Biomedical subjects
Publications and source records attributed to J Royer.
During simple inspection of an inflamed eye it is often difficult to diagnose an infection. However, infection must be suspected, notably in cases with facilitating factors. Eye infection requires management by specialists to prevent complications which might endanger vision.
We have isolated a novel inhibitor of erythropoietic differentiation from the plasma of a patient suffering from idiopathic pure red cell aplasia. This differentiation-inhibiting protein (DIP) specifically blocked the differentiation of human burst-forming unit-erythroid (BFU-E), but not colony-forming unit-erythroid (CFU-E) cells. DIP also blocked the maturation of murine BFU-E cells, but not CFU-E or CFU-granulocyte-macrophage cells, and it inhibited the dimethyl sulfoxide (DMSO)-induced differentiation of Friend murine erythroleukemia cells (FLC) at levels between 10(-10) and 10(-12) mol/L. DIP activity was not detectable in the plasma of normal, healthy subjects. Unlike other known inhibitors of hematopoiesis, DIP appears to directly inhibit erythropoietic differentiation, because it did not affect the proliferation of untreated FLC and it effectively blocked FLC hemoglobinization without affecting the ability of the blocked cells to proliferate. DIP blocked FLC differentiation only when added to the culture medium within 1 hour of inducing the cells with DMSO, suggesting that the protein inhibited an early, but critical, DMSO-induced cellular process. DIP appears to be at least partially responsible for the patient's anemia, and its unique activity suggests a role in the early development of some erythroleukemias.
Data concerning the biomechanical properties of IOL are rare. A systematic study of these properties was performed in the "laboratoire de Mécanique des Structures" at the "Ecole Centrale de Nantes". The results of the anteroposterior displacement of the optical part of eleven posterior chamber lenses (all PMMA) which were subjected to a diameter reduction, are reported. The deplacement of the implants was very slight and the position of the posterior side was relatively anterior whatever the diameter of insertion. The clinical implications, especially concerning the posterior capsule, are discussed.
The multiple-dose twice-daily efficacy of the topical carbonic anhydrase inhibitor MK-927, a racemic compound, was compared with that of its pharmacologically more active S-enantiomer in a four-center, double-masked, randomized, placebo-controlled, parallel study of 1.8% sezolamide hydrochloride (MK-417), 2% MK-927, and placebo, given twice daily to 48 patients with bilateral primary open angle glaucoma or ocular hypertension and morning intraocular pressure greater than 24 mm Hg in both eyes following washout of ocular hypotensive medications. Parallel 10-hour modified diurnal curves were performed before the study and on day 14, with 4-hour curves on days 1 and 4. Both compounds demonstrated significant lowering of intraocular pressure at 8 AM, 12 hours following the evening dose, and through 10 and 6 hours following the 8 AM dose for sezolamide and MK-927, respectively. Morning trough (evening) activity as measured by mean percent change in intraocular pressure from prestudy was -9.2% for sezolamide and -11.1% for MK-927 (-13.5% and -9.6%); peak effect occurred 2 hours after dose administration and was -19.4% and -19.2% for sezolamide and MK-927, respectively. From 2 hours after dose administration, sezolamide consistently demonstrated a slightly greater decrease in intraocular pressure than MK-927; however, these differences were not statistically significant.
We have isolated an erythropoiesis-inhibiting protein, DIP (differentiation-inhibiting protein), from the blood of a 60-year-old woman suffering from pure red cell aplasia. This protein inhibits the growth and differentiation of normal human and murine BFU-E, but not CFU-E, cells as well as dimethyl sulfoxide-induced hemoglobin synthesis by Friend murine erythroleukemia cells. It appears that DIP primarily affects differentiation rather than proliferation, because it does not inhibit the proliferation of untreated Friend erythroleukemia cells. DIP seems to function like a recently described 45-kDa autocrine differentiation-inhibiting protein factor (ADIF) which is secreted by tsAEV-transformed chicken erythroleukemia cells. Both proteins selectively block the differentiation of normal human and murine BFU-E cells as well as the differentiation (but not the proliferation) of Friend murine erythroleukemia cells. However, the human DIP is not an autocrine product of the patient's bone marrow cells, nor does it affect chicken erythroid cells.
