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1.
J Med Genet ; 61(2): 186-195, 2024 Jan 19.
Article in English | MEDLINE | ID: mdl-37734845

ABSTRACT

PURPOSE: Genome sequencing (GS) is expected to reduce the diagnostic gap in rare disease genetics. We aimed to evaluate a scalable framework for genome-based analyses 'beyond the exome' in regular care of patients with inherited retinal degeneration (IRD) or inherited optic neuropathy (ION). METHODS: PCR-free short-read GS was performed on 1000 consecutive probands with IRD/ION in routine diagnostics. Complementary whole-blood RNA-sequencing (RNA-seq) was done in a subset of 74 patients. An open-source bioinformatics analysis pipeline was optimised for structural variant (SV) calling and combined RNA/DNA variation interpretation. RESULTS: A definite genetic diagnosis was established in 57.4% of cases. For another 16.7%, variants of uncertain significance were identified in known IRD/ION genes, while the underlying genetic cause remained unresolved in 25.9%. SVs or alterations in non-coding genomic regions made up for 12.7% of the observed variants. The RNA-seq studies supported the classification of two unclear variants. CONCLUSION: GS is feasible in clinical practice and reliably identifies causal variants in a substantial proportion of individuals. GS extends the diagnostic yield to rare non-coding variants and enables precise determination of SVs. The added diagnostic value of RNA-seq is limited by low expression levels of the major IRD disease genes in blood.


Subject(s)
Exome , Eye Diseases , Humans , Prospective Studies , Base Sequence , RNA , Eye Diseases/diagnosis , Eye Diseases/genetics
2.
Hum Mol Genet ; 31(5): 761-774, 2022 03 03.
Article in English | MEDLINE | ID: mdl-34559197

ABSTRACT

Exonic (i.e. coding) variants in genes associated with disease can exert pathogenic effects both at the protein and mRNA level, either by altering the amino acid sequence or by affecting pre-mRNA splicing. The latter is often neglected due to the lack of RNA analyses in genetic diagnostic testing. In this study we considered both pathomechanisms and performed a comprehensive analysis of nine exonic nucleotide changes in OPA1, which is the major gene underlying autosomal dominant optic atrophy (DOA) and is characterized by pronounced allelic heterogeneity. We focused on the GTPase-encoding domain of OPA1, which harbors most of the missense variants associated with DOA. Given that the consensus splice sites extend into the exons, we chose a split codon, namely codon 438, for our analyses. Variants at this codon are the second most common cause of disease in our large cohort of DOA patients harboring disease-causing variants in OPA1. In silico splice predictions, heterologous splice assays, analysis of patient's RNA when available, and protein modeling revealed different molecular outcomes for variants at codon 438. The wildtype aspartate residue at amino acid position 438 is directly involved in the dimerization of OPA1 monomers. We found that six amino acid substitutions at codon 438 (i.e. all substitutions of the first and second nucleotide of the codon) destabilized dimerization while only substitutions of the first nucleotide of the codon caused exon skipping. Our study highlights the value of combining RNA analysis and protein modeling approaches to accurately assign patients to future precision therapies.


Subject(s)
Optic Atrophy, Autosomal Dominant , Codon/genetics , DNA Mutational Analysis , GTP Phosphohydrolases/genetics , Humans , Mutation , Nucleotides , Optic Atrophy, Autosomal Dominant/genetics , Optic Atrophy, Autosomal Dominant/pathology , Pedigree
3.
Microb Cell Fact ; 23(1): 204, 2024 Jul 20.
Article in English | MEDLINE | ID: mdl-39033104

ABSTRACT

The global demand for plant oil has reached unprecedented levels and is relevant in all industrial sectors. Driven by the growing awareness for environmental issues of traditional plant oils and the need for eco-friendly alternatives, microbial oil emerges as a promising product with significant potential. Harnessing the capabilities of oleaginous microorganisms is an innovative approach for achieving sustainable oil production. To increase economic feasibility, it is crucial to explore feedstocks such as agricultural waste streams as renewable resource for microbial bioprocesses. The fungal model Ustilago maydis is one promising organism in the field of microbial triglyceride production. It has the ability to metabolize a wide variety of carbon sources for cell growth and accumulates high amounts of triglycerides intracellularly. In this study we asked whether this large variety of usable carbon sources can also be utilized for triglyceride production, using corn stover saccharides as a showcase.Our experiments revealed metabolization of the major saccharide building blocks present in corn stover, demonstrating the remarkable potential of U. maydis. The microorganism exhibited the capacity to synthesize triglycerides using the saccharides glucose, fructose, sucrose, xylose, arabinose, and galactose as carbon source. Notably, while galactose has been formerly considered as toxic to U. maydis, we found that the fungus can metabolize this saccharide, albeit with an extended lag phase of around 100 hours. We identified two distinct methods to significantly reduce or even prevent this lag phase, challenging previous assumptions and expanding the understanding of U. maydis metabolism.Our findings suggest that the two tested methods can prevent long lag phases on feedstocks with high galactose content and that U. maydis can produce microbial triglycerides very efficiently on many different carbon sources. Looking forward, exploring the metabolic capabilities of U. maydis on additional polymeric components of corn stover and beyond holds promise for innovative applications, marking a significant step toward environmentally sustainable bioprocessing technologies.


