We determined homocysteine (Hcy) levels in aqueous humor (AH) and plasma and their association with B-vitamin levels in patients with primary open-angle glaucoma (POAG) and controls. Both AH Hcy and ...plasma Hcy levels were significantly increased in POAG, and elevation of AH Hcy and plasma Hcy was a significant risk factor for POAG. In contrast to controls, neither plasma nor AH Hcy of POAG patients demonstrated a significant association with important non-genetic determinants of elevated Hcy such as low B-vitamin levels, increasing age and caffeine consumption. Considering that Hcy is a neurotoxin that induces apoptotic retinal ganglion cell death via stimulation of the N-methyl-D-asparate (NMDA) receptor, increased Hcy concentrations in AH and plasma might contribute to the optic nerve damage in POAG.
The aim of this study was to outline typical complications after Descemet's stripping automated endothelial keratoplasty (DSAEK) and to discuss their prevention and management.
Our own clinical ...results and PUBMED literature search were evaluated.
Postoperative flap dislocation, which can be effectively treated by re-bubbling the graft, is the most common and typical complication after DSAEK.
Careful preoperative indication, surgery and postoperative care make DSAEK a safe and effective new therapeutic option for patients with endothelial corneal disease.
We assessed homocysteine (Hcy) levels in tear fluid and plasma of patients with primary open-angle glaucoma (POAG). We determined the association between Hcy levels, dry eye syndrome and B vitamin ...status.
This prospective case-control study included 36 patients with POAG and 36 controls. Hcy concentrations were measured by high-performance liquid chromatography.
Patients with POAG had significantly higher mean Hcy levels both in tear fluid (205 +/- 84 nmol/l; p < 0.001, t test) and in plasma (13.43 +/- 3.53 micromol/l; p = 0.001, t test) than control subjects (130 +/- 53 nmol/l and 10.50 +/- 3.33 micromol/l, respectively). Hcy in tear fluid was significantly correlated with plasma Hcy in POAG patients (r = 0.459; p = 0.005, Pearson's correlation), but not in controls (r = 0.068; p = 0.695). POAG patients with dry eye disease had significantly higher Hcy levels both in tear fluid and plasma than POAG patients without dry eye disease. There was no association between Hcy levels and B vitamin status in subjects with POAG.
The study suggests increased Hcy levels in tear fluid and plasma of patients with POAG. Elevated Hcy levels might be a risk factor for POAG and dry eye syndrome in subjects with glaucoma.
The advantages of posterior lamellar keratoplasty (DSAEK) compared to conventional full thickness keratoplasty are faster visual rehabilitation, little change in astigmatism and the absence of ...suture-associated complications. The current study evaluated the satisfaction of the first 15 patients who underwent DSAEK at our clinic.
Evaluation of patient satisfaction was conducted via a telephone survey and by means of a written patient questionnaire. The patients were asked to answer questions on a scale from 1 (very bad) to 10 (very good) about their overall satisfaction with this procedure, their satisfaction with the achieved postoperative visual acuity, their satisfaction with the progress of the healing process and the extent of the perceived burden. The patients were also asked whether they would opt again for the operation. Pre- and postoperative visual acuity, IOP, topographic astigmatism and corneal pachymetry were analysed.
15 eyes of 15 patients were analysed (12 women and 3 men). Average age at the time of operation was 75 +/- 7 years. Visual acuity increased and corneal thickness decreased primarily within the first three months. During that time there was an increase in overall patient satisfaction which finally reached 6.9 +/- 1.8 on the scale. Postoperative visual acuity was awarded with 7.2 +/- 2.0, progress of the healing process with 7.4 +/- 2.3. The procedure was not perceived as a big burden (8.0 +/- 1.9) and most patients would have decided again for the operation (8.2 +/- 2.0). There was no pre- and postoperative difference in IOP and corneal astigmatism.
Like in our group patients with diseases of the corneal endothelium are of higher age and therefore benefit from a fast restitution of visual acuity and a low burden of operation. DSAEK represents a secure and practical procedure to rehabilitate elderly patients with diseases of the corneal endothelium.
To compare the extent of modulation by various growth factors on clonal growth and differentiation between corneal and stem cell-containing limbal epithelium.
