Comment on the paper, “Growth of yeast cultures as in vitro model for investigating homœopathic remedies”

1985 ◽  
Vol 74 (02) ◽  
pp. 93-96 ◽  
Author(s):  
Rose D. Baker ◽  
C.W. Smith
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Growth Rate ◽  
In Vitro Model ◽  
Mean Value ◽  
Statistical Test ◽  
Yeast Cultures ◽  
The Mean ◽  
Vitro Model

SummaryA recent paper by Steffen1 repeating earlier work by Jones et al.2 failed to confirm any effect of potencies of Pulsatilla on the growth rate of cultures of Saccharomyces cerevisiae which had previously been reported.We find that using a more specific statistical test on the results given by Steffen1 it can be shown that these results contain almost the same periodicity with potency that Jones et al.2 reported, although only corresponding to a variation of ±1.5% about the mean value.

scholarly journals Experimental Solution of Chitosan and Nanochitosan on Wettability in Root Dentine: In Vitro Model Prior Regenerative Endodontics

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Fernando Arias Alvarado ◽  
Maira Rivero Iriarte ◽  
Freddy Jordan Mariño ◽  
Sara Quijano-Guauque ◽  
León D. Pérez ◽  
...  
Keyword(s):  
In Vitro Model ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Hypochlorous Acid ◽  
Mean Value ◽  
Cellular Interaction ◽  
Regenerative Endodontics ◽  
Indirect Association ◽  
Vitro Model

Context. The wettability of the chemically modified dentin substrate is a condition that intervenes in dentin-vascular and cellular interaction across regenerative endodontics. Aims. To compare the effect of CS and CSnp on the wettability in root dentine with other irrigation protocols with an experimental in vitro model prior regenerative endodontics. Methods and Material. An in vitro experimental study that included eighty hemisected human root distributed into 8 groups: G1- distilled water; G2- 1% NaOCl/17% EDTA; G3- hypochlorous acid 0.025% HOCl, G4- 1% NaOCl/0.025% HOCl/17% EDTA, G5- 0.2 g/100 mL CS, G6- 1% NaOCl/0.2 g/100 mL CS, G7- CSnp, and G8- 1% NaOCl/CSnp. The wettability analysis calculated the contact angle (θ) between a drop of a blood-like and root dentinal surface; topographic characterization with scanning electron microscopy (SEM) quantified the diameter and number of tubules per area; spectroscopy infrared analyses (IR-S) identified chemical changes in the inorganic (phosphate/carbonate) and organic phase (amide/methyl). Statistical analysis: a linear mixed model, Kruskal–Wallis, and Holm–Bonferroni correction ( P  < 0.05) were used. Results. Significantly higher wettability for G2 (27.1 ( P  = 0.0001)) was found. A mean value of 67°±°for experimental groups ( P  = 0.07) was found, and we did not identify differences between them. The SEM identified greater tubular opening and erosion for G4 and greater dentinal permeability per area for NaOCl/CS. IR-S identified dentinal organic integrity with NaOCl-CS/CSnp compared to organic reduction promoted for NaOCl/EDTA. Conclusions. This in vitro dentin determined an indirect association between the wettability and organic contents. The oxidative effect of NaOCl could be neutralized by CS-CSnp, and consequently, the wettability of the substrate decreases.

scholarly journals Linezolid Compared with Eperezolid, Vancomycin, and Gentamicin in an In Vitro Model of Antimicrobial Lock Therapy for Staphylococcus epidermidis Central Venous Catheter-Related Biofilm Infections

2003 ◽  
Vol 47 (10) ◽  
pp. 3145-3148 ◽  
Author(s):  
John Curtin ◽  
Martin Cormican ◽  
Gerard Fleming ◽  
John Keelehan ◽  
Emer Colleran
Keyword(s):  
Central Venous Catheter ◽  
Staphylococcus Epidermidis ◽  
In Vitro Model ◽  
Physiological Saline ◽  
Venous Catheter ◽  
Saline Control ◽  
Central Venous ◽  
The Mean ◽  
Vitro Model

