Comparison of two picosecond lasers to a nanosecond laser for treating tattoos: a prospective randomized study on 49 patients.

BACKGROUND: Q-switched nanosecond lasers demonstrated their efficacy in treating most types of tattoos, but complete disappearance is not always achieved even after performing numerous laser sessions. Picosecond lasers are supposed to be more efficient in clearing tattoos than nanosecond lasers, but prospective comparative data remain limited. OBJECTIVE: To compare on different types of tattoos the efficacy of a nanosecond laser with two types of picosecond lasers. METHODS: We conducted a prospective randomized study performed from December 2014 to June 2016 on adult patients with all types of tattoos. The tattoos were divided into two halves of equal size. After randomization, half of the tattoo was treated with a picosecond laser and the other half with a nanosecond laser. The evaluation was performed on standardized pictures performed before treatment and 2 months after the last session, by two physicians, not involved in the treatment, blinded on the type of treatments received. The main end point was a clearance above 75% of the tattoos. RESULTS: A total of 49 patients were included. Professional tattoos represented 85.7%, permanent make-up 8.2% and non-professional tattoo 6.1%. The majority were black or blue and 10.2% were polychromatic. No patient was lost during follow-up. A reduction of 75% or more of the colour intensity was obtained for 33% of the tattoos treated with the picosecond lasers compared to 14% with the nanosecond laser (P = 0.008). An improvement superior to 75% was obtained in 34% monochromic black or blue tattoos with the picosecond lasers compared to 9% for the nanosecond laser. Only one of the five polychromic tattoos achieved more than 75% of improvement with the two types of laser. CONCLUSION: Our results show a statistically significant superiority of the picosecond lasers compared to the nanosecond laser for tattoo clearance. However, they do not show better efficacy for polychromic tattoos and the difference in terms of side-effects was also minimal with a tendency of picosecond lasers to be less painful.

Laser hair removal after surgery vs. surgery alone for the treatment of pilonidal cysts: a retrospective case-control study.

BACKGROUND: Based on the presumed role of hair in pilonidal cyst (PNC) pathogenesis, laser epilation has been used to decrease recurrences. However, most of the data rely on case reports and uncontrolled series, and the rare controlled studies reported conflicting results. The objective of this study was to investigate the efficacy of laser hair removal (LHR) to decrease the recurrence rate after surgery of PNC vs. surgery alone. METHODS: We conducted a retrospective monocentric case-control study in the departments of Pediatric Surgery and Laser Center of Dermatology of the University Hospital of Nice in France from January 2010 to June 2017. We included all patients with PNC who had surgery during the period, and we compared patients who had LHR after surgery to those having surgery alone. The main outcome was the prevalence and number of recurrences of PNC in each group. RESULTS: Twelve patients - eight treated with alexandrite laser and four patients with Nd : YAG - were included in the cases group; 29 patients treated with surgery alone were included in the control group. The mean and the median number of laser sessions were 4.2 and 5, respectively (extremes 1-10). The postsurgical recurrence rate without LHR was 51.7%, and their number varied from 1 to 3. A significant decrease in the recurrence rate was observed after LHR (8.3%) compared to control group (P < 0.001). The median duration before recurrence was 14 months for surgery alone. The median follow-up was 18 months (1-30 months) for LHR group and 30 months (6-72 months) for surgery alone group. Two patients had abnormal healing or persistent sinus after surgery alone compared to none in the group who undergone laser procedure after surgery. CONCLUSIONS: Laser hair removal decreases the risk of delayed healing and of recurrences of PNL after surgical procedure.

Feeding value of whole raw soya beans as a protein supplement for beef cattle consuming low-quality forages.

Experiments (Exp) I and II were conducted to compare raw whole soya beans (WSB), roasted (rWSB) or other protein sources as supplements of low-quality forages fed ad libitum to beef cattle, upon DM intake (DMI), ruminal and blood parameters, and animal performance. Exp I: treatments for wheat straw fed to four ruminally cannulated steers were (i) Control-WS: no supplement; (ii) WSB-WS: whole soya beans; (iii) rWSB-WS: roasted WSB; and (iv) SBM-WS: soybean meal-wheat midds mixture; all fed at 1.4 kg DM/day. Exp II: 12 steers grazed deferred grain sorghum (DS) receiving these treatments: (i) Control-DS: no supplement; (ii) WSB-DS: 1.26 kg DM/day whole soya beans; and (iii) SFM-DS: 1.35 kg DM/day of sunflower meal. In Exp I, WS DMI resulted 47, 52 and 41% greater for WSB-WS, rWSB-WS and SBM-WS, respectively, than Control-WS (p < .05). In Exp II, the DMI of DS was unaffected by supplementation; a substitution of DS by supplement was found for WSB-DS (p < .05); however, total diet and digestible DMI increased with supplementation (p < .05). Rumen pH in Exp I remained unaffected by supplementation, but N-NH3 as well as blood urea-N in Exp II increased (p < .05). In Exp II, average daily weight gains improved similarly with both supplements compared with Control-DS. Additionally, feed-to-gain ratio decreased (p < .05), being lower for WSB-DS (8.3) vs. SFM-DS (9.9). Roasting effects of WSB as a supplement for low-quality forages were not detected, and all protein sources increased total diet DMI and forage utilization. Only moderate cattle weight gains could be expected for unsupplemented DS.

Complete nonlinear polarization control in an optical fiber system.

