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H Baatz

Publications and source records attributed to H Baatz.

At least 19 recordsLinked to original sources
PubMed2007

[Pseudoangiitis in bilateral ocular ischemia].

BACKGROUND: The term 'frosted branch angiitis' was initially used to describe an idiopathic form of vasculitis in association with panuveitis. It has since also been used to describe the angiographic phenomenon of diffuse leakage along retinal vessels against the background of other ocular and systemic diseases. METHODS: We describe a 57-year-old male patient with acute bilateral reduction of visual acuity, headaches and absence of any pulse at the temporal arteries. Fluorescence angiography showed bilateral diffuse leakage along all the retinal vessels, which resembled frosted branches. Laboratory parameters and histology were not indicative of vasculitis. Imaging showed complete occlusion of both common carotid arteries and a hypoplastic vertebral artery on the left. CONCLUSIONS: Ocular ischemia may imitate primarily inflammatory conditions in its angiographic appearance.

Angiography↗
PubMed2006

[Uveitis and the aging].

Uveitis can be found in all age groups, but the age of disease onset may provide important information on the etiology of the disease. New data on the epidemiology of uveitis disclose a higher incidence and prevalence in older patients then has previously been found. Masquerade syndromes which mimic uveitis may be found especially in younger and older patients. These have to be excluded from regular intraocular inflammation. Here, intraocular lymphoma plays a major role which is most often associated with severe clinical, diagnostic and therapeutic challenges. One of the major complications of uveitis is cataract formation. Keeping in mind the importance of pre- and postoperative treatment, even implantation of an intraocular lens in older patients with uveitis is currently a safe procedure.

Age Factors↗
PubMed2006

[Posterior segment complications of laser in situ keratomileusis (LASIK)--a survey of the literature].

During the past years refractive surgical procedures and particularly laser IN SITU keratomileusis (LASIK) have become established by clinical and experimental studies and are performed worldwide in a high number. This paper provides a survey of the published posterior segment complications of LASIK that may occur albeit very rarely. Additionally, current clinical and experimental hypotheses regarding the pathogenesis of those complications are discussed. Currently a cause-effect relationship between LASIK and reported posterior segment complications has not been proven although a very high number of LASIK procedures have been performed worldwide.

Choroid↗
PubMed2005

[Macular translocation after photodynamic therapy: a case report].

BACKGROUND: Photodynamic therapy (PDT) and surgical macular translocation are concurrent treatment options for exudative age-related macular degeneration (ARMD). PDT is currently favoured because of positive study results and the non-invasive technique. We report a case of macular translocation with 360 degrees retinotomy after unsuccessful previous PDT for treatment of ARMD. CASE REPORT: PDT with verteporfin was performed in the left eye of a 79-year-old patient with exudative ARMD and predominantly classic juxtafoveal choroidal neovascularisation (CNV). Because of continuing visual loss and deteriorating angiographic signs three months after PDT, a surgical macular translocation with 360 degrees retinotomy was performed successfully. During the surgery increased adhesion between the CNV and the retina was observed in contrast to patients without previous PDT. In a second step three months later, counter-rotation of the ocular globe was achieved by muscle surgery and the silicone oil was removed in the same session. The best spectacle corrected visual acuity improved from 0.1 before the surgery to 0.4 nine months thereafter (six Snellen lines). No CNV recurrence was observed. Patient satisfaction with the surgery outcome is high. CONCLUSIONS: Macular translocation may be considered in cases of continuing deterioration after a previous PDT for treatment of exudative ARMD. Possible complications must be discussed with the patient. Intraoperatively, increased adhesion of CNV to the retina was observed, which might increase the risk of inadvertent damage to the retina during surgery.

Aged↗
PubMed2004

Acute retinal necrosis six years after herpes simplex encephalitis: an elusive immune deficit suggested by insufficient test sensitivity.

