[Fluorescent imaging in digestive endoscopy].
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to Serge Mordon.
Explore the source record for details and available documents.
BACKGROUND AND OBJECTIVES: Laser irradiation induces blood coagulation by heating of blood components. It is a complex phenomenon which encompasses a variety of processes, such as cell shape modification, cell membrane rupture, protein denaturation, aggregation, and finally blood gelation. An in vitro study was performed to investigate heating temperatures leading to transformation of blood and to have a better understanding of the dynamics of temperature dependent modifications of blood in the near-infrared. STUDY DESIGN/MATERIALS AND METHODS: Slow heating of whole blood and hemolized blood was performed using a specific optical chamber. Eight hundred and five and 940 nm light transmission of blood was measured as a function of time during heating at various temperatures (60-75 degrees C). RESULTS: During heating of whole blood, three phases were clearly identified. For hemolized blood, only phase 3 was present. For whole blood, the duration of each phase was correlated to blood temperature. A temporary increase of transmission was observed during heating with a maximum at 65 degrees C. The analysis of the dynamics of temperature dependent modifications of blood are consistent with cell shape modification, denaturation, and aggregation of blood, resulting in the formation of an aqueous gel-matrix. CONCLUSIONS: "Slow" vessel heating which is now proposed as the optimal mechanism for permanent vessel closure should be reconsidered in terms of our results. In that particular case, the optical coefficients of blood could be different from those expected. In case of a large blood vessel, this could be an advantage since a "temporary" higher transmission of light could lead to a more homogeneous heating of the blood vessel. In case of a small blood vessel, this phenomenon could lead to a collateral damage of the skin.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
BACKGROUND: Nonablative remodeling has recently been proposed as a new antiaging treatment with no downtime. This technique could greatly benefit the increasing numbers of patients who are looking for new and efficient techniques, with a minimum of discomfort. MATERIALS: AND METHODS. The 1.54 microm wavelength has been proposed for this application because this wavelength is well absorbed by water yet virtually not at all by melanin, allowing deep penetration into the skin. To protect the epidermis during laser irradiation, a cooling system (+5 degrees C) uses a sapphire window (purified tetrafluoroethane circulates in a pipe around the sapphire) directly applied to the skin through which the laser pulse may be fired. RESULTS: Several clinical trials have been published and have demonstrated that clinical improvement was correlated with data from ultrasound imaging, histology, and profilometry. A recent trial on the forehead and neck yielded additional data on elasticity measured by echorheometry. CONCLUSIONS: The 1.54 microm laser is safe and effective for remodeling in all of these published studies. Remodeling requires months to achieve its goal, and the kind of improvement that can be expected should be explained to the patient. Long-term follow-up showed that the improvement increased after each treatment and lasted for months after the final session.
OBJECTIVES: The aim of this study was to test whether peroxynitrite neutralizers would reduce peroxynitrite accumulation and improve myocardial contractile dysfunction and inflammation in endotoxin-treated rats. BACKGROUND: Release of endogenous proinflammatory cytokines such as tumor necrosis factor (TNF)-alpha in response to endotoxin is responsible for the production of large amounts of nitric oxide (NO), which may exert detrimental effects on the myocardium in animal models, isolated hearts, and isolated cardiac myocytes. Recent studies have indicated that many of the deleterious effects of NO are mediated by peroxynitrite, a powerful oxidant generated from a fast diffusion-limited reaction of NO and superoxide anion. METHODS: We studied the effects of peroxynitrite neutralizers, such as mercaptoethylguanidine (MEG) sodium succinate (10 mg/kg) and 5,10,15,20-tetrakis(4-sulfonatophenyl)-porphyrinato iron (III) (FeTPPS) (30 mg/kg) on peroxynitrite accumulation, in vivo endothelial cell-leukocyte activation on the mesenteric venule, and myocardial contractile dysfunction and inflammation in a model of sepsis induced by injection of endotoxin (10 mg/kg) in rats. RESULTS: Mercaptoethylguanidine sodium succinate and FeTPPS largely prevented the accumulation of peroxynitrite as measured by plasma rhodamine fluorescence and heart nitrotyrosine staining. Interestingly, MEG sodium succinate and FeTPPS improved endotoxin-induced myocardial contractile dysfunction, which was associated with reduced degradation of nuclear factor kappa B inhibitory protein I-kappa-B, plasma TNF-alpha levels, and microvascular endothelial cell-leukocyte activation. CONCLUSIONS: These observations suggest that the beneficial effects of MEG and FeTPPS on endotoxin-induced myocardial contractile dysfunction could be related to the unique effects of these compounds on cardiovascular inflammation processes.
