., Zingiber officinale Rosc.) for PPA inhibition was initially performed qualitatively by starch-iodine colour assay. The lead extracts were further quantified with respect to PPA inhibition using the chromogenic DNSA (3, 5-dinitrosalicylic acid) method. Phytochemical constituents of the extracts exhibiting? 50% inhibition were analysed qualitatively as well as by GC-MS (Gas chromatography-Mass spectrometry). Results Of the 126 extracts obtained from 17 plants, 17 extracts exhibited PPA inhibitory potential to varying degrees (10%-60.5%) while 4 extracts showed low inhibition (< 10%). However, strong porcine pancreatic amylase inhibitory activity (> 50%) was obtained with 3 isopropanol extracts. All these 3 extracts exhibited concentration dependent inhibition with IC50 values, viz., seeds of Linum usitatisumum (540 ?gml-1), leaves of Morus alba (1440 ?gml-1) and Ocimum tenuiflorum (8.9 ?gml-1). Acarbose as the standard inhibitor exhibited an IC50 (half maximal inhibitory concentration)value of 10.2 ?gml-1. Phytochemical analysis revealed the presence of alkaloids, tannins, cardiac glycosides, flavonoids, saponins and steroids with the major phytoconstituents being identified by GC-MS. Conclusions This study endorses the use of these plants for further studies to determine their potential for type 2 diabetes management. Results suggests that extracts of Linum usitatisumum, Morus alba and Ocimum tenuiflorum act effectively as PPA inhibitors leading to a reduction in starch hydrolysis and hence eventually to lowered glucose levels. PMID:21251279

2011-01-01

158

Comparison of the inhibitory and lethal effects of synthetic versions of plant metabolites (anethole, carvacrol, eugenol, and thymol) on a food spoilage yeast (Debaromyces hansenii)  

Microsoft Academic Search

The inhibitory and lethal effects of synthetic versions of compounds found in common herbs and spices were compared on a food spoilage yeast Debaromyces hansenii. Separate treatments of trans?anethole, carvacrol, eugenol, and thymol were investigated in potato dextrose broth (PDB) suspension cultures. Inhibitory activity was studied for all compounds at concentrations of 25, 50, 75, and 100 ppm over a

O. F. Curtis; K. Shetty; G. Cassagnol; M. Peleg

1996-01-01

159

Lactoferrin and lysozyme in milk during acute mastitis and their inhibitory effect in Delvotest P.  

PubMed

Microbiological methods for detection of antibiotic residues in milk give no explanations regarding the identity of the inhibitory substance(s). Natural antibacterial substances, present at higher concentrations in mastitic milk and in colostrum, occasionally cause false positive results in antibiotic assays. In an earlier investigation, lysozyme and lactoferrin were shown to inhibit the growth of Bacillus stearothermophilus var. calidolactis spores, used as test organism in Delvotest P. To study the effect of high lysozyme and lactoferrin concentrations in milk on the Delvotest P, cows were subjected to acute experimental mastitis by infusion of Salmonella typhimurium SH 4809 endotoxin. Milk samples were collected up to 11 h postinfusion. Concentrations of lactoferrin and lysozyme, somatic cell count, and effect on Delvotest P were determined. A positive reaction in the Delvotest correlated well with an increase in lactoferrin and lysozyme concentrations. The nature of the inhibitory effect is briefly discussed. PMID:2628440

Carlsson, A; Björck, L; Persson, K

1989-12-01

160

A Novel Inhibitory Receptor of Platelets  

Cancer.gov

The National Cancer Institute's Molecular Targets Laboratory is seeking statements of capability or interest from parties interested in collaborative research on a novel, inhibitory platelet surface protein known as TREM like Transcript (TLT-1). The collaborative research would be pre-clinical development of a potential therapeutic target for thrombosis and other platelet-associated disorders, as well as immune disorders.

161

Inhibitory effect of homologous solubilized zona pellucida  

E-print Network

(275-165) kd, 100 (135-96) kd and 75 (96-51 ) kd. Preincubation of sperm with heat-solubilized zonaeInhibitory effect of homologous solubilized zona pellucida on rabbit in vitro fertilization Martine zonae pellucidae were isolated using a modified technique of Dunbar et al (1980). Zonae pellucidae were

Paris-Sud XI, Université de

162

Paired inhibitory and activating receptor signals.  

PubMed

The immunological literature has become inundated with reports regarding paired inhibitory receptors. Paired inhibitory receptor systems are highly conserved families that contain receptors involved in either cellular inhibition or activation. In most cases the paired putative biochemical antagonists are co-expressed on a given cell and thought to bind similar, if not identical, ligands making their biological role difficult to understand. Examples of these systems include immunoglobulin (Ig)-like receptors (Killer Ig Receptors, Immunoglobulin-like Transcripts/Leukocyte Ig-like Receptors/Monocyte Macrophage Ig Receptors, and Paired Ig-like Receptors), and type II lectin-like receptor systems (NKG2 and Ly49). General characteristics of these inhibitory receptors include a cytoplasmic immunoreceptor tyrosine-based inhibitory motif (ITIM). The ITIM is phosphorylated upon engagement and recruits protein tyrosine phosphatases that dephosphorylate cellular substrates that would otherwise mediate activation. In contrast, the activating receptors of these pairs use charged residues within their transmembrane domains to associate with various signal transduction chains including the gamma chain of the receptor for the Fc portion of IgE, DAP12 or DAP10. Once phosphorylated, these chains direct the signal transduction cascade resulting in cellular activation. Here we review the signaling of several paired systems and present the current models for their signal transduction cascades. PMID:11258418

Taylor, L S; Paul, S P; McVicar, D W

2000-01-01

163

Inhibitory Effects of Oxyradicals on Surfactant Function: Utilizing in Vitro Fenton Reaction  

Microsoft Academic Search

.   The inhibitory effects of reactive oxygen species (ROS) on the surface tension-lowering abilities of three surfactants were\\u000a compared: natural lung surfactant (NLS), KL4 surfactant containing synthetic peptide resembling the hydrophobic\\/hydrophilic domains of SP-B in an aqueous dispersion of\\u000a phospholipids, and Survanta® (SUR) containing SP-B and SP-C. The inhibitory concentrations of Fenton reactants (i.e. 0.65\\u000a mM FeCl2, 0.65 mM EDTA,

J. D. Amirkhanian; T. A. Merritt

1998-01-01

164

Inhibitory effects of organic solvent extracts from Korean local plants on the complement classical pathway.  

PubMed

The study evaluated the anticomplement effects from organic solvent extracts of five Compositae plants (Ligularia fischeri (Ledeb.) Turez, Ligularia taquetii (H.Lev. & Vaniot) Nakai, Ainsliaea acerifolia Sch.Bip, Aster scaber Thunb, Aster koraiensis Nakai, Synurus deltoides Aiton) from South Korea on the classical pathway complement system. We have evaluated organic solvent extracts from five Compositae with regard to its anticomplement activity. Chloroform extracts from L. taquetii showed inhibitory activity against complement system with 50% inhibitory concentrations (IC??) values of 73.2??g/mL. This is the first report of anticomplement activity from L. taquetii. PMID:21506692

Moon, Hyung-In; Lee, Jai-Heon; Lee, Young-Choon

2012-02-01

165

ACSB: A minimum performance assessment  

NASA Technical Reports Server (NTRS)

Amplitude companded sideband (ACSB) is a new modulation technique which uses a much smaller channel width than does conventional frequency modulation (FM). Among the requirements of a mobile communications system is adequate speech intelligibility. This paper explores this aspect of minimum required performance. First, the basic principles of ACSB are described, with emphasis on those features that affect speech quality. Second, the appropriate performance measures for ACSB are reviewed. Third, a subjective voice quality scoring method is used to determine the values of the performance measures that equate to the minimum level of intelligibility. It is assumed that the intelligibility of an FM system operating at 12 dB SINAD represents that minimum. It was determined that ACSB operating at 12 dB SINAD with an audio-to-pilot ratio of 10 dB provides approximately the same intelligibility as FM operating at 12 dB SINAD.

Jones, Lloyd Thomas; Kissick, William A.

1988-01-01

166

Dynamic Capacitated Minimum Spanning Trees  

E-print Network

Given a set of terminals, each associated with a positive number denoting the traffic to be routed to a central terminal (root), the Capacitated Minimum Spanning Tree (CMST) problem asks for a minimum spanning tree, spanning all terminals, such that the amount of traffic routed from a subtree, linked to the root by an edge, does not exceed the given capacity constraint k. The CMST problem is NP-complete and has been extensively studied for the past 40 years. Current best heuristics, in terms of cost and computation time (O(n log n)), are due to Esau and Williams [1], and Jothi and Raghavachari [2].

Raja Jothi; Balaji Raghavachari

2004-01-01

167

Predicting the DPP-IV Inhibitory Activity pIC50 Based on Their Physicochemical Properties  

PubMed Central

The second development program developed in this work was introduced to obtain physicochemical properties of DPP-IV inhibitors. Based on the computation of molecular descriptors, a two-stage feature selection method called mRMR-BFS (minimum redundancy maximum relevance-backward feature selection) was adopted. Then, the support vector regression (SVR) was used in the establishment of the model to map DPP-IV inhibitors to their corresponding inhibitory activity possible. The squared correlation coefficient for the training set of LOOCV and the test set are 0.815 and 0.884, respectively. An online server for predicting inhibitory activity pIC50 of the DPP-IV inhibitors as described in this paper has been given in the introduction. PMID:23865065

Gu, Tianhong; Yang, Xiaoyan; Li, Minjie; Su, Qiang; Lu, Wencong; Zhang, Yuhui

2013-01-01

168

In vitro ? -amylase and ?-glucosidase inhibitory potential of Trigonella foenum-graecum leaves extract.  

PubMed

Trigonella foenum-graecum is one of the widely used herbs in food and medicine. The seeds of the plants are investigated for antidiabetic potential; however, no efforts have been done to explore the potential of leaves to modify carbohydrate metabolizing enzymes viz. ?-amylase and ?-glucosidase. The present work was designed to investigate the inhibitory potential of ethyl acetate and water extract of T. foenum-graecum on enzymes ?-amylase and ?-glucosidase. Different concentrations of extracts were used to study inhibition of enzymatic activity of ?-amylase and ?-glucosidase. A dose dependent inhibitory effect on enzymes was observed. The current study, for the first time, revealed ?-amylase and ?-glucosidase inhibitory potential of T. foenum-graecum and the study could be helpful to isolate and characterize compounds responsible for it. PMID:24049415

Ganeshpurkar, Aditya; Diwedi, Varsha; Bhardwaj, Yash

2013-01-01

169

Inhibitory effect of nitrite on coagulation processes demonstrated by thrombelastography.  

PubMed

Nitric oxide (NO) can be generated by two-step reduction pathway in which nitrate is converted first into nitrite and then into NO via several mechanisms, as well as from arginine by endogenous nitric oxide synthase (NOS). We have recently shown that nitrite ions in the presence of erythrocytes inhibit platelet aggregation and activation, as measured by aggregometry and flow cytometric analysis of P-selectin, through its reduction to NO under partially deoxygenated conditions. In the current study, we investigated how nitrite may affect overall clotting processes via modulating platelet function using thrombelastography (TEG). We measured three major TEG parameters, reaction time (R, time to initial fibrin formation), ? angle (velocity of clot growth) and maximum amplitude (MA, maximum clot strength) using blood from healthy volunteers. An NO donor (DEANONOate) showed inhibitory effects on all TEG parameters in platelet rich plasma (PRP) and whole blood, resulting in delayed R, decreased angle, and reduced MA in a dose dependent manner. Nitrite ions also exhibited inhibitory effects in whole blood at 20% hematocrit, and this was greatly enhanced under hypoxic conditions, being demonstrable at 0.1 ?M concentration. Neither compound changed any TEG parameters in plasma. Our results suggest that nitrite affects overall blood clotting and that TEG may be used to follow this process. Further the physiological effects of factors which determine NO bioavailability, such as endogenous levels of blood and tissue nitrite, may be useful as biomarkers for predicting hemostatic potential. PMID:24858214

Park, J W; Piknova, B; Nghiem, K; Lozier, J N; Schechter, A N

2014-08-31

170

Inhibitory Effects of Methylcellulose on Cellulose Degradation by Ruminococcus flavefaciens  

PubMed Central

Highly methylated, long-chain celluloses strongly inhibited cellulose degradation by several species of cellulolytic bacteria of ruminal origin. Specifically, the inhibitory effects of methylcellulose on the growth of Ruminococcus flavefaciens FD1 were concentration dependent, with complete inhibition at 0.1% (wt/vol). However, methylcellulose did not inhibit growth on cellobiose or cellulooligosaccharides. Mixtures of methylated cellulooligosaccharides having an average degree of polymerization of 6.7 to 9.5 inhibited cellulose degradation, but those with an average degree of polymerization of 1.0 to 4.5 did not. Similar inhibitory effects by methylcellulose and, to a lesser extent, by methyl cellulooligosaccharides were observed on cellulase activity, as measured by hydrolysis of p-nitrophenyl-?-d-cellobioside. R. flavefaciens cultures hydrolyzed cellulooligosaccharides to cellobiose and cellotriose as final end products. Cellopentaose and cellohexaose were cleaved to these end products, but cellotetraose was also formed from cellohexaose. Methylcellulose did not inhibit hydrolysis of cellulooligosaccharides. These data are consistent with the presence of separate cellulase (?-1,4-glucanase) and cellulodextrinase activities in R. flavefaciens. PMID:16347610

Rasmussen, M. A.; Hespell, R. B.; White, B. A.; Bothast, R. J.

1988-01-01

171

Inventory Management for Minimum Cost  

Microsoft Academic Search

One of the most popular types of inveatoiy management is the (Q, r) system, in which a quantity Q of an item is reordered whenever the inventory position reaches the reorder point r. A number of packaged computer programs are available for this system. However, these programs seldom give the minimum-cost values of Q and r, since they usually employ

David P. Herron

1967-01-01

172

Relationship between tyrosinase inhibitory action and oxidation-reduction potential of cosmetic whitening ingredients and phenol derivatives.  

PubMed

The oxidation-reduction potentials of cosmetic raw materials, showing tyrosinase inhibitory action, and phenolic compounds structurally similar to L-tyrosine were determined by cyclic voltammetry. The voltammograms obtained could be classified into 4 patterns (patterns 1-4). Pattern 1, characterized by oxidation and reduction peaks as a pair, was observed with catechol, hydroquinone or phenol, and pattern 2 exhibiting another oxidation peak in addition to oxidation and reduction peaks as a pair was found with arbutin, kojic acid, resorcinol, methyl p-hydroxybenzoate and L-tyrosine as the substrate of tyrosinase. Pattern 3 with an independent oxidation peak only was expressed by L-ascorbic acid, and pattern 4 with a reduction peak only at high potentials, by hinokitiol. The tyrosinase inhibitory activity of these compounds was also evaluated using the 50% inhibitory concentration (IC50) and the inhibition constant (Ki) as parameters. Hinokitiol, classified as pattern 4, showed the highest inhibitory activity (lowest IC50 and Ki). Hydroquinone showing the second highest activity belonged to pattern 1, which also included compounds showing no inhibition of tyrosinase activity. The inhibitory activity of compounds exhibiting pattern 2 was relatively low with Ki values being in the order of 10(-4) M. Although there was no consistent relationship between oxidation-reduction potentials and tyrosinase inhibitory action, the voltammetry data can be used as an additional index to establish the relationship between the structure and the tyrosine inhibitory activity. PMID:10489870

Sakuma, K; Ogawa, M; Sugibayashi, K; Yamada, K; Yamamoto, K

1999-08-01

173

Predictors of Longitudinal Growth in Inhibitory Control in Early Childhood  

ERIC Educational Resources Information Center

In the current study, we examined latent growth in 731 young children's inhibitory control from the ages of two to four years, and whether demographic characteristics or parenting behaviors were related to initial levels and growth in inhibitory control. As part of an ongoing longitudinal evaluation of the family check-up, children's inhibitory

Moilanen, Kristin L.; Shaw, Daniel S.; Dishion, Thomas J.; Gardner, Frances; Wilson, Melvin

2010-01-01

174

Glutamate is an inhibitory neurotransmitter in the Drosophila olfactory system  

E-print Network

Glutamate is an inhibitory neurotransmitter in the Drosophila olfactory system Wendy W. Liu acts as an inhibitory neurotransmitter in the antennal lobe, broadly similar to the role of GABA GABA and glycine serve as the major inhibitory neurotransmitters. Like the vertebrate CNS

Wilson, Rachel

175

Pharmacokinetic/pharmacodynamic modeling for concentration-dependent bactericidal activity of a bicyclolide, modithromycin.  

PubMed

The aim of this study was to develop a pharmacokinetic (PK)/pharmacodynamic (PD) model of a bicyclolide, modithromycin, to explain its concentration-dependent bactericidal activity based on the drug-bacterium interaction model that we developed. We have already reported the applicability of model to the time-dependent activity of ?-lactams, and we further applied the model to the concentration-dependent activity in this study. In vitro time-kill data of modithromycin, telithromycin, and clarithromycin against Staphylococcus aureus, Haemophilus influenzae, and Streptococcus pneumoniae were used for the modeling. An effect compartment model was incorporated into our original model to explain the time lag between PK and PD profiles. Also, a turnover model for reversible reduction of efficacy was incorporated to explain the regrowth. The developed model well described the time-kill profiles for each drug-bacterium combination. The estimated parameter related to efficacy strongly correlated with minimum inhibitory concentration (MIC), and the simulated bacterial counts at 24 h strongly correlated with both the ratio of the area under the concentration-time curve to MIC (AUC/MIC) and the ratio of the maximum concentration to MIC (Cmax /MIC). These results suggested that the proposed model can be applied to both concentration-dependent and time-dependent bactericidal kinetics, and would be useful for predicting the bactericidal activity of modithromycin. PMID:24523230

Katsube, Takayuki; Wajima, Toshihiro; Yamano, Yoshinori; Yano, Yoshitaka

2014-04-01

176

Prolonged deficits after focal inhibitory seizures  

Microsoft Academic Search

Introduction: Seizures are most commonly associated with positive phenomena such as tonic, clonic or myoclonic movements, automatisms,\\u000a paresthesias and hallucinations. Negative phenomena, however, are not an uncommon manifestation of seizure activity. Examples\\u000a of negative seizure phenomena include speech arrest, aphasia, amaurosis, amnesia, numbness, deafness, neglect and atonic seizures.\\u000a Less commonly described in the literature are focal inhibitory motor seizures.\\u000a \\u000a \\u000a Methods

Miguel Bussičre; David Pelz; Robert H Reid; G. Bryan Young

2005-01-01

177

Human immunodeficiency virus type 1 inhibitory activity of Mentha longifolia.  

PubMed

Extracts from a new chemotype of Mentha longifolia, a mint species that grows spontaneously and widely in the Moroccan mountains, were tested against human immunodeficiency virus type 1 (HIV-1). We observed that non-toxic concentrations (10 microg/mL) of extracts from this plant, in particular methanol (Ext-1) and ethyl acetate (Ext-3) extracts, significantly inhibit (p < 0.01) HIV-1BaL infection by about 40% and 55%, respectively. In addition, only Ext-3 shows significant (p < 0.008) inhibitory activity (50% inhibition) against HIV-1 reverse transcriptase. It is noteworthy that chemical analysis of these extracts suggests that flavonoids, mainly flavones of M. longifolia, may be the major inhibitors of HIV infection. In conclusion, these in vitro data suggest that components of M. longifolia may represent potential anti-HIV agents; the identification of such components is in progress. PMID:15058498

Amzazi, Saaďd; Ghoulami, Saaďd; Bakri, Youssef; Il Idrissi, Abdelkader; Fkih-Tétouani, Souad; Benjouad, Abdelaziz

2003-01-01

178

Urease inhibitory activities of ?-boswellic acid derivatives  

PubMed Central

Background and the purpose of the study Boswellia carterii have been used in traditional medicine for many years for management different gastrointestinal disorders. In this study, we wish to report urease inhibitory activity of four isolated compound of boswellic acid derivative. Methods 4 pentacyclic triterpenoid acids were isolated from Boswellia carterii and identified by NMR and Mass spectroscopic analysis (compounds 1, 3-O-acetyl-9,11-dehydro-?-boswellic acid; 2, 3-O-acetyl-11-hydroxy-?-boswellic acid; 3. 3-O- acetyl-11-keto-?-boswellic acid and 4, 11-keto-?-boswellic acid. Their inhibitory activity on Jack bean urease were evaluated. Docking and pharmacophore analysis using AutoDock 4.2 and Ligandscout 3.03 programs were also performed to explain possible mechanism of interaction between isolated compounds and urease enzyme. Results It was found that compound 1 has the strongest inhibitory activity against Jack bean urease (IC50?=?6.27?±?0.03 ?M), compared with thiourea as a standard inhibitor (IC50?=?21.1?±?0.3 ?M). Conclusion The inhibition potency is probably due to the formation of appropriate hydrogen bonds and hydrophobic interactions between the investigated compounds and urease enzyme active site and confirms its traditional usage. PMID:23351363

2013-01-01

179

Acetylcholinesterase and butyrylcholinesterase inhibitory activity of some Turkish medicinal plants.  

PubMed

The chloroform:medianol (1:1) extracts of a number of the plant species belonging to eight families, namely Corydalis solida (L.) Swartz subsp. solida and Glaucium corniculatum (L.) J. H. Rudolph (Papaveraceae), Rhododendron ponticum L. subsp. ponticum and Rhododendron luteum Sweet. (Ericaceae), Buxus sempervirens L. (Buxaceae), Vicia faba L. (Fabaceae), Robinia pseudoacacia L. (Caeselpiniaceae), Tribulus terrestris L. and Zygophyllum fabago L. (Zygophyllaceae), Lycopodium clavatum L. (Lycopodiaceae), Fumaria vaillantii Lois., Fumaria capreolata L., Fumaria kralikii Jordan, Fumaria asepala Boiss., Fumaria densiflora DC., Fumaria flabellata L., Fumaria petteri Reichb. subsp. thuretii (Boiss.) Pugsley, Fumaria macrocarpa Boiss. ex Hausskn., Fumaria cilicica Hauskkn., Fumaria parviflora Lam. and Fumaria judaica Boiss. (Fumariaceae) were screened for their anticholinesterase activity on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes by in vitro Ellman method at 10 microg/ml and 1 mg/ml concentrations. The extracts did not show any noticeable inhibitory activity against both of the enzymes at 10 microg/ml. The extracts of Rhododendron ponticum subsp. ponticum, Rhododendron luteum, Corydalis solida subsp. solida, Glaucium corniculatum, and Buxus sempervirens showed remarkable inhibitory activity above 50% inhibition rate on AChE at 1 mg/ml. Among them, Rhododendron ponticum subsp. ponticum, Corydalis solida subsp. solida and Buxus sempervirens were the most active extracts against BChE having 95.46 +/- 1.03%, 93.08 +/- 0.97%, and 93.45 +/- 0.88% inhibition rates, respectively. Among the extracts screened, all of the Fumaria extracts displayed highly potent inhibition against both of the enzymes at 1 mg/ml concentration compared to the standard. PMID:15036468

Orhan, I; Sener, B; Choudhary, M I; Khalid, A

2004-03-01

180

GMTI radar minimum detectable velocity.  

SciTech Connect

Minimum detectable velocity (MDV) is a fundamental consideration for the design, implementation, and exploitation of ground moving-target indication (GMTI) radar imaging modes. All single-phase-center air-to-ground radars are characterized by an MDV, or a minimum radial velocity below which motion of a discrete nonstationary target is indistinguishable from the relative motion between the platform and the ground. Targets with radial velocities less than MDV are typically overwhelmed by endoclutter ground returns, and are thus not generally detectable. Targets with radial velocities greater than MDV typically produce distinct returns falling outside of the endoclutter ground returns, and are thus generally discernible using straightforward detection algorithms. This document provides a straightforward derivation of MDV for an air-to-ground single-phase-center GMTI radar operating in an arbitrary geometry.

Richards, John Alfred

2011-04-01

181

Comparison of aqueous humour concentration after single high dose versus multiple administration of topical moxifloxacin in rabbits.  

PubMed

For the prevention of postoperative ocular infections prophylactic topical antibiotics are routinely used. Studies evaluating comparative difference between single dose versus multiple dose administration on aqueous humour concentration of moxifloxacin are lacking. This study compared the aqueous humour concentration of moxifloxacin following its topical administration in rabbit eyes with two dose regimens. Twelve albino rabbits were divided into two groups. In group-1, two drops were administered thrice (total six drops) at 2 min intervals, in both the eyes; in group-2, two drops of moxifloxacin were administered three times a day for three days and also two h before aqueous humour collection i.e. on fourth day. Mean aqueous humour concentrations were calculated and compared using Student's 't' test and P<0.05 was considered significant. Moxifloxacin concentration in aqueous humour in group-1 was 23.79 ?g/ml and in group-2 was 42.08 ?g/ml. Both dosing regimens produced substantially higher aqueous concentrations than the known minimum inhibitory concentration for most bacteria. Moxifloxacin concentration in aqueous humour with multiple instillations is significantly higher than single instillation (P<0.05), which is adequate to cover ciprofloxacin-resistant gram-negative bacteria. Repeated topical moxifloxacin administration achieved significantly higher aqueous humour concentrations than single administration. PMID:25425764

Chopra, Monika; Rehan, H S; Gupta, Rachna; Ahmad, F J; Tariq, M D; Gupta, L K

2014-09-01

182

Safe Minimum Internal Temperature Chart  

MedlinePLUS

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183

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

PubMed Central

Pancreatic ?-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 ?-amylase inhibition, in order to assess and evaluate their inhibitory potential on pancreatic ?-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??gmL?1), Syzygium cumini seeds (42.1 and 4.1??gmL?1), isopropanol extracts of Cinnamomum verum leaves (1.0??gmL?1) and Curcuma longa rhizome (0.16??gmL?1). The other 4 extracts exhibited concentration independent inhibition, namely, methanol extract of Bixa orellana leaves (49??gmL?1), isopropanol extract from Murraya koenigii leaves (127??gmL?1), acetone extracts from C. longa rhizome (7.4??gmL?1) and Tribulus terrestris seeds (511??gmL?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. PMID:20953430

Ponnusamy, Sudha; Ravindran, Remya; Zinjarde, Smita; Bhargava, Shobha; Ravi Kumar, Ameeta

2011-01-01

184

Evaluation of traditional Indian antidiabetic medicinal plants for human pancreatic amylase inhibitory effect in vitro.  

PubMed

Pancreatic ?-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 ?-amylase inhibition, in order to assess and evaluate their inhibitory potential on pancreatic ?-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 IC(50) values, namely, cold and hot water extracts from Ficus bengalensis bark (4.4 and 125??gmL(-1)), Syzygium cumini seeds (42.1 and 4.1??gmL(-1)), isopropanol extracts of Cinnamomum verum leaves (1.0??gmL(-1)) and Curcuma longa rhizome (0.16??gmL(-1)). The other 4 extracts exhibited concentration independent inhibition, namely, methanol extract of Bixa orellana leaves (49??gmL(-1)), isopropanol extract from Murraya koenigii leaves (127??gmL(-1)), acetone extracts from C. longa rhizome (7.4??gmL(-1)) and Tribulus terrestris seeds (511??gmL(-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. PMID:20953430

Ponnusamy, Sudha; Ravindran, Remya; Zinjarde, Smita; Bhargava, Shobha; Ravi Kumar, Ameeta

2011-01-01

185

Prenatal stress and inhibitory neuron systems: implications for neuropsychiatric disorders.  

PubMed

Prenatal stress is a risk factor for several psychiatric disorders in which inhibitory neuron pathology is implicated. A growing body of research demonstrates that inhibitory circuitry in the brain is directly and persistently affected by prenatal stress. This review synthesizes research that explores how this early developmental risk factor impacts inhibitory neurons and how these findings intersect with research on risk factors and inhibitory neuron pathophysiology in schizophrenia, anxiety, autism and Tourette syndrome. The specific impact of prenatal stress on inhibitory neurons, particularly developmental mechanisms, may elucidate further the pathophysiology of these disorders. PMID:24751963

Fine, R; Zhang, J; Stevens, H E

2014-06-01

186

Screening of tea extract and theaflavins for inhibitory effects on the biological activity and production of staphylococcal enterotoxin A.  

PubMed

This study aimed to develop a novel method with tea extracts and its components, to reduce the risk of foodborne illnesses caused by the bacterial toxin staphylococcal enterotoxin A (SEA). The potential effect of tea extracts, theaflavins, and epitheaflagallin on staphylococcal growth was studied. A broth microdilution method was used to determine the minimum inhibitory concentration of these samples against an SEA-producing strain, Staphylococcus aureus C-29. The following assays were performed to evaluate various effects on concentrations of no effect on staphylococcal growth. The interactions of theaflavin-rich green tea extracts (TGE), theaflavins, and epitheaflagallin to cultured S. aureus C-29 were determined using Western blot analysis. As a result, all samples suppressed the binding affinity of the anti-SEA antibody to SEA. Since these samples could react directly with SEA, we examined whether they could bind to SEA. Our results demonstrated that binding of the anti-SEA antibody to 4 theaflavins-treated SEA was inhibited in a dose-dependent manner. On the other hand, the production of SEA was significantly decreased by treatment with TGE and epitheaflagallin. Based on the finding that TGE and epitheaflagallin inhibit the production of SEA, we further examined the relative expression levels of sea toxin-encoding genes after treatment with TGE and epitheaflagallin with real-time RT-PCR. TGE and epitheaflagallin significantly supressed the gene transcription of SEA in S. aureus C-29. We then tested whether the samples block the biological activity of SEA in murine spleen cells. TGE, theaflavins, and epitheaflagallin became inactivated the biological activity of SEA. These results suggest that edible and safe compounds in tea can be used to inactivate both pathogens and toxins. PMID:25307624

Shimamura, Yuko; Aoki, Natsumi; Sugiyama, Yuka; Nakayama, Tsutomu; Masuda, Shuichi

2014-11-01

187

Inhibitory effects on bacterial growth and beta-ketoacyl-ACP reductase by different species of maple leaf extracts and tannic acid.  

PubMed

It is important to develop new antibiotics aimed at novel targets. The investigation found that the leaf extracts from five maples (Acer platanoides, Acer campestre, Acer rubrum, Acer saccharum and Acer truncatum Bunge collected in Denmark, Canada and China) and their component tannic acid displayed antibacterial ability against 24 standard bacteria strains with the minimum inhibitory concentration of 0.3-8.0 mg/mL. Unlike the standard antibiotic levofloxacin (LFX), these samples inhibited Gram-positive bacteria more effectively than they inhibited Gram-negative bacteria. These samples effectively inhibited two antidrug bacterial strains. The results show that these samples inhibit bacteria by a different mechanism from LFX. These samples potently inhibited b-ketoacyl-ACP reductase (FabG), which is an important enzyme in bacterial fatty acid synthesis. Tannic acid showed the strongest inhibition on FabG with a half inhibition concentration of 0.78 microM (0.81 microg/mL). Furthermore, tannic acid and two maple leaf extracts showed time-dependent irreversible inhibition of FabG. These three samples also exhibited better inhibition on bacteria. It is suggested that FabG is the antibacteria target of maple leaf extracts and tannic acid, and both reversible and irreversible inhibitions of FabG are important for the antibacterial effect. PMID:19444866

Wu, Dan; Wu, Xiao-Dong; You, Xue-Fu; Ma, Xiao-Feng; Tian, Wei-Xi

2010-01-01

188

Elevated Vancomycin Trough Concentration: Increased Efficacy and/or Toxicity?  