We consider the counterpropagating interaction of a signal and a pump beam in an isotropic optical fiber. On the basis of recently developed mathematical techniques, we show that an arbitrary state of polarization of the signal beam can be converted into any other desired state of polarization. On the other hand, an unpolarized signal beam may be repolarized into two specific states of polarization, without loss of energy. Both processes of repolarization and polarization conversion may be controlled by adjusting the polarization state of the backward pump.

[Resistant acquired bullous epidermolysis with severe ocular involvement: the success of extracorporeal photochemotherapy]. / Epidermolyse bulleuse acquise résistante avec atteinte oculaire sévère: succès de la photochimiothérapie extracorporelle.

BACKGROUND: Epidermolysis bullosa aquisista can leave several functional sequelae. The lesions sometimes resist treatment. CASE REPORT: We report a case of a 25-year-old young man presenting with a severe epidermolysis bullosa acquisita confirmed by the electronic immunomicroscopy. He had a major ocular involvement with symblepharon and cicatricial synechial lesions. He was almost blind because of corneal scars. All immunosuppressive treatments had failed: systemic corticoids, cyclosporin, azathioprine. The introduction of extracorporeal photochemotherapy resulted in the healing of the lesions, after a total of 32 procedures. All treatment are now stopped, and the lesions are purely cicatricial, without any relapse of the disease since 9 months. Corneal grafts are now under process, to try to recover a part of the lost visual acuity. DISCUSSION: This case demonstrates the efficacy of extracorporeal chemotherapy to be tried in case other treatments failed.

Singular tori as attractors of four-wave-interaction systems.

We study the spatiotemporal dynamics of the Hamiltonian four-wave interaction in its counterpropagating configuration. The numerical simulations reveal that, under rather general conditions, the four-wave system exhibits a relaxation process toward a stationary state. Considering the Hamiltonian system associated to the stationary state, we provide a global geometrical view of all the stationary solutions of the system. The analysis reveals that the stationary state converges exponentially toward a pinched torus of the Hamiltonian system in the limit of an infinite nonlinear medium. The singular torus thus plays the role of an attractor for the spatiotemporal wave system. The topological properties of the singular torus confer a robust character to the stationary solution when the boundary conditions or the length of the nonlinear medium are modified. Furthermore, an adiabatic approach of the boundary conditions reveals that singular tori also play a major role for the description of the spatiotemporal dynamics of the wave system.

Role of singular tori in the dynamics of spatiotemporal nonlinear wave systems.

We show that the peculiar topological properties inherent to singular tori play a major role in the spatiotemporal dynamics of counterpropagating nonlinear waves. Under rather general conditions, these Hamiltonian wave systems exhibit a relaxation process towards a stationary state. We show that this stationary state converges exponentially towards the singular torus of the associated Liouville-integrable Hamiltonian system in the limit of an infinite medium. The singular torus then appears as an attractor for the infinite dimensional dynamical system, a feature which is illustrated by several key models of spatiotemporal wave interactions.

A peculiar form of amicrobial pustulosis of the folds associated with systemic lupus erythematosus and other auto-immune diseases.

Amicrobial pustulosis of the folds is a new entity which was initially described in association with systemic lupus erythematosus (SLE). We report four cases of this rare pustulosis occurring in the course of various auto-immune disorders. Dermatological features were similar in all patients. The primary lesions were small pustules which coalesced and formed erosive areas underlined with pustular lesions. They were localized in the folds. Three of the four patients had also isolated pustules on the scalp. Spongiform pustules were histologically present. A primary bacterial or fungal infection was ruled out by cultures on appropriate media. Serum calcium level was normal. Associated auto-immune diseases were: systemic lupus erythematosus, incomplete systemic lupus erythematosus, 'idiopathic' thrombocytopenic purpura and myasthenia gravis without thymoma (one of each). The relationship between this peculiar form of pustulosis and autoimmunity remains to be elucidated. The pustulosis did not respond to antibiotics but disappeared with systemic or topical corticosteroids.

Analogs of Substance P modified at the C-terminus which are both agonist and antagonist of the NK-1 receptor depending on the second messenger pathway.

The initial goal of this study was to analyze, using photolabeling, the interactions between Substance P and its tachykinin NK-1 receptor. Therefore, the photoreactive amino acid para-benzoyl-phenylalanine (pBzl)Phe was incorporated into the Substance P sequence from position 4 to 11 leading to Bapa0[(pBzl)Phex]SP analogs. Biotinyl sulfone-5-aminopentanoic acid (Bapa) was introduced in order to purify the covalent complex. These photoreactive SP analogs were first assayed for their affinity for the two binding sites associated with the NK-1 receptor, as well as for their potency in activating the phospholipase C and adenylate cyclase pathways. All analogs photoreactive from position 4 to 11 have moderate to high affinity for the two NK-1 receptor-binding sites, except for the analog modified at position 7. This affinity could be correlated to their potency to activate the phospholipase C and adenylate cyclase pathways, except for the analog photoreactive at position 11. Bapa0[(pBzl)Phe11]SP was found to be an agonist in the phospholipase C pathway and an antagonist in the adenylate cyclase pathway, other analogs modified at position 11 were therefore analyzed. Among these, Bapa0[Pro9, (pBzl)Hcy(O2)11]SP is a partial agonist, whereas Bapa0[Hcy(ethylaminodansyl)11]SP is a full agonist in the phospholipase C pathway, the two analogs being antagonist in the adenylate cyclase pathway. These results show that analogs of SP can be simultaneously agonist at one binding site and antagonist at the other binding site associated with the NK-1 receptor.