The authors thank Dr. Honghua Zhou for digital technology support.&#160;This study was supported by Capital&#39;s Funds for Health Improvement and Research of China&#160;(ID:2024-2-7031).

This study was approved by the Academic Ethics Committee of the Seventh Medical Center of Chinese PLA General Hospital in Beijing, China.
1. Participant inclusion/exclusion criteria
<ol>
	<li>Recruit aged participants 65 years or older and obtain their informed consent.</li>
	<li>Exclude participants who have obvious visual and lower limb disability, such as knee arthritis, thromboangiitis obliterans, and gout.</li>
</ol>
2. Preparation of the test area
<ol>
	<li>Set up the standardized iTUG test area of 5 m x 8 m or wider (see Figure 1) with 12 cameras distributed around the room. Put the traditional TUG setups into the test area: a chair and a sign to remind the participant to turn back. 
	NOTE: Signs indicating route lines are optional.</li>
	<li>Ensure that the motion capture area is limited to the scope of all the cameras and all the TUG test setup is non-light reflective.</li>
</ol>
3. Software preparation for the procedures before the test
<ol>
	<li>Install the motion capture software on the computer to be used in the room.</li>
	<li>Click the Seeker button to start the motion capture software. After starting the software, for General Camara Configuration, choose the default mode (frame rate = 60 frames/s, shutter speed = 1/1,000 s), which is acceptable for most situations. Set Selected Camera Settings and Camera Configuration Settings also in the default mode.</li>
	<li>Select Live mode to set the real-time settings. 
	NOTE: Post mode is used to analyze the data captured.</li>
	<li>Click on Markersets to configure the marker settings.</li>
	<li>Select XY axis in the Calibration of Ground Axis and millimeters in Calibration units.</li>
	<li>Click on Calibrate to select the calibration variation.</li>
	<li>Select Initial Calibration and click on the &#34;L&#34; shaped button. At the same time, take the &#34;L&#34; shaped calibrator into the field and put it in the center of the field to make sure it can be captured by all the cameras. 
	NOTE: The &#34;L&#34; shaped calibrator contains four light-reflective markers.</li>
	<li>Check on the screen whether all the 12 cameras can detect four reflective markers. If any camera detects &#8804;3 markers, reduce lightness and threshold at the left of the screen. If any camera detects &#8805;5 markers, check the field and clean or cover the unwanted reflective markers. 
	NOTE: Some tiny belongings of the former participant might be detected by the camera.</li>
	<li>Remove the &#34;L&#34; shaped calibrator from the field.</li>
	<li>Click on the &#34;T&#34; shaped button. At the same time, take the &#34;T&#34; shaped calibrator into the field and wave it to make sure it can be captured by all the cameras.</li>
	<li>Select Z axis in the Calibration of Up Axis and millimeters in Calibration units.</li>
	<li>Have the doctors check whether all the cameras can capture the markers. Wave the markers in each corner of the field, especially covering the possible space of the TUG test.</li>
	<li>Check in the screen whether all 12 cameras can detect the &#34;T&#34; shaped calibrator. If any camera cannot detect it, change the direction of the camera. 
	NOTE: There are two shapes of markers that need to be calibrated; &#34;L&#34; shaped and &#34;T&#34; shaped. The &#34;L&#34; shaped calibrator has four light-reflective points to calibrate the XY axis, and the &#34;T&#34; shaped calibrator has four light-reflective points to calibrate the Z axis. The calibration duration will last 60 s or more. An effective capture will turn the color of the screen green.</li>
	<li>Click Finish to complete the calibration.</li>
	<li>Click Save Calibration to store the effective calibration mode. 