A reported serum-free clonal growth ...assay was used. The mitogenic response was measured by colony forming efficiency, colony size, and bromodeoxyuridine labelling index; the differentiation was assessed by AE-5 monoclonal antibody staining.
As compared to controls in an insulin-containing basic medium, the addition of epidermal growth factor, acidic fibroblast growth factor, basic fibroblast growth factor, and a high dose of nerve growth factor was mitogenic for both epithelia. Cholera toxin was also mitogenic, but platelet-derived growth factor might not have, and insulin-like growth factor type I lacked an additive mitogenic effect with insulin. The mitogenic effect of epidermal growth factor differed from the others in its dose-dependent down-regulation and in having more migratory cells in epidermal growth factor-stimulated colonies. In contrast to these mitogens, transforming growth factor-beta 1 exhibited a clear inhibitory effect in the controls as well as in epidermal growth factor- or fibroblast growth factor-stimulated cultures. Transforming growth factor-beta 1's inhibitory effect was correlated with strong AE-5 staining, whereas the mitogenic effect of epidermal growth factors, fibroblast growth factors or nerve growth factors was correlated with the presence of negative AE-5 colonies.
There exist potential dynamic interactions among various growth-modifying cytokines in controlling epithelial growth and differentiation. The lack of specific activation of limbal stem cells in this culture assay also suggests that other unidentified factor(s) might be regulating stem cell functions.
Background and Objectives Pooled nucleic acid amplification techniques (NAT) and donor screening for anti‐hepatitis C virus (HCV) have reduced the diagnostic window period of HCV infection in the ...blood donor population from about 12 to 1 or 2 weeks. During that time, HCV RNA is hardly detectable by pooled or individual donation NAT. Here we describe a case of transfusion‐acquired HCV infection from an extremely low‐titre donation. After a repeat donor tested positive for HCV, a look‐back procedure was initiated. A recipient of a red cell concentrate from the previous donation was identified and found to be infected with HCV as well. We compared several commercial NAT systems for their ability to detect the viraemic plasma.
Materials and Methods Molecular analyses of HCV in donor and recipient samples were performed. The HCV‐transmitting plasma was tested using different commercially available qualitative and quantitative NAT assays.
Results HCV transmission was verified by molecular analyses and was assigned to genotype 2b. NAT with various commercial HCV assays detected the infection erratically in individual donations. However, the detection rate was not directly related to the claimed sensitivity of some HCV NATs.
Conclusions HCV transmission can be caused by donations that escape NAT detection even when tested in an individual donation. Comparison of different assays led to results that did not necessarily reflect the expected sensitivities. The need for standard materials representing further HCV genotypes is discussed.
CERN has been archiving data on tapes in its Computer Center for decades and its archive system is now holding more than 135 PB of HEP data in its premises on high density tapes. For the last 20 ...years, tape areal bit density has been doubling every 30 months, closely following HEP data growth trends. During this period, bits on the tape magnetic substrate have been shrinking exponentially; today's bits are now smaller than most airborne dust particles or even bacteria. Therefore tape media is now more sensitive to contamination from airborne dust particles that can land on the rollers, reels or heads. These can cause scratches on the tape media as it is being mounted or wound on the tape drive resulting in the loss of significant amounts of data. To mitigate this threat, CERN has prototyped and built custom environmental sensors that are hosted in the production tape libraries, sampling the same airflow as the surrounding drives. This paper will expose the problems and challenges we are facing and the solutions we developed in production to better monitor CERN Computer Center environment in tape libraries and to limit the impact of airborne particles on the LHC data.
The IT Storage group at CERN develops the software responsible for archiving to tape the custodial copy of the physics data generated by the LHC experiments. Physics run 3 will start in 2021 and will ...introduce two major challenges for which the tape archive software must be evolved. Firstly the software will need to make more efficient use of tape drives in order to sustain the predicted data rate of 150 petabytes per year as opposed to the current 50 petabytes per year. Secondly the software will need to be seamlessly integrated with EOS, which has become the de facto disk storage system provided by the IT Storage group for physics data. The tape storage software for LHC physics run 3 is code named CTA (the CERN Tape Archive). This paper describes how CTA will introduce a pre-emptive drive scheduler to use tape drives more efficiently, will encapsulate all tape software into a single module that will sit behind one or more EOS systems, and will be simpler by dropping support for obsolete backwards compatibility.
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