WorldWideScience

Sample records for blood bactericidal activity

  1. Phagocytic and bactericidal activities of leukocytes in whole blood from atomic bomb survivors

    International Nuclear Information System (INIS)

    Sasagawa, S.; Yoshimoto, Y.; Toyota, E.; Neriishi, S.; Yamakido, M.; Matsuo, M.; Hosoda, Y.; Finch, S.C.

    1990-01-01

    This study evaluated the phagocytic and bactericidal activities of peripheral blood leukocytes from Hiroshima and Nagasaki atomic bomb survivors for Staphylococcus aureus. The data were analyzed by multiple linear regression for age, sex, radiation exposure, city of exposure, and neutrophil counts. No significant radiation effect was observed for either blood phagocytic or bactericidal activities. The only significant variable for these functions was the neutrophil count

  2. Whole-blood phagocytic and bactericidal activities of atomic bomb survivors, Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    Sasagawa, Sumiko; Yoshimoto, Yasuhiko; Toyota, Emiko; Neriishi, Shotaro; Yamakido, Michio; Matsuo, Miyo; Hosoda, Yutaka; Finch, S.C.

    1989-04-01

    This in vitro study evaluated the phagocytic and bactericidal activities of leukocytes in aliquots of whole blood from Hiroshima and Nagasaki atomic bomb survivors for Staphylococcus aureus. The data were analyzed by multiple linear regression. Any significant effects of exposure to A-bomb radiation could not be detected for both phagocytic and bactericidal activities of whole blood from A-bomb survivors. In addition, there were no significant effects of age categories, sex or city, except in neutrophil counts. (J.P.N.)

  3. BACTERICIDAL ACTIVITY OF HUMAN SERA AGAINST ...

    African Journals Online (AJOL)

    hi-tech

    2000-12-12

    Dec 12, 2000 ... and Salmonella paratyphi A,B,C. There was no difference in resistance pattern when blood was pooled in respect to their group types. Age or sex of the blood donors had no effect on the bactericidal activity of the sera. Conclusion: Blood group is an important factor in the susceptibility or resistance of an.

  4. Phagocytic activity of granulocytes and bactericidal properties of the blood plasma in the course of radiotherapy of cancer of the lung

    International Nuclear Information System (INIS)

    Wysocka, J.; Kemona, H.; Kiluk, S.; Prokopowicz, J.

    1986-01-01

    Functional condition of granulocytes and bactericidal properties of blood plasma in patients with lung cancer, as well as the effect of radiotherapy on these parameters has been evaluated. Prior to the treatment decrease of the phagocytic activity and bactericidal properties of the blood plasma have been noticed. Application of radiotherapy is not resulting in total restitution of normal functional condition of granulocytes and even deteriorates temporarily the condition of the humoral resistance. Definition of the condition of non specific resistance is important for evaluation of the degree of exposure of patients with bacterial infections. 30 refs. (author)

  5. Bactericidal activity of biomimetic diamond nanocone surfaces.

    Science.gov (United States)

    Fisher, Leanne E; Yang, Yang; Yuen, Muk-Fung; Zhang, Wenjun; Nobbs, Angela H; Su, Bo

    2016-03-17

    The formation of biofilms on implant surfaces and the subsequent development of medical device-associated infections are difficult to resolve and can cause considerable morbidity to the patient. Over the past decade, there has been growing recognition that physical cues, such as surface topography, can regulate biological responses and possess bactericidal activity. In this study, diamond nanocone-patterned surfaces, representing biomimetic analogs of the naturally bactericidal cicada fly wing, were fabricated using microwave plasma chemical vapor deposition, followed by bias-assisted reactive ion etching. Two structurally distinct nanocone surfaces were produced, characterized, and the bactericidal ability examined. The sharp diamond nanocone features were found to have bactericidal capabilities with the surface possessing the more varying cone dimension, nonuniform array, and decreased density, showing enhanced bactericidal ability over the more uniform, highly dense nanocone surface. Future research will focus on using the fabrication process to tailor surface nanotopographies on clinically relevant materials that promote both effective killing of a broader range of microorganisms and the desired mammalian cell response. This study serves to introduce a technology that may launch a new and innovative direction in the design of biomaterials with capacity to reduce the risk of medical device-associated infections.

  6. Bactericidal activity of ACH-702 against nondividing and biofilm Staphylococci.

    Science.gov (United States)

    Podos, Steven D; Thanassi, Jane A; Leggio, Melissa; Pucci, Michael J

    2012-07-01

    Many bacterial infections involve slow or nondividing bacterial growth states and localized high cell densities. Antibiotics with demonstrated bactericidal activity rarely remain bactericidal at therapeutic concentrations under these conditions. The isothiazoloquinolone (ITQ) ACH-702 is a potent, bactericidal compound with activity against many antibiotic-resistant pathogens, including methicillin-resistant Staphylococcus aureus (MRSA). We evaluated its bactericidal activity under conditions where bacterial cells were not dividing and/or had slowed their growth. Against S. aureus cultures in stationary phase, ACH-702 showed concentration-dependent bactericidal activity and achieved a 3-log-unit reduction in viable cell counts within 6 h of treatment at ≥ 16× MIC values; in comparison, the bactericidal quinolone moxifloxacin and the additional comparator compounds vancomycin, linezolid, and rifampin at 16× to 32× MICs showed little or no bactericidal activity against stationary-phase cells. ACH-702 at 32× MIC retained bactericidal activity against stationary-phase S. aureus across a range of inoculum densities. ACH-702 did not kill cold-arrested cells yet remained bactericidal against cells arrested by protein synthesis inhibitors, suggesting that its bactericidal activity against nondividing cells requires active metabolism but not de novo protein synthesis. ACH-702 also showed a degree of bactericidal activity at 16× MIC against S. epidermidis biofilm cells that was superior to that of moxifloxacin, rifampin, and vancomycin. The bactericidal activity of ACH-702 against stationary-phase staphylococci and biofilms suggests potential clinical utility in infections containing cells in these physiological states.

  7. [Bactericidal activity of sitafloxacin and other new quinolones against antimicrobial resistant Streptococcus pneumoniae].

    Science.gov (United States)

    Kobayashi, Intetsu; Kanayama, Akiko; Hasegawa, Miyuki; Kaneko, Akihiro

    2013-02-01

    We conducted a study assess the bactericidal activity of sitafloxacin (STFX) against Streptococcus pneumoniae isolates recovered from respiratory infections including penicillin-resistant (PRSP) isolates, macrolide resistant isolates possessing mefA and ermB resistance genes and quinolone resistance isolates with mutations in gyrA or gyrA and parC. Each isolate tested was grown in hemosupplemented Mueller-Hinton broth and adjusted to approximately 10(5) CFU/ mL. Isolates were than exposed to a Cmax antimicrobial blood level that would be attained with routine antimicrobial administration and an antimicrobial level that would be expected 4 hours post-Cmax (Cmax 4hr). Bactericidal activity was measured for up to 8 hours. Excluding a subset of S. pneumoniae isolates with mutations in the quinolone resistance determining region (QRDR), all quinolones showed bactericidal activity at Cmax and Cmax 4 hr antimicrobial concentrations for up to 8 hours. Against S. pneumoniae isolates with either gyrA or gyrA and parC mutations, bactericidal activity of STFX was shown for up to 4 to 8 hours following Cmax based on a limit of detection of bactericidal activity below the limit of detection for up to 8 hours with exposure to Cmax and no bactericidal activity was seen with levofloxacin. When all quinolones tested where adjusted to concentrations corresponding to their MICs, STFX showed the most rapid bactericidal activity against PRSP. This rapid bactericidal activity in PRSP is a key to the effectiveness of STFX. Our findings show that beyond inhibition of bacterial replication by blocking their DNA replication pathway and synthesis of proteins, STFX demonstrated characteristics contributing to greater bactericidal activity compared to GRNX. In conclusion, of the newer quinolones, STFX showed the strongest bactericidal activity against S. pneumoniae isolates with mutations in the QRDR which indicates that it may show the most effective clinical utility among the quinolones in

  8. Bactericidal activity of partially oxidized nanodiamonds.

    Science.gov (United States)

    Wehling, Julia; Dringen, Ralf; Zare, Richard N; Maas, Michael; Rezwan, Kurosch

    2014-06-24

    Nanodiamonds are a class of carbon-based nanoparticles that are rapidly gaining attention, particularly for biomedical applications, i.e., as drug carriers, for bioimaging, or as implant coatings. Nanodiamonds have generally been considered biocompatible with a broad variety of eukaryotic cells. We show that, depending on their surface composition, nanodiamonds kill Gram-positive and -negative bacteria rapidly and efficiently. We investigated six different types of nanodiamonds exhibiting diverse oxygen-containing surface groups that were created using standard pretreatment methods for forming nanodiamond dispersions. Our experiments suggest that the antibacterial activity of nanodiamond is linked to the presence of partially oxidized and negatively charged surfaces, specifically those containing acid anhydride groups. Furthermore, proteins were found to control the bactericidal properties of nanodiamonds by covering these surface groups, which explains the previously reported biocompatibility of nanodiamonds. Our findings describe the discovery of an exciting property of partially oxidized nanodiamonds as a potent antibacterial agent.

  9. Investigation of tigecycline bactericidal activity: Optimisation of laboratory testing.

    Science.gov (United States)

    Usacheva, Elena A; Grayes, Althea; Schora, Donna; Peterson, Lance R

    2014-12-01

    The objectives of this study were to optimise the conditions for bactericidal testing of tigecycline and to investigate its bactericidal activity against clinical isolates of Gram-positive and Gram-negative bacteria. Tigecycline is the first in a new class of glycylcycline antibiotics exhibiting in vitro activity against a broad range of bacteria, including multidrug-resistant organisms. Its bactericidal activity in vitro has not been extensively investigated using multiple test conditions. Five growth media comprising Mueller Hinton broth, Minimum Essential Medium of Eagle, Ham F-12, RPMI 1640 and Iso-Sensitest broth (ISB) with and without surfactant (Tween 80) were investigated in vitro to assess tigecycline bactericidal activity. Clinical isolates of meticillin-resistant Staphylococcus aureus, meticillin-susceptible S. aureus, Escherichia coli, Klebsiella pneumoniae and Enterococcus spp., representing the majority of clinically relevant bacteria, were evaluated for the impact of test conditions on the tigecycline minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), ISB with 0.02% Tween 80 most efficiently demonstrated the bactericidal action of tigecycline when evaluated in 64 well-characterised clinical isolates and was considered as the optimal bactericidal test medium. Using this condition, tigecycline approached 56% bactericidal activity with 3log 10 reduction in CFUs at 72h incubation. Bactericidal action increased to 80% of strains when 2log 10 reduction was used as the endpoint. Only Enterococcus spp. showed no bactericidal response in this analysis. Tigecycline exhibited a bactericidal effect in vitro against Gram-positive and Gram-negative bacteria. At the tested in vitro conditions, tigecycline MICs were unchanged regardless of the different test media used. Copyright © 2014 International Society for Chemotherapy of Infection and Cancer. Published by Elsevier Ltd. All rights reserved.

  10. Rapid bactericidal activity of sitafloxacin against Streptococcus pneumoniae.

    Science.gov (United States)

    Kanda, Hiroko; Inoue, Kazue; Okumura, Ryo; Hoshino, Kazuki

    2013-02-01

    The initial bactericidal activity of quinolones against Streptococcus pneumoniae at the concentration equivalent to their respective peak serum concentration (C(max)) and free drug fraction of C(max) (fC(max)) were investigated. The bactericidal activity of sitafloxacin (STFX), levofloxacin (LVFX), moxifloxacin (MFLX), and garenoxacin (GRNX) were compared by determining the actual killing of bacteria at C(max) and fC(max) for 1 and 2 hours based on the Japanese maximum dose per administration (100, 500, 400, and 400 mg, respectively). Against 4 quinolone-susceptible clinical isolates (wild-type), STFX with C(max) and fC(max) exhibited the most rapid bactericidal activity resulting in an average reduction of > or = 3.0 log10 colony forming units (CFU)/ mL in 1 hour. STFX with C(max) and fC(max) also showed the most rapid and potent bactericidal activity against 9 clinical isolates with single par (C/E) mutation, resulting in > or = 3.0 log10 CFU/mL average reduction in viable cells in 1 hour. STFX showed a statistically significant advantage in initial bactericidal activity over other quinolones for single mutants (P bactericidal activity between STFX and other quinolones was higher in single mutants than wild-type strains, was confirmed using S. pneumoniae ATCC49619 (wild-type) and its laboratory single parC mutant. As a result, STFX showed a similar rapid and potent initial bactericidal activity against both strains, while initial bactericidal activity for other quinolones was significantly reduced in the single mutant (P bactericidal activity against wild-type and single mutants of S. pneumoniae and its bactericidal activity is not affected by the presence of a single par mutation compared to LVFX, MFLX, and GRNX.

  11. The Stability of Complement-Mediated Bactericidal Activity in Human Serum against Salmonella

    Science.gov (United States)

    O’Shaughnessy, Colette M.; Cunningham, Adam F.; MacLennan, Calman A.

    2012-01-01

    The complement cascade includes heat-labile proteins and care is required when handling serum in order to preserve its functional integrity. We have previously used a whole human serum bactericidal assay to show that antibody and an intact complement system are required in blood for killing of invasive isolates of Salmonella. The aim of the present study was to evaluate the conditions under which human serum can be stored and manipulated while maintaining complement integrity. Serum bactericidal activity against Salmonella was maintained for a minimum of 35 days when stored at 4°C, eight days at 22°C and 54 hours at 37°C. Up to three freeze-thaw cycles had no effect on the persistence of bactericidal activity and hemolytic complement assays confirmed no effect on complement function. Delay in the separation of serum for up to four days from clotted blood stored at 22°C did not affect bactericidal activity. Dilution of serum resulted in an increased rate of loss of bactericidal activity and so serum should be stored undiluted. These findings indicate that the current guidelines concerning manipulation and storage of human serum to preserve complement integrity and function leave a large margin for safety with regards to bactericidal activity against Salmonella. The study provides a scheme for determining the requirements for serum handling in relation to functional activity of complement in other systems. PMID:23145102

  12. Effects of freezing on the bactericidal activity of human milk.

    Science.gov (United States)

    Takci, Sahin; Gulmez, Dolunay; Yigit, Sule; Dogan, Ozlem; Dik, Kezban; Hascelik, Gulsen

    2012-08-01

    Storage of human milk by freezing has been recommended for long-term storage. The present study analyzed the bactericidal activity of human milk on Escherichia coli and Pseudomonas aeruginosa and determined the changes in bactericidal activity following freezing at -20°C and -80°C for 1 month and 3 months. Forty-eight milk samples were collected from 48 lactating mothers. Each sample was divided into 10 aliquots. Two of the samples were processed immediately and the others were stored at both -20°C and -80°C until analysis after 1 month and 3 months of freezing. All of the fresh milk samples showed bactericidal activity against E coli and P aeruginosa. Freezing at -20°C for 1 month did not cause statistically significant alteration in bactericidal activity (P > 0.017), whereas storage for 3 months lowered the degree of bactericidal activity significantly (P Bactericidal activity was protected when the samples were stored at -80°C. There was no statistically significant difference in the bactericidal activity of human milk against E coli between freezing at -20°C and -80°C for 1 month (P > 0.017); however, when milk was stored for 3 months, -80°C was significantly more protective (P bactericidal activity against P aeruginosa (P > 0.05). Storage by freezing at -80°C is more appropriate to keep bactericidal capacity of stored human milk >1 month if affordable and available, especially in intensive care settings.

  13. Lack of antimicrobial bactericidal activity in Mycobacterium abscessus.

    Science.gov (United States)

    Maurer, Florian P; Bruderer, Vera L; Ritter, Claudia; Castelberg, Claudio; Bloemberg, Guido V; Böttger, Erik C

    2014-07-01

    Antibiotic therapy of infections caused by the emerging pathogen Mycobacterium abscessus is challenging due to the organism's natural resistance toward most clinically available antimicrobials. We investigated the bactericidal activity of antibiotics commonly administered in M. abscessus infections in order to better understand the poor therapeutic outcome. Time-kill curves were generated for clinical M. abscessus isolates, Mycobacterium smegmatis, and Escherichia coli by using antibiotics commonly categorized as bactericidal (amikacin and moxifloxacin) or bacteriostatic (tigecycline and linezolid). In addition, the impact of aminoglycoside-modifying enzymes on the mode of action of substrate and nonsubstrate aminoglycosides was studied by using M. smegmatis as a model organism. While amikacin and moxifloxacin were bactericidal against E. coli, none of the tested compounds showed bactericidal activity against M. abscessus. Further mechanistic investigations of the mode of action of aminoglycosides in M. smegmatis revealed that the bactericidal activity of tobramycin and gentamicin was restored by disruption of the chromosomal aac(2') gene in the mycobacterial genome. The lack of bactericidal antibiotics in currently recommended treatment regimens provides a reasonable explanation for the poor therapeutic outcome in M. abscessus infection. Our findings suggest that chromosomally encoded drug-modifying enzymes play an important role in the lack of aminoglycoside bactericidal activity against rapidly growing mycobacteria. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  14. Two Major Medicinal Honeys Have Different Mechanisms of Bactericidal Activity

    Science.gov (United States)

    Kwakman, Paulus H. S.; te Velde, Anje A.; de Boer, Leonie; Vandenbroucke-Grauls, Christina M. J. E.; Zaat, Sebastian A. J.

    2011-01-01

    Honey is increasingly valued for its antibacterial activity, but knowledge regarding the mechanism of action is still incomplete. We assessed the bactericidal activity and mechanism of action of Revamil® source (RS) honey and manuka honey, the sources of two major medical-grade honeys. RS honey killed Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa within 2 hours, whereas manuka honey had such rapid activity only against B. subtilis. After 24 hours of incubation, both honeys killed all tested bacteria, including methicillin-resistant Staphylococcus aureus, but manuka honey retained activity up to higher dilutions than RS honey. Bee defensin-1 and H2O2 were the major factors involved in rapid bactericidal activity of RS honey. These factors were absent in manuka honey, but this honey contained 44-fold higher concentrations of methylglyoxal than RS honey. Methylglyoxal was a major bactericidal factor in manuka honey, but after neutralization of this compound manuka honey retained bactericidal activity due to several unknown factors. RS and manuka honey have highly distinct compositions of bactericidal factors, resulting in large differences in bactericidal activity. PMID:21394213

  15. Hydrophobic determinants of α-defensin bactericidal activity.

    Science.gov (United States)

    Tai, Kenneth P; Le, Valerie V; Selsted, Michael E; Ouellette, André J

    2014-06-01

    Mammalian α-defensins are approximately 4- to 5-kDa broad-spectrum antimicrobial peptides and abundant granule constituents of neutrophils and small intestinal Paneth cells. The bactericidal activities of amphipathic α-defensins depend in part on electropositive charge and on hydrophobic amino acids that enable membrane disruption by interactions with phospholipid acyl chains. Alignment of α-defensin primary structures identified conserved hydrophobic residues in the loop formed by the Cys(III)-Cys(V) disulfide bond, and we have studied their role by testing the effects of mutagenesis on bactericidal activities. Mouse α-defensin 4 (Crp-4) and rhesus myeloid α-defensin 4 (RMAD-4) were selected for these studies, because they are highly bactericidal in vitro and have the same overall electropositive charge. Elimination of hydrophobicity by site-directed mutagenesis at those positions in Crp-4 attenuated bactericidal activity markedly. In contrast to native Crp-4, the (I23/F25/L26/G)-Crp-4 variant lacked bactericidal activity against Salmonella enterica serovar Typhimurium and did not permeabilize Escherichia coli ML35 cells as a result of removing aliphatic side chains by Gly substitutions. Ala replacements in (I23/F25/L26/A)-Crp-4 restored activity, evidence that hydrophobicity contributed by Ala methyl R-groups was sufficient for activity. In macaques, neutrophil α-defensin RMAD-6 is identical to RMAD-4, except for a F28S difference, and (F28S)-RMAD-4 mutagenesis attenuated RMAD-4 bactericidal activity and E. coli permeabilization. Interestingly, (R31/32D)-Crp-4 lacks activity in these assays despite the presence of the Ile23, Phe25, and Leu26 hydrophobic patch. We infer that electrostatic interactions between cationic α-defensin residues and negative charge on bacteria precede interactions between critical hydrophobic residue positions that mediate membrane disruption and bacterial cell killing.

  16. Two Major Medicinal Honeys Have Different Mechanisms of Bactericidal Activity

    NARCIS (Netherlands)

    Kwakman, P.H.S.; te Velde, A.A.; de Boer, L.; Vandenbroucke-Grauls, C.M.J.E.; Zaat, S.A.J.

    2011-01-01

    Honey is increasingly valued for its antibacterial activity, but knowledge regarding the mechanism of action is still incomplete. We assessed the bactericidal activity and mechanism of action of Revamil (R) source (RS) honey and manuka honey, the sources of two major medical-grade honeys. RS honey

  17. Involvement of p38MAPK in Impaired Neutrophil Bactericidal Activity of Hemodialysis Patients.

    Science.gov (United States)

    Kamikawa, Yasutaka; Sakai, Norihiko; Miyake, Taito; Sagara, Akihiro; Shinozaki, Yasuyuki; Kitajima, Shinji; Toyama, Tadashi; Hara, Akinori; Iwata, Yasunori; Shimizu, Miho; Furuichi, Kengo; Imamura, Ryu; Suda, Takashi; Kaneko, Shuichi; Wada, Takashi

    2018-01-10

    Mortality from infections has been reported to be higher in hemodialysis (HD) patients. Although dysfunction of neutrophils against bacterial infection was reported in HD patients, the precise mechanism remains to be clarified. We therefore examined the impacts of neutrophil inflammatory signaling on bactericidal activity in HD patients. Comprehensive analyses of intracellular signalings were performed in whole blood of HD patients and control using a microarray system. To confirm the contribution of the signaling to bactericidal activity in neutrophils, we examined the phosphorylation, bacterial killing function, reactive oxygen species (ROS) production, and myeloperoxidase (MPO) release in neutrophils against Staphylococcus aureus. RNA microarray analysis showed the suppression of p38 mitogen activated protein kinase (MAPK) signaling in HD patients. Neutrophils in HD patients showed the impairment of bactericidal activity against S. aureus compared to healthy subjects. Phosphorylation rate of p38MAPK of neutrophils in response to S. aureus was lower in HD patients than healthy subjects. The levels of ROS produced by neutrophils after co-culture with S. aureus were lower in HD patients, on the other hand, there was no difference of MPO release between HD patients and healthy subjects. A selective pharmacological inhibitor of p38MAPK suppressed bacterial killing function as well as ROS production in neutrophils of healthy subjects. Impairment of p38MAPK signaling pathway might contribute to the suppression of neutrophil bactericidal activity in HD patients through less production of ROS. © 2018 International Society for Apheresis, Japanese Society for Apheresis, and Japanese Society for Dialysis Therapy.

  18. Bactericidal activity of titanium dioxide ultraviolet-induced films

    Energy Technology Data Exchange (ETDEWEB)

    Pleskova, S.N., E-mail: pleskova@mail.ru [Laboratory of Biochemistry and Molecular Biology, Tomsk State University, ave. Lenina 36, Tomsk 634050 (Russian Federation); Golubeva, I.S., E-mail: golubmay@mail.ru [Institute of applied biotechnology of Nizhny Novgorod, Yablonevaya Street 22, Nizhny Novgorod 603093 (Russian Federation); Verevkin, Y.K., E-mail: verevkin@appl.sci-nnov.ru [Institute of applied physics of the Russian Academy of Science, Ul' yanov Street, 46, Nizhny Novgorod 603950 (Russian Federation)

    2016-02-01

    TiO{sub 2} films are used as a self-sterilization surface due to their property to form reactive oxygen species (ROS) when irradiated with ultraviolet light. These ROS attack bacteria and kill them. We present a new way to enhance the bactericidal activity of TiO{sub 2}-films: formation of nanopores on the surface by four-beam high-power laser irradiation. Such surfaces have significantly higher antibacterial activity as compared to conventional TiO{sub 2} surfaces after 15 and 60 min of UV irradiation. Study of the bacterial cell morphology by atomic force microscopy after 60 min irradiation showed that Staphylococcus aureus 956 and Escherichia coli 321–5 undergo significant morphological changes. S. aureus assume atypical elongated shapes after UV treatment alone and swollen forms with protrusions after UV treatment on TiO{sub 2} surface. E. coli exhibit oval or round forms after UV treatment alone, and round forms with small protrusions, and destroyed cells after incubation under UV on the TiO{sub 2} film. - Highlights: • Nanopores on the TiO{sub 2} surface enhance the bactericidal activity of films. • The bactericidal effect of TiO{sub 2} is strain-specific. • The bacterial morphology significantly changes after UV/TiO{sub 2} treatment.

  19. Nanostructured surface topographies have an effect on bactericidal activity.

    Science.gov (United States)

    Wu, Songmei; Zuber, Flavia; Maniura-Weber, Katharina; Brugger, Juergen; Ren, Qun

    2018-02-28

    Due to the increased emergence of antimicrobial resistance, alternatives to minimize the usage of antibiotics become attractive solutions. Biophysical manipulation of material surface topography to prevent bacterial adhesion is one promising approach. To this end, it is essential to understand the relationship between surface topographical features and bactericidal properties in order to develop antibacterial surfaces. In this work a systematic study of topographical effects on bactericidal activity of nanostructured surfaces is presented. Nanostructured Ormostamp polymer surfaces are fabricated by nano-replication technology using nanoporous templates resulting in 80-nm diameter nanopillars. Six Ormostamp surfaces with nanopillar arrays of various nanopillar densities and heights are obtained by modifying the nanoporous template. The surface roughness ranges from 3.1 to 39.1 nm for the different pillar area parameters. A Gram-positive bacterium, Staphylococcus aureus, is used as the model bacterial strain. An average pillar density at ~ 40 pillars μm -2 with surface roughness of 39.1 nm possesses the highest bactericidal efficiency being close to 100% compared with 20% of the flat control samples. High density structures at ~ 70 pillars μm -2 and low density structures at bactericidal efficiency to almost the level of the control samples. The results obtained here suggests that the topographical effects including pillar density and pillar height inhomogeneity may have significant impacts on adhering pattern and stretching degree of bacterial cell membrane. A biophysical model is prepared to interpret the morphological changes of bacteria on these nanostructures.

  20. Bactericidal activities of parenteral antibiotics and genotype of penicillin-binding protein in Streptococcus pneumoniae and Haemophilus influenzae isolated from children's blood.

    Science.gov (United States)

    Sakata, Hiroshi

    2006-10-01

    A total of 16 isolates of Streptococcus pneumoniae and 18 isolates of Haemophilus influenzae were obtained from the blood of children admitted to the pediatric wards of hospitals in Hokkaido Kamikawa subprefecture between January 2003 and December 2005. The ages of the patients with S. pneumoniae or H. influenzae infection ranged from 2 months to 9 years and from 1 month to 4 years, respectively. The diagnoses of S. pneumoniae infection were as follows: pneumonia in 8 patients, occult bacteremia in 5 patients, and meningitis in 3 patients. The diagnoses of H. influenzae were: meningitis in 6 patients, pneumonia in 4 patients, occult bacteremia in 4 patients, epiglotitis in 2 patients, and facial cellulitis in 2 patients. Out of 16 S. pneumoniae isolates, penicillin-resistant strains with a mutation of 3 genes were observed in 7 children, and penicillin intermediate-resistant strains with a mutation of 1 or 2 genes were observed in 8 children. Out of 18 H. influenzae isolates, the beta-lactamase-negative ampicillin-resistant strain with a substitution of 2 points in the ftsI gene was revealed in 2 children, the beta-lactamase-negative ampicillin-resistant strain with a substitution of 1 point in the ftsI gene was observed in 4 children, the beta-lactamase-positive amoxicillin/clavulanic acid-resistant strain with blaTEM-1 and ftsI with 2 substitutions in the ftsI gene was observed in 3 children, and the beta-lactamase-positive ampicillin-resistant strain with blaTEM-1was not observed. The MBC90s of ampicillin, ceftriaxone, cefotaxime, meropenem, panipenem, and vancomycin against S. pneumoniae were 8 microg/ml, 1 microg/ml, 1 microg/ml 1 microg/ml, 0.25 microg/ml, and 0.5 microg/ml, respectively. Those of ampicillin, piperacillin, ceftriaxone, cefotaxime, meropenem, and panipenem against H. influenzae were >128 microg/ml, >128 microg/ml, 0.25 microg/mL, 1 microg/ml, 0.12 microg/ml, and 0.5 g/ml, respectively. It is suggest that the minimum bactricidal concentration

  1. Conjugation of Polyphosphoester and Antimicrobial Peptide for Enhanced Bactericidal Activity and Biocompatibility.

    Science.gov (United States)

    Pranantyo, Dicky; Xu, Li Qun; Kang, En-Tang; Mya, Mya Khin; Chan-Park, Mary B

    2016-12-12

    Enhancing the bactericidal activity and moderating the toxicity are two important challenges in the design of upcoming antimicrobial compounds. Herein, antimicrobial macromolecules were developed by conjugating CysHHC10 peptide and polyphosphoester for the modulation of microbiocidal activity and biocompatibility. The conjugation was carried out via thiol-yne "click" chemistry between the cysteine terminal of the peptide and the pendant propargyl moieties of the polyphosphoester. The bactericidal efficacy of the polyphosphoester-peptide conjugates were investigated by microbial growth inhibition toward the Gram-positive and Gram-negative bacteria. On the basis of peptide mass fraction, the polyphosphoester-peptide conjugates exhibited lower values of minimum inhibitory concentration than that of the free peptide. The polyphosphoester-peptide conjugates also exhibited ultralow hemolytic characteristic at a concentration of 4000 μg/mL, indicating significant improvement of erythrocytes compatibility as compared to the free peptide that readily caused lysis of 50% of red blood cells at 1000 μg/mL. Cytotoxicity of the polyphosphoester-peptide conjugates toward 3T3 fibroblast cells was also reduced in comparison to that of the free peptide. Conjugation of the polyphosphoester thus improves the bactericidal efficacy and biocompatibility of the antimicrobial peptide.

  2. Preparation and bactericide activity of gallic acid stabilized gold nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Moreno-Alvarez, S. A. [UASLP, Doctorado Institucional en Ingenieria y Ciencia de Materiales (Mexico); Martinez-Castanon, G. A., E-mail: mtzcastanon@fciencias.uaslp.m [UASLP, Maestria en Ciencias Odontologicas, Facultad de Estomatologia (Mexico); Nino-Martinez, N. [UASLP, Facultad de Ciencias (Mexico); Reyes-Macias, J. F.; Patino-Marin, N.; Loyola-Rodriguez, J. P. [UASLP, Maestria en Ciencias Odontologicas, Facultad de Estomatologia (Mexico); Ruiz, Facundo [UASLP, Facultad de Ciencias (Mexico)

    2010-10-15

    In this work, gold nanoparticles with three different sizes (13.7, 39.4, and 76.7 nm) were prepared using a simple aqueous method with gallic acid as the reducing and stabilizing agent, the different sizes were obtained varying some experimental parameters as the pH of the reaction and the amount of the gallic acid. The prepared nanoparticles were characterized using X-ray diffraction, transmission electron microscopy, dynamic light scattering, and UV-Vis spectroscopy. Samples were identified as elemental gold and present spherical morphology, a narrow size distribution and good stabilization according to TEM and DLS results. The antibacterial activity of this gallic acid stabilized gold nanoparticles against S. mutans (the etiologic agent of dental caries) was assessed using a microdilution method obtaining a minimum inhibitory concentration of 12.31, 12.31, and 49.25 {mu}g/mL for 13.7, 39.4, and 76.7 nm gold nanoparticles, respectively. The antibacterial assay showed that gold nanoparticles prepared in this work present a bactericide activity by a synergistic action with gallic acid. The MIC found for this nanoparticles are much lower than those reported for mixtures of gold nanoparticles and antibiotics.

  3. Preparation and bactericide activity of gallic acid stabilized gold nanoparticles

    International Nuclear Information System (INIS)

    Moreno-Alvarez, S. A.; Martinez-Castanon, G. A.; Nino-Martinez, N.; Reyes-Macias, J. F.; Patino-Marin, N.; Loyola-Rodriguez, J. P.; Ruiz, Facundo

    2010-01-01

    In this work, gold nanoparticles with three different sizes (13.7, 39.4, and 76.7 nm) were prepared using a simple aqueous method with gallic acid as the reducing and stabilizing agent, the different sizes were obtained varying some experimental parameters as the pH of the reaction and the amount of the gallic acid. The prepared nanoparticles were characterized using X-ray diffraction, transmission electron microscopy, dynamic light scattering, and UV-Vis spectroscopy. Samples were identified as elemental gold and present spherical morphology, a narrow size distribution and good stabilization according to TEM and DLS results. The antibacterial activity of this gallic acid stabilized gold nanoparticles against S. mutans (the etiologic agent of dental caries) was assessed using a microdilution method obtaining a minimum inhibitory concentration of 12.31, 12.31, and 49.25 μg/mL for 13.7, 39.4, and 76.7 nm gold nanoparticles, respectively. The antibacterial assay showed that gold nanoparticles prepared in this work present a bactericide activity by a synergistic action with gallic acid. The MIC found for this nanoparticles are much lower than those reported for mixtures of gold nanoparticles and antibiotics.

  4. Bactericidal activity of titanium dioxide ultraviolet-induced films.

    Science.gov (United States)

    Pleskova, S N; Golubeva, I S; Verevkin, Y K

    2016-02-01

    TiO2 films are used as a self-sterilization surface due to their property to form reactive oxygen species (ROS) when irradiated with ultraviolet light. These ROS attack bacteria and kill them. We present a new way to enhance the bactericidal activity of TiO2-films: formation of nanopores on the surface by four-beam high-power laser irradiation. Such surfaces have significantly higher antibacterial activity as compared to conventional TiO2 surfaces after 15 and 60min of UV irradiation. Study of the bacterial cell morphology by atomic force microscopy after 60min irradiation showed that Staphylococcus aureus 956 and Escherichia coli 321-5 undergo significant morphological changes. S. aureus assume atypical elongated shapes after UV treatment alone and swollen forms with protrusions after UV treatment on TiO2 surface. E. coli exhibit oval or round forms after UV treatment alone, and round forms with small protrusions, and destroyed cells after incubation under UV on the TiO2 film. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Influence of pulmonary surfactant on in vitro bactericidal activities of amoxicillin, ceftazidime, and tobramycin

    NARCIS (Netherlands)

    A. van 't Veen (Annemarie); J.W. Mouton (Johan); D.A.M.P.J. Gommers (Diederik); J.A.J.W. Kluytmans (Jan); P. Dekkers; B.F. Lachmann (Burkhard)

    1995-01-01

    textabstractThe influence of a natural pulmonary surfactant on antibiotic activity was investigated to assess the possible use of exogenous surfactant as a vehicle for antibiotic delivery to the lung. The influence of surfactant on the bactericidal activity of

  6. The Siderophore Product Ornibactin Is Required for the Bactericidal Activity of Burkholderia contaminans MS14.

    Science.gov (United States)

    Deng, Peng; Foxfire, Adam; Xu, Jianhong; Baird, Sonya M; Jia, Jiayuan; Delgado, Keren H; Shin, Ronald; Smith, Leif; Lu, Shi-En

    2017-04-15

    Burkholderia contaminans MS14 was isolated from soil in Mississippi. When it is cultivated on nutrient broth-yeast extract agar, the colonies exhibit bactericidal activity against a wide range of plant-pathogenic bacteria. A bacteriostatic compound with siderophore activity was successfully purified and was determined by nuclear magnetic resonance spectroscopy to be ornibactin. Isolation of the bactericidal compound has not yet been achieved; therefore, the exact nature of the bactericidal compound is still unknown. During an attempt to isolate the bactericidal compound, an interesting relationship between the production of ornibactin and the bactericidal activity of MS14 was characterized. Transposon mutagenesis resulted in two strains that lost bactericidal activity, with insertional mutations in a nonribosomal peptide synthetase (NRPS) gene for ornibactin biosynthesis and a luxR family transcriptional regulatory gene. Coculture of these two mutant strains resulted in restoration of the bactericidal activity. Furthermore, the addition of ornibactin to the NRPS mutant restored the bactericidal phenotype. It has been demonstrated that, in MS14, ornibactin has an alternative function, aside from iron sequestration. Comparison of the ornibactin biosynthesis genes in Burkholderia species shows diversity among the regulatory elements, while the gene products for ornibactin synthesis are conserved. This is an interesting observation, given that ornibactin is thought to have the same defined function within Burkholderia species. Ornibactin is produced by most Burkholderia species, and its role in regulating the production of secondary metabolites should be investigated. IMPORTANCE Identification of the antibacterial product from strain MS14 is not the key feature of this study. We present a series of experiments that demonstrate that ornibactin is directly involved in the bactericidal phenotype of MS14. This observation provides evidence for an alternative function for

  7. Serum bactericidal activity as indicator of innate immunity in pacu Piaractus mesopotamicus (Holmberg, 1887

    Directory of Open Access Journals (Sweden)

    J.D. Biller-Takahashi

    2013-12-01

    Full Text Available The immune system of teleost fish has mechanisms responsible for the defense against bacteria through protective proteins in several tissues. The protein action can be evaluated by serum bactericidal activity and this is an important tool to analyze the immune system. Pacu, Piaractus mesopotamicus, is one of the most important fish in national aquaculture. However there is a lack of studies on its immune responses. In order to standardize and assess the accuracy of the serum bactericidal activity assay, fish were briefly challenged with Aeromonas hydrophila and sampled one week after the challenge. The bacterial infection increased the concentration of protective proteins, resulting in a decrease of colony-forming unit values expressed as well as an enhanced serum bactericidal activity. The protocol showed a reliable assay, appropriate to determine the serum bactericidal activity of pacu in the present experimental conditions.

  8. Improvement of deficient natural killer activity and delayed bactericidal activity by a thiol proteinase inhibitor, E-64-d, in leukocytes from Chediak-Higashi syndrome patients in vitro.

    Science.gov (United States)

    Tanabe, Fuminori; Kasai, Hirotake; He, Limin; Kin, Tomohiro; Fujikado, Takashi; Kumamoto, Toshihide; Hara, Toshiro; Iwata, Tsutomu; Ito, Masahiko

    2009-03-01

    We previously reported that administration of a potent calpain inhibitor, E-64-d, which protects protein kinase C (PKC) from proteolysis, in a mouse model of Chediak-Higashi syndrome (CHS) (beige mice), decreases its susceptibility to Staphylococcus aureus infection. In the present study, we examined the in vitro effect of E-64-d on both deficient natural killer (NK) and delayed bactericidal activities of leukocytes from six CHS patients. Our results showed that pretreatment of peripheral blood mononuclear cells (PBMCs) obtained from CHS patients with E-64-d (1 microg/ml) significantly enhanced NK activity against K562 cells. The delayed bactericidal activity of polymorphonuclear cells (PMNs) against S. aureus also showed marked improvement. This was recovered to almost normal levels when PMNs were pretreated with E-64-d (1 microg/ml). On the other hand, the same concentration of E-64-d did not affect either the NK or bactericidal activity of normal controls. In addition, we confirmed that following E-64-d treatment, the abnormal down-regulation of PKC activity after concanavalin A (Con A) stimulation was eliminated in PBMCs obtained from CHS patients. To examine whether PKC is involved in the NK cell-mediated cytolysis and bactericidal activity of PMNs, two potent PKC inhibitors, chelerythrin and GO6976, were used. We found that chelerythrin inhibits NK activity of normal PBMCs in a dose-dependent manner, and GO6976 inhibits NK activity at doses that inhibit Ca(2+)-dependent PKC isozymes. These inhibitors also suppressed the bactericidal activity of PMNs against S. aureus. Taken together, our findings suggested that E-64-d improved the compromised NK and bactericidal activity of leukocytes from CHS patients by reversing the down-regulation of PKC activity.

  9. Container type and bactericidal activity of human milk during refrigerated storage.

    Science.gov (United States)

    Takci, Sahin; Gulmez, Dolunay; Yigit, Sule; Dogan, Ozlem; Hascelik, Gulsen

    2013-08-01

    Refrigeration of human milk has been recommended for its short-term storage. It has been shown that some nutritional, immunological, and bioactive properties and bactericidal activity of human milk can be altered during refrigeration. Pyrex bottles and polyethylene bags are 2 commonly used containers for human milk storage. The aim of this study was to compare the association between storage container type on the bactericidal activity of human milk for different durations of refrigeration (fresh, and at 24 and 48 hours). Forty-four samples of human milk were collected from 22 lactating mothers. Two samples of breast milk (approximately 10 mL each) were obtained by manual expression from each mother. One was collected directly into sterile Pyrex bottles and the other into polyethylene bags. One mL of human milk from each container was processed immediately after arrival to the laboratory. The remaining human milk was kept in the Pyrex and polyethylene containers at 4°C until analysis at 24 and 48 hours. The bactericidal activity of each sample was studied. A strain of Escherichia coli ATCC 25922 was used to determine the bactericidal effect of human milk. Bactericidal activity was significantly reduced in milk samples stored in polyethylene bags compared to those stored in Pyrex bottles when milk samples were stored at 4°C for 24 and 48 hours (P bactericidal activity against E coli.

  10. Retinoid agonist Am80-enhanced neutrophil bactericidal activity arising from granulopoiesis in vitro and in a neutropenic mouse model

    Science.gov (United States)

    Ding, Wanjing; Shimada, Hiroyuki; Li, Lin; Mittal, Rahul; Zhang, Xiaokun; Shudo, Koichi; He, Qiaojun; Prasadarao, Nemani V.

    2013-01-01

    Despite advances in the therapeutic use of recombinant granulocyte colony-stimulating factor (G-CSF) to promote granulopoiesis of human hematopoietic stem cells (HSCs), neutropenia remains one of the most serious complications of cancer chemotherapy. We discovered that retinoid agonist Am80 (tamibarotene) is more potent than G-CSF in coordinating neutrophil differentiation and immunity development. Am80-induced neutrophils (AINs) either in vitro or in neutropenic mouse model displayed strong bactericidal activities, similar to those of human peripheral blood neutrophils (PBNs) or mouse peripheral blood neutrophils (MPBNs) but markedly greater than did G-CSF–induced neutrophils (GINs). In contrast to GINs but similar to PBNs, the enhanced bacterial killing by AINs accompanied both better granule maturation and greater coexpression of CD66 antigen with the integrin β2 subunit CD18. Consistently, anti-CD18 antibody neutralized Am80-induced bactericidal activities of AINs. These studies demonstrate that Am80 is more effective than G-CSF in promoting neutrophil differentiation and bactericidal activities, probably through coordinating the functional interaction of CD66 with CD18 to enhance the development of neutrophil immunity during granulopoiesis. Our findings herein suggest a molecular rationale for developing new therapy against neutropenia using Am80 as a cost-effective treatment option. PMID:23243275

  11. Bactericidal activity of penicillin, ceftriaxone, gentamicin and daptomycin alone and in combination against Aerococcus urinae.

    Science.gov (United States)

    Hirzel, Cédric; Hirzberger, Lea; Furrer, Hansjakob; Endimiani, Andrea

    2016-09-01

    Aerococcus urinae can cause severe infections (bacteraemia and endocarditis) that are associated with high mortality. However, data on the bactericidal and synergistic activity for clinically implemented antibiotics are scarce. Time-kill analyses were performed on two clinical isolates (AU1 and AU2) and the reference strain ATCC 700306 for penicillin (PG), ceftriaxone (CRO), gentamicin (GEN), daptomycin (DAP) and their combinations. AU1 and AU2 were CRO-resistant (MICs, 2 µg/mL) and ATCC 700306 was high-level GEN-resistant (MIC, 512 µg/mL), whereas all strains were PG- and DAP-susceptible (MICs, ≤0.125 and ≤1 µg/mL, respectively). CFU counts were determined at various time points from 0 to 48 h. All experiments were performed at 0.5×, 1×, 2× and 4× MIC. PG and CRO were not bactericidal for all strains, whereas DAP exhibited bactericidal activity at all concentrations for AU2 and ATCC 700306. The combination of PG or CRO with GEN was bactericidal for AU1 and AU2 at antibiotic concentrations ≥1× MIC. Bactericidal synergism was detected for PG or CRO combined with GEN in the two clinical isolates. PG plus CRO showed non-bactericidal synergism for ATCC 700306. DAP with GEN was synergistic at 1× MIC for AU1, whereas the killing activity of DAP was too pronounced to detect potential synergism in AU2. The combination of PG or CRO with GEN is synergistic and bactericidal. Moreover, these in vitro data suggest that DAP may represent a potential bactericidal treatment alternative against A. urinae. This finding could be important for the treatment of patients with a β-lactam allergy or renal insufficiency. Copyright © 2016 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

  12. Lactobacillus Proteins Are Associated with the Bactericidal Activity against E. coli of Female Genital Tract Secretions

    Science.gov (United States)

    Kalyoussef, Sabah; Nieves, Edward; Dinerman, Ellen; Carpenter, Colleen; Shankar, Viswanathan; Oh, Jamie; Burd, Berta; Angeletti, Ruth H.; Buckheit, Karen W.; Fredricks, David N.; Madan, Rebecca P.; Keller, Marla J.; Herold, Betsy C.

    2012-01-01

    Background Female genital tract secretions are bactericidal for Escherichia (E.) coli ex vivo. However, the intersubject variability and molecules that contribute to this activity have not been defined. Methods The bactericidal activity and concentration of immune mediators in cervicovaginal lavage (CVL) collected from 99 healthy women were determined. Results CVL reduced the number of E. coli colonies by 68% [−26, 100] (median [range]). CVL were active against laboratory and clinical isolates of E. coli, but were inactive against Lactobacillus species. Bactericidal activity correlated with the concentration of protein recovered (p90% inhibitory activity (active) and two withbactericidal for E. coli. Conclusion Both host and commensal microbiota proteins contribute to mucosal defense. Identification of these proteins will facilitate the development of strategies to maintain a healthy vaginal microbiome and prevent colonization with pathogenic bacteria such as E. coli that increase the risk for urinary tract infections, preterm labor and perinatal infection. PMID:23185346

  13. Maternal intrapartum antibiotic treatment continues to exert a bactericidal effect on the umbilical cord and peripheral venous blood of newborn infants.

    Science.gov (United States)

    Hershkovich-Shporen, C; Bardenstein, R; Blickstein, I; Shinwell, E S; Flidel-Rimon, O

    2017-11-01

    It is unclear whether maternal intrapartum antibiotic treatment (IAT) continues to exert a bactericidal effect on common pathogens in neonates. We studied the in vitro bactericidal effect of IAT on the cord and peripheral venous blood of newborn infants. Umbilical cord and peripheral venous blood from newborn infants born at Kaplan Medical Center, Israel, from April to October 2014 were studied for serum bactericidal titres against Group B Streptococcus (GBS) and Escherichia coli (E. coli) strains. We studied 60 samples of umbilical cord blood and 18 samples of peripheral venous blood from 60 newborn infants whose mothers received IAT. The controls were 10 samples of cord blood from mothers without IAT. Cord blood exerted a bactericidal effect against 98% of GBS isolates but only 8% of E.coli isolates. Peripheral blood exerted a bactericidal effect against GBS in 94% of cases, but not against E. coli. No bactericidal effect was seen in the blood from the controls. We found a continued bactericidal effect of umbilical cord blood and neonatal peripheral blood from newborn infants of IAT-treated mothers, mainly against GBS, but rarely against E. Coli. These findings may assist clinicians treating at-risk infants exposed to IAT. ©2017 Foundation Acta Paediatrica. Published by John Wiley & Sons Ltd.

  14. The behavior of active bactericidal and antifungal coating under visible light irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Gang; Zhang, Xiaodong; Zhao, Yan; Su, Haijia, E-mail: suhj@mail.buct.edu.cn; Tan, Tianwei

    2014-02-15

    In the present paper, the novel active bactericidal and antifungal coatings (ABAC) have been prepared through the immobilization of Fe-doped TiO{sub 2} (anatase) with chitosan. The characterization of ABAC using optical microscope imaging, SEM, AFM and FTIR shows that the Fe doped TiO{sub 2} is embedded into the chitosan coating with favorable dispersion through the hydrogen bonds interaction between chitosan molecules and TiO{sub 2}. The contact angle measurement demonstrated the hydrophilicity of ABAC (θ = 34.5 ± 4.1°). The bactericidal activity of ABAC has been evaluated by inactivating three different test strains: Escherichia coli, Candida albicans and Aspergillus niger which illustrates the apparently higher bactericidal ability than chitosan, Fe-TiO{sub 2} and chitosan/TiO{sub 2} (pure) under visible light irradiation and its bactericidal activity is lasting for at least 24 h. ABAC showed rapid and efficient antibacterial ability for the three tested strains and its antibacterial ratio in 2 h for E. coli, C. albicans and A. niger was 99.9%, 97.0% and 95.0%, respectively. The prepared chitosan/TiO{sub 2} composite emulsion shows favorable storage stability and can be stored up to 1 year without losing its bactericidal activity. ABAC is a low-cost and eco-friendly antibacterial coating products and promising for domestic, medical and industrial applications.

  15. Processing, characterization, and bactericidal activity of undoped and silver-doped vanadium oxides

    International Nuclear Information System (INIS)

    Tousley, M.E.; Wren, A.W.; Towler, M.R.; Mellott, N.P.

    2012-01-01

    Vanadium oxide (V) and silver-doped vanadium oxide (Ag-V) powders were prepared via sol–gel processing. Structural evolution and bactericidal activity was examined as a function of temperature ranging from 250, 350, 450 and 550 °C. Powders were characterized using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and Raman spectroscopy. Results from all techniques showed vanadium pentoxide (V 2 O 5 ) is the predominant phase regardless of heat treatment temperature or the addition of silver (Ag). XRD analysis suggests Ag is present as AgCl in samples heat treated to 250, 350, and 450 °C and as AgV 6 O 15 at 550 °C. Bactericidal activity was evaluated against Escherichia coli using the agar disk diffusion method considering both Ag-V and undoped, V powders. While the addition of Ag significantly increased bactericidal properties, the specific Ag valency, or crystal structure and morphology formed at higher temperatures, had little effect on functionality. -- Highlights: ► Vanadium and silver-doped vanadium oxide powders were prepared via sol–gel. ► Powders were characterized using advanced, complementary structural techniques. ► Bactericidal activity was evaluated against E. coli. ► Both vanadium and silver doped vanadium oxide show bactericidal activity.

  16. Anti-adherence and bactericidal activity of sphingolipids against Streptococcus mutans

    NARCIS (Netherlands)

    Cukkemane, N.; Bikker, F.J.; Nazmi, K.; Brand, H.S.; Sotres, J.; Lindh, L.; Arnebrant, T.; Veerman, E.C.I.

    2015-01-01

    This study evaluated the anti-biofilm activity of sphingosine, phytosphingosine (PHS), and sphinganine for: (i) anti-adherence activity on hydroxyapatite (HA) surfaces; and (ii) bactericidal activity on different Streptococcus mutans phenotypes (i.e. planktonic cells and cells from a disrupted

  17. BACTERICIDAL COATINGS ON TEXTILES FOR REMEDIATION OF INTERMICROBE ACTIVITY (BaCTeRIA) SUMMARY REPORT

    Science.gov (United States)

    2017-07-07

    TEXTILES FOR REMEDIATION OF INTERMICROBE ACTIVITY ( BaCTeRIA ) SUMMARY REPORT by Tobyn A. Branck Courtney M. Cowell Jennifer M. Rego and...October 2011 – September 2015 4. TITLE AND SUBTITLE BACTERICIDAL COATINGS ON TEXTILES FOR REMEDIATION OF INTERMICROBE ACTIVITY ( BaCTeRIA ) SUMMARY REPORT...ANTHRAX PURIFICATION BACILLUS ANTHRACIS ENVIRONMENTAL ISOLATES BACTERIA BACTERIOCINS TARGETED ACTIVITY

  18. Morphology-dependent bactericidal activities of Ag/CeO2 catalysts against Escherichia coli.

    Science.gov (United States)

    Wang, Lian; He, Hong; Yu, Yunbo; Sun, Li; Liu, Sijin; Zhang, Changbin; He, Lian

    2014-06-01

    Silver-loaded CeO2 nanomaterials (Ag/CeO2) including Ag/CeO2 nanorods, nanocubes, nanoparticles were prepared with hydrothermal and impregnation methods. Catalytic inactivation of Escherichia coli with Ag/CeO2 catalysts through the formation of reactive oxygen species (ROS) was investigated. For comparison purposes, the bactericidal activities of CeO2 nanorods, nanocubes and nanoparticles were also studied. There was a 3-4 log order improvement in the inactivation of E. coli with Ag/CeO2 catalysts compared with CeO2 catalysts. Temperature-programmed reduction of H2 showed that Ag/CeO2 catalysts had higher catalytic oxidation ability than CeO2 catalysts, which was the reason for that Ag/CeO2 catalysts exhibited stronger bactericidal activities than CeO2 catalysts. Further, the bactericidal activities of CeO2 and Ag/CeO2 depend on their shapes. Results of 5,5-dimethyl-1-pyrroline-N-oxide spin-trapping measurements by electron spin resonance and addition of catalase as a scavenger indicated the formation of OH, O2(-), and H2O2, which caused the obvious bactericidal activity of catalysts. The stronger chemical bond between Ag and CeO2 nanorods led to lower Ag(+) elution concentrations. The toxicity of Ag(+) eluted from the catalysts did not play an important role during the bactericidal process. Experimental results also indicated that Ag/CeO2 induced the production of intracellular ROS and disruption of the cell wall and cell membrane. A possible production mechanism of ROS and bactericidal mechanism of catalytic oxidation were proposed. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Staphylococcus aureus SaeR/S-Regulated Factors Decrease Monocyte-Derived Tumor Necrosis Factor-α to Reduce Neutrophil Bactericidal Activity.

    Science.gov (United States)

    Sward, Eli W; Fones, Elizabeth M; Spaan, Russel R; Pallister, Kyler B; Haller, Brandon L; Guerra, Fermin E; Zurek, Oliwia W; Nygaard, Tyler K; Voyich, Jovanka M

    2018-03-05

    The ability of Staphylococcus aureus to evade killing by human neutrophils significantly contributes to disease progression. In this study, we characterize an influential role for the S. aureus SaeR/S 2-component gene regulatory system in suppressing monocyte production of tumor necrosis factor alpha (TNF-α) to subsequently influence human neutrophil priming. Using flow cytometry and TNF-α specific enzyme-linked immunosorbent assays we identify the primary cellular source of TNF-α in human blood and in purified peripheral blood mononuclear cells (PBMCs) during interaction with USA300 and an isogenic saeR/S deletion mutant (USA300∆saeR/S). Assays with conditioned media from USA300 and USA300∆saeR/S exposed PBMCs were used to investigate priming on neutrophil bactericidal activity. TNF-α production from monocytes was significantly reduced following challenge with USA300 compared to USA300∆saeR/S. We observed that priming of neutrophils using conditioned medium from peripheral blood mononuclear cells stimulated with USA300∆saeR/S significantly increased neutrophil bactericidal activity against USA300 relative to unprimed neutrophils and neutrophils primed with USA300 conditioned medium. The increased neutrophil bactericidal activity was associated with enhanced reactive oxygen species production that was significantly influenced by elevated TNF-α concentrations. Our findings identify an immune evasion strategy used by S. aureus to impede neutrophil priming and subsequent bactericidal activity.

  20. Observation of Serum Bactericidal Activity of Brucella abortus RB51 OMPs Combined with Brucella abortus RB51 Live Vaccine

    Directory of Open Access Journals (Sweden)

    Fahime Gholizadeh

    2013-06-01

    Full Text Available Background & objectives: vaccination is vital against brucellosis. Although current vaccines have low efficiency, some cell wall compartments such as Outer Membrane Proteins could be used as an immunogenic candidate in vaccine development. By this mean, our aim in this study was to evaluate the humoral immunity of the combination of Brucella abortus RB51 OMPs with the Brucella abortus RB51 live attenuated vaccine, by Serum Bactericidal Acitivity test. Materials and Methods: In this project, first Brucella abortus RB51 was cultivated in brucella agar. The OMPs were extracted by Sodium N-Lauryl Sarcosinate method, then added to the RB51 live attenuated vaccine. Immunization was done by injection of the vaccine to mice and rabbits. The blood was drawn on days 0, 15,30, and 45 from the rabbits and the sera were seperated. Brucella abortus 544 was also injected as challenge. Spleen colony count was also performed. Results: The data from Serum Bactericidal Assay has showed, there was a very high Humoral immunity and response as a bactericidal titre of the serum against Rb51 Live vaccine. There was a significant decrease of colonies in the group vaccinated with the combined vaccine in the Spleen colony count test. Statistical analysis of groups variances showed a significant difference between groups (P<0.05.Conclusions: The Serum Bactericidal Assay results showed despite previous studies, both the combine and live vaccine are capable to stimulate the Humoral immunity. greater activity of combined vaccine to boost the humoral activity might be due to the synergistic effect of this vaccine.

  1. Bactericidal Activity of Octenidine to Various Genospecies of Borrelia burgdorferi, Sensu Lato Spirochetes in Vitro and in Vivo.

    Science.gov (United States)

    Tylewska-Wierzbanowska, Stanisława; Rogulska, Urszula; Lewandowska, Grażyna; Chmielewski, Tomasz

    2017-07-06

    The aim of our studies was to invent a reliable method for detection of the bactericidal activity of disinfectants against Borrelia burgdorferi in suspension (in vitro) and in cell line cultures (in vivo). In the suspension method, 0.01% octenidine at 20°C and 35°C was bactericidal to Borrelia afzeli; Borrelia garini, B. burgdorferi sensu stricto after 5 minutes treatment. Increase of the temperature to 35°C speed up the bactericidal effect to 1 minute. The bactericidal action of octenidine towards B. burgdorferi spirochetes growing in fibroblasts was less effective and needed a longer time to kill them than in the suspension.

  2. Characterization and Activity of an Immobilized Antimicrobial Peptide Containing Bactericidal PEG-Hydrogel

    NARCIS (Netherlands)

    Cleophas, Rik T. C.; Sjollema, Jelmer; Busscher, Henk J.; Kruijtzer, John A. W.; Liskamp, Rob M. J.

    A single step immobilization-polymerization strategy of a highly active antimicrobial peptide into a soft hydrogel network on a poly(ethylene terephthalate) surface using thiol-ene chemistry is described. The bactericidal hydrogel was molecularly characterized via Coomassie and Lowry assay protein

  3. Characterization and activity of an immobilized antimicrobial peptide containing bactericidal PEG-hydrogel

    NARCIS (Netherlands)

    Cleophas, Rik T C|info:eu-repo/dai/nl/341566578; Sjollema, Jelmer; Busscher, Henk J; Kruijtzer, John A W|info:eu-repo/dai/nl/15207449X; Liskamp, Rob M J|info:eu-repo/dai/nl/069091315

    2014-01-01

    A single step immobilization-polymerization strategy of a highly active antimicrobial peptide into a soft hydrogel network on a poly(ethylene terephthalate) surface using thiol-ene chemistry is described. The bactericidal hydrogel was molecularly characterized via Coomassie and Lowry assay protein

  4. Increased bactericidal activity of colistin on Pseudomonas aeruginosa biofilms in anaerobic conditions

    DEFF Research Database (Denmark)

    Kolpen, Mette; Appeldorff, Cecilie F.; Brandt, Sarah

    2016-01-01

    that production of OH˙may not contribute significantly to the bactericidal activity of colistin on P. aeruginosa biofilm. Thus, we investigated the effect of colistin treatment on biofilm of wild-type PAO1, a catalase-deficient mutant (katA) and a colistin-resistant CF isolate cultured in microtiter plates...

  5. Effect of Human Immunodeficiency Virus Infection on Plasma Bactericidal Activity against Salmonella enterica Serovar Typhimurium

    Science.gov (United States)

    Trebicka, Estela; Shanmugam, Nanda Kumar N.; Mikhailova, Anastassia; Alter, Galit

    2014-01-01

    Individuals with human immunodeficiency virus (HIV) infection have increased susceptibility to invasive disease caused by Salmonella enterica serovar Typhimurium. Studies from Africa have suggested that this susceptibility is related in part to the development of a high level of lipopolysaccharide (LPS)-specific IgG that is able to inhibit the killing of S. Typhimurium by bactericidal antibodies in healthy individuals. To explore this issue further, we examined the bactericidal activity against S. Typhimurium using serum and plasma samples from healthy controls and various clinical subgroups of HIV-infected adults in the United States. We found that the bactericidal activity in the samples from HIV-positive elite controllers was comparable to that from healthy individuals, whereas it was significantly reduced in HIV-positive viremic controllers and untreated chronic progressors. As demonstrated previously for healthy controls, the bactericidal activity of the plasma from the elite controllers was inhibited by preincubation with S. Typhimurium LPS, suggesting that it was mediated by anti-LPS antibodies. S. Typhimurium LPS-specific IgG was significantly reduced in all subgroups of HIV-infected individuals. Interestingly, and in contrast to the healthy controls, plasma from all HIV-positive subgroups inhibited in vitro killing of S. Typhimurium by plasma from a healthy individual. Our results, together with the findings from Africa, suggest that multiple mechanisms may be involved in the HIV-induced dysregulation of humoral immunity to S. Typhimurium. PMID:25121777

  6. Sequestration of nanoparticles by an EPS matrix reduces the particle-specific bactericidal activity

    Science.gov (United States)

    Wang, Qian; Kang, Fuxing; Gao, Yanzheng; Mao, Xuewei; Hu, Xiaojie

    2016-02-01

    Most artificial nanomaterials are known to exhibit broad-spectrum bactericidal activity; however, the defence mechanisms that bacteria use based on extracellular polymeric substances (EPS) to detoxify nanoparticles (NPs) are not well known. We ruled out the possibility of ion-specific bactericidal activity by showing the lack of equivalent dissolved zinc and silicon toxicity and determined the particle-specific toxicity of ZnO and SiO2 nanoparticles (ZnONPs/SiO2NPs) through dialysis isolation experiments. Surprisingly, the manipulation of the E. coli EPS (i.e., no EPS manipulation or EPS removal by sonication/centrifugation) showed that their particle-specific bactericidal activity could be antagonized by NP-EPS sequestration. The survival rates of pristine E. coli (no EPS manipulation) reached 65% (ZnONPs, 500 mg L-1) and 79% (SiO2NPs, 500 mg L-1), whereas survival rates following EPS removal by sonication/centrifugation were 11% and 63%, respectively. Transmission electron microscopy (TEM) combined with fluorescence micro-titration analysis and Fourier-transform infrared spectroscopy (FTIR) showed that protein-like substances (N-H and C-N in amide II) and secondary carbonyl groups (C=O) in the carboxylic acids of EPS acted as important binding sites that were involved in NP sequestration. Accordingly, the amount and composition of EPS produced by bacteria have important implications for the bactericidal efficacy and potential environmental effects of NPs.

  7. Bactericidal activity of propylene glycol, glycerine, polyethylene glycol 400, and polyethylene glycol 1000 against selected microorganisms.

    Science.gov (United States)

    Nalawade, Triveni Mohan; Bhat, Kishore; Sogi, Suma H P

    2015-01-01

    The aim of the present study was to evaluate the bactericidal activity of propylene glycol, glycerine, polyethylene glycol 400 (PEG 400), and polyethylene glycol 1000 (PEG 1000) against selected microorganisms in vitro. Five vehicles, namely propylene glycol, glycerine, PEG 400, PEG 1000, and combination of propylene glycol with PEG 400, were tested for their bactericidal activity. The minimum bactericidal concentration was noted against four standard strains of organisms, i.e. Streptococcus mutans American Type Culture Collection (ATCC) 25175, Streptococcus mutans ATCC 12598, Enterococcus faecalis ATCC 35550, and Escherichia coli ATCC 25922, using broth dilution assay. Successful endodontic therapy depends upon thorough disinfection of root canals. In some refractory cases, routine endodontic therapy is not sufficient, so intracanal medicaments are used for proper disinfection of canals. Intracanal medicaments are dispensed with vehicles which aid in increased diffusion through the dentinal tubules and improve their efficacy. Among the various vehicles used, glycerine is easily available, whereas others like propylene glycol and polyethylene glycol have to be procured from appropriate sources. Also, these vehicles, being viscous, aid in sustained release of the medicaments and improve their handling properties. The most commonly used intracanal medicaments like calcium hydroxide are ineffective on many microorganisms, while most of the other medicaments like MTAD (Mixture of Tetracycline, an Acid, and a Detergent) and Triple Antibiotic Paste (TAP) consist of antibiotics which can lead to development of antibiotic resistance among microorganisms. Thus, in order to use safer and equally effective intracanal medicaments, newer alternatives like chlorhexidine gluconate, ozonized water, etc., are being explored. Similarly, the five vehicles mentioned above are being tested for their antimicrobial activity in this study. All vehicles exhibited bactericidal activity at

  8. Bactericidal and endotoxin neutralizing activity of a peptide derived from Limulus antilipopolysaccharide factor.

    Science.gov (United States)

    Weiss, C A; Wasiluk, K R; Kellogg, T A; Dunn, D L

    2000-08-01

    Release of lipopolysaccharide (endotoxin, LPS) is a critical inciting event in the development of sepsis syndrome due to gram-negative bacteria, and mortality associated with this entity remains approximately 40%. Limulus anti-LPS factor (LALF) is a naturally occurring horseshoe crab derived protein that, unlike antibiotics, is both bactericidal for gram-negative bacteria and capable of neutralizing LPS. We hypothesized that a peptide derived from the active domain of LALF (LALF #28-54) would exhibit potent biologic activity similar to that of LALF itself and could potentially be useful as a therapeutic agent. The effects of LALF, synthetic peptide LALF #28-54, polymyxin B (PmB), and a biologically inactive synthetic peptide were examined in several models. In vitro bactericidal activity was determined against Pseudomonas aeruginosa, and LPS-neutralizing capacity was determined via inhibition of LPS-induced tumor necrosis factor-alpha (TNF-alpha) secretion by RAW 264.7 cells. In vivo biologic activity was determined via pretreatment following which P aeruginosa endotoxemia or bacteremia was induced; serum TNF-alpha levels, bacterial clearance, and survival were assessed. LALF and LALF #28-54 exhibited potent in vitro bactericidal and LPS-neutralizing activity comparable to PmB (P bacterial clearance similar to that observed for LALF (P .1). These data demonstrate that peptide LALF #28-54 retained the LPS-neutralizing and bactericidal biologic activity of LALF but failed to protect during overwhelming P aeruginosa bacteremia, perhaps due to short serum half-life.

  9. Tomatidine and analog FC04-100 possess bactericidal activities against Listeria, Bacillus and Staphylococcus spp.

    Science.gov (United States)

    Guay, Isabelle; Boulanger, Simon; Isabelle, Charles; Brouillette, Eric; Chagnon, Félix; Bouarab, Kamal; Marsault, Eric; Malouin, François

    2018-02-13

    Tomatidine (TO) is a plant steroidal alkaloid that possesses an antibacterial activity against the small colony variants (SCVs) of Staphylococcus aureus. We report here the spectrum of activity of TO against other species of the Bacillales and the improved antibacterial activity of a chemically-modified TO derivative (FC04-100) against Listeria monocytogenes and antibiotic multi-resistant S. aureus (MRSA), two notoriously difficult-to-kill microorganisms. Bacillus and Listeria SCVs were isolated using a gentamicin selection pressure. Minimal inhibitory concentrations (MICs) of TO and FC04-100 were determined by a broth microdilution technique. The bactericidal activity of TO and FC04-100 used alone or in combination with an aminoglycoside against planktonic bacteria was determined in broth or against bacteria embedded in pre-formed biofilms by using the Calgary Biofilm Device. Killing of intracellular SCVs was determined in a model with polarized pulmonary cells. TO showed a bactericidal activity against SCVs of Staphylococcus aureus, Bacillus cereus, B. subtilis and Listeria monocytogenes with MICs of 0.03-0.12 μg/mL. The combination of an aminoglycoside and TO generated an antibacterial synergy against their normal phenotype. In contrast to TO, which has no relevant activity by itself against Bacillales of the normal phenotype (MIC > 64 μg/mL), the TO analog FC04-100 showed a MIC of 8-32 μg/mL. Furthermore, FC04-100 showed a strong bactericidal activity against L. monocytogenes SCVs in kill kinetics experiments, while TO did not. The addition of FC04-100 (4 μg/mL) to a cefalexin:kanamycin (3:2) combination improved the activity of the combination by 32 fold against cefalexin and kanamycin-resistant MRSA strains. In combination with gentamicin, FC04-100 also exhibited a strong bactericidal activity against biofilm-embedded S. aureus. Also, FC04-100 and TO showed comparable intracellular killing of S. aureus SCVs. Chemical modifications of TO allowed

  10. Structural effect of quaternary ammonium chitin derivatives on their bactericidal activity and specificity.

    Science.gov (United States)

    Morkaew, Tirut; Pinyakong, Onruthai; Tachaboonyakiat, Wanpen

    2017-08-01

    The effect of the quaternary ammonium chitin structure on the bactericidal activity and specificity against Escherichia coli and Staphylococcus aureus was investigated. Quaternary ammonium chitins were synthesized by the separate acylation of chitin (CT) with carboxymethyl trimethylammonium chloride (CMA), 3-carboxypropyl trimethylammonium chloride (CPA) and N-dodecyl-N,N-(dimethylammonio)butyrate (DDMAB). The successful acylation was confirmed by newly formed ester linkage. All three derivatives had a higher surface charge than chitin due to the additional positively charged quaternary ammonium groups. The N-short alkyl substituent (methyl) of CTCMA and CTCPA increased the hydrophilicity whilst the N-long alkyl substituent (dodecyl) of CTDDMAB increased the hydrophobicity compared to chitin. Chitin did not exhibit any bactericidal activity, while CTCMA and CTCPA completely killed E. coli and S. aureus in 30 and 60min, respectively, and CTDDMAB completely killed S. aureus in 10min but did not kill E. coli after a 2-h exposure. Therefore, the N-short alkyl substituent was more effective for killing E. coli and the N-long alkyl substituent conferred specific bactericidal activity against S. aureus. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Antibacterial activity against Ralstonia solanacearum of phenolic constituents isolated from dragon's blood.

    Science.gov (United States)

    Wang, Hui; Luo, Ying; Dai, Haofu; Mei, Wenli

    2013-03-01

    Ralstonia solanacearum is a worldwide and devastating plant pathogen infesting over 200 host species. Synthetic bactericides against the pathogen have only achieved limited success and always cause both crop contamination and environmental pollution. However, natural bactericides are effective for protecting cultivated crops from destruction by disease, without the adverse effects of chemical bactericides. In this paper, fifteen phenolic constituents from dragon's blood were screened for their antimicrobial activity against Ralstonia solanacearum, and all exhibited inhibitory activity. These compounds are potential leading compounds for the development of bactericides against wilt diseases caused by Ralstonia solanacearum.

  12. Bactericidal activity and post-antibiotic effect of ozenoxacin against Propionibacterium acnes.

    Science.gov (United States)

    Kanayama, Shoji; Okamoto, Kazuaki; Ikeda, Fumiaki; Ishii, Ritsuko; Matsumoto, Tatsumi; Hayashi, Naoki; Gotoh, Naomasa

    2017-06-01

    Ozenoxacin, a novel non-fluorinated topical quinolone, is used for the treatment of acne vulgaris in Japan. We investigated bactericidal activity and post-antibiotic effect (PAE) of ozenoxacin against Propionibacterium acnes, a major causative bacterium of acne vulgaris. The minimum inhibitory concentrations (MICs) of ozenoxacin against 3 levofloxacin-susceptible strains (MIC of levofloxacin; ≤4 μg/mL) and 3 levofloxacin-resistant strains (MIC of levofloxacin; ≥8 μg/mL) ranged from 0.03 to 0.06 μg/mL and from 0.25 to 0.5 μg/mL, respectively. These MICs of ozenoxacin were almost the same or lower than nadifloxacin and clindamycin. The minimum bactericidal concentrations (MBCs) of ozenoxacin against the levofloxacin-susceptible and -resistant strains were from 0.06 to 8 μg/mL and from 0.5 to 4 μg/mL, respectively. These MBCs were lower than those of nadifloxacin and clindamycin. In time-kill assay, ozenoxacin at 1/4, 1 and 4 times the respective MIC against both levofloxacin-susceptible and -resistant strains showed a concentration-dependent bactericidal activity. Ozenoxacin at 4 times the MICs against the levofloxacin-susceptible strains showed more potent and more rapid onset of bactericidal activity compared to nadifloxacin and clindamycin at 4 times the respective MICs. The PAEs of ozenoxacin at 4 times the MICs against the levofloxacin-susceptible strains were from 3.3 to 17.1 h, which were almost the same or longer than nadifloxacin and clindamycin. In contrast, the PAEs were hardly induced by any antimicrobial agents against the levofloxacin-resistant strains. The present findings suggest that ozenoxacin has a potent bactericidal activity against both levofloxacin-susceptible and -resistant P. acnes, and a long-lasting PAE against levofloxacin-susceptible P. acnes. Copyright © 2017 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

  13. Superhydrophobic and White Light-Activated Bactericidal Surface through a Simple Coating.

    Science.gov (United States)

    Hwang, Gi Byoung; Patir, Adnan; Allan, Elaine; Nair, Sean P; Parkin, Ivan P

    2017-08-30

    Bacterial adhesion and proliferation on surfaces are a challenge in medical and industrial fields. Here, a simple one-step technique is reported to fabricate self-cleaning and bactericidal surfaces. White, blue, and violet paints were produced using titanium dioxide nanoparticles, 1H,1H,2H,2H-perfluorooctyltriethoxysilane, crystal violet, toluidine Blue O, and ethanol solution. All of the painted surfaces showed superhydrophobicity in air, and even after hexadecane oil contamination, they retained water repellency and self-cleaning properties. In an assay of bacterial adhesion, significant reductions (>99.8%) in the number of adherent bacteria were observed for all the painted surfaces. In bactericidal tests, the painted surfaces not only demonstrated bactericidal activity against Staphylococcus aureus and Escherichia coli in the dark but also induced very potent photosensitization (>4.4 log reduction in the number of viable bacteria on the violet painted surface) under white light illumination. The technique that we developed here is general and can be used on a wide range of substrates such as paper, glass, polymers, and others.

  14. Phytosynthesis of Silver Nanoparticles Using Myrtus communis L. Leaf Extract and Investigation of Bactericidal Activity

    Science.gov (United States)

    Ajdari, M. R.; Tondro, G. H.; Sattarahmady, N.; Parsa, A.; Heli, H.

    2017-12-01

    Silver nanoparticles have been synthesized using only Myrtus communis L. leaf extract by a facile procedure without other reagents. The extract played the roles of both reducing and capping agent. The nanoparticles were characterized using field-emission scanning microscopy, and remained stable for at least 3 weeks. Antibacterial activity of the nanoparticles was evaluated toward Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, Staphylococcus aureus, methicillin-resistant Staphylococcus aureus, and Enterococcus faecalis based on inhibition zone disk diffusion assays. The minimum inhibitory and bactericidal concentrations of the nanoparticles were obtained. Mechanisms for the antibacterial activity were proposed.

  15. Contribution of the complement Membrane Attack Complex to the bactericidal activity of human serum.

    Science.gov (United States)

    Berends, Evelien T M; Mohan, Sarbani; Miellet, Willem R; Ruyken, Maartje; Rooijakkers, Suzan H M

    2015-06-01

    Direct killing of Gram-negative bacteria by serum is usually attributed to the Membrane Attack Complex (MAC) that is assembled upon activation of the complement system. In serum bactericidal assays, the activity of the MAC is usually blocked by a relatively unspecific method in which certain heat-labile complement components are inactivated at 56°C. The goal of this study was to re-evaluate MAC-driven lysis towards various Gram-negative bacteria. Instead of using heat-treatment, we included the highly specific C5 cleavage inhibitor OmCI to specifically block the formation of the MAC. Using a C5 conversion analysis tool, we monitored the efficacy of the inhibitor during the incubations. Our findings indicate that 'serum-sensitive' bacteria are not necessarily killed by the MAC. Other heat-labile serum factors can contribute to serum bactericidal activity. These unidentified factors are most potent at serum concentrations of 10% and higher. Furthermore, we also find that some bacteria can be killed by the MAC at a slower rate. Our data demonstrate the requirement for the use of specific inhibitors in serum bactericidal assays and revealed that the classification of serum-sensitive and resistant strains needs re-evaluation. Moreover, it is important to determine bacterial viability at multiple time intervals to differentiate serum susceptibility between bacterial species. In conclusion, these data provide new insights into bacterial killing by the humoral immune system and may guide future vaccine development studies for the treatment of pathogenic serum-resistant bacteria. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Superior bactericidal activity of SDS capped silver nanoparticles: Synthesis and characterization

    Energy Technology Data Exchange (ETDEWEB)

    Kora, Aruna Jyothi, E-mail: koramaganti@gmail.com [National Centre for Compositional Characterisation of Materials (CCCM), Bhabha Atomic Research Centre, ECIL PO, Hyderabad-500 062 (India); Manjusha, R.; Arunachalam, J. [National Centre for Compositional Characterisation of Materials (CCCM), Bhabha Atomic Research Centre, ECIL PO, Hyderabad-500 062 (India)

    2009-08-31

    Silver nanoparticles were synthesized through UV photo-reduction of silver nitrate aqueous solution, containing ethanol and sodium dodecyl sulfate (SDS) using an UV digester equipped with high pressure mercury lamp of 500 W. The synthesized nanoparticles were characterized by UV-vis spectroscopy (UV-vis), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The formation of silver nanoparticles was confirmed from the appearance of surface plasmon absorption maxima at 418 nm. TEM showed the spherical nanoparticles with size in 23-67 nm (average 45 {+-} 10 nm). The silver nanoparticles were stable for more than 8 months. The antibacterial activity of these SDS capped silver nanoparticles was tested using Pseudomonas aeruginosa as a model strain for gram-negative bacteria. SDS capped silver nanoparticles exhibit a much higher bactericidal activity compared to silver nanoparticles capped with other capping agents. Even at a low silver nanoparticle concentration of 5 {mu}g/ml, complete inhibition of 10{sup 7} colony forming units (CFU) was achieved with SDS capped silver nanoparticles. This concentration is much lower than the values reported by other authors. This enhanced bactericidal activity is attributed to much efficient transport of silver nanoparticles by SDS to the outer membrane of cell wall compared to the other capping agents and have a better interaction of nanoparticles with the cell.