	NOTE: The calibration is performed in a 2D model; a 3D model is often used during the test.</li>
</ol>
4. iTUG test
NOTE: The participants should wear tight but comfortable clothes and shoes.
<ol>
	<li>Attach the reflective points on the anatomical landmarks: cervical 7 spinous process andthoracic 10 spinous process, left acromion and right acromion. 
	NOTE: Each participant could have up to 17 reflective points attached. The more reflective points that are attached, the more accurate the data collected, but also the less comfortable the participants feel.</li>
	<li>Right-click the reflective points at the right line of the screen and nominate them as C7, T10, left shoulder, and right shoulder.</li>
	<li>Show the instruction to the participants. The instruction is &#34;Please rise from the chair, walk 3 m at your preferred speed, turn around, return, and sit.&#34;</li>
	<li>Ask the participants to perform the iTUG test beforehand to make sure they are familiar with the instruction. 
	NOTE: Make sure each participant is comfortable after the reflective points are attached.</li>
	<li>Instruct the participant to perform the iTUG test. 
	NOTE: The participants need to walk to complete the iTUG task.</li>
	<li>While the participant is performing the iTUG test, click the start and stop buttons on the screen of the computer. 
	NOTE: During the iTUG test, the motion capture system samples data from all attached points at a frequency of 60 Hz; a video is formed accordingly (see Video 1).</li>
</ol>
5. Data collection and definition of iTUG test variables
<ol>
	<li>Click the Recording Setting button. 
	NOTE: The data are stored and found in a spreadsheet.</li>
	<li>Select Raw Camera Data |Tracked ASCTI | Tracked Binary. The Capture Duration is 20 s.</li>
	<li>Type in the name of the participant.</li>
	<li>Click the Record button to start data collection.</li>
	<li>Identify sub-phases of the iTUG test by reviewing the video and calculate the variables according to the data.
	<ol>
		<li>Define the following variables: traditional TUG test total time, phase 1 time (rising from the chair), phase 1 body sway (rising from the chair), phase 2 time (walking 3 m at the preferred speed), phase 2 body sway (walking 3 m at the preferred speed), phase 3 time (turning around), phase 3 body sway (turning around), angular velocity of phase 3 (turning around), phase 4 time (returning), phase 4 body sway (returning), and phase 5 time (sitting). 
		NOTE: The details are similar to those described by Caronni and colleagues15.</li>
	</ol>
	</li>
</ol>
6. Downton Fall Risk Index (DFRI)
<ol>
	<li>Assess the falling risk using the Downton Fall Risk Index (DFRI). 
	NOTE: The DFRI (Table 1) includes 11 risk items, which are scored one point each. Scores are summed to a total index score, range 0-11. A score of &#8805;3 is considered to indicate a high risk of falls. To evaluate falling risk, DFRI is usually used for participants admitted in a hospital, and the Home Falls and Accidents Screening Tool (HOME FAST) is more suitable for community dwellers.</li>
</ol>
7. Statistical analysis
<ol>
	<li>Use a commercially available statistical software package to perform all statistical analyses. Use Student&#39;s t-test to assess group differences and choose Pearson correlation coefficient to assess the relationship between subcomponents of iTUG and DFRI score on the total sample, with P &#60; 0.05 indicating a statistically significant difference.</li>
	<li>Use the Bland-Altman procedures to assess agreement for Phase 1 duration, Phase 3 angular velocity, and Phase 4 duration between our method and the McRoberts sensor (see the Table of Materials). Calculate the mean difference between the two methods of measurement and the 95% limit of agreement for the mean difference calculated.</li>
</ol>