BACKGROUND AND OBJECTIVES: Millisecond pulsed 1,064 nm Nd:YAG lasers have been developed for the treatment of leg telangiectasias. To date there have been very few side by side comparison studies of laser versus the gold standard sclerotherapy in treating small leg veins. This study aims to compare a long pulsed Nd:YAG laser with contact cooling to sclerotherapy for treating small diameter leg telangiectasias by evaluating objective and subjective clinical effects. STUDY DESIGN/PATIENTS AND METHODS: Fourteen patients were selected with leg telangiectasias ranging from 0.5 to 2 mm at four comparable sites. One site was treated with long pulsed Nd:YAG alone, the second received sclerotherapy alone, the third laser then sclerotherapy, and the last one sclerotherapy then laser. The patients were followed up at 3 months after the last treatment. Photographs were taken pre-operatively and at 3 months after the last session. They were used for objective and comparative analysis. Statistical analysis was performed using Friedman's test controlling for subject. RESULTS: Improvement was tabulated from the photographic assessment on an improvement scale from 0 (no change) to 4 (greater than 75% clearing). There were clinical improvements in the laser group than sclerotherapy without statistical significance. Side effects were minimal and included hyperpigmentation. CONCLUSIONS: This pilot study demonstrates that the Smartepil LS long pulse Nd:YAG 1,064 nm laser can yield results similar to sclerotherapy in the treatment of small leg telangiectasias. Combination of both methods could increase response to treatment.
BACKGROUND AND OBJECTIVES: The potential applications for facial laser cartilage reshaping (LCR) have generated increasing clinical interest. This study aimed to evaluate in vivo LCR of the rabbit ear using a 1.54 micro m Er:Glass laser in combination with contact cooling. STUDY DESIGN/MATERIALS AND METHODS: LCR was performed in vivo on 12 rabbit ears using a 1.54 micro m Er:Glass laser (Aramis, Quantel Medical, Clermont Ferrand, France) connected to a 4 mm chilled (+5 degrees C) handpiece placed in contact to the skin. Ear curvature was predetermined using a perforated cylindrical guide also used to standardize laser beam delivery. The treatment consisted of 15 spots (3 millisecond, 7 pulses, 12 J/cm(2), 2 Hz, 84/cm(2) cumulative fluence) applied on 10 contiguous parallel rows along the ear. After irradiation, the aluminum jig was replaced by a holder (10 mm diameter plastic tube) maintaining the curvature. This holder was secured with sutures and covered by an adhesive gauze bandage dressing to keep new form during 7 days. In order to assess thermal damage, biopsies were taken on irradiated areas and 1 week, 3 weeks and 6 weeks and studied using haematoxylin-erythrosin-safran (HES) and orcein staining and PCNA to detect cells in cycle. RESULTS: Using the laser with the parameters given above, no immediate visible effects were observed on the skin (no swelling, no bleaching). There were also no late visible side effects like crusting, or blistering. The laser treatment produced changes in the shape of every ear after the dressing was removed. A slight tendency to recover its initial shape was observed for each ear. However, the curvature was stabilized after 10 days and the average shape retention was 64+/-4% at 6 weeks, with a curvature radius of 7.25+/-0.75 mm, instead of 5 mm initially. Histological examination of the laser irradiated side at 1 week showed an intact epidermis. A reduced inflammation process was seen in the dermis. A modification of half of the layer of cartilage was observed at the opposite side where the laser irradiation was applied and proliferative cells were detected inside. At 3 weeks, an important chondroblastic proliferation was observed around the area of contracted cartilage. At 6 weeks, significant thickening of the cartilage layer was observed (from 300 to 490 micro m) and new chondrocytes were clearly seen. CONCLUSIONS: Rabbit ear cartilage can be reshaped with an Er:Glass laser. This technique could offer exciting possibilities that may help patients whose cartilage-lined joints have been affected by disease or trauma. This technique could be certainly utilized to correct alar cartilage deformities and septum deviation of cleft lips.