PubMed Central

Vancomycin susceptibility of methicillin-resistant Staphylococcus aureus has been changed over time and its average minimum inhibitory concentration increased from 1.5 to 1.75 mg/L.A recently published guideline by the American Society of Health Pharmacist recommended a daily dose of 15-20 mg/Kg every 8 to 12 hours of vancomycin to achieve a trough concentration between 15-20 mg/L for treatment of severe infections. Medical records of 69 patients from infectious ward of Imam Khomeini hospital, with suspected or confirmed gram-positive infection who had at least one trough level of vancomycin, were evaluated regarding vancomycin therapeutic goal; efficacy and renal safety. Most of patients (60.6%) with severe infections did not achieve the recommended vancomycin trough level during treatment course. Time to normalization of the signs and symptoms of infection did not correlate with the patients’ serum vancomycin trough levels. At the end of treatment course, there was no significant correlation between patients’ creatinine clearance and vancomycin trough levels (P=0.32). However, patients’cratinine clearance showed a negatively significant correlation with trough level of vancomycin (P=0.01). Vancomycin induced nephrotoxicity was detected in 4.3% of the patients. These data showed that vancomycin trough level may not necessarily assure treatment success, and also it would not essentially predict the risk of vancomycin induced nephrotoxicity. However, more well designed studies with larger sample size needed for better clinical and practical judgment. PMID:25587313

Elyasi, Sepideh; Khalili, Hossein; Dashti-Khavidaki, Simin; Emadi-Koochak, Hamid; Mohammadpour, Amirhooshang; Abdollahi, Alireza

2014-01-01

189

Inhibitory effects of pepstatin A and mefloquine on the growth of Babesia parasites.  

PubMed

We evaluated the inhibitory effects of pepstatin A and mefloquine on the in vitro and in vivo growths of Babesia parasites. The in vitro growth of Babesia bovis, B. bigemina, B. caballi, and B. equi was significantly inhibited (P < 0.05) by micromolar concentrations of pepstatin A (50% inhibitory concentrations = 38.5, 36.5, 17.6, and 18.1 ?M, respectively) and mefloquine (50% inhibitory concentrations = 59.7, 56.7, 20.7, and 4 ?M, respectively). Furthermore, both reagents either alone at a concentration of 5 mg/kg or in combinations (2.5/2.5 and 5/5 mg/kg) for 10 days significantly inhibited the in vivo growth of B. microti in mice. Mefloquine treatment was highly effective and the combination treatments were less effective than other treatments. Therefore, mefloquine may antagonize the actions of pepstatin A against babesiosis and aspartic proteases may play an important role in the asexual growth cycle of Babesia parasites. PMID:22890034

Munkhjargal, Tserendorj; AbouLaila, Mahmoud; Terkawi, Mohamad Alaa; Sivakumar, Thillaiampalam; Ichikawa, Madoka; Davaasuren, Batdorj; Nyamjargal, Tserendorj; Yokoyama, Naoaki; Igarashi, Ikuo

2012-10-01

190

Inhibitory Effects of Pepstatin A and Mefloquine on the Growth of Babesia Parasites  

PubMed Central

We evaluated the inhibitory effects of pepstatin A and mefloquine on the in vitro and in vivo growths of Babesia parasites. The in vitro growth of Babesia bovis, B. bigemina, B. caballi, and B. equi was significantly inhibited (P < 0.05) by micromolar concentrations of pepstatin A (50% inhibitory concentrations = 38.5, 36.5, 17.6, and 18.1 ?M, respectively) and mefloquine (50% inhibitory concentrations = 59.7, 56.7, 20.7, and 4 ?M, respectively). Furthermore, both reagents either alone at a concentration of 5 mg/kg or in combinations (2.5/2.5 and 5/5 mg/kg) for 10 days significantly inhibited the in vivo growth of B. microti in mice. Mefloquine treatment was highly effective and the combination treatments were less effective than other treatments. Therefore, mefloquine may antagonize the actions of pepstatin A against babesiosis and aspartic proteases may play an important role in the asexual growth cycle of Babesia parasites. PMID:22890034

Munkhjargal, Tserendorj; AbouLaila, Mahmoud; Terkawi, Mohamad Alaa; Sivakumar, Thillaiampalam; Ichikawa, Madoka; Davaasuren, Batdorj; Nyamjargal, Tserendorj; Yokoyama, Naoaki; Igarashi, Ikuo

2012-01-01

191

Minimum Bayes risk image correlation  

NASA Technical Reports Server (NTRS)

In this paper, the problem of designing a matched filter for image correlation will be treated as a statistical pattern recognition problem. It is shown that, by minimizing a suitable criterion, a matched filter can be estimated which approximates the optimum Bayes discriminant function in a least-squares sense. It is well known that the use of the Bayes discriminant function in target classification minimizes the Bayes risk, which in turn directly minimizes the probability of a false fix. A fast Fourier implementation of the minimum Bayes risk correlation procedure is described.

Minter, T. C., Jr.

1980-01-01

192

Ceramic veneers with minimum preparation  

PubMed Central

The aim of this article is to describe the possibility of improving dental esthetics with low-thickness glass ceramics without major tooth preparation for patients with small to moderate anterior dental wear and little discoloration. For this purpose, a carefully defined treatment planning and a good communication between the clinician and the dental technician helped to maximize enamel preservation, and offered a good treatment option. Moreover, besides restoring esthetics, the restorative treatment also improved the function of the anterior guidance. It can be concluded that the conservative use of minimum thickness ceramic laminate veneers may provide satisfactory esthetic outcomes while preserving the dental structure. PMID:24932126

da Cunha, Leonardo Fernandes; Reis, Rachelle; Santana, Lino; Romanini, Jose Carlos; Carvalho, Ricardo Marins; Furuse, Adilson Yoshio

2013-01-01

193

Evaluation of 147 Kampo prescriptions as novel protein tyrosine phosphatase 1B (PTP1B) inhibitory agents  

PubMed Central

Background Protein tyrosine phosphatase (PTP) 1B, a negative regulator of the insulin and leptin signaling pathways, is currently considered a promising target for the development of novel therapeutic approaches used to treat insulin-resistant type 2 diabetes mellitus (IR-T2DM). In this study, we examined the PTP1B inhibitory activity of 147 Japanese prescription Kampo formulations to evaluate their potential for clinical application in IR-T2DM treatment. Methods We specifically defined the prescribed daily dose as 1 Unit (U), and 147 Japanese prescription Kampo formulations were screened for PTP1B inhibitory activity at a final concentration of 0.1 mU/mL. We investigated the dependence of the inhibitory activity on the concentration of the Kampo formulations that exhibited high PTP1B inhibitory activity. Their inhibition mode by kinetic analysis, inhibitory selectivities against four homologous PTPs (TCPTP, VHR, SHP-1 and SHP-2) and cellular activity in the insulin-signaling pathway by increasing the insulin-stimulated Akt phosphorylation level in human hepatocellular liver carcinoma HepG2 cells, were also investigated. The statistical partial least squares regression method was used to identify the crude drugs with the greatest contribution to the PTP1B inhibitory activity of the Kampo formulations. Results Daiokanzoto, Masiningan, Tokakujokito, Keimakakuhanto and Choijokito exhibited high PTP1B inhibitory activity, which was concentration-dependent. Daiokanzoto, Masiningan and Tokakujokito inhibited PTP1B by mixed inhibition modes and exhibited different inhibitory selectivities against four homologous PTPs. Masiningan also exhibited cellular activity. Statistical analyses indicated that the constituent crude drug Rhei Rhizoma provided the greatest contribution to the PTP1B inhibitory activity of these Kampo formulations. Conclusions High PTP1B inhibitory activity was predominantly associated with formulations that were classified as Jyokito in Kampo medicine and with a modern clinical indication of constipation. Currently, there is no clinical treatment for IR-T2DM that uses a mechanism of action based on PTP1B inhibition. Thus, we propose the Kampo formulations identified in this study as strong PTP1B inhibitors, which could be developed as clinical therapeutic agents to treat IR-T2DM. PMID:24555682

2014-01-01

194

Anaerobic biodegradability and inhibitory effects of some anionic and cationic surfactants.  

PubMed

The anaerobic biodegradability and inhibitory effects on the methane production of three different surfactants, two anionic: sodium lauryl sulfate (SLS) and sodium dodecylbenzene sulfonate (SDBS), and a cationic surfactant: trialkyl-methylammonium chloride (TMAC), were evaluated with two different anaerobic sludges, granular and flocculent. Five different concentrations of the surfactants, 5, 50, 100, 250 and 500 mg/L, were tested. SLS was biodegraded at concentrations of 5, 50 and 100 mg/L with flocculent sludge and at 100 and 250 mg/L with granular sludge. However an inhibitory effect on methane production was observed in both sludges at 500 mg/L. The results indicate that SDBS was not biodegradable under anoxic conditions. TMAC was slightly degraded 50 and 100 mg/L with the flocculent sludge, and from 100 to 500 mg/L with the granular sludge. PMID:20686749

Pérez-Armendáriz, Beatriz; Moreno, Yésica Mayett; Monroy-Hermosillo, Oscar; Guyot, Jean Pierre; González, Rosa O

2010-09-01

195

49 CFR 639.27 - Minimum criteria.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Minimum criteria. 639.27 Section...TRANSPORTATION CAPITAL LEASES Cost-Effectiveness § 639.27 Minimum criteria. In making...appropriate: (a) Operation costs; (b) Reliability of...

2010-10-01

196

49 CFR 639.27 - Minimum criteria.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Minimum criteria. 639.27 Section...TRANSPORTATION CAPITAL LEASES Cost-Effectiveness § 639.27 Minimum criteria. In making...appropriate: (a) Operation costs; (b) Reliability of...

2011-10-01

197

Minimum cut and shear bands  

NASA Astrophysics Data System (ADS)

We explore the efficacy of network optimisation theory for minimum cut to quantify the evolution of granular fabric and its functionality as a transmission medium in deforming dense granular media. Our focus here is on force transmission in a sheared assembly of polydisperse particles, in a biaxial compression test under constant confining pressure. The granular fabric is examined with respect to the material's force-bearing contact network over that regime when the material has reached its residual strength, and is deforming under a near constant volume in the presence of a fully developed shear band. The structural evolution of the fabric is quantitatively characterized using a representative weighted-directed network that is similarly evolving as the sample deforms. The edges or links, representing the interparticle contacts, are each weighted by the capacity of the contact to transmit force: a scalar that depends solely on the relative motion of the contacting grains. In the large strain failure regime, the minimum cut which represents the bottleneck in force transmission is found to lie in the persistent shear band. This study paves the way for the future analysis of flows and force transmission through an evolving contact network and, in turn, the characterisation of the relationship between the material's contact topology and its capacity to transmit forces through its contact network.

Tordesillas, Antoinette; Cramer, Andrew; Walker, David M.

2013-06-01

198

In vitro inhibitory effect of cranberry ( Vaccinium macrocarpum Ait.) juice on pathogenic microorganisms  

Microsoft Academic Search

The purpose of this study was to determine the inhibitory effects of cranberry juice on pathogenic microorganisms. The microorganisms\\u000a analyzed were Escherichia coli from patients with urinary infections, Salmonella spp., Listeria monocytogenes, Pseudomona aeruginosa, and Staphylococcus aureus. The disc method was used to determine the sensitivity of bacteria to cranberry juice (CJ, both concentrated and diluted).\\u000a A lawn of 106

H. L. E. Magarińos; C. Sahr; S. D. C. Selaive; M. E. Costa; F. E. Figuerola; O. A. Pizarro

2008-01-01

199

Synthesis and HIV-1 integrase inhibitory activities of caffeic acid dimers derived from Salvia officinalis.  

PubMed

The synthesis of two caffeoyl-coumarin conjugates, derived from sagecoumarin, has been accomplished, starting from ferulic acid, isoferulic acid and sesamol. Both compounds exhibited potent inhibitory activities at micromolar concentrations against HIV-1 integrase in 3'-end processing reaction but were less effective against HIV-1 replication in a single-round infection assay of HeLa-beta-gal-CD4+ cells. PMID:16183277

Bailly, Fabrice; Queffelec, Clémence; Mbemba, Gladys; Mouscadet, Jean-François; Cotelle, Philippe

2005-11-15

200

Robust microcircuit synchronization by inhibitory connections  

PubMed Central

SUMMARY Microcircuits in different brain areas share similar architectural and biophysical properties with compact motor network known as central pattern generators (CPGs). Consequently, CPGs have been suggested as valuable biological models for the understanding of microcircuit dynamics and particularly, their synchronization. In the present paper we use a well known compact motor network, the lobster pyloric CPG to study principles of intercircuit synchronization. We couple separate pyloric circuits obtained from two animals via artificial synapses and observe how their synchronization depends on the topology and kinetic parameters of the computer-generated synapses. Stable in-phase synchronization appears when electrically coupling the pacemaker groups of the two networks, but reciprocal inhibitory connections produce more robust and regular cooperative activity. Contralateral inhibitory connections offer effective synchronization and flexible setting of the burst phases of the interacting networks. We also show that a conductance-based mathematical model of the coupled circuits correctly reproduces the observed dynamics illustrating the generality of the phenomena. PMID:19217380

Szücs, Attila; Huerta, Ramon; Rabinovich, Mikhail I.; Selverston, Allen I.

2009-01-01

201

New cholinesterase inhibitory constituents from Lonicera quinquelocularis.  

PubMed

A phytochemical investigation on the ethyl acetate soluble fraction of Lonicera quinquelocularis (whole plant) led to the first time isolation of one new phthalate; bis(7-acetoxy-2-ethyl-5-methylheptyl) phthalate (3) and two new benzoates; neopentyl-4-ethoxy-3, 5-bis (3-methyl-2-butenyl benzoate (4) and neopentyl-4-hydroxy-3, 5-bis (3-methyl-2-butenyl benzoate (5) along with two known compounds bis (2-ethylhexyl phthalate (1) and dioctyl phthalate (2). Their structures were established on the basis of spectroscopic analysis and by comparison with available data in the literature. All the compounds (1-5) were tested for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities in dose dependent manner. The IC50 (50% inhibitory effect) values of compounds 3 and 5 against AChE were 1.65 and 3.43 µM while the values obtained against BChE were 5.98 and 9.84 µM respectively. Compounds 2 and 4 showed weak inhibition profile. PMID:24733024

Khan, Dilfaraz; Khan, Hidayat Ullah; Khan, Farmanullah; Khan, Shafiullah; Badshah, Syed; Khan, Abdul Samad; Samad, Abdul; Ali, Farman; Khan, Ihsanullah; Muhammad, Nawshad

2014-01-01

202

New Cholinesterase Inhibitory Constituents from Lonicera quinquelocularis  

PubMed Central

A phytochemical investigation on the ethyl acetate soluble fraction of Lonicera quinquelocularis (whole plant) led to the first time isolation of one new phthalate; bis(7-acetoxy-2-ethyl-5-methylheptyl) phthalate (3) and two new benzoates; neopentyl-4-ethoxy-3, 5-bis (3-methyl-2-butenyl benzoate (4) and neopentyl-4-hydroxy-3, 5-bis (3-methyl-2-butenyl benzoate (5) along with two known compounds bis (2-ethylhexyl phthalate (1) and dioctyl phthalate (2). Their structures were established on the basis of spectroscopic analysis and by comparison with available data in the literature. All the compounds (1–5) were tested for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities in dose dependent manner. The IC50 (50% inhibitory effect) values of compounds 3 and 5 against AChE were 1.65 and 3.43 µM while the values obtained against BChE were 5.98 and 9.84 µM respectively. Compounds 2 and 4 showed weak inhibition profile. PMID:24733024

Khan, Dilfaraz; Khan, Hidayat Ullah; Khan, Farmanullah; Khan, Shafiullah; Badshah, Syed; Khan, Abdul Samad; Samad, Abdul; Ali, Farman; Khan, Ihsanullah; Muhammad, Nawshad

2014-01-01

203

Minimum-energy mobile wireless networks revisited  

Microsoft Academic Search

We propose a protocol that, given a communication network, computes a subnetwork such that, for every pair (u, υ) of nodes connected in the original network, there is a a minimum-energy path between u and υ in the subnetwork (where a minimum-energy path is one that allows messages to be transmitted with a minimum use of energy). The network computed

Li Li; J. Y. Halpern

2001-01-01

204

Mining association rules with multiple minimum supports  

Microsoft Academic Search

Association rule mining is an important model in data mining. Its mining algorithms discover all it em associations (or r ules) in the data that satisfy the user-specified minimum support (minsup) and minimum confidence (minconf) constraints. Minsup controls the minimum number of data ca ses that a rule must cover. Minconf controls the predictive strength of the rule. Since only

Bing Liu; Wynne Hsu; Yiming Ma

1999-01-01

205

Inhibitory Plasticity Dictates the Sign of Plasticity at Excitatory Synapses  

PubMed Central

The broad connectivity of inhibitory interneurons and the capacity of inhibitory synapses to be plastic make them ideal regulators of the level of excitability of many neurons simultaneously. Whether inhibitory synaptic plasticity may also contribute to the selective regulation of single neurons and local microcircuits activity has not been investigated. Here we demonstrate that in rat primary visual cortex inhibitory synaptic plasticity is connection specific and depends on the activation of postsynaptic GABAB–Gi/o protein signaling. Through the activation of this intracellular signaling pathway, inhibitory plasticity can alter the state of a single postsynaptic neuron and directly affect the induction of plasticity at its glutamatergic inputs. This interaction is modulated by sensory experience. Our data demonstrate that in recurrent circuits, excitatory and inhibitory forms of synaptic plasticity are not integrated as independent events, but interact to cooperatively drive the activity-dependent rewiring of local microcircuits. PMID:24453301

Wang, Lang

2014-01-01

206

Molecular docking studies and in vitro cholinesterase enzyme inhibitory activities of chemical constituents of Garcinia hombroniana.  

PubMed

Garcinia species are reported to possess antimicrobial, anti-inflammatory, anticancer, anti-HIV and anti-Alzheimer's activities. This study aimed to investigate the in vitro cholinesterase enzyme inhibitory activities of garcihombronane C (1), garcihombronane F (2), garcihombronane I (3), garcihombronane N (4), friedelin (5), clerosterol (6), spinasterol glucoside (7) and 3?-hydroxy lup-12,20(29)-diene (8) isolated from Garcinia hombroniana, and to perform molecular docking simulation to get insight into the binding interactions of the ligands and enzymes. The cholinesterase inhibitory activities were evaluated using acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. In this study, compound 4 displayed the highest concentration-dependent inhibition of both AChE and BChE. Docking studies exhibited that compound 4 binds through hydrogen bonds to amino acid residues of AChE and BChE. The calculated docking and binding energies also supported the in vitro inhibitory profiles of IC50. In conclusion, garcihombronanes C, F, I and N (1-4) exhibited dual and moderate inhibitory activities against AChE and BChE. PMID:25219673

Jamila, Nargis; Yeong, Khaw Kooi; Murugaiyah, Vikneswaran; Atlas, Amir; Khan, Imran; Khan, Naeem; Khan, Sadiq Noor; Khairuddean, Melati; Osman, Hasnah

2015-01-01

207

Dual inhibitory effect of Glycyrrhiza glabra (GutGard™) on COX and LOX products.  

PubMed

Glycyrrhiza glabra and its phytoconstituents have been known to possess widespread pharmacological properties as an anti-inflammatory, anti-viral, antitumour and hepatoprotective drug. In this study, we examined the inhibitory potential of extract of G. glabra (GutGard™) root and its phytoconstituents (glabridin, glycyrrhizin, and isoliquiritigenin) on both cyclooxygenase (COX) and lipoxygenase (LOX) products in order to understand the mechanism of its anti-inflammatory action. Inhibitory effect of GutGard™ and its phytoconstituents on lipopolysaccharide (LPS) induced prostaglandin E(2) (PGE(2)), calcimycin (A23187) induced thromboxane (TXB(2)), and leukotriene (LTB(4)) release was studied using murine macrophages (J774A.1) and human neutrophil (HL-60) cells. Results revealed that, G. glabra and glabridin significantly inhibited PGE(2), TXB(2) (COX) and LTB(4) (LOX), while, isoliquiritigenin exerted inhibitory effect only against COX products but failed to suppress LOX product. However, glycyrrhizin at the tested concentrations failed to exhibit inhibitory effect on both COX and LOX products. Here, we report for the first time that G. glabra (almost devoid of glycyrrhizin) exhibits anti-inflammatory property likely through the inhibition of PGE(2), TXB(2) and LTB(4) in mammalian cell assay system, which could be influenced in part by glabridin and isoliquiritigenin. PMID:20864324

Chandrasekaran, C V; Deepak, H B; Thiyagarajan, P; Kathiresan, S; Sangli, Gopal Krishna; Deepak, M; Agarwal, Amit

2011-02-15

208

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

PubMed Central

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. PMID:22969825

Watanabe, Yuka; Ikarashi, Nobutomo; Satoh, Toshiyuki; Ito, Kiyomi; Ochiai, Wataru; Sugiyama, Kiyoshi

2012-01-01

209

Acethylcholinesterase inhibitory potential and antioxidant properties of pyrogallol.  

PubMed

Abstract Pyrogallol is found naturally in crops and fruits of many plants. It is also an active ingredient of many pharmaceuticals. For this reason, we employed different in vitro antioxidant assays such as cupric ion Cu(2+) reducing power, Fe(3+) reducing power, total antioxidant activity by ferric thiocyanate method, ABTS radical scavenging, DMPD radical scavenging, DPPH • scavenging, Fe(2+) chelating, [Formula: see text] scavenging and H2O2 scavenging activities of pyrogallol. Pyrogallol inhibited 77.95% lipid peroxidation of linoleic acid emulsion at 30??g/mL concentration. BHA, BHT, ?-tocopherol and trolox exhibited inhibitions of 89.88, 89.97, 83.82 and 91.85% against peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, pyrogallol was an effective of all the scavenging and reducing power results. In this study, pyrogallol was also evaluated as potential inhibitor for acethycholinesterse enzyme. The results showed that pyrogallol exhibited potent acetylcholinesteras inhibitory activity with IC50 and Ki values 10.2 and 8.6??M, respectively. PMID:25297710

Ozturk Sarikaya, S Beyza

2014-10-01

210

Minimum distance classification in remote sensing  

NASA Technical Reports Server (NTRS)

The utilization of minimum distance classification methods in remote sensing problems, such as crop species identification, is considered. Literature concerning both minimum distance classification problems and distance measures is reviewed. Experimental results are presented for several examples. The objective of these examples is to: (a) compare the sample classification accuracy of a minimum distance classifier, with the vector classification accuracy of a maximum likelihood classifier, and (b) compare the accuracy of a parametric minimum distance classifier with that of a nonparametric one. Results show the minimum distance classifier performance is 5% to 10% better than that of the maximum likelihood classifier. The nonparametric classifier is only slightly better than the parametric version.

Wacker, A. G.; Landgrebe, D. A.

1972-01-01

211

Inhibitory connections in the assembly neural network for texture segmentation.  

PubMed

A neural network with assembly organization is described. This assembly network is applied to the problem of texture segmentation in natural scenes. The network is partitioned into several subnetworks: one for each texture class. Hebb's assemblies are formed in the subnetworks during the process of training the excitatory connections. Also, a structure of the inhibitory connections is formed in the assembly network during a separate training process. The inhibitory connections result in inhibitory interactions between different subnetworks. Computer simulation of the network has been performed. Experiments show that an adequately trained assembly network with inhibitory connections is more efficient than without them. PMID:12662796

Goltsev, Alexander; Wunsch, Donald C.

1998-07-01

212

Morphological, Biochemical and Molecular Characterization of Twelve Nitrogen-Fixing Bacteria and Their Response to Various Zinc Concentration  

PubMed Central

Background: Zinc is an essential micronutrient used in the form of zinc sulfate in fertilizers in the agriculture production system. Nitrogen-fixing microorganisms are also of considerable value in promoting soil fertility. Objectives: This study aimed to investigate the degree of sensitivity to varying concentrations of zinc, in the form of ZnSO4, in different strains of Azotobacter chroococcum in a laboratory environment. Materials and Methods: To isolate A. chroococcum strains, soil samples were collected from wheat, corn and asparagus rhizospheres and cultured in media lacking nitrogen at 30?C for 48 hours. Strains were identified based on morphological and biochemical characteristics. The presence of the nitrogenase enzyme system was confirmed by testing for the presence of the nifH gene using PCR analysis. The minimum inhibitory concentration (MIC) and optimal zinc concentration for the growth of each strain was determined. Results: A total of 12 bacterial strains were isolated from six different soil samples. A. chroococcum strains were morphologically and biochemically characterized. The presence of the nifH gene was confirmed in all the strains. MIC and the optimal zinc concentration for bacterial growth were 50 ppm and 20 ppm, respectively. Conclusions: It was concluded that increasing the concentration of zinc in the agricultural soil is harmful to beneficial microorganisms and reduces the soil fertility. A 20-ppm zinc concentration in soil is suggested to be optimal. PMID:25147702

Dadook, Mohammad; Mehrabian, Sedigheh; Salehi, Mitra; Irian, Saeed

2014-01-01

213

Do Minimum Wage Hikes Raise US Long Term Unemployment? Evidence Using State Minimum Wage Rates  

Microsoft Academic Search

PARTRIDGE M. D. and PARTRIDGE J. S. (1999) Do minimum wage hikes raise US long term unemployment? Evidence using state minimum wage rates, Reg. Studies 33 , 713?726. Several recent studies have challenged the conventional notion that raising the minimum wage reduces employment. This study considers a related but relatively unexplored issue by examining the minimum wage's influence on long

Mark D. Partridge; Jamie S. Partridge

1999-01-01

214

Elliptical concentrators.  

PubMed

Nonimaging optics is a field devoted to the design of optical components for applications such as solar concentration or illumination. In this field, many different techniques have been used to produce optical devices, including the use of reflective and refractive components or inverse engineering techniques. However, many of these optical components are based on translational symmetries, rotational symmetries, or free-form surfaces. We study a new family of nonimaging concentrators called elliptical concentrators. This new family of concentrators provides new capabilities and can have different configurations, either homofocal or nonhomofocal. Translational and rotational concentrators can be considered as particular cases of elliptical concentrators. PMID:17068595

Garcia-Botella, Angel; Fernandez-Balbuena, Antonio Alvarez; Bernabeu, Eusebio

2006-10-10

215

A lectin with highly potent inhibitory activity toward breast cancer cells from edible tubers of Dioscorea opposita cv. nagaimo.  

PubMed

A 70-kDa galactose-specific lectin was purified from the tubers of Dioscorea opposita cv. nagaimo. The purification involved three chromatographic steps: anion exchange chromatography on a Q-Sepharose column, FPLC-anion exchange chromatography on a Mono Q column, and FPLC-gel filtration on a Superdex 75 column. The purified nagaimo lectin presented as a single 35-kDa band in reducing SDS-PAGE while it exhibited a 70-kDa single band in non-reducing SDS-PAGE suggesting its dimeric nature. Nagaimo lectin displayed moderate thermostability, retaining full hemagglutinating activity after heating up to 62°C for 30 minutes. It also manifested stability over a wide pH range from pH 2 to 13. Nagaimo lectin was a galactose-specific lectin, as evidenced by binding with galactose and galactose-containing sugars such as lactose and raffinose. The minimum concentration of galactose, lactose and raffinose required to exert an inhibitory effect on hemagglutinating activity of nagaimo lectin was 20 mM, 5 mM and 40 mM, respectively. Nagaimo lectin inhibited the growth of some cancer cell lines including breast cancer MCF7 cells, hepatoma HepG2 cells and nasopharyngeal carcinoma CNE2 cells, with IC(50) values of 3.71 µM, 7.12 µM and 19.79 µM, respectively, after 24 hour treatment with nagaimo lectin. The induction of phosphatidylserine externalization and mitochondrial depolarization indicated that nagaimo lectin evoked apoptosis in MCF7 cells. However, the anti-proliferative activity of nagaimo lectin was not blocked by application of galactose, signifying that the activity was not related to the carbohydrate binding specificity of the lectin. PMID:23349827

Chan, Yau Sang; Ng, Tzi Bun

2013-01-01

216

New lipoxygenase inhibitory sphingolipids from Chrozophora plicata.  

PubMed

Two new sphingolipids plicatin A [(2S,3S,4R)-2-{[(2R)-2-hydroxyoctdecanoyl]amino}hexaeicosane-1,3,4-triol (1)] and plicatin B [(2S,3S,4R,10E)-2-{[(2R)-2-hydroxyoctdecanoyl]amino}tricont-10-ene-1,3,4-triol (2)], together with 4-hydroxybenzaldehyde, scopoletin, uracil, and dl-threonolactone were isolated from the methanolic extract of the whole plant of Chrozophora plicata. The structures of these compounds were established using 1D ((1)H, (13)C) and 2D NMR (HMQC, HMBC, and COSY) spectroscopy and mass spectrometry (EI-MS and HR-EI-MS) and in comparison with the reported data in the literature. Compounds 1 and 2 showed inhibitory potential against enzyme lipoxygenase with IC50 values 195.1 and 102.3 ?M, respectively. PMID:23822213

Riaz, Naheed; Tabussum, Asia; Saleem, Muhammad; Ashraf, Muhammad; Nasar, Romana; Jabeen, Bushra; Malik, Abdul; Jabbar, Abdul

2013-01-01

217

Timing control by redundant inhibitory neuronal circuits  

NASA Astrophysics Data System (ADS)

Rhythms and timing control of sequential activity in the brain is fundamental to cognition and behavior. Although experimental and theoretical studies support the understanding that neuronal circuits are intrinsically capable of generating different time intervals, the dynamical origin of the phenomenon of functionally dependent timing control is still unclear. Here, we consider a new mechanism that is related to the multi-neuronal cooperative dynamics in inhibitory brain motifs consisting of a few clusters. It is shown that redundancy and diversity of neurons within each cluster enhances the sensitivity of the timing control with the level of neuronal excitation of the whole network. The generality of the mechanism is shown to work on two different neuronal models: a conductance-based model and a map-based model.

Tristan, I.; Rulkov, N. F.; Huerta, R.; Rabinovich, M.

2014-03-01

218

Neural correlates of inhibitory deficits in depression  

PubMed Central

The present study was designed to examine neural correlates of inhibitory dysfunction in individuals diagnosed with Major Depressive Disorder (MDD). Twelve MDD participants and 12 never-depressed controls completed the negative affective priming (NAP) task in the scanner. Results indicated that, in depressed participants, increased activation in the rostral anterior cingulate cortex (rACC) is associated with inhibition of negative, but not positive, words; in contrast, in nondepressed participants, inhibition of positive, but not negative, words is associated with increased activation in the rACC. These findings indicate that abnormalities in neural function, especially in the rACC, may underlie difficulties experienced by depressed individuals in inhibiting negative thoughts. These results underscore the importance of continuing to examine the relation between cognitive and neural functioning in depression in order to gain a broader and more integrative understanding of this disorder. PMID:19962859

Eugčne, Fanny; Joormann, Jutta; Cooney, Rebecca E.; Atlas, Lauren Y.; Gotlib, Ian H.

2009-01-01

219

Timing control by redundant inhibitory neuronal circuits  

SciTech Connect

Rhythms and timing control of sequential activity in the brain is fundamental to cognition and behavior. Although experimental and theoretical studies support the understanding that neuronal circuits are intrinsically capable of generating different time intervals, the dynamical origin of the phenomenon of functionally dependent timing control is still unclear. Here, we consider a new mechanism that is related to the multi-neuronal cooperative dynamics in inhibitory brain motifs consisting of a few clusters. It is shown that redundancy and diversity of neurons within each cluster enhances the sensitivity of the timing control with the level of neuronal excitation of the whole network. The generality of the mechanism is shown to work on two different neuronal models: a conductance-based model and a map-based model.

Tristan, I., E-mail: itristan@ucsd.edu; Rulkov, N. F.; Huerta, R.; Rabinovich, M. [BioCircuits Institute, University of California, San Diego, La Jolla, California 92093-0402 (United States)] [BioCircuits Institute, University of California, San Diego, La Jolla, California 92093-0402 (United States)

2014-03-15

220

Urease inhibitory constituents from Daphne retusa.  