ABSTRACT Central venous catheter (CVC)-related infection (CVC-RI) is a common complication of CVC use. The most common etiological agents of CVC-RI are gram-positive organisms, in particular, staphylococci. An in vitro model for the formation of biofilms by Staphylococcus epidermidis ATCC 35984 on polyurethane coupons in a modified Robbins device was established. Biofilm formation was confirmed by electron microscopy and was quantified by determination of viable counts. Mueller-Hinton broth was replaced with sterile physiological saline (control) or a solution of vancomycin (10 mg/ml), gentamicin (10 mg/ml), linezolid (2 mg/ml), or eperezolid (4 mg/ml). Viable counts were performed with the coupons after exposure to antimicrobials for periods of 24, 72, 168, and 240 h. The mean viable count per coupon following establishment of the biofilm was 4.6 × 108 CFU/coupon, and that after 14 days of exposure to physiological saline was 2.5 × 107 CFU/coupon. On exposure to vancomycin (10 mg/ml), the mean counts were 2.5 × 107 CFU/coupon at 24 h, 4.3 × 106 CFU/coupon at 72 h, 1.4 × 105 CFU/coupon at 168 h, and undetectable at 240 h. With gentamicin (10 mg/ml) the mean counts were 2.7 × 107 CFU/coupon at 24 h, 3.7 × 106 CFU/coupon at 72 h, 8.4 × 106 CFU/coupon at 168 h, and 6.5 × 106 CFU/coupon at 240 h. With linezolid at 2 mg/ml the mean counts were 7.1 × 105 CFU/coupon at 24 h and not detectable at 72, 168, and 240 h. With eperezolid (4 mg/ml) no viable cells were recovered after 168 h. These data suggest that linezolid (2 mg/ml) and eperezolid (4 mg/ml) achieve eradication of S. epidermidis biofilms more rapidly than vancomycin (10 mg/ml) and gentamicin (10 mg/ml).

Peri-Implant Strain in an In Vitro Model

2015 ◽  
Vol 41 (5) ◽  
pp. 532-537 ◽  
Author(s):  
Souheil Hussaini ◽  
Tritala K. Vaidyanathan ◽  
Abhinav P. Wadkar ◽  
Firas A. Al Quran ◽  
David Ehrenberg ◽  
...  
Keyword(s):  
In Vitro Model ◽  
Mechanical Test ◽  
Statistical Treatment ◽  
Test System ◽  
Strain Gages ◽  
Different Types ◽  
Bone Atrophy ◽  
The Mean ◽  
Vitro Model

An in vitro experimental model was designed and tested to determine the influence that peri-implant strain may have on the overall crestal bone. Strain gages were attached to polymethylmethacrylate (PMMA) models containing a screw-type root form implant at sites 1 mm from the resin-implant interface. Three different types of crown superstructures (cemented, 1-screw [UCLA] and 2-screw abutment types) were tested. Loading (1 Hz, 200 N load) was performed using a MTS Mechanical Test System. The strain gage data were stored and organized in a computer for statistical treatment. Strains for all abutment types did not exceed the physiological range for modeling and remodeling of cancellous bone, 200–2500 μɛ (microstrain). For approximately one-quarter of the trials, the strain values were less than 200 μɛ the zone for bone atrophy. The mean microstrain obtained was 517.7 μɛ. In conclusion, the peri-implant strain in this in vitro model did not exceed the physiologic range of bone remodeling under axial occlusal loading.

scholarly journals Reticulocyte rigidity and passage through endothelial-like pores

Blood ◽  
1991 ◽  
Vol 78 (11) ◽  
pp. 3037-3042 ◽  
Author(s):  
RE Waugh
Keyword(s):  
Mechanical Properties ◽  
Bone Marrow ◽  
In Vitro Model ◽  
Gradient Centrifugation ◽  
The Mean ◽  
The Difference ◽  
Vitro Model ◽  
Mean Time ◽  
Endothelial Pores