BACKGROUND: Retinaldehyde has been proven to be effective in the reduction of facial wrinkles. It has also demonstrated its usefulness when used before and after laser skin resurfacing. OBJECTIVE: A monocentric, comparative, randomized, double-blind study was performed to evaluate the efficacy of retinaldehyde versus excipient in combination with non-ablative laser remodeling treatment. METHODS: A total of 16 female patients (mean age 45 years) were enrolled for neck line and forehead rhytid treatment. They were randomly assigned into two groups. The RAL group (eight patients) was treated with a non-ablative laser (1540 nm Er:glass, 10 J/cm2 per pulse, three pulses, 2 Hz repetition rate, 4 mm spot, +5 degrees C cooling) and daily topical application of 0.05% retinaldehyde immediately after the first laser treatment and up to 3 months after the fifth treatment. The CTRL group (eight patients) was treated under similar conditions, except with a daily application of excipient. The thickness of the skin (forehead and neck) was measured by ultrasound imaging before the first treatment, 1 month after the third treatment, 1 month after the fifth treatment and 3 months after the fifth treatment. RESULTS: An increase of dermal thickness was observed for all patients treated by laser (groups RAL and CTRL) on the forehead and neck. However, the increase was greater for the RAL group (retinaldehyde) when compared with the CTRL group (excipient). Three months after the fifth treatment, the increase in dermal thickness (%) was, respectively, 5.27 versus 1.13 for the forehead and 10.54 versus 3.57 for the neck. The difference between groups was statistically significant in favor of the retinaldehyde group for the forehead (p<0.05) and of limited significance for the neck (p=0.08). CONCLUSION: When considering the reduced number of patients in each group, the statistical analysis demonstrates an evident advantage of using retinaldehyde versus excipient. This study demonstrates that irradiation with a 1540 nm Er:glass laser can be potentiated with concomitant daily topical application of 0.05% retinaldehyde.
BACKGROUND/OBJECTIVE: As remodeling is getting more popular with patients, long-term studies are becoming necessary. The aim of this 35-month clinical study was to evaluate the long-term benefits obtained using a 1540-nm Er:glass laser for non-ablative remodeling of perioral and periorbital rhytids. The role of maintenance treatments was also investigated. STUDY DESIGN/METHODS: Eleven women with periorbital and perioral rhytids underwent a series of five treatments at 6-week intervals with an Er:glass laser. Five patients subsequently received two maintenance retreatments and six did not. The maintenance treatments were performed at 14 and 20 months. Silicone imprints were performed to measure anisotropy before treatment, at 6 months, at 14 months and at 35 months. Patient self-evaluation/questionnaire was also done to assess adverse effects and subjective clinical improvement. RESULTS: For all 11 patients, the percentage of anisotropy reduction was 41.21% at 6 months, 51.76% at 14 months and 29.87% at 35 months. No adverse effects were noted. Patient satisfaction was high at the end of the evaluation. Retreated patients were more satisfied than non-retreated ones. However, there was no difference in the anisotropy factor between the two groups. CONCLUSION: Treatment of facial rhytids with a non-ablative 1540-nm Er:glass laser system can produce benefits that persist over 2 years after the last treatment.
