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This work was supported by the the University of Tours (to IDP and FDG), the University of Montpellier (to SD and EC), the Deutsche Forschungsgemeinschaft (to RTS), the Wellcome Trust project grant 093228 (to TKS) and the Campus France/DAAD PHC PROCOPE 24931RE (to RTS and EC). The funding source has no involvement in the conduct of the research and preparation of the article. Glycosylphosphatidylinositols (GPIs) are glycolipids described as toxins of protozoan parasites due to their inflammatory properties in mammalian hosts characterized by the production of interleukin (IL)-1, IL-12 and tumor necrosis factor (TNF)-α. In the present work, we studied the cytokines produced by antigen presenting cells in response to ten different GPI species extracted from Babesia divergens, responsible for babesiosis. Interestingly, B. divergens GPIs induced the production of anti-inflammatory cytokines (IL-2, IL-5) and of the regulatory cytokine IL-10 by macrophages and dendritic cells. In contrast to all protozoan GPIs studied until now, GPIs from B. divergens did not stimulate the production of TNF-α and IL-12, leading to a unique Th1/Th2 profile. Analysis of the carbohydrate composition of the B. divergens GPIs indicated that the di-mannose structure was different from the evolutionary conserved tri-mannose structure, which might explain the particular cytokine profile they induce. Expression of major histocompatibility complex (MHC) molecules on dendritic cells and apoptosis of mouse peritoneal cells were also analysed. B. divergens GPIs did not change expression of MHC class I, but decreased expression of MHC class II at the cell surface, while GPIs slightly increased the percentages of apoptotic cells. During pathogenesis of babesiosis, the inflammation-coagulation auto-amplification loop can lead to thrombosis and the effect of GPIs on coagulation parameters was investigated. Incubation of B. divergens GPIs with rat plasma ex vivo led to increase of fibrinogen levels and to prolonged activated partial thromboplastin time, suggesting a direct modulation of the extrinsic coagulation pathway by GPIs. Publisher PDF

International audience; Neospora caninum causes abortion in ruminants, leading to important economic losses and no efficient treatment or vaccine against neosporosis is available. Considering the complexity of the strategies developed by intracellular apicomplexan parasites to escape immune system, future vaccine formulations should associate the largest panel of antigens and adjuvants able to better stimulate immune responses than natural infection. A mucosal vaccine, constituted of di-palmitoyl phosphatidyl glycerol-loaded nanoparticles (DGNP) and total extract (TE) of soluble antigens of Toxoplasma gondii, has demonstrated its efficacy, decreasing drastically the parasite burden. Here, DGNP were loaded with N. caninum TE and glycosylphosphatidylinositol (GPI) of N. caninum as Toll-like receptor (TLR) adjuvant able to induce specific cellular and humoral immune responses. Activation of TLR2 and TLR4 signalling pathway in HEK reporter cells induced by GPI was abrogated after its incorporation into DGNP. However, in murine bone marrow-derived dendritic cells, an adjuvant effect of GPI was observed with higher levels of interleukin (IL)-1β, reduced levels of IL-6, IL-12p40 and IL-10, and decreased expression of major histocompatibility complex (MHC) molecules. GPI also modulated the responses of bovine peripheral blood mononuclear cells, by increasing the production of IFN-γ and by decreasing the expression of MHC molecules. Altogether, these results suggest that GPI delivered by the DGNP might modulate cell responses through the activation of an intracellular pathway of signalisation in a TLR-independent manner. In vivo experiments are needed to confirm the potent adjuvant properties of N. caninum GPI in a vaccine strategy against neosporosis.

Formation of retinal folds is a serious and possibly underreported complication of vitrectomy with intraocular gas for retinal detachment. Certain risk factors are associated with this complication. Presentation of our own cases with retinal folds after retinal detachment surgery and review of the relevant literature. Spontaneous resolution of a retinal fold without surgical intervention with excellent visual outcome was observed in a patient operated with vitrectomy and intraocular gas for retinal detachment. In another case surgical intervention with repeat vitrectomy and macular detachment followed by intraocular gas resulted in complete resolution of a retinal fold with excellent visual outcome. Retinal fold formation after vitrectomy for superior bullous retinal detachments running through the fovea can be managed both conservatively and surgically. Treatment decision is made on an individual basis depending on patient symptoms. Knowledge of the risk factors for fold formation and postoperative posturing after retinal detachment surgery is very important in order to avoid this complication.

International audience; Neosporosis due to Neospora caninum causes abortions in farm animals such as cattle. No treatment and vaccine exist to fight this disease, responsible for considerable economic losses. It is thus important to better understand the immune responses occurring during the pathogenesis to control them in a global strategy against the parasite. In this context, we studied the roles of N. caninum glycosylphosphatidylinositols (GPIs), glycolipids defined as toxins in the related parasite Plasmodium falciparum. We demonstrated for the first time that GPIs could be excreted in the supernatant of N. caninum culture and trigger cell signalling through the Toll-like receptors 2 and 4. In addition, antibodies specific to N. caninum GPIs were detected in the serum of infected mice. As shown for other protozoan diseases, they could play a role in neutralizing GPIs. N. caninum GPIs were able to induce the production of tumour necrosis factor-α, interleukin(IL)-1β and IL-12 cytokines by murine macrophages and dendritic cells. Furthermore, GPIs significantly reduced expression of major histocompatibility complex (MHC) molecules of class I on murine dendritic cells. In contrast to murine cells, bovine blood mononuclear cells produced increased levels of IFN-γ and IL-10, but reduced levels of IL-12p40 in response to GPIs. On these bovine cells, GPI had the tendency to up-regulate MHC class I, but to down-regulate MHC class II. Altogether, these results suggest that N. caninum GPIs might differentially participate in the responses of antigen presenting cells induced by the whole parasite in mouse models of neosporosis and in the natural cattle host.

Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe respiratory disease in humans. We tested a recombinant modified vaccinia virus Ankara (MVA) vaccine expressing full-length MERS-CoV spike (S) glycoprotein by immunizing BALB/c mice with either intramuscular or subcutaneous regimens. In all cases, MVA-MERS-S induced MERS-CoV-specific CD8 + T cells and virus-neutralizing antibodies. Vaccinated mice were protected against MERS-CoV challenge infection after transduction with the human dipeptidyl peptidase 4 receptor. This MERS-CoV infection model demonstrates the safety and efficacy of the candidate vaccine.