  17. Time-kill determination of the bactericidal activity of telavancin and vancomycin against clinical methicillin-resistant Staphylococcus aureus isolates from cancer patients.

    Science.gov (United States)

    Rolston, Kenneth Vi; Wang, Weiqun; Nesher, Lior; Smith, Jordan R; Rybak, Michael J; Prince, Randall A

    2017-04-01

    The bactericidal activity of vancomycin and telavancin was compared against 4 clinical methicillin-resistant Staphylococcus aureus isolates recently recovered from cancer patients, using minimum bactericidal concentration (MBC):MIC ratios and time-kill studies. All 4 isolates were susceptible to both agents based on individual MIC values. The 2 methodologies for assessing bactericidal activity produced variable results. Telavancin appeared to have somewhat better bactericidal activity than vancomycin based on narrower MBC:MIC ratios. However, based on the results of the time-kill studies, neither agent demonstrated reliable bactericidal activity (defined as a ≥3 log 10 reduction of the starting inoculum at the end of 24hours) against these organisms. These findings might be of some therapeutic importance in certain clinical settings and/or specific patient populations (such as febrile neutropenic patients) in whom potent bactericidal activity is either desired or preferred. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Green Synthesis of Silver Nanoparticles and Their Bactericidal and Antimycotic Activities against Oral Microbes

    Directory of Open Access Journals (Sweden)

    Osvelia E. Rodríguez-Luis

    2016-01-01

    Full Text Available Nanotechnology is a new discipline with huge applications including medicine and pharmacology industries. Although several methods and reducing agents have been employed to synthesize silver nanoparticles, reactive chemicals promote toxicity and nondesired effects on the human and biological systems. The objective of this work was to synthesize silver nanoparticles from Glycyrrhiza glabra and Amphipterygium adstringens extracts and determine their bactericidal and antimycotic activities against Enterococcus faecalis and Candida albicans growth, respectively. 1 and 10 mM silver nitrate were mixed with an extract of Glycyrrhiza glabra and Amphipterygium adstringens. Green silver nanoparticles (AgNPs were characterized by TEM, Vis-NIR, FTIR, fluorescence, DLS, TGA, and X-ray diffraction (XRD analysis. Bactericidal and antimycotic activities of AgNPs were determined by Kirby and Bauer method and cell viability MTT assays. AgNPs showed a spherical shape and average size of 9 nm if prepared with Glycyrrhiza glabra extract and 3 nm if prepared with Amphipterygium adstringens extract. AgNPs inhibited the bacterial and fungal growth as was expected, without a significant cytotoxic effect on human epithelial cells. Altogether, these results strongly suggest that AgNPs could be an interesting option to control oral biofilms.

  19. CXC Chemokines Exhibit Bactericidal Activity against Multidrug-Resistant Gram-Negative Pathogens

    Directory of Open Access Journals (Sweden)

    Matthew A. Crawford

    2017-11-01

    Full Text Available The continued rise and spread of antimicrobial resistance among bacterial pathogens pose a serious challenge to global health. Countering antimicrobial-resistant pathogens requires a multifaceted effort that includes the discovery of novel therapeutic approaches. Here, we establish the capacity of the human CXC chemokines CXCL9 and CXCL10 to kill multidrug-resistant Gram-negative bacteria, including New Delhi metallo-beta-lactamase-1-producing Klebsiella pneumoniae and colistin-resistant members of the family Enterobacteriaceae that harbor the mobile colistin resistance protein MCR-1 and thus possess phosphoethanolamine-modified lipid A. Colistin-resistant K. pneumoniae isolates affected by genetic mutation of the PmrA/PmrB two-component system, a chromosomally encoded regulator of lipopolysaccharide modification, and containing 4-amino-4-deoxy-l-arabinose-modified lipid A were also found to be susceptible to chemokine-mediated antimicrobial activity. However, loss of PhoP/PhoQ autoregulatory control, caused by disruption of the gene encoding the negative regulator MgrB, limited the bactericidal effects of CXCL9 and CXCL10 in a variable, strain-specific manner. Cumulatively, these findings provide mechanistic insight into chemokine-mediated antimicrobial activity, highlight disparities amongst determinants of colistin resistance, and suggest that chemokine-mediated bactericidal effects merit additional investigation as a therapeutic avenue for treating infections caused by multidrug-resistant pathogens.

  20. A Simple, Reproducible, Inexpensive, Yet Old-Fashioned Method for Determining Phagocytic and Bactericidal Activities of Macrophages.

    Science.gov (United States)

    Kaneko, Masakazu; Emoto, Yoshiko; Emoto, Masashi

    2016-03-01

    Macrophages (Mφ) play a pivotal role in the protection system by recognizing and eliminating invading pathogenic bacteria. Phagocytosis and the killing of invading bacteria are major effector functions of Mφ. Although the phagocytic and bactericidal activities of Mφ have been analyzed via several methods using a light microscope, a fluorescence microscope, or a fluorescence-activated cell sorter, expensive materials and equipment are usually required, and the methods are rather complicated. Moreover, it is impossible to determine both the phagocytic and bactericidal activities of Mφ simultaneously using these methods. In this review, we describe a simple, reproducible, inexpensive, yet old-fashioned method (antibiotic protection assay) for determining the phagocytic and bactericidal activities of Mφ.

  1. Disinfection with gaseous formaldehyde. Fifth Part: Influence of albumin, mucin and blood on the bactericidal and sporicidal effectiveness.

    Science.gov (United States)

    Casella, M L; Schmidt-Lorenz, W

    1989-10-01

    The influence of 0.1% peptone, 0.2% albumin, 1% mucin solutions and whole human blood on the inactivation of Staphylococcus aureus ATCC 6538 and spores of Bacillus subtilis var. niger DSM 675 was determined. The bactericidal and sporicidal effectiveness of 0.75, 1.5 and 3.2 mg HCHO l-1 air at temperatures of 35, 40, 45 degrees C and a relative humidity (RH) of 90% decreased in the following order of loading substances: peptone, albumin, mucin and blood. The calculated D-values of the microorganisms suspended and dried in 0.1% petone and in 0.2% albumin after exposure to 3.2 mg HCHO l-1 air at 40 degrees C and a relative humidity of approximately 90% were in both suspensions 1.9 min for S. aureus and 6.1 and 7.3 min respectively for B. subtilis spores. Under the same exposure conditions but with an addition of 1% mucin D-values of 2.5 min and 7.7 min for S. aureus and B. subtilis spores respectively were found. In the presence of blood, D-values of 12.3 and 18.3 min were obtained under the same conditions for S. aureus and B. subtilis spores respectively. Thus the suspension in blood caused a 2-fold increase in D-value compared to the other substances. The nature of the anticoagulant in the whole blood did not cause much difference in the inactivation of B.subtilis spores. Decreasing concentrations of blood caused an increase in sensitivity of B.subtilis spores to gaseous formaldehyde, whereby diluting blood 1:6 reduced the D-value from 23.9 min to only 7.1 min.

  2. Smart Biointerface with Photoswitched Functions between Bactericidal Activity and Bacteria-Releasing Ability.

    Science.gov (United States)

    Wei, Ting; Zhan, Wenjun; Yu, Qian; Chen, Hong

    2017-08-09

    Smart biointerfaces with capability to regulate cell-surface interactions in response to external stimuli are of great interest for both fundamental research and practical applications. Smart surfaces with "ON/OFF" switchability for a single function such as cell attachment/detachment are well-known and useful, but the ability to switch between two different functions may be seen as the next level of "smart". In this work reported, a smart supramolecular surface capable of switching functions reversibly between bactericidal activity and bacteria-releasing ability in response to UV-visible light is developed. This platform is composed of surface-containing azobenzene (Azo) groups and a biocidal β-cyclodextrin derivative conjugated with seven quaternary ammonium salt groups (CD-QAS). The surface-immobilized Azo groups in trans form can specially incorporate CD-QAS to achieve a strongly bactericidal surface that kill more than 90% attached bacteria. On irradiation with UV light, the Azo groups switch to cis form, resulting in the dissociation of the Azo/CD-QAS inclusion complex and release of dead bacteria from the surface. After the kill-and-release cycle, the surface can be easily regenerated for reuse by irradiation with visible light and reincorporation of fresh CD-QAS. The use of supramolecular chemistry represents a promising approach to the realization of smart, multifunctional surfaces, and has the potential to be applied to diverse materials and devices in the biomedical field.

  3. Bactericidal activity of bio-synthesized silver nanoparticles against human pathogenic bacteria

    International Nuclear Information System (INIS)

    Abalkhil, Tarad Abdulaziz; Alharbi, Sulaiman Ali; Salmen, Saleh Hussein; Wainwright, Milton

    2017-01-01

    Green synthesis is an attractive and eco-friendly approach to generate potent antibacterial silver nanoparticles (Ag-NPs). Such particles have long been used to fight bacteria and represent a promising tool to overcome the emergence of antibiotic-resistant bacteria. In this study, green synthesis of Ag-NPs was attempted using plant extracts of Aloe vera, Portulaca oleracea and Cynodon dactylon. The identity and size of Ag-NPs was characterized by ultraviolet–visible spectrophotometer and scanning electron microscopy. Monodispersed Ag-NPs were produced with a range of different sizes based on the plant extract used. The bactericidal activity of Ag-NPs against a number of human pathogenic bacteria was determined using the disc diffusion method. The results showed that Gram positive bacteria were more susceptible than Gram negative ones to these antibacterial agents. The minimum inhibitory concentration was determined using the 96- well plate method. Finally, the mechanism by which Ag-NPs affect bacteria was investigated by SEM analysis. Bacteria treated with Ag-NPs were seen to undergo shrinkage and to lose their viability. This study provides evidence for a cheap and effective method for synthesizing potent bactericidal Ag-NPs and demonstrates their effectiveness against human pathogenic bacteria

  4. Correlation and in vitro mechanism of bactericidal activity on E. coli with whey protein isolate during ultrasonic treatment.

    Science.gov (United States)

    Liu, Liyan; Xu, Ruirui; Li, Lin; Li, Bing; Zhang, Xia; Zhang, Ximei; Xu, Zhenbo

    2017-12-24

    This study aimed to investigate correlation and in vitro mechanism of bactericidal activity on E. coli with whey protein isolate (WPI) during ultrasonic treatment. The structural changes of WPI under ultrasonic field were studied by amino-acid analyzer, circular dichroism, SDS-PAGE, and spectrophotometer. With the increasing of WPI concentration added during ultrasonic treatment, the survival rate of E. coli increased. The influence of WPI on bactericidal activity under ultrasonic treatment might due to the change of tertiary and higher level structures, not by the primary structure, and had little relation with secondary structure. The influence of WPI on bactericidal activity during ultrasonic treatment might due to the change of the tertiary structure and higher level structures. Copyright © 2017. Published by Elsevier Ltd.

  5. Impact of solution chemistry on the properties and bactericidal activity of silver nanoparticles decorated on superabsorbent cryogels.

    Science.gov (United States)

    Loo, Siew-Leng; Krantz, William B; Hu, Xiao; Fane, Anthony G; Lim, Teik-Thye

    2016-01-01

    This study investigated the effects of dissolved organic matter (DOM) and various electrolytes commonly found in environmental aqueous matrices on the physicochemical properties and bactericidal efficacy of silver nanoparticles (AgNPs), which are immobilized on cryogels (or PSA/AgNP cryogel). The AgNPs in the PSA/AgNP cryogel that were exposed to different media underwent morphological transformation in terms of particle size and structure. In addition, the presence of DOM and electrolytes increased the release of dissolved Ag. The biological uptake of Ag species (determined as the total Ag in exposed cells) increased in the presence of DOM, but decreased in the presence of electrolytes. The presence of electrolytes did not result in any significant reduction in the bactericidal activity. Although an initial increase of the DOM to 2.5 mg-C L(-1) attenuated the bactericidal efficacy of the immobilized AgNPs, an increase in the DOM concentration beyond 5 mg-C L(-1) enhanced the bactericidal efficacy. This study found that the bactericidal activity of the immobilized AgNPs is less sensitive to the solution chemistry relative to the free AgNPs. This suggests that immobilizing the AgNPs in a supporting material is a good strategy to preserve their efficacy for disinfection in various aqueous matrices. Copyright © 2015 Elsevier Inc. All rights reserved.

  6. Bactericidal Activity and Synergy Studies of Peptide AP-CECT7121 Against Multi-resistant Bacteria Isolated from Human and Animal Soft Tissue Infections.

    Science.gov (United States)

    Delpech, Gastón; Bistoletti, Mariana; Ceci, Mónica; Lissarrague, Sabina; Bruni, Sergio Sánchez; Sparo, Mónica

    2017-09-01

    AP-CECT7121 is an antimicrobial peptide, produced by Enterococcus faecalis CECT7121, with bactericidal activity against Gram-positive bacteria. The aim of this study was to evaluate the bactericidal activity of AP-CECT7121, alone and with gentamicin, against multi-resistant bacteria isolated from human and animals with soft tissue infections. During the period 2014-2015, bacterial strains producing human and animal soft tissue infections were studied. Samples from patients attended at a general hospital and cattle from four dairies in the Province of Buenos Aires (Argentina) were included. Twenty-two methicillin-resistant Staphylococcus aureus (11, human blood samples; 11, cow milk) and five vancomycin-resistant Ent. faecium strains isolated from four mastitic dairy cows were tested. AP-CECT7121 (12 mg/L) potency was assessed by time-kill curves alone or with sub-inhibitory concentrations of gentamicin. All staphylococcal strains were susceptible to gentamicin; enterococci did not show high-level gentamicin resistance. Colony counts were carried out at 0, 2, 4, 8, and 24 h of incubation. AP-CECT7121 showed bactericidal activity against all the enterococcal strains. In addition, AP-CECT7121 had a bactericidal effect on most staphylococci (16/22). Early AP-CECT7121/gentamicin synergy (4-8 h) for all staphylococci was detected. At 24 h, synergy (19/22) and indifference (3/22) were observed. Synergy with gentamicin was detected for staphylococci. AP-CECT7121 constitutes an attractive candidate for its use as a natural therapeutic tool for the treatment of infections produced by multi-resistant Staph. aureus and vancomycin-resistant Ent. faecium isolated from humans and animals.

  7. Bactericidal activity of human lysozyme, muramidase-inactive lysozyme, and cationic polypeptides against Streptococcus sanguis and Streptococcus faecalis: inhibition by chitin oligosaccharides.

    Science.gov (United States)

    Laible, N J; Germaine, G R

    1985-01-01

    The basis of the bactericidal activity of human lysozyme against Streptococcus sanguis was studied. Experiments were designed to evaluate the role of lysozyme muramidase activity in its bactericidal potency. Inactivation of the muramidase activity of lysozyme was achieved by reduction of essential disulfides with dithiothreitol (DTT) or by incubation with the chitin oligosaccharides chitotriose and chitobiose. Muramidase-inactive lysozyme, prepared by reduction with DTT, was equal in bactericidal potency to native lysozyme. Solutions of native chicken egg white lysozyme and human lysozyme exhibited equal bactericidal potency yet differed ca. fourfold with respect to lytic (muramidase) activity. The above results suggested that the bactericidal activity of lysozyme is not dependent upon muramidase activity. Chitotriose and chitobiose were found to inhibit both lytic and bactericidal activities of lysozyme. The bactericidal activity of muramidase-inactive lysozyme (reduction with DTT) was also inhibited by chitotriose and chitobiose. Further investigations demonstrated that chitotriose and chitobiose were also potent inhibitors of the bactericidal activity of the cationic homopolypeptides poly-L-arginine and poly-D-lysine. These latter results suggested that the essential bactericidal property of lysozyme was its extreme cationic nature and that some bacterial endogenous activities, inhibitable by chitotriose and chitobiose, were essential for expression of the bactericidal activity of either native or muramidase-inactive lysozyme or of the cationic homopolypeptides. Experiments with Streptococcus faecalis whole cells, cell walls, and crude autolysin preparations implicated endogenous autolytic muramidases as the bacterial targets of chitotriose and chitobiose. The essentially identical responses of S. sanguis and S. faecalis to chitotriose in bactericidal assays with muramidase-inactive lysozyme and polylysine suggested that muramidase-like enzymes exist in S

  8. Coleus aromaticus leaf extract mediated synthesis of silver nanoparticles and its bactericidal activity

    Science.gov (United States)

    Vanaja, Mahendran; Annadurai, Gurusamy

    2013-06-01

    The utilization of various plant resources for the biosynthesis of metallic nanoparticles is called green nanotechnology, and it does not utilize any harmful chemical protocols. The present study reports the plant-mediated synthesis of silver nanoparticles using the plant leaf extract of Coleus aromaticus, which acts as a reducing and capping agent. The silver nanoparticles were characterized by ultraviolet visible spectroscopy, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and the size of the silver nanoparticles is 44 nm. The bactericidal activity of the silver nanoparticles was carried out by disc diffusion method that showed high toxicity against Bacillus subtilis and Klebsiella planticola. Biosynthesis of silver nanoparticles by using plant resources is an eco-friendly, reliable process and suitable for large-scale production. Moreover, it is easy to handle and a rapid process when compared to chemical, physical, and microbe-mediated synthesis process.

  9. Importance of Antibodies to Lipopolysaccharide in Natural and Vaccine-Induced Serum Bactericidal Activity against Neisseria meningitidis Group B▿†

    Science.gov (United States)

    Schmiel, Deborah H.; Moran, Elizabeth E.; Keiser, Paul B.; Brandt, Brenda L.; Zollinger, Wendell D.

    2011-01-01

    Analysis of the specificity of bactericidal antibodies in normal, convalescent, and postvaccination human sera is important in understanding human immunity to meningococcal infections and can aid in the design of an effective group B vaccine. A collection of human sera, including group C and group B convalescent-phase sera, normal sera with naturally occurring cross-reactive bactericidal activity, and some postvaccination sera, was analyzed to determine the specificity of cross-reactive bactericidal antibodies. Analysis of human sera using a bactericidal antibody depletion assay demonstrated that a significant portion of the bactericidal activity could be removed by purified lipopolysaccharide (LPS). LPS homologous to that expressed on the bactericidal test strain was most effective, but partial depletion by heterologous LPS suggested the presence of antibodies with various degrees of cross-reactivity. Binding of anti-L3,7 LPS bactericidal antibodies was affected by modification of the core structure, suggesting that these functional antibodies recognized epitopes consisting of both core structures and lacto-N-neotetraose (LNnT). When the target strain was grown with 5′-cytidinemonophospho-N-acetylneuraminic acid (CMP-NANA) to increase LPS sialylation, convalescent-phase serum bactericidal titers were decreased by only 2- to 4-fold, and most remaining bactericidal activity was still depleted by LPS. Highly sialylated LPS was ineffective in depleting bactericidal antibodies. We conclude that natural infections caused by strains expressing L3,7 LPS induce persistent, protective bactericidal antibodies and appear to be directed against nonsialylated bacterial epitopes. Additionally, subsets of these bactericidal antibodies are cross-reactive, binding to several different LPS immunotypes, which is a useful characteristic for an effective group B meningococcal vaccine antigen. PMID:21768280

  10. Comparison of bacteriostatic and bactericidal activity of 13 essential oils against strains with varying sensitivity to antibiotics.

    Science.gov (United States)

    Mayaud, L; Carricajo, A; Zhiri, A; Aubert, G

    2008-09-01

    To compare the bacteriostatic and bactericidal activity of 13 chemotyped essential oils (EO) on 65 bacteria with varying sensitivity to antibiotics. Fifty-five bacterial strains were tested with two methods used for evaluation of antimicrobial activity (CLSI recommendations): the agar dilution method and the time-killing curve method. EO containing aldehydes (Cinnamomum verum bark and Cymbopogon citratus), phenols (Origanum compactum, Trachyspermum ammi, Thymus satureioides, Eugenia caryophyllus and Cinnamomum verum leaf) showed the highest antimicrobial activity with minimum inhibitory concentration (MIC) or = 10% (v/v). Against P. aeruginosa, only C. verum bark and O. compactum presented MIC < or =2% (v/v). Cinnamomum verum bark, O. compactum, T. satureioides, C. verum leaf and M. alternifolia were bactericidal against Staphylococcus aureus and Escherichia coli at concentrations ranging from to 0.31% to 10% (v/v) after 1 h of contact. Cinnamomum verum bark and O. compactum were bactericidal against P. aeruginosa within 5 min at concentrations <2% (v/v). Cinnamomum verum bark had the highest antimicrobial activity, particularly against resistant strains. Bacteriostatic and bactericidal activity of EO on nosocomial antibiotic-resistant strains.

  11. The Effect of Long-Term Storage on the Physiochemical and Bactericidal Properties of Electrochemically Activated Solutions

    Science.gov (United States)

    Robinson, Gareth; Thorn, Robin; Reynolds, Darren

    2013-01-01

    Electrochemically activated solutions (ECAS) are generated by electrolysis of NaCl solutions, and demonstrate broad spectrum antimicrobial activity and high environmental compatibility. The biocidal efficacy of ECAS at the point of production is widely reported in the literature, as are its credentials as a “green biocide.” Acidic ECAS are considered most effective as biocides at the point of production and ill suited for extended storage. Acidic ECAS samples were stored at 4 °C and 20 °C in glass and polystyrene containers for 398 days, and tested for free chlorine, pH, ORP and bactericidal activity throughout. ORP and free chlorine (mg/L) in stored ECAS declined over time, declining at the fastest rate when stored at 20 °C in polystyrene and at the slowest rate when stored at 4 °C in glass. Bactericidal efficacy was also affected by storage and ECAS failed to produce a 5 log10 reduction on five occasions when stored at 20 °C. pH remained stable throughout the storage period. This study represents the longest storage evaluation of the physiochemical parameters and bactericidal efficacy of acidic ECAS within the published literature and reveals that acidic ECAS retain useful bactericidal activity for in excess of 12 months, widening potential applications. PMID:23263673

  12. Shape-dependent bactericidal activity of copper oxide nanoparticle mediated by DNA and membrane damage

    Energy Technology Data Exchange (ETDEWEB)

    Laha, Dipranjan; Pramanik, Arindam [Department of Life Science and Biotechnology, Jadavpur University, 188, Raja S C Mallick Road, Kolkata 700032 (India); Laskar, Aparna [CSIR-Indian Institute of Chemical Biology, Kolkata 700032 (India); Jana, Madhurya [Department of Life Science and Biotechnology, Jadavpur University, 188, Raja S C Mallick Road, Kolkata 700032 (India); Pramanik, Panchanan [Department of Chemistry, Indian Institute of Technology, Kharagpur 721302 (India); Karmakar, Parimal, E-mail: pkarmakar_28@yahoo.co.in [Department of Life Science and Biotechnology, Jadavpur University, 188, Raja S C Mallick Road, Kolkata 700032 (India)

    2014-11-15

    Highlights: • Spherical and sheet shaped copper oxide nanoparticles were synthesized. • Physical characterizations of these nanoparticles were done by TEM, DLS, XRD, FTIR. • They showed shape dependent antibacterial activity on different bacterial strain. • They induced both membrane damage and ROS mediated DNA damage in bacteria. - Abstract: In this work, we synthesized spherical and sheet shaped copper oxide nanoparticles and their physical characterizations were done by the X-ray diffraction, fourier transform infrared spectroscopy, transmission electron microscopy and dynamic light scattering. The antibacterial activity of these nanoparticles was determined on both gram positive and gram negative bacterial. Spherical shaped copper oxide nanoparticles showed more antibacterial property on gram positive bacteria where as sheet shaped copper oxide nanoparticles are more active on gram negative bacteria. We also demonstrated that copper oxide nanoparticles produced reactive oxygen species in both gram negative and gram positive bacteria. Furthermore, they induced membrane damage as determined by atomic force microscopy and scanning electron microscopy. Thus production of and membrane damage are major mechanisms of the bactericidal activity of these copper oxide nanoparticles. Finally it was concluded that antibacterial activity of nanoparticles depend on physicochemical properties of copper oxide nanoparticles and bacterial strain.

  13. Shape-dependent bactericidal activity of copper oxide nanoparticle mediated by DNA and membrane damage

    International Nuclear Information System (INIS)

    Laha, Dipranjan; Pramanik, Arindam; Laskar, Aparna; Jana, Madhurya; Pramanik, Panchanan; Karmakar, Parimal

    2014-01-01

    Highlights: • Spherical and sheet shaped copper oxide nanoparticles were synthesized. • Physical characterizations of these nanoparticles were done by TEM, DLS, XRD, FTIR. • They showed shape dependent antibacterial activity on different bacterial strain. • They induced both membrane damage and ROS mediated DNA damage in bacteria. - Abstract: In this work, we synthesized spherical and sheet shaped copper oxide nanoparticles and their physical characterizations were done by the X-ray diffraction, fourier transform infrared spectroscopy, transmission electron microscopy and dynamic light scattering. The antibacterial activity of these nanoparticles was determined on both gram positive and gram negative bacterial. Spherical shaped copper oxide nanoparticles showed more antibacterial property on gram positive bacteria where as sheet shaped copper oxide nanoparticles are more active on gram negative bacteria. We also demonstrated that copper oxide nanoparticles produced reactive oxygen species in both gram negative and gram positive bacteria. Furthermore, they induced membrane damage as determined by atomic force microscopy and scanning electron microscopy. Thus production of and membrane damage are major mechanisms of the bactericidal activity of these copper oxide nanoparticles. Finally it was concluded that antibacterial activity of nanoparticles depend on physicochemical properties of copper oxide nanoparticles and bacterial strain

  14. Design, synthesis and structure-bactericidal activity relationships of novel 9-oxime ketolides and reductive epimers of acylides.

    Science.gov (United States)

    Tian, Jing-Chao; Han, Xu; Lv, Wei; Li, Ya-Xin; Wang, Hui; Fan, Bing-Zhi; Cushman, Mark; Liang, Jian-Hua

    2017-04-01

    Erythromycin was long viewed as a bacteriostatic agent. The erythromycin derivatives, 9-oxime ketolides have a species-specific bactericidal profile. Among them, the 3'-allyl version of the 9-oxime ketolide 1 (Ar=3-quinolyl; 17a) is bactericidal against Streptococcus pneumoniae and Streptococcus pyogenes. In contrast, the 2-fluoro analogs of 1, 13a (Ar=6-quinolyl), 13b (Ar=3-quinolyl) and 24a (Ar=4-isoquinolyl), show bactericidal activities against S. pneumoniae, Staphylococcus aureus and Moraxella catarrhalis, while the 2-fluoro analogs 13c (Ar=3-aminopyridyl) and 24b (Ar=3-carbamoylpyridyl) are only bactericidal against S. pneumoniae and Haemophilus influenzae. Reduction of the ketolides led to novel epiacylides, the 3-O-epimers of the acylides. Alteration of linker length (30b vs. 30a), 2-fluorination (33 vs. 30a) and incorporation of additional spacers at the 9-oxime or 6-OH (35, 40 vs. 30a) did not restore the epiacylides back to be as active as the acylide 31. Molecular docking suggested that epimerization at the 3-position reshapes the orientation of the 3-O-sidechain and leads to considerably weaker binding with bacterial ribosomes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Biofilm-forming activity of bacteria isolated from toilet bowl biofilms and the bactericidal activity of disinfectants against the isolates.

    Science.gov (United States)

    Mori, Miho; Gomi, Mitsuhiro; Matsumune, Norihiko; Niizeki, Kazuma; Sakagami, Yoshikazu

    2013-01-01

    To evaluate the sanitary conditions of toilets, the bacterial counts of the toilet bowl biofilms in 5 Kansai area and 11 Kansai and Kanto area homes in Japan were measured in winter and summer seasons, respectively. Isolates (128 strains) were identified by analyzing 16S ribosomal RNA sequences. The number of colonies and bacterial species from biofilms sampled in winter tended to be higher and lower, respectively, than those in summer. Moreover, the composition of bacterial communities in summer and winter samples differed considerably. In summer samples, biofilms in Kansai and Kanto areas were dominated by Blastomonas sp. and Mycobacterium sp., respectively. Methylobacterium sp. was detected in all toilet bowl biofilms except for one sample. Methylobacterium sp. constituted the major presence in biofilms along with Brevundimonas sp., Sphingomonas sp., and/or Pseudomonas sp. The composition ratio of the sum of their genera was 88.0 from 42.9% of the total bacterial flora. The biofilm formation abilities of 128 isolates were investigated, and results suggested that Methylobacterium sp. and Sphingomonas sp. were involved in biofilm formation in toilet bowls. The biofilm formation of a mixed bacteria system that included bacteria with the highest biofilm-forming ability in a winter sample was greater than mixture without such bacteria. This result suggests that isolates possessing a high biofilm-forming activity are involved in the biofilm formation in the actual toilet bowl. A bactericidal test against 25 strains indicated that the bactericidal activities of didecyldimethylammonium chloride (DDAC) tended to be higher than those of polyhexamethylene biguanide (PHMB) and N-benzyl-N,N-dimethyldodecylammonium chloride (ADBAC). In particular, DDAC showed high bactericidal activity against approximately 90% of tested strains under the 5 h treatment.

  16. Bactericidal activity does not predict sterilizing activity: the case of rifapentine in the murine model of Mycobacterium ulcerans disease.

    Directory of Open Access Journals (Sweden)

    Deepak V Almeida

    Full Text Available Since 2004, treatment of Mycobacterium ulcerans disease, or Buruli ulcer, has shifted from surgery to daily treatment with streptomycin (STR + rifampin (RIF for 8 weeks. For shortening treatment duration, we tested the potential of daily rifapentine (RPT, a long-acting rifamycin derivative, as a substitute for RIF.BALB/c mice were infected with M. ulcerans in the right hind footpad and treated either daily (7/7 with STR+RIF or five days/week (5/7 with STR+RIF or STR+RPT for 4 weeks, beginning 28 days after infection when CFU counts were 4.88±0.51. The relative efficacy of the drug treatments was compared by footpad CFU counts during treatment and median time to footpad swelling after treatment cessation as measure of sterilizing activity. All drug treatments were bactericidal. After 1 week of treatment, the decline in CFU counts was significantly greater in treated mice but not different between the three treated groups. After 2 weeks of treatment, the decline in CFU was greater in mice treated with STR+RPT 5/7 than in mice treated with STR+RIF 7/7 and STR+RIF 5/7. After 3 and 4 weeks of treatment, CFU counts were nil in mice treated with STR+RPT and reduced by more than 3 and 4 logs in mice treated with STR+RIF 5/7 and STR+RIF 7/7, respectively. In sharp contrast to the bactericidal activity, the sterilizing activity was not different between all drug regimens although it was in proportion to the treatment duration.The better bactericidal activity of daily STR+RIF and especially of STR+RPT did not translate into better prevention of relapse, possibly because relapse-freecure after treatment of Buruli ulcer is more related to the reversal of mycolactone-induced local immunodeficiency by drug treatment rather than to the bactericidal potency of drugs.

  17. Bacilysin from Bacillus amyloliquefaciens FZB42 Has Specific Bactericidal Activity against Harmful Algal Bloom Species

    Science.gov (United States)

    Wu, Liming; Wu, Huijun; Chen, Lina; Xie, Shanshan; Zang, Haoyu; Borriss, Rainer

    2014-01-01

    Harmful algal blooms, caused by massive and exceptional overgrowth of microalgae and cyanobacteria, are a serious environmental problem worldwide. In the present study, we looked for Bacillus strains with sufficiently strong anticyanobacterial activity to be used as biocontrol agents. Among 24 strains, Bacillus amyloliquefaciens FZB42 showed the strongest bactericidal activity against Microcystis aeruginosa, with a kill rate of 98.78%. The synthesis of the anticyanobacterial substance did not depend on Sfp, an enzyme that catalyzes a necessary processing step in the nonribosomal synthesis of lipopeptides and polyketides, but was associated with the aro gene cluster that is involved in the synthesis of the sfp-independent antibiotic bacilysin. Disruption of bacB, the gene in the cluster responsible for synthesizing bacilysin, or supplementation with the antagonist N-acetylglucosamine abolished the inhibitory effect, but this was restored when bacilysin synthesis was complemented. Bacilysin caused apparent changes in the algal cell wall and cell organelle membranes, and this resulted in cell lysis. Meanwhile, there was downregulated expression of glmS, psbA1, mcyB, and ftsZ—genes involved in peptidoglycan synthesis, photosynthesis, microcystin synthesis, and cell division, respectively. In addition, bacilysin suppressed the growth of other harmful algal species. In summary, bacilysin produced by B. amyloliquefaciens FZB42 has anticyanobacterial activity and thus could be developed as a biocontrol agent to mitigate the effects of harmful algal blooms. PMID:25261512

  18. In vitro bactericidal and fungicidal activities of various extracts of saffron (Crocus sativus L. stigmas from Jammu & Kashmir, India

    Directory of Open Access Journals (Sweden)

    Syed Muzaffar

    2016-12-01

    Full Text Available Antimicrobial activities of methanolic and petroleum ether extracts of Croccus sativus L. (saffron stigmas, were tested against various bacterial strains (Proteus vulgaris, Klebsiella pneumonia, Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli and fungi (Candida albicans, Aspergillus niger and Aspergillus fumigatus by agar well diffusion method. Minimal inhibitory concentration and minimum bactericidal and fungicidal concentration values of each active extract were also determined. The results showed a strong activity of the petroleum ether and methanolic extracts of saffron stigmas against bacteria and fungi used as test organisms. The results of different antimicrobial assays also indicate that the extracts had significantly higher bactericidal than fungicidal activities (p < 0.05. The results suggest that these extracts can be used in pharmaceutical and food formulations for inhibiting pathogenic bacterial and fungal species.

  19. Biosynthesis and recovery of rod-shaped tellurium nanoparticles and their bactericidal activities

    Energy Technology Data Exchange (ETDEWEB)

    Zare, Bijan; Faramarzi, Mohammad Ali; Sepehrizadeh, Zargham [Department of Pharmaceutical Biotechnology and Biotechnology Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451 Tehran (Iran, Islamic Republic of); Shakibaie, Mojtaba [Department of Pharmacognosy and Biotechnology, School of Pharmacy, Pharmaceutics Research Center, Kerman University of Medical Sciences, P.O. Box 76175-493 Kerman (Iran, Islamic Republic of); Rezaie, Sassan [Department of Medical Biotechnology, School of Advanced Medical Technologies, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Shahverdi, Ahmad Reza, E-mail: shahverd@sina.tums.ac.ir [Department of Pharmaceutical Biotechnology and Biotechnology Research Center, Faculty of Pharmacy, Tehran University of Medical Sciences, P.O. Box 14155-6451 Tehran (Iran, Islamic Republic of)

    2012-11-15

    Highlights: ► Biosynthesis of rod shape tellurium nanoparticles with a hexagonal crystal structure. ► Extraction procedure for isolation of tellurium nanoparticles from Bacillus sp. BZ. ► Extracted tellurium nanoparticles have good bactericidal activity against some bacteria. -- Abstract: In this study, a tellurium-transforming Bacillus sp. BZ was isolated from the Caspian Sea in northern Iran. The isolate was identified by various tests and 16S rDNA analysis, and then used to prepare elemental tellurium nanoparticles. The isolate was subsequently used for the intracellular biosynthesis of elemental tellurium nanoparticles. The biogenic nanoparticles were released by liquid nitrogen and purified by an n-octyl alcohol water extraction system. The shape, size, and composition of the extracted nanoparticles were characterized. The transmission electron micrograph showed rod-shaped nanoparticles with dimensions of about 20 nm × 180 nm. The energy dispersive X-ray and X-ray diffraction spectra respectively demonstrated that the extracted nanoparticles consisted of only tellurium and have a hexagonal crystal structure. This is the first study to demonstrate a biological method for synthesizing rod-shaped elemental tellurium by a Bacillus sp., its extraction and its antibacterial activity against different clinical isolates.

  20. Bactericidal activity of organic extracts from Flourensia cernua DC against strains of Mycobacterium tuberculosis.

    Science.gov (United States)

    Molina-Salinas, Gloria María; Ramos-Guerra, Monica Celina; Vargas-Villarreal, Javier; Mata-Cárdenas, Benito David; Becerril-Montes, Pola; Said-Fernández, Salvador

    2006-01-01

    Tuberculosis is a chronic disease caused mainly by Mycobacterium tuberculosis. The emergence of antibiotic-resistant strains of this species underscores the need for novel effective drugs against resistant mycobacteria as first-line antituberculosis medications. Crude aqueous (obtained by decoction, in accordance with the traditional mode of preparation), methanol, acetone, and hexane extracts from aerial parts of Artemisia ludoviciana Nutt., Chenopodium ambrosioides L., Marrubium vulgare L., Mentha spicata L., and Flourensia cernua DC were assessed for their ability to either inhibit the growth of or kill M. tuberculosis strains H37Rv and CIBIN:UMF:15:99, the former being sensitive to, and the latter resistant to, streptomycin, isoniazide, rifampin, ethambutol, and pyrazinamide. These five plant species are used in Mexico to treat respiratory disorders. Flourensia cernua was the uniquely active plant among those evaluated. Its hexane and acetone extracts not only inhibited the growth of but killed M. tuberculosis. The hexane extract showed a minimal inhibitory concentration (MIC) of 50 and 25 microg/mL against sensitive and resistant strains, respectively; the acetone extract was active against only CIBIN:UMF:15:99 (MIC = 100 microg/mL). The hexane extract from F. cernua leaves could be an important source of bactericidal compounds against multidrug-resistant M. tuberculosis.

  1. Cathelicidin Antimicrobial Peptides with Reduced Activation of Toll-Like Receptor Signaling Have Potent Bactericidal Activity against Colistin-Resistant Bacteria

    Directory of Open Access Journals (Sweden)

    Cheng Kao

    2016-09-01

    Full Text Available The world is at the precipice of a postantibiotic era in which medical procedures and minor injuries can result in bacterial infections that are no longer effectively treated by antibiotics. Cathelicidins are peptides produced by animals to combat bacterial infections and to regulate innate immune responses. However, cathelicidins are potent activators of the inflammatory response. Cathelicidins with reduced proinflammatory activity and potent bactericidal activity in the low micromolar range against Gram-negative bacteria have been identified. Motifs in cathelicidins that impact bactericidal activity and cytotoxicity to human cells have been elucidated and used to generate peptides that have reduced activation of proinflammatory cytokine production and reduced cytotoxicity to human cells. The resultant peptides have bactericidal activities comparable to that of colistin and can kill colistin-resistant bacteria.

  2. Uric acid disrupts hypochlorous acid production and the bactericidal activity of HL-60 cells.

    Science.gov (United States)

    Carvalho, Larissa A C; Lopes, João P P B; Kaihami, Gilberto H; Silva, Railmara P; Bruni-Cardoso, Alexandre; Baldini, Regina L; Meotti, Flavia C

    2018-06-01

    Uric acid is the end product of purine metabolism in humans and is an alternative physiological substrate for myeloperoxidase. Oxidation of uric acid by this enzyme generates uric acid free radical and urate hydroperoxide, a strong oxidant and potentially bactericide agent. In this study, we investigated whether the oxidation of uric acid and production of urate hydroperoxide would affect the killing activity of HL-60 cells differentiated into neutrophil-like cells (dHL-60) against a highly virulent strain (PA14) of the opportunistic pathogen Pseudomonas aeruginosa. While bacterial cell counts decrease due to dHL-60 killing, incubation with uric acid inhibits this activity, also decreasing the release of the inflammatory cytokines interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF- α). In a myeloperoxidase/Cl - /H 2 O 2 cell-free system, uric acid inhibited the production of HOCl and bacterial killing. Fluorescence microscopy showed that uric acid also decreased the levels of HOCl produced by dHL-60 cells, while significantly increased superoxide production. Uric acid did not alter the overall oxidative status of dHL-60 cells as measured by the ratio of reduced (GSH) and oxidized (GSSG) glutathione. Our data show that uric acid impairs the killing activity of dHL-60 cells likely by competing with chloride by myeloperoxidase catalysis, decreasing HOCl production. Despite diminishing HOCl, uric acid probably stimulates the formation of other oxidants, maintaining the overall oxidative status of the cells. Altogether, our results demonstrated that HOCl is, indeed, the main relevant oxidant against bacteria and deviation of myeloperoxidase activity to produce other oxidants hampers dHL-60 killing activity. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  3. Antibodies with higher bactericidal activity induced by a Neisseria gonorrhoeae Rmp deletion mutant strain.

    Directory of Open Access Journals (Sweden)

    Guocai Li

    Full Text Available Neisseria gonorrhoeae (N. gonorrhoeae outer membrane protein reduction modifiable protein (Rmp has strong immunogenicity. However, anti-Rmp antibodies block rather than preserve the antibacterial effects of protective antibodies, which hampers the development of vaccines for gonococcal infections. We herein constructed an Rmp deletion mutant strain of N. gonorrhoeae by gene homologous recombination. The 261-460 nucleotide residues of Rmp gene amplified from N. gonorrhoeae WHO-A strain were replaced with a kanamycin-resistant Kan gene amplified from pET-28a. The resultant hybridized DNA was transformed into N. gonorrhoeae WHO-A strain. PCR was used to screen the colonies in which wild-type Rmp gene was replaced with a mutant gene fragment. Western blotting revealed that the Rmp deletion mutant strain did not express Rmp protein. Rmp deletion did not alter the morphological and Gram staining properties of the mutant strain that grew slightly more slowly than the wild-type one. Rmp gene mutated stably throughout 25 generations of passage. Antibody-mediated complement-dependent cytotoxicity assay indicated that the antibodies induced by the mutant strain had evidently higher bactericidal activities than those induced by the wild-type strain. Further modification of the Rmp deletion mutant strain is still required in the development of novel live attenuated vaccines for gonorrhea by Opa genes deletion or screening of phenotypic variant strains that do not express Opa proteins.

  4. Combined Roles of Human IgG Subclass, Alternative Complement Pathway Activation, and Epitope Density in the Bactericidal Activity of Antibodies to Meningococcal Factor H Binding Protein

    Science.gov (United States)

    Giuntini, Serena; Reason, Donald C.

    2012-01-01

    Meningococcal vaccines containing factor H binding protein (fHbp) are in clinical development. fHbp binds human fH, which enables the meningococcus to resist complement-mediated bacteriolysis. Previously, we found that chimeric human IgG1 mouse anti-fHbp monoclonal antibodies (MAbs) had human complement-mediated bactericidal activity only if the MAb inhibited fH binding. Since IgG subclasses differ in their ability to activate complement, we investigated the role of human IgG subclasses on antibody functional activity. We constructed chimeric MAbs in which three different murine fHbp-specific binding domains were each paired with human IgG1, IgG2, or IgG3. Against a wild-type group B isolate, all three IgG3 MAbs, irrespective of their ability to inhibit fH binding, had bactericidal activity that was >5-fold higher than the respective IgG1 MAbs, while the IgG2 MAbs had the least activity. Against a mutant with increased fHbp expression, the anti-fHbp MAbs elicited greater C4b deposition (classical pathway) and greater bactericidal activity than against the wild-type strain, and the IgG1 MAbs had similar or greater activity than the respective IgG3 MAbs. The bactericidal activity against both wild-type and mutant strains also was dependent, in part, on activation of the alternative complement pathway. Thus, at lower epitope density in the wild-type strain, the IgG3 anti-fHbp MAbs had the greatest bactericidal activity. At a higher epitope density in the mutant, the IgG1 MAbs had similar or greater bactericidal activity than the IgG3 MAbs, and the activity was less dependent on the inhibition of fH binding than at a lower epitope density. PMID:22064712

  5. Bactericidal activity of self-assembled palmitic and stearic fatty acid crystals on highly ordered pyrolytic graphite.

    Science.gov (United States)

    Ivanova, Elena P; Nguyen, Song Ha; Guo, Yachong; Baulin, Vladimir A; Webb, Hayden K; Truong, Vi Khanh; Wandiyanto, Jason V; Garvey, Christopher J; Mahon, Peter J; Mainwaring, David E; Crawford, Russell J

    2017-09-01

    The wings of insects such as cicadas and dragonflies have been found to possess nanostructure arrays that are assembled from fatty acids. These arrays can physically interact with the bacterial cell membranes, leading to the death of the cell. Such mechanobactericidal surfaces are of significant interest, as they can kill bacteria without the need for antibacterial chemicals. Here, we report on the bactericidal effect of two of the main lipid components of the insect wing epicuticle, palmitic (C16) and stearic (C18) fatty acids. Films of these fatty acids were re-crystallised on the surface of highly ordered pyrolytic graphite. It appeared that the presence of two additional CH 2 groups in the alkyl chain resulted in the formation of different surface structures. Scanning electron microscopy and atomic force microscopy showed that the palmitic acid microcrystallites were more asymmetric than those of the stearic acid, where the palmitic acid microcrystallites were observed to be an angular abutment in the scanning electron micrographs. The principal differences between the two types of long-chain saturated fatty acid crystallites were the larger density of peaks in the upper contact plane of the palmitic acid crystallites, as well as their greater proportion of asymmetrical shapes, in comparison to that of the stearic acid film. These two parameters might contribute to higher bactericidal activity on surfaces derived from palmitic acid. Both the palmitic and stearic acid crystallite surfaces displayed activity against Gram-negative, rod-shaped Pseudomonas aeruginosa and Gram-positive, spherical Staphylococcus aureus cells. These microcrystallite interfaces might be a useful tool in the fabrication of effective bactericidal nanocoatings. Nanostructured cicada and dragonfly wing surfaces have been discovered to be able physically kill bacterial cells. Here, we report on the successful fabrication of bactericidal three-dimensional structures of two main lipid

  6. Bactericidal active ingredient in cryopreserved plasma-treated water with the reduced-pH method for plasma disinfection

    Science.gov (United States)

    Kitano, Katsuhisa; Ikawa, Satoshi; Nakashima, Yoichi; Tani, Atsushi; Yokoyama, Takashi; Ohshima, Tomoko

    2016-09-01

    For the plasma disinfection of human body, plasma sterilization in liquid is crucial. We found that the plasma-treated water (PTW) has strong bactericidal activity under low pH condition. Physicochemical properties of PTW is discussed based on chemical kinetics. Lower temperature brings longer half-life and the bactericidal activity of PTW can be kept by cryopreservation. High performance PTW, corresponding to the disinfection power of 22 log reduction (B. subtilis spore), can be obtained by special plasma system equipped with cooling device. This is equivalent to 65% H2O2, 14% sodium hypochlorite and 0.33% peracetic acid, which are deadly poison for human. But, it is deactivated soon at higher temperature (4 sec. at body temperature), and toxicity to human body seems low. For dental application, PTW was effective on infected models of human extracted tooth. Although PTW has many chemical components, respective chemical components in PTW were isolated by ion chromatography. In addition to peaks of H2O2, NO2- and NO3-, a specific peak was detected. and only this fraction had bactericidal activity. Purified active ingredient of PTW is the precursor of HOO, and further details will be discussed in the presentation. MEXT (15H03583, 23340176, 25108505). NCCE (23-A-15).

  7. Synergistic bactericidal activity of chlorhexidine-loaded, silver-decorated mesoporous silica nanoparticles.

    Science.gov (United States)

    Lu, Meng-Meng; Wang, Qiu-Jing; Chang, Zhi-Min; Wang, Zheng; Zheng, Xiao; Shao, Dan; Dong, Wen-Fei; Zhou, Yan-Min

    2017-01-01

    Combination of chlorhexidine (CHX) and silver ions could engender synergistic bactericidal effect and improve the bactericidal efficacy. It is highly desired to develop an efficient carrier for the antiseptics codelivery targeting infection foci with acidic microenvironment. In this work, monodisperse mesoporous silica nanoparticle (MSN) nanospheres were successfully developed as an ideal carrier for CHX and nanosilver codelivery through a facile and environmentally friendly method. The CHX-loaded, silver-decorated mesoporous silica nanoparticles (Ag-MSNs@CHX) exhibited a pH-responsive release manner of CHX and silver ions simultaneously, leading to synergistically antibacterial effect against both gram-positive Staphylococcus aureus and gram-negative Escherichia coli . Moreover, the effective antibacterial concentration of Ag-MSNs@CHX showed less cytotoxicity on normal cells. Given their synergistically bactericidal ability and good biocompatibility, these nanoantiseptics might have effective and broad clinical applications for bacterial infections.

  8. Assessment of Bactericidal Drug Activity and Treatment Outcome in a Mouse Tuberculosis Model Using a Clinical Beijing Strain.

    Science.gov (United States)

    Mourik, Bas C; de Knegt, Gerjo J; Verbon, Annelies; Mouton, Johan W; Bax, Hannelore I; de Steenwinkel, Jurriaan E M

    2017-10-01

    Mycobacterium tuberculosis Beijing strains are associated with lower treatment success rates in tuberculosis (TB) patients. In contrast, laboratory strains such as H37Rv are often used in preclinical tuberculosis models. Therefore, we explored the impact of using a clinical Beijing strain on treatment outcome in our mouse tuberculosis model. Additionally, the predictive value of bactericidal activity on treatment outcome was assessed. BALB/c mice were infected with a Beijing strain and treated with one of 10 different combinations of conventional anti-TB drugs. Bactericidal activity was assessed by determining reductions in mycobacterial load after 7, 14, and 28 days and after 2, 3, and 6 months of treatment. Treatment outcome was evaluated after a 6-month treatment course and was based on lung culture status 3 months posttreatment. None of the anti-TB drug regimens tested could achieve 100% treatment success. Treatment outcome depended critically on rifampin. Four non-rifampin-containing regimens showed 0% treatment success compared to success rates between 81 and 95% for six rifampin-containing regimens. Bactericidal activity was predictive only for treatment outcome after 3 months of treatment. Our data advocate the use of multiple mycobacterial strains, including a Beijing strain, to increase the translational value of mouse TB models evaluating treatment outcome. Additionally, our findings support the notion that bactericidal activity in the first 2 months of treatment, as measured in clinical phase IIa/b trials, has limited predictive value for tuberculosis treatment outcome, thus emphasizing the need for better parameters to guide future phase IIII trials. Copyright © 2017 American Society for Microbiology.

  9. Influence of Rifampin Therapy on Serum Bactericidal Activity in the Presence of Cloxacillin and Vancomycin

    Directory of Open Access Journals (Sweden)

    Andrew MR Mackenzie

    1990-01-01

    Full Text Available In this study the effect of rifampin on serum inhibitory and serum bactericidal titres was examined. Sera were prepared from pooled human serum to contain vancomycin (10 mg/L, cloxacillin (5 mg/L or rifampin (1 mg/L, and the combinations cloxacillin/rifampin and vancomycin/rifampin. These five sera were tested by a microtitre method for serum inhibitory power and serum bactericidal titre against 11 strains of Staphylococcus aureus. A 48 h incubation period was required to detect full colony growth for subculture plates. It was found with all strains that the effect of the addition of rifampin to the other two antibiotics was to increase the serum inhibitory power, lower the serum bactericidal titre, increase the inhibitory/cidal ratio, and slow colony growth on subculture. In the clinical part of the study it was shown that only three of 38 sera (8% from patients receiving betalactam or vanomycin but not rifampin gave an inhibitory/cidal ratio greater than 8, but that nine of 10 sera (90% from patients receiving rifampin in addition to betalactam or vancomycin gave a ratio greater than 8 (P<0.001. The study verified that the effect of rifampin in serum was to increase inhibitory power and decrease bactericidal titre. The clinical significance of these results is not known and it is suggested that a high ratio of inhibitory to bactericidal titre in the presence of rifampin is to be expected, and that a low bactericidal titre under these circumstances is not necessarily an indication to modify therapy.

  10. Bactericidal activity of human lysozyme, muramidase-inactive lysozyme, and cationic polypeptides against Streptococcus sanguis and Streptococcus faecalis: inhibition by chitin oligosaccharides.

    OpenAIRE

    Laible, N J; Germaine, G R

    1985-01-01

    The basis of the bactericidal activity of human lysozyme against Streptococcus sanguis was studied. Experiments were designed to evaluate the role of lysozyme muramidase activity in its bactericidal potency. Inactivation of the muramidase activity of lysozyme was achieved by reduction of essential disulfides with dithiothreitol (DTT) or by incubation with the chitin oligosaccharides chitotriose and chitobiose. Muramidase-inactive lysozyme, prepared by reduction with DTT, was equal in bacteric...

  11. A comparative study of the bactericidal activity and daily disinfection housekeeping surfaces by a new portable pulsed UV radiation device.

    Science.gov (United States)

    Umezawa, Kazuo; Asai, Satomi; Inokuchi, Sadaki; Miyachi, Hayato

    2012-06-01

    Daily cleaning and disinfecting of non-critical surfaces in the patient-care areas are known to reduce the occurrence of health care-associated infections. However, the conventional means for decontamination of housekeeping surfaces of sites of frequent hand contact such as manual disinfection using ethanol wipes are laborious and time-consuming in daily practice. This study evaluated a newly developed portable pulsed ultraviolet (UV) radiation device for its bactericidal activity in comparison with continuous UV-C, and investigated its effect on the labor burden when implemented in a hospital ward. Pseudomonas aeruginosa, Multidrug-resistant P. aeruginosa, Escherichia coli, Acinetobacter baumannii, Amikacin and Ciprofloxacin-resistant A. baumannii, Staphylococcus aureus, Methicillin-resistant S. aureus and Bacillus cereus were irradiated with pulsed UV or continuous UV-C. Pulsed UV and continuous UV-C required 5 and 30 s of irradiation, respectively, to attain bactericidal activity with more than 2Log growth inhibition of all the species. The use of pulsed UV in daily disinfection of housekeeping surfaces reduced the working hours by half in comparison to manual disinfection using ethanol wipes. The new portable pulsed UV radiation device was proven to have a bactericidal activity against critical nosocomial bacteria, including antimicrobial-resistant bacteria after short irradiation, and was thus found to be practical as a method for disinfecting housekeeping surfaces and decreasing the labor burden.

  12. Development of a high-throughput method to evaluate serum bactericidal activity using bacterial ATP measurement as survival readout.

    Directory of Open Access Journals (Sweden)

    Francesca Necchi

    Full Text Available Serum Bactericidal Activity (SBA assay is the method of choice to evaluate the complement-mediated functional activity of both infection- and vaccine-induced antibodies. To perform a typical SBA assay, serial dilutions of sera are incubated with target bacterial strains and complement. The conventional SBA assay is based on plating on agar the SBA reaction mix and counting the surviving bacterial colony forming units (CFU at each serum dilution. Even with automated colony counting, it is labor-intensive, time-consuming and not amenable for large-scale studies. Here, we have developed a luminescence-based SBA (L-SBA method able to detect surviving bacteria by measuring their ATP. At the end of the SBA reaction, a single commercially available reagent is added to each well of the SBA plate, and the resulting luminescence signal is measured in a microplate reader. The signal obtained is proportional to the ATP present, which is directly proportional to the number of viable bacteria. Bactericidal activity is subsequently calculated. We demonstrated the applicability of L-SBA with multiple bacterial serovars, from 5 species: Citrobacter freundii, Salmonella enterica serovars Typhimurium and Enteritidis, Shigella flexneri serovars 2a and 3a, Shigella sonnei and Neisseria meningitidis. Serum bactericidal titers obtained by the luminescence readout method strongly correlate with the data obtained by the conventional agar plate-based assay, and the new assay is highly reproducible. L-SBA considerably shortens assay time, facilitates data acquisition and analysis and reduces the operator dependency, avoiding the plating and counting of CFUs. Our results demonstrate that L-SBA is a useful high-throughput bactericidal assay.

  13. Bactericidal activity under UV and visible light of cotton fabrics coated with anthraquinone-sensitized TiO2

    KAUST Repository

    Rahal, Raed

    2013-06-01

    This study describes a method derived from ISO/TC 206/SC specifications to assess the bactericidal activity against a bacterial strain, Pseudomonas fluorescens, of various photocatalytic fabrics, under UVA and filtered visible light. The experimental method allowed the accurate quantification of bacteria survival on photoactive surfaces and films under UVA and UV-free visible irradiation. Cotton fabrics coated with TiO2, anthraquinone or anthraquinone-sensitized TiO2 display a significant bactericidal efficiency. TiO2-coated fabrics are very efficient against P. fluorescens after 4 h UVA irradiation (bacteria survival below the detection limit). Under UVA-free visible light, anthraquinone-sensitized TiO2 coated fabrics induced a significant bactericidal activity after 2 h irradiation, while anthraquinone alone-coated fabrics were not as efficient and TiO2 coated fabrics were almost inefficient. These results show that although exhibiting a weak n-π* band in the 350-420 nm range, anthraquinone is a good candidate as an efficient visible light photosensitizer. A synergy effect between anthraquinone and TiO2 was demonstrated. A possible reaction mechanism, involving a synergy effect for singlet oxygen formation with anthraquinone-sensitized TiO2 is proposed to account for these results. © 2012 Elsevier B.V. All rights reserved.

  14. Neutralization of bactericidal activity related to antimicrobial carry-over in broiler carcass rinse samples

    Science.gov (United States)

    Chemical antimicrobial interventions used as poultry processing aids may have potential for carry-over into whole poultry carcass buffered peptone water (BPW) rinses collected for the recovery of viable Salmonella. Such carry-over may lead to false negative indications due to continuing bactericidal...

  15. Ability of Staphylococcus aureus coagulase genotypes to resist neutrophil bactericidal activity and phagocytosis

    DEFF Research Database (Denmark)

    Aarestrup, Frank Møller; Scott, N. L.; Sordillo, L. M.

    1994-01-01

    genotype. The interaction between bacteria and neutrophils was measured by phagocytosis and bactericidal effect. The average percent killing of bacteria was lowest (40.0%) with strains belonging to the most common genotype, medium (50%) with strains belonging to the intermediate type, and highest (64...

  16. Antagonistic effects of lipids against the bactericidal activity of thymol-beta-D-glucopyranoside

    Science.gov (United States)

    The gut of food-producing animals is a reservoir for zoonotic pathogens. Thymol is bactericidal against Salmonella, E. coli, and Campylobacter, but its rapid absorption from the proximal gut reveals a need for protective technologies to deliver effective concentrations to the lower gut where the pa...

  17. Cooperative Serum Bactericidal Activity Between Human Antibodies to Meningococcal Factor H Binding Protein and Neisserial Heparin Binding Antigen

    Science.gov (United States)

    Vu, David M.; Wong, Tracy T.; Granoff, Dan M.

    2011-01-01

    A meningococcal group B vaccine containing multiple protein antigens including factor H binding protein (fHbp) and Neisserial heparin binding antigen (NHba) is in clinical development. The ability of antibodies against individual antigens to interact and augment protective immunity is unknown. We assayed human complement-mediated bactericidal activity (SBA) in stored sera from six immunized adults before and after depletion of antibodies to fHbp and/or NHba. All six subjects developed ≥4-fold increases in SBA titer against a test strain with fHbp in the variant 1 group with an amino acid sequence that matched the vaccine antigen (GMT 95 percent of the SBA was directed against fHbp. Four subjects developed ≥4-fold increases in SBA titer against a test strain with a heterologous fHbp variant 2 antigen and a homologous NHba amino acid sequence that matched the vaccine antigen (GMT bactericidal anti-fHbp variant 1 antiserum with a mouse anti-NHba antiserum also augmented the anti-NHba SBA titer against this test strain. For meningococcal vaccines that target relatively sparsely-exposed antigens such fHbp or NHba, non-bactericidal antibodies against individual antigens can cooperate and elicit SBA. PMID:21241734

  18. Synthesis of silver nanoparticles by endosymbiont Pseudomonas fluorescens CA 417 and their bactericidal activity.

    Science.gov (United States)

    Syed, Baker; M N, Nagendra Prasad; B L, Dhananjaya; K, Mohan Kumar; S, Yallappa; S, Satish

    2016-12-01

    The present study emphasizes on biogenic synthesis of silver nanoparticles and their bactericidal activity against human and phytopathogens. Nanoparticle synthesis was performed using endosymbiont Pseudomonas fluorescens CA 417 inhabiting Coffea arabica L. Synthesized nanoparticles were characterized using hyphenated spectroscopic techniques such as UV-vis spectroscopy which revealed maximum absorption 425nm. Fourier transform infrared spectroscopy (FTIR) analysis revealed the possible functional groups mediating and stabilizing silver nanoparticles with predominant peaks occurring at 3346 corresponding to hydroxyl group, 1635 corresponding carbonyl group and 680 to aromatic group. X-ray diffraction (XRD) analysis revealed the Bragg's diffraction pattern with distinct peaks at 38° 44°, 64° and 78° revealing the face-centered cubic (fcc) metallic crystal corresponding to the (111), (200), (220) and (311) facets of the crystal planes at 2θ angle. The energy dispersive X-ray spectroscopy (EDS) analysis revealed presence of high intense absorption peak at 3keV is a typical characteristic of nano-crystalline silver which confirmed the presence of elemental silver. TEM analysis revealed the size of the nanoparticles to be in the range 5-50nm with polydisperse nature of synthesized nanoparticles bearing myriad shapes. The particle size determined by Dynamic light scattering (DLS) method revealed average size to be 20.66nm. The synthesized silver nanoparticles exhibited significant antibacterial activity against panel of test pathogens. The results showed Klebsiella pneumoniae (MTCC 7407) and Xanthomonas campestris to be more sensitive among the test human pathogen and phyto-pathogen respectively. The study also reports synergistic effect of silver nanoparticles in combination with kanamycin which displayed increased fold activity up to 58.3% against Klebsiella pneumoniae (MTCC 7407). The results of the present investigation are promising enough and attribute towards

  19. The Bactericidal Activity of the C-type Lectin RegIIIβ against Gram-negative Bacteria involves Binding to Lipid A*

    Science.gov (United States)

    Miki, Tsuyoshi; Holst, Otto; Hardt, Wolf-Dietrich

    2012-01-01

    RegIIIβ is a member of the C-type lectin family called RegIII. It is known to bind peptidoglycan, and its bactericidal activity shapes the interactions with commensal and pathogenic gut bacteria. However, little is known about its carbohydrate recognition specificity and the bactericidal mechanism, particularly against Gram-negative bacteria. Here, we show that RegIIIβ can bind directly to LPS by recognizing the carbohydrate moiety of lipid A via a novel motif that is indispensable for its bactericidal activity. This bactericidal activity of RegIIIβ could be inhibited by preincubation with LPS, lipid A, or gentiobiose. The latter is a disaccharide composed of two units of β-(1→6)-linked d-glucose and resembles the carbohydrate moiety of lipid A. Therefore, this structural element may form a key target site recognized by RegIIIβ. Using point-mutated RegIIIβ proteins, we found that amino acid residues in two structural motifs termed “loop 1” and “loop 2,” are important for peptidoglycan and lipid A binding (Arg-135, Asp-142) and for the bactericidal activity (Glu-134, Asn-136, Asp-142). Thus, the ERN motif and residue Asp-142 in the loop 2 are of critical importance for RegIIIβ function. This provides novel insights into the carbohydrate recognition specificity of RegIIIβ and explains its bactericidal activity against Gram-negative bacteria. PMID:22896700

  20. Algerian propolis extracts: Chemical composition, bactericidal activity and in vitro effects on gilthead seabream innate immune responses.

    Science.gov (United States)

    Soltani, El-Khamsa; Cerezuela, Rebeca; Charef, Noureddine; Mezaache-Aichour, Samia; Esteban, Maria Angeles; Zerroug, Mohamed Mihoub

    2017-03-01

    Propolis has been used as a medicinal agent for centuries. The chemical composition of four propolis samples collected from four locations of the Sétif region, Algeria, using gas chromatography-mass spectrometry was determined. More than 20 compounds and from 30 to 35 compounds were identified in the aqueous and ethanolic extracts, respectively. Furthermore, the antimicrobial activity of the propolis extracts against two marine pathogenic bacteria was evaluated. Finally, the in vitro effects of propolis on gilthead seabream (Sparus aurata L.) leucocyte activities were measured. The bactericidal activity of ethanolic extracts was very high against Shewanella putrefaciens, average against Photobacterium damselae and very low against Vibrio harveyi. The lowest bactericidal activity was always that found for the aqueous extracts. When the viability of gilthead seabream head-kidney leucocytes was measured after 30 min' incubation with the different extracts, both the ethanolic and aqueous extracts of one of the propolis samples (from Babor) and the aqueous extract of another (from Ain-Abbassa) provoked a significant decrease in cell viability when used at concentrations of 100 and 200 μg ml -1 . Furthermore, significant inhibitory effects were recorded on leucocyte respiratory burst activity when isolated leucocytes where preincubated with the extracts. This effect was dose-dependent in all cases except when extracts from a third propolis sample (from Boutaleb) were used. Our findings suggest that some of Algerian propolis extracts have bactericidal activity against important bacterial pathogens in seabream and significantly modulate in vitro leucocyte activities, confirming their potential as a source of new natural biocides and/or immunomodulators in aquaculture practice. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Broad-spectrum bactericidal activity of a new bioactive grafting material (F18) against clinically important bacterial strains.

    Science.gov (United States)

    Souza, M T; Campanini, L A; Chinaglia, C R; Peitl, O; Zanotto, E D; Souza, C W O

    2017-12-01

    Infection is the most relevant surgical complication in implant or grafting procedures. Osteomyelitis and other chronic conditions pose a constant challenge in current medical practice. In this context, a grafting biomaterial that possesses antibacterial properties combined with bioactivity could have great clinical impact. Researchers at the Vitreous Materials Laboratory (LaMaV-UFSCar) recently developed a glass composition, named F18, that presents an improved workability range combined with high bioactivity. With F18, one can easily manufacture complex shapes, such as scaffolds, continuous fibres and coat implants. This biomaterial has proven to be a viable alternative for bone and skin regeneration in in vivo tests, however its antimicrobial properties have not been explored. Hence, the purpose of this study was to systematically investigate the antibacterial activity of F18 in powder and fibre forms according to the JIS Z 2801:2010 standard. Whether incorporation of silver into F18 glass could impact its antimicrobial activity was also evaluated. Four clinically relevant Gram-positive and Gram-negative pathogenic bacterial strains (Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Pseudomonas aeruginosa) were used in this study. In both powder and fibre forms, F18 presented extremely efficient bactericidal activity against all strains tested, eliminating virtually 100% of the bacterial cells after 24 h. Kinetic tests showed that silver doping further increased the bactericidal activity, leading to S. aureus eradication in only 30 min after incubation. Both doped and non-doped glasses demonstrated very high bactericidal activity, making F18 a promising infection-preventing alternative for bone and wound regeneration in clinical practice. Copyright © 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

  2. Effect of adaptation process of Pseudomonas aeruginosa to didecyldimethylammonium chloride in 2-propanol on bactericidal efficiency of this active substance.

    Science.gov (United States)

    Chojecka, Agnieszka; Wiercińska, Olga; Röhm-Rodowald, Ewa; Kanclerski, Krzysztof; Jakimiak, Bożenna

    2014-01-01

    Microorganisms are characterized by two types of resistance innate and acquired. Innate resistance is associated with the construction of the surface structures. Wide use of active substances as antimicrobial compounds, especially in inhibitory concentrations, may promote the acquisition of bacterial resistance to these substances in the process of adaptation. The aim of the study was to determine changes in efficiency of didecyldimethylammonium chloride in 2-propanol (CMAP) against the Pseudomonas aeruginosa strains, which were adapted to this active substance. Adaptation studies were conducted using two strains: P. aeruginosa ATCC 15442 (PA), which is used in estimation of biocide efficiency and tetracycline-resistant P. aeruginosa ATCC 47085 (PAO-LAC) strain. These strains were adapted to the active substance Bardac22: 50% v/v didecyldimethylammonium chloride in 20% v/v 2-propanol (CMAP) according to the National Institute of Hygiene procedure. After adaptation, obtained isolates were classified to three groups and passaged to solid media: A - strains unadapted passaged onto slant medium without active substance, control group; B - strains with adaptive resistance passaged onto slant medium with 375 mg/l CMAP; C - strains with adaptive resistance passaged onto slant medium without CMAP. Changes in susceptibility of examined strains were determined on the basis of minimum inhibitory concentrations (MICs) by broth dilution method. The minimum bactericidal concentrations (MBCs) were determined by subculture P. aeruginosa strains on solid media without CMAP. The efficiency of CMAP against isolates obtained after adaptation processes was evaluated by using phenol coefficient (PC). There were no differences in the adaptation process between two strains of P. aeruginosa: PA and PAO-LAC. Both isolates obtained after the adaptation process was characterized by approximately 6-8 fold higher MICs compared to the MICs of these strains before the adaptation. Strains passaged

  3. Effect of food processing organic matter on photocatalytic bactericidal activity of titanium dioxide (TiO2).

    Science.gov (United States)

    Yemmireddy, Veerachandra K; Hung, Yen-Con

    2015-07-02

    The purpose of this study was to determine the effect of food processing organic matter on photocatalytic bactericidal activity of titanium dioxide (TiO2) nanoparticles (NPs). Produce and meat processing wash solutions were prepared using romaine lettuce and ground beef samples. Physico-chemical properties such as pH, turbidity, chemical oxygen demand (COD), total phenolics (for produce) and protein (for meat) content of the extracts were determined using standard procedures. The photocatalytic bactericidal activity of TiO2 (1 mg/mL) in suspension with or without organic matter against Escherichia coli O157:H7 (5-strain) was determined over a period of 3h. Increasing the concentration of organic matter (either produce or meat) from 0% to 100% resulted in 85% decrease in TiO2 microbicidal efficacy. 'Turbidity, total phenolics, and protein contents in wash solutions had significant effect on the log reduction. Increasing the total phenolics content in produce washes from 20 to 114 mg/L decreased the log reduction from 2.7 to 0.38 CFU/mL, whereas increasing the protein content in meat washes from 0.12 to 1.61 mg/L decreased the log reduction from and 5.74 to 0.87 CFU/mL. Also, a linear correlation was observed between COD and total phenolics as well as COD and protein contents. While classical disinfection kinetic models failed to predict, an empirical equation in the form of "Y=me(nX)" (where Y is log reduction, X is COD, and m and n are reaction rate constants) predicted the disinfection kinetics of TiO2 in the presence of organic matter (R(2)=94.4). This study successfully identified an empirical model with COD as a predictor variable to predict the bactericidal efficacy of TiO2 when used in food processing environment. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. An investigation of the bactericidal activity of selected essential oils to Aeromonas spp.

    Science.gov (United States)

    Starliper, Clifford E.; Ketola, H. George; Noyes, Andrew D.; Schill, William B.; Henson, Fred G.; Chalupnicki, Marc; Dittman, Dawn E.

    2015-01-01

    Diseases of fishes caused by Aeromonas spp. are common, have broad host ranges and may cause high mortality. Treatments of captive-reared populations using antimicrobials are limited with concerns for bacterial resistance development and environmental dissemination. This study was done to determine whether selected plant-derived essential oils were bactericidal to Aeromonas spp. Initially, twelve essential oils were evaluated using a disk diffusion assay to an isolate of A. salmonicida subsp. salmonicida, cause of fish furunculosis. The greatest zones of inhibition were obtained with oils of cinnamon Cinnamomum cassia, oregano Origanum vulgare, lemongrass Cymbopogon citratus and thyme Thymus vulgaris. Minimum bactericidal concentrations (MBC’s) were determined for these four oils, Allimed® (garlic extract, Allium sativum) and colloidal silver to sixty-nine isolates representing nine Aeromonas spp. The lowest mean MBCs (0.02–0.04%) were obtained with three different sources of cinnamon oil. MBCs for three sources of oregano and lemongrass oils ranged from 0.14% to 0.30% and 0.10% to 0.65%, respectively, and for two thyme oils were 2.11% and 2.22%. The highest concentration (5%) of Allimed® tested resulted in MBCs to twelve isolates. A concentration of silver greater than 15 mg/L would be required to determine MBCs for all but one isolate.

  5. Liposomes or traditional adjuvants: induction of bactericidal activity by the macrophage infectivity potentiator protein (Mip) of Neisseria meningitidis.

    Science.gov (United States)

    Costoya, Liliana; Marzoa, Juan; Ferreirós, Carlos; Criado, Maria Teresa

    2017-08-01

    Currently, one of the main approaches to achieve a vaccine for serogroup B Neisseria meningitidis is based on outer membrane proteins with low antigenic variability among strains. Since these proteins tend to be minor components of the outer membrane, recombinant production is required to obtain them in sufficient amounts for evaluation and development of vaccines. In this study, we analysed the ability of recombinant macrophage infectivity potentiator (rMip) protein to induce protective bactericidal activity in mice. The rMip protein was cloned from N. meningitidis strain H44/76 and was used to immunise mice, and the sera obtained were tested against the homologous and several heterologous N. meningitidis strains. The sera were obtained using the rMip alone, with adjuvant Al(OH) 3 , or after inclusion into liposomes. Bactericidal activity was variable depending on the strain, although high titres were seen against strains H44/76 and NmP27. Liposomes enhanced fourfold the reactivity against the homologous strain. The results presented suggest that the rMip protein should be considered a promising candidate for the improvement of future protein-based vaccines. © 2017 APMIS. Published by John Wiley & Sons Ltd.

  6. In Vitro Anaerobic Pharmacokinetic/Pharmacodynamic Model to Simulate the Bactericidal Activity of Levornidazole Against Bacteroides fragilis.

    Science.gov (United States)

    Hu, Jiali; Zhang, Jing; Chen, Yuancheng; Liang, Wang; Wu, Shi

    2017-04-01

    This study was designed to correlate the pharmacokinetic/pharmacodynamic (PK/PD) parameters with PD indices of levornidazole against Bacteroides fragilis and to calculate the PK/PD target value for levornidazole to attain its expected maximal bactericidal effect using an in vitro anaerobic dynamic PK/PD model. An anaerobic dynamic PK/PD model was developed in vitro. The scheme for PK modeling was designed according to the PK parameters of levornidazole in the human body. The device of 2-compartment PK/PD model was constructed by using digital control of flow rate to simulate 4 regimens of single-dose intravenous infusion of levornidazole to determine the bactericidal activity of levornidazole against the 3 strains of B fragilis within 72 hours. PD parameters such as reduction of colony count within 24 hours (∆Log 24h ), area under bactericidal curve (AUBC), and 2-hour initial killing rate (IKR) were calculated and correlated with PK/PD parameters. Sigmoid E max model of levornidazole was established to calculate PK/PD target values to attain corresponding PD effect. PK and PD validation proved the stability of the model in simulating levornidazole against B fragilis and the precision and accuracy in the results of PK modeling. C max and AUC 0-24h found only -1.46% and -6.72% differences from the values in vivo. Our study found that ∆Log 24h , AUBC, and IKR were more correlated with AUC 0-24h /MIC and C max /MIC than with %T>MIC. According to ∆Log 24h , the PK/PD target values of AUC 0-24h /MIC, C max /MIC, and %T>MIC of levornidazole against B fragilis were 157.6%, 14.1%, and 56.4%, respectively. Our findings are useful for optimizing the clinical dosing regimen of levornidazole sodium chloride injection to attain maximal bactericidal effect. Copyright © 2017 Elsevier HS Journals, Inc. All rights reserved.

  7. Role of antilipopolysaccharide antibodies in serum bactericidal activity against Salmonella enterica serovar Typhimurium in healthy adults and children in the United States.

    Science.gov (United States)

    Trebicka, Estela; Jacob, Susan; Pirzai, Waheed; Hurley, Bryan P; Cherayil, Bobby J

    2013-10-01

    Recent observations from Africa have rekindled interest in the role of serum bactericidal antibodies in protecting against systemic infection with Salmonella enterica serovar Typhimurium. To determine whether the findings are applicable to other populations, we analyzed serum samples collected from healthy individuals in the United States. We found that all but 1 of the 49 adult samples tested had robust bactericidal activity against S. Typhimurium in a standard in vitro assay. The activity was dependent on complement and could be reproduced by immunoglobulin G (IgG) purified from the sera. The bactericidal activity was inhibited by competition with soluble lipopolysaccharide (LPS) from S. Typhimurium but not from Escherichia coli, consistent with recognition of a determinant in the O-antigen polysaccharide. Sera from healthy children aged 10 to 48 months also had bactericidal activity, although it was significantly less than in the adults, correlating with lower levels of LPS-specific IgM and IgG. The lone sample in our collection that lacked bactericidal activity was able to inhibit killing of S. Typhimurium by the other sera. The inhibition correlated with the presence of an LPS-specific IgM and was associated with decreased complement deposition on the bacterial surface. Our results indicate that healthy individuals can have circulating antibodies to LPS that either mediate or inhibit killing of S. Typhimurium. The findings contrast with the observations from Africa, which linked bactericidal activity to antibodies against an S. Typhimurium outer membrane protein and correlated the presence of inhibitory anti-LPS antibodies with human immunodeficiency virus infection.