BACKGROUND: Intense pulsed light (IPL) sources have been reported in non-ablative photorejuvenation, but the excellent histological findings do not always coincide with the clinical results and patient satisfaction index (SI). METHODS: Ten female patients (two forehead, four periocular and four perioral), ages ranging from 28 to 46 years, skin types II-IV, wrinkle types I-III, participated in the study. The IPL system was applied with the yellow (570 nm) cut-off filter, 30 J/cm(2), single pulse, followed by the Nd:YAG at 120 J/cm(2), double pulse (7 ms per shot with 20 ms between pulses) on the wrinkled areas only. Three sessions were given at monthly intervals, and an assessment was made 1 and 6 months after the third session. Biopsies were taken from four consenting patients as a cross-section before the first treatment and then 1 and 6 months after the third session. For clinical control and contrast of tissue results, a group of 10 patients (two forehead, four periocular and four perioral; ages ranging from 27 to 47 years, skin types II-IV, wrinkle types I-III) was treated only with IPL, using the same parameters and sessions. Histologies were taken from four consenting patients. RESULTS: The histology showed thickening of the epidermis with good dermal collagen organization in both groups. However, the combined treatment showed more dramatic changes in histological tissue condition, and ectatic blood vessels were seen in the deeper dermis. The patient SI values, related to the results, were lower when IPL was used alone. All patients completed the study. In the combined treatment group, overall SIs of 8 (80%) and 8 (80%) were obtained at the control points of 1 and 6 months, respectively, after session 3, compared with SIs of 6 (60%) and 4 (40%) scored by patients in the IPL group at the same points. Discomfort and side effects were minimal in both groups. CONCLUSIONS: The addition of the Nd:YAG laser to the IPL regimen in non-ablative skin rejuvenation gave very good histological results, which were echoed by stronger patient satisfaction than in the control group treated only with IPL. Visible improvement in the skin condition of both groups was achieved, but was better in the combined treatment group.
Excessive activation of calpains has been implicated in the pathophysiology of inflammation, trauma, and ischemia reperfusion injury. Here, we investigated the effects of calpain inhibition on myocardial dysfunction and inflammation induced by endotoxin in rats. Rats were treated i.v. with endotoxin (10 mg/kg) or endotoxin plus calpain inhibitors and were then prepared after 4 h for myocardial contractility assessment, detection of endothelium leukocyte interactions, and plasma TNF-alpha, nitrite/nitrate, and endocan levels. Compared with vehicle-treated rats, hearts from endotoxin-treated rats had reduced systolic performance that was partially prevented by calpain inhibitors, i.e., acetyl-leucyl-leucyl-arginal (leupeptin), carbobenzoxy-valyl-phenylalanial (calpain inhibitor III), and N-acetyl-leucinyl-leucinyl-norleucinal (ALLN). Leupeptin and calpain inhibitor III reduced plasma TNF-alpha levels in endotoxin-treated rats. ALLN reduced plasma TNF-alpha and nitrite/nitrate levels in endotoxin-treated rats. Endotoxin treatment increased mesenteric venule leukocyte rolling (10 +/- 3 leukocytes/min vs. 44 +/- 10 leukocytes/min; P < 0.01) and adhesion (2 +/- 2 leukocytes/min vs. 15 +/- 3 leukocytes/min; P < 0.01), which was reduced by calpain inhibitors. Attenuation of leukocyte endothelium interactions observed in calpain inhibitor-treated rats with sepsis was associated with increases in plasma anti-adhesion molecule endocan. In conclusion, calpain inhibitors improved endotoxin-induced cardiac dysfunction, which may be attributed to the modulation of endothelium leukocyte interactions in the inflamed vasculature.