International audience; The haemoflagellate Trypanosoma cruzi is the causative agent of Chagas' disease that occurs in approximately 8 million people in Latin America. Patients infected with T. cruzi frequently suffer of cardiomegaly and may die of myocardial failure. Here we show that T. cruzi trypomastigotes (extracellular form) increased in vitro apoptosis of rat cardiomyocytes. Additionally, we demonstrated that amastigotes (intracellular form), for which a method for purification was established, were also able to induce cardiomyocyte apoptosis. Increase of apoptosis was associated with up-regulation of the apoptotic gene bax by trypomastigotes, while expression of the anti-apoptotic gene bcl-2 was down-regulated by amastigotes. The transcription factor STAT3 but not STAT1 was activated in cardiomyocytes by trypomastigotes. In addition, tlr7 gene expression was up-regulated in cardiomyocytes incubated with trypomastigotes, suggesting that this Toll-like receptor is involved in the intracellular recognition after host cell invasion by T. cruzi. Glycosylphosphatidylinositols purified from trypomastigotes did not induce cardiomyocyte apoptosis and STAT activation but down-regulated tlr7 gene expression. In conclusion, cardiomyopathy observed in Chagas' disease might be in part due to apoptosis of cardiomyocytes induced directly by the parasite.

In 2012, the first cases of infection with the Middle East respiratory syndrome coronavirus (MERS-CoV) were identified. Since then, more than 1,000 cases of MERS-CoV infection have been confirmed; infection is typically associated with considerable morbidity and, in approximately 30% of cases, mortality. Currently, there is no protective vaccine available. Replication-competent recombinant measles virus (MV) expressing foreign antigens constitutes a promising tool to induce protective immunity against corresponding pathogens. Therefore, we generated MVs expressing the spike glycoprotein of MERS-CoV in its full-length (MERS-S) or a truncated, soluble variant of MERS-S (MERS-solS). The genes encoding MERS-S and MERS-solS were cloned into the vaccine strain MV vac2 genome, and the respective viruses were rescued (MV vac2 -CoV-S and MV vac2 -CoV-solS). These recombinant MVs were amplified and characterized at passages 3 and 10. The replication of MV vac2 -CoV-S in Vero cells turned out to be comparable to that of the control virus MV vac2 -GFP (encoding green fluorescent protein), while titers of MV vac2 -CoV-solS were impaired approximately 3-fold. The genomic stability and expression of the inserted antigens were confirmed via sequencing of viral cDNA and immunoblot analysis. In vivo , immunization of type I interferon receptor-deficient (IFNAR −/− )-CD46Ge mice with 2 × 10 5 50% tissue culture infective doses of MV vac2 -CoV-S(H) or MV vac2 -CoV-solS(H) in a prime-boost regimen induced robust levels of both MV- and MERS-CoV-neutralizing antibodies. Additionally, induction of specific T cells was demonstrated by T cell proliferation, antigen-specific T cell cytotoxicity, and gamma interferon secretion after stimulation of splenocytes with MERS-CoV-S presented by murine dendritic cells. MERS-CoV challenge experiments indicated the protective capacity of these immune responses in vaccinated mice. IMPORTANCE Although MERS-CoV has not yet acquired extensive distribution, being mainly confined to the Arabic and Korean peninsulas, it could adapt to spread more readily among humans and thereby become pandemic. Therefore, the development of a vaccine is mandatory. The integration of antigen-coding genes into recombinant MV resulting in coexpression of MV and foreign antigens can efficiently be achieved. Thus, in combination with the excellent safety profile of the MV vaccine, recombinant MV seems to constitute an ideal vaccine platform. The present study shows that a recombinant MV expressing MERS-S is genetically stable and induces strong humoral and cellular immunity against MERS-CoV in vaccinated mice. Subsequent challenge experiments indicated protection of vaccinated animals, illustrating the potential of MV as a vaccine platform with the potential to target emerging infections, such as MERS-CoV.

GPIs isolated from Toxoplasma gondii, as well as a chemically synthesized GPI lacking the lipid moiety, activated a reporter gene in Chinese hamster ovary cells expressing TLR4, while the core glycan and lipid moieties cleaved from the GPIs activated both TLR4- and TLR2-expressing cells. MyD88, but not TLR2, TLR4, or CD14, is absolutely needed to trigger TNF-α production by macrophages exposed to T. gondii GPIs. Importantly, TNF-α response to GPIs was completely abrogated in macrophages from TLR2/4-double-deficient mice. MyD88−/− mice were more susceptible to death than wild-type (WT), TLR2−/−, TLR4−/−, TLR2/4−/−, and CD14−/− mice infected with the ME-49 strain of T. gondii. The cyst number was higher in the brain of TLR2/4−/−, but not TLR2−/−, TLR4−/−, and CD14−/−, mice, as compared with WT mice. Upon infection with the ME-49 strain of T. gondii, we observed no decrease of IL-12 and IFN-γ production in TLR2-, TLR4-, or CD14-deficient mice. Indeed, splenocytes from T. gondii-infected TLR2−/− and TLR2/4−/− mice produced more IFN-γ than cells from WT mice in response to in vitro stimulation with parasite extracts enriched in GPI-linked surface proteins. Together, our results suggest that both TLR2 and TLR4 receptors may participate in the host defense against T. gondii infection through their activation by the GPIs and could work together with other MyD88-dependent receptors, like other TLRs or even IL-18R or IL-1R, to obtain an effective host response against T. gondii infection.

Glycosylphosphatidylinositols (GPIs) are involved in the pathogenicity of protozoan parasites and are known to induce inflammatory cytokines. However, we have previously shown that the family of six GPIs of Toxoplasma gondii extracted together from tachyzoites could not induce tumor necrosis factor alpha (TNF-α) secretion by macrophages, whereas GPIs individually separated from this extract by thin-layer chromatography (TLC) were able to stimulate the cells. In the present study we show that the TLC step makes it possible to eliminate inhibitors extracted together with the T. gondii GPIs. Among the non-GPI molecules we have isolated fatty acids able to inhibit the secretion of TNF-α induced by the T. gondii GPIs. Myristic and palmitic acids reduce the production of TNF-α through the inhibition of tyrosine phosphorylation of cytoplasmic proteins and the inhibition of NF-κB activation in a peroxisome proliferator-activated receptor-independent pathway and after a rapid entry into the cytoplasm of macrophages. GPIs are considered toxins inducing irreversible damage in the host, and fatty acids produced in parallel by the parasite could reduce the immune response, thus favoring the persistence of parasite infection.

