Faster speed of onset of the depressive episode is associated with lower cytokine serum levels (IL-2, -4, -6, -10, TNF-α and IFN-γ) in patients with major depression

INTRODUCTION

Cytokines might play a key role in the pathophysiology of major depressive disorder (MDD). The speed of onset of depressive episodes has been discussed as an important clinical parameter in MDD. The aim of this study was to investigate a potential influence of the speed of onset of the depressive episode on cytokine serum levels.

METHOD

Serum level of the cytokines interleukin (IL)-2, IL-4, IL-6, IL-8, IL-10, tumor necrosis factor alpha (TNF-α), interferon-gamma (IFN-γ) granulocyte and monocyte colony stimulating factor (GM-CSF) were measured in a total of 92 patients with MDD that did not respond to at least one previous antidepressant treatment. Patients were retrospectively divided in two groups: Faster (≤4 weeks) and slower (>4 weeks) onset of the depressive episode defined as the time passing from the first depressive symptoms to a full-blown depressive episode by using information from a clinical interview.

RESULTS

We found significantly lower serum levels of IL-2, IL-4, IL-6, IL-10, TNF-α and IFN-γ in patients with a faster onset compared to patients with a slower onset of the depressive episodes. Furthermore, lower cytokine serum levels of IL-2, IL-8, IL-10 and IFN-γ were found in patients with a shorter duration (less than 6 months) compared to a longer duration (6-24 months) of the current depressive episode. This effect on cytokines was independent from the effect of the speed of onset of the depressive episode.

CONCLUSIONS

Patients with faster onset of the depressive episode might represent a biological subtype of MDD with lower serum levels of IL-2, IL-4, IL-6, IL-10, TNF-α and IFN-γ.

The challenge of combined exposure to multiple chemicals: scientific and regulatory approaches to protect human health

Every day we are exposed to low levels of hundreds of different manmade chemicals present for example in our food, consumer products and the air we breathe. Combined exposure to multiple chemicals can lead to adverse effects on human health or the ecosystem, even if single chemicals in the mixtures are below their individual safety thresholds. However, current safety assessment practice is primarily based on understanding the potential risk posed by single chemicals rather than their 'real life' combinations. In particular, while manufactured products such as pesticide formulations or cosmetic products are covered, unintentional mixtures which are coincidentally formed such as mixtures of contaminants in indoor air, are not consistently addressed. Their composition is often unknown and changes over time. The assessment of unintentional mixtures is therefore usually limited to specific legislative sectors only, such as pesticide residues in food.

Generally, methodologies to address chemical mixtures have been developed; however, there are still several data and methodological gaps to be addressed. New approach methodologies can support the filling of knowledge gaps on the toxicity and mode(s) of action of individual chemicals, to unravel links between chemical exposure and health effects. (Bio)Monitoring, modelling, and better data sharing will support the derivation of more realistic co-exposure scenarios. Considering the large number of possible combinations of chemicals in mixtures, prioritization is needed, so that actions first address mixtures of highest concern and chemicals that drive the mixture risk. As chemicals with different applications and regulated separately might lead to similar toxicological effects, it is important to consider chemical mixtures across legislative sectors.

This contribution to the workshop will summarise current challenges and ways forward in the risk assessment and risk management of mixtures for protecting public health.

Data for characterizing human exposure to chemicals and their contribution to human diseases: IPCHEM, HBM4EU

Human exposure to chemicals can occur via different sources and routes. Understanding the (combined) exposure to chemicals is often hampered by a lack of data or difficulties in sharing data. This was recognized in the Commission Communication on Chemical Mixtures (252, 2012) and the Information Platform on Chemical Monitoring (IPCHEM) was developed. The aim of IPCHEM is to support a coordinated approach for collecting, storing, sharing and assessing data on the occurrence of chemicals and chemical mixtures in humans and the environment. IPCHEM covers four thematic areas to support a holistic approach to exposure assessment, including human biomonitoring, environmental monitoring, food and feed monitoring and indoor air and consumer products. The shared occurrence data support exposure assessment, the identification of sources and hot spots, the analysis of time trends and can also support the evaluation of the impact of regulatory measures to restrict exposure to specific chemicals. In particular, human biomonitoring data can provide insights into internal combined exposure, integrating across different exposure sources and routes. The ongoing EU funded project HBM4EU generates and uses human biomonitoring to assess human exposure to chemicals in Europe, to better understand the associated health impacts and to improve chemical risk assessment. Associations between chemical exposures and development of disease can be further supported using toxicological/mechanistic information to establish causal links. The presentation will focus on relevant types and sources of data available to support health impact assessments of chemical exposure.