OBJECTIVE: To determine whether sphingomyelinase pathway activation would participate in myocardial depression induced by endotoxin. DESIGN: Randomized, controlled trial. SETTING: Experimental laboratory. SUBJECTS: Male Sprague-Dawley rats, isolated rat heart, and cardiac myocytes. INTERVENTIONS: Cardiovascular function was evaluated in rats injected with saline, endotoxin (10 mg/kg, intravenously), and N-oleoylethanolamine (NOE; 10 mg/kg, intravenously). In ex vivo experiments, isolated rat hearts were perfused with endotoxin (5 microg/mL). For pharmacologic intervention, NOE (1 micromol/L) was admixed to the perfusate 20 mins before endotoxin. In in vitro experiments, ventricular myocytes were incubated with sphingosine (20 microM). Myocyte cell shortening and calcium transient were measured. Mitochondrial membrane potential was measured using the cationic dye tetramethylrhodamine methylester fluorescence technique. MEASUREMENTS AND MAIN RESULTS: Endotoxin treatment at 4 hrs did not alter mean arterial pressure and abdominal blood flow compared with control rats. Left ventricle developed pressure (LVDP) and its first derivatives (i.e., maximal and minimal change in pressure over time [dP/dtmax and dP/dtmin]) were decreased after 4 hrs in endotoxin-treated rats compared with control rats. NOE (10 mg/kg) treatment largely prevented left ventricular systolic function alterations of endotoxin-treated hearts (n = 6 in each group). In isolated rat heart, endotoxin (5 microg/mL) caused increases in tumor necrosis factor-alpha perfusate concentration and delayed depression of LVDP, dP/dtmax, and dP/dtmin after 60 mins, which was partially abrogated in the presence of the ceramidase inhibitor NOE (1 micromol/L). Sphingosine (20 microM) caused decreases in cell fractional shortening, calcium transient, and mitochondrial membrane potential of cardiac myocytes. CONCLUSION: These observations suggest that the sphingomyelinase pathway participates in endotoxin-induced myocardial depression.
BACKGROUND: Nonablative remodeling has been recently proposed as a new, no-down-time, anti-aging treatment. Objective. The objective was to evaluate the efficacy and safety of nonablative skin remodeling with a 1540-nm Er:Glass laser on neck lines and forehead rhytids. METHODS: Twenty female patients (mean age 45 years) were enrolled. Skin thickness and mechanical properties were measured before the first treatment, 1 month after the third treatment, 1 month after the fifth treatment, and 3 months after the fifth treatment. RESULTS: All patients reported an improvement in both skin tone and texture. Using ultrasound imaging, dermal thickness of neck and forehead increased, respectively, by 70+/-13 microm (p<0.001) and 110+/-19 microm (p<0.003). A dramatic increase of initial stress of the forehead skin (firmness) was obtained, from 7.62+/-3.68 before treatment to 16.68+/-7.44 3 months after the fifth treatment (p<0.0002). No immediate or late adverse effects were noted throughout the treatment regimen. CONCLUSION: This study demonstrates that irradiation with a 1540-nm Er:Glass laser emitting in a pulsed mode and coupled with an efficient contact cooling system increases dermal thickness and firmness, leading to a clinical improvement of neck lines and forehead rhydits.
A rapid, continuous method for noninvasively monitoring the effectiveness of several antibacterial agents in real time by using a model of wound infection was developed. This study was divided into three steps: (i) construction of a plasmid to transform Escherichia coli into a bioluminescent variant, (ii) study of the bioluminescent E. coli in vitro as a function of temperature and pH, and (iii) determination of the MIC and the minimal bactericidal concentration of sulfamethoxazole-trimethoprim (SMX-TMP). Finally, the efficacy of SMX-TMP was monitored in vivo in a cutaneous wound model (hairless rat) infected with this bioluminescent bacterium by using a bioluminescence imaging system. E. coli was transformed by electroporation with a shuttle vector (pRB474) containing the firefly (Photinus pyralis) luciferase gene, resulting in a bioluminescent phenotype. It was found that pH 5.0 was optimal for incorporation of the susbstrate D-luciferin for the luciferase reaction. In vitro, when the agar dilution method, standard turbidity assays, and the bioluminescence imaging system were used, E. coli(pRB474) proved to be susceptible to SMX-TMP. In vivo, at 4 h, SMX-TMP treatment was already efficient compared to no treatment (P = 0.034). At 48 h, no bioluminescence was detected in the wound, demonstrating the susceptibility of E. coli to SMX-TMP. In conclusion, this study points out the advantage of using bioluminescence imaging to evaluate the effects of antibiotics for the treatment of acute infections in vivo in a nondestructive and noninvasive manner.
