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Inner ear balance problems are common worldwide and are often difficult to diagnose. In this study we examine the classification of patients with inner ear balance problems and controls (people not suffering from inner ear balance problems) based on data derived from the stabilogram signals and using machine learning algorithms. This paper is a continuation for our earlier paper where the same dataset was used and the focus was medically oriented. Our collected dataset consists of stabilogram (a force platform response) data from 30 patients suffering from Ménière's disease and 30 students called controls. We select a wide variety of machine learning algorithms from traditional baseline methods to state-of-the-art methods such as Least-Squares Support Vector Machines and Random Forests. We perform extensive and carefully made parameter value searches and we are able to achieve 88.3% accuracy using k -nearest neighbor classifier. Our results show that machine learning algorithms are well capable of separating patients and controls from each other. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to examine how well the human induced pluripotent stem cell (hiPSC) colony images can be classified using error-correcting output codes (ECOC). Our image dataset includes hiPSC colony images from three classes (bad, semigood, and good) which makes our classification task a multiclass problem. ECOC is a general framework to model multiclass classification problems. We focus on four different coding designs of ECOC and apply to each one of them k-Nearest Neighbor (k-NN) searching, naïve Bayes, classification tree, and discriminant analysis variants classifiers. We use Scaled Invariant Feature Transformation (SIFT) based features in classification. The best accuracy (62.4%) is obtained with ternary complete ECOC coding design and k-NN classifier (standardized Euclidean distance measure and inverse weighting). The best result is comparable with our earlier research. The quality identification of hiPSC colony images is an essential problem to be solved before hiPSCs can be used in practice in large-scale. ECOC methods examined are promising techniques for solving this challenging problem. [ABSTRACT FROM AUTHOR]

Hypertrophic cardiomyopathy (HCM) is a genetic cardiac disease, which affects the structure of heart muscle tissue. The clinical symptoms include arrhythmias, progressive heart failure, and even sudden cardiac death but the mutation carrier can also be totally asymptomatic. To date, over 1400 mutations have been linked to HCM, mostly in genes encoding for sarcomeric proteins. However, the pathophysiological mechanisms of the disease are still largely unknown. Two founder mutations for HCM in Finland are located in myosin-binding protein C (MYBPC3-Gln1061X) and α-tropomyosin (TPM1-Asp175Asn) genes. We studied the properties of HCM cardiomyocytes (CMs) derived from patient-specific human induced pluripotent stem cells (hiPSCs) carrying either MYBPC3-Gln1061X or TPM1-Asp175Asn mutation. Both types of HCM-CMs displayed pathological phenotype of HCM but, more importantly, we found differences between CMs carrying either MYBPC3-Gln1061X or TPM1-Asp175Asn gene mutation in their cellular size, Ca2+ handling, and electrophysiological properties, as well as their gene expression profiles. These findings suggest that even though the clinical phenotypes of the patients carrying either MYBPC3-Gln1061X or TPM1-Asp175Asn gene mutation are similar, the genetic background as well as the functional properties on the cellular level might be different, indicating that the pathophysiological mechanisms behind the two mutations would be divergent as well. [ABSTRACT FROM AUTHOR]

Hypertrophic cardiomyopathy (HCM) is a genetic cardiac disease, which affects the structure of heart muscle tissue. The clinical symptoms include arrhythmias, progressive heart failure, and even sudden cardiac death but the mutation carrier can also be totally asymptomatic. To date, over 1400 mutations have been linked to HCM, mostly in genes encoding for sarcomeric proteins. However, the pathophysiological mechanisms of the disease are still largely unknown. Two founder mutations for HCM in Finland are located in myosin-binding protein C (MYBPC3-Gln1061X) and α-tropomyosin (TPM1-Asp175Asn) genes. We studied the properties of HCM cardiomyocytes (CMs) derived from patient-specific human induced pluripotent stem cells (hiPSCs) carrying either MYBPC3-Gln1061X or TPM1-Asp175Asn mutation. Both types of HCM-CMs displayed pathological phenotype of HCM but, more importantly, we found differences between CMs carrying either MYBPC3-Gln1061X or TPM1-Asp175Asn gene mutation in their cellular size, Ca2+ handling, and electrophysiological properties, as well as their gene expression profiles. These findings suggest that even though the clinical phenotypes of the patients carrying either MYBPC3-Gln1061X or TPM1-Asp175Asn gene mutation are similar, the genetic background as well as the functional properties on the cellular level might be different, indicating that the pathophysiological mechanisms behind the two mutations would be divergent as well. [ABSTRACT FROM AUTHOR]