A patient presented with acute retinal necrosis of the left eye. Demonstration of herpes simplex virus (HSV) DNA in the aqueous humour confirmed the diagnosis. Negative results of HSV type-specific antibody tests based on gG antigens suggested a primary HSV infection. However, the patient had a past history of laboratory-confirmed herpes simplex encephalitis 6 years ago. Using antibody tests based on whole viral lysate antigens, he was seropositive from the onset, and immunoblot testing confirmed a lack of anti-gG reactivity. To be able to assess whether this might be related to the apparent inability of his immune system to suppress clinically symptomatic HSV infection, serial samples were tested by an HSV neutralisation test and a whole-blood flow cytometric assay to determine the frequency of HSV-specific CD4 lymphocytes. However, this did not yield evidence of obvious immunodeficiency; the patient reacted similarly to known positive controls by both assays. Although type-specific HSV serological tests based on gG are generally more specific than those based on whole viral lysate antigens, they have a somewhat lower sensitivity, as a certain percentage of HSV-infected individuals do not develop antibodies against gG, and others may suffer a secondary loss of anti-gG reactivity. Thus there is a risk of missing individual infected patients. Unless this potential problem is recognised, serious consequences might possibly result. We therefore urge virologists and clinicians to exercise great care if highly specific antibody assays based on recombinant proteins are employed.

Antibodies, Viral↗
PubMed2003

Tumour necrosis factor alpha and interleukin 6 gene expression in keratocytes from patients with rheumatoid corneal ulcerations.

BACKGROUND/AIMS: Ultrastructural alterations in the stroma adjacent to corneal perforations have previously been reported in patients with longstanding rheumatoid arthritis. Since patients with rheumatoid arthritis often present upregulation of proinflammatory cytokines in serum and in synovial fluid, it was of interest to analyse the gene expression of these cytokines-for example, tumour necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6), in corneal samples from patients with corneal ulcerations and/or perforations associated with rheumatoid arthritis. METHODS: Corneal samples from seven patients with corneal ulcerations and/or perforations associated with rheumatoid arthritis were collected in 4% paraformaldehyde in "RNAse-free" conditions. Paraffin sections were fixed on silan coated slides and further analysed by systematic non-radioactive in situ hybridisation, using specific gene probes for TNF-alpha and IL-6 labelled with digoxigenin (DIG). Detection of hybrids was carried out by using a commercially available DIG detection system. RESULTS: Whereas an extended TNF-alpha gene expression could be clearly observed in the keratocytes surrounding the corneal ulcerations and/or perforations from five of the seven analysed patients, all seven patients presented clearly positive results for an extended IL-6 gene expression in the analysed tissue samples. CONCLUSIONS: Alterations in corneal cells surrounding ulcerations and/or perforations in patients with rheumatoid arthritis may occur with implication for inflammatory processes. Upregulation of the proinflammatory cytokines TNF-alpha and IL-6 may modify the production of metalloproteinases in the corresponding cells resulting in collagenolytic corneal damage.

Aged↗
PubMed2002

[Macrophage depletion inhibits leukocyte recruitment in experimental melanin-induced uveitis (EMIU)].

BACKGROUND: To study the role of macrophages in experimental melanin-induced uveitis (EMIU), we used the method of intravital microscopy to analyse changes in leukocyte adhesion to iris venules of live rats with EMIU after pretreatment with liposomal clodronate. MATERIALS AND METHODS: EMIU was induced in Lewis rats (n = 48) by intraperitoneal immunisation with bovine crude melanosomes emulsified in complete Freund's adjuvant (CFA) and pertussis toxin (PTX). Control animals received CFA and PTX only (n = 12) or no injection (n = 6). Animals were treated with liposomal clodronate (DMDP-lip) or empty liposomes on days -2, +1, 4, 6 and 8. Using IVM, postcapillary iris venules of rats were examined to quantify leukocyte rolling and firm adhesion to the vascular endothelium. RESULTS: Depletion of macrophages caused a decreased percentage of rolling leukocytes on day 8 (2 +/- 1.1% vs 15.2 +/- 1.6%, DMDP-lip vs EMIU, mean +/- SEM, ANOVA, p < 0.05) and day 10 (2.6 +/- 0.3% vs 14.2 +/- 1.6%). A significant decline in the number of firmly adherent leukocytes was detected on days 8 and 10 (88 +/- 13/mm2 vs 175 +/- 18/mm2 and 129 +/- 13/mm2 vs 372 +/- 31/mm2, DMDP-lip vs EMIU). Treatment with empty liposomes showed no changes in leukocyte firm adhesion. CONCLUSIONS: Elimination of macrophages prevents the induction of EMIU. In autoimmune-mediated uveitis, macrophages play a crucial role in the initiation of leukocyte-endothelium interaction.

