Survival of lactococci during passage through mouse digestive tract

2003 ◽  
Vol 49 (11) ◽  
pp. 707-711 ◽  
Author(s):  
Hiromi Kimoto ◽  
Masaru Nomura ◽  
Miho Kobayashi ◽  
Koko Mizumachi ◽  
Takashi Okamoto
Keyword(s):  
Survival Rate ◽  
Lactococcus Lactis ◽  
Animal Health ◽  
In Vitro Test ◽  
Lactococcus Lactis Subsp ◽  
Mouse Intestine ◽  
Vitro Test ◽  
The Subject

One of the important properties of probiotics is the ability to survive in the intestine. There have been few studies on the probiotic property of lactococci, since they are formally not considered to be natural inhabitants of the intestine. To evaluate lactococci as probiotic bacteria, we investigated their ability to survive during gastric transit by in vitro and in vivo tests. When exposed to an in vitro simulated gastrointestinal environment, such as low pH and bile, only Lactococcus lactis subsp. lactis bv. diacetylactis N7 showed a moderate survival rate among the four strains tested. The tested strains were orally administered to mice, and intestinal passage of the ingested strains was monitored by two methods: antibiotics and PCR. Viable cells of strain N7 were recovered from feces within 24–48 h after administration but not at 72 h. Lactococcus lactis subsp. cremoris ATCC 19257, which had a poor survival rate in vitro test, was also detected at 12 h but not at 24 h. These results indicate that lactococci can reach the mouse intestine alive, but not colonize it. If administered daily, viable strain N7 may exist continuously in the intestine. The effect of strain N7 on intestinal microbial balance and on animal health will be the subject of a further study.Key words: Lactococcus, survival, gastrointestinal tract, probiotics.

In Vitro Toxicology Methods in Risk Assessment

1996 ◽  
Vol 24 (3) ◽  
pp. 325-331
Author(s):  
Iain F. H. Purchase
Keyword(s):  
Risk Assessment ◽  
Hazard Assessment ◽  
Human Health Risk ◽  
In Vitro Test ◽  
In Vitro Methods ◽  
New Concepts ◽  
Vitro Test

The title of this paper is challenging, because the question of how in vitro methods and results contribute to human health risk assessment is rarely considered. The process of risk assessment usually begins with hazard assessment, which provides a description of the inherent toxicological properties of the chemical. The next step is to assess the relevance of this to humans, i.e. the human hazard assessment. Finally, information on exposure is examined, and risk can then be assessed. In vitro methods have a limited, but important, role to play in risk assessment. The results can be used for classification and labelling; these are methods of controlling exposure, analogous to risk assessment, but without considering exposure. The Ames Salmonella test is the only in vitro method which is incorporated into regulations and used widely. Data from this test can, at best, lead to classification of a chemical with regard to genotoxicity, but cannot be used for classification and labelling on their own. Several in vitro test systems which assess the topical irritancy and corrosivity of chemicals have been reasonably well validated, and the results from these tests can be used for classification. The future development of in vitro methods is likely to be slow, as it depends on the development of new concepts and ideas. The in vivo methods which currently have reasonably developed in vitro alternatives will be the easiest to replace. The remaining in vivo methods, which provide toxicological information from repeated chronic dosing, with varied endpoints and by mechanisms which are not understood, will be more difficult to replace.

Animal Models and Alternatives in the Quality Control of Vaccines: Are In Vitro Methods or In Vivo Methods the Scientific Equivalent of the Emperor's New Clothes?

1995 ◽  
Vol 23 (1) ◽  
pp. 61-73
Author(s):  
Coenraad Hendriksen ◽  
Johan van der Gun
Keyword(s):  
Quality Control ◽  
Test Methods ◽  
In Vitro Test ◽  
Large Numbers ◽  
Alternative Approach ◽  
Inactivated Vaccines ◽  
Vitro Test

In the quality control of vaccine batches, the potency testing of inactivated vaccines is one of the areas requiring very large numbers of animals, which usually suffer significant distress as a result of the experimental procedures employed. This article deals with the potency testing of diphtheria and tetanus toxoids, two vaccines which are used extensively throughout the world. The relevance of the potency test prescribed by the European Pharmacopoeia monographs is questioned. The validity of the potency test as a model for the human response, the ability of the test to be standardised, and the relevance of the test in relation to the quality of the product are discussed. It is concluded that the potency test has only limited predictive value for the antitoxin responses to be expected in recipients of these toxoids. An alternative approach for estimating the potency of toxoid batches is discussed, in which a distinction is made between estimation of the immunogenic potency of the first few batches obtained from a seed lot and monitoring the consistency of the quality of subsequent batches. The use of animals is limited to the first few batches. Monitoring the consistency of the quality of subsequent batches is based on in vitro test methods. Factors which hamper the introduction and acceptance of the alternative approach are considered. Finally, proposals are made for replacement, reduction and/or refinement (the Three Rs) in the use of animals in the routine potency testing of toxoids.