This study using electrical extensometry is aimed at comparing the relative deformations of the same fresh femur before and after the successive implantation of the following titanium prostheses: a cement-free prosthesis with metaphyseal endocortical support, a cemented prosthesis with, then without collar, and finally a screwed titanium prosthesis. The 56 deformation measurement paths produce an overall exploration of the behavior of the femur. The results applied to the same straight section of the femur are different from those of earlier works. The density of the measurement areas has particularly been increased in the upper metaphysis by the use of bidirectional gages. The loading device ensures the absence of variations of the external stress torsion transmitted to the femur between the individual prostheses. The results recorded with the cement-free prosthesis with metaphyseal endocortical support and with the collar-free cemented prosthesis are very similar. The incidence of the "collar effect" is very low in spite of optimal in vitro implantation conditions ensuring good contact between the collar and the neck of the femur. The screwed prosthesis is the implant that most stiffens the upper end of the femur. The testing procedure chosen has allowed recording the deformations caused by the mere insertion of the implants and the bone. The importance of the upper metaphysea endocortical support of the cement-free, screwless implant contributes in ensuring a better primary anchorage, producing stresses that will then foster the secondary anchorage through endosteal osteogenesis.
The authors compared the growth of limbal and central explants removed from human cornea. Epithelial growth began on the third day, was greater during the first week and was subsequently slightly invaded by fibroblasts. This study demonstrated that peripheral corneal epithelial cells growth better than central cells. In this study, the cytologic and histologic features of the cells were examined. However, epithelial immunofluorescence staining by anti-cytokeratin antibodies was rather poor. This in vitro system may provide a suitable model for epithelial human corneal cell culture, allowing further biocompatibility studies.
The study of the spaces between the metacarpal heads on 23 cadavers, raises the question of the existence of bursae at this level. This is in line with recent studies suggesting that such bursae are present at this level in the foot. Careful dissection and histological studies revealed characteristics compatible with both of the following hypotheses: either the existence of bursae not described until now in anatomy text-books, or spaces limited by a cul-de-sac of the aponeuroses of the hand in the 2nd, 3rd and 4th digits. Tissue analyses that could determine more specifically the nature of the limiting membrane of these spaces, as well as pathological studies demonstrating the occurrence of common anomalies of bursae in these spaces, are required in order to conclude definitively the nature of the spaces between the metacarpal heads. The gross anatomical and histological characteristics of the spaces between the metacarpal and metatarsal heads and of their limiting membranes were compared and found to be analogous in our series.
Fresh human corneas and corneal buttons were studied for expression of HLA antigens. Using monoclonal antibodies in an indirect immunofluorescence assay, corneal layers were examined for class I (HLA-A, B, C) and class II (HLA-DR) histocompatibility antigens. Twenty-one human corneas were studied, 6 normal and 15 pathological: 4 buttons of allograft rejection, 9 buttons of pseudophakic bullous keratopathy. In fresh control corneas, HLA-A, B, C antigens were localized on corneal epithelium and on stromal keratocytes but were never found on endothelial cells. HLA-DR antigens were not detected on corneal epithelium, stroma or endothelium but were detected on Langerhans cells within epithelium and anterior stroma. At the corneal limbus, HLA class I-II antigens were expressed on vascular endothelium. HLA antigen distribution was modified in pathological corneas. Antigens HLA-A, B, C were induced on endothelial cells of rejected corneal allografts. Antigens HLA-DR were detected on epithelial cells, cells in the stroma of pseudophakic bullous keratopathy and also on endothelial cells of rejected corneal allografts. These results suggest that induction of class I and II antigen expression by inflammatory factors may occur in vivo. In rejected corneal allografts induction of HLA-DR antigen on corneal layers would intensify the process of rejection. This study and others have demonstrated the ability of modulation of HLA antigen expression on human corneal cells in vivo.
The present paper reports on the case of a 44 year-old woman with progressive facial hemiatrophy associated with bilateral papillitis who developed an acquired complete third nerve palsy on the unaffected side six months later. This Romberg's disease occurred in the context of an immunologic disturbance which was barely improved by steroids and Disulone. Ophthalmic involvement, particularly neurologic involvement, pathogenic hypothesis are reviewed. The responsibility of sympathetic disorder in Parry-Romberg disease is based on frequent association of progressive facial hemiatrophy and Fuch's and Horner's syndromes.