Background: Orientation and the degree of isotropy are important in many biological systems such as the sarcomeres of cardiomyocytes and other fibrillar structures of the cytoskeleton. Image based analysis of such structures is often limited to qualitative evaluation by human experts, hampering the throughput, repeatability and reliability of the analyses. Software tools are not readily available for this purpose and the existing methods typically rely at least partly on manual operation. Results: We developed CytoSpectre, an automated tool based on spectral analysis, allowing the quantification of orientation and also size distributions of structures in microscopy images. CytoSpectre utilizes the Fourier transform to estimate the power spectrum of an image and based on the spectrum, computes parameter values describing, among others, the mean orientation, isotropy and size of target structures. The analysis can be further tuned to focus on targets of particular size at cellular or subcellular scales. The software can be operated via a graphical user interface without any programming expertise. We analyzed the performance of CytoSpectre by extensive simulations using artificial images, by benchmarking against FibrilTool and by comparisons with manual measurements performed for real images by a panel of human experts. The software was found to be tolerant against noise and blurring and superior to FibrilTool when analyzing realistic targets with degraded image quality. The analysis of real images indicated general good agreement between computational and manual results while also revealing notable expert-to-expert variation. Moreover, the experiment showed that CytoSpectre can handle images obtained of different cell types using different microscopy techniques. Finally, we studied the effect of mechanical stretching on cardiomyocytes to demonstrate the software in an actual experiment and observed changes in cellular orientation in response to stretching. Conclusions: CytoSpectre, a versatile, easy-to-use software tool for spectral analysis of microscopy images was developed. The tool is compatible with most 2D images and can be used to analyze targets at different scales. We expect the tool to be useful in diverse applications dealing with structures whose orientation and size distributions are of interest. While designed for the biological field, the software could also be useful in non-biological applications. [ABSTRACT FROM AUTHOR]

Objective: To explore the impact, reactions and coping methods of the significant others (SOs) of people with Ménière's disease (MD). Design: SOs of people with MD were asked to answer open-ended questions reporting the ' life effects' and ' positive experiences' they have had as a result of the partner's condition. The replies to the ' life effects' question was categorized using the WHO-ICF framework. The responses of ' life effects' from this study and the ' positive experiences' reported in a recent study (Manchaiah et al, 2013) were evaluated with K-means clustering analysis. Study sample: Eighty-eight SOs (42 male, 42 female, and four did not state gender). Results: While the SOs mainly listed their own problems, a significant number of responses related to the problems of their partner. Personal perspectives tended to focus on the consequences of their partner's condition, whereas in perspectives of their partner they focussed on his/her symptoms. Further, replies from 81 SOs were used in evaluation of responses and were classified into four categories: constrained life attitude; disease burden attitude; care and support attitude; and social isolation attitude. Conclusions: The results of this study support the importance of including the SO of people with MD in the rehabilitation process. [ABSTRACT FROM AUTHOR]

Objective: To explore the impact, reactions and coping methods of the significant others (SOs) of people with Ménière's disease (MD). Design: SOs of people with MD were asked to answer open-ended questions reporting the ' life effects' and ' positive experiences' they have had as a result of the partner's condition. The replies to the ' life effects' question was categorized using the WHO-ICF framework. The responses of ' life effects' from this study and the ' positive experiences' reported in a recent study (Manchaiah et al, 2013) were evaluated with K-means clustering analysis. Study sample: Eighty-eight SOs (42 male, 42 female, and four did not state gender). Results: While the SOs mainly listed their own problems, a significant number of responses related to the problems of their partner. Personal perspectives tended to focus on the consequences of their partner's condition, whereas in perspectives of their partner they focussed on his/her symptoms. Further, replies from 81 SOs were used in evaluation of responses and were classified into four categories: constrained life attitude; disease burden attitude; care and support attitude; and social isolation attitude. Conclusions: The results of this study support the importance of including the SO of people with MD in the rehabilitation process. [ABSTRACT FROM AUTHOR]

