Biomedical subjects

J-A Sahel

Publications and source records attributed to J-A Sahel.

7 recordsLinked to original sources

PubMed2006

Familial central retinal vein occlusion.

AIM: To report four cases of central retinal vein occlusion (CRVO) in a French family. PATIENTS AND METHODS: Ophthalmological examination and medical work-up of seven members of the family. RESULTS: There were four cases of CRVO in two consecutive generations. Three of them had CRVO in both eyes. Arterial hypertension was present in two, associated to glaucoma in one. Medical work-up did not reveal additional risk factors. CONCLUSIONS: We report a case of familial clustering of CRVO. Our cases combined to other cases reported in the literature provide arguments for the existence in some subjects of a genetic predisposition of CRVO. Additional case series are however needed to confirm this hypothesis.

Adult↗

PubMed2006

[Retinal stem cells: mechanism of differentiation and therapeutic application].

Retinal dystrophies are rarely curable diseases and several avenues of research are being pursued, such replacement therapies and pharmacological treatment. Among them, the transplantation of functional retinal cells has been envisaged in order to restore vision in patients who have these diseases by repopulating the damaged retina and/or by rescuing retinal neurons from further degeneration. Over the past few years, identification and characterization of stem cells has opened new avenues in cell-replacement therapy. Since retinal stem cells are already present during embryonic development, they persist in the adult mammalian eye only in the ciliary marginal zone, even a stem cell potential has been described for the Müller glia in the retina. This result opened possibilities of regeneration by mobilizing endogenous stem cells to respond to injury. Regarding the transplantation studies, in all experiments using different types of stem cells (retinal progenitors, neural stem cells, bone marrow-derived stem cells and ES cells), despite their incorporation within the host's retina, the transplanted cells failed to express retina-specific markers and to establish synaptic connections. Therefore, the true potential of the different stem cells in retina repair can only be realized with more information about mechanisms that regulate their proliferation and differentiation; and by development of techniques that allow their prospective identification and enrichment.

Animals↗

PubMed2006

[How to perform intravitreal injections].

Drugs to treat retinal diseases are often injected intravitreally. This procedure can cause severe complications. We present ways to minimize the risk for complications. Rigorous preoperative antisepsis with povidone iodine, a sterile environment (using gloves and a mask for the injector, a lid speculum, and a drape on the eye to be injected), and immediate follow-up after injection are key issues of the injection technique.

Humans↗

PubMed2005

GOAnno: GO annotation based on multiple alignment.

UNLABELLED: GOAnno is a web tool that automatically annotates proteins according to the Gene Ontology (GO) using evolutionary information available in hierarchized multiple alignments. GO terms present in the aligned functional subfamily can be cross-validated and propagated to obtain highly reliable predicted GO annotation based on the GOAnno algorithm. AVAILABILITY: The web tool and a reduced version for local installation are freely available at http://igbmc.u-strasbg.fr/GOAnno/GOAnno.html SUPPLEMENTARY INFORMATION: The website supplies a detailed explanation and illustration of the algorithm at http://igbmc.u-strasbg.fr/GOAnno/GOAnnoHelp.html.

Algorithms↗

PubMed2005

[Prevention of proliferative vitreoretinopathy using 5-FU heparin: clinical tolerance and efficacy].

PURPOSE: To study the safety and efficacy of adjuvant combination therapy using 5-fluorouracil and heparin for prevention of proliferative vitreoretinopathy (PVR) during vitrectomy for retinal detachment surgery. METHODS: Two consecutive groups of 30 eyes with a rhegmatogenous retinal detachment (grade C1 or more) were prospectively compared. In the study group, 5-FU and heparin were administrated in the intraoperative infusion. Clinical safety and the efficacy were regularly studied over 1 year. RESULTS: In the 5-FU heparin therapy group, keratitis was more frequently observed the 1st day after surgery (p = 0.005), but not after 1 week (p = 0.54). However, conjunctival hyperemia was more severe after 1 and 7 days (p = 0.04). In both groups, no differences were found concerning intraocular pressure, postoperative hemorrhage or inflammatory reaction (flare) of the anterior chamber and the aspect of the eyelids (p > or = 0.14). The number of reoperations resulting from PVR, after 1 month and 1 year, was not significantly different between the two groups (p > or = 0.3). The reattachment rate and visual acuity (BSCVA) were not statistically different after 1 year (p > or = 0.12). CONCLUSION: Adjuvant combination therapy using 5-FU and heparin seems to be safe. However, its efficacy needs to be demonstrated by larger studies including eyes presenting a lower grade of PVR (grade B).