Subject(s)
Galactose , Triglycerides , Zea mays , Zea mays/metabolism , Triglycerides/metabolism , Galactose/metabolism , Carbon/metabolism , Ustilago/metabolism , Basidiomycota
4.
Graefes Arch Clin Exp Ophthalmol ; 261(6): 1713-1722, 2023 Jun.
Article in English | MEDLINE | ID: mdl-36645454

ABSTRACT

PURPOSE: To explore the pupil redilation during persistent light exposure (pupillary escape phenomenon) at the macula and periphery with monochromatic light stimuli. METHODS: Forty healthy subjects aged 18-64 years (24 females) were examined by chromatic pupil campimetry (CPC) using red and blue 4-s stimuli of 10° radius at the center and 20°-peripheral locations one per quadrant. One glaucoma patient and one achromatopsia patient served as disease models. For statistical analyses, linear mixed-effects models were performed followed by post hoc t-tests. RESULTS: A distinct pupillary escape could be demonstrated peripherally (blue 0.099%*s, red 0.153%*s); at the central healthy retina, there was no relevant escape, neither for blue nor red stimulation. Comparing central versus peripheral stimulation revealed highly significant differences in the escape (difference blue 0.100 ± 0.013, red 0.144 ± 0.013, < 0.0001, respectively). In the periphery, the escape was significantly more pronounced for red compared with blue stimulation (difference 0.054 ± 0.013; p = 0.0001). Enhanced pupillary escape outside of the 95% confidence interval of the linear mixed-effects model of the healthy population could be exemplarily shown in a patient with glaucomatous ganglion cell damage. In the achromatopsia example, no relevant escape was found for blue stimulation, but for red stimulation in the periphery in a comparable range to healthy controls. CONCLUSION: The results emphasize that an intact inner retinal network of nerve fibers arising from the central macular region is necessary for maintaining pupillary constriction during a bright 4-s light stimulus and preventing increase of pupillary escape. Increasing receptive field sizes towards the periphery on the level of retinal ganglion cells and less input from central 1:1 connections could be one of the driving mechanisms for pupillary escape.


Subject(s)
Color Vision Defects , Glaucoma , Female , Humans , Pupil/physiology , Reflex, Pupillary/physiology , Retina , Photic Stimulation , Light
5.
Graefes Arch Clin Exp Ophthalmol ; 260(2): 577-581, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34554296

ABSTRACT

BACKGROUND/OBJECTIVES: The correct classification of a slowly progressing optic atrophy can be challenging. The aim of this work was to find out if the characteristics of peripapillary retinal nerve fiber layer (RNFL) thickness loss differ between open angle glaucoma (POAG), optic nerve sheath meningioma (ONSM), and sphenoid wing meningioma (SWM). METHODS: A total of 45 patients with POAG, ONSM, and SWM were included in the retrospective study. The peripapillary RNFL thickness measured by spectral-domain optical coherence tomography was analyzed using the Heidelberg Engineering glaucoma module©. RESULTS: Each group consisted of 15 patients. The temporal sector of the RNFL thickness showed a median decrease of - 17 µm in glaucoma patients (range + 6/-34 µm), - 43 µm in ONSM (range - 19/ - 52 µm), and - 44 µm in SWM patients (range - 25/ - 52 µm). The RNFL thickness of the temporal sector of glaucoma patients differed significantly from the other groups (p < 0.001). All other sectors showed no significant difference between the 3 groups. CONCLUSION: The peripapillary RNFL thickness of the temporal sector of patients with beginning to moderate POAG is usually inside normal limits or borderline. In contrast, patients with ONSM and SWM are much more likely to show a considerable reduction in RNFL thickness of the temporal sector. RNFL thickness of the temporal sector marked outside normal limits occurred exclusively in meningioma patients. Considering the presence of this condition as a predictor for meningioma, sensitivity and specificity were 0.8 and 1.0, respectively. In patients with significant reduction in RNFL thickness of the temporal sector, magnetic resonance imaging of the head should be considered to rule out compression of the optic nerves.