The importance of cell rigidity in regulating the release of reticulocytes from the bone marrow has been investigated in a model system. Reticulocytes were obtained from phlebotomized rabbits and separated from whole blood by discontinuous density gradient centrifugation. The mechanical properties of the cells were tested. Using single-cell micromechanical techniques, the membrane elastic rigidity and the viscoelastic response of reticulocyte and mature cell populations were measured. The reticulocyte membranes were more rigid than the mature membranes, but the reticulocyte properties were heterogeneous, and some cells exhibited behavior indistinguishable from the mature cells. The mean time constant for viscoelastic recovery was the same for reticulocytes as for mature cells, but the variability within the reticulocyte population was greater. The possible influence of this increased rigidity on cell egress from the bone marrow was tested using an in vitro model of the thin endothelial pores found within the marrow. A silicon wafer approximately 0.1 microns in thickness and containing a small (1.2-microns diameter) pore in its center was cemented over the tip of a large (15.0-microns ID) micropipette. The passage of cells through the pore was observed as a function of the pressure across the pore. Consistent with the difference in mechanical properties, the reticulocytes required greater pressures (as great as 4.0 mm Hg compared with less than 1.0 mm Hg) and took longer to traverse the pore. These measurements support the postulate that deformability is important in the regulation of the release of cells from bone marrow.

scholarly journals Reticulocyte rigidity and passage through endothelial-like pores

Blood ◽  
1991 ◽  
Vol 78 (11) ◽  
pp. 3037-3042 ◽  
Author(s):  
RE Waugh
Keyword(s):  
Mechanical Properties ◽  
Bone Marrow ◽  
In Vitro Model ◽  
Gradient Centrifugation ◽  
The Mean ◽  
The Difference ◽  
Vitro Model ◽  
Mean Time ◽  
Endothelial Pores

Abstract The importance of cell rigidity in regulating the release of reticulocytes from the bone marrow has been investigated in a model system. Reticulocytes were obtained from phlebotomized rabbits and separated from whole blood by discontinuous density gradient centrifugation. The mechanical properties of the cells were tested. Using single-cell micromechanical techniques, the membrane elastic rigidity and the viscoelastic response of reticulocyte and mature cell populations were measured. The reticulocyte membranes were more rigid than the mature membranes, but the reticulocyte properties were heterogeneous, and some cells exhibited behavior indistinguishable from the mature cells. The mean time constant for viscoelastic recovery was the same for reticulocytes as for mature cells, but the variability within the reticulocyte population was greater. The possible influence of this increased rigidity on cell egress from the bone marrow was tested using an in vitro model of the thin endothelial pores found within the marrow. A silicon wafer approximately 0.1 microns in thickness and containing a small (1.2-microns diameter) pore in its center was cemented over the tip of a large (15.0-microns ID) micropipette. The passage of cells through the pore was observed as a function of the pressure across the pore. Consistent with the difference in mechanical properties, the reticulocytes required greater pressures (as great as 4.0 mm Hg compared with less than 1.0 mm Hg) and took longer to traverse the pore. These measurements support the postulate that deformability is important in the regulation of the release of cells from bone marrow.

Growth of yeast cultures as in vitro model for investigating homœopathic medicines

1985 ◽  
Vol 74 (03) ◽  
pp. 132-140 ◽  
Author(s):  
William A. Steffen
Keyword(s):  
Cell Cultures ◽  
In Vitro Model ◽  
Total Cell ◽  
Yeast Cells ◽  
Exponential Growth Phase ◽  
Malt Extract ◽  
Remedial Action ◽  
Yeast Cultures ◽  
Vitro Model

AbstractThe question of a sensitive response in the growth of yeast cell cultures to treatments with homœopathic dilutions (potencies), has been raised in a number of recent publications,1,2,3. A further set of growth trials with this model performed at our Institute are reported here.The actions of 8x to 16x decimal potencies of AgNO3, CuSO4, HgCl2, and NaCl on the growth of cell cultures of Schizosaccharomyces pombe were investigated. This included a set of trials with experimental poisoning of the cells by toxic levels of CuSO4 and subsequent study of the remedial action by potencies of the same substance.Yeast cells were grown in batch culture in a glucose/malt extract medium. Growth was interrupted shortly before the end of the exponential growth phase and total cell concentrations were assessed by means of a Coulter Counter. The obtained data were subjected to statistical analysis. Each treatment range was tested in three separate trials.The results obtained failed to indicate any response in the growth rate of Sch. pombe to the potency treatments.