PubMed

The bioassay-guided fractionation of Daphne retusa Hemsl. has led to the isolation of a new aryl tetrahydronaphthalene lignan derivative named as daphnretusic acid (1), along with six new source compounds such as 5,7-dihydroxyflavone (2), 7-hydroxyflavone (3), 6-methoxyflavone (4), (+) pinoresinol (5), (+) sesamin (6), and ?-sitosterol-3-O-?-D-glucopyranoside (7). Their structures were elucidated by (1)H NMR, (13)C NMR, 1D, 2D NMR, UV, IR, and EIMS analyses. All the fractions (n-hexane, CHCl3, AcOEt, CH3OH, and water) and pure compounds (1-7) were subjected to the assay of urease and ?-chymotrypsin inhibitory activities. Chloroform and methanol soluble fractions showed moderate urease inhibition. Compound 2 exhibited significant urease inhibition with IC50 value 60.4 ± 0.72 ?M, whereas compounds 1 and 3-7 remained inactive during urease inhibition and ?-chymotrypsin bioassays. PMID:24266421

Mansoor, Farrukh; Anis, Itrat; Khan, Ajmal; Marasini, Bishnu P; Choudhary, Muhammad Iqbal; Shah, Muhammad Raza

2014-01-01

221

Impaired Inhibitory Control in Recreational Cocaine Users  

PubMed Central

Chronic use of cocaine is associated with impairment in response inhibition but it is an open question whether and to which degree findings from chronic users generalize to the upcoming type of recreational users. This study compared the ability to inhibit and execute behavioral responses in adult recreational users and in a cocaine-free-matched sample controlled for age, race, gender distribution, level of intelligence, and alcohol consumption. Response inhibition and response execution were measured by a stop-signal paradigm. Results show that users and non users are comparable in terms of response execution but users need significantly more time to inhibit responses to stop-signals than non users. Interestingly, the magnitude of the inhibitory deficit was positively correlated with the individuals lifetime cocaine exposure suggesting that the magnitude of the impairment is proportional to the degree of cocaine consumed. PMID:17989775

Colzato, Lorenza S.; van den Wildenberg, Wery P. M.; Hommel, Bernhard

2007-01-01

222

Epithelial chloride channel. Development of inhibitory ligands  

PubMed Central

Chloride channels are present in the majority of epithelial cells, where they mediate absorption or secretion of NaCl. Although the absorptive and secretory channels are well characterized in terms of their electrophysiological behavior, there is a lack of pharmacological ligands that can aid us in further functional and eventually molecular characterization. To obtain such ligands, we prepared membrane vesicles from bovine kidney cortex and apical membrane vesicles from trachea and found that they contain a chloride transport process that is electrically conductive. This conductance was reduced by preincubating the vesicles in media containing ATP or ATP-gamma-S, but not beta- methylene ATP, which suggests that the membranes contain a kinase that can close the channels. We then screened compounds derived from three classes: indanyloxyacetic acid (IAA), anthranilic acid (AA), and ethacrynic acid. We identified potent inhibitors from the IAA and the AA series. We tritiated IAA-94 and measured binding of this ligand to the kidney cortex membrane vesicles and found a high-affinity binding site whose dissociation constant (0.6 microM) was similar to the inhibition constant (1 microM). There was a good correlation between the inhibitory potency of several IAA derivatives and their efficacy in displacing [3H]IAA-94 from its binding site. Further, other chloride channel inhibitors, including AA derivatives, ethacrynic acid, bumetanide, and DIDS, also displaced the ligand from its binding site. A similar conductance was found in apical membrane vesicles from bovine trachea that was also inhibited by IAA-94 and AA-130B, but the inhibitory effects of these compounds were weaker than their effects on the renal cortex channel. The two drugs were also less potent in displacing [3H]IAA-94 from the tracheal binding site. PMID:2450168

1987-01-01

223

Concise synthesis of (-)-steviamine and analogues and their glycosidase inhibitory activities.  

PubMed

A concise synthesis of (-)-steviamine is reported along with the synthesis of its analogues 10-nor-steviamine, 10-nor-ent-steviamine and 5-epi-ent-steviamine. These compounds were tested against twelve glycosidases (at 143 ?g mL(-1) concentrations) and were found to have in general poor inhibitory activity against most enzymes. The 10-nor analogues however, showed 50-54% inhibition of ?-L-rhamnosidase from Penicillium decumbens while one of these, 10-nor-steviamine, showed 51% inhibition of N-acetyl-?-D-glucosaminidase (from Jack bean) at the same concentration (760 ?M). PMID:23640519

Jiangseubchatveera, Nadechanok; Bouillon, Marc E; Liawruangrath, Boonsom; Liawruangrath, Saisunee; Nash, Robert J; Pyne, Stephen G

2013-06-21

224

AFM study of the differential inhibitory effects of the green tea polyphenol (-)-epigallocatechin-3-gallate (EGCG) against Gram-positive and Gram-negative bacteria.  

PubMed

(-)-Epigallocatechin-3-gallate (EGCG), a main constituent of tea catechins, affects Gram-positive and Gram-negative bacteria differently; however, the underlying mechanisms are not clearly understood. Atomic force microscopy (AFM) was used to compare morphological alterations in Gram-positive and Gram-negative bacteria induced by EGCG and by H(2)O(2) at sub-minimum inhibitory concentrations (MICs). EGCG initially induced aggregates in the cell envelopes of Staphylococcus aureus and eventually caused cell lysis, which was not observed in cells treated with H(2)O(2). It initially induced nanoscale perforations or microscale grooves in the cell envelopes of Escherichia coli O157:H7 which eventually disappeared, similar to E. coli cells treated with H(2)O(2). An E. coli O157:H7 tpx mutant, with a defect in thioredoxin-dependent thiol peroxidase (Tpx), was more severely damaged by EGCG when compared with its wild type. Similar differing effects were observed in other Gram-positive and Gram-negative bacteria when exposed to EGCG; it caused aggregated in Streptococcus mutans, while it caused grooves in Pseudomonas aeruginosa. AFM results suggest that the major morphological changes of Gram-negative bacterial cell walls induced by EGCG depend on H(2)O(2) release. This is not the case for Gram-positive bacteria. Oxidative stress in Gram-negative bacteria induced by EGCG was confirmed by flow cytometry. PMID:22029921

Cui, Y; Oh, Y J; Lim, J; Youn, M; Lee, I; Pak, H K; Park, W; Jo, W; Park, S

2012-02-01

225

Inhibitory Effect of Black and Red Pepper and Thyme Extracts and Essential Oils on Enterohemorrhagic Escherichia coli and DNase Activity of Staphylococcus aureus  

PubMed Central

In this study, extracts and essential oils of Black and Red pepper and Thyme were tested for antibacterial activity against Escherichia coli O157: H7 and Staphylococcus aureus. Black and Red pepper and Thyme were provided from Iranian agricultural researches center. 2 g of each plant powder was added to 10 cc ethanol 96°. After 24 h, the crude extract was separated as an alcoholic extract and concentrated by distillation method. Plants were examined for determining their major component and essential oils were separated. Phytochemical analyses were done for detection of some effective substances in extracts. The antibacterial activity against Escherichia coli O157: H7 and Staphylococcus aureus was tested and the results showed that all extracts and essential oils were effective and essential oils were more active. The extracts and oils that showed antimicrobial activity were later tested to determine the Minimum Inhibitory Dilution (MID) for those bacteria. They were also effective on the inhibition of DNase activity. This study was indicated that extracts and essential oils of Black and Red pepper and Thyme can play a significant role in inhibition of Escherichia coli O157: H7 and Staphylococcus aureus. PMID:24250643

Zarringhalam, Maryam; Zaringhalam, Jalal; Shadnoush, Mehdi; Safaeyan, Firouzeh; Tekieh, Elaheh

2013-01-01

226

A Novel Lectin with Antiproliferative and HIV-1 Reverse Transcriptase Inhibitory Activities from Dried Fruiting Bodies of the Monkey Head Mushroom Hericium erinaceum  

PubMed Central

A lectin designated as Hericium erinaceum agglutinin (HEA) was isolated from dried fruiting bodies of the mushroom Hericium erinaceum with a chromatographic procedure which entailed DEAE-cellulose, CM-cellulose, Q-Sepharose, and FPLC Superdex 75. Its molecular mass was estimated to be 51?kDa and its N-terminal amino acid sequences was distinctly different from those of other isolated mushroom lectins. The hemagglutinating activity of HEA was inhibited at the minimum concentration of 12.5?mM by inulin. The lectin was stable at pH 1.9–12.1 and at temperatures up to 70°C, but was inhibited by Hg2+, Cu2+, and Fe3+ ions. The lectin exhibited potent mitogenic activity toward mouse splenocytes, and demonstrated antiproliferative activity toward hepatoma (HepG2) and breast cancer (MCF7) cells with an IC50 of 56.1??M and 76.5??M, respectively. It manifested HIV-1 reverse transcriptase inhibitory activity with an IC50 of 31.7??M. The lectin exhibited potent mitogenic activity toward murine splenocytes but was devoid of antifungal activity. PMID:20625408

Li, Yanrui; Zhang, Guoqing; Ng, Tzi Bun; Wang, Hexiang

2010-01-01

227

Inhibitory Effect of Black and Red Pepper and Thyme Extracts and Essential Oils on Enterohemorrhagic Escherichia coli and DNase Activity of Staphylococcus aureus.  

PubMed

In this study, extracts and essential oils of Black and Red pepper and Thyme were tested for antibacterial activity against Escherichia coli O157: H7 and Staphylococcus aureus. Black and Red pepper and Thyme were provided from Iranian agricultural researches center. 2 g of each plant powder was added to 10 cc ethanol 96°. After 24 h, the crude extract was separated as an alcoholic extract and concentrated by distillation method. Plants were examined for determining their major component and essential oils were separated. Phytochemical analyses were done for detection of some effective substances in extracts. The antibacterial activity against Escherichia coli O157: H7 and Staphylococcus aureus was tested and the results showed that all extracts and essential oils were effective and essential oils were more active. The extracts and oils that showed antimicrobial activity were later tested to determine the Minimum Inhibitory Dilution (MID) for those bacteria. They were also effective on the inhibition of DNase activity. This study was indicated that extracts and essential oils of Black and Red pepper and Thyme can play a significant role in inhibition of Escherichia coli O157: H7 and Staphylococcus aureus. PMID:24250643

Zarringhalam, Maryam; Zaringhalam, Jalal; Shadnoush, Mehdi; Safaeyan, Firouzeh; Tekieh, Elaheh

2013-01-01

228

Inhibitory effect of a bioactivity-guided fraction from Rheum undulatum on the acid production of Streptococcus mutans biofilms at sub-MIC levels.  

PubMed

Rheum undulatum root has been used traditionally in Korea for the treatment of dental diseases. The purpose of this study was to separate a fraction from R. undulatum showing anti-acid production activity against Streptococcus mutans biofilms and identify the main components in that fraction. Methanol extract of R. undulatum root and its fractions were prepared. To select a fraction exhibiting anti-acid production activity, suspension glycolytic pH-drop assay was performed. Among the fractions tested, dichloromethane fraction exhibited the strongest activity in a dose-dependent manner. To examine the effect of the selected fraction on the anti-acid production of S. mutans biofilms, 74 h old S. mutans biofilms were used. The selected fraction reduced the initial rate of acid production of S. mutans biofilms at sub-minimum inhibitory concentration (MIC) levels. HPLC qualitative analysis of the selected fraction indicated that the presence of anthraquinone derivatives, such as aloe-emodin, emodin, chrysophanol and physcion, as main components. PMID:21059383

Kim, Jeong-Eun; Kim, Hye-Jin; Pandit, Santosh; Chang, Kee-Wan; Jeon, Jae-Gyu

2011-04-01

229

Acetyl- and butyryl-cholinesterase inhibitory activities of the edible brown alga Eisenia bicyclis.  

PubMed

As part of our ongoing isolation of cholinesterase (ChE) inhibitors from natural marine sources, the bioactivity of the ethanolic extracts from 12 Korean seaweeds were screened for their inhibitory activities against acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and total reactive oxygen species (ROS) generation. Eisenia bicyclis exhibited promising inhibitory properties against AChE, BChE and total ROS with inhibition percentages (%) of 68.01 ± 1.37, 95.72 ± 3.80, and 73.20 ± 1.82 at concentrations of 25 µg/mL, respectively. Among the different solvent-soluble fractions obtained from the ethanolic extract, the ethyl acetate (EtOAc) fraction was found to cause the most potent scavenging, or inhibitory activities, against 2,2-diphenyl-1-picrylhydrazyl (DPPH), peroxynitrite (ONOO(-)) and total ROS with the respective IC50 values of 2.48 ± 0.01, 8.70 ± 0.06, and 0.81 ± 0.03 µg/mL. Likewise, the EtOAc fraction also exhibited potent inhibitory activities against AChE and BChE with IC50 values of 2.78 ± 0.07 and 3.48 ± 0.32 µg/mL, respectively. Silica gel column chromatography of the EtOAc fraction yielded a phlorotannin, 974-B, based on the comparison with reported (1)H- and (13)C-NMR spectroscopic data. 974-B showed strong scavenging/or inhibitory potential against DPPH, ONOO(-), total ROS, AChE, and BChE with the respective IC50 values of 0.86 ± 0.02, 1.80 ± 0.01, 6.45 ± 0.04, 1.95 ± 0.01, and 3.26 ± 0.08 µM, respectively. These results indicate that the potential of E. bicyclis and its phlorotannin for use in the development of therapeutic or preventive agents of Alzheimer's disease mainly through ChE inhibition and additional antioxidant capacities. PMID:25370610

Choi, Jae Sue; Haulader, Shourav; Karki, Subash; Jung, Hee Jin; Kim, Hyeung Rak; Jung, Hyun Ah

2014-11-01

230

Determinants of sex hormone—binding globulin blood concentrations in premenopausal and postmenopausal women with different estrogen status  

Microsoft Academic Search

In women, sex hormone—binding globulin (SHBG) concentrations are the result of a balanced effect of stimulatory and inhibitory factors. Estrogens represent the principal stimulatory hormones, whereas androgens, insulin, excess body fat, and the pattern of body fat distribution have inhibitory effects. Menopause is characterized by major changes in blood sex steroid concentrations, notably a marked reduction of estradiol levels. In

Renato Pasquali; Valentina Vicennati; Doriana Bertazzo; Francesco Casimirri; Giancarlo Pascal; Ornella Tortelli; Antonio Maria Morselli Labate

1997-01-01

231

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

PubMed

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 ?mol/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 ?mol/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. PMID:24274457

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

2014-01-01

232

[The antiinflammatory activity of shikonin and its inhibitory effect on leukotriene B4 biosynthesis].  

PubMed

Shikonin is one of the active components isolated from the dry root of Arnebia euchroma (Royle) Johnst (AERJ). It has been shown to have anti inflammatory activity on formaldehyde induced paw swelling in rats. Preparations of AERJ has been used clinically in curing phlebitis and vascular purpura. In the present study, sc administered shikonin was shown to have significant inhibitory effects on ear edema induced by croton oil in mice and paw swelling induced by yeast in rats. In order to investigate the influence of shikonin on biosynthesis of LTB4 and 5-HETE, an in vitro leukocyte incubation system was adopted. The results showed that shikonin has fairly strong inhibitory effects on LTB4 and 5-HETE biosynthesis. Its effects and concentrations fit a positive relationship within the range of 10(-7)-10(-4) mol.L-1. The equations of inhibition (Y) versus concentration (X, LogC) obtained by linear regression were Y = 166 + 18.7X (r = 0.9319) for LTB4 and Y = 173 + 18.7X (r = 0.9856) for 5-HETE. The IC50 were 6.2 x 10(-7) and 2.6 x 10(-7) mol.L-1, respectively. The results also indicate that natural shikonin derivatives have similar inhibitory effects on LTB4 biosynthesis. These results suggest that inhibition of LTB4 and 5-HETE may play a major role in the mechanism of anti inflammatory effects of shikonin. PMID:8079645

Wang, W J; Bai, J Y; Liu, D P; Xue, L M; Zhu, X Y

1994-01-01

233

The inhibitory effect of Prunella vulgaris L. on aldose reductase and protein glycation.  

PubMed

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 IC(50) values of rAR and rhAR at 3.2 ± 0.55 ?M and 12.58 ± 0.32 ?M, 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. PMID:23091363

Li, Hong Mei; Kim, Jin Kyu; Jang, Jai Man; Kwon, Sang Oh; Cui, Cheng Bi; Lim, Soon Sung

2012-01-01

234

Screening of traditional European herbal medicines for acetylcholinesterase and butyrylcholinesterase inhibitory activity.  

PubMed

Acetylcholinesterase (AChE) inhibitors are widely used for the symptomatic treatment of Alzheimer's disease (AD) to enhance central cholinergic transmission. On the other hand, butyrylcholinesterase (BuChE) inhibitors were reported to produce a significant increase in brain extracellular AChE without triggering severe peripheral or central side effects. In the present study, we selected twelve plants used in traditional European medicine to treat different central nervous system (CNS) disorders or to improve memory. Methanolic and hexane extracts of these plants were tested for the AChE and BuChE inhibitory activity using Ellman's colorimetric method. The most potent AChE and BuChE inhibition was observed in the hexane extracts of the flowers of Arnica chamissonis Less. subs. foliosa and Ruta graveolens L. herb at a concentration of 400 microg mL(-1). However, methanolic extracts of the flowers of Arnica chamissonis Less. subs. foliosa and the Hypericum perforatum L. herb demonstrated at the same concentration, selective inhibition only against AChE but not against BuChE. The other extracts did not show any significant AChE or BuChE inhibitory activity. Our results show that further investigations of the extracts of arnica, rue and St. John's Wort are needed to identity the compounds responsible for the AChE and BuChE inhibitory activity. PMID:20228046

Wszelaki, Natalia; Kuciun, Agnieszka; Kiss, Anna Karolina

2010-03-01

235

Angiotensin I converting enzyme inhibitory activities of various fermented foods.  

PubMed

Angiotensin I converting enzyme (ACE, E.C. 3.4.15.1) inhibitory activity were measured with 11 kinds (31 items) of fermented foods. Strong inhibitory activity was detected in soy sauce, fish sauce, natto, nyufu, and cheese, but not in mirin, sake, or vinegar. PMID:7613003

Okamoto, A; Hanagata, H; Matsumoto, E; Kawamura, Y; Koizumi, Y; Yanagida, F

1995-06-01

236

Individual Differences in Inhibitory Control and Children's Theory of Mind.  

ERIC Educational Resources Information Center

Examined relation between individual differences in inhibitory control (IC) and theory-of-mind (ToM) performance in preschoolers. Found that IC was strongly related to ToM, even after controlling for several important factors. Inhibitory tasks requiring a novel response in face of a conflicting prepotent response and those requiring delay of a…

Carlson, Stephanie M.; Moses, Louis J.

2001-01-01

237

Inhibitory Control Predicts Language Switching Performance in Trilingual Speech Production  

ERIC Educational Resources Information Center

This study investigated the role of domain-general inhibitory control in trilingual speech production. Taking an individual differences approach, we examined the relationship between performance on a non-linguistic measure of inhibitory control (the Simon task) and a multilingual language switching task for a group of fifty-six native English (L1)…

Linck, Jared A.; Schwieter, John W.; Sunderman, Gretchen

2012-01-01

238

Sustained Attention and Age Predict Inhibitory Control during Early Childhood  

ERIC Educational Resources Information Center

Executive functioning skills develop rapidly during early childhood. Recent research has focused on specifying this development, particularly predictors of executive functioning skills. Here we focus on sustained attention as a predictor of inhibitory control, one key executive functioning component. Although sustained attention and inhibitory

Reck, Sarah G.; Hund, Alycia M.

2011-01-01

239

Mechanism of Inhibitory Effect of Dextran Sulfate and Heparin on Replication of Human Immunodeficiency Virus in vitro  

Microsoft Academic Search

The sulfated polysaccharides dextran sulfate and heparin have proved to be potent and selective inhibitors of human immunodeficiency virus type 1 (HIV-1) in vitro. Dextran sulfate (Mr 5000) and heparin (Mr 15,000) completely protected MT-4 cells against HIV-1-induced cytopathogenicity at a concentration of 25 mu g\\/ml. Their 50% inhibitory concentrations were 9.1 mu g\\/ml (dextran sulfate) and 7.0 mu g\\/ml

Masanori Baba; Rudi Pauwels; Jan Balzarini; Jef Arnout; Jan Desmyter; Erik de Clercq

1988-01-01

240

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

USGS Publications Warehouse

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, 7?, 12?-dihydroxy-5?-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, 15?-hydroxyprogesterone (15?-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.

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

2013-01-01

241

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

PubMed

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. PMID:12236696

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

2002-09-25

242

JOURNALISM (JNLJ) MAJOR Minimum of 39 hours  

E-print Network

JOURNALISM (JNLJ) MAJOR Minimum of 39 hours Non-teaching Major Section A: Pre JRN 1000: Foundations of Journalism ........................................................ 3 Section B: Journalism Core Requirements

de Doncker, Elise

243

Gastric inhibitory polypeptide and gastric acid secretion in pregnant rats.  

PubMed

The effects of pregnancy on the basal and pentagastrin-stimulated gastric acid secretion and the level of plasma gastric inhibitory polypeptide (GIP) in rats were studied on pentobarbital-anaesthetized non-pregnant rats and rats in the 1st, 2nd, or 3rd week of gestation. Acid output was determined by titration of the gastric perfusate. Basal secretion was collected for 45 min before a 30 min infusion of pentagastrin (8 micrograms/ml/300 g body weight). Concentration of plasma GIP was measured by a radioimmunoassay (RIA). The immunoreactivity of GIP-like substance in the extract of the rat placenta collected from the rat at day 21 of gestation was examined by RIA. The biological activity of GIP-like substance in the rat placenta extract was tested by the reduction of pentagastrin-stimulated gastric acid secretion in male rats. The basal level of gastric secretion was higher in late pregnancy as compared with the non-pregnant rats. Pentagastrin induced a greater increase of gastric acid secretion in early but not late pregnant rats as compared with the non-pregnant animals. The basal and post-pentagastrin level of plasma GIP was higher in rats in late pregnancy. Both immunoreactivity and biological activity of GIP exist in the rat placenta extract. These results suggest that the normalization of gastric acid secretion in late pregnant rats is at least in part due to the production of GIP-like substance from placenta. PMID:7716131

Chen, T S; Yeh, G H; Pu, H F; Doong, M L; Lu, C C; Liu, S R; Young, T K; Ho, L T; Chang, F Y; Wang, P S

1995-01-01

244

Concentrating Information  

E-print Network

We introduce the concentrated information of tripartite quantum states. For three parties Alice, Bob and Charlie, it is defined as the maximal mutual information achievable between Alice and Charlie via local operations and classical communication performed by Charlie and Bob. The gap between classical and quantum concentrated information is shown to be an operational figure of merit for a state merging protocol involving shared mixed states and no distributed entanglement. We derive upper and lower bounds on the concentrated information, and obtain a closed expression for arbitrary pure tripartite states in the asymptotic setting. In this situation, one-way classical communication is shown to be sufficient for optimal information concentration.

Alexander Streltsov; Soojoon Lee; Gerardo Adesso

2014-10-23

245

Enzyme inhibitory constituents from Duranta repens.  

PubMed

Isoprenylated flavonoids 5,7-dihydroxy-3'-(2-hydroxy-3-methyl-3-butenyl)-3,6,4'-trimethoxyflavone (1), 3,7-dihydroxy-3'-(2-hydroxy-3-methyl-3-butenyl)-5,6,4'-trimethoxyflavone (2) and an isoprenylated acetophenone derivative (3) have been isolated from Duranta repens along with known compounds, 5-hydroxy-3,6,7,4'-tetramethoxyflavone (4), rosenonolactone (5), 6,7-dimethoxycoumarin (6), 5alpha,8alpha-epidioxyergosta-6,22-dien-3beta-ol (7) and 5alpha,8alpha-epidioxyergosta-6,9(11),22-trien-3beta-ol (8), isolated for the first time from this species. Their structures and the relative configuration were determined by spectroscopic methods (1H- and 13C-NMR, IR, UV and MS) and two-dimensional (2D)-NMR experiments. The compounds 1-5 showed inhibitory activity against prolyl endopeptidase while 4 and 5 were also active against thrombin. PMID:11964000

Anis, Itrat; Ahmed, Saeed; Malik, Abdul; Yasin, Amsha; Choudary, M Iqbal

2002-04-01

246

Melanogenesis inhibitory compounds from Saussureae Radix.  

PubMed

Ten compounds were isolated from the EtOAc soluble part of the MeOH extract of Saussureae Radix, with their effects on melanin production also evaluated in B-16 mouse melanoma cell lines stimulated with 3-isobutyl-1-methylxanthine (IBMX), an elevator of cellular cAMP. The compounds were identified as aplotaxene (1), 1 beta-hydroxy arbusculin A (2), costunolide (3), dehydrocostuslactone (4), 11 beta,13-dihydrocostunolide (5), reynosin (6), heptadec-(9Z)-enoic acid (7), beta-sitosterol (8), linoleic acid methyl ester (9) and betulinic acid methyl ester (10). Compounds 2, 9 and 10 were identified from Saussureae Radix for the first time. Furthermore, compounds 2, 3 and 6 showed potent inhibitory effects on the IBMX-induced melanogenesis, in dose-dependent manners, with IC50 values of 11, 3 and 2.5 microg/mL, respectively. As a positive control, arbutin exhibited an IC50 value of 29 microg/mL. PMID:18409040

Choi, Ji Young; Choi, Eun Hyang; Jung, Hee Wook; Oh, Joon Seok; Lee, Won-Hee; Lee, Jong Gu; Son, Jong-Keun; Kim, Youngsoo; Lee, Seung Ho

2008-03-01

247

Action potential initiation in neocortical inhibitory interneurons.  

PubMed

Action potential (AP) generation in inhibitory interneurons is critical for cortical excitation-inhibition balance and information processing. However, it remains unclear what determines AP initiation in different interneurons. We focused on two predominant interneuron types in neocortex: parvalbumin (PV)- and somatostatin (SST)-expressing neurons. Patch-clamp recording from mouse prefrontal cortical slices showed that axonal but not somatic Na+ channels exhibit different voltage-dependent properties. The minimal activation voltage of axonal channels in SST was substantially higher (?7 mV) than in PV cells, consistent with differences in AP thresholds. A more mixed distribution of high- and low-threshold channel subtypes at the axon initial segment (AIS) of SST cells may lead to these differences. Surprisingly, NaV1.2 was found accumulated at AIS of SST but not PV cells; reducing NaV1.2-mediated currents in interneurons promoted recurrent network activity. Together, our results reveal the molecular identity of axonal Na+ channels in interneurons and their contribution to AP generation and regulation of network activity. PMID:25203314

Li, Tun; Tian, Cuiping; Scalmani, Paolo; Frassoni, Carolina; Mantegazza, Massimo; Wang, Yonghong; Yang, Mingpo; Wu, Si; Shu, Yousheng

2014-09-01

248

49 CFR 387.33 - Financial responsibility, minimum levels.  

Code of Federal Regulations, 2010 CFR

...false Financial responsibility, minimum levels. 387.33 Section 387.33 Transportation...MOTOR CARRIER SAFETY REGULATIONS MINIMUM LEVELS OF FINANCIAL RESPONSIBILITY FOR MOTOR...33 Financial responsibility, minimum levels. The minimum levels of financial...

2010-10-01

249

49 CFR 387.9 - Financial responsibility, minimum levels.  

Code of Federal Regulations, 2010 CFR

...false Financial responsibility, minimum levels. 387.9 Section 387.9 Transportation...MOTOR CARRIER SAFETY REGULATIONS MINIMUM LEVELS OF FINANCIAL RESPONSIBILITY FOR MOTOR...9 Financial responsibility, minimum levels. The minimum levels of financial...

2010-10-01

250

50 CFR 648.83 - Multispecies minimum fish sizes.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Multispecies minimum fish sizes. 648.83 Section 648.83 Wildlife...Monkfish Fisheries § 648.83 Multispecies minimum fish sizes. (a) Minimum fish sizes. (1) Minimum fish sizes for...

2011-10-01

251

50 CFR 648.83 - Multispecies minimum fish sizes.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Multispecies minimum fish sizes. 648.83 Section 648.83 Wildlife...Monkfish Fisheries § 648.83 Multispecies minimum fish sizes. (a) Minimum fish sizes. (1) Minimum fish sizes for...

2010-10-01

252

50 CFR 648.83 - Multispecies minimum fish sizes.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 2012-10-01 false Multispecies minimum fish sizes. 648.83 Section 648.83 Wildlife...Monkfish Fisheries § 648.83 Multispecies minimum fish sizes. (a) Minimum fish sizes. (1) Minimum fish sizes for...

2012-10-01

253

50 CFR 648.83 - Multispecies minimum fish sizes.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 2013-10-01 false Multispecies minimum fish sizes. 648.83 Section 648.83 Wildlife...Monkfish Fisheries § 648.83 Multispecies minimum fish sizes. (a) Minimum fish sizes. (1) Minimum fish sizes for...

2013-10-01

254

Additivity and synergy between an antimicrobial peptide and inhibitory ions.  

PubMed

Recently we described the pH dependence of activity for a family of cationic antimicrobial peptides (CAMPs) selected from a combinatorial library. In the current work we report on the effects of toxic ions (Cu(2+), Zn(2+), and F(-)) and the chelator EDTA on the activity profiles of one member of this family, the 12-residue cationic antimicrobial peptide *ARVA, against a panel of microorganisms. All four ions exhibited either synergy or additivity with *ARVA for all organisms tested with the exception of *ARVA combined with NaF against Candida albicans which exhibited indifference. CuCl2 and ZnCl2 exhibited synergy with *ARVA against both the Gram negative Pseudomonas aeruginosa and the Gram positive Staphylococcus aureus as well as strong additivity against Escherichia coli at submillimolar concentrations. The chelator EDTA was synergistic with *ARVA against the two Gram negative organisms but showed only simple additivity with S. aureus and C. albicans despite their much lower MICs with EDTA. This effect may be related to the known differences in the divalent ion binding properties of the Gram negative LPS layer as compared to the peptidoglycan layer of the Gram positive organism. Unlike the other ions, NaF showed only additivity or indifference when combined with *ARVA and required much higher concentrations for activity. The yeast C. albicans did not show synergy or strong additivity with any of the inhibitory compounds tested. The effects of toxic ions and chelators observed here have important implications for applications using CAMPs and for the design of novel formulations involving CAMPs. This article is part of a Special Issue entitled: Interfacially Active Peptides and Proteins. Guest Editors: William C. Wimley and Kalina Hristova. PMID:24841756

Walkenhorst, William F; Sundrud, Justine N; Laviolette, Joshua M

2014-09-01

255

Alveolar and serum concentrations of imipenem in two lung transplant recipients supported with extracorporeal membrane oxygenation.  

PubMed

Venovenous extracorporeal membrane oxygenation (ECMO) is increasingly used in patients with respiratory failure who fail conventional treatment. Postoperative pneumonia is the most common infection after lung transplantation (40%). Imipenem is frequently used for empirical treatment of nosocomial pneumonia in the intensive care unit. Nevertheless, few data are available on the impact of ECMO on pharmacokinetics, and no data on imipenem dosing during ECMO. Currently, no guidelines exist for antibiotic dosing during ECMO support. We report the cases of 2 patients supported with venovenous ECMO for refractory acute respiratory distress syndrome following single lung transplantation for pulmonary fibrosis, treated empirically with 1 g of imipenem intravenously every 6 h. Enterobacter cloacae was isolated from the respiratory sample of Patient 1 and Klebsiella pneumoniae was isolated from the respiratory sample of Patient 2. Minimum inhibitory concentrations of the 2 isolated strains were 0.125 and 0.25 mg/L, respectively. Both patients were still alive on day 28. This is the first report, to our knowledge, of imipenem concentrations in lung transplantation patients supported with ECMO. This study confirms high variability in imipenem trough concentrations in patients on ECMO and with preserved renal function. An elevated dosing regimen (4 g/24 h) is more likely to optimize drug exposure, and therapeutic drug monitoring is recommended, where available. Population pharmacokinetic studies are indicated to develop evidence-based dosing guidelines for ECMO patients. PMID:25572932

Welsch, C; Augustin, P; Allyn, J; Massias, L; Montravers, P; Allou, N

2015-02-01

256

Synaptic basis for intense thalamocortical activation of feedforward inhibitory cells in neocortex  

E-print Network

: excitatory cells that release the neurotransmitter glutamate and inhibitory interneurons that releaseSynaptic basis for intense thalamocortical activation of feedforward inhibitory cells in neocortex to the neocortex. This input activates inhibitory interneurons more strongly than excitatory neurons, triggering

Lewis, Timothy

257

Spinal inhibitory circuits and their role in motor neuron degeneration.  