Evaluating the Risk of Falling in Elderly Using iTUG Motion Capture Technology

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M., Korevaar, J. C., Leemrijse, C. J., Van de Goor, I. 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A study on obese women.</a> J Electromyogr Kinesiol. 44, 78-85 (2019).</li><li>Ayena, J. C., Chioukh, L., Otis, M. J., Deslandes, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Risk+of+falling+in+a+timed+up+and+go+test+using+an+UWB+Radar+and+an+instrumented+insole.">Risk of falling in a timed up and go test using an UWB Radar and an instrumented insole.</a> Sensors. 21 (3), 722 (2021).</li><li>Sample, R. B., Kinney, A. L., Jackson, K., Diestelkamp, W., Bigelow, K. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+key+outcome+measures+when+using+the+instrumented+timed+up+and+go+and/or+posturography+for+fall+screening.">Identification of key outcome measures when using the instrumented timed up and go and/or posturography for fall screening.</a> Gait Posture. 57, 168-171 (2017).</li><li>Beyea, J., McGibbon, C. A., Sexton, A., Noble, J., O'Connell, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Convergent+validity+of+a+wearable+sensor+system+for+measuring+sub-task+performance+during+the+timed+up-and-go+test.">Convergent validity of a wearable sensor system for measuring sub-task performance during the timed up-and-go test.</a> Sensors. 17 (4), 934 (2017).</li><li>McGough, E. L., Gries, M., Teri, L., Kelly, V. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Validity+of+instrumented+360&#176;+turn+test+in+older+adults+with+cognitive+impairment.">Validity of instrumented 360&#176; turn test in older adults with cognitive impairment.</a> Phys Occup Ther Geriatr. 38 (2), 170-184 (2020).</li><li>Wang, H., Brown, S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+effects+of+total+ankle+replacement+on+ankle+joint+mechanics+during+walking.">The effects of total ankle replacement on ankle joint mechanics during walking.</a> J Sport Health Sci. 6 (3), 340-345 (2017).</li><li>Mehdizadeh, S., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Toronto+older+adults+gait+archive:+video+and+3D+inertial+motion+capture+data+of+older+adults'+walking.">The Toronto older adults gait archive: video and 3D inertial motion capture data of older adults' walking.</a> Sci Data. 9 (1), 398 (2022).</li><li>Caronni, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Criterion+validity+of+the+instrumented+Timed+Up+and+Go+test:+A+partial+least+square+regression+study.">Criterion validity of the instrumented Timed Up and Go test: A partial least square regression study.</a> Gait Posture. 61, 287-293 (2018).</li><li>Mojtaba, M., Alinaghizadeh, H., Rydwik, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Downton+Fall+Risk+Index+during+hospitalisation+is+associated+with+fall-related+injuries+after+discharge:+a+longitudinal+observational+study.">Downton Fall Risk Index during hospitalisation is associated with fall-related injuries after discharge: a longitudinal observational study.</a> J Physiother. 64 (3), 172-177 (2018).</li><li>Hershkovitz, L., Malcay, O., Grinberg, Y., Berkowitz, S., Kalron, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+contribution+of+the+instrumented+Timed-Up-and-Go+test+to+detect+falls+and+fear+of+falling+in+people+with+multiple+sclerosis.">The contribution of the instrumented Timed-Up-and-Go test to detect falls and fear of falling in people with multiple sclerosis.</a> Mult Scler Relat Disord. 27, 226-231 (2019).</li><li>Zarzeczny, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Aging+effect+on+the+instrumented+Timed-Up-and-Go+test+variables+in+nursing+home+women+aged+80-93+years.">Aging effect on the instrumented Timed-Up-and-Go test variables in nursing home women aged 80-93 years.</a> Biogerontology. 18 (4), 651-663 (2017).</li><li>Kim, K. 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The authors have no conflicts of interest to disclose.

The critical steps in the protocol are to attach the reflective points accurately to the anatomical landmarks to avoid bias. Furthermore, the identification of each subcomponent of the iTUG test is also a critical step; a video review is helpful for the identification.
A marginal difference existed between groups in the TUG test scores implying that traditional TUG scores might not be sensitive enough to discriminate risk of falling. We did not find obvious differences between the groups in Ph...