Animals↗
PubMed2001

Macrophage depletion prevents leukocyte adhesion and disease induction in experimental melanin-protein induced uveitis.

The purpose was to study the effects of macrophage depletion with liposomal dichloromethylene-diphosphonate (Cl(2)MDP-lip) on inflammation and leukocyte-endothelium interaction in experimental melanin-protein induced uveitis (EMIU). Lewis rats (n = 48) were immunized with melanin-associated protein in complete Freund's adjuvant and pertussis toxin. Control groups received adjuvants without the antigen (n = 12) or no injection (n = 6). Animals received treatment with either CL(2)MDP-lip or empty liposomes (empty-lip) on day -2, 1, 4, 6 and 8. Leukocytes were stained with rhodamine 6G i.v. and intravital fluorescence microscopy (IVM) was performed on day 4, 6, 8 and 10 to quantify leukocyte rolling and arrest. After IVM, the cell count and protein concentration were determined in aqueous humor and plasma levels of TNF-alpha and IFN-gamma were measured by ELISA. In EMIU, leukocyte rolling increased on day 4 (10.0 +/- 1.2 cells min(-1)vs baseline of 5.7 +/- 0.7 cells min(-1), mean +/- S.E.(M.)) and peaked on day 8 (40.8 +/- 4.2 cells min(-1);P < or = 0.05). Leukocyte arrest was increased on day 8 (175.4 +/- 18.2 cells mm(-2)vs baseline of 59.7 +/- 7.1 cells mm(-2);P < or = 0.05) and day 10 (371.7 +/- 30.7 cells mm(-2)). CL(2)MDP-lip prevented leukocyte rolling (day 10: 16.6 +/- 1.8 cells min(-1)vs 30.7 +/- 2.9 cells min(-1); CL(2)MDP-lip vs untreated EMIU;P < or = 0.05) and arrest (day 8: 88.3 +/- 13 cells mm(-2); day 10: 128.5 +/- 12.9 cells mm(-2);P < or = 0.05). Empty-lip had no effect on leukocyte rolling (day 10: 34.8 +/- 4.2 cells min(-1)) or arrest (day 8: 159.3 +/- 12.9 cells mm(-2), day 10: 421.2 +/- 41.6 cells mm(-2)). CL(2)MDP-lip completely suppressed leukocyte emigration (11 +/- 2 cells microl(-1)vs 100 +/- 29 cells microl(-1); CL(2)MDP-lip vs empty-lip;P < or = 0.05) and protein extravasation into aqueous humor (2.7 +/- 0.3 mg ml(-1)vs 14.2 +/- 2.1 mg ml(-1); CL(2)MDP-lip vs empty-lip;P < or = 0.05), abrogated the TNF-alpha response (32.5 +/- 2.7 pg ml(-1)vs 954.9 +/- 216.3 pg ml(-1); CL(2)MDP-lip vs untreated EMIU;P < or = 0.05) and caused an attenuated and delayed elevation of IFN-gamma. CL(2)MDP-lip prevented the inflammatory reaction of EMIU and inhibited the increase of leukocyte-endothelium interaction in iris vessels. Our findings emphasize the pivotal role macrophages play in the initiation of autoimmune disease.

Analysis of Variance↗
PubMed2001

Modulation of leukocyte-endothelium interaction by nitric oxide synthase inhibitors: effects on leukocyte adhesion in endotoxin-induced uveitis.

