16 research outputs found
Electromyography as an intraoperative test to assess the quality of nerve anastomosis – experimental study on rats
Many factors contribute to successful nerve reconstruction. The correct technique of anastomosis is one of the key elements that determine the final result of a surgery. The aim of this study is to examine how useful an electromyography (EMG) can be as an objective intraoperative anastomosis assessment method
The SS-OCT endomicroscopy probe based on MOEMS Mirau micro-interferometer for early stomach cancer detection
International audienceIn this paper, we present the construction and preliminary experimental results of a MOEMS fiber-based integrated probe for endoscopic optical imaging of stomach tissue using a Swept-Source Optical Coherence Tomography (SSOCT). The probe consists of a Mirau micro-interferometer, combined with a GRIN lens collimator and a micromirror scanner. We describe the building blocks of the probe, especially the monolithically integrated Mirau mirointerferometer, fabricated by wafer-level vertical stacking and anodic bonding of Si/glass components, and the electrothermal 2-axis MEMS microscanner allowing large swept angles (up to ±22°) at high frequencies (> kHz) for low driving voltages (<20 V). The results of probe characterization, performed in a designed SS-OCT system, have confirmed proper operation of the probe. The B-scan images were obtained for central wavelength of λc = 840 nm, swept range of Dλ = 60 nm and A-scan frequency of fA= 110 kHz. The axial resolution of the probe is equal to 5.2 μm (determined by applied swept source), whereas the lateral resolution, measured by use of USAF test pattern, is 9.8 μm
The SS-OCT endomicroscopy probe based on MOEMS Mirau micro-interferometer for early stomach cancer detection
International audienceIn this paper, we present the construction and preliminary experimental results of a MOEMS fiber-based integrated probe for endoscopic optical imaging of stomach tissue using a Swept-Source Optical Coherence Tomography (SSOCT). The probe consists of a Mirau micro-interferometer, combined with a GRIN lens collimator and a micromirror scanner. We describe the building blocks of the probe, especially the monolithically integrated Mirau mirointerferometer, fabricated by wafer-level vertical stacking and anodic bonding of Si/glass components, and the electrothermal 2-axis MEMS microscanner allowing large swept angles (up to ±22°) at high frequencies (> kHz) for low driving voltages (<20 V). The results of probe characterization, performed in a designed SS-OCT system, have confirmed proper operation of the probe. The B-scan images were obtained for central wavelength of λc = 840 nm, swept range of Dλ = 60 nm and A-scan frequency of fA= 110 kHz. The axial resolution of the probe is equal to 5.2 μm (determined by applied swept source), whereas the lateral resolution, measured by use of USAF test pattern, is 9.8 μm
Skin incision versusl aser – the influence of different techniques on scar formation and lymphatic drainage in rats. A preliminary report
Implementation of cone beam computed tomography, digital sculpting and three-dimensional printing in facial epithesis - a technical note
Prosthetic rehabilitation has hardly changed since the 1970s, and it is a time-consuming process that requires great skill and precision. This article presents the workflow related to the prosthetic reconstruction of patients with extensive maxillofacial defects using digital technologies such as cone beam computed tomography (CBCT), Zbrush software and three-dimensional (3D) printing. The use of CBCT captures a 3D image of a patient’s face in a few seconds, thus shortening the time to prepare an impression and increasing the patient’s comfort. Zbrush digital sculpting software enables one to quickly and efficiently design a prosthetic restoration. Printing a trial version for a try-on, as well as designing and printing pre-cast forms, improves workflow and eliminates the chances of an error. As shown in the example of a patient after a nasal resection, CBCT, digital sculpting, and 3D printing accelerate and improve the workflow of an anaplastologist when designing the epithesis. New technologies reduce costs and save time, while helping to overcome the technical obstacles that limit access to a facial prosthesis
Swept source optical coherence tomography endomicroscope based on vertically integrated Mirau micro interferometer: concept and technology
International audienceThis paper presents a concept of an endomicroscope for an early detection of neoplastic lesions in the human stomach tissue, based on the Swept Source Optical Coherence Tomography (SS-OCT) and an measurement probe with integrated Mirau micro interferometer. The system consists of pigtailed illumination and detection blocks, connected via a Gradient Index (GRIN) lens collimator to a MOEMS (Micro-Opto-Electro-Mechanical Systems) measurement probe (4 mm x 4 mm x 20 mm). The technology of Mirau micro interferometer is based on vertical multi-wafer bonding approach. The MOEMS probe is intended to be mounted on a continuum robot arm to perform in vivo microscopy of stomach tissues. First, the optical design of the SS-OCT endomicroscope is described, including an analysis of sensitivity. Then, we focus on the fabrication technologies and optical characterization of a key component of the Mirau micro interferometer, i.e. monolithically integrated focusing glass lens. SS-OCT endomicroscope will provide a fast axial scanning of tissues with A-scan sweep rate of 110 kHz, offering the axial resolution of 5.2 m and the lateral resolution of 10.2 m
In Vitro Human Skin Penetration, Antioxidant and Antimicrobial Activity of Ethanol-Water Extract of Fireweed (Epilobium angustifolium L.)
