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M Muraine

Publications and source records attributed to M Muraine.

35 records · Page 2Linked to original sources
PubMed1999

Cyclooxygenase-2 activity is necessary for the angiogenic properties of oncostatin M.

Macrophages play a major role in angiogenesis. We recently reported that oncostatin M (OSM), a cytokine of the interleukin (IL)-6 family secreted by macrophages, has a potent angiogenic activity on human microvascular endothelial cells (HMEC-1), but has no effect on macrovascular cells (human umbilical vein endothelial cells (HUVECs)). In this work, we show that in HMEC-1, OSM (0.5-2.5 ng/ml), leukemia inhibitory factor (LIF) (25 ng/ml), bFGF (25 ng/ml) and IL-1beta (5 ng/ml) induced production of cyclooxygenase (COX)-2. In contrast, in HUVECs, neither OSM nor LIF induced COX-2 mRNA, suggesting that COX-2 might be implicated in the angiogenic activity of OSM. This was confirmed by the inhibiting effect on OSM-induced HMEC-1 proliferation of specific COX-2 inhibitors. In vivo studies confirmed this findings. We conclude that induction of COX-2 by OSM is necessary for its angiogenic activity, but is not sufficient since IL-1beta, which also induces COX-2 in HMEC-1, has only a poor proliferative effect.

Animals↗
PubMed1999

Peribulbar anaesthesia during keratoplasty: a prospective study of 100 cases.

AIMS: A prospective study was carried out in order to evaluate the efficacy and safety of peribulbar anaesthesia during keratoplasty and to describe surgical conditions. METHODS: Of 137 consecutive keratoplasties, 100 (73%) were performed under peribulbar anaesthesia. Patients received a mean volume of 16.5 (SD 4) ml (range 9-22 ml) of a mixture of etidocaine, bupivacaine, and hyaluronidase. Ocular compression duration was at least 20 minutes and intraocular pressure (IOP) was measured with a Tonopen after injection, compression, and before trephination. Degree of akinesia, pain scoring, complications, and surgical conditions were studied. RESULTS: Before trephination, IOP was 5.73 mm Hg below the preinjection value and was never above 21 mm Hg. Akinesia was complete in 80% of cases and 94% of patients found that surgery was painless. Two patients (2%) were very agitated during surgery. The last patient presented with an acute intraoperative suprachoroidal haemorrhage that did not result in a true expulsive haemorrhage despite an "open sky" situation. Surgical conditions were judged to be optimal by the patients in 92% of cases and by the surgeon in 98% of cases. CONCLUSION: These results demonstrate that peribulbar anaesthesia offers excellent anaesthesia and akinesia during keratoplasty and may be recommended for this type of surgery.

Adolescent↗
PubMed1999

Oncostatin M induces angiogenesis in vitro and in vivo.

Neovascularization of the atherosclerotic plaque is responsible for its weakening and consequently for the complications of vascular disease. Macrophages are a source of growth factors that can modulate angiogenesis. In this study, we analyzed the effect of oncostatin M (OSM) on angiogenesis, as it could be involved in the development of atherosclerosis. The effect of OSM was compared with those of leukemia inhibitory factor (LIF) and interleukin-6 (IL-6). On human dermal microvasculature endothelial cells (HMEC-1s), OSM (22.5 to 112.5 pmol/L) induced a dose-dependent increase in cell proliferation greater than that induced by the classic angiogenic factors vascular endothelial growth factor (VEGF; 543 pmol/L) and basic fibroblast growth factor (bFGF; 1.1 nmol/L). LIF (19 to 475 pmol/L) induced only a 30% increase in cell proliferation, and IL-6 had no effect. Furthermore, in a modified Boyden-chamber model, OSM, LIF, and IL-6 were chemoattractant for HMEC-1s. In a tridimensional gel of fibrin, OSM increased tube formation and tube length, which were already noticeable by day 3. LIF and IL-6 induced a weaker effect that was only obvious by day 10. The angiogenic effect of OSM was also demonstrated in vivo in a rabbit corneal model: OSM was more potent than LIF, the length of the neovessels being longer with OSM than with LIF, whereas IL-6 was without effect. We tested factors that could be involved in the proliferative effect of OSM on HMEC-1s. OSM induced only a slight increase in the urokinase receptor and a 60% increase in VEGF secretion, whereas it does not modify IL-8 secretion or bFGF levels. The effect of OSM seems to depend on endothelial cell origin and cell species: OSM (up to 112.5 pmol/L) did not induce human umbilical vein endothelial cell proliferation and even had a small inhibitory effect (17%) on calf pulmonary artery endothelial cells. In conclusion, OSM induces an angiogenic effect on capillary endothelial cells, which could be, at least in part, implicated in pathological processes such as atherosclerosis or tumor growth.

