We would like to thank Dr. Johnathan Williams for his advice on MATLAB data processing.

The method reported was followed in a study that received ethical approval from the Bournemouth University Research Ethics Committee (Reference 15005).
1. Participants
<ol>
	<li>Recruit healthy adults (aged from 23 to 63 years, mean &#177; S.D.; 42.0 &#177; 13.4, body mass 70.4 &#177; 15.3 kg, height 175.5 &#177; 9.8 cm; 15 males, 15 females) to participate in the study. Thirty participants were recruited for this study.</li>
	<li>Ensure that there is no self-reported history of dizziness, balance problems or walking difficulties in the participants.</li>
	<li>Ensure that participants did not suffer from any known neuromuscular injury or condition affecting balance or walking.</li>
</ol>
2. Setup and procedures for gait analysis
<ol>
	<li>Use a gait analysis system (Figure 1) comprised of a dual-belt force plate-instrumented treadmill, a 10-camera motion capture system and a virtual environment that provides optic flow.</li>
	<li>Ensure that the participant is wearing very tight non-reflective clothing such as cycling shorts or leggings.</li>
	<li>Using double sided adhesive tapes attach 25 passive reflective markers and place according to the lower body configuration of the Human Body Model (HBM)7 as detailed in Table 1 and Figure 2. The information in this document is taken from the HBM Reference Manual8.</li>
	<li>Use a joint ruler to take measurements of the required knee and ankle widths for the HBM6.</li>
	<li>Secure participant to a safety harness that is fastened to an overhead frame.</li>
	<li>Start a new session in the database and make sure it is active (highlighted).</li>
	<li>Using the subject tab, create a new participant from the Labeling Skeleton button.</li>
	<li>Browse to the &#39;LowerLimb HBM_N2.vst&#39; file and then enter the name of the participant. The new participant appears in the Subjects pane.</li>
	<li>Go to the Tools pane and open the Subject Preparation tab.</li>
	<li>Zero level the forceplates via the Hardware tab. Make sure that no weight is exerted on the force plates.</li>
	<li>Prepare the participant for the ROM trial by having them ready in the middle of the treadmill.</li>
	<li>To ensure the participant can accustom themselves to the self-paced treadmill, ask them to walk at a comfortable speed for 5 min at the beginning of the session9,10.</li>
	<li>Following the acclimatization and without any delay time, ask the participant to walk for a minimum of 5 min10,11.</li>
	<li>Ensure participants are blinded to the timing of the recordings.</li>
	<li>Ensure to start the treadmill and start data recordings by clicking the Start recording button12. This can be done with integrated software (Table of Materials).</li>
	<li>Stop the recording after acquiring the desired amount of data. It is recommended to collect three sets of 25 cycles.</li>
	<li>Open the processing software (Table of Materials) and remove the high-frequency noise on data, by selecting a low-pass filter to the marker data such as a second order Butterworth filter with a cut-off frequency of 6 Hz.</li>
	<li>Go to File, and then select Export to save as a .csv.</li>
	<li>Determine individual strides from vertical force data and use the foot markers to ascertain gait events13.</li>
	<li>Analyze the gait parameters such as kinematic, kinetic and spatial-temporal data in Matlab R2017a (Supplementary File).</li>
</ol>
3. Setup and procedures for muscle strength test
<ol>
	<li>Use the muscle strength testing equipment (multimodal dynamometer) (Figure 3), to measure participants&#39; muscle strength based on Maximum Voluntary Isometric Contraction (MVIC)14.</li>
	<li>Attach the tool/pad number 701 to the dynamometer exercise head.</li>
	<li>Test participant&#39;s right and left knee isometric muscle strength.</li>
	<li>Test participants in a seated position on a chair with a backrest.</li>
	<li>Using the up/down switch, align the dynamometer axis with the knee joint&#39;s anatomical axis of rotation. Place the pad of the tool centrally at the lower part of the shin of the tibia.</li>
	<li>Keep the knee at 90&#176; flexion, the hip in neutral rotation and abduction, and the foot in plantar flexion.</li>
	<li>Place the participant&#39;s hands on their abdomen and stabilize the trunk, hips, and mid-thigh on the chair with Velcro straps.</li>
	<li>Run a practice trial for participants to get accustomed to the testing maneuver.</li>
	<li>Instruct the participant to extend their knee (exert pressure upwards on the pad) followed by flex (exert pressure downwards on the pad) to exert a maximum contraction on the command Go for 3 s.</li>
	<li>Provide verbal prompts and encouragement (&#34;Push&#34; for upwards and &#34;Pull&#34; for downwards) during the strength testing.</li>
	<li>Ensure that participants are aware they can stop the test immediately if they experience any unusual pain or discomfort.</li>
	<li>Allow participants to rest for 2 min.</li>
	<li>Repeat steps 3.1 - 3.12, three times for the left leg and right leg and record the data in newtons (N).</li>
	<li>Save all the data and export as a report for the analysis.</li>
</ol>

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The authors have nothing to disclose.