Cytokine serum levels remain unchanged during lithium augmentation of antidepressants in major depression

Lithium augmentation (LA) of antidepressants is a first-line therapy in treatment-resistant depression. Immunomodulatory effects of lithium have been described. The cytokine hypothesis of depression postulates that cytokines play a key role in the pathophysiology of depression. Concordantly, it has been shown that proinflammatory cytokine serum levels decrease during antidepressant treatment. The aim of this study was to investigate changes in cytokine serum levels during LA. Serum concentrations of the cytokines interleukin (IL)-2, IL-4, IL-6, IL-8, IL-10, tumour necrosis factor alpha, interferon-gamma, granulocyte and monocyte colony stimulating factor were measured in a total of 95 acutely depressed patients before and after four weeks of LA. Changes in cytokine levels were corrected for the confounding factors severity of depression, treatment response, lithium serum level, gender, age and body mass index in a linear mixed-model analysis. We did not find a significant change in any of the measured cytokine serum levels during LA (p > 0.05). In conclusion, our study does not support the role of cytokine serum levels as a state marker in treatment of depression with LA.

Ghrelin Serum Concentrations Are Associated with Treatment Response During Lithium Augmentation of Antidepressants

BACKGROUND

Lithium augmentation of antidepressants is an effective strategy in treatment-resistant depression. The proteohormone ghrelin is thought to be involved in the pathophysiology of depression. The purpose of this study was to investigate the association of treatment response with the course of ghrelin levels during lithium augmentation.

METHOD

Ghrelin serum concentrations and severity of depression were measured in 85 acute depressive patients before and after 4 weeks of lithium augmentation.

RESULTS

In a linear mixed model analysis, we found a significant effect of response*time interaction (F1.81=9.48; P=.0028): under treatment, ghrelin levels increased in nonresponders and slightly decreased in responders to lithium augmentation. The covariate female gender had a significant positive effect (F1.83=4.69; P=.033), whereas time, response, appetite, and body mass index (kg/m2) did not show any significant effect on ghrelin levels (P>.05).

CONCLUSION

This is the first study showing that the course of ghrelin levels separates responders and nonresponders to lithium augmentation. Present results support the hypothesis that ghrelin serum concentrations might be involved in response to pharmacological treatment of depression.

[Prognosis and treatment of macular bleeding in neovascular age-related macular degeneration]

Macular bleeding is associated with an acute loss of visual function and is frequently a complication of neovascular age-related macular degeneration. Blood degradation products can lead to permanent retinal neuronal damage over time. The extent of the bleeding is correlated to the coagulation status of the patient. The treatment strategy depends on the age, size and exact location of the bleeding. The spectrum of therapeutic options ranges from watchful waiting to large scale vitrectomy with removal of subretinal mass bleeding.

Leptin serum concentrations are associated with weight gain during lithium augmentation

BACKGROUND

Meta-analytical data show lithium augmentation (LA) as an effective treatment strategy in major depression. Weight-gain is a common side effect of LA. The proteohormone leptin is discussed to be involved in the pathophysiology of weight gain induced by psychopharmacological treatment. The purpose of our study was to investigate the association of leptin and body mass index (BMI) during LA in a prospective cohort study.

METHODS

Leptin serum concentrations and body mass index (BMI) were measured in a total of 89 acute depressive patients before and then after four weeks of LA.

RESULTS

In a linear mixed model analysis the following variables had a significant positive effect on BMI: time (equal with "treatment effect of LA"; F1.83=6.05; p=0.016) and leptin (F1.111=13.83; p=0.0003) as well as the covariates male gender (F1.89=5.08; p=0.027) and adiposity (F1.85=105.13; p<0.0001).

LIMITATIONS

If the reported effect of leptin on BMI is specific to LA remains unclear without a control group.

CONCLUSION

Leptin signalling might be involved in lithium-induced weight-gain.

[Retinal Arterial Macroaneurysms (RAM)--pathology, differenzial diagnoses, and therapy]

Retinal arterial macroaneurysms (RAM) are unilateral, solitary, acquired saccular or fusiform dilatations of the large arterioles of the retina, usually within the first three orders of bifurcation. They are associated with systemic vascular conditions such as hypertension and arteriosclerotic disease and occur most commonly in elderly women. Cases of simple RAM are predominated by the vascular ectasia. These macroaneurysms regress without treatment and without causing decreased visual acuity and will usually remain undetected. Complex RAM often go along with vision loss due to haemorrhage or oedema affecting the macula. Poor visual outcome may occur secondary to foveal exudates and subfoveal haemorrhage, the latter appear as pre-retinal, intra-, and subretinal haemorrhage. This overview discusses conservative and surgical therapeutic options for complex cases.

[Trauma-associated juvenile rhegmatogenous retinal detachment]

BACKGROUND

Rhegmatogenous retinal detachments (RRD) in children and adolescents are uncommon and present about 3-5 % of all retinal detachments. Etiology, pathogenesis and therapy differ significantly from adults. The current study addresses juvenile RRD after trauma to contribute to the limited knowledge about this condition.