Capillaries↗
PubMed1999

[Non-penetrating deep sclerectomy in the surgical treatment of chronic open-angle glaucoma. Mid-term results].

PURPOSE: Non-penetrating deep sclerectomy has been performed in France since the early nineties and appears to be an interesting alternative to Cairn's trabeculectomy. The technical characteristics, the ability to use antimitotic procedures and postoperative YAG laser goniotomy contribute to make deep sclerectomy an attractive surgical method. We evaluated its efficacy and adverse effects in a mid-term retrospective series. PATIENTS AND METHODS: Fifty patients (all POAG) without usually accepted failure risks for trabeculectomy (trabeculoretraction less than 3 months, intraocular anterior or posterior lens, aphakia, black or Asian subject, failure of previous surgical procedure, patients under 40) underwent this surgical procedure between June 96 and October 97 performed by several skilled surgeons in our unit. This was the first antiglaucoma surgical procedure for all patients. Collagen draining implant was not used. Two pressure criteria (21 mmHg and 16 mmHg) were used to assess success. Success rate and adverse effects were compared with previously published data using the Kaplan-Meier test. RESULTS: Medium follow-up was 14.24 months. The success rate was 81% (IOP 21 mmHg) and 50% (IOP 16 mmHg) at maximum follow-up of 18 months. There was no statistical difference between treated and untreated groups for target IOP at 21 mmHg (p = 0.12). These results were comparable to those in previous studies and to those obtained with trabeculectomy. The complication rate was low (hyphema 0%, choroidal detachment 2%, hypothalamia 2%, endocular infection 0%). DISCUSSION: Our success rate and complication rate were comparable with previously published series. Choosing a target IOP of 16 mmHg allowed a better comparison between daily clinical observations and mid-term results, showing a significant difference from the 21 mmHg target. Nevertheless, the success rate was comparable to that obtained with trabeculectomy and the complication rate was lower, supporting the favorable opinion concerning deep sclerectomy. CONCLUSION: Non-penetrating deep sclerectomy appears to be as efficient as Cairn's trabeculectomy for surgical treatment of glaucoma and allows a lower complication rate. Long-term results, visual field and papilla remain to be evaluated. Furthermore, results with a pressure goal of 16 mmHg are interesting to evaluate because they reflect the real clinical situation better than the target 21 mmHg IOP. This technique should be evaluated in other forms of glaucoma.

Actuarial Analysis↗
PubMed1999

[Peribulbar anesthesia for peroperative and postoperative pain control in eye enucleation or evisceration: 31 cases].

OBJECTIVES: The aim of this prospective study was to assess peroperative and postoperative analgesia in eye enucleation or evisceration performed under peribulbar anesthesia. PATIENTS AND METHODS: We report 31 patients undergoing an eye enucleation (17 cases) or evisceration (14 cases). The surgical procedure was performed under local anesthesia alone in 22 patients. General anesthesia was associated with local anesthesia in 9 patients. Peribulbar block was achieved with the first insertion of the needle parallel to the inferior orbital floor and the second at level of supraorbital notch. A mixed anesthetic solution of equal quantity of lidocaine 2% with epinephrine (0.25 mg/20 ml) and bupivacaine 0.50% with epinephrine (0.10 mg/20 ml) was injected (total quantity 16.8 +/- 4.3 ml). RESULTS: To assess the peroperative pain we considered the patients with local anesthesia only (22 patients). One of these 22 patients needed one injection (0.50 mg/kg) of propofol for cutting the optic nerve. Surgery was ended without any other drug but that case was considered as a failure. Peroperative analgesia was obtained in 21 of 22 patients (95.4%). To assess analgesia in the postoperative period we included 31 patients. Analgesia was complete from the accomplishment of the peribulbar block to the 4th hour in all patients (efficacy 100%). From the 4th to the 24th hour, pain remained absent in 11 (enucleation 10 cases and evisceration 1 case) of the 31 patients and no drug was used. In 20 patients (enucleation 7 cases and evisceration 13 cases), pain appeared between the 4th and the 10th hour and patients were relieved by paracetamol alone in 14 cases (enucleation 6 cases and evisceration 8 cases) or by its association with nalbuphine in 5 cases (enucleation 1 case and evisceration 4 cases). In one patient (evisceration) the association of the drugs was uneffective. CONCLUSION: Peribulbar anesthesia is safe and generates major postoperative analgesia so we suggest to offer that technique to patients undergoing evisceration or enucleation.

Acetaminophen↗
PubMed1997

Detection and genotyping of the hepatitis C RNA in tear fluid from patients with chronic hepatitis C.