Purpose To evaluate whether posterior vitreous adhesion (PVA) contributes to retinal ischaemia in eyes suffering from central (CRVO) or branch retinal vein occlusion (BRVO). Methods Retrospective patient chart analysis of eyes with CRVO/BRVO receiving pars-plana vitrectomy (ppV). Prior to surgery fluorescence angiography was conducted to classify RVO as ischaemic or not. Results Sixty eyes were included, thereof 36 (60%)/24 (40%) with CRVO/BRVO. In the CRVO group, 17 (47%)/19 (53%) eyes were classified as ischaemic/non-ischaemic. Respective results for BRVO-affected eyes were 16 (67%)/8 (33%). PVA/posterior vitreous detachment (PVD) was found in 33 (92%)/3 (8%) eyes with CRVO and in 23 (96%)/1 (4%) patients suffering from BRVO. Value differences of PVA/PVD between ischaemic- and non-ischaemic-typed RVO failed statistical significance for both, CRVO (p = 0.095) and BRVO (p = 1.0). Conclusions Posterior vitreous adhesion had no impact on retinal ischaemia in this investigation. As an attached posterior vitreous cortex acts as a scaffold and thus significantly increases neovascularization (NV) development in ischaemic-typed RVO, a prospective study evaluating the effect of enzymatic vitreolysis is indicated.

Purpose: To demonstrate the cross-sectional morphology in crystalline retinopathy. Methods: A 24-year-old woman with Bietti's crystalline dystrophy (BCD) and bilaterally decreased vision and nyctalopia was examined by optical coherence tomography (OCT). Results: Fundus examination demonstrated numerous reflective, yellow-white crystalline deposits scattered throughout the posterior pole and midperipheral retina. Optical coherence tomography disclosed an abnormally level of high reflectivity in red to orange colours throughout the entire neuroretina, retinal pigment epithelium (RPE) and choroid. The RPE–choriocapillaris complex was thickened and hyper-reflective, corresponding with dense crystalline deposits. Conclusion: The observed uncommon hyper-reflectivity in BCD relates to the deposition of numerous infiltrates. In vivo investigations by OCT confirmed histological studies that a crystalline retinopathy corresponds with numerous infiltrates in the retina, RPE and choroid. The RPE and choroid have intensive hyper-reflection and may be the primary location of the disease.

Toxoplasma gondii is a ubiquitous parasitic protozoan, which causes congenital infectious diseases as well as severe encephalitis, a major cause of death among immune-deficient persons, such as AIDS patients. T. gondii is normally controlled by the immune system of healthy individuals, leading to an asymptomatic infection. T. gondii triggers early cytokine production, which, to a certain extent, protects the host against replication of tachyzoites, the infective form of the parasite. Glycosylphosphatidylinositols (GPIs) constitute a class of glycolipids that have various functions, the most fundamental being to link proteins to eucaryotic cell membranes. GPIs are involved in the pathogenicity of other protozoan parasites and are known to induce tumor necrosis factor-alpha (TNF alpha) production. We show that GPIs highly purified from T. gondii tachyzoites, as well as their core glycans, induce TNF alpha production in macrophages. A chemically synthesized GPI of T. gondii lacking its lipid moiety, GPIa, has the same effect as the natural GPIs, whereas a chemically synthesized molecule with dialkylglycerol instead of diacylglycerol as lipid moiety, GPIb, does not induce TNF alpha production. Moreover, GPIb inhibits the TNF alpha production induced by T. gondii GPI or by GPIa. The core glycan prepared from the two chemically synthesized molecules activates macrophages, showing that the lipid moiety may regulate signaling. Stimulation of macrophages with GPIs of T. gondii results in activation of the transcription factor NF-kappa B, which is inhibited by the chemically synthesized GPIb, suggesting the involvement of NF-kappa B in TNF alpha gene expression. Our results support the idea that T. gondii GPIs are bioactive factors that participate in the production of TNF alpha during toxoplasmal pathogenesis.

Hintergrund Bei der vitreoretinalen Chirurgie von Augen mit proliferativer diabetischer Vitreoretinopathie und ausgedehnten praretinalen Membranen ist es mit der herkommlichen drei-Port-Vitrektomie schwierig die festen zum Teil vaskularisierten praretinalen Membranen von der dunnen atrophen Netzhaut zu praparieren ohne grosere Netzhautdefekte zu setzen. Ein bimanuelles Arbeiten mit Pinzette und Glaskorperschere kann das praparieren erheblich erleichtern, erfordert bisher jedoch eine Endoillumination uber beleuchtete Instrumente oder des Einsatzes vom sog. MIS (Multiport-Illuminations-System). Beides ist kostenintensiv und nicht uberall verfugbar.

Background: Age-related macular degeneration (AMD) is a frequent cause of an irreversible loss of the ability to read. The non-exudative form of AMD has not been therapeutically approached in the past in contrast to the exudative form with choroidal neovascularizations (CNVs). Parafoveal laser coagulation can be applied, and in cases of subfoveal location a pars plana vitrectomy with subretinal resection of the CNV is possible. Material and Methods: Since 1995, we have operated 46 eyes of 45 patients with CNV developing from AMD. Patient ages ranged from 63 to 85 years (mean 71.8 years). Pre- and postoperatively we performed vision tests, fluorescence angiographies with sodium fluorescein and indocyanine green. Follow-up times ranged from 3 to 28 months (mean 12.3 months). Results: Pre-operative vision was 0.10 (range: hand movements to 0.4). Postoperative vision at the end of the follow-up period was 0.12 (range: hand movements to 0.4). Vision at the end of the follow-up was lower in 41%, unchanged in 20% and improved in 39%. In 43 eyes, a non-exudative form of AMD developed. Two eyes had a recurrent CNV, which was removed successfully with a second pars plana vitrectomy. Three patients developed a retinal detachment, which was successfully treated by pars plana vitrectomy, encircling buckle and gas tamponade. Conclusions: We still have to wait for the results of the photodynamic study trials and a randomized study of macular dislocation. Subretinal removal of the CNV by pars plana vitrectomy allows a stabilization of the visual function in most of our cases of AMD. This method inhibits the development of large pseudotumour-like scars. Postoperatively remaining pigment epithelial defects with choroidal atrophies however limit a visual rehabilitation so that reading vision can only be achieved in cases with good pre-operative vision. Long-term results of photodynamic therapy are still lacking and have to show its effectiveness over greater time spans.

