scholarly journals Protocol for the Isolation of Stratum Corneum from Pig Ear Skin: Evaluation of the Trypsin Digestion Conditions

2021 ◽  
Vol 4 (4) ◽  
pp. 80
Author(s):  
Tânia Moniz ◽  
Sofia A. Costa Lima ◽  
Salette Reis
Keyword(s):  
Stratum Corneum ◽  
Histological Analysis ◽  
Simple Procedure ◽  
Storage Period ◽  
Isolation Procedure ◽  
Trypsin Digestion ◽  
Medical Procedures ◽  
Experimental Conditions ◽  
Effective Barrier ◽  
Period Data

Stratum corneum (SC) represents the outermost layer of the skin, being an effective barrier against the entry of molecules and pathogens. Skin research has given particular focus to SC as it hampers effective drug delivery for cosmetical and therapeutical purposes. Following recommendations to develop alternative models to animals, the SC isolated from skin obtained from medical procedures or from pigs has gained extensive attention. Yet, there is still missing a standard and simple procedure accepted within the scientific community to avoid application of different isolated SC methodologies, a fact that may hamper progress in skin research. Considering this challenge, the present study evaluated different experimental conditions aiming to establish a useful and sustainable solvent-free procedure for the obtention of a realistic SC model. The studied trypsin digestion parameters included concentration, incubation period and temperature. Isolated SC was characterized using histological analysis and calcein’s permeability, after the procedure and during a 6-week storage period. Data recommend trypsin digestion at 4 °C for 20 h as the most effective procedure to isolate SC from pig ear skin. This work contributes to standardize the SC isolation procedure, and to obtain a valuable and reliable SC mimetic model for skin drug development.

scholarly journals Direct Specific Heat Measurements on Solutions of Volatile Solutes by Flow Microcalorimetry: Partial Molal Heat Capacity of Benzene in Water at 25 °C

1975 ◽  
Vol 53 (23) ◽  
pp. 3634-3636 ◽  
Author(s):  
Carmel Jolicoeur ◽  
Patrick Picker ◽  
Gérald Perron
Keyword(s):  
Heat Capacity ◽  
Specific Heat ◽  
Simple Procedure ◽  
Specific Heat Measurement ◽  
Experimental Conditions ◽  
Heat Measurement ◽  
Flow Microcalorimetry ◽  
Partial Molal Heat Capacity

The direct specific heat measurement on aqueous benzene solutions by flow microcalorimetry have been repeated to elucidate discrepancies among earlier results. Through extensive variations of experimental conditions, the origin of difficulties encountered previously has been investigated and a simple procedure has been devised to circumvent problems inherent to this particular type of measurements.

Aerodynamic Performance of a Transonic Turbine Guide Vane With Trailing Edge Coolant Ejection: Part II — Numerical Approach

1994 ◽  
Author(s):  
V. Michelassi ◽  
F. Martelli ◽  
J. Amecke
Keyword(s):  
Guide Vane ◽  
Simple Procedure ◽  
Numerical Approach ◽  
Marginal Effect ◽  
Grid Refinement ◽  
Trailing Edge ◽  
Experimental Conditions ◽  
Mach Number Distribution ◽  
Turbine Guide Vane ◽  
Transonic Turbine

The effect of coolant ejection from the trailing edge of a turbine blade is studied by means of numerical simulation codes. Two solvers based on explicit and implicit algorithms with and without multigridding are used in connection with H, HOH and HC grid types. A simple procedure to model the coolant jet at the trailing edge of the blade is presented which does not require excessive grid refinement. The features of the different approaches are discussed in terms of isentropic Mach number distribution on the blade, base pressures and wake profiles at various exit Mach numbers and coolant flow rates which match the experimental conditions. The coolant ejection effect on the shock pattern is discussed. The trailing edge ejection is found to have a marginal effect on the wake shape and on the measured and computed base pressures.

Experimental determination of the instrumental broadening in the Bragg–Brentano geometry

1994 ◽  
Vol 9 (3) ◽  
pp. 180-186 ◽  
Author(s):  
P. Scardi ◽  
L. Lutterotti ◽  
P. Maistrelli
Keyword(s):  
High Resolution ◽  
Experimental Determination ◽  
Simple Procedure ◽  
Line Broadening ◽  
Experimental Conditions ◽  
Analytical Functions ◽  
Profile Fitting ◽  
Diffraction Angle

A simple procedure was devised for the preparation of a standard KCl powder to be used for the experimental determination of the instrumental profile in the Bragg–Brentano geometry. The standard was tested on several diffractometers, and narrow Bragg reflections in the range 28°–132° were recorded adopting various experimental conditions. Profiles were modeled with analytical functions, to describe the trend of width and shape of the instrumental profile as a function of the diffraction angle. Some indications were given to perform reliable profile fitting and line broadening analysis; a high resolution setup, obtained by employing narrow slits, large goniometer radius, and a monochromator in the diffracted beam, gives narrow reflections, even though the intensity of the diffracted beam is considerably reduced. The choice of these experimental conditions, which can be achieved using the majority of the commercial instruments, leads to symmetrical profiles, even at relatively low angle (2Θ=28°), which are highly recommended for reliable profile fitting and line broadening analysis.