Objective: Aural fullness in Ménière's disease and the predisposing and consequential factors were investigated and possible consequences of aural fullness on participation activity were explored. Methods: 726 subjects of the Finnish Ménière Association replied to a questionnaire focusing on symptoms of Ménière's disease, sense of coherence, attitude, participation restriction, and general health-related quality of life (EQ-5D). In the analysis, the severity of the disease was controlled. Results: 68% of the subjects had aural fullness and in 37% it was moderate or strong. Aural fullness was rated as the worst problem by 4.4% of the subjects. Females reported more aural fullness than males. Tinnitus, hyperacusis and balance problems were significant predictors of aural fullness. Aural fullness was associated with reduced quality of life and complaints such as vertigo attacks, balance problems and hearing loss. Analysis based on participation restriction indicated that severe aural fullness leads to social isolation. Conclusions: Largely, psychological factors and personal traits modify problems experienced by aural fullness. Relaxation was the only statistically significant method that alleviated aural fullness. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Objective: To explore the role of fatigue and its predisposing and consequential factors and consequences, on quality of life and social participation. Subjects and methods: A questionnaire survey of 728 members of the Finnish Ménière Association was performed. Questions focused on the symptoms of Ménière's disease, sense of coherence (SOC), positive attitude, participation and restriction problems classified by the International Classification of Function (ICF), and general health related quality of life (EQ-5D). Results: Seventy percent of the subjects reported fatigue and in 30% fatigue was moderate or strong. Fatigue was associated with reduced quality of life and complaints of vertigo attacks, balance problems and hearing loss. Mobility related symptoms and mood disorders in a broad sense were the most significant determinants of fatigue. SOC and attitude were predictors of reduced vitality. Analysis based on participation restrictions indicated isolation being a consequence of fatigue. In the analysis the severity of the disease was controlled. Conclusion: Fatigue is a common complaint in Ménière's disease, reducing quality of life and leading to social and personal isolation. Fatigue is associated with personality trait and anxiety disorders. Therapeutically, a positive attitude and physical activity might help to reduce anxiety and escape the social and personal isolation. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate whether rehabilitation of muscle force or balance improves postural stability and quality of life (QoL), and whether self-administered training is comparable with guided training among older adults residing in an institutional setting. Patients and methods: A randomized, prospective intervention study was undertaken among 55 elderly patients. Three intervention groups were evaluated: a muscle force training group; a balance and muscle force training group; and a self-administered training group. Each group underwent 1-hour-long training sessions, twice a week, for 3 months. Postural stability was measured at onset, after 3 months, and after 6 months. Time-domain-dependent body sway variables were calculated. The fall rate was evaluated for 3 years. General health related quality of life (HRQoL) was measured with a 15D instrument. Postural stability was used as a primary outcome, with QoL and falls used as secondary outcomes. Results: Muscle force trainees were able to undertake training, progressing towards more strenuous exercises. In posturography, the number of spiky oscillations was reduced after training, and stationary fields of torque moments of the ankle increased, providing better postural stability in all groups; in particular, the zero crossing rate of weight signal and the number of low variability episodes in the stabilogram were improved after training. While no difference was found between different training groups in posturography outcomes, a reduction of fall rate was significant in only the guided training groups. A significant part of the variability of the QoL could be explained by the posturography outcome (46%). However, the outcome of training was associated with a reduced QoL. Conclusion: Even moderate or severely demented residents could do exercises in five-person groups under the supervision of a physiotherapist. An improvement in postural stability was observed in all training groups, indicating that even self-administered training could be beneficial. Posturography outcome indicated that training alters the postural strategy by reducing the oscillatory fluctuations of body sway signal. However, only guided training tended to reduce falls. Short training intervention programs may decrease QoL by changing the elderly's daily routine and making it more active and exhausting. [ABSTRACT FROM AUTHOR]

Objective: To determine the effects of their partners' MD on the significant others of the patients. Design: Open-ended questionnaire. Study sample: Significant others of members of the Finnish Ménière's Federation. Results: The predominant responses concerned effects on their lives and lifestyle-participation restrictions (effects on personal and community life)-and on personal contextual factors (uncertainty of life). In contrast they fail to list such effects of the patients, focussing rather on the patients' symptoms. Five percent of the responses given entailed positive experiences. Conclusions: Significant others of patients with MD listed a wide range of effects of their partner's condition on them. We encourage doctors and therapists to include the significant others in the rehabilitation process to enable them to understand the patient's condition, to help the significant other, and so better support the patients concerned. [ABSTRACT FROM AUTHOR]