Hintergrund Transparente okulare Gewebe wie Glaskorper und epiretinale Membranen sind wahrend einer Vitrektomie haufig schwierig abzugrenzen. Durch Anfarben mit ICG lassen sich diese Strukturen besser darstellen.

Background: Since introduction of brachytherapy using 106 ruthenium plaque therapy for treating malignant choroidal melanomas a number of comparative studies have shown that survival rates are equal between patients who underwent radiation or enucleation. When radiation treatment fails, the patient might be determined to choose removal of the tumor by pars plana vitrectomy. Patients and Methods: Between 1995 and 1998 a total number of 48 patients underwent 106 ruthenium plaque irradiation. In 9 patients tumor regression was not sufficient. Two of these nine patients decided explicitly against enuclation and choose to have the tumor removed from within the eye employing pars plana vitrectomy. Results: Intraoperatively, the previously radiated melanoma was easily removed with the vitrectomy cutter without significant bleeding. Postoperative recovery was without complications. Silicone oil removal was carried out in one patient after one year. Vision 9 months and 2.5 years after surgery was 0.2 and 0.02, respectively. The cosmetic results with parallel axis of the globes were very good and one patient gained binocular vision. No recurrent tumor growth was seen so far. Histologically, no mitotic figures were found. Conclusion: Malignant choroidal melanomas can be safely removed by pars plana vitrectomy with stable intraocular pressure. Previous radiation therapy alters the tumor, inducing fibrous tissue growth and necrosis of tumor cells. These tissue types are not prone to bleed when they are resected by the vitrectomy cutter. Long time studies have to elucidate the difference in survival rates between patients undergoing enucleation of the eye and patients who chose endoresection of the melanoma by pars plana vitrectomy.

BACKGROUND In the literature there is only a limited number of morphological reports on clinically diagnosed silicone oil associated keratopathy describing different histological changes. The purpose of the present study was to evaluate the most common histopathological features of this disorder. MATERIAL AND METHODS We reviewed the registry of the ophthalmopathological laboratory at the University of Marburg with respect to the following histopathological diagnoses: "bullous keratopathy", "endothelial-epithelial corneal decompensation", "band keratopathy" and "endothelial degeneration". These specimens were cross-checked with appropriate medical records. Eight specimens with a clinical diagnosis of silicone oil induced keratopathy were identified. All specimens were examined by light microscopy. RESULTS Histologically, a long-standing bullous keratopathy was seen in 5 out of 8 specimens. A descemetocele was present in two other corneas. One case displayed band keratopathy. A posterior collagenous layer (PCL) between Descemet's membrane and the endothelium was identified in 7 out of 8 specimens examined. This layer was of a fibrillar type in 2 corneal buttons and of a fibrocellular type in all remaining specimens with PCL. PCL was associated with endothelial cell loss and degeneration. The endothelial cell density varied between 0 and 5 cells per high power field. CONCLUSION Posterior collagenous layer associated with degenerating endothelium appears to be the most frequent histopathological feature in silicone oil induced keratopathy. The variety of PCL in this condition makes a firm histopathological diagnosis of "Silicone oil induced keratopathy" rather difficult.

BACKGROUND In patients with proliferative diabetic retinopathy rebleeding after pars plana vitrectomy is one of the most common complications. We tried to reduce the rate of that complication by using an air endotamponade. PATIENTS AND METHODS The following study is a retrospective comparison of 2 patient groups both after pars plana vitrectomy due to proliferative diabetic retinopathy. Group 1 was managed with air as endotamponade (n = 52, mean age 61.2 years), group 2 without any endotamponade (n = 40, mean age 59.4 years). Classification of the proliferative diabetic retinopathy as described by Kroll et al. [5] in both groups: 23 and 29 patients with stage A resp., 24 and 10 patients with stage B resp., 5 and 1 patient with stage C respectively. RESULTS 77% of group 1 patients had an increase os vision by mean of 4.8 vision steps, in 70% of the group 2 patients vision increased by mean of 7.2 vision steps. Complications in both groups as follows: Rebleeding within 14 days 15% vs. 33%, development of secondary glaucoma in 9.6% and 17.5% resp., revitrectomy within 14 days were necessary in 3.8% resp. 2.5% of the patients, later revitrectomy in 13.5% vs. 42.5% of all patients. SUMMARY Air endotamponade turned out to be appropriate to reduce the rate of postoperative vitreous rebleeding after pars plana vitrectomy due to proliferative diabetic retinopathy. We found no increase of secondary glaucoma or cataract.

