Virus-associated anterior uveitis and secondary glaucoma: Diagnostics, clinical characteristics, and surgical options

In this retrospective, single-center, observational study, we compared the clinical characteristics, analyzed the glaucoma development, and the glaucoma surgery requirement mediators in patients with different virus-associated anterior uveitis (VAU). In total, 270 patients (= eyes) with VAU confirmed by positive Goldmann-Witmer coefficients (GWC) for cytomegalovirus (CMV), herpes simplex virus (HSV), varicella-zoster virus (VZV), rubella virus (RV), and multiple virus (MV) were included. Clinical records of these patients were analyzed. Demographic constitution, clinical findings, glaucoma development, and surgeries were recorded. The concentrations of 27 immune mediators were measured in 150 samples of aqueous humor. The GWC analysis demonstrated positive results for CMV in 57 (21%), HSV in 77 (29%), VZV in 45 (17%), RV in 77 (29%), and MV in 14 (5%) patients. CMV and RV AU occurred predominantly in younger and male patients, while VZV and HSV AU appeared mainly with the elderly and females (P<0.0001). The clinical features of all viruses revealed many similarities. In total, 52 patients (19%) showed glaucomatous damage and of these, 27 patients (10%) needed a glaucoma surgery. Minimal-invasive glaucoma surgery (MIGS) showed a reliable IOP reduction in the short-term period. In 10 patients (37%), the first surgical intervention failed and a follow-up surgery was required. We conclude that different virus entities in anterior uveitis present specific risks for the development of glaucoma as well as necessary surgery. MIGS can be suggested as first-line-treatment in individual cases, however, the device needs to be carefully chosen by experienced specialists based on the individual needs of the patient. Filtrating glaucoma surgery can be recommended in VAU as an effective therapy to reduce the IOP over a longer period of time.

Different composition of intraocular immune mediators in Posner-Schlossman-Syndrome and Fuchs' Uveitis

Posner-Schlossman-Syndrome (PSS) is clinically characterized by acute, recurrent, mild, unilateral uveitis anterior accompanied by elevated intraocular pressure (IOP). Fuchs´ Uveitis (FU) is a chronic, low-grade-inflammatory disorder, involving anterior uvea and vitreous. The clinical findings show remarkable similarities as well as differences. In our study, we determine the composition of immune mediators in aqueous humor of patients with PSS and FU and evaluate if immune mediators play a crucial role in specific viral intraocular inflammation and IOP rises. Aqueous humor samples from 81 uveitis patients (= eyes) presenting with either PSS or FU were collected at one time point. Local intraocular antibody synthesis to rubella virus was confirmed in 65 patients, whereas 16 were tested positively for human cytomegalovirus. Thirteen patients with PSS and 10 patients with FU were treated with glaucoma medications. Additionally, 11 cataract patients acted as control group. Immune mediator concentrations were measured by Bio-Plex Pro assay. We observed in both PSS (IFN-γ: 174.9 pg/mL; TNF-α: 25.1 pg/mL) and FU (IFN-γ: 25.4 pg/mL; TNF-α: 27.2 pg/mL) groups a significantly increased level of T-helper 1 immune mediators compared to controls (IFN-γ, TNF-α: 0 pg/mL) [median]. Notably, PSS patients (IL-1RA: 73.4 pg/mL; IL-8: 199.4 pg/mL; IL-10: 33.4 pg/mL; IP-10: 126350 pg/mL) showed a stronger and more active ocular inflammatory response, than FU patients (IL-1RA: 4.3 pg/mL; IL-8: 72.4 pg/mL; IL-10: 1.6 pg/mL; IP-10: 57400 pg/mL). Furthermore, a negative correlation between mediators and IOP was seen in the PSS group, potentially caused by acetazolamide-treatment. Our findings show that immune mediators play a crucial role in specific viral intraocular inflammation and influence IOP levels. Remarkable similarities but also significant differences of immune mediator concentrations are apparent in PSS compared to FU. High concentrations of IL-1RA, IL-8, IL-10, and IP-10 correlate with active inflammation in PSS, while FU may trigger chronic inflammation. Our data also substantiated a very similar composition of cytokines in those patients from the PSS group suffering from ocular hypertension and thus offers a potential explanation model for a negative correlation between mediators and IOP.

