Microbial growth and importance of flushing inside closed-type infusion devices during administration of lipid emulsion in vitro setting

Triglyceride-rich lipoproteins bind and inactive bacterial endotoxin in vitro and prevent death when given before a lethal dose of endotoxin in animals. However, lipoproteins have not yet been demonstrated to improve survival in polymicrobial gram-negative sepsis. We therefore tested the ability of triglyceride-rich lipoproteins to prevent death after cecal ligation and puncture (CLP) in rats. Animals were given bolus infusions of either chylomicrons (1 g triglyceride/kg per 4 h) or an equal volume of saline for 28 h after CLP. Chylomicron infusions significantly improved survival (measured at 96 h) compared with saline controls (80 vs 27%, P < or = 0.03). Chylomicron infusions also reduced serum levels of endotoxin, measured 90 min (26 +/- 3 vs 136 +/- 51 pg/ml, mean +/- SEM, P < or = 0.03) and 6 h (121 +/- 54 vs 1,026 +/- 459 pg/ml, P < or = 0.05) after CLP. The reduction in serum endotoxin correlated with a reduction in serum tumor necrosis factor, measured 6 h after CLP (0 +/- 0 vs 58 +/- 24 pg/ml, P < or = 0.03), suggesting that chylomicrons improve survival in this model by limiting macrophage exposure to endotoxin and thereby reducing secretion of inflammatory cytokines. Infusions of a synthetic triglyceride-rich lipid emulsion (Intralipid; KabiVitrum, Inc., Alameda, CA) (1 g triglyceride/kg) also significantly improved survival compared with saline controls (71 vs 27%, P < or = 0.03). These data demonstrate that triglyceride-rich lipoproteins can protect animals from lethal polymicrobial gram-negative sepsis.

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IN VITRO DEGRADATION OF MIMOSINE BY MICROORGANISMS FROM THE ESOPHAGEAL SAC OF VOLES (Microtus arvalis)

Canadian Journal of Animal Science ◽

10.4141/cjas86-058 ◽

1986 ◽

Vol 66 (2) ◽

pp. 547-551 ◽

Cited By ~ 2

Author(s):

H. KUDO ◽

K.-J. CHENG ◽

W. MAJAK ◽

J. W. HALL ◽

T. ARAI ◽

...

Keyword(s):

Pyridine Ring ◽

Microbial Growth ◽

Early Stage ◽

Microtus Arvalis ◽

In Vitro Degradation ◽

Ruminal Microorganisms ◽

Highly Active ◽

Alfalfa Hay ◽

Degradation Rates

The microbiota in the esophageal sac of voles fed either cubed alfalfa hay or concentrate pellets were assayed to determine their capacity to anaerobically degrade mimosine in vitro. Differences (P < 0.01) were found between the two diets during the growth phase. The sac contents of voles fed concentrate pellets degraded mimosine and 3-hydroxy-4-(1H)-pyridone (DHP) rapidly, but inocula from voles fed cubed alfalfa hay only hydrolyzed mimosine to DHP. Degradation of the pyridine ring occurred at the early stage of incubation, concurrently with microbial growth. Thereafter, degradation rates appear to have been almost negligible and very similar for both diets. These results agree with previous data obtained with ruminal microorganisms, where highly active inocula were also associated with animals on concentrate diets. Key words: Detoxification, hydrolysis, esophageal sac, mimosine, 3-hydroxy-4- (1H)-pyridone, voles

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Antimicrobial activity of Arctium lappa constituents against microorganisms commonly found in endodontic infections

Brazilian Dental Journal ◽

10.1590/s0103-64402005000300004 ◽

2005 ◽

Vol 16 (3) ◽

pp. 192-196 ◽

Cited By ~ 48

Author(s):

Juliana Vianna Pereira ◽

Débora Cristina Baldoqui Bergamo ◽

José Odair Pereira ◽

Suzelei de Castro França ◽

Rosemeire Cristina Linhares Rodrigues Pietro ◽

...

Keyword(s):

Antimicrobial Activity ◽

Microbial Growth ◽

Diffusion Method ◽

Arctium Lappa ◽

Retention Factors ◽

Antimicrobial Substances ◽

Chemical Structures ◽

Microbial Inhibition ◽

Endodontic Infections

This study evaluated in vitro the antimicrobial activity of rough extracts from leaves of Arctium lappa and their phases. The following microorganisms, commonly found in the oral cavity, specifically in endodontic infections, were used: Enterococcus faecalis, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis and Candida albicans. The agar-diffusion method allowed detection of the hexanic phase as an inhibitor of microbial growth. Bioautographic assays identified antimicrobial substances in the extract. The results showed the existence, in the rough hexanic phase and in its fractions, of constituents that have retention factors (Rf) in three distinct zones, thereby suggesting the presence of active constituents with chemical structures of different polarities that exhibited specificity against the target microorganisms. It may be concluded that the Arctium lappa constituents exhibited a great microbial inhibition potential against the tested endodontic pathogens.