Die expulsive Blutung stellt intra- und postoperativ eine, zwar seltene, aber gefurchtete Komplikation bei intraokularen Eingriffen dar. Durch eine gezielte Therapie lasst sich, neben der Bulbuserhaltung, auch ein orientierendes Sehvermogen aufrecht erhalten. In unserem Krankengut fanden sich in der Zeit von 1994 bis 1998 neun Augen (8 Patienten), die wegen expulsiver Blutungen behandelt werden mussten. Bei drei Augen kam es nach drucksenkender Operation in der postoperativen Hypotoniephase zu Aderhautblutungen. Bei 6 Augen ereignete sich die Blutung intraoperativ, bei 2 Augen wahrend einer Kataraktoperation und bei 4 Augen wahrend einer Pars-plana-Vitrektomie, bzw. Silikonolablassung. Eine mittlere und hohe Myopie fand sich bei 6 Augen (-5,0 dpt bis -19,0 dpt). Bei 5 Augen wurde im Rahmen einer Parsplana-Vitrektomie, mit Drainage der choroidalen Blutung, eine Silikonolendotamponade vorgenommen. Bei 4 Augen wurde die spontane Resorption abgewartet. Bei 5 von 8 Augen konnte das Silikonol abgelassen werden, bei 2 Augen kam es zur Schrumpfung des Auges. Bei 4 Augen stellte sich eine vollstandige spontane Resorption der Blutung ohne Drainage nach 4–12 Wochen ein. Infolge einer proliferativen Vitreo-Retinopathie wurde bei 5 Augen ein erneuter glaskorperchirurgischer Eingriff erforderlich. Die Sehscharfe lag praoperativ zwischen Lichtscheinwahrnehmung und 0,5 und betrug postoperativ zwischen Wahrnehmung von Handbewegungen und 0,2. Insbesondere hohe Myopien und Glaukome pradisponieren zu perioperativen, expulsiven Blutungen. Bei umschriebenen Aderhautblutungen kann die spontane Resorption abgewartet werden. Erst bei Auftreten einer proliferativen Vitreo-Retinophatie ist ein glaskorperchirurgischer Eingriff mit Silikonolendotamponade und Drainage der subretinalen Flussigkeit zu empfehlen. Die spontan auftretende expulsive Blutung wahrend eines vitreoretinalen Eingriffes sollte durch eine sofortige Silikonoltamponade aufgehalten werden. Bei grosflachiger Aderhautblutung lasst sich uber zentrale Sklerotomien die Blutung, wegen der Koagulation des Blutes, nur teilweise drainieren. Expulsive hemorrhage of the choroidea is a rare but feared complication occurring during or after intraocular procedures. A focused therapy can retain orientating vision together with a savour of the eye. In the time between 1994 and 1998 we had 9 eyes (from 8 patients) who were treated for expulsive bleedings (using silicone oil in 8 eyes). In three eyes choroidal bleeding occurred after surgeries lowering intraocular pressure during a postoperative phase of hypotony. In six eyes intraoperative bleeding occurred during cataract surgery and in 4 eyes during pars plana vitrectomy (PPV). Myopia was present in six eyes (ranging from -5 dpt to -19 dpt). In five eyes silicone oil was installed as an endotamponade following drainage of the choroidal bleeding. In four eyes we observed the spontaneous absorption of the bleeding. In five out of eight eyes silicone oil could be removed and in two eyes phthisis followed. Eyes which did not receive drainage of the choroidal bleeding showed a spontaneous absorption of the bleeding after 4 to 8 weeks. A second PPV was necessary in five eyes who developed a PVR. Preoperative vision ranged from light perception to 0.5 and was postoperatively between hand movement and 0.2. Especially myopic eyes and eyes with glaucoma run the highest risk for the development of perioperative expulsive bleedings. In regional choroidal bleedings a spontaneous absorption is possible. When a PVR is occurring second PPV with a silicone oil endotamponade and drainage of the subretinal fluid should be performed. If the expulsive bleeding occurs during vitreoretinal surgery then silicone oil tamponade should, if still possible, be installed. In large areal bleedings drainage of the bleeding over central sclerotomies is difficult and only possible in part due to choroidal blood clots. In summary the negative consequences of choroidal bleedings can be limited by PPV and silicone oil tamponade.

The surface antigens of the free-living protozoan Paramecium primaurelia belong to the family of glycosylphosphatidylinositol (GPtdIns)-anchored proteins. Using a cell-free system prepared from P. primaurelia, we have described the structure and biosynthetic pathway for GPtdIns glycolipids. The core glycans of the polar glycolipids are modified by a mannosyl phosphate side chain. The data suggest that the mannosyl phosphate side chain is added onto the core glycan in two steps. The first step involves the phosphorylation of the GPtdIns trimannosyl conserved core glycan via an ATP-dependent kinase, prior to the addition of the mannose linked to the phosphate group. We show that dolichol phosphate mannose is the donor of all mannose residues including the mannose linked to phosphate. Furthermore, we were able to identify in vitro a hydrophilic intermediate containing an additional N-acetylgalactosamine linked to the mannosyl phosphate side chain. The addition of this purified hydrophilic radiolabelled intermediate into the cell-free system leads to a loss of the GalNAc residue and its conversion to the penultimate intermediate having only mannosyl phosphate as a side chain. Together the data indicate that the GalNAc-containing intermediate is a transitional intermediate. We suggest that the GalNAc-containing intermediate is essential for biosynthesis and maturation of GPtdIns precursors. It is hypothesized that this oligosaccharide processing in the course of GPtdIns biosynthesis is required for the translocation of GPtdIns from the cytoplasmic side of the endoplasmic reticulum to the luminal side.

Purpose.To demonstrate keratoconus-like hydrops after laser in situ keratomileusis (LASIK) by optical coherence tomography (OCT).Patient and Methods.A 21-year-old man received uneventful bilateral LASIK. On slit lamp examination or corneal topography there were no signs of fruste keratoconus. The preoperative corneal thickness was 587-m OD and the calculated ablation for two treatments was 114-m. Uneventful LASIK with an optical zone of 7 mm and an ablation of 89-m OD, and an ablation of 73-m OS was performed. Three years postoperatively, he complained about progressive myopia and impaired vision OD. His VA was hand motion OD and 20/20 OS.Results.OCT and light microscopy revealed an anterior corneal steepening and acute keratoconus-like excessive edematous swelling.Conclusion.The cornea is mechanically weakened after LASIK by the lamellar cut and tissue subtraction. Although the advocated minimal residual stromal bed thickness is 250-m, it may not be adequate to prevent progressive keratoconus-like hydrops in the selected cases.

Background If sutures are used in the regular closure of sclerotomies a trauma to the bulbus can be inflicted and intraocular bleeding might result. Phases of intraocular hypotony accompany the intraoperative exchange of instruments. Like in no-stitch cataract surgery we employed this type of self-sealing wound closure in pars-plana vitrectomies. A less traumatizing technique yielding a tight and effective closure is an alternative to the conventional approach and results of our experiences are presented. Materials and methods A modified approach for sutureless sclerotomy closure was applied in 50 eyes (150 sclerotomies). A sclera-covered sclerotomy is performed after preparation of adequate scleral pouches in conventional positions. A minimal conjunctival peritomy allows at the end of surgery an electric cauterization, thus using no suture material in the whole course of vitrectomy. Results Sutureless vitrectomies can only be installed in the primary operation. However, re-operations on 3 eyes were possible in the same manner using the old sclerotomy sites up to 6 weeks after initial surgery. In 12 eyes the sclerotomy had to be covered with a single suture to obtain adequate wound closure. A repetitive change of instruments during the surgical procedure is possible with this technique and all types of intraocular instruments can be employed. Conclusions Self-sealing sclerotomies are a simple and atraumatic approach for wound closure in pars-plana vitrectomies and allow a control of intraocular pressure during surgery.