PubMed

In the spinal cord neuronal activity is controlled by the balance between excitatory and inhibitory neurotransmission, mediated mainly by the neurotransmitters glutamate and GABA/glycine, respectively. Alterations of this equilibrium have been associated with spinal motor neuron hyperexcitability and degeneration, which can be induced by excitotoxicity or by decreasing inhibitory neurotransmission. Here we review the ventral horn neuronal network and the possible involvement of inhibitory circuits in the mechanisms of degeneration of motor neurons characteristic of amyotrophic lateral sclerosis (ALS). Whereas glutamate mediated excitotoxicity seems to be an important factor, recent experimental and histopathological evidence argue in favor of a decreased activity of the inhibitory circuits controlling motor neuron excitability, mainly the recurrent inhibition exerted by Renshaw cells. A decreased Renshaw cell activity may be caused by cell loss or by a reduction of its inhibitory action secondary to a decreased excitation from cholinergic interneurons. Ultimately, inhibitory failure by either mechanism might lead to motor neuron degeneration, and this suggests inhibitory circuits and Renshaw cells as pharmacologic targets for ALS treatment. PMID:24157492

Ramírez-Jarquín, Uri Nimrod; Lazo-Gómez, Rafael; Tovar-Y-Romo, Luis B; Tapia, Ricardo

2014-07-01

258

Minimum Foundation Program: 2003-2004 Handbook  

ERIC Educational Resources Information Center

This handbook was created to provide the user with an informative reference of the various elements contained in the Louisiana Minimum Foundation Program formula. The MFP formula adopted by the State Board of Elementary and Secondary Education and approved by the Legislature determines the cost of a minimum foundation program of education in all…

Louisiana State Department of Education, 2004

2004-01-01

259

Minimum Conditions for Congruence of Quadrilaterals.  

ERIC Educational Resources Information Center

A complete characterization of minimum conditions for congruence of quadrilaterals is presented. Convex quadrilaterals are treated first, then concave quadrilaterals are considered. A study of such minimum conditions is seen to provide some interesting and important activities for students. Only background in triangle congruence is necessary. (MP)

Vance, Irvin E.

1982-01-01

260

Minimum-Perimeter Polygons of Digitized Silhouettes  

Microsoft Academic Search

The minimum-perimeter polygon of a silhouette has been shown to be a means for recognizing convex silhouettes and for smoothing the effects of digitization in silhouettes. We describe a new method of computing the minimum-perimeter polygon (MPP) of any digitized silhouette satisfying certain constraints of connectedness and smoothness, and establish the underlying theory. Such a digitized silhouette is called a

Jack Sklansky; Robert L. Chazin; Bruce J. Hansen

1972-01-01

261

Antioxidant Activities and Tyrosinase Inhibitory Effects of Different Extracts from Pleurotus ostreatus Fruiting Bodies  

PubMed Central

We evaluated the antioxidant activity and tyrosinase inhibitory effects of Pleurotus ostreatus fruiting bodies extracted with acetone, methanol, and hot water. The antioxidant activities were tested against ?-carotene-linoleic acid, reducing power, 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity, and ferrous chelating ability. Furthermore, phenolic acid and flavonoid contents were also analyzed. The methanol extract showed the strongest ?-carotene-linoleic acid inhibition as compared to the other exracts. The acetone extract (8 mg/mL) showed a significantly high reducing power of 1.54 than the other extracts. The acetone extract was more effective than other extracts for scavenging on 1,1-diphenyl-2-picrylhydrazyl radicals. The strongest chelating effect (85.66%) was obtained from the acetone extract at 1.0 mg/mL. The antioxidant activities of the extracts from the P. ostreatus fruiting bodies increased with increasing concentration. A high performance liquid chromatography analysis detected seven phenolic compounds, including gallic acid, protocatechuic acid, chlorogenic acid, naringenin, hesperetin, formononetin, and biochanin-A in an acetonitrile and 0.1 N hydrochloric acid (5 : 1) solvent extract. The total phenolic compound concentration was 188 µg/g. Tyrosinase inhibition of the acetone, methanol, and hot water P. ostreatus extracts increased with increasing concentration. The results revealed that the methanol extract had good tyrosinase inhibitory ability, whereas the acetone and hot water extracts showed moderate activity at the concentrations tested. The results suggested that P. ostreatus may have potential as a natural antioxidant. PMID:23956669

Alam, Nuhu; Yoon, Ki Nam; Lee, Kyung Rim; Shin, Pyung Gyun; Cheong, Jong Chun; Yoo, Young Bok; Shim, Ja Mi; Lee, Min Woong; Lee, U Youn

2010-01-01

262

Cyclooxygenase inhibitory natural products: current status.  

PubMed

Non-steroidal anti-inflammatory drugs (NSAIDs) are of huge therapeutic benefit in the treatment of rheumatoid arthritis and various types of inflammatory conditions. The target for these drugs is cyclooxygenase (COX), a rate-limiting enzyme involved in the conversion of arachidonic acid into inflammatory prostaglandins. COX-2 selective inhibitors are believed to have the same anti-inflammatory, anti-pyretic and analgesic activities as that of nonselective inhibitor NSAIDs with little or none of the gastrointestinal side effects. Thus, in the last 6-7 years several selective COX-2 inhibitors including coxibs were discovered and introduced into clinic. Recent reports evidence that selective COX-2 inhibitor such as rofecoxib, can lead to thrombotic cardiovascular events through inhibition of prostacyclin formation in the infracted heart. This has resulted in withdrawal of rofecoxib from the clinic in September 2004. Moreover, the COX-2/COX-1 selectivity ratio is vital in the design of COX-2 inhibitory drugs, as it is clear from rofecoxib, which is more than 50-fold COX-2 selective. After looking at all above mentioned facts, natural product-based compounds seem better as these compounds are generally supposed to be devoid of severe side effects. The literature indicates that natural product-based compounds are mainly COX-1 selective. Through minor semi-synthetic changes in the structures, their selectivity towards COX-2 can be increased. The present review article addresses natural product COX inhibitors of plant and marine origin, reported during last ten years and their advantages, possible leads for further development and current status. In addition we describe our experience in the characterization, design and synthesis of potential natural COX inhibitors. PMID:16529558

Jachak, Sanjay M

2006-01-01

263

Butyrylcholinesterase inhibitory guaianolides from Amberboa ramosa.  

PubMed

Phytochemical investigation of the whole plant of Amberboa ramosa led to the isolation of six sesquiterpene lactones which could be identified as 8alpha-hydroxy-11beta-methyl-1alphaH, 5alphaH, 6betaH, 7alphaH, 11alphaH-guai-10(14), 4(15)-dien-6, 12-olide(1), 3beta, 8alpha-dihydroxy-11alpha-methyl-1alphaH, 5alphaH, 6betaH, 7alphaH, 11betaH-guai-10(14), 4 (15)-dien-6, 12-olide (2), 3beta, 4alpha, 8alpha-trihydroxy-4beta-(hydroxymethyl)-1alphaH, 5alphaH, 6betaH, 7alphaH-guai-10(14), 11(13)-dien-6, 12-olide (3), 3beta, 4alpha, 8alpha-trihydroxy-4beta-(chloromethyl)-1alphaH, 5alphaH, 6betaH, 7alphaH-guai-10(14),11(13)-dien-6, 12-olide(4), 3beta, 4alpha, dihydroxy-4beta-(hydroxymethyl)-1alphaH, 5alphaH, 6betaH, 7alphaH-guai-10(14),11(13)-dien-6, 12-olide(5), 3beta, 4alpha-dihydroxy-4beta-(chloromethyl)-8alpha-(4-hydroxymethacrylate)-1alphaH, 5alphaH, 6betaH, 7alphaH-guai-10(14),11 (13)-dien-6,12-olide (6) by spectroscopic methods. All of them showed inhibitory potential against butyrylcholinesterase. PMID:15789746

Khan, Sher Bahadar; Azhar-ul-Haq; Perveen, Shagufta; Afza, Nighat; Malik, Abdul; Nawaz, Sarfraz Ahmad; Shah, Muhammad Raza; Choudhary, Muhammad Iqbal

2005-02-01

264

Evaluation of 5?-reductase inhibitory activity of certain herbs useful as antiandrogens.  

PubMed

This study demonstrates 5?-reductase inhibitory activity of certain herbs useful in the management of androgenic disorders. Ganoderma lucidum (Curtis) P. Karst (GL), Urtica dioica Linn. (UD), Caesalpinia bonducella Fleming. (CB), Tribulus terrestris Linn. (TT), Pedalium murex Linn. (PM), Sphaeranthus indicus Linn. (SI), Cuscuta reflexa Roxb. (CR), Citrullus colocynthis Schrad. (CC), Benincasa hispida Cogn. (BH), Phyllanthus niruri Linn. (PN) and Echinops echinatus Linn. (EE) were included in the study. Petroleum ether, ethanol and aqueous extracts of these herbs were tested for their 5?-reductase inhibitory activity against the standard 5?-reductase inhibitor, finasteride. A biochemical method to determine the activity of 5?-reductase was used to evaluate the inhibition of different extracts to the enzyme. The optical density (OD) value of each sample was measured continuously with ultraviolet spectrophotometer for the reason that the substrate NADPH has a specific absorbance at 340 nm. As the enzyme 5?-reductase uses NADPH as a substrate, so in the presence of 5?-reductase inhibitor, the NADPH concentration will increase with the function of time. This method thus implicates the activity of 5?-reductase. The method proved to be extremely useful to screen the herbs for their 5?-reductase inhibitory potential. GL, UD, BH, SI and CR came out to be promising candidates for further exploring their antiandrogenic properties. PMID:23710567

Nahata, A; Dixit, V K

2014-08-01

265

Cellular target recognition of perfluoroalkyl acids: in vitro evaluation of inhibitory effects on lysine decarboxylase.  

PubMed

Perfluoroalkyl acids (PFAAs) have been shown to bind with hepatic peroxisome proliferator receptor ?, estrogen receptors and human serum albumin and subsequently cause some toxic effects. Lysine decarboxylase (LDC) plays an important role in cell growth and developmental processes. In this study, the inhibitory effect of 16 PFAAs, including 13 perfluorinated carboxylic acids (PFCAs) and 3 perfluorinated sulfonic acids (PFSAs), on lysine decarboxylase (LDC) activity was investigated. The inhibition constants obtained in fluorescence enzyme assays fall in the range of 2.960 ?M to 290.8 ?M for targeted PFCAs, and 41.22 ?M to 67.44 ?M for targeted PFSAs. The inhibitory effect of PFCAs increased significantly with carbon chain (7-18 carbons), whereas the short chain PFCAs (less than 7 carbons) did not show any effect. Circular dichroism results showed that PFAA binding induced significant protein secondary structural changes. Molecular docking revealed that the inhibitory effect could be rationalized well by the cleft binding mode as well as the size, substituent group and hydrophobic characteristics of the PFAAs. At non-cytotoxic concentrations, three selected PFAAs inhibited LDC activity in HepG2 cells, and subsequently resulted in the decreased cadaverine level in the exposed cells, suggesting that LDC may be a possible target of PFAAs for their in vivo toxic effects. PMID:25093300

Wang, Sufang; Lv, Qiyan; Yang, Yu; Guo, Liang-Hong; Wan, Bin; Zhao, Lixia

2014-10-15

266

Kappa Opioid Receptor Activation Decreases Inhibitory Transmission and Antagonizes Alcohol Effects in Rat Central Amygdala  

PubMed Central

Activation of the kappa opioid receptor (KOR) system mediates negative emotional states and considerable evidence suggests that KOR and their natural ligand, dynorphin, are involved in ethanol dependence and reward. The central amygdala (CeA) plays a major role in alcohol dependence and reinforcement. Dynorphin peptide and gene expression are activated in the amygdala during acute and chronic administration of alcohol, but the effects of activation or blockade of KOR on inhibitory transmission and ethanol effects have not been studied. We used the slice preparation to investigate the physiological role of KOR and interaction with ethanol on GABAA receptor-mediated synaptic transmission. Superfusion of dynorphin or U69593 onto CeA neurons decreased evoked inhibitory postsynaptic potentials (IPSPs) in a concentration-dependent manner, an effect prevented by the KOR antagonist norbinaltorphimine (norBNI). Applied alone, norBNI increased GABAergic transmission, revealing a tonic endogenous activity at KOR. Paired-pulse analysis suggested a presynaptic KOR mechanism. Superfusion of ethanol increased IPSPs and pretreatment with KOR agonists diminished the ethanol effect. Surprisingly, the ethanol-induced augmentation of IPSPs was completely obliterated by KOR blockade. Our results reveal an important role of the dynorphin/KOR system in the regulation of inhibitory transmission and mediation of ethanol effects in the CeA. PMID:24157490

Gilpin, Nicholas W.; Roberto, Marisa; Koob, George F.; Schweitzer, Paul

2013-01-01

267

Microbial oceanography of anoxic oxygen minimum zones  

PubMed Central

Vast expanses of oxygen-deficient and nitrite-rich water define the major oxygen minimum zones (OMZs) of the global ocean. They support diverse microbial communities that influence the nitrogen economy of the oceans, contributing to major losses of fixed nitrogen as dinitrogen (N2) and nitrous oxide (N2O) gases. Anaerobic microbial processes, including the two pathways of N2 production, denitrification and anaerobic ammonium oxidation, are oxygen-sensitive, with some occurring only under strictly anoxic conditions. The detection limit of the usual method (Winkler titrations) for measuring dissolved oxygen in seawater, however, is much too high to distinguish low oxygen conditions from true anoxia. However, new analytical technologies are revealing vanishingly low oxygen concentrations in nitrite-rich OMZs, indicating that these OMZs are essentially anoxic marine zones (AMZs). Autonomous monitoring platforms also reveal previously unrecognized episodic intrusions of oxygen into the AMZ core, which could periodically support aerobic metabolisms in a typically anoxic environment. Although nitrogen cycling is considered to dominate the microbial ecology and biogeochemistry of AMZs, recent environmental genomics and geochemical studies show the presence of other relevant processes, particularly those associated with the sulfur and carbon cycles. AMZs correspond to an intermediate state between two “end points” represented by fully oxic systems and fully sulfidic systems. Modern and ancient AMZs and sulfidic basins are chemically and functionally related. Global change is affecting the magnitude of biogeochemical fluxes and ocean chemical inventories, leading to shifts in AMZ chemistry and biology that are likely to continue well into the future. PMID:22967509

Ulloa, Osvaldo; Canfield, Donald E.; DeLong, Edward F.; Letelier, Ricardo M.; Stewart, Frank J.

2012-01-01

268

Concentrating Radioactivity  

ERIC Educational Resources Information Center

By concentrating radioactivity contained on luminous dials, a teacher can make a high reading source for classroom experiments on radiation. The preparation of the source and its uses are described. (DT)

Herrmann, Richard A.

1974-01-01

269

Inhibitory signaling through signal regulatory protein-is not sufficient  

E-print Network

roles in hemostasis, cardiovascular pathophysiology, ischemic injuries, inflammation, radiation injuries, and cancer. Correspondingly, antibodies that block thrombospondin-1 or SIRP binding and antisense, contradicting evidence to the contrary by Willingham. Furthermore, if blocking inhibitory signaling through SIRP

Frazier, William A.

270

Expression of macrophage migration inhibitory factor in human glomerulonephritis  

Microsoft Academic Search

Expression of macrophage migration inhibitory factor in human glomerulonephritis.BackgroundWe have recently demonstrated that macrophage migration inhibitory factor (MIF) plays a pathogenic role in experimental glomerulonephritis (GN). The aim of the current study was to investigate MIF expression in human GN.MethodsMIF expression was examined by in situ hybridization and immunohistochemistry staining in 65 biopsies from a variety of glomerulonephridities.ResultsThere is constitutive

Hui Y Lan; Niansheng Yang; David J Nikolic-Paterson; Xue Q Yu; Wei Mu; Nicole M Isbel; Christine N Metz; Richard Bucala; Robert C Atkins

2000-01-01

271

Alcoholic fermentation: on the inhibitory effect of ethanol  

Microsoft Academic Search

The inhibitory effect of ethanol was studied during alcoholic fermentation under strictly anaerobic conditions assured by stripping dissolved oxygen with pure nitrogen. It is shown that ehthanol produced during batch fermentation is more inhibitory than added ethanol in the range of 0 to 76 g\\/liter. Thus, the inhibition constant is 105.2 and 3.8 g\\/liter for added and produced ethanol, respectively.

M. Novak; P. Strehaiano; M. Moreno; G. Goma

1981-01-01

272

Testable scenario for relativity with minimum length  

NASA Astrophysics Data System (ADS)

I propose a general class of spacetimes whose structure is governed by observer-independent scales of both velocity (/c) and length (Planck length), and I observe that these spacetimes can naturally host a modification of FitzGerald-Lorentz contraction such that lengths which in their inertial rest frame are bigger than a ``minimum length'' are also bigger than the minimum length in all other inertial frames. With an analysis in leading order in the minimum length, I show that this is the case in a specific illustrative example of postulates for relativity with velocity and length observer-independent scales.

Amelino-Camelia, G.

2001-06-01

273

Isolation, Purification and Molecular Mechanism of a Peanut Protein-Derived ACE-Inhibitory Peptide  

PubMed Central

Although a number of bioactive peptides are capable of angiotensin I-converting enzyme (ACE) inhibitory effects, little is known regarding the mechanism of peanut peptides using molecular simulation. The aim of this study was to obtain ACE inhibiting peptide from peanut protein and provide insight on the molecular mechanism of its ACE inhibiting action. Peanut peptides having ACE inhibitory activity were isolated through enzymatic hydrolysis and ultrafiltration. Further chromatographic fractionation was conducted to isolate a more potent peanut peptide and its antihypertensive activity was analyzed through in vitro ACE inhibitory tests and in vivo animal experiments. MALDI-TOF/TOF-MS was used to identify its amino acid sequence. Mechanism of ACE inhibition of P8 was analyzed using molecular docking and molecular dynamics simulation. A peanut peptide (P8) having Lys-Leu-Tyr-Met-Arg-Pro amino acid sequence was obtained which had the highest ACE inhibiting activity of 85.77% (half maximal inhibitory concentration (IC50): 0.0052 mg/ml). This peanut peptide is a competitive inhibitor and show significant short term (12 h) and long term (28 days) antihypertensive activity. Dynamic tests illustrated that P8 can be successfully docked into the active pocket of ACE and can be combined with several amino acid residues. Hydrogen bond, electrostatic bond and Pi-bond were found to be the three main interaction contributing to the structural stability of ACE-peptide complex. In addition, zinc atom could form metal-carboxylic coordination bond with Tyr, Met residues of P8, resulting into its high ACE inhibiting activity. Our finding indicated that the peanut peptide (P8) having a Lys-Leu-Tyr-Met-Arg-Pro amino acid sequence can be a promising candidate for functional foods and prescription drug aimed at control of hypertension. PMID:25347076

Shi, Aimin; Liu, Hongzhi; Liu, Li; Hu, Hui; Wang, Qiang; Adhikari, Benu

2014-01-01

274

Enhanced inhibitory neurotransmission in the cerebellar cortex of Atp1a3-deficient heterozygous mice  

PubMed Central

Dystonia is characterized by excessive involuntary and prolonged simultaneous contractions of both agonist and antagonist muscles. Although the basal ganglia have long been proposed as the primary region, recent studies indicated that the cerebellum also plays a key role in the expression of dystonia. One hereditary form of dystonia, rapid-onset dystonia with parkinsonism (RDP), is caused by loss of function mutations of the gene for the Na pump ?3 subunit (ATP1A3). Little information is available on the affected brain regions and mechanism for dystonia by the mutations in RDP. The Na pump is composed of ? and ? subunits and maintains ionic gradients of Na+ and K+ across the cell membrane. The gradients are utilized for neurotransmitter reuptake and their alteration modulates neural excitability. To provide insight into the molecular aetiology of RDP, we generated and analysed knockout heterozygous mice (Atp1a3+/?). Atp1a3+/? showed increased symptoms of dystonia that is induced by kainate injection into the cerebellar vermis. Atp1a3 mRNA was highly expressed in Purkinje cells and molecular-layer interneurons, and its product was concentrated at Purkinje cell soma, the site of abundant vesicular ?-aminobutyric acid transporter (VGAT) signal, suggesting the presynaptic localization of the ?3 subunit in the inhibitory synapse. Electrophysiological studies showed that the inhibitory neurotransmission at molecular-layer interneuron–Purkinje cell synapses was enhanced in Atp1a3+/? cerebellar cortex, and that the enhancement originated via a presynaptic mechanism. Our results shed light on the role of Atp1a3 in the inhibitory synapse, and potential involvement of inhibitory synaptic dysfunction for the pathophysiology of dystonia. PMID:23652595

Ikeda, Keiko; Satake, Shin'Ichiro; Onaka, Tatsushi; Sugimoto, Hiroki; Takeda, Naoki; Imoto, Keiji; Kawakami, Kiyoshi

2013-01-01

275

Lactoferrin Inhibits Porphyromonas gingivalis Proteinases and Has Sustained Biofilm Inhibitory Activity  

PubMed Central

Porphyromonas gingivalis is a bacterial pathogen associated with chronic periodontitis that results in destruction of the tooth's supporting tissues. The major virulence determinants of P. gingivalis are its cell surface Arg- and Lys-specific cysteine proteinases, RgpA/B and Kgp. Lactoferrin (LF), an 80-kDa iron-binding glycoprotein found in saliva and gingival crevicular fluid, is believed to play an important role in innate immunity. In this study, bovine milk LF displayed proteinase inhibitory activity against P. gingivalis whole cells, significantly inhibiting both Arg- and Lys-specific proteolytic activities. LF inhibited the Arg-specific activity of purified RgpB, which lacks adhesin domains, and also inhibited the same activity of the RgpA/Kgp proteinase-adhesin complexes in a time-dependent manner, with a first-order inactivation rate constant (kinact) of 0.023 min?1 and an inhibitor affinity constant (KI) of 5.02 ?M. LF inhibited P. gingivalis biofilm formation by >80% at concentrations above 0.625 ?M. LF was relatively resistant to hydrolysis by P. gingivalis cells but was cleaved into two major polypeptides (53 and 33 kDa) at R284 to S285, as determined by in-source decay mass spectrometry; however, these polypeptides remained associated with each other and retained inhibitory activity. The biofilm inhibitory activity of LF against P. gingivalis was not attributed to direct antibacterial activity, as LF displayed little growth inhibitory activity against planktonic cells. As the known RgpA/B and Kgp inhibitor N-?-p-tosyl-l-lysine chloromethylketone also inhibited P. gingivalis biofilm formation, the antibiofilm effect of LF may at least in part be attributable to its antiproteinase activity. PMID:22214780

Dashper, Stuart G.; Pan, Yu; Veith, Paul D.; Chen, Yu-Yen; Toh, Elena C. Y.; Liu, Sze Wei; Cross, Keith J.

2012-01-01

276

Cutaneous excitatory and inhibitory input to neurones of the postsynaptic dorsal column system in the cat.  

PubMed Central

1. In chloralose-anaesthetized cats single-unit microelectrode recordings were made from axons in the dorsal columns, at the lumbar level, identified as belonging to the postsynaptic dorsal column (PSDC) system. 2. Excitatory and inhibitory receptive field arrangements of a sample of seventy-five PSDC neurones were examined in detail using natural cutaneous stimuli. 3. The sample was characterized by a high degree of convergent input: 80% of units were activated by both light tactile and noxious mechanical stimuli and more than half of those examined were excited by noxious radiant heat. In addition, three-quarters of the units had inhibitory receptive fields on the ipsilateral limb. 4. Twenty-three units (27%) were influenced by input from areas of both hairy and glabrous skin covering the foot and distal limb. Neurones in this group had complex receptive fields, many of which occupied several discontinuous areas of skin. Background and evoked activity of these units could frequently be inhibited by light tactile and/or noxious stimuli. Their inhibitory receptive fields occupied small areas of skin overlapping or adjacent to excitatory fields. 5. Fifty-two units (73%) had receptive fields restricted to areas of hairy skin on the thigh and upper hindlimb. Half the units in this group had coextensive low- and high-threshold excitatory areas but about one-third had a concentric receptive field organization; a high-threshold excitatory component extending beyond, or around, a central low-threshold area. The discharge of these units could be inhibited only by light tactile stimuli. Their inhibitory receptive fields covered extensive areas of skin, sometimes completely surrounding the excitatory field. 6. The complex receptive field arrangements observed for neurones of the postsynaptic dorsal column system are discussed in relation to previous observations on dorsal horn neurones of other ascending tracts. PMID:3411503

Noble, R; Riddell, J S

1988-01-01

277

The neural networks of inhibitory control in posttraumatic stress disorder  

PubMed Central

Objective Posttraumatic stress disorder (PTSD) involves deficits in information processing that may reflect hypervigilence and deficient inhibitory control. To date, however, no PTSD neuroimaging study has directly examined PTSD-related changes in executive inhibition. Our objective was to investigate the hypothesis that executive inhibitory control networks are compromised in PTSD. Methods Functional magnetic resonance imaging (fMRI) was used during a Go/No-Go inhibition task completed by a sample of patients with PTSD (n = 23), a matched sample of healthy (i.e. without trauma exposure) control participants (n = 23) and a sample of control participants with trauma exposure who did not meet criteria for PTSD (n = 17). Results Participants with PTSD showed more inhibition-related errors than did individuals without trauma exposure. During inhibition, control participants activated a right-lateralized cortical inhibitory network, whereas patients with PTSD activated only the left lateral frontal cortex. PTSD was associated with a reduction in right cortical activation and increased activation of striatal and somatosensory regions. Conclusion The increased inhibitory error and reduced right frontal cortical activation are consistent with compromised inhibitory control in PTSD, while the increased activation of brain regions associated with sensory processing and a greater demand on inhibitory control may reflect enhanced stimulus processing in PTSD, which may undermine cortical control mechanisms. PMID:18787658

Falconer, Erin; Bryant, Richard; Felmingham, Kim L.; Kemp, Andrew H.; Gordon, Evian; Peduto, Anthony; Olivieri, Gloria; Williams, Leanne M.

2008-01-01

278

A chiral ligand exchange CE system for monitoring inhibitory effect of kojic acid on tyrosinase.  

PubMed

A facile chiral ligand exchange capillary electrophoresis (CLE-CE) system with Zn(II)-L-alanine as the chiral selector in the presence of ?-cyclodextrin has been developed for enantioseparation of dansyl amino acids. The influence of the key factors, such as buffer pH, the ratio of Zn (II) to ligand, the concentration of ?-cyclodextrin and the concentration of the complex, were investigated in detail when D, L-Tyr and D, L-Thr were selected as the model analytes. The proposed method showed favorable quantitative analysis property of dansyl D, L-tyrosine with good linearity (r(2)?0.999) and reproducibility (RSD?3.8%), then, it was applied in studying the activity of tyrosinase through the determination of L-tyrosine concentration variation after being incubated with the enzyme. Further, the inhibitory efficiency of kojic acid and soy sauce on the tyrosinase was investigated. The IC50 of kojic acid obtained from the sigmoidal inhibitory curve was 21.35 ?M. The results imply that the proposed CLE-CE system has the potential in exploring the activity of enzyme and screening the inhibitors of enzyme. PMID:24148524

Sun, Bing-bing; Qi, Li; Mu, Xiao-yu; Qiao, Juan; Wang, Ming-lin

2013-11-15

279

Inhibitory effects of spices on growth and toxin production of toxigenic fungi.  

PubMed

The inhibitory effects of 29 commercial powdered spices on the growth and toxin production of three species of toxigenic Aspergillus were observed by introducing these materials into culture media for mycotoxin production. Of the 29 samples tested, cloves, star anise seeds, and allspice completely inhibited the fungal growth, whereas most of the others inhibited only the toxin production. Eugenol extracted from cloves and thymol from thyme caused complete inhibition of the growth of both Aspergillus flavus and Aspergillus versicolor at 0.4 mg/ml or less. At a concentration of 2 mg/ml, anethol extracted from star anise seeds inhibited the growth of all the strains. PMID:6769391

Hitokoto, H; Morozumi, S; Wauke, T; Sakai, S; Kurata, H

1980-04-01

280

Inhibitory effects of spices on growth and toxin production of toxigenic fungi.  

PubMed Central

The inhibitory effects of 29 commercial powdered spices on the growth and toxin production of three species of toxigenic Aspergillus were observed by introducing these materials into culture media for mycotoxin production. Of the 29 samples tested, cloves, star anise seeds, and allspice completely inhibited the fungal growth, whereas most of the others inhibited only the toxin production. Eugenol extracted from cloves and thymol from thyme caused complete inhibition of the growth of both Aspergillus flavus and Aspergillus versicolor at 0.4 mg/ml or less. At a concentration of 2 mg/ml, anethol extracted from star anise seeds inhibited the growth of all the strains. PMID:6769391

Hitokoto, H; Morozumi, S; Wauke, T; Sakai, S; Kurata, H

1980-01-01

281

Effect of Different Commerical Agar Preparations on the Inhibitory Activities of Phenols  

PubMed Central

The minimal inhibitory concentrations of 11 phenolic inhibitors were compared in five commercial agars and in nutrient broth. It was found that the brand of agar affected the end point obtained for a particular inhibitor, and that the degree of antagonism varied with each compound studied. The results indicate that there are at least two deleterious factors present in agar, one of which is water-soluble and one which is not. The major portion of the total antagonism was due to the water-soluble factor, which could be removed by washing the agar in warm distilled water prior to use in the test medium. PMID:5959856

Sands, J. G.; Bennett, E. O.

1966-01-01

282

MOTIVATION AND CONCENTRATION WORKSHOP CONCENTRATION  

E-print Network

's hard for me to take notes and listen at the same time. Others: Possible causes for poor concentration, sleeping, and exercise patterns, depression, anxiety, chronic pain or other related health and mental

283

Evaluation of antioxidant and xanthine oxidase inhibitory activity of different solvent extracts of leaves of Citrullus colocynthis  

PubMed Central

Background: Citrullus colocynthis is a folk medicinal plan of United Arab Emirates. Several studies on this plant reported and focused on the biological and toxicological profile of fruits pulp. The present study focused on the antioxidant potency of leaf extract of this plant. Aim: To evaluate the antioxidant and xanthine oxidase (XO) inhibitory activities of C. colocynthis by chemical method. Materials and Methods: Four different solvent extracts (methanol-CCM, methanol: water (1:1)-CCMW, chloroform-CCC and hexane-CCH) of leaves of C. colocynthis were investigated for their free radical scavenging activity using DPPH radical as a substrate, lipid peroxidation (LPO) inhibitory activity using a model system consisting of ?-carotene-linoleic acid, superoxide radical scavenging activity (enzymatically/nonenzymatically) and XO inhibitory activity. A dose response curve was plotted for determining SC50 and IC50 values for expressing the results of free radical scavenging activity and XO inhibitory activities respectively. Results: The high polyphenolic content of CCM and CCMW extract showed highest antioxidant activity irrespective the method used for this investigation. The overall results decreased in the order of: CCM > CCMW > CCC > CCH. CCH extract was inactive towards chemically generated superoxide radical and poor DPPH radical scavengers. The results of LPO inhibitory activities of leaves extract (0.1, 0.5 and 1.0 mg/mL) also decreased in the order of: CCM > CCMW > CCC > CCH. Overall 1.0 mg/mL leaves extract showed highest antioxidant potency amongst the studied concentration. Conclusion: CCMW and CCM extract of C. colocynthis exhibited promising antioxidants and XO inhibitory activities. PMID:25002802

Nessa, Fazilatun; Khan, Saeed A.