Subject(s)
Glaucoma, Open-Angle , Glaucoma , Meningeal Neoplasms , Meningioma , Atrophy , Glaucoma/pathology , Glaucoma, Open-Angle/diagnosis , Glaucoma, Open-Angle/pathology , Humans , Meningeal Neoplasms/complications , Meningeal Neoplasms/diagnosis , Meningioma/complications , Meningioma/diagnosis , Nerve Fibers/pathology , Optic Nerve/pathology , Retrospective Studies , Tomography, Optical Coherence , Visual Fields
6.
Graefes Arch Clin Exp Ophthalmol ; 260(5): 1675-1685, 2022 May.
Article in English | MEDLINE | ID: mdl-34902059

ABSTRACT

PURPOSE: To examine systematically how prechiasmal, chiasmal, and postchiasmal lesions along the visual pathway affect the respective pupillary responses to specific local monochromatic stimuli. METHODS: Chromatic pupil campimetry (CPC) was performed in three patient groups (10 subjects with status after anterior ischemic optic neuropathy, 6 with chiasmal lesions, and 12 with optic tract or occipital lobe lesions (tumor, ischemia)) using red, low-intensity red, and blue local stimuli within the central 30° visual field. Affected areas - as determined by visual field defects revealed using conventional static perimetry - were compared with non-affected areas. Outcome parameters were the relative maximal constriction amplitude (relMCA) and the latency to constriction onset of the pupillary responses. RESULTS: A statistically significant relMCA reduction was observed in the affected areas of postchiasmal lesions with red (p = 0.004) and low-intensity red stimulation (p = 0.001). RelMCA reduction in the affected areas seemed more pronounced for low-intensity red stimulation (46.5% mean reduction compared to non-affected areas; 36% for red stimulation), however statistically not significant. In prechiasmal lesions, a statistically significant latency prolongation could be demonstrated in the affected areas with low-intensity red stimulation (p = 0.015). CONCLUSION: Our results indicate that the choice of stimulus characteristics is relevant in detecting defects in the pupillary pathway of impairment along the visual pathway, favoring red stimuli of low intensity over blue stimuli. Such knowledge opens the door for further fundamental research in pupillary pathways and is important for future clinical application of pupillography in neuro-ophthalmologic patients.


Subject(s)
Pupil Disorders , Visual Pathways , Humans , Photic Stimulation , Pupil/physiology , Pupil Disorders/diagnosis , Reflex, Pupillary/physiology , Visual Field Tests , Visual Fields
7.
Graefes Arch Clin Exp Ophthalmol ; 259(4): 1009-1013, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33337510

ABSTRACT

PURPOSE: In September 2015, the first and so far only medication for treatment of Leber's hereditary optic neuropathy (LHON) was approved in the EU. The drug in question is idebenone (©Raxone) and has been given to all newly diagnosed patients of the University Eye Hospital Tuebingen since the approval of the drug. The aim of the study was to find out whether regular administration of the drug led to an improvement in vision. We retrospectively examined 2 cohorts of consecutive patients with newly occurred visual impairment and LHON diagnosis: One with the initial diagnosis made from January 2010 until April 2014 and a second from October 2015 until January 2020. METHODS: Retrospective, observational cohort study. All electronic medical files of newly diagnosed and genetically confirmed LHON patients of the University Eye Hospital Tuebingen from January 2010 until April 2014 (cohort 1) and October 2015 until January 2020 (cohort 2) with at least 12 months of follow-up examinations have been analyzed. RESULTS: Five patients were included in the first and 7 patients in the second cohort. Patients of cohort 1 received no medication; patients of cohort 2, a daily dose of 900 mg idebenone. The primary visual acuity (VA) ranged between 0.03 and 0.5 in cohort 1 and did not improve during the observation period (median 60 months, range 23-87 months). The patients of cohort 2 have been observed for a median of 23 months (range 12-35 m). The primary VA ranged from 0.01 to 0.16. A recovery in one or both eyes with a final VA from 0.8 to 1.0 was experienced in 3 out of 7 patients. All patients showing a recovery of VA carried the m.11778G>A mutation. CONCLUSION: The observed improvement in the treated cohort may be considered as a hint on the efficacy of idebenone in LHON. The time course of improvement suggests that idebenone should be given 1.5 years in newly diagnosed LHON cases.


