Search results for "Confocal laser scanning microscopy"

Post-extraction mesio-distal gap reduction assessment by confocal laser scanning microscopy - a clinical 3-month follow-up study

2017

[EN] AimThe aim of this 3-month follow-up study is to quantify the reduction in the mesio-distal gap dimension (MDGD) that occurs after tooth extraction through image analysis of three-dimensional images obtained with the confocal laser scanning microscopy (CLSM) technique. Materials and MethodsFollowing tooth extraction, impressions of 79 patients 1month and 72 patients 3months after tooth extraction were obtained. Cast models were processed by CLSM, and MDGD changes between time points were measured. ResultsThe mean mesio-distal gap reduction 1month after tooth extraction was 343.4m and 3months after tooth extraction was 672.3m. The daily mean gap reduction rate during the first term (bet…

Modulation of mitochondriotropic properties of cyanine dyes by in organello copper-free click reaction

2017

Cyanine (Cy) dyes show a general propensity to localize in polarized mitochondria. This mitochondriotropism was used to perform a copper-free click reaction in the mitochondria of living cells. The in organello reaction of dyes Cy3 and Cy5 led to a product that was easily traceable by Forster resonance energy transfer (FRET). As determined by confocal laser scanning microscopy, the Cy3-Cy5 conjugate showed enhanced retention in mitochondria, relative to that of the starting compounds. This enhancement of a favorable property can be achieved by synthesis in organello, but not outside mitochondria.

Effect of high hydrostatic pressure on extraction of B-phycoerythrin from Porphyridium cruentum: Use of confocal microscopy and image processing

2019

International audience; The aim of the study was to extract B-phycoerythrin from Porphyridium cruentum while preserving its structure. The high hydrostatic pressure treatments were chosen as extraction technology. Different methods have been used to observe the effects of the treatment: spectrophotometry and confocal laser scanning microscopy followed by image processing analysis. Image processing led to the generation of masks used for the identification of three clusters: intra, extra and intercellular. All methods showed that high hydrostatic pressure treatments between 50 and 500 MPa failed to extract B-phycoerythrin from Porphyridium cruentum cells. The fluorescence emission was negati…

Histotomography of the odontoblast processes at the dentine-enamel junction of permanent healthy human teeth in the confocal laser scanning microscope

1998

The translucency of teeth allows the non-destructive subsurface visualisation of their microstructure by confocal laser scanning microscopy (CLSM) at a level of about 150 μm below the surface. The dentine–enamel junction (DEJ) is accessible only directly adjacent to the cervix of the tooth. Therefore teeth have to be sectioned for studying marginal areas of the dental hard tissue. The potential of the technique for (pseudo) three-dimensional visualisation allows the study of an array of individual confocal images, the interpretation of which is similar to that of macroscopic tomographs (CT-scan, MRI). Additionally, the extended focus mode yields the overlay of individual confocal images in …

2018

Abstract Purpose To report on a case of recurrence of paraproteinemic keratopathy (PPK) associated with monoclonal gammopathy after bilateral penetrating keratoplasty. Observations Penetrating keratoplasty was performed on both eyes of a 45-year-old man due to bilateral progressive corneal stromal clouding. Recurrence of the corneal stromal opacities accompanied by a decrease in visual acuity was observed on slit-lamp examination already two years after penetrating keratoplasty. Confocal laser scanning microscopy (CLSM) of the corneal grafts performed three years after penetrating keratoplasty showed bilateral morphological changes identical to that found in the patient's corneas prior to p…

Strukturelle Veränderungen in säuregeätztem Schmelz im konfokalen Laser-Scanning-Mikroskop

1996

The aim of the present investigation was to elucidate structural alternations in enamel subjected to acid etch technique and treatment under remineralizing conditions by means of a new microscopy technique known as confocal laser scanning microscopy (CLSM). Blocks of enamel were treated with 37% phosphoric acid and exposed for 3 weeks to an oral environment. Tomographic CLSM images were subsequently obtained and compared with controls. CLSM proved to be a reliable, highly reproducible and simple method of qualitative assessment of structural changes occurring on the surface of enamel and in areas below the surface as deep as 100 microns or more. Structural alterations associated with acid a…

Effect of oxidoreduction potential and of gas bubbling on rheological properties and microstructure of acid skim milk gels acidified with glucono-del…

2009

Milk oxidoreduction potential was modified using gases during the production of a model dairy product and its effect on gel setting was studied. Acidification by glucono-delta-lactone was used to examine the physicochemistry of gelation and to avoid variations due to microorganisms sensitive to oxidoreduction potential. Four conditions of oxidoreduction potential were applied to milk: milk was gassed with air, nongassed, gassed with N(2), or gassed with N(2)H(2). The rheological properties and microstructure of these gels were determined using viscoelasticimetry, measurement of whey separation, and confocal laser scanning microscopy. It appeared that a reducing environment led to less-aggre…

Antibacterial properties and reduction of MRSA biofilm with a dressing combining polyabsorbent fibres and a silver matrix

2016

Objective: This study was designed to evaluate the antibacterial activity of a wound dressing which combines polyacrylate fibres and a silver lipido-colloid matrix (UrgoClean Ag, silver polyabsorbent dressing), against biofilm of methicillin-resistant Staphylococcus aureus (MRSA). Method: Samples of silver polyabsorbent dressing and the neutral form of this dressing (UrgoClean) were applied to biofilms of MRSA formed on a collagen I-coated surface, cultured for 24 hours. Different exposure times were tested (1, 2, 4 and 7 days) without dressing change. The biofilm reduction was quantified by using culture methods and by confocal laser scanning microscopy experiments. Results: The applicatio…

Development and viability of biofilms grown on experimental abutments mimicking dental implants: an in vivo model

2019

Background To determine whether an experimental abutment mimicking the macro- and microstructure of a dental implant is a suitable method for recovering biofilm, and to describe the features of biofilms formed around such abutments on healthy implants. Material and Methods Experimental abutments were used in 15 patients without peri-implant diseases. After 14 days’ absence of dental hygiene in this area, the abutments were retrieved and analyzed through confocal laser scanning microscopy and scanning electron microscopy. The biofilm formation on the surface of the first 5 abutments was determined by a fluorescence-staining method using SYTO9 nucleic acid stain. In order to study the biofilm…

Impact on flavour release of the structure of composite gels containing polysaccharides: Example of the fruit préparations

2006

The main objective of this study was to understand the respective rôle of the structure of a food product and of the physicochemical interactions on flavour release. For that purpose, fruit préparations hâve been chosen as model matrices. Those matrices contain a polysaccharide as gelling agent, a cross-linked waxy corn starch (1.4%), a high sucrose content (35%), an acidic buffer and a strawberry aroma (17 molécules). Four matrices were developed by modifying either the composition or the concentration in gelling agent: two matrices of similar texture containing either LM pectin or carrageenan, and two carrageenan based matrices with différent gelled structures. In a first step; two comple…