2014-01-01

284

Fall 2013 PAINTING AND DRAWING CONCENTRATION PORTFOLIO REVIEW  

E-print Network

Fall 2013 PAINTING AND DRAWING CONCENTRATION PORTFOLIO REVIEW WEDNESDAY, OCTOBER 2 To be eligible for the drawing or painting concentration you must have completed the minimum: Studio Foundation First year program and Drawing concentration: completed ARST 2000 or ARST 2010 Painting concentration: ARST 2100

Arnold, Jonathan

285

Microbial oceanography of anoxic oxygen minimum zones  

E-print Network

Vast expanses of oxygen-deficient and nitrite-rich water define the major oxygen minimum zones (OMZs) of the global ocean. They support diverse microbial communities that influence the nitrogen economy of the oceans, ...

Ulloa, Osvaldo

286

7 CFR 929.101 - Minimum exemption.  

Code of Federal Regulations, 2010 CFR

...IN STATES OF MASSACHUSETTS, RHODE ISLAND, CONNECTICUT, NEW JERSEY, WISCONSIN, MICHIGAN, MINNESOTA, OREGON, WASHINGTON, AND LONG ISLAND IN THE STATE OF NEW YORK Rules and Regulations § 929.101 Minimum...

2010-01-01

287

7 CFR 929.101 - Minimum exemption.  

...IN STATES OF MASSACHUSETTS, RHODE ISLAND, CONNECTICUT, NEW JERSEY, WISCONSIN, MICHIGAN, MINNESOTA, OREGON, WASHINGTON, AND LONG ISLAND IN THE STATE OF NEW YORK Rules and Regulations § 929.101 Minimum...

2014-01-01

288

7 CFR 929.101 - Minimum exemption.  

Code of Federal Regulations, 2011 CFR

...IN STATES OF MASSACHUSETTS, RHODE ISLAND, CONNECTICUT, NEW JERSEY, WISCONSIN, MICHIGAN, MINNESOTA, OREGON, WASHINGTON, AND LONG ISLAND IN THE STATE OF NEW YORK Rules and Regulations § 929.101 Minimum...

2011-01-01

289

7 CFR 929.101 - Minimum exemption.  

Code of Federal Regulations, 2013 CFR

...IN STATES OF MASSACHUSETTS, RHODE ISLAND, CONNECTICUT, NEW JERSEY, WISCONSIN, MICHIGAN, MINNESOTA, OREGON, WASHINGTON, AND LONG ISLAND IN THE STATE OF NEW YORK Rules and Regulations § 929.101 Minimum...

2013-01-01

290

30 CFR 202.352 - Minimum royalty.  

Code of Federal Regulations, 2010 CFR

... Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR MINERALS REVENUE MANAGEMENT ROYALTIES Geothermal Resources § 202.352 Minimum royalty. In no event shall the lessee's annual royalty payments for any producing...

2010-07-01

291

7 CFR 4280.136 - Minimum retention.  

Code of Federal Regulations, 2010 CFR

...BUSINESS-COOPERATIVE SERVICE AND RURAL UTILITIES SERVICE, DEPARTMENT OF AGRICULTURE LOANS AND GRANTS Renewable Energy Systems and Energy Efficiency Improvements Program Section B. Guaranteed Loans § 4280.136 Minimum retention....

2010-01-01

292

How unprecedented a solar minimum was it?  

PubMed Central

The end of the last solar cycle was at least 3 years late, and to date, the new solar cycle has seen mainly weaker activity since the onset of the rising phase toward the new solar maximum. The newspapers now even report when auroras are seen in Norway. This paper is an update of our review paper written during the deepest part of the last solar minimum [1]. We update the records of solar activity and its consequent effects on the interplanetary fields and solar wind density. The arrival of solar minimum allows us to use two techniques that predict sunspot maximum from readings obtained at solar minimum. It is clear that the Sun is still behaving strangely compared to the last few solar minima even though we are well beyond the minimum phase of the cycle 23–24 transition.

Russell, C.T.; Jian, L.K.; Luhmann, J.G.

2012-01-01

293

7 CFR 966.53 - Minimum quantities.  

Code of Federal Regulations, 2011 CFR

... AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Regulation § 966.53 Minimum quantities. The committee, with the...

2011-01-01

294

7 CFR 966.53 - Minimum quantities.  

... AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE TOMATOES GROWN IN FLORIDA Order Regulating Handling Regulation § 966.53 Minimum quantities. The committee, with the...

2014-01-01

295

On the Minimum Induced Drag of Wings  

NASA Technical Reports Server (NTRS)

This viewgraph presentation reviews the minimum induced drag of wings. The topics include: 1) The History of Spanload Development of the optimum spanload Winglets and their implications; 2) Horten Sailplanes; and 3) Flight Mechanics & Adverse yaw.

Bowers, Albion H.

2007-01-01

296

Degree-bounded minimum spanning trees  

Microsoft Academic Search

Given n points in the Euclidean plane, the degree-? minimum spanning tree (MST) problem asks for a spanning tree of minimum weight in which the degree of each vertex is at most ?. The problem is NP-hard for 2???3, while the NP-hardness of the problem is open for ?=4. The problem is polynomial-time solvable when ?=5. By presenting an improved

Raja Jothi; Balaji Raghavachari

2009-01-01

297

Maximum, Minimum, and Current Temperature Protocol  

NSDL National Science Digital Library

The purpose of this activity is to measure air (and optionally soil) temperature within one hour of solar noon and the maximum and minimum air temperatures for the previous 24 hours. Intended outcomes are that students will learn to read minimum, maximum, and current temperatures using a U-shaped thermometer, understand diurnal and annual temperature variations, and recognize factors that influence atmospheric temperatures. Supporting background materials for both student and teacher are included.

The GLOBE Program, UCAR (University Corporation for Atmospheric Research)

2003-08-01

298

Approximating Minimum Manhattan Networks in Higher Dimensions  

Microsoft Academic Search

We consider the minimum Manhattan network problem, which is defined as follows. Given a set of points called \\\\emph{terminals} in $\\\\mathbb{R}^d$, find a minimum-length network such that each pair of terminals is connected by a set of axis-parallel line segments whose total length is equal to the pair's Manhattan (that is, $L_1$-) distance. The problem is NP-hard in 2D and

Aparna Das; Emden R. Gansner; Michael Kaufmann; Stephen Kobourov; Joachim Spoerhase; Alexander Wolff

2011-01-01

299

Decorrelation of Neural-Network Activity by Inhibitory Feedback  

PubMed Central

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 excitatory (E) and inhibitory (I) neurons, but a consequence of a particular structure of correlations among the three possible pairings (EE, EI, II). PMID:23133368

Einevoll, Gaute T.; Diesmann, Markus

2012-01-01

300

Rapid Suppression of Inhibitory Synaptic Transmission by Retinoic Acid  

PubMed Central

In brain, properly balanced synaptic excitation and inhibition is critically important for network stability and efficient information processing. Here, we show that retinoic acid (RA), a synaptic signaling molecule whose synthesis is activated by reduced neural activity, induces rapid internalization of synaptic GABAA receptors in mouse hippocampal neurons, leading to significant reduction of inhibitory synaptic transmission. Similar to its action at excitatory synapses, action of RA at inhibitory synapses requires protein translation and is mediated by a nontranscriptional function of the RA-receptor RAR?. Different from RA action at excitatory synapses, however, RA at inhibitory synapses causes a loss instead of the gain of a synaptic protein (i.e., GABAARs). Moreover, the removal of GABAARs from the synapses and the reduction of synaptic inhibition do not require the execution of RA's action at excitatory synapses (i.e., downscaling of synaptic inhibition is intact when upscaling of synaptic excitation is blocked). Thus, the action of RA at inhibitory and excitatory synapses diverges significantly after the step of RAR?-mediated protein synthesis, and the regulations of GABAAR and AMPAR trafficking are independent processes. When both excitatory and inhibitory synapses are examined together in the same neuron, the synaptic excitation/inhibition ratio is significantly enhanced by RA. Importantly, RA-mediated downscaling of synaptic inhibition is completely absent in Fmr1 knock-out neurons. Thus, RA acts as a central organizer for coordinated homeostatic plasticity in both excitatory and inhibitory synapses, and impairment of this overall process alters the excitatory/inhibitory balance of a circuit and likely represents a major feature of fragile X-syndrome. PMID:23843516

Sarti, Federica; Zhang, Zhenjie; Schroeder, Jessica

2013-01-01

301

Inhibitory effects of edible marine algae extracts on degranulation of RBL-2H3 cells and mouse eosinophils  

Microsoft Academic Search

Inhibitory effects on degranulation of rat basophilic leukemia (RBL-2H3) cells and mouse eosinophils by marine algae extracts\\u000a were examined. More than 50% of the degranulation of RBL-2H3 cells was inhibited by water extracts of Ecklonia cava and Chrysymenia wrightii at a concentration of 100 ?g\\/mL. More than 50% of the degranulation of RBL-2H3 cells was inhibited by methanol extracts of

Takashi Kimiya; Kazuhiro Ohtani; Setsuko Satoh; Yuko Abe; Yoshihiko Ogita; Hirohisa Kawakita; Hideyuki Hamada; Yuko Konishi; Satoshi Kubota; Akira Tominaga

2008-01-01

302

The inhibitory effects of 5-hydroxytryptamine on gastric acid secretion by the rat isolated stomach.  

PubMed Central

1 The effect of 5-hydroxytryptamine (5-HT) on acid secretion by a rat isolated stomach preparation has been studied. 2 5-HT at 10(-5)M in the serosal bathing fluid produced significant inhibition of the acid secretory responses to histamine, pentagastrin and isoprenaline but was without effect on basal secretion or that due to bethanechol, dibutryl cyclic adenosine 3',5'-monophosphate (db cyclic AMP) or phosphodiesterase inhibition with ICI63197. Increasing the concentration of 5-HT to 5 x 10(-5) M did not change this pattern of response whilst 5-HT at 10(-6) M did not cause consistent inhibition. 3 The inhibitory action of 5-HT could be prevented by the antagonist methysergide (2.5 x 10(-5) M). This concentration of methysergide alone did not affect responses to secretagogues or basal acid output. 4 Neither propranolol (2.5 x 10(-5) M) nor tetrodotoxin (10(-6) M) antagonized the inhibitory action of 5-HT. 5 Both indomethacin (2.8 x 10(-5) M) and ibuprofen (2.4 x 10(-4) M) antagonized the action of 5-HT. Indomethacin alone had no effect upon secretagogue responses. 6 5-HT at 10(-5) M had no inhibitory action when applied to the mucosal side of the preparation. 7 The results indicate that 5-HT can act directly on the stomach of the rat to produce inhibition of acid output. This inhibition is selective and may involve the products of cyclo-oxygenase activity. PMID:6824810

Canfield, S. P.; Spencer, J. E.

1983-01-01

303

Pharmacokinetics and bone tissue concentrations of lincomycin following intravenous and intramuscular administrations to cats.  

PubMed

The pharmacokinetic properties and bone concentrations of lincomycin in cats after single intravenous and intramuscular administrations at a dosage rate of 10 mg/kg were investigated. Lincomycin minimum inhibitory concentration (MIC) for some gram-positive strains isolated from clinical cases was determined. Serum lincomycin disposition was best-fitted to a bicompartmental and a monocompartmental open models with first-order elimination after intravenous and intramuscular dosing, respectively. After intravenous administration, distribution was rapid (T(1/2(d)) = 0.22 ± 0.09 h) and wide as reflected by the volume of distribution (V((d(ss)))) of 1.24 ± 0.08 L/kg. Plasma clearance was 0.28 ± 0.09 L/h · kg and elimination half-life (T(1/2)) 3.56 ± 0.62 h. Peak serum concentration (C(max)), T(max), and bioavailability for the intramuscular administration were 7.97 ± 2.31 ?g/mL, 0.12 ± 0.05 h, and 82.55 ± 23.64%, respectively. Thirty to 45 min after intravenous administration, lincomycin bone concentrations were 9.31 ± 1.75 ?g/mL. At the same time after intramuscular administration, bone concentrations were 3.53 ± 0.28 ?g/mL. The corresponding bone/serum ratios were 0.77 ± 0.04 (intravenous) and 0.69 ± 0.18 (intramuscular). Lincomycin MIC for Staphylococcus spp. ranged from 0.25 to 16 ?g/mL and for Streptococcus spp. from 0.25 to 8 ?g/mL. PMID:22132730

Albarellos, G A; Montoya, L; Denamiel, G A A; Velo, M C; Landoni, M F

2012-12-01

304

Mapping Inhibitory Neuronal Circuits by Laser Scanning Photostimulation  

PubMed Central

Inhibitory neurons are crucial to cortical function. They comprise about 20% of the entire cortical neuronal population and can be further subdivided into diverse subtypes based on their immunochemical, morphological, and physiological properties1-4. Although previous research has revealed much about intrinsic properties of individual types of inhibitory neurons, knowledge about their local circuit connections is still relatively limited3,5,6. Given that each individual neuron's function is shaped by its excitatory and inhibitory synaptic input within cortical circuits, we have been using laser scanning photostimulation (LSPS) to map local circuit connections to specific inhibitory cell types. Compared to conventional electrical stimulation or glutamate puff stimulation, LSPS has unique advantages allowing for extensive mapping and quantitative analysis of local functional inputs to individually recorded neurons3,7-9. Laser photostimulation via glutamate uncaging selectively activates neurons perisomatically, without activating axons of passage or distal dendrites, which ensures a sub-laminar mapping resolution. The sensitivity and efficiency of LSPS for mapping inputs from many stimulation sites over a large region are well suited for cortical circuit analysis. Here we introduce the technique of LSPS combined with whole-cell patch clamping for local inhibitory circuit mapping. Targeted recordings of specific inhibitory cell types are facilitated by use of transgenic mice expressing green fluorescent proteins (GFP) in limited inhibitory neuron populations in the cortex3,10, which enables consistent sampling of the targeted cell types and unambiguous identification of the cell types recorded. As for LSPS mapping, we outline the system instrumentation, describe the experimental procedure and data acquisition, and present examples of circuit mapping in mouse primary somatosensory cortex. As illustrated in our experiments, caged glutamate is activated in a spatially restricted region of the brain slice by UV laser photolysis; simultaneous voltage-clamp recordings allow detection of photostimulation-evoked synaptic responses. Maps of either excitatory or inhibitory synaptic input to the targeted neuron are generated by scanning the laser beam to stimulate hundreds of potential presynaptic sites. Thus, LSPS enables the construction of detailed maps of synaptic inputs impinging onto specific types of inhibitory neurons through repeated experiments. Taken together, the photostimulation-based technique offers neuroscientists a powerful tool for determining the functional organization of local cortical circuits. PMID:22006064

Ikrar, Taruna; Olivas, Nicholas D.; Shi, Yulin; Xu, Xiangmin

2011-01-01

305

Training-induced behavioral and brain plasticity in inhibitory control  

PubMed Central

Deficits in inhibitory control, the ability to suppress ongoing or planned motor or cognitive processes, contribute to many psychiatric and neurological disorders. The rehabilitation of inhibition-related disorders may therefore benefit from neuroplasticity-based training protocols aiming at normalizing inhibitory control proficiency and the underlying brain networks. Current literature on training-induced behavioral and brain plasticity in inhibitory control suggests that improvements may follow either from the development of automatic forms of inhibition or from the strengthening of top-down, controlled inhibition. Automatic inhibition develops in conditions of consistent and repeated associations between inhibition-triggering stimuli and stopping goals. Once established, the stop signals directly elicit inhibition, thereby bypassing slow, top-down executive control and accelerating stopping processes. In contrast, training regimens involving varying stimulus-response associations or frequent inhibition failures prevent the development of automatic inhibition and thus strengthen top-down inhibitory processes rather than bottom-up ones. We discuss these findings in terms of developing optimal inhibitory control training regimens for rehabilitation purposes. PMID:23914169

Spierer, Lucas; Chavan, Camille F.; Manuel, Aurelie L.

2013-01-01

306

Diffusion dynamics of synaptic molecules during inhibitory postsynaptic plasticity  

PubMed Central

The plasticity of inhibitory transmission is expected to play a key role in the modulation of neuronal excitability and network function. Over the last two decades, the investigation of the determinants of inhibitory synaptic plasticity has allowed distinguishing presynaptic and postsynaptic mechanisms. While there has been a remarkable progress in the characterization of presynaptically-expressed plasticity of inhibition, the postsynaptic mechanisms of inhibitory long-term synaptic plasticity only begin to be unraveled. At postsynaptic level, the expression of inhibitory synaptic plasticity involves the rearrangement of the postsynaptic molecular components of the GABAergic synapse, including GABAA receptors, scaffold proteins and structural molecules. This implies a dynamic modulation of receptor intracellular trafficking and receptor surface lateral diffusion, along with regulation of the availability and distribution of scaffold proteins. This Review will focus on the mechanisms of the multifaceted molecular reorganization of the inhibitory synapse during postsynaptic plasticity, with special emphasis on the key role of protein dynamics to ensure prompt and reliable activity-dependent adjustments of synaptic strength. PMID:25294987

Petrini, Enrica Maria; Barberis, Andrea

2014-01-01

307

"Ready, Set, Go": Checkpoint regulation by Cdk1 inhibitory phosphorylation.  

PubMed

ABSTRACT Cell cycle checkpoints prevent mitosis from occurring before DNA replication and repair are completed during S and G2 phases. The checkpoint mechanism involves inhibitory phosphorylation of Cdk1, a conserved kinase that regulates the onset of mitosis. Metazoans have two distinct Cdk1 inhibitory kinases with specialized developmental functions: Wee1 and Myt1. Ayeni et al used transgenic Cdk1 phospho-acceptor mutants to analyze how the distinct biochemical properties of these kinases affected their functions. They concluded from their results that phosphorylation of Cdk1 on Y15 was necessary and sufficient for G2/M checkpoint arrest in imaginal wing discs, whereas phosphorylation on T14 promoted chromosome stability by a different mechanism. A curious relationship was also noted between Y15 inhibitory phosphorylation and T161 activating phosphorylation. These unexpected complexities in Cdk1 inhibitory phosphorylation demonstrate that the checkpoint mechanism is not a simple binary "off/on" switch, but has at least three distinct states: "Ready", to prevent chromosome damage and apoptosis, "Set", for developmentally regulated G2 phase arrest, and "Go", when Cdc25 phosphatases remove inhibitory phosphates to trigger Cdk1 activation at the G2/M transition. PMID:25483135

Ayeni, Jo; Campbell, Sd

2014-07-01

308

47 CFR 73.807 - Minimum distance separation between stations.  

Code of Federal Regulations, 2010 CFR

... Minimum distance separation between stations. 73.807 Section 73.807 Telecommunication...BROADCAST SERVICES Low Power FM Broadcast Stations (LPFM) § 73.807 Minimum distance separation between stations. Minimum separation...

2010-10-01

309

47 CFR 73.507 - Minimum distance separations between stations.  

Code of Federal Regulations, 2010 CFR

... Minimum distance separations between stations. 73.507 Section 73.507 Telecommunication...Noncommercial Educational FM Broadcast Stations § 73.507 Minimum distance separations between stations. (a) Minimum distance...

2010-10-01

310

7 CFR 701.110 - Qualifying minimum cost of restoration.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Qualifying minimum cost of restoration. 701.110 ...Program § 701.110 Qualifying minimum cost of restoration. (a) To...request a waiver of the qualifying minimum cost of restoration. The...

2011-01-01

311

7 CFR 701.210 - Qualifying minimum cost of restoration.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Qualifying minimum cost of restoration. 701.210 ...Program § 701.210 Qualifying minimum cost of restoration. (a) FSA will...request a waiver of the qualifying minimum cost of restoration. The waiver...

2011-01-01

312

48 CFR 1828.372 - Clause for minimum insurance coverage.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Clause for minimum insurance coverage. 1828...Insurance 1828.372 Clause for minimum insurance coverage. ...stated at 1852.228-75, Minimum Insurance Coverage, in fixed-price solicitations and in cost-reimbursement...

2011-10-01

313

48 CFR 1828.372 - Clause for minimum insurance coverage.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 true Clause for minimum insurance coverage. 1828...Insurance 1828.372 Clause for minimum insurance coverage. ...stated at 1852.228-75, Minimum Insurance Coverage, in fixed-price solicitations and in cost-reimbursement...

2010-10-01

314

7 CFR 701.10 - Qualifying minimum cost of restoration.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Qualifying minimum cost of restoration. 701.10 Section...PART § 701.10 Qualifying minimum cost of restoration. (a) To...request a waiver of the qualifying minimum cost of restoration. The...

2010-01-01

315

50 CFR 648.93 - Monkfish minimum fish sizes.  

Code of Federal Regulations, 2013 CFR

...2013-10-01 false Monkfish minimum fish sizes. 648.93 Section 648.93...Fisheries § 648.93 Monkfish minimum fish sizes. (a) General provisions. ...Federal monkfish permit must meet the minimum fish size requirements established in this...

2013-10-01

316

50 CFR 648.93 - Monkfish minimum fish sizes.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false Monkfish minimum fish sizes. 648.93 Section 648.93...Fisheries § 648.93 Monkfish minimum fish sizes. (a) General provisions. ...Federal monkfish permit must meet the minimum fish size requirements established in this...

2011-10-01

317

50 CFR 648.93 - Monkfish minimum fish sizes.  

Code of Federal Regulations, 2012 CFR

...2012-10-01 false Monkfish minimum fish sizes. 648.93 Section 648.93...Fisheries § 648.93 Monkfish minimum fish sizes. (a) General provisions. ...Federal monkfish permit must meet the minimum fish size requirements established in this...

2012-10-01

318

50 CFR 648.93 - Monkfish minimum fish sizes.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 false Monkfish minimum fish sizes. 648.93 Section 648.93...Fisheries § 648.93 Monkfish minimum fish sizes. (a) General provisions. ...Federal monkfish permit must meet the minimum fish size requirements established in this...

2010-10-01

319

7 CFR 953.43 - Minimum standards of quality.  

Code of Federal Regulations, 2011 CFR

...2011-01-01 false Minimum standards of quality. 953.43 Section 953...Regulations § 953.43 Minimum standards of quality. (a) Recommendation...establish and maintain minimum standards of quality governing the shipment...

2011-01-01

320

7 CFR 953.43 - Minimum standards of quality.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Minimum standards of quality. 953.43 Section 953...Regulations § 953.43 Minimum standards of quality. (a) Recommendation...establish and maintain minimum standards of quality governing the shipment...

2010-01-01

321

acetylcholinesterase inhibitory potential and insecticidal activity of an endophytic Alternaria sp. from Ricinus communis.  

PubMed

Keeping in view the vast potential of endophytic fungi to produce bioactive molecules, this study aimed at isolating and screening endophytes for the production of acetylcholinesterase inhibitors. Fifty-four endophytic fungi were isolated from Ricinus communis and screened for their AChE inhibitory activity using Ellman's colorimetric assay method. Six isolates were found to possess AChE inhibitory activity with maximum inhibition of 78 % being evinced by culture Cas1 which was identified to be Alternaria sp. on the basis of molecular as well as microscopic methods. Optimization of inhibitor production was carried out using one factor at a time approach. Maximum production of inhibitor was obtained on potato dextrose broth after 10 days incubation. The IC(50) of the chloroform extract was observed to be 40 ?g/ml. The extract was purified on silica gel and eluted stepwise with a gradient of chloroform/methanol. The insecticidal potential of the extract was evaluated by feeding the larvae of Spodoptera litura on diet containing varying concentrations of the extract. It was observed that with increase in the concentration of the extract, mortality of the larvae increased. The culture has the potential of being exploited in medicine as well as a biocontrol agent. PMID:22945561

Singh, Bahaderjeet; Thakur, Abhinay; Kaur, Sanehdeep; Chadha, B S; Kaur, Amarjeet

2012-11-01

322

Inhibitory effects of fruit flavors on methane production during anaerobic digestion.  

PubMed

In order to improve biogas production from fruit wastes, the inhibitory effects of fruit flavors on anaerobic digestion were investigated. Batch anaerobic digestion was performed for 30 days using synthetic medium and thermophilic sludge. Three groups of flavor compounds i.e. aldehydes (hexanal, nonanal, and E-2-hexenal), terpenes (car-3-ene, ?-pinene, and myrcene), and alcohol (octanol) at concentration of 0.005%, 0.05%, and 0.5% were examined. All the flavor compounds showed inhibitory effect on methane production. The highest methane reduction was obtained at addition of 0.5% of flavor compounds. For terpenoids, the presence of 0.5% of car-3-ene, myrcene, and ?-pinene reduced 95%, 75%, and 77% of methane production, respectively. For aldehydes, addition of 0.5% concentration resulted in more than 99% methane reduction for hexanal and E-2-hexenal, and 84% methane reduction for nonanal. For alcohol, the presence of 0.5% octanol decreased 99% methane production. PMID:23422220

Wikandari, Rachma; Gudipudi, Sailaja; Pandiyan, Ishwarya; Millati, Ria; Taherzadeh, Mohammad J

2013-10-01

323

Aldose Reductase Inhibitory Activity of Compounds from??Zea mays L.  

PubMed Central

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??M). 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

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

2013-01-01

324

Flavonoids from Machilus japonica Stems and Their Inhibitory Effects on LDL Oxidation  

PubMed Central

Stems of Machilus japonica were extracted with 80% aqueous methanol (MeOH) and the concentrated extract was successively extracted with ethyl acetate (EtOAc), normal butanol (n-BuOH), and water. Six flavonoids were isolated from the EtOAc fraction: (+)-taxifolin, afzelin, (?)-epicatechin, 5,3'-di-O-methyl-(?)-epicatechin, 5,7,3'-tri-O-methyl-(?)-epicatechin, and 5,7-di-O-methyl-3',4'-methylenedioxyflavan-3-ol. The chemical structures were identified using spectroscopic data including NMR, mass spectrometry and infrared spectroscopy. This is the first report of isolation of these six compounds from M. japonica. The compounds were evaluated for their diphenyl picryl hydrazinyl scavenging activity and inhibitory effects on low-density lipoprotein oxidation. Compounds 1 and 3–6 exhibited DPPH antioxidant activity equivalent with that of ascorbic acid, with half maximal inhibitory concentration (IC50) values of 0.16, 0.21, 0.17, 0.15 and 0.07 mM, respectively. The activity of compound 1 was similar to the positive control butylated hydroxytoluene, which had an IC50 value of 1.9 µM, while compounds 3 and 5 showed little activity. Compounds 1, 3, and 5 exhibited LDL antioxidant activity with IC50 values of 2.8, 7.1, and 4.6 µM, respectively. PMID:25229822

Joo, Se-Jin; Park, Hee-Jung; Park, Ji-Hae; Cho, Jin-Gyeong; Kang, Ji-Hyun; Jeong, Tae-Sook; Kang, Hee Cheol; Lee, Dae-Young; Kim, Hack-Soo; Byun, Sang-Yo; Baek, Nam-In

2014-01-01

325

Reward breaks through the inhibitory region around attentional focus.  

PubMed

It is well known that directing attention to a location in space enhances the processing efficiency of stimuli presented at that location. Research has also shown that around this area of enhanced processing, there is an inhibitory region within which processing of information is suppressed. In this study, we investigated whether a reward-associated stimulus can break through the inhibitory surround. A distractor that was previously associated with high or low reward was presented near the target with a variable distance between them. For low-reward distractors, only the distractor very close to the target caused interference to target processing; for high-reward distractors, both near and relatively far distractors caused interference, demonstrating that task-irrelevant reward-associated stimuli can capture attention even when presented within the inhibitory surround. PMID:25280985

Wang, Lihui; Duan, Yunyan; Theeuwes, Jan; Zhou, Xiaolin

2014-01-01

326

Arginase II inhibitory activity of flavonoid compounds from Scutellaria indica.  

PubMed

Arginase II has recently reported as a novel therapeutic target for the treatment of cardiovascular diseases such as atherosclerosis. In the course of screening plants used in natural medicines as arginase II inhibitory activity, a methanol extract of Scutellaria indica showed significant inhibitory effect. Further fractionation and repeated column chromatography led to the isolation of a new flavan-type (1), and seven known compounds (2-8). The chemical structures of isolated compounds were elucidated based on extensive 1D and 2D NMR spectroscopic data. The isolates 1-8 were investigated in vitro for their arginase II inhibitory activity using enzyme solution prepared from kidney of anesthetized C57BL/6 mice. Compounds 3 and 5 significantly inhibited arginase II activity with IC?? values of 25.1 and 11.6 ?M, respectively, whereas the other compounds were apparently inactive. PMID:23604721

Kim, Sang Won; Cuong, To Dao; Hung, Tran Manh; Ryoo, Sungwoo; Lee, Jeong Hyung; Min, Byung Sun

2013-08-01

327

Adaptive Proactive Inhibitory Control for Embedded Real-Time Applications  

PubMed Central

Psychologists have studied the inhibitory control of voluntary movement for many years. In particular, the countermanding of an impending action has been extensively studied. In this work, we propose a neural mechanism for adaptive inhibitory control in a firing-rate type model based on current findings in animal electrophysiological and human psychophysical experiments. We then implement this model on a field-programmable gate array (FPGA) prototyping system, using dedicated real-time hardware circuitry. Our results show that the FPGA-based implementation can run in real-time while achieving behavioral performance qualitatively suggestive of the animal experiments. Implementing such biological inhibitory control in an embedded device can lead to the development of control systems that may be used in more realistic cognitive robotics or in neural prosthetic systems aiding human movement control. PMID:22701420

Yang, Shufan; McGinnity, T. Martin; Wong-Lin, KongFatt

2012-01-01

328

Inhibitory control after traumatic brain injury in children.  

PubMed

Inhibitory control describes a number of distinct processes. Effortless inhibition refers to acts of control that are automatic and reflexive. Effortful inhibition refers to voluntary, goal-directed acts of control such as response flexibility, interference control, cancellation inhibition, and restraint inhibition. Disruptions to a number of inhibitory control processes occur as a consequence of childhood traumatic brain injury (TBI). This paper reviews the current knowledge of inhibition deficits following childhood TBI, and includes an overview of the inhibition construct and a discussion of the specific deficits shown by children and adolescents with TBI and the factors that mediate the expression of these deficits, including injury-related variables and the expression of pre- and post-injury attention-deficit/hyperactivity disorder. The review illustrates that inhibitory control processes differ in terms of measurement, assessment, and neurological underpinnings, and also that childhood TBI may selectively disrupt particular forms of inhibition. PMID:22100363

Sinopoli, Katia J; Dennis, Maureen

2012-05-01

329

Inhibitory effects of herbal extracts on breast cancer resistance protein (BCRP) and structure-inhibitory potency relationship of isoflavonoids.  