Iohexol Transmembrane Clearance during Modeled Continuous Renal Replacement Therapy

2015 ◽  
Vol 39 (1-3) ◽  
pp. 188-192
Author(s):  
J. Michael Yardman-Frank ◽  
Renee-Claude Mercier ◽  
Craig S. Wong ◽  
A. Mary Vilay
Keyword(s):  
Molecular Weight ◽  
Renal Replacement Therapy ◽  
Continuous Renal Replacement Therapy ◽  
Replacement Therapy ◽  
In Vitro Model ◽  
Ultrafiltration Rate ◽  
Continuous Hemofiltration ◽  
The Mean ◽  
Vitro Model

Background/Aims: Urea clearance during continuous renal replacement therapy (CRRT) is not representative of middle molecular weight solute clearances. We aimed to characterize iohexol, molecular weight 821 Da, clearance during continuous hemofiltration (CH) and continuous hemodialysis (CHD). Methods: Using an in vitro model, iohexol sieving coefficients (SC) and saturation coefficients (SA) were determined with the M100 membrane at ultrafiltration/dialysate rates of 1, 2, 3, 4, and 6 l/h. Iohexol transmembrane clearance was calculated using the measured SC and SA. Results: During CH, the value of iohexol SC remained approximately 1 at all ultrafiltration rates studied. In contrast, during CHD iohexol the mean SA was 1.02 ± 0.05 at a dialysate rate 1 l/h and decreased significantly with higher dialysate rates to a mean SA of 0.57 ± 0.12 at a dialysate rate of 6 l/h. Conclusions: At higher effluent flow rates, CH was more effective in removing iohexol than CHD. CH transmembrane clearance of iohexol appears to approximate the ultrafiltration rate.

scholarly journals Saccharomyces Cerevisiae Var Boulardii CNCM I–1079 Reduces Expression of Genes Involved in Inflammatory Response in Porcine Cells Challenged by Enterotoxigenic E. Coli and Influences Bacterial Communities in an In Vitro Model of the Weaning Piglet Colon

Antibiotics ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1101
Author(s):  
Raphaële Gresse ◽  
Juan J. Garrido ◽  
Angeles Jiménez-Marín ◽  
Sylvain Denis ◽  
Tom Van de Wiele ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Inflammatory Response ◽  
In Vitro Model ◽  
Infectious Agent ◽  
Enterotoxigenic Escherichia Coli ◽  
Dependent Manner ◽  
Bacterial Strains ◽  
Expression Of Genes ◽  
Vitro Model

Enterotoxigenic Escherichia coli (ETEC) is the main infectious agent responsible for piglet post-weaning diarrhea with high mortality rates. Antimicrobials represent the current principal strategy for treating ETEC infections in pig farms, but the occurrence of multi-resistant bacterial strains has considerably increased in the last decades. Thus, finding non-antibiotic alternatives becomes a real emergency. In this context, we investigated the effect of a live yeast strain, Saccharomyces cerevisiae var boulardii CNCM I-1079 (SB) in an in vitro model of the weaning piglet colon implemented with a mucus phase (MPigut-IVM) inoculated with ETEC and coupled with an intestinal porcine cell line IPI-2I. We showed that SB was able to modulate the in vitro microbiota through an increase in Bacteroidiaceae and a decrease in Prevotellaceae families. Effluents collected from the SB treated bioreactors were able to mitigate the expression level of genes encoding non-gel forming mucins, tight junction proteins, innate immune pathway, and pro-inflammatory response in IPI-2I cells. Furthermore, SB exerted a significant protective effect against ETEC adhesion on porcine IPEC-J2 intestinal cells in a dose-dependent manner and showed a positive effect on ETEC-challenged IPEC-J2 by lowering expression of genes involved in pro-inflammatory immune responses. Our results showed that the strain SB CNCM I-1079 could prevent microbiota dysbiosis associated with weaning and protect porcine enterocytes from ETEC infections by reducing bacterial adhesion and modulating the inflammatory response.

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