Objective: To determine the effects of their partners' MD on the significant others of the patients. Design: Open-ended questionnaire. Study sample: Significant others of members of the Finnish Ménière's Federation. Results: The predominant responses concerned effects on their lives and lifestyle-participation restrictions (effects on personal and community life)-and on personal contextual factors (uncertainty of life). In contrast they fail to list such effects of the patients, focussing rather on the patients' symptoms. Five percent of the responses given entailed positive experiences. Conclusions: Significant others of patients with MD listed a wide range of effects of their partner's condition on them. We encourage doctors and therapists to include the significant others in the rehabilitation process to enable them to understand the patient's condition, to help the significant other, and so better support the patients concerned. [ABSTRACT FROM AUTHOR]

A force platform is widely used in the evaluation of postural stability in man. Although an abundance of parameters are typically retrieved from force platform data, no uniform analysis of the data has been carried out. In general, the signal analysis does not analyze the underlying postural event, i.e., whether the signal consists of several small corrections or large excursions. In the present work, we studied the postural stability of 4589 elderly persons from Iceland on a force platform under visual and non-visual conditions during stance on a solid surface. We analyzed the internal relationship between frequently used time domain variables. In addition, we conducted a factor analysis using a subset of selected variables. Factor analysis yielded three components that can be considered different strategies for maintaining posture. In one control strategy, long swaying amplitues were pronounced, allowing the person to react when postural confidence limits are reached. In a second strategy, a high oscillation rate about the stationary point was the dominant characteristic of maintaining postural control. The third strategy appears to involve a short critical time period during which an open loop control changes into a closed loop that very rapidly controls excessive postural oscillations. The findings suggest that conventional parameters such as swaying velocity and amplitude alone do not provide sufficient information regarding a person's ability to maintain an upright stance. [ABSTRACT FROM AUTHOR]

Background and aims: Dizziness, impaired balance and fear of falling are common complaints in the elderly. We evaluated the association of vestibular symptoms with vestibular findings in the elderly by posturography and video-oculography (VOG). Methods: We studied 38 oldest old subjects (≥85 yrs, mean age 89) living in a residential home. Vestibular symptoms were taken with a structured questionnaire, the Mini Mental State Examination (MMSE) was scored and any falls were recorded over a period of 12 months. Posturography was measured with a force platform and eye movements were measured by video-oculography. Results: In the majority of the elderly, vestibular abnormalities were found, such as reduced vestibulo-ocular reflex gain 6/38, spontaneous nystagmus 5/38, gaze deviation nystagmus 5/38, head shaking nystagmus 9/38, pathologic head thrust test 10/38, and positional nystagmus 17/38. Posturography demonstrated two major findings: the body support area was limited and the use of vision for postural control was reduced. In principal component analysis of the vertigo, four major factors described elements of failure in the vestibular and other systems important to maintenance of balance: episodic vertigo, postural instability, multisystem failure (frail) and presyncopal imbalance. These four factors were associated in different degrees to vestibular abnormalities and falls. During the follow-up period, in 19 elderly (19/38), one or more falls were recorded. Conclusions: Progressive loss of balance in the aged, or "presbyequilibrium," is a complex and incompletely understood process involving vestibular, oculomotor, visual acuity, proprioception, motor, organ system and metabolic weaknesses and disorders. These factors provide a potential basis for streamlining diagnostic evaluations and aiding in planning for effective therapy. In oldest old, these problems are magnified, increasing the need for additional expertise in their care, which may be met by training specialized healthcare staff. [ABSTRACT FROM AUTHOR]

The human postural control system is complex and it combines information from different sources. The most important information comes from vestibular, visual and proprioceptive senses. We studied the effects of removing the visual and proprioceptive information simultaneously. The force feedback from the ground was removed with vibrators attached on the musculus soleus of both calves. By using features of force platform signals, when the vibrators were on, the lengths of the swaying paths were four times the lengths when the vibrators were off. Our results show that it is possible to separate the effects of the visual and proprioceptive senses from that of vestibular sense, which is very useful for investigations of balance problems in otoneurology. This supports our future aim to classify between healthy subjects and different otoneurological patients with signal analysis and pattern recognition methods to be used for force platform signals. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which is concerned with research which investigated an intervention to prevent falls in elderly adults living in a residential home.