Epilobium angustifolium L. is applied as an antiseptic agent in the treatment of skin diseases. However, there is a lack of information on human skin penetration of active ingredients with antioxidative potential. It seems crucial because bacterial infections of skin and subcutaneous tissue are common and partly depend on oxidative stress. Therefore, we evaluated in vitro human skin penetration of fireweed ethanol-water extracts (FEEs) by determining antioxidant activity of these extracts before and after penetration study using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and Folin–Ciocalteu methods. Microbiological tests of extracts were done. The qualitative and quantitative evaluation was performed using gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC-UV) methods. The in vitro human skin penetration using the Franz diffusion chamber was assessed. The high antioxidant activity of FEEs was found. Gallic acid (GA), chlorogenic acid (ChA), 3,4-dihydroxybenzoic acid (3,4-DHB), 4-hydroxybenzoic acid (4-HB), and caffeic acid (CA) were identified in the extracts. The antibacterial activities were found against Serratia lutea, S. marcescens, Bacillus subtilis, B. pseudomycoides, and B. thuringiensis and next Enterococcus faecalis, E. faecium, Streptococcus pneumoniae, Pseudomonas aeruginosa, and P. fluorescens strains. In vitro penetration studies showed the penetration of some phenolic acids and their accumulation in the skin. Our results confirm the importance of skin penetration studies to guarantee the efficacy of formulations containing E. angustifolium extracts
In Vitro Human Skin Penetration, Antioxidant and Antimicrobial Activity of Ethanol-Water Extract of Fireweed (<i>Epilobium angustifolium</i> L.)
Epilobium angustifolium L. is applied as an antiseptic agent in the treatment of skin diseases. However, there is a lack of information on human skin penetration of active ingredients with antioxidative potential. It seems crucial because bacterial infections of skin and subcutaneous tissue are common and partly depend on oxidative stress. Therefore, we evaluated in vitro human skin penetration of fireweed ethanol-water extracts (FEEs) by determining antioxidant activity of these extracts before and after penetration study using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and Folin–Ciocalteu methods. Microbiological tests of extracts were done. The qualitative and quantitative evaluation was performed using gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography (HPLC-UV) methods. The in vitro human skin penetration using the Franz diffusion chamber was assessed. The high antioxidant activity of FEEs was found. Gallic acid (GA), chlorogenic acid (ChA), 3,4-dihydroxybenzoic acid (3,4-DHB), 4-hydroxybenzoic acid (4-HB), and caffeic acid (CA) were identified in the extracts. The antibacterial activities were found against Serratia lutea, S. marcescens, Bacillus subtilis, B. pseudomycoides, and B. thuringiensis and next Enterococcus faecalis, E. faecium, Streptococcus pneumoniae, Pseudomonas aeruginosa, and P. fluorescens strains. In vitro penetration studies showed the penetration of some phenolic acids and their accumulation in the skin. Our results confirm the importance of skin penetration studies to guarantee the efficacy of formulations containing E. angustifolium extracts
COMPARISON OF ARTIFICIAL HYDROPHILIC AND LIPOPHILIC MEMBRANES AND HUMAN SKIN TO EVALUATE NIACINAMIDE PENETRATION IN VITRO
The evaluation of skin penetration of active substances from topical preparations is a pre-clinical requirement in the pharmaceutical industry. While in vitro preparations of human or animal skin are frequently used the development of artificial lipophilic and hydrophilic membranes with similar properties to human or animal skin need to be developed. This preliminary study compared the in vitro permeation of niacinamide (vitamin B3), which is used as a model drug, across artificial hydrophilic and lipophilic membranes with iv vitro penetration across human skin. The experiments were carried out in Franz diffusion cells. Artificial membranes were filter paper impregnated with either collodium (hydrophilic), stearic acid, cetyl alcohol or cetyl alcohol + cholesterol (lipophilic). Acidic and neutral hydrogel and emulsion (pH 5.4 and 7.4) containing 0.5% of niacinamide were applied to membranes for up to 4 hours. Niacinamide permeated hydrophilic better than lipophilic membranes. There were no significant differences between the cumulated amounts of niacinamide that penetrated artificial lipophilic membranes consisting of, stearic acid, cetyl alcohol and cholesterol as compared with human skin in vitro. Also, hydrogel and emulsion solvents gave similar results. In conclusion, these artificial membranes seem to be a promising alternative to human or animal skin
Vitamin D Status in Patients before Thyroidectomy
Thyroid neoplasms (tumors) are the most common pathology of the endocrine system that requires surgery, and in most cases changes are benign. The surgical treatment of thyroid neoplasms consists in total, subtotal, or one lobe excision. Our study aimed to assess the concentration of vitamin D and its metabolites in patients before thyroidectomy. The study included 167 patients with thyroid pathology. Before the thyroidectomy procedure calcidiol (25-OHD), calcitriol (1,25-(OH)2D), and vitamin D binding protein (VDBP), as well as basic biochemical parameters, were measured using an enzyme-linked immunosorbent assay kit. Data analysis showed that the cohort of patients has a significant 25-OHD deficiency and proper concentration of 1,25-(OH)2D. Before the surgery, more than 80% of patients have extreme vitamin D deficiency (<10 ng/mL), and only 4% of the study group has proper 25-OHD concentration. Patients undergoing thyroidectomy are exposed to many complications, including calcium reduction. Our research has shown that patients prior to surgery have a marked vitamin D deficiency, an indicator that may affect their subsequent convalescence and prognosis. The results suggest that determination of vitamin D levels prior to thyroidectomy may be useful for potential consideration of supplementation when vitamin D deficiency is marked and needs to be incorporated into the good clinical management of these patients