SynopsisSince ancient times, human beings have been trying to protect their skin against the adverse effects of the sun. From the first mineral sunscreens used by Egyptians, to the current more sophisticated ultraviolet (UVA/UVB) organic sunscreens, progress has been made in terms of sun protection and deeper knowledge of skin physiology has been acquired in the process. The solar spectrum is composed of radiations of various wavelengths having specific, as well as overlapping effects on skin. UVB is mainly responsible for sunburn and DNA dimer formation that can lead to mutation. UVA generates oxidative reactions affecting DNA, proteins and lipids, and is also immunosuppressive. Recently, visible light and infrared radiation (IR) have been associated with oxidative damage and IR has been additionally linked to adverse heat effects on skin. Numerous other extrinsic factors, related to environment and lifestyle, also affect the appearance of skin, precipitating ageing. New molecular mechanisms linking sun and environmental factors to skin ageing have been identified: IR affects mitochondrial integrity and specific heat receptors also mediate some of its effects, tryptophan is a chromophore for UVB, and the aryl hydrocarbon receptor (AhR) is activated by light and xenobiotics to alter skin physiology. Integrating all these new elements is changing the way we think about skin extrinsic ageing. Is UVA/UVB sunscreen protection still enough for our skin?R esum e Depuis les temps anciens, lesêtres humains ont essay e de prot eger leur peau contre les effets n efastes du soleil. Depuis les ecrans minraux d'abord utilis es par les Egyptiens, aux filtres solaires organiques sophistiqu es actuels (UVA/UVB), des progr es ont et e r ealis es en termes de protection contre le soleil, et une connaissance approfondie de la physiologie cutan ee a et e acquise durant ce temps. Le spectre solaire est compos e de radiations de longueurs d'onde diff erentes poss edant des effets sp ecifiques, ainsi que des effets redondants sur la peau. Les UVB sont les principaux responsables des coups de soleil et de la formation de dim eres d'ADN qui peuvent conduire a une mutation. Les UVA g en erent des r eactions d'oxydation qui affectent l'ADN, des prot eines, et les lipides, et agissent egalement comme immunosuppresseur. R ecemment, les rayonnements de la lumi ere visible et de l'infrarouge (IR) ont et e associ es a des dommages oxydatifs, et l'IR a et e en outre li e a des effets ind esirables de la chaleur sur la peau. De nombreux autres facteurs extrins eques li es a l'environnement et au mode de vie affectent aussi l'aspect de la peau, acc el erant le vieillissement. De nouveaux m ecanismes mol eculaires reliant le soleil et les facteurs environnementaux au vieillissement de la peau ont et e identifi es: l'IR affecte l'int egrit e mitochondriale; des r ecepteurs thermiques sp ecifiques servent egalement de m ediateur de certains de ses effets; le tryptophane est un chromophore UVB; le r ecepteur d'hydrocarbures aryles (AhR) est activ e p...

Synchrotron-based infrared microspectroscopy is a powerful technique for disentangling biochemical effects in nanoparticle-based radiotherapy approaches.

Objectives:Nucleoplasty is a minimally invasive procedure that is developed to treat patients with symptomatic, but contained disc herniations or bulging discs. The purpose of this study was to evaluate a decade follow-up of coblation nucleoplasty treatment for protruded lumbar intervertebral disc.Methods:In this retrospective study there a total 50 patients who underwent intradiscal coblation therapy for symptomatic, but contained lumbar degenerative disc disease were included. Relief of low back pain, leg pain and numbness after the operation were assessed by visual analog pain scale (VAS). Function of lower limb and daily living of patients were evaluated by the Oswestry disability index (ODI) and subjective global rating of overall satisfaction were recorded and analyzed.Results:There were 27 male and 23 female with followup mean follow up of 115 months (range 105–130 months) with a mean age was 52 years (range 26–74 years). Analgesic consumption was reduced or stopped in 90% of these cases after 1 year. At 24 months follow up VAS was four points and ODI was 7.2. In three patients, we repeated the cool ablation after 36 months, at L3–4 level in two cases. Ten patients continue to be asymptomatic after 114 months of intervention. There were no complications with the procedure including nerve root injury, discitis or allergic reactions.Conclusions:Nucleoplasty may provide intermittent relief in contained disc herniation without significant complications and minimal morbidity. In accordance with the literature the evidence for intradiscal coablation therapy is moderate in managing chronic discogenic low back pain; nucleoplasty appears to be safe and effective.

S u m m a r y . Forty patients with lumbar arachnoiditis, following previous operations, were classified into 4 myelographic types. Most patients with type I images had herniated disc symptoms with unilateral leg pain and limited straight-leg raising. Patients with types H and III myelographic appearances had bilateral leg pain, absent ankle jerks, weakness, cramps and signs of diffuse sensory deficit; some also had neurogenic claudication and urinary sphincter dysfunction. All patients with type IV had dysaesthesia. Twenty-three of the 40 patients underwent reoperation and those with types I and H had acceptable results, but poor results occurred in those with types III and IV myelograms. R6sum6. Quarante patients atteints d'arachno'idite lombaire ont ~t~ class& selon les images mydlographiques en quatre groupes. La plupart des patients avec une image de type I prdsentent des signes de hernie discale avec sciatalgies unilatdrales et limitation de l'extension de la jambe. Chez les patients pr&entant des caractdristiques mydlographiques de type H et III prddominent des sciatalgies bilatdrales, des spasmes musculaires, de la faiblesse, des crampes et des troubles sensitifs diffus. Quelques patients prdsentent un syndrome neurologique ddficitaire et une atteinte sphinctdrienne. Tous les malades avec des images mydlographiques de type IV ont des dysesthdsies. Vingt-trois patients sur quarante ont dtd rdopdrds. L'intervention a obtenu un r~sultat satisfaisant (bon et moyen) chez les patients avec des images mydlographiques de type I e t II. Chez ceux qui avaient des mydlographies de type III et IV les mauvais r6sultats ont dtd beaucoup plus frdquents.