PATIENTS/MATERIAL AND METHODS

The current study includes 27 eyes of 25 patients aged up to 18 years that were operated on between 2000 and 2012. They presented 42.4 % of all RRD of that age group. We analyzed the following parameters: demographic data, retinal detachment characteristics, surgical techniques and outcomes.

RESULTS

Mean age was 15,3 years and 77 % were boys. Retinal detachment occurred between 3 days and 11 years after trauma (median: 3,5 months). Two thirds of RRDs were classified as acute, the remainder showed symptoms of chronicity, e.g. pigment demarcation and subretinal strands or PVR. The macula was detached in 81,5 %. Retinal dialysis was the most common type of break (44,8), followed by giant retinal tears (18,5 %). In 3 out of 5 eyes with severe PVR due to self-aggressive behavior a causative retinal defect was not identified. Episcleral buckling surgery was the preferred method in any case that deemed manageable with a segmental sponge or encircling band (14 eyes). Primary vitrectomy was performed in more complex retinal detachments (13 eyes), and most of them had silicone oil tamponade. Primary reattachment was achieved in 83 % in the buckling group and 80 % in the vitrectomy group (3 eyes with self-harm excluded). Finally, all eyes had attached retinas. Postoperatively, visual acuity improved or remained stable in successfully treated eyes. Late complications in the vitrectomy group were cataract development in half of the phakic eyes.

CONCLUSIONS

Retinal dialysis and giant retinal tears are the most frequent retinal lesions in posttraumatic RRD. Delayed diagnosis is a common problem, as most of the cases preset with macula-off detachments and clinical signs of chronic RRD. A conventional approach to traumatic RRD using scleral buckling techniques is recommended whenever possible. Differently from adults, strong vitreoretinal adhesions are present and the vitreous is rarely detached which makes a complete vitrectomy challenging. Furthermore there is a significant risk of postoperative cataract despite of the young age. However, cases with giant retinal tear and complex detachments due to PVR require vitrectomy maneuvers, usually with the use of silicone oil. A special subgroup presents PVR-detachments due to chronic auto-aggressive behavior of disabled young patients. Despite of extreme vitreoretinal maneuvers used, those eyes might be inoperable or late failures due to chronic aggressive PVR. On the whole, delayed diagnosis and advanced RRD limit final vision. However, after successful surgery, approximately half of the eyes improve, many retain vision. As preserving vision in young patients is of great impact for their whole lifespan, any attempt should be made to achieve a stable retinal situation.

[Subretinal hemorrhage. Natural course and staging]

Subretinal hemorrhages are a complication of various diseases which arise from the choroidal or retinal circulation. Most commonly the underlying pathology is a choroidal neovascular membrane (CNV) especially in patients with age-related macular degeneration (AMD). Less common ocular diseases are those with non-AMD-related CNV and retinal arterial macroaneurysms (RAM). Case studies have demonstrated a poor prognosis, however, a significant portion have favorable outcomes. Therefore, therapeutic decision-making is difficult. As a major difficulty in comparing different treatment modalities for submacular hemorrhages is the lack of a standardized definition of the extent of the hemorrhage. A classification for AMD-related subretinal hemorrhages including size, thickness and intraretinal location is suggested.

[Visual development of postoperative persistent macular holes with and without surgical revision]

BACKGROUND

Postoperative persistent macular holes after vitrectomy are a rare, but typical phenomenon. Without further surgical intervention the visual acuity remains unchanged. There are no generally accepted treatment recommendations for these cases. We report on 23 cases with postoperative persistent macular holes with and without further surgical treatment and analyzed the clinical outcome.

METHODS

A retrospective case control study was performed and visual acuity and anatomic status of the macular holes were analysed in 23 cases with a persistent macular hole after previous vitrectomy. Seven patients refused further surgical treatment (group 1) and were used as a control group. Three patients received a second intravitreal gas tamponade without further surgical manipulation (group 2). A vitrectomy revision with endotamponade was performed in 13 eyes (group 3). Additional autologous blood on the macular hole was used in 4 cases and adjuvant ICG-assisted peeling of the inner limiting membrane around the macular hole was performed in another 9 cases.

RESULTS

The eyes of group 1 showed a statistically not significant (p = 0.56) change of the median LogMAR visual acuity from 1.3 (range 0.7 - 1.4) to 1.2 (range 0.3 - 2.0) over a median follow-up of 11.8 months. No eye in group 2 developed a closure of the macular hole. After a median follow-up of 3.6 months the LogMAR visual acuity dropped statistically not significantly from 0.7 (range 0.7 - 1.9 to 1.0 (range 0.8 - 1.0; p = 0.5). 61 % of eyes showed a closure of the macular hole after a second vitrectomy (group 3). Eight out of 16 retreated eyes had finally a persistent macular hole. In these cases median LogMAR visual acuity decreased insignificantly from 1.0 (range 0.7 - 1.4) to 1.1 (range 0.7 - 1.4; p = 0.27) during a median follow-up of 13.7 months. In 8 eyes with a finally closed macular hole median LogMAR visual acuity increased statistically significantly from 0.8 (rage 0.4 - 1.3) to 0.35 (range 0.04 - 0.9; p = 0.016) after a median follow-up of 8.1 months.