Background: The purpose of this study was to compare the regression of the tumor-distant exudative detachment that accompanies malignant melanoma with regression of the tumor as a result of ruthenium-106 irradiation.

Purpose: To describe the clinical features, retinal architecture and tomographic configuration of a pigmented epiretinal membrane on optical coherence tomography (OCT). Methods: A 52-year-old man presented during a routine examination with an asymptomatic, darkly pigmented, pre-retinal epiretinal membrane in his right eye. His best corrected visual acuity (BCVA) on Snellen charts was 20/25 in the right eye and 20/20 in the left. The patient complained of no visual symptoms or metamorphopsia. Results: In the fundus periphery there was a small, old, well pigmented retinal hole with pigmentation in its immediate vicinity, without signs of vitreal traction, which required no treatment. The foveal indentation was not apparent on OCT and a well demarcated hyperreflective band defined the pigmented epiretinal membranes (ERMs). Sequential fundus examination over a 2-year period demonstrated no functional or anatomical deterioration attributable to the disease. Conclusions: Pigmented ERM may have different cellular origins depending on the underlying pathology. Patients with pigmented ERM and full VA should be followed by sequential OCT.

BACKGROUND Postoperative complications concerning glaucoma filtering surgery (trabeculectomy, goniotrepanation) often include hypotonia that may lead to athalamia or choroidal detachment, which are difficult to handle. Cystic non filtering blebs are due to postinflammatory reactions, and may limit the success of filtering surgery. Aim of the study was to compare the success and the complications of a new operating technique, which will be described, with those of usual glaucoma filtering surgery. PATIENTS AND METHODS In 24 open angle glaucoma patients with mean intraocular pressure of 28.12 mm Hg (+/- 8.6) we performed external trabecular excision in 25 eyes since June 1997. Preoperative visual acuity and peak intraocular pressure were compared retrospectively in all eyes with the values of the first postoperative day, in 22 eyes after one month and in 17 eyes after 3 months. RESULTS Intraocular pressure measured between 0 mm Hg and 16 mm Hg on the first postoperative day (7.64 mm Hg +/- 4.3), after one month between 10 mm Hg and 30 mm Hg (17.81 mm Hg +/- 5.5) and after 3 months between 9 mm Hg and 26 mm Hg (15.29 mm Hg +/- 4.2). After 1 month 10 of 22 (45%) and after 3 months 7 of 17 eyes (42%) required antiglaucomatous drugs; 3 eyes needed gonitrepanation (2 weeks, 1 month, 3 months after ETE). Concerning postoperative complications, we observed 6 choroidal detachments, once erythrocoytes in the anterior chamber, twice hyphemata, twice inflammatory reaction in the anterior chamber, two flat anterior chambers and twice a positive seidel test. CONCLUSION Complications after ETE are similar to those after filtering surgery. Postoperative intraocular pressure dip after ETE in most eyes was not as pronounced as after goniotrepanation or trabeculectomy, and postoperative complications were all reversible. 45% of the eyes again needed antiglaucomatous drugs after one month and 42% after 3 months. A prospective long-term study has to verify the success respectively the complications of ETE.

International audience; Toxoplasma gondii and Plasmodium falciparum are apicomplexan parasites responsible for serious diseases in humans. Many studies have focused on the post-translational modifications (PTMs) found in the two protists including phosphorylation, acetylation or SUMOylation but only a few of these are concerned with the nuclear and cytosolic-specific glycosylation O-GlcNAcylation. O-GlcNAcylation is a highly dynamic PTM-regulated by the ON and OFF enzymes: O-GlcNAc transferase and O-GlcNAcase-that can compete with phosphorylation but its function remains unclear. In this work, we directly prove the O-GlcNAcylation in T. gondii using antibodies specifically directed against the modification and we strongly suggest its occurrence in P. falciparum. We found that the inducible 70 kDa-Heat Shock Protein is O-GlcNAcylated, or associated with an O-GlcNAc-partner, in T. gondii. Using anti-OGT antibodies we were able to detect the expression of the glycosyltransferase in T. gondii cultured both in human foreskin fibroblast and in Vero cells and report its putative sequence. For the first time the presence of O-GlcNAcylation is unequivocally shown in T. gondii and suspected in P. falciparum. Since the O-GlcNAcylation is implicated in many biological fundamental processes this study opens a new research track in the knowledge of apicomplexans' life cycle and pathogenic potential.

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Pan-American Association of Ophthalmology/Pan-American Ophthalmologic Foundation Deutsche Ophthalmologische Gesellschaft (DOG) Fehr Foundation, Marburg Purpose: To determine the incidence of rhegmatogenous retinal detachments (RD) after intravitreal injection in six high-volume centres.Methods: A consecutive, interventional, multicenter case series measured the incidence of RD in patients receiving intravitreal anti-VEGF. A total of 35 942 intravitreal anti-VEGF injections (the number of the injections determined by review of injection log books over a 3 year period) were performed under sterile conditions with the patient in a supine position. Injections were given 3.5-4.0 mm behind the limbus in a tunnelled fashion.Results: During 36 consecutive months, five RD were reported, between 2 and 6 days after the injection. of the affected eyes, four were myopic) 1.75 to) -5.5 dpt. the incidence rate of rhegmatogenous RD was 0.013% (5/35 942) per injection.Conclusions: the incidence of RD in our community setting was very low (1 per 7188 injections). All RD occurred during the early postoperative period. the risks of RD can be minimized by a careful injection technique. Univ Bonn, Dept Ophthalmol, D-53127 Bonn, Germany Univ Marburg, Dept Ophthalmol, Marburg, Germany Avastin Data Base Bonn, Bonn, Germany Triemli Hosp, Dept Ophthalmol, Zurich, Switzerland Universidade Federal de São Paulo, Vis Inst IPEPO, São Paulo, Brazil Asklepios Clin, Dept Ophthalmol, Hamburg, Germany Eye Clin, Duisburg, Germany Universidade Federal de São Paulo, Vis Inst IPEPO, São Paulo, Brazil Web of Science