Toxoplasma serotype is associated with development of ocular toxoplasmosis

BACKGROUND

Worldwide, ocular toxoplasmosis (OT) is the principal cause of posterior uveitis, a severe, life-altering disease. A Toxoplasma gondii enzyme-linked immunoassay that detects strain-specific antibodies present in serum was used to correlate serotype with disease.

METHODS

Toxoplasma serotypes in consecutive serum samples from German uveitis patients with OT were compared with non-OT seropositive patients with noninfectious autoimmune posterior uveitis. OT patients were tested for association of parasite serotype with age, gender, location, clinical onset, size, visual acuity, or number of lesions (mean follow-up, 3.8 years) to determine association with recurrences.

RESULTS

A novel, nonreactive (NR) serotype was detected more frequently in serum samples of OT patients (50/114, 44%) than in non-OT patients (4/56, 7%) (odds ratio, 10.0; 95% confidence interval 3.4-40.8; P < .0001). Non-OT patients were predominantly infected with Type II strains (39/56; 70%), consistent with expected frequencies in Central Europe. Among OT patients, those with NR serotypes experienced more frequent recurrences (P = .037). Polymerase chain reaction detected parasite DNA in 8/60 OT aqueous humor specimens but failed to identify Type II strain alleles.

CONCLUSIONS

Toxoplasma NR and Type II serotypes predominate in German OT patients. The NR serotype is associated with OT recurrences, underscoring the value of screening for management of disease.

Single-photon emission from electrically driven InP quantum dots epitaxially grown on CMOS-compatible Si(001)

The heteroepitaxy of III-V semiconductors on silicon is a promising approach for making silicon a photonic platform. Mismatches in material properties, however, present a major challenge, leading to high defect densities in the epitaxial layers and adversely affecting radiative recombination processes. However, nanostructures, such as quantum dots, have been found to grow defect-free even in a suboptimal environment. Here we present the first realization of indium phosphide quantum dots on exactly oriented Si(001), grown by metal-organic vapour-phase epitaxy. We report electrically driven single-photon emission in the red spectral region, meeting the wavelength range of silicon avalanche photodiodes' highest detection efficiency.

Gene transfer of cyto-protective molecules in corneal endothelial cells and cultured corneas: analysis of protective effects in vitro and in vivo

The loss of corneal endothelial cells plays a critical role in many corneal diseases and is a common phenomenon following cornea transplantation. In addition, the non-regenerative capacity of human corneal endothelial cells (HCEC) ultimately requires appropriate protection of corneal tissues during ex vivo storage to ensure vitality of the cells. However, only 70% of donor corneas can be used for grafting because of endothelial deficiencies. Corneal endothelial cell loss during storage is mainly induced by apoptotic cell death. This study was undertaken, for proof of principle, to investigate whether over-expression of cyto-protective molecules Bcl-x(L), Bag-1, and HO-1 prevents the loss of corneal endothelial cells both in vitro and in vivo. We demonstrate that gene transfer of both Bcl-x(L) and HO-1 has cyto-protective effects on HCEC in vitro. However, gene transfer of a single cyto-protective molecule does not prevent its rejection upon transplantation in a MHC class I/II disparate rat model.

Specific antibody production in herpes keratitis: intraocular inflammation and corneal neovascularisation as predicting factors

PURPOSE

The purpose of the study is to investigate whether analysis of specific antibody synthesis can aid the diagnosis of herpes keratitis.

METHODS

Aqueous humor was collected from 39 patients with presumed recurrent herpes keratitis, including 23 consulting for keratitis and 16 patients scheduled for penetrating keratoplasty. Local antibody production was ascertained by analysis of paired aqueous humor/serum samples, using a modified micro-ELISA technique.