CONCLUSION

Surgical revision of postoperative persistent macular holes using vitrectomy and endotamponade showed a success rate of 61 %. Eyes that had unsuccessful subsequent surgery had a slight decay of the visual acuity during the follow-up that was similar to that of eyes without further surgical treatment. In contrast, the final closure of the macular hole after a second surgery was associated with a significantly increased visual acuity.

Treatment of central retinal vein occlusion by radial optic neurotomy in 107 cases

BACKGROUND

To evaluate the potential role of radial optic neurotomy (RON), a new surgical technique has been recently proposed for treating central retinal vein occlusion (CRVO). It is hypothesized that CRVO constitutes a neurovascular compartment syndrome at the site of the lamina cribrosa, which can be alleviated by performing a radial incision at the nasal part of the optic nerve head, relaxing the cribriform plate and the adjacent sclera.

METHODS

One hundred and seven patients were treated with RON for CRVO at five collaborating ophthalmologic centers. All patients were evaluated by a standardized protocol. For analysis of the angiographic and fundus findings, reference images were used. Intraoperative and postoperative complications were reviewed.

RESULTS

On 55 right and 52 left eyes of 107 patients (55.6% male, 44.4% female) with a median age of 68 years (range 21-91 years), RON was performed. The median follow-up time was 6 months (range 1-24 months). The median preoperative visual acuity (VA) was 0.05 (logMAR 1.3), increasing to a median postoperative VA of 0.08 (logMAR 1.1). Patients with an interval of more than 90 days between RON and onset of CRVO showed no significant change in VA at the 6-month follow-up. Severe peripapillary swelling of the optic nerve head prior to RON resulted in an average increase of 4.2 lines in VA at the 6-month follow-up. Angiographic findings of shunt vessels were seen in 18/30 cases after 12 months and were accompanied by an average improvement of VA of six lines. Visual field tests showed various defects in 86.8% of all cases. In one patient an iatrogenic injury of the central retinal artery occurred (0.9%).

CONCLUSION

Despite the potential risk of visual field defects, RON seems to be a quite safe procedure. The majority of patients showed rapid normalization of the morphologic fundus findings, with an improvement in VA uncommon for the natural history of CRVO. No significant change in VA was seen in patients with an interval of more than 90 days between the onset of CRVO and RON. A prospective study is warranted for further investigation.

Verteporfin photodynamic therapy induced apoptosis in choroidal neovascular membranes

AIM

To evaluate the impact of verteporfin photodynamic therapy (PDT) on the induction of apoptosis in choroidal neovascular membranes (CNV) secondary to age related macular degeneration.

METHODS

Retrospective review of 22 surgically excised CNV. 12 of these patients had been treated with PDT 3-146 days previously. Apoptotic cells were detected with the TUNEL technique and compared to the expression of CD34 (endothelial cells, EC), CD105 (activated endothelial cells), Ki-67 (proliferation marker), and cytokeratin18 (retinal pigment epithelial cells, RPE).

RESULTS

CNV excised 3 days after PDT were characterised both by collapsed and patent vessels. The EC displayed a statistical significant positive TUNEL reaction when compared to the remaining treated CNV (p < 0.001) and untreated CNV (P = 0.002). The proliferative activity was reduced. CNV excised 1-5 months after PDT displayed a patent vascularisation and high proliferative activity. All membranes either treated or untreated disclosed only sporadic TUNEL positive cells within the stroma and the RPE.

CONCLUSIONS

Verteporfin PDT leads to selective and effective damage of EC within CNV. Both patent and occluded vessels were lined by apoptotic EC. This finding and the increased expression of proliferation marker at later time points suggest that revascularisation after PDT is caused by angiogenesis rather than recanalisation.

Comparative in vivo analysis of the sealing ability of three endodontic sealers in post-prepared root canals

AIM

To compare the sealing ability of the endodontic sealers AH Plus, Sealer 26 and Endofill in premolar teeth of dogs exposed to the oral cavity after post-preparation.