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Rheological examination of erythrocyte aggregation in the presence of lipid-based fine particles

Chemical Industry and Chemical Engineering Quarterly ◽

10.2298/ciceq0502049p ◽

2005 ◽

Vol 11 (2) ◽

pp. 49-54

Author(s):

Ivana Pajic-Lijakovic ◽

Branko Bugarski ◽

Milenko Plavsic

Keyword(s):

Lipid Emulsion ◽

Fine Particles ◽

Drug Carriers ◽

Erythrocyte Aggregation ◽

Rheological Parameters ◽

Aggregate Formation ◽

Structural Ordering ◽

Liposome Dispersion ◽

Structural Parts

The development of lipid-based fine particles as potential drug carriers requires a detailed investigation of the possible effects of these carriers on the rheological properties of blood. In this study, we investigated the influence of dynamic conditions on aggregate formation and stability in dispersions of lipid-based fine particles in whole blood under in vitro conditions. The rheological parameters of two concentrations of liposome dispersion and two concentrations of lipid emulsion in blood were examined. A micro-rheological model of aggregating dispersions is proposed in which the apparent viscosity is estimated as the sum of the hydrodynamic and structural parts which are correlated with system structural ordering in the flow. The dynamics of structural ordering of the aggregating system an considered by examining the evolution of the state of the system in phase space depending on the shear rate. The addition of lipid-based particles induced aggregate formation in the blood, which was more pronounced at higher concentrations of lipid-based fine particles. Furthermore, larger and more stable aggregates are formed in liposome dispersions as compared to lipid emulsions in blood.

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In vitro evaluation of microbial adhesion on the different surface roughness of acrylic resin specific for ocular prosthesis

European Journal of Dentistry ◽

10.4103/ejd.ejd_50_18 ◽

2018 ◽

Vol 12 (02) ◽

pp. 176-183 ◽

Cited By ~ 5

Author(s):

Agda Marobo Andreotti ◽

Cecília Alves De Sousa ◽

Marcelo Coelho Goiato ◽

Emily Vivianne Freitas da Silva ◽

Cristiane Duque ◽

...

Keyword(s):

Surface Roughness ◽

Staphylococcus Epidermidis ◽

Microbial Growth ◽

Acrylic Resin ◽

Microbial Adhesion ◽

Force Microscopy ◽

Atomic Force ◽

Colony Forming Units ◽

Ocular Prostheses

ABSTRACT Objective: The purpose of this study was to evaluate the influence of surface roughness in biofilm formation of four microorganisms (Staphylococcus epidermidis, Staphylococcus aureus, Enterococcus faecalis, and Candida albicans) on acrylic resin surface of ocular prostheses. Materials and Methods: Acrylic resin samples were divided into six groups according to polishing: Group 1200S (1200 grit + silica solution); Group 1200; Group 800; Group 400; Group 120 and Group unpolished. Surface roughness was measured using a profilometer and surface images obtained with atomic force microscopy. Microbial growth was evaluated after 4, 24, and 48 hours of incubation by counting colony-forming units. Statistical Analysis Used: For roughness, it was performed 1-way ANOVA and parametric Tukey test α5% (P ≤ 0.05). For CFU data found, it was applied Kruskal-Wallis and Mann-Whitney tests. Results: Group 120 and 400 presented the highest roughness values. For S. epidermidis and S. aureus, Group 1200S presented the lowest values of microbial growth. For E. faecalis at 4 hour, microbial growth was not observed. C. albicans did not adhere to the acrylic resin. Except for Group 1200S, different surface roughnesses did not statistically interfere with microbial adhesion and growth on acrylic surfaces of ocular prostheses. Conclusions: The roughness did not interfere with the microbial adhesion of the microorganisms evaluated. The use of silica decreases significantly microbial growth.