RESULTS

Local production of antibodies was found in 32 patients (82%): anti-herpes simplex virus (HSV) antibodies in 26 (67%) and anti-varicella zoster virus (VZV) antibodies in 11 (28%). Twenty of 23 patients with active keratitis (87%), and 12 of 16 undergoing keratoplasty (75%), tested positive. Five patients had local production of both anti-HSV and anti-VZV antibodies, whereas seven patients tested negative. Local antibody production was significantly associated with intraocular inflammation (P<0.05), corneal neovascularisation (P<0.05), and positive response to anti-viral treatment (P<0.05). No complications were encountered in sampling aqueous humor.

CONCLUSIONS

Assessment of local anti-HSV and -VZV antibody production is a safe and reliable diagnostic procedure for recurrent herpes keratitis. It might be particularly helpful in patients presenting with intraocular inflammation and neovascularisation since it discriminates between herpes and non-herpes pathologies and may therefore be useful for preventive and therapeutic strategies.

Fibroblast growth factor-2 protects endothelial cells from damage after corneal storage at 4 degrees C

BACKGROUND

Since the introduction of cold corneoscleral segment storage prior to keratoplasty there have been continuous efforts to ameliorate the preservation media in order to better maintain the quality of the corneal epi- and endothelium. Recent studies have shown that basic fibroblast growth factor (FGF-2) preserves the viability of, for example, retinal ganglion cells and pigment epithelium cells. Therefore, we investigated the effect of different concentrations of FGF-2 added to a modified Optisol storage medium on endothelial damage after corneal storage at 4 degrees C.

METHODS

. Bovine corneas were stored at 4 degrees C for 14 days and for another 24 h at 34 degrees C. Various FGF-2 concentrations (4, 20 and 40 ng/ml) were added to the medium either at day (D) 1, D14, or both D1 and D14. Quantitative evaluation of corneal damage after 14+1 days of storage was conducted by means of the Janus green photometry assay. Histological and ultrastructural investigations of the preserved endothelium were also performed. Bovine cell culture experiments using the TUNEL assay aimed to elucidate the role of FGF-2 on prevention of endothelial apoptosis.

RESULTS

The mean endothelial damage in control corneas increased from 4.9 +/- 1.8% (fresh corneas) to 13.4 +/- 2.4% after 14+1 days of storage. FGF-2 at 20 ng/ml or 40 ng/ml added at any of the indicated time points significantly reduced the overall endothelial damage by 5.1-7.3%, corresponding to 38-54% less endothelial damage than in control corneas (P<0.001). Light- and electron microscopic investigations confirmed this protective effect of FGF-2 on corneal endothelial cells. The TUNEL assay revealed a true anti-apoptotic effect of FGF-2 on endothelial cells in culture.

CONCLUSION

Our study clearly demonstrates the effectiveness of FGF-2 to enhance cell survival of the corneal endothelium after storage at 4 degrees C. A clinical interest could be seen in the potential future application of FGF-2 as an adjuvant to corneal preservation media in order to better maintain endothelial viability during corneal storage.

[Ocular toxoplasmosis antibodies in aqueous humor and serum]

BACKGROUND

The diagnosis of ocular toxoplasmosis is mainly based on ophthalmological examination but might be difficult to establish in some cases. The purpose of our study was to evaluate the value of aqueous humor and serum analysis in ocular toxoplasmosis.

PATIENTS AND METHODS

We analyzed the avidity of toxoplasma-specific IgG in aqueous humor and serum samples from 50 patients with toxoplasmic retinochoroiditis, with 25 patients with uveitis posterior or panuveitis serving as controls.

RESULTS

Specific intraocular antibody synthesis could be confirmed in 49 patients (98%). In two patients (8%) of the control group, antibody synthesis was detected (false positive). Forty-nine patients with diagnoses of ocular toxoplasmosis were positive for serum anti-T. gondii IgG, but only three patients had increased IgM levels.

CONCLUSIONS

Analysis of local antibody production is a reliable method for confirming or excluding a suspected clinical diagnosis of toxoplasma retinochoroiditis. The determination of toxoplasma antibodies in the patients' serum is of limited value.