  8. The potent bactericidal activity of streptomycin in the guinea pig model of tuberculosis ceases due to the presence of persisters.

    Science.gov (United States)

    Ahmad, Zahoor; Pinn, Michael L; Nuermberger, Eric L; Peloquin, Charles A; Grosset, Jacques H; Karakousis, Petros C

    2010-10-01

    The biphasic kill curve of isoniazid against Mycobacterium tuberculosis in guinea pigs is due to the presence of persisters rather than selection of isoniazid-resistant mutants. To determine whether this phenomenon is common to other bactericidal drugs, we studied the activity of streptomycin and its ability to select for streptomycin-resistant mutants in the guinea pig model of tuberculosis. Pharmacokinetic studies were performed to establish the human-equivalent dose of streptomycin. Guinea pigs were aerosol-infected with M. tuberculosis and 2 weeks later streptomycin was given for 5 days/week via intramuscular injection. Bactericidal activity was assessed by homogenizing and plating lungs for cfu until 10 weeks of treatment. At each timepoint, cfu were isolated, suspended in normal saline and re-plated on plates containing 0.5, 1.0, 2.0 or 10.0 mg/L streptomycin. The human-equivalent dose of streptomycin was determined to be 70 mg/kg. Streptomycin showed potent activity during the first 14 days of treatment, rescuing all animals from acute tuberculosis-related death and reducing lung cfu by ∼4 log(10). However, streptomycin activity was dramatically reduced thereafter, as lung cfu declined by only ∼1 log(10) over the next 56 days of treatment. Although streptomycin-resistant mutants were detectable, their frequency of isolation was identical at treatment initiation and after 70 days of treatment. The reduced activity of streptomycin during the second phase of monotherapy is not associated with the selection of streptomycin-resistant mutants but, rather, with the presence of phenotypically tolerant 'persisters'.

  9. Preparation of AgBr@SiO{sub 2} core@shell hybrid nanoparticles and their bactericidal activity

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yuanyuan [Key Laboratory for Special Functional Materials of Ministry of Education, Henan University, Kaifeng 475004 (China); Yang, Lisu [Key Laboratory for Special Functional Materials of Ministry of Education, Henan University, Kaifeng 475004 (China); Henna Sports School, Zhengzhou 450045 (China); Zhao, Yanbao, E-mail: yanbaozhao@126.com [Key Laboratory for Special Functional Materials of Ministry of Education, Henan University, Kaifeng 475004 (China); Li, Binjie; Sun, Lei; Luo, Huajuan [Key Laboratory for Special Functional Materials of Ministry of Education, Henan University, Kaifeng 475004 (China)

    2013-04-01

    AgBr@SiO{sub 2} core@shell hybrid nanoparticles (NPs) were successfully prepared by sol-gel method. Their morphology and structure were characterized by transmission electron microscopy (TEM) and X-ray diffraction (XRD). The hybrid NPs are predominantly spherical in shape, with an average diameter of 180–200 nm, and each NP contains one inorganic core. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the hybrid NPs were examined against Staphylococcus aureus (S. aureus), Pseudomonas aeruginosa (P. aeruginosa) and Escherichia coli (E. coli), respectively. Results indicated that the AgBr@SiO{sub 2} NPs had excellent antibacterial activity. - Highlights: ► Presents a novel antibacterial agent “AgBr@ SiO{sub 2} NPs”. ► AgBr@SiO{sub 2} hybrid NPs could provide long-term antimicrobial effect. ► AgBr@SiO{sub 2} hybrid NPs have excellent antibacterial activity.

  10. Antimycobacterial agents differ with respect to their bacteriostatic versus bactericidal activities in relation to time of exposure, mycobacterial growth phase, and their use in combination.

    NARCIS (Netherlands)

    I.A.J.M. Bakker-Woudenberg (Irma); W. van Vianen (Wim); D. van Soolingen (Dick); H.A. Verbrugh (Henri); M.A. van Agtmael (Michiel)

    2005-01-01

    textabstractA number of antimycobacterial agents were evaluated with respect to their bacteriostatic activity (growth inhibition) versus the bactericidal activity against a clinical isolate of Mycobacterium avium (Mycobacterium avium complex [MAC] strain 101) in relation to the time of exposure and

  11. Binding of complement factor H to PorB3 and NspA enhances resistance of Neisseria meningitidis to anti-factor H binding protein bactericidal activity.

    Science.gov (United States)

    Giuntini, Serena; Pajon, Rolando; Ram, Sanjay; Granoff, Dan M

    2015-04-01

    Among 25 serogroup B Neisseria meningitidis clinical isolates, we identified four (16%) with high factor H binding protein (FHbp) expression that were resistant to complement-mediated bactericidal activity of sera from mice immunized with recombinant FHbp vaccines. Two of the four isolates had evidence of human FH-dependent complement downregulation independent of FHbp. Since alternative complement pathway recruitment is critical for anti-FHbp bactericidal activity, we hypothesized that in these two isolates binding of FH to ligands other than FHbp contributes to anti-FHbp bactericidal resistance. Knocking out NspA, a known meningococcal FH ligand, converted both resistant isolates to anti-FHbp susceptible isolates. The addition of a nonbactericidal anti-NspA monoclonal antibody to the bactericidal reaction also increased anti-FHbp bactericidal activity. To identify a role for FH ligands other than NspA or FHbp in resistance, we created double NspA/FHbp knockout mutants. Mutants from both resistant isolates bound 10-fold more recombinant human FH domains 6 and 7 fused to Fc than double knockout mutants prepared from two sensitive meningococcal isolates. In light of recent studies showing functional FH-PorB2 interactions, we hypothesized that PorB3 from the resistant isolates recruited FH. Allelic exchange of porB3 from a resistant isolate to a sensitive isolate increased resistance of the sensitive isolate to anti-FHbp bactericidal activity (and vice versa). Thus, some PorB3 variants functionally bind human FH, which in the presence of NspA enhances anti-FHbp resistance. Combining anti-NspA antibodies with anti-FHbp antibodies can overcome resistance. Meningococcal vaccines that target both NspA and FHbp are likely to confer greater protection than either antigen alone. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  12. Aging Enhances the Production of Reactive Oxygen Species and Bactericidal Activity in Peritoneal Macrophages by Upregulating Classical Activation Pathways

    Energy Technology Data Exchange (ETDEWEB)

    Smallwood, Heather S.; López-Ferrer, Daniel; Squier, Thomas C.

    2011-10-07

    Maintenance of macrophages in their basal state and their rapid activation in response to pathogen detection are central to the innate immune system, acting to limit nonspecific oxidative damage and promote pathogen killing following infection. To identify possible age-related alterations in macrophage function, we have assayed the function of peritoneal macrophages from young (3–4 months) and aged (14–15 months) Balb/c mice. In agreement with prior suggestions, we observe age-dependent increases in the extent of recruitment of macrophages into the peritoneum, as well as ex vivo functional changes involving enhanced nitric oxide production under resting conditions that contribute to a reduction in the time needed for full activation of senescent macrophages following exposure to lipopolysaccharides (LPS). Further, we observe enhanced bactericidal activity following Salmonella uptake by macrophages isolated from aged Balb/c mice in comparison with those isolated from young animals. Pathways responsible for observed phenotypic changes were interrogated using tandem mass spectrometry, which identified age-dependent increases in levels of proteins linked to immune cell pathways under basal conditions and following LPS activation. Immune pathways upregulated in macrophages isolated from aged mice include proteins critical to the formation of the immunoproteasome. Detection of these latter proteins is dramatically enhanced following LPS exposure for macrophages isolated from aged animals; in comparison, the identification of immunoproteasome subunits is insensitive to LPS exposure for macrophages isolated from young animals. Consistent with observed global changes in the proteome, quantitative proteomic measurements indicate that there are age-dependent abundance changes involving specific proteins linked to immune cell function under basal conditions. LPS exposure selectively increases the levels of many proteins involved in immune cell function in aged Balb/c mice

  13. In vitro bactericidal activity of Jinghua Weikang Capsule and its individual herb Chenopodium ambrosioides L. against antibiotic-resistant Helicobacter pylori.

    Science.gov (United States)

    Liu, Wei; Liu, Yu; Zhang, Xue-Zhi; Li, Ning; Cheng, Hong

    2013-01-01

    To investigate the bactericidal effects of Jinghua Weikang Capsule and its major component Chenopodium ambrosioides L. on antibiotic-resistant Helicobacter pylori. Four clinical antibiotic-resistant H. pylori strains were isolated and incubated in liquid medium containing Jinghua Weikang Capsule or Chenopodium ambrosioides L. By means of time-kill curve method, the average colony counts and bactericidal rate were calculated at time points of 0, 4, 8 and 24 h after the incubation and the time-kill curves were charted. Both Jinghua Weikang Capsule and Chenopodium ambrosioides L. at a concentration of 0.64 g/L showed obvious bactericidal effect against antibiotic-resistant H. pylori after 4 h of incubation. Jinghua Weikang Capsule and Chenopodium ambrosioides L. are considered to be active against antibiotic-resistant H. pylori in vitro.

  14. Bactericidal activity of green tea extracts: the importance of catechin containing nano particles.

    Science.gov (United States)

    Gopal, Judy; Muthu, Manikandan; Paul, Diby; Kim, Doo-Hwan; Chun, Sechul

    2016-01-28

    When we drink green tea infusion, we believe we are drinking the extract of the green tea leaves. While practically each tea bag infused in 300 mL water contains about 50 mg of suspended green tea leaf particles. What is the role of these particles in the green tea effect is the objective of this study. These particles (three different size ranges) were isolated via varying speed centrifugation and their respective inputs evaluated. Live oral bacterial samples from human volunteers have been screened against green tea extracts and macro, micro and nano sized green tea particles. The results showed that the presence/absence of the macro and mico sized tea particles in the green tea extract did not contribute much. However, the nano sized particles were characterized to be nature's nano stores of the bioactive catechins. Eradication of these nano tea particles resulted in decrease in the bactericidal property of the green tea extracts. This is a curtain raiser investigation, busting the nano as well as green tea leaf particle contribution in green tea extracts.

  15. Epithelial Cell Damage Activates Bactericidal/Permeability Increasing-Protein (BPI Expression in Intestinal Epithelium

    Directory of Open Access Journals (Sweden)

    Arjun Balakrishnan

    2017-08-01

    Full Text Available As the first line of defense against invading pathogen, intestinal epithelium produces various antimicrobial proteins (AMP that help in clearance of pathogen. Bactericidal/permeability-increasing protein (BPI is a 55 kDa AMP that is expressed in intestinal epithelium. Dysregulation of BPI in intestinal epithelium is associated with various inflammatory diseases like Crohn’s Disease, Ulcerative colitis, and Infectious enteritis’s. In this paper, we report a direct correlation between intestinal damage and BPI expression. In Caco-2 cells, we see a significant increase in BPI levels upon membrane damage mediated by S. aureus infection and pore-forming toxins (Streptolysin and Listeriolysin. Cells detect changes in potassium level as a Danger-associated molecular pattern associated with cell damage and induce BPI expression in a p38 dependent manner. These results are further supported by in vivo findings that the BPI expression in murine intestinal epithelium is induced upon infection with bacteria which cause intestinal damage (Salmonella Typhimurium and Shigella flexneri whereas mutants that do not cause intestinal damage (STM ΔfliC and STM ΔinvC did not induce BPI expression. Our results suggest that epithelial damage associated with infection act as a signal to induce BPI expression.

  16. [Antibacterial actin of vinegar against food-borne pathogenic bacteria including Escherichia coli O157:H7 (Part 2). Effect of sodium chloride and temperature on bactericidal activity].

    Science.gov (United States)

    Entani, E; Asai, M; Tsujihata, S; Tsukamoto, Y; Ohta, M

    1997-05-01

    Bactericidal effects of various kinds of AWASEZU (processed vinegar, 2.5% acidity) on food-borne pathogenic bacteria including Escherichia coli O157:H7 and other bacteria were examined. the order of bactericidal activities was NIHAIZU (3.5% NaCl was added) > SANBA-IZU (3.5% NaCl and 10% sucrose were added) > plain vinegar (spirit vinegar) > AMAZU (10% sucrose was added). This indicates that their activities were enhanced by the addition of sodium chloride and suppressed by the addition of sugar. On the other hand, when soy sauce was used instead of sodium chloride, the order of bactericidal activities was plain vinegar > AMAZU > NIHAIZU > SANBAIZU. This is mainly because their activities were suppressed by the increase in the pH value. The effect of sodium chloride (0.01-15%) and temperature (10-50 degrees C) on bactericidal activities against E. coli O157:H7 in spirit vinegar (0.5-2.5% acidity) was further examined. When vinegar was used in combination with sodium chloride, predominant synergism on the bactericidal activity was observed. Their activities were markedly enhanced by the addition of sodium chloride in proportion to the concentration. In addition to this, at higher temperatures spirit vinegar killed bacteria much more rapidly. It should be noted that the bactericidal activity of spirit vinegar was extremely enhanced by the combined use of the addition of sodium chloride and the rise of temperature. For example, in 2.5% acidity vinegar, the time required for 3 log decrease in viable cell numbers at 20 degrees C was shortened to 1/140-fold by the addition of 5% sodium chloride, shortened to 1/51-fold by the rise of the reaction temperature at 40 degrees C, and shortened to 1/830-fold; 0.89 minutes by both the addition of 5% sodium chloride and the rise of temperature at 40 degrees C. In order to propose the methods to prevent food poisoning by bacterial infection, bactericidal activities of vinegar solution containing sodium chloride on cooking tools and

  17. Colloidal titania-silica-iron oxide nanocomposites and the effect from silica thickness on the photocatalytic and bactericidal activities

    Energy Technology Data Exchange (ETDEWEB)

    Chanhom, Padtaraporn [Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330 (Thailand); Charoenlap, Nisanart [Laboratory of Biotechnology, Chulabhorn Research Institute, Bangkok 10210 (Thailand); Tomapatanaget, Boosayarat [Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330 (Thailand); Insin, Numpon, E-mail: Numpon.I@chula.ac.th [Department of Chemistry, Faculty of Science, Chulalongkorn University, Bangkok 10330 (Thailand)

    2017-04-01

    New types of colloidal multifunctional nanocomposites that combine superparamagnetic character and high photocatalytic activity were synthesized and investigated. The superparamagnetic nanocomposites composed of anatase titania, silica, and iron oxide nanoparticles (TSI) were synthesized using thermal decomposition method followed by microemulsion method, without calcination at high temperature. Different techniques including X-ray diffraction (XRD) and transmission electron microscope (TEM) were used to characterize and confirm the structure of the nanocomposites. These nanocomposites showed high photocatalytic activity when used in the photodegradation of methylene blue under irradiation with a black light lamp. Moreover, the nanocomposites exhibited high antibacterial properties. From our study, the nanocomposites can be useful in various applications such as removal of pollutants with readily separation from the environment using an external magnetic field. These composites could effectively photo-degrade the dye at least three cycles without regeneration. The effects of silica shell thickness on the photocatalytic activity was investigated, and the thickness of 6 nm of the silica interlayer is enough for the inhibition of electron translocation between titania and iron oxide nanoparticles and maintaining the efficiency of photocatalytic activity of titania nanoparticles. - Highlights: • New colloidal nanocomposites of iron oxide-silica-titania were prepared. • The nanocomposites exhibited high photocatalytic activity with magnetic response. • The effects of silica thickness on photocatalytic activity were investigated. • Bactericidal activity of the nanocomposites was demonstrated.

  18. Bactericidal activities of health-promoting,food-derived powders against the foodborne pathogens Escherichia coli,listeria monocytogenes, salmonella enterica,and staphylococcus aureus

    Science.gov (United States)

    We evaluated the relative bactericidal activities of 10 presumed health-promoting food-based powders (nutraceuticals) and for comparison, several selected known components of such powders against the following foodborne pathogens: Escherichia coli O157:H7, Salmonella enterica, Listeria monocytogenes...

  19. Synergistic interaction between wavelength of light and concentration of H₂O₂ in bactericidal activity of photolysis of H₂O₂.

    Science.gov (United States)

    Toki, Toshihide; Nakamura, Keisuke; Kurauchi, Michiko; Kanno, Taro; Katsuda, Yusuke; Ikai, Hiroyo; Hayashi, Eisei; Egusa, Hiroshi; Sasaki, Keiichi; Niwano, Yoshimi

    2015-03-01

    The present study aimed to evaluate the interaction between wavelength of light in the range of ultra violet A-visible and concentration of H2O2 in the reaction of photolysis of H2O2 from the point of view of hydroxyl radical (·OH) generation and the bactericidal activity. Light emitting diodes (LEDs) emitting the light at wavelengths of 365, 385, 400 and 465 nm were used at an irradiance of 1000 mW/cm(2). H2O2 was used at the final concentrations of 0, 250, 500, and 1000 mM. Quantitative analysis of ·OH generated by the LED irradiation of H2O2 were performed using an electron spin resonance-spin trapping technique. In a bactericidal assay, a bacterial suspension of Staphylococcus aureus prepared in sterile physiological saline was irradiated with the LEDs. The bactericidal activity of each test condition was evaluated by viable counts. When H2O2 was irradiated with the LEDs, ·OH was generated and bacteria were killed dependently on the concentration of H2O2 and the wavelength of LED. The two-way analysis of variance revealed that the wavelength, the H2O2 concentration and their interaction significantly affected the yield of ·OH and the bactericidal activity of the photolysis of H2O2. Therefore, it is suggested that bactericidal activity of photolysis of H2O2 could be enhanced by controlling the wavelength and the concentration of H2O2, which may contributes to shortening the treatment time and/or to reducing the concentration of H2O2. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  20. Bactericidal activity and mechanism of action of copper-sputtered flexible surfaces against multidrug-resistant pathogens.

    Science.gov (United States)

    Ballo, Myriam K S; Rtimi, Sami; Mancini, Stefano; Kiwi, John; Pulgarin, César; Entenza, José M; Bizzini, Alain

    2016-07-01

    Using direct current magnetron sputtering (DCMS), we generated flexible copper polyester surfaces (Cu-PES) and investigated their antimicrobial activity against a range of multidrug-resistant (MDR) pathogens including eight Gram-positive isolates (three methicillin-resistant Staphylococcus aureus [MRSA], four vancomycin-resistant enterococci, one methicillin-resistant Staphylococcus epidermidis) and four Gram-negative strains (one extended-spectrum β-lactamase-producing [ESBL] Escherichia coli, one ESBL Klebsiella pneumoniae, one imipenem-resistant Pseudomonas aeruginosa, and one ciprofloxacin-resistant Acinetobacter baumannii). Bactericidal activity (≥3 log10 CFU reduction of the starting inoculum) was reached within 15-30 min exposure to Cu-PES. Antimicrobial activity of Cu-PES persisted in the absence of oxygen and against both Gram-positive and Gram-negative bacteria containing elevated levels of catalases, indicating that reactive oxygen species (ROS) do not play a primary role in the killing process. The decrease in cell viability of MRSA ATCC 43300 and Enterococcus faecalis V583 correlated with the progressive loss of cytoplasmic membrane integrity both under aerobic and anaerobic conditions, suggesting that Cu-PES mediated killing is primarily induced by disruption of the cytoplasmic membrane function. Overall, we here present novel antimicrobial copper surfaces with improved stability and sustainability and provide further insights into their mechanism of killing.

  1. Propolis modulates miRNAs involved in TLR-4 pathway, NF-κB activation, cytokine production and in the bactericidal activity of human dendritic cells.

    Science.gov (United States)

    Conti, Bruno J; Santiago, Karina B; Cardoso, Eliza O; Freire, Paula P; Carvalho, Robson F; Golim, Marjorie A; Sforcin, José M

    2016-12-01

    Dendritic cells (DCs) are antigen-presenting cells, essential for recognition and presentation of pathogens to T cells. Propolis, a resinous material produced by bees from various plants, exhibits numerous biological properties, highlighting its immunomodulatory action. Here, we assayed the effects of propolis on the maturation and function of human DCs. DCs were generated from human monocytes and incubated with propolis and LPS. NF-κB and cytokines production were determined by ELISA. microRNA's expression was analysed by RT-qPCR and cell markers detection by flow cytometry. Colony-forming units were obtained to assess the bactericidal activity of propolis-treated DCs. Propolis activated DCs in the presence of LPS, inducing NF-kB, TNF-α, IL-6 and IL-10 production. The inhibition of hsa-miR-148a and hsa-miR-148b abolished the inhibitory effects on HLA-DR and pro-inflammatory cytokines. The increased expression of hsa-miR-155 may be correlated to the increase in TLR-4 and CD86 expression, maintaining LPS-induced expression of HLA-DR and CD40. Such parameters may be involved in the increased bactericidal activity of DCs against Streptococcus mutans. Propolis modulated the maturation and function of DCs and may be useful in the initial steps of the immune response, providing a novel approach to the development of DC-based strategies and for the discovery of new immunomodulators. © 2016 Royal Pharmaceutical Society.

  2. The Lytic SA Phage Demonstrate Bactericidal Activity against Mastitis Causing Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Hamza Ameer

    2016-01-01

    Full Text Available Staphylococcus aureus is the major causative agent of mastitis among dairy animals as it causes intramammary gland infection. Due to antibiotic resistance and contamination of antibiotics in the milk of diseased animals; alternative therapeutic agents are required to cure mastitis. Lytic bacteriophages and their gene products can be potential therapeutic agents against bacteria as they are host specific and less harmful than antibiotics. In this study, Staphylococcus aureus were isolated from milk samples of the infected animals and identified biochemically. SA phage was isolated from sewage water showing lytic activity against Staphylococcus aureus isolates. The highest lytic activity of bacteriophages was observed at 37°C and pH 7, and the most suitable storage condition was at 4°C. SA phage efficiently reduced bacterial growth in the bacterial reduction assay. The characterization and bacterial growth reduction activity of the bacteriophages against Staphylococcus aureus signifies their underlying potential of phage therapy against mastitis.

  3. Urine bactericidal activity against Escherichia coli isolates exhibiting different resistance phenotypes/genotypes in an in vitro pharmacodynamic model simulating urine concentrations obtained after oral administration of a 400-milligram single dose of cefditoren-pivoxil.

    Science.gov (United States)

    Sevillano, David; Aguilar, Lorenzo; Alou, Luis; Giménez, María-José; Torrico, Martha; González, Natalia; Cafini, Fabio; Relaño, María-Teresa; Coronel, Pilar; Prieto, José

    2008-03-01

    Activity of simulated cefditoren urinary concentrations was determined against seven Escherichia coli isolates. Bactericidal activity was obtained from 4 to 24 h against TEM-1 (penicillinase production/hyperproduction), TEM-34 (IRT-6), and TEM-116 (extended-spectrum beta-lactamase [ESBL]) and from 6 to 8 h against SHV/TEM-116 (ESBL) but never against SHV/TEM-1 (ESBL). Extension of bactericidal activity depended on the resistance genotype/phenotype tested.

  4. Bactericidal activity of alkaline salts of fatty acids towards bacteria associated with poultry processing

    Science.gov (United States)

    Antibacterial activity of alkaline salts of caproic, caprylic, capric, lauric, and myristic acids were determined using the agar diffusion assay. A 0.5M concentration of each fatty acid (FA) was dissolved in 1.0 M potassium hydroxide (KOH), and pH of the mixtures was adjusted to 10.5 with citric aci...

  5. Bactericidal activity of sera from adolescents vaccinated with bivalent rLP2086 against meningococcal serogroup B outbreak strains from France.

    Science.gov (United States)

    Taha, Muhamed-Kheir; Hawkins, Julio Cesar; Liberator, Paul; Deghmane, Ala-Eddine; Andrew, Lubomira; Hao, Li; Jones, Thomas R; McNeil, Lisa K; O'Neill, Robert E; Perez, John L; Jansen, Kathrin U; Anderson, Annaliesa S

    2017-03-13

    Bivalent rLP2086 (Trumenba®; MenB-FHbp), composed of two factor H binding proteins (FHbps), is a vaccine approved in the United States for prevention of Neisseria meningitidis serogroup B (MnB) invasive meningococcal disease (IMD). Bactericidal activity of sera from subjects vaccinated with bivalent rLP2086 was assessed against MnB isolates from recent disease outbreaks in France. MnB isolates from IMD cases were characterized by whole genome sequencing and FHbp expression was assessed using a flow cytometry-based assay. Sera from subjects (11-Bactericidal activity was measured in serum bactericidal assays using human complement (hSBAs). The response rate (RR) represents the percentage of subjects with an hSBA titer ⩾1:4. The six MnB outbreak isolates expressed diverse FHbp variants: A22, B03, B24 (two isolates), B44, and B228. FHbp expression levels ranged from 1309 to 8305 (mean fluorescence intensity units). The RR of preimmune sera from subjects was 7% to 27%. RRs increased for all isolates after each vaccine dose. After two doses, RRs ranged from 40% to 93%. After dose 3, RRs were ⩾73% for all isolates (range, 73%-100%). Each of the representative French outbreak isolates was killed by sera from subjects vaccinated with bivalent rLP2086. Vaccination elicited an immune response with bactericidal activity against these diverse isolates in a large proportion of subjects at risk. These results provide additional support for the licensure strategy of testing MnB strains expressing vaccine-heterologous FHbp variants in hSBAs and further illustrate the breadth of efficacy of this protein-based MnB vaccine. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Enteric pathogens deploy cell cycle inhibiting factors to block the bactericidal activity of Perforin-2

    OpenAIRE

    McCormack, Ryan M; Lyapichev, Kirill; Olsson, Melissa L; Podack, Eckhard R; Munson, George P

    2015-01-01

    eLife digest A wide range of bacteria and other microbes can infect animals and cause disease. Throughout evolution, these microbes and their hosts have been fighting never ending arms races in which the microbes deploy ever more elaborate weapons, while the hosts adapt to defend themselves. An animal's first line of defense is provided by its ?innate? immune system. This system is activated by the general features of microbial cells; for example, the molecules that make up the walls surround...

  7. Green synthesis of Silver and Gold Nanoparticles for Enhanced catalytic and bactericidal activity

    Science.gov (United States)

    Naraginti, S.; Tiwari, N.; Sivakumar, A.

    2017-11-01

    A rapid one step green synthetic method using kiwi fruit extract was employed for preparation of silver and gold nanoparticles. The synthesized nanoparticles were successfully used as green catalysts for the reduction of 4-nitrophenol (4-NP) and methylene blue (MB). They also exhibited excellent antimicrobial activity against clinically isolated Pseudomonas aeruginosa (P.aeruginosa) and Staphylococcus aureus (S.aureus). It was noticed that with increase in concentration of the aqueous silver and gold solutions, particle size of the Ag and Au NPS showed increase as evidenced from UV-Visible spectroscopy and TEM micrograph. The method employed for the synthesis required only a few minutes for more than 90% formation of nanoparticles when the temperature was raised to 80°C. It was also noticed that the catalytic activity of nanoparticles depends upon the size of the particles. These nanoparticles were observed to be crystalline from the clear lattice fringes in the transmission electron microscopic (TEM) images, bright circular spots in the selected area electron diffraction (SAED) pattern and peaks in the X-ray diffraction (XRD) pattern. The Fourier-transform infrared (FTIR) spectrum indicated the presence of different functional groups in the biomolecule capping the nanoparticles.

  8. Bactericidal activity of curcumin I is associated with damaging of bacterial membrane.

    Directory of Open Access Journals (Sweden)

    Poonam Tyagi

    Full Text Available Curcumin, an important constituent of turmeric, is known for various biological activities, primarily due to its antioxidant mechanism. The present study focused on the antibacterial activity of curcumin I, a significant component of commercial curcumin, against four genera of bacteria, including those that are Gram-positive (Staphylococcus aureus and Enterococcus faecalis and Gram-negative (Escherichia coli and Pseudomonas aeruginosa. These represent prominent human pathogens, particularly in hospital settings. Our study shows the strong antibacterial potential of curcumin I against all the tested bacteria from Gram-positive as well as Gram-negative groups. The integrity of the bacterial membrane was checked using two differential permeabilization indicating fluorescent probes, namely, propidium iodide and calcein. Both the membrane permeabilization assays confirmed membrane leakage in Gram-negative and Gram-positive bacteria on exposure to curcumin I. In addition, scanning electron microscopy and fluorescence microscopy were employed to confirm the membrane damages in bacterial cells on exposure to curcumin I. The present study confirms the broad-spectrum antibacterial nature of curcumin I, and its membrane damaging property. Findings from this study could provide impetus for further research on curcumin I regarding its antibiotic potential against rapidly emerging bacterial pathogens.

  9. Plant-mediated synthesis of biosilver nanoparticles using Pandanus amaryllifolius extract and its bactericidal activity

    Energy Technology Data Exchange (ETDEWEB)

    Akhir, Rabiatuladawiyah Md.; Fairuzi, Afiza Ahmad [School of Physics and Material Studies, Faculty of Applied Sciences, Universiti Teknologi MARA, Shah Alam, 40450 Selangor Darul Ehsan (Malaysia); Ismail, Nur Hilwani [School of Biology, Faculty of Applied Sciences, Universiti Teknologi MARA, Shah Alam, 40450 Selangor Darul Ehsan Malaysia (Malaysia)

    2015-08-28

    In this work, we describe a cost effective, easily scaled up and environmental friendly technique for green synthesis of silver nanoparticles (AgNPs) from 5 mM AgNO{sub 3} solution using aqueous extract of Pandanus amaryllifolius (P. amaryllifolius) leaves as reducing agent. Biosynthesized silver nanoparticles was confirmed by sampling the reaction mixture at regular intervals and the absorption maxima was scanned by Ultraviolet-Visible (UV-Vis) spectroscopy at wavelength of 200-500 nm. Images from Field Emission Scanning Electron Microscope (FESEM) have shown that the silver nanoparticles are 17-30 nm in range and assembled in mostly spherical shape. Elemental composition analysis by using Energy Dispersive X-ray (EDX) confirmed the presence of silver. Low concentration of biosynthesized silver nanoparticles have been found to exhibit good antibacterial activity against Staphylococcus aureus bacteria with average mean diameter of zone of inhibition (ZOI) of 16 mm.

  10. Periowave demonstrates bactericidal activity against periopathogens and leads to improved clinical outcomes in the treatment of adult periodontitis

    Science.gov (United States)

    Street, Cale N.; Andersen, Roger; Loebel, Nicolas G.

    2009-02-01

    Periodontitis affects half of the U.S. population over 50, and is the leading cause of tooth loss after 35. It is believed to be caused by growth of complex bacterial biofilms on the tooth surface below the gumline. Photodynamic therapy, a technology used commonly in antitumor applications, has more recently been shown to exhibit antimicrobial efficacy. We have demonstrated eradication of the periopathogens Porphyromonas gingivalis, Fusobacterium nucleatum, and Aggregatibacter actinomycetemcomitans in vitro using PeriowaveTM; a commercial photodisinfection system. In addition, several clinical studies have now demonstrated the efficacy of this treatment. A pilot study in the U.S. showed that 68% of patients treated with PeriowaveTM adjunctively to scaling and root planing (SRP) showed clinical attachment level increase of >1 mm, as opposed to 30% with SRP alone. In a subsequent larger study, a second PeriowaveTM treatment 6 weeks after initial treatment led to pocket depth improvements of >1.5 mm in 89% of patients. Finally, in the most recent multicenter, randomized, examiner-blinded study conducted on 121 subjects in Canada, PeriowaveTM treatment produced highly significant gains in attachment level (0.88 mm vs. 0.57 mm; p=0.003) and pocket depth (0.87 mm vs. 0.63 mm; p=0.01) as compared to SRP alone. In summary, PeriowaveTM demonstrated strong bactericidal activity against known periopathogens, and treatment of periodontitis using this system produced significantly better clinical outcomes than SRP alone. This, along with the absence of any adverse events in patients treated to date demonstrates that PDT is a safe and effective treatment for adult chronic periodontitis.

  11. In vitro bactericidal activity of blue light (465 nm) phototherapy on meticillin-susceptible and meticillin-resistant Staphylococcus pseudintermedius.

    Science.gov (United States)

    Schnedeker, Amy H; Cole, Lynette K; Lorch, Gwendolen; Diaz, Sandra F; Bonagura, John; Daniels, Joshua B

    2017-10-01

    Staphylococcus pseudintermedius is the most common cause of bacterial skin infections in dogs. Meticillin-resistant infections have become more common and are challenging to treat. Blue light phototherapy may be an option for treating these infections. The objective of this study was to measure the in vitro bactericidal activity of 465 nm blue light on meticillin-susceptible Staphylococcus pseudintermedius (MSSP) and meticillin-resistant Staphylococcus pseudintermedius (MRSP). We hypothesized that irradiation with blue light would kill MSSP and MRSP in a dose-dependent fashion in vitro as previously reported for meticillin-resistant Staphylococcus aureus (MRSA). In six replicate experiments, each strain [MSSP, n = 1; MRSP ST-71 (KM1381) n = 1; and MRSA (BAA-1680) n = 1] were cultivated on semisolid media, irradiated using a 465 nm blue light phototherapeutic device at the cumulative doses of 56.25, 112.5 and 225 J/cm 2 and incubated overnight at 35°C. Controls were not irradiated. Colony counts (CC) were performed manually. Descriptive statistics were performed and treatment effects assessed using the Wilcoxon-Mann-Whitney rank-sum test. Bonferroni-corrected rank-sum tests were performed for post hoc analysis when significant differences were identified. There was a significant decrease in CC with blue light irradiation at all doses for MRSA (P = 0.0006) but not for MSSP (P = 0.131) or MRSP (P = 0.589). Blue light phototherapy significantly reduced CC of MRSA, but not of MSSP or MRSP. The mechanism for the relative photosensitivity of the MRSA isolate is unknown, but is hypothesized to be due to an increased concentration of porphyrin in S. aureus relative to S. pseudintermedius, which would modulate blue light absorption. © 2017 ESVD and ACVD.

  12. Time Trends in Sputum Mycobacterial Load and Two-Day Bactericidal Activity of Isoniazid-Containing Antituberculosis Therapies

    Science.gov (United States)

    De Jager, Veronique; van der Merwe, Lize; Venter, Amour; Donald, Peter R.

    2017-01-01

    ABSTRACT Recent early bactericidal activity (EBA) studies of isoniazid-based antituberculosis therapies have shown a lower EBA over the first two treatment days than in earlier years. To quantify this trend and evaluate factors contributing to it, we extracted individual data from 18 studies with a total of 182 participants using isoniazid-containing therapies between 1992 and 2015 at a single site and laboratory in Cape Town, South Africa. We recalculated EBA as the daily fall in CFU per milliliter sputum up to day 2 of therapy (EBA0–2) for individual patients and treatment groups and used mixed-effects linear models to investigate the correlation between pretreatment CFU, EBA0–2, and year of study. We found that mean pretreatment CFU and year of study accounted for 46% and 47%, respectively, of the variation in mean EBA0–2. Mean pretreatment CFU differed between the periods 1992 to 2001 and 2007 to 2015 by 0.92 log10 CFU (95% confidence interval [CI], 0.57 to 1.28; P < 0.0001). On average, pretreatment CFU dropped by 0.053 log10 CFU (95% CI, 0.029 to 0.076; P = 0.0004) and EBA0–2 by 0.012 log10 CFU (95% CI, 0.006 to 0.018; P = 0.001) per year. The EBA0–2 of isoniazid-based antituberculosis therapy is strongly correlated with baseline mycobacterial load and shows a declining trend over the past 2 decades. PMID:28137798

  13. Cytotoxicity, Bactericidal, and Antioxidant Activity of Sodium Alginate Hydrosols Treated with Direct Electric Current.

    Science.gov (United States)

    Król, Żaneta; Marycz, Krzysztof; Kulig, Dominika; Marędziak, Monika; Jarmoluk, Andrzej

    2017-03-22

    The aim of the study was to investigate the effect of using direct electric current (DC) of 0, 200, and 400 mA for five minutes on the physiochemical properties, cytotoxicity, antibacterial, and antioxidant activity of sodium alginate hydrosols with different sodium chloride concentrations. The pH, oxidation-reduction potential (ORP), electrical conductivity (EC), and available chlorine concentration (ACC) were measured. The effect of sodium alginate hydrosols treated with DC on Staphylococcus aureus , Listeria monocytogenes , Bacillus cereus , Micrococcus luteus , Escherichia coli , Salmonella enteritidis , Yersinia enterocolitica , Pseudomonas fluorescence , and RAW 264.7 and L929 cells was investigated. Subsequently, the antioxidant properties of hydrosols were evaluated by determining the scavenging ability of 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH) and ferric reducing antioxidant power (FRAP). The results have shown that after applying 400 mA in hydrosol samples with 0.1% and 0.2% NaCl all tested bacteria were inactivated. The ACC concentration of C400 samples with NaCl was equal to 13.95 and 19.71 mg/L, respectively. The cytotoxicity analysis revealed that optimized electric field conditions and the addition of sodium chloride allow for the avoidance of toxicity effects on normal cells without disturbing the antibacterial effects. Due to the presence of oxidizing substances, the DPPH of variants treated with DC was lower than the DPPH of control samples.

  14. Cytotoxicity, Bactericidal, and Antioxidant Activity of Sodium Alginate Hydrosols Treated with Direct Electric Current

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    Żaneta Król

    2017-03-01

    Full Text Available The aim of the study was to investigate the effect of using direct electric current (DC of 0, 200, and 400 mA for five minutes on the physiochemical properties, cytotoxicity, antibacterial, and antioxidant activity of sodium alginate hydrosols with different sodium chloride concentrations. The pH, oxidation-reduction potential (ORP, electrical conductivity (EC, and available chlorine concentration (ACC were measured. The effect of sodium alginate hydrosols treated with DC on Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Micrococcus luteus, Escherichia coli, Salmonella enteritidis, Yersinia enterocolitica, Pseudomonas fluorescence, and RAW 264.7 and L929 cells was investigated. Subsequently, the antioxidant properties of hydrosols were evaluated by determining the scavenging ability of 1,1-diphenyl-2-picrylhydrazyl free radical (DPPH and ferric reducing antioxidant power (FRAP. The results have shown that after applying 400 mA in hydrosol samples with 0.1% and 0.2% NaCl all tested bacteria were inactivated. The ACC concentration of C400 samples with NaCl was equal to 13.95 and 19.71 mg/L, respectively. The cytotoxicity analysis revealed that optimized electric field conditions and the addition of sodium chloride allow for the avoidance of toxicity effects on normal cells without disturbing the antibacterial effects. Due to the presence of oxidizing substances, the DPPH of variants treated with DC was lower than the DPPH of control samples.

  15. Acorus calamus rhizome extract mediated biosynthesis of silver nanoparticles and their bactericidal activity against human pathogens

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    Chinnappan Sudhakar

    2015-12-01

    Full Text Available Silver nanoparticle (AgNP synthesis and characterization is an area of vast interest due to their broader application in the fields of science and technology and medicine. Plants are an attractive source for AgNP synthesis because of its ability to produce a wide range of secondary metabolites with strong reducing potentials. Thus, the present study describes the synthesis of AgNPs using aqueous rhizome extract of Acorus calamus (sweet flag. The AgNP formation was evaluated at different temperatures, incubation time and concentrations of AgNO3 using Response surface methodology based Box–Behnken design (BBD. The synthesized AgNPs were characterized by UV–Visible spectroscopy, Fourier transform infra-red spectroscopy (FTIR, X-ray diffraction (XRD, and Scanning electron microscopy–energy-dispersive spectroscopy (SEM–EDS. The surface plasmon resonance found at 420 nm confirmed the formation of AgNPs. SEM images reveal that the particles are spherical in nature. The EDS analysis of the AgNPs, using an energy range of 2–4 keV, confirmed the presence of elemental silver without any contamination. The antibacterial activity of synthesized AgNPs was evaluated against the clinical isolates Staphylococcus aureus and Escherichia coli and it was found that bacterial growth was significantly inhibited in a dose dependent manner. The results suggest that the AgNPs from rhizome extract could be used as a potential antibacterial agent for commercial application.

  16. Helicobacter pylori CagA triggers expression of the bactericidal lectin REG3γ via gastric STAT3 activation.

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    Kai Syin Lee

    Full Text Available BACKGROUND: Most of what is known about the Helicobacter pylori (H. pylori cytotoxin, CagA, pertains to a much-vaunted role as a determinant of gastric inflammation and cancer. Little attention has been devoted to potential roles of CagA in the majority of H. pylori infected individuals not showing oncogenic progression, particularly in relation to host tolerance. Regenerating islet-derived (REG3γ encodes a secreted C-type lectin that exerts direct bactericidal activity against Gram-positive bacteria in the intestine. Here, we extend this paradigm of lectin-mediated innate immunity, showing that REG3γ expression is triggered by CagA in the H. pylori-infected stomach. METHODOLOGY/PRINCIPAL FINDINGS: In human gastric mucosal tissues, REG3γ expression was significantly increased in CagA-positive, compared to CagA-negative H. pylori infected individuals. Using transfected CagA-inducible gastric MKN28 cells, we recapitulated REG3γ induction in vitro, also showing that tyrosine phosphorylated, not unphosphorylated CagA triggers REG3γ transcription. In concert with induced REG3γ, pro-inflammatory signalling downstream of the gp130 cytokine co-receptor via the signal transducer and activator of transcription (STAT3 and transcription of two cognate ligands, interleukin(IL-11 and IL-6, were significantly increased. Exogenous IL-11, but not IL-6, directly stimulated STAT3 activation and REG3γ transcription. STAT3 siRNA knockdown or IL-11 receptor blockade respectively abrogated or subdued CagA-dependent REG3γ mRNA induction, thus demonstrating a requirement for uncompromised signalling via the IL-11/STAT3 pathway. Inhibition of the gp130-related SHP2-(Ras-ERK pathway did not affect CagA-dependent REG3γ induction, but strengthened STAT3 activation as well as augmenting transcription of mucosal innate immune regulators, IL-6, IL-8 and interferon-response factor (IRF1. CONCLUSIONS/SIGNIFICANCE: Our results support a model of CagA-directed REG3

  17. Bactericidal activities of woven cotton and nonwoven polypropylene fabrics coated with hydroxyapatite-binding silver/titanium dioxide ceramic nanocomposite "Earth-plus"

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    Kasuga E

    2011-09-01

    Full Text Available Eriko Kasuga1,2, Yoshiyuki Kawakami2,3, Takehisa Matsumoto1, Eiko Hidaka1, Kozue Oana2, Naoko Ogiwara1, Dai Yamaki4, Tsukasa Sakurada4, Takayuki Honda1,51Department of Laboratory Medicine, Shinshu University Hospital, 2Division of Infection Control and Microbiological Regulation, Department of Health and Medical Sciences, Shinshu University Graduate School of Medicine, 3Division of Clinical Microbiology, Department of Biomedical Laboratory Sciences, School of Health Sciences, Shinshu University School of Medicine, 4Shinshu Ceramics Co Ltd, Kiso, Nagano, Japan; 5Department of Laboratory Medicine, Shinshu University School of Medicine, Matsumoto, JapanBackground: Bacteria from the hospital environment, including linens and curtains, are often responsible for hospital-associated infections. The aim of the present study was to evaluate the bactericidal effects of fabrics coated with the hydroxyapatite-binding silver/titanium dioxide ceramic nanocomposite "Earth-plus".Methods: Bactericidal activities of woven and nonwoven fabrics coated with Earth-plus were investigated by the time-kill curve method using nine bacterial strains, including three Staphylococcus aureus, three Escherichia coli, and three Pseudomonas aeruginosa strains.Results: The numbers of viable S. aureus and E. coli cells on both fabrics coated with Earth-plus decreased to below 2 log10 colony-forming units/mL in six hours and reached the detection limit in 18 hours. Viable cell counts of P. aeruginosa on both fabrics coated with Earth-plus could not be detected after 3–6 hours. Viable cells on woven fabrics showed a more rapid decline than those on nonwoven fabrics. Bacterial cell counts of the nine strains on fabrics without Earth-plus failed to decrease even after 18 hours.Conclusion: Woven cotton and nonwoven polypropylene fabrics were shown to have excellent antibacterial potential. The woven fabric was more bactericidal than the nonwoven fabric.Keywords: hydroxyapatite

  18. Bactericidal activities of woven cotton and nonwoven polypropylene fabrics coated with hydroxyapatite-binding silver/titanium dioxide ceramic nanocomposite "Earth-plus".

    Science.gov (United States)

    Kasuga, Eriko; Kawakami, Yoshiyuki; Matsumoto, Takehisa; Hidaka, Eiko; Oana, Kozue; Ogiwara, Naoko; Yamaki, Dai; Sakurada, Tsukasa; Honda, Takayuki

    2011-01-01

    Bacteria from the hospital environment, including linens and curtains, are often responsible for hospital-associated infections. The aim of the present study was to evaluate the bactericidal effects of fabrics coated with the hydroxyapatite-binding silver/titanium dioxide ceramic nanocomposite "Earth-plus". Bactericidal activities of woven and nonwoven fabrics coated with Earth-plus were investigated by the time-kill curve method using nine bacterial strains, including three Staphylococcus aureus, three Escherichia coli, and three Pseudomonas aeruginosa strains. The numbers of viable S. aureus and E. coli cells on both fabrics coated with Earth-plus decreased to below 2 log(10) colony-forming units/mL in six hours and reached the detection limit in 18 hours. Viable cell counts of P. aeruginosa on both fabrics coated with Earth-plus could not be detected after 3-6 hours. Viable cells on woven fabrics showed a more rapid decline than those on nonwoven fabrics. Bacterial cell counts of the nine strains on fabrics without Earth-plus failed to decrease even after 18 hours. Woven cotton and nonwoven polypropylene fabrics were shown to have excellent antibacterial potential. The woven fabric was more bactericidal than the nonwoven fabric.

  19. Bactericidal activities of woven cotton and nonwoven polypropylene fabrics coated with hydroxyapatite-binding silver/titanium dioxide ceramic nanocomposite “Earth-plus”

    Science.gov (United States)

    Kasuga, Eriko; Kawakami, Yoshiyuki; Matsumoto, Takehisa; Hidaka, Eiko; Oana, Kozue; Ogiwara, Naoko; Yamaki, Dai; Sakurada, Tsukasa; Honda, Takayuki

    2011-01-01

    Background Bacteria from the hospital environment, including linens and curtains, are often responsible for hospital-associated infections. The aim of the present study was to evaluate the bactericidal effects of fabrics coated with the hydroxyapatite-binding silver/titanium dioxide ceramic nanocomposite “Earth-plus”. Methods Bactericidal activities of woven and nonwoven fabrics coated with Earth-plus were investigated by the time-kill curve method using nine bacterial strains, including three Staphylococcus aureus, three Escherichia coli, and three Pseudomonas aeruginosa strains. Results The numbers of viable S. aureus and E. coli cells on both fabrics coated with Earth-plus decreased to below 2 log10 colony-forming units/mL in six hours and reached the detection limit in 18 hours. Viable cell counts of P. aeruginosa on both fabrics coated with Earth-plus could not be detected after 3–6 hours. Viable cells on woven fabrics showed a more rapid decline than those on nonwoven fabrics. Bacterial cell counts of the nine strains on fabrics without Earth-plus failed to decrease even after 18 hours. Conclusion Woven cotton and nonwoven polypropylene fabrics were shown to have excellent antibacterial potential. The woven fabric was more bactericidal than the nonwoven fabric. PMID:21931489

  20. Novel antiseptic compound OPB-2045G shows potent bactericidal activity against methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus both in vitro and in vivo: a pilot study in animals.

    Science.gov (United States)

    Inoue, Yasuhide; Hagi, Akifumi; Nii, Takuya; Tsubotani, Yoshie; Nakata, Hikaru; Iwata, Koushi

    2015-01-01

    There is a need for new compounds to effectively treat methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE). The novel monobiguanide compound 1-(3,4-dichlorobenzyl)-5-octylbiguanide gluconate (OPB-2045G) has potential bactericidal activity. We sought to elucidate the potency of OPB-2045G bactericidal activity against MRSA and VRE compared to those of chlorhexidine digluconate (CHG) and povidone iodine (PVP-I). In vitro bactericidal activity was analysed using minimum bactericidal concentration (MBC) as the index. The in vivo bactericidal efficacy of OPB-2045G was examined by determining MRSA and VRE contamination of the normal dorsal skin of mice following removal of hair. After a 3 min treatment period, the MBC of OPB-2045G was lower than that of CHG and PVP-I against standard strains and clinical isolates. Additionally, in our in vivo mouse model, the in vivo bactericidal activity of 1.5 % OPB-2045G (a clinically relevant dose) was higher than that of 0.5 % CHG and equivalent to that of 10 % PVP-I against MRSA. Similarly, the in vivo bactericidal activity of OPB-2045G was higher than that of 0.5 % CHG and 10 % PVP-I against VRE. OPB-2045G showed more potent bactericidal activity against MRSA and VRE both in vitro and in vivo compared to CHG and PVP-I, indicating that OPB-2045G may provide better protection against health care-associated infections caused by these pathogens. © 2015 The Authors.

  1. Mycobactericidal activity of sutezolid (PNU-100480 in sputum (EBA and blood (WBA of patients with pulmonary tuberculosis.

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    Robert S Wallis

    Full Text Available Sutezolid (PNU-100480 is a linezolid analog with superior bactericidal activity against Mycobacterium tuberculosis in the hollow fiber, whole blood and mouse models. Like linezolid, it is unaffected by mutations conferring resistance to standard TB drugs. This study of sutezolid is its first in tuberculosis patients.Sputum smear positive tuberculosis patients were randomly assigned to sutezolid 600 mg BID (N = 25 or 1200 mg QD (N = 25, or standard 4-drug therapy (N = 9 for the first 14 days of treatment. Effects on mycobacterial burden in sputum (early bactericidal activity or EBA were monitored as colony counts on agar and time to positivity in automated liquid culture. Bactericidal activity was also measured in ex vivo whole blood cultures (whole blood bactericidal activity or WBA inoculated with M. tuberculosis H37Rv.All patients completed assigned treatments and began subsequent standard TB treatment according to protocol. The 90% confidence intervals (CI for bactericidal activity in sputum over the 14 day interval excluded zero for all treatments and both monitoring methods, as did those for cumulative WBA. There were no treatment-related serious adverse events, premature discontinuations, or dose reductions due to laboratory abnormalities. There was no effect on the QT interval. Seven sutezolid-treated patients (14% had transient, asymptomatic ALT elevations to 173±34 U/L on day 14 that subsequently normalized promptly; none met Hy's criteria for serious liver injury.The mycobactericidal activity of sutezolid 600 mg BID or 1200 mg QD was readily detected in sputum and blood. Both schedules were generally safe and well tolerated. Further studies of sutezolid in tuberculosis treatment are warranted.ClinicalTrials.gov NCT01225640.

  2. Complement-Mediated Bactericidal Activity of Anti-Factor H Binding Protein Monoclonal Antibodies against the Meningococcus Relies upon Blocking Factor H Binding ▿

    Science.gov (United States)

    Giuntini, Serena; Reason, Donald C.; Granoff, Dan M.

    2011-01-01

    Binding of the complement-downregulating protein factor H (fH) to the surface of the meningococcus is important for survival of the organism in human serum. The meningococcal vaccine candidate factor H binding protein (fHbp) is an important ligand for human fH. While some fHbp-specific monoclonal antibodies (MAbs) block binding of fH to fHbp, the stoichiometry of blocking in the presence of high serum concentrations of fH and its effect on complement-mediated bactericidal activity are unknown. To investigate this question, we constructed chimeric antibodies in which the human IgG1 constant region was paired with three murine fHbp-specific binding domains designated JAR 3, JAR 5, and MAb502. By surface plasmon resonance, the association rates for binding of all three MAbs to immobilized fHbp were >50-fold higher than that for binding of fH to fHbp, and the MAb dissociation rates were >500-fold lower than that for fH. While all three MAbs elicited similar C1q-dependent C4b deposition on live bacteria (classical complement pathway), only those antibodies that inhibited binding of fH to fHbp (JAR 3 and JAR 5) had bactericidal activity with human complement. MAb502, which did not inhibit fH binding, had complement-mediated bactericidal activity only when tested with fH-depleted human complement. When an IgG1 anti-fHbp MAb binds to sparsely exposed fHbp on the bacterial surface, there appears to be insufficient complement activation for bacteriolysis unless fH binding also is inhibited. The ability of fHbp vaccines to elicit protective antibodies, therefore, is likely to be enhanced if the antibody repertoire is of high avidity and includes fH-blocking activity. PMID:21708990

  3. Synthesis, anti-inflammatory, bactericidal activities and docking studies of novel 1,2,3-triazoles derived from ibuprofen using click chemistry.

    Science.gov (United States)

    Angajala, Kishore Kumar; Vianala, Sunitha; Macha, Ramesh; Raghavender, M; Thupurani, Murali Krishna; Pathi, P J

    2016-01-01

    Nonsteroidal anti-inflammatory drugs are of vast therapeutic benefit in the treatment of different types of inflammatory conditions. 1,2,3-Triazoles and their derivatives have a wide range of applications as anti-bacterial, anti-fungal, anti-tubercular, cytostatic, anti-HIV, anti-allergic, anti-neoplastic and anti-inflammatory (AI) agents. Considering the individual biological and medicinal importance of ibuprofen and 1,2,3-triazoles, we wanted to explore novel chemical entities based on ibuprofen and triazole moieties towards their biological significance. Click chemistry has utilized as an ideal strategy to prepare novel ibuprofen-based 1,4-disubstituted 1,2,3-triazole containing molecules. These compounds were screened for their in vivo AI activity, among all the synthesized analogues 13o was shown potent effect than the reference AI drug ibuprofen at the same concentration (10 mg/kg body weight). Compounds 13l, 13g, 13c, 13k, 13i, 13n, 13m and 13j were shown significant AI activity. These triazole analogues were also screened for their bactericidal profile. Compounds 13c, 13i, 13l and 13o exhibited considerable bactericidal activity against gram positive and gram negative strains. In addition to this, molecular docking studies were also carried out into cyclooxygenase-2 active site to predict the affinity and orientation of these novel compounds (13a-q). In summary, we have designed and synthesized 1,2,3-triazole analogues of ibuprofen in good yields using Click chemistry approach. AI and bactericidal activities of these compounds were evaluated and shown remarkable results.

  4. Dietary Myrtle (Myrtus communis L.) improved non-specific immune parameters and bactericidal activity of skin mucus in rainbow trout (Oncorhynchus mykiss) fingerlings.

    Science.gov (United States)

    Mansouri Taee, Hadis; Hajimoradloo, Abdolmajid; Hoseinifar, Seyed Hossein; Ahmadvand, Hassan

    2017-05-01

    The present study examined the effects of dietary Myrtle (Myrtus communis L.) on non-specific immune parameters and bactericidal activity of skin mucus in rainbow trout (Oncorhynchus mykiss) fingerlings. Three hundred and sixty fingerlings (6.50 ± 0.55 g (were distributed in twelve cages (65 × 65 × 65 cm) with a metal framework. The study included four treatments repeated in triplicates. The treatments were feeding trouts with experimental diets containing different levels (0, 0.5, 1 and 1.5%) of Myrtle powder. The fingerlings were fed on experimental diet for sixty days and then skin mucus non-specific immune parameters as well as bactericidal activity were measured. At the end of the trial, the highest skin mucus soluble protein level was observed in group fed with 1.5% Myrtle (P alkaline phosphatase (ALP) activity was significantly increased in fish groups fed 1 and 1.5% Myrtle compared with the control group (P  0.05). Also, no antibacterial activity was detected against Escherichia coli, Staphylococcus aureus and Salmonella enterica in all treatments and control group. Whereas skin mucus of rainbow trout showed antimicrobial activity against fish pathogens (Aeromonas hydrophila and Yersinia ruckeri) in 1 and 1.5% Myrtle treatments. These results indicated beneficial effects of dietary Myrtle on mucosal immune parameters of fingerling rainbow trout. Copyright © 2017. Published by Elsevier Ltd.

  5. Susceptibility of Meningococcal Strains Responsible for Two Serogroup B Outbreaks on U.S. University Campuses to Serum Bactericidal Activity Elicited by the MenB-4C Vaccine.

    Science.gov (United States)

    Rossi, Raffaella; Beernink, Peter T; Giuntini, Serena; Granoff, Dan M

    2015-12-01

    In 2013 and 2014, two U.S. universities had meningococcal serogroup B outbreaks (a total of 14 cases) caused by strains from two different clonal complexes. To control the outbreaks, students were immunized with a serogroup B meningococcal vaccine (Novartis) that was not yet licensed in the United States. The vaccine (referred to as MenB-4C) contains four components capable of eliciting bactericidal activity. Both outbreak strains had high expression levels of two of the vaccine antigens (subfamily B factor H binding protein [FHbp] and neisserial heparin binding antigen [NHba]); the university B outbreak strain also had moderate expression of a third antigen, NadA. We investigated the bactericidal activity of sera from mice immunized with FHbp, NHba, or NadA and sera from MenB-4C-immunized infant macaques and an adult human. The postimmunization bactericidal activity of the macaque or human serum against isolates from university B with FHbp identification (ID) 1 that exactly matched the vaccine FHbp sequence variant was 8- to 21-fold higher than that against isolates from university A with FHbp ID 276 (96% identity to the vaccine antigen). Based on the bactericidal activity of mouse antisera to FHbp, NadA, or NHba and macaque or human postimmunization serum that had been depleted of anti-FHbp antibody, the bactericidal activity against both outbreak strains largely or entirely resulted from antibodies to FHbp. Thus, despite the high level of strain expression of FHbp from a subfamily that matched the vaccine antigen, there can be large differences in anti-FHbp bactericidal activity induced by MenB-4C vaccination. Further, strains with moderate to high NadA and/or NHba expression can be resistant to anti-NadA or anti-NHba bactericidal activity elicited by MenB-4C vaccination. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  6. Bactericidal catechins damage the lipid bilayer.

    Science.gov (United States)

    Ikigai, H; Nakae, T; Hara, Y; Shimamura, T

    1993-04-08

    The mode of antibacterial action of, the green tea (Camellia sinensis) extracts, (-)-epigallocatechin gallate (EGCg) and (-)-epicatechin (EC) was investigated. Strong bactericidal EGCg caused leakage of 5,6-carboxyfluorescein from phosphatidylcholine liposomes (PC), but EC with very weak bactericidal activity caused little damage to the membrane. Phosphatidylserine and dicetyl phosphate partially protected the membrane from EGCg-mediated damage when reconstituted into the liposome membrane with PC. EGCg, but not EC, caused strong aggregation and NPN-fluorescence quenching of PC-liposomes and these actions were markedly lowered in the presence of negatively charged lipids. These results show that bactericidal catechins primarily act on and damage bacterial membranes. The observation that Gram-negative bacteria are more resistant to bactericidal catechins than Gram-positive bacteria can be explained to some extent by the presence of negatively charged lipopolysaccharide.

  7. Bactericidal activity of the Ti-13Nb-13Zr alloy against different species of bacteria related with implant infection.

    Science.gov (United States)

    Aguilera-Correa, John-Jairo; Conde, Ana; Arenas, Maria-Angeles; de-Damborenea, Juan-Jose; Marin, Miguel; Doadrio, Antonio L; Esteban, Jaime

    2017-08-11

    The Ti-6Al-4V alloy is one of the most commonly used in orthopedic surgery. Despite its advantages, there is an increasing need to use new titanium alloys with no toxic elements and improved biomechanical properties, such as Ti-13Nb-13Zr. Prosthetic joint infections (PJI) are mainly caused by Gram-positive bacteria; however, Gram-negative bacteria are a growing problem due to associated multidrug resistance. In this study, the bacterial adherence and viability on the Ti-13Nb-13Zr alloy have been compared to that of the Ti-6Al-4V alloy using 16 collection and clinical strains of bacterial species related to PJI: Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa. When compared with the Ti-6Al-4V alloy, bacterial adherence on the Ti-13Nb-13Zr alloy was significantly higher in most staphylococcal and P. aeruginosa strains and lower for E. coli strains. The proportion of live bacteria was significantly lower for both Gram-negative species on the Ti-13Nb-13Zr alloy than on the Ti-6Al-4V alloy pointing to some bactericidal effect of the Ti-13Nb-13Zr alloy. This bactericidal effect appears to be a consequence of the formation of hydroxyl radicals, since this effect is neutralized when dimethylsulfoxide was added to both the saline solution and water used to wash the stain. The antibacterial effect of the Ti-13Nb-13Zr alloy against Gram-negative bacteria is an interesting property useful for the prevention of PJI caused by these bacteria on this potential alternative to the Ti-6Al-4V alloy for orthopedic surgery.

  8. Bactericidal Activity of Aqueous Acrylic Paint Dispersion for Wooden Substrates Based on TiO₂ Nanoparticles Activated by Fluorescent Light.

    Science.gov (United States)

    Zuccheri, Tommaso; Colonna, Martino; Stefanini, Ilaria; Santini, Cecilia; Gioia, Diana Di

    2013-08-02

    The photocatalytic effect of TiO 2 has great potential for the disinfection of surfaces. Most studies reported in the literature use UV activation of TiO₂, while visible light has been used only in a few applications. In these studies, high concentrations of TiO₂, which can compromise surface properties, have been used. In this work, we have developed an acrylic-water paint dispersion containing low TiO₂ content (2 vol %) for the inactivation of microorganisms involved in hospital-acquired infections. The nanoparticles and the coating have been characterized using spectroscopic techniques and transmission electron microscopy, showing their homogenous dispersion in the acrylic urethane coating. A common fluorescent light source was used to activate the photocatalytic activity of TiO₂. The paint dispersion showed antimicrobial activity against Escherichia coli , Staphylococcus aureus and Pseudomonas aeruginosa . The coating containing the TiO₂ nanoparticles maintained good UV stability, strong adhesion to the substrate and high hardness. Therefore, the approach used is feasible for paint formulation aimed at disinfection of healthcare surfaces.

  9. Colistin Increases the Cidal Activity of Antibiotic Combinations Against Multidrug-Resistant Klebsiella pneumoniae: An In Vitro Model Comparing Multiple Combination Bactericidal Testing at One Peak Serum Concentration and Time-Kill Method.

    Science.gov (United States)

    Mezzatesta, Maria Lina; Caio, Carla; Gona, Floriana; Zingali, Tiziana; Salerno, Iasmine; Stefani, Stefania

    2016-07-01

    The lack of treatment for multidrug-resistant (MDR) Enterobacteriaceae often leads to the use of double or triple antibiotic combinations to increase the option of clinical success. This study analyzes multiple combination bactericidal testing (MCBT) to screen double and triple antibiotic combinations, at standard peak serum concentration, for bactericidal activity against 21 MDR Klebsiella pneumoniae isolates. This method was compared with time-killing curves. The full bactericidal activity against all strains was obtained only by adding colistin. MCBT has a potential to become a rapid method for testing multiple antibiotic combinations for MDR microorganisms when colistin is used, providing clinicians with in vitro cidal data within 48 hr of strain isolation.

  10. Role of net charge on catalytic domain and influence of cell wall binding domain on bactericidal activity, specificity, and host range of phage lysins.

    Science.gov (United States)

    Low, Lieh Yoon; Yang, Chen; Perego, Marta; Osterman, Andrei; Liddington, Robert

    2011-09-30

    The recombinant lysins of lytic phages, when applied externally to Gram-positive bacteria, can be efficient bactericidal agents, typically retaining high specificity. Their development as novel antibacterial agents offers many potential advantages over conventional antibiotics. Protein engineering could exploit this potential further by generating novel lysins fit for distinct target populations and environments. However, access to the peptidoglycan layer is controlled by a variety of secondary cell wall polymers, chemical modifications, and (in some cases) S-layers and capsules. Classical lysins require a cell wall-binding domain (CBD) that targets the catalytic domain to the peptidoglycan layer via binding to a secondary cell wall polymer component. The cell walls of Gram-positive bacteria generally have a negative charge, and we noticed a correlation between (positive) charge on the catalytic domain and bacteriolytic activity in the absence of the CBD (nonclassical behavior). We investigated a physical basis for this correlation by comparing the structures and activities of pairs of lysins where the lytic activity of one of each pair was CBD-independent. We found that by engineering a reversal of sign of the net charge of the catalytic domain, we could either eliminate or create CBD dependence. We also provide evidence that the S-layer of Bacillus anthracis acts as a molecular sieve that is chiefly size-dependent, favoring catalytic domains over full-length lysins. Our work suggests a number of facile approaches for fine-tuning lysin activity, either to enhance or reduce specificity/host range and/or bactericidal potential, as required.

  11. Bactericidal application and cytotoxic activity of biosynthesized silver nanoparticles with an extract of the red seaweed Pterocladiella capillacea on the HepG2 cell line.

    Science.gov (United States)

    El Kassas, Hala Yassin; Attia, Azza Ahmed

    2014-01-01

    Nano-biotechnology is recognized as offering revolutionary changes in various fields of medicine. Biologically synthesized silver nanoparticles have a wide range of applications. Silver nanoparticles (AgNPs) were biosynthesized with an aqueous extract of Pterocladiella (Pterocladia) capillacea, used as a reducing and stabilizing agent, and characterized using UV-VIS spectroscopy, Fourier Transform Infra red (FT-IR) spectroscopy, transmission electron microscopy (TEM) and energy dispersive analysis (EDX). The biosynthesized AgNPs were tested for cytotoxic activity in a human hepatocellular carcinoma (HepG2) cell line cultured in Dulbecco's modified Eagle medium supplemented with 10% fetal bovine serum, 1% antibiotic and antimycotic solution and 2 mM glutamine. Bacterial susceptibility to AgNPs was assessed with Staphylococcus aureus, Bacillus subtilis [Gram+ve] and Pseudomonas aeruginosa and Escherichia coli [Gram-ve]. The agar well diffusion technique was adopted to evaluate the bactericidal activity of the biosynthesized AgNPs using Ampicillin and Gentamicin as gram+ve and gram-ve antibacterial standard drugs, respectively. The biosynthesized AgNPs were 11.4±3.52 nm in diameter. FT-IR analysis showed that carbonyl groups from the amino acid residues and proteins could assist in formation and stabilization of AgNPs. The AgNPs showed potent cytotoxic activity against the human hepatocellular carcinoma (HepG2) cell line at higher concentrations. The results also showed that the biosynthesized AgNPs inhibited the entire panel of tested bacteria with a marked specificity towards Bacillus subtillus. Cytotoxic activity of the biosynthesized AgNPs may be due to the presence of alkaloids present in the algal extract. Our AgNPs appear more bactericidal against gram-positive bacteria (B. subtillus).

  12. Functioned silver nanoparticle loaded activated carbon for the recovery of bioactive molecule from bacterial fermenter for its bactericidal activity

    Science.gov (United States)

    Arivizhivendhan, Villalan; Mahesh, Mannacharaju; Boopathy, Ramasamy; Karthikeyan, Sekar; Mary, Rathanasamy Regina; Sekaran, Ganesan

    2018-01-01

    A novel continuous production and extraction of bacterial bioactive prodigiosin (PG) from fermented using silver nanoparticle impregnated functioned activated carbon composite is proposed for cost-effective and ecofriendly microbial technique. Hence, in this investigation silver nanoparticle was impregnated onto functioned activated carbon ([AC]F) as a support matrix and to enable the separation of PG conjugated silver nanoparticle from the fermented medium. A laboratory scale experiment was carried out to evaluate the continuous production and recovery of PG using [AC@Ag]F. Ag nanoparticle impregnated [AC]F ([AC@Ag]F) characterized by FT-IR, XRD, TGA, DSC and SEM. Instrumental analyses confirmed that Ag nanoparticles significantly impregnated on AC through the functionalization of AC with diethanolamine and it enhances the binding capacity between AC and Ag. The various process parameters, such as contact time, pH, and mass of [AC@Ag]F, were statistically optimized for the recovery of PG using Response Surface Methodology (RSM). The maximum extraction of PG in [AC@Ag]F was found to be 16.2 ± 0.2 mg g-1, its twofold higher than [AC]F. Further, PG conjugated [AC@Ag]F and ([AC@Ag]F-PG) were checked for the growth inhibition of gram negative and gram positive bacteria without formation of biofilm upto 96 h. Hence, the developed matrix could be eco-friendly, viable and lower energy consumption step for separation of the bacterial bioactive PG from fermented broth. In additionally, [AC@Ag]F-PG was used as an antifouling matrix without formation of biofilm.

  13. Bactericidal Effect of Er:YAG Laser-Activated Sodium Hypochlorite Irrigation Against Biofilms of Enterococcus faecalis Isolate from Canal of Root-Filled Teeth with Periapical Lesions.

    Science.gov (United States)

    Cheng, Xiaogang; Xiang, Doudou; He, Wenxi; Qiu, Jun; Han, Bing; Yu, Qing; Tian, Yu

    2017-07-01

    This study was to evaluate the bactericidal effect of Er:YAG laser-activated sodium hypochlorite irrigation (Er:YAG + NaOCl) on biofilms of Enterococcus faecalis clinical isolate. It was reported that Er:YAG + NaOCl had effective bactericidal effect on laboratory-adapted E. faecalis strain, while no study has reported its effect on the clinical isolate. Eighteen E. faecalis strains were isolated from 39 root-filled teeth with periapical lesions, and their biofilm formation abilities were evaluated using the crystal violet staining method. Extracted human root canals were prepared to a 40#/.04 K3 instrument and contaminated with the E. faecalis isolate that presented the strongest biofilm formation ability for 4 weeks. The infected canals then received treatments of syringe irrigation with normal saline (NS) or NaOCl, ultrasonic activated irrigations US + NS and US + NaOCl, and Er:YAG laser-activated irrigations Er:YAG + NS and Er:YAG + NaOCl. The root canals were examined using scanning electron microscopy (SEM). The bacterial reductions were evaluated using the cell count method. SEM results showed that biofilm-like structures formed on the root canal walls after 4-week bacterial incubation. Er:YAG + NaOCl completely removed the E. faecalis biofilm from the root canal wall and made it the cleanest and most smooth surface among the treatment groups. Bacterial reductions in the treatment groups were presented in a descending order of Er:YAG + NaOCl (98.8%), US + NaOCl (98.6%) > NaOCl (94.0%) > Er:YAG + NS (91.9%) > US + NS (78.1%) > NS (51.1%) (p isolate, which may be considered an effective protocol for root canal treatment.

  14. Eco-friendly and green synthesis of silver nanoparticles using leaf extract of Strychnos potatorum Linn.F. and their bactericidal activities.

    Science.gov (United States)

    Kagithoju, Srikanth; Godishala, Vikram; Nanna, Rama Swamy

    2015-10-01

    Inspired green synthesis of metallic nanoparticles is evolving as an important branch of nanotechnology. Traditionally these are manufactured by wet chemical methods which require toxic and flammable chemicals. We report for the first time an economic and eco-friendly green synthesis of silver nanoparticles using Strychnos potatorum aqueous leaf extract from 3 mM silver nitrate solution. Nanoparticles thus formed are confirmed and characterized by using UV-Vis absorption spectroscopy, SEM and XRD measurements. The XRD and SEM analysis showed the average particle size of nanoparticles as 28 nm as well as revealed their (mixed, i.e., cubic and hexagonal) structure. Further, these green synthesized nanoparticles showed bactericidal activity against multidrug-resistant human pathogenic bacteria.

  15. Influence of the surface properties on bactericidal and fungicidal activity of magnetron sputtered Ti–Ag and Nb–Ag thin films

    Energy Technology Data Exchange (ETDEWEB)

    Wojcieszak, D., E-mail: damian.wojcieszak@pwr.edu.pl [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wrocław (Poland); Mazur, M.; Kaczmarek, D. [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wrocław (Poland); Mazur, P. [Institute of Experimental Physics, University of Wrocław, Max Born 9, 50-204 Wrocław (Poland); Szponar, B. [Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Rudolfa Weigla 12, 53–114 Wrocław (Poland); Domaradzki, J. [Faculty of Microsystem Electronics and Photonics, Wroclaw University of Technology, Janiszewskiego 11/17, 50-372 Wrocław (Poland); Kepinski, L. [Institute of Low Temperature and Structure Research, Polish Academy of Sciences, Okólna 2, 50-422 Wrocław (Poland)

    2016-05-01

    In this study the comparative investigations of structural, surface and bactericidal properties of Ti–Ag and Nb–Ag thin films have been carried out. Ti–Ag and Nb–Ag coatings were deposited on silicon and fused silica substrates by magnetron co-sputtering method using innovative multi-target apparatus. The physicochemical properties of prepared thin films were examined with the aid of X-ray diffraction, grazing incidence X-ray diffraction, scanning electron microscopy, atomic force microscopy and X-ray photoelectron spectroscopy methods. Moreover, the wettability of the surface was determined. It was found that both, Ti–Ag and Nb–Ag thin films were nanocrystalline. In the case of Ag–Ti film presence of AgTi{sub 3} and Ag phases was identified, while in the structure of Nb–Ag only silver occurred in a crystal form. In both cases the average size of crystallites was ca. 11 nm. Moreover, according to scanning electron microscopy and atomic force microscopy investigations the surface of Nb–Ag thin films was covered with Ag-agglomerates, while Ti–Ag surface was smooth and devoid of silver particles. Studies of biological activity of deposited coatings in contact with Bacillus subtilis, Pseudomonas aeruginosa, Enterococcus hirae, Klebisiella pneumoniae, Escherichia coli, Staphylococcus aureus and Candida albicans were performed. It was found that prepared coatings were bactericidal and fungicidal even in a short term-contact, i.e. after 2 h. - Highlights: • Surface and biological properties of Ti–Ag and Nb–Ag thin films were examined. • Ag content was related to sputtering yields and nucleation of Ti and Nb. • For Nb–Ag film the agglomeration of silver at the surface was observed. • Composition and surface topography had an impact on antimicrobial properties. • Fine-grained surface was important in Ag ions release process.

  16. Aqueous and Organic Solvent-Extracts of Selected South African Medicinal Plants Possess Antimicrobial Activity against Drug-Resistant Strains of Helicobacter pylori: Inhibitory and Bactericidal Potential

    Directory of Open Access Journals (Sweden)

    Collise Njume

    2011-09-01

    Full Text Available The aim of this study was to identify sources of cheap starting materials for the synthesis of new drugs against Helicobacter pylori. Solvent-extracts of selected medicinal plants; Combretum molle, Sclerocarya birrea, Garcinia kola, Alepidea amatymbica and a single Strychnos species were investigated against 30 clinical strains of H. pylori alongside a reference control strain (NCTC 11638 using standard microbiological techniques. Metronidazole and amoxicillin were included in these experiments as positive control antibiotics. All the plants demonstrated anti-H. pylori activity with zone diameters of inhibition between 0 and 38 mm and 50% minimum inhibitory concentration (MIC50 values ranging from 0.06 to 5.0 mg/mL. MIC50 values for amoxicillin and metronidazole ranged from 0.001 to 0.63 mg/mL and 0.004 to 5.0 mg/mL respectively. The acetone extracts of C. molle and S. birrea exhibited a remarkable bactericidal activity against H. pylori killing more than 50% of the strains within 18 h at 4× MIC and complete elimination of the organisms within 24 h. Their antimicrobial activity was comparable to the control antibiotics. However, the activity of the ethanol extract of G. kola was lower than amoxicillin (P < 0.05 as opposed to metronidazole (P > 0.05. These results demonstrate that S. birrea, C. molle and G. kola may represent good sources of compounds with anti-H. pylori activity.

  17. Ceftaroline plus Avibactam Demonstrates Bactericidal Activity against Pathogenic Anaerobic Bacteria in a One-Compartment In Vitro Pharmacokinetic/Pharmacodynamic Model

    Science.gov (United States)

    Werth, Brian J.

    2014-01-01

    Anaerobic pathogens are often associated with polymicrobial infections, such as diabetic foot infections. Patients with these infections are often treated with broad-spectrum, multidrug therapies targeting resistant Gram-positive bacteria, such as methicillin-resistant Staphylococcus aureus, as well as Gram-negative bacteria and anaerobes. The broad-spectrum, non-beta-lactam, beta-lactamase inhibitor avibactam has been combined with ceftaroline and may provide a single-product alternative for complicated polymicrobial infections. We compared the activity of ceftaroline-avibactam (CPA) to that of ertapenem (ERT) against common anaerobic pathogens in an in vitro pharmacokinetic/pharmacodynamic (PK/PD) model. Simulations of doses of ceftaroline-fosamil at 600 mg every 8 h (q8h) (maximum free drug concentration [fCmax], 17.04 mg/liter, and half-life [t1/2], 2.66 h) plus avibactam at 600 mg q8h (fCmax, 11.72 mg/liter, and t1/2, 1.8 h) and of ertapenem at 1 g q24h (fCmax, 13 mg/liter, and t1/2, 4 h) were evaluated against two strains of Bacteroides fragilis, one strain of Prevotella bivia, and one strain of Finegoldia magna in an anaerobic one-compartment in vitro PK/PD model over 72 h with a starting inoculum of ∼8 log10 CFU/ml. Bactericidal activity was defined as a reduction of ≥3 log10 CFU/ml from the starting inoculum. Both CPA and ERT were bactericidal against all four strains. CPA demonstrated improved activity against Bacteroides strains compared to that of ERT but had similar activity against Finegoldia magna and P. bivia, although modest regrowth was observed with CPA against P. bivia. No resistance emerged from any of the models. The pharmacokinetics achieved were 92 to 105% of the targets. CPA has potent in vitro activity against common anaerobic pathogens at clinically relevant drug exposures and may be a suitable single product for the management of complicated polymicrobial infections. PMID:24217692

  18. A combination of ceftaroline and daptomycin has synergistic and bactericidal activity in vitro against daptomycin nonsusceptible methicillin-resistant Staphylococcus aureus (MRSA).