METHODOLOGY

Forty teeth with two canals each underwent root canal cleaning and shaping. Before filling, the canals were randomly distributed into three groups according to the sealer to be used: Group 1 - AH Plus; Group 2 - Sealer 26; and Group 3 - Endofill (Dentsply, Indústria e Comércio Ltda.). Immediately after filling, the gutta percha and sealer were partially removed from the canals, leaving material only in the apical third of the root. The teeth were temporarily sealed with glass ionomer sealer for 72 h to ensure setting. The coronal seal was then removed and the canals were exposed to the oral cavity for 45 days. The animals were euthanased and their mandibles and maxillae were removed. After abundant irrigation with distilled water, the canals were dried and filled with India ink. The teeth were sealed again for 96 h before extraction. The roots of the extracted premolars were separated and stored in labelled test tubes. The roots were cleared and the extent of dye penetration was measured with a 20x stereoscopic magnifying lens.

RESULTS

Statistical analysis revealed that there were significant differences between the sealers studied (P < 0.001). Means for the extent of dye penetration for AH Plus, Endofill and Sealer 26 were, respectively, 0.13, 2.27 and 3.08 mm.

CONCLUSIONS

After 45 days exposure to the oral cavity, none of the sealers was capable of preventing leakage and coronal dye penetration. There were significant differences between the sealers studied, in terms of mean dye penetration.

The vascular component of proliferative vitreoretinopathy membranes: an immunohistochemical and ultrastructural study

BACKGROUND

The basic cellular components of proliferative vitreoretinopathy (PVR) membranes are well studied. Endothelial cells have also been documented. The importance of the vascular element in PVR has received little attention, as vascular components are clinically inapparent. The aim of this study was to obtain a better characterization and quantification of occurrence of the vascular component.

METHODS

Serial sections of surgically excised PVR membranes were examined with Lectin histochemistry (25 membranes with ulex europaeus agglutinin I [UEA I] and rhicinus communis agglutinin I [RCA I]), immunohistochemistry for von Willebrand factor (31 membranes), and electron microscopy.

RESULTS

Vascular endothelial cells were identified by visualization of UEA I and RCA I binding sites or by marking for von Willebrand factor. A total of 28.6% of the PVR membranes showed a vascular component. Vascular components consisted mostly of capillary-sized vessels; larger vessels were rarely found. Ultrastructurally, most vascular elements were found to be capillaries of the nonfenestrated type. Membranes from eyes that underwent PVR surgery with silicone oil tamponade showed vascular components less frequently (18.5%) than did membranes from eyes without silicone oil (43.8%).

Peripheral visual field loss after vitreous surgery for macular holes

BACKGROUND

Vitreous surgery for Idiopathic macular holes can result in both anatomic closure of the hole and visual improvement. In some patients even normal visual acuity is achieved. Postoperative visual field loss is a newly recognized complication. This prospective study evaluates the frequency and significance of scotomas after vitrectomy with gas tamponade for stage I-IV macular holes.

METHODS

Over a period of 10 months, a consecutive series of 30 patients and 31 eyes with macular holes underwent pre- and postoperative automatic perimetry (Octopus 07, 70 degrees) and macular perimetry (Octopus M1, 24 degrees) to characterize the pattern of visual field defects after vitrectomy with gas tamponade. Success rates were evaluated and complications were analyzed.

RESULTS

Anatomic success after one surgical procedure was achieved in 85% of cases, visual improvement in 58%. Some 70.1% of patients had peripheral scotomas postoperatively; some of these were highly symptomatic and others were detected by visual field testing only. The most consistently affected areas were the temporal and lower periphery of the visual field. The central visual field, however, was not disturbed.

CONCLUSION

Visual field loss after otherwise successful surgery for macular holes is an unexpectedly frequent and serious complication. The authors discuss various factors that may contribute to the postoperative scotomas. From the localization of the scotomas it seems most likely that they are caused by the persistent pressure of the gas bubble on the peripheral retina. Further investigations are necessary to confirm this hypothesis, and ways must be found to avoid this complication in order to be able to proceed with this otherwise promising new indication group for vitreous surgery.

[Endotamponade with silicon oil in severe proliferative retinopathy with attached retina]

Silicone oil as endotamponade in cases with attached retina is only indicated in a few very selected cases. These are cases with a high risk of intravitreal hemorrhage and a need for quick visual rehabilitation. We examined 23 patients, who had undergone pars plana vitrectomy and silicone oil filling. All patients were diabetics with proliferative retinopathy and recurrent intravitreal hemorrhage. In 14 cases it was the only eye; 11 eyes previously had a vitrectomy. We analyzed these cases for visual acuity, rubeosis, bleeding tendency, reproliferations, cataract development and glaucoma. The follow-up time was 32 months. In 22 of 23 eyes quick visual rehabilitation was achieved, and the patients had at least ambulatory vision within the first week. In one case poor visual acuity was due to exudative maculopathy. No relevant bleeding occurred. In 14 of 16 phacic patients we observed a cataract. Seven patients developed glaucoma, which was due to neovascularization in 5 cases. It was successfully treated in all cases and no visual loss occurred. In 5 cases we observed a peripheral traction retinal detachment, in one case a traction retinal detachment at the posterior pole. In selected cases silicone oil can prevent recurrent intravitreal hemorrhage, allowing rapid visual recovery. Considering the complications, the silicone oil should be removed as soon as possible.