Genomic expression responses to DNA-damaging agents and the regulatory role of the yeast ATR homolog Mec1p

Eukaryotic cells respond to DNA damage by arresting the cell cycle and modulating gene expression to ensure efficient DNA repair. The human ATR kinase and its homolog in yeast, MEC1, play central roles in transducing the damage signal. To characterize the role of the Mec1 pathway in modulating the cellular response to DNA damage, we used DNA microarrays to observe genomic expression in Saccharomyces cerevisiae responding to two different DNA-damaging agents. We compared the genome-wide expression patterns of wild-type cells and mutants defective in Mec1 signaling, including mec1, dun1, and crt1 mutants, under normal growth conditions and in response to the methylating-agent methylmethane sulfonate (MMS) and ionizing radiation. Here, we present a comparative analysis of wild-type and mutant cells responding to these DNA-damaging agents, and identify specific features of the gene expression responses that are dependent on the Mec1 pathway. Among the hundreds of genes whose expression was affected by Mec1p, one set of genes appears to represent an MEC1-dependent expression signature of DNA damage. Other aspects of the genomic responses were independent of Mec1p, and likely independent of DNA damage, suggesting the pleiotropic effects of MMS and ionizing radiation. The complete data set as well as supplemental materials is available at http://www-genome.stanford.edu/mec1.

Effects of fluoroquinolones on the locomotor activity in rats

During therapy with fluoroquinolones adverse CNS reactions such as dizziness, light-headedness, insomnia or sleepiness are observed in up to 20% of patients. Using a device developed at our institute for the simultaneous registration of the activity of rats housed in single cages, we have investigated the effects of trovafloxacin, fleroxacin or ofloxacin on the locomotor activity of juvenile and adult rats (11 per group) after oral administration of 600 mg/kg for 5 consecutive days. The effects were most pronounced after fleroxacin, which induced a reduction in activity to 36 +/- 9% (mean +/- SD) of the values measured in juvenile rats before treatment and to 60 +/- 21% (mean +/- SD) in adult rats. HPLC analysis of the plasma concentrations in juvenile rats showed that the concentrations of trovafloxacin were considerably lower than those of the other fluoroquinolones that had been studied previously in our laboratory: the peak concentration of trovafloxacin was 14 +/- 2.9 mg/l (mean +/- SD) after a single dose of 600 mg/kg in juvenile rats. Overall, we showed that the locomotor activities of juvenile and adult rats were significantly depressed during treatment with fluoroquinolones. The effects were more pronounced in juveniles. Monitoring of the locomotor activity of rats is a suitable approach to study CNS effects of fluoroquinolones in animals, but pharmacokinetics have to be taken into account.

Nuclear localization and increased levels of transcription factor YB-1 in primary human breast cancers are associated with intrinsic MDR1 gene expression

Breast cancers are either primarily resistant to chemotherapy (intrinsic resistance), or respond to chemotherapy but later recur with a multidrug-resistant phenotype because of overexpression of the multidrug transporter P-glycoprotein. The MDR1 gene encoding P-glycoprotein may be transcriptionally regulated by a Y-box transcription factor. We now report that, in multidrug-resistant MCF-7 breast cancer cells, nuclear localization of YB-1 is associated with MDR-1 gene expression. In drug-sensitive MCF-7 cells, however, YB-1 was localized to the cytoplasm. Regulated overexpression of YB-1 in drug-sensitive diploid breast epithelial cells induced MDR-1 gene expression and multidrug resistance. In 27 out of 27 untreated primary breast cancers, YB-1 protein was expressed in the cytoplasm although it was undetectable in normal breast tissue of these patients. In a subgroup of tumors (9/27), however, YB-1 was also localized to the nucleus and, in these cases, high levels of P-glycoprotein were present. These results show that in a subset of untreated primary breast cancers, nuclear localization of YB-1 protein is associated with intrinsic multidrug resistance. Our data show that YB-1 has an important role in controlling MDR1 gene transcription and this finding provides a basis for the analysis of molecular mechanisms responsible for intrinsic multidrug resistance in human breast cancer.