Subject(s)
Optic Atrophy, Hereditary, Leber , DNA, Mitochondrial , Humans , Mutation , Optic Atrophy, Hereditary, Leber/diagnosis , Optic Atrophy, Hereditary, Leber/drug therapy , Optic Atrophy, Hereditary, Leber/genetics , Retrospective Studies , Ubiquinone/analogs & derivatives
8.
Exp Eye Res ; 176: 210-218, 2018 11.
Article in English | MEDLINE | ID: mdl-30003883

ABSTRACT

The purpose was to evaluate retinal function by measuring pupillary responses to sinusoidal transcorneal electrostimulation in healthy young human subjects. This work also translates data from analogous in vitro experiments and connects it to the pupillary responses obtained in human experiments. 14 healthy human subjects participated (4 males, 10 females); for the in vitro experiments, two male healthy mouse retinas (adult wild-type C57B/6J) were used. Pupillary responses to sinusoidal transcorneal electrostimulation of varying stimulus carrier frequencies (10, 20 Hz; envelope frequency constantly kept at 1.2 Hz) and intensities (10, 20, 50 µA) were recorded and compared with those obtained with light stimulation (1.2 Hz sinusoidal blue, red light). A strong correlation between the sinusoidal stimulation (electrical as well as light) and the pupillary sinusoidal response was found. The difference between the lag of electrical and light stimulation allowed the estimation of an intensity threshold for pupillary responses to transcorneal electrostimulation (mean ±â€¯SD: 30 ±â€¯10 µA (10 Hz); 38 ±â€¯10 µA (20 Hz)). A comparison between the results of the two stimulation frequencies showed a not statistically significant smaller lag for 10 Hz (10 Hz: 633 ±â€¯90 ms; 20 Hz: 725 ±â€¯178 ms; 50 µA intensity). Analogous in vitro experiments on murine retinas indicated a selective stimulation of photoreceptors and bipolar cells (lower frequencies) and retinal ganglion cells (higher frequencies) and lower stimulation thresholds for the retinal network with sinusoidal compared to pulsatile stimulation - emphasizing that sinusoidal waveforms are well-suited to our purposes. We demonstrate that pupillary responses to sinusoidal transcorneal electrostimulation are measurable as an objective marker in healthy young subjects, even at very low stimulus intensities. By using this unique approach, we unveil the potential for an estimation of the individual intensity threshold and a selective activation of different retinal cell types in humans by varying the stimulation frequency. This technique may have broad clinical utility as well as specific relevance in the monitoring of patients with hereditary retinal disorders, especially as implemented in study protocols for novel therapies, e.g. retinal prostheses or gene therapies.


Subject(s)
Electric Stimulation , Phosphenes/physiology , Reflex, Pupillary/physiology , Retina/physiology , Visual Perception/physiology , Adult , Animals , Cornea/physiology , Female , Healthy Volunteers , Humans , Male , Mice , Mice, Inbred C57BL , Photic Stimulation , Photoreceptor Cells, Vertebrate/physiology , Retinal Bipolar Cells/physiology , Retinal Ganglion Cells/physiology
9.
Graefes Arch Clin Exp Ophthalmol ; 255(3): 519-527, 2017 Mar.
Article in English | MEDLINE | ID: mdl-27785596

ABSTRACT

PURPOSE: To compare the chromatic pupillary light responses (PLR) in healthy subjects with those from patients with diseases of the outer or inner retina under various stimulus conditions, and to ascertain the parameters required to optimally distinguish between disease and control groups. METHODS: Fifteen patients with retinitis pigmentosa (RP), 19 patients with optic nerve disease (ON), and 16 healthy subjects were enrolled in this prospective study. ON included optic neuritis (NNO) and non-arteritic anterior ischemic optic neuropathy (NAION). For each subject, the PLR was recorded, to red, yellow, green, and blue stimuli for durations of 4 and 12 s, and for stimulus intensities of 4 lx and 28 lx. RESULTS: Comparison between control and RP or ON patient results showed that responses after stimulus onset were significantly different for most stimulus conditions, but the post-stimulus amplitudes at 3 s and 7 s after light extinction were not. On the other hand, the difference between the ON and RP groups was significant only for post-stimuli time-points and only for blue stimuli. Differences between responses to blue and red were significantly different, predominantly at post stimulus time-points. A ROC analysis revealed that the maximal constriction amplitudes to a 4 lx, 4 s yellow stimulus are significantly different in ON vs RP patients, and the responses to a 4 s, 28 lx blue stimulus at 7 s post-stimulus are significantly different in controls vs ON vs RP patients with a high specificity. CONCLUSIONS: Pupillary light responses to blue light in healthy, RP, and ON subjects are significantly different from one another. The optimal stimuli for future protocols was found to be a 4 s blue stimulus at 28 lx, and a 4 s yellow stimulus at 4 lx.