scholarly journals Use of Tannin-Containing Plants as Antimicrobials Influencing the Animal Health

2022 ◽  
Vol 45 (2) ◽  
pp. 33-40
Author(s):  
Mohammed M Dakheel ◽  
Afnan A Al-Mnaser ◽  
Jessica Quijada ◽  
Martin J Woodward ◽  
Caroline Rymer
Keyword(s):  
Nutritional Quality ◽  
Condensed Tannins ◽  
Animal Health ◽  
Degree Of Polymerization ◽  
Gram Negative Bacteria ◽  
Animal Feeding ◽  
The Subject

The antimicrobial effects of diverse tannin-containing plants, particularly condensed tannins (CTs) produced from various plants, are the subject of this study. CT components can be determined using CT-specific procedures such the HCl-Butanol Acetone assay, Thiolysis reaction, and HPLC/MS analysis. These methods indicate CT contents, including mean degree of polymerization, the procyanidins and prodelphinidins ratio (PC/PD%), the isomers of trans- and cis-, and CT concentration. Tannin-containing plants possess antibacterial action, which can be attributed to their protein linkage technique, and tannin-type variations, particularly CTs extract and their PC/PD%. The effects of CT components on the development of Gram-positive and Gram-negative bacteria have been documented for their relative PC/PD%; this is regarded to be a key predictor of tannin characteristics in terms of antimicrobials. In conclusion, tannins, more specific CT compositions, have significant impacts on in vivo trials of animal productions and utilization of metabolites and fermentation in vitro experiments. These findings need further investigations to fully understand how CT-types act on animal feeding in terms of enhanced nutritional quality of animal diets, which may have implications for human and animal health.

The antibacterial activity expressed in vitro and in vivo by Lactococcus lactis subsp. lactis CNRZ 1427 against Salmonella sp.

2015 ◽  
Vol 4 (5) ◽  
pp. 240-246
Author(s):  
Menad Najett ◽  
Chougrani Fadelaa ◽  
Moghtet Snoussi ◽  
Cheriguene Abderrahim
Keyword(s):  
Antibacterial Activity ◽  
Lactococcus Lactis ◽  
Bile Salts ◽  
Therapeutic Agent ◽  
Lactococcus Lactis Subsp ◽  
Beneficial Effects ◽  
Gastrointestinal Conditions ◽  
Therapeutic Possibilities

  The present study focused on the beneficial effects of Lactococcus lactis subsp lactis CNRZ 1427 with possible use as a therapeutic agent against Sal-monella sp.; also we have proposed different therapeutic possibilities of our situation against a pathogen Salmonella sp. We have conducted two tests In Vitro and In Vivo; where it is noted that treatment in the presence of this lac-tic strain is effective since it causes a remarkable decrease of the pathogen agent. At the end, the effectiveness of this lactic strain was confirmed by testing for resistance to gastrointestinal conditions (pH, bile salts and diges-tive enzymes).

scholarly journals Tablet Scoring: Current Practice, Fundamentals, and Knowledge Gaps

2019 ◽  
Vol 9 (15) ◽  
pp. 3066 ◽  
Author(s):  
Emmanuel Reginald Jacques ◽  
Paschalis Alexandridis
Keyword(s):  
Prescription Drugs ◽  
In Vitro Test ◽  
Dose Administration ◽  
Solid Dosage ◽  
Non Invasive ◽  
Health Care Practitioners ◽  
Tablet Splitting ◽  
Vitro Test

Oral solid dosage formulations and/or tablets have remained the preferred route of administration by both patients and health care practitioners. Oral tablets are easy to administer, they are non-invasive and cause less risk adversity. Because of the lack of commercially available tablet dose options, tablets are being split or partitioned by users. Tablet scoring refers to the breakage of a tablet to attain a desired efficacy dose and is an emerging concept in the pharmaceutical industry. The primary reason for the tablet scoring practice is to adjust the dose: dose tapering or dose titrating. Other reasons for tablet partitioning are to facilitate dose administration, particularly among the pediatric and the geriatric patient population, and to mitigating the high cost of prescription drugs. The scope of this review is to: (1) evaluate the advantages and inconveniences associated with tablet scoring/portioning, and (2) identify factors in the formulation and the manufacturing of tablets that influence tablet splitting. Whereas tablet partitioning has been a common practice, there is a lack of understanding regarding the fundamentals underpinning the performance of tablets with respect to splitting. Several factors can influence tablet partitioning: tablet size, shape, and thickness. A requirement has recently been set by the European Pharmacopoeia and the U.S. Food and Drug Administration for the uniformity of mass of subdivided tablets. For breaking ease, an in-vivo reference test and a routinely applicable in-vitro test need to be established.