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Co-Administration of Drugs and Parenteral Nutrition: In Vitro Compatibility Studies of Loop Diuretics for Safer Clinical Practice

Pharmaceutics ◽

10.3390/pharmaceutics12111092 ◽

2020 ◽

Vol 12 (11) ◽

pp. 1092

Author(s):

Szymon Tomczak ◽

Maciej Stawny ◽

Anna Jelińska

Keyword(s):

Clinical Practice ◽

Zeta Potential ◽

Parenteral Nutrition ◽

Lipid Emulsion ◽

Droplet Diameter ◽

Loop Diuretics ◽

Compatibility Studies ◽

Emulsion Droplet ◽

Flow Rates

Parenteral nutrition (PN) admixtures are prone to interacting with drugs administered intravenously via a common catheter. This may cause a threat to a patient’s health and life. The literature that has been reported on the compatibility of loop diuretics with PN presents conflicting results. This work aimed to study the compatibility of furosemide and torsemide with PN used in clinical practice. Undiluted solutions of drugs were mixed with PN at various ratios determined by flow rates. In order to assess compatibility, visual control was followed by pH measurement, osmolality, mean emulsion droplet diameter (MDD), and zeta potential upon mixing and at 4 h of storage. No macroscopic changes that indicated lipid emulsion degradation were observed. After the addition of the drugs, the value of pH ranged from 6.37 ± 0.01 to 7.38 ± 0.01. The zeta potential was in reverse proportion to the drug concentration. The addition of the drugs did not affect the MDD. It may be suggested that the co-administration of furosemide or torsemide and PN caused no interaction. The absence of such signs of unwanted interactions allowed for the co-administration of the mentioned loop diuretics and PN at each of the studied ratios.

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An In Vitro Analysis of the Effects of Intravenous Lipid Emulsion on Free and Total Local Anaesthetic Concentrations in Human Blood and Plasma

Critical Care Research and Practice ◽

10.1155/2014/236520 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7

Author(s):

Louise Ann Clark ◽

Jochen Beyer ◽

Andis Graudins

Keyword(s):

Blood Plasma ◽

Human Blood ◽

Local Anaesthetic ◽

Whole Blood ◽

Lipid Emulsion ◽

Equilibrium Dialysis ◽

Human Blood Plasma ◽

Intravenous Lipid Emulsion ◽

Vitro Effect

Background. Intravenous lipid emulsion (ILE) is recommended as a “rescue” treatment for local anaesthetic (LA) toxicity. A purported mechanism of action suggests that lipophilic LAs are sequestered into an intravascular “lipid-sink,” thus reducing free drug concentration. There is limited data available correlating the effects of ILE on LAs.Aims. To compare the in vitro effect of ILE on LA concentrations in human blood/plasma and to correlate this reduction to LA lipophilicity.Method. One of four LAs (bupivacaine-most lipophilic-4 mg/L, ropivacaine-6 mg/L, lignocaine-14 mg/L, and prilocaine-least lipophilic-7 mg/L) was spiked into plasma or whole blood. ILE or control-buffer was added. Plasma was centrifuged to separate ILE and total-LA concentration assayed from the lipid-free fraction. Whole blood underwent equilibrium dialysis and free-LA concentration was measured. Percent reduction in LA concentration from control was compared between the LAs and correlated with lipophilicity.Results. ILE caused a significant reduction in total and free bupivacaine concentration compared with the other LAs. Ropivacaine had the least reduction in concentration, despite a lipophilicity similar to bupivacaine. The reduction in LA concentration correlated to increasing lipophilicity when ropivacaine was excluded from analysis.Conclusion. In this first in vitro model assessing both free- and total-LA concentrations exposed to ILE in human blood/plasma, ILE effect was linearly correlated with increasing lipophilicity for all but ropivacaine.

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Effect of tannins in the rumen microbial growth measured by 32P incorporation

Proceedings of the British Society of Animal Science ◽

10.1017/s1752756200010498 ◽

2005 ◽

Vol 2005 ◽

pp. 138-138

Author(s):

P. B. Godoy ◽

I. C. S. Bueno ◽

S. L. S. Cabral Filho ◽

E. F. Nozella ◽

M. R. S. R Peçanha ◽

...

Keyword(s):

Polyethylene Glycol ◽

Phenolic Compounds ◽

Feed Intake ◽

Microbial Growth ◽

Protein Digestibility ◽

Binding Agent ◽

Sheep And Goats ◽

Synthetic Materials ◽

32P Incorporation

The phenolic compounds are substances which reduce feed intake, protein digestibility and reduce ruminal activity in sheep and goats. To reduce the effects of tannins a lot of synthetic materials, for example PEG (polyethylene glycol) is tested as tannin-binding agent, and let protein free for the digestibility. The aim of this work was to test the effect of tannins in the rumen microbial growth using the in vitro 32P incorporation technique.

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