    Science.gov (United States)

    Shafiq, Iffat; Bulman, Zackery P; Spitznogle, Sarah L; Osorio, Justin E; Reilly, Irene S; Lesse, Alan J; Parameswaran, Ganapathi I; Mergenhagen, Kari A; Tsuji, Brian T

    2017-05-01

    There is an urgent need to optimize therapeutic options in patients with methicillin-resistant Staphylococcus aureus (MRSA) bacteremia who have failed conventional therapy. Two clinical isolates were obtained from a 68-year-old male with persistent MRSA bacteremia before and after the development of daptomycin nonsusceptibility. The pharmacodynamic activity of monotherapies and combinations of ceftaroline, daptomycin, cefoxitin, nafcillin and vancomycin were evaluated in time-kill experiments versus 10 8 CFU/mL of the pre- and post-daptomycin nonsusceptible MRSA isolates. Cefoxitin, nafcillin and vancomycin alone or in combination with ceftaroline failed to generate prolonged bactericidal activity against the post-daptomycin nonsusceptible isolate whereas a ceftaroline-daptomycin combination resulted in 6, 24 and 48 h log 10 (CFU/mL) reductions of 3.90, 4.40 and 6.32. Population analysis profiles revealed a daptomycin heteroresistant subpopulation of the pre-daptomycin nonsusceptible MRSA isolate that expanded by >10,000× on daptomycin agar containing 2-16 mg/L in the post-daptomycin nonsusceptible isolate. Daptomycin and ceftaroline combinations may be promising against persistent MRSA bacteremia.

  19. Exploring a new phenomenon in the bactericidal response of TiO{sub 2} thin films by Fe doping: Exerting the antimicrobial activity even after stoppage of illumination

    Energy Technology Data Exchange (ETDEWEB)

    Naghibi, Sanaz, E-mail: naghibi@iaush.ac.ir [Department of Metallurgy and Materials Engineering, Shahreza Branch, Islamic Azad University, Isfahan (Iran, Islamic Republic of); Vahed, Shohreh, E-mail: sh_vahed@iaush.ac.ir [Department of Food Science, Shahreza Branch, Islamic Azad University, Isfahan (Iran, Islamic Republic of); Torabi, Omid, E-mail: omid_trb@yahoo.com [Department of Materials Engineering, Najafabad Branch, Advanced Materials Research Center, Islamic Azad University, Isfahan (Iran, Islamic Republic of); Jamshidi, Amin, E-mail: amin_jam_g@yahoo.com [Department of Materials Engineering, Najafabad Branch, Advanced Materials Research Center, Islamic Azad University, Isfahan (Iran, Islamic Republic of); Golabgir, Mohammad Hossein, E-mail: m.hosseingolabgir@yahoo.com [Department of Materials Engineering, Najafabad Branch, Advanced Materials Research Center, Islamic Azad University, Isfahan (Iran, Islamic Republic of)

    2015-02-01

    Graphical abstract: - Highlights: • Highly uniform Fe–TiO{sub 2} thin films were deposited on glass using sol–gel hot-dipping technique. • The photocatalytic properties were studied upon UV and visible irradiation. • By Fe doping into TiO{sub 2} structure, its microbial performance was prolonged even after stopping the illumination. • Due to Fe doping, the significant improvement in bactericidal coating was evident. - Abstract: Antibacterial properties of Fe-doped TiO{sub 2} thin films prepared on glass by the sol–gel hot-dipping technique were studied. The films were characterized by X-ray diffraction, field emission scanning electron microscopy, scanning probe microscopy and X-ray photoelectron spectroscopy. The photocatalytic activities were evaluated by measuring the decomposition rate of methylene blue under ultra violet and visible light. The antibacterial properties of the coatings were investigated against Escherichia coli, Staphylococcus aureus, Saccharomyces cerevisia and Aspergillus niger. The principle of incubation methods was also discussed. The results indicated that Fe doping of thin films eventuated in high antibacterial properties under visible light and this performance remained even after stoppage of illumination. This article tries to provide some explanation for this fact.

  20. Secretory ranalexin produced in recombinant Pichia pastoris exhibits additive or synergistic bactericidal activity when used in combination with polymyxin B or linezolid against multi-drug resistant bacteria.

    Science.gov (United States)

    Aleinein, Rasha Abou; Schäfer, Holger; Wink, Michael

    2014-01-01

    Ranalexin, a cationic peptide from frogs, is a potent therapeutic antimicrobial peptide (AMP). Its limited availability is an obstacle for a wider application. A high-level production of AMPs via bioengineering is possible but remains a challenging task. In the current study, we investigated the potential antibacterial properties of recombinant ranalexin, expressed in the yeast Pichia pastoris. A 78-bp DNA fragment encoding the mature ranalexin peptide with a 6-His tag on its C-terminus was designed using the preferred codon usage of P. pastoris. The gene was inserted into pPICZaA and transformed into competent cells of P. pastoris strain KM71. The yield of secretory ranalexin reached up to ~6 mg/L culture. Time-kill curve analysis of ranalexin against both Escherichia coli and methicillin-resistant Staphylococcus aureus (MRSA) demonstrated a concentration- dependent rapid bactericidal activity. In checkerboard assays, the combinations of ranalexin with the established antibiotics polymyxin B or linezolid reduced the MIC additively in most tested bacteria. Time-kill assays indicated a significant synergism in E. coli and MRSA when ranalexin was used in combination with antibiotics, even at concentrations of 1/4 MIC or 1/2 MIC of ranalexin, respectively. Thus we propose that secretory ranalexin produced in P. pastoris could be a useful tool to unravel ranalexin’s biological function and for use in future in vivo studies against multi- resistant bacterial infections.

  1. Exploring a new phenomenon in the bactericidal response of TiO2 thin films by Fe doping: Exerting the antimicrobial activity even after stoppage of illumination

    International Nuclear Information System (INIS)

    Naghibi, Sanaz; Vahed, Shohreh; Torabi, Omid; Jamshidi, Amin; Golabgir, Mohammad Hossein

    2015-01-01

    Graphical abstract: - Highlights: • Highly uniform Fe–TiO 2 thin films were deposited on glass using sol–gel hot-dipping technique. • The photocatalytic properties were studied upon UV and visible irradiation. • By Fe doping into TiO 2 structure, its microbial performance was prolonged even after stopping the illumination. • Due to Fe doping, the significant improvement in bactericidal coating was evident. - Abstract: Antibacterial properties of Fe-doped TiO 2 thin films prepared on glass by the sol–gel hot-dipping technique were studied. The films were characterized by X-ray diffraction, field emission scanning electron microscopy, scanning probe microscopy and X-ray photoelectron spectroscopy. The photocatalytic activities were evaluated by measuring the decomposition rate of methylene blue under ultra violet and visible light. The antibacterial properties of the coatings were investigated against Escherichia coli, Staphylococcus aureus, Saccharomyces cerevisia and Aspergillus niger. The principle of incubation methods was also discussed. The results indicated that Fe doping of thin films eventuated in high antibacterial properties under visible light and this performance remained even after stoppage of illumination. This article tries to provide some explanation for this fact

  2. Stem Bark Extract and Fraction of Persea americana (Mill. Exhibits Bactericidal Activities against Strains of Bacillus cereus Associated with Food Poisoning

    Directory of Open Access Journals (Sweden)

    David A. Akinpelu

    2014-12-01

    Full Text Available The study investigates the in vitro antibacterial potentials of stem bark extracts of Persea americana on strains of Bacillus cereus implicated in food poisoning. The crude stem bark extracts and butanolic fraction at a concentration of 25 mg/mL and 10 mg/mL, respectively, exhibited antibacterial activities against test isolates. The zones of inhibition exhibited by the crude extract and the fraction ranged between 10 mm and 26 mm, while the minimum inhibitory concentration values ranged between 0.78 and 5.00 mg/mL. The minimum bactericidal concentrations ranged between 3.12 mg/mL–12.5 mg/mL and 1.25–10 mg/mL for the extract and the fraction, respectively. The butanolic fraction killed 91.49% of the test isolates at a concentration of 2× MIC after 60 min of contact time, while a 100% killing was achieved after the test bacterial cells were exposed to the butanolic fraction at a concentration of 3× MIC after 90 min contact time. Intracellular protein and potassium ion leaked out of the test bacterial cells when exposed to certain concentrations of the fraction; this is an indication of bacterial cell wall disruptions by the extract’s butanolic fraction and, thus, caused a biocidal effect on the cells, as evident in the killing rate test results.

  3. Eco-friendly synthesis of silver and gold nanoparticles with enhanced bactericidal activity and study of silver catalyzed reduction of 4-nitrophenol.

    Science.gov (United States)

    Naraginti, Saraschandra; Sivakumar, A

    2014-07-15

    The present study reports a simple and robust method for synthesis of silver and gold nanoparticles using Coleus forskohlii root extract as reducing and stabilizing agent. Stable silver nanoparticles (AgNPs) and gold nanopoarticles (AuNPs) were formed on treatment of an aqueous silver nitrate (AgNO3) and chloroauric acid (HAuCl4) solutions with the root extract. The nanoparticles obtained were characterized by UV-Visible spectroscopy, Transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR). UV-Vis and TEM analysis indicate that with higher quantities of root extract, the interaction is enhanced leading to size reduction of spherical metal nanoparticles. XRD confirms face-centered cubic phase and the diffraction peaks can be attributed to (111), (200), (222) and (311) planes for these nanoparticles. These synthesized Ag and Au nanoparticles were found to exhibit excellent bactericidal activity against clinically isolated selected pathogens such as Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus). The synthesized AgNPs were also found to function as an efficient green catalyst in the reduction of anthropogenic pollutant 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) by sodium borohydride, which was apparent from the periodical color change from bright yellow to colorless, after the addition of AgNPs. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Eco-friendly synthesis of silver and gold nanoparticles with enhanced bactericidal activity and study of silver catalyzed reduction of 4-nitrophenol

    Science.gov (United States)

    Naraginti, Saraschandra; Sivakumar, A.

    2014-07-01

    The present study reports a simple and robust method for synthesis of silver and gold nanoparticles using Coleus forskohlii root extract as reducing and stabilizing agent. Stable silver nanoparticles (AgNPs) and gold nanopoarticles (AuNPs) were formed on treatment of an aqueous silver nitrate (AgNO3) and chloroauric acid (HAuCl4) solutions with the root extract. The nanoparticles obtained were characterized by UV-Visible spectroscopy, Transmission electron microscopy (TEM), X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FT-IR). UV-Vis and TEM analysis indicate that with higher quantities of root extract, the interaction is enhanced leading to size reduction of spherical metal nanoparticles. XRD confirms face-centered cubic phase and the diffraction peaks can be attributed to (1 1 1), (2 0 0), (2 2 2) and (3 1 1) planes for these nanoparticles. These synthesized Ag and Au nanoparticles were found to exhibit excellent bactericidal activity against clinically isolated selected pathogens such as Escherichia coli (E. coli), Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus). The synthesized AgNPs were also found to function as an efficient green catalyst in the reduction of anthropogenic pollutant 4-nitrophenol (4-NP) to 4-aminophenol (4-AP) by sodium borohydride, which was apparent from the periodical color change from bright yellow to colorless, after the addition of AgNPs.

  5. The absorbed dose to blood from blood-borne activity

    International Nuclear Information System (INIS)

    Hänscheid, H; Fernández, M; Lassmann, M

    2015-01-01

    The radiation absorbed dose to blood and organs from activity in the blood is relevant for nuclear medicine dosimetry and for research in biodosimetry. The present study provides coefficients for the average absorbed dose rates to the blood from blood-borne activity for radionuclides frequently used in targeted radiotherapy and in PET diagnostics. The results were deduced from published data for vessel radius-dependent dose rate coefficients and reasonable assumptions on the blood-volume distribution as a function of the vessel radius. Different parts of the circulatory system were analyzed separately. Vessel size information for heart chambers, aorta, vena cava, pulmonary artery, and capillaries was taken from published results of morphometric measurements. The remaining blood not contained in the mentioned vessels was assumed to reside in fractal-like vascular trees, the smallest branches of which are the arterioles or venules. The applied vessel size distribution is consistent with recommendations of the ICRP on the blood-volume distribution in the human. The resulting average absorbed dose rates to the blood per nuclear disintegration per milliliter (ml) of blood are (in 10 −11  Gy·s −1 ·Bq −1 ·ml) Y-90: 5.58, I-131: 2.49, Lu-177: 1.72, Sm-153: 2.97, Tc-99m: 0.366, C-11: 4.56, F-18: 3.61, Ga-68: 5.94, I-124: 2.55. Photon radiation contributes 1.1–1.2·10 −11  Gy·s −1 ·Bq −1 ·ml to the total dose rate for positron emitters but significantly less for the other nuclides. Blood self-absorption of the energy emitted by ß-particles in the whole blood ranges from 37% for Y-90 to 80% for Tc-99m. The correspondent values in vascular trees, which are important for the absorbed dose to organs, range from 30% for Y-90 to 82% for Tc-99m. (paper)

  6. GREATER HEMOCYTE BACTERICIDAL ACTIVITY IN OYSTERS (CRASSOSTREA VIRGINICA) FROM A RELATIVELY CONTAMINATED SITE IN PENSACOLA BAY, FLORIDA.

    Science.gov (United States)

    Bivalve mollusks such as Crassostrea virginica inhabiting polluted estuaries and coastal areas may bioaccumulate high concentrations of contaminants without apparent ill effects. However, changes in putative internal defense activities have been associated with contaminant accumu...

  7. In vitro bactericidal activity of 4- and 5-chloro-2-hydroxy-N-[1-oxo-1-(phenylamino)alkan-2-yl]benzamides against MRSA.

    Science.gov (United States)

    Zadrazilova, Iveta; Pospisilova, Sarka; Pauk, Karel; Imramovsky, Ales; Vinsova, Jarmila; Cizek, Alois; Jampilek, Josef

    2015-01-01

    A series of nine substituted 2-hydroxy-N-[1-oxo-1-(phenylamino)alkan-2-yl]benzamides was assessed as prospective bactericidal agents against three clinical isolates of methicillin-resistant Staphylococcus aureus (MRSA) and S. aureus ATCC 29213 as the reference and quality control strain. The minimum bactericidal concentration was determined by subculturing aliquots from MIC determination onto substance-free agar plates. The bactericidal kinetics of compounds 5-chloro-2-hydroxy-N-[(2S)-3-methyl-1-oxo-1-{[4-(trifluoromethyl)phenyl]amino}butan-2-yl]benzamide (1f), N-{(2S)-1-[(4-bromophenyl)amino]-3-methyl-1-oxobutan-2-yl}-4-chloro-2-hydroxybenzamide (1g), and 4-chloro-N-{(2S)-1-[(3,4-dichlorophenyl)amino]-3-methyl-1-oxobutan-2-yl}-2-hydroxybenzamide (1h) was established by time-kill assay with a final concentration of the compound equal to 1x, 2x, and 4x MIC; aliquots were removed at 0, 4, 6, 8, and 24 h time points. The most potent bactericidal agent was compound 1f exhibiting remarkable rapid concentration-dependent bactericidal effect even at 2x MIC at 4, 6, and 8 h (with a reduction in bacterial count ranging from 3.08 to 3.75 log10 CFU/mL) and at 4x MIC at 4, 6, 8, and 24 h (5.30 log10 CFU/mL reduction in bacterial count) after incubation against MRSA 63718. Reliable bactericidal effect against other strains was maintained at 4x MIC at 24 h.

  8. A comparison of the bactericidal effects and cytotoxic activity of three types of oxidizing water, prepared by electrolysis, as chemical dental plaque control agents.

    Science.gov (United States)

    Shimada, K; Ito, K; Murai, S

    2000-06-01

    Acid oxidizing water (AOW), neutral oxidizing water (NtOW) and acid oxidizing water with a low available chlorine concentration (AOW-LC) may be obtained by electrolyzing a solution of tap water containing various quantities of NaCl and HCl. This study compared the bactericidal effects of these waters on cariogenic and periodontopathogenic bacteria and their cytotoxicities against epithelial cells. AOW, NtOW and AOW-LC showed considerable bactericidal effects. The cytotoxicity of AOW-LC was significantly lower than the other solutions tested (Pplaque formation as conventional chemical plaque-control agents.

  9. Colloidal titania-silica-iron oxide nanocomposites and the effect from silica thickness on the photocatalytic and bactericidal activities

    Science.gov (United States)

    Chanhom, Padtaraporn; Charoenlap, Nisanart; Tomapatanaget, Boosayarat; Insin, Numpon

    2017-04-01

    New types of colloidal multifunctional nanocomposites that combine superparamagnetic character and high photocatalytic activity were synthesized and investigated. The superparamagnetic nanocomposites composed of anatase titania, silica, and iron oxide nanoparticles (TSI) were synthesized using thermal decomposition method followed by microemulsion method, without calcination at high temperature. Different techniques including X-ray diffraction (XRD) and transmission electron microscope (TEM) were used to characterize and confirm the structure of the nanocomposites. These nanocomposites showed high photocatalytic activity when used in the photodegradation of methylene blue under irradiation with a black light lamp. Moreover, the nanocomposites exhibited high antibacterial properties. From our study, the nanocomposites can be useful in various applications such as removal of pollutants with readily separation from the environment using an external magnetic field. These composites could effectively photo-degrade the dye at least three cycles without regeneration. The effects of silica shell thickness on the photocatalytic activity was investigated, and the thickness of 6 nm of the silica interlayer is enough for the inhibition of electron translocation between titania and iron oxide nanoparticles and maintaining the efficiency of photocatalytic activity of titania nanoparticles.

  10. Influence of ethylenediamine-n,n’-disuccinic acid (EDDS) concentration on the bactericidal activity of fatty acids in vitro

    Science.gov (United States)

    The antibacterial activity of mixtures of ethylenediamine-N,N’-disuccinic acid (EDDS) and antibacterial fatty acids (FA) was examined using the agar diffusion assay. Solutions of caproic, caprylic, capric, and lauric acids dissolved in potassium hydroxide (KOH) were supplemented with 0, 5, or 10 mM ...

  11. Bactericidal activity of the food color additive Phloxine B against Staphylococcus aureus and other food borne microbial pathogens

    Science.gov (United States)

    The spread of antibiotic resistance among Staphylococcus aureus strains requires the development of new anti S. aureus agents. The objective of this study was evaluating the antimicrobial activity of the food color additive Phloxine B against S. aureus and other food microbial pathogens. Our result ...

  12. INVOLVEMENT OF BACTERICIDAL FACTORS FROM THROMBIN-STIMULATED PLATELETS IN CLEARANCE OF ADHERENT VIRIDANS STREPTOCOCCI IN EXPERIMENTAL INFECTIVE ENDOCARDITIS

    NARCIS (Netherlands)

    VANDERWERFF, J; ZAAT, SAJ; JOLDERSMA, W; HESS, J

    Platelets activated with thrombin release bactericidal factors. We studied the role of the susceptibility of viridans streptococci to these bactericidal factors in the development of infective endocarditis (IE). By using the experimental endocarditis rabbit model, the initial adherence and the

  13. Visible light induced bactericidal and photocatalytic activity of hydrothermally synthesized BiVO4 nano-octahedrals.

    Science.gov (United States)

    Sharma, Rishabh; Uma; Singh, Sonal; Verma, Ajit; Khanuja, Manika

    2016-09-01

    In the present work, monoclinic bismuth vanadate (m-BiVO4) nanostructures have been synthesized via simple hydrothermal method and employed for visible light driven antimicrobial and photocatalytic activity. Morphology (octahedral) and size (200-300nm) of the m-BiVO4 are studied using transmission electron microscopy (TEM). The crystal structure of m-BiVO4 (monoclinic scheelite structure) is confirmed by high resolution-TEM (HRTEM) and X-ray diffraction (XRD) studies. The band gap of m-BiVO4 was estimated to be ca. 2.42eV through Kubelka-Munk function F(R∞) using diffuse reflectance spectroscopy (DRS). Antimicrobial action of m-BiVO4 is anticipated by (i) shake flask method, (ii) MTT [3-(4,5-Dimethylthiazol-2-Yl)-2,5-Diphenyltetrazolium Bromide] assay for cytotoxicity. SEM analysis has been carried on Escherichia coli (E.coli) before and after treatment with nanostructure materials to reveal the mechanism underlying the antimicrobial action. Antimicrobial activity is studied as a function of m-BiVO4 concentration viz. 20, 40, 60 and 80ppm. The bacterial growth is decreased 80% to 96%, with the increase in m-BiVO4 concentration from 20ppm to 80ppm, respectively, in 2h. Photocatalytic activity and rate kinetics of m-BiVO4 nanostructures have been studied as a function of time on methylene blue (MB) dye degradation which is one of the waste products of textile industries and responsible for water pollution. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Surface functional polymers by post-polymerization modification using diarylcarbenes: introduction, release and regeneration of hydrogen peroxide and bactericidal activity.

    Science.gov (United States)

    Griffiths, Jon-Paul; Maliha, Bushra; Moloney, Mark G; Thompson, Amber L; Hussain, Ishtiaq

    2010-09-07

    Functionalized diarylcarbenes are excellent reactive intermediates suitable for the direct surface modification of organic polymers, and these may be used to introduce urea and thiourea functions onto polystyrene at loading levels of up to 2.3 x 10(13) molecules/cm(2). These functions are capable of the reversible binding and release of peroxide at loading levels of up to 0.6 mmol/g and give polymers that display biocidal activity against a spectrum of gram-positive and gram-negative bacteria.

  15. Bactericidal activity of an imidazo[1, 2-a]pyridine using a mouse M. tuberculosis infection model.

    Directory of Open Access Journals (Sweden)

    Yong Cheng

    Full Text Available Tuberculosis remains a global threat due in part to the long treatment regimen and the increased prevalence of drug resistant M. tuberculosis strains. Therefore, new drug regimens are urgently required to combat this deadly disease. We previously synthesized and evaluated a series of new anti-tuberculosis compounds which belong to the family of imidazo[1,2-a]pyridines. This family of compounds showed low nM MIC (minimal inhibitory concentration values against M. tuberculosis in vitro. In this study, a derivative of imidazo[1,2-a]pyridines, (N-(4-(4-chlorophenoxybenzyl-2,7-dimethylimidazo[1,2-a]pyridine-3-carboxamide (ND-09759, was selected as a promising lead compound to determine its protective efficacy using a mouse infection model. Pharmacokinetic analysis of ND-09759 determined that at a dosage of 30 mg/kg mouse body weight (PO gave a maximum serum drug concentration (Cmax of 2.9 µg/ml and a half-life of 20.1 h. M. tuberculosis burden in the lungs and spleens was significantly decreased in mice treated once daily 6 days per week for 4-weeks with ND-09759 compared to untreated mice and this antibiotic activity was equivalent to isoniazid (INH and rifampicin (RMP, two first-line anti-TB drugs. We observed slightly higher efficacy when using a combination of ND-09759 with either INH or RMP. Finally, the histopathological analysis revealed that infected mice treated with ND-09759 had significantly reduced inflammation relative to untreated mice. In conclusion, our findings indicate ND-09759 might be a potent candidate for the treatment of active TB in combination with current standard anti-TB drugs.

  16. Blue light treatment of Pseudomonas aeruginosa: Strong bactericidal activity, synergism with antibiotics and inactivation of virulence factors.

    Science.gov (United States)

    Fila, Grzegorz; Kawiak, Anna; Grinholc, Mariusz Stanislaw

    2017-08-18

    Pseudomonas aeruginosa is among the most common pathogens responsible for both acute and chronic infections of high incidence and severity. Additionally, P. aeruginosa resistance to conventional antimicrobials has increased rapidly over the past decade. Therefore, it is crucial to explore new therapeutic options, particularly options that specifically target the pathogenic mechanisms of this microbe. The ability of a pathogenic bacterium to cause disease is dependent upon the production of agents termed 'virulence factors', and approaches to mitigate these agents have gained increasing attention as new antibacterial strategies. Although blue light irradiation is a promising alternative approach, only limited and preliminary studies have described its effect on virulence factors. The current study aimed to investigate the effects of lethal and sub-lethal doses of blue light treatment (BLT) on P. aeruginosa virulence factors. We analyzed the inhibitory effects of blue light irradiation on the production/activity of several virulence factors. Lethal BLT inhibited the activity of pyocyanin, staphylolysin, pseudolysin and other proteases, but sub-lethal BLT did not affect the production/expression of proteases, phospholipases, and flagella- or type IV pili-associated motility. Moreover, a eukaryotic cytotoxicity test confirmed the decreased toxicity of blue light-treated extracellular P. aeruginosa fractions. Finally, the increased antimicrobial susceptibility of P. aeruginosa treated with sequential doses of sub-lethal BLT was demonstrated with a checkerboard test. Thus, this work provides evidence-based proof of the susceptibility of drug-resistant P. aeruginosa to BLT-mediated killing, accompanied by virulence factor reduction, and describes the synergy between antibiotics and sub-lethal BLT.

  17. Extracellular synthesis of silver nanoparticles by novel Pseudomonas veronii AS41G inhabiting Annona squamosa L. and their bactericidal activity

    Science.gov (United States)

    Baker, Syed; Mohan Kumar, K.; Santosh, P.; Rakshith, D.; Satish, S.

    2015-02-01

    In present investigation extracellular synthesis of silver nanoparticles were synthesized using cell free supernatant of Pseudomonas veronii AS41G isolated from Annona squamosa L. The bacterium significantly reduced silver nitrate to generate silver nanoparticles which was characterized with hyphenated techniques. Synthesis of silver nanoparticles preliminary confirmed by UV-Visible spectrophotometry with the intense peak at 410 nm, Further FTIR analysis revealed the possible role of biomolecules in the supernatant responsible for mediating the nanoparticles formation. The XRD spectra exhibited the characteristic Bragg peaks of 1 0 0, 1 1 1, 2 0 0, and 2 2 0 facets of the face centred cubic symmetry of nanoparticles suggesting that these nanoparticles were crystalline in nature. TEM microgram showed polydispersity of nanoparticles with size ranging from 5 to 50 nm. Synthesized silver nanoparticles showed antibacterial activity against human and environmental pathogens including MRSA. The study enlightens the role of biosynthesized silver nanoparticles as an emerging alternative for drug resistant microorganisms. The obtained results are promising enough to pave the environmentally benign nanoparticle synthesis processes without use of any toxic chemicals and also envision the emerging role of endophytes towards synthesis of nanoparticles. With scanty reports available on P.veronii species, a new role has been reported in this study which will be very valuable for future researchers working on it.

  18. Bactericidal Activity of Copper Oxide Nanocomposite/Bioglass for in Vitro Clindamycin Release in Implant Infections Due to Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Alijanian

    2016-08-01

    Full Text Available Background In recent years, bioactive bioceramics such as bioglass and hydroxyapatite (HA have been introduced as a remarkable development in the field of medicine due to their bio-adaptability, non-toxicity, and persistence, in vivo. They have many potential applications in the repair of bone defects and hence they have attracted significant interest from scholars. Objectives The aim of this study was to synthesize inorganic matrix CuO-based bioglasses and evaluate their antibacterial activity against aerobic bacterial infections in bone implants. Methods Nano-composite samples of silica-based bioactive glass, 60S BG with nano-powder CuO, were synthesized using the sol-gel method and then assessed with regard to their antibacterial properties against Staphylococcus aureus using well diffusion agar. The samples included BG58S (58%SiO2, 36%CaO, 6%P2O5, BG/10CuO (58%SiO2, 26%CaO, 6%P2O5, 10%CuO, and BG/20CuO (48%SiO2, 26%CaO, 6%P2O5, 20%CuO. To evaluate their bioactivity, the prepared samples of BG/20CuO, BG/10CuO, and BG58S were immersed in simulated body fluids (SBF. The surface morphology and structure of the samples before and after immersion in the SBF were characterized using scanning electron microscopy (SEM and Fourier transform infrared (FTIR, respectively. Then, the BG/20CuO and BG/10CuO samples were loaded in clindamycin, an antibiotic widely used in the treatment of osteomyelitis, and their release profiles were studied in phosphate buffer solution. Results It was observed that the growth inhibition zone increased through clindamycin release due to the increasing CuO percentage in the nanocomposite of bioactive glass. The bioactivity of the nanocomposite/bioglass with CuO was superior to that of bioglass alone. In this study, the BG/20CuO sample showed a sustained release of clindamycin, which is sufficient for a drug delivery system. Conclusions Increasing the Cu nanoparticles in bioactive glass samples leads to the release of Cu2

  19. Bactericidal and Hemocompatible Coating via the Mixed-Charged Copolymer.

    Science.gov (United States)

    Fan, Xiao-Li; Hu, Mi; Qin, Zhi-Hui; Wang, Jing; Chen, Xia-Chao; Lei, Wen-Xi; Ye, Wan-Ying; Jin, Qiao; Ren, Ke-Feng; Ji, Jian

    2018-03-28

    Cationic antibacterial coating based on quaternary ammonium compounds, with an efficient and broad spectrum bactericidal property, has been widely used in various fields. However, the high density of positive charges tends to induce weak hemocompatibility, which hinders the application of the cationic antibacterial coating in blood-contacting devices and implants. It has been reported that a negatively charged surface can reduce blood coagulation, showing improved hemocompatibility. Here, we describe a strategy to combine the cationic and anionic groups by using mixed-charged copolymers. The copolymers of poly (quaternized vinyl pyridine- co- n-butyl methacrylate- co-methacrylate acid) [P(QVP- co- nBMA- co-MAA)] were synthesized through free radical copolymerization. The cationic group of QVP, the anionic group of MAA, and the hydrophobic group of nBMA were designed to provide bactericidal capability, hemocompatibility, and coating stability, respectively. Our findings show that the hydrophilicity of the copolymer coating increased, and its zeta potential decreased from positive charge to negative charge with the increase of the anionic/cationic ratio. Meanwhile, the bactericidal property of the copolymer coating was kept around a similar level compared with the pure quaternary ammonium copolymer coating. Furthermore, the coagulation time, platelet adhesion, and hemolysis tests revealed that the hemocompatibility of the copolymer coating improved with the addition of the anionic group. The mixed-charged copolymer combined both bactericidal property and hemocompatibility and has a promising potential in blood-contacting antibacterial devices and implants.

  20. In vitro and in vivo bactericidal activity of Tinospora sagittata (Oliv.) Gagnep. var. craveniana (S.Y.Hu) Lo and its main effective component, palmatine, against porcine Helicobacter pylori

    OpenAIRE

    Rong, Qian; Xu, Min; Dong, Qi; Zhang, Yuli; Li, Yinglun; Ye, Gang; Zhao, Ling

    2016-01-01

    Background Tinospora sagittata (Oliv.) Gagnep. var. craveniana (S.Y.Hu) Lo (TSG) is a traditional Chinese herb that has been used for the treatment of upper respiratory tract infection and has anti-bacterial and anti-ulcer activity. Our study investigated the bactericidal effects of TSG and its major component, palmatine, against a Helicobacter pylori (H. pylori) strain isolated from pig and the standard strain H. pylori SS1 in vitro and in vivo. Methods H. pylori was isolated from pig and na...

  1. In vitro and in vivo bactericidal activity of Tinospora sagittata (Oliv.) Gagnep. var. craveniana (S.Y.Hu) Lo and its main effective component, palmatine, against porcine Helicobacter pylori.

    Science.gov (United States)

    Rong, Qian; Xu, Min; Dong, Qi; Zhang, Yuli; Li, Yinglun; Ye, Gang; Zhao, Ling

    2016-08-30

    Tinospora sagittata (Oliv.) Gagnep. var. craveniana (S.Y.Hu) Lo (TSG) is a traditional Chinese herb that has been used for the treatment of upper respiratory tract infection and has anti-bacterial and anti-ulcer activity. Our study investigated the bactericidal effects of TSG and its major component, palmatine, against a Helicobacter pylori (H. pylori) strain isolated from pig and the standard strain H. pylori SS1 in vitro and in vivo. H. pylori was isolated from pig and named H. pylori SCYA201401. For in vitro experiments, the inhibitory activity of TSG and palmatine against H. pylori SCYA201401 and H. pylori SS1 were tested by use of the agar cup diffusion technique. The minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) were determined from the absence of H. pylori colonies on agar plates. Time-kill curves were used to evaluate bactericidal activity; the average number of colonies was calculated at 0 to 48 h after liquid incubation, with concentrations of drugs at 0.5, 1, and 2 × MIC. For in vivo experiments, H. pylori SCYA201401-infected mice were randomly divided into TSG, palmatine, triple therapy (omeprazole, clarithromycin, and amoxicillin), blank control, and model groups. The eradication ratios were determined by use of rapid urease tests and bacterial culture. In vitro, the MIC and MBC of TSG against H. pylori SCYA201401 and SS1 were both 6250 μg/mL, whereas palmatine against H. pylori SCYA201401 was 6.25 μg/mL and against H. pylori SS1 was 3.12 μg/mL. The time-kill curves showed a dose-dependent, progressive decline in the numbers of viable bacteria up to 40 h. In vivo, the eradication ratios in the TSG and palmatine groups of mice were 80 and 50 % compared with 70 % in the triple-therapy group. TSG and its major component, palmatine, have bactericidal activity against H. pylori in vitro and in vivo. The possibility that TSG or palmatine can be effective in the treatment of human and animals H. pylori

  2. Bactericidal and Cytotoxic Activities of Polyphenol Extracts from Solanum tuberosum spp. tuberosum and spp. andigena Cultivars on Escherichia coli and Human Neuroblastoma SH-SY5Y Cells In Vitro

    Directory of Open Access Journals (Sweden)

    María Ximena Silveyra

    2018-01-01

    Full Text Available Potatoes (Solanum tuberosum L. are a good source of dietary antioxidant polyphenols. This study investigated the potential antioxidant, bactericidal, and cytotoxic activities in vitro of the phenolic compounds present in tubers of one S. tuberosum spp. tuberosum (Summerside, and three S. tuberosum spp. andigena (landraces Moradita, Waicha, and Santa María cultivars. Both the content of phenolic acids, chlorogenic acids (CGAs being the most abundant, and the antioxidant activity were higher in extracts from skin than from flesh. Extracts from Moradita flesh and Summerside skin showed bactericidal activity against Escherichia coli ATCC 25922 but failed to inhibit pathogenic E. coli O157. Both extracts lack pigmentation but do contain 5-CGA, caffeic, and ferulic acids. Positive control with gentamicin and commercial 5-CGA resulted in a complete inhibition of bacterial growth. In addition, all potato extracts and commercial 5-CGA diminished dose-dependently human neuroblastoma SH-SY5Y cell viability. Skin extracts were more potent than flesh extracts. Among flesh extracts, Moradita was the most potent. Together, our results suggest that Moradita flesh could provide a desirable source of important health-promoting substances. Findings indicate that the biological activity of potato extracts is a combination of various bioactive compounds and contribute to the revalorization of potato as a functional food.

  3. Contact activation of blood-plasma coagulation

    Science.gov (United States)

    Golas, Avantika

    Surface engineering of biomaterials with improved hemocompatibility is an imperative, given the widespread global need for cardiovascular devices. Research summarized in this dissertation focuses on contact activation of FXII in buffer and blood plasma frequently referred to as autoactivation. The extant theory of contact activation imparts FXII autoactivation ability to negatively charged, hydrophilic surfaces. According to this theory, contact activation of plasma involves assembly of proteins comprising an "activation complex" on activating surfaces mediated by specific chemical interactions between complex proteins and the surface. This work has made key discoveries that significantly improve our core understanding of contact activation and unravel the existing paradigm of plasma coagulation. It is shown herein that contact activation of blood factor XII (FXII, Hageman factor) in neat-buffer solution exhibits a parabolic profile when scaled as a function of silanized-glass-particle activator surface energy (measured as advancing water adhesion tension t°a=g° Iv costheta in dyne/cm, where g°Iv is water interfacial tension in dyne/cm and theta is the advancing contact angle). Nearly equal activation is observed at the extremes of activator water-wetting properties --36 < t°a < 72 dyne/cm (O° ≤ theta < 120°), falling sharply through a broad minimum within the 20 < t°a < 40 dyne/cm (55° < theta < 75°). Furthermore, contact activation of FXII in buffer solution produces an ensemble of protein fragments exhibiting either procoagulant properties in plasma (proteolysis of blood factor XI or prekallikrein), amidolytic properties (cleavage of s-2302 chromogen), or the ability to suppress autoactivation through currently unknown biochemistry. The relative proportions of these fragments depend on activator surface chemistry/energy. We have also discovered that contact activation is moderated by adsorption of plasma proteins unrelated to coagulation through an

  4. Bactericidal and antineoplastic effect of combination of norfloxacin and adriamycin.

    Science.gov (United States)

    Castelli, M; Barbieri, M L; Bertolini, A; Bossa, R; Galatulas, I

    1987-01-01

    Norfloxacin and adriamycin were tested alone and in combination for bactericidal activity against different strains of gram-negative bacteria. The antitumoral effect of a combination of norfloxacin and adriamycin was determined in mice bearing Ehrlich ascites carcinoma and in mice bearing P 388 leukemia. No interference with the antibacterial activity of norfloxacin or with the antitumoral activity of adriamycin was observed.

  5. Does bipolar pacemaker current activate blood platelets?

    DEFF Research Database (Denmark)

    Gjesdal, Grunde; Hansen, Annebirthe Bo; Brandes, Axel

    2009-01-01

    to the pacemaker can. METHODS: Platelet-rich plasma was prepared from two healthy subjects. Platelet reactivity to the agonist ADP was tested in paired samples in an aggregometer in a case/control setup. RESULTS: Eighteen of 46 tested pairs of platelet-rich plasma showed increased reactivity in the paced sample......OBJECTIVE: The aim of this study was to investigate whether bipolar pacemaker current lead can activate blood platelets. The null hypothesis was that 1 minute of electrical stimulation of platelets would not influence their subsequent reactivity to adenosine diphosphate (ADP). BACKGROUND: Both...... platelets and muscle cells contain actin and myosin filaments, and both cells are activated following calcium influx. Muscle cells open their calcium channels and contract when exposed to an electric current. Current through a bipolar pacemaker lead will expose a small volume of blood, including platelets...

  6. Antagonism between Bacteriostatic and Bactericidal Antibiotics Is Prevalent

    Science.gov (United States)

    Lázár, Viktória; Papp, Balázs; Arnoldini, Markus; Abel zur Wiesch, Pia; Busa-Fekete, Róbert; Fekete, Gergely; Pál, Csaba; Ackermann, Martin; Bonhoeffer, Sebastian

    2014-01-01

    Combination therapy is rarely used to counter the evolution of resistance in bacterial infections. Expansion of the use of combination therapy requires knowledge of how drugs interact at inhibitory concentrations. More than 50 years ago, it was noted that, if bactericidal drugs are most potent with actively dividing cells, then the inhibition of growth induced by a bacteriostatic drug should result in an overall reduction of efficacy when the drug is used in combination with a bactericidal drug. Our goal here was to investigate this hypothesis systematically. We first constructed time-kill curves using five different antibiotics at clinically relevant concentrations, and we observed antagonism between bactericidal and bacteriostatic drugs. We extended our investigation by performing a screen of pairwise combinations of 21 different antibiotics at subinhibitory concentrations, and we found that strong antagonistic interactions were enriched significantly among combinations of bacteriostatic and bactericidal drugs. Finally, since our hypothesis relies on phenotypic effects produced by different drug classes, we recreated these experiments in a microfluidic device and performed time-lapse microscopy to directly observe and quantify the growth and division of individual cells with controlled antibiotic concentrations. While our single-cell observations supported the antagonism between bacteriostatic and bactericidal drugs, they revealed an unexpected variety of cellular responses to antagonistic drug combinations, suggesting that multiple mechanisms underlie the interactions. PMID:24867991

  7. Electrospun biodegradable polymers loaded with bactericide agents

    Directory of Open Access Journals (Sweden)

    Ramaz Katsarava

    2016-03-01

    Full Text Available Development of materials with an antimicrobial activity is fundamental for different sectors, including medicine and health care, water and air treatment, and food packaging. Electrospinning is a versatile and economic technique that allows the incorporation of different natural, industrial, and clinical agents into a wide variety of polymers and blends in the form of micro/nanofibers. Furthermore, the technique is versatile since different constructs (e.g. those derived from single electrospinning, co-electrospinning, coaxial electrospinning, and miniemulsion electrospinning can be obtained to influence the ability to load agents with different characteristics and stability and to modify the release behaviour. Furthermore, antimicrobial agents can be loaded during the electrospinning process or by a subsequent coating process. In order to the mitigate burst release effect, it is possible to encapsulate the selected drug into inorganic nanotubes and nanoparticles, as well as in organic cyclodextrine polysaccharides. In the same way, processes that involve covalent linkage of bactericide agents during surface treatment of electrospun samples may also be considered. The present review is focused on more recent works concerning the electrospinning of antimicrobial polymers. These include chitosan and common biodegradable polymers with activity caused by the specific load of agents such as metal and metal oxide particles, quaternary ammonium compounds, hydantoin compounds, antibiotics, common organic bactericides, and bacteriophages.

  8. The role of anti-NHba antibody in bactericidal activity elicited by the meningococcal serogroup B vaccine, MenB-4C.

    Science.gov (United States)

    Partridge, Elizabeth; Lujan, Eduardo; Giuntini, Serena; Vu, David M; Granoff, Dan M

    2017-07-24

    MenB-4C (Bexsero®) is a multicomponent serogroup B meningococcal vaccine. For vaccine licensure, efficacy was inferred from serum bactericidal antibody (SBA) against three antigen-specific indicator strains. The bactericidal role of antibody to the fourth vaccine antigen, Neisserial Heparin binding antigen (NHba), is incompletely understood. We identified nine adults immunized with two or three doses of MenB-4C who had sufficient volumes of sera and >3-fold increases in SBA titer against a strain with high NHba expression, which was mismatched with the other three MenB-4C antigens that elicit SBA. Using 1month-post-immunization sera we measured the effect of depletion of anti-NHba and/or anti-Factor H binding protein (FHbp) antibodies on SBA. Against three strains matched with the vaccine only for NHba, depletion of anti-NHba decreased SBA titers by an average of 43-79% compared to mock-adsorbed sera (Pvaccine antigen), depletion of anti-FHbp antibodies also decreased SBA by 45-64% (Pvaccine antigen, depletion of anti-NHba decreased SBA by an average of 26%, compared to mock-adsorbed sera (Panti-FHbp antibody decreased SBA by 92% (PAnti-NHba antibody can contribute to SBA elicited by MenB-4C, particularly in concert with anti-FHbp antibody. However, some high NHba-expressing strains are resistant, even with an exact match between the amino acid sequence of the vaccine and strain antigens. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Bactericidal effect of photocatalytically-active nanostructured TiO2surfaces on biofilms of the early oral colonizer, Streptococcus oralis.

    Science.gov (United States)

    Westas, Emma; Hayashi, Mariko; Cecchinato, Francesca; Wennerberg, Ann; Andersson, Martin; Jimbo, Ryo; Davies, Julia R

    2017-08-01

    This study evaluated the photocatalytic bactericidal effect of nanostructured anatase-rich titanium dioxide (TiO 2 ) on microbial biofilms. Commercially pure titanium discs were spin-coated with photocatalytic TiO 2 nanoparticles (P25). Uncoated discs were used as control (CTRL). Half of the CTRL and half of the P25-coated surfaces were coated with purified saliva (SAL) to give four different groups (CTRL, CTRL + SAL, P25 and P25 + SAL). Streptococcus oralis were allowed to form biofilms on the discs for 18 h and non-adherent cells were rinsed off. Bacterial viability was assessed at time 0 with Live/Dead BacLight staining and epifluorescence microscopy. The remaining discs were divided into a non-UV group and UVA-irradiated (+UV) group (irradiation time, 6 or 24 h). Thereafter, viability was assessed as above. Viability at time 0 was high and no dead cells were seen on any of the surfaces, even after 24 h, in the absence of UVA. However, after 24 h of exposure, the proportion of viable cells was reduced by 40% on the P25 discs compared to 0 and 6 h, and this effect was enhanced with a salivary pellicle. Members of mixed species biofilms differ in their susceptibility to the bactericidal effect of the surfaces tested and further investigations are needed to optimize the conditions. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2321-2328, 2017. © 2017 Wiley Periodicals, Inc.

  10. Moth eye mimetic cytocompatible bactericidal nanotopography: A convergent design.

    Science.gov (United States)

    Viela, Felipe; Navarro-Baena, Iván; Hernández, Jaime J; Osorio, Manuel R; Rodriguez, Isabel

    2018-01-19

    The rapid emergence of antibiotic resistant bacteria has prompted the need for radically different approaches to combat bacterial infections. Among these, bioinspired surface topographies have emerged as an effective sustainable strategy to deter bacterial infection. This study demonstrates the bactericidal activity and cytocompatibility of the moth eye mimetic topography produced by thermal polymer nanoimprinting. The moth eye topography was found to have bactericidal capabilities against Gram negative and Gram positive bacteria. Electron microscopy imaging revealed the bactericidal effect caused by mechanical rupture of the bacteria wall inflicted by the topography on the adhered cells. The cytocompatibility of the surfaces was evidenced by assessing the proliferation and morphology of keratinocytes cultured on the nanotopography. The technology meets important needs in medical implant technology for materials that not only have good biocompatibility but also antibacterial properties for reducing the risk of infections and related health complications. © 2018 IOP Publishing Ltd.

  11. Bactericidal activites of selected macrofungi extracts against Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Nikolovska-Nedelkoska Daniela A.

    2017-01-01

    Full Text Available The increasing of the antibiotic resistance exhibited by pathogenic microorganisms has resulted in research directed toward evaluation of novel sources of antimicrobial compounds. Previous studies have indicated that macrofungi, as a specific response to the natural hostile environment, produce secondary metabolites with antimicrobial properties. In this study, antimicrobial activities of the extracts from six wild mushrooms: Amanita echinocephala, Russula medulata, Cerena unicolor, Hericium erinaceus, Ishnoderma benzoinum and Laetiporus sulphureus were evaluated against Grampositive bacterium Staphylococcus aureus. The antimicrobial potential of the methanolic mushroom extracts was investigated by the microdilution method. Antimicrobial activity was observed in all species included in the study. All the extracts that demonstrated inhibitory activities were further tested for bactericidal activity and minimum bactericidal concentration (MBC values were determined. The tested microorganism was most sensitive to the examined extracts from the polypore fungi C. unicolor and H. erinaceus. The highest bactericidal activity was obtained in the extracts from the species C. unicolor (MBC=1.563 mg/mL. The experimental results revealed that the methanolic extract of C. unicolor possessed significant bactericidal activity. The findings suggest the potential use of this wild mushroom as antimicrobial agent.

  12. Cerebral blood flow response to functional activation

    DEFF Research Database (Denmark)

    Paulson, Olaf B; Hasselbalch, Steen G; Rostrup, Egill

    2010-01-01

    Cerebral blood flow (CBF) and cerebral metabolic rate are normally coupled, that is an increase in metabolic demand will lead to an increase in flow. However, during functional activation, CBF and glucose metabolism remain coupled as they increase in proportion, whereas oxygen metabolism only...... most distant from the capillaries, whereas other studies point to a shift toward a higher degree of non-oxidative glucose consumption during activation. In this review, we argue that the key mechanism responsible for the regional CBF (rCBF) increase during functional activation is a tight coupling...... between rCBF and glucose metabolism. We assert that uncoupling of rCBF and oxidative metabolism is a consequence of a less pronounced increase in oxygen consumption. On the basis of earlier studies, we take into consideration the functional recruitment of capillaries and attempt to accommodate...

  13. Bactericidal Permeability-Increasing Proteins Shape Host-Microbe Interactions

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    Fangmin Chen

    2017-04-01

    Full Text Available We characterized bactericidal permeability-increasing proteins (BPIs of the squid Euprymna scolopes, EsBPI2 and EsBPI4. They have molecular characteristics typical of other animal BPIs, are closely related to one another, and nest phylogenetically among invertebrate BPIs. Purified EsBPIs had antimicrobial activity against the squid’s symbiont, Vibrio fischeri, which colonizes light organ crypt epithelia. Activity of both proteins was abrogated by heat treatment and coincubation with specific antibodies. Pretreatment under acidic conditions similar to those during symbiosis initiation rendered V. fischeri more resistant to the antimicrobial activity of the proteins. Immunocytochemistry localized EsBPIs to the symbiotic organ and other epithelial surfaces interacting with ambient seawater. The proteins differed in intracellular distribution. Further, whereas EsBPI4 was restricted to epithelia, EsBPI2 also occurred in blood and in a transient juvenile organ that mediates hatching. The data provide evidence that these BPIs play different defensive roles early in the life of E. scolopes, modulating interactions with the symbiont.

  14. Bactericidal antibiotics induce programmed metabolic toxicity

    Directory of Open Access Journals (Sweden)

    Aislinn D. Rowan

    2016-03-01

    Full Text Available The misuse of antibiotics has led to the development and spread of antibiotic resistance in clinically important pathogens. These resistant infections are having a significant impact on treatment outcomes and contribute to approximately 25,000 deaths in the U.S. annually. If additional therapeutic options are not identified, the number of annual deaths is predicted to rise to 317,000 in North America and 10,000,000 worldwide by 2050. Identifying therapeutic methodologies that utilize our antibiotic arsenal more effectively is one potential way to extend the useful lifespan of our current antibiotics. Recent studies have indicated that modulating metabolic activity is one possible strategy that can impact the efficacy of antibiotic therapy. In this review, we will address recent advances in our knowledge about the impacts of bacterial metabolism on antibiotic effectiveness and the impacts of antibiotics on bacterial metabolism. We will particularly focus on two studies, Lobritz, et al. (PNAS, 112(27: 8173-8180 and Belenky et al. (Cell Reports, 13(5: 968–980 that together demonstrate that bactericidal antibiotics induce metabolic perturbations that are linked to and required for bactericidal antibiotic toxicity.

  15. Parenteral nutrition suppresses the bactericidal response of the small intestine.

    Science.gov (United States)

    Omata, Jiro; Pierre, Joseph F; Heneghan, Aaron F; Tsao, Francis H C; Sano, Yoshifumi; Jonker, Mark A; Kudsk, Kenneth A

    2013-01-01

    Parenteral nutrition (PN) increases infectious risk in critically ill patients compared with enteral feeding. Previously, we demonstrated that PN feeding suppresses the concentration of the Paneth cell antimicrobial protein secretory phospholipase A2 (sPLA2) in the gut lumen. sPLA2 and other Paneth cell proteins are released in response to bacterial components, such as lipopolysaccharide (LPS), and they modulate the intestinal microbiome. Because the Paneth cell protein sPLA2 was suppressed with PN feeding, we hypothesized PN would diminish the responsiveness of the small bowel to LPS through reduced secretions and as a result exhibit less bactericidal activity. The distal ileum was harvested from Institute of Cancer Research mice, washed, and randomized for incubation with LPS (0, 1, or 10 μg/mL). Culture supernatant was collected and sPLA2 activity was measured. Bactericidal activity of the ileum segment secretions was assessed against Pseudomonas aeruginosa with and without an sPLA2 inhibitor at 2 concentrations, 100 nmol/L and 1 μmol/L. Institute of Cancer Research mice were randomized to chow or PN for 5 days. Tissue was collected for immunohistochemistry (IHC) and ileal segments were incubated with LPS (0 or 10 μg/mL). sPLA2 activity and bactericidal activity were measured in secretions from ileal segments. Ileal segments responded to 10 μg/mL LPS with significantly greater sPLA2 activity and bactericidal activity. The bactericidal activity of secretions from LPS stimulated tissue was suppressed 50% and 70%, respectively, with the addition of the sPLA2-inhibitor. Chow displayed greater sPLA2 in the Paneth cell granules and secreted higher levels of sPLA2 than PN before and after LPS. Accordingly, media collected from chow was more bactericidal than PN. IHC confirmed a reduction in Paneth cell granules after PN. This work demonstrates that ileal segments secrete bactericidal secretions after LPS exposure and the inhibition of the Paneth cell antimicrobial

  16. Short Communication A study on the bactericidal effect of nisin ...

    African Journals Online (AJOL)

    Nisin, the best known LAB (Lactic Acid Bacteria) bacteriocin, is a promising alternative to antibiotics, and displays a broad spectrum of activity against a wide range of spoilage and pathogenic Gram positive bacteria. The aim of the study was to determine the bactericidal effect of nisin. The Lactococcus lactis MTCC 440 used ...

  17. Mutacin II, a Bactericidal Lantibiotic from Streptococcus mutans

    NARCIS (Netherlands)

    Chikindas, Michael L.; Novák, Jan; Driessen, Arnold J.M.; Konings, Wilhelmus; Schilling, Kurt M.; Caufield, Page W.

    1995-01-01

    Mutacin II is a lantibiotic that is produced by group II Streptococcus mutans, it inhibits the growth of other streptococci as well as many other gram-positive microorganisms by a hitherto unknown mechanism, Mutacin LI possesses bactericidal activity against susceptible cells. It transiently

  18. Bactericidal Activity of Aqueous Acrylic Paint Dispersion for Wooden Substrates Based on TiO2 Nanoparticles Activated by Fluorescent Light

    Directory of Open Access Journals (Sweden)

    Diana Di Gioia

    2013-08-01

    Full Text Available The photocatalytic effect of TiO2 has great potential for the disinfection of surfaces. Most studies reported in the literature use UV activation of TiO2, while visible light has been used only in a few applications. In these studies, high concentrations of TiO2, which can compromise surface properties, have been used. In this work, we have developed an acrylic-water paint dispersion containing low TiO2 content (2 vol % for the inactivation of microorganisms involved in hospital-acquired infections. The nanoparticles and the coating have been characterized using spectroscopic techniques and transmission electron microscopy, showing their homogenous dispersion in the acrylic urethane coating. A common fluorescent light source was used to activate the photocatalytic activity of TiO2. The paint dispersion showed antimicrobial activity against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. The coating containing the TiO2 nanoparticles maintained good UV stability, strong adhesion to the substrate and high hardness. Therefore, the approach used is feasible for paint formulation aimed at disinfection of healthcare surfaces.

  19. Bactericidal Activity of Aqueous Acrylic Paint Dispersion for Wooden Substrates Based on TiO2 Nanoparticles Activated by Fluorescent Light

    OpenAIRE

    Zuccheri, Tommaso; Colonna, Martino; Stefanini, Ilaria; Santini, Cecilia; Gioia, Diana

    2013-01-01

    The photocatalytic effect of TiO2 has great potential for the disinfection of surfaces. Most studies reported in the literature use UV activation of TiO2, while visible light has been used only in a few applications. In these studies, high concentrations of TiO2, which can compromise surface properties, have been used. In this work, we have developed an acrylic-water paint dispersion containing low TiO2 content (2 vol %) for the inactivation of microorganisms involved in hospital-acquired inf...

  20. Human milk bactericidal properties: effect of lyophilization and relation to maternal factors and milk components.

    Science.gov (United States)

    Salcedo, Jaime; Gormaz, Maria; López-Mendoza, Maria C; Nogarotto, Elisabetta; Silvestre, Dolores

    2015-04-01

    Lyophilization appears to be a viable method for storing human milk, assuring no microbiological contamination and preserving its health benefits and antibacterial properties. The aim of the study is to evaluate and compare the effects of different storage methods (lyophilization and freezing at -20°C and -80°C) and maternal factors (gestational length or time postpartum) upon the microbiological contents and bactericidal activity of human milk. The possible relation between bactericidal activity and the content of certain nutrients and functional components is also investigated. Microbiological content, bactericidal activity, sialic acid, and ganglioside contents, as well as protein, fat, and lactose concentrations were assessed in 125 human milk samples from 65 healthy donors in the Human Milk Bank of La Fe (Valencia, Spain). Lyophilization and storage at -80°C significantly reduced the content of mesophilic aerobic microorganisms and Staphylococcus epidermidis when compared with storage at -20°C. Bactericidal activity was not significantly modified by lyophilization when compared with freezing at either -20°C or -80°C. Bactericidal activity was not correlated with fat, protein, or lactose content, but was significantly correlated to ganglioside content. The bactericidal activity was significantly greater (P bactericidal capacities, being a feasible alternative for human milk banks.

  1. Characterization and relative photonic efficiencies of a new nanocarbon/TiO2 composite photocatalyst designed for organic dye decomposition and bactericidal activity

    International Nuclear Information System (INIS)

    Oh, Won-Chun; Jung, Ah-Reum; Ko, Weon-Bae

    2009-01-01

    Two kinds of nanocarbon/TiO 2 composite photocatalysts were synthesized using an MCPBA oxidation method, employing MWCNT (multi-wall carbon nanotubes) and C 60 as nanocarbon sources and TNB (titanium (IV) n-butoxide) as a titanium dioxide source. From the XRD patterns of the composites, structural variations revealed the C 60 /TiO 2 composite having a mixture of anatase and rutile forms, with the MWCNT/TiO 2 composite presenting only the anatase phase. Elemental analysis indicated a predominance of carbon and Ti metal peaks over any other element. From the SEM results, the TiO 2 particles were dispersed regularly on the fullerene surface with large clusters bearing irregular agglomerate dispersions. However, the MWCNT/TiO 2 showed homogenous distributions with only individual MWCNT, covered with TiO 2 and without any jam-like aggregates between the two. According to the photocatalytic results, the relationship of the -ln (c/c 0 ) of the solution products of the organic dye, methylene blue (MB), as a function of time under UV irradiation, showed linearity properties with first-order kinetics and an excellent photodegradation effect. From the measured bactericidal effects, the inhibition zone was defined by the halo method with the curves of E. coli inactivation denoting effectiveness of the nanocarbon/TiO 2 composites in the sunlight.

  2. The effects of chronic inorganic and organic phosphate exposure on bactericidal activity of the coelomic fluid of the sea urchin Lytechinus variegatus (Lamarck) (Echinodermata: Echinoidea).

    Science.gov (United States)

    Böttger, S Anne; McClintock, James B

    2009-07-01

    The sea urchin Lytechinus variegatus can survive chronic exposure to sodium phosphate (inorganic phosphate) concentrations as high as 3.2 mg L-1, and triethyl phosphate (organic phosphate) concentrations of 1000 mg L-1. However, chronic exposure to low (0.8 mg L-1 inorganic and 10 mg L-1 organic phosphate), medium (1.6 mg L-1 inorganic and 100 mg L-1 organic phosphate) or high (3.2 mg L-1 inorganic and 1000 mg L-1 organic phosphate) sublethal concentrations of these phosphates inhibit bactericidal clearance of the marine bacterium Vibrio sp. Bacteria were exposed to coelomic fluid collected from individuals maintained in either artificial seawater, or three concentrations of either inorganic phosphate or organic phosphate. Sterile marine broth, natural seawater and cell free coelomic fluid (cfCF) were employed as controls. Bacterial survival indices were measured at 0, 24 and 48 h periods once a week for four weeks. Bacteria were readily eliminated from the whole coelomic fluid (wCF) of individuals maintained in artificial seawater. Individuals maintained in inorganic phosphates were able to clear bacteria following a two week exposure period, while individuals maintained at even low concentrations of organic phosphates failed to clear all bacteria from their coelomic fluid. Exposure to phosphates represses antimicrobial defenses and may ultimately compromise survival of L. variegatus in the nearshore environment.

  3. Ecto-ATPase activity of vertebrate blood cells.

    Science.gov (United States)

    Bencic, D C; Yates, T J; Ingermann, R L

    1997-01-01

    Ecto-ATPase activity was measured for red blood cells, white blood cells, and whole blood from a variety of vertebrates. A large range of red blood cell ecto-ATPase activity was observed; for example, at 10 degrees C, red blood cells from a catastomid fish (Catostomus macrocheilus) and a newt (Taricha rivularis) had activities of 56 +/- 9 and 25,000,000 +/- 14,000,000 pmol ATP per 10(6) red blood cells per hour, respectively (mean +/- SD). Several control experiments verified that the measured ATPase activity was not the result of intracellular ATPases released due to cell damage or lysis nor due to the release of intracellular nucleoside triphosphate or uptake of extracellular ATP. Red blood cell ecto-ATPase activity was relatively low within the teleosts, was high within the reptiles, and had the greatest range and single highest value within the amphibians. Within the endotherms, avian red blood cell ecto-ATPase activities were greater than mammalian red blood cell ecto-ATPase activities, which were the lowest for all vertebrates examined. The lowest ecto-ATPase activities measured were for human and skunk red blood cells, which had activities of 13 +/- 1 and 11 +/- 2 pmol ATP per 10(6) red blood cells per hour, respectively, at 35 degrees C. Ecto-ATPase activity was measured in white blood cells of several vertebrate species and appeared generally high and less variable than red blood cell ecto-ATPase activity. Measured whole blood ecto-ATPase activity showed a range of three orders of magnitude and correlated positively with red blood cell ecto-ATPase activities. Ecto-ATPase activity was also determined for red blood cells from fetal, 1-3 d old neonatal, and pregnant garter snakes (Thamnophis elegans); these activities were not significantly different from the activity of red blood cells from nonpregnant adult females. Overall, the data from the present study demonstrate a wide range of red blood cell and whole blood ecto-ATPase activities among vertebrates

  4. Nanodiamonds activate blood platelets and induce thromboembolism.

    Science.gov (United States)

    Kumari, Sharda; Singh, Manoj K; Singh, Sunil K; Grácio, José J A; Dash, Debabrata

    2014-03-01

    Nanodiamonds (NDs) have been evaluated for a wide range of biomedical applications. Thus, thorough investigation of the biocompatibility of NDs has become a research priority. Platelets are highly sensitive and are one of the most abundant cell types found in blood. They have a central role in hemostasis and arterial thrombosis. In this study, we aim to investigate the direct and acute effects of carboxylated NDs on platelet function. In this study, pro-coagulant parameters such as platelet aggregability, intracellular Ca(2+) flux, mitochondrial transmembrane potential (ΔΨm), generation of reactive oxygen species, surface exposure of phosphatidylserine, electron microscopy, cell viability assay and in vivo thromboembolism were analyzed in great detail. Carboxylated NDs evoked significant activation of human platelets. When administered intravenously in mice, NDs were found to induce widespread pulmonary thromboembolism, indicating the remarkable thrombogenic potential of this nanomaterial. Our findings raise concerns regarding the putative biomedical applications of NDs pertaining to diagnostics and therapeutics, and their toxicity and prothrombotic properties should be critically evaluated.

  5. Bovine milk intake and xanthine oxidase activity in blood serum.

    Science.gov (United States)

    McCarthy, R D; Long, C A

    1976-06-01

    Xanthine oxidase activity in blood serum was measured by a sensitive radio-enzymatic assay. Pigs receiving 7.6 liters of milk daily for 100 days did not show any detectable enzymatic activity in their blood Xanthine oxidase activity in blood serum of 25 human volunteers had an average of 6.7 milliunits per liter with a range of 0 to 34.6 milliunits per liter. Neither a causal nor statistically significant relationship existed between xanthine oxidase activity in blood and average daily milk consumption, age, or sex.

  6. Bactericidal performance of nanostructured surfaces by fluorocarbon plasma.

    Science.gov (United States)

    Vassallo, E; Pedroni, M; Silvetti, T; Morandi, S; Toffolatti, S; Angella, G; Brasca, M

    2017-11-01

    This study presents the characterization and antibacterial activity of nanostructured Si by plasma treatment method using a tetrafluoromethane (CF 4 ) and hydrogen (H 2 ) mixture. Nanostructured-Si is a synthetic nanomaterial that contains high aspect ratio nanoprotrusions on its surface, produced through a reactive-ion etching process. We have shown that the nanoprotrusions on the surfaces produce a mechanical bactericidal effect. Nanostructured-Si exhibited notable activity against three different microorganisms: Gram-negative (Escherichia coli), Gram-positive (Staphylococcus aureus) and spore-forming bacteria (Bacillus cereus) producing a > 5 log 10 reduction after 24h of incubation. Scanning electron microscopy was used to analysis the structure and morphology character of different surfaces evidencing the physical bactericidal activity of the Nanostructured-Si. These results provide excellent prospects for the development of a new generation of antibacterial surfaces. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. A multi-defense strategy: Enhancing bactericidal activity of a medical grade polymer with a nitric oxide donor and surface-immobilized quaternary ammonium compound.

    Science.gov (United States)

    Pant, Jitendra; Gao, Jing; Goudie, Marcus J; Hopkins, Sean P; Locklin, Jason; Handa, Hitesh

    2017-08-01

    Although the use of biomedical devices in hospital-based care is inevitable, unfortunately, it is also one of the leading causes of the nosocomial infections, and thus demands development of novel antimicrobial materials for medical device fabrication. In the current study, a multi-defense mechanism against Gram-positive and Gram-negative bacteria is demonstrated by combining a nitric oxide (NO) releasing agent with a quaternary ammonium antimicrobial that can be covalently grafted to medical devices. Antibacterial polymeric composites were fabricated by incorporating an NO donor, S-nitroso-N-acetyl-penicillamine (SNAP) in CarboSil® polymer and top coated with surface immobilized benzophenone based quaternary ammonium antimicrobial (BPAM) small molecule. The results suggest that SNAP and BPAM individually have a different degree of toxicity towards Gram-positive and Gram-negative bacteria, while the SNAP-BPAM combination is effective in reducing both types of adhered viable bacteria equally well. SNAP-BPAM combinations reduced the adhered viable Pseudomonas aeruginosa by 99.0% and Staphylococcus aureus by 99.98% as compared to the control CarboSil films. Agar diffusion tests demonstrate that the diffusive nature of NO kills bacteria beyond the direct point of contact which the non-leaching BPAM cannot achieve alone. This is important for potential application in biofilm eradication. The live-dead bacteria staining shows that the SNAP-BPAM combination has more attached dead bacteria (than live) as compared to the controls. The SNAP-BPAM films have increased hydrophilicity and higher NO flux as compared to the SNAP films useful for preventing blood protein and bacterial adhesion. Overall the combination of SNAP and BPAM imparts different attributes to the polymeric composite that can be used in the fabrication of antimicrobial surfaces for various medical device applications. A significant increase in the biomedical device related infections (BDRIs), inability of

  8. Methemoglobin reductase activity in intact fish red blood cells

    DEFF Research Database (Denmark)

    Jensen, Frank B; Nielsen, Karsten

    2018-01-01

    Red blood cells (RBCs) possess methemoglobin reductase activity that counters the ongoing oxidation of hemoglobin (Hb) to methemoglobin (metHb), which in circulating blood is caused by Hb autoxidation or reactions with nitrite. We describe an assay for determining metHb reductase activity in intact...

  9. Effect of physical activity on controlling blood pressure among ...

    African Journals Online (AJOL)

    Background: A variety of lifestyle modifications including weight loss in the overweight and physical activity have been shown in clinical trials to lower blood pressure in hypertensive patients. Objective: To demonstrate the effect of physical activity on controlling blood pressure among hypertensive patients from Mishref area ...

  10. Effect of blood activity on dosimetric calculations for radiopharmaceuticals

    Science.gov (United States)

    Zvereva, Alexandra; Petoussi-Henss, Nina; Li, Wei Bo; Schlattl, Helmut; Oeh, Uwe; Zankl, Maria; Graner, Frank Philipp; Hoeschen, Christoph; Nekolla, Stephan G.; Parodi, Katia; Schwaiger, Markus

    2016-11-01

    The objective of this work was to investigate the influence of the definition of blood as a distinct source on organ doses, associated with the administration of a novel radiopharmaceutical for positron emission tomography-computed tomography (PET/CT) imaging—(S)-4-(3-18F-fluoropropyl)-L-glutamic acid (18F-FSPG). Personalised pharmacokinetic models were constructed based on clinical PET/CT images from five healthy volunteers and blood samples from four of them. Following an identifiability analysis of the developed compartmental models, person-specific model parameters were estimated using the commercial program SAAM II. Organ doses were calculated in accordance to the formalism promulgated by the Committee on Medical Internal Radiation Dose (MIRD) and the International Commission on Radiological Protection (ICRP) using specific absorbed fractions for photons and electrons previously derived for the ICRP reference adult computational voxel phantoms. Organ doses for two concepts were compared: source organ activities in organs parenchyma with blood as a separate source (concept-1); aggregate activities in perfused source organs without blood as a distinct source (concept-2). Aggregate activities comprise the activities of organs parenchyma and the activity in the regional blood volumes (RBV). Concept-1 resulted in notably higher absorbed doses for most organs, especially non-source organs with substantial blood contents, e.g. lungs (92% maximum difference). Consequently, effective doses increased in concept-1 compared to concept-2 by 3-10%. Not considering the blood as a distinct source region leads to an underestimation of the organ absorbed doses and effective doses. The pronounced influence of the blood even for a radiopharmaceutical with a rapid clearance from the blood, such as 18F-FSPG, suggests that blood should be introduced as a separate compartment in most compartmental pharmacokinetic models and blood should be considered as a distinct source in

  11. Palmitoleic acid calcium salt: a lubricant and bactericidal powder from natural lipids.

    Science.gov (United States)

    Yamamoto, Yoshiaki; Kawamura, Yuki; Yamazaki, Yuki; Kijima, Tatsuro; Morikawa, Toshiya; Nonomura, Yoshimune

    2015-01-01

    Palmitoleic acid is a promising bactericidal agent for cleansing products with alternative bactericidal abilities. In this study, we focus on the physical and biological activity of palmitoleic acid calcium salt (C16:1 fatty acid Ca salt) because it forms via an ion-exchange reaction between palmitoleic acid and Ca ions in tap water, and remains on the skin surface during the cleansing process. Here, we prepared C16:1 fatty acid Ca salt to investigate its crystal structure and physical and bactericidal properties. The Ca salt was a plate-shaped lamellar crystalline powder with a particle diameter of several micrometers to several tens of micrometers; it exhibited significant lubricity and alternative bactericidal activity against Staphylococcus aureus (S. aureus) and Propionibacterium acnes (P. acnes). We also examined other fatty acid Ca salts prepared from lauric acid (C12:0 fatty acid), palmitic acid (C16:0 fatty acid), and oleic acid (C18:1 fatty acid). The bactericidal activities and lubricity of the fatty acid Ca salts changed with the alkyl chain length and the degree of unsaturation. The C16:1 fatty acid Ca salt exhibited the strongest selective bactericidal ability among the four investigated fatty acid Ca salts. These findings suggest that C16:1 fatty acid and its Ca salt have potential applications in cleansing and cosmetic products.

  12. Diastereomeric bactericidal effect of Ru(phenanthroline)2dipyridophenazine.

    Science.gov (United States)

    Mårtensson, Anna K F; Bergentall, Mattias; Tremaroli, Valentina; Lincoln, Per

    2016-11-01

    Metal susceptibility assays and spot plating were used to investigate the antimicrobial activity of enantiopure [Ru(phen) 2 dppz] 2+ (phen =1,10-phenanthroline and dppz = dipyrido[3,2-a:2´,3´-c]phenazine) and [μ-bidppz(phen) 4 Ru 2 ] 4 + (bidppz =11,11´-bis(dipyrido[3,2-a:2´,3´-c]phenazinyl)), on Gram-negative Escherichia coli and Gram-positive Bacillus subtilis as bacterial models. The minimum inhibitory concentrations (MIC) and minimum bactericidal concentrations (MBC) were determined for both complexes: while [μ-bidppz(phen) 4 Ru 2 ] 4 + only showed a bactericidal effect at the highest concentrations tested, the antimicrobial activity of [Ru(phen) 2 dppz] 2+ against B. subtilis was comparable to that of tetracyline. In addition, the Δ-enantiomer of [Ru(phen) 2 dppz] 2+ showed a 2-fold higher bacteriostatic and bactericidal effect compared to the Λ-enantiomer. This was in accordance with the enantiomers relative binding affinity for DNA, thus strongly indicating DNA binding as the mode of action. © 2016 Wiley Periodicals, Inc.

  13. Blood Volume Response to Physical Activity and Inactivity

    Science.gov (United States)

    2007-07-01

    deconditioning effects of bed rest inactivity are independent of any disease state. The impor- tance of physical activity on reversing the effects of inactivity...Blood Volume Response to Physical Activity and Inactivity VICTOR A. CONVERTINO, PHD ABSTRACT: Data from both cross-sectional and longitu- dinal...studies provide compelling evidence that circulat- ing blood volume can be influenced by regular physical activity or inactivity. Expansion or contraction

  14. Bactericidal Effects of Natural Nanotopography of Dragonfly Wing on Escherichia coli.

    Science.gov (United States)

    Bandara, Chaturanga D; Singh, Sanjleena; Afara, Isaac O; Wolff, Annalena; Tesfamichael, Tuquabo; Ostrikov, Kostya; Oloyede, Adekunle

    2017-03-01

    Nanotextured surfaces (NTSs) are critical to organisms as self-adaptation and survival tools. These NTSs have been actively mimicked in the process of developing bactericidal surfaces for diverse biomedical and hygiene applications. To design and fabricate bactericidal topographies effectively for various applications, understanding the bactericidal mechanism of NTS in nature is essential. The current mechanistic explanations on natural bactericidal activity of nanopillars have not utilized recent advances in microscopy to study the natural interaction. This research reveals the natural bactericidal interaction between E. coli and a dragonfly wing's (Orthetrum villosovittatum) NTS using advanced microscopy techniques and proposes a model. Contrary to the existing mechanistic models, this experimental approach demonstrated that the NTS of Orthetrum villosovittatum dragonfly wings has two prominent nanopillar populations and the resolved interface shows membrane damage occurred without direct contact of the bacterial cell membrane with the nanopillars. We propose that the bacterial membrane damage is initiated by a combination of strong adhesion between nanopillars and bacterium EPS layer as well as shear force when immobilized bacterium attempts to move on the NTS. These findings could help guide the design of novel biomimetic nanomaterials by maximizing the synergies between biochemical and mechanical bactericidal effects.

  15. Comparative Study on Liver Enzymes Activity and Blood Group ...

    African Journals Online (AJOL)

    The aim of this study is to determine the activities of some selected liver enzymes amongst apparently healthy subjects of different blood groups. The study involved 95 apparently healthy students of Ambrose Alli University, Ekpoma, Edo State, Nigeria, between the ages of 18-30, and distributed as follows; blood group O ...

  16. Blood Glucose Lowering Activities Of Seed Of Persea Americana On ...

    African Journals Online (AJOL)

    The n-hexane, chloroform and methanol extracts of Persea americana seeds obtained by cold maceration were assessed for blood glucose lowering activity using two doses of alloxan. The different extracts caused significant blood glucose lowering effect than the glibenclamide in the single dose alloxanized rats but in the ...

  17. Use of agar diffusion assay to measure bactericidal activity of alkaline salts of fatty acids against bacteria associated with poultry processing

    Science.gov (United States)

    The agar diffusion assay was used to examine antibacterial activity of alkaline salts of caproic, caprylic, capric, lauric, and myristic acids. A 0.5M concentration of each fatty acid was dissolved in 1.0 M potassium hydroxide (KOH), and pH of the mixtures was adjusted to 10.5 with citric acid. Solu...

  18. Use of agar diffusion assay to evaluate bactericidal activity of formulations of alkaline salts of fatty acids against bacteria associated with poultry processing

    Science.gov (United States)

    The agar diffusion assay was used to examine antibacterial activity of alkaline salts of fatty acids (FA). Wells in agar media seeded with bacteria were filled with FA-potassium hydroxide (KOH) solutions, plates were incubated, and zones of inhibition were measured. The relationship between bacteric...

  19. Creatine kinase activity is associated with blood pressure

    NARCIS (Netherlands)

    Brewster, Lizzy M.; Mairuhu, Gideon; Bindraban, Navin R.; Koopmans, Richard P.; Clark, Joseph F.; van Montfrans, Gert A.

    2006-01-01

    BACKGROUND: We previously hypothesized that high activity of creatine kinase, the central regulatory enzyme of energy metabolism, facilitates the development of high blood pressure. Creatine kinase rapidly provides adenosine triphosphate to highly energy-demanding processes, including cardiovascular

  20. Survival and function of phagocytes in blood culture media

    DEFF Research Database (Denmark)

    Fischer, T K; Prag, J; Kharazmi, A

    1999-01-01

    The survival and function of human phagocytes in sterile aerobic and anaerobic blood culture media were investigated using neutrophil morphology, white blood cell count in a haemoanalyser, flow cytometry, oxidative burst response, and bactericidal effect in Colorbact and Septi-Chek blood culture...... media and Bact/Alert. When comparing agitation to stationary incubation no difference in phagocytic activity was found. The methods showed the same trends demonstrating that the phagocytes' viability and activity were prolonged by oxygen and shortened by anaerobic conditions and sodium polyethanol...... sulfonate (SPS). Best preserved activity and viability were found in the aerobic media containing less than 0.5 g/l SPS, in which significant phagocyte oxidative burst and bactericidal activity were found up to 4 days after inoculation. Considering that the majority of bacteremias are due to aerobic...