This study reports donor corneas stored at +37 degrees C in organ culture incubation. The follow up is 12 months. The graft survival is 92%. Two grafts are failed before 6 months. The mean control thickness is 0.54 mm and the mean endothelial cell density 1625 cells per mm2. A mean decrease in cell density of 40.6% is recorded. This study demonstrates that banked donor material can be successfully employed for corneal transplantation.
SSPE is a panencephalitis who involves children and who leads to death. It is due to a defective measles virus. Ophthalmologic features are frequent and may be the first manifestation of the disease. The most typical ocular involvement is retinitis which can be misdiagnosed as a toxoplasmosis.
The purpose of our study was to evaluate the individual variations of the foramen sometimes has the same dimensions as the foramen of the other cervical vertebrae, but it can also be smaller, or absent. In cases where the foramen is present in the seventh cervical vertebra, vascular or nerve structures (or both) can be occasionally observed within. When the transverse foramina are found to contain none of the above structures, what then is to be found within this space? According to our results, the transverse foramina of the seventh cervical vertebra almost universally contain vascular and nerve branches as well as fibrous and adipose tissue. This report concerns the results of the macroscopic and microscopic studies concerning the contents of the transverse foramina of the seventh cervical vertebra.
This study used peripheral human corneal epithelium in tissue culture. Cells were observed in cytology, histology and by immunofluorescence staining. This in vitro-system may provide a suitable model to study biocompatibility but also to collect free human corneal cells.
A study of 36 penetrating keratoplasties using donor corneas stored at +37 degrees C in organ culture incubation for an average of 12 days prior to transplantation is reported. The criteria for the survival of corneal grafts were mean central corneal thickness, clarity of the cornea and mean endothelial cell density. A total of 86% of the grafts remained clear after 12 months follow-up time. The mean central corneal thickness was 0.47 mm. The mean endothelial cell density was 1452 cells/mm2. Based on the results of this study, organ culture reported here appears to be a safe and efficient method of medium to long-term corneal storage.
Choroid osteoma was described for the first time by GASS in 1978. Today only 53 cases were reported in 39 patients. Using 3 new cases recently discovered in our region, we try to assess with the help of the already published data, the main points of the disease and its diagnostic.
The term "pre-equatorial syndrome" covers post-traumatic involvement of the anterior segment and of the pre-equatorial retina, due to a frontal distension mechanism. In a retrospective study, we studied 582 cases of ocular contusions from 1973 to 1986 in patients who required a brief hospitalisation in our clinic because of the severity of the initial injury. The aim of the study was to assess the occurrence of this syndrome, its clinical features and evolution. 59 complete pre-equatorial syndromes were found in this sample (10.2% of all the ocular contusions). The follow up ranged from one to 168 months. Games and sports injuries in children and work injuries in young men were most commonly found causes (2/3 of the cases). Hyphema and angle recession were the most frequently observed lesions (69%). All hyphemas disappeared spontaneously without surgical drainage. Subluxation of the lens was present in 10.6% and late post traumatic cataract occurred in four cases; all eyes were operated on by intracapsular extraction, three of them in the first year following the traumatism and the last twelve years latter. Intraocular pressure was high in 15.3% (but was easily controlled) and was very low in 5.1%. Retinal edema and haemorrhages were the most common involvement of the peripheral retina. Retinal dialysis was noticed in 13.6% especially in the upper nasal area: buckling surgery was performed in these cases with good results. Anterior and peripheral retinal damages was situated on the same meridian in 80% of the cases, five eyes showed a 180 degrees opposite setting while there was no obvious alignment in 15 of the cases. This syndrome did not impair final visual function alone, whereas severe associated ocular contusions of the posterior pole gave a very low visual outcome in 16 cases. This retrospective review emphasizes the main characteristics of this syndrome. Accurate examination of the irido-corneal angle and peripheral retina is of paramount importance in every ocular contusion.
Authors have studied the penetration of ciprofloxacin in the aqueous humor of 30 patients (30 eyes). The concentration in the anterior chamber was on average 0.73 mg/l (33% of serum level), from 1.30 hours after a single oral dose (1000 mg) till the 5th hour after this dose. The samples were assessed by a microbiological method. These results are over the minimal inhibitory concentration for many bacterial agents found in endophthalmitis. So this antibiotic may be proposed in the treatment of endophthalmitis, with further investigations assessing the safety of this procedure.