Tear fluid from 51 patients with chronic hepatitis C virus (HCV) infection was analyzed for the presence of the hepatitis C RNA to assess the potential role of this fluid in virus transmission. HCV sequences were amplified from sera and tear fluids by nested polymerase chain reaction using primers from the 5' non coding region of the virus genome. Positive samples were genotyped by the LiPA procedures. HCV RNA was detected in 76.5% (39/51) of the sera and in 9.8% (5/51%) of the tear fluid samples. The presence of the RNA in the tear fluid was independent of the severity of the hepatitis and of the viral load as measured by the branched DNA assay. The genotypes of the tears and serum isolates were different for two patients. For another patient, the HCV RNA was positive in the tear sample but negative in the serum sample. These findings suggest that tear fluid may transmit HCV but the source of HCV RNA in this fluid needs to be better understood.

Chronic Disease↗
PubMed1997

[An important step in cornea procurement: interview with the family of donors].

BACKGROUND: Since bioethic laws were promulgated in France in 1994, post-mortem cornea procurement can be achieved only after donor's family consent. In order to fulfil this task, we set up a group of individuals including ophthalmologists and members of the coordination team. The aim of this study was to establish the efficiency of such a group and to evaluate the content of donor's family interview. METHODS: During this 14-month prospective study, we analyzed all the interviews we performed with donor families. To report these interviews, we used a preestablished questionnaire. RESULTS: We met 60 families during this study. Procurement rate was 80%. This acceptance was mostly facilitated by advanced mean donor's age (65 years) and by the 12-hour period of time allowed after donor's death. The other important factors were the terms of the interviews, the commitment for a perfect anatomical restoration. We noticed that usually (83%), the family was not aware of donor's last will and had unfortunately to make a choice. Accepting to wait for a final decision helped getting a positive response (86%) and even sometimes helped to reconsider a previous negative position (10%). CONCLUSION: Because of a dramatic lack of corneal grafts in France, more than 7000 patients are on a waiting list. Our results show that positive response can be obtained from the donor's family when a trained group manages the donation request. We strongly suggest that each eye bank create such a group.

Adult↗
PubMed1997

Interleukin-6 in tear fluid after photorefractive keratectomy and its effects on keratocytes in culture.

PURPOSE: To investigate the participation of interleukin-6 (IL-6) after photorefractive keratectomy (PRK) and its possible roles and sources in corneal wound healing. METHODS: IL-6, levels were measured in the tear fluids of patients before and after PRK and in conditioned media of human corneal epithelial cells and keratocytes. Its effects on total collagen and collagen-type synthesis by keratocytes were studied with a 3H-proline incorporation assay and Northern blot analysis. Zymography was used to evaluate the metalloproteinase content in the conditioned medium of IL-6-stimulated keratocytes. RESULTS: IL-6 is present in the tear fluid samples after photorefractive keratectomy, possibly synthesized by epithelial cells and keratocytes. CONCLUSIONS: IL-6 stimulates collagen synthesis in general and collagen type I in particular. Furthermore, it reduces the production of MMP-2, the latent form of the metalloproteinase, by cultured keratocytes. The results suggest that IL-6 might be regarded as a mediator involved in corneal healing after excimer laser.

Adult↗
PubMed1996

[Paradoxical aggravation of carotid cavernous fistula].

A case of spontaneous thrombosis of carotid cavernous fistula, preceded by paradoxical worsening of ocular symptoms occurred in a 74-year-old patient. Clinical examination, and paraclinical investigation if necessary (echo-Doppler and arteriography) allow to distinguish spontaneous resolution from increased blood flow through the fistula.

Aged↗
PubMedDate not supplied

Spontaneous resolution of vitreomacular traction associated with diabetic macular edema.

PURPOSE: Little information is available about the natural history of vitreomacular traction (VMT) associated with diabetic macular edema. A few cases of spontaneous resolution of VMT associated with diabetic macular edema have been described, but have not been documented by optical coherence tomography (OCT). The authors report the spontaneous resolution of VMT associated with diabetic macular edema 1 month after the end of panretinal photocoagulation therapy (PRP). METHODS CASE REPORT: A 66-year-old woman presented with complicated proliferative diabetic retinopathy and diabetic macular edema associated with VMT, documented by OCT, in the right eye. Left eye examination showed complete PRP and ischemic maculopathy. PRP was immediately realized in the right eye in regard to the presence of complicated proliferative diabetic retinopathy. RESULTS: One month after the end of PRP, right eye visual acuity improved. OCT examination showed complete release of foveal posterior hyaloid traction, and significant reduction in foveal thickness. The follow-up was 1 year. At the end of follow-up, visual acuity slightly improved again; only a small residual foveal retinal thickening remained. CONCLUSIONS: The authors report spontaneous resolution of VMT associated with diabetic macular edema, probably facilitated by PRP, with concurrent reduction of macular thickness and visual improvement. As spontaneous resolution may occur in some eyes with diabetic macular edema associated with VMT, a period of observation after the end of the PRP may be considered prior to vitrectomy.

Aged↗