OBJECTIVE AND DESIGN: To examine the effects of the nitric oxide synthase (NOS) inhibitors aminoguanidine (AG) and L-NAME on leukocyte adhesion in endotoxin-induced uveitis (EIU). MATERIAL: Uveitis was induced in Lewis rats (n = 124) by LPS injection (Salmonella typhimurium). TREATMENT: Rats either (1) did not receive any LPS or other treatments (controls), received (2) only subcutaneous saline injections with LPS administration, (3) a single s.c. dose of AG (100 mg/kg body weight) at the time of LPS administration, (4) a single s.c. injection of AG 8 h after LPS injection, (5) s.c. injections of AG at the time of LPS administration and 8 h after LPS injection or (6) received a single dose of L-NAME (75 mg/kg body weight) at the time of LPS administration. METHODS: Intravital microscopy (IVM) of iris vessels was performed at 2, 4, 8, 16, 24 and 48 h after endotoxin injection. Aqueous humor analysis for protein concentration and cell count was performed after IVM. RESULTS: At 2 h after the induction of uveitis, significantly more rolling leukocytes were detected in the AG and L-NAME-treated group than in untreated EIU (4.8 +/- 0.31 and 9.83 +/- 0.64 vs. 2.85 +/- 0.37%, mean +/- SEM, p < 0.01). However, at 16 h the percentage of rolling leukocytes was significantly reduced in all groups which had received AG (LPS: 8.08 +/- 0.37%; LPS/AG 0 h: 3.78 +/- 0.25%; LPS/AG 8 h: 5.34 +/- 0.3%; LPS/AG 0+8h: 3.86 +/- 0.31%). L-NAME enhanced leukocyte rolling even at 24 h after LPS (12.38 +/- 0.64%). Early treatment of EIU with AG significantly reduced the number of sticking leukocytes at 4, 8 and 24 h (306 +/- 13 vs. 571 +/- 41, 228 +/- 12 vs. 345 +/- 19 and 240 +/- 14 vs. 469 +/- 23 cells/mm2, respectively). L-NAME inhibited LPS-induced sticking of leukocytes at all observed time points and this effect was most pronounced at 24 h (147 +/- 10 vs. 469 +/- 23 cells/mm2). CONCLUSIONS: In EIU, administration of AG or L-NAME causes enhanced leukocyte rolling in the early inflammatory response. However, firm adhesion of leukocytes to the vascular endothelium decreases and this effect prevails, ameliorating leukocyte infiltration.

Animals↗
PubMed2001

[In vitro bovine and human lens epithelial cell culture studies on inhibition of posterior capsule opacification using a cyclic RGD peptide].

BACKGROUND: RGD peptides competitively inihibit adhesion molecules of the lens epithelial cells (LEC). The purpose of our study was to investigate whether this peptide is capable of detaching adherent cells and preventing posterior capsule opacification (PCO). METHODS: Cultures of bovine and human LECs on culture dishes and discs of bovine anterior lens capsules were used. The inhibition of adhesion and the detachment of confluent LEC layers by the cyclic RGD peptide cRGDdFV were studied (incubation time was 3 days and 1 h and concentrations of 10(-4) and 10(-3) M were used). RESULTS: A dose-dependent inhibition of adhesion (48% and 42%, respectively) was obtained. There was a significant difference between the control peptide group and cRGDdFV (p < 0.0001). Cell detachment from lens capsules was not achieved but complete detachment from the culture dish occurred after 37 min. CONCLUSIONS: Short-term incubation of LECs by cRGDdFV did not lead to a sufficient inhibition of adhesion in vitro. A detachment of adherent LECs by cRGDdFV was not achieved.

Adhesiveness↗
PubMed2000

Inhibition of corneal neovascularization by alpha(v)-integrin antagonists in the rat.

