Associations between OPA1, MFN1, and MFN2 polymorphisms and primary open angle glaucoma in Polish participants of European ancestry.

BACKGROUND: Glaucomatous optic nerve damage is caused by selective death of retinal ganglion cells (RGCs). Another condition with underlying loss of RGCs is autosomal dominant optic atrophy (ADOA). Majority of ADOA patients have mutations in OPA1, gene responsible for mitochondrial fusion final steps. Clinical resemblance between the two diseases make genes involved in mitochondrial fusion good candidates as glaucoma genes. In this study, we investigated if selected polymorphisms of OPA1, MFN1, and MFN2 were associated with glaucoma in Polish population. METHODS: Four OPA1 (rs166850, rs10451941, rs7624750, rs9851685), one MFN1 (rs2111534), and two MFN2 (rs873458, rs2295281) single nucleotide polymorphisms were investigated in 304 primary open angle glaucoma patients (204 with normal tension glaucoma, 100 with high-tension glaucoma) and 258 control subjects using RT-PCR method. RESULTS: There was a significant difference in genotype frequencies of rs9851685 and rs2111534 polymorphisms between glaucoma patients and control subjects. Several genotype combinations comprising SNPs at OPA1 and MFN1 were significantly differently distributed in a three-way comparison between controls, patients with NTG and patients with HTG. None of the studied MFN2 polymorphisms was significantly associated with HTG or NTG. CONCLUSIONS: In studied population, genotype CC and allele C of rs9851685 OPA1 polymorphism are NTG risk factors, whereas TT genotype and T allele of this polymorphism are protective factors against NTG. Genotype GA of rs2111534 MFN1 polymorphism is an HTG risk factor and AA genotype of this polymorphism is a protective factor against HTG. Several OPA1 and MFN2 genotype combinations are significantly associated with either increased or decreased risk of glaucoma in this population.

Clinical Features of Pseudoexfoliative Glaucoma in Treated Polish Patients.

PURPOSE: The aim of this study was to describe clinical characteristics of glaucomatous optic neuropathy in treated Polish patients with pseudoexfoliative glaucoma. METHODS: In the course of the study, 348 eyes of 231 patients with pseudoexfoliative glaucoma. The patients involved in the study were treated in the Department of Diagnostic and Microsurgery of Glaucoma in Lublin between 2012 and 2019. The following parameters were assessed in the examination: visual acuity, slit-lamp biomicroscopy with evaluation of anterior segment of the eye, gonioscopic examination, stereoscopic fundus examination of the eye, intraocular pressure, visual field, and pachymetry. RESULTS: The mean age of all the patients was 73.16 years (SD±8.03). The mean age of women was 74.06 (SD±6.97), and the mean age of men was 71.8 (SD±8.51, p=0.006265). Women represented 37.93% (n=132) of the studied group, while men 62.07% (n=216). In the group of patients younger than 65 years of age, 27.9% were male and 15% female (p=0.0021). In the whole studied group, mean peak IOP was 29.25 mmHg with higher mean values in male patients (M vs F: 33.24 mmHg vs 26.86 mmHg; p=0.000). Peak values exceeding 30 mmHg were significantly more frequent in males (M vs F: 56.5% vs 31.9%; p=0.0000). Peak IOP never exceeding 21 mmHg was observed in 18.6% of the patients. The mean value of MD (Mean Deviation) was -12.85 dB in the whole group. The men were more likely to have more advanced glaucoma, according to MD (M vs F: -16.35 dB vs -11.13 dB; p=0.0000). CONCLUSION: Pseudoexfoliative glaucoma was more frequently observed in men with younger age, higher IOP, and more advanced glaucoma. Normotensive glaucoma was observed in 18.6% of the patients with pseudoexfoliative glaucoma.

The quality of life of farmers with chronic obstructive pulmonary disease (COPD).

Introduction and objective. COPD is a medical state characterized by chronically poor airflow, and typically worsens over time. Farmers have an increased risk of COPD because of being exposed to ammonia, hydrogen sulfide, inorganic dust, and organic dust. The quality of life of the ill depends on biomedical as well as psychosocial factors, the impact of which has not been a frequent subject of studies among COPD patients. The aim of the study was to indicate the factors that have negative and positive influence on the quality of life of farmers suffering from COPD. Materials and method. The study was conducted among 84 farmers treated for COPD in the Department of Pneumology, Oncology and Allergology of the Medical University in Lublin, Poland. The differences between the farmers concerned: severity of the disease, level of education and income, frequency of smoking tobacco and drinking alcohol, kinds of support they receive from their families, and the level of depression and anxiety experienced by the patients. Results. The study revealed that most patients suffered from depressive and anxiety disorders, and the level of depression higher among the patients who smoked more. Lack of family support had significant influence on exacerbation of the patient's depressive and anxiety symptoms. Patients who had recently experienced a critical situation presented with more severe COPD symptoms, lower quality of life and a higher level of depression. Higher income of the patients had positive influence on their quality of life. Farmers addicted to alcohol suffered from a higher level of anxiety.

Seizures Start without Common Signatures of Critical Transition.

Complex dynamical systems may exhibit sudden autonomous changes from one state to another. Such changes that occur rapidly in comparison to the regular dynamics have been termed critical transitions. Examples of such phenomena can be found in many complex systems: changes in climate and ocean circulation, changes in wildlife populations, financial crashes, as well as in medical conditions like asthma attacks and depression. It has been recognized that critical transitions, even if they arise in completely different contexts and situations, share several common attributes and also generic early-warning signals that indicate that a critical transition is approaching. In the present study, we review briefly the general characteristics that have been observed in systems prior to critical transitions and apply these general indicators to nearly 300 epileptic seizures collected from human subjects using invasive EEG. Only in about 8% of the patients was evidence of critical transitions found. In the remaining majority of cases no early warning signals that behaved consistently prior to seizures were observed. These results do not rule out the possibility of critical transitions to seizure but point to limited relevance of their early warning signals in the context of human epilepsy observed using intracranial EEG recordings.