scholarly journals Conservation of sausages utilizing chitosan biofilm

2016 ◽  
Vol 7 (1) ◽  
pp. 42
Author(s):  
Gelcimara Engel ◽  
Solange Pizato ◽  
Daneysa Lahis Kalschne ◽  
Rosana Aparecida Da Silva-Buzanello ◽  
Sascha Habu ◽  
...  
Keyword(s):  
Inhibitory Action ◽  
Film Formation ◽  
Storage Period ◽  
Experimental Conditions ◽  
Antifungal Effect ◽  
Significant Difference ◽  
Effective Inhibition ◽  
Thermotolerant Coliforms ◽  
Coagulase Positive Staphylococcus

Use of biofilms in food enable increase of shelf life and ensure the conservation thereof. Chitosan has been used on obtainment of biofilms due its excellent properties of antimicrobial, antifungal, permeable and resistant film formation. The aim of this study was to evaluate the application effect of chitosan biofilms on conservation of sausages vacuum-packed or bulk packaging, stored at 10 °C for 10 days. For biofilm obtaining, chitosan (85% of deacetylation) was dissolved in acetic acid (0.5 mol L-1), at concentrations of 1% (T1) and 2% (T2). Sausages produced in industrial line were coating with T1 and T2 to immersion, stored at vacuum-packed or bulk packaging, and compared to a control (T3, without coating). Microbiologic analyses to determination of total and thermotolerant coliforms, mesophilic aerobic count, coagulase-positive Staphylococcus, and molds and yeasts were carried out during the storage at 10 °C, at times of 0, 14, 21 and 28 days, in order to study the antimicrobial and antifungal behavior of biofilm on the sausage. The biofilm showed no inhibitory action for mesophilic aerobic in all samples during the storage period. In molds and yeasts analyses were no significant difference between the samples T1, T2 and T3, for the vacuum packed sausages, indicating that the biofilm chitosan showed antifungal properties in the studied conditions. Further, in yeast count was observed that T2 was more effective inhibition than T1. In all experimental conditions, the coagulase-positive Staphylococcus count, and determination of total and thermotolerant coliforms showed values lower than 2 CFU g-1 and 0.3 MPN g-1, respectively. Application of chitosan biofilms in sausages can result in antifungal effect when associated to vacuum packing.

Stratum Corneum Is an Effective Barrier to TiO2 and ZnO Nanoparticle Percutaneous Absorption

2009 ◽  
Vol 22 (5) ◽  
pp. 266-275 ◽  
Author(s):  
P. Filipe ◽  
J.N. Silva ◽  
R. Silva ◽  
J.L. Cirne de Castro ◽  
M. Marques Gomes ◽  
...  
Keyword(s):  
Stratum Corneum ◽  
Percutaneous Absorption ◽  
Zno Nanoparticle ◽  
Effective Barrier

Effect of Extrinsic Rearfoot Post Design on the Lateral-to-Medial Position and Velocity of the Center of Pressure

2006 ◽  
Vol 96 (5) ◽  
pp. 383-392 ◽  
Author(s):  
Joanne S. Paton ◽  
Simon K. Spooner
Keyword(s):  
Center Of Pressure ◽  
Foot Orthoses ◽  
Experimental Conditions ◽  
Period Data ◽  
Fourth Pair ◽  
Center Of Pressure Velocity

Findings from investigations of the effects of external forefoot and rearfoot posts added to foot orthoses have been inconclusive. This study was undertaken to examine the effects of rearfoot post design on the lateral-to-medial position and velocity of the center-of-pressure path. Four identical pairs of neutral-cast polypropylene orthotic shells were constructed; three pairs had a rearfoot post of specified design added. The fourth pair, the control, did not have a post added. Stance period data were broken down into four functional phases, and the statistically significant differences between the experimental conditions were calculated and analyzed. The addition of a rearfoot post to an orthotic shell affects center-of-pressure lateral-to-medial position and velocity. Although the effect of the post designs seemed to provide reasonably predictable changes in center-of-pressure position, the effect on center-of-pressure velocity was variable and inconsistent. The effect of the orthotic post was dependent on design and phase of gait. The addition of a rearfoot post and, specifically, the design of the post can probably be used to alter the center-of-pressure position and velocity. (J Am Podiatr Med Assoc 96(5): 383–392, 2006)

The Outermost Stratum Corneum Layer is an Effective Barrier Against Dermal Uptake of Topically Applied Micronized Titanium Dioxide

1999 ◽  
Vol 21 (6) ◽  
pp. 399-411 ◽  
Author(s):  
F. Pflücker ◽  
H. Hohenberg ◽  
E. Hölzle ◽  
T. Will ◽  
S. Pfeiffer ◽  
...  
Keyword(s):  
Titanium Dioxide ◽  
Stratum Corneum ◽  
Effective Barrier ◽  
Dermal Uptake

scholarly journals Interpretable Log Contrasts for the Classification of Health Biomarkers: a New Approach to Balance Selection

mSystems ◽  
2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Thomas P. Quinn ◽  
Ionas Erb
Keyword(s):  
High Throughput ◽  
High Throughput Sequencing ◽  
Simple Procedure ◽  
Feature Space ◽  
Cost Effective ◽  
Molecular Profile ◽  
Experimental Conditions ◽  
Effective Manner ◽  
Balance Analysis