To report the incidence of traumatic lens injuries as a complication of intravitreal injection at 5 high-volume academic centers.We determined in a retrospective, interventional, multicenter case series the consecutive number of the injections between January 5, 2006 and December 22, 2008 from the injection log books. All injections were performed under sterile conditions in a laying position, 3.5-4.0 mm behind the limbus in an oblique fashion. The main outcome measure was the incidence of lens damage.A total of 32,318 intravitreal injections were performed, and 3 cases of iatrogenic lens damage were reported during 36 consecutive months. All affected eyes were hyperopic. The overall incidence rate of lens injury was 0.006% (2/32,318) for intravitreal injections and 1 during a paracentesis 0.003 (1/32,318). The rate of phakic eyes determined was 67%, and thus, the incidence rate of lens damage in phakic eyes was 0.009% (2/21,653) (95% confidence interval, 0.00%-0.05%).Although there is no agreement regarding the proper intravitreal injection technique, the incidence of traumatic injuries to the crystalline lens was very low in a large series of injected patients in a community setting. The incidence compares favorably with that reported in clinical trials in which much more extensive preinjection preparation was mandated. A good preparation of the surgical incision with proper anesthesia and detailed information of the patient, as well as good anatomical skills of the treating physician, are mandatory to prevent this rare adverse event.

The aim of the present study was to investigate biochemical and morphological changes in rat lenses following long-term UV B irradiation. After an irradiation period of 156 days with follow-up documentation by means of Scheimpflug photography, section-related biochemical analyses of the lenses as well as histological investigations were performed. The video-based Scheimpflug photography (Zeiss SLC) again proved to be an excellent method for the documentation of the UV cataract induced in rats. The biochemical analyses provided indications to potential damaging mechanisms; the section-related technique used allows more precise analyses than the processing of whole lenses in a cataract type restricted to a certain layer, as is the case with UV B damage. The most prominent biochemical findings were a significant decrease in glyceraldehyde-3-phosphate dehydrogenase in the equatorial region in the group with the highest irradiation dosage and a decrease in lactate dehydrogenase in the nuclear region. The histological results reflect the local extent of the UV damage as well as its progression after a prolonged irradiation period.

International audience; N-Linked glycosylation is the most frequent modification of secreted proteins in eukaryotic cells that plays a crucial role in protein folding and trafficking. Mature N-glycans are sequentially processed in the endoplasmic reticulum and Golgi apparatus through a pathway highly conserved in most eukaryotic organisms. Here, we demonstrate that the obligate intracellular protozoan parasite Toxoplasma gondii independently transfers endogenous truncated as well as host-derived N-glycans onto its own proteins. Therefore, we propose that the apicomplexan parasite scavenges N-glycosylation intermediates from the host cells to compensate for the rapid evolution of its biosynthetic pathway, which is primarily devoted to modification of proteins with glycosylphosphatidylinositols rather than N-glycans.

Initial historical considerations to perform a pars plana vitrectomy were made for opaque vitreous cortex due to dense asteroid hyalosis or vitreous hemorrhages. However, current indications for vitreoretinal surgery include mainly vitrectomies in the presence of a clear vitreous, for example retinal detachments, epiretinal membranes or macular holes, thus visualization of the transparent vitreous gel facilitates proper vitreous removal.The transparent structure of the vitreous cortex as well as the thin epiretinal membrane may become visible during surgery by mild vitreous hemorrhages or intravitreous application of 0.05 ml crystalline triamcinolone acetonide. Eyes with a significant breakdown of the blood-retinal barrier accumulate intravenously applied vital dyes, for example fluorescein, in the vitreous cavity.Mild accidental intraoperative bleedings or intended injection of 0.05 ml autologous blood may help to stain transparent vitreous structures and visualize the remaining vitreous. Intravitreous triamcinolone crystals attach to the surface of the vitreous cortex, bursa premacularis or retina itself allowing better visualization of a controlled vitreous removal. A preoperative diagnostic fluorescein angiography in eyes with active uveitis or diabetic retinopathy may lead to a moderate accumulation of the dye in the vitreous cavity and greenish staining of the vitreous cortex at the vitreoretinal interface.A safe and complete removal of clear vitreous or transparent membranes may be achieved by the intraoperative application of autologous blood or triamcinolone. The preoperative systemic application of fluorescein greatly enhances the visualization of previously clear structures.

Background: Initial historical considerations to perform a pars plana vitrectomy were made for opaque vitreous cortex due to dense asteroid hyalosis or vitreous hemorrhages. However, current indicati

The use of vital dyes during vitrectomy allows easier removal of less recognizable structures like epiretinal membranes or the internal limiting membrane (ILM). In recent years, numerous studies have investigated the use of indocyanine green (ICG), trypan blue (Membrane Blue), triamcinolone, autologous blood and presently trityl dyes such as patent blue V (PBV, Blueron), crystal violet and brilliant blue G (BBG, Brilliant Peel) in chromovitrectomy. Reports on potential risks of these dyes, especially ICG, such as reduced visual acuity, possible visual field defects or alterations of the retinal pigment epithelium (RPE) limited their application. A systematic review of the literature up to July 2007 was performed using Medline (http://www.ncbi.nlm.nih.gov/ PubMed/) where we specifically searched for relevant information regarding the laboratory as well as clinical use of PB and BBG. To evaluate the effect of PB and BBG on the RPE, PB and BBG have been added to an in vitro model of the outer blood-retinal barrier to assess dye-associated barrier properties. Two concentrations of PB (2.4 and 1.2 mg/ml) and BBG (0.25 and 2.4 mg/ml) were investigated. To simulate in vivo conditions of a fluid-filled eye and an air-filled eye the dyes were added either to the culture medium or directly to the RPE cells where they remained for 2.5 min. To determine barrier properties, transepithelial resistance (TER) was measured at 3 days of follow-up. Ultrastructural integrity of RPE cells was evaluated by transmission electron microscopy. Following application of PB, barrier properties in the fluid- as well as in the air-filled eye showed only mild, transient and no significant decrease in TER. BBG did not cause a breakdown of the outer bloodretinal barrier at the concentration of 0.25 mg/ml in the model of the fluid-filled eye. The concentration of 2.4 mg/ml in the model of the fluid-filled eye as well as both concentrations in the model of the air-filled eye showed a minor decrease after 1.5 h, which was no longer observed after 24 h. Transmission electron microscopy did not show any dye-associated ultrastructural alterations to the RPE cells. In clinical use, PB showed only mild staining of epiretinal membranes and moderate staining of the ILM. Although BBG did not stain epiretinal membranes, it represents an appropriate candidate for the future, as BBG has a high affinity for the ILM. The use of trityl dyes in the posterior eye segment seems to be safe concerning damage to the RPE and its barrier function, especially when the dye is applied to the fluid-filled eye.