Falling is one of the most common geriatric syndromes and is the second leading cause of accidental or unintentional injury-related deaths worldwide1. In adults aged above 65 years, falling can result in functional impairment, disability, decreased quality of life, increased length of stay in hospitals, and even mortality2,3. Therefore, preventing falls is of utmost importance.
To determine predictors of fall events, previous researchers have focused on gait analyses, balance tests, mental state, sedative drug use, as well as history of falling in the preceding year4,5 The Timed Up and Go (TUG) test is a quick performance-based measure of mobility. The TUG test has been extensively studied in older adults and is recommended as a simple screening test for the risk of falls6. This widely used test consists of rising from a chair, walking 3 m at the preferred speed, turning around, returning, and sitting. The traditional clinical outcome of this test depends on its total duration7 and is assessed by a stopwatch.
In clinical practice, the conventional TUG test measures the total time to perform a series of activities without dividing the performance of the subject into subcomponents8. Recently, some investigators have proposed that different TUG test components might be particularly sensitive as predictors of future falls9. When using the digitized instrumented TUG (iTUG) test, the individual components of the TUG test can be analyzed separately. By using the iTUG, it is possible to objectively evaluate several characteristics of each TUG test sub-phase and obtain quantitative data, such as the relevant durations, velocities, and angular velocity of each movement. With more detailed data, the iTUG test has shown the advantage of detecting specific deficits that may be more indicative of the fall risk10.
As the gold standard in movement analysis, motion capture technologies have been used to detect movement in patients with Parkinson&#39;s Disease (PD)11, cognitive impairment12, and ankle arthritis13, as well as in healthy adults14. In the current study, we aimed to analyze the iTUG test subcomponents using motion capture technology and to determine the correlation between iTUG test subtasks and the potential risk of future falls.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>Black strip</td>
			<td>Deli</td>
			<td>60 mm x 20 m</td>
			<td></td>
		</tr>
		<tr>
			<td>Calibrator</td>
			<td>NOKOV</td>
			<td>reflector marker1</td>
			<td>L shape</td>
		</tr>
		<tr>
			<td>Calibrator</td>
			<td>NOKOV</td>
			<td>reflector marker2</td>
			<td>T shape</td>
		</tr>
		<tr>
			<td>Chair</td>
			<td>YUANSHENGYUANDAI</td>
			<td>&#8220;10076062317820&#8221;</td>
			<td></td>
		</tr>
		<tr>
			<td>Computer</td>
			<td>HUAWEI</td>
			<td>HONOR</td>
			<td></td>
		</tr>
		<tr>
			<td>McRoberts sensor&#160;</td>
			<td colspan="3">DynaPort Hybrid, McRoberts, The Hague, The Netherland</td>
		</tr>
		<tr>
			<td>Motion capture camera</td>
			<td>NOKOV</td>
			<td>Mars2H</td>
			<td></td>
		</tr>
		<tr>
			<td>Motion capture software</td>
			<td>NOKOV</td>
			<td>DG-01</td>
			<td></td>
		</tr>
		<tr>
			<td>Reflective marker</td>
			<td>NOKOV</td>
			<td>small marker</td>
			<td>for calibrators</td>
		</tr>
		<tr>
			<td>Reflective marker</td>
			<td>NOKOV</td>
			<td>large marker</td>
			<td>for participants</td>
		</tr>
	</tbody>
</table>

using motion capture technology in the instrumented timed up and go test to detect the risk of falling in aged adults

Despite efforts made by medicine and technology, the incidence of falls in older adults is still increasing. Therefore, early detection of the falling risk is becoming increasingly important for falling prevention. The Timed Up and Go (TUG) test is a well-accepted tool to assess mobility and can be used in predicting future fall risk in aged adults. In clinical practice, the total time to complete the test is the main outcome measure of the TUG test. Owing to its simplicity and generality, the traditional TUG test has been considered a global test for movement analysis. However, recently, researchers have attempted to split the TUG test into subcomponents and have updated its score system for further investigations. The instrumented Time Up and Go (iTUG) test, which is a new modification of the traditional TUG test, has been reported to be a sensitive tool for predicting movement disorders and the risk of falls in older adults. The goal of the present study was to analyze the iTUG test subcomponents using motion capture technology, and to determine which iTUG test subtasks are related to the potential risk of future falls.

Thirteen aged participants with a high risk of falling (DFRI score: 3-11) and 11 aged subjects with a low risk of falling (DFRI score: 0-2) were recruited. The DFRI is detailed in Table 1. As has been mentioned previously, a score of 3 or more is considered to indicate a high risk of falls for patients during hospitalization16.
Demographic data are shown in Table 1, which...

Author Spotlight: Innovations in iTUG Test for Enhanced Risk Assessment and Cognitive Insights

The instrumented Timed Up and Go (iTUG) test is gaining increasing attention in body sway and gait analysis with the development of new technologies. We present a protocol to analyze the subcomponents of the iTUG with motion capture.

Using Motion Capture Technology in the Instrumented Timed Up and Go Test to Detect the Risk of Falling in Aged Adults

Despite efforts made by medicine and technology, the incidence of falls in older adults is still increasing. Therefore, early detection of the falling ...

using-motion-capture-technology-instrumented-timed-up-go-test-to

Research

JoVE Journal

Medicine

739 Views.  The Seventh Medical Center of Chinese PLA General Hospital. The instrumented Timed Up and Go (iTUG) test is gaining increasing attention in body sway and gait analysis with the development of new technologies. We present a protocol to analyze the subcomponents of the iTUG with motion capture.