PubMed

The inhibition of intestinal breast cancer resistance protein (BCRP), which restricts the absorption of xenobiotics, may increase the systemic availability of its substrates. The aim of this study was to evaluate the inhibitory effects of herbal extracts and their constituents on BCRP-mediated transport. The inhibitory effects of 9 herbal extracts and 23 isoflavonoids, including soybean-derived isoflavones, on BCRP-mediated methotrexate (MTX) transport were evaluated using BCRP-expressing membrane vesicles. The structure-inhibitory potency relationship was investigated by multiple factor analysis. Extracts of soybean, Gymnema sylvestre, black cohosh and passion flower and rutin strongly inhibited BCRP-mediated transport of MTX at 1 mg/ml, while inhibition by chlorella, milk thistle and Siberian ginseng extracts was weak. Among the 23 isoflavonoids examined, all of which inhibited BCRP-mediated transport, coumestrol showed the most potent inhibition (IC(50)=63 nM). The inhibitory potencies of 6 isoflavonoid glucosides were 10- to 100-fold lower than those of the corresponding aglycones. The addition of a 5-hydroxyl or 6-methoxyl moiety tended to potentiate the inhibition. The inhibitory potency of daidzein was decreased 100-fold by 7-glucuronidation, but was virtually unaffected by 4'-sulfation. Thus, some herbal and dietary supplements and isoflavonoids may increase the systemic availability of BCRP substrates when concomitantly given orally. PMID:20460823

Tamaki, Hirofumi; Satoh, Hiroki; Hori, Satoko; Ohtani, Hisakazu; Sawada, Yasufumi

2010-01-01

330

Risk control and the minimum significant risk  

SciTech Connect

Risk management implies that the risk manager can, by his actions, exercise at least a modicum of control over the risk in question. In the terminology of control theory, a management action is a control signal imposed as feedback on the system to bring about a desired change in the state of the system. In the terminology of risk management, an action is taken to bring a predicted risk to lower values. Even if it is assumed that the management action taken is 100% effective and that the projected risk reduction is infinitely well known, there is a lower limit to the desired effects that can be achieved. It is based on the fact that all risks, such as the incidence of cancer, exhibit a degree of variability due to a number of extraneous factors such as age at exposure, sex, location, and some lifestyle parameters such as smoking or the consumption of alcohol. If the control signal is much smaller than the variability of the risk, the signal is lost in the noise and control is lost. This defines a minimum controllable risk based on the variability of the risk over the population considered. This quantity is the counterpart of the minimum significant risk which is defined by the uncertainties of the risk model. Both the minimum controllable risk and the minimum significant risk are evaluated for radiation carcinogenesis and are shown to be of the same order of magnitude. For a realistic management action, the assumptions of perfectly effective action and perfect model prediction made above have to be dropped, resulting in an effective minimum controllable risk which is determined by both risk limits. Any action below that effective limit is futile, but it is also unethical due to the ethical requirement of doing more good than harm. Finally, some implications of the effective minimum controllable risk on the use of the ALARA principle and on the evaluation of remedial action goals are presented.

Seiler, F.A. [IT Corp., Albuquerque, NM (United States); Alvarez, J.L. [Auxier & Associates, Parker, CO (United States)

1996-06-01

331

Inhibitory and excitatory effects of dopamine on Aplysia neurones  

PubMed Central

1. Electrophoretic application of dopamine (DA) on Aplysia neurones elicits both excitatory and inhibitory effects, which in many cases are observed in the same neurone, and often result in a biphasic response. 2. The DA receptors are localized predominantly on the axons. Desensitization, which occurs after repeated injections or with bath application of DA, is more marked for excitatory responses. 3. Tubocurarine and strychnine block the DA excitatory responses without affecting the inhibitory ones, which can be selectively blocked by ergot derivatives. It is concluded that the excitatory and inhibitory effects are mediated by two distinct receptors. 4. The two DA receptors can be pharmacologically separated from the three ACh receptors described in the same nervous system. 5. In some neurones the dopamine inhibitory responses can be inverted by artificial hyperpolarization of the membrane at the potassium equilibrium potential, EK, indicating that dopamine causes a selective increase in potassium permeability. 6. In other neurones the reversal potential of dopamine inhibitory responses is at a more depolarized level than EK, but can be brought to EK by pharmacological agents known to block the receptors mediating the excitatory effects of DA. 7. In still other neurones, the hyperpolarization induced by DA cannot be inverted in normal conditions, but a reversal can be induced by ouabain or by the substitution of external sodium by lithium. These results are discussed in terms of an hypothesis in which dopamine increases the potassium permeability of a limited region of the axonal membrane. 8. It is concluded that a selective increase in potassium permeability probably accounts for all dopamine inhibitory effects in the neurones studied. PMID:4679683

Ascher, P.

1972-01-01

332

Image data compression having minimum perceptual error  

NASA Technical Reports Server (NTRS)

A method for performing image compression that eliminates redundant and invisible image components is described. The image compression uses a Discrete Cosine Transform (DCT) and each DCT coefficient yielded by the transform is quantized by an entry in a quantization matrix which determines the perceived image quality and the bit rate of the image being compressed. The present invention adapts or customizes the quantization matrix to the image being compressed. The quantization matrix comprises visual masking by luminance and contrast techniques and by an error pooling technique all resulting in a minimum perceptual error for any given bit rate, or minimum bit rate for a given perceptual error.

Watson, Andrew B. (inventor)

1995-01-01

333

Image Data Compression Having Minimum Perceptual Error  

NASA Technical Reports Server (NTRS)

A method is presented for performing color or grayscale image compression that eliminates redundant and invisible image components. The image compression uses a Discrete Cosine Transform (DCT) and each DCT coefficient yielded by the transform is quantized by an entry in a quantization matrix which determines the perceived image quality and the bit rate of the image being compressed. The quantization matrix comprises visual masking by luminance and contrast technique all resulting in a minimum perceptual error for any given bit rate, or minimum bit rate for a given perceptual error.

Watson, Andrew B. (Inventor)

1997-01-01

334

Minimum induced drag configurations with jet interaction  

NASA Technical Reports Server (NTRS)

A theoretical method is presented for determining the optimum camber shape and twist distribution for the minimum induced drag in the wing-alone case without prescribing the span loading shape. The same method was applied to find the corresponding minimum induced drag configuration with the upper-surface-blowing jet. Lan's quasi-vortex-lattice method and his wing-jet interaction theory was used. Comparison of the predicted results with another theoretical method shows good agreement for configurations without the flowing jet. More applicable experimental data with blowing jets are needed to establish the accuracy of the theory.

Pao, J. L.; Lan, C. E.

1978-01-01

335

Deep solar minimum and global climate changes  

PubMed Central

This paper examines the deep minimum of solar cycle 23 and its potential impact on climate change. In addition, a source region of the solar winds at solar activity minimum, especially in the solar cycle 23, the deepest during the last 500 years, has been studied. Solar activities have had notable effect on palaeoclimatic changes. Contemporary solar activity are so weak and hence expected to cause global cooling. Prevalent global warming, caused by building-up of green-house gases in the troposphere, seems to exceed this solar effect. This paper discusses this issue.

Hady, Ahmed A.

2013-01-01

336

Deep solar minimum and global Climate Changes  

NASA Astrophysics Data System (ADS)

This paper examines the deep minimum of solar cycle 23 and its likely impact on climate change. In addition, a source region of the solar winds at solar activity minimum, especially in the solar cycle 23, the deepest during the last 100 years, has been studied. Solar activities have had notable effect on palaeoclimatic changes. Contemporary solar activities are so weak and hence expected to cause global cooling. Prevalent global warming, caused by building-up of green-house gases in the troposphere, seems to exceed this solar effect. This paper discusses this issue.

Abdel Hady, Ahmed

2012-07-01

337

Deep solar minimum and global climate changes  

NASA Astrophysics Data System (ADS)

This paper examines the deep minimum of solar cycle 23 and its potential impact on climate change. In addition, a source region of the solar winds at solar activity minimum, especially in the solar cycle 23, the deepest during the last 500 years, has been studied. Solar activities have had notable effect on palaeoclimatic changes. Contemporary solar activity are so weak and hence expected to cause global cooling. Prevalent global warming, caused by building-up of green-house gases in the troposphere, seems to exceed this solar effect. This paper discusses this issue.

Hady, Ahmed A.

2013-05-01

338

Optimization for minimum sensitivity to uncertain parameters  

NASA Technical Reports Server (NTRS)

A procedure to design a structure for minimum sensitivity to uncertainties in problem parameters is described. The approach is to minimize directly the sensitivity derivatives of the optimum design with respect to fixed design parameters using a nested optimization procedure. The procedure is demonstrated for the design of a bimetallic beam for minimum weight with insensitivity to uncertainties in structural properties. The beam is modeled with finite elements based on two dimensional beam analysis. A sequential quadratic programming procedure used as the optimizer supplies the Lagrange multipliers that are used to calculate the optimum sensitivity derivatives. The method was perceived to be successful from comparisons of the optimization results with parametric studies.

Pritchard, Jocelyn I.; Adelman, Howard M.; Sobieszczanski-Sobieski, Jaroslaw

1994-01-01

339

Minimum error discrimination of Pauli channels  

E-print Network

We solve the problem of discriminating with minimum error probability two given Pauli channels. We show that, differently from the case of discrimination between unitary transformations, the use of entanglement with an ancillary system can strictly improve the discrimination, and any maximally entangled state allows to achieve the optimal discrimination. We also provide a simple necessary and sufficient condition in terms of the structure of the channels for which the ultimate minimum error probability can be achieved without entanglement assistance. When such a condition is satisfied, the optimal input state is simply an eigenstate of one of the Pauli matrices.

Massimiliano F. Sacchi

2005-06-09

340

Inhibitory effects of insulin on GABAA currents modulated by the GABAA alpha subunit.  

PubMed

Abstract Insulin, when co-applied with GABA, can cause an inhibition of the induced current at GABAA receptors. This study investigated that inhibitory effect of insulin at a variety of receptor isoforms, concentrating on ?1, ?2 and ?4 containing receptors. Various isoforms were expressed in Xenopus oocytes and currents determined using two-electrode voltage clamp. Submaximal GABA currents at all isoforms studied were inhibited by nanomolar concentrations of insulin. At ?2 and ?4 containing forms, insulin could inhibit maximal GABA currents. The ability to inhibit maximal currents, and the general potency and effects at submaximal currents paralleled the number of potential MAPK sites on the ? subunits. The differences in insulin inhibition of GABA currents at different ? containing GABAA receptors could be important in autocrine and paracrine control of hormone secretion in the pancreas, and in control of reward and food intake circuits of the brain. PMID:25224408

Williams, Daniel B

2014-09-16

341

Inhibitory processes in toddlers: a latent-variable approach  

PubMed Central

The aim of this study was to investigate the nature of inhibitory processes in early childhood. A confirmatory factor analysis was used to examine the latent structure of inhibitory processes in day-care center children aged 24–32 months and in preschool children aged 36–48 months. The best fit to the data for the younger sample was a single undifferentiated inhibition factor model; in older children, a two-factor model was differently identified in which response inhibition and interference suppression were distinguished. PMID:24817858

Gandolfi, Elena; Viterbori, Paola; Traverso, Laura; Usai, M. Carmen

2014-01-01

342

Time Crystals from Minimum Time Uncertainty  

E-print Network

Motivated by the Generalized Uncertainty Principle, covariance, and a minimum measurable time, we propose a deformation of the Heisenberg algebra, and show that this leads to corrections to all quantum mechanical systems. We also demonstrate that such a deformation implies a discrete spectrum for time. In other words, time behaves like a crystal.

Faizal, Mir; Das, Saurya

2015-01-01

343

Time Crystals from Minimum Time Uncertainty  

E-print Network

Motivated by the Generalized Uncertainty Principle, covariance, and a minimum measurable time, we propose a deformation of the Heisenberg algebra, and show that this leads to corrections to all quantum mechanical systems. We also demonstrate that such a deformation implies a discrete spectrum for time. In other words, time behaves like a crystal.

Mir Faizal; Mohammed M. Khalil; Saurya Das

2014-12-29

344

Solar Radius at Minimum of Cycle 23  

NASA Astrophysics Data System (ADS)

Observations of Baily beads in French Guyana, during 2006 September 22 annular eclipse, have been made to measure solar radius around solar minimum activity of cycle 23. The correction to standard solar radius at unit distance (1 AU) 959.63" to fit observations is ?R? = -0.01" ± 0.17". Sources of errors are outlined in view of relativistic accuracies.

Sigismondi, Costantino

2008-09-01

345

Iterated Local Optimization for Minimum Energy Broadcast  

Microsoft Academic Search

Abstract In our prior work, we presented a highly effective lo- cal search based heuristic algorithm called the Largest Expanding Sweep Search (LESS) to solve the minimum energy broadcast (MEB) problem over wireless ad hoc or sensor networks. In this paper, the performance is further strengthened by using iterated local optimiza- tion (ILO) techniques at the cost of additional compu-

Intae Kang; Radha Poovendran

2005-01-01

346

2013 Missouri Minimum Standards for School Buses  

ERIC Educational Resources Information Center

The revised minimum standards for school bus chassis and school bus bodies have been prepared in conformity with the Revised Statutes of Missouri (RSMo) for school bus transportation. The standards recommended by the 2010 National Conference on School Transportation and the Federal Motor Vehicle Safety Standards (FMVSS) promulgated by the U. S.…

Nicastro, Chris L.

2012-01-01

347

Menu Plans: Maximum Nutrition for Minimum Cost.  

ERIC Educational Resources Information Center

Suggests that menu planning is the key to getting maximum nutrition in day care meals and snacks for minimum cost. Explores United States Department of Agriculture food pyramid guidelines for children and tips for planning menus and grocery shopping. Includes suggested meal patterns and portion sizes. (HTH)

Texas Child Care, 1995

1995-01-01

348

24 CFR 35.155 - Minimum requirements.  

Code of Federal Regulations, 2011 CFR

(a) Nothing in subparts B, C, D, F through M, and R of this part is intended to preclude a designated party or occupant from conducting additional evaluation or hazard reduction measures beyond the minimum requirements established for each program in this...

2011-04-01

349

Minimum Description Length Shape and Appearance Models  

E-print Network

://www.imm.dtu.dk/~hht IMM TECHNICAL REPORT 2003-01 Submitted Feb 14, 2003 to Information Processing in Medical Imaging 2003 and the examples are published to facilitate the dissemination of this technique in medical imaging and other, Unsupervised Vision, Image Segmentation. Abstract. The Minimum Description Length (MDL) approach to shape model

350

Minimum Description Length Shape and Appearance Models  

E-print Network

: http://www.imm.dtu.dk/~hht Published in proceedings of Information Processing in Medical Imaging, IPMI. The Matlab code and the examples are published to facilitate the dissemination of this technique in medical Correspondence Problem, Unsupervised Vision, Image Segmentation. Abstract. The Minimum Description Length (MDL

351

Minimum Description Length Shape and Appearance Models  

Microsoft Academic Search

The Minimum Description Length (MDL) approach to shape model- ling is reviewed. It solves the point correspondence problem of selecting points on shapes defined as curves so that the points correspond across a data set. An efficient numerical implementation is presented and made available as open source Matlab code. The problems with the early MDL approaches are dis- cussed. Finally

Hans Henrik Thodberg

2003-01-01

352

Model selection for minimum-diameter partitioning.  

PubMed

The minimum-diameter partitioning problem (MDPP) seeks to produce compact clusters, as measured by an overall goodness-of-fit measure known as the partition diameter, which represents the maximum dissimilarity between any two objects placed in the same cluster. Complete-linkage hierarchical clustering is perhaps the best-known heuristic method for the MDPP and has an extensive history of applications in psychological research. Unfortunately, this method has several inherent shortcomings that impede the model selection process, such as: (1) sensitivity to the input order of the objects, (2) failure to obtain a globally optimal minimum-diameter partition when cutting the tree at K clusters, and (3) the propensity for a large number of alternative minimum-diameter partitions for a given K. We propose that each of these problems can be addressed by applying an algorithm that finds all of the minimum-diameter partitions for different values of K. Model selection is then facilitated by considering, for each value of K, the reduction in the partition diameter, the number of alternative optima, and the partition agreement among the alternative optima. Using five examples from the empirical literature, we show the practical value of the proposed process for facilitating model selection for the MDPP. PMID:24192201

Brusco, Michael J; Steinley, Douglas

2014-11-01

353

University Scholarships Minimum Credit Hour Contract  

E-print Network

University Scholarships Minimum Credit Hour Contract · If you are a recipient of a university for either the 28-Credit Hour Alternative OR the Credit Hour Reduction for Final Enrollment. 28-Credit Hour Alternative Once you have been notified of a scholarship, you may contract to complete 28 credit hours during

Olsen Jr., Dan R.

354

Fast Algorithms for the Minimum Volume Estimator  

E-print Network

Aug 14, 2014 ... cent developments in the first-order algorithms for solving the related. Minimum ..... X with positive weight also happen to lie on the surface of the ellipsoid, ...... edge Discovery and Data Mining, Washington, D.C. USA, 29–38 (2003) ... [20] L. G. Khachiyan, Rounding of Polytopes in the Real Number Model of.

2014-08-14

355

Sea Ice Yearly Minimum in the Arctic  

NSDL National Science Digital Library

This series of visualizations show the annual Arctic sea ice minimum from 1979 to 2010. The decrease in Arctic sea ice over time is shown in an animation and a graph plotted simultaneously, but can be parsed so that the change in sea ice area can be shown without the graph.

GSFC/Science Visualization Studio

356

What's Happening in Minimum Competency Testing.  

ERIC Educational Resources Information Center

An examination of the current status of minimum competency testing is presented in a series of short essays, which discuss case studies of individual school systems and state approaches. Sections are also included on the viewpoints of critics and supporters, teachers and teacher organizations, principals and students, and the federal government.…

Frahm, Robert; Covington, Jimmie

357

24 CFR 35.155 - Minimum requirements.  

...for All Programs. § 35.155 Minimum requirements...in subparts B, C, D, F through M, and R...assessment in accordance with § 35.1320. Similarly, if...abatement in accordance with § 35.1325. (b) To the...subparts B, C, D, and F through M of this...

2014-04-01

358

24 CFR 35.155 - Minimum requirements.  

Code of Federal Regulations, 2012 CFR

...for All Programs. § 35.155 Minimum requirements...in subparts B, C, D, F through M, and R...assessment in accordance with § 35.1320. Similarly, if...abatement in accordance with § 35.1325. (b) To the...subparts B, C, D, and F through M of this...

2012-04-01

359

24 CFR 35.155 - Minimum requirements.  

Code of Federal Regulations, 2010 CFR

...for All Programs. § 35.155 Minimum requirements...in subparts B, C, D, F through M, and R...assessment in accordance with § 35.1320. Similarly, if...abatement in accordance with § 35.1325. (b) To the...subparts B, C, D, and F through M of this...

2010-04-01

360

24 CFR 35.155 - Minimum requirements.  

Code of Federal Regulations, 2013 CFR

...for All Programs. § 35.155 Minimum requirements...in subparts B, C, D, F through M, and R...assessment in accordance with § 35.1320. Similarly, if...abatement in accordance with § 35.1325. (b) To the...subparts B, C, D, and F through M of this...

2013-04-01

361

BE STRATEGIC! Borrow the Minimum You Need  

E-print Network

BE SMART! BE STRATEGIC! Borrow the Minimum You Need in Law School University of South Carolina Not prescriptive and NOT your budget COA Elements Tuition Fees Books and Supplies Housing Food Transportation,352 ($261/month) $ Transportation $1,665 ($185/month) $1,665 ($185/month) $ Miscellaneous personal $2

Almor, Amit

362

Network Flow Maximum Flow and Minimum Cut  

E-print Network

3/3/2011 1 1 Chapter 7 Network Flow 2 Maximum Flow and Minimum Cut Max flow and min cut. Two very duality. Nontrivial applications / reductions. Data mining. Open-pit mining. Project selection. Airline-camera scene reconstruction. Many many more ... 3 Flow network. Abstraction for material flowing through

Srinivasan, Padmini

363

The Minimum Guarding Tree Problem Adrian Dumitrescu  

E-print Network

The Minimum Guarding Tree Problem Adrian Dumitrescu Joseph S. B. Mitchell Pawel Zyli´nski September, a guarding tree for L is a tree contained in the union of the lines in L such that if a mobile guard (agent) runs on the edges of the tree, all lines in L are visited by the guard. Similarly, given a connected

Dumitrescu, Adrian

364

Growth inhibitory effect of peel extract from Citrus junos  

Microsoft Academic Search

Extract from yuzu fruit peel (Citrus junos Sieb. ex Tanaka) strongly suppressed the germination of lettuce seeds while that from the peel of other citrus fruits such as navel orange (C. sinensis) and lemon (C. limon Burm. f.) had very little or no effect. The highest inhibitory activity was located in the peel followed by the segment but no significant

Shinsuke Fujihara; Tokurou Shimizu

2003-01-01

365

The Effect of Social Observation on Children's Inhibitory Control  

ERIC Educational Resources Information Center

This study examined the effects of social observation on young children's performance during an inhibitory control task. In Experiment 1, children were randomly assigned to either a neutral, facilitation, or interference condition. In the neutral condition, children were presented with a standard black/white task. In the facilitation and…

Moriguchi, Yusuke

2012-01-01

366

Synthetic Antigens Reveal Dynamics of BCR Endocytosis during Inhibitory Signaling  

E-print Network

Synthetic Antigens Reveal Dynamics of BCR Endocytosis during Inhibitory Signaling Adam H. Courtney is endocytosis of the BCR complex, which acts to downregulate signaling and facilitate uptake of antigen for processing and display on the cell surface. The relationship between signaling and BCR endocytosis is poorly

Kiessling, Laura

367

Hunger, inhibitory control and distress-induced emotional eating.  

PubMed

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. PMID:24768894

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

2014-08-01

368

Investigation of UDP-glucuronosyltransferases (UGTs) inhibitory properties of carvacrol.  

PubMed

UDP-glucuronosyltransferases (UGTs), the most important phase II drug metabolizing enzymes (DMEs), could metabolize many drugs and various endogenous substances including bilirubin, steroid hormones, thyroid hormones, bile acids and fat-soluble vitamins. Evaluation of the inhibitory effects of compounds on UGTs is clinically important because inhibition of UGT isoforms could not only result in serious drug-drug interactions (DDIs), but also induce metabolic disorders of endogenous substances. The aim of the present study was to investigate the inhibitory effects of carvacrol on major UGT isoforms. The results showed that carvacrol could inhibit the activity of UGT1A9 with negligible effects on other UGT isoforms. When 4-methylumbelliferone (4-MU) was used as a nonspecific probe substrate and recombinant UGT enzymes were utilized as an enzyme resource, the inhibition of UGT1A9 was best fit to the competitive type and the inhibition kinetic parameter (K(i)) was calculated to be 5.7?µM. Furthermore, another specific probe substrate, propofol, was employed to determine the inhibitory kinetics of UGT1A9, and the results demonstrated that the inhibitory type was noncompetitive. The inhibition kinetic parameter (K(i)) was determined to be 25.0?µM. Because this substrate-dependent inhibition of UGT1A9 might confuse the in vitro-in vivo extrapolation, these in vitro inhibition kinetic parameters should be interpreted with special caution. PMID:21544887

Dong, Rui-Hua; Fang, Zhong-Ze; Zhu, Liang-Liang; Liang, Si-Cheng; Ge, Guang-Bo; Yang, Ling; Liu, Ze-Yuan

2012-01-01

369

Inhibitory Control of Proactive Interference in Adults With ADHD  

Microsoft Academic Search

Objective: Attention deficit hyperactivity disorder (ADHD) is associated with poor inhibition of prepotent responses and deficits in distractor inhibition, but relatively few studies have addressed inhibitory control of proactive interference (PI) in individuals with ADHD. Thus, the goal of the present study was to evaluate resistance to spatial and verbal PI in adults with ADHD. Method: Adults with ADHD (n

Holly A. White

2007-01-01

370

Inhibitory control gains from higher-order cognitive strategy training.  

PubMed

The present study examined the transfer of higher-order cognitive strategy training to inhibitory control. Middle school students enrolled in a comprehension- and reasoning-focused cognitive strategy training program and passive controls participated. The training program taught students a set of steps for inferring essential gist or themes from materials. Both before and after training or a comparable duration in the case of the passive controls, participants completed a semantically cued Go/No-Go task that was designed to assess the effects of depth of semantic processing on response inhibition and components of event-related potentials (ERP) related to response inhibition. Depth of semantic processing was manipulated by varying the level of semantic categorization required for response selection and inhibition. The SMART-trained group showed inhibitory control gains and changes in fronto-central P3 ERP amplitudes on inhibition trials; whereas, the control group did not. The results provide evidence of the transfer of higher-order cognitive strategy training to inhibitory control and modulation of ERPs associated with semantically cued inhibitory control. The findings are discussed in terms of implications for cognitive strategy training, models of cognitive abilities, and education. PMID:24286804

Motes, Michael A; Gamino, Jacquelyn F; Chapman, Sandra B; Rao, Neena K; Maguire, Mandy J; Brier, Matthew R; Kraut, Michael A; Hart, John

2014-02-01

371

The inhibitory effect of glycomacropeptide on dental erosion  

E-print Network

Note The inhibitory effect of glycomacropeptide on dental erosion Anita Setareh NEJAD*, Ara associated with a rise in dental problems such as caries and erosion. The aim of this study was to investigate the protective effect of glycomacropeptide (GMP) against dental erosion and to compare the effect

Paris-Sud XI, Université de

372

How Many Subtypes of Inhibitory Cells in the Hippocampus?  

Microsoft Academic Search

Hippocampal inhibitory cells are diverse. It is supposed that they fall into functionally distinct subsets defined by a similar morphology and physiology. Switching between functions could be accomplished by activating receptors for modulating transmitters expressed selectively by different subsets of interneurons. We tested this hypothesis by comparing morphology, physiology, and neurotransmitter receptor expression for CA1 hippocampal interneurons. We distinguished 16

Paula Parra; Attila I. Gulyas; Richard Miles

1998-01-01

373

Inhibitory Competition between Shape Properties in Figure-Ground Perception  

ERIC Educational Resources Information Center

Theories of figure-ground perception entail inhibitory competition between either low-level units (edge or feature units) or high-level shape properties. Extant computational models instantiate the 1st type of theory. The authors investigated a prediction of the 2nd type of theory: that shape properties suggested on the ground side of an edge are…

Peterson, Mary A.; Skow, Emily

2008-01-01

374

Inhibitory Control during Emotional Distraction across Adolescence and Early Adulthood  

ERIC Educational Resources Information Center

This study investigated the changing relation between emotion and inhibitory control during adolescence. One hundred participants between 11 and 25 years of age performed a go-nogo task in which task-relevant stimuli (letters) were presented at the center of large task-irrelevant images depicting negative, positive, or neutral scenes selected from…

Cohen-Gilbert, Julia E.; Thomas, Kathleen M.

2013-01-01

375

Estradiol: a rhythmic, inhibitory, indirect control of meal size  

Microsoft Academic Search

The classic analyses of the inhibitory effects of cholecystokinin (CCK) on meal size, conducted by Professor Gerard P. Smith and his colleagues at the Bourne Laboratory, inspired my initial interest in this field. My current research, which investigates the role of estradiol in the control of meal size, continues to be guided by Gerry's thoughtful, scientific approach to the study

Lisa A. Eckel

2004-01-01

376

A Gender Recognition System using Shunting Inhibitory Convolutional Neural Networks  

Microsoft Academic Search

In this paper, we employ shunting inhibitory convolutional neural networks to develop an automatic gender recognition system. The system comprises two modules: a face detector and a gender classifier. The human faces are first detected and localized in the input image. Each detected face is then passed to the gender classifier to determine whether it is a male or female.

Fok Hing Chi Tivive; Abdesselam Bouzerdoum

2006-01-01

377

Acetyl and butyryl cholinesterase inhibitory sesquiterpene lactones from Amberboa ramosa  

PubMed Central

Background Alzheimer’s disease (AD) is characterized by a progressive memory loss that leads to a profound emotional disturbance in later stages. As no safe and effective drug is yet available for the treatment of AD, secondary metabolites from plants may be instrumental in meeting this challenge. Keeping in view this point we evaluated sesquiterpenes of medicinal plant Amberboa ramosa for their cholinesterase inhibitory activity. Results Four sesquiterpene lactones have been isolated from the ethyl acetate soluble fraction of Amberboa ramosa. In which one compound Amberbin C (1) was found to be new while other three Amberin (2), Amberbin A (3), and Amberbin B (4) were previously reported ones. The structures of the isolated compounds were elucidated using different spectroscopic techniques. Isolated compounds were tested for their inhibitory potential against acetyl cholinesterase and butyryl cholinesterase enzymes. All compounds showed excellent inhibitory activities against acetyl cholinesterase and butyryl cholinesterase. Conclusions A new sesquiterpene lactone has been isolated and fully characterized, the sesquiterpene lactones from Amberboa ramosa showed good inhibitory activities against acetyl cholinesterase and butyryl cholinesterase enzymes, this study indicated that sesquiterpene lactone can become interesting lead molecules in drug development against Alzheimer’s disease (AD). PMID:23837557

2013-01-01

378

GABA as an Inhibitory Neurotransmitter in Human Cerebral Cortex  

Microsoft Academic Search

1. The possible role of y-aminobutyric acid (GABA) as an in- hibitory neurotransmitter in the human cerebral cortex was in- vestigated with the use of intracellular recordings from neocorti- cal slices maintained in vitro. 2. Electrical stimulation of afferents to presumed pyramidal cells resulted in an initial excitatory postsynaptic potential (EPSP) followed by fast and slow inhibitory postsynaptic potentials (IPSPs).

DAVID A. MCCORMICK

1989-01-01

379

?-Glucosidase inhibitory hydrolyzable tannins from Eugenia jambolana seeds.  

PubMed

Three new hydrolyzable tannins including two gallotannins, jamutannins A (1) and B (2), and an ellagitannin, iso-oenothein C (3), along with eight known phenolic compounds were isolated from the seeds of Eugenia jambolana fruit. The structures were elucidated on the basis of spectroscopic data analysis. All compounds isolated were evaluated for ?-glucosidase inhibitory effects compared to the clinical drug acarbose. PMID:22867049

Omar, Raed; Li, Liya; Yuan, Tao; Seeram, Navindra P

2012-08-24

380

Discovery of diverse small molecule chemotypes with cell-based PKD1 inhibitory activity.  

PubMed

Protein kinase D (PKD) is a novel family of serine/threonine kinases regulated by diacylglycerol, which is involved in multiple cellular processes and various pathological conditions. The limited number of cell-active, selective inhibitors has historically restricted biochemical and pharmacological studies of PKD. We now markedly expand the PKD1 inhibitory chemotype inventory with eleven additional novel small molecule PKD1 inhibitors derived from our high throughput screening campaigns. The in vitro IC(50)s for these eleven compounds ranged in potency from 0.4 to 6.1 µM with all of the evaluated compounds being competitive with ATP. Three of the inhibitors (CID 1893668, (1Z)-1-(3-ethyl-5-methoxy-1,3-benzothiazol-2-ylidene)propan-2-one; CID 2011756, 5-(3-chlorophenyl)-N-[4-(morpholin-4-ylmethyl)phenyl]furan-2-carboxamide; CID 5389142, (6Z)-6-[4-(3-aminopropylamino)-6-methyl-1H-pyrimidin-2-ylidene]cyclohexa-2,4-dien-1-one) inhibited phorbol ester-induced endogenous PKD1 activation in LNCaP prostate cancer cells in a concentration-dependent manner. The specificity of these compounds for PKD1 inhibitory activity was supported by kinase assay counter screens as well as by bioinformatics searches. Moreover, computational analyses of these novel cell-active PKD1 inhibitors indicated that they were structurally distinct from the previously described cell-active PKD1 inhibitors while computational docking of the new cell-active compounds in a highly conserved ATP-binding cleft suggests opportunities for structural modification. In summary, we have discovered novel PKD1 inhibitors with in vitro and cell-based inhibitory activity, thus successfully expanding the structural diversity of small molecule inhibitors available for this important pharmacological target. PMID:21998636

Sharlow, Elizabeth R; Mustata Wilson, Gabriela; Close, David; Leimgruber, Stephanie; Tandon, Manuj; Reed, Robyn B; Shun, Tong Ying; Wang, Q Jane; Wipf, Peter; Lazo, John S

2011-01-01

381

Inhibitory effects of antiviral compounds on respiratory syncytial virus replication in vitro.  