  1. Activation of blood coagulation in cancer: implications for tumour progression

    Science.gov (United States)

    Lima, Luize G.; Monteiro, Robson Q.

    2013-01-01

    Several studies have suggested a role for blood coagulation proteins in tumour progression. Herein, we discuss (1) the activation of the blood clotting cascade in the tumour microenvironment and its impact on primary tumour growth; (2) the intravascular activation of blood coagulation and its impact on tumour metastasis and cancer-associated thrombosis; and (3) antitumour therapies that target blood-coagulation-associated proteins. Expression levels of the clotting initiator protein TF (tissue factor) have been correlated with tumour cell aggressiveness. Simultaneous TF expression and PS (phosphatidylserine) exposure by tumour cells promote the extravascular activation of blood coagulation. The generation of blood coagulation enzymes in the tumour microenvironment may trigger the activation of PARs (protease-activated receptors). In particular, PAR1 and PAR2 have been associated with many aspects of tumour biology. The procoagulant activity of circulating tumour cells favours metastasis, whereas the release of TF-bearing MVs (microvesicles) into the circulation has been correlated with cancer-associated thrombosis. Given the role of coagulation proteins in tumour progression, it has been proposed that they could be targets for the development of new antitumour therapies. PMID:23889169

  2. Physical activity, body mass index and blood pressure in primary ...

    African Journals Online (AJOL)

    Background: Lack of physical activity contributes to overweight and obesity. It is recommended that children accumulate at least one hour of moderate to vigorous intensity physical activity daily. Objective: The level of physical activity, body mass index (BMI) and blood pressure (BP) were evaluated in pupils attending private ...

  3. Blood-group-Ii-active gangliosides of human erythrocyte membranes

    International Nuclear Information System (INIS)

    Feizi, T.; Childs, R.A.; Hakomori, S.-I.; Powell, M.E.

    1978-01-01

    More than ten new types of gangliosides, in addition to haematoside and sialosylparagloboside, were isolated from human erythrocyte membranes. These were separated by successive chromatographies on DAEA-Sephadex, on porous silica-gel columns and on thin-layer silica gel as acetylated compounds. Highly potent blood-group-Ii and moderate blood-group-H activities were demonstrated in some of the ganglioside fractions. The gangliosides incorporated into chlolesterol/phosphatidylcholine liposomes stoicheiometrically inhibited binding of anti-(blood-group-I and i) antibodies to a radioiodinated blood-group-Ii-active glycoprotein. The fraction with the highest blood-group-I activity, I(g) fraction, behaved like sialosyl-deca- to dodeca-glycosylceramides on t.l.c. Certain blood-group-I and most of the i-determinants were in partially or completely cryptic form and could be unmasked by sialidase treatment. Thus the I and i antigens, which are known to occur on internal structures of blood-group-ABH-active glycoproteins in secretions, also occur in the interior of the carbohydrate chains of erythrocyte gangliosides. (author)

  4. CatB is Critical for Total Catalase Activity and Reduces Bactericidal Effects of Phenazine-1-Carboxylic Acid on Xanthomonas oryzae pv. oryzae and X. oryzae pv. oryzicola.

    Science.gov (United States)

    Pan, Xiayan; Wu, Jian; Xu, Shu; Duan, Yabing; Zhou, Mingguo

    2017-02-01

    Rice bacterial leaf blight, caused by Xanthomonas oryzae pv. oryzae, and rice bacterial leaf streak, caused by X. oryzae pv. oryzicola, are major diseases of rice. Phenazine-1-carboxylic acid (PCA) is a natural product that is isolated from Pseudomonas spp. and is used to control many important rice diseases in China. We previously reported that PCA disturbs the redox balance, which results in the accumulation of reactive oxygen species in X. oryzae pv. oryzae. In this study, we found that PCA significantly upregulated the transcript levels of catB and katE, which encode catalases, and that PCA sensitivity was reduced when X. oryzae pvs. oryzae and oryzicola were cultured with exogenous catalase. Furthermore, catB deletion mutants of X. oryzae pvs. oryzae and oryzicola showed dramatically decreased total catalase activity, increased sensitivity to PCA, and reduced virulence in rice. In contrast, deletion mutants of srpA and katG, which also encode catalases, exhibited little change in PCA sensitivity. The results indicate that catB in both X. oryzae pvs. oryzae and oryzicola encodes a catalase that helps protect the bacteria against PCA-induced stress.

  5. Bactericidal Antibiotics Induce Mitochondrial Dysfunction and Oxidative Damage in Mammalian Cells

    Science.gov (United States)

    Costello, James C.; Liesa, Marc; Morones-Ramirez, J Ruben; Slomovic, Shimyn; Molina, Anthony; Shirihai, Orian S.; Collins, James J.

    2013-01-01

    Prolonged antibiotic treatment can lead to detrimental side effects in patients, including ototoxicity, nephrotoxicity, and tendinopathy, yet the mechanisms underlying the effects of antibiotics in mammalian systems remain unclear. It has been suggested that bactericidal antibiotics induce the formation of toxic reactive oxygen species (ROS) in bacteria. We show that clinically relevant doses of bactericidal antibiotics—quinolones, aminoglycosides, and β-lactams—cause mitochondrial dysfunction and ROS overproduction in mammalian cells. We demonstrate that these bactericidal antibiotic–induced effects lead to oxidative damage to DNA, proteins, and membrane lipids. Mice treated with bactericidal antibiotics exhibited elevated oxidative stress markers in the blood, oxidative tissue damage, and up-regulated expression of key genes involved in antioxidant defense mechanisms, which points to the potential physiological relevance of these antibiotic effects. The deleterious effects of bactericidal antibiotics were alleviated in cell culture and in mice by the administration of the antioxidant N-acetyl-L-cysteine or prevented by preferential use of bacteriostatic antibiotics. This work highlights the role of antibiotics in the production of oxidative tissue damage in mammalian cells and presents strategies to mitigate or prevent the resulting damage, with the goal of improving the safety of antibiotic treatment in people. PMID:23825301

  6. Natural and bioinspired nanostructured bactericidal surfaces.

    Science.gov (United States)

    Tripathy, Abinash; Sen, Prosenjit; Su, Bo; Briscoe, Wuge H

    2017-10-01

    Bacterial antibiotic resistance is becoming more widespread due to excessive use of antibiotics in healthcare and agriculture. At the same time the development of new antibiotics has effectively ground to a hold. Chemical modifications of material surfaces have poor long-term performance in preventing bacterial build-up and hence approaches for realising bactericidal action through physical surface topography have become increasingly important in recent years. The complex nature of the bacteria cell wall interactions with nanostructured surfaces represents many challenges while the design of nanostructured bactericidal surfaces is considered. Here we present a brief overview of the bactericidal behaviour of naturally occurring and bio-inspired nanostructured surfaces against different bacteria through the physico-mechanical rupture of the cell wall. Many parameters affect this process including the size, shape, density, rigidity/flexibility and surface chemistry of the surface nanotextures as well as factors such as bacteria specificity (e.g. gram positive and gram negative) and motility. Different fabrication methods for such bactericidal nanostructured surfaces are summarised. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  7. 21 CFR 1240.10 - Effective bactericidal treatment.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Effective bactericidal treatment. 1240.10 Section... DISEASES General Provisions § 1240.10 Effective bactericidal treatment. Whenever, under the provisions of this part, bactericidal treatment is required, it shall be accomplished by one or more of the following...

  8. Bactericidal, Bacteriolytic, and Antibacterial Virulence Activities of ...

    African Journals Online (AJOL)

    Tropical Journal of Pharmaceutical Research is indexed by Science Citation Index (SciSearch), Scopus,. International Pharmaceutical Abstract, Chemical Abstracts, Embase, Index Copernicus, EBSCO, African. Index Medicus, JournalSeek, Journal Citation Reports/Science Edition, Directory of Open Access Journals.

  9. Analysis of the Bactericidal Response to an Experimental Neisseria meningitidis Vesicle Vaccine

    Science.gov (United States)

    Moran, Elizabeth E.; Burden, Robert; Labrie, Joseph E.; Wen, Zhiyun; Wang, Xin-Min; Zollinger, Wendell D.; Zhang, Lan

    2012-01-01

    Rabbit immunogenicity studies on an experimental trivalent native outer membrane vesicle vaccine derived from three serogroup B strains were conducted to evaluate the effectiveness of this vaccine at inducing an antibody response with serum bactericidal activity against meningococcal strains of other serogroups in addition to serogroup B strains. The results showed that the vaccine was capable of inducing an effective broad-based bactericidal antibody response in rabbits against a small sample of Neisseria meningitidis strains of serogroups C, W135, and X and, to a lesser extent, serogroups A and Y. Analysis of antibody specificity using a bactericidal depletion assay revealed that antibodies to lipooligosaccharide (LOS), PorA, and NadA induced in rabbits by the experimental trivalent outer membrane vesicle vaccine were responsible for most of the bactericidal activity against strains of the other N. meningitidis serogroups. In the case of serogroup A N. meningitidis strains, the outer membrane antigen NadA was primarily responsible for protection. The outer membrane antigens fHbp and OpcA were also effective in removing some bactericidal activity from the sera. PMID:22461527

  10. [Aerobic physical activity lowers blood pressure in hypertension].

    Science.gov (United States)

    Börjesson, Mats; Onerup, Aron; Lundqvist, Stefan; Dahlöf, Björn

    2015-11-17

    Hypertension is one of the most important modifiable risk factors for cardiovascular morbidity and mortality. Physical inactivity plays a role in the development of (essential) hypertension. Increased physical activity may decrease the blood pressure in hypertensive individuals with 12/5 mm Hg (evidence grade +++ according to GRADE). A moderate/vigorous-intensity aerobic physical activity, at least 3 x 40-60 minutes/week, for 8 weeks, has the strongest evidence (evidence grade +++). Isometric (static) training may also decrease the blood pressure significantly (evidence grade ++).

  11. Kidney Rehabilitation Technology by Improving Blood Flow and Nerve Activation

    International Nuclear Information System (INIS)

    Mohd Jamil Hashim

    2016-01-01

    The rehabilitation of kidney is impossible from doctors point of view. Kidney failure happens when nephron in kidney fail to filter blood and water. Two major causes of kidney failure. First is the shrinkage of kidney and the second is the blockage of kidney medulla. Kidney shrinkage is because nephron damage due to long term diabetes (Nephrology expert point of view). Whereas blockage of kidney is due to food consume which in turn build up deposit at the blood duct connecting to the medulla. Experiment specimen own body. The rehabilitation methodology is to build up your blood flow system and nerve activation. Result from the study is through analyzing blood components such as creatinine, hemoglobin, urea and potassium. Conclusion, creatinine value has lowered and kidney shrinkage has normalize to its original size. It is hopeful I regain my health 100 % when my GFR reading achieved below 100. (author)

  12. Polyhexamethylene guanidine hydrochloride shows bactericidal advantages over chlorhexidine digluconate against ESKAPE bacteria.

    Science.gov (United States)

    Zhou, Zhongxin; Wei, Dafu; Lu, Yanhua

    2015-01-01

    More information regarding the bactericidal properties of polyhexamethylene guanidine hydrochloride (PHMG) against clinically important antibiotic-resistant ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens needs to be provided for its uses in infection control. The bactericidal properties of PHMG and chlorhexidine digluconate (CHG) were compared based on their minimum inhibitory concentrations (MICs), minimum bactericidal concentrations, and time-course-killing curves against clinically important antibiotic-susceptible and antibiotic-resistant ESKAPE pathogens. Results showed that PHMG exhibited significantly higher bactericidal activities against methicillin-resistant Staphylococcus aureus, carbapenem-resistant Klebsiella pneumoniae, and ceftazidime-resistant Enterobacter spp. than CHG. A slight bactericidal advantage over CHG was obtained against vancomycin-resistant Enterococcus faecium, ciprofloxacin- and levofloxacin-resistant Acinetobacter spp., and multidrug-resistant Pseudomonas aeruginosa. In previous reports, PHMG had higher antimicrobial activity against almost all tested Gram-negative bacteria and several Gram-positive bacteria than CHG using MIC test. These studies support the further development of covalently bound PHMG in sterile-surface materials and the incorporation of PHMG in novel disinfectant formulas. © 2014 International Union of Biochemistry and Molecular Biology, Inc.

  13. Aminotransferases and Leucine Aminopeptidase Activity in Blood Plasma of Chickens

    International Nuclear Information System (INIS)

    Kraljevic, P.; Stojevic, Z.; Milinkovic-Tur, S.; Simpraga, M.; Miljanic, S.

    1998-01-01

    It has been reported that irradiation of mammals by gama-rays cause increase of some enzyme activity in their blood plasma (Miller and Gates 1949; Milch and Albaum 1959; Hughes 1958; Miholjcic et al. 1979). In our previous papers (Kraljevic et al., 1982; Kraljevic and Emanovic 1993) it has been shown that activities of some enzymes in the blood plasma of chickens after an intramuscular injection of radioactive isotope 32 P. In this paper an attempt has been made to investigate the influence of gamma-ray irradiation of the whole body of chickens upon activity of some enzymes in their blood plasma. We also wanted to investigate whether the activity of aspartate-aminotransferase (AST), alanine aminotransferase (ALT) and leucine-aminopeptidase (LAP) may serve as an additional test for functional liver damage in chickens caused by gamma-ray. Fifty day old hybrid male chickens of heavy Jata breeds were irradiated by gamma-ray in the dose of 7,23±0,95 Gy. Blood samples were taken from the wing vein on days 1, 3, 5, 7, 9 and 15 after irradiation. Activity of AST, ALT, and LAP in the blood plasma were determined spectrophotometrically using Boehringer Mannheim GmbH optimized kits. At the end of the experiment all birds were sacrificed and, as well as died birds were photomorphologically and histologically investigated. The obtained results showed decrease of activity of all three enzymes during the whole period of investigation, but significant decrease showed only AST and LAP. It seems that both enzymes may serve as additional test for functional liver damage in chickens by external gamma-rays. (author)

  14. Bactericidal Effects and Mechanism of Action of Olanexidine Gluconate, a New Antiseptic

    Science.gov (United States)

    Iwata, Koushi; Nii, Takuya; Nakata, Hikaru; Tsubotani, Yoshie; Inoue, Yasuhide

    2015-01-01

    Olanexidine gluconate [1-(3,4-dichlorobenzyl)-5-octylbiguanide gluconate] (development code OPB-2045G) is a new monobiguanide compound with bactericidal activity. In this study, we assessed its spectrum of bactericidal activity and mechanism of action. The minimal bactericidal concentrations of the compound for 30-, 60-, and 180-s exposures were determined with the microdilution method using a neutralizer against 320 bacterial strains from culture collections and clinical isolates. Based on the results, the estimated bactericidal olanexidine concentrations with 180-s exposures were 869 μg/ml for Gram-positive cocci (155 strains), 109 μg/ml for Gram-positive bacilli (29 strains), and 434 μg/ml for Gram-negative bacteria (136 strains). Olanexidine was active against a wide range of bacteria, especially Gram-positive cocci, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci, and had a spectrum of bactericidal activity comparable to that of commercial antiseptics, such as chlorhexidine and povidone-iodine. In vitro experiments exploring its mechanism of action indicated that olanexidine (i) interacts with the bacterial surface molecules, such as lipopolysaccharide and lipoteichoic acid, (ii) disrupts the cell membranes of liposomes, which are artificial bacterial membrane models, (iii) enhances the membrane permeability of Escherichia coli, (iv) disrupts the membrane integrity of S. aureus, and (v) denatures proteins at relatively high concentrations (≥160 μg/ml). These results indicate that olanexidine probably binds to the cell membrane, disrupts membrane integrity, and its bacteriostatic and bactericidal effects are caused by irreversible leakage of intracellular components. At relatively high concentrations, olanexidine aggregates cells by denaturing proteins. This mechanism differs slightly from that of a similar biguanide compound, chlorhexidine. PMID:25987609

  15. Bactericidal Effects and Mechanism of Action of Olanexidine Gluconate, a New Antiseptic.

    Science.gov (United States)

    Hagi, Akifumi; Iwata, Koushi; Nii, Takuya; Nakata, Hikaru; Tsubotani, Yoshie; Inoue, Yasuhide

    2015-08-01

    Olanexidine gluconate [1-(3,4-dichlorobenzyl)-5-octylbiguanide gluconate] (development code OPB-2045G) is a new monobiguanide compound with bactericidal activity. In this study, we assessed its spectrum of bactericidal activity and mechanism of action. The minimal bactericidal concentrations of the compound for 30-, 60-, and 180-s exposures were determined with the microdilution method using a neutralizer against 320 bacterial strains from culture collections and clinical isolates. Based on the results, the estimated bactericidal olanexidine concentrations with 180-s exposures were 869 μg/ml for Gram-positive cocci (155 strains), 109 μg/ml for Gram-positive bacilli (29 strains), and 434 μg/ml for Gram-negative bacteria (136 strains). Olanexidine was active against a wide range of bacteria, especially Gram-positive cocci, including methicillin-resistant Staphylococcus aureus and vancomycin-resistant enterococci, and had a spectrum of bactericidal activity comparable to that of commercial antiseptics, such as chlorhexidine and povidone-iodine. In vitro experiments exploring its mechanism of action indicated that olanexidine (i) interacts with the bacterial surface molecules, such as lipopolysaccharide and lipoteichoic acid, (ii) disrupts the cell membranes of liposomes, which are artificial bacterial membrane models, (iii) enhances the membrane permeability of Escherichia coli, (iv) disrupts the membrane integrity of S. aureus, and (v) denatures proteins at relatively high concentrations (≥160 μg/ml). These results indicate that olanexidine probably binds to the cell membrane, disrupts membrane integrity, and its bacteriostatic and bactericidal effects are caused by irreversible leakage of intracellular components. At relatively high concentrations, olanexidine aggregates cells by denaturing proteins. This mechanism differs slightly from that of a similar biguanide compound, chlorhexidine. Copyright © 2015, American Society for Microbiology. All Rights

  16. Physical Activity and Pattern of Blood Pressure in Postmenopausal ...

    African Journals Online (AJOL)

    Background: Hormonal changes during menopause have been attributed to hypertension-a common public health concern. This study investigated physical activity (PA) and pattern of blood pressure (BP) in postmenopausal women newly diagnosed with hypertension and referred for treatment at the medicine outpatient ...

  17. Physical activity, change in blood pressure and predictors of ...

    African Journals Online (AJOL)

    A South African population which has been historically disadvantaged has been shown to have the highest prevalence of hypertension in the country.9. Studies have previously demonstrated an inverse association between increased physical activity levels and blood pressure in the elderly, particularly in hypertensive.

  18. Prolonged storage of red blood cells affects aminophospholipid translocase activity

    NARCIS (Netherlands)

    Verhoeven, A. J.; Hilarius, P. M.; Dekkers, D. W. C.; Lagerberg, J. W. M.; de Korte, D.

    2006-01-01

    BACKGROUND AND OBJECTIVES: Loss of phospholipid asymmetry in the membrane of red blood cells (RBC) results in exposure of phosphatidylserine (PS) and to subsequent removal from the circulation. In this study, we investigated the effect of long-term storage of RBCs on two activities affecting

  19. Somatotype, blood pressure and physical activity among 10- to 15 ...

    African Journals Online (AJOL)

    Awareness of blood pressure issues in the pediatric population has increased, leading to conceptual changes in the diagnosis and treatment of childhood hypertension. Physical activity may be utilized in the prevention and treatment of an unhealthy body composition due to the increase in resting metabolic rate, and the ...

  20. Adenosine deaminase activities and fasting blood glucose in obesity ...

    African Journals Online (AJOL)

    Background: A complex relationship seems to exist between adenosine deaminase (ADA) and insulin in obesity. Through its effect on adenosine, the enzyme can modulate the action of insulin and affect blood glucose while the administration of insulin is said to decrease the activities of the enzyme. Aim: To investigate the ...

  1. Association of physical activity and physical fitness with blood ...

    African Journals Online (AJOL)

    The current study was conducted to determine how physical activity level and physical fitness affects the blood pressure profile of Maharashtrian adolescents to help in developing preventive strategies for the local population, as ethnic differences exist in the aetiopathogenesis of hypertension. A cross-sectional study was ...

  2. Performance of a coincidence based blood activity monitor

    International Nuclear Information System (INIS)

    Moses, W.W.

    1989-12-01

    A new device has been constructed that measures the positron emitting radio-tracer concentration in arterial blood by extracting blood with a peristaltic pump, then measuring the activity concentration by detecting coincident pairs of 511 keV photons with a pair of heavy inorganic scintillators attached to photomultiplier tubes. The sensitivity of this device is experimentally determined to be 610 counts/second per μCi/ml, and has a paralyzing dead time of 1.2 μs, so is capable of measuring blood activity concentration as high as 1 mCi/ml. Its performance is compared to two other blood monitoring methods: discrete blood samples counted with a well counter and device that uses a plastic scintillator to directly detect positrons. The positron detection efficiency of this device for 18 F is greater than the plastic scintillation counter, and also eliminates the radioisotope dependent correction factors necessary to convert count rate to absolute concentration. Coincident photon detection also has the potential of reducing the background compared to direct positron detection, thereby increasing the minimum detectable isotope concentration. 10 refs., 6 figs

  3. Bactericidal behavior of Cu-containing stainless steel surfaces

    Science.gov (United States)

    Zhang, Xiangyu; Huang, Xiaobo; Ma, Yong; Lin, Naiming; Fan, Ailan; Tang, Bin

    2012-10-01

    Stainless steels are one of the most common materials used in health care environments. However, the lack of antibacterial advantage has limited their use in practical application. In this paper, antibacterial stainless steel surfaces with different Cu contents have been prepared by plasma surface alloying technology (PSAT). The steel surface with Cu content 90 wt.% (Cu-SS) exhibits strong bactericidal activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) within 3 h. Although the Cu-containing surface with Cu content 2.5 wt.% (CuNi-SS) can also kill all tested bacteria, this process needs 12 h. SEM observation of the bacterial morphology and an agarose gel electrophoresis were performed to study the antibacterial mechanism of Cu-containing stainless steel surfaces against E. coli. The results indicated that Cu ions are released when the Cu-containing surfaces are in contact with bacterial and disrupt the cell membranes, killing the bacteria. The toxicity of Cu-alloyed surfaces does not cause damage to the bacterial DNA. These results provide a scientific explanation for the antimicrobial applications of Cu-containing stainless steel. The surfaces with different antibacterial abilities could be used as hygienic surfaces in healthcare-associated settings according to the diverse requirement of bactericidal activities.

  4. Enhancing anaerobic digestion of poultry blood using activated carbon

    Directory of Open Access Journals (Sweden)

    Maria José Cuetos

    2017-05-01

    Full Text Available The potential of using anaerobic digestion for the treatment of poultry blood has been evaluated in batch assays at the laboratory scale and in a mesophilic semi-continuous reactor. The biodegradability test performed on residual poultry blood was carried out in spite of high inhibitory levels of acid intermediaries. The use of activated carbon as a way to prevent inhibitory conditions demonstrated the feasibility of attaining anaerobic digestion under extreme ammonium and acid conditions. Batch assays with higher carbon content presented higher methane production rates, although the difference in the final cumulative biogas production was not as sharp. The digestion of residual blood was also studied under semi-continuous operation using granular and powdered activated carbon. The average specific methane production was 216 ± 12 mL CH4/g VS. This result was obtained in spite of a strong volatile fatty acid (VFA accumulation, reaching values around 6 g/L, along with high ammonium concentrations (in the range of 6–8 g/L. The use of powdered activated carbon resulted in a better assimilation of C3-C5 acid forms, indicating that an enhancement in syntrophic metabolism may have taken place. Thermal analysis and scanning electron microscopy (SEM were applied as analytical tools for measuring the presence of organic material in the final digestate and evidencing modifications on the carbon surface. The addition of activated carbon for the digestion of residual blood highly improved the digestion process. The adsorption capacity of ammonium, the protection this carrier may offer by limiting mass transfer of toxic compounds, and its capacity to act as a conductive material may explain the successful digestion of residual blood as the sole substrate.

  5. Diurnal fluctuation of leukocyte G6PD activity. A possible explanation for the normal neutrophil bactericidal activity and the low incidence of pyogenic infections in patients with severe G6PD deficiency in Israel

    NARCIS (Netherlands)

    Wolach, Baruch; Ashkenazi, Meir; Grossmann, Rami; Gavrieli, Ronit; Friedman, Ziva; Bashan, Nava; Roos, Dirk

    2004-01-01

    Acute hemolytic anemia associated with red blood cell (RBC) glucose-6-phosphate dehydrogenase (G6PD) deficiency is commonly encountered in the Mediterranean basin. Nevertheless, concomitant clinical evidence of white blood cell G6PD deficiency is extremely rare in Israel. This study sought to assess

  6. Total antiradical activity in male castrated piglets blood: reference values

    Directory of Open Access Journals (Sweden)

    Carlo Corino

    2010-01-01

    Full Text Available Blood samples from 146 male castrated piglets in the range of 10-47kg body weight were collected from the same farm and analysed for total antiradical activity in order to determine reference intervals. Data were tested for normality and then submitted to reference limit evaluation. The reference values found in piglets, expressed as half-hemolysis time (59.34 – 93.60 and 43.94 – 66.90 minutes for blood and red blood cell, respectively, are lower than those found in humans; further studies are needed to extend reference values study to female and to animals of different weight classes and different genetic type.

  7. Bactericidal Antibiotics Do Not Appear To Cause Oxidative Stress in Listeria monocytogenes

    DEFF Research Database (Denmark)

    Feld, Louise; Knudsen, Gitte Maegaard; Gram, Lone

    2012-01-01

    Oxidative stress can be an important contributor to the lethal effect of bactericidal antibiotics in some bacteria, such as Escherichia coli and Staphylococcus aureus. Thus, despite the different target-specific actions of bactericidal antibiotics, they have a common mechanism leading to bacterial...... to cause oxidative stress in L. monocytogenes and propose that this is caused by its noncyclic tricarboxylic acid (TCA) pathway. Hence, in this noncyclic metabolism, there is a decoupling between the antibiotic-mediated cellular requirement for NADH and the induction of TCA enzyme activity, which...

  8. Integrated antifouling and bactericidal polymer membranes through bioinspired polydopamine/poly(N-vinyl pyrrolidone) coating

    International Nuclear Information System (INIS)

    Wang, Xianghong; Yuan, Shuaishuai; Shi, Dean; Yang, Yingkui; Jiang, Tao; Yan, Shunjie; Shi, Hengchong; Luan, Shifang; Yin, Jinghua

    2016-01-01

    Graphical abstract: - Highlights: • Antifouling and bactericidal capabilities were facilely integrated into a surface via bioinspired coating. • The modification technique was very facile and universal to different types of substrate materials. • The integrated antifouling and bactericidal surfaces have great potential in wound dressing applications. - Abstract: Polypropylene (PP) non-woven has been widely used as wound dressing; however, the hydrophobic nature of PP can initiate bacterial attachment and subsequent biofilm formation. Herein, we propose a facile approach to functionalize PP non-woven with poly(ethylene glycol) (PEG) and poly(N-vinyl pyrrolidone)-iodine complex (PVP-I). PVP and PEG were successively tethered onto PP non-woven surface via versatile bioinspired dopamine (DA) chemistry, followed by complexing iodine with PVP moieties. It was demonstrated through the field emission scanning electron microscope (SEM) and spread plate method that the as-modified PP non-woven integrated both antifouling property of PEG for suppressing bacterial adhesion, and bactericidal property of PVP-I for killing the few adherent bacteria. Meanwhile, it could greatly resist platelet and red blood cell adhesion. The integrated antifouling and bactericidal PP non-woven surfaces might have great potential in various wound dressing applications.

  9. Bactericidal effects of deep ultraviolet light-emitting diode for solutions during intravenous infusion.

    Science.gov (United States)

    Omotani, Sachiko; Tani, Katsuji; Aoe, Mai; Esaki, Seiji; Nagai, Katsuhito; Hatsuda, Yasutoshi; Mukai, Junji; Teramachi, Hitomi; Myotoku, Michiaki

    2018-01-01

    Background: Ultraviolet irradiation is effectively used as a disinfection method for inactivating microorganisms. Methods: We investigated the bactericidal effects by irradiation with a deep-ultraviolet light-emitting diode (DUV-LED) on the causative microorganisms of catheter related blood stream infection contaminating the solution for intravenous infusion. For irradiation, prototype modules for water disinfection with a DUV-LED were used. Experiments were conducted on five kinds of microorganisms. We examined the dependence of bactericidal action on eleven solutions. Administration sets were carried out three types. Results: When the administration set JY-PB343L containing the infusion tube made of polybutadiene was used, the bactericidal action of the DUV-LED against all tested microorganisms in the physiological saline solutions was considered to be effective. We confirmed that the number of viable bacteria decreased in 5% glucose solution and electrolyte infusions with DUV-LED irradiation. Conclusions: These results indicate that the DUV-LED irradiation has bactericidal effects in glucose infusion and electrolyte infusions by irradiating via a plasticizer-free polybutadiene administration set. We consider DUV-LED irradiation to be clinically applicable.

  10. Integrated antifouling and bactericidal polymer membranes through bioinspired polydopamine/poly(N-vinyl pyrrolidone) coating

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xianghong [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Faculty of Materials Science and Engineering, Hubei University, Wuhan 430062 (China); Yuan, Shuaishuai [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Shi, Dean, E-mail: deanshi2012@yahoo.com [Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Faculty of Materials Science and Engineering, Hubei University, Wuhan 430062 (China); Yang, Yingkui; Jiang, Tao [Ministry of Education Key Laboratory for the Green Preparation and Application of Functional Materials, Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Faculty of Materials Science and Engineering, Hubei University, Wuhan 430062 (China); Yan, Shunjie; Shi, Hengchong [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Luan, Shifang, E-mail: sfluan@ciac.ac.cn [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China); Yin, Jinghua [State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

    2016-07-01

    Graphical abstract: - Highlights: • Antifouling and bactericidal capabilities were facilely integrated into a surface via bioinspired coating. • The modification technique was very facile and universal to different types of substrate materials. • The integrated antifouling and bactericidal surfaces have great potential in wound dressing applications. - Abstract: Polypropylene (PP) non-woven has been widely used as wound dressing; however, the hydrophobic nature of PP can initiate bacterial attachment and subsequent biofilm formation. Herein, we propose a facile approach to functionalize PP non-woven with poly(ethylene glycol) (PEG) and poly(N-vinyl pyrrolidone)-iodine complex (PVP-I). PVP and PEG were successively tethered onto PP non-woven surface via versatile bioinspired dopamine (DA) chemistry, followed by complexing iodine with PVP moieties. It was demonstrated through the field emission scanning electron microscope (SEM) and spread plate method that the as-modified PP non-woven integrated both antifouling property of PEG for suppressing bacterial adhesion, and bactericidal property of PVP-I for killing the few adherent bacteria. Meanwhile, it could greatly resist platelet and red blood cell adhesion. The integrated antifouling and bactericidal PP non-woven surfaces might have great potential in various wound dressing applications.

  11. Bactericidal and Bioactive Dental Composites.

    Science.gov (United States)

    Chatzistavrou, Xanthippi; Lefkelidou, Anna; Papadopoulou, Lambrini; Pavlidou, Eleni; Paraskevopoulos, Konstantinos M; Fenno, J Christopher; Flannagan, Susan; González-Cabezas, Carlos; Kotsanos, Nikos; Papagerakis, Petros

    2018-01-01

    Aim: Antimicrobial and bioactive restorative materials are needed to develop a bacteria free environment and tight bond with the surrounding tissue, preventing the spread of secondary caries and thus extending the lifetime of dental restorations. The characteristic properties of new dental bioactive and antibacterial composites are presented in this work. The new composites have been microstructurally characterized and both long and short term properties have been studied. Methods: The Ag-doped sol-gel derived bioactive glass (Ag-BG) was incorporated into resin composite in concentrations 5, 10, and 15 wt.%, to fabricate new Ag-doped bioactive and antibacterial dental composites (Ag-BGCOMP). The microstructural properties and elemental analysis of the developed Ag-BGCOMP was observed. The total bond strength (TBS) was measured immediately and after long term of immersion in medium using microtensile testing. The capability of Ag-BGCOMPs to form apatite layer on their surface after immersion in Simulated Body Fluid (SBF) as well as the bacteria growth inhibition in a biofilm formed by Streptococcus mutans ( S. mutans ) were evaluated. Results: Homogeneous distribution of Ag-BG particles into the resin composite was observed microstructurally for all Ag-BGCOMPs. The TBS measurements showed non-statistically significant difference between control samples (Ag-BG 0 wt.%) and Ag-BGCOMP specimens. Moreover, the total bond strength between the surrounding tooth tissue and the material of restoration does not present any statistically significant change for all the cases even after 3 months of immersion in the medium. The bioactivity of the Ag-BGCOMPs was also shown by the formation of a calcium-phosphate layer on the surface of the specimens after immersion in SBF. Antibacterial activity was observed for all Ag-BGCOMPs, statistically significant differences were observed between control samples and Ag-BGCOMPs. Accordingly, the number of dead bacteria in the biofilm found

  12. Bactericidal effects of deep ultraviolet light-emitting diode for solutions during intravenous infusion

    OpenAIRE

    Omotani, Sachiko; Tani, Katsuji; Aoe, Mai; Esaki, Seiji; Nagai, Katsuhito; Hatsuda, Yasutoshi; Mukai, Junji; Teramachi, Hitomi; Myotoku, Michiaki

    2018-01-01

    Background: Ultraviolet irradiation is effectively used as a disinfection method for inactivating microorganisms. Methods: We investigated the bactericidal effects by irradiation with a deep-ultraviolet light-emitting diode (DUV-LED) on the causative microorganisms of catheter related blood stream infection contaminating the solution for intravenous infusion. For irradiation, prototype modules for water disinfection with a DUV-LED were used. Experiments were conducted on five kinds of microor...

  13. Bactericidal antibody response against P6, protein D, and OMP26 of nontypeable Haemophilus influenzae after acute otitis media in otitis-prone children.

    Science.gov (United States)

    Khan, M Nadeem; Kaur, Ravinder; Pichichero, Michael E

    2012-08-01

    The bactericidal antibody response to three nontypeable Haemophilus influenzae (NTHi) outer membrane proteins (D, P6, and OMP26) was studied in 24 otitis-prone children (aged 7-28 months) after an acute otitis media (AOM) caused by NTHi. The study was carried out to understand the contribution of antigen-specific bactericidal antibody responses in the class of children who are most vulnerable to recurrent otitis media infections. Levels of protein D (P = 0.005) and P6 (P = 0.026) but not OMP26 antibodies were higher in bactericidal sera compared with nonbactericidal sera. For five (24%) and 16 (76%) of 21 bactericidal sera tested, removal of anti-protein D and P6 antibody, respectively, resulted in a two- to fourfold drop in bactericidal antibody. Antibodies to OMP26 did not make any contribution to the overall bactericidal activity in any serum samples. Eleven of 21 sera (52%) had bactericidal activity against a heterologous NTHi (86-028 NP) strain but the titers were significantly lower (P bactericidal antibody in children who are otitis prone as a possible correlate of protection. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  14. [Activity of blood serum lactate dehydrogenase in diabetes mellitus].

    Science.gov (United States)

    Vizir, O O

    1977-01-01

    The activity of lactic dehydrogenase of the blood serum was studied under clinical conditions in 120 patients suffering from diabetes mellitus. Electrophoretic separation of plasma enzymes was used for this purpose. The shifts in the LDH activity proved to be characteristic of all the degrees of diabetes severity, and were expressed in a significant elevation of total LDH, LDH4,5 activity and a decrease of LDH1,2 activity in comparison with healthy individuals. No change of LDH3 activity was noted in mild forms of diabetes. But in severe form the isoenzymatic spectrum was mostly changed on account of LDH3 hyperfermentemia. In mild form of diabetes it approached control values.

  15. Physical activity and blood pressure. A cross-sectional review

    OpenAIRE

    Støyten, Martin

    2017-01-01

    Background: Hypertension is known as a major risk factor for cardiovascular disease, and the world-wide prevalence of hypertension is expected to rise to 30 % by the end of 2025. Physical activity has been shown to be a major part of the conservative treatment of hypertension, although the nature of the dose-response relationship is not known. The purpose of this study was to examine the associations between physical activity and blood pressure in the sixth survey of the Tromsø Study. Meth...

  16. Effect of Heptral on Blood Coagulant Activity in Pancreonecrosis

    Directory of Open Access Journals (Sweden)

    M. S. Sukach

    2011-01-01

    Full Text Available Objective: to attempt to reduce the hemostatic, detoxifying, and antioxidant dysfunctions of the liver in experimental pancreonecrosis and the degree of pancreatogenic endotoxemia, by using the hepatoprotector heptral. Materials and methods. Experiments were carried out on 142 outbred male rats divided into 3 groups: 1 control (n=20; 2 study (n=69; 3 comparison (n=53. Pancreonecrosis was simulated in the study and comparison groups. In Stage 1, coagulation hemostatic parameters were studied and the levels of low and medium molecular weight substances and the rate of free radical oxidation processes were determined. In Stage 2, five minutes after stimulation of pancreonecrosis, heptral was given in a dose of 11.4 mg/kg to the comparison animals, by studying the same parameters as in the study and control groups. The results were processed using the nonparametric statistical methods. Results. It has been found that hepatic detoxifying and antioxidant functions are impaired and free radical oxidation processes activated within 2 days after simulation of pancreonecrosis. Blood coagulation activity is considerably higher due to activated coagulation factors. Heptral increases the capacity of the liver to synthesize blood coagulation factors, which proves improvement of some of the study parameters of the hemostatic system. Furthermore, its administration preserves the antitoxic function of hepatocytes, as shown by the decreased concentrations of low and median molecular weight substances in plasma and red blood cells. At the same time, there is an increase in antioxidant system activity detectable by chemiluminescence which also testifies that hepatic functional and metabolic impairments are ameliorated. Key words: pancreonecrosis, liver, endotoxemia, hemo-stasis, free radical oxidation, heptral.

  17. Development and use of a serum bactericidal assay using pooled human complement to assess responses to a meningococcal group A conjugate vaccine in African toddlers.

    Science.gov (United States)

    Bash, Margaret C; Lynn, Freyja; Mocca, Brian; Borrow, Ray; Findlow, Helen; Hassan-King, Musa; Preziosi, Marie-Pierre; Idoko, Olubukola; Sow, Samba; Kulkarni, Prasad; Laforce, F Marc

    2014-05-01

    A meningococcal group A polysaccharide (PS) conjugate vaccine (PsA-TT) has been developed for African countries affected by epidemic meningitis caused by Neisseria meningitidis. Complement-mediated serum bactericidal antibody (SBA) assays are used to assess protective immune responses to meningococcal vaccination. Human complement (hC') was used in early studies demonstrating antibody-mediated protection against disease, but it is difficult to obtain and standardize. We developed and evaluated a method for sourcing hC' and then used the SBA assay with hC' (hSBA) to measure bactericidal responses to PsA-TT vaccination in 12- to 23-month-old African children. Sera with active complement from 100 unvaccinated blood donors were tested for intrinsic bactericidal activity, SBA titer using rabbit complement (rSBA), and anti-group A PS antibody concentration. Performance criteria and pooling strategies were examined and then verified by comparisons of three independently prepared hC' lots in two laboratories. hSBA titers of clinical trial sera were then determined using this complement sourcing method. Two different functional antibody tests were necessary for screening hC'. hSBA titers determined using three independent lots of pooled hC' were within expected assay variation among lots and between laboratories. In African toddlers, PsA-TT elicited higher hSBA titers than meningococcal polysaccharide or Hib vaccines. PsA-TT immunization or PS challenge of PsA-TT-primed subjects resulted in vigorous hSBA memory responses, and titers persisted in boosted groups for over a year. Quantifying SBA using pooled hC' is feasible and showed that PsA-TT was highly immunogenic in African toddlers.

  18. Correlations between phytohemagglutinin response and leukocyte profile, and bactericidal capacity in a wild rodent.

    Science.gov (United States)

    Zhang, Zhiqiang; Zhao, Zhijun

    2015-05-01

    Phytohemagglutinin (PHA)-induced swelling is widely used to investigate cell-mediated and innate immunity across different vertebrate taxa. However, its physiological mechanism is still an open question due to the complexity of the involved immune components. In the present study, we measured the synchronous variations of PHA response, the proportion of different subtypes of leukocytes, as well as serum bactericidal capacity in circulation blood at 6, 12 and 24 h after PHA versus PBS injection in striped hamster, Cricetulus barabensis. First, the results showed that PHA responses reached a peak at 6 h postinjection, then sharply declined at 12 h and 24 h postinjection. Serum bactericidal capacity was higher at 6 h and 12 h than at 24 h. The proportion of different subtypes of leukocytes, as well as the ratio of neutrophils to lymphocytes did not display significant changes across different time points. Second, PHA response was positively correlated with the proportion of neutrophils and serum bactericidal capacity. The proportion of monocytes was negatively correlated with that of eosinophils and neutrophils. The proportion of basophils was negatively correlated with that of lymphocytes. Our results indicate that earlier enhanced PHA response is important for the striped hamster to cope with changing environmental conditions due to its small body mass, and the increased components of innate immunity in circulation blood may contribute to the enhancement of PHA swelling response. © 2015 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

  19. Selenium-mediated protection in reversing the sensitivity of bacterium to the bactericidal antibiotics.

    Science.gov (United States)

    Li, Zhonglei; Tan, Jun; Shao, Lei; Dong, Xiaojing; Ye, Richard D; Chen, Daijie

    2017-05-01

    Inducing production of damaging reactive oxygen species (ROS) is an important criterion to distinguish the bactericidal antibiotics from bacteriostatic antibiotics. Selenoenzymes were generally recognized to be a powerful antioxidant capable of scavenging free radicals, protecting the cells from the harmful effects of ROS. Therefore, the present study was carried out to investigate the selenium (Se)-mediated protection in reversing antibiotic sensitivity and the role of selenoenzymes in alleviating the negative effects of oxidative stress. The cellular antioxidant activity of Se-enriched bacteria was analyzed, as well as intracellular ROS production and elimination when Se-enriched bacteria in the presence of various antibiotics. Compared to complete inhibition of the parental strain by bactericidal antibiotics, it only exhibited slight and reversible inhibition of Se-enriched Escherichia coli ATCC25922 and Staphylococcus aureus ATCC25923 at the same conditions, which indicated that intracellular selenium provided substantial protection against antibiotics. ROS generation caused by bactericidal antibiotics was confirmed by fluorescence spectrophotometry using 2', 7'-dichloro- uorescein diacetate (DCFH-DA) as substrate. The time course experiments of pretreatment with selenium showed significant decrease of ROS level at 2h. In summary, the present study provides experimental evidence supporting selenoenzymes has good scavenging effect to ROS and can protect bacteria from oxidative stress injury induced by bactericidal antibiotics. Copyright © 2017 Elsevier GmbH. All rights reserved.

  20. The bactericidal effect of an ionizer under low concentration of ozone.

    Science.gov (United States)

    Park, Jin-Soo; Sung, Bong-Jo; Yoon, Kyung-Soo; Jeong, Choon-Soo

    2016-07-30

    Several mechanisms have been suggested for the bactericidal action of ionizers including electrical phenomena, effects of negative and positive ions and electrostatic repulsion. Negative and positive ions have indeed been shown to have bactericidal effects. In addition, since ozone is generated along with ions, these may contribute to the bacterial killing. In this study, we used a newly developed ionizer, which generates a relatively low concentration of ozone, to determine whether its effect on bacterial cells were due to ions or ozone, and, if ions, how the ions exerted their effects. The effect of ions on bacterial killing was compared with that of the ozone produced using an ion trap to remove the ions. The ionizer had the ability to kill the bacteria, and ion capture dramatically reduced its bactericidal effect, indicating that the ozone generated had little or no bactericidal effect under these conditions, and the ions produced were responsible for almost all the bacterial killing. Operation of the ionizer increased the level of 8-oxo-dG, a marker of oxidative DNA damage, and decreased aconitase activity, which is known to be sensitive to ROS. The ionizer further affected the adenylate energy charge of bacterial cells. Removal of the ions with the ion trap greatly reduced all these effects. These results indicate that negative and positive ions generated by the ionizer are responsible for inducing oxidative stress and so reducing bacterial survival.

  1. Influence of nanoscale topology on bactericidal efficiency of black silicon surfaces

    Science.gov (United States)

    Linklater, Denver P.; Khuong Duy Nguyen, Huu; Bhadra, Chris M.; Juodkazis, Saulius; Ivanova, Elena P.

    2017-06-01

    The nanostructuring of materials to create bactericidal and antibiofouling surfaces presents an exciting alternative to common methods of preventing bacterial adhesion. The fabrication of synthetic bactericidal surfaces has been inspired by the anti-wetting and anti-biofouling properties of insect wings, and other topologies found in nature. Black silicon is one such synthetic surfaces which has established bactericidal properties. In this study we show that time-dependent plasma etching of silicon wafers using 15, 30, and 45 min etching intervals, is able to produce different surface geometries with linearly increasing heights of approximately 280, 430, and 610 nm, respectively. After incubation on these surfaces with Gram-positive Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa bacterial cells it was established that smaller, more densely packed pillars exhibited the greatest bactericidal activity with 85% and 89% inactivation of bacterial cells, respectively. The decrease in the pillar heights, pillar cap diameter and inter-pillar spacing corresponded to a subsequent decrease in the number of attached cells for both bacterial species.

  2. Bactericidal effects of 310 nm ultraviolet light-emitting diode irradiation on oral bacteria.

    Science.gov (United States)

    Takada, Ayuko; Matsushita, Kenji; Horioka, Satoru; Furuichi, Yasushi; Sumi, Yasunori

    2017-06-06

    Ultraviolet (UV) light is used for phototherapy in dermatology, and UVB light (around 310 nm) is effective for treatment of psoriasis and atopic dermatitis. In addition, it is known that UVC light (around 265 nm) has a bactericidal effect, but little is known about the bactericidal effect of UVB light. In this study, we examined the bactericidal effects of UVB-light emitting diode (LED) irradiation on oral bacteria to explore the possibility of using a 310 nm UVB-LED irradiation device for treatment of oral infectious diseases. We prepared a UVB (310 nm) LED device for intraoral use to examine bactericidal effects on Streptococcus mutans, Streptococcus sauguinis, Porphyromonas gingivalis, and Fusobacterium nucleatum and also to examine the cytotoxicity to a human oral epithelial cell line (Ca9-22). We also examined the production of nitric oxide and hydrogen peroxide from Ca9-22 cells after irradiation with UVB-LED light. Irradiation with the 310 nm UVB-LED at 105 mJ/cm 2 showed 30-50% bactericidal activity to oral bacteria, though 17.1 mJ/cm 2 irradiation with the 265 nm UVC-LED completely killed the bacteria. Ca9-22 cells were strongly injured by irradiation with the 265 nm UVC-LED but were not harmed by irradiation with the 310 nm UVB-LED. Nitric oxide and hydrogen peroxide were produced by Ca9-22 cells with irradiation using the 310 nm UVB-LED. P. gingivalis was killed by applying small amounts of those reactive oxygen species (ROS) in culture, but other bacteria showed low sensitivity to the ROS. Narrowband UVB-LED irradiation exhibited a weak bactericidal effect on oral bacteria but showed low toxicity to gingival epithelial cells. Its irradiation also induces the production of ROS from oral epithelial cells and may enhance bactericidal activity to specific periodontopathic bacteria. It may be useful as a new adjunctive therapy for periodontitis.

  3. 21 CFR 864.7140 - Activated whole blood clotting time tests.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Activated whole blood clotting time tests. 864....7140 Activated whole blood clotting time tests. (a) Identification. An activated whole blood clotting time tests is a device, used to monitor heparin therapy for the treatment of venous thrombosis or...

  4. Physical Activity, Obesity Status, and Blood Pressure in Preschool Children.

    Science.gov (United States)

    Vale, Susana; Trost, Stewart G; Rêgo, Carla; Abreu, Sandra; Mota, Jorge

    2015-07-01

    To examine the combined effects of physical activity and weight status on blood pressure (BP) in preschool-aged children. The sample included 733 preschool-aged children (49% female). Physical activity was objectively assessed on 7 consecutive days by accelerometry. Children were categorized as sufficiently active if they met the recommendation of at least 60 minutes daily of moderate-to-vigorous physical activity (MVPA). Body mass index was used to categorize children as nonoverweight or overweight/obese, according to the International Obesity Task Force benchmarks. BP was measured using an automated BP monitor and categorized as elevated or normal using BP percentile-based cut-points for age, sex, and height. The prevalence of elevated systolic BP (SBP) and diastolic BP was 7.7% and 3.0%, respectively. The prevalence of overweight/obese was 32%, and about 15% of children did not accomplish the recommended 60 minutes of daily MVPA. After controlling for age and sex, overweight/obese children who did not meet the daily MVPA recommendation were 3 times more likely (OR 3.8; CI 1.6-8.6) to have elevated SBP than nonoverweight children who met the daily MVPA recommendation. Overweight or obese preschool-aged children with insufficient levels of MVPA are at significantly greater risk for elevated SBP than their nonoverweight and sufficiently active counterparts. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Adhesion molecules levels in blood correlate with MRI activity and clinical activity in multiple sclerosis

    International Nuclear Information System (INIS)

    Millers, A.; Enina, G.; Platkajis, A.; Metra, M.; Kukaine, R.

    2002-01-01

    Research into pathogenesis of multiple sclerosis (MS) has prompted efforts to identify immunological markers associated with disease activity. Adhesion molecules ICAM-1 and VCAM-1 are associated with inflammatory mediated blood-brain barrier (BBB) dysfunction. In this study investigates the correlation between blood level of circulating ICAM-1 and VCAM-1 and magnetic resonance imaging (MRI) activity in different clinical phases of patients with MS. We show that RRMS and SPMS patients in clinically active phase with Gd-enhancing lesions in CNS had higher blood levels of cICAM-1 and cVCAM-1 compared these parameters levers of RRMS patients in remission stage. These results suggest that cICAM-1 and cVCAM-1 is a sensitive indicator of disease activity associated with BBB inflammatory dysfunction. Elevated blood level of cICAM-1 more strongly correlated with clinical activity and BBB damage, than cVCAM-1 and that could be used as biological marker of disease activity. Circulating VCAM-1 as an early indicator of BBB disturbance, may also serve as marker of beneficial activity in relapses phase of MS course. (authors)

  6. Effect of exercise on erythrocyte count and blood activity concentration after technetium-99m in vivo red blood cell labeling

    International Nuclear Information System (INIS)

    Konstom, M.A.; Tu'meh, S.; Wynne, J.; Beck, J.R.; Kozlowski, J.; Holman, B.L.

    1982-01-01

    The effects of exercise on blood radiotracer concentration after technetium-99m in vivo red blood cell labeling was studied. After red blood cell labeling, 13 subjects underwent maximal supine bicycle exercise. Radioactivity, analyzed with a well counter, was measured in heparinized venous blood samples drawn at rest and during peak exercise. Changes in activity were compared with changes in erythrocyte count. Activity and erythrocyte counts increased in erythrocyte count (r=0.78), but did not correlate with either duration of exercise or maximal heart rate. Twenty minutes after termination of exercise, activity and erythrocyte count had decreased from peak exercise values but remained higher than preexercise values. In nine nonexercised control subjects, samples drawn 20 minutes apart showed no change in activity or in erythrocyte count. It was concluded that exercise increases blood activity, primarily because of an increase in erythrocyte count. During radionuclide ventriculography, blood activity must be measured before and after any intervention, particularly exercise, before a change in left ventricular activity can be attributed to a change in left ventricular volume

  7. Vitamin E nanoemulsion activity on stored red blood cells.

    Science.gov (United States)

    Silva, C A L; Azevedo Filho, C A; Pereira, G; Silva, D C N; Castro, M C A B; Almeida, A F; Lucena, S C A; Santos, B S; Barjas-Castro, M L; Fontes, A

    2017-06-01

    Stored red blood cells (RBCs) undergo numerous changes that have been termed RBC storage lesion, which can be related to oxidative damage. Vitamin E is an important antioxidant, acting on cell lipids. Thus, this study aimed to investigate vitamin E activity on stored RBCs. We prepared a vitamin E nanoemulsion that was added to RBC units and stored at 4 °C. Controls, without vitamin E, were kept under the same conditions. Reactive oxygen species (ROS) production was monitored for up to 35 days of storage. RBC elasticity was also evaluated using an optical tweezer system. Vitamin E-treated samples presented a significant decrease in ROS production. Additionally, the elastic constant for vitamin E-treated RBCs did not differ from the control. Vitamin E decreased the amount of ROS in stored RBCs. Because vitamin E acts on lipid oxidation, results suggest that protein oxidation should also be considered a key factor for erythrocyte elastic properties. Thus, further studies combining vitamin E with protein antioxidants deserve attention, aiming to better preserve overall stored RBC properties. © 2017 British Blood Transfusion Society.

  8. Effect of Physical Activity on Blood Pressure Distribution among School Children

    OpenAIRE

    Anisa M. Durrani; Waseem Fatima

    2015-01-01

    The present study analyzed the relationship between physical activity and blood pressure in 701 school children aged 12–16 years (girls = 338, boys = 363). During the baseline examination, systolic blood pressure (SBP) and diastolic blood pressure (DBP), height, weight, and 24-hour recall of the working day activity with duration were recorded. Total activity score and type of activity were calculated by weighing the activity level. Mean, standard deviation, and correlation coefficient were c...

  9. Highly Bactericidal Polyurethane Effective Against Both Normal and Drug-Resistant Bacteria: Potential Use as an Air Filter Coating.

    Science.gov (United States)

    Taylor, Matthew; McCollister, Bruce; Park, Daewon

    2016-03-01

    The battle against the prevalence of hospital-acquired infections has underscored the importance of identifying and maintaining the cleanliness of possible infection transmission sources in the patient's environment. One of the most crucial lines of defense for mitigating the spread of pathogens in a healthcare facility is the removal of microorganisms from the environment by air filtration systems. After removing the pathogenic microorganisms, the filters used in these systems can serve as reservoirs for the pathogens and pose a risk for secondary infection. This threat, combined with the ever-growing prevalence of drug-resistant bacterial strains, substantiates the need for an effective bactericidal air filter. To this end, a broad-spectrum bactericidal polyurethane incorporating immobilized quaternary ammonium groups was developed for use as an air filter coating. In this study, the bactericidal activity of the polymer coating on high-efficiency particulate air (HEPA) filter samples was quantified against eight bacterial strains commonly responsible for nosocomial infection-including drug-resistant strains, and confirmed when applied as a filter coating in conditions mimicking those of its intended application. The coated HEPA filter samples exhibited high bactericidal activity against all eight strains, and the polyurethane was concluded to be an effective coating in rendering HEPA filters bactericidal.

  10. Bactericidal effect of a 405-nm diode laser on Porphyromonas gingivalis

    International Nuclear Information System (INIS)

    Kotoku, Y; Kato, J; Akashi, G; Hirai, Y; Ishihara, K

    2009-01-01

    The study was conducted to determine the effect of 405-nm diode laser irradiation on periodontopathic bacteria such as Porphyromonas gingivalis in vitro. A diluted suspension of P. gingivalis was irradiated directly with a 405-nm diode laser under conditions of 100 mW-10 sec, 100 mW-20 sec, 200 mW-5 sec, 200 mW-10 sec, 200 mW-20 sec, 400 mW-5 sec, 400 mW-10 sec, and 400 mW-20 sec. The energy density ranged from 2.0 to 16.0 J/cm 2 . The irradiated bacterial suspension was spread on a blood agar plate and growth of the colonies was examined after an anaerobic culture for 7 days. Bacterial growth was inhibited under all irradiation conditions, but the bactericidal effect of the 405-nm diode laser depended on the energy density. More than 97% of bacterial growth was inhibited with irradiation at an energy density > 4.0 J/cm 2 . The mechanism of the bactericidal effect is photochemical, rather than photothermal. These findings suggest that a 405-nm diode laser has a high bactericidal effect on P. gingivalis

  11. Bactericidal effect of a 405-nm diode laser on Porphyromonas gingivalis

    Science.gov (United States)

    Kotoku, Y.; Kato, J.; Akashi, G.; Hirai, Y.; Ishihara, K.

    2009-05-01

    The study was conducted to determine the effect of 405-nm diode laser irradiation on periodontopathic bacteria such as Porphyromonas gingivalis in vitro. A diluted suspension of P. gingivalis was irradiated directly with a 405-nm diode laser under conditions of 100 mW-10 sec, 100 mW-20 sec, 200 mW-5 sec, 200 mW-10 sec, 200 mW-20 sec, 400 mW-5 sec, 400 mW-10 sec, and 400 mW-20 sec. The energy density ranged from 2.0 to 16.0 J/cm2. The irradiated bacterial suspension was spread on a blood agar plate and growth of the colonies was examined after an anaerobic culture for 7 days. Bacterial growth was inhibited under all irradiation conditions, but the bactericidal effect of the 405-nm diode laser depended on the energy density. More than 97% of bacterial growth was inhibited with irradiation at an energy density > 4.0 J/cm2. The mechanism of the bactericidal effect is photochemical, rather than photothermal. These findings suggest that a 405-nm diode laser has a high bactericidal effect on P. gingivalis.

  12. Radionuclide assay of membrane Na+, K+-ATPase activity of peserved red blood cells

    International Nuclear Information System (INIS)

    Trusov, V.V.; Zelenin, A.A.; Marizin, S.A.

    1986-01-01

    The radionuclide tests were used to investigate the influence of varying blood preservatives on erythrocylic membrane Na + , K + -ATPase activity in samples of whole blood and packed red blood cells from normal donors prepared by standard methods. The tests were performed before and after seven days of preservation under standard conditions. It was found that blood preservations lowered membrane Na + , K + -ATPase activity: its minimum reduction was recorded with citroglucopnosphate, while glugicir induced a significant drop in Na + , K + -ATPase activity of preserved red blood cells regardless of the type of the blood transfusion solution. The assay of membrane Na + , K + -ATPase activity of preserved red blood cells with the use of 86 Rb could be recommended as an evaluation test for preserved blood and its components

  13. The bactericidal effect of a Genius Nd: YAG laser

    NARCIS (Netherlands)

    Kranendonk, A.A.; van der Reijden, W.A.; van Winkelhoff, A.J.; van der Weijden, G.A.

    2010-01-01

    Purpose: To evaluate the ‘in vitro’ bactericidal effect of the Nd:YAG laser (Genius, MØlsgaard Dental, Copenhagen, Denmark) on six periodontal pathogens. Methods: Suspensions of six different periodontal pathogens (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella

  14. The bactericidal effect of a Genius (R) Nd : YAG laser

    NARCIS (Netherlands)

    Kranendonk, A.A.; Reijden, W.A. van der; Winkelhoff, A.J. van; Weijden, G.A. van der

    PURPOSE: To evaluate the 'in vitro' bactericidal effect of the Nd:YAG laser (Genius, MØlsgaard Dental, Copenhagen, Denmark) on six periodontal pathogens. METHODS: Suspensions of six different periodontal pathogens (Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Prevotella

  15. Association of physical activity with blood pressure and blood glucose among Malaysian adults: a population-based study.

    Science.gov (United States)

    Teh, Chien Huey; Chan, Ying Ying; Lim, Kuang Hock; Kee, Chee Cheong; Lim, Kuang Kuay; Yeo, Pei Sien; Azahadi, Omar; Fadhli, Yusoff; Tahir, Aris; Lee, Han Lim; Nazni, Wasi Ahmad

    2015-12-03

    The health-enhancing benefits of physical activity (PA) on hypertension and diabetes have been well documented for decades. This study aimed to determine the association of PA with systolic and diastolic blood pressure as well as blood glucose in the Malaysian adult population. Data were extracted from the 2011 National Health and Morbidity Survey (NHMS), a nationally representative, cross-sectional study. A two-stage stratified sampling method was used to select a representative sample of 18,231 Malaysian adults aged 18 years and above. The PA levels of the respondents were categorised as low, moderate or high according to the International Physical Activity Questionnaire (IPAQ)-short form. Blood pressure and fasting blood glucose levels were measured using a digital blood pressure-measuring device and finger-prick test, respectively. Systolic blood pressure (SBP) level was positively associated with PA level (p = 0.02) whilst no significant association was noted between PA level and diastolic blood pressure (DBP). In contrast, respondents with low (adjusted coefficient = 0.17) or moderate (adjusted coefficient = 0.03) level of PA had significantly higher blood glucose level as compared to those who were highly active (p = 0.04). A significant negative association was observed between PA level and blood glucose only. Future studies should employ an objective measurement in estimating PA level in order to elucidate the actual relationship between PA, hypertension and diabetes for the development of effective interventions to combat the increasing burden of premature-mortality and cardiovascular disease-related morbidity in Malaysia.

  16. Green-Tea and Epigallocatechin-3-Gallate are Bactericidal against Bacillus anthracis

    Science.gov (United States)

    2017-06-13

    1849-55. 280 8. Toda M, Okubo S, Hiyoshi R, Shimamura T. 1989. The Bactericidal activity of Tea and Coffee. 281 Letters in Applied Microbiology 8...cup of tea is the answer to everything - including the threat of 329 bioterrorism. Microbiologist (Magazine of the Society for Applied Microbiology ...of the Anthrax Letters , 58 has garnered the interest of the biomedical community and the public to improve current 59 prevention and therapeutic

  17. Blood

    Science.gov (United States)

    ... production of red blood cells, including: Iron deficiency anemia. Iron deficiency anemia is the most common type of anemia and ... inflammatory bowel disease are especially likely to have iron deficiency anemia. Anemia due to chronic disease. People with chronic ...

  18. Association of physical activity with blood pressure and blood glucose among Malaysian adults: a population-based study

    OpenAIRE

    Teh, Chien Huey; Chan, Ying Ying; Lim, Kuang Hock; Kee, Chee Cheong; Lim, Kuang Kuay; Yeo, Pei Sien; Azahadi, Omar; Fadhli, Yusoff; Tahir, Aris; Lee, Han Lim; Nazni, Wasi Ahmad

    2015-01-01

    Background The health-enhancing benefits of physical activity (PA) on hypertension and diabetes have been well documented for decades. This study aimed to determine the association of PA with systolic and diastolic blood pressure as well as blood glucose in the Malaysian adult population. Methods Data were extracted from the 2011 National Health and Morbidity Survey (NHMS), a nationally representative, cross-sectional study. A two-stage stratified sampling method was used to select a represen...

  19. Evaluation of bactericidal effect of three antiseptics on bacteria isolated from wounds.

    Science.gov (United States)

    Kumara, D U A; Fernando, S S N; Kottahachchi, J; Dissanayake, D M B T; Athukorala, G I D D A D; Chandrasiri, N S; Damayanthi, K W N; Hemarathne, M H S L; Pathirana, A A

    2015-01-01

    at the lowest concentration compared to other two acids. Despite promising bactericidal effects, further studies warrant, as ongoing debates on toxicity of acids on tissue epithelialisation. Application of antiseptics for a shorter duration could overcome this problem without losing bactericidal activity. The authors have no conflict of interest and no funding was received for this study.

  20. Reinforcement of the bactericidal effect of ciprofloxacin on Pseudomonas aeruginosa biofilm by hyperbaric oxygen treatment

    DEFF Research Database (Denmark)

    Kolpen, Mette; Mousavi, Nabi; Sams, Thomas

    2016-01-01

    mechanisms affecting antibiotic effectiveness on biofilms remain unclear, accumulating evidence suggests that the efficacy of several bactericidal antibiotics such as ciprofloxacin is enhanced by stimulation of the aerobic respiration of pathogens, and that lack of O2 increases their tolerance. Reoxygenation...... of O2-depleted biofilms may thus improve susceptibility to ciprofloxacin possibly by restoring aerobic respiration. We tested such a strategy using reoxygenation of O2-depleted P. aeruginosa strain PAO1 agarose-embedded biofilms by hyperbaric oxygen treatment (HBOT) (100% O2, 2.8bar), enhancing...... the diffusive supply for aerobic respiration during ciprofloxacin treatment. This proof-of-principle study demonstrates that biofilm reoxygenation by HBOT can significantly enhance the bactericidal activity of ciprofloxacin on P. aeruginosa. Combining ciprofloxacin treatment with HBOT thus clearly has potential...

  1. Physical activity, body mass index and blood pressure in primary ...

    African Journals Online (AJOL)

    Working Group on high blood pressure in children and adolescents: Fourth report on the diagnosis, evaluation and treatment of high blood pressure in children and ad- olescents. Paediatrics 2004; 114: 555 – 566. 21. Owa JA, Adejuyigbe O. Fat mass, fat mass percentage, body mass index and upper mid arm circumference ...

  2. ABO/Rh Blood-Typing Model: A Problem-Solving Activity

    Science.gov (United States)

    Wake, Carol

    2005-01-01

    An ARO/Rh Blood-Typing kit useful for students to visualize blood-typing activities and practice problem-solving skills with transfusion reactions is presented. The model also enables students to identify relationships between A, B, and Rh antigens and antibodies in blood and to understand molecular mechanisms involved in transfusion agglutination…

  3. Temperature-Responsive Hierarchical Polymer Brushes Switching from Bactericidal to Cell Repellency.

    Science.gov (United States)

    Wang, Xianghong; Yan, Shunjie; Song, Lingjie; Shi, Hengchong; Yang, Huawei; Luan, Shifang; Huang, Yubin; Yin, Jinghua; Khan, Ather Farooq; Zhao, Jie

    2017-11-22

    Unlike conventional poly(N-isopropylacrylamide) (PNIPAM)-based surfaces switching from bactericidal activity to bacterial repellency upon decreasing temperature, we developed a hierarchical polymer architecture, which could maintain bactericidal activities at room temperature while presenting bacterial repellency at physiological temperature. In this architecture, a thermoresponsive bactericidal upper layer consisting of PNIPAM-based copolymer and vancomycin (Van) moieties was built on an antifouling poly(sulfobetaine methacrylate) (PSBMA) bottom layer via sequential surface-initiated photoiniferter-mediated polymerization. At room temperature below the lower critical solution temperature (LCST), the PNIPAM-based upper layer was stretchable, facilitating contact killing of bacteria by Van. At physiological temperature (above the LCST), the PNIPAM-based layer collapsed, thus leading to the burial of Van and exposure of bottom PSBMA brushes, finally displaying notable performances in bacterial inhibition, dead bacteria detachment, and biocompatibility, simultaneously. Our strategy provides a novel pathway in the rational design of temperature-sensitive switchable surfaces, which shows great advantages in the real-world infection-resistant applications.

  4. Bactericidal dental nanocomposites containing 1,2,3-triazolium-functionalized POSS additive prepared through thiol-ene click polymerization.

    Science.gov (United States)

    Burujeny, Saeed Beigi; Yeganeh, Hamid; Atai, Mohammad; Gholami, Hoshyar; Sorayya, Marziyeh

    2017-01-01

    Deterioration of mechanical strength for the dental composite containing ionic bactericidal compounds restricts the widespread utilization of this class of useful materials. This problem is originated from the reduction of the intermolecular interaction of polymeric network due to plasticization effect of absorbed water molecules penetrated between the chain segments. The main goal of this study is the synthesis of the highly efficient bactericidal additive with low hydrophilicity and consequently the least adverse effect on the final mechanical strength of the dental composite. The bactericidal 1, 2, 3-triazolium functional groups were chemically anchored on the surface of hydrophobic POSS nanoparticles (Triazolium-POSS) and incorporated into a dental restorative system composed of a ternary thiol-allyl ether-methacrylate resin and glass fillers. A similar system was also prepared, in which the POSS additive was replaced with quaternized dimethyl aminoethyl methacrylate monomer (DMAEMA-BC). The chemical structure of POSS derivatives was evaluated by 1 HNMR and FTIR spectra. The water uptake of dental composites was evaluated at days 1 and 14 after immersion into water. The bactericidal activity of composite specimens against Streptococcus mutans (ATCC 35668) was determined based on ASTM E 2180 - 07. The flexural properties of samples were investigated through three-point bending assay and the shrinkage-strain of photo-cured resins was measured using the bonded-disk technique. The degree of conversion (DC %) of methacrylate functions was followed by FTIR spectroscopy. MTT assay was performed to investigate the cytocompatibility of samples. Regardless of the partial increase in water uptake for Triazolium-POSS-containing sample, this parameter was much favor than the composite made from DMAEMA-BC. Therefore, the lower decline in flexural properties was recorded under the wet condition for the former system. Incorporation of Triazolium-POSS had no significant effect

  5. Convenient Preparation of Bactericidal Hydrogels by Covalent Attachment of Stabilized Antimicrobial Peptides Using Thiol-ene Click Chemistry

    NARCIS (Netherlands)

    Cleophas, Rik T. C.; Riool, Martijn; van Ufford, H. C. Quarles; Zaat, Sebastian A. J.; Kruijtzer, John A. W.; Liskamp, Rob M. J.

    2014-01-01

    This report describes the design and synthesis of a bactericidal poly(ethylene glycol)-based (PEG) hydrogel coating with covalently attached antimicrobial peptides (AMP) stabilized against proteolytic degradation. As such, mimics of the highly active AMP HHC10 (H-KRWWKWIRW-NH2) were designed for

  6. Synergistic bactericidal effects of a sublethal concentration of didecyldimethylammonium chloride (DDAC) and low concentrations of nonionic surfactants against Staphylococcus aureus.

    Science.gov (United States)

    Gomi, Mitsuhiro; Osaki, Yukihiko; Mori, Miho; Sakagami, Yoshikazu

    2012-01-01

    DDAC is an effective disinfectant used in the medical and food industries and the environmental field. However, skin irritation in humans occurs at high DDAC concentrations. In this study, we analyzed the combined effect of a low concentration (0.3 ppm) of DDAC and low concentrations (6, 8, and 10 ppm) of 37 products of nonionic surfactants on the bactericidal activity against S. aureus. No bactericidal activity was found at 0.3 ppm DDAC alone. Results showed that a combination of a low concentration of DDAC (0.3 ppm) and some nonionic surfactants tested (synergistic effect of five products ≥ 2.0) improved the bactericidal activity of DDAC. Synergistic effects of DDAC and some nonionic surfactants are desirable and were suggested to occur as follows. Test surfactants acted against the cell walls of S. aureus, which allowed DDAC to act easily on the lipid double membrane in the cell wall, thereby increasing the bactericidal activity of DDAC. In the present study, synergistic effects of a low concentration of DDAC and some nonionic surfactants were observed, a phenomenon that may be considerable value in future developments.

  7. The Application of Bactericidal Silver Nanoparticles in Wound Treatment

    Directory of Open Access Journals (Sweden)

    Geewoo Nam

    2015-07-01

    Full Text Available Even with the prevalence of wounds, the medical technol‐ ogy for efficiently managing skin damage is still primitive. The disruption of any of the numerous healing processes can lead to problems in the time-sensitive healing actions of the dermal and epidermal layers. Bacterial infection is one of the major obstacles to proper wound healing as it poses a danger of causing long-term negative effects. Keeping the wound free of bacteria is imperative to the proper and hasty repair of dermal wounds. Silver has been widely used to treat wounds for its bactericidal properties. Although the mechanism of silver’s antibacterial action is not fully understood, it exhibits a significant antimicrobial efficacy against a wide spectrum of bacterial species. A number of different approaches to the mechanism are reported and presented in this review. Silver nanoparticles (AgNPs have been reported to exhibit enhanced antibac‐ terial activity due to their increased surface-area-to-volume ratio. AgNPs are capable of various modifications, signifi‐ cantly broadening the therapeutic properties of the mate‐ rial as a result. This review explores the different aspects of silver and silver nanoparticles, and their antibacterial properties, which can be applied in the field of wound treatments.

  8. Active Recovery between Interval Bouts Reduces Blood Lactate While Improving Subsequent Exercise Performance in Trained Men

    Directory of Open Access Journals (Sweden)

    Harutiun M. Nalbandian

    2017-06-01

    Full Text Available This study aimed to examine the blood lactate and blood pH kinetics during high-intensity interval training. Seventeen well-trained athletes exercised on two different occasions. Exercises consisted of three 30 s bouts at a constant intensity (90% of peak power with 4 min recovery between bouts followed by a Wingate test (WT. The recoveries were either active recovery (at 60% of the lactate threshold intensity or passive recovery (resting at sitting position. During the exercise, blood samples were taken to determine blood gasses, blood lactate, and blood pH, and peak and average power were calculated for the WT. When performing the active recovery trials, blood pH was significantly higher (p < 0.01 and blood lactate was significantly lower (p < 0.01 compared with the passive recovery trials. WT performance was significantly higher in the active recovery trials: peak power was 671 ± 88 and 715 ± 108 watts, and average power was 510 ± 70 and 548 ± 73 watts (passive and active respectively; p < 0.01. However, no statistically significant correlations were found between the increased pH and the increased performance in the active recovery trials. These results suggest that active recovery performed during high-intensity interval exercise favors the performance in a following WT. Moreover, the blood pH variations associated with active recovery did not explain the enhanced performance.

  9. Impact of Physical Activity Interventions on Blood Pressure in Brazilian Populations

    OpenAIRE

    Bento, Vivian Freitas Rezende; Albino, Flávia Barbizan; de Moura, Karen Fernandes; Maftum, Gustavo Jorge; dos Santos, Mauro de Castro; Guarita-Souza, Luiz César; Faria Neto, José Rocha; Baena, Cristina Pellegrino

    2015-01-01

    Background: High blood pressure is associated with cardiovascular disease, which is the leading cause of mortality in the Brazilian population. Lifestyle changes, including physical activity, are important for lowering blood pressure levels and decreasing the costs associated with outcomes. Objective: Assess the impact of physical activity interventions on blood pressure in Brazilian individuals. Methods: Meta-analysis and systematic review of studies published until May 2014, retrieved from ...

  10. Enzyme activity of antiradical protection in case of ultraviolet irradiation of blood

    International Nuclear Information System (INIS)

    Shabunevich, L.V.; Aleksandrova, L.A.; Perelygin, V.G.

    1986-01-01

    The state of free radical processes and activity of antiradical protection enzymes are investigated for patients with lymphostatis of lower extremities, who have been treated by UV-irradiated blood autotransfusion. An increase in the activity of ceruloplasmin and superoxidedismutase of erythrocytes, which is considered to be one of the mechanisms of positive effect of UV-irradiated blood transfusion, is shown

  11. Effects of ABO/Rh blood groups, G-6-P-D enzyme activity and ...

    African Journals Online (AJOL)

    Effects of ABO/Rh blood groups, G-6-P-D enzyme activity and haemoglobin. Theresa K Nkuo-Akenji, Paul Wepngong, Jane-Frances Akoachere. Abstract. The main objective was to investigate the effects of ABO/Rh blood groups, haemoglobin genotype and G-6-P-D enzyme activity on malaria. The study was carried out in ...

  12. Transthyretin-Binding Activity of Contaminants in Blood from Polar Bear (Ursus maritimus) Cubs

    NARCIS (Netherlands)

    Bytingsvik, J.; Simon, E.; Leonards, P.E.G.; Lamoree, M.H.; Lie, E.; Aars, J.; Derocher, A. E.; Wiig, O.; Jenssen, B.M.; Hamers, T.

    2013-01-01

    We determined the transthyretin (TTR)-binding activity of blood-accumulating contaminants in blood plasma samples of approximately 4-months-old polar bear (Ursus maritimus) cubs from Svalbard sampled in 1998 and 2008. The TTR-binding activity was measured as thyroxine (T4)-like equivalents (T4-EQ

  13. Leptospira interrogans activation of peripheral blood monocyte glycolipoprotein demonstrated in whole blood by the release of IL-6

    Directory of Open Access Journals (Sweden)

    F. Dorigatti

    2005-06-01

    Full Text Available Glycolipoprotein (GLP from pathogenic serovars of Leptospira has been implicated in the pathogenesis of leptospirosis by its presence in tissues of experimental animals with leptospirosis, the inhibition of the Na,K-ATPase pump activity, and induced production of cytokines. The aims of the present study were to investigate the induction of IL-6 by GLP in peripheral blood mononuclear cells (PBMC and to demonstrate monocyte stimulation at the cellular level in whole blood from healthy volunteers. PBMC were stimulated with increasing concentrations (5 to 2500 ng/ml of GLP extracted from the pathogenic L. interrogans serovar Copenhageni, lipopolysaccharide (positive control or medium (negative control, and supernatants were collected after 6, 20/24, and 48 h, and kept at -80ºC until use. Whole blood was diluted 1:1 in RPMI medium and cultivated for 6 h, with medium, GLP and lipopolysaccharide as described above. Monensin was added after the first hour of culture. Supernatant cytokine levels from PBMC were measured by ELISA and intracellular IL-6 was detected in monocytes in whole blood cultures by flow-cytometry. Monocytes were identified in whole blood on the basis of forward versus side scatter parameters and positive reactions with CD45 and CD14 antibodies. GLP ( > or = 50 ng/ml-induced IL-6 levels in supernatants were detected after 6-h incubation, reaching a peak after 20/24 h. The percentage of monocytes staining for IL-6 increased with increasing GLP concentration. Thus, our findings show a GLP-induced cellular activation by demonstrating the ability of GLP to induce IL-6 and the occurrence of monocyte activation in whole blood at the cellular level.