Video: Author Spotlight: Innovations in iTUG Test for Enhanced Risk Assessment and Cognitive Insights

Making Sense of Listening: The IMAP Test Battery

The ability to hear is only the first step towards making sense of the range of information contained in an auditory signal. Of equal importance are the abilities to extract and use the information encoded in the auditory signal. We refer to these as listening skills (or auditory processing AP). Deficits in these skills are associated with delayed language and literacy development, though the nature of the relevant deficits and their causal connection with these delays is hotly debated.
When a child is referred to a health professional with normal hearing and unexplained difficulties in listening, or associated delays in language or literacy development, they should ideally be assessed with a combination of psychoacoustic (AP) tests, suitable for children and for use in a clinic, together with cognitive tests to measure attention, working memory, IQ, and language skills. Such a detailed examination needs to be relatively short and within the technical capability of any suitably qualified professional. Current tests for the presence of AP deficits tend to be poorly constructed and inadequately validated within the normal population. They have little or no reference to the presenting symptoms of the child, and typically include a linguistic component. Poor performance may thus reflect problems with language rather than with AP. To assist in the assessment of children with listening difficulties, pediatric audiologists need a single, standardized child-appropriate test battery based on the use of language-free stimuli.
We present the IMAP test battery which was developed at the MRC Institute of Hearing Research to supplement tests currently used to investigate cases of suspected AP deficits. IMAP assesses a range of relevant auditory and cognitive skills and takes about one hour to complete. It has been standardized in 1500 normally-hearing children from across the UK, aged 6-11 years. Since its development, it has been successfully used in a number of large scale studies both in the UK and the USA. IMAP provides measures for separating out sensory from cognitive contributions to hearing. It further limits confounds due to procedural effects by presenting tests in a child-friendly game-format. Stimulus-generation, management of test protocols and control of test presentation is mediated by the IHR-STAR software platform. This provides a standardized methodology for a range of applications and ensures replicable procedures across testers. IHR-STAR provides a flexible, user-programmable environment that currently has additional applications for hearing screening, mapping cochlear implant electrodes, and academic research or teaching.

A test battery (IMAP) for performing an in-depth assessment of auditory and cognitive abilities contributing to listening skills is described. It is quick to administer, child-friendly and free from linguistic confounds. Stimulus generation and protocol management are controlled via a software platform (IHR-STAR) to ensure replicable procedures.

The ability to hear is only the first step towards making sense of the range of information contained in an auditory signal. Of equal importance are the ...

A Strategy to Identify de Novo Mutations in Common Disorders such as Autism and Schizophrenia

There are several lines of evidence supporting the role of de novo mutations as a mechanism for common disorders, such as autism and schizophrenia. First, the de novo mutation rate in humans is relatively high, so new mutations are generated at a high frequency in the population. However, de novo mutations have not been reported in most common diseases. Mutations in genes leading to severe diseases where there is a strong negative selection against the phenotype, such as lethality in embryonic stages or reduced reproductive fitness, will not be transmitted to multiple family members, and therefore will not be detected by linkage gene mapping or association studies. The observation of very high concordance in monozygotic twins and very low concordance in dizygotic twins also strongly supports the hypothesis that a significant fraction of cases may result from new mutations. Such is the case for diseases such as autism and schizophrenia. Second, despite reduced reproductive fitness1 and extremely variable environmental factors, the incidence of some diseases is maintained worldwide at a relatively high and constant rate. This is the case for autism and schizophrenia, with an incidence of approximately 1% worldwide. Mutational load can be thought of as a balance between selection for or against a deleterious mutation and its production by de novo mutation. Lower rates of reproduction constitute a negative selection factor that should reduce the number of mutant alleles in the population, ultimately leading to decreased disease prevalence. These selective pressures tend to be of different intensity in different environments. Nonetheless, these severe mental disorders have been maintained at a constant relatively high prevalence in the worldwide population across a wide range of cultures and countries despite a strong negative selection against them2. This is not what one would predict in diseases with reduced reproductive fitness, unless there was a high new mutation rate. Finally, the effects of paternal age: there is a significantly increased risk of the disease with increasing paternal age, which could result from the age related increase in paternal de novo mutations. This is the case for autism and schizophrenia3. The male-to-female ratio of mutation rate is estimated at about 4&#x2013;6:1, presumably due to a higher number of germ-cell divisions with age in males. Therefore, one would predict that de novo mutations would more frequently come from males, particularly older males4. A high rate of new mutations may in part explain why genetic studies have so far failed to identify many genes predisposing to complexes diseases genes, such as autism and schizophrenia, and why diseases have been identified for a mere 3% of genes in the human genome. Identification for de novo mutations as a cause of a disease requires a targeted molecular approach, which includes studying parents and affected subjects. The process for determining if the genetic basis of a disease may result in part from de novo mutations and the molecular approach to establish this link will be illustrated, using autism and schizophrenia as examples.