PubMed Central

We examined the inhibitory effect of 20 antiviral compounds, including ribavirin, on the replication of respiratory syncytial virus in HeLa and HEp-2 cell cultures. Of the compounds studied, pyrazofurin and 3-deazaguanine emerged as more potent inhibitors of respiratory syncytial virus than ribavirin. Based on their inhibitory effect on the cytopathogenicity of respiratory syncytial virus in HeLa cells, the average 50% effective dose of pyrazofurin and 3-deazaguanine for eight strains was 0.07 and 1.65 micrograms/ml, respectively; that of ribavirin was 5.82 micrograms/ml. The cytotoxicity of these compounds for HeLa cells was examined by monitoring the incorporation of radiolabeled uridine into cellular RNA. The selectivity indexes of pyrazofurin and 3-deazaguanine exceeded that of ribavirin by 70- and 11-fold, respectively. Pyrazofurin, 3-deazaguanine, and ribavirin inhibited both viral antigen expression and syncytium formation in HeLa cell cultures, as assessed by an indirect immunofluorescence assay. In these assays, pyrazofurin and 3-deazaguanine again proved more potent than ribavirin. 2,5-Diamidinoindole and carbodine were less potent than ribavirin. Various other compounds, i.e., 3-adenin-9-yl-2-hydroxypropanoic acid isobutyl ester, 3-deazauridine, 3'-C-methyluridine, 5'-deoxy-5-fluorouridine, 5-cyanoimidazole-4-carboxamide, and its ribofuranosyl derivative, did not inhibit the cytopathic effect of the Long strain of respiratory syncytial virus at concentrations greater than or equal to 125 micrograms/ml. Tubercidin, 5-chlorotubercidin, xylotubercidin, neplanocin A, thiosemicarbazone R, and 3-methylquercetine were too toxic to HeLa cells for their inhibitory effects on respiratory syncytial virus to be examined. PMID:3307618

Kawana, F; Shigeta, S; Hosoya, M; Suzuki, H; De Clercq, E

1987-01-01

382

Cytotoxic and melanogenesis-inhibitory activities of limonoids from the leaves of Azadirachta indica (Neem).  

PubMed

Seventeen limonoids (tetranortriterpenoids), 1-17, including three new compounds, i.e., 17-defurano-17-(2,5-dihydro-2-oxofuran-3-yl)-28-deoxonimbolide (14), 17-defurano-17-(2?-2,5-dihydro-2-hydroxy-5-oxofuran-3-yl)-28-deoxonimbolide (15), and 17-defurano-17-(5?-2,5-dihydro-5-hydroxy-2-oxofuran-3-yl)-2',3'-dehydrosalannol (17), were isolated from an EtOH extract of the leaf of neem (Azadirachta indica). The structures of the new compounds were elucidated on the basis of extensive spectroscopic analyses and comparison with literature. Upon evaluation of the cytotoxic activities of these compounds against leukemia (HL60), lung (A549), stomach (AZ521), and breast (SK-BR-3) cancer cell lines, seven compounds, i.e., 1-3, 12, 13, 15, and 16, exhibited potent cytotoxicities with IC50 values in the range of 0.1-9.9??M against one or more cell lines. Among these compounds, cytotoxicity of nimonol (1; IC50 2.8??M) against HL60 cells was demonstrated to be mainly due to the induction of apoptosis by flow cytometry. Western blot analysis suggested that compound 1 induced apoptosis via both the mitochondrial and death receptor-mediated pathways in HL60 cells. In addition, when compounds 1-17 were evaluated for their inhibitory activities against melanogenesis in B16 melanoma cells, induced with ?-melanocyte-stimulating hormone (?-MSH), seven compounds, 1, 2, 4-6, 15, and 16, exhibited inhibitory activities with 31-94% reduction of melanin content at 10??M concentration with no or low toxicity to the cells (82-112% of cell viability at 10??M). All 17 compounds were further evaluated for their inhibitory effects against the Epstein?Barr virus early antigen (EBV-EA) activation induced by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells. PMID:24634075

Takagi, Mio; Tachi, Yosuke; Zhang, Jie; Shinozaki, Takuro; Ishii, Kenta; Kikuchi, Takashi; Ukiya, Motohiko; Banno, Norihiro; Tokuda, Harukuni; Akihisa, Toshihiro

2014-03-01

383

Xanthine oxidase inhibitory activity of the methanolic extracts of selected Jordanian medicinal plants  

PubMed Central

Background: The search for novel xanthine oxidase (XO) inhibitors with a higher therapeutic activity and fewer side effects are desired not only to treat gout but also to combat various other diseases associated with the XO activity. At present, the potential of developing successful natural products for the management of XO-related diseases is still largely unexplored. In the present study, we have screened the methanolic extracts of various Jordanian medicinal plants for their XO inhibitory activities using an optimized protocol. Materials and Methods: The methanolic extracts of 23 medicinal plants, belonging to 12 families, were tested in vitro, at 200 ?g/ml concentrations, for their XO inhibitory potential. The dose-dependent inhibition profiles of the most active plants were further evaluated by estimating the IC50 values of their corresponding extracts. Results: Six plants were found most active (% inhibition more than 39%). These plants are Salvia spinosa L. (IC50 = 53.7 ?g/ml), Anthemis palestina Boiss. (168.0 ?g/ml), Chrysanthemum coronarium L. (199.5 ?g/ml), Achillea biebersteinii Afansiev (360.0 ?g/ml), Rosmarinus officinalis L. (650.0 ?g/ml), and Ginkgo biloba L. (595.8 ?g/ml). Moreover, four more plants, namely Lavandula angustifolia Mill. (28.7% inhibition), Helianthemum ledifolium (L.) Mill. (28.4%), Majorana syriaca (L.) Kostel. (25.1%), and Mentha spicata L. (22.5%) showed a XO inhibitory activity in the range of 22–30%. Conclusion: The study showed that many of the tested plant species are potential sources of natural XO inhibitors that can be developed, upon further investigation, into successful herbal drugs for treatment of gout and other XO-related disorders. PMID:22262935

Hudaib, Mohammad M.; Tawaha, Khaled A.; Mohammad, Mohammad K.; Assaf, Areej M.; Issa, Ala Y.; Alali, Feras Q.; Aburjai, Talal A.; Bustanji, Yasser K.

2011-01-01

384

The Role of Inhibitory Control in Behavioral and Physiological Expressions of Toddler Executive Function  

PubMed Central

Eighty-one toddlers (ranging from 24 to 27 months) participated in a biobehavioral investigation of inhibitory control. Maternal-report measures of inhibitory control were related to laboratory tasks assessing inhibitory abilities under conditions of conflict, delay, and compliance challenge as well as toddler verbal ability. Additionally, unique variance in inhibitory control was explained by task-related changes in brain electrical activity at lateral frontal scalp sites as well as concurrent inhibitory task performance. Implications regarding neural correlates of executive function in early development and a central, organizing role of inhibitory processing in toddlerhood are discussed. PMID:20719337

Morasch, Katherine C.; Bell, Martha Ann

2010-01-01

385

Inhibitory effect of a copper-dipeptide complex on the establishment of a Clostridium perenne strain in the intestinal tract of gnotobiotic mice.  

PubMed Central

A semisynthetic diet fed to axenic mice was found to prevent the establishment of a Clostridium perenne strain in their intestinal tract. This inhibitory effect did not occur when axenic mice were preinoculated with a strain of Clostridium difficile. The inhibitory effect was related to the presence in the intestinal contents of axenic mice of both dietary copper and a dipeptide, aspartic-epsilon-lysine. When C. difficile was inoculated into axenic mice, the dipeptide disappeared from the digesta, and C. perenne became established even in the presence of high concentrations of copper. PMID:4091557

Dubos, F; Pelissier, J P; Andrieux, C; Ducluzeau, R; Raibaud, P

1985-01-01

386

Czech ethanol-free propolis extract displays inhibitory activity against a broad spectrum of bacterial and fungal pathogens.  

PubMed

Propolis acts primarily as a biocide against invasive bacteria and fungi in the hive, suggesting its potential for industrial applications. In food application, propolis is considered as a chemical preservative in meat products, extending shelf life of frozen meat and other food. The mechanism of action is still unclear due to the synergy of multiple compounds contained in propolis and due to parallel targeting of multiple pathways within each affected organism. Here, we examined the antimicrobial properties of dimethylsulfoxide (DMSO) Czech propolis extract. Until recently, DMSO was only rarely used in the propolis studies, although the other solvents tested (mostly ethanol) may significantly affect the observed inhibitory effects, notwithstanding the antimicrobial effects of ethanol itself. Here, we provide results of zone inhibition tests against Aspergillus fumigatus, Microsporum gypseum, Microsporum canis, Candida albicans, Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Enterococcus faecalis. Although we determined inhibitory effects against all the microorganisms tested, the dose-dependent response curves were not similar to each other. While inhibitory effects against C. albicans or S. aureus were strictly dose-dependent, responses of M. gypseum and E. faecalis displayed plateau across the broad range of concentrations tested. Interestingly, response of E. coli revealed the double-peak dose-dependent curve, and responses of M. canis and L. monocytogenes decreased at the highest concentrations tested. Suggested is evaluation of DMSO propolis extracts in experimental treatment of human and veterinary infections, preferably in multitherapy with antibiotics. PMID:23915150

Netíková, Ladislava; Bogusch, Petr; Heneberg, Petr

2013-09-01

387

Diverse models for the prediction of HIV integrase inhibitory activity of substituted quinolone carboxylic acids.  

PubMed

In the present study both classification and correlation techniques of diverse nature were successfully employed for the development of models for the prediction of human immunodeficiency virus (HIV) integrase inhibitory activity using a dataset comprising 50 analogs of quinolone carboxylic acid. The values of various molecular descriptors (MDs) for each analog in the dataset were computed using the MDS V-life science QSAR plus module. The values of other MDs which are not part of MDS V-life science were computed using an in-house computer program. A decision tree (DT) was constructed for the HIV integrase inhibitory activity to determine the importance of MDs. The DT learned the information from the input data with an accuracy of 98% and correctly predicted the cross-validated (10 fold) data with an accuracy of 96%. Three MDs, E-state contribution descriptor (SssOHE), molecular connectivity topochemical index ($\\chi {}^{{\\rm A}} $), and eccentric connectivity topochemical index ($\\xi _{{\\rm C}}^{{\\rm C}} $), were used to develop the models using moving average analysis (MAA). The accuracy of classification of single descriptor based models using MAA was found to vary from a minimum of 96% to a maximum of 98%. The statistical significance of the models was assessed through specificity, sensitivity, overall accuracy, Mathew's correlation coefficient, and intercorrelation analysis. The widely used methods like multiple linear regression, partial least squares, and principal component regression were employed for development of correlation models. The models were generated on a training set of 36 molecules. The models had a correlation coefficient (r(2) ) of 0.86 to 0.92, significant cross validated correlation coefficient (q(2) ) of 0.79 to 0.85, F-test from 63.2 to 93.06, r(2) for external test set (pred_r(2) ) from 0.69, coefficient of correlation of predicted dataset (pred_ r(2) Se) of 0.77, and degree of freedom from 27 to 30. Alignment independent descriptors, SsOHE-index, SaaCHE index, SssCH2, and x?log?P were found to be the most important descriptors for the development of correlation models for the prediction of HIV integrase inhibitory activity. PMID:22945879

Gupta, Monika; Madan, Anil Kumar

2012-12-01

388

Serum and salivary macrophage migration inhibitory factor in patients with oral squamous cell carcinoma  

PubMed Central

The overexpression of macrophage migration inhibitory factor (MIF) has been identified in a variety of tumors and the investigation of its molecular mechanisms in tumor progression is a key topic of research. The present study aimed to investigate MIF as a potential marker for disease control or recurrence, and to assess the association between serum and salivary MIF and the clinicopathological characteristics of patients with oral squamous cell carcinoma (OSCC). Serum and salivary samples were collected prior to and following the surgical treatment of 50 patients with OSCC. MIF concentrations were assessed by enzyme-linked immunosorbent assay and the adopted level of statistical significance was P<0.05. The results revealed that serum MIF concentrations were significantly reduced following tumor resection in OSCC patients. Furthermore, higher preoperative salivary MIF concentrations were observed in patients with larger tumors and in those who succumbed to the disease. In conclusion, high salivary and serological MIF concentrations were identified in patients with OSCC. Nevertheless, only serological MIF concentrations may be considered as a potential marker for the early detection of OSCC recurrence once the salivary levels, prior and following treatment, do not show any significant differences. PMID:25289107

DE SOUZA, MARIANA BARBOSA; CURIONI, OTÁVIO ALBERTO; KANDA, JOSSI LEDO; DE CARVALHO, MARCOS BRASILINO

2014-01-01

389

50 CFR 648.124 - Minimum fish sizes.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Minimum fish sizes. 648.124 Section 648.124...the Scup Fishery § 648.124 Minimum fish sizes. (a) The minimum size...c) The minimum size applies to whole fish or any part of a fish found in...

2010-10-01

390

50 CFR 648.103 - Minimum fish sizes.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Minimum fish sizes. 648.103 Section 648.103...Flounder Fisheries § 648.103 Minimum fish sizes. (a) The minimum size for...minimum sizes in this section apply to whole fish or to any part of a fish found in...

2010-10-01

391

No minimum threshold for ozone-induced changes in soybean canopy fluxes  

Technology Transfer Automated Retrieval System (TEKTRAN)

Tropospheric ozone concentrations [O3] are increasing at rates that exceed any other pollutant. This highly reactive gas drives reductions in plant productivity and canopy water use while also increasing canopy temperature and sensible heat flux. It is not clear whether a minimum threshold of ozone ...

392

Assessing the effectiveness of minimum legal drinking age and zero tolerance laws in the United States  

Microsoft Academic Search

The objective of this research was to determine the extent to which the decline in alcohol-related highway deaths among drivers younger than age 21 years can be attributed to raising the minimum legal drinking age (MLDA) and establishing zero tolerance (0.02% blood alcohol concentration (BAC) limit for drivers younger than age 21 years) laws. Data on all drivers younger than

Robert B. Voas; A. Scott Tippetts; James C. Fell

2003-01-01

393

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

PubMed

Chemical investigation of the rhizomes of Cyperus distans (Cyperaceae) led to the identification of ?-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?ą 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. PMID:24941231

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

394

Cytochrome P450 inhibitory action of Echinacea preparations differs widely and co-varies with alkylamide content.  

PubMed

Echinacea preparations are one of the best selling herbal medicinal products with a well established therapeutic use in the prophylaxis of upper respiratory tract infections. Their consumption is increasing, but information about their ability to inhibit cytochrome P450 enzymes (CYP) is fragmentary. The picture is further complicated by a lack of phytochemical characterization of previously tested preparations. Due to its well characterized immunomodulatory activity, the standardized Swiss registered Echinacea purpurea (L.) Moench Echinaforce extract was selected for detailed study. With the single baculovirus-expressed CYP isoforms 1A2, 2C19, 2D9 and 3A4, inhibitory actions were measured by monitoring fluorescent metabolites derived from enzyme substrates (supersome assay). The Echinaforce extract induced mild inhibition of all these isoforms, with CYP 3A4 being the most, and CYP 2D6 the least sensitive enzyme. To assess whether CYP inhibition might be a general feature of Echinacea preparations, an additional nine commercially available preparations were screened using CYP 3A4. All tested preparations were able to inhibit CYP 3A4, but inhibitory potencies (expressed as median inhibitory concentration, IC50) varied by a factor of 150. The alkylamides are thought to be responsible for the immunomodulatory activity of Echinacea, and so the concentration of 2E,4E,8Z,10E/Z-tetranoic acid isobutylamide (1) and total alkylamide content were determined in all preparations, and the latter was found to be associated with their CYP 3A4 inhibitory potency. The chemically pure alkylamides dodeca-2E,4E,8Z,10E/Z-tetranoic acid isobutylamide (1) and dodeca-2E,4E-dieonoic acid isobutylamide (2) showed inhibitory activity on CYP 2C19, 2D6 and 3A4. However, unlike the Echinaforce extract, the alkylamides did not induce CYP 1A2 inhibition. Thus, other, as yet unidentified constituents also contribute to the overall weak inhibitory effects seen with Echinacea preparations in-vitro. PMID:17430641

Modarai, M; Gertsch, J; Suter, A; Heinrich, M; Kortenkamp, A

2007-04-01

395

Anticipating Cycle 24 Minimum and Its Consequences  

NASA Technical Reports Server (NTRS)

On the basis of the 12-mo moving average of monthly mean sunspot number (R) through November 2006, cycle 23 has persisted for 126 mo, having had a minimum of 8.0 in May 1996, a peak of 120.8 in April 2000, and an ascent duration of 47 mo. In November 2006, the 12-mo moving average of monthly mean sunspot number was 12.7, a value just outside the upper observed envelope of sunspot minimum values for the most recent cycles 16-23 (range 3.4-12.3), but within the 90-percent prediction interval (7.8 +/- 6.7). The first spotless day during the decline of cycle 23 occurred in January 2004, and the first occurrence of 10 or more and 20 or more spotless days was February 2006 and April 2007, respectively, inferring that sunspot minimum for cycle 24 is imminent. Through May 2007, 121 spotless days have accumulated. In terms of the weighted mean latitude (weighed by spot area) (LAT) and the highest observed latitude spot (HLS) in November 2006, 12-mo moving averages of these parameters measured 7.9 and 14.6 deg, respectively, these values being the lowest values yet observed during the decline of cycle 23 and being below corresponding mean values found for cycles 16-23. As yet, no high-latitude new-cycle spots have been seen nor has there been an upturn in LAT and HLS, these conditions having always preceded new cycle minimum by several months for past cycles. Together, these findings suggest that cycle 24 s minimum amplitude still lies well beyond November 2006. This implies that cycle 23 s period either will lie in the period "gap" (127-134 mo), a first for a sunspot cycle, or it will be longer than 134 mo, thus making cycle 23 a long-period cycle (like cycle 20) and indicating that cycle 24 s minimum will occur after July 2007. Should cycle 23 prove to be a cycle of longer period, a consequence might be that the maximum amplitude for cycle 24 may be smaller than previously predicted.

Wilson, Robert M.; Hathaway, David H.

2007-01-01

396

BME ERGONOMICS AND REHABILITATION ENGINEERING CONCENTRATION1  

E-print Network

BME ERGONOMICS AND REHABILITATION ENGINEERING CONCENTRATION1 ­ F10 MS: 30 total credit hours minimum Advisor: Thomas J. Armstrong, Ph.D. (tja@umich.edu) Ergonomics /Rehabilitation Engineering: IOE 463 Measurement and Design of Work (3) (I, II) (Prerequisite: IOE 333 Ergonomics) BIOMED E 534

Eustice, Ryan

397

Acetylcholinesterase enzyme inhibitory potential of standardized extract of Trigonella foenum graecum L and its constituents.  

PubMed

Ethno pharmacological approach has provided several leads to identify potential new drugs from plant sources, including those for memory disorders. Acetylcholinesterase inhibitors (AChEI) give a symptomatic relief to some of the clinical manifestations of the disease. The main objective of this study is to standardize the extract of Trigonella foenum graecum L with trigonelline by HPTLC method and determine the in vitro AChE inhibitory activity of Trigonella foenum graecum L and its constituents using galanthamine as a reference. Different concentrations of hydro alcoholic extract of Trigonella foenum graecum and trigonelline were subjected to HPTLC analysis using the mobile phase n propanol, methanol and water (4:1:2, v/v). The R(f) of trigonelline was found to be 0.43, and the correlation coefficient of 0.99 was indicative of good linear dependence of peak area on concentration. The concentration of trigonelline was found to be 13mgg(-1)w/w in the hydro alcoholic extract of Trigonella foenum graecum. The AChE inhibitory activity of crude fenugreek seed extracts, fractions and trigonelline was evaluated using Ellman's method in 96-well micro plate's assay and TLC bioassay detection. The ethyl acetate fraction of the alcohol extract (IC50 53.00 +/- 17.33microg/ml), and total alkaloid fraction (IC50 9.23+/-6.08microg/ml) showed potential AChE inhibition. Trigonelline showed IC50 233+/-0.12microM. Galanthamine was used as standard and it showed inhibition of acetyl cholinesterase with an IC50 value of 1.27+/-0.21microM. PMID:19576740

Satheeshkumar, N; Mukherjee, Pulok K; Bhadra, S; Saha, B P

2010-03-01

398

Inhibitory effect of Zataria multiflora Boiss and carvacrol on histamine (H(1) ) receptors of guinea-pig tracheal chains.  

PubMed

The inhibitory effect of aqueous-ethanolic extract of Zataria multiflora Boiss (Labiatae) and carvacrol on histamine (H(1) ) receptors was examined on tracheal chains of guinea-pigs. The effects of three concentrations of aqueous-ethanolic extract, carvacrol, 10 nm chlorpheniramine, and saline on histamine (H(1) ) receptors were tested on three groups of guinea-pig tracheal chains as follows: incubated trachea with (i) indomethacin (n = 9), (ii) indomethacin, propranolol, and atropine (n = 7), and (iii) indomethacin and propranolol (n = 6). The EC(50) (effective concentration of histamine causing 50% of maximum response) obtained in the presence of chlorpheniramine for all concentrations of the extract and carvacrol in all three groups was significantly higher than that of saline (P < 0.001 for all cases). The EC(50) obtained in the presence of all concentrations of extract in groups 2 and 3 was lower than group 1 and in group 3 lower than group 2 (P < 0.01 to P < 0.001). However, EC(50) obtained in the presence of all concentrations of carvacrol in group 3 and two higher concentrations in group 2 was higher than that of group 1 (P < 0.01 to P < 0.001). There was no significant difference in the maximum response obtained in the presence of different concentrations of extract and carvacrol between three groups. There was a parallel rightward shift in concentration-response curves obtained in the presence of all concentrations of the extract and carvacrol in all three groups. These results indicated an inhibitory effect of Z. multiflora and its constituent carvacrol on histamine H(1) receptors. PMID:21806678

Boskabady, Mohammad Hossein; Tabanfar, Hengameh; Gholamnezhad, Zahra; Sadeghnia, Hamid Reza

2012-10-01

399

The Inhibitory Effect of Grasshopper’s Cyperus (Cyperus iria L.) on the Seedling Growth of Five Malaysian Rice Varieties  

PubMed Central

Experiments were carried out in the laboratory and greenhouse to determine the growth inhibitory effects of Grassohopper’s cyperus (Cyperus iria L.) on the seedlings of 5 Malaysian rice varieties namely MR211, MRQ74, MR220, MR84 and MR232. Three concentrations of the aqueous extract of the weed (12.5, 25.0 and 50.0 g/l) and weed debris (5, 10 and 20 g dry debris/1000 g soil) were used to test the allelopathic effect of C. iria on the growth of the rice plants. The weed leaf, stem and root extracts reduced the growth of the rice seedlings and showed selective activity in the varieties. The C. iria leaf and stem extracts showed comparatively higher growth inhibitory effects than those from the root. The weed extract caused more reduction in the root length of the rice plant compared to the shoot length. Among the rice varieties tested, MR232 was found to be more susceptible to the weed inhibitory effect. The leaf extract of C. iria at full strength caused root and shoot reduction of MR232 by 88.1% and 73.1% respectively (compared to the control). In most cases the fresh weight of the rice seedlings were more affected than the plant height. Weed debris caused significant reduction of leaf chlorophyll content in all the rice varieties tested with the exception of MR211. The chlorophyll content of MR232 was greatly affected by the weed debris which caused reduction of 36.4% compared to the control. The inhibitory effects of weed extracts and debris on rice growth parameters were found to be concentration dependent. PMID:24575211

Ismail, B. S.; Siddique, Mohammed Abu Bakar

2011-01-01

400

In vitro xanthine oxidase inhibitory and in vivo hypouricemic activity of herbal coded formulation (Gouticin).  

PubMed

Currently, natural products have been used in treating gouty arthritis and are recognized as xanthine oxidase inhibitors. Current study was designed to evaluate in vitro xanthine oxidase inhibitory potential of Gouticin and its ingredients extracts and in vivo hypouricemic activity of gouticin tablet 500 mg twice daily. Ethanol extracts of Gouticin and its ingredients were evaluated in vitro, at 200, 100, 50, 25 ? g/ml concentrations for xanthine oxidase inhibitory activity. IC(50) values of Gouticin and its ingredients were estimated. Further, in vivo therapeutic effect of Gouticin was investigated in comparison with allopathic medicine (Allopurinol) to treat gout. Total patients were 200 that were divided into test and control group. Herbal coded medicine (Gouticin) was given to test group and allopathic medicine allopurinol was administered to control group. In vitro, Gouticin has the highest percent inhibition at 96% followed by Allopurinol with 93% inhibition. In vivo study, mean serum uric acid level of patients was 4.62 mg/dl and 5.21mg/dl by use of Gouticin and Allopurinol at end of therapy. The study showed that herbal coded formulation gouticin and its ingredients are potential sources of natural xanthine oxidase inhibitors. Gouticin 500 mg twice daily is more effective than the allopurinol 300mg once daily in the management of gout. PMID:24811815

Akram, Muhammad; Usmanghani, Khan; Ahmed, Iqbal; Azhar, Iqbal; Hamid, Abdul

2014-05-01

401

Inhibitory effect of gold nanoparticles on the D-ribose glycation of bovine serum albumin.  

PubMed

Formation of advanced glycation end products (AGEs) by nonenzymatic glycation of proteins is a major contributory factor to the pathophysiology of diabetic conditions including senile dementia and atherosclerosis. This study describes the inhibitory effect of gold nanoparticles (GNPs) on the D-ribose glycation of bovine serum albumin (BSA). A combination of analytical methods including ultraviolet-visible spectrometry, high performance liquid chromatography, circular dichroism, and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry were used to determine the extent of BSA glycation in the presence of citrate reduced spherical GNPs of various sizes and concentrations. GNPs of particle diameters ranging from 2 nm to 20 nm inhibited BSA's AGE formation. The extent of inhibition correlated with the total surface area of the nanoparticles. GNPs of highest total surface area yielded the most inhibition whereas those with the lowest total surface area inhibited the formation of AGEs the least. Additionally, when GNPs' total surface areas were set the same, their antiglycation activities were similar. This inhibitory effect of GNPs on BSA's glycation by D-ribose suggests that colloidal particles may have a therapeutic application for the treatment of diabetes and conditions that promote hyperglycemia. PMID:25473284

Liu, Weixi; Cohenford, Menashi A; Frost, Leslie; Seneviratne, Champika; Dain, Joel A

2014-01-01

402

Inhibitory Effect of Arctigenin from Fructus Arctii Extract on Melanin Synthesis via Repression of Tyrosinase Expression  

PubMed Central

To identify the active compound arctigenin in Fructus Arctii (dried seed of medicinal plant Arctium lappa) and to elucidate the inhibitory mechanism in melanogenesis, we analyzed melanin content and tyrosinase activity on B16BL6 murine melanoma and melan-A cell cultures. Water extracts of Fructus Arctii were shown to inhibit tyrosinase activity in vitro and melanin content in ?-melanocyte stimulating hormone-stimulated cells to similar levels as the well-known kojic acid and arbutin, respectively. The active compound arctigenin of Fructus Arctii displayed little or no cytotoxicity at all concentrations examined and decreased the relative melanin content and tyrosinase activity in a dose-dependent manner. Melanogenic inhibitory activity was also identified in vivo with zebrafish embryo. To determine the mechanism of inhibition, the effects of arctigenin on tyrosinase gene expression and tyrosinase promoter activity were examined. Also in addition, in the signaling cascade, arctigenin dose dependently decreased the cAMP level and promoted the phosphorylation of extracellular signal-regulated kinase. This result suggests that arctigenin downregulates cAMP and the tyrosinase enzyme through its gene promoter and subsequently upregulates extracellular signal-regulated kinase activity by increasing phosphorylation in the melanogenesis signaling pathway, which leads to a lower melanin content. PMID:23781272

Park, Hwayong; Song, Kwang Hoon; Jung, Pil Mun; Kim, Ji-Eun; Kim, Mi Yoon; Ma, Jin Yeul

2013-01-01

403

Growth inhibitory effects of bovine lactoferrin to Toxoplasma gondii parasites in murine somatic cells.  

PubMed

Lactoferrin (LF) is known to have broad spectrum antimicrobial properties. In regards to its defense mechanism against parasitic infection, it has shown phagocytic activity in the destruction of amastigotes, an intracellular parasitic form of Trypanosoma cruzi in macrophages. The effect of bovine lactoferrin on the intracellular growth Toxoplasma gondii parasites was examined in murine macrophage and embryonal cells. Co-cultures of host cells with the parasites were supplemented with either lactoferrin, apo-lactoferrin, holo-lactoferrin or transferrin in the culture media for varying periods. The growth activity of intracellular parasites in the host cells was determined by the measurement of selective incorporation of 3H-uracil. Supplement of lactoferrin had no effect on the penetration activity of the parasites, while development of intracellular parasites was inhibited linearly in concentration of lactoferrin. Supplement of apo-lactoferrin and holo-lactoferrin, but not transferrin showed similar effects. These suggest that lactoferrin induces the inhibitory effects on the development of intracellular parasites. Pretreatment of lactoferrin to the macrophages, however, did not show any inhibitory effects. Whereas, mouse embryonal cells preincubated with lactoferrin suppressed the intracellular growth. Thus, the action of lactoferrin to macrophages would be different from that of mouse embryonal cells. PMID:8645758

Tanaka, T; Omata, Y; Saito, A; Shimazaki, K; Igarashi, I; Suzuki, N

1996-01-01

404

Thailandepsins: Bacterial Products with Potent Histone Deacetylase Inhibitory Activities and Broad-Spectrum Antiproliferative Activities  

PubMed Central

Histone deacetylase (HDAC) inhibitors have emerged as a new class of anticancer drugs, with one synthetic compound, SAHA (vorinostat, Zolinza®; 1), and one natural product, FK228 (depsipeptide, romidepsin, Istodax®; 2), approved by FDA for clinical use. Our studies of FK228 biosynthesis in Chromobacterium violaceum No. 968 led to the identification of a cryptic biosynthetic gene cluster in the genome of Burkholderia thailandensis E264. Genome mining and genetic manipulation of this gene cluster further led to the discovery of two new products, thailandepsin A (6) and thailandepsin B (7). HDAC inhibition assays showed that thailandepsins have selective inhibition profiles different from that of FK228, with comparable inhibitory activities to those of FK228 toward human HDAC1, HDAC2, HDAC3, HDAC6, HDAC7 and HDAC9, but weaker inhibitory activities than FK228 toward HDAC4 and HDAC8, the later of which could be beneficial. NCI-60 anticancer screening assays showed that thailandepsins possess broad-spectrum antiproliferative activities with GI50 for over 90% of the tested cell lines at low nanomolar concentrations, and potent cytotoxic activities towards certain types of cell lines, particularly for those derived from colon, melanoma, ovarian and renal cancers. Thailandepsins thus represent new naturally produced HDAC inhibitors that are promising for anticancer drug development. PMID:21793558

Wang, Cheng; Henkes, Leonhard M.; Doughty, Leah B.; He, Min; Wang, Difei; Meyer-Almes, Franz-Josef; Cheng, Yi-Qiang

2011-01-01

405

Glutathione peroxidase inhibitory assay for electrophilic pollutants in diesel exhaust and tobacco smoke  

PubMed Central

We developed a rapid kinetic bioassay demonstrating the inhibition of glutathione peroxidase 1 (GPx-1) by organic electrophilic pollutants such as acrolein, crotonaldehyde, and p-benzoquinone that are frequently found as components of tobacco smoke, diesel exhaust, and other combustion sources. In a complementary approach, we applied a high-resolution proton-transfer reaction time-of-flight mass spectrometer (PTR-ToF-MS) to monitor in real-time the generation of electrophilic volatile carbonyls in cigarette smoke. The new bioassay uses the important antioxidant selenoenzyme GPx-1, immobilized to 96-well microtiter plates, as a probe. The selenocysteine bearing subunits of the enzyme's catalytic site are viewed as cysteine analogues and are vulnerable to electrophilic attack by compounds with conjugated carbonyl systems. The immobilization of GPx-1 to microtiter plate wells enabled facile removal of excess reactive inhibitory compounds after incubation with electrophilic chemicals or aqueous extracts of air samples derived from different sources. The inhibitory response of cigarette smoke and diesel exhaust particle extracts were compared to chemical standards of a group of electrophilic carbonyls and the arylating p-benzoquinone. GPx-1 activity was directly inactivated by millimolar concentrations of highly reactive electrophilic chemicals (including acrolein, glyoxal, methylglyoxal, and p-benzoquinone) and extracts of diesel and cigarette smoke. We conclude that the potential of air pollutant components to generate oxidative stress may be, in part, a result of electrophile-derived covalent modifications of enzymes involved in the cytosolic antioxidant defense. PMID:22349402

Staimer, Norbert; Nguyen, Tran B.; Nizkorodov, Sergey A.; Delfino, Ralph J.