  14. Physical Activity, BMI, and Blood Pressure in US Youth: NHANES 2003-2006.

    Science.gov (United States)

    Betz, Heather Hayes; Eisenmann, Joey C; Laurson, Kelly R; DuBose, Katrina D; Reeves, Mathew J; Carlson, Joseph J; Pfeiffer, Karin A

    2018-03-15

    The objective of this study was to examine the independent and combined association of physical activity and body mass index (BMI) with blood pressure in youth. Youth aged 8-18 years from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) with BMI, blood pressure, and physical activity (accelerometer) were included in the analyses. A total of 2585 subjects (1303 males; 47% of all 8- to 18-year-olds) met these criteria. Obese youth had a systolic blood pressure that was 8 mm Hg higher than normal weight youth. A significant interaction between BMI and physical activity on blood pressure was found (P activity groups showed that the 3 obese groups and the overweight/least active group had significantly higher systolic blood pressure than the normal weight/active group across all analyses. The overweight/least active and normal weight/least active groups had significantly higher diastolic blood pressure than the normal weight/active group as well. This study showed a significant independent and combined association of BMI and physical activity with blood pressure in youth. Interventions need to focus on the reduction of fatness/BMI as a way to reduce the cardiovascular risk in youth.

  15. Blood monocyte oxidative burst activity in acute P. falciparum malaria

    DEFF Research Database (Denmark)

    Nielsen, H; Theander, T G

    1989-01-01

    The release of superoxide anion from blood monocytes was studied in eight patients with acute primary attack P. falciparum malaria. Before treatment a significant enhancement of the oxidative burst prevailed, which contrasts with previous findings of a depressed monocyte chemotactic responsiveness...

  16. Blood glucose lowering activity of five Nigerian medicinal plants in ...

    African Journals Online (AJOL)

    The blood glucose lowering effects of the aqueous leaf extracts of Cassia alata, Acalypha torta and Breynia nivosa, and aqueous root extracts of Daniellia oliveri and Nauclea latifolia traditionally employed in Nigeria in the management of diabetes mellitus were compared in alloxan-induced diabetic Wistar rats. The same ...

  17. Biomaterials trigger endothelial cell activation when co-incubated with human whole blood.

    Science.gov (United States)

    Herklotz, Manuela; Hanke, Jasmin; Hänsel, Stefanie; Drichel, Juliane; Marx, Monique; Maitz, Manfred F; Werner, Carsten

    2016-10-01

    Endothelial cell activation resulting from biomaterial contact or biomaterial-induced blood activation may in turn also affect hemostasis and inflammatory processes in the blood. Current in vitro hemocompatibility assays typically ignore these modulating effects of the endothelium. This study describes a co-incubation system of human whole blood, biomaterial and endothelial cells (ECs) that was developed to overcome this limitation. First, human endothelial cells were characterized in terms of their expression of coagulation- and inflammation-relevant markers in response to various activators. Subsequently, their capacity to regulate hemostasis as well as complement and granulocyte activation was monitored in a hemocompatibility assay. After blood contact, quiescent ECs exhibited anticoagulant and anti-inflammatory properties. When they were co-incubated with surfaces exhibiting pro-coagulant or pro-inflammatory characteristics, the ECs down-regulated coagulation but not complement or leukocyte activation. Analysis of intracellular levels of the endothelial activation markers E-selectin and tissue factor showed that co-incubation with model surfaces and blood significantly increased the activation state of ECs. Finally, the coagulation- and inflammation-modulating properties of the ECs were tested after blood/biomaterial exposure. Pre-activation of ECs by biomaterials in the blood induced a pro-coagulant and pro-inflammatory state of the ECs, wherein the pro-coagulant response was higher for biomaterial/blood pre-activated ECs than for TNF-α-pre-activated cells. This work provides evidence that biomaterials, even without directly contacting the endothelium, affect the endothelial activation state with and have consequences for plasmatic and cellular reactions in the blood. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Bactericidal Effect of Photolysis of H2O2 in Combination with Sonolysis of Water via Hydroxyl Radical Generation.

    Science.gov (United States)

    Sheng, Hong; Nakamura, Keisuke; Kanno, Taro; Sasaki, Keiichi; Niwano, Yoshimi

    2015-01-01

    The bactericidal effect of hydroxyl radical (·OH) generated by combination of photolysis of hydrogen peroxide (H2O2) and sonolysis of water was examined under the condition in which the yield of ·OH increased additively when H2O2 aqueous solution was concomitantly irradiated with laser and ultrasound. The suspension of Staphylococcus aureus mixed with the different concentrations of H2O2 was irradiated simultaneously with a laser light (wavelength: 405 nm, irradiance: 46 and 91 mW/cm2) and ultrasound (power: 30 w, frequency: 1.65 MHz) at 20 ± 1°C of the water bulk temperature for 2 min. The combination of laser and ultrasound irradiation significantly reduced the viable bacterial count in comparison with the laser irradiation of H2O2 alone. By contrast, the ultrasound irradiation alone exerted almost no bactericidal effect. These results suggested that the combination effect of photolysis of H2O2 and sonolysis of water on bactericidal activity was synergistic. A multi-way analysis of variance also revealed that the interaction of H2O2 concentration, laser power and ultrasound irradiation significantly affected the bactericidal activity. Since the result of oxidative DNA damage evaluation demonstrated that the combination of laser and ultrasound irradiation significantly induced oxidative damage of bacterial DNA in comparison with the laser irradiation of H2O2 alone, it was suggested that the combination effect of photolysis of H2O2 and sonolysis of water on bactericidal activity would be exerted via oxidative damage of cellular components such as DNA.

  19. Bactericidal effect of hydroxyl radicals generated by the sonolysis and photolysis of hydrogen peroxide for endodontic applications.

    Science.gov (United States)

    Ibi, Haruna; Hayashi, Makoto; Yoshino, Fumihiko; Tamura, Muneaki; Yoshida, Ayaka; Kobayashi, Yoshimi; Shimizu, Kohei; Lee, Masaichi-Chang-Il; Imai, Kenichi; Ogiso, Bunnai

    2017-02-01

    The aim of endodontic root canal treatment is the elimination of bacteria and their products from an infected tooth root canal. To effectively disinfect a root canal, an ultrasonic irrigation system, in which hydroxyl radicals (HO · ) generated artificially by sonolysis of H 2 O 2 , was developed previously for endodontic applications and was demonstrated to have bactericidal efficacy against Enterococcus faecalis. To improve this system, we examined the in vitro bactericidal effects of HO · generated from H 2 O 2 , activated by simultaneous irradiation with ultrasound for sonolysis and dental LED light for photolysis with a peak wavelength of 405 nm. Regarding the LED irradiation, two methods were used: (i) 'ideal' experimental conditions (irradiation close to the glass tube), and (ii) simulated endodontic conditions (more distant irradiation of a masked glass tube). In these conditions, HO · generation from H 2 O 2 was detected by electron spin resonance (ESR) spectroscopy, and bactericidal efficacy against E. faecalis was assessed by measuring the colony forming units (CFU)/mL. The results indicated that HO · generation by ESR measurements and the bactericidal effect on E. faecalis by viable count using CFU/mL were enhanced significantly in a time-dependent manner in both conditions. In a comparison of these conditions, bactericidal activity under 'ideal' experimental conditions was similar to that under simulated endodontic conditions. Moreover, the irradiation time for effective killing of E. faecalis through the sonolysis and photolysis of H 2 O 2 under simulated endodontic conditions was shorter than that with sonolysis alone. These results demonstrate that H 2 O 2 activated by ultrasound and LED light may be a safe and effective disinfection technique for endodontic root canal treatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Effect of occupational lead-exposure on blood pressure, serum aldosterone level and plasma renin activity.

    Science.gov (United States)

    Shouman, A E; El-Safty, I A

    2000-01-01

    Numerous observations have indicated a relationship between lead exposure and elevated blood pressure. The present study aims to investigate the association between occupational lead-exposure and elevated blood pressure as well as serum aldosterone level and plasma renin activity as parameters affecting blood pressure. Fifty occupationally lead-exposed (16 males and 34 females) and 50 non-exposed (15 males and 34 females) workers were selected after application of certain exclusion criteria. All workers were admitted to complete clinical examination, including standard blood pressure measurement. Also, blood lead level, serum aldosterone concentration and plasma renin activity were estimated. The results of both occupationally lead-exposed males and females demonstrated no significant differences regarding age, work duration, systolic and diastolic blood pressures when compared to occupationally non-exposed males and females; respectively. In addition, occupationally lead-exposed males and females revealed a significant increase in blood lead level and serum aldosterone concentration in comparison to their controls. Moreover, plasma renin activity is significantly decreased among the lead-exposed male workers while it is significantly increased among the lead-exposed female workers in comparison to their controls. It is concluded that serum aldosterone level and plasma renin activity are affected by occupationally low-level of lead exposure, and the present study provide further support for the association between blood lead exposure and blood pressure related hormones.

  1. Alpha-Amylase Activity in Blood Increases after Pharmacological, But Not Psychological, Activation of the Adrenergic System.

    Directory of Open Access Journals (Sweden)

    Urs M Nater

    Full Text Available Alpha-amylase in both blood and saliva has been used as a diagnostic parameter. While studies examining alpha-amylase activity in saliva have shown that it is sensitive to physiological and psychological challenge of the adrenergic system, no challenge studies have attempted to elucidate the role of the adrenergic system in alpha-amylase activity in blood. We set out to examine the impact of psychological and pharmacological challenge on alpha-amylase in blood in two separate studies.In study 1, healthy subjects were examined in a placebo-controlled, double-blind paradigm using yohimbine, an alpha2-adrenergic antagonist. In study 2, subjects were examined in a standardized rest-controlled psychosocial stress protocol. Alpha-amylase activity in blood was repeatedly measured in both studies.Results of study 1 showed that alpha-amylase in blood is subject to stronger increases after injection of yohimbine compared to placebo. In study 2, results showed that there was no significant effect of psychological stress compared to rest.Alpha-amylase in blood increases after pharmacological activation of the adrenergic pathways suggesting that sympathetic receptors are responsible for these changes. Psychological stress, however, does not seem to have an impact on alpha-amylase in blood. Our findings provide insight into the mechanisms underlying activity changes in alpha-amylase in blood in healthy individuals.

  2. Silver nanoparticles influence on the blood activation process and their release to blood plasma from synthetic polymer scaffold

    Science.gov (United States)

    Major, R.; Lackner, J. M.; Sanak, M.; Major, B.

    2016-03-01

    In the present work, blood and blood plasma interaction to silver stabilised polyelectrolytes was investigated in vitro. The designed materials are dedicated for regeneration of the cardiovascular system. Silver nanoparticles were introduced into the polyelectrolyte structure in order to reduce the risk of bacterial biofilm formation. The introduction of Ag nanoparticles occurred by deposition at high vacuum by magnetron sputtering. The analysis of blood-materials interactions were performed by using commercially available tester, Impact-R (Diamed). The assessment of silver ion nanoparticles release into the plasma consisted in determining the Prothrombin Time (PT) and Activated Partial Thromboplastin Time (APTT). Unmodified surface of polyelectrolytes is a strong activator for blood elements. The introduction of silver nanoparticles resulted in a significant reduction in the probability of clotting. The extrinsic pathway of coagulation determined on the basis of the PT and the intrinsic and common pathways of coagulation measured by the APTT did not indicate the danger out of range. Microstructure was studied using TEM on thin foils prepared from the cross-section of samples subjected to biomedical treatments. The observations revealed hetero- interface between two different crystalline solids.

  3. BOLD-specific cerebral blood volume and blood flow changes during neuronal activation in humans.

    Science.gov (United States)

    Chen, J Jean; Pike, G Bruce

    2009-12-01

    To understand and predict the blood-oxygenation level-dependent (BOLD) fMRI signal, an accurate knowledge of the relationship between cerebral blood flow (DeltaCBF) and volume (DeltaCBV) changes is critical. Currently, this relationship is widely assumed to be characterized by Grubb's power-law, derived from primate data, where the power coefficient (alpha) was found to be 0.38. The validity of this general formulation has been examined previously, and an alpha of 0.38 has been frequently cited when calculating the cerebral oxygen metabolism change (DeltaCMRo(2)) using calibrated BOLD. However, the direct use of this relationship has been the subject of some debate, since it is well established that the BOLD signal is primarily modulated by changes in 'venous' CBV (DeltaCBV(v), comprising deoxygenated blood in the capillary, venular, and to a lesser extent, in the arteriolar compartments) instead of total CBV, and yet DeltaCBV(v) measurements in humans have been extremely scarce. In this work, we demonstrate reproducible DeltaCBV(v) measurements at 3 T using venous refocusing for the volume estimation (VERVE) technique, and report on steady-state DeltaCBV(v) and DeltaCBF measurements in human subjects undergoing graded visual and sensorimotor stimulation. We found that: (1) a BOLD-specific flow-volume power-law relationship is described by alpha = 0.23 +/- 0.05, significantly lower than Grubb's constant of 0.38 for total CBV; (2) this power-law constant was not found to vary significantly between the visual and sensorimotor areas; and (3) the use of Grubb's value of 0.38 in gradient-echo BOLD modeling results in an underestimation of DeltaCMRo(2).

  4. Endothelial Dysfunction and Blood Viscosity Inpatients with Unstable Angina in Different Periods of a Solar Activity

    Science.gov (United States)

    Parshina, S. S.; Tokaeva, L. K.; Dolgova, E. M.; Afanas'yeva, T. N.; Strelnikova, O. A.

    The origin of hemorheologic and endothelial defects in patients with unstable angina (comparing with healthy persons) is determined by a solar activity period: the blood viscosity increases in a period of high solar activity in the vessels of small, medium and macro diameters, a local decompensate dysfunction of small vessels endothelium had been fixed (microcirculation area). In the period of a low solar activity there is an increase of a blood viscosity in vessels of all diameters, generalized subcompensated endothelial dysfunction is developed (on the background of the III phase blood clotting activating). In the period of a high solar activity a higher blood viscosity had been fixed, comparing with the period of a low solar activity.

  5. Stem Cells and Progenitors in Human Peripheral Blood Get Activated by Extremely Active Resveratrol (XAR™).

    Science.gov (United States)

    Tripathi, Vinaykumar; Chhabria, Sagar; Jadhav, Vaibhav; Bhartiya, Deepa; Tripathi, Ashish

    2017-11-24

    Resveratrol generated enormous interest as it improved functions of multiple organs and could delay aging in animal models. However, basic mechanism of action was not understood and due to poor bioavailability, it has failed to enter the market. A highly active nano-formulation of resveratrol (XAR™) with enhanced bioavailability is now available. Present study was undertaken to evaluate its effects on stem cells biology in the human peripheral blood. Twelve healthy participants were enrolled of which five received XAR™, five were age-matched placebo controls and two were 76 and 85 years old. Peripheral blood was processed to study serum profile to monitor cardiac and pancreatic functions and subjected to density gradient centrifugation to enrich pluripotent (VSELs) and adult stem cells that get enriched along with red blood cells and in the Buffy coat respectively on Day 2 and Day 15 after XAR™ treatment. The XAR™ treatment resulted in an increased expression of pluripotency transcripts specific for VSELs (Oct-4A, Nanog and Sox2) on D2; specific transcripts for differentiation in the progenitors including Oct-4, Ikaros, CD14, CD90 on D15, and anti-ageing and tumor suppressor transcripts NAD, SIRT1, SIRT6 and p53 in both stem cells and progenitors. An improvement of cardiac and pancreatic markers in serum profile was also observed on D15. The decline in VSELs numbers with age and beneficial effects of the XAR™ treatment were evident by up-regulation of specific transcripts and on serum profile. XAR™ is a promising molecule that has the potential to activate pluripotent VSELs and tissue committed adult stem cells 'progenitors' resulting in the rejuvenation of various body tissues and for improved, cancer-free health with advanced age.

  6. SOLAR ACTIVITY AND PECULIARITIES OF THE RHEOLOGICAL PROPERTIES OF THE BLOOD IN PATIENTS WITH ANGINA PECTORIS

    Directory of Open Access Journals (Sweden)

    T.N. Afanasjeva

    2008-03-01

    Full Text Available The peculiarities of the rheological properties of the blood are studied in patients with non-stable angina pectohs in different perbds of solar activity. It has been established, that in high solar activity hemorheological disorders are characterized by increase of blood viscosity and compensatory decrease oferythrocyte aggregation and increase of their deformation. In low solar activity less perceptible hyperviscositywas accompanied by significant increase oferythrocyte aggregation and decrease of their deformity capacity.

  7. Resistin-like molecule β is a bactericidal protein that promotes spatial segregation of the microbiota and the colonic epithelium.

    Science.gov (United States)

    Propheter, Daniel C; Chara, Andrew L; Harris, Tamia A; Ruhn, Kelly A; Hooper, Lora V

    2017-10-17

    The mammalian intestine is colonized by trillions of bacteria that perform essential metabolic functions for their hosts. The mutualistic nature of this relationship depends on maintaining spatial segregation between these bacteria and the intestinal epithelial surface. This segregation is achieved in part by the presence of a dense mucus layer at the epithelial surface and by the production of antimicrobial proteins that are secreted by epithelial cells into the mucus layer. Here, we show that resistin-like molecule β (RELMβ) is a bactericidal protein that limits contact between Gram-negative bacteria and the colonic epithelial surface. Mouse and human RELMβ selectively killed Gram-negative bacteria by forming size-selective pores that permeabilized bacterial membranes. In mice lacking RELMβ, Proteobacteria were present in the inner mucus layer and invaded mucosal tissues. Another RELM family member, human resistin, was also bactericidal, suggesting that bactericidal activity is a conserved function of the RELM family. Our findings thus identify the RELM family as a unique family of bactericidal proteins and show that RELMβ promotes host-bacterial mutualism by regulating the spatial segregation between the microbiota and the intestinal epithelium.

  8. Naturally occurring bactericidal antibodies specific for Haemophilus influenzae lipooligosaccharide are present in healthy adult individuals.

    Science.gov (United States)

    Choi, Joshua; Nix, Eli B; Gaultier, Gabrielle N; Cox, Andrew D; McCready, William; Ulanova, Marina

    2015-04-15

    Nontypeable Haemophilus influenzae (NTHi), a typical mucosal pathogen largely responsible for respiratory infections and pediatric otitis media, has been increasingly recognized as a significant cause of invasive disease, especially in immunocompromised individuals. Lipooligosaccharide (LOS) is a conserved molecule with an important role in H. influenzae virulence and immune evasion, and it may be considered as a vaccine candidate. However, abilities of H. influenzae LOS to induce protective immune response are poorly understood. The goal of this study was to determine whether antibodies against LOS isolated from H. influenzae strains Eagan, Rd and NTHi 375 are present in the sera of normal individuals. Antigen specific IgG and IgM were studied in sera of 71 and 30 healthy adults, respectively. IgG specific for LOS of all three strains was ubiquitously present in our sample population while IgM specific for Eagan, Rd and NTHi 375 LOS compounds was detected in 37%, 63%, and 40% of samples, respectively. All tested serum samples exhibited bactericidal activity against all three H. influenzae strains; the removal of anti-LOS antibodies from the sera resulted in significant increases in bacterial survival of the corresponding strain. NTHi 375 exhibited the highest serum resistance, whereas the Rd strain was the least resistant. Serum bactericidal activity of anti-LOS antibody was mediated via the classical complement pathway. These findings suggest that in healthy adults, naturally acquired complement-activating anti-LOS antibodies significantly contribute to the overall serum bactericidal activity against both encapsulated and non-encapsulated strains of H. influenzae. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Disclosure of the quackery: Testing of the bactericidal action of ...

    African Journals Online (AJOL)

    The obtained results indicate a fraud: bactericidal effect is rather a result of photocatalytic action of a hidden component used on purpose in the production of glass or subsequently applied by the use of nanotechnology (possibly antimony trioxide or titanium oxide) than of the so-called ''orgon and hydronic technology''.

  10. Bactericidal effects of reactive thermal plasma synthesized titanium dioxide photocatalysts

    Czech Academy of Sciences Publication Activity Database

    Vijay, M.; Selvarajan, V.; Ananthapadmanabhan, P.V.; Sreekumar, K.P.; Štengl, Václav; Bondioli, F.

    2010-01-01

    Roč. 208, - (2010), 012143/1-012143/8 E-ISSN 1742-6596 R&D Projects: GA ČR GA203/08/0334 Institutional research plan: CEZ:AV0Z40320502 Keywords : a-thermal * analytical tool * anatase phase * Bactericidal action Subject RIV: CA - Inorganic Chemistry

  11. In-vitro Bactericidal Kinetics of Chlorhexidine Gluconate Disinfectant ...

    African Journals Online (AJOL)

    Chlorhexidine gluconate(CHG) is a popular disinfectant/antiseptic which is often formulated with additives. We investigated the effect of additives type on the in vitro bactericidal kinetics of CHG in three commercially available formulations: Hibiscrub®, Savlon® and Purit® commonly used as household and hospital ...

  12. The Impact of 200 Meter Breast Stroke Swimming Activity on Blood Glucose Level of The Student

    Science.gov (United States)

    Syahrastani, S.; Badri, H.; Argantos, A.; Yuniarti, E.

    2018-04-01

    Blood sugar in the human body is very important, as it is a source of energy for humans. Fasting blood sugar needs to be recognized, because it is an indicator of a person’s health. The research that has been done aims to determine the effect of physical activity on fasting blood sugar. This research is a quasi-experimental research. The research was conducted on 15 students of FIK UNP Padang, who have passed the swimming course. Blood was taken before and after doing physical exercise activity of 200 meter breaststroke swimming. Data collection was conducted with tests and measurements. The data analysis technique used inference statistics with t test formula, with α = 0.05. From the results it is obtained that there is a very significant impact on blood sugar levels after 200 meters breaststroke swimming activity with p <0.05

  13. Ambulatory blood pressure monitoring : effect of physical activity

    NARCIS (Netherlands)

    M.N. Cavelaars (Marinel)

    2004-01-01

    textabstractThe present thesis deals with the effects of physical activity and body posture on ambulatory BP and systemic haemodynamics in normotensive and hypertensive individuals. The Activity Monitor, i.e., the method used to measure physical activity and posture, is the constant factor in the

  14. Impact of Physical Activity Interventions on Blood Pressure in Brazilian Populations

    Directory of Open Access Journals (Sweden)

    Vivian Freitas Rezende Bento

    2015-01-01

    Full Text Available Background: High blood pressure is associated with cardiovascular disease, which is the leading cause of mortality in the Brazilian population. Lifestyle changes, including physical activity, are important for lowering blood pressure levels and decreasing the costs associated with outcomes. Objective: Assess the impact of physical activity interventions on blood pressure in Brazilian individuals. Methods: Meta-analysis and systematic review of studies published until May 2014, retrieved from several health sciences databases. Seven studies with 493 participants were included. The analysis included parallel studies of physical activity interventions in adult populations in Brazil with a description of blood pressure (mmHg before and after the intervention in the control and intervention groups. Results: Of 390 retrieved studies, eight matched the proposed inclusion criteria for the systematic review and seven randomized clinical trials were included in the meta-analysis. Physical activity interventions included aerobic and resistance exercises. There was a reduction of -10.09 (95% CI: -18.76 to -1.43 mmHg in the systolic and -7.47 (95% CI: -11.30 to -3.63 mmHg in the diastolic blood pressure. Conclusions: Available evidence on the effects of physical activity on blood pressure in the Brazilian population shows a homogeneous and significant effect at both systolic and diastolic blood pressures. However, the strength of the included studies was low and the methodological quality was also low and/or regular. Larger studies with more rigorous methodology are necessary to build robust evidence.

  15. Bactericidal effects of plasma-modified surface chemistry of silicon nanograss

    Science.gov (United States)

    Ostrikov, Kola; Macgregor-Ramiasa, Melanie; Cavallaro, Alex; (Ken Ostrikov, Kostya; Vasilev, Krasimir

    2016-08-01

    The surface chemistry and topography of biomaterials regulate the adhesion and growth of microorganisms in ways that are still poorly understood. Silicon nanograss structures prepared via inductively coupled plasma etching were coated with plasma deposited nanometer-thin polymeric films to produce substrates with controlled topography and defined surface chemistry. The influence of surface properties on Staphylococcus aureus proliferation is demonstrated and explained in terms of nanograss substrate wetting behaviour. With the combination of the nanograss topography; hydrophilic plasma polymer coatings enhanced antimicrobial activity while hydrophobic coatings reduced it. This study advances the understanding of the effects of surface wettability on the bactericidal properties of reactive nano-engineered surfaces.

  16. Bactericidal action of a glycoprotein from the body surface mucus of giant African snail.

    Science.gov (United States)

    Otsuka-Fuchino, H; Watanabe, Y; Hirakawa, C; Tamiya, T; Matsumoto, J J; Tsuchiya, T

    1992-04-01

    1. Bactericidal action of a glycoprotein, Achacin, purified from the giant African snail, Achatina fulica Férussac, has been studied. 2. Achacin kills both gram-positive and gram-negative bacteria, but only in their growing states. 3. Achacin does not have any bacteriolytic activity. 4. The strain which has no cell wall is a little more sensitive than the native strain and the cell membrane-damaged strain. 5. Achacin was observed on the cytoplasmic membrane and on the cell wall of treated Escherichia coli by immunoelectron microscopy. 6. Achacin attacks the cytoplasmic membrane of the cell.

  17. Bactericidal effects of plasma-modified surface chemistry of silicon nanograss

    International Nuclear Information System (INIS)

    Ostrikov, Kola; Macgregor-Ramiasa, Melanie; Cavallaro, Alex; Ostrikov, Kostya; Vasilev, Krasimir

    2016-01-01

    The surface chemistry and topography of biomaterials regulate the adhesion and growth of microorganisms in ways that are still poorly understood. Silicon nanograss structures prepared via inductively coupled plasma etching were coated with plasma deposited nanometer-thin polymeric films to produce substrates with controlled topography and defined surface chemistry. The influence of surface properties on Staphylococcus aureus proliferation is demonstrated and explained in terms of nanograss substrate wetting behaviour. With the combination of the nanograss topography; hydrophilic plasma polymer coatings enhanced antimicrobial activity while hydrophobic coatings reduced it. This study advances the understanding of the effects of surface wettability on the bactericidal properties of reactive nano-engineered surfaces. (paper)

  18. Engagement in Pleasant Leisure Activities and Blood Pressure: A 5-Year Longitudinal Study in Alzheimer Caregivers.

    Science.gov (United States)

    Mausbach, Brent T; Romero-Moreno, Rosa; Bos, Taylor; von Känel, Roland; Ziegler, Michael G; Allison, Matthew A; Mills, Paul J; Dimsdale, Joel E; Ancoli-Israel, Sonia; Losada, Andrés; Márquez-González, María; Patterson, Thomas L; Grant, Igor

    2017-09-01

    Elevated blood pressure is a significant public health concern, particularly given its association with cardiovascular disease risk, including stroke. Caring for a loved one with Alzheimer disease has been associated with physical health morbidity, including higher blood pressure. Engagement in adaptive coping strategies may help prevent blood pressure elevation in this population. This 5-year longitudinal study examined whether greater participation in pleasant leisure activities was associated with reduced blood pressure in caregivers. Participants were 126 in-home spousal Alzheimer's caregivers (M [SD] age = 74.2 [7.9] years) that completed five yearly assessments. Linear mixed-effects models analysis was used to examine the longitudinal relationship between pleasant leisure activities and caregivers' blood pressure, after adjusting for demographic and health characteristics. Greater engagement in pleasant leisure activities was associated with reduced mean arterial blood pressure (B = -0.08, SE = 0.04, p = .040). Follow-up analyses indicated that engagement in activities was significantly associated with reduced diastolic (B = -0.07, SE = 0.03, p = .030) but not systolic blood pressure (B = -0.10, SE = 0.06, p = .114). In addition, mean arterial blood pressure was significantly reduced when caregiving duties ended because of placement of care recipients in nursing homes (B = -3.10, SE = 1.11, p = .005) or death of the care recipient (B = -2.64, SE = 1.14, p = .021). Greater engagement in pleasant leisure activities was associated with lowered caregivers' blood pressure over time. Participation in pleasant leisure activities may have cardiovascular health benefits for Alzheimer's caregivers.

  19. Gliadin peptides activate blood monocytes from patients with celiac disease

    Czech Academy of Sciences Publication Activity Database

    Cinová, Jana; Palová-Jelínková, Lenka; Smythies, L.; Černá, M.; Pecharová, Barbara; Dvořák, M.; Fruhauf, P.; Tlaskalová, Helena; Smith, P.; Tučková, Ludmila

    2007-01-01

    Roč. 27, č. 2 (2007), s. 201-209 ISSN 0271-9142 R&D Projects: GA ČR GA310/05/2245; GA ČR GD310/03/H147; GA AV ČR IAA5020210; GA AV ČR IAA5020205; GA AV ČR 1QS500200572; GA AV ČR KJB5020407; GA MZe 1B53002 Grant - others:US(US) DK-064400; US(US) DK-47322; US(US) DK-54495; US(US) HD-41361; US(US) DK-064400 Institutional research plan: CEZ:AV0Z50200510 Source of funding: N - neverejné zdroje ; N - neverejné zdroje ; N - neverejné zdroje ; N - neverejné zdroje ; N - neverejné zdroje Keywords : celiac disease * innate immunity * blood monocytes Subject RIV: EE - Microbiology, Virology Impact factor: 2.886, year: 2007

  20. Cysteine peroxidase activity in rat blood plasma | Razygraev ...

    African Journals Online (AJOL)

    The rat plasma found to be able to accelerate greatly the H2O2-dependent oxidation of cysteine. The activity was a characteristic of a protein fraction precipitated at 30—44% ammonium sulfate saturation, and the specific activity in protein fraction was significantly higher than in plasma. Cysteine:H2O2 oxidoreductase ...

  1. Physical activity, change in blood pressure and predictors of ...

    African Journals Online (AJOL)

    Objective. A 2-year follow-up study of a cohort of 200 historically disadvantaged older South Africans was conducted to: (i) characterise current levels of habitual physical activity; (ii) relate physical activity to current risk factors for chronic disease; and (iii) identify risk factors associated with 2-year mortality. The baseline ...

  2. The bactericidal effect of carbon nanotube/agar composites irradiated with near-infrared light on Streptococcus mutans

    International Nuclear Information System (INIS)

    Akasaka, Tsukasa; Matsuoka, Makoto; Hashimoto, Takeshi; Abe, Shigeaki; Uo, Motohiro; Watari, Fumio

    2010-01-01

    Dental caries are mainly associated with oral pathogens, and Streptococcus mutans is a primary cariogenic organism. Many methods have been established to eliminate S. mutans from the oral cavity. This study aimed to evaluate the effect of carbon nanotube (CNT)/agar composites irradiated with near-infrared (NIR) light on S. mutans, as a potential photothermal antimicrobial nanotherapy. A colony-forming unit assay clearly showed that CNT/agar composites attain bactericidal activity after NIR light irradiation; this bactericidal activity is higher than that of graphite (GP)/agar and activated carbon (AC)/agar composites. Furthermore, it was observed that longer irradiation times immobilized S. mutans in the CNT/agar composite.

  3. The bactericidal effect of carbon nanotube/agar composites irradiated with near-infrared light on Streptococcus mutans

    Energy Technology Data Exchange (ETDEWEB)

    Akasaka, Tsukasa, E-mail: akasaka@den.hokudai.ac.jp [Graduate School of Dental Medicine, Hokkaido University, Kita13 Nishi7, Kita-ku, Sapporo 060-8586 (Japan); Matsuoka, Makoto [Graduate School of Dental Medicine, Hokkaido University, Kita13 Nishi7, Kita-ku, Sapporo 060-8586 (Japan); Hashimoto, Takeshi [Meijo Nano Carbon Co. Ltd., Otsubashi bldg. 4F, 3-4-10 Marunouchi, Naka-ku, Nagoya 460-0002 (Japan); Abe, Shigeaki; Uo, Motohiro; Watari, Fumio [Graduate School of Dental Medicine, Hokkaido University, Kita13 Nishi7, Kita-ku, Sapporo 060-8586 (Japan)

    2010-10-15

    Dental caries are mainly associated with oral pathogens, and Streptococcus mutans is a primary cariogenic organism. Many methods have been established to eliminate S. mutans from the oral cavity. This study aimed to evaluate the effect of carbon nanotube (CNT)/agar composites irradiated with near-infrared (NIR) light on S. mutans, as a potential photothermal antimicrobial nanotherapy. A colony-forming unit assay clearly showed that CNT/agar composites attain bactericidal activity after NIR light irradiation; this bactericidal activity is higher than that of graphite (GP)/agar and activated carbon (AC)/agar composites. Furthermore, it was observed that longer irradiation times immobilized S. mutans in the CNT/agar composite.

  4. Bactericidal effects of triclosan in soap both in vitro and in vivo.

    Science.gov (United States)

    Kim, S A; Moon, H; Lee, K; Rhee, M S

    2015-12-01

    On December 2013, the US FDA proposed a rule stating that manufacturers must provide data to demonstrate that antibacterial soap is more effective than plain soap or water. The objective of the present study was to examine the in vitro and in vivo bactericidal effect of triclosan (the most widely used antiseptic agent in soap) in soap. Twenty bacterial strains (proposed by the FDA) were exposed to plain and antibacterial soaps (the same formulation as plain soap, but containing 0.3% triclosan) for 20 s at 22°C (room temperature) and 40°C (warm temperature). The temperature and time were selected to simulate the hand washing conditions and procedures used by consumers. The triclosan concentration of 0.3% is the maximum allowed by law. The decontamination efficacy of plain soap and antibacterial soap was also examined in vivo: the hands of volunteers were artificially inoculated with Serratia marcescens. There was no significant difference (P > 0.05) in bactericidal activity between plain soap and antibacterial soap at either test temperature. However, antibacterial soap showed significantly greater bactericidal effects after 9 h. These results suggest that although triclosan-containing soap does have antibacterial activity, the effects are not apparent during the short time required for hand washing. Antibacterial soap containing triclosan (0.3%) was no more effective than plain soap at reducing bacterial contamination when used under 'real-life' conditions. The present study provides practical information that may prove useful for both industry and governments. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  5. [Modification of plasma blood coagulation factor activity by physical stress].

    Science.gov (United States)

    Lutze, G; Buhl, H; Häcker, R; Socha, C; Socha, U; Urbahn, H

    1986-09-15

    The influence of physical stress (bicycle ergometer and track) on 13 parameters of the plasmatic coagulation system was investigated in trained and untrained test persons. Shortenings of the coagulation times as well as distinct increases of the activity or concentration were observed in the partial thromboplastin time (PTT), the factor VIII activity (VIII:C) and the factor VIII-associated antigen (VIIIR:Ag). The results are discussed with regard to their causes and their clinical importance.

  6. Blood meal acquisition enhances arbovirus replication in mosquitoes through activation of the GABAergic system.

    Science.gov (United States)

    Zhu, Yibin; Zhang, Rudian; Zhang, Bei; Zhao, Tongyan; Wang, Penghua; Liang, Guodong; Cheng, Gong

    2017-11-02

    Mosquitoes are hematophagous insects that carry-on and transmit many human viruses. However, little information is available regarding the common mechanisms underlying the infection of mosquitoes by these viruses. In this study, we reveal that the hematophagous nature of mosquitoes contributes to arboviral infection after a blood meal, which suppresses antiviral innate immunity by activating the GABAergic pathway. dsRNA-mediated interruption of the GABA signaling and blockage of the GABA A receptor by the specific inhibitors both significantly impaired arbovirus replication. Consistently, inoculation of GABA enhanced arboviral infection, indicating that GABA signaling facilitates the arboviral infection of mosquitoes. The ingestion of blood by mosquitoes resulted in robust GABA production from glutamic acid derived from blood protein digestion. The oral introduction of glutamic acid increased virus acquisition by mosquitoes via activation of the GABAergic system. Our study reveals that blood meals enhance arbovirus replication in mosquitoes through activation of the GABAergic system.

  7. Blood Pressure, Sexual Activity, and Dysfunction in Women With Hypertension: Baseline Findings From the Systolic Blood Pressure Intervention Trial (SPRINT).

    Science.gov (United States)

    Foy, Capri G; Newman, Jill C; Berlowitz, Dan R; Russell, Laurie P; Kimmel, Paul L; Wadley, Virginia G; Thomas, Holly N; Lerner, Alan J; Riley, William T

    2016-09-01

    Sexual function, an important component of quality of life, is gaining increased research and clinical attention in older women with hypertension. To assess the association between systolic blood pressure (SBP) and other variables, and sexual activity and sexual dysfunction in hypertensive women. Baseline analysis of 635 women participants of a larger randomized clinical trial of 9361 men and women. Self-reported sexual activity (yes/no), and sexual function using the Female Sexual Function Inventory (FSFI). 452 participants (71.2%) reported having no sexual activity during the previous 4 weeks. The mean (SD) FSFI score for sexually active participants was 25.3 (6.0), and 52.6% of the sample reported a FSFI score ≤26.55 designating sexual dysfunction. In logistic regression models, SBP was not significantly associated with sexual activity (AOR = 1.002; P > .05). Older age (AOR = 0.95, P sexually active, as was living alone versus living with others (AOR = 0.56, P sexually active (AOR = 1.39; P sexually active participants, SBP was not associated with sexual dysfunction (AOR = 1.01; P > .05). Higher depressive symptoms from the Patient Health Questionnaire-9 (PHQ-9) was associated with higher odds of sexual dysfunction (AOR = 1.24, P sexually active in participants with chronic kidney disease (AOR = 0.33, P sexually active in a sample of middle-aged and older women with hypertension. Increased depressive symptoms and increased physical comorbidities were significantly associated with increased odds of sexual dysfunction. SBP was not significantly associated with sexual activity or sexual dysfunction. Copyright © 2016 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.

  8. A ¤high-fat meal does not activate blood coagulation factor vii in minipigs

    DEFF Research Database (Denmark)

    Olsen, A. K.; Larsen, L. F.; Bladbjerg, E.-M.

    2001-01-01

    tool. We studied postprandial FVII activation in seven non-fasting Göttingen minipigs. Intralipid (4 g/kg) was administered through a gastric tube in two fractions at 9.00 a.m. (one-third of total dose) and 10.30 a.m. (two-thirds of total dose). Blood samples were drawn 0.5 h before (baseline) and 2, 3......It is a matter of debate whether postprandial activation of blood coagulation factor VII (FVII) is associated with an increased risk of thrombosis. To clarify this question, an animal model in which consequences of dietary FVII activation can be studied in a more detailed way would be an important...... to activate blood coagulation FVII in minipigs, the pig is apparently not a relevant model for the study of dietary FVII activation and thrombin generation. Udgivelsesdato: 2001-Mar...

  9. Studies on bactericidal efficacy of pumpkin (Cucurbita moschata Duchesne peel

    Directory of Open Access Journals (Sweden)

    El Zawane Kamarudin

    2014-02-01

    Full Text Available Objective: T o explore the in vitro antibacterial potential of the peel of Cucurbita moschata D uchesne ( tropical pumpkin ( C. moschata against human pathogenic bacteria. Methods: I n the present study, dichloromethane ( DCM , methanol ( MEOH and aqueous extracts of C. moschata peel were examined for in vitro antibacterial potency against eight bacterial strains i.e. Bacillus cereus, Burkholderia cepacia, Escherichia coli, Enterococcus faecalis, Staphyloccocus aureus, Pseudomonas aerugenosa, Vibrio alginolyticus, Vibrio parahaemolyticus using K irby- B auer disk diffusion susceptibility and broth micro-dilution methods. Results: DCM extract of pumpkin peel exhibited the maximum zone of inhibition against Staphyloccocus aureus ( 21 mm whereas aqueous extract of pumpkin peel revealed the least zone of inhibition against Escherichia coli ( 8 mm . MEOH extract gave maximum zone of inhibition against Pseudomonas aerugenosa ( 19 mm . B roth micro-dilution method showed minimum inhibitory concentration for the DCM extract against Burkholderia cepacia at 6 . 25 mg/m L . T he minimum bactericidal concentrations were also determined to know the nature of all extracts. DCM and MEOH extracts exhibited bactericidal nature to all bacterial strains except for the Vibrio alginolyticus. T he minimum bactericidal concentrations values exhibited bactericidal nature ranging from 3 . 12 mg/m L to 100 . 00 mg/m L . T he screening of antimicrobial properties of different extracts of C. moschata peel revealed that the DCM extract possessed good antimicrobial efficacy compared to MEOH and aqueous extracts. Conclusions: P eel of C. moschata possesses antibacterial compounds and could be potential source for a new class of antibiotics.

  10. Null bactericidal effect of ultraviolet radiation emitted by LEDs.

    OpenAIRE

    Francisco Alcántara Muñoz; Rafael Moreno-Rojas; Alicia Moreno Ortega; José Emilio Muñoz Cañete; Rafael Gómez Díaz

    2016-01-01

    This research has aimed to assess the bactericidal effect of ultraviolet light emitted by LEDS on the growth on Petri dishes of microorganisms whose legal limits in foods have been established. An electrically fed apparatus has been designed with precise timing and a camera to prevent light spillage, in which two ultraviolet radiation emission devices were connected by LED technology at different wavelengths: through an array of LEDS emitting at around 350nm, and a single specific...

  11. Bactericidal and cytotoxic effects of hypothiocyanite-hydrogen peroxide mixtures.

    OpenAIRE

    Carlsson, J; Edlund, M B; Hänström, L

    1984-01-01

    Lactoperoxidase catalyzes the oxidation of thiocyanate by hydrogen peroxide into hypothiocyanite, a reaction which can protect bacterial and mammalian cells from killing by hydrogen peroxide. The present study demonstrates, however, that lactoperoxidase in the presence of thiocyanate can actually potentiate the bactericidal and cytotoxic effects of hydrogen peroxide under specific conditions, such as when hydrogen peroxide is present in the reaction mixtures in excess of thiocyanate. The toxi...

  12. Subsets of memory CD4+ T cell and bactericidal antibody response to Neisseria meningitidis serogroup C after immunization of HIV-infected children and adolescents.

    Science.gov (United States)

    Milagres, Lucimar G; Costa, Priscilla R; Silva, Giselle P; Carvalho, Karina I; Pereira-Manfro, Wânia F; Ferreira, Bianca; Barreto, Daniella M; Frota, Ana Cristina C; Hofer, Cristina B; Kallas, Esper G

    2014-01-01

    Meningococcal disease is endemic in Brazil, with periodic outbreaks and case fatality rates reach as high as 18 to 20% of cases. Conjugate vaccines against meningococci are immunogenic in healthy children. However, we have previously shown a poor bactericidal antibody response to a Men C conjugate vaccine in Brazilian HIV-infected children and adolescents after a single vaccine administration. The goal of the present work was to investigate associations between bactericidal antibody response induced by MenC vaccine and the frequency and activation profile (expression of CD38, HLA-DR and CCR5 molecules) of total CD4+ memory T cell sub-populations in HIV-1-infected children and adolescents. Responders to vaccination against MenC had a predominance (about 44%) of CD4+ TINTERMEDIATE subset followed by TTRANSITIONAL memory subset (23 to 26%). Importantly, CD4+ TINT frequency was positively associated with bactericidal antibody response induced by vaccination. The positive correlation persisted despite the observation that the frequency TINT CD38+HLA-DR+ was higher in responders. In contrast, CD4+ TCENTRAL MEMORY (TCM) subset negatively correlated with bactericidal antibodies. In conclusion, these data indicate that less differentiated CD+ T cells, like TCM may be constantly differentiating into intermediate and later differentiated CD4+ T cell subsets. These include CD4 TINT subset which showed a positive association with bactericidal antibodies.

  13. Subsets of memory CD4+ T cell and bactericidal antibody response to Neisseria meningitidis serogroup C after immunization of HIV-infected children and adolescents.

    Directory of Open Access Journals (Sweden)

    Lucimar G Milagres

    Full Text Available Meningococcal disease is endemic in Brazil, with periodic outbreaks and case fatality rates reach as high as 18 to 20% of cases. Conjugate vaccines against meningococci are immunogenic in healthy children. However, we have previously shown a poor bactericidal antibody response to a Men C conjugate vaccine in Brazilian HIV-infected children and adolescents after a single vaccine administration. The goal of the present work was to investigate associations between bactericidal antibody response induced by MenC vaccine and the frequency and activation profile (expression of CD38, HLA-DR and CCR5 molecules of total CD4+ memory T cell sub-populations in HIV-1-infected children and adolescents. Responders to vaccination against MenC had a predominance (about 44% of CD4+ TINTERMEDIATE subset followed by TTRANSITIONAL memory subset (23 to 26%. Importantly, CD4+ TINT frequency was positively associated with bactericidal antibody response induced by vaccination. The positive correlation persisted despite the observation that the frequency TINT CD38+HLA-DR+ was higher in responders. In contrast, CD4+ TCENTRAL MEMORY (TCM subset negatively correlated with bactericidal antibodies. In conclusion, these data indicate that less differentiated CD+ T cells, like TCM may be constantly differentiating into intermediate and later differentiated CD4+ T cell subsets. These include CD4 TINT subset which showed a positive association with bactericidal antibodies.

  14. Effects of Halothane Anesthesia on Blood Cholinesterase Activity in Cats

    Science.gov (United States)

    1989-07-01

    Kirby SEP 07 1989" A.T. TownsendS d 14’ C. D. PopID R.G. Stafford T. H. Harding Sensory Research Division July 1989 Approved for pubic relese ...halothane. Activity of synaptically released acetylcholine (ACh) is terminated by the degradative enzyme acetylcholinesterase (AChE), or true...certainly tremendous interest concerning the role of acetylcholine as a central neurotransmitter and its possible interaction with other neurotransmitter

  15. The bactericidal effect of carbon nanotube/agar composites irradiated with near-infrared light on Streptococcus mutans

    OpenAIRE

    Akasaka, Tsukasa; Matsuoka, Makoto; Hashimoto, Takeshi; Abe, Shigeaki; Uo, Motohiro; Watari, Fumio

    2010-01-01

    Dental caries are mainly associated with oral pathogens, and Streptococcus 2 mutans is a primary cariogenic organism. Many methods have been established to eliminate S. mutans from the oral cavity. This study aimed to evaluate the effect of carbon nanotube (CNT)/agar composites irradiated with near-infrared (NIR) light on S. mutans, as a potential photothermal antimicrobial nanotherapy. A colony-forming unit assay clearly showed that CNT/agar composites attain bactericidal activity after NIR ...

  16. Encapsulation of titanium dioxide nanoparticles in PLA microspheres using supercritical emulsion extraction to produce bactericidal nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Campardelli, R., E-mail: rcampardelli@unisa.it; Della Porta, G. [University of Salerno, Department of Industrial Engineering (Italy); Gomez, V.; Irusta, S. [University of Zaragoza, Aragon Institute of Nanoscience (INA) (Spain); Reverchon, E., E-mail: ereverchon@unisa.it [University of Salerno, Department of Industrial Engineering (Italy); Santamaria, J., E-mail: jesus.santamaria@unizar.es [University of Zaragoza, Aragon Institute of Nanoscience (INA) (Spain)

    2013-10-15

    In this work, PLA microparticles containing TiO{sub 2} (anatase) nanoparticles have been produced using the Continuous Supercritical Emulsion Extraction technique (SEE-C). A stabilized anatase colloidal suspension (15 {+-} 5 nm) in ethanol aqueous solution was obtained by precipitation from solutions of titanium alkoxides and directly used as the water internal phase of a water-in-oil in water double emulsion or suspended as a powder in the organic phase of a solid-in-oil in water emulsion. Micro- (0.9 {+-} 0.5 {mu}m) and submicro-particles (203 {+-} 40 nm) have been produced, with TiO{sub 2} nominal loadings of 1.2, 2.4, and 3.6 wt%. High TiO{sub 2} encapsulation efficiencies up to about 90 % have been obtained. PLA/TiO{sub 2} particles have been characterized by TEM and XPS to investigate the dispersion of the metal oxide in the polymeric matrix. The photo-assisted bactericidal activity of TiO{sub 2}-containing microparticles against a biofilm-forming strain of Staphylococcus aureus was investigated in specific assays under UV light. Pure TiO{sub 2} nanoparticles and PLA/TiO{sub 2} particles showed the same bactericidal activity.

  17. Encapsulation of titanium dioxide nanoparticles in PLA microspheres using supercritical emulsion extraction to produce bactericidal nanocomposites

    Science.gov (United States)

    Campardelli, R.; Della Porta, G.; Gomez, V.; Irusta, S.; Reverchon, E.; Santamaria, J.

    2013-10-01

    In this work, PLA microparticles containing TiO2 (anatase) nanoparticles have been produced using the Continuous Supercritical Emulsion Extraction technique (SEE-C). A stabilized anatase colloidal suspension (15 ± 5 nm) in ethanol aqueous solution was obtained by precipitation from solutions of titanium alkoxides and directly used as the water internal phase of a water-in-oil in water double emulsion or suspended as a powder in the organic phase of a solid-in-oil in water emulsion. Micro- (0.9 ± 0.5 μm) and submicro-particles (203 ± 40 nm) have been produced, with TiO2 nominal loadings of 1.2, 2.4, and 3.6 wt%. High TiO2 encapsulation efficiencies up to about 90 % have been obtained. PLA/TiO2 particles have been characterized by TEM and XPS to investigate the dispersion of the metal oxide in the polymeric matrix. The photo-assisted bactericidal activity of TiO2-containing microparticles against a biofilm-forming strain of Staphylococcus aureus was investigated in specific assays under UV light. Pure TiO2 nanoparticles and PLA/TiO2 particles showed the same bactericidal activity.

  18. Blood Biochemical Reference Intervals for Wild Ornate Box Turtles ( Terrapene ornata) during the Active Season.

    Science.gov (United States)

    Harden, Leigh Anne; Fernandez, Jennifer; Milanovich, Joseph R; Struecker, Brock P; Midway, Stephen R

    2018-03-21

    Blood biochemical and hematology analyses are helpful indicators of the physiologic health of animals, particularly when making conservation and management decisions for threatened species. In this study, we 1) established blood biochemical reference intervals for two populations of threatened, free-ranging ornate box turtles ( Terrapene ornata) in northern Illinois during their active season and 2) examined the effects of individual carapace temperature ( T c ) on blood biochemical variables by using a Bayesian hierarchic framework. Individual blood variables differed throughout the active season (May-September 2015), but there were few distinct patterns in concentrations over time. When controlling for individual variability, blood biochemical variables potassium, sodium, chloride, ionized calcium, hematocrit (percentage of packed cell volume), and osmolality showed no effect of T c (i.e., slope estimates for these variables were not credibly different from zero) and had little individual variation. Glucose and blood urea nitrogen (BUN) were found to have slopes credibly different from zero, with glucose having an estimated positive slope and BUN having an estimated negative slope, suggesting different relationships in response to T c when controlling for individual variability. These physiologic blood data will serve as important baseline reference values for the clinical evaluation of wild ornate box turtles presented for veterinary care or for comparison to other studies of wild populations. Further, this study highlights the importance of considering individual-level effects (e.g., T c ) on physiologic health variables.

  19. Cytidine triphosphate synthase activity and mRNA expression in normal human blood cells

    NARCIS (Netherlands)

    Verschuur, A. C.; van Gennip, A. H.; Muller, E. J.; Voûte, P. A.; Vreken, P.; van Kuilenburg, A. B.

    1999-01-01

    Cytidine triphosphate (CTP) synthase is one of the key enzymes in pyrimidine nucleotide anabolic pathways. The activity of this enzyme is elevated in various malignancies including acute lymphocytic leukemia (ALL). In this study we investigated the activity of CTP synthase in various human blood

  20. Glucose-6-phosphate dehydrogenase activity decreases during storage of leukoreduced red blood cells

    NARCIS (Netherlands)

    Peters, Anna L.; van Bruggen, Robin; de Korte, Dirk; van Noorden, Cornelis J. F.; Vlaar, Alexander P. J.

    2016-01-01

    During storage, the activity of the red blood cell (RBC) antioxidant system decreases. Glucose-6-phosphate dehydrogenase (G6PD) is essential for protection against oxidative stress by producing NADPH. G6PD function of RBC transfusion products is reported to remain stable during storage, but activity

  1. A high fat meal activates blood coagulation factor VII in rats

    DEFF Research Database (Denmark)

    Olsen, Aage K; Bladbjerg, Else M; Hansen, Axel K

    2002-01-01

    In humans, high fat meals cause postprandial activation of blood coagulation factor VII (FVII), but human studies have not provided definite evidence for a prothrombotic effect of dietary FVII activation. An animal model would be an attractive way to pursue this question and therefore we tested...

  2. Effects of dietary fat quality and quantity on postprandial activation of blood coagulation factor VII

    DEFF Research Database (Denmark)

    Larsen, L F; Bladbjerg, E-M; Jespersen, J

    1997-01-01

    Acute elevation of the coagulant activity of blood coagulation factor VII (FVIIc) is observed after consumption of high-fat meals. This elevation is caused by an increase in the concentration of activated FVII (FVIIa). In a randomized crossover study, we investigated whether saturated...

  3. BLOOD EOSINOPHIL NUMBERS AND ACTIVITY DURING 24 HOURS - EFFECTS OF TREATMENT WITH BUDESONIDE AND BAMBUTEROL

    NARCIS (Netherlands)

    WEMPE, JB; TAMMELING, EP; KOETER, GH; HAKANSSON, L; VENGE, P; POSTMA, DS

    1992-01-01

    The effects of the inhaled corticosteroid budesonide and the oral long-acting beta-agonist bambuterol on circadian variation of blood eosinophil numbers, serum levels of eosinophil cationic protein (ECP), serum eosinophil chemotactic activity (ECA), and serum neutrophil chemotactic activity (NCA)

  4. Analysis of elements in human blood of patients with chronic kidney disease using neutron activation analysis

    International Nuclear Information System (INIS)

    Metairon, S.; Zamboni, C.B.; Kovacs, L.; Genezini, F.A.; Santos, N.F.; Vilela, E.C.

    2009-01-01

    Neutron activation analysis has been used to determine Br, Ca, Cl, K, Mg and Na concentrations in whole blood of patients with chronic kidney disease (CKD) as well as in whole blood of normal individuals (control group). The dependence of the elements concentration in function of sex, age, time and type of treatment were investigated. The similarities and differences between healthy individuals and CKD are discussed. (author)

  5. Quantitative evaluation of blood elements by neutron activation analysis in mice immunized with Bothrops snake venoms

    International Nuclear Information System (INIS)

    Zamboni, C.B.; Metairon, S.; Suzuki, M.F.; Furtado, M.F.; Sant'Anna, O.A.; Tambourgi, D.V.

    2009-01-01

    Mice genetically selected for high antibody responsiveness (HIII) were immunized against different Bothrops species snake venoms from distinct region of Brazil. The Neutron Activation Analysis technique was used to evaluate the whole blood concentrations of elements of clinical relevance [Ca, Cl, K, Mg and Na] in order to establish a potential correlation between antibody response and blood constituents after Bothrops venom administration for clinical screening of envenomed patients. (author)

  6. [Microbiological assesssment of efficiency chemothermal disinfection of blood contaminated hospital textiles].

    Science.gov (United States)

    Röhm-Rodowald, Ewa; Jakimiak, Bozenna; Podgórska, Marta; Chojecka, Agnieszka

    2010-01-01

    Thermal disinfection should be applied to laundering procedures of hospital textiles contaminated with blood. Currently, there is an increasing number of hospital textiles composed of cotton-polyester blends that cannot endure high temperatures of thermal disinfection. Besides, decreasing the temperature of chemothermal disinfection enhances the possibility of micro-organisms to survive the laundering procedure. The aim of this study was to prepare a new method for the microbiological evaluation of disinfecting laundering procedures for hospital textiles contaminated with blood. The bactericidal activity of chemical disinfectants for chemothermal disinfection was determined by simulating a laundering procedure for hospital textiles in the laboratory according to procedure of National Institute of Hygiene - DF/05/03. Bioindicators cotton carriers inoculated with Enterococcus faecium were used for determinating the antibacterial effects for hospital textiles contaminated with blood. High concentrations of bovine albumin and/or sheep erythrocytes were used as substrate for simulating human blood. The results showed that the bactericidal activity of chemical disinfectants for chemothermal disinfection hospital textiles in the event of massive organic contamination--heavily soiled with blood, shall be evaluated using carrier test in following conditions: test organism- Enterococcus faecium, interfering substances--6 g/l bovine albumin solution added to preparation.

  7. Serum bactericidal activity against Helicobacter pylori in patients with hypogammaglobulinaemia.

    NARCIS (Netherlands)

    Desar, I.M.E.; Deuren, M. van; Sprong, T.; Jansen, J.B.M.J.; Namavar, F.; Vandenbroucke-Grauls, C.M.; Meer, J.W.M. van der

    2009-01-01

    The two major primary antibody deficiency disorders are X-linked hypogammaglobulinaemia (XLA) and common variable immunodeficiency (CVID). CVID patients have an elevated risk for gastric cancer and extra-nodal marginal zone lymphoma. Both diseases are associated with Helicobacter pylori infection.

  8. Serum bactericidal activity against Helicobacter pylori in patients with hypogammaglobulinaemia

    NARCIS (Netherlands)

    Desar, I. M. E.; van Deuren, M.; Sprong, T.; Jansen, J. B. M. J.; Namavar, F.; Vandenbroucke-Grauls, C. M.; van der Meer, J. W. M.

    2009-01-01

    The two major primary antibody deficiency disorders are X-linked hypogammaglobulinaemia (XLA) and common variable immunodeficiency (CVID). CVID patients have an elevated risk for gastric cancer and extra-nodal marginal zone lymphoma. Both diseases are associated with Helicobacter pylori infection.

  9. Early bactericidal activity of ethambutol, pyrazinamide and the fixed ...

    African Journals Online (AJOL)

    Research Council. The authors thank the Medical. Superintendent of Tygerberg Hospital for permission to publish and for considerable help in carrying out the study, Professor. Stephan Maritz for assistance with the statistical analysis,. Amour Venter for excellent technical assistance, and Professor. H. J. Koornhof for critical ...

  10. Lipopolysaccharide enhances bactericidal activity in Dictyostelium discoideum cells

    OpenAIRE

    Walk, Alexander; Callahan, Jennifer; Srisawangvong, Pat; Leuschner, Jessica; Samaroo, Dave; Cassilly, Daniel; Snyder, Michelle L.D.

    2011-01-01

    Innate immune cells respond to invading microbes upon detection of pathogen-associated molecular patterns (PAMPS). PAMP-recognition machinery is evolutionarily conserved, allowing for characterization in model organisms. The model organism Dictyostelium discoideum can exist as single-celled amoebae, which phagocytize bacteria for nutrients. Although D. discoideum is used extensively to study phagocytosis, it has not been determined if D. discoideum detects bacterial PAMPs using pattern-recogn...

  11. Construction of a genome-scale metabolic network of the plant pathogen Pectobacterium carotovorum provides new strategies for bactericide discovery.

    Science.gov (United States)

    Wang, Cheng; Deng, Zhi-Luo; Xie, Zhi-Ming; Chu, Xin-Yi; Chang, Ji-Wei; Kong, De-Xin; Li, Bao-Ju; Zhang, Hong-Yu; Chen, Ling-Ling

    2015-01-30

    We reconstructed the first genome-scale metabolic network of the plant pathogen Pectobacterium carotovorum subsp. carotovorum PC1 based on its genomic sequence, annotation, and physiological data. Metabolic characteristics were analyzed using flux balance analysis (FBA), and the results were afterwards validated by phenotype microarray (PM) experiments. The reconstructed genome-scale metabolic model, iPC1209, contains 2235 reactions, 1113 metabolites and 1209 genes. We identified 19 potential bactericide targets through a comprehensive in silico gene-deletion study. Next, we performed virtual screening to identify candidate inhibitors for an important potential drug target, alkaline phosphatase, and experimentally verified that three lead compounds were able to inhibit both bacterial cell viability and the activity of alkaline phosphatase in vitro. This study illustrates a new strategy for the discovery of agricultural bactericides. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  12. Stability of cytokines, chemokines and soluble activation markers in unprocessed blood stored under different conditions.

    Science.gov (United States)

    Aziz, Najib; Detels, Roger; Quint, Joshua J; Li, Qian; Gjertson, David; Butch, Anthony W

    2016-08-01

    Biomarkers such as cytokines, chemokines, and soluble activation markers can be unstable when processing of blood is delayed. The stability of various biomarkers in serum and plasma was investigated when unprocessed blood samples were stored for up to 24h at room and refrigerator temperature. Blood was collected from 16 healthy volunteers. Unprocessed serum, EDTA and heparinized blood was stored at room (20-25°C) and refrigerator temperature (4-8°C) for 0.5, 2, 4, 6, 8, and 24h after collection before centrifugation and separation of serum and plasma. Samples were batch tested for various biomarkers using commercially available immunoassays. Statistically significant changes were determined using the generalized estimating equation. IFN-γ, sIL-2Rα, sTNF-RII and β2-microglobulin were stable in unprocessed serum, EDTA and heparinized blood samples stored at either room or refrigerator temperature for up to 24h. IL-6, TNF-α, MIP-1β and RANTES were unstable in heparinized blood at room temperature; TNF-α, and MIP-1β were unstable in unprocessed serum at room temperature; IL-12 was unstable in unprocessed serum at refrigerator temperature; and neopterin was unstable in unprocessed EDTA blood at room temperature. IL-1ra was stable only in unprocessed serum at room temperature. All the biomarkers studied, with the exception of IL-1ra, were stable in unprocessed EDTA blood stored at refrigerator temperature for 24h. This indicates that blood for these biomarkers should be collected in EDTA and if delays in processing are anticipated the unseparated blood should be stored at refrigerator temperature until processing. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Rapid bactericidal action of alpha-mangostin against MRSA as an outcome of membrane targeting.

    Science.gov (United States)

    Koh, Jun-Jie; Qiu, Shengxiang; Zou, Hanxun; Lakshminarayanan, Rajamani; Li, Jianguo; Zhou, Xiaojun; Tang, Charles; Saraswathi, Padmanabhan; Verma, Chandra; Tan, Donald T H; Tan, Ai Ling; Liu, Shouping; Beuerman, Roger W

    2013-02-01

    The emergence of methicillin-resistant Staphylococcus aureus (MRSA) has created the need for better therapeutic options. In this study, five natural xanthones were extracted and purified from the fruit hull of Garcinia mangostana and their antimicrobial properties were investigated. α-Mangostin was identified as the most potent among them against Gram-positive pathogens (MIC=0.78-1.56 μg/mL) which included two MRSA isolates. α-Mangostin also exhibited rapid in vitro bactericidal activity (3-log reduction within 5 min). In a multistep (20 passage) resistance selection study using a MRSA isolated from the eye, no resistance against α-mangostin in the strains tested was observed. Biophysical studies using fluorescence probes for membrane potential and permeability, calcein encapsulated large unilamellar vesicles and scanning electron microscopy showed that α-mangostin rapidly disrupted the integrity of the cytoplasmic membrane leading to loss of intracellular components in a concentration-dependent manner. Molecular dynamic simulations revealed that isoprenyl groups were important to reduce the free energy for the burial of the hydrophobic phenyl ring of α-mangostin into the lipid bilayer of the membrane resulting in membrane breakdown and increased permeability. Thus, we suggest that direct interactions of α-mangostin with the bacterial membrane are responsible for the rapid concentration-dependent membrane disruption and bactericidal action. Copyright © 2012 Elsevier B.V. All rights reserved.

  14. Effect of exercise on erythrocyte count and blood activity concentration after /sup 99m/Tc in vivo red blood cell labeling

    International Nuclear Information System (INIS)

    Konstam, M.A.; Tu'meh, S.; Wynne, J.; Beck, J.R.; Kozlowski, J.; Holman, B.L.

    1982-01-01

    We studied the effect of exercise on blood radiotracer concentration after /sup 99m/Tc in vivo red blood cell labeling. After red blood cell labeling, 13 subjects underwent maximal supine bicycle exercise. Radioactivity, analyzed with a well counter, was measured in heparinized venous blood samples drawn at rest and during peak exercise. Changes in activity were compared with changes in erythrocyte count. Activity and erythrocyte counts increased during exercise in all 13 subjects. Percent increase in activity correlated with percent increase in erythrocyte count (r . -0.78), but did not correlate with either duration of exercise or maximal heart rate. Twenty minutes after termination of exercise, activity and erythrocyte count had decreased from peak exercise values but remained higher than preexercise values. In nine nonexercised control subjects, samples drawn 20 minutes apart showed no change in activity or in erythrocyte count. We conclude that exercise increases blood activity, primarily because of an increase in erythrocyte count. During radionuclide ventriculography, blood activity must be measured before and after any intervention, particularly exercise, before a change in left ventricular activity can be attributed to a change in left ventricular volume

  15. Analysis by confocal laser scanning microscopy of the MDPB bactericidal effect on S. mutans biofilm CLSM analysis of MDPB bactericidal effect on biofilm

    Directory of Open Access Journals (Sweden)

    Fabíola Galbiatti de Carvalho

    2012-10-01

    Full Text Available Since bacteria remain in the dentin following caries removal, restorative materials with antibacterial properties are desirable to help maintaining the residual microorganisms inactive. The adhesive system Clearfil Protect Bond (PB contains the antibacterial monomer 12-methacryloyloxydodecylpyridinium bromide (MDPB in its primer, which has shown antimicrobial activity. However, its bactericidal effect against biofilm on the dentin has been little investigated. Objective: The aim of this study was to analyze by confocal laser scanning microscopy (CLSM and viable bacteria counting (CFU the MDPB bactericidal effect against S. mutans biofilm on the dentin surface. Material and methods: Bovine dentin surfaces were obtained and subjected to S. mutans biofilm formation in BHI broth supplemented with 1% (w/v sucrose for 18 h. Samples were divided into three groups, according to the primer application (n=3: Clearfil Protect Bond (PB, Clearfil SE Bond, which does not contain MDPB, (SE and saline (control group. After the biofilm formation, Live/ Dead stain was applied directly to the surface of each sample. Next, 10 µL of each primer were applied on the samples during 590 s for the real-time CLSM analysis. The experiment was conducted in triplicate. The primers and saline were also applied on the other dentin samples during 20, 90, 300 and 590 s (n=9 for each group and period evaluated and the CFU were assessed by colonies counting. Results: The results of the CLSM showed that with the Se application, although non-viable bacteria were detected at 20 s, there was no increase in their count during 590 s. In contrast, after the PB application there was a gradual increase of non-viable bacteria over 590 s. Conclusions: The quantitative analysis demonstrated a significant decrease of S. mutans CFU at 90 s PB exposure and only after 300 s of Se application. Protect Bond showed an earlier antibacterial effect than Se Bond.

  16. Red blood cell glutathione peroxidase activity in female nulligravid and pregnant rats

    Directory of Open Access Journals (Sweden)

    Martino Guglielmo

    2009-01-01

    Full Text Available Abstract Background The alterations of the glutathione peroxidase enzyme complex system occur in physiological conditions such as aging and oxidative stress consequent to strenuous exercise. Methods Authors optimize the spectrophotometric method to measure glutathione peroxidase activity in rat red blood cell membranes. Results The optimization, when applied to age paired rats, both nulligravid and pregnant, shows that pregnancy induces, at seventeen d of pregnancy, an increase of both reactive oxygen substance concentration in red blood cells and membrane glutathione peroxidase activity. Conclusion The glutathione peroxidase increase in erythrocyte membranes is induced by systemic oxidative stress long lasting rat pregnancy.

  17. Determination of mercury in human serum and packed blood cells by neutron activation analysis

    International Nuclear Information System (INIS)

    Versieck, J.; Vanballenberghe, L.; Wittoek, A.; Vermeir, G.; Vandecasteele, C.

    1990-01-01

    A method is described for the determination of mercury in human blood serum and packed blood cells employing neutron activation analysis. Great attention was devoted to the collection and manipulation of the samples. The accuracy and precision of the method were tested by analyzing biological reference materials and by comparing the concentrations measured in a number of serum samples to those obtained by another, independent technique (cold vapor atomic absorption spectrometry) in the same samples. The article reports the levels measured in blood serum and packed blood cells samples from 15 adult volunteers, as well as the figures determined in a open-quotes second-generationclose quotes biological reference material (freeze-dried human serum), prepared and conditioned at the University of Ghent

  18. An Engineered R-Type Pyocin Is a Highly Specific and Sensitive Bactericidal Agent for the Food-Borne Pathogen Escherichia coli O157:H7

    Science.gov (United States)

    Some strains of Pseudomonas aeruginosa produce R-type pyocins, which are high molecular weight phage tail-like protein complexes that have bactericidal activity against other Pseudomonas strains. These particles recognize and bind to bacterial surface structures via tail fibers; their primary spectr...

  19. Sex and storage affect cholinesterase activity in blood plasma of Japanese quail

    Science.gov (United States)

    Hill, E.F.

    1989-01-01

    Freezing at -25?C had confounding effects on cholinesterase (ChE) activity in blood plasma from breeding female quail, but did not affect ChE activity in plasma from males. Plasma ChE activity of control females increased consistently during 28 days of storage while both carbamate- and cidrotophos-inhibited ChE decreased. Refrigeration of plasma at 4?C for 2 days had little effect of ChE activity. Plasma ChE activity was averaged about 34% higher in breeding males than in females. Extreme caution should be exercised in use of blood plasma for evaluation of anti ChE exposure in free-living birds.

  20. Blood phagocyte activity after race training sessions in Thoroughbred and Arabian horses.

    Science.gov (United States)

    Cywinska, Anna; Szarska, Ewa; Degorski, Andrzej; Guzera, Maciej; Gorecka, Renata; Strzelec, Katarzyna; Kowalik, Sylwester; Schollenberger, Antoni; Winnicka, Anna

    2013-10-01

    Intensive exercise and exertion during competition promote many changes that may result in the impairment of immunity and increased susceptibility to infections. The aim of this study was to evaluate the activity of "the first line of defense": neutrophils and monocytes in racing Thoroughbred and Arabian horses after routine training sessions. Twenty-three (12 Thoroughbred and 11 Arabian) horses were examined. Routine haematological (number of red blood cells - RBC, haemoglobin concentration - HGB, haematocrit - HCT, total number of white blood cells - WBC), biochemical (creatine phosphokinase activity - CPK and total protein concentration - TP) parameters, cortisol concentration as well as phagocytic and oxidative burst activity of neutrophils and monocytes were determined. The values of basic parameters and the activity of phagocytes differed between breeds and distinct patterns of exercise-induced changes were observed. The training sessions did not produce the decrease in phagocyte activity that might lead to the suppression of immunity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Impact of blood processing variations on Natural Killer cell frequency, activation, chemokine receptor expression and function

    Science.gov (United States)

    Naranbhai, Vivek; Bartman, Pat; Ndlovu, Dudu; Ramkalawon, Pamela; Ndung’u, Thumbi; Wilson, Douglas; Altfeld, Marcus; Carr, William H

    2011-01-01

    Understanding the role of natural killer (NK) cells in human disease pathogenesis is crucial and necessitates study of patient samples directly ex vivo. Manipulation of whole blood by density gradient centrifugation or delays in sample processing due to shipping, however, may lead to artifactual changes in immune response measures. Here, we assessed the impact of density gradient centrifugation and delayed processing of both whole blood and peripheral blood mononuclear cells (PBMC) at multiple timepoints (2–24 hrs) on flow cytometric measures of NK cell frequency, activation status, chemokine receptor expression, and effector functions. We found that density gradient centrifugation activated NK cells and modified chemokine receptor expression. Delays in processing beyond 8 hours activated NK cells in PBMC but not in whole blood. Likewise, processing delays decreased chemokine receptor (CCR4 and CCR7) expression in both PBMC and whole blood. Finally, delays in processing PBMC were associated with a decreased ability of NK cells to degranulate (as measured by CD107a expression) or secrete cytokines (IFN-γ and TNF-α). In summary, our findings suggest that density gradient centrifugation and delayed processing of PBMC can alter measures of clinically relevant NK cell characteristics including effector functions; and therefore should be taken into account in designing clinical research studies. PMID:21255578

  2. Morphological bactericidal fast-acting effects of peracetic acid, a high-level disinfectant, against Staphylococcus aureus and Pseudomonas aeruginosa biofilms in tubing

    Directory of Open Access Journals (Sweden)

    T. Chino

    2017-12-01

    Full Text Available Abstract Background The bactericidal effect of disinfectants against biofilms is essential to reduce potential endoscopy-related infections caused by contamination. Here, we investigated the bactericidal effect of a high-level disinfectant, peracetic acid (PAA, against Staphylococcus aureus and Pseudomonas aeruginosa biofilm models in vitro. Methods S. aureus and P. aeruginosa biofilms were cultured at 35 °C for 7 days with catheter tubes. The following high-level disinfectants (HLDs were tested: 0.3% PAA, 0.55% ortho-phthalaldehyde (OPA, and 2.0% alkaline-buffered glutaraldehyde (GA. Biofilms were exposed to these agents for 1–60 min and observed after 5 min and 30 min by transmission and scanning electron microscopy. A Student’s t test was performed to compare the exposure time required for bactericidal effectiveness of the disinfectants. Results PAA and GA were active within 1 min and 5 min, respectively, against S. aureus and P. aeruginosa biofilms. OPA took longer than 10 min and 30 min to act against S. aureus and P. aeruginosa biofilms, respectively (p < 0.01. Treatment with PAA elicited changes in cell shape after 5 min and structural damage after 30 min. Conclusions Amongst the HLDs investigated, PAA elicited the most rapid bactericidal effects against both biofilms. Additionally, treatment with PAA induced morphological alterations in the in vitro biofilm models, suggesting that PAA exerts fast-acting bactericidal effects against biofilms associated with endoscopy-related infections. These findings indicate that the exposure time for bactericidal effectiveness of HLDs for endoscope reprocessing in healthcare settings should be reconsidered.

  3. Amiloride lowers blood pressure and attenuates urine plasminogen activation in patients with treatment-resistant hypertension

    DEFF Research Database (Denmark)

    Stolzenburg Oxlund, Christina; Buhl, Kristian Bergholt; Jacobsen, Ib A

    2014-01-01

    In conditions with albuminuria, plasminogen is aberrantly filtered across the glomerular barrier and activated along the tubular system to plasmin. In the collecting duct, plasmin activates epithelial sodium channels (ENaC) proteolytically. Hyperactivity of ENaC could link microalbuminuria....../proteinuria to resistant hypertension. Amiloride, an ENaC inhibitor, inhibits urokinase-type plasminogen activator. We hypothesized that amiloride (1) reduces blood pressure (BP); (2) attenuates plasminogen-to-plasmin activation; and (3) inhibits urine urokinase-type plasminogen activator in patients with resistant...

  4. Low catalase activity in blood is associated with the diabetes caused by alloxan.

    Science.gov (United States)

    Takemoto, Kazunori; Tanaka, Miho; Iwata, Hiroshi; Nishihara, Ryou; Ishihara, Kohji; Wang, Da-Hong; Ogino, Keiki; Taniuchi, Koji; Masuoka, Noriyoshi

    2009-09-01

    Hydrogen peroxide is enzymatically processed by catalase, and catalase deficiency in blood is known as acatalasemia. We examined whether low catalase activity is a risk factor for diabetes mellitus. Blood glucose, insulin and glucose tolerance test were examined in acatalasemic and normal mice under non-stress and oxidative stress conditions. Alloxan administration was used as oxidative stress. Alloxan, which was a drug that caused diabetes mellitus, mostly generated hydrogen peroxide by the reaction of alloxan and reduced glutathione, in vitro. Incidence of hyperglycemia in alloxan-untreated acatalasemic mice was as low as that in the normal mice. However, the incidence of acatalasemia mice treated with alloxan was higher than that in normal mice, and the number of pancreatic beta-cells in the acatalasemic mice was less than that in normal mice. These results indicate that low catalase activity in the blood is associated with the diabetes mellitus caused by alloxan administration.

  5. Inhibition of IL-1 activity induced with allogeneic transfusion of UV-irradiated blood

    International Nuclear Information System (INIS)

    Horvat, B.; Poljak-Blazi, M.; Hadija, M.

    1991-01-01

    Treatment with UV-irradiated donor-specific blood transfusion is known to induce specific unresponsiveness in recipient animals and prolong allograft survival. Mixed lymphocyte response in transfused mice was decreased towards spleen cells of the blood donor strain, but was not altered to third-party cells. Sera from treated mice showed significantly lower interleukin-1 (IL-1) activity, which was increased with higher dilutions of sera, indicating the presence of IL-1 inhibitor. Furthermore, sera decreased rIL-1-induced cell proliferation in dose-dependent manner, while the response to rIL-2 neither depended on the concentration of sera, nor differed between non-treated controls and treated mice. These results indicate that UV-irradiated allogeneic blood transfusion could induce an inhibitor, specifically directed to IL-1 activity, which may be involved in the generation of immunological unresponsiveness in treated animals. (author)

  6. The location of splenic NKT cells favours their rapid activation by blood-borne antigen.

    Science.gov (United States)

    Barral, Patricia; Sánchez-Niño, María Dolores; van Rooijen, Nico; Cerundolo, Vincenzo; Batista, Facundo D

    2012-05-16

    Natural killer T (NKT) cells play an important role in mounting protective responses to blood-borne infections. However, though the spleen is the largest blood filter in the body, the distribution and dynamics of NKT cells within this organ are not well characterized. Here we show that the majority of NKT cells patrol around the marginal zone (MZ) and red pulp (RP) of the spleen. In response to lipid antigen, these NKT cells become arrested and rapidly produce cytokines, while the small proportion of NKT cells located in the white pulp (WP) exhibit limited activation. Importantly, disruption of the splenic MZ by chemical or genetic approaches results in a severe reduction in NKT cell activation indicating the need of cooperation between both MZ macrophages and dendritic cells for efficient NKT cell responses. Thus, the location of splenic NKT cells in the MZ and RP facilitates their access to blood-borne antigen and enables the rapid initiation of protective immune responses.