Molecular genetic strategy for finding de novo mutations causing common disorders such as autism and schizophrenia.

There are several lines of evidence supporting the role of de novo mutations as a mechanism for common disorders, such as autism and schizophrenia. First, ...

The Measurement and Treatment of Suppression in Amblyopia

Amblyopia, a developmental disorder of the visual cortex, is one of the leading causes of visual dysfunction in the working age population. Current estimates put the prevalence of amblyopia at approximately 1-3%1-3, the majority of cases being monocular2. Amblyopia is most frequently caused by ocular misalignment (strabismus), blur induced by unequal refractive error (anisometropia), and in some cases by form deprivation.
Although amblyopia is initially caused by abnormal visual input in infancy, once established, the visual deficit often remains when normal visual input has been restored using surgery and/or refractive correction. This is because amblyopia is the result of abnormal visual cortex development rather than a problem with the amblyopic eye itself4,5 . Amblyopia is characterized by both monocular and binocular deficits6,7 which include impaired visual acuity and poor or absent stereopsis respectively. The visual dysfunction in amblyopia is often associated with a strong suppression of the inputs from the amblyopic eye under binocular viewing conditions8. Recent work has indicated that suppression may play a central role in both the monocular and binocular deficits associated with amblyopia9,10 .
Current clinical tests for suppression tend to verify the presence or absence of suppression rather than giving a quantitative measurement of the degree of suppression. Here we describe a technique for measuring amblyopic suppression with a compact, portable device11,12 . The device consists of a laptop computer connected to a pair of virtual reality goggles. The novelty of the technique lies in the way we present visual stimuli to measure suppression. Stimuli are shown to the amblyopic eye at high contrast while the contrast of the stimuli shown to the non-amblyopic eye are varied. Patients perform a simple signal/noise task that allows for a precise measurement of the strength of excitatory binocular interactions. The contrast offset at which neither eye has a performance advantage is a measure of the "balance point" and is a direct measure of suppression. This technique has been validated psychophysically both in control13,14 and patient6,9,11 populations.
In addition to measuring suppression this technique also forms the basis of a novel form of treatment to decrease suppression over time and improve binocular and often monocular function in adult patients with amblyopia12,15,16 . This new treatment approach can be deployed either on the goggle system described above or on a specially modified iPod touch device15.

Amblyopia is a developmental disorder of the visual cortex that is often accompanied by strong suppression of one eye. We present a new technique for measuring and treating interocular suppression in patients with amblyopia that can be deployed using virtual reality goggles or a portable iPod Touch device.

Amblyopia, a developmental disorder of the visual cortex, is one of the leading causes of visual dysfunction in the working age population. Current ...

Technical Aspects of the Mouse Aortocaval Fistula

Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta and inferior vena cava (IVC) are exposed. The proximal infrarenal aorta and the distal aorta are dissected for clamp placement and needle puncture, respectively. Special attention is paid to avoid dissection between the aorta and the IVC. After clamping the aorta, a 25 G needle is used to puncture both walls of the aorta into the IVC. The surrounding connective tissue is used for hemostatic compression. Successful creation of the AVF will show pulsatile arterial blood flow in the IVC. Further confirmation of successful AVF can be achieved by post-operative Doppler ultrasound.

The goal is to produce an arteriovenous fistula that is simple and reproducible. This method does not use sutures or glue adhesive. Therefore the samples can be used with the least amount of foreign materials for analysis.

Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta ...

High-throughput Flow Cytometry Cell-based Assay to Detect Antibodies to N-Methyl-D-aspartate Receptor or Dopamine-2 Receptor in Human Serum

Over the recent years, antibodies against surface and conformational proteins involved in neurotransmission have been detected in autoimmune CNS diseases in children and adults. These antibodies have been used to guide diagnosis and treatment. Cell-based assays have improved the detection of antibodies in patient serum. They are based on the surface expression of brain antigens on eukaryotic cells, which are then incubated with diluted patient sera followed by fluorochrome-conjugated secondary antibodies. After washing, secondary antibody binding is then analyzed by flow cytometry. Our group has developed a high-throughput flow cytometry live cell-based assay to reliably detect antibodies against specific neurotransmitter receptors. This flow cytometry method is straight forward, quantitative, efficient, and the use of a high-throughput sampler system allows for large patient cohorts to be easily assayed in a short space of time. Additionally, this cell-based assay can be easily adapted to detect antibodies to many different antigenic targets, both from the central nervous system and periphery. Discovering additional novel antibody biomarkers will enable prompt and accurate diagnosis and improve treatment of immune-mediated disorders.