Ten allelic apolipoprotein[a] 5' flanking fragments exhibit comparable promoter activities in HepG2 cells

Plasma levels of the atherogenic lipoprotein[a] represent a quantitative genetic trait that is primarily controlled by the polymorphic apolipoprotein[a] locus on chromosome 6q. The more than 1000-fold variation in lipoprotein[a] plasma levels is explained to a large extent by a remarkable size polymorphism of the apolipoprotein[a] gene which is translated into apolipoprotein[a] isoforms and by unidentified sequence variation in apo[a]. In a recent report, sequence variation in a 1.5 kb fragment from the 5' flanking region of the apolipoprotein[a] gene was associated with different promoter activities, which led to the suggestion that transcriptional control of the apolipoprotein[a] gene might contribute significantly to lipoprotein[a] plasma levels. We have used a reporter gene assay to compare the promoter activities of these 1.5 kb fragments which were cloned from ten well-characterized apolipoprotein[a] alleles. These ten allelic apolipoprotein[a] fragments revealed, despite the same sequence variation as previously reported, comparable and relatively weak promoter activities in HepG2 hepatocarcinoma cells. Promoter activity for the same fragment in non-liver cells and the identification of a liver cell-specific DNaseI hypersensitive site 3 kb upstream from the ATG start codon suggest that longer fragments must be used in order to analyze the transcriptional regulation of the apolipoprotein[a] gene.

Sequence polymorphisms in the apo(a) gene associated with specific levels of Lp(a) in plasma

Most of the interindividual variations in plasma levels of lipoprotein(a) [Lp(a)] can be attributed to sequence differences linked to the apolipoprotein(a) [apo(a)] locus. Plasma levels of Lp(a) tend to be inversely related to the number of kringle 4 (K4)-encoding sequences in the apo(a) gene, but there are several exceptions to this general trend. Other aspects of the apo(a) gene, in addition to the number of K4 repeats, affect plasma levels of Lp(a). To identify sequences in the apo(a) gene that contribute to plasma Lp(a) levels, we characterized the relationship between a length polymorphism [(TTTTA)n] located 1.3 kb 5' of the first exon of the apo(a) gene, the number of K4 repeats in the gene, and the plasma levels of Lp(a). There was significant linkage disequilibrium between the number of TTTTA repeats and the number of K4 repeats. All of the apo(a) alleles with 11 TTTTA repeats contained fewer than 24 K4 repeats and were paradoxically associated with low plasma Lp(a) levels (< or = mg/dl). To determine whether this association was due to the effect of the 11 TTTTA copies on apo(a) gene transcription, we measured the ability of fragments containing 11 or eight TTTTA repeats to promote transcription when introduced into cultured human hepatocarcinoma cells. No difference was found in the transcriptional activity of the two fragments. The TTTTA repeat constitutes the first sequence polymorphism at the apo(a) locus, other than the number of K4 repeats, which is associated with plasma concentrations of Lp(a).

[Proliferative retinopathy in chronic myeloid leukemia]

BACKGROUND

In 50% of patients with acute and chronic myelocytic leukemia retinal alterations occur which are similar to those of nonproliferative diabetic retinopathy or hypertensive retinopathy. Retinal neovascularizations, however, are rarely seen and only found in patients with the chronic disease.

PATIENTS AND METHODS

We report on the clinical course of three patients with advanced stage of proliferative retinopathy in CML. In two patients, the diagnosis of CML was established after ocular involvement. Therapy was planned according to the principles, which have proven effective in other vasoproliferative retinopathies. Eyes with neovascular changes were only treated by panretinal scatter photocoagulation of the avascular zones. In the cases with complications like vitreous hemorrhage and traction retinal detachment, vitreoretinal surgery was performed.

RESULTS

Using this therapeutic principles in 4 of 6 eyes a visual acuity > 0.7 could be preserved. In three eyes impending macular involvement by traction retinal detachment was prevented.

CONCLUSION

The therapeutic approach, which is valid for proliferative retinopathies of various etiology is also beneficial for ocular complications in CML.