BACKGROUND AND OBJECTIVES: Evaluation of the efficacy, on 1-2 mm blue leg telangiectasia, of a 1,064 nm Nd:YAG laser emitting in a non uniform pulse sequence calculated to consider Met-Hb formation during laser irradiation of a blood vessel. MATERIALS AND METHODS: A 1,064 nm Nd:YAG laser (Quantel Medical, Athos, France) was used in a non uniform pulse sequence mode, fluences: 300-360 J/cm(2) spot: 2 mm, + 5 degrees C contact cooling. The clinical evaluation was performed on 11 female patients, average age: 43 (25-57) years, phototype I-VI. All subjects were previously examined with Doppler ultrasound. A treatment site (6 x 4 cm) was selected on each patient. The topography of the vessels network was reported on a tracing plastic frame before each session and 6 weeks after the last one. These frames were digitized and the number of vessels was determined using the Digitized Tracing Frames Technique. Side effects were noted before and after every treatment, and 6 weeks after the last one. This study lasted for 10 months. RESULTS AND DISCUSSIONS: Patients tolerated the procedure without anesthesia. Moderate pain, transient erythema and edema, one hyperpigmentation and one matting were noted. There was no hypopigmentation. 55% (P < 0.002) vessels clearance after one session, 86% after two sessions (P < 0.001), and 98% (P < 0.001) after three sessions were obtained. On two patients, the treatment was completed after two sessions with a full clearance. Data reported in this study were obtained thanks to a computerized calculation of vessels clearance. They are similar or superior to those reported in the literature about 1,064 nm Nd:YAG lasers and leg telangiectasia. CONCLUSIONS: Since, it was developed to consider the modification of blood absorption and the methemoglobin formation which leads to an increase of the 1.06 microm wavelength absorption, the non uniform pulse mode emphasizes the efficacy of this 1,064 nm Nd:YAG laser concerning the treatment of blue leg veins telangiectasia between 1 and 2 mm. This mode gives the possibility to deliver high energy while preserving the surrounding tissue and leads to a rapid vessel clearance with reduced pain and few side effects when compared to previously published clinical studies using a 1.06 microm laser.
BACKGROUND AND OBJECTIVES: To assess a choroidal heat shock protein hyperexpression after transpupillary thermotherapy (TTT) performed with exposures shorter than 60 seconds. STUDY DESIGN/MATERIALS AND METHODS: Nine male pigmented rabbits were anesthetized and TTT was performed on their right eye with a 810 nm diode laser (Iridis, Quantel-Medical (France)) (spot size: 1.3 mm). Three exposure durations (60, 30, or 15 seconds) were used with three ranges of power for each duration ("high," "mild," or "low"). A series of laser impacts was delivered to the posterior pole of the retina. Left eyes were used as controls. Twenty-four hours after laser irradiation, the animals were killed and histological study was performed on chorioretinal layers. Tissue samples were fixed in formalin and embedded in paraffin. A monoclonal antibody was used to detect Hsp70 immunoreactivity (mouse IgGl, SPA-810, Stress Gen, Victoria, BC, Canada), followed by a biotinylated goat anti-mouse antibody (Dako, Glostrup, Denmark), revealed by the avidin-biotin complex (Vectastain kit, Vector Laboratries, Burlingame, CA, USA) and the AEC chromogen. Retinal structures were further identified by HES coloration. RESULTS: During the experiments, the laser spots were not visible except for the strongest "high" powers for each exposure duration, where a whitening was discernable at the end of the laser exposures. A strong HSP70 immunoreactivity was detected in choroidal, non-pigmented cells for laser exposures lasting 60, 30, or 15 seconds with "mild" laser powers. On the contrary, rare HSP hyperexpression was detected with "high" or "low" laser powers lasting 60, 30, or 15 seconds. No HSP-70 immunoreactivity was detected on control eyes nor outside of the irradiated zones of treated eyes. CONCLUSIONS: Transpupillary laser irradiation lasting 15, 30, or 60 seconds induces an hyperexpression of HSP on choroidal layers. This could be a basis for the use of TTT with "short" laser exposures.