Subject(s)
Light , Optic Nerve Diseases/diagnosis , Photoreceptor Cells, Vertebrate/radiation effects , Pupil/radiation effects , Reflex, Pupillary/physiology , Retinitis Pigmentosa/diagnosis , Adult , Aged , Female , Humans , Male , Middle Aged , Optic Nerve Diseases/physiopathology , Photic Stimulation , Prospective Studies , Reflex, Pupillary/radiation effects , Reproducibility of Results , Retinitis Pigmentosa/physiopathology , Young Adult
10.
Invest Ophthalmol Vis Sci ; 65(6): 3, 2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38829669

ABSTRACT

Purpose: Investigating influencing factors on the pupillary light response (PLR) as a biomarker for local retinal function by providing epidemiological data of a large normative collective and to establish a normative database for the evaluation of chromatic pupil campimetry (CPC). Methods: Demographic and ophthalmologic characteristics were captured and PLR parameters of 150 healthy participants (94 women) aged 18 to 79 years (median = 46 years) were measured with L-cone- and rod-favoring CPC protocols. Linear-mixed effects models were performed to determine factors influencing the PLR and optical coherence tomography (OCT) data were correlated with the pupillary function volume. Results: Relative maximal constriction amplitude (relMCA) and latency under L-cone- and rod-favoring stimulation were statistically significantly affected by the stimulus eccentricity (P < 0.0001, respectively). Iris color and gender did not affect relMCA or latency significantly; visual hemifield, season, and daytime showed only minor influence under few stimulus conditions. Age had a statistically significant effect on latency under rod-specific stimulation with a latency prolongation ≥60 years. Under photopic and scotopic conditions, baseline pupil diameter declined significantly with increasing age (P < 0.0001, respectively). Pupillary function volume and OCT data were not correlated relevantly. Conclusions: Stimulus eccentricity had the most relevant impact on relMCA and latency of the PLR during L-cone- and rod-favoring stimulation. Latency is prolonged ≥60 years under scotopic conditions. Considering the large study collective, a representative normative database for relMCA and latency as valid readout parameters for L-cone- and rod-favoring stimulation could be established. This further validates the usability of the PLR in CPC as a biomarker for local retinal function.


Subject(s)
Pupil , Reflex, Pupillary , Tomography, Optical Coherence , Humans , Middle Aged , Female , Male , Adult , Aged , Young Adult , Tomography, Optical Coherence/methods , Pupil/physiology , Adolescent , Reflex, Pupillary/physiology , Biomarkers , Photic Stimulation , Retina/physiology , Retina/diagnostic imaging , Healthy Volunteers , Light , Reference Values
11.
Microbiologyopen ; 11(5): e1324, 2022 10.
Article in English | MEDLINE | ID: mdl-36314761

ABSTRACT

Microbial cocultures are used as a tool to stimulate natural product biosynthesis. However, studies often empirically combine different organisms without a deeper understanding of the population dynamics. As filamentous organisms offer a vast metabolic diversity, we developed a model filamentous coculture of the cellulolytic fungus Trichoderma reesei RUT-C30 and the noncellulolytic bacterium Streptomyces coelicolor A3(2). The coculture was set up to use α-cellulose as a carbon source. This established a dependency of S. coelicolor on hydrolysate sugars released by T. reesei cellulases. To provide detailed insight into coculture dynamics, we applied high-throughput online monitoring of the respiration rate and fluorescence of the tagged strains. The respiration rate allowed us to distinguish the conditions of successful cellulase formation. Furthermore, to dissect the individual strain contributions, T. reesei and S. coelicolor were tagged with mCherry and mNeonGreen (mNG) fluorescence proteins, respectively. When evaluating varying inoculation ratios, it was observed that both partners outcompete the other when given a high inoculation advantage. Nonetheless, adequate proportions for simultaneous growth of both partners, cellulase, and pigment production could be determined. Finally, population dynamics were also tuned by modulating abiotic factors. Increased osmolality provided a growth advantage to S. coelicolor. In contrast, an increase in shaking frequency had a negative effect on S. coelicolor biomass formation, promoting T. reesei. This comprehensive analysis fills important knowledge gaps in the control of complex cocultures and accelerates the setup of other tailor-made coculture bioprocesses.


Subject(s)
Cellulase , Trichoderma , Cellulase/metabolism , Coculture Techniques , Cellulose/metabolism , Population Dynamics
12.
Phys Rev E ; 102(4-1): 042308, 2020 Oct.
Article in English | MEDLINE | ID: mdl-33212607

ABSTRACT

We analyze the late-time relaxation dynamics for a general contagion model. In this model, nodes are either active or failed. Active nodes can fail either "spontaneously" at any time or "externally" if their neighborhoods are sufficiently damaged. Failed nodes may always recover spontaneously. At late times, the breaking of time-translation invariance is a necessary condition for physical aging. We observe that time-translational invariance is lost for initial conditions that lie between the basins of attraction of the model's two stable stationary states. Based on corresponding mean-field predictions, we characterize the observed model behavior in terms of a phase diagram spanned by the fractions of spontaneously and externally failed nodes. For the square lattice, the phases in which the dynamics approaches one of the two stable stationary states are not linearly separable due to spatial correlation effects. Our results provide insights into aging and relaxation phenomena that are observable in a model of social contagion processes.