BACKGROUND: The proliferation of vascular endothelial cells and ultimately angiogenesis is inhibited by blocking integrin-mediated cell-matrix interaction. To asses the therapeutic potential of alpha(v)-integrin antagonists LM609 and cRGDfV in neovascularization of the anterior segment, their inhibitory effect on angiogenesis was studied in two rat models for corneal neovascularization. METHODS: Corneal neovascularization was induced in Wistar rats (n=51) either by silver nitrate burns or intrastromal implantation of polymer pellets containing 400 ng of fibroblast growth factor (bFGF). Animals were treated with subcutaneous injections of a cyclic alpha(v)-integrin antagonist (cRGDfV, 15 mg/kg body wt) or saline twice daily. Additional animals received intrastromal implants containing 400 ng bFGF together with either Lm609 (mAb, anti-alpha(v)beta(3)) or control antibody. Four days later, the animals were killed and the percentage of the surface area covered with vessels determined using digital image analysis. RESULTS: Systemic treatment with cRGDfV resulted in a significant reduction of corneal vessel growth in animals with bFGF-induced corneal vascularization. In corneas with silver nitrate burns, systemic cRGDfV treatment showed no significant reduction of vascularization compared with controls. Pellets containing bFGF and LM609 mAb induced significantly less neovascularization than pellets containing bFGF and control mAb. CONCLUSION: Our results suggest that in the rat cornea, alpha(v)beta(3) ligation does inhibit bFGF-induced neovascularization. A chemical burn of the cornea induces angiogenisis which is not inhibited by blocking alpha(v)-integrins. This suggests an angiogenic pathway independent of alpha(v)-integrins.

Animals↗
PubMed2000

Detection of tumor necrosis factor alpha and interleukin 1 alpha gene expression in human lens epithelial cells.

PURPOSE: To analyze the gene expression of interleukin-1 alpha (IL-1 alpha) and tumor necrosis factor alpha (TNF alpha) in human lens epithelial cells (LECs) by in situ RNA hybridization. SETTING: Department of Ophthalmology and Laboratory for Molecular Biology, Charité, Humboldt University, Berlin, Germany. METHODS: Anterior lens capsules with attached LECs were collected in RNase-free conditions from 10 consecutive patients during cataract surgery. Samples were then systematically analyzed by an in situ RNA-hybridization technique using specific gene probes for IL-1 alpha and TNF alpha, which were previously labeled with digoxigenin (DIG). RESULTS: The LECs tested positive for DIG-labeled gene probes in the described conditions. One (10%) patient showed a clearly detectable IL-1 alpha gene expression, and 7 (70%) showed a widely positive reaction for TNF alpha mRNA. CONCLUSION: The TNF alpha gene expression in LECs was more extended than that of IL-1 alpha in lens capsule samples from cataract surgery. Active synthesis of TNF alpha and IL-1 alpha may have consequences for postoperative inflammation and LEC proliferation.

Aged↗
PubMed1999

Delayed mustard gas keratopathy: clinical findings and confocal microscopy.

PURPOSE: To describe the clinical manifestations and confocal microscopic findings in a patient with delayed mustard gas keratopathy. METHOD: Case report. A 32-year-old veteran who had participated in the Iran Iraq conflict was exposed to mustard gas in 1988. Ocular abnormalities in 1996 and 1998 and corneal confocal microscopic findings in 1998 are presented. RESULTS: In 1996, slit-lamp examination disclosed bilateral limbal changes with tortuous blood vessels and full-thickness corneal alterations. In 1998, the right eye had porcelain-white episcleral changes and adjacent peripheral ulcerative keratopathy. Confocal microscopy demonstrated irregular-appearing epithelial and basal epithelial cells. The anterior stroma was remarkable for spindle-like keratocytes, diffuse fibrillar inhomogeneities and the presence of highly reflective material. CONCLUSIONS: Mustard gas keratopathy is a uncommon cause of ocular damage, but it may lead to delayed ocular damage.

Adult↗
PubMed1999

[Modulation of immune mediated diseases of the eye].