2012-01-01

406

Inhibitory effects of Alpinia speciosa K. SCHUM on the porphyrin photooxidative reaction.  

PubMed

It is thought that the beta-carotene defense mechanism against photosensitivity involves the inhibition of singlet oxygen formation, a kind of active oxygen. When we screened chemical substances obtained from plants indigenous to Okinawa, known to have residents with the longest life span in Japan, we found that Alpinia speciosa K. SCHUM (Japanese name: gettou), which is used as a food preservative, has an activity similar to that of beta-carotene. We measured the amount of lipid peroxide (LPO) formed from a hematoporphyrin-containing rat liver microsomal suspension irradiated with visible light. The inhibitory effect of Alpinia speciosa on LPO formation was confirmed when the addition of increasing concentrations of Alpinia speciosa extract led to a decrease in the amount of LPO formed. Moreover, the reaction mechanism that affects the amount of singlet oxygen formed was measured, and the effect of the extract was determined by the ESR trapping technique. It was found that the extract effectively inhibited the formation of singlet oxygen. The extract of Alpinia speciosa contains dihydro-5,6-dehydrokawain. It was confirmed that dihydro-5,6-dehydrokawain, which is a water-soluble compound, has singlet oxygen quenching activity. We synthesized five derivatives of kawain and found that dimethyl [6-(2-phenylethyl)-2-oxo-2H-pyran-4-yl] phosphorothionate has the strongest singlet oxygen quenching activity. The use of the compound from Alpinia speciosa that exhibits singlet oxygen quenching activity as an inhibitory agent of the phototoxic reaction in porphyria is expected. PMID:10875197

Liao, M C; Arakaki, H; Li, Y; Takamiyagi, A; Tawata, S; Aniya, Y; Sakurai, H; Nonaka, S

2000-05-01

407

Evaluation of the RNase H Inhibitory Properties of Vietnamese Medicinal Plant Extracts and Natural Compounds  

PubMed Central

In research on anti-human immunodeficiency virus (HIV) agents from natural sources, thirty two extracts of Vietnamese plants and twenty five isolated compounds were screened for their inhibitory effect against the ribonuclease H (RNase H) activity of HIV-1 reverse transcriptase and the cytopathic effect of the HIV virus. At a concentration of 50 ?g/mL, eleven plant extracts and five isolated compounds inhibited over 90 percent of RNase H enzymatic activity. Of these, the methanol extracts from the leaves of Phyllanthus reticulatus and Aglaia aphanamixis highly inhibited RNase H activity by 99% and 98%, respectively. Several fucoidans isolated from seaweeds Sargassum kuetzingii, Sargassum polycystum, and Gelidiella acerosa, as well as epigallocatechin-3-gallate isolated from Camellia chinensis also showed strong inhibitory effects over ninety percent. Sixteen plant extracts with inhibition of over seventy five percent in the RNase H assay were tested in a cellular model of HIV-1 cytopathicity; four extracts showed modest activity in protecting against the cytopathic effect of the HIV virus. PMID:21595586

Tai, Bui Huu; Nhut, Nguyen Duy; Nhiem, Nguyen Xuan; Tung, Nguyen Huu; Quang, Tran Hong; Luyen, Bui Thi Thuy; Huong, Tran Thu; Wilson, Jennifer; Beutler, John A.; Cuong, Nguyen Manh; Kim, Young Ho

2013-01-01

408

Inhibitory effects of cationic hybrid liposomes on the growth of human renal cell carcinoma.  

PubMed

Cationic hybrid liposomes (HL) can be prepared by simply ultrasonicating a mixture of L-alpha-dimyristoylphosphatidylcholine (DMPC), polyoxyethylene (21)dodecyl ether (C(12)(EO)(21)) and O,O'-ditetradecanoyl-N-(alpha-trimethylammonioacetyl) diethanolamine chloride (2C(14)ECl) in a buffer solution. The inhibitory effects of cationic HL containing 2C(14)ECl on the growth of OS-RC-2 human renal carcinoma cells in vitro and in vivo were examined. The 50% inhibitory concentration of cationic HL was remarkably reduced compared with that of DMPC liposomes. Induction of apoptosis by cationic HL in OS-RC-2 cells was verified on the basis of flow cytometric analysis and fluorescence microscopy in vitro. In addition, the effects on survival of cationic HL along with apoptosis in vivo were obtained using a mouse model of renal carcinoma. Chemotherapy with drug-free cationic HL for renal cell carcinoma was developed for the first time through the interaction between cationic HL and anionic surface region of tumor cell membranes, without any side-effects. The results obtained might be applied in chemotherapies used at present for patients with renal carcinoma. PMID:20332436

Umebayashi, Masayo; Makizono, Taku; Ichihara, Hideaki; Matsumoto, Yoko; Ueoka, Ryuichi

2010-02-01

409

Glycine transporter-1 controls nonsynaptic inhibitory actions of glycine receptors in the neonatal rat hippocampus.  

PubMed

Although functional glycinergic synapses have not been identified in the hippocampus, neurons in this area express Cl(-) permeable extrasynaptic glycine receptors (GlyRs). In experiments on CA3 pyramidal neurons on postnatal day 0-6 rat hippocampal slices, we detected robust GlyR activity as a tonic current and as single-channel events. Glycine release was independent of neuronal activity or extracellular Ca(2+). The endogenous GlyR activity was strongly enhanced by inhibition of the glycine-transporter-1 (GlyT1). Blockade of GlyT1 also caused a profound increase in the baseline current induced by exogenous glycine. Inhibition of GlyT1 reduced the frequency of spontaneous network events known as field giant depolarizing potentials (fGDPs) and of the unit activity in the absence of synaptic transmission. This inhibitory action on fGDPs was mimicked by applying 2 ?m glycine or 0.1 ?m isoguvacine, a GABAA-receptor agonist. Furthermore, 2 ?m glycine suppressed unit spiking in the absence of synaptic transmission. Hence, despite the well known depolarizing Cl(-) equilibrium potential of neonatal hippocampal neurons, physiologically relevant extracellular glycine concentrations can exert an inhibitory action. The present data show that, akin to GABA uptake, GlyT1 exerts a powerful modulatory action on network events in the newborn hippocampus. PMID:25057202

Sipilä, Sampsa T; Spoljaric, Albert; Virtanen, Mari A; Hiironniemi, Inkeri; Kaila, Kai

2014-07-23

410

Inhibitory Effect of Arctigenin from Fructus Arctii Extract on Melanin Synthesis via Repression of Tyrosinase Expression.  

PubMed

To identify the active compound arctigenin in Fructus Arctii (dried seed of medicinal plant Arctium lappa) and to elucidate the inhibitory mechanism in melanogenesis, we analyzed melanin content and tyrosinase activity on B16BL6 murine melanoma and melan-A cell cultures. Water extracts of Fructus Arctii were shown to inhibit tyrosinase activity in vitro and melanin content in ? -melanocyte stimulating hormone-stimulated cells to similar levels as the well-known kojic acid and arbutin, respectively. The active compound arctigenin of Fructus Arctii displayed little or no cytotoxicity at all concentrations examined and decreased the relative melanin content and tyrosinase activity in a dose-dependent manner. Melanogenic inhibitory activity was also identified in vivo with zebrafish embryo. To determine the mechanism of inhibition, the effects of arctigenin on tyrosinase gene expression and tyrosinase promoter activity were examined. Also in addition, in the signaling cascade, arctigenin dose dependently decreased the cAMP level and promoted the phosphorylation of extracellular signal-regulated kinase. This result suggests that arctigenin downregulates cAMP and the tyrosinase enzyme through its gene promoter and subsequently upregulates extracellular signal-regulated kinase activity by increasing phosphorylation in the melanogenesis signaling pathway, which leads to a lower melanin content. PMID:23781272

Park, Hwayong; Song, Kwang Hoon; Jung, Pil Mun; Kim, Ji-Eun; Ro, Hyunju; Kim, Mi Yoon; Ma, Jin Yeul

2013-01-01

411

Autocorrelation of rainfall and streamflow minimums  

USGS Publications Warehouse

Hydrologic time series of annual minimum mean monthly rainfall and annual minimum 1-day and 7-day discharge, considered as drought indices, were used to study the distribution of droughts with respect to time. The rainfall data were found to be nearly random. The discharge data, however, were found to be nonrandomly distributed in time and generated by a first-order Markov process. The expected value of the variance for a time series generated by a first-order Markov process was compared with the expected value of the variance for a random time series. This comparison showed that the expected value of the variance for a nonrandom time series converged to the population variance with an increase in sample size at a slower rate than for a random time series.

Matalas, N.C.

1963-01-01

412

On finding minimum-diameter clique trees  

SciTech Connect

It is well-known that any chordal graph can be represented as a clique tree (acyclic hypergraph, join tree). Since some chordal graphs have many distinct clique tree representations, it is interesting to consider which one is most desirable under various circumstances. A clique tree of minimum diameter (or height) is sometimes a natural candidate when choosing clique trees to be processed in a parallel computing environment. This paper introduces a linear time algorithm for computing a minimum-diameter clique tree. The new algorithm is an analogue of the natural greedy algorithm for rooting an ordinary tree in order to minimize its height. It has potential application in the development of parallel algorithms for both knowledge-based systems and the solution of sparse linear systems of equations. 31 refs., 7 figs.

Blair, J.R.S. (Tennessee Univ., Knoxville, TN (United States). Dept. of Computer Science); Peyton, B.W. (Oak Ridge National Lab., TN (United States))

1991-08-01

413

Minimum wakefield achievable by waveguide damped cavity  

SciTech Connect

The authors use an equivalent circuit to model a waveguide damped cavity. Both exponentially damped and persistent (decay t{sup {minus}3/2}) components of the wakefield are derived from this model. The result shows that for a cavity with resonant frequency a fixed interval above waveguide cutoff, the persistent wakefield amplitude is inversely proportional to the external Q value of the damped mode. The competition of the two terms results in an optimal Q value, which gives a minimum wakefield as a function of the distance behind the source particle. The minimum wakefield increases when the resonant frequency approaches the waveguide cutoff. The results agree very well with computer simulation on a real cavity-waveguide system.

Lin, X.E.; Kroll, N.M.

1995-05-01

414

Minimum and terminal velocities in projectile motion  

E-print Network

The motion of a projectile with horizontal initial velocity V0, moving under the action of the gravitational field and a drag force is studied analytically. As it is well known, the projectile reaches a terminal velocity Vterm. There is a curious result concerning the minimum speed Vmin; it turns out that the minimum velocity is lower than the terminal one if V0 > Vterm and is lower than the initial one if V0 velocity is not a monotonous function. If the initial speed is not horizontal, there is an angle range where the velocity shows the same behavior mentioned previously. Out of that range, the volocity is a monotonous function. These results come out from numerical simulations.

Miranda, E N; Riba, R

2012-01-01

415

Minimum and terminal velocities in projectile motion  

E-print Network

The motion of a projectile with horizontal initial velocity V0, moving under the action of the gravitational field and a drag force is studied analytically. As it is well known, the projectile reaches a terminal velocity Vterm. There is a curious result concerning the minimum speed Vmin; it turns out that the minimum velocity is lower than the terminal one if V0 > Vterm and is lower than the initial one if V0 velocity is not a monotonous function. If the initial speed is not horizontal, there is an angle range where the velocity shows the same behavior mentioned previously. Out of that range, the volocity is a monotonous function. These results come out from numerical simulations.

E. N. Miranda; S. Nikolskaya; R. Riba

2012-08-13

416

Minimum correlation in construction of multivariate distributions  

NASA Astrophysics Data System (ADS)

In this paper we present an algorithm for exact generation of multivariate samples with prespecified marginal distributions and a given correlation matrix, based on a mixture of Fréchet-Hoeffding bounds and marginal products. In the bivariate case, the algorithm can accommodate any among the theoretically possible correlation coefficients, and explicitly provides a connection between simulation and the minimum correlation attainable for different distribution families. We calculate the minimum correlations in several common distributional examples, including in some that have not been looked at before. As an illustration, we provide the details and results of implementing the algorithm for generating three-dimensional negatively and positively correlated Beta random variables, making it the only noncopula algorithm for correlated Beta simulation in dimensions greater than two. This work has potential for impact in a variety of fields where simulation of multivariate stochastic components is desired.

Dukic, Vanja M.; Mari?, Nevena

2013-03-01

417

Effect of low static nitrate concentrations on mineral nitrogen uptake, nodulation, and nitrogen fixation in field pea  

Microsoft Academic Search

Combined nitrogen [nitrate (NO3?), ammonium (NH4+), and urea] will inhibit all components of symbiotic nitrogen (N2) fixation if present in sufficient concentrations. It is generally accepted that nitrate is particularly inhibitory to nodule growth and nitrogenase activity, and somewhat less inhibitory to the infection process. This project examined whether providing low (0.1 ? 0.5 mM) static concentrations of NO3? to

John G. Waterer; J. Kevin Vessey

1993-01-01

418

Minimum cycle bases: Faster and simpler  

Microsoft Academic Search

We consider the problem of computing exact or approximate minimum cycle bases of an undirected (or directed) edge-weighted graph G with m edges and n vertices. In this problem, a f0; 1g (fˇ1; 0; 1g) incidence vector is associated with each cycle and the vector space over F2 (Q) generated by these vectors is the cycle space of G. A

Kurt Mehlhorn; Dimitrios Michail

2009-01-01

419

Scheduling a minimum dependence in FSMs  

Microsoft Academic Search

We present a scheduling algorithm for controllers which reduces cycle time in datapath-controller systems. The algorithm chooses a schedule to reduce the primary outputs’ dependence on late-arriving inputs– a minimum-dependence structure leads to a shorter system cycle time. Our algorithm accurately predicts from a behavioral description FSM properties which are correlated with fast logic. Experimental results show that the algorithm

Steve C.-Y. Huang; Wayne H. Wolf

1993-01-01

420

Scheduling for minimum dependence in FSMs  

Microsoft Academic Search

We present a scheduling algorithm for controllers which reduces cycle time in datapath-controller systems. The algorithm chooses a schedule to reduce the primary output's dependence on late-arriving inputs - a minimum-dependence structure leads to a shorter system cycle time. Our algorithm accurately predicts from a behavioral description FSM properties which are correlated with fast logic. Experimental results show that the

S. C.-Y. Huang; W. H. Wolf

1993-01-01

421

Performance analysis of the minimum variance beamformer  

Microsoft Academic Search

We present an analysis of the signal-to-interference-plus-noise ratio (SINR) at the output of the minimum variance beamformer. The analysis is based on the assumption that the signals and noise are Gaussian and that the number of samples is large compared to the array size, and it yields an explicit expression for the SINR in terms of the different parameters affecting

Mati Wax; Yosef Anu

1996-01-01

422

Solar Modulation along last solar minimum  

NASA Astrophysics Data System (ADS)

The effects of cosmic rays modulation on proton spectrum was studied using the HelMod - 2-D Monte Carlo code, that includes a general description of the diffusion tensor, and polar magnetic-field. The Numerical Approach used in this work is based on a set of Stochastic Differential Equations fully equivalent to the well know Parker Equation for the transport of Cosmic Rays. The model description was updated using Proton spectras measured by PAMELA during the last solar minimum.

Bobik, P.; Boschini, M. J.; Delia Torre, S.; Gervasi, M.; Grandi, D.; Kudela, K.; La Vacca, G.; Mallamaci, M.; Pensotti, S.; Rancoita, P. G.; Rozza, D.; Tacconi, M.

2014-06-01

423

Minimum concave cost multicommodity network design  

Microsoft Academic Search

The minimum concave cost multicommodity network design problem (MCMNDP) arises in many application areas, such as transportation\\u000a planning, energy distribution systems and especially in the design of both packet and circuit switching backbone networks.\\u000a Exact concave cost optimization algorithms have been developed but they are applicable only if the network size is small.\\u000a Therefore, MCMNDP is usually solved using non-exact

Cüneyt F. Bazlamaçci; Fatih Say

2007-01-01

424

Design for minimum energy in interstellar communication  

NASA Astrophysics Data System (ADS)

Microwave digital communication at interstellar distances is the foundation of extraterrestrial civilization (SETI and METI) communication of information-bearing signals. Large distances demand large transmitted power and/or large antennas, while the propagation is transparent over a wide bandwidth. Recognizing a fundamental tradeoff, reduced energy delivered to the receiver at the expense of wide bandwidth (the opposite of terrestrial objectives) is advantageous. Wide bandwidth also results in simpler design and implementation, allowing circumvention of dispersion and scattering arising in the interstellar medium and motion effects and obviating any related processing. The minimum energy delivered to the receiver per bit of information is determined by cosmic microwave background alone. By mapping a single bit onto a carrier burst, the Morse code invented for the telegraph in 1836 comes closer to this minimum energy than approaches used in modern terrestrial radio. Rather than the terrestrial approach of adding phases and amplitudes increases information capacity while minimizing bandwidth, adding multiple time-frequency locations for carrier bursts increases capacity while minimizing energy per information bit. The resulting location code is simple and yet can approach the minimum energy as bandwidth is expanded. It is consistent with easy discovery, since carrier bursts are energetic and straightforward modifications to post-detection pattern recognition can identify burst patterns. Time and frequency coherence constraints leading to simple signal discovery are addressed, and observations of the interstellar medium by transmitter and receiver constrain the burst parameters and limit the search scope.

Messerschmitt, David G.

2015-02-01

425

Minimum Contradiction Matrices in Whole Genome Phylogenies  

PubMed Central

Minimum contradiction matrices are a useful complement to distance-based phylogenies. A minimum contradiction matrix represents phylogenetic information under the form of an ordered distance matrix Yi, jn. A matrix element corresponds to the distance from a reference vertex n to the path (i, j). For an X-tree or a split network, the minimum contradiction matrix is a Robinson matrix. It therefore fulfills all the inequalities defining perfect order: Yi, jn ? Yi,kn, Yk jn ? Yk, In, i ? j ? k < n. In real phylogenetic data, some taxa may contradict the inequalities for perfect order. Contradictions to perfect order correspond to deviations from a tree or from a split network topology. Efficient algorithms that search for the best order are presented and tested on whole genome phylogenies with 184 taxa including many Bacteria, Archaea and Eukaryota. After optimization, taxa are classified in their correct domain and phyla. Several significant deviations from perfect order correspond to well-documented evolutionary events. PMID:19204821

Thuillard, Marc

2008-01-01

426

On the Minimum Induced Drag of Wings  

NASA Technical Reports Server (NTRS)

Of all the types of drag, induced drag is associated with the creation and generation of lift over wings. Induced drag is directly driven by the span load that the aircraft is flying at. The tools by which to calculate and predict induced drag we use were created by Ludwig Prandtl in 1903. Within a decade after Prandtl created a tool for calculating induced drag, Prandtl and his students had optimized the problem to solve the minimum induced drag for a wing of a given span, formalized and written about in 1920. This solution is quoted in textbooks extensively today. Prandtl did not stop with this first solution, and came to a dramatically different solution in 1932. Subsequent development of this 1932 solution solves several aeronautics design difficulties simultaneously, including maximum performance, minimum structure, minimum drag loss due to control input, and solution to adverse yaw without a vertical tail. This presentation lists that solution by Prandtl, and the refinements by Horten, Jones, Kline, Viswanathan, and Whitcomb

Bowers, Albion H.

2010-01-01

427

On the Minimum Induced Drag of Wings  

NASA Technical Reports Server (NTRS)

Of all the types of drag, induced drag is associated with the creation and generation of lift over wings. Induced drag is directly driven by the span load that the aircraft is flying at. The tools by which to calculate and predict induced drag we use were created by Ludwig Prandtl in 1903. Within a decade after Prandtl created a tool for calculating induced drag, Prandtl and his students had optimized the problem to solve the minimum induced drag for a wing of a given span, formalized and written about in 1920. This solution is quoted in textbooks extensively today. Prandtl did not stop with this first solution, and came to a dramatically different solution in 1932. Subsequent development of this 1932 solution solves several aeronautics design difficulties simultaneously, including maximum performance, minimum structure, minimum drag loss due to control input, and solution to adverse yaw without a vertical tail. This presentation lists that solution by Prandtl, and the refinements by Horten, Jones, Kline, Viswanathan, and Whitcomb.

Bowers, Albion H.

2011-01-01

428

Response Selectivity Is Correlated to Dendritic Structure in Parvalbumin-Expressing Inhibitory Neurons in Visual Cortex  

E-print Network

Inhibitory neurons have been shown to perform a variety of functions within brain circuits, including shaping response functions in target cells. Still, how the properties of specific inhibitory neuron classes relate to ...

Runyan, Caroline A.

429

Changes of proteolysis and angiotensin-I converting enzyme-inhibitory activity in white-brined cheese as affected by adjunct culture and ripening temperature.  

PubMed

The effects of use of adjunct cultures (Lactobacillus helveticus and Lb. casei) and ripening temperatures (6 or 12 °C) on proteolysis and angiotensin-I converting enzyme (ACE)-inhibitory activity in white-brined cheeses were investigated during 120 d ripening. Proteolysis was monitored by urea-polyacrylamide gel electrophoresis (urea-PAGE) and reversed phase-HPLC (RP-HPLC) of water-insoluble and -soluble fractions of the cheeses, respectively. Urea-PAGE patterns of the samples revealed that the intensities of the bands representing casein fractions decreased in the experimental cheeses, being more pronounced in the cheeses made with adjunct cultures. Similarly, peptide profiles and the concentrations of individual and total free amino acids were influenced by both the adjunct cultures and ripening temperatures. The ACE-inhibitory activity of the water-soluble extracts of the cheeses were higher in the cheeses made using adjunct cultures (especially Lb. helveticus) and ripened at 12 °C. The ACE-inhibitory activity did not decrease during ripening. The contribution of Lb. helveticus to the development of proteolysis and ACE-inhibitory peptide activities were higher than that of Lb. casei. To conclude, the use of Lb. helveticus as adjunct culture in white-brined cheese and ripening at 12 °C would be recommended to obtain white-brined cheese with high ACE-I-inhibitory peptides activity and higher levels of preoteolysis. PMID:25017295

Sahingil, Didem; Hayaloglu, Ali A; Kirmaci, Huseyin A; Ozer, Barbaros; Simsek, Osman

2014-11-01

430

A Universal Model for Halo Concentrations  

NASA Astrophysics Data System (ADS)

We present a numerical study of dark matter halo concentrations in ?CDM and self-similar cosmologies. We show that the relation between concentration, c, and peak height, ?, exhibits the smallest deviations from universality if halo masses are defined with respect to the critical density of the universe. These deviations can be explained by the residual dependence of concentration on the local slope of the matter power spectrum, n, which affects both the normalization and shape of the c-? relation. In particular, there is no well-defined floor in the concentration values. Instead, the minimum concentration depends on redshift: at fixed ?, halos at higher z experience steeper slopes n, and thus have lower minimum concentrations. We show that the concentrations in our simulations can be accurately described by a universal seven-parameter function of only ? and n. This model matches our ?CDM results to <~ 5% accuracy up to z = 6, and matches scale-free ?m = 1 models to <~ 15%. The model also reproduces the low concentration values of Earth-mass halos at z ? 30, and thus correctly extrapolates over 16 orders of magnitude in halo mass. The predictions of our model differ significantly from all models previously proposed in the literature at high masses and redshifts. Our model is in excellent agreement with recent lensing measurements of cluster concentrations.

Diemer, Benedikt; Kravtsov, Andrey V.

2015-01-01

431

Meteoritic evidence for the Maunder minimum in solar activity  

NASA Technical Reports Server (NTRS)

Concentrations of argon-39 produced by cosmic rays in the metal in 30 meteorites are remarkably similar, but they are slightly higher than expected for the present solar-cycle-averaged flux of cosmic rays. This supports the idea suggested by Eddy (1976) that there were prolonged minima in solar activity before 1715 which caused the deVries maximum in carbon-14 in earth's atmosphere by reducing the amount of cosmic-ray modulation in interplanetary space. The observations are easily consistent with 180 years of 'sunspot minimum' modulation during the Maunder and Spoerer minima, and possibly with virtually no solar modulation at all during that time. This would indicate that the solar wind then contained very little magnetic turbulence or whatever it is in the solar wind that causes the modulation of galactic cosmic rays.

Forman, M. A.; Schaeffer, O. A.; Schaeffer, G. A.

1978-01-01

432

Mungbean Protein Hydrolysates Obtained with Alcalase Exhibit Angiotensin I-converting Enzyme Inhibitory Activity  

Microsoft Academic Search

Mung-bean protein isolates were hydrolysed by two proteases alcalase and neutrase commercially available for food industry use, and the angiotensin I-converting enzyme (ACE) inhibitory activities of the enzymatic hydrolysates were measured at different hydrolysis times. The non-hydrolysed protein showed no inhibitory activity. Hydrolysates generated with neutrase displayed very low ACE inhibitory activity, while those obtained with alcalase exhibited high inhibitory

Guan Hong Li; Guo Wei Le; Huan Liu; Yong Hui Shi

2005-01-01

433

The Role of Inhibitory Control in Behavioral and Physiological Expressions of Toddler Executive Function  

ERIC Educational Resources Information Center

A total of 81 toddlers (24-27 months of age) participated in a biobehavioral investigation of inhibitory control. Maternal report measures of inhibitory control were related to laboratory tasks assessing inhibitory abilities under conditions of conflict, delay, and compliance challenge as well as toddler verbal ability. In addition, unique…

Morasch, Katherine C.; Bell, Martha Ann

2011-01-01

434

Tyrosinase Inhibitory and Antioxidant Activities of Essential Oil from Thai Spices  

Microsoft Academic Search

The aim of this work was to evaluate the tyrosinase inhibitory activity and the antioxidant power of the essential oils from spice plants commonly used in Thai food. Fresh samples of eleven different plant species were extracted and the essential oil of each was obtained by hydrodistillation. The tyrosinase inhibitory test was performed by using mushroom tyrosinase. The inhibitory power

Kiattisak Saeio; Songwut Yotsawimonwat; Siriporn Okonogi

435

2005 Nature Publishing Group GABA (-aminobutyric acid) is the main inhibitory  

E-print Network

© 2005 Nature Publishing Group GABA (-aminobutyric acid) is the main inhibitory neurotransmitter,this leads to a net inward flow of anions and a hyperpolarizing post- synaptic response -- the inhibitory ON AN INHIBITORY THEME: PHASIC AND TONIC ACTIVATION OF GABAA RECEPTORS Mark Farrant* and Zoltan Nusser Abstract

Sandini, Giulio

436

Prediction of PKC? Inhibitory Activity Using the Random Forest Algorithm  

PubMed Central

This work is devoted to the prediction of a series of 208 structurally diverse PKC? inhibitors using the Random Forest (RF) based on the Mold2 molecular descriptors. The RF model was established and identified as a robust predictor of the experimental pIC50 values, producing good external R2pred of 0.72, a standard error of prediction (SEP) of 0.45, for an external prediction set of 51 inhibitors which were not used in the development of QSAR models. By using the RF built-in measure of the relative importance of the descriptors, an important predictor—the number of group donor atoms for H-bonds (with N and O)—has been identified to play a crucial role in PKC? inhibitory activity. We hope that the developed RF model will be helpful in the screening and prediction of novel unknown PKC? inhibitory activity. PMID:20957104

Hao, Ming; Li, Yan; Wang, Yonghua; Zhang, Shuwei

2010-01-01

437

Acetylcholinesterase and Butyrylcholinesterase inhibitory activities of Berberis vulgaris  

E-print Network

Berberis vulgaris is a famous medicinal plant used in folk medicine for a variety of pathological condition. Aim of the study was to determine cholinesterase inhibitory effects of crude extracts and fractions of Berberis vulgaris. Considerable inhibition of acetylcholinesterase was observed in majority cases. The hexane fraction was the most active fraction with the IC50 being 68±0.028 µg/ml. In case of butyrylcholinesterase, crude extract of the leaves found to be the most active sample with (64%) inhibition and its IC50 value was 59±0.058 µg/ml. In case of fractions, aqueous fraction of crude bark extract showed most potent inhibitory profile (IC50: 59±0.058 µg/ml). Results indicated promising potential of B. vulgaris as source of new compounds for management of Alzheimer’s Disease.

D. Kolá?; L. Wimmerová; R. Kádek

438

In vitro survey of alpha-glucosidase inhibitory food components.  

PubMed

A survey of food components with alpha-glucosidase (AGH) inhibitory activity was conducted to identify a prophylactic effect for diabetes in food. Sardine muscle hydrolyzed by alkaline protease showed potent activity (IC50 = 48.7 mg/ml) as well as green and oolong teas (IC50 = 11.1 and 11.3 mg/ml, respectively). Furthermore, hydrolyzates prepared by various proteases gave differing AGH inhibitory activity. DEAE-Sephadex chromatography of the alkaline protease hydrolyzate eluted potent AGH inhibitors (IC50 = 15.6 mg/ml) with a 50 mM phosphate buffer (pH 7.0) containing 0.3 M NaCl, and their subsequent separation by HPLC in an ODS column showed that there were some inhibitors possessing primary amino groups. This indicates that they would have been high anionic and peptidic compounds. PMID:8988634

Matsui, T; Yoshimoto, C; Osajima, K; Oki, T; Osajima, Y

1996-12-01

439

Dihydroasparagusic acid: antioxidant and tyrosinase inhibitory activities and improved synthesis.  

PubMed

Dihydroasparagusic acid (DHAA) is the reduced form of asparagusic acid, a sulfur-containing flavor component produced by Asparagus plants. In this work, DHAA was synthetically produced by modifying some published protocols, and the synthesized molecule was tested in several in vitro assays (DPPH, ABTS, FRAP-ferrozine, BCB, deoxyribose assays) to evaluate its radical scavenging activity. Results show that DHAA is endowed with a significant in vitro antioxidant activity, comparable to that of Trolox. DHAA was also evaluated for its inhibitory activity toward tyrosinase, an enzyme involved, among others, in melanogenesis and in browning processes of plant-derived foods. DHAA was shown to exert an inhibitory effect on tyrosinase activity, and the inhibitor kinetics, analyzed by a Lineweaver-Burk plot, exhibited a competitive mechanism. Taken together, these results suggest that DHAA may be considered as a potentially active molecule for use in various fields of application, such as pharmaceutical, cosmetics, agronomic and food. PMID:23790134

Venditti, Alessandro; Mandrone, Manuela; Serrilli, Anna Maria; Bianco, Armandodoriano; Iannello, Carmelina; Poli, Ferruccio; Antognoni, Fabiana

2013-07-17

440

Synthesis, topoisomerase I inhibitory and cytotoxic activities of chromone derivatives.  

PubMed

A series of chromone derivatives were designed as potential topoisomerase I (Top I) inhibitors based on the docking simulation study. Sixteen synthesized compounds were evaluated for Top I inhibitory activity and some compounds were further tested for in vitro cytotoxic activity. The most potent inhibitor, chromone 11b showed greater inhibitory activity (IC50 = 1.46 ?M) than the known Top I inhibitors, i.e., camptothecin, fisetin and morin, but inactive against breast cancer cell (MCF-7), oral cavity cancer cell (KB) and small cell lung cancer (NCI-H187). Chromone 11c, another potent inhibitor (IC50 = 6.16 ?M), exhibited cytotoxic activity against KB (IC50 = 73.32 ?M) and NCI-H187 (IC50 = 36.79 ?M). PMID:23030699

Maicheen, Chirattikan; Jittikoon, Jiraphun; Vajragupta, Opa; Ungwitayatorn, Jiraporn

2013-05-01