13.
Medizinhist J ; 43(1): 20-55, 2008.
Article in German | MEDLINE | ID: mdl-18664012

ABSTRACT

During World War II, psychiatric patients hospitalized in asylums in Eastern Prussia became victims of two separate killing programmes: first, by the SS-special command Lange, second by the centrally (in Berlin) organized "euthanasia"-"Aktion T4". By an analysis of the patient files of the victims, the present paper shows that the historical actors responsible for the killings were communicating with each other. It is now also possible to reconstruct the exact dynamic in time and space of the killings. A comparative analysis of the selection criteria within the total population of the asylums documents that in both programs, the responsible historical actors included physicians and provincial administrative personnel; it further shows that under the conditions of war, only patients who were able to contribute to the asylum work and economy, and were behaviourally adapted could survive.


Subject(s)
Euthanasia/history , Hospitals, Psychiatric/history , Mental Disorders/history , National Socialism/history , Germany , History, 20th Century , Holocaust/history , Humans , Mentally Ill Persons/history , World War II
14.
Biomed Tech (Berl) ; 63(6): 729-734, 2018 Nov 27.
Article in English | MEDLINE | ID: mdl-29369809

ABSTRACT

Pupillographic campimetry allows measuring the visual field objectively by analyzing the pupil response to perimetric stimuli. One of the drawbacks of this technique, similar to static perimetry, is the need of reliable fixation of the subject. By using stimulus sizes comparable to static perimetry and applying gaze tracking, we enable a retinotopic visual field examination regardless of fixation problems and with an increased stability and improved spatial resolution. Here, we present the results of applying the method in eight normal sighted subjects as well as in three patients suffering from diseases usually diagnosed by perimetry. The results in normal sighted subjects show a reduction in the amplitude of the pupil response with increasing eccentricity as expected. We also demonstrate that gaze-controlled campimetry is able to detect organic visual field defects objectively in a patient group and classify the visual field defects without an organic background. Moreover, we show that our method is able to evaluate the visual field sensitivity loss beyond classical perimetry in patients with late-stage retinitis pigmentosa. Thus, gaze-controlled pupil campimetry can be used in addition to classical perimetry, allowing for an objective monitoring of disease progression, rendering it as a biomarker for novel treatments.


Subject(s)
Pupil/physiology , Vision Disorders/physiopathology , Visual Field Tests , Diagnostic Techniques, Ophthalmological , Humans
15.
Sci Rep ; 7(1): 10283, 2017 08 31.
Article in English | MEDLINE | ID: mdl-28860657

ABSTRACT

Covertly shifting attention to a brighter or darker image (without moving one's eyes) is sufficient to evoke pupillary constriction or dilation, respectively. One possibility is that this attentional modulation involves the pupillary light response pathway, which pivots around the olivary pretectal nucleus. We investigate this possibility by studying patients with Parinaud's syndrome, where the normal pupillary light response is strongly impaired due to lesions in the pretectal area. Four patients and nine control participants covertly attended (while maintaining fixation at the center of a monitor screen) to one of two disks located in the left and right periphery: one brighter, the other darker than the background. Patients and control subjects behaved alike, showing smaller pupils when attending to the brighter stimulus (despite no eye movements); consistent results were obtained with a dynamic version of the stimulus. We interpret this as proof of principle that attention to bright or dark stimuli can dynamically modulate pupil size in patients with Parinaud's syndrome, suggesting that attention acts independently of the pretectal circuit for the pupillary light response and indicating that several components of the pupillary response can be isolated - including one related to the focus of covert attention.


Subject(s)
Pupil/physiology , Reflex, Pupillary , Adult , Attention , Female , Fixation, Ocular , Humans , Light , Male , Middle Aged , Ocular Motility Disorders/diagnosis , Ocular Motility Disorders/physiopathology , Ocular Motility Disorders/therapy , Reflex, Pupillary/radiation effects
16.
Invest Ophthalmol Vis Sci ; 58(2): 1274-1282, 2017 02 01.
Article in English | MEDLINE | ID: mdl-28241315