ABSTRACT Since the turn of the century, technological advances have made it possible to obtain the molecular profile of any tissue in a cost-effective manner. Among these advances are sophisticated high-throughput assays that measure the relative abundances of microorganisms, RNA molecules, and metabolites. While these data are most often collected to gain new insights into biological systems, they can also be used as biomarkers to create clinically useful diagnostic classifiers. How best to classify high-dimensional -omics data remains an area of active research. However, few explicitly model the relative nature of these data and instead rely on cumbersome normalizations. This report (i) emphasizes the relative nature of health biomarkers, (ii) discusses the literature surrounding the classification of relative data, and (iii) benchmarks how different transformations perform for regularized logistic regression across multiple biomarker types. We show how an interpretable set of log contrasts, called balances, can prepare data for classification. We propose a simple procedure, called discriminative balance analysis, to select groups of 2 and 3 bacteria that can together discriminate between experimental conditions. Discriminative balance analysis is a fast, accurate, and interpretable alternative to data normalization. IMPORTANCE High-throughput sequencing provides an easy and cost-effective way to measure the relative abundance of bacteria in any environmental or biological sample. When these samples come from humans, the microbiome signatures can act as biomarkers for disease prediction. However, because bacterial abundance is measured as a composition, the data have unique properties that make conventional analyses inappropriate. To overcome this, analysts often use cumbersome normalizations. This article proposes an alternative method that identifies pairs and trios of bacteria whose stoichiometric presence can differentiate between diseased and nondiseased samples. By using interpretable log contrasts called balances, we developed an entirely normalization-free classification procedure that reduces the feature space and improves the interpretability, without sacrificing classifier performance.

Quality Changes of Marinated Tench (Tinca tinca) during Refrigerated Storage

2009 ◽  
Vol 15 (5) ◽  
pp. 513-521 ◽  
Author(s):  
Y. Özogul ◽  
E. Kuley ◽  
F. Özogul
Keyword(s):  
Fatty Acids ◽  
Storage Time ◽  
Storage Period ◽  
Tinca Tinca ◽  
E Coli ◽  
Microbiological Parameters ◽  
Period Data ◽  
Tench Tinca Tinca ◽  
And Staphylococcus Aureus ◽  
Total Bacteria

The quality control of marinated tench with sauce stored at 4 °C was investigated in terms of sensory, chemical (total volatile basic nitrogen (TVB-N), trimethylamine (TMA), thiobarbituric values (TBA), peroxide value, free fatty acids, biogenic amines, fatty acids, and pH and microbiological parameters (total aerobic count, coliform, Escherichia coli, and Salmonella) during 6 months of storage. The use of alcohol vinegar and salt in marinated tench caused the TVB-N, TMA to decrease. The maximum TVB-N and TMA values were found to be 12.77 mg/100 g and 4.68 mg/100 g after 150 days and 180 days storage period, respectively. Oxidative rancidity in marinated tench was found to be low (2.81 mg MA/kg) and rancid flavor was not detected even after a storage period of 180 days. As storage time progressed, putrescine, cadaverine, and serotonine became the dominant amines. Salmonella, coliform, E. coli, and Staphylococcus aureus were not detected during the storage period of 6 months. Total bacteria count increased to 4.3 log CFU/g at the end of the storage period. Data obtained from this study showed that marinated tench can be stored for more than 6 months.

Defecation Rate of Three Tubificid Oligochaetes Found in the Sediment of Toronto Harbour, Ontario

1970 ◽  
Vol 27 (11) ◽  
pp. 1971-1982 ◽  
Author(s):  
A. G. Appleby ◽  
R. O. Brinkhurst
Keyword(s):  
Relative Abundance ◽  
Weight Change ◽  
Tubifex Tubifex ◽  
Optimum Temperature ◽  
Selective Feeding ◽  
Experimental Conditions ◽  
Defecation Rate ◽  
Limnodrilus Hoffmeisteri ◽  
Period Data ◽  
Abundance And Distribution

The defecation rate of three tubificids is affected by temperature but the effect differs from species to species. Information on defecation rate and weight change at each experimental temperature suggests an optimum temperature range of 14 C for Peloscolex multisetosus, 18 C for Tubifex tubifex, and greater than 20 C for Limnodrilus hoffmeisteri. Downward trends of defecation rate with time were recorded for P. multisetosus, but these were probably due to lowered activity prior to the observed mortality. Upward trends in defecation rate with time in L. hoffmeisteri may indicate continuing acclimation to experimental conditions beyond their 10- to 14-day duration, or a need to process increasing amounts of less nutritious mud because of selective feeding on the richer fractions at the beginning of the assay period. Data on the relative abundance and distribution of species in Toronto Harbour is used to estimate defecation rates of the tubificid populations in the field.

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