Over the recent years, live cell-based assays have been used successfully to detect antibodies against surface and conformational antigens. Here, we describe a method using high-throughput flow cytometry enabling the analysis of large cohorts of patients. Detection of novel antibodies will improve diagnosis and treatment of immune-mediated disorders.

Over the recent years, antibodies against surface and conformational proteins involved in neurotransmission have been detected in autoimmune CNS diseases ...

Collection and Extraction of Saliva DNA for Next Generation Sequencing

The preferred source of DNA in human genetics research is blood, or cell lines derived from blood, as these sources yield large quantities of high quality DNA. However, DNA extraction from saliva can yield high quality DNA with little to no degradation/fragmentation that is suitable for a variety of DNA assays without the expense of a phlebotomist and can even be acquired through the mail. However, at present, no saliva DNA collection/extraction protocols for next generation sequencing have been presented in the literature. This protocol optimizes parameters of saliva collection/storage and DNA extraction to be of sufficient quality and quantity for DNA assays with the highest standards, including microarray genotyping and next generation sequencing.

DNA extraction from saliva can provide a readily available source of high molecular weight DNA, with little to no degradation/fragmentation. This protocol provides optimized parameters for saliva collection/storage and DNA extraction to be of sufficient quality and quantity for downstream DNA assays with high quality requirements.

The preferred source of DNA in human genetics research is blood, or cell lines derived from blood, as these sources yield large quantities of high quality ...

Topical Airway Anesthesia for Awake-endoscopic Intubation Using the Spray-as-you-go Technique with High Oxygen Flow

A patient&#39;s willingness to cooperate is an absolute precondition for successful awake intubation of the trachea. Whilst drug-sedation of patients can jeopardize their spontaneous breathing, topical anesthesia of the airway is a popular technique. The spray-as-you-go technique represents one of the simplest opportunities to anesthetize the airway mucosa. The application of local anesthetic through the working channel of the flexible endoscope is a widespread practice for anesthetists as well as pulmonologists. There is neither need for additional devices nor special training as a pre-requisite to perform this technique. However, a known clinical problem is the coughing and gagging reflex that may occur when the liquid anesthetic strikes the airway mucosa and other sensitive structures like the vocal cords. This can be avoided by the use of oxygen applied through the working channel with the aim of fogging the local anesthetic into finer particles. Furthermore, the oxygen flow provides a higher oxygen supply and contributes to a better view, dispersing mucus secretions and blood away from the lens. Using an atomizer with a high oxygen flow of 10 L/min we maximized these benefits, caused less coughing and had more satisfied and therefore cooperative patients. Possible, but very rare complications of using oxygen flow including gastric insufflation, organ rupture or barotrauma did not arise. We attribute the complication-free use of high oxygen flow to the design of the set, which permits flow and pressure release.

The topical anesthetic lidocaine was atomized using a high oxygen flow through the working channel of a flexible intubating endoscope to achieve topical airway anesthesia for awake endotracheal intubation. We prefer this modified spray-as-you-go technique for endoscopic intubation to classical bolus application because of higher patient satisfaction and better compliance.

A patient&#39;s willingness to cooperate is an absolute precondition for successful awake intubation of the trachea. Whilst drug-sedation of patients can ...

Oral Health Assessment by Lay Personnel for Older Adults

Oral health is an often-undervalued contributor to overall health. The literature, however, underscores the myriad of systemic diseases influenced by oral health, including type II diabetes, heart disease, and atherosclerosis. Thus, assessments of oral health, called oral screenings, have a significant role in assessing risk of disease, managing disease, and even improving disease by oral care. Here we present a method to assess oral health quickly and consistently across time. The protocol is simple enough for non-oral health professionals such as students, family, and caregivers. Useful for any age of patient, the method is particularly key for older individuals who are often at risk of inflammation and chronic disease. Components of the method include existing oral health assessment scales and inventories, which are combined to produce a comprehensive assessment of oral health. Thus, oral characteristics assessed include intraoral and extraoral structures, soft and hard tissues, natural and artificial teeth, plaque, oral functions such as swallowing, and the impact this oral health status has on the patient&#39;s quality of life. Advantages of this method include its inclusion of measures and perceptions of both the observer and patient, and its ability to track changes in oral health over time. Results acquired are quantitative totals of questionnaire and oral screening items, which can be summed for an oral health status score. The scores of successive oral screenings can be used to track the progression of oral health across time and guide recommendations for both oral and overall health care.