ABSTRACT

Purpose: To establish a feasible and sensitive pupillographic protocol to assess outer and inner retinal function for the first gene therapy trial in achromatopsia patients (ACHM) with mutations in CNGA3. Methods: Twenty-seven CNGA3-ACHM patients and 22 age-matched control subjects were tested using chromatic pupillography. Three different protocols were established to assess the pupillary light reflex parameters and to create the final protocol. In the individual protocols, various stimulus parameters (i.e., intensity, duration, wavelength, adaptation states) were applied to evaluate the impact of these stimuli on the pupillary response in untreated ACHM patients. Results: In the light-adapted conditions, CNGA3-ACHM patients showed significantly reduced maximal amplitudes compared with the control group when using a 1-second high intensity (28-lux corneal illumination) blue or red stimulus (P < 0.005). In the dark-adapted conditions, CNGA3-ACHM patients unexpectedly revealed significantly increased maximal amplitudes when stimulating with red (1 second) or blue (4 ms and 1 second) stimuli of low intensity (0.01-lux corneal illumination; P < 0.05). Pupil responses of CNGA3-ACHM patients after high intensity (28 lux) red and blue 1-second stimuli were within the normal range. Conclusions: Chromatic pupillography demonstrated significant reduced pupil responses to stimuli addressing primarily cone function, an increased sensitivity to rod-favoring stimuli and evidence for disinhibition of intrinsically photosensitive retinal ganglion cells in CNGA3-ACHM patients. A final protocol was established based on these findings. These conclusions may be useful for the objective assessment of efficacy gained by gene therapy or other innovative interventions in this hereditary retinal disorder.


Subject(s)
Color Vision Defects/therapy , Diagnostic Techniques, Ophthalmological , Genetic Therapy , Reflex, Pupillary/physiology , Adult , Case-Control Studies , Clinical Protocols , Color Vision Defects/physiopathology , Dark Adaptation/physiology , Female , Humans , Light , Male , Middle Aged , Photic Stimulation/methods , Young Adult
17.
PLoS One ; 12(11): e0188899, 2017.
Article in English | MEDLINE | ID: mdl-29190672

ABSTRACT

PURPOSE: To evaluate the safety and tolerability of intravitreal ISTH0036, an antisense oligonucleotide selectively targeting transforming growth factor beta 2 (TGF-ß2), in patients with primary open angle glaucoma (POAG) undergoing trabeculectomy (TE; glaucoma filtration surgery). METHODS: In this prospective phase I trial glaucoma patients scheduled for TE with mitomycin C (MMC) received a single intravitreal injection of ISTH0036 at the end of surgery in escalating total doses of 6.75 µg, 22.5 µg, 67.5 µg or 225 µg, resulting in calculated intraocular ISTH0036 concentrations in the vitreous humor of approximately 0.3 µM, 1 µM, 3 µM or 10 µM after injection, respectively. Outcomes assessed included: type and frequency of adverse events (AEs), intraocular pressure (IOP), numbers of interventions post trabeculectomy, bleb survival, visual acuity, visual field, electroretinogram (ERG), slit lamp biomicroscopy and optic disc assessment. RESULTS: In total, 12 patients were treated in the 4 dose groups. Main ocular AEs observed were corneal erosion, corneal epithelium defect, or too high or too low IOP, among others. No AE was reported to be related to ISTH0036. All other safety-related analyses did not reveal any toxicities of concern, either. The mean medicated preoperative IOP at decision time-point for surgery was 27.3 mmHg +/- 12.6 mmHg (SD). Mean IOP (±SD) for dose levels 1, 2, 3, and 4 were at Day 43 9.8 mmHg ± 1.0 mmHg, 11.3 mmHg ± 6.7 mmHg, 5.5 mmHg ± 3.0 mmHg and 7.5 mmHg ± 2.3 mmHg SD; and at Day 85 9.7 mmHg ± 3.3 mmHg, 14.2 mmHg ± 6.5 mmHg, 5.8 mmHg ± 1.8 mmHg and 7.8 mmHg ± 0.6 mmHg, respectively. In contrast to IOP values for dose levels 1 and 2, IOP values for dose levels 3 and 4 persistently remained below 10 mmHg throughout the observation period. CONCLUSION: This first-in-human trial demonstrates that intravitreal injection of ISTH0036 at the end of TE is safe. Regarding IOP control, single-dose ISTH0036 administration of 67.5 µg or 225 µg at the time of TE resulted in IOP values persistently < 10 mmHg over the three month postoperative observation period.


Subject(s)
Glaucoma Drainage Implants , Glaucoma, Open-Angle/drug therapy , Oligonucleotides, Antisense/therapeutic use , Oligonucleotides/therapeutic use , Aged , Female , Glaucoma, Open-Angle/surgery , Humans , Male , Middle Aged , Oligonucleotides/adverse effects , Oligonucleotides/pharmacology , Oligonucleotides, Antisense/adverse effects , Oligonucleotides, Antisense/pharmacology , Prospective Studies , Transforming Growth Factors
18.
Eur J Endocrinol ; 172(4): 415-22, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25599706