[Clinical heterogeneity of non-Hodgkin's lymphoma of the eye with extraocular manifestations]

Primary, ocular Non-Hodgkin lymphoma is a multicentric disease. The prognosis is mostly determined by involvement of the central nervous system and/or visceral organs. Since ocular symptoms often precede accompanying manifestations and since the eye is easily accessible to diagnostic measures, the ophthalmological diagnosis is essential for early detection and treatment of this complex disease, which has a poor prognosis. To illustrate the extraordinary heterogeneity of the clinical symptoms, four case reports have been selected which demonstrate various ocular symptoms and extraocular localizations. The ophthalmological variability ranges from typical uveitis to retinitis and vasculitis with varying symptoms during the progression of the disease. Completely different extraocular features were induced by long-standing, local infiltrates within basal ganglia, a diffuse infiltration of the brain leading to an acute increase in intracranial pressure, a peripheral tumour within the spinal channel or massive infiltrates of liver, lung and kidneys. Lack of pathognomonic features, high clinical variability and the limited value of imaging techniques and histopathological measures often lead to serious delays in diagnosis.

The photoreceptor cells and retinal pigment epithelium of normal and diseased human retinas express different glycoconjugates

The photoreceptor cells and retinal pigment epithelium (RPE) represent a highly differentiated functional unit that may be disrupted in a variety of retinal diseases. We studied the localization and distribution of carbohydrate residues in normal and pathologically altered human retinas using lectin histochemical techniques. Paraffin-embedded tissue sections were investigated for binding sites with six lectins: concanavalin A (Con A), wheat germ agglutinin (WGA), Ricinus communis agglutinin (RCA I), peanut agglutinin (PNA), soybean agglutinin (SBA), and Ulex europaeus agglutinin (UEA I). Lectin binding to both the photoreceptor segments and the RPE was observed in the normal retina with Con A, WGA, RCA I, and PNA, particularly to the distal outer segments and to the apical portion of RPE cells. Disturbance of the photoreceptor-RPE cell complex occurred in eyes with damaged outer retinal layers and those with retinal detachment. Photoreceptor cells with a varying degree of inner and outer segment degeneration revealed an overall decrease in lectin-binding sites as well as alterations in their cellular topography. Reactive and proliferating RPE, however, showed a markedly increased reaction intensity for Con A, WGA, RCA I, and PNA as well as additional binding sites for SBA in macrophage-like variants. The data are taken as evidence that in the normal retina, a characteristic location and distribution of lectin-binding sites as well as correspondences in certain cellular glycoproteins of both photoreceptor cells and the RPE are indicative of structural and functional integrity. Disturbance of the photoreceptor-RPE cell complex is accompanied by changes in the expression of lectin-binding sites on both cell types.

Retinal lesions experimentally produced by intravitreal ultrasound

Currently, vitreous surgical techniques combined with phakoemulsification are an established procedure for the removal of luxated natural lenses or dislocated lenticular material. This has proven to be a safe procedure, but occasionally retinal lesions have been inadvertently created. We describe the ophthalmoscopic and morphologic features of ultrasonically induced retinal lesions in rabbit eyes using a similar technique. The retina was treated directly using a conventional ultrasound tip for pars plana lensectomy (Fragmatome). Ophthalmoscopically slight lesions corresponded to an area of retinal whitening. More severe lesions showed a destruction of the inner retina and created a retinal break. Extensive effects also involved the choroid and led to a retinal defect with rupture of choroidal vessels and heavy bleeding into the vitreous cavity. Histologic evaluation showed that the acoustic energy primarily led to damage of the outer retina, later involving the inner retina and the choroid as well.

Lectin binding pattern in human retinal pigment epithelium

A comparative lectin histochemical study of human retinal pigment epithelium (RPE) was performed to investigate the lectin binding pattern of normal, reactive and proliferating RPE. Normal RPE with attached sensory retina was found to bind the lectins Con A, WGA, PNA and RCA I. Reactive and proliferating RPE in retinal detachment and in photocoagulation scars revealed the same lectin binding pattern although its cellular topography changed. RPE-macrophages showed an additional reaction with SBA. In periretinal membranes of human PVR the typical lectin binding pattern of Con A, WGA, PNA and RCA I was found in pigmented and in a subpopulation of non-pigmented cells, suggesting that these lectin-positive elements were of RPE-origin. Additionally, single pigmented cells positive for SBA were found indicating macrophage differentiation. Thus lectin histochemistry provides a tool for cytochemical identification of RPE and its morphologic variants by revealing a specific combination of sugar-binding sites.

[Fluorescein angiography findings after retinotomy and retinectomy]

Drainage-retinotomies and relaxing retinectomies are helpful techniques in extreme vitreoretinal surgery. They have become established as a surgical instrument, but their possible pathophysiologic effects on the retina, pigment epithelium and choroid have not been investigated as yet. 30 Patients with retinotomies or retinectomies after vitrectomy with silicone oil filling for advanced proliferative vitreoretinopathy were studied angiographically. Fluorescein angiographic findings revealed 1. a predominant effect of endophotocoagulation in the area of the retinotomy/retinectomy with occlusion of the choriocapillaris and hyperpigmentation and window effects of the retinal pigment epithelium, but sometimes there was a localized traction effect with retinal and choroidal folds, 2. that retinal perfusion is unaffected in untreated and coagulated areas without evidence for a breakdown of the blood-retina-barrier or retinal ischemia, 3. an intact blood-retinal-barrier in areas of uncovered retinal pigment epithelium, 4. no evidence for significant reproliferations in the areas of retinotomies and retinectomies, 5. choroidal neovascular membranes which may occur postoperatively at the retinotomy site probably as a complication for intraoperative injury of Bruch's membrane, 6. a cystoid macular edema, an optic atrophy, pigment-fallout, depigmented tracks and choroidal folds as unspecific findings post retinal detachment surgery. The angiographic data support the clinical impression, that retinotomies and retinectomies performed in otherwise untreatable cases cause no significant damage in the attached retina.