The eye is the target of a variety of immune mediated diseases. Advances in the field of immunology have permitted a better understanding of these challenges. This progress has been accompanied by the development of more specific immunomodulating agents. Corticosteroids are still a major agent in the management of ocular immunomediated diseases, but are now supplemented by other potent immunomodulating agents. The excitement in pharmacological research has in turn provided more insight in immune mechanisms and some of the newer agents have been used as "probes" for a better understanding of basic mechanisms. In order to better evaluate the indications of certain agents, the properties of established and forthcoming agents are presented. The field of immunopharmacology includes a multitude of preclinical areas related to the development of immunotherapy and immunotoxicology. This review attempts to address some topics of the current knowledge of the use of immunomodulating agents in ophthalmology.

Animals↗
PubMed1997

Fluorescence videomicroscopic assessment of xenogeneic microcirculation and impact of antibody removal by immunoadsorption.

BACKGROUND: Alterations in microcirculation are considered central to the pathogenesis of hyperacute xenogeneic rejection (HXR) of vascularized xenografts, but currently there exist no data describing these microhemodynamic alterations. METHODS: Rat livers were perfused in situ with either isogeneic rat blood or xenogeneic human blood. The microcirculation of these xenoperfused livers was investigated directly using intravital fluorescence microscopy, and compared with that of isogeneic hemoperfused livers. In addition, the impact of antibody depletion by immunoadsorption was investigated. RESULTS: Although a homogenous microcirculation was found during isogeneic liver perfusion (index of acinar perfusion 90.4%/sinusoidal perfusion rate 93.6%), xenoperfusion resulted in a rapid breakdown of the microcirculation (47.5%/67.1%, respectively). Perfusion deficits were found predominantly in the periportal areas. Immunoadsorption reduced the total amount of IgM and IgG by 75.2% and 96.2%, respectively, and caused a significantly improved liver perfusion (80.2%/84.4%) and liver function, as indicated by bile production. In contrast, the massive hepatic leukocyte and platelet accumulation observed during perfusion with untreated xenogeneic blood was not altered by antibody depletion. CONCLUSIONS: Thus, the combination of isolated rat liver perfusion and intravital fluorescence microscopy enables the observation and quantification of the early phase of HXR. This is an important step forward for sensitive characterization of the rejection process and will enable the mechanisms involved in HXR to be elucidated. Antibody depletion was shown to improve liver function and perfusion, but did not reconstitute liver viability to the level of the isogeneic perfusion. These findings highlight the need for additional therapeutic regimens in xenografting.

Acute Disease↗
PubMed1997

Antibacterial protection of the ocular surface.

The outer surface of the eye is constantly exposed to a wide array of microorganisms. To protect the integrity or the ocular surface and to retain corneal transparency, a number of defense mechanisms have evolved. This article discusses the host mechanisms of the eyelids-, tears, cornea and conjunctiva. These host defense mechanisms are identified as either a native, nonspecific defense or a specifically acquired immunological defense requiring previous exposure to an antigen and the development of specific immunity. Nonspecific components that protect the eye include the eyelids, ocular surface epithelium, normal flora and tear proteins. Specifically acquired immunity in tears, cornea and conjunctiva involves the interaction of antigen-presenting cells, lymphocytes and humoral components of the immune system.

Animals↗
PubMed1996

Quantitative analysis of the microcirculation of xenogeneic haemoperfused rat livers by intravital microscopy.

Livers from male Sprague-Dawley rats were perfused with heparinised, unmodified isogeneic rat blood (n = 6) or xenogeneic human blood. The microcirculation of these livers, as the primary manifestation of hyperacute xenogeneic rejection, was directly observed and quantified by using fluorescence videomicroscopy. Bile flow and enzyme release of the isogeneic perfused livers were in the physiological range, whereas bile flow was significantly reduced and enzyme release increased during xenogeneic perfusion. In contrast to an almost physiological acinar (90.4%) and sinusoidal (93.6%) perfusion rate in the isogeneic group, a rapid breakdown of microcirculation with an acinar perfusion index of 47.5% and a sinusoidal perfusion rate of 67.1% were found in the xenogeneic group. This direct quantification of microcirculatory parameters is a step forward towards sensitive and early characterisation of the severity of the xenogeneic rejection of the liver.

Animals↗