Drug Therapy, Combination↗

PubMed2004

[Hereditary retinal pathologies and AMD: new therapeutic perspectives].

This article summarizes our current knowledge on two types of retinal diseases: hereditary retinal degeneration and wet aged-related macular degeneration. Our understanding of retinal physiopathology in hereditary retinal degeneration and the successful experimental therapeutic results on animal models call for a new approach to these patients to prepare future clinical trials. Longitudinal follow-up of the functional alteration rhythm based on international standards and by expert centers is an essential prerequisite to including these patients in future clinical trials. Creating international databases that include data on follow-up using electrophysiological, psychophysical and morphological analyses would require standards defining how each of these procedures should be carried out. Furthermore, the relevance and value of the various examinations would then be evaluated in a longitudinal manner. The repeated use of these procedures in the various centers would bring to light any limitations these techniques may have for use in prospective studies. Continuous re-evaluation of these investigative techniques will therefore be necessary, a crucial factor in the preparation of multicenter clinical studies. The inclusion of patients phenotyped at different centers would require that certification procedures be set up for these centers. A great leap forward, clinical trials on new antiangiogenic approaches for the treatment of neovascular AMD are currently underway. The reasons for the switch between the neovascular and atrophic forms of AMD are as yet unknown, but these new approaches are based on the events that occur sequentially during the angiogenic response.

Clinical Trials as Topic↗

PubMed2003

[Dacryolithiasis: diagnosis using nasal endoscopy].

PURPOSE: The purpose of this study was to assess the value of two new clinical findings for the diagnosis of dacryolithiasis discovered with nasal endoscopy: anatomical abnormalities of the Hasner valve (HV) and mucopurulent discharge visible at this valve. The value of these findings is compared with other clinical and radiological signs of dacryolithiasis. A hypothesis is developed as to the responsibility of the HV in the formation of dacryolithiasis. METHOD: This study was prospective and based on 797 operations performed for epiphora: 647 endonasal dacryocystorhinostomies and 150 meatotomies of the HV, with systematic preoperative nasal videoendoscopy. Ninety dacryocystographies (DCGs) and 129 lacrimal computed tomographies (LCT) were preoperatively performed. RESULTS: Dacryoliths were found in 55 of 797 patients (6.9%). The HV could be examined in 48 patients in the lithiasis group and in 687 patients in the control group. Mucopurulent discharge was observed in 22 patients with lithiasis (45.8%) and in 40 patients (5.8%) (p<10(-6)) of the control group. Anatomical abnormalities of the HV were found in 40 patients with dacryolithiasis (83.3%) as compared to 82 patients ing the control group (11.4%) (p<10(-6)). In 13 patients, the VH was very small (<2 mm), in 12 patients it was very long (>15 mm), and in 15 patients both abnormalities were observed. Other clinical signs were young age (mean, 48.2 years vs 59.1% in the control group) (p<0.05), a history of acute noninfectious dacryocystic retention (38.2% vs 9.5%) (p<10(-5)), partial obstruction of the lacrimal pathway (LP) (61.8% vs 30.5%) (p<10(-5)). The 28 LCTs that were performed in subjects who had lithiasis made it possible to diagnose 19 cases of dacryolithiasis and confirmed abnormalities of the HV causing narrowing of the LP in 20. CONCLUSION: Dacryolithiasis is frequent and often misdiagnosed. When dacryolithiasis is suspected, a nasal videoendoscopic exam must be done to seek HV abnormalities and mucopurulent discharge at this valve. This latter finding, i.e., the association of mucopurulent discharge with a patent lacrimal system, has high specificity. The finding of numerous anatomical abnormalities of the HV may be an indication that congenital malformation of the HV is the cause of many cases of lithiasis.

Adult↗