ABSTRACT

OBJECTIVE: Thresholds of 2-20 hounsfield units (HU) in unenhanced computed tomography (CT) are suggested to discriminate benign adrenal tumors (BATs) from malignant adrenal tumors. However, these studies included only low numbers of adrenocortical carcinomas (ACCs). This study defines a HU threshold by inclusion of a large cohort of ACCs. DESIGN: Retrospective, blinded, comparative analysis of CT scans from 51 patients with ACCs (30 females, median age 49 years) and 25 patients with BATs (12 females, median age 64 years) diagnosed during the period of 2005-2010 was performed. METHODS: Tumor density was evaluated in unenhanced CT by two blinded investigators. RESULTS: Median tumor size was 9 cm (range 2.0-20) for ACCs vs 4 cm (2.0-7.5) for BATs (P<0.0001). In ACCs, the median unenhanced HU value was 34 (range 14-74) in comparison with 5 (-13 to 40) in BATs (P<0.0001). ROC analysis revealed a HU of 21 as threshold with the best diagnostic accuracy (sensitivity 96%, specificity 80%, and AUC 0.89). However, two ACCs that were 5 and 6 cm in size would have been missed. Setting the threshold to 13.9 allowed for 100% sensitivity, but a lower specificity of 68%. CONCLUSIONS: This first large study on ACCs confirmed that the vast majority of ACCs have unenhanced HU >21. However, to avoid misdiagnosing an ACC as benign, a threshold of 13 should be used.


Subject(s)
Adrenal Cortex Neoplasms/diagnostic imaging , Adrenocortical Adenoma/diagnostic imaging , Adrenocortical Carcinoma/diagnostic imaging , Tomography, X-Ray Computed/methods , Adolescent , Adrenal Cortex Neoplasms/epidemiology , Adrenal Cortex Neoplasms/pathology , Adrenocortical Adenoma/epidemiology , Adrenocortical Adenoma/pathology , Adrenocortical Carcinoma/epidemiology , Adrenocortical Carcinoma/pathology , Adult , Aged , Aged, 80 and over , Diagnosis, Differential , Female , Germany/epidemiology , Humans , Male , Middle Aged , Registries , Retrospective Studies , Young Adult
19.
Plast Reconstr Surg ; 120(7): 1796-1807, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18090741

ABSTRACT

BACKGROUND: The authors investigated in nonhuman primates (Papio ursinus) whether it is possible to engineer biomimetic matrices that induce the differentiation of osteoblastic cells expressing selected osteogenic mRNA species of the transforming growth factor (TGF)-beta superfamily. METHODS: Four types of sintered hydroxyapatite and biphasic hydroxyapatite/tricalcium phosphate bioceramics were evaluated as osteoinductive self-inducing biomimetic matrices. Matrices were fabricated with a series of repetitive concavities that initiate the induction of bone formation as a secondary response. Single-phase hydroxyapatite, biphasic hydroxyapatite/tricalcium phosphate, and carbon-impregnated single-phase hydroxyapatite, the latter with fine and coarse porosities, were implanted heterotopically in the rectus abdominis. Specimens for orthotopic calvarial implantation were a total of 16 macroporous disks 25 mm in diameter of single-phase hydroxyapatite and biphasic hydroxyapatite/tricalcium phosphate. RESULTS: Heterotopic specimens 90 and 180 days after implantation showed the induction of bone within concavities of the biomimetic matrices. Northern blot analyses of heterotopic specimens showed that carbon-impregnated single-phase hydroxyapatite specimens induced high expression of osteogenic protein-1 mRNA, correlating with the induction of bone formation. Collagen type IV mRNA was highly expressed, particularly on day 90, by all the implanted matrices. Orthotopic specimens showed substantial bone formation across the implanted constructs. CONCLUSIONS: Self-induced bone has been achieved via the deployment of osteogenic molecular signals expressed by differentiating osteoblastic-like cells, later secreted and embedded into the smart concavities of the biomimetic matrices. The described biomimetic matrices induce de novo bone formation even in the absence of exogenously applied osteogenic proteins of the TGF-beta superfamily.


Subject(s)
Ceramics , Implants, Experimental , Osseointegration , Osteoblasts/cytology , Tissue Scaffolds , Animals , Bone Morphogenetic Protein 7 , Bone Morphogenetic Proteins/biosynthesis , Bone Morphogenetic Proteins/genetics , Calcium Phosphates , Carbon , Collagen Type IV/biosynthesis , Collagen Type IV/genetics , Durapatite , Equipment Design , Male , Materials Testing , Morphogenesis , Neovascularization, Physiologic , Osteoblasts/metabolism , Papio ursinus , Porosity , RNA, Messenger/biosynthesis , Rectus Abdominis/surgery , Skull/surgery , Transforming Growth Factor beta/biosynthesis , Transforming Growth Factor beta/genetics
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