Towards an optimization of stimulus parameters for brain-computer interfaces based on steady state visual evoked potentials.

Efforts to construct an effective brain-computer interface (BCI) system based on Steady State Visual Evoked Potentials (SSVEP) commonly focus on sophisticated mathematical methods for data analysis. The role of different stimulus features in evoking strong SSVEP is less often considered and the knowledge on the optimal stimulus properties is still fragmentary. The goal of this study was to provide insight into the influence of stimulus characteristics on the magnitude of SSVEP response. Five stimuli parameters were tested: size, distance, colour, shape, and presence of a fixation point in the middle of each flickering field. The stimuli were presented on four squares on LCD screen, with each square highlighted by LEDs flickering with different frequencies. Brighter colours and larger dimensions of flickering fields resulted in a significantly stronger SSVEP response. The distance between stimulation fields and the presence or absence of the fixation point had no significant effect on the response. Contrary to a popular belief, these results suggest that absence of the fixation point does not reduce the magnitude of SSVEP response. However, some parameters of the stimuli such as colour and the size of the flickering field play an important role in evoking SSVEP response, which indicates that stimuli rendering is an important factor in building effective SSVEP based BCI systems.

A high frequency steady-state visually evoked potential based brain computer interface using consumer-grade EEG headset.

This work evaluates a possibility of creating a high-frequency, SSVEP-based brain computer interface using a low cost EEG recording hardware - an Emotiv EEG Neuro-headset. Both above aspects are crucial to enable deploying the BCI technology in the consumer market. High frequencies can be used to create a non-tiring and more pleasant interface. Commercial EEG systems, as the Emotiv EEG, although demonstrating large underperformance, are much more affordable than standard, clinical-grade EEG amplifiers. A system classifying between two stimuli and rest is designed and tested in two experiments: on five and ten subject respectively. First, the accuracy of the system is compared for frequencies in lower range (17Hz, 19Hz, 23Hz, 25Hz) and higher range (31Hz, 33Hz, 37Hz, 40Hz). The mean online accuracy is 80%±15% for the former and 67%±12% for the latter. Second, a more thorough investigation is done by evaluating the system for frequencies within a set of 35Hz-40Hz. Although the mean accuracy, 64% ± 22%, is relatively low, most of the users were able to achieve satisfying accuracy, with the mean reaching 82%±5%, which would allow for an efficient, and yet pleasant, usage of the BCI system. In each case a user dependent approach is applied, with a calibration session lasting about five minutes. EEG feature extraction is done using common spatial pattern (CSP) filtering, canonical correlation analysis (CCA), and linear discrimination analysis (LDA).

On the quantification of SSVEP frequency responses in human EEG in realistic BCI conditions.

This article concerns one of the most important problems of brain-computer interfaces (BCI) based on Steady State Visual Evoked Potentials (SSVEP), that is the selection of the a-priori most suitable frequencies for stimulation. Previous works related to this problem were done either with measuring systems that have little in common with actual BCI systems (e.g., single flashing LED) or were presented on a small number of subjects, or the tested frequency range did not cover a broad spectrum. Their results indicate a strong SSVEP response around 10 Hz, in the range 13-25 Hz, and at high frequencies in the band of 40-60 Hz. In the case of BCI interfaces, stimulation with frequencies from various ranges are used. The frequencies are often adapted for each user separately. The selection of these frequencies, however, was not yet justified in quantitative group-level study with proper statistical account for inter-subject variability. The aim of this study is to determine the SSVEP response curve, that is, the magnitude of the evoked signal as a function of frequency. The SSVEP response was induced in conditions as close as possible to the actual BCI system, using a wide range of frequencies (5-30 Hz, in step of 1 Hz). The data were obtained for 10 subjects. SSVEP curves for individual subjects and the population curve was determined. Statistical analysis were conducted both on the level of individual subjects and for the group. The main result of the study is the identification of the optimal range of frequencies, which is 12-18 Hz, for the registration of SSVEP phenomena. The applied criterion of optimality was: to find the largest contiguous range of frequencies yielding the strong and constant-level SSVEP response.

The presence of HER2 exon 20 insertion in patients with central nervous system metastases from non-small lung cancer--a potential application in classification for therapy.

INTRODUCTION: HER2 (ErbB2/neu) is a member of the ErbB family of four structurally related receptors of tyrosine kinase activity. Overexpression of ErbB-1 (EGFR) and HER2 is found in many human cancers, but the presence of these genes mutations determines the effectiveness of EGFR and HER2 tyrosine kinase inhibitors in the therapy of non-small cell lung cancer (NSCLC). MATERIAL AND METHODS: To search for insertions of the HER2 gene in exon 20 in 150 brain metastases of non-small cell lung cancer patients, we used a PCR technique based on analysis of amplified DNA fragment lengths. We also compared the HER2 mutational status with clinicopathologic features and the presence of EGFR and BRAF mutations. RESULTS: HER2 mutation was present in one male, non-smoking patient with low differentiated adenocarcinoma (0.67% of all patients and 1.5% of patients with adenocarcinoma). The mutations of EGFR and BRAF genes were not found in HER2-mutated patient. CONCLUSIONS: The literature data suggests that patients with HER2 mutations may be sensitive to tyrosine kinase inhibitors of both EGFR and HER2 receptors (e.g. afatinib). Therefore, the identification of new driver mutations in NSCLC can improve the quality of patient care by enabling the use of correct molecularly targeted therapies.