The effects of ultraviolet B (UV-B) irradiation on transmission of the rat cornea were studied in combination with or without naphthalene feeding. UV irradiation as well as naphthalene feeding caused a decrease in transmission in the wavelength region from 315 to 450 nm, UV irradiation being thereby the more hazardous influence. The combination of both noxae did not lead to a pronounced decrease as compared with UV irradiation alone. Although the histological findings of the eye lens suggest a syncataractogenic action of UV-B and naphthalene feeding, a corresponding effect could not be found by means of Scheimpflug photography. This could be possibly due to the alteration in corneal transmission properties following UV-B irradiation.

Closure of scleral perforations after trauma is frequently achieved by external suturing. Enlarged perforations towards the equator may require temporary removal of the external ocular muscle to visualise and fix the scleral wound.1 Nakashizuka et al. attached ‘ab interno’ a dislocated intraocular lens by introducing a 10–0 polypropylen loop, held by an intraocular forceps, into the vitreous cavity through a sclerotomy.2 Here, we describe the ‘ab interno’ intravitreal suturing of a large traumatic posterior scleral perforation at the posterior pole. A 34-year-old patient presented with a paracentral corneal perforation, collapse of the anterior chamber and severe vitreous haemorrhage OD. The patient’s visual acuity was light perception. The patient was treated in a two-step fashion according to Kuhn et al .3 A primary corneal wound closure and placement of a mild scleral buckle was immediately performed, with the application of topical and systemic corticosteroids. The following day, a computed tomography scan was ordered, which showed a …

Plasmodium falciparummalaria kills roughly 2.5 million people, mainly children, annually. Much of this mortality is thought to arise from the actions of a malarial toxin. This toxin, identified as glycosylphosphatidylinositol (GPI), is a major pathogenicity determinant in malaria. A malarial molecule, Pfj, labeled by [3H]glucosamine like the GPIs, was identified as a non-GPI molecule. Here we show that Pfj is able to down-regulate tumor necrosis factor alpha (TNF-α) production induced by the GPI ofP. falciparum. Mass spectrometry analysis showed that Pfj was not a single molecule but represented a number of molecules. Separation methods, such as cation-exchange chromatography and thin-layer chromatography, were used to isolate and identify the following four main fatty acids responsible for the inhibitory effect on TNF-α production: myristic, pentadecanoic, palmitic, and palmitoleic acids. This regulatory effect on cytokine production suggests that there is balanced bioactivity for the different categories of malarial lipids.

Purpose To describe transient structured visual hallucinations in a patient with vascular age-related macular degeneration (AMD), following an intravitreal Avastin-injection. Design Interventional case reports. Methods A fully alert 83-year-old woman with disciform scar right eye (OD) and occult choroidal neovascularization (CNV) left eye (OS) experienced a progressive visual loss to 20/800 OD and 20/400 OS. A coherent 84-year-old woman with occult CNV both eyes (OU) experienced decreased vision of 20/800 OU. After both patients gave informed consent, an uneventful intravitreal injection of 1.25 mg Avastin was performed in the left eyes. Results One day and three days after an uneventful intravitreal injection both patients experienced structured hallucinations including trees, faces, and water for approximately 15 to 30 minutes. Conclusions We report a typical symptoms of Charles-Bonnet syndrome (CBS) in patients with severe AMD after intravitreal Avastin-injections. The reduced retinal edema and realignment of the photoreceptors may promote the release phenomenon and trigger hallucinatory episodes.

Introduction: To determine the anatomical location and functional impairment in acute Purtscher’s retinopathy (PR). Material and Methods: A 15-year-old boy with acute PR was examined with optical coherence tomography (OCT) and microperimetry (MP). Results: His initial best corrected visual acuity was 20/30 OD and 20/80 OS, the MP demonstrated absolute scotomas in the central and peripapillary area of the cotton-wool spots. On the OCT, there was a hyporeflective area in the inner aspect of the retina, corresponding to white patches on funduscopy. After he had been treated with oral prednisolone 100 mg, his visual acuity improved to 20/20 OU within 4 weeks and there were no scotomas on the MP. The central retinal architecture returned to normal with no sub- or intraretinal fluid. Discussion: Cotton-wool spots in PR represent infarctions of the retinal nerve fiber layer. Deeper layers of the retina may also be involved, causing a breakdown of the inner blood-retina barrier with temporary intra- and subretinal edema.

Toxoplasma gondii is a ubiquitous parasite that infects nearly all warm-blooded animals. Developmental switching in T. gondii, from the virulent tachyzoite to the relatively quiescent bradyzoite stage, is responsible for the disease propagation after alteration of the immune status of the carrier. The redifferentiation event is characterized by an over expression of a tachyzoite specific set of glycosylphosphatidylinositol anchored surface antigens and free GPIs. T. gondii grown in animal cells uses two glycosylphosphatidylinositol precursors to anchor the parasite surface proteins. The first form has an N-acetylgalactosamine residue bound to a conserved three-mannosyl core glycan, while the second structure contains an additional terminal glucose linked to the N-acetylgalactosamine side branch. Sera from persons infected with T. gondii reacted only with the glucose-N-acetylgalactosamine-containing structure. Here we report that T. gondii cultured in human cells uses predominantly the N-acetylgalactosamine-containing structure to anchor the parasite surface antigens. On the other hand, glycosylphosphatidylinositol structures having an additional terminal glucose are found exclusively on the parasite cell surface as free glycolipids participating in the production of cytokines that are implicated in the pathogenesis of T. gondii. We also provide evidence that such free glycosylphosphatidylinositols are restricted mainly to the lipid microdomains in the parasite cell surface membrane and mostly associated with proteins involved in the parasite motility as well as invasion of the host cell.