Light-induced charge generation in polymeric nanoparticles restores vision in advanced-stage retinitis pigmentosa rats.

Retinal dystrophies such as Retinitis pigmentosa are among the most prevalent causes of inherited legal blindness, for which treatments are in demand. Retinal prostheses have been developed to stimulate the inner retinal network that, initially spared by degeneration, deteriorates in the late stages of the disease. We recently reported that conjugated polymer nanoparticles persistently rescue visual activities after a single subretinal injection in the Royal College of Surgeons rat model of Retinitis pigmentosa. Here we demonstrate that conjugated polymer nanoparticles can reinstate physiological signals at the cortical level and visually driven activities when microinjected in 10-months-old Royal College of Surgeons rats bearing fully light-insensitive retinas. The extent of visual restoration positively correlates with the nanoparticle density and hybrid contacts with second-order retinal neurons. The results establish the functional role of organic photovoltaic nanoparticles in restoring visual activities in fully degenerate retinas with intense inner retina rewiring, a stage of the disease in which patients are subjected to prosthetic interventions.

[Renal angiomyolipoma and pulmonary lymphangiomyomatosis: a non-fortuitous association]. / Angiomyolipome rénal et lymphangiomyomatose pulmonaire: une association non fortuite.

Angiomyolipoma is a rare tumor, frequently associated with tuberous sclerosis, but not observed in its isolated form. Usually, patients with tuberous sclerosis presented with pathognomonic cutaneous and central nervous system lesions. But the thesis of "formes frustes" without typical stigmata was suggested. A case of bilateral and multifocal angiomyolipoma in a young woman without evidence of phacomatosis is reported. The association with a pulmonary lymphangiomatosis make us suspected "a forme fruste" of tuberous sclerosis.

Radiologic anatomy of the anastomotic systems of the internal iliac artery.

On the basis of 200 angiographic studies of atherosclerotic patients affected by aorto-iliac lesions, the authors have investigated the anastomotic collateral systems of the internal iliac artery. After defining the different anastomotic systems of the internal iliac artery, they attempt to assess the functional importance of each anastomotic system in relation to the level of aorto-iliac obstruction. The different anastomotic systems involved are studied in terms of the different types of obliteration of the main arterial axis, and clinical tolerance is assessed for each case. This study emphasizes the important role of the internal iliac artery in the compensatory circulation to the lower limbs, over and above its role as an artery supplying the pelvis. The authors consider that this justifies attaching great importance to revascularization of the internal iliac arteries during reconstructive aorto-femoral procedures.

[Gangrenous states of the perineum and genital region]. / Les états gangreneux du périnée et de la sphère génitale.

The authors report on 13 cases of gangrene of the perineum. Eight of the patients presented with a pre-existing infectious or tumoral anorectal lesion. In two cases, gangrene was a complication of a surgically treated prostatic pathology; two other patients had Fournier's disease. The last case was termed "spontaneous" as no causative factor was found. The unexpected recrudescence of this pathology, its severe nature, our limited knowledge of the pathogenic factors involved, and the difficulties encountered in treatment make analysis of this series of cases particularly interesting; moreover, despite the apparent etiological disparity of these observations, there were common anatomic, bacteriologic, and therapeutic elements. As concerns treatment, emphasis is placed on three points: prime role of surgery, the only means of obtaining precise information on lesions, broad indications for bypass colostomy, value of treatment with hyperbaric oxygen. The mortality rate remains high: 4 of the 13 patients died.

[Mechanical fatigue of an arterial prosthesis]. / Fatigue mécanique d'une prothèse artérielle.

This case study reports the analysis of a knitted polyester arterial prosthesis that was implanted in an 18-year old patient for five years following a bicycle accident which injured the left external iliac artery. In spite of the prosthesis, the patient continued to participate in competitive cycling. The graft became dilated and stretched by tension from the hypertrophic psoas muscle, and because the patient presented with pain and claudication, a second surgical operation was performed. The central region of the prosthesis was badly kinked. A segment was resected and analyzed in terms of pathological, textile and chemical properties. The analysis showed a poorly healed graft that had suffered from mechanical and chemical degradation. The findings point to the wisdom of implanting woven rather than knitted grafts in young patients and also suggest that in this particular case, where mechanical deterioration was accompanied by chemical degradation, it would have been preferable to remove the whole prosthesis.