The goal of this protocol is to enable non-dental professionals to assess oral health status for research or health-screening purposes. Aspects assessed include lips, tongue, soft and hard tissues, natural and artificial teeth, oral cleanliness, plaque, swallowing, and impact of oral health on quality of life.

Oral health is an often-undervalued contributor to overall health. The literature, however, underscores the myriad of systemic diseases influenced by oral ...

Psychophysical Tracking Method to Assess Taste Detection Thresholds in Children, Adolescents, and Adults: The Taste Detection Threshold (TDT) Test

This paper describes a two-alternative, forced-choice, staircase, tracking procedure, called the Taste Detection Threshold (TDT) test, that provides a reliable measure of sweet, salty, and umami taste detection thresholds from childhood to adulthood. Advantages of the method include procedures that are identical for children and adults, thus allowing the determination of age-related and individual differences in taste perception, if any, and tasks that can be completed in a relatively short time frame, do not rely on continuous attention or require memorization, control for subjective response biases, and minimize the impact of language development. After a 1 hour fast, participants are presented with pairs of solutions; in each pair, one solution is water, and the other solution contains varying concentrations of the tastant.
Using a whole-mouth tasting method, participants taste each solution (without swallowing and with rinsing between tastings) and then point to the solution with a taste or that tastes different from water. The concentration of the stimulus in the subsequent pair increases after a single incorrect response and decreases after two consecutive correct responses. A reversal occurs when the concentration sequence changes direction. The task is deemed completed after the occurrence of four reversals, provided there are a maximum of two dilution steps between two successive reversals, and the series of reversals do not form an ascending pattern. These additional criteria ensure greater reliability in outcomes. The TDT is then calculated as the geometric mean of the concentrations of the four reversals. This method has real-world relevance as it provides information on a dimension of taste perception that is independent of hedonics, and that can change with aging and certain disease states, making it a valuable psychophysical test.

Psychophysical Tracking Method to Assess Taste Detection Thresholds in Children, Adolescents, and Adults: The Taste Detection Threshold TDT Test

Psychophysical tools measure the functionality of the taste system for both research and health assessment purposes. This paper describes a method to measure taste detection thresholds that can determine the lowest concentration of sucrose, sodium chloride, or monosodium glutamate that can be tasted by individuals as young as 6 years.

This paper describes a two-alternative, forced-choice, staircase, tracking procedure, called the Taste Detection Threshold (TDT) test, that provides a ...

Employing the Forced Oscillation Technique for the Assessment of Respiratory Mechanics in Adults

There is increasing interest in the use of the forced oscillation technique (FOT) or oscillometry to characterize respiratory mechanics in healthy and diseased individuals. FOT, a complementary method to traditional pulmonary function testing, utilizes a range of oscillatory frequencies superimposed on tidal breathing to measure the functional relationship between airway pressure and flow. This passive assessment provides an estimate of respiratory system resistance (Rrs) and reactance (Xrs) that reflect airway caliber and energy storage and dissipation, respectively. Despite the recent increase in popularity and updated Technical Standards, clinical adoption has been slow which relates, in part, to the lack of standardization regarding the acquisition and reporting of FOT data. The goal of this article is to address the lack of standardization across laboratories by providing a comprehensive written protocol for FOT and an accompanying video. To illustrate that this protocol can be utilized irrespective of a particular device, three separate FOT devices have been employed in the case examples and video demonstration. This effort is intended to standardize the use and interpretation of FOT, provide practical suggestions, as well as highlight future questions that need to be addressed.

As the use of forced oscillation technique (FOT) is increasingly utilized to characterize respiratory mechanics, there is a need to standardize methods with respect to nascent technical guidelines and various manufacturer's recommendations. A detailed protocol is provided including FOT assessment and interpretation for two cases to facilitate the standardization of methods.

There is increasing interest in the use of the forced oscillation technique (FOT) or oscillometry to characterize respiratory mechanics in healthy and ...