  7. Survival and function of phagocytes in blood culture media

    DEFF Research Database (Denmark)

    Fischer, T K; Prag, J; Kharazmi, A

    1999-01-01

    The survival and function of human phagocytes in sterile aerobic and anaerobic blood culture media were investigated using neutrophil morphology, white blood cell count in a haemoanalyser, flow cytometry, oxidative burst response, and bactericidal effect in Colorbact and Septi-Chek blood culture...

  8. Use of blood-pool imaging in evaluation of diffuse activity patterns in technetium-99m pyrophosphate myocardial scintigraphy.

    Science.gov (United States)

    Cowley, M J; Mantle, J A; Rogers, W J; Russell, R O; Rackley, C E; Logic, J R

    1979-06-01

    It has been suggested that diffuse Tc-99m pyrophosphate precordial activity may be due to persistent blood-pool activity in routine delayed views during myocardial imaging. To answer this question, we reviewed myocardial scintigrams recorded 60--90 min following the injection of 12--15 mCi of Tc-99m pyrophosphate for the presence of diffuse precordial activity, and compared these with early images of the blood pool in 265 patients. Diffuse activity in the delayed images was identified in 48 patients: in 20 with acute myocardial infarction and in 28 with no evidence of it. Comparison of these routine delayed images with early views of the blood pool revealed two types of patterns. In patients with acute infarction, 95% had delayed images that were distinguishable from blood pool either because the activity was smaller than the early blood pool, or by the presence of localized activity superimposed on diffuse activity identical to blood pool. In those without infarction, 93% had activity distribution in routine delayed views matching that in the early blood-pool images. The usefulness of the diffuse TcPPi precordial activity in myocardial infarction is improved when early blood-pool imaging is used to exclude persistence of blood-pool activity as its cause. Moreover, it does not require additional amounts of radioactivity nor complex computer processing, a feature that may be of value in the community hospital using the technique to "rule out" infarction 24--72 hr after onset of suggestive symptoms.

  9. Use of blood-pool imaging in evaluation of diffuse activity patterns in technetium-99m pyrophosphate myocardial scintigraphy

    International Nuclear Information System (INIS)

    Cowley, M.J.; Mantle, J.A.; Rogers, W.J.; Russell, R.O. Jr.; Rackley, C.E.; Logic, J.R.

    1979-01-01

    It has been suggested that diffuse 99m Tc pyrophosphate precordial activity may be due to persistent blood-pool activity in routine delayed views during myocardial imaging. To answer this question, we reviewed myocardial scintigrams recorded 60 to 90 min following the injection of 12 to 15 mCi of 99m Tc pyrophosphate for the presence of diffuse precordial activity, and compared these with early images of the blood pool in 265 patients. Diffuse activity in the delayed images was identified in 48 patients: in 20 with acute myocardial infarction and in 28 with no evidence of it. Comparison of these routine delayed images with early views of the blood pool revealed two types of patterns. In patients with acute infarction, 95% had delayed images that were distinguishable from blood pool either because the activity was smaller than the early blood pool, or by the presence of localized activity superimposed on diffuse activity identical to blood pool. In those without infarction, 93% had activity distribution in routine delayed views matching that in the early blood-pool images. The usefulness of the diffuse TcPPi precordial activity in myocardial infarction is improved when early blood-pool imaging is used to exclude persistence of blood-pool activity as its cause. Moreover, it does not require additional amounts of radioactivity nor complex computer processing, a feature that may be of value in the community hospital using the technique to rule out infarction 24 to 72 hr after onset of suggestive symptoms

  10. Synergistic antibiotic effect of looped antimicrobial peptide CLP-19 with bactericidal and bacteriostatic agents.

    Science.gov (United States)

    Li, Di; Yang, Ya; Tian, Zhiqiang; Lv, Jun; Sun, Fengjun; Wang, Qian; Liu, Yao; Xia, Peiyuan

    2017-08-22

    The treatment of drug-resistant infections is complicated and the alarming rise in infectious diseases poses a unique challenge for development of effective therapeutic strategies. Antibiotic-induced liberation of the bacterial endotoxin lipopolysaccharide (LPS) may have immediate adverse effects promoting septic shock in patients. In the present study, we first confirmed our previous finding that looped antimicrobial peptide CLP-19 exerts non-specific direct antibacterial activity with no toxic to mammalian cells and second revealed that CLP-19 has synergistic effect to enhance the antibacterial activities of other conventional bactericidal (ampicillin and ceftazidime) and bacteriostatic (erythromycin and levofloxacin) agents. Third, the underlying mechanism of antibiotic effect was likely associated with stimulation of hydroxyl radical generation. Lastly, CLP-19 was shown to effectively reduce the antibiotic-induced liberation of LPS, through direct neutralization of the LPS. Thus, CLP-19 is a potential therapeutic agent for combinatorial antibiotic therapy.

  11. Effects of ABO/Rh blood groups, G-6-P-D enzyme activity and ...

    African Journals Online (AJOL)

    The main objective was to investigate the effects of ABO/Rh blood groups, haemoglobin genotype and G-6-P-D enzyme activity on malaria. The study was carried out in Buea, South West Province, Cameroon. Subjects consulting at health care facilities in Buea were randomly recruited into the study. A total of 121 febrile ...

  12. NOS3 Variants, Physical Activity, and Blood Pressure in the European Youth Heart Study

    DEFF Research Database (Denmark)

    Grøntved, Anders; Andersen, Lars Bo; Franks, Paul W

    2011-01-01

    BackgroundIn this study, we examined the influence of genetic variation in NOS3 on resting blood pressure (BP) in children and adolescents from the European Youth Heart Study (EYHS). Because the NOS3 gene expression is altered by physical activity (PA), we also tested for interaction between...

  13. Proteolytic activity of IgGs from blood serum of wistar rats at experimental rheumatoid arthritis

    Directory of Open Access Journals (Sweden)

    Yu. Ya. Kit

    2014-10-01

    Full Text Available The aim of this work was to study the proteolytic activity of IgGs purified from blood serum of Wistar rats at experimental rheumatoid arthritis (ERA induced by an injection of bovine collagen of type II. Twenty rats were immunized with a preparation of bovine collagen II (Sigma-Aldrich, USA in the presence of complete Freund’s adjuvant. ERA development was determined by inflammation in limbs of treated animals. IgG preparations were isolated from blood serum of immunized and non-immunized animals by precipitation of antibodies with 33% ammonium sulfate followed by chromatography on the Protein G-Sepharose column. Human histone H1, bovine collagen II, calf thymus histones, myelin basic protein (MBP, bovine serum albumin (BSA, and bovine casein were used as substrates of the proteolytic activity of IgGs. It was found that IgG preparations from blood serum of rats with ERA were capable of cleaving histone H1 and MBP, however, they were catalytically inactive towards collagen II, casein, BSA, and core histones. IgGs from blood serum of non-immunized rats were proteolytically inactive towards all used protein substrates. Thus, we demonstrated that immunization of rats with bovine collagen II induced IgG-antibodies possessing the proteolytic activity towards histone H1 and MBP. This activity might be associated with the development of inflammatory processes in the immunized rats.

  14. A Kinesthetic Activity Using LEGO Bricks and Buckets for Illustrating the Regulation of Blood Sugar

    Science.gov (United States)

    Urschler, Margaret; Meidl, Katherine; Browning, Samantha; Khan, Basima; Milanick, Mark

    2015-01-01

    This article describes how, when first faced with understanding blood sugar regulation, students often resort to simple memorization.Many students would like to get more involved with the conceptual framework but do not know how to start. The authors have developed an activity based on the Modell approach, a "view from the inside." This…

  15. Radiochemistry helping the community: manganese determination in blood serum by neutronic activation

    International Nuclear Information System (INIS)

    Menezes, Maria Angela B.C.; Kastner, Sonia M.S.; Sabino, Claudia V.S.; Alvarenga, Moema G.

    1995-01-01

    This paper describes the participation of radiochemistry during the diagnosis and the actions to minimize the contamination of workers and people that were living surrounding the industry, by manganese dusts, analysing blood serum samples using neutron activation analysis technique. This is the nuclear technology as a tool to help the community. (author). 4 refs., 1 tab

  16. Human Blood Feeding Activity of Female Hybrids between Culex pipiens pipiens and Culex pipiens quinquefasciatus(Diptera: Culicidae)

    OpenAIRE

    Yoshii, Manabu; Mine, Mariko; Kurokawa, Kenji; Oda, Tsutomu; Kato, Katsutomo; Ogawa, Yasunori; Eshita, Yuuki; Uchida, Keikichi

    2007-01-01

    Human blood feeding activity was examined in females of hybrids between Culex pipiens pipiens and Culex pipiens quinquefasciatus during long photoperiod at 25℃. Blood feeding rates of hybrids were lower than in Culex pipiens quinquefasciatus and Culex pipiens pallens, and higher than in Culex pipiens pipiens, because no females fed on human blood in Culex pipiens pipiens.

  17. Effect of photoperiod on blood feeding activity of female hybrids between Culex pipiens pipiens and Culex pipiens quinquefasciatus (Diptera: Culicidae)

    OpenAIRE

    Kurokawa, Kenji; Yoshii, Manabu; Oda, Tsutomu; Kato, Katsutomo; Uchida, Keikichi; Eshita, Yuki; Tahara, Hiroyuki; Mine, Mariko; Ogawa, Yasunori

    2004-01-01

    Blood feeding activity was examined in females of hybrids (F1) between Culex pipiens pipiens and Culex pipiens quinquefasciatus in long and short photoperiods at 2l℃ to examine the effect of photoperiod on blood feeding rate. Blood feeding rates (F1) were lower in short photoperiods than in long photoperiods. From this, it seems that the hybrids show diapause.

  18. [Analysis of bactericidal material generated by electrical devices advertising bactericidal ability against bacteria on the agar gel plates].

    Science.gov (United States)

    Nishimura, Hidekazu

    2012-11-01

    Several Japanese companies sell electrical devices advertised as effective in inactivating viruses and killing bacteria by releasing special materials, e.g., Plasmacluster ions, Nanoe particle and minus ions, into the air. These companies claim that their devices killed bacteria on plates in their own experiments. We tested device effectiveness using the same experiments from the Plasmacluster ioniser SHARP Co., Japan, the Nanoe generator Panasonic Co., Japan, and the Vion KING JIM Co., Japan, to test their advertising claims. Bactericidal ability on agar plate was tested, using Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus cereus, and Enterococcus faecalis as follows: the medium containing a certain amount of each bacterium was put onto an agar plate and smeared. Plates were kept in a closed chamber (inner volume 14.4 m3) or a glove box (inner volume 0.2 m), with one of the devices run for 2 hours. Plates not exposed to any device were used as controls. Each plate was retrieved and put in an incubator to count the number of bacterial colonies formed on the plate. There was no significant difference in the number of colonies on plates exposed to devices compared to control, in the number for all devices, or in all bacteria tested in experiments in the 14.4 m3 chamber. These results strongly suggest that these devices have almost no bactericidal effect, at least in space exceeding this volume. Colony formation was suppressed in the glove box in all devices and in all bacteria tested except P. aeruginosa, although the degree of suppression differed among experiments. The colony formation suppression mechanism was analyzed, and indicated that:colony formation did not change even after the removal of Plasmacluster ions, Nanoe particles, or negative ions from the air, while colony formation was decreased drastically by the removal of ozone from space, which was revealed to be generated inevitably during device operation. These results strongly suggest that the

  19. Influence of adrenaline on the activity of succinate dehydrogenase in peripheral blood lymphocytes of irradiated rats

    International Nuclear Information System (INIS)

    Koroleva, L.V.; Vasin, M.V.

    1988-01-01

    In experiments with albino mongrel female rats, the influence of adrenaline on succinate dehydrogenase (SDG) activity in the peripheral blood lymphocytes of irradiated and intact animals has been investigated. Two minutes after the intraperitoneal administration of adrenaline (1 mg/kg) to intact rats SDG activity sharply rises and 3-4 min it drastically falls. In 6 to 8 min the second peak in the enzyme activity is registered. Twenty minutes after irradiation of rats in the crano-caudal direction with a dose of 75 Gy delivered to head, the reaction to adrenaline, manifested by the rise in SDG activity, is absent

  20. Anopheles midgut epithelium evades human complement activity by capturing factor H from the blood meal.

    Science.gov (United States)

    Khattab, Ayman; Barroso, Marta; Miettinen, Tiera; Meri, Seppo

    2015-02-01

    Hematophagous vectors strictly require ingesting blood from their hosts to complete their life cycles. Exposure of the alimentary canal of these vectors to the host immune effectors necessitates efficient counteractive measures by hematophagous vectors. The Anopheles mosquito transmitting the malaria parasite is an example of hematophagous vectors that within seconds can ingest human blood double its weight. The innate immune defense mechanisms, like the complement system, in the human blood should thereby immediately react against foreign cells in the mosquito midgut. A prerequisite for complement activation is that the target cells lack complement regulators on their surfaces. In this work, we analyzed whether human complement is active in the mosquito midgut, and how the mosquito midgut cells protect themselves against complement attack. We found that complement remained active for a considerable time and was able to kill microbes within the mosquito midgut. However, the Anopheles mosquito midgut cells were not injured. These cells were found to protect themselves by capturing factor H, the main soluble inhibitor of the alternative complement pathway. Factor H inhibited complement on the midgut cells by promoting inactivation of C3b to iC3b and preventing the activity of the alternative pathway amplification C3 convertase enzyme. An interference of the FH regulatory activity by monoclonal antibodies, carried to the midgut via blood, resulted in increased mosquito mortality and reduced fecundity. By using a ligand blotting assay, a putative mosquito midgut FH receptor could be detected. Thereby, we have identified a novel mechanism whereby mosquitoes can tolerate human blood.

  1. Anopheles midgut epithelium evades human complement activity by capturing factor H from the blood meal.

    Directory of Open Access Journals (Sweden)

    Ayman Khattab

    2015-02-01

    Full Text Available Hematophagous vectors strictly require ingesting blood from their hosts to complete their life cycles. Exposure of the alimentary canal of these vectors to the host immune effectors necessitates efficient counteractive measures by hematophagous vectors. The Anopheles mosquito transmitting the malaria parasite is an example of hematophagous vectors that within seconds can ingest human blood double its weight. The innate immune defense mechanisms, like the complement system, in the human blood should thereby immediately react against foreign cells in the mosquito midgut. A prerequisite for complement activation is that the target cells lack complement regulators on their surfaces. In this work, we analyzed whether human complement is active in the mosquito midgut, and how the mosquito midgut cells protect themselves against complement attack. We found that complement remained active for a considerable time and was able to kill microbes within the mosquito midgut. However, the Anopheles mosquito midgut cells were not injured. These cells were found to protect themselves by capturing factor H, the main soluble inhibitor of the alternative complement pathway. Factor H inhibited complement on the midgut cells by promoting inactivation of C3b to iC3b and preventing the activity of the alternative pathway amplification C3 convertase enzyme. An interference of the FH regulatory activity by monoclonal antibodies, carried to the midgut via blood, resulted in increased mosquito mortality and reduced fecundity. By using a ligand blotting assay, a putative mosquito midgut FH receptor could be detected. Thereby, we have identified a novel mechanism whereby mosquitoes can tolerate human blood.

  2. Enhanced Activities of Blood Thiamine Diphosphatase and Monophosphatase in Alzheimer's Disease.

    Directory of Open Access Journals (Sweden)

    Xiaoli Pan

    Full Text Available Thiamine metabolites and activities of thiamine-dependent enzymes are impaired in Alzheimer's disease (AD.To clarify the mechanism for the reduction of thiamine diphosphate (TDP, an active form of thiamine and critical coenzyme of glucose metabolism, in AD.Forty-five AD patients clinically diagnosed and 38 age- and gender-matched control subjects without dementia were voluntarily recruited. The contents of blood TDP, thiamine monophosphate (TMP, and thiamine, as well as the activities of thiamine diphosphatase (TDPase, thiamine monophosphatase (TMPase, and thiamine pyrophosphokinase (TPK, were assayed by high performance liquid chromatography.Blood TDP contents of AD patients were significantly lower than those in control subjects (79.03 ± 23.24 vs. 127.60 ± 22.65 nmol/L, P 0.05. Blood TDP levels correlated negatively with TDPase activities (r = -0.2576, P = 0.0187 and positively with TPK activities (r = 0.2426, P = 0.0271 in all participants.Enhanced TDPase and TMPase activities may contribute to the reduction of TDP level in AD patients. The results imply that an imbalance of phosphorylation-dephosphorylation related to thiamine and glucose metabolism may be a potential target for AD prevention and therapy.

  3. [Application of ″Fu Yang and activating blood circulation″ in treatment of unstable angina pectoris patients].

    Science.gov (United States)

    Gao, Jia-Liang; Li, Jun; Wang, Jie

    2016-02-01

    Coronary heart disease(CHD) has become a major public health problem in the world, while the unstable angina (UA) is one of an important type. Hypofunction of yang qi in chest and cardiac blood stasis has been considered as the basic pathogenesis of UA.According to the deficiency of yang and blood stasis run through the process of CHD, fu yang and activating blood circulation could be main treatment. Wenxin decoction which has the function of fu yang and activating blood circulation, not only can effectively improve the symptoms of angina pectoris, the ischemic ECG, but also can significantly improve blood rheology, blood lipids and so on. So deepening the theory of ″fu yang and activating blood circulation″ and the application of ″Wenxin decoction″ in the treatment of UA would have an important clinical value for improving the therapeutic efficacy of CHD. Copyright© by the Chinese Pharmaceutical Association.

  4. In vitro antifungal activity of dragon's blood from Croton urucurana against dermatophytes.

    Science.gov (United States)

    Gurgel, Luilma A; Sidrim, J J C; Martins, Domingos T; Cechinel Filho, V; Rao, Vietla S

    2005-02-28

    Based on ethnobotanical approach, the dragon's blood collected from Croton urucurana Baill. bark (Euphorbiaceae) was tested for antifungal activity against five dermatophytes by paper disk diffusion method. The minimal inhibitory concentration (MIC) showing no visible fungal growth was also determined, using tube dilution technique. The test dermatophytes were Tricophyton tonsurans, Trichophyton mentagrophytes, Trichophyton rubrum, Microsporum canis and Epidermophyton floccossum. The dragon's blood (0.175-3.0 mg/ml) exhibited an inhibition zone range of 7.6-26.9 mm against all the tested fungi with minimal inhibitory concentrations of 1.25-2.5 mg/ml.

  5. Neutrophil granule proteins generate bactericidal ammonia chloramine on reaction with hydrogen peroxide.

    Science.gov (United States)

    Green, Jessie N; Chapman, Anna L P; Bishop, Cynthia J; Winterbourn, Christine C; Kettle, Anthony J

    2017-12-01

    The neutrophil enzyme, myeloperoxidase, by converting hydrogen peroxide (H 2 O 2 ) and chloride to hypochlorous acid (HOCl), provides important defense against ingested micro-organisms. However, there is debate about how efficiently HOCl is produced within the phagosome and whether its reactions with phagosomal constituents influence the killing mechanism. The phagosome is a small space surrounding the ingested organism, into which superoxide, H 2 O 2 and high concentrations of proteins from cytoplasmic granules are released. Previous studies imply that HOCl is produced in the phagosome, but a large proportion should react with proteins before reaching the microbe. To mimic these conditions, we subjected neutrophil granule extract to sequential doses of H 2 O 2 . Myeloperoxidase in the extract converted all the H 2 O 2 to HOCl, which reacted with the granule proteins. 3-Chlorotyrosine, protein carbonyls and large amounts of chloramines were produced. At higher doses of H 2 O 2 , the extract developed potent bactericidal activity against Staphylococcus aureus. This activity was due to ammonia monochloramine, formed as a secondary product from protein chloramines and dichloramines. Isolated myeloperoxidase and elastase also became bactericidal when modified with HOCl and antibacterial activity was seen with a range of species. Comparison of levels of protein modification in the extract and in phagosomes implies that a relatively low proportion of phagosomal H 2 O 2 would be converted to HOCl, but there should be sufficient for substantial protein chloramine formation and some breakdown to ammonia monochloramine. It is possible that HOCl could kill ingested bacteria by an indirect mechanism involving protein oxidation and monochloramine formation. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Extracellular Histones Increase Tissue Factor Activity and Enhance Thrombin Generation by Human Blood Monocytes.

    Science.gov (United States)

    Gould, Travis J; Lysov, Zakhar; Swystun, Laura L; Dwivedi, Dhruva J; Zarychanski, Ryan; Fox-Robichaud, Alison E; Liaw, Patricia C

    2016-12-01

    Sepsis is characterized by systemic activation of inflammatory and coagulation pathways in response to infection. Recently, it was demonstrated that histones released into the circulation by dying/activated cells may contribute to sepsis pathology. Although the ability of extracellular histones to modulate the procoagulant activities of several cell types has been investigated, the influence of histones on the hemostatic functions of circulating monocytes is unknown. To address this, we investigated the ability of histones to modulate the procoagulant potential of THP-1 cells and peripheral blood monocytes, and examined the effects of plasmas obtained from septic patients to induce a procoagulant phenotype on monocytic cells. Tissue factor (TF) activity assays were performed on histone-treated THP-1 cells and blood monocytes. Exposure of monocytic cells to histones resulted in increases in TF activity, TF antigen, and phosphatidylserine exposure. Histones modulate the procoagulant activity via engagement of Toll-like receptors 2 and 4, and this effect was abrogated with inhibitory antibodies. Increased TF activity of histone-treated cells corresponded to enhanced thrombin generation in plasma determined by calibrated automated thrombography. Finally, TF activity was increased on monocytes exposed to plasma from septic patients, an effect that was attenuated in plasma from patients receiving unfractionated heparin (UFH). Our studies suggest that increased levels of extracellular histones found in sepsis contribute to dysregulated coagulation by increasing TF activity of monocytes. These procoagulant effects can be partially ameliorated in sepsis patients receiving UFH, thereby identifying extracellular histones as a potential therapeutic target for sepsis treatment.

  7. Concentration of Some Minerals and Activity of Alkaline Phosphate in Blood Plasma of Irradiated Chickens

    International Nuclear Information System (INIS)

    Simpraga, M.; Milinkovic-Tur, S.; Stojevic, Z.; Kraljevic, P.; Starcevic, Z.; Miljanic, S.

    1998-01-01

    The results of our previous papers have shown the changes on hematological parameters, some enzymes activity and mineral metabolism in blood plasma of chickens after internal contamination with a lethal amount of radioactive isotope 32 P. So, this time an attempt has been made to investigate the effects of whole body irradiation by semilethal dose (8 Gy) of gamma-rays on some mineral concentration and alkaline phosphatase activity in blood plasma of chickens for early detecting of acute radiation syndrome. Experiments were carried out on fifty-days-old hybrid chickens of the 'Jata' breed of male sex with 2 to 2.3 kg of body mass. The animals were divided into two groups with five chickens in each group. The experimental group was whole body irradiated by gamma-rays ( 60 Co) with single dose of 8 Gy. Blood samples for biochemical analysis were drawn from wing vein on day before irradiation and on the 1st, 3rd, 5th, 7th, 9th and 15th days after irradiation. The concentration of calcium, inorganic phosphorus and magnesium as well as the activity of alkaline phosphatase, were determined in blood plasma. The statistical analysis was performed and the results obtained are shown as a mean value. The significance of the changes was checked according to the Student and Fisher t-test. Obtained results have shown that activity of alkaline phosphatase in blood plasma of whole body gamma-rays irradiated chickens significantly changes only on the first day after irradiation. In the same time the calcium, phosphorus and magnesium concentration were not significantly changed during the whole experiment. Therefore, we can conclude that the concentration of this mineral would not be an acceptable parameter for early detecting of acute radiation syndrome in 50 day-old chickens after irradiation by semilethal dose of gamma-radiation. (author)

  8. Vibroacustic microvibrations enhance kidney blood supply, glomerular filtration and glutathione peroxidase activity in spontaneously hypertensive rats.

    Science.gov (United States)

    Miloradović, Zoran; Mihailović-Stanojević, Nevena; Jovović, Đurđica; Ivanov, Milan; Vajić, Una J; Karanović, Danijela; Grujić Milanović, Jelica

    2015-01-01

    Limited numbers of studies include research of microvibration therapy in experimental models. We examined effects of chronic vibroacustic-microvibration treatment on haemodynamics and anti-oxidative defense in experimental hypertension. Study was performed on chronically treated hypertensive and normotensive Wistar rats. Mean arterial pressure (MAP), cardiac output (CO), renal blood flow (RBF), glomerular filtration and activity of anti-oxidative enzymes were determined after three weeks treatment. Vibroacustic treatment had no influence on MAP and CO, but RBF was increased in both groups of treated rats. Additionally, vibroacustic treatment enhanced diuresis and increased glomerular filtration in hypertensive rats. Glutathione peroxidase (GSH-Px) activity was elevated in both treated rat strains, but activity of superoxide dismutase was unchanged. We conclude that microvibration treatment doesn't ameliorate hypertension but improves renal blood supply (trough diminished renal vascular resistance), glomerular filtration, diuresis, and enhances glutathione dependent anti-oxidant defense with more important beneficials in hypertensive animals.

  9. A high-fat meal does not activate blood coagulation factor VII in minipigs

    DEFF Research Database (Denmark)

    Olsen, A K; Larsen, L F; Bladbjerg, E-M

    2001-01-01

    It is a matter of debate whether postprandial activation of blood coagulation factor VII (FVII) is associated with an increased risk of thrombosis. To clarify this question, an animal model in which consequences of dietary FVII activation can be studied in a more detailed way would be an important...... tool. We studied postprandial FVII activation in seven non-fasting Göttingen minipigs. Intralipid (4 g/kg) was administered through a gastric tube in two fractions at 9.00 a.m. (one-third of total dose) and 10.30 a.m. (two-thirds of total dose). Blood samples were drawn 0.5 h before (baseline) and 2, 3....../l (baseline) to 2.56 mmol/l 5 h postprandially (P meal does not seem...

  10. Sustained strenuous exercise in sled dogs depresses three blood copper enzyme activities.

    Science.gov (United States)

    DiSilvestro, R A; Hinchcliff, K W; Blostein-Fujii, A

    2005-01-01

    Studies show mixed conclusions about acute responses of copper status to strenuous exercise. Because copper function involves metalloenzyme activities, which might take days to change, the present study examined the response of three copper metalloenzyme activities to sustained strenuous exercise in sled dogs. A race lasting 12-15 d depressed activities for both plasma ceruloplasmin and erythrocyte superoxide dismutase in dogs consuming commercial dog foods and meats. A shorter, 3-d training run for dogs fed a commercial balanced diet also depressed ceruloplasmin activities but not superoxide dismutase activities. Dogs fed the same diet but that did not run showed no changes in either parameter. Activities of a third copper enzyme, plasma diamine oxidase, also decreased after a 3-d training run. In summary, blood activities of three copper enzymes were depressed by sustained strenuous exercise in sled dogs.

  11. Low blood glucose precipitates spike-and-wave activity in genetically predisposed animals.

    Science.gov (United States)

    Reid, Christopher A; Kim, Tae Hwan; Berkovic, Samuel F; Petrou, Steven

    2011-01-01

    Absence epilepsies are common, with a major genetic contribution to etiology. Certain environmental factors can influence absence occurrence but a complete understanding of absence precipitation is lacking. Herein we investigate if lowering blood glucose increases spike-wave activity in mouse models with varying seizure susceptibility. Three mouse models were used: an absence seizure model based on the knockin of a human GABA(A) γ2(R43Q) mutation (DBA(R43Q)), the spike-wave discharge (SWD)-prone DBA/2J strain, and the seizure resistant C57Bl/6 strain. Electrocorticography (ECoG) studies were recorded to determine SWDs during hypoglycemia induced by insulin or overnight fasting. An insulin-mediated reduction in blood glucose levels to 4 mm (c.a. 40% reduction) was sufficient to double SWD occurrence in the DBA(R43Q) model and in the SWD-prone DBA/2J mouse strain. Larger reductions in blood glucose further increased SWDs in both these models. However, even with large reductions in blood glucose, no discharges were observed in the seizure-resistant C57Bl/6 mouse strain. Injection of glucose reversed the impact of insulin on SWDs in the DBA(R43Q) model, supporting a reduction in blood glucose as the modulating influence. Overnight fasting reduced blood glucose levels to 4.5 mm (c.a. 35% reduction) and, like insulin, caused a doubling in occurrence of SWDs. Low blood glucose can precipitate SWDs in genetically predisposed animal models and should be considered as a potential environmental risk factor in patients with absence epilepsy. Wiley Periodicals, Inc. © 2010 International League Against Epilepsy.

  12. Severe reduction of blood lysosomal acid lipase activity in cryptogenic cirrhosis: A nationwide multicentre cohort study.

    Science.gov (United States)

    Angelico, Francesco; Corradini, Stefano Ginanni; Pastori, Daniele; Fargion, Silvia; Fracanzani, Anna Ludovica; Angelico, Mario; Bolondi, Luigi; Tozzi, Giulia; Pujatti, Pietro Luigi; Labbadia, Giancarlo; Corazza, Gino Roberto; Averna, Maurizio; Perticone, Francesco; Croce, Giuseppe; Persico, Marcello; Bucci, Tommaso; Baratta, Francesco; Polimeni, Licia; Del Ben, Maria; Violi, Francesco

    2017-07-01

    Blood lysosomal acid lipase (LAL) is reduced in non-alcoholic steatohepatitis, which is the major cause of cryptogenic cirrhosis (CC); few data on LAL activity in CC do exist. We investigated LAL activity in a cohort of patients with liver cirrhosis. This is a multicentre cohort study including 274 patients with liver cirrhosis of different aetiology from 19 centres of Internal Medicine, Gastroenterology and Hepatology distributed throughout Italy. Blood LAL activity (nmol/spot/h) was measured with dried blood spot extracts using Lalistat 2. Overall, 133 patients had CC, and 141 patients had cirrhosis by other causes (61 viral, 53 alcoholic, 20 alcoholic + viral, 7 autoimmune). Mean age was 64.2 ± 13.4 years, and 28.5% were women. Patients with CC were older compared to other aetiology-cirrhosis, with a lower Child-Turcotte-Pugh (CTP, p=0.003) and MELD (p=0.009) score, and a higher prevalence of cardio-metabolic risk factors and previous ischemic events. In the whole cohort, median LAL activity value was 0.58 nmol/spot/h, 0.49 and 0.65 in the groups of CC and known-aetiology cirrhosis, respectively (p=0.002). The difference remained significant after adjustment for white blood cells count (p=0.001). Multivariable linear regression analysis showed that CC (vs. known aetiology, Beta = -0.144, p=0.018), platelet count (Beta = 0.398, p < 0.001) and CTP score (Beta = -0.133, p=0.022) were associated with log-LAL activity. Similar results were found using MELD as covariate. We found a marked reduction of LAL activity in patients with cryptogenic cirrhosis compared to the other known aetiologies. A prospective study will clarify the role of LAL in chronic liver diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Enhanced biomimic bactericidal surfaces by coating with positively-charged ZIF nano-dagger arrays.

    Science.gov (United States)

    Yuan, Yuan; Zhang, Yugen

    2017-10-01

    Cicada wing surfaces are covered with dense patterns of nano-pillar structure that prevent bacterial growth by rupturing adhered microbial cells. To mimic the natural nano-pillar structure, we developed a general and simple method to grow metal organic framework (MOF) nano-dagger arrays on a wide range of surfaces. These nano-daggers possess high bactericidal activity, with log reduction >7 for Escherichia coli and Staphylococcus aureus. It was hypothesized that the positively-charged ZIF-L nano-dagger surfaces enhance bacterial cell adhesion, facilitating selective and efficient bacteria killing by the rigid and sharp nano-dagger tips. This research provides a safe and clean antimicrobial surface technology which does not require external chemicals and will not cause drug resistance. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. The effects of ramadan fasting and physical activity on blood hematological-biochemical parameters.

    Science.gov (United States)

    Attarzadeh Hosseini, Seyyed Reza; Hejazi, Keyvan

    2013-07-01

    Objective(s) : Fasting during the month of Ramadan is a religious obligation and belief for healthy adult Muslims. The aim of the present study was to determine the effects of Ramadan Fasting and physical activity on 'Blood Hematological-Biochemical Parameters'. In this study, twenty-six healthy males in two experimental groups were compared in two different instances before and after the training period. The groups which were selected by convenience sampling method were divided into two non-active fasting (n=13) and active fasting (n=13) groups. For comparison purposes between groups, paired and independent sample t-test was performed, respectively, after ensuring their normality within a significance level of P≤0.05. HDL-C increased significantly in both active and non-active fasting groups, Moreover, amount of hematocrit (Hct), red blood cell count (RBC), TC, LDL, VLDL, LDL/HDL and TC/ HDL decreased significantly. Amount of hemoglobin (Hgb) and glucose reduced significantly in the active-fasting group. The variation of the means between the groups in the Hgb index and LDL/HDL were statistically significant. Fasting during the month of Ramadan by regular physical activity caused positive alterations in Hematological-Biochemical Index. These changes may be due to the alterations in diet, biology response of the body to the starving and physical activity during this month.

  15. Microwave, sonochemical and combustion synthesized CuO nanostructures and their electrical and bactericidal properties

    Energy Technology Data Exchange (ETDEWEB)

    Karunakaran, C., E-mail: karunakaranc@rediffmail.com; Manikandan, G.; Gomathisankar, P.

    2013-12-15

    Highlights: •CuO nanoleaves synthesized by CTAB-assisted hydrothermal method. •CuO nanodiscs synthesized by CTAB-assisted sonochemical method. •Combustion synthesized CuO is highly porous. •Synthetic method and morphology influence CuO bactericidal activity. -- Abstract: Cetyltrimethylammonium bromide (CTAB)-assisted microwave synthesis of CuO provides nanoleaves and in the absence of CTAB the shape of CuO is irregular. Sonochemical synthesis of CuO using CTAB gives nanodiscs whereas irregularly shaped flake-like structure is obtained without CTAB. Combustion synthesized CuO is highly porous with innumerable large holes. CTAB does not provide any structure in combustion synthesis. Transmission electron micrographs (TEM) display the constituent nanoparticles of microwave and sonochemically synthesized CuO. The powder X-ray diffractogram (XRD) shows the sample obtained by sonochemical method in the absence of CTAB as a mixture of monoclinic CuO, cubic Cu{sub 2}O, and orthorhombic Cu(OH){sub 2}. But the rest of the samples are pure CuO in monoclinic phase. The selected area electron diffractograms (SAED) of the microwave and sonochemically synthesized samples, in the presence as well as in the absence of CTAB, confirm the monoclinic phase of CuO and indicates the presence of amorphous CuO in traces. All the samples are characteristic of Fourier Transform infrared (FT-IR) Cu–O stretching frequencies. The method of synthesis and also the morphology influence the electrical properties as well as the bactericidal activity of CuO.

  16. Effects of Resistance Training on Matrix Metalloproteinase Activity in Skeletal Muscles and Blood Circulation During Aging

    Directory of Open Access Journals (Sweden)

    Ivo V. de Sousa Neto

    2018-03-01

    Full Text Available Aging is a complex, multifactorial process characterized by the accumulation of deleterious effects, including biochemical adaptations of the extracellular matrix (ECM. The purpose of this study was to investigate the effects of 12 weeks of resistance training (RT on metalloproteinase 2 (MMP-2 activity in skeletal muscles and, MMP-2 and MMP-9 activity in the blood circulation of young and old rats. Twenty-eight Wistar rats were randomly divided into four groups (n = 7 per group: young sedentary (YS; young trained (YT, old sedentary (OS, and old trained (OT. The stair climbing RT consisted of one training session every 2 other day, with 8–12 dynamic movements per climb. The animals were euthanized 48 h after the end of the experimental period. MMP-2 and MMP-9 activity was measured by zymography. There was higher active MMP-2 activity in the lateral gastrocnemius and flexor digitorum profundus muscles in the OT group when compared to the OS, YS, and YT groups (p ≤ 0.001. Moreover, there was higher active MMP-2 activity in the medial gastrocnemius muscle in the OT group when compared to the YS and YT groups (p ≤ 0.001. The YS group presented lower active MMP-2 activity in the soleus muscle than the YT, OS, OT groups (p ≤ 0.001. With respect to active MMP-2/9 activity in the bloodstream, the OT group displayed significantly reduced activity (p ≤ 0.001 when compared to YS and YT groups. In conclusion, RT up-regulates MMP-2 activity in aging muscles, while down-regulating MMP-2 and MMP-9 in the blood circulation, suggesting that it may be a useful tool for the maintenance of ECM remodeling.

  17. Effect of Active and Passive Recovery on Athletes' White Blood Cell Count

    Directory of Open Access Journals (Sweden)

    P. Piraki, MA

    2008-07-01

    Full Text Available Background and ObjectivesExercise affects the immune system. The aim of this study is comparison of the effect of active and passive recovery (AR and RR, respectively on differential white blood cell (WBC count after an exhaustive exercise session in athlete males.Methods Twenty male athletes who signed an informed consent form were randomly divided in to two equal groups. Their blood samples were drawn at rest, immediately after an exhaustive exercise session, immediately after 15 minutes active and passive recovery from an exhaustive exercise session. A WBC’s (lymphocytes, monocytes, neutrophils, basohils, and eosinophils count was done on all of these samples.This exercise protocol was based on the Bruce Protocol Treadmill Stress Test until feeling excessive fatigue followed by AR (first group, and RR (second group.Wilcoxon signed-rank and Mann-Whitney test were used for descriptive and statistical analysis on collected raw data. Statistical significance in this analysis was set at P ≤ 0.05.ResultsA session of exhaustive exercise increased the number of WBCs (except for eosinophils with a statistical significant differences of (P0.05.ConclusionThe results show a session of exhaustive exercise increases the blood leukocytes, except for eosinophils. Also, taking 15 minutes recovery (AR or RR has no effect on athlete's WBC count. It means the type of recovery has no special and different effect on athlete's WBC count. In fact, if there are any changes in WBC count during or after exhaustive exercise, they are not due to the type of 15 minutes recovery. Furthermore, under the conditions of this study after completing the AR and RR, number of the blood leukocytes was over their basal level.Keywords: Active Recovery, Passive Recovery, White Blood Cell Count, Athletes.

  18. Microparticles from stored red blood cells enhance procoagulant and proinflammatory activity.

    Science.gov (United States)

    Fischer, Dania; Büssow, Julian; Meybohm, Patrick; Weber, Christian Friedrich; Zacharowski, Kai; Urbschat, Anja; Müller, Markus Matthias; Jennewein, Carla

    2017-11-01

    The pathomechanisms of morbidity due to blood transfusions are not yet entirely understood. Elevated levels of red blood cell-derived microparticles (RMPs) are found in coagulation-related pathologies and also in stored blood. Previous research has shown that RMPs mediate transfusion-related complications by the intrinsic pathway. We hypothesized that RMPs might play a role in post-transfusion thrombotic complications by enhancing procoagulant activity also through the extrinsic pathway of coagulation. In this laboratory study, blood from 18 healthy volunteers was stimulated with microparticles from expired stored red blood cells. Various clotting parameters were recorded. Flow cytometry, enzyme-linked immunosorbent assays, and real-time polymerase chain reaction were used to investigate possible mediating mechanisms. The addition of RMPs shortened the clotting time from 194 to 161 seconds (p monocytes and in plasma. TF messenger RNA expression increased in a time-dependent and concentration-dependent manner. There was a significant induction of interleukin-1β and interleukin-6. After stimulation with RMPs, there was a significant increase in the number of activated platelets, an increased percentage of PAC-1/CD62P (procaspase activating compound-1/platelet surface P-selectin) double-positive platelets, and an increased number of platelet-neutrophil duplets and platelet-monocyte duplets, indicating enhanced interaction of platelets with neutrophils and monocytes. Levels of CXCL-8 (C-X-C motif chemokine ligand 1) and interleukin-6 were significantly higher after treatment with RMPs. Our results suggest that RMPs trigger coagulation through TF signaling, induce the secretion of proinflammatory cytokines, and induce cell-cell interaction between platelets and neutrophils. Thus, under certain conditions, RMPs could play a role in post-transfusion complications through these mechanisms. © 2017 AABB.

  19. Blood flow to long bones indicates activity metabolism in mammals, reptiles and dinosaurs.

    Science.gov (United States)

    Seymour, Roger S; Smith, Sarah L; White, Craig R; Henderson, Donald M; Schwarz-Wings, Daniela

    2012-02-07

    The cross-sectional area of a nutrient foramen of a long bone is related to blood flow requirements of the internal bone cells that are essential for dynamic bone remodelling. Foramen area increases with body size in parallel among living mammals and non-varanid reptiles, but is significantly larger in mammals. An index of blood flow rate through the foramina is about 10 times higher in mammals than in reptiles, and even higher if differences in blood pressure are considered. The scaling of foramen size correlates well with maximum whole-body metabolic rate during exercise in mammals and reptiles, but less well with resting metabolic rate. This relates to the role of blood flow associated with bone remodelling during and following activity. Mammals and varanid lizards have much higher aerobic metabolic rates and exercise-induced bone remodelling than non-varanid reptiles. Foramen areas of 10 species of dinosaur from five taxonomic groups are generally larger than from mammals, indicating a routinely highly active and aerobic lifestyle. The simple measurement holds possibilities offers the possibility of assessing other groups of extinct and living vertebrates in relation to body size, behaviour and habitat.

  20. [Physical activity level and home blood pressure measurement: Pilot study "Acti-HTA"].

    Science.gov (United States)

    Sosner, P; Ott, J; Steichen, O; Bally, S; Krummel, T; Brucker, M; Lequeux, B; Dourmap, C; Llaty, P; Le Coz, S; Baguet, S; Miranne, A; Labrunée, M; Gremeaux, V; Lopez-Sublet, M

    2015-06-01

    While physical activity (PA) is recommended for high blood pressure management, the level of PA practice of hypertensive patients remains unclear. We aimed to assess the association between the level of both PA and blood pressure of individuals consulting in 9 hypertension specialist centres. Eighty-five hypertensive patients were included (59 ± 14 years, 61% men, 12% smokers, 29% with diabetes). Following their consultation, they performed home blood pressure measurement (HBPM) over 7 days (2 in the morning+2 in the evening), they wrote in a dedicated form their daily activities to estimate the additional caloric expenditure using Acti-MET device (built from International physical Activity Questionnaire [IPAQ]). Thus, patients completed a self-administered questionnaire "score of Dijon" (distinguishing active subjects with a score>20/30, from sedentaryactive" subjects (48.9% vs. 34.2%, P=0.1773). In conclusion, our results demonstrate a "tendency" to a higher level of reported PA for subjects whose hypertension was controlled. This encourages us to continue with a study that would include more subjects, which would assess PA level using an objective method such as wearing an accelerometer sensor. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  1. Glutathione peroxidase (GPX activity in blood of ewes on farms in different scrapie categories in Iceland

    Directory of Open Access Journals (Sweden)

    Eiríksson Tryggvi

    2008-06-01

    Full Text Available Abstract Background Preliminary studies indicated decreased glutathione peroxidase (GPX activity in blood of ewes on scrapie-afflicted farms. Other studies have shown decreased GPX activity in brain of prion-infected mice and in prion-infected cells in vitro. The aim of this study was to examine the GPX activity in blood as well as the distribution of GPX-activity levels from ewes on farms in scrapie-afflicted areas in Iceland. Methods Blood samples were collected from 635 ewes (non-pregnant [n = 297] and pregnant [n = 338] on 40 farms in scrapie-afflicted areas during the years 2001–2005, for analysis of GPX activity. The farms were divided into three categories: 1. Scrapie-free farms (n = 14; 2. Scrapie-prone farms (earlier scrapie-afflicted, restocked farms (n = 12; 3. Scrapie-afflicted farms (n = 14. For comparison, 121 blood samples were also collected from non-pregnant ewes on one farm (farm A in a scrapie-free area (scrapie never registered. Chi-square test was used to test for normal distribution of GPX-results, and Kruskal-Wallis test to compare GPX-results between categories. Results The GPX-results appeared to be biphasically distributed in ewes in all three scrapie categories and on farm A. The presumptive breaking point was about 300 units g Hb-1. About 30–50% of the GPX-results from ewes in all three scrapie categories were below 300 units g Hb-1 but only about 13% of the GPX-results from ewes on farm A. The mean GPX activity was highest on farm A, and was significantly lower on scrapie-prone farms than on scrapie-free or scrapie-afflicted farms (non-pregnant and pregnant ewes: P Conclusions 1 the distribution of GPX-results in blood of Icelandic ewes apparently has a biphasic character; 2 the GPX-results were higher in ewes on one farm in a scrapie-free area than in ewes on farms in the scrapie-afflicted areas; 3 GPX-activity levels were significantly lowest on earlier scrapie-afflicted, restocked farms, which might have a

  2. Blood pressure, cardiorespiratory fitness and body mass: Results from the Tromsø Activity Study

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    Aina Emaus

    2011-08-01

    Full Text Available Aims: Modifiable lifestyle factors, as cardiorespiratory fitness (CRF and body mass, may prevent hypertension.However, it remains unclear whether blood pressure is associated with CRF, independently of body mass index (BMI. Thus, the purpose was to study the relationship between CRF, body composition and blood pressure among 40-44 year old men and women.Methods: During 2007-2008, 12,900 men and women aged 30-85 years attended the sixth survey of the Tromsø study. Blood pressure (mm Hg, height (cm and weight (kg were measured and body mass index (BMI kg/m2 was estimated. In a sub-study, the Tromsø Activity Study, CRF [VO2max (ml/kg/min] was objectively measured using a treadmill test among 313 healthy men and women aged 40-44 years.Results: Among men and women participating in both studies, the mean BMI was 27.1 kg/m2 for men and 25.1 kg/m2 for women. Mean arterial blood pressure (MAP was 92.4 mm Hg for men and 86.0 mm Hg for women. The proportion defined as pre-hypertensive/hypertensive (systolic/diastolic blood pressure > 120/80 were 33% and 56% for women and men, respectively. The proportion of low, medium and high CRF for both sexes combined differed significantly (p < 0.0001 by BMI level (< 25 or ≥ 25 kg/m2. Increased fitness tended to reduce blood pressure among overweight and obese men (p trend = 0.03, whereas increased fitness tended to reduce blood pressure among normal weighted women (p trend = 0.01.Conclusion: Among healthy 40-44 year old men and women in this study, BMI was positively associated and CRF was negatively associated with blood pressure. Moreover, our results suggest that BMI may be a more important factor than CRF in predicting systolic blood pressure in both sexes. However, cardiorespiratoryfitness and weight control may both be important targets for prevention of hypertension

  3. Physical activity in People with High Blood Pressure: A Case – control Study

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    M Momayyezi

    2016-03-01

    Full Text Available Introduction: Regular physical activity is one of the main factors in maintaining and improving health throughout life. International studies have shown that regular exercise can increase life expectancy and reduce morbidity and mortality from chronic diseases. This study was conducted to determine the amount of physical activity in people with high blood pressure and comparing them with healthy people. Methods: The present study was a case-control study on 160 people (80 patients with hypertension (case group and 80 healthy individuals (control group. People with normal blood pressure were in the case group and the control group (systolic 140 mmHg or above and diastolic 90 mmHg or above were in the case group. Data were collected using a questionnaire with the simple random sampling. The first part of questionnaire included background characteristics and socio-economic status; the second part of the questionnaire measured physical activity level using international physical activity questionnaire (IPAQ. The statistical analyses included descriptive statistics, the Mann–Whitney test, Chi-square test, and logistic regression analysis using SPSS/16. Assessment of physical activity in case and control groups showed that 13.8% of cases and 27.5% of controls had physical activity in the last week; this difference was statistically significant. Based on the results, the risk of hypertension in people without physical activity was 37.2 times more than the people who had physical activity in the last week. The results of logistic regression showed that physical activity, education level and income were effective factors on hypertension. The results showed that physical activity with moderate and severe levels have a protective effect against hypertension. Also, people with less income and less education had a greater chance of hypertension than others. The results indicated physical activity reduces the risk of hypertension. These findings emphasize

  4. Associations among Environmental Supports, Physical Activity, and Blood Pressure in African American Adults in the PATH Trial

    OpenAIRE

    Coulon, Sandra M.; Wilson, Dawn K.; Egan, Brent M.

    2013-01-01

    High blood pressure disproportionately affects African American adults and is a leading cause of stroke and heart attack. Engaging in recommended levels of physical activity reduces blood pressure, and social and physical environmental supports for physical activity may increase engagement in physical activity. Based on social cognitive theory within a bioecological framework, the present study tested hypotheses that perceived peer social support for physical activity and neighborhood walkabi...

  5. Bactericidal Antibiotics Increase Hydroxyphenyl Fluorescein Signal by Altering Cell Morphology

    DEFF Research Database (Denmark)

    Paulander, Wilhelm; Wang, Ying; Folkesson, Sven Anders

    2014-01-01

    It was recently proposed that for bactericidal antibiotics a common killing mechanism contributes to lethality involving indirect stimulation of hydroxyl radical (OH center dot) formation. Flow cytometric detection of OH center dot by hydroxyphenyl fluorescein (HPF) probe oxidation was used...... to support this hypothesis. Here we show that increased HPF signals in antibiotics-exposed bacterial cells are explained by fluorescence associated with increased cell size, and do not reflect reactive oxygen species (ROS) concentration. Independently of antibiotics, increased fluorescence was seen...... for elongated cells expressing the oxidative insensitive green fluorescent protein (GFP). Although our data question the role of ROS in lethality of antibiotics other research approaches point to important interplays between basic bacterial metabolism and antibiotic susceptibility. To underpin...

  6. Bactericidal properties of silver films on intramedullary implants

    Science.gov (United States)

    Gallagher, C.; Walker, C.; Cortes, E.; Hettinger, Jeffrey; Krchnavek, R.; Caputo, G. A.; Ostrum, R.

    2011-03-01

    We report on investigations of silver films on titanium and stainless steel substrates as anti-bacterial coatings for intramedullary nails used in orthopedic trauma. Silver films are deposited using a magnetron sputtering technique from a single elemental target. The deposition parameter (energy, pressure, and temperature) dependence of the silver film microstructure and adhesion will be presented. Preliminary measurements of the effectiveness of the silver films as a bactericide on S. aureus bacteria demonstrate that the films are effective destroying the bacteria. The process of this investigation will be presented. Preliminary transmission electron microscopy measurements will also presented which image healthy and damaged bacteria helping to identify the fundamental mechanism leading to the effectiveness of silver as an anti-bacterial coating. We acknowledge the support of Rowan University, College of Liberal Arts and Sciences.

  7. Bactericidal antibiotics increase hydroxyphenyl fluorescein signal by altering cell morphology.

    Directory of Open Access Journals (Sweden)

    Wilhelm Paulander

    Full Text Available It was recently proposed that for bactericidal antibiotics a common killing mechanism contributes to lethality involving indirect stimulation of hydroxyl radical (OH• formation. Flow cytometric detection of OH• by hydroxyphenyl fluorescein (HPF probe oxidation was used to support this hypothesis. Here we show that increased HPF signals in antibiotics-exposed bacterial cells are explained by fluorescence associated with increased cell size, and do not reflect reactive oxygen species (ROS concentration. Independently of antibiotics, increased fluorescence was seen for elongated cells expressing the oxidative insensitive green fluorescent protein (GFP. Although our data question the role of ROS in lethality of antibiotics other research approaches point to important interplays between basic bacterial metabolism and antibiotic susceptibility. To underpin such relationships, methods for detecting bacterial metabolites at a cellular level are needed.

  8. Bactericidal Antibiotics Increase Hydroxyphenyl Fluorescein Signal by Altering Cell Morphology

    Science.gov (United States)

    Folkesson, Anders; Charbon, Godefroid; Løbner-Olesen, Anders; Ingmer, Hanne

    2014-01-01

    It was recently proposed that for bactericidal antibiotics a common killing mechanism contributes to lethality involving indirect stimulation of hydroxyl radical (OH•) formation. Flow cytometric detection of OH• by hydroxyphenyl fluorescein (HPF) probe oxidation was used to support this hypothesis. Here we show that increased HPF signals in antibiotics-exposed bacterial cells are explained by fluorescence associated with increased cell size, and do not reflect reactive oxygen species (ROS) concentration. Independently of antibiotics, increased fluorescence was seen for elongated cells expressing the oxidative insensitive green fluorescent protein (GFP). Although our data question the role of ROS in lethality of antibiotics other research approaches point to important interplays between basic bacterial metabolism and antibiotic susceptibility. To underpin such relationships, methods for detecting bacterial metabolites at a cellular level are needed. PMID:24647480

  9. Basal blood parameters of horses subjected to aerobic activity fed with lipidic concentrated

    Directory of Open Access Journals (Sweden)

    Kátia de Oliveira

    2012-02-01

    Full Text Available The feeding diets were evaluated containing low and high levels of soybean oil for horses athletes subjected to two protocols of aerobic training on the response of basal blood biochemical parameters. Four horses were used in latin square design with treatments in a 2 x 2 factorial arrangement. Treatments consisted levels of 5 and 15% oil concentrates and two aerobic training, 40' and 60' minutes. Plasmatic parameters were monitored, triglyceride (TG, total cholesterol (TC, glucose (GLU and lactate (LAC, during basal metabolism. The TG, TC, GLU and LAC from horses at rest were not affected (P> 0.05 neither of diet and physical activity, 0.21, 3.79, 4.18, 0.93 mmol L-1, respectively. It can be concluded that offer concentrate with high content of soybean oil to athletic horses in aerobic activities can be performed without altering the blood biochemical profile of basal metabolism.

  10. Influence of circulating antigen on blood pool activity of a radioiodinated monoclonal antibody

    International Nuclear Information System (INIS)

    Zalutsky, M.R.; Knapp, R.C.; Bast, R.C. Jr.

    1988-01-01

    Athymic mice with and without circulating CA 125 antigen were injected with 0.1-100 μg of 131 I-labeled OC 125 F(ab') 2 antibody fragment. Both the blood clearance of 131 I activity and the change in serum CA 125 were monitored over 24 h. Influence of CA 125 on blood pool activity could be avoided only at the 100 μg dose. In patient studies, circulating CA 125 levels decreased for the first 2 h after injection of OC 125 F(ab') 2 but generally returned to preinjection levels shortly thereafter. In vitro binding studies using the sera from patients injected with 131 I-labeled OC 125 F(ab') 2 suggest that circulating CA 125 could interfere with the tumor uptake of the labeled antibody. (author)

  11. Phagocytic activity of peripheral blood and crevicular phagocytes in health and periodontal disease

    Directory of Open Access Journals (Sweden)

    Asif K

    2010-01-01

    Full Text Available Background: Neutrophils constitute the main phagocytic cell system in mammalian host defense against an infecting agent. Abnormalities in leukocyte number and function are associated with increased susceptibility to periodontal diseases. The purpose of this study is to evaluate the in vitro phagocytic properties of crevicular and peripheral blood neutrophils in healthy and periodontitis subjects. Patients and Methods: A total of 30 subjects, that is, 10 patients in each of the following three groups: healthy controls, chronic periodontitis (CP, and localized aggressive periodontitis (LAP, were included in the study. The neutrophils were isolated from the peripheral blood and gingival crevice and tested for phagocytosis of Candida albicans. The percentage of leukocytes with ingested C. albicans was determined by light microscopy. Results: A significant reduction in the phagocytic activity of crevicular fluid polymorphonuclear neutrophils (CF-PMN of LAP subjects (mean: 54.3±7(P< 0.001 was observed, compared to healthy controls (mean: 74.2±9 and chronic periodontitis subjects (mean: 69±9(P=0.352. The mean percentage of peripheral blood polymorphonuclear neutrophils (PMNs with phagocytosis of opsonized C. albicans in LAP patients was significantly reduced (mean: 74.9±5(P< 0.0068 compared to the phagocytic activity of neutrophils from controls (mean:82.1±3 and chronic periodontitis subjects (mean: 82.0±5(P=0.970. There was no significant reduction in the phagocytic activity of CF PMNs (mean: 69±9 (P=0.35 and peripheral blood PMNs (mean: 82.5(P=0.97 in the chronic periodontitis group when compared to the control group. Conclusion: The phagocytic activity of both crevicular and peripheral neutrophils in subjects with periodontitis is altered, increasing the susceptibility to periodontitis. Thus individual susceptibility may be an additional and important modifying factor in the pathogenesis of periodontal disease.

  12. Bactericidal and cytotoxic effects of Erythrina fusca leaves aquadest extract

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    Janti Sudiono

    2013-03-01

    Full Text Available Background: Empirically, Erythrina fusca has been used as traditional herb for its antibacterial and antiinflammation properties. Periodontal disease is one of the most oral infectious diseases with microorganism predominated as the contributing factors. Porphyromonas gingivalis (P. gingivalis is one of the main bacteria pathogen found in periodontal diseases. Purpose: The purpose of this study was to examine the bactericidal effect of Erythrina fusca Leaves Aquadest Extract (EFLAE at various concentrations on P. gingivalis and cytotoxic effect on fibroblast. Methods: Pure P. gingivalis was cultured in Brain Heart Infusion (BHI medium for 24 hours with or without various concentrations of treatment of EFLAE. Calculation and statistical analysis of remaining bacteria were performed by inhibitory zone method to evaluate the EFLAE bactericidal effect and compared to chlorhexidine as positive control. To evaluate the cytotoxic effect, NIH 3T3 cells were cultured in Dulbecco’s Modification of Eagle’s Medium (DMEM containing of 10% fetal bovine serum (FBS and 1% penicillin-streptomycin, pH 7.2, in 5% CO2, and stored in humidified incubator under temperature 370 C. Cells were treated with/without various concentrations of EFLAE for 48 hours. The viable cells were then counted using 3-(4,5- Dimethylthiazol-2-yl-2,5 diphenyl tetrazodium bromide (MTT method. Results: EFLAE have bactericidal effect on P. gingivalis in a concentration dependent manner starting from 78%. The concentration of 90% EFLAE had stronger bactericidal effect (35.004 ± 1.546 than those of chlorhexidine as positive control (32.313 ± 1.619. One-way ANOVA showed significant bactericidal effect differences among concentrations of EFLAE and chlorhexidine (p<0.05 while Tuckey HSD test showed significant difference only between lower concentration of EFLAE (78%, 79% and chlorhexidine. With the highest concentration of EFLAE (100% applied in the bactericidal test, no cytotoxic effect

  13. Engineering blood meal-activated systemic immunity in the yellow fever mosquito, Aedes aegypti

    Science.gov (United States)

    Kokoza, Vladimir; Ahmed, Abduelaziz; Cho, Wen-Long; Jasinskiene, Nijole; James, Anthony A.; Raikhel, Alexander

    2000-01-01

    Progress in molecular genetics makes possible the development of alternative disease control strategies that target the competence of mosquitoes to transmit pathogens. We tested the regulatory region of the vitellogenin (Vg) gene of Aedes aegypti for its ability to express potential antipathogen factors in transgenic mosquitoes. Hermes-mediated transformation was used to integrate a 2.1-kb Vg-promoter fragment driving the expression of the Defensin A (DefA) coding region, one of the major insect immune factors. PCR amplification of genomic DNA and Southern blot analyses, carried out through the ninth generation, showed that the Vg-DefA transgene insertion was stable. The Vg-DefA transgene was strongly activated in the fat body by a blood meal. The mRNA levels reached a maximum at 24-h postblood meal, corresponding to the peak expression time of the endogenous Vg gene. High levels of transgenic defensin were accumulated in the hemolymph of bloodfed female mosquitoes, persisting for 20–22 days after a single blood feeding. Purified transgenic defensin showed antibacterial activity comparable to that of defensin isolated from bacterially challenged control mosquitoes. Thus, we have been able to engineer the genetically stable transgenic mosquito with an element of systemic immunity, which is activated through the blood meal-triggered cascade rather than by infection. This work represents a significant step toward the development of molecular genetic approaches to the control of vector competence in pathogen transmission. PMID:10908672

  14. A link between blood coagulation and prophenol oxidase activation in arthropod host defense.

    Science.gov (United States)

    Nagai, T; Kawabata, S

    2000-09-22

    Phenol oxidase, a copper-containing enzyme, is widely distributed not only in animals but also in plants and fungi, which is responsible for initiating the biosynthesis of melanin. Activation of prophenol oxidase in arthropods is important in host defense. However, the prophenol oxidase-activating system remains poorly understood at the molecular level. Here we show that the coagulation cascade of the horseshoe crab Tachypleus tridentatus is linked to prophenol oxidase activation, with the oxygen carrier hemocyanin functioning as a substitute for prophenol oxidase. Tachypleus clotting enzyme functionally transforms hemocyanin to phenol oxidase, and the conversion reaches a plateau at 1:1 stoichiometry without proteolytic cleavage. The active site-masked clotting enzyme also has the same effect, suggesting that complex formation of the clotting enzyme with hemocyanin is critical for the conversion. The two systems of blood coagulation and prophenol oxidase activation may have evolved from a common ancestral protease cascade.

  15. Size tuning of Ag-decorated TiO₂ nanotube arrays for improved bactericidal capacity of orthopedic implants.

    Science.gov (United States)

    Esfandiari, N; Simchi, A; Bagheri, R

    2014-08-01

    Surface modification of orthopedic implants using titanium dioxide nanotubes and silver nanoparticles (SNs) is a promising approach to prevent bacteria adhesion, biofilm formation, and implant infection. Herein, we utilized a straightforward and all-solution process to prepare silver-decorated TiO2 nanotube arrays with surface density of 10(3) to 10(4) per µm(2). With controlling the synthesis conditions, hexagonal closed-packed nanotubes with opening diameter of 30-100 nm that are decorated with SNs with varying sizes (12-40 nm) were prepared. Various analytical techniques were utilized to characterize the size, morphology, distribution, valance state, surface roughness, and composition of the prepared antibacterial films. The bactericidal capacity of the films were studied on Escherichia coli (E. coli) by drop-test method and correlated with the size and percentage of Ag as well as the surface density of TiO2 nanotube arrays. Synergetic effect of TiO2 nanotubes and SNs on the antibacterial activity of the composite films is shown. The bactericidal capacity is found to depend on the size characteristics of the Ag-TiO2 coating. The highest antibacterial activity is obtained for TiO2 nanotubes with opening diameter of about 100 nm and SNs with an average size of 20 nm. MTT assay using osteoblast MG63 cells was performed to examine the cell viability. We suggest that release rate of the silver ions is an important factor controlling the antibacterial activity. Additionally, the size dependency of the bactericidal capacity implies that electrical coupling between silver and TiO2 nanotubes and improved hydrophobicity of the coating might influence the bacterial behavior of the hybrid nanostructures. © 2013 Wiley Periodicals, Inc.

  16. Determination of Se and Zn elements in blood serum samples by neutron activation analysis

    International Nuclear Information System (INIS)

    Indah Kusmartini; Rukruk Rukayah; Woro Yatu NS; Muhayatun; Rochestry Sofyan

    2010-01-01

    Se and Zn are essential elements being required for activity several enzyme systems in human metabolism. The elements in blood serum as well as to obtain information regarding the health status of individuals, so that important to investigated. Commonly Se and Zn elements in blood serum are low in concentration with limited samples weight, therefore high sensitive and accurate analysis method like NAA are needed. This study aims to determine the content of the elements Se and Zn in blood serum of employee using NAA technique. The samples were freeze dried then irradiated at rabbit system facility of G.A. Siwabessy Serpong reactor with neutron flux ~10 13 n.cm -2 .s -1 for 2 hours. Then samples were counted for 50000 s by HPGe spectrometer gamma and analyzed by software GENIE 2000. Method validation was also applied by analyzing the Reference Material IAEA Animal Blood RM A-13. The range concentration of elements Se and Zn were 0.06-0.17 μg/mL and 0.56-1.37 μg/mL with overall mean 0.10 ± 0.01 μg/mL and 0.97 ± 0.07 μg/mL. The value showed that appropriate with last researcher and another country. (author)

  17. Anti-biofilm and bactericidal effects of magnolia bark-derived magnolol and honokiol on Streptococcus mutans.

    Science.gov (United States)

    Sakaue, Yuuki; Domon, Hisanori; Oda, Masataka; Takenaka, Shoji; Kubo, Miwa; Fukuyama, Yoshiyasu; Okiji, Takashi; Terao, Yutaka

    2016-01-01

    Dental caries affects people of all ages and is a worldwide health concern. Streptococcus mutans is a major cariogenic bacterium because of its ability to form biofilm and induce an acidic environment. In this study, the antibacterial activities of magnolol and honokiol, the main constituents of the bark of magnolia plants, toward planktonic cell and biofilm of S. mutans were examined and compared with those of chlorhexidine. The minimal inhibitory concentrations of magnolol, honokiol and chlorhexidine for S. mutans were 10, 10 and 0.25 µg/mL, respectively. In addition, each agent showed bactericidal activity against S. mutans planktonic cells and inhibited biofilm formation in a dose- and time-dependent manner. Magnolol (50 µg/mL) had greater bactericidal activity against S. mutans biofilm than honokiol (50 µg/mL) and chlorhexidine (500 µg/mL) at 5 min after exposure, while all showed scant activity against biofilm at 30 s. Furthermore; chlorhexidine (0.5-500 µg/mL) exhibited high cellular toxicity for the gingival epithelial cell line Ca9-22 at 1 hr, whereas magnolol (50 µg/mL) and honokiol (50 µg/mL) did not. Thus; it was found that magnolol has antimicrobial activities against planktonic and biofilm cells of S. mutans. Magnolol may be a candidate for prevention and management of dental caries. © 2015 The Societies and John Wiley & Sons Australia, Ltd.

  18. Blood troponin levels in acute cardiac events depends on space weather activity components (a correlative study).

    Science.gov (United States)

    Stoupel, Eliiyahu; Radishauskas, Richardas; Bernotiene, Gailute; Tamoshiunas, Abdonas; Virvichiute, Daiva

    2018-02-05

    Many biological processes are influenced by space weather activity components such as solar activity (SA), geomagnetic activity (GMA) and cosmic ray activity (CRA). Examples are total mortality, acute myocardial infarction (AMI), stroke (cerebrovascular accident), sudden cardiac death, some congenital maladies (congenital heart disease and Down syndrome), many events in neonatology, ophtalmology, blood pressure regulation, blood coagulation, inflammation, etc. The aim of this study was to check if the level of blood troponins (Tns) - markers of myocardial damage and recognized components of modern description of AMI - is connected with the mentioned space weather parameters. Patients admitted to a 3000-bed tertiary university hospital in Kaunas, Lithuania, with suspected AMI were the object of the study. Data for the time between 2008 and 2013 - 72 consecutive months - were studied. Of the patients, 1896 (1398 male, 498 female) had elevated troponin I (Tn I) or troponin T (Tn T, sensitive Tn) levels. Normal values were 0.00-0.03 ng/mL for Tn I and 0.00-14.00 ng/mL for Tn T. Monthly means and standard deviation of Tn I and Tn T were compared with monthly markers of SA, GMA and CRA. Pearson correlation coefficients and their probabilities were established (in addition to the consecutive graphs of both comparing physical and biological data). The cosmophysical data came from space service institutions in the United States, Russia and Finland. AMI was diagnosed in 1188 patients (62.66%), and intermediate coronary syndrome in 698 patients (36.81%). There were significant links of the Tn blood levels with four SA indices and CRA (neutron activity in imp/min); there was no significant correlation with GMA indices Ap and Cp (p=0.27 and p=0.235). Tn T levels significantly correlated with the GMA indices and not with the SA and CRA levels (Ap: r=0.77, p=0.0021; Cp: r=0.729, p=0.0047). First, the monthly level of blood Tn I in ACS is significantly correlated with the indices

  19. Evaluation of anti-inflammatory activity, effect on blood pressure & gastric tolerability of antidepressants

    Directory of Open Access Journals (Sweden)

    Preeta Kaur Chugh

    2013-01-01

    Full Text Available Background & objectives: Antidepressants are being used as analgesics for various pain related disorders like neuropathic and non neuropathic pain. Although their analgesic activity is well recognized but anti-inflammatory potential of antidepressants is still inconclusive. Since the antidepressants are used for longer duration, it becomes important to elucidate effect of anti-depressants on blood pressure and gastric mucosa. This study was undertaken to evaluate the anti-inflammatory potential of various antidepressant drugs as well as their effect on blood pressure and gastric tolerability on chronic administration in rats. Methods: Rat paw oedema model was used for studying anti-inflammatory activity, single dose of test drug (venlafaxine 20 and 40 mg/kg, amitryptline 25 mg/kg, fluoxetine 20 mg/kg was administered intraperitoneally 45 min prior to administration of 0.1 ml of 1 per cent carrageenan in sub-planter region. Oedema induced in test group was compared with normal saline treated control group. For studying effect on blood pressure and gastric tolerability, test drugs were administered for 14 days. Blood pressure was recorded on days 0, 7 and 14 using tail cuff method. On day 14, 4 h after drug administration, rats were sacrificed and stomach mucosa was examined for ulcerations. Results: Pretreatment of rats with venlafaxine (40 mg/kg resulted in a significant decrease in paw oedema as compared to control (2.4 ± 0.15 to 1.1 ± 0.16 ml, P<0.01. Similarly, in the group pretreated with fluoxetine, significant decrease in paw oedema was observed in comparison to control (P<0.05. Significant change in mean blood pressure was seen in rats pretreated with venlafaxine 40 mg/kg (126.7 ± 4.2 to 155.2 ± 9.7, P<0.05 and fluoxetine (143.5 ± 2.6 to 158.3 ± 1.2, P<0.05 on day 7. No significant difference with regard to gastric tolerability was observed among groups. Interpretation & conclusions: Our findings showed significant anti

  20. Synthetic activity of rat blood lymphocytes under acute and continuous gamma-irradiation - fluorescent microspectral study

    International Nuclear Information System (INIS)

    Karnaukhova, N.A.; Sergiyevich, L.A.; Aksenova, G.Y.; Karnaukhov, V.N.

    1999-01-01

    The effects of different doses of acute and continuous gamma-irradiation on the synthetic activity of rat blood lymphocytes stained with acridine orange were studied by fluorescent microspectrometry. Male rats were exposed to acute gamma-irradiation with doses of 7.5, 4 and 3 Gy, or to continuous irradiation with dose rates of 14.4, 2.1, 1.1 and 0.43 cGy/day, respectively. The changes of the synthetic activity of blood lymphocytes occurred in three main stages after acute gamma-irradiation and in four stages under continuous irradiation. The stages reflect the processes of depression and activation of the immune system under irradiation. Essential differences between the acute and continuous effects were observed in the first stage. After acute gamma-irradiation, the synthetic activity decreased sharply, indicating the predominant contribution of the damaging effect of irradiation, whereas under continuous irradiation, as a result of the stimulatory effect of low-dose irradiation, the synthetic activity increased during the first stage. (orig.)

  1. The Relationship of Oxidation Sensitivity of Red Blood Cells and Carbonic Anhydrase Activity in Stored Human Blood: Effect of Certain Phenolic Compounds

    Directory of Open Access Journals (Sweden)

    Zübeyir Huyut

    2016-01-01

    Full Text Available It has been reported that many modifications occur with the increase of oxidative stress during storage in erythrocytes. In order to delay these negative changes, we evaluated whether the addition of substances likely to protect antioxidant capacity in stored blood would be useful. Therefore, we investigated the effects of resveratrol, tannic acid, and caffeic acid in lipid peroxidation and antioxidant capacity of erythrocytes in stored blood. Donated blood was taken into four CPD containing blood bags. One bag was used as the control, and the others were supplemented with caffeic acid (30 μg/mL, resveratrol (30 μg/mL, and tannic acid (15 μg/mL, respectively. Erythrocyte lipid peroxidation, sensitivity to oxidation, glutathione levels and carbonic anhydrase, glutathione peroxidase, and catalase activities were measured on days 0, 7, 14, 21, and 28. In the control group, erythrocyte malondialdehyde levels and sensitivity to oxidation were increased whereas glutathione, glutathione peroxidase, and catalase levels were decreased (p<0.05. Resveratrol and caffeic acid prevented malondialdehyde accumulation and preserved glutathione, glutathione peroxidase, and catalase activities in erythrocytes. We demonstrated that resveratrol, caffeic acid, and tannic acid in stored blood could decrease the sensitivity to oxidation of erythrocytes in vitro but did not exhibit such effects on CA activity.

  2. Bactericidal effect of colistin on planktonic Pseudomonas aeruginosa is independent of hydroxyl radical formation

    DEFF Research Database (Denmark)

    Brochmann, Rikke Prejh; Toft, Anders; Ciofu, Oana

    2014-01-01

    not require bacterial metabolic activity, we tested whether the bactericidal effect of colistin depends on the formation of OH·. In Pseudomonas aeruginosa cultures, OH-mediated killing by ciprofloxacin was demonstrated by decreased bacterial survival and induction of 3'-(p-hydroxyphenyl) fluorescein (HPF......) fluorescence. OH·-mediated killing by ciprofloxacin was further confirmed by rescue of cells and reduction of HPF fluorescence due to prevention of OH· accumulation by scavenging with thiourea, by chelating with dipyridyl, by decreasing metabolism as well as by anoxic growth. In contrast, no formation of OH...

  3. Blood parameters and enzymatic and oxidative activity in the liver of chickens fed with calcium anacardate

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Braga Cruz

    Full Text Available ABSTRACT The aim of this research was to evaluate the inclusion of calcium anacardate (CAC as a source of anacardic acid in the diet of broiler chickens on blood parameters, and enzymatic and oxidative activity in the liver. A total of 840 male chicks, one day old, were kept in a completely randomised experimental design, with six treatments and seven replications of 20 birds, totalling 140 birds per treatment. The treatments consisted of feed without the addition of growth promoter (GP, feed with GP, and feed with no GP and the addition of CAC at levels of 0.25, 0.50, 0.75 and 1%. The biochemical blood variables to be analysed were uric acid, total cholesterol, HDL, LDL, creatinine, AST, ALT, triglycerides, total erythrocytes, haemoglobin, haematocrit, mean corpuscular volume, corpuscular haemoglobin concentration, total plasma protein, total leukocytes, heterophils, lymphocytes, platelets and heterophil/lymphocyte ratio. The concentrations of superoxide dismutase, glutathione peroxidase and malondialdehyde were analysed for the enzymatic and oxidative parameters in the liver. There were no significant differences between treatments in the blood parameters or the enzymatic and oxidative activity in the liver of the chickens, demonstrating that the use of calcium anacardate as a source of anacardic acid is non-toxic, and does not affect these parameters.

  4. Blood concentrations of ions and metals in amateur and elite runners using neutron activation analyses

    International Nuclear Information System (INIS)

    Santos, Luciana Kovacs dos

    2012-01-01

    In this study Br, Ca, Cl, Fe, I, K, Mg, Na, S and Zn concentration were investigated in blood of Brazilian athletes (endurance) using Neutron Activation Analyses technique (NAA). The blood samples were collected from male amateur athletes (AR) and male and female elite athletes (ER), ranging from 18 to 36 year old. The blood samples were collected at the LABEX/UNICAMP and they were irradiated in the nuclear reactor IEA-R1 at IPEN (Sao Paulo, Brazil). The range (at rest) established for AR and ER were compared with the control group (CG), subjects of same gender and age but not involved with physical activities, and showed significant differences for Ca (51 - 439 mgL -1 for CG, 162 - 410 mgL -1 for AR and 64 - 152 mgL -1 for ER) and Br (7.4 - 30.6 mgL -1 for CG, 4.0 - 9.6 mgL -1 for AR and 1.9 - 3.5 mgL -1 for ER), suggesting that a strong dependency of these limits in function of adopted physical training exists. We also performed a systematic investigation for the AR before, during and after the exercise program. These data can be considered for the preparation of a balanced diet, for evaluating the performance of the athletes during the period of competition preparation as well as contributing for proposing new protocols of clinical evaluation not reported in the literature yet. (author)

  5. In vitro detection and quantification of botulinum neurotoxin type E activity in avian blood

    Science.gov (United States)

    Piazza, Timothy M.; Blehert, David S.; Dunning, F. Mark; Berlowski-Zier, Brenda M.; Zeytin, Fusun N.; Samuel, Michael D.; Tucker, Ward C.

    2011-01-01

    Botulinum neurotoxin serotype E (BoNT/E) outbreaks in the Great Lakes region cause large annual avian mortality events, with an estimated 17,000 bird deaths reported in 2007 alone. During an outbreak investigation, blood collected from bird carcasses is tested for the presence of BoNT/E using the mouse lethality assay. While sensitive, this method is labor-intensive and low throughput and can take up to 7 days to complete. We developed a rapid and sensitive in vitro assay, the BoTest Matrix E assay, that combines immunoprecipitation with high-affinity endopeptidase activity detection by Förster resonance energy transfer (FRET) to rapidly quantify BoNT/E activity in avian blood with detection limits comparable to those of the mouse lethality assay. On the basis of the analysis of archived blood samples (n = 87) collected from bird carcasses during avian mortality investigations, BoTest Matrix E detected picomolar quantities of BoNT/E following a 2-h incubation and femtomolar quantities of BoNT/E following extended incubation (24 h) with 100% diagnostic specificity and 91% diagnostic sensitivity.