[Corneal Ascher ring. A ring-shaped stromal corneal opacity]

An unusual bilateral ring-shaped corneal opacity has been observed in two patients. Biomicroscopical characteristics are minute greyish dots which are distributed within the outer stromal layers forming an arcus lipoides-like circular band. Besides of a typical arcus senilis no other corneal anomalies can be found. Up to date only 4 patients with similar corneal opacities have been described. Etiology remains unclear and according to the author who has first described this symptom we propose to name this corneal anomaly "Ascher-Ringe".

[Peripheral retinal streaks. Linear depigmentation of the peripheral retinal pigment epithelium]

An unusual peripheral depigmented streak lesion of the retina is described in three patients. This depigmented line is located in the equatorial region running parallel to the ora serrata and seems to result from a focal reduction or loss of pigmentation in the retinal pigment epithelium. Similar lesions have been reported as a symptom of the presumed ocular histoplasmosis syndrome (POHS) called linear streaks of the equator. As we did not find any additional symptoms of POHS in our patients, the aetiology of this peripheral depigmented streaks remains unclear.

[Lectin histochemical studies of retinal pigment epithelium in retinal detachment]

The retinal pigment epithelium (RPE) exhibits a broad spectrum of morphological changes under pathological conditions. Since RPE cells cannot be immunocytochemically characterized with certainty, lectin histochemical investigations were performed to study the lectin binding pattern of different morphological RPE variants in human globes. Normal RPE with attached retinas was compared to reactive changes in RPE following retinal detachment. Lectin binding sites were visualized by a modified PAP technique performed on paraffin-embedded tissue sections. Eight lectins of different sugar affinity (Con A, WGA, PNA, RCA 1, SBA, UEA 1, DBA, LPA) were tested for binding sites on the RPE. Both normal and reactively changed RPE possess receptors for Con A, WGA, PNA, and RCA 1. Modifications in the lectin binding pattern occurred simultaneously with the morphological changes within the RPE cells. RPE cells which form a monolayer on Bruch's membrane mainly have lectin binding sites in their apical portions. Proliferating and migrating RPE cells, especially RPE macrophages, which have withdrawn from the basal cell layer were found to contain lectin binding sites dispersed over the entire cytoplasm. RPE macrophages exhibited additional binding sites for the lectin SBA. These results indicate that RPE cell variants can be designated by means of their specific combination of lectin binding sites for Con A WGA, PNA, and RCA 1 not found on other cell types in the retina.

[Results after retinotomy and retinectomy in the treatment of complicated retinal detachment]

Of 241 cases operated with pars-plana vitrectomy and silicone oil filling for complicated retinal detachment we performed retinotomies for drainage of subretinal fluid or removal of subretinal strands in 48 cases (20%) and retinectomies for relief of traction in 80 cases (33%). We found no negative influence of these retinotomies and retinectomies on the anatomic or functional outcome in our major indication groups--PVR, PDR and perforating injury. With increasing size of the retinectomy the anatomic success rate fell from 100% in cases with a 90 degrees retinectomy to 76% with a retinectomy larger than 270 degrees. In 21 out of 80 cases traction relief was insufficient so that we had to enlarge the retinectomy. 17 of these 21 cases could then be attached permanently.

[No disorder of arachidonic acid-induced thrombocyte aggregation in familial exudative vitreoretinopathy]

Six patients, members of a family with familial exudative vitreoretinopathy (FEVR), were studied to verify whether the disease was associated with a suspected platelet aggregation defect. No hemostaseologic defect was found in either the affected or healthy members of the family; in particular, there were no grounds for suspecting any disturbance of arachidonic acid-induced platelet aggregation.

[Secondary pigmented macular pucker]

The clinical course and histologic findings in a case of macular pucker with secondary pigmentation are described. The macular pucker occurred following argon laser coagulation of a peripheral hole and consisted of elements of the inner limiting membrane, an extracellular matrix of collagen fibrils, and retinal pigment epithelial cells with varying degrees of differentiation. No retinal glial cells were found. The pigment epithelial cells had presumably migrated through the peripheral retinal hole and settled on the retinal surface.