Characteristics and Biocompatibility of the Hydroxyapatite Based Two Ternary Biocomposites

2016 ◽  
Vol 720 ◽  
pp. 130-140
Author(s):  
Berrak Bulut ◽  
Ziya Engin Erkmen ◽  
Eyup Sabri Kayali
Keyword(s):  
Mechanical Properties ◽  
Physical And Mechanical Properties ◽  
Secondary Phase ◽  
In Vitro Test ◽  
Compression Tests ◽  
Vitro Test ◽  
Dental Applications ◽  
The Ideal

Hydroxyapatite (HA) is a very popular bioceramic for orthopedic and dental applications. Although HA has excellent biocompatibility, its inferior mechanical properties make it unsuitable for load-bearing implant applications. Therefore, HA should be strengthened by a secondary phase for robust mechanical properties. The aim of this study was to compare the properties of HA-Al2O3 (HAC) and HA-ZrO2 (HZC) composites with the addition of 5 and 10 wt% commercial inert glass (CIG); independently. The mixture powders were pressed and then, the pellets were sintered between 1000-1300 °C for 4 hours. Microstructural characterizations were carried out using SEM + EDS and XRD, while hardness and compression tests were done to measure mechanical properties. In order to investigate the biocompatibility behavior of the samples in vitro and in vivo tests were performed. The mechanical properties of HAC composites increased with rising CIG content and increasing sintering temperature. For HZC composites, increasing CIG content caused an elevation in hardness and a decrease in compressive strength values at 1300 °C. The composites having the best physical and mechanical properties also showed improved bioactive properties at in vitro test. In this study, the ideal composite was selected as HZC5 sintered at 1200 °C depending on the microstructure, mechanical and biocompatibility properties.

scholarly journals Prediction of in Vivo Cytotoxicity of Chemotherapeutic Agents by Their Effect on Malignant Leukocytes in Vitro

Blood ◽  
1967 ◽  
Vol 30 (2) ◽  
pp. 176-188 ◽  
Author(s):  
MARTIN J. CLINE
Keyword(s):  
Test System ◽  
Chemotherapeutic Agents ◽  
Response To Treatment ◽  
In Vitro Test ◽  
Malignant Cells ◽  
Vitro Test ◽  
In Vitro Effects ◽  
In Vivo Cytotoxicity

Abstract In order to develop a test system for predicting the response to chemotherapeutic agents, leukocytes from patients with leukemia and leukolymphosarcoma were cultured in vitro and the effect of several drugs on the incorporation of H3-uridine into ribonucleic acid was measured. Cortisol, vincristine and cytosine arabinoside at concentrations near the therapeutic range produced inhibition of H3-uridine incorporation in sensitive leukocytes. The in vitro effects of 6-mercaptopurine and methotrexate were variable. In 39 trials on 25 patients with leukemia or lymphosarcoma, the in vitro test was used successfully to predict the response to treatment with prednisone and vincristine. It was concluded that the in vitro test system can predict the in vivo cytotoxicity of certain drugs for malignant cells, although it cannot be used to predict the likelihood of the induction of remissions with these drugs.

IN VITRO DEMONSTRATION OF "HEPARIN REBOUND"

1987 ◽  
Author(s):  
C Taylor ◽  
R F Baugh
Keyword(s):  
Whole Blood ◽  
Cardiovascular Surgery ◽  
Anticoagulant Activity ◽  
Blood Levels ◽  
In Vitro Test ◽  
Neutralizing Activity ◽  
Vitro Test ◽  
The Stability

"Heparin rebound", the in vivo appearance of measurable heparin anticoagulant activity following theapparent neutralization of heparin by protamine, hasbeen a problem sporadically associated with the use of heparin in cardiovascular surgery. A number of mechanisms have been proposed to explain rebound, and to some extent each may contribute to the phenomena. As yet no reliable, predictable method has been demonstrated for measuring, reproducing or quantifying "heparin rebound".We have demonstrated and measured the appearance of heparin anticoagulant activity following neutralization with protamine in citrated whole blood. The reappearance of heparin anticoagulant activity was associated with a rapid loss of protamine. The loss of protamine followed 1st order enzyme kinetics, and was indicative of the action of an enzyme. The anticoagulant activity which eappeared could be titrated againwith protamine. The loss of protamine neutralizing activity, in whole blood, could be followed by titration with heparin using a recalcified activated clotting time. The rate of loss varied with both individual blood donors and with the type and source of protamine. The rate of loss of protamine was great enough to influence in. vivo heparin/protamine neutralization ratios, i.e. at 4 units of heparin/ml, 1 unit/ml anticoagulant activity was routinely recovered within 30 minutes following initial neutralization. The indications for cardiovascular surgery are:1)the in vivo neutralization ratio should be adjusted to account for loss of protamine activity, 2) the higherthe blood levels of heparin used during surgery, themore significant the potential for heparin rebound, and 3) protamines may be evaluated in an in vitro test which measures the stability of protamine neutralizing activity in whole blood.

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