  6. Feto-maternal interactions in pregnancies: placental microparticles activate peripheral blood monocytes.

    Science.gov (United States)

    Messerli, M; May, K; Hansson, S R; Schneider, H; Holzgreve, W; Hahn, S; Rusterholz, C

    2010-02-01

    Normal pregnancy is associated with a systemic maternal inflammatory reaction, including the activation of peripheral blood monocytes. This reaction is exaggerated in pre-eclampsia, a severe placenta-dependent disorder of pregnancy specific to humans. It has been suggested that placental syncytiotrophoblast membrane microparticles (STBM), which are released into the peripheral blood, may contribute to the maternal response. The aim of this study was to investigate the inflammatory properties of STBM generated by four different approaches on primary human monocytes in vitro. Cellular viability, phenotype and functional response were analysed. STBM isolated by mechanical dissection and STBM generated from villous explant cultures incubated in hypoxic conditions had only minor influences on the monocytic phenotype and failed to induce a proinflammatory response. By contrast, STBM washed from the maternal side of a placental cotyledon and STBM shed by explants cultured in air up-regulated cell surface expression of the adhesion molecule CD54 and induced the production of interleukin (IL)-8, IL-6 and IL-1beta. Cytokine production was time- and dose-dependent. Our study, therefore, suggests that monocyte activation in normal pregnancy and pre-eclampsia may be induced by STBM released by the placenta. The higher amounts of STBM circulating in maternal blood in pre-eclampsia might lead to the excessive maternal inflammatory reaction. 2009 Elsevier Ltd. All rights reserved.

  7. Cardiovascular activity in blood-injection-injury phobia during exposure: evidence for diphasic response patterns?

    Science.gov (United States)

    Ritz, Thomas; Meuret, Alicia E; Simon, Erica

    2013-08-01

    Exposure to feared stimuli in blood-injection-injury (BII)-phobia is thought to elicit a diphasic response pattern, with an initial fight-flight-like cardiovascular activation followed by a marked deactivation and possible fainting (vasovagal syncope). However, studies have remained equivocal on the importance of such patterns. We therefore sought to determine the prevalence and clinical relevance of diphasic responses using criteria that require a true diphasic response to exceed cardiovascular activation of an emotional episode of a negative valence and to exceed deactivation of an emotionally neutral episode. Sixty BII-phobia participants and 20 healthy controls were exposed to surgery, anger and neutral films while measuring heart rate, blood pressure, respiratory pattern, and end-tidal partial pressure of carbon dioxide (as indicator of hyperventilation). Diphasic response patterns were observed in up to 20% of BII-phobia participants and 26.6% of healthy controls for individual cardiovascular parameters. BII-phobia participants with diphasic patterns across multiple parameters showed more fear of injections and blood draws, reported the strongest physical symptoms during the surgery film, and showed the strongest tendency to hyperventilate. Thus, although only a minority of individuals with BII phobia shows diphasic responses, their occurrence indicates significant distress. Respiratory training may add to the treatment of BII phobia patients that show diphasic response patterns. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. The location of splenic NKT cells favours their rapid activation by blood-borne antigen

    Science.gov (United States)

    Barral, Patricia; Sánchez-Niño, María Dolores; van Rooijen, Nico; Cerundolo, Vincenzo; Batista, Facundo D

    2012-01-01

    Natural killer T (NKT) cells play an important role in mounting protective responses to blood-borne infections. However, though the spleen is the largest blood filter in the body, the distribution and dynamics of NKT cells within this organ are not well characterized. Here we show that the majority of NKT cells patrol around the marginal zone (MZ) and red pulp (RP) of the spleen. In response to lipid antigen, these NKT cells become arrested and rapidly produce cytokines, while the small proportion of NKT cells located in the white pulp (WP) exhibit limited activation. Importantly, disruption of the splenic MZ by chemical or genetic approaches results in a severe reduction in NKT cell activation indicating the need of cooperation between both MZ macrophages and dendritic cells for efficient NKT cell responses. Thus, the location of splenic NKT cells in the MZ and RP facilitates their access to blood-borne antigen and enables the rapid initiation of protective immune responses. PMID:22505026

  9. Vitamin D(3 availability and functional activity of peripheral blood phagocytes in experimental type 1 diabetes

    Directory of Open Access Journals (Sweden)

    D. О. Labudzynskyi

    2014-04-01

    Full Text Available The study was devoted to identifying the relation between vitamin D3 availability (assessed by the level of circulatory 25OHD3, content of vitamin D3 25-hydroxylase isozymes CYP27A1 and CYP2R1 in hepatic tissue and functional activity of peripheral blood phagocytes in mice with experimental type 1 diabetes. It has been shown that diabetes is accompanied by the development of vitamin D3-deficiency which is characterized by decreased 25OHD3 content in blood serum and determined by changes in tissue expression of the major isoforms of vitamin D3 25-hydroxylase. The level of hepatic CYP27A1 was revealed to be markedly reduced with a concurrent significant augmentation of CYP2R1. Cholecalciferol administration resulted in normalization of tissue levels of both isoforms of vitamin D3 25-hydroxylase and blood serum 25OHD3 content. Diabetes-associated vitamin D3 deficiency correlated with a decrease in phagocytic activity of granulocytes and monocytes, and their ability to produce antibacterial biooxidants such as reactive oxygen and nitrogen forms. Vitamin D3 efficacy to attenuate these abnormalities of immune function was established, indicating an important immunoregulatory role of cholecalciferol in the phagocytic mechanism of antigens elimination implemented by granulocytes and monocytes.

  10. Adiposity, physical activity and blood lipid profile in 13-year-old adolescents.

    Science.gov (United States)

    Ostojic, Sergej M; Stojanovic, Marko; Stojanovic, Vladan; Maric, Jelena

    2010-04-01

    The main aim of this study was to determine the extent to which physical activity and adiposity are associated with blood cholesterol levels in male adolescents. Anthropometric and physical fitness values were measured in all children. Body mass index (BMI) and physical activity index (PAI) were used to split participants into active overweight (ACO) and non-active normal-weight (NAN) groups. The cutoffs for the ACO group were BMI > or = 22.6 kg/m2 and PAI > or = 3.5, respectively, whereas the corresponding cutoffs for the NAN groups were BMI body fat as compared to their NAN counterparts (p HDL-cholesterol was higher in ACO group (p correlation between HDL-cholesterol and PAI in ACO group (r = 0.38; p index explained the majority of variance in HDL-cholesterol for ACO group (beta = 0.513; p adiposity per se, particularly for HDL-cholesterol.

  11. Pituitary adenylate cyclase-activating polypeptide (PACAP) in fetal cord blood.

    Science.gov (United States)

    Winters, Stephen J; King, Jeffrey C; Brees, Carol K; Moore, Joseph P

    2014-09-01

    Pituitary adenylate cyclase-activating peptide (PACAP) is a centrally-acting peptide with highest concentration within the limbic area of the brain. PACAP is also expressed in and affects the functions of vascular and nervous tissues, endocrine glands, and the placenta. PACAP appears to be associated with the 'fight-or-flight' response to emergency partly through its effect on adrenal production of cortisol and catecholamines. We sought to explore the impact of labor as a stressor on the level of PACAP in the fetus, and hypothesized that PACAP levels would be increased when labor, abnormal fetal heart tracing, or fetal growth impairment was evident. Fetal cord venous blood samples were collected immediately after delivery from a random group of women undergoing either vaginal or Cesarean delivery. The blood was placed in chilled EDTA-aprotinin containing tubes, centrifuged, and stored at -80°C for PACAP immunoassay. Delivery data were abstracted for analysis. The level of PACAP in cord blood was similar in both males and females. There was a trend toward higher levels in the cord blood of fetuses delivered by Cesarean compared to those delivered vaginally. PACAP levels were unrelated to birth weight, Apgar scores, and the presence or absence of labor prior to delivery. While PACAP and its receptor are expressed in placenta, and PACAP protein is found in cord blood, no effect of labor stress on PACAP was found. Further research is needed to understand the role of PACAP in gestation and parturition. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. The effects of the bacterial interaction with visible-light responsive titania photocatalyst on the bactericidal performance

    Directory of Open Access Journals (Sweden)

    Cheng Chia-Liang

    2009-01-01

    Full Text Available Abstract Bactericidal activity of traditional titanium dioxide (TiO2 photocatalyst is effective only upon irradiation by ultraviolet light, which restricts the potential applications of TiO2 for use in our living environments. Recently carbon-containing TiO2 was found to be photoactive at visible-light illumination that affords the potential to overcome this problem; although, the bactericidal activity of these photocatalysts is relatively lower than conventional disinfectants. Evidenced from scanning electron microscopy and confocal Raman spectral mapping analysis, we found the interaction with bacteria was significantly enhanced in these anatase/rutile mixed-phase carbon-containing TiO2. Bacteria-killing experiments indicate that a significantly higher proportion of all tested pathogens including Staphylococcus aureus, Shigella flexneri and Acinetobacter baumannii, were eliminated by the new nanoparticle with higher bacterial interaction property. These findings suggest the created materials with high bacterial interaction ability might be a useful strategy to improve the antimicrobial activity of visible-light-activated TiO2.

  13. Blood coagulation parameters and activity indices in patients with systemic lupus erythematosus

    Directory of Open Access Journals (Sweden)

    A. A. Arshinov

    2005-01-01

    Full Text Available Objective. To assess coagulation parameters and activity indices in pts with systemic lupus erythematosus (SLE. Material and methods . 86 pts with SLE (83 female and 3 male were examined. 12 of them had antiphospholipid syndrome. Mean age was 35,9±1,5 years (from 18 to 58 years, mean disease duration was 9,8+1,4 years. Control group consisted of 60 healthy volunteers with mean age 37,1+4,1 years. SLE activity assessment was performed with SLAM, SLEDAI and ECLAM indices. Results. SLE pts showed 5-fold (p<0,01 increase of spontaneous platelets aggregation and more than 3-fold increase of factor von Willebrand antigen (FWA concentration. Platelet activation in pts was accompanied by decrease of platelet aggregation with collagen (on 27%, p<0,01. Characteristic sign of coagulation hemostasis activation was significant increase of soluble fibrin-monomer complexes (SFMC concentration on 81 % (p<0,01 so as increase D-dimers level in 53,3% of pts. Fibrinogen concentration was increased on 29%, spontaneous fibrinolysis parameters were decreased on 20%, antithrombin (AT 111 - on 21% in comparison with control. Direct correlation between activity indiccs and SFMC(ECLAM, r=0,5, fibrinogen concentration (SLAM, r=0,34, D- dimers level (ECLAM, r=0,5, spontaneous platelet aggregation (ECLAM, r=0,5 so as inverse correlation with AT III activity (SLEDAI, r-0,73 was revealed. Conclusion. Changes of hemostasis parameters in SLE may serve as predictors of thrombotic disorders development and indication to drug correction of blood coagulation disorders. Direct correlation between blood coagulation system activity and indices of SLE activity.

  14. Blood Fibrinolytic Activity in Patients with Type 2 Diabetes Mellitus Associated with Hypothyroidism

    Directory of Open Access Journals (Sweden)

    Т.Yu. Yuzvenko

    2015-04-01

    Full Text Available The objective of the research was to study the level of plasminogen activator inhibitor type 1 (PAI-1 in the blood serum of patients with type 2 diabetes mellitus (DM in combination with hypothyroidism. We have observed 62 patients with type 2 DM, 32 of them had primary hypothyroidism. Control group consisted of 20 persons without carbohydrate metabolism disorders and thyroid pathology. In patients with type 2 DM, we have detected violations in the fibrinolytic system as an increase of PAI-1, whose level depends on the body mass index, waist circumference, level of glycated haemoglobin, indexes of insulin resistance, blood lipid spectrum, as well as on the presence of microalbuminuria. The presence of hypothyroidism has an additional negative impact on the parameters of carbohydrate, lipid metabolism and PAI-1 level in patients with type 2 DM.

  15. Bactericidal effects of 310?nm ultraviolet light-emitting diode irradiation on oral bacteria

    OpenAIRE

    Takada, Ayuko; Matsushita, Kenji; Horioka, Satoru; Furuichi, Yasushi; Sumi, Yasunori

    2017-01-01

    Background Ultraviolet (UV) light is used for phototherapy in dermatology, and UVB light (around 310?nm) is effective for treatment of psoriasis and atopic dermatitis. In addition, it is known that UVC light (around 265?nm) has a bactericidal effect, but little is known about the bactericidal effect of UVB light. In this study, we examined the bactericidal effects of UVB-light emitting diode (LED) irradiation on oral bacteria to explore the possibility of using a 310?nm UVB-LED irradiation de...

  16. Rapid Detection of Thrombin and Other Protease Activity Directly in Whole Blood

    Science.gov (United States)

    Yu, Johnson Chung Sing

    Thrombin is a serine protease that plays a key role in the clotting cascade to promote hemostasis following injury to the endothelium. From a clinical diagnostic perspective, in-vivo thrombin activity is linked to various blood clotting disorders, as well as cardiovascular disease (DVT, arteriosclerosis, etc). Thus, the ability to rapidly measure protease activity directly in whole blood will provide important new diagnostics, and clinical researchers with a powerful tool to further elucidate the relationship between circulating protease levels and disease. The ultimate goal is to design novel point of care (POC) diagnostic devices that are capable of monitoring protease activities directly in whole blood and biological sample. A charge-changing substrate specific to the thrombin enzyme was engineered and its functionality was confirmed by a series of experiments. This led to the preliminary design, construction, and testing of two device platforms deemed fully functional for the electrophoretic separation and focusing of charged peptide fragments. The concept of using the existing charge-changing substrate platform for bacterial protease detection was also investigated. Certain strains of E coli are associated with severe symptoms such as abdominal cramps, bloody diarrhea, and vomiting. The OmpT protease is expressed on the outer membrane of E coli and plays a role in the cleavage of antimicrobial peptides, the degradation of recombinant heterologous proteins, and the activation of plasminogen in the host. Thus, a synthetic peptide substrate specific to the OmpT protease was designed and modeled for the purpose of detecting E coli in biological sample.

  17. Contact activation of blood coagulation on a defined kaolin/collagen surface in a microfluidic assay.

    Science.gov (United States)

    Zhu, Shu; Diamond, Scott L

    2014-12-01

    Generation of active Factor XII (FXIIa) triggers blood clotting on artificial surfaces and may also enhance intravascular thrombosis. We developed a patterned kaolin (0 to 0.3 pg/μm(2))/type 1 collagen fibril surface for controlled microfluidic clotting assays. Perfusion of whole blood (treated only with a low level of 4 μg/mL of the XIIa inhibitor, corn trypsin inhibitor) drove platelet deposition followed by fibrin formation. At venous wall shear rate (100 s(-1)), kaolin accelerated onset of fibrin formation by ~100 sec when compared to collagen alone (250 sec vs. 350 sec), with little effect on platelet deposition. Even with kaolin present, arterial wall shear rate (1000 s(-1)) delayed and suppressed fibrin formation compared to venous wall shear rate. A comparison of surfaces for extrinsic activation (tissue factor TF/collagen) versus contact activation (kaolin/collagen) that each generated equal platelet deposition at 100 s(-1) revealed: (1) TF surfaces promoted much faster fibrin onset (at 100 sec) and more endpoint fibrin at 600 sec at either 100 s(-1) or 1000 s(-1), and (2) kaolin and TF surfaces had a similar sensitivity for reduced fibrin deposition at 1000 s(-1) (compared to fibrin formed at 100 s(-1)) despite differing coagulation triggers. Anti-platelet drugs inhibiting P2Y1, P2Y12, cyclooxygenase-1 or activating IP-receptor or guanylate cyclase reduced platelet and fibrin deposition on kaolin/collagen. Since FXIIa or FXIa inhibition may offer safe antithrombotic therapy, especially for biomaterial thrombosis, these defined collagen/kaolin surfaces may prove useful in drug screening tests or in clinical diagnostic assays of blood under flow conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Odors generated from the Maillard reaction affect autonomic nervous activity and decrease blood pressure through the olfactory system.

    Science.gov (United States)

    Zhou, Lanxi; Ohata, Motoko; Owashi, Chisato; Nagai, Katsuya; Yokoyama, Issei; Arihara, Keizo

    2018-02-01

    Systolic blood pressure (SBP) of rats decreases significantly following exposure to the odor generated from the Maillard reaction of protein digests with xylose. This study identified active odorants that affect blood pressure and demonstrated the mechanism of action. Among the four potent odorants that contribute most to the odor of the Maillard reaction sample, 2,5-dimethyl-4-hydroxy-3(2H)-furanone (DMHF) and 5-methyl-2-pyrazinemethanol (MPM) decreased SBP significantly. The earliest decrease in blood pressure was observed 5 min after exposure to DMHF. Application of zinc sulfate to the nasal cavity eliminated the effect. Furthermore, gastric vagal (parasympathetic) nerve activity was elevated and renal sympathetic nerve activity was lowered after exposure to DMHF. It is indicated that DMHF affects blood pressure through the olfactory system, and the mechanism for the effect of DMHF on blood pressure involves the autonomic nervous system. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  19. Neutron activation analysis of Cl, K and Na content in whole blood of horses used in hyperimmune sera production

    International Nuclear Information System (INIS)

    Baptista, T.S.; Zamboni, C.B.; Medeiros, J.A.G.; Freitas, M.G.; Higashi, H.G.; Marcelino, J.R.

    2009-01-01

    Using neutron activation analysis technique Cl, K and Na concentration were obtained in whole blood of equines used for antivenom production at Butantan Institute (Sao Paulo, Brazil). These data were compared with the human whole blood estimation. No significant difference was observed suggesting that this model animal is adequate sera production. (author)

  20. Immobilized silver nanoparticles enhance contact killing and show highest efficacy: elucidation of the mechanism of bactericidal action of silver

    Science.gov (United States)

    Agnihotri, Shekhar; Mukherji, Soumyo; Mukherji, Suparna

    2013-07-01

    Antimicrobial materials with immobilized/entrapped silver nanoparticles (AgNPs) are of considerable interest. There is significant debate on the mode of bactericidal action of AgNPs, and both contact killing and/or ion mediated killing have been proposed. In this study, AgNPs were immobilized on an amine-functionalized silica surface and their bactericidal activity was studied concurrently with the silver release profile over time. This was compared with similar studies performed using colloidal AgNPs and AgCl surfaces that released Ag ions. We conclude that contact killing is the predominant bactericidal mechanism and surface immobilized nanoparticles show greater efficacy than colloidal AgNPs, as well as a higher concentration of silver ions in solution. In addition, the AgNP immobilized substrate was used multiple times with good efficacy, indicating this immobilization protocol is effective for retaining AgNPs while maintaining their disinfection potential. The antibacterial surface was found to be extremely stable in aqueous medium and no significant leaching (~1.15% of total silver deposited) of the AgNPs was observed. Thus, immobilization of AgNPs on a surface may promote reuse, reduce environmental risks associated with leaching of AgNPs and enhance cost effectiveness.Antimicrobial materials with immobilized/entrapped silver nanoparticles (AgNPs) are of considerable interest. There is significant debate on the mode of bactericidal action of AgNPs, and both contact killing and/or ion mediated killing have been proposed. In this study, AgNPs were immobilized on an amine-functionalized silica surface and their bactericidal activity was studied concurrently with the silver release profile over time. This was compared with similar studies performed using colloidal AgNPs and AgCl surfaces that released Ag ions. We conclude that contact killing is the predominant bactericidal mechanism and surface immobilized nanoparticles show greater efficacy than colloidal Ag

  1. Longer repetition duration increases muscle activation and blood lactate response in matched resistance training protocols

    Directory of Open Access Journals (Sweden)

    Hugo Cesar Martins-Costa

    2016-03-01

    Full Text Available Abstract This study analyzed the effect of different repetition durations on electromyographic and blood lactate responses of the bench press exercise. Fifteen recreationally trained male volunteers completed two training protocols, matched for intensity (% one-repetition maximum; 1RM, number of sets, number of repetitions, and rest intervals. One of the protocols was performed with a repetition duration of 4 s (2 s concentric: 2 s eccentric; 2:2 protocol, whereas the second protocol had a repetition duration of 6 s (2 s concentric: 4 s eccentric; 2:4 protocol. The results showed higher normalized integrated electromyography (pectoralis major and triceps brachii for the 2:4 protocol. Blood lactate concentration was also higher in the 2:4 protocol across all sets. These results show that adding 2 s to the eccentric action in matched training protocols increases muscle activation and blood lactate response, which reinforces the notion that increasing repetition duration is an alternative load progression in resistance training.

  2. Effectiveness of physical activity promotion in blood pressure and blood sugar reduction: A community-based intervention study in rural south India

    Directory of Open Access Journals (Sweden)

    Subitha Lakshminarayanan

    2012-01-01

    Full Text Available Context: Physical activity of moderate intensity for 30 minutes a day, on most days substantially reduces the risk of many chronic diseases. Aim: To assess the effect of regular physical activity on blood pressure and blood sugar levels in a rural Indian community Settings and Design: This community-based study was carried out in Periakattupalayam and Rangareddipalayam in south India, with 485 subjects, aged 20 to 49 years. Materials and Methods: The study was done in five phases: Awareness campaign, baseline assessment of participants, intervention phase (10 weeks, interim, and final assessment. Physical activity of moderate intensity (brisk walking for 30 minutes on four days / week was promoted by forming 30 small walking groups, in a home-based setting, with professional supervision. Village leaders and Self-Help Group members were the resource people for the promotion of physical activity. Statistical Analysis: Analysis was done by using paired ′t′ test; the ′Intention-to-Treat′ approach was utilized for the interpretation of the findings of the study. Results: Of the 485 subjects, 265 (54.6% complied with walking on more than four days / week, while 156 (32.2% walked on one to four days / week, and 64 (13.2% dropped out during the intervention period. This study has shown that a 10-week intervention to promote physical activity was effective in significantly decreasing the population′s BP by 1.56 / 0.74 mm Hg, fasting blood sugar levels by 2.82 mg%, body weight by 0.17 kg, and BMI by 0.06 kg / m 2 . Conclusions: This study has proved the functional feasibility of enabling people to undertake physical activity in a rural Indian community, and the effectiveness of using physical activity, to significantly reduce the population′s mean BP and blood sugar levels.

  3. Effects of dietary fat quality and quantity on postprandial activation of blood coagulation factor VII

    DEFF Research Database (Denmark)

    Larsen, L F; Bladbjerg, E-M; Jespersen, J

    1997-01-01

    , palm oil, or butter (42% of energy from fat) or isoenergetic low-fat meals (6% of energy from fat). Fasting and series of nonfasting blood samples (the last at time 8 1/2 hours) were collected. Plasma triglycerides, FVIIc, FVIIa, and free fatty acids were analyzed. There were marked effects of the fat......, monounsaturated, or polyunsaturated fats differed regarding postprandial activation of FVII. Eighteen healthy young men participated in the study. On 6 separate days each participant consumed two meals (times, 0 and 1 3/4 hours) enriched with 70 g (15 and 55 g) of either rapeseed oil, olive oil, sunflower oil...

  4. Trace element analysis of human blood serum by neutron activation analysis

    International Nuclear Information System (INIS)

    Nakahara, H.; Nagame, Y.; Yoshizawa, Y.; Oda, H.; Gotoh, S.; Murakami, Y.

    1979-01-01

    An attempt was made to determine if there is any correlation between trace element concentrations in human blood serum and some specific diseases. The serum samples of the patients suffering from cancer, Down syndrome, and Banti syndrome were analyzed by the neutron activation method and compared with the trace element concentrations observed among clinically healthy men. The cancer patients had concentrations in Rb, Mn, Fe, Co, Cu, Zn, Al and Se below normal. The Down syndrome patients were found to have similar deficiencies in Cr, Mn, Fe, Co, Zn, Cu and Sb. (author)

  5. Regional cerebral blood flow in psychiatry: The resting and activated brains of schizophrenic patients

    International Nuclear Information System (INIS)

    Gur, R.E.

    1984-01-01

    The investigation of regional brain functioning in schizophrenia has been based on behavioral techniques. Although results are sometimes inconsistent, the behavioral observations suggest left hemispheric dysfunction and left hemispheric overreaction. Recent developments in neuroimaging technology make possible major refinements in assessing regional brain function. Both anatomical and physiological information now be used to study regional brain development in psychiatric disorders. This chapter describes the application of one method - the xenon-133 technique for measuring regional cerebral blood flow (rCBF) - in studying the resting and activated brains of schizoprenic patients

  6. The feed gas composition determines the degree of physical plasma-induced platelet activation for blood coagulation

    Science.gov (United States)

    Bekeschus, Sander; Brüggemeier, Janik; Hackbarth, Christine; Weltmann, Klaus-Dieter; von Woedtke, Thomas; Partecke, Lars-Ivo; van der Linde, Julia

    2018-03-01

    Cold atmospheric (physical) plasma has long been suggested to be a useful tool for blood coagulation. However, the clinical applicability of this approach has not been addressed sufficiently. We have previously demonstrated the ability of a clinically accepted atmospheric pressure argon plasma jet (kINPen® MED) to coagulate liver incisions in mice with similar performance compared to the gold standard electrocauterization. We could show that plasma-mediated blood coagulation was dependent on platelet activation. In the present work, we extended on this by investigating kINPen®-mediated platelet activation in anticoagulated human donor blood ex vivo. With focus on establishing high-throughput, multi-parametric platelet activation assays and performing argon feed gas parameter studies we achieved the following results: (i) plasma activated platelets in heparinized but not in EDTA-anticoagulated blood; (ii) plasma decreased total platelet counts but increased numbers of microparticles; (iii) plasma elevated the expression of several surface activation markers on platelets (CD62P, CD63, CD69, and CD41/61); (iv) in platelet activation, wet and dry argon plasma outperformed feed gas admixtures with oxygen and/or nitrogen; (v) plasma-mediated platelet activation was accompanied by platelet aggregation. Platelet aggregation is a necessary requirement for blood clot formation. These findings are important to further elucidate molecular details and clinical feasibility of cold physical plasma-mediated blood coagulation.

  7. Bactericidal effect of Nd:YAG laser irradiation in endodontics

    Science.gov (United States)

    Aun, Carlos E.; Barberini, Alexandre F.; Camargo, Selma C. C.; Silva Kfouri, Luciana; Lorenzetti Simionato, Maria R.

    1999-05-01

    The success of endodontic therapy is based on the elimination of bacterial colonization from the endodontic system and periapical tissues. Recent studies have been showing the bactericidal effect of laser in root canal treatment. The propose of the study is to evaluate the effect of Nd:YAG laser irradiation in contaminated root canal treatment. The propose of the study is to evaluate the effect of Nd:YAG laser irradiation in contaminated root canals from upper central incisor. For the experiment 12 teeth were selected, respect at the apical third, sterilized, and 10 μm Streptococcus sanguis liquid culture were inoculated in the root canals. The laser test groups were irradiated with Nd:YAG laser at standard setting of 15Hz, 100mj and 1,5 W for 10, 20 and 30 seconds each in slow helicoidal movements from the apex to the top using a 300 micrometers fiber. After the procedure the specimens were placed in Tryptic Soy Agar, the number of colony forming units was evaluated. The experiment showed a significant reduction on viability of Streptococcus sanguis at the respective time of 20 and 30 seconds.

  8. Null bactericidal effect of ultraviolet radiation emitted by LEDs.

    Directory of Open Access Journals (Sweden)

    Francisco Alcántara Muñoz

    2016-11-01

    Full Text Available This research has aimed to assess the bactericidal effect of ultraviolet light emitted by LEDS on the growth on Petri dishes of microorganisms whose legal limits in foods have been established. An electrically fed apparatus has been designed with precise timing and a camera to prevent light spillage, in which two ultraviolet radiation emission devices were connected by LED technology at different wavelengths: through an array of LEDS emitting at around 350nm, and a single specific emission LED at 280nm. 1000 cfu of E. Coli and S. aureus sown on PCA were used as prototypes of gram negative and positive bacteria, respectively, onto which ultraviolet light was radiated at different time intervals, by means of both devices, with the whole experiment being carried out in triplicate . In none of the three series of treatments at the two wavelengths were reductions in microbial growth observed. The series of sowings on PCA were done on unseeded plates in order to be able to discard the likelihood of subsequent recontamination.

  9. Effects of contact time and concentration on bactericidal efficacy of 3 disinfectants on hard nonporous surfaces.

    Science.gov (United States)

    Hong, Yingying; Teska, Peter J; Oliver, Haley F

    2017-11-01

    This study investigated the influence of contact time and concentration on bactericidal efficacy of 3 types of disinfectants (accelerated hydrogen peroxide [AHP], quaternary ammonium compounds [Quats], and sodium hypochlorite) on stainless steel surfaces using Environmental Protection Agency procedure MB-25-02. We found that bactericidal efficacy was not reduced at contact times or concentrations immediate lower than label use values, but all 3 disinfectants were significantly less bactericidal at significantly lower than label use contact times and concentrations. Overall, the bactericidal efficacy of the sodium hypochlorite disinfectant was most tolerant to the decreases of contact times and concentrations, followed closely by AHP disinfectant, and Quat disinfectant was most affected by contact time and concentration. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  10. Bactericidal effect of starch-stabilized zero-valent iron nanoparticles on Escherichia coli

    Directory of Open Access Journals (Sweden)

    Mohammad Mosaferi

    2016-01-01

    Conclusion: The present study showed that nonstabilized Fe 0 nanoparticles have higher bactericidal efficiency than that of S-NZVI. This investigation also suggests that NZVI can be used as an effective and strong agent for antimicrobial applications.

  11. Comparative opsonic activity for Steptococcus mutans in oral fluids, and phagocytic activity of blood, crevicular, and salivary polymorphonuclear leucocytes in rhesus monkeys.

    Science.gov (United States)

    Scully, C M

    1980-01-01

    The opsonic activity for Streptococcus mutans was assayed in serum, gingival crevicular fluid, parotid saliva and mixed saliva from rhesus monkeys immunized against dental caries with a vaccine of Streptococcus mutans in Freund's incomplete adjuvant. The phagocytic activities of polymorphonuclear leucocytes from the blood and gingival crevice were compared, and the effects of gingival crevicular fluid and mixed saliva on blood polymorphonuclear leucocyte viability and phagocytic activity were assessed. Heat-stable opsonic activity was detected in sera, crevicular fluid, and mixed saliva of immunized animals. Polymorphonuclear leucocytes from the gingival crevice and saliva retained viability, although this was lower than in cells from blood. Exposure of blood polymorphonuclear leucocytes to crevicular fluid or mixed saliva for 30 min resulted in no loss of cell viability or phagocytic activity, but saliva was cytotoxic on prolonged exposure. These results support the hypothesis that the opsonization and phagocytosis of cariogenic bacteria might be a mechanism involved in the immunological protection against dental caries.

  12. Blood Lead Level and Δ-Aminolevulinic Acid Dehydratase Activity in Pre-Menopausal and Postmenopausal Women

    Directory of Open Access Journals (Sweden)

    I.R Elezaj

    2012-07-01

    Full Text Available To describe the relationship of blood lead levels (BLL and blood, δ-aminolevulinic acid dehydratase(ALAD activity and haematocrit value(Hct to menopause , were examined 17 pre-or perimenopausal (PreM and 17 postmenopausal women (PosMfrom Prishtina City, the capital ofRepublic Kosovo. The mean age of the PreM women was 28.8 years (21-46, with a mean blood lead level of 1.2 μg/dL (SD=0.583 μg/dL , the mean blood ALAD activity53.2 U/LE (SD= 2.8 U/LE and haematocrit value42.1 % (SD= 4.3 %. The mean age of the PosM women was 53.6 years (43-67, with a mean blood lead level1.9 μg/dL (SD=0.94 μg/dL, the mean blood ALAD activity 44.4 U/LE(SD=7.2 U/LE and haematocrit value 42.1 % ( SD= 4.3 % and 42.2 % (SD=4.4 %. The BPb level of PosM women was significantly higher (P<0.001 in comparison with the BPb level in PreM women. The blood ALAD activity of PosM was significantly inhibited (P<0.002 in comparison with blood ALAD activity in PreM women. The haematocrit values were relatively unchanged. There was established significantly negative correlation between BPb and blood ALAD activity (r=- 0.605; P<0.01 in the PreM women.These results support the hypothesis that release of bone lead stores increases during menopause and constitutes an internal source of exposure possibly associated with adverse health effects on women in menopause transition.

  13. Misread protein creates membrane channels: an essential step in the bactericidal action of aminoglycosides.

    OpenAIRE

    Davis, B D; Chen, L L; Tai, P C

    1986-01-01

    Among the pleiotropic effects of aminoglycosides, their irreversible uptake and their blockade of initiating ribosomes have appeared to explain their bactericidal action, while the contributions of translational misreading and membrane damage and the mechanism of that damage have remained uncertain. We now present evidence that incorporation of misread proteins into the membrane can account for the membrane damage. The bactericidal action thus appears to result from the following sequence, in...

  14. A generic mechanism in Neisseria meningitidis for enhanced resistance against bactericidal antibodies

    OpenAIRE

    Uria, Maria Jose; Zhang, Qian; Li, Yanwen; Chan, Angel; Exley, Rachel M.; Gollan, Bridget; Chan, Hannah; Feavers, Ian; Yarwood, Andy; Abad, Raquel; Borrow, Ray; Fleck, Roland A.; Mulloy, Barbara; Vazquez, Julio A.; Tang, Christoph M.

    2008-01-01

    The presence of serum bactericidal antibodies is a proven correlate of protection against systemic infection with the important human pathogen Neisseria meningitidis. We have identified three serogroup C N. meningitidis (MenC) isolates recovered from patients with invasive meningococcal disease that resist killing by bactericidal antibodies induced by the MenC conjugate vaccine. None of the patients had received the vaccine, which has been successfully introduced in countries in North America...

  15. Secreted aspartic peptidases of Candida albicans liberate bactericidal hemocidins from human hemoglobin.

    Science.gov (United States)

    Bocheńska, Oliwia; Rąpała-Kozik, Maria; Wolak, Natalia; Braś, Grażyna; Kozik, Andrzej; Dubin, Adam; Aoki, Wataru; Ueda, Mitsuyoshi; Mak, Paweł

    2013-10-01

    Secreted aspartic peptidases (Saps) are a group of ten acidic hydrolases considered as key virulence factors of Candida albicans. These enzymes supply the fungus with nutrient amino acids as well as are able to degrade the selected host's proteins involved in the immune defense. Our previous studies showed that the human menstrual discharge is exceptionally rich in bactericidal hemoglobin (Hb) fragments - hemocidins. However, to date, the genesis of such peptides is unclear. The presented study demonstrates that the action of C. albicans isozymes Sap1-Sap6, Sap8 and Sap9, but not Sap7 and Sap10, toward human hemoglobin leads to limited proteolysis of this protein and generates a variety of antimicrobial hemocidins. We have identified these peptides and checked their activity against selected microorganisms representative for human vagina. We have also demonstrated that the process of Hb hydrolysis is most effective at pH 4.0, characteristic for vagina, and the liberated peptides showed pronounced killing activity toward Lactobacillus acidophilus, and to a lower degree, Escherichia coli. However, only a very weak activity toward Staphylococcus aureus and C. albicans was noticed. These findings provide interesting new insights into pathophysiology of human vaginal candidiasis and suggest that C. albicans may be able to compete with the other microorganisms of the same physiological niche using the microbicidal peptides generated from the host protein. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. The study of cellulosic fabrics impregnated with porphyrin compounds for use as photo-bactericidal polymers

    Energy Technology Data Exchange (ETDEWEB)

    Rahimi, Rahmatollah, E-mail: rahimi_rah@iust.ac.ir [Bioinorganic Chemistry Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran 16846-13114 (Iran, Islamic Republic of); Fayyaz, Fatemeh [Bioinorganic Chemistry Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran 16846-13114 (Iran, Islamic Republic of); Rassa, Mehdi [Department of Biology, Faculty of Science, University of Guilan, Rasht (Iran, Islamic Republic of)

    2016-02-01

    In the present work, we report on the preparation of cellulosic fabrics bearing two types of photo-sensitizers in order to prepare efficient polymeric materials for antimicrobial applications. The obtained porphyrin-grafted cellulosic fabrics were characterized by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, diffuse reflectance UV–Vis (DRUV) spectroscopy, thermo-gravimetric analysis (TG) and scanning electron microscopy (SEM). Antimicrobial activity of the prepared porphyrin-cellulose was tested under visible light irradiation against Staphylococcus aureus, Pseudomunas aeroginosa and Escherichia coli. In addition, the effect of two parameters on photo-bactericidal activity of treated fibers was studied: illumination time and concentration of photosensitizers (PS). - Highlights: • Cellulosic fabrics were impregnated with various concentrations of porphyrins (TAPP and its zinc ion complex). • The products were characterized by ATR-FTIR, DRUV, SEM and TG. • The photo-antibacterial activity of products was determined against S. aureus, P. aeroginosa and E. coli. • The effect of two parameters were studied on photoinactivation of treated fibers: illumination time and concentration of PS.

  17. Influence of physical and emotional activity on the metabolic profile of blood serum of race horses

    Directory of Open Access Journals (Sweden)

    T. I. Bayeva

    2016-09-01

    Full Text Available In the article data are presented on dynamics of the level of indicators of metabolic profile of blood serum of race horses of the Ukrainian riding breed in the conditions of physical and emotional loading. Clinically healthy race horses were the object of  research. Blood was taken from the jugular vein to obtain serum and for further biochemical research. For the research 12 race horses from a training group were chosen. From time to time the animals took part in competitions; they were not specially used in races and were mostly used for the training of junior riders and sportsmen of different levels. Blood was taken in conditions of relative rest after ordinary training and after emotional stress during the entertainment performances when a large number of people were present and loud music was played. In the blood serum the following biochemical indicators were defined: whole protein, urea, creatinine, uric acid, total bilirubin and its fractions, glucose, cholestererol, triacylglycerol, calcium, ferrum, lactate, pyruvate, activity of the AlAT, SGOT, GGTP, LDH, an alkaline phosphatase – which makes it possible to determine reasonably accurately the adaptation potential of a horse under various types of loading. We established that during training and psychoemotional loading of racing horses of the training group of the Ukrainian riding breed, multidirectional changes in the level of biochemical indicators of blood serum occurred, which is evidence of stress in the metabolic processes in the animals’ organisms. Concentration of a biomarker of an oxidative stress, uric acid, increased after physical loading by 8.6%, and after emotional loading by 55.1%, which demonstrates that emotional stress had the more negative effect, indicating insufficient adaptation by the horses before demonstration performances. After physical loading, reaction of transamination in the horses’ liver cells intensified, and after emotional loading its intensity

  18. Transgenic zebrafish eggs containing bactericidal peptide is a novel food supplement enhancing resistance to pathogenic infection of fish.

    Science.gov (United States)

    Lin, Cheng-Yung; Yang, Ping-Hsi; Kao, Chia-Ling; Huang, Han-I; Tsai, Huai-Jen

    2010-03-01

    Zebrafish (Danio rerio) was used as a bioreactor to produce bovine lactoferricin (LFB), which has wide-ranging antimicrobial activity. We constructed an expression plasmid in which LFB was fused with green fluorescent protein (GFP) and driven by zebrafish beta-actin promoter. After microinjection, six transgenic founders were screened on the basis of GFP appearance. Among them, a stable ZBL-5 line was selected by the ubiquitous and strong expression of GFP. Using PCR and Western blot analysis, we confirmed that the recombinant LFB-GFP protein was produced by the F2 progeny derived from the ZBL-5 line. The bactericidal agar plate assay proved that the functional domain of LFB was released from the LFB-GFP fusion protein, resulting in strong bactericidal activity against Escherichia coli, Edwardsiella tarda and Aeromonas hydrophila. Furthermore, adult zebrafish were given one feeding of fifty 72-hpf transgenic embryos. The treated fish were then immersed in freshwater containing 1 x 10(5) CFU ml(-1)E. tarda for 7 days. The survival rate of the treated zebrafish was significantly higher than that of fish fed with fifty wild-type embryos (75 +/- 12.5% versus 4 +/- 7.2%). This line of evidence suggested that pathogen resistance can be enhanced by using transgenic embryos containing LFB-GFP as a food supplement for fish, while, at the same time, reducing the demand of chemical antibiotics. Copyright 2009 Elsevier Ltd. All rights reserved.

  19. Two approaches to form antibacterial surface: Doping with bactericidal element and drug loading

    International Nuclear Information System (INIS)

    Sukhorukova, I.V.; Sheveyko, A.N.; Kiryukhantsev-Korneev, Ph.V.; Anisimova, N.Y.; Gloushankova, N.A.; Zhitnyak, I.Y.; Benesova, J.; Amler, E.; Shtansky, D.V.

    2015-01-01

    Graphical abstract: - Highlights: • Bioactive materials with rate-controlled release of antibacterial agent. • Ag + ion release from TiCaPCON-Ag films depended on Ag content. • TiCaPCON-coated Ti network structure with blind pores loaded with co-amoxiclav. • Strong bactericidal effect of drug-loaded samples. • Antibacterial yet biocompatible and bioactive surfaces. - Abstract: Two approaches (surface doping with bactericidal element and loading of antibiotic into specially formed surface microcontainers) to the fabrication of antibacterial yet biocompatible and bioactive surfaces are described. A network structure with square-shaped blind pores of 2.6 ± 0.6 × 10 −3 mm 3 for drug loading was obtained by selective laser sintering (SLS). The SLS-fabricated samples were loaded with 0.03, 0.3, 2.4, and 4 mg/cm 2 of co-amoxiclav (amoxicillin and clavulanic acid). Ag-doped TiCaPCON films with 0.4, 1.2, and 4.0 at.% of Ag were obtained by co-sputtering of composite TiC 0.5 -Ca 3 (PO 4 ) 2 and metallic Ag targets. The surface structure of SLS-prepared samples and cross-sectional morphology of TiCaPCON-Ag films were studied by scanning electron microscopy. The through-thickness of Ag distribution in the TiCaPCON-Ag films was obtained by glow discharge optical emission spectroscopy. The kinetics of Ag ion release in normal saline solution was studied using inductively coupled plasma mass spectrometry. Bacterial activity of the samples was evaluated against S. epidermidis, S. aureus, and K. pneum. ozaenae using the agar diffusion test and photometric method by controlling the variation of optical density of the bacterial suspension over time. Cytocompatibility of the Ag-doped TiCaPCON films was observed in vitro using chondrocytic and MC3T3-E1 osteoblastic cells. The viability and proliferation of chondrocytic cells were determined using the MTS assay and PicoGreen assay tests, respectively. The alkaline phosphatase (ALP) activity of the SLS-fabricated samples

  20. Two approaches to form antibacterial surface: Doping with bactericidal element and drug loading

    Energy Technology Data Exchange (ETDEWEB)

    Sukhorukova, I.V.; Sheveyko, A.N.; Kiryukhantsev-Korneev, Ph.V. [National University of Science and Technology “MISIS”, Leninsky pr. 4, Moscow 119049 (Russian Federation); Anisimova, N.Y.; Gloushankova, N.A.; Zhitnyak, I.Y. [N.N Blokhin Russian Cancer Research Center of RAMS, Kashirskoe shosse 24, Moscow 115478 (Russian Federation); Benesova, J. [Institute of Experimental Medicine of the ASCR, Vídenska 1083, Prague 14220 (Czech Republic); Institute of Biophysics, 2nd Faculty of Medicine, Charles University in Prague, V Uvalu 84, Prague 15006 (Czech Republic); Amler, E. [Institute of Experimental Medicine of the ASCR, Vídenska 1083, Prague 14220 (Czech Republic); Faculty of Biomedical Engineering, Czech Technical University in Prague (Czech Republic); Shtansky, D.V., E-mail: shtansky@shs.misis.ru [National University of Science and Technology “MISIS”, Leninsky pr. 4, Moscow 119049 (Russian Federation)

    2015-03-01

    Graphical abstract: - Highlights: • Bioactive materials with rate-controlled release of antibacterial agent. • Ag{sup +} ion release from TiCaPCON-Ag films depended on Ag content. • TiCaPCON-coated Ti network structure with blind pores loaded with co-amoxiclav. • Strong bactericidal effect of drug-loaded samples. • Antibacterial yet biocompatible and bioactive surfaces. - Abstract: Two approaches (surface doping with bactericidal element and loading of antibiotic into specially formed surface microcontainers) to the fabrication of antibacterial yet biocompatible and bioactive surfaces are described. A network structure with square-shaped blind pores of 2.6 ± 0.6 × 10{sup −3} mm{sup 3} for drug loading was obtained by selective laser sintering (SLS). The SLS-fabricated samples were loaded with 0.03, 0.3, 2.4, and 4 mg/cm{sup 2} of co-amoxiclav (amoxicillin and clavulanic acid). Ag-doped TiCaPCON films with 0.4, 1.2, and 4.0 at.% of Ag were obtained by co-sputtering of composite TiC{sub 0.5}-Ca{sub 3}(PO{sub 4}){sub 2} and metallic Ag targets. The surface structure of SLS-prepared samples and cross-sectional morphology of TiCaPCON-Ag films were studied by scanning electron microscopy. The through-thickness of Ag distribution in the TiCaPCON-Ag films was obtained by glow discharge optical emission spectroscopy. The kinetics of Ag ion release in normal saline solution was studied using inductively coupled plasma mass spectrometry. Bacterial activity of the samples was evaluated against S. epidermidis, S. aureus, and K. pneum. ozaenae using the agar diffusion test and photometric method by controlling the variation of optical density of the bacterial suspension over time. Cytocompatibility of the Ag-doped TiCaPCON films was observed in vitro using chondrocytic and MC3T3-E1 osteoblastic cells. The viability and proliferation of chondrocytic cells were determined using the MTS assay and PicoGreen assay tests, respectively. The alkaline phosphatase (ALP

  1. Increased activation of blood coagulation in pregnant women with the Factor V Leiden mutation.

    Science.gov (United States)

    Kjellberg, Ulla; van Rooijen, Marianne; Bremme, Katarina; Hellgren, Margareta

    2014-10-01

    The risk of venous thromboembolism is enhanced in pregnant carriers of the Factor V Leiden mutation. The primary aim of the study was to compare prothrombin fragments 1+2, soluble fibrin and D-dimer levels in pregnant Factor V Leiden mutation carriers with those in non-carriers. Secondary aims were to evaluate whether these biomarkers could predict placenta-mediated complications or venous thromboembolism, and to study blood coagulation after caesarean section with thromboprophylaxis and after vaginal delivery without thromboprophylaxis. Prothrombin fragments 1+2, soluble fibrin and D-dimer levels were studied longitudinally in 476 carriers with singleton pregnancies from gestational weeks 23-25 until 8-10 weeks postpartum. Prothrombin fragments 1+2 and D-dimer levels gradually increased during pregnancy. D-dimer levels were higher in carriers, both during pregnancy and puerperium, compared to non-carriers. D-dimer levels above 0.5mg/l were found in about 30% and 20% of the heterozygous carriers at 4-5 and 8-10 weeks postpartum, respectively. Soluble fibrin levels were mainly unchanged during pregnancy, with no difference between carriers and non-carriers. Biomarker levels were similar in carriers with uncomplicated and complicated pregnancies. Higher D-dimer levels indicate increased blood coagulation and fibrinolysis activity in carriers. The high proportion of carriers with D-dimer levels exceeding 0.5mg/l postpartum must be considered when assessing the probability of venous thromboembolism. Large overlaps in biomarker levels in normal and complicated pregnancies suggest that these biomarkers cannot be used as predictors. Thromboprophylaxis following caesarean section may prevent increased activation of blood coagulation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Blood Stem Cell Activity Is Arrested by Th1-Mediated Injury Preventing Engraftment following Nonmyeloablative Conditioning

    Science.gov (United States)

    Florek, Mareike; Kohrt, Holbrook E. K.; Küpper, Natascha J.; Filatenkov, Alexander; Linderman, Jessica A.; Hadeiba, Husein; Negrin, Robert S.

    2016-01-01

    T cells are widely used to promote engraftment of hematopoietic stem cells (HSCs) during an allogeneic hematopoietic cell transplantation. Their role in overcoming barriers to HSC engraftment is thought to be particularly critical when patients receive reduced doses of preparative chemotherapy and/or radiation compared with standard transplantations. In this study, we sought to delineate the effects CD4+ cells on engraftment and blood formation in a model that simulates clinical hematopoietic cell transplantation by transplanting MHC-matched, minor histocompatibility–mismatched grafts composed of purified HSCs, HSCs plus bulk T cells, or HSCs plus T cell subsets into mice conditioned with low-dose irradiation. Grafts containing conventional CD4+ T cells caused marrow inflammation and inhibited HSC engraftment and blood formation. Posttransplantation, the marrows of HSCs plus CD4+ cell recipients contained IL-12–secreting CD11c+ cells and IFN-γ–expressing donor Th1 cells. In this setting, host HSCs arrested at the short-term stem cell stage and remained in the marrow in a quiescent cell cycling state (G0). As a consequence, donor HSCs failed to engraft and hematopoiesis was suppressed. Our data show that Th1 cells included in a hematopoietic allograft can negatively impact HSC activity, blood reconstitution, and engraftment of donor HSCs. This potential negative effect of donor T cells is not considered in clinical transplantation in which bulk T cells are transplanted. Our findings shed new light on the effects of CD4+ T cells on HSC biology and are applicable to other pathogenic states in which immune activation in the bone marrow occurs such as aplastic anemia and certain infectious conditions. PMID:27815446

  3. Does self-reported physical activity associate with high blood pressure in adolescents when adiposity is adjusted for?

    Science.gov (United States)

    Barros, Mauro V G; Ritti-Dias, Raphael Mendes; Honda Barros, Simone Storino; Mota, Jorge; Andersen, Lars Bo

    2013-01-01

    Studies show that both low physical activity (PA) and adiposity are associated with a higher risk of hypertension. However, the relationship between PA and blood pressure in adolescents is controversial and other studies have reported that no association was observed. Of particular interest is the evaluation of whether the association between PA and high blood pressure is independent of adiposity. A sample of 3764 Brazilian adolescents who attend high schools was selected using random cluster sampling. Data were collected using the Global School-based Student Health Survey, anthropometry, and blood pressure readings. The prevalence of high blood pressure was 14.6% (95% Confidence Interval (CI) 13.5-15.7), higher amongst males (20.0%; 95%CI 18.0-22.1) compared with females (10.9%; 95%CI 9.7-12.3). Sixty-six per cent of the adolescents were reported to be insufficiently active. The prevalence of high blood pressure was 12.8% (95%CI 11.0-14.7) amongst active compared with 15.4% (95%CI 14.0-16.9) amongst insufficiently active adolescents. The association between PA and high blood pressure was observed only amongst females after adjusting for waist circumference (odds ratio (OR) 1.67; 95%CI 1.21-2.31) and body mass index (OR 1.71; 95%CI 1.23-2.37). Notwithstanding levels of adiposity, higher PA levels are associated with a lower prevalence of high blood pressure amongst females, although not amongst males.

  4. Simple surface sulfonation retards plasticiser migration and impacts upon blood/material contact activation processes.

    Science.gov (United States)

    Gourlay, Terence; Shedden, Laurie; Horne, David; Stefanou, Demetrios M

    2010-01-01

    The use of Di-2-ethylhexyl phthalate (DEHP) plasticised polyvinyl chloride (DEHPPPVC) in medical devices persists despite evidence suggesting that DEHP migration can be harmful. Researchers have shown that a simple surface sulfonation process can retard the migration of DEHP, which may reduce the associated inflammatory response. The present study is designed to investigate the effects of surface sulfonation on DEHP migration and blood contact activation using in vitro and rodent models. The study was carried out in two phases: phase 1, in which the migration rate of DEHP from DEHPPPVC and sulfonated DEHP plasticised PVC (SDEHPPPVC) was measured; phase 2 of the study, in which the materials were incorporated into a rat recirculation biomaterial test model and blood samples taken to assess CD11b expression on neutrophils, IL-6 and Factor XIIa. The initial DEHP concentration washed from the surface after storage was 37.19 +/- 1.17 mg/l in the PPVC group and 5.89 +/- 0.81 mg/l in the SPPVC group (psulfonation process significantly retards the migration of DEHP and is associated with the moderation of contact activation processes.

  5. Associations among environmental supports, physical activity, and blood pressure in African-American adults in the PATH trial.

    Science.gov (United States)

    Coulon, Sandra M; Wilson, Dawn K; Egan, Brent M

    2013-06-01

    High blood pressure disproportionately affects African-American adults and is a leading cause of stroke and heart attack. Engaging in recommended levels of physical activity reduces blood pressure, and social and physical environmental supports for physical activity may increase engagement in physical activity. Based on social cognitive theory within a bioecological framework, the present study tested hypotheses that perceived peer social support for physical activity and neighborhood walkability would be positively associated with physical activity, and that physical activity would mediate their relation with blood pressure. Baseline data were collected with 434 African-American adults in underserved communities (low income, high crime) participating in the Positive Action for Today's Health (PATH) trial. Perceived peer social support for physical activity and neighborhood walkability were measured with validated surveys. Physical activity was assessed with 7-day accelerometry (moderate-to-vigorous physical activity, min/day) and with a 4-week recall of walking. Three blood pressure assessments were taken by trained staff using standard protocols, with values from the second and third assessments averaged. The sample was predominantly female (63%), overweight (mean body mass index = 30.9, SD = 8.4), and had slightly elevated blood pressures with a mean systolic blood pressure of 132.4 (SD = 17.9) and a mean diastolic blood pressure of 81.4 (SD = 11.0). Results demonstrated that peer social support for physical activity (B = 2.43, p = .02) and neighborhood walkability (B = 2.40, p = .046) were significantly related to average daily moderate-to-vigorous physical activity. Neighborhood walkability was also significantly associated with self-reported average daily walking (B = 8.86, p = .02). Physical activity did not mediate their relation with blood pressure and no significant direct effects of these variables on blood pressure were found. The positive influence of

  6. Effect of Fatty Acid Conjugation on Antimicrobial Peptide Activity

    National Research Council Canada - National Science Library

    Chu-Kung, Alexander F; Bozzelli, Kristen N; Nguyen, Rose; Tirrell, Matthew V

    2004-01-01

    ... or the conjugate of the nonamphipathic peptide, KAK. The induction of helicity corresponds to a significant improvement in antimicrobial activity as measured by a minimum bactericidal concentration test...

  7. Bactericidal Immunity to Salmonella in Africans and Mechanisms Causing Its Failure in HIV Infection.

    Directory of Open Access Journals (Sweden)

    Yun Shan Goh

    2016-04-01

    Full Text Available Nontyphoidal strains of Salmonella are a leading cause of death among HIV-infected Africans. Antibody-induced complement-mediated killing protects healthy Africans against Salmonella, but increased levels of anti-lipopolysaccharide (LPS antibodies in some HIV-infected African adults block this killing. The objective was to understand how these high levels of anti-LPS antibodies interfere with the killing of Salmonella.Sera and affinity-purified antibodies from African HIV-infected adults that failed to kill invasive S. Typhimurium D23580 were compared to sera from HIV-uninfected and HIV-infected subjects with bactericidal activity. The failure of sera from certain HIV-infected subjects to kill Salmonella was found to be due to an inherent inhibitory effect of anti-LPS antibodies. This inhibition was concentration-dependent and strongly associated with IgA and IgG2 anti-LPS antibodies (p<0.0001 for both. IgG anti-LPS antibodies, from sera of HIV-infected individuals that inhibit killing at high concentration, induced killing when diluted. Conversely, IgG, from sera of HIV-uninfected adults that induce killing, inhibited killing when concentrated. IgM anti-LPS antibodies from all subjects also induced Salmonella killing. Finally, the inhibitory effect of high concentrations of anti-LPS antibodies is seen with IgM as well as IgG and IgA. No correlation was found between affinity or avidity, or complement deposition or consumption, and inhibition of killing.IgG and IgM classes of anti-S. Typhimurium LPS antibodies from HIV-infected and HIV-uninfected individuals are bactericidal, while at very high concentrations, anti-LPS antibodies of all classes inhibit in vitro killing of Salmonella. This could be due to a variety of mechanisms relating to the poor ability of IgA and IgG2 to activate complement, and deposition of complement at sites where it cannot insert in the bacterial membrane. Vaccine trials are required to understand the significance of

  8. Mechanistic Study of Silver Nanoparticle's Synthesis by Dragon's Blood Resin Ethanol Extract and Antiradiation Activity.

    Science.gov (United States)

    Hasan, Murtaza; Iqbal, Javed; Awan, Umer; Saeed, Yasmeen; Ranran, Yuan; Liang, Yanli; Dai, Rongji; Deng, Yulin

    2015-02-01

    Biological synthesis of nanoparticles is best way to avoid exposure of hazardous materials as compared to chemical manufacturing process which is a severe threat not only to biodiversity but also to environment. In present study, we reported a novel method of finding antiradiation compounds by bioreducing mechanism of silver nanoparticles formation using 50% ethanol extract of Dragons blood, a famous Chinese herbal plant. Color change during silver nanoparticles synthesis was observed and it was confirmed by ultra violet (UV) visible spectroscopy at wave length at 430 nm after 30 min of reaction at 60 °C. Well dispersed round shaped silver nanoparticles with approximate size (4 nm to 50 nm) were measured by TEM and particle size analyser. Capping of biomolecules on Ag nanoparticles was characterized by FTIR spectra. HPLC analysis was carried out to find active compounds in the extract. Furthermore, antiradiation activity of this extract was tested by MTT assay in vitro after incubating the SH-SY5Y cells for 24 h at 37 °C. The results indicate that presence of active compounds in plant extract not only involves in bioreduction process but also shows response against radiation. The dual role of plant extract as green synthesis of nanoparticles and exhibit activity against radiation which gives a new way of fishing out active compounds from complex herbal plants.

  9. Effect of Active and Passive Recovery on Athletes' White Blood Cell Count

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    P Piraki

    2012-05-01

    Full Text Available

    Background and Objectives

    Exercise affects the immune system. The aim of this study is comparison of the effect of active and passive recovery (AR and RR, respectively on differential white blood cell (WBC count after an exhaustive exercise session in athlete males.

    Methods

    Twenty male athletes who signed an informed consent form were randomly divided in to two equal groups. Their blood samples were drawn at rest, immediately after an exhaustive exercise session, immediately after 15 minutes active and passive recovery from an exhaustive exercise session. A WBC’s (lymphocytes, monocytes, neutrophils, basohils, and eosinophils count was done on all of these samples.

    This exercise protocol was based on the Bruce Protocol Treadmill Stress Test until feeling excessive fatigue followed by AR (first group, and RR (second group.Wilcoxon signed-rank and Mann-Whitney test were used for descriptive and statistical analysis on collected raw data. Statistical significance in this analysis was set at P ≤ 0.05.

    Results

    A session of exhaustive exercise increased the number of WBCs (except for eosinophils with a statistical significant differences of (P<0.05. A Comparison of the changes before and after workout, showed no statistical significant difference. Also, a 15 minute AR and RR, didn't alter WBCs count (all P>0.05.

    Conclusion

    The results show a session of exhaustive exercise increases the blood leukocytes, except for eosinophils. Also, taking 15 minutes recovery (AR or RR has no effect on athlete's WBC count. It means the type of recovery has no special and different effect on athlete's WBC count. In fact, if there are any changes in WBC count during or after exhaustive exercise, they are not due to the type of 15 minutes recovery. Furthermore, under the conditions of this study after completing the AR and RR, number of the blood

  10. Bactericidal Immunity to Salmonella in Africans and Mechanisms Causing Its Failure in HIV Infection

    Science.gov (United States)

    Goh, Yun Shan; Necchi, Francesca; O’Shaughnessy, Colette M.; Micoli, Francesca; Gavini, Massimiliano; Young, Stephen P.; Msefula, Chisomo L.; Gondwe, Esther N.; Mandala, Wilson L.; Gordon, Melita A.; Saul, Allan J.; MacLennan, Calman A.

    2016-01-01

    Background Nontyphoidal strains of Salmonella are a leading cause of death among HIV-infected Africans. Antibody-induced complement-mediated killing protects healthy Africans against Salmonella, but increased levels of anti-lipopolysaccharide (LPS) antibodies in some HIV-infected African adults block this killing. The objective was to understand how these high levels of anti-LPS antibodies interfere with the killing of Salmonella. Methodology/Principal Findings Sera and affinity-purified antibodies from African HIV-infected adults that failed to kill invasive S. Typhimurium D23580 were compared to sera from HIV-uninfected and HIV-infected subjects with bactericidal activity. The failure of sera from certain HIV-infected subjects to kill Salmonella was found to be due to an inherent inhibitory effect of anti-LPS antibodies. This inhibition was concentration-dependent and strongly associated with IgA and IgG2 anti-LPS antibodies (pbactericidal, while at very high concentrations, anti-LPS antibodies of all classes inhibit in vitro killing of Salmonella. This could be due to a variety of mechanisms relating to the poor ability of IgA and IgG2 to activate complement, and deposition of complement at sites where it cannot insert in the bacterial membrane. Vaccine trials are required to understand the significance of lack of in vitro killing by anti-LPS antibodies from a minority of HIV-infected individuals with impaired immune homeostasis. PMID:27057743

  11. Antimicrobial strategies centered around reactive oxygen species - bactericidal antibiotics, photodynamic therapy and beyond

    Science.gov (United States)

    Vatansever, Fatma; de Melo, Wanessa C.M.A.; Avci, Pinar; Vecchio, Daniela; Sadasivam, Magesh; Gupta, Asheesh; Chandran, Rakkiyappan; Karimi, Mahdi; Parizotto, Nivaldo A; Yin, Rui; Tegos, George P; Hamblin, Michael R

    2013-01-01

    Reactive oxygen species (ROS) can attack a diverse range of targets to exert antimicrobial activity, which accounts for their versatility in mediating host defense against a broad range of pathogens. Most ROS are formed by the partial reduction of molecular oxygen. Four major ROS are recognized comprising: superoxide (O2•−), hydrogen peroxide (H2O2), hydroxyl radical (•OH), and singlet oxygen (1O2), but they display very different kinetics and levels of activity. The effects of O2•− and H2O2 are less acute than those of •OH and 1O2, since the former are much less reactive and can be detoxified by endogenous antioxidants (both enzymatic and non-enzymatic) that are induced by oxidative stress. In contrast, no enzyme can detoxify •OH or 1O2, making them extremely toxic and acutely lethal. The present review will highlight the various methods of ROS formation and their mechanism of action. Antioxidant defenses against ROS in microbial cells and the use of ROS by antimicrobial host defense systems are covered. Antimicrobial approaches primarily utilizing ROS comprise both bactericidal antibiotics, and non-pharmacological methods such as photodynamic therapy, titanium dioxide photocatalysis, cold plasma and medicinal honey. A brief final section covers, reactive nitrogen species, and related therapeutics, such as acidified nitrite and nitric oxide releasing nanoparticles. PMID:23802986

  12. Bactericidal Effect of Pterostilbene Alone and in Combination with Gentamicin against Human Pathogenic Bacteria

    Directory of Open Access Journals (Sweden)

    Wee Xian Lee

    2017-03-01

    Full Text Available The antibacterial activity of pterostilbene in combination with gentamicin against six strains of Gram-positive and Gram-negative bacteria were investigated. The minimum inhibitory concentration and minimum bactericidal concentration of pterostilbene were determined using microdilution technique whereas the synergistic antibacterial activities of pterostilbene in combination with gentamicin were assessed using checkerboard assay and time-kill kinetic study. Results of the present study showed that the combination effects of pterostilbene with gentamicin were synergistic (FIC index < 0.5 against three susceptible bacteria strains: Staphylococcus aureus ATCC 25923, Escherichia coli O157 and Pseudomonas aeruginosa 15442. However, the time-kill study showed that the interaction was indifference which did not significantly differ from the gentamicin treatment. Furthermore, time-kill study showed that the growth of the tested bacteria was completely attenuated with 2 to 8 h treatment with 0.5 × MIC of pterostilbene and gentamicin. The identified combinations could be of effective therapeutic value against bacterial infections. These findings have potential implications in delaying the development of bacterial resistance as the antibacterial effect was achieved with the lower concentrations of antibacterial agents.

  13. Agglutinating and bactericidal properties of fractions of rabbit anti-Vibrio cholerae serum.

    Science.gov (United States)

    Pike, R M; Chandler, C H

    1969-06-01

    The major portion of the agglutinating and bactericidal activity of the sera of rabbits immunized with live Vibrio cholerae or with cholera vaccine was found in the gammaM fractions during the early stages of immunization. After 5 weeks or more, gammaG fractions accounted for more than half of the agglutinating activity. When late antibody was measured as the amount of protein precipitated by somatic antigens, nearly 3 times as much gammaG as gammaM was required for agglutination, and about 30 times as much gammaG as gammaM was required to kill 50% of a standard inoculum in the presence of complement. The ratio of vibriocidal to agglutinin titer of gammaG fractions at different stages of immunization was more variable than that of gammaM fractions. More complement was required for a vibriocidal effect by gammaG than by gammaM. Increasing the amount of complement decreased the amount of both gammaG and gammaM required to kill, but smaller amounts of gammaM required disproportionately larger amounts of complement. Less time was required by gammaM than by gammaG to kill 50% of the inoculum. Removal of the group-reactive antibody from anti-Ogawa serum and serum fractions by absorption with Inaba reduced the vibriocidal titer by more than one-half.

  14. Green tea and epigallocatechin-3-gallate are bactericidal against Bacillus anthracis.

    Science.gov (United States)

    Falcinelli, Shane D; Shi, Maggie C; Friedlander, Arthur M; Chua, Jennifer

    2017-07-03

    Bacillus anthracis, the etiological agent of anthrax, is listed as a category A biothreat agent by the United States Centers for Disease Control and Prevention. The virulence of the organism is due to expression of two exotoxins and capsule, which interfere with host cellular signaling, alter host water homeostasis and inhibit phagocytosis of the pathogen, respectively. Concerns regarding the past and possible future use of B. anthracis as a bioterrorism agent have resulted in an impetus to develop more effective protective measures and therapeutics. In this study, green tea was found to inhibit the in vitro growth of B. anthracis. Epigallocatechin-3-gallate (EGCG), a compound found abundantly in green tea, was shown to be responsible for this activity. EGCG was bactericidal against both the attenuated B. anthracis ANR and the virulent encapsulated B. anthracis Ames strain. This study highlights the antimicrobial activity of green tea and EGCG against anthrax and suggests the need for further investigation of EGCG as a therapeutic candidate against B. anthracis. Published by Oxford University Press on behalf of FEMS 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  15. Bactericidal mechanism of glutaraldehyde-didecyldimethylammonium bromide as a disinfectant against Escherichia coli.

    Science.gov (United States)

    Lin, W; Guan, X; Cao, J; Niu, B; Chen, Q

    2017-03-01

    This study focuses on the bactericidal mechanism of the new combination of disinfectant glutaraldehyde-didecyldimethylammonium bromide (GA-DDAB) against Escherichia coli. Escherichia coli were exposed to GA-DDAB, and assays for cell morphology, K + and Ca 2+ leakage, H + -ATPase activity and DNA degradation were performed. GA-DDAB damaged the cell wall and disrupted cell-membrane integrity. Leakage of K + and Ca 2+ increased, resulting in significantly lower intracellular concentrations within 60 min of treatment. In addition, H + -ATPase was inactivated and DNA was degraded. Leakage of intracellular components indicated that GA-DDAB damaged the cell membrane of E. coli. This may have caused the observed disruption in equilibria of metal ions, inactivation of H + -ATPase, and DNA damage. Using a low concentration of GA and DDAB, a new combination disinfectant was developed. GA-DDAB displayed higher antimicrobial activity than treatment with GA or DDAB alone. Therefore, GA-DDAB may be a more cost-effective and efficient antimicrobial agent than others in use today. Furthermore, this study provided a paradigm for developing high-efficiency disinfectant to help address the growing problem of bacterial resistance. © 2016 The Society for Applied Microbiology.

  16. [EFFECT OF VOLUNTARY BREATH-HOLDING AND COGNITIVE LOADS ON REGIONAL CEREBRAL BLOOD FLOW AND BIOELECTRIC ACTIVITY OF THE BRAIN].

    Science.gov (United States)

    Moreva, T I; Pasekova, O B; Kriushev, E S; Dobrokvashina, E I; Moreva, O V; Builov, S P; Smirnov, O A; Bragin, L Kh; Voronkov, Iu I

    2015-01-01

    Cerebral blood flow and bioelectric activity were studied in 10 normal volunteers in order to assess cerebrovascular reactivity during different types of functional testing. The transcranial Doppler was used to measure linear blood velocity (LBV) in the middle cerebral artery (MCA) during maximal voluntary breath-holding (apnea), controlled verbal association test and tactile memory test. Simultaneous electroencephalography (EEG) registered the bioelectric activity of the brain cortex. Both investigations were performed continuously in the course of each test. Breath-holding induced a smooth symmetric increase of CMA blood velocity; LBV rose to maximum values in the majority of the volunteered subjects. Two subjects with small focal changes in the brain's white matter displayed an asymmetric blood flow reaction to apnea. Gain in LBV was materially less during the cognitive tests; the verbal test decreased LBV in one half of the subjects and increased LBV in the other. The tactile memory test increased LBV which was particularly high in the left CMA of all subjects. LBV dynamics during the cognitive tests was essentially different from what was observed in apnea. Blood flow variations in the course of equally the verbal and tactile tests had a regular undulatory character. Concurrent LBV and EEG monitoring made it possible to compare and contrast dynamics of the cerebral blood velocity and bioelectric activity directly during testing and thus to reveal peculiar reactions of the cerebral blood flow to cognitive and physiological testing.

  17. HCG-Activated Human Peripheral Blood Mononuclear Cells (PBMC) Promote Trophoblast Cell Invasion

    Science.gov (United States)

    Wang, Yaqin; Guo, Yue; Zhou, Danni; Xu, Mei; Ding, Jinli; Yang, Jing

    2015-01-01

    Successful embryo implantation and placentation depend on appropriate trophoblast invasion into the maternal endometrial stroma. Human chorionic gonadotropin (hCG) is one of the earliest embryo-derived secreted signals in the peripheral blood mononuclear cells (PBMC) that abundantly expresses hCG receptors. The aims of this study were to estimate the effect of human embryo–secreted hCG on PBMC function and investigate the role and underlying mechanisms of activated PBMC in trophoblast invasion. Blood samples were collected from women undergoing benign gynecological surgery during the mid-secretory phase. PBMC were isolated and stimulated with or without hCG for 0 or 24 h. Interleukin-1β (IL-1β) and leukemia inhibitory factor (LIF) expressions in PBMC were detected by enzyme-linked immunosorbent assay and real-time polymerase chain reaction (PCR). The JAR cell line served as a model for trophoblast cells and was divided into four groups: control, hCG only, PBMC only, and PBMC with hCG. JAR cell invasive and proliferative abilities were detected by trans-well and CCK8 assays and matrix metalloproteinase (MMP)-2 (MMP-2), MMP-9, vascular endothelial growth factor (VEGF), tissue inhibitor of metalloproteinase (TIMP)-1, and TIMP-2 expressions in JAR cells were detected by western blotting and real-time PCR analysis. We found that hCG can remarkably promote IL-1β and LIF promotion in PBMC after 24-h culture. PBMC activated by hCG significantly increased the number of invasive JAR cells in an invasion assay without affecting proliferation, and hCG-activated PBMC significantly increased MMP-2, MMP-9, and VEGF and decreased TIMP-1 and TIMP-2 expressions in JAR cells in a dose-dependent manner. This study demonstrated that hCG stimulates cytokine secretion in human PBMC and could stimulate trophoblast invasion. PMID:26087261

  18. Evidence of Active Pro-Fibrotic Response in Blood of Patients with Cirrhosis.

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    Gloria Sanchez-Antolín

    Full Text Available The role of systemic immunity in the pathogenesis of cirrhosis is not fully understood. Analysis of transcriptomic profiles in blood is an easy approach to obtain a wide picture of immune response at the systemic level. We studied gene expression profiles in blood from thirty cirrhotic patients and compared them against those of eight healthy volunteers. Most of our patients were male [n = 21, 70%] in their middle ages [57.4 ± 6.8 yr]. Alcohol abuse was the most frequent cause of cirrhosis (n = 22, 73%. Eleven patients had hepatocellular carcinoma (36.7%. Eight patients suffered from hepatitis C virus infection (26.7%. We found a signature constituted by 3402 genes which were differentially expressed in patients compared to controls (2802 over-expressed and 600 under-expressed. Evaluation of this signature evidenced the existence of an active pro-fibrotic transcriptomic program in the cirrhotic patients, involving the [extra-cellular matrix (ECM-receptor interaction] & [TGF-beta signaling] pathways along with the [Cell adhesion molecules] pathway. This program coexists with alterations in pathways participating in [Glycine, serine and threonine metabolism], [Phenylalanine metabolism], [Tyrosine metabolism], [ABC transporters], [Purine metabolism], [Arachidonic acid metabolism]. In consequence, our results evidence the co-existence in blood of a genomic program mediating pro-fibrotic mechanisms and metabolic alterations in advanced cirrhosis. Monitoring expression levels of the genes involved in these programs could be of interest for predicting / monitoring cirrhosis evolution. These genes could constitute therapeutic targets in this disease.

  19. Novel aspects of blood coagulation factor XIII. I. Structure, distribution, activation, and function

    Energy Technology Data Exchange (ETDEWEB)

    Muszbek, L.; Adany, R. [Univ. Medical School of Debrecen (Hungary); Mikkola, H. [Univ. of Helsinki (Finland)

    1996-10-01

    Blood coagulation factor XIII (FXIII) is a protransglutaminase that becomes activated by the concerted action of thrombin and Ca{sup 2+} in the final stage of the clotting cascade. In addition to plasma, FXIII also occurs in platelets, monocytes, and monocyte-derived macrophages. While the plasma factor is a heterotetramer consisting of paired A and B subunits (A{sub 2}B{sub 2}), its cellular counterpart lacks the B subunits and is a homodimer of potentially active A subunits (A{sub 2}). The gene coding for the A and B subunits has been localized to chromosomes 6p24-25 and 1q31-32.1, respectively. The genomic as well as the primary protein structure of both subunits has been established. Plasma FXIII circulates in association with its substrate precursor, fibrinogen. Fibrin(ogen) has an important regulatory role in the activation of plasma FXIII, for instance the proteolytic removal of activation peptide by thrombin, the dissociation of subunits A and B, and the exposure of the originally buried active site on the free A subunits. The end result of this process is the formation of an active transglutaminase, which crosslinks peptide chains through {epsilon}({gamma}-glutamyl)lysyl isopeptide bonds. The protein substrates of activated FXIII include components of the clotting-fibrinolytic system, adhesive and contractile proteins. The main physiological function of plasma FXIII is to cross-link fibrin and protect it from the fibrinolytic enzyme plasmin. The latter effect is achieved mainly by covalently linking {alpha}{sub 2} antiplasmin, the most potent physiological inhibitor of plasmin, to fibrin. Plasma FXIII seems to be involved in wound healing and tissue repair, and it is essential to maintaining pregnancy. Cellular FXIII, if exposed to the surface of the cells, might support or perhaps take over the hemostatic functions of plasma FXIII; however, its intracellular role has remained mostly unexplored. 328 refs., 4 figs.

  20. Activity behaviors in schoolchildren and subsequent 5-yr change in blood pressure.

    Science.gov (United States)

    Gopinath, Bamini; Hardy, Louise L; Kifley, Annette; Baur, Louise A; Mitchell, Paul

    2014-04-01

    This study aimed to establish whether time spent in sport-related physical activities and sedentary behaviors (e.g., TV viewing, videogame usage, and homework) was prospectively associated with change in blood pressure (BP) for 5 yr. Eight hundred and twenty-one students age 6 yr at baseline (397 girls and 424 boys) were examined from 2003-2004 to 2009-2011. Children completed detailed activity questionnaires. BP was measured using a standardized protocol. After adjusting for age, ethnicity, parental education, parental history of hypertension, baseline height, BP, body mass index (BMI), baseline time spent in corresponding activity behavior, and change in BMI, each hour per day spent in total screen time was associated with a 0.69 and 0.59 mm Hg increase in diastolic BP (P = 0.01) and mean arterial BP (P = 0.01), respectively. In boys, each hour per day spent in TV viewing was associated with a concurrent 1.42-mm Hg increase in diastolic BP (P = 0.04) during the 5 yr. Children engaging in low sport-related physical activities at baseline but who engaged in high levels of physical activity (≥ 60 min · d(-1)) at follow-up (n = 154) compared with those engaging in low sport-related physical activities at both examinations (n = 305) demonstrated significantly lower mean arterial BP, 7.26 versus 9.61 mm Hg (P = 0.04). Time spent in physical activity and screen time could influence BP measures during childhood.

  1. Photocatalytic Bactericidal Efficiency of Ag Doped TiO2/Fe3O4 on Fish Pathogens under Visible Light

    Directory of Open Access Journals (Sweden)

    Ekkachai Kanchanatip

    2014-01-01

    Full Text Available This research evaluates photocatalytic bactericidal efficiencies of Ag-TiO2/Fe3O4 in visible light using target pollutants that include Aeromonas hydrophila, Edwardsiella tarda, and Photobacterium damselae subsp. piscicida. The investigation started with Ag-T