The contribution of this study is to accurately and comprehensively describe within one protocol the techniques for combined gait analysis and muscle strength testing that have not previously been described together.
In order to achieve accurate results for gait analysis, there are two areas that require maximum attention: 1) marker placements and 2) acclimatization time. The accuracy of the measured data is heavily dependent on the accuracy of the model used. The other key factors that affect...

The discipline of biomechanics primarily involves the study of stress, strain, loads and motion of biological systems - solid and fluid alike. It also involves the modelling of mechanical effects on the structure, size, shape and movement of the body1. For many years, developments in this field have improved our understanding of normal and pathologic gait, mechanics of neuromuscular control, and mechanics of growth and form2.
The main objective of this article is to present a comprehensive methodology on two of the latest technologies available to measure lower limb biomechanics of individuals. The gait analysis system measures and quantifies gait biomechanics by using a self-paced (SP) treadmill in combination with an augmented reality environment, which integrates a SP algorithm to regulate the treadmill&#39;s speed, as described by Sloot et al3. The muscle strength testing equipment is used as an assessment and a treatment tool for upper extremity rehabilitation4. This device can objectively assess a variety of physiological patterns of movement or job simulation tasks in isometric and isotonic modes. It is currently recognized as the gold standard for upper limb strength measurement5 but the evidence related specifically to the lower limb remains unclear. This paper explains the detailed protocol for completing an assessment of gait and isometric strength for the lower extremity.
Within biomechanical analysis, it is useful to combine assessments of functional performance (such as gait analysis) with specific tests of muscular performance. This is because whilst it may be assumed that increased muscle strength improves functional performance, this may not always be apparent6. This understanding is required for the improved future design of rehabilitation protocols and research strategies to assess these approaches.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>701 Small lever</td>
			<td>Baltimore Therapeutic Equipment Company (BTE)</td>
			<td>Not Available - Online link provided in description</td>
			<td>The unique attachment designed for the Primus RS to measure Knee Extension/Flexion - <a href="https://store.btetech.com/collections/primus/products/701-small-lever" target="_blank">https://store.btetech.com/collections/primus/products/701-small-lever</a></td>
		</tr>
		<tr>
			<td>D-Flow Software - Vresion 3.26</td>
			<td>Motekforce Link</td>
			<td>Not Available - Online link provided in description</td>
			<td>Software used to control GRAIL system - <a href="https://summitmedsci.co.uk/products/motek-dflow-hbm-software/" target="_blank">https://summitmedsci.co.uk/products/motek-dflow-hbm-software/</a></td>
		</tr>
		<tr>
			<td>Gait Offline Analysis (GOAT) - Version 2.3</td>
			<td>Motekforce Link</td>
			<td>Not Available - Online link provided in description</td>
			<td>Software used for the analysis of the gait parameters - <a href="https://www.motekmedical.com/product/grail/" target="_blank">https://www.motekmedical.com/product/grail/</a></td>
		</tr>
		<tr>
			<td>Gait Real-time Analysis Interactive Lab (GRAIL)</td>
			<td>Motekforce Link</td>
			<td>Not Available - Online link provided in description</td>
			<td>GRAIL system measures and quantifies gait biomechanics by using a virtual reality based self-paced (SP) treadmill - <a href="https://www.motekmedical.com/product/grail/" target="_blank">https://www.motekmedical.com/product/grail/</a></td>
		</tr>
		<tr>
			<td>Leg Pad for 701</td>
			<td>Baltimore Therapeutic Equipment Company (BTE)</td>
			<td>Not Available - Online link provided in description</td>
			<td>The unique attachment designed for the Primus RS to measure Knee Extension/Flexion - <a href="https://store.btetech.com/collections/primus/products/701-802-leg-pad" target="_blank">https://store.btetech.com/collections/primus/products/701-802-leg-pad</a></td>
		</tr>
		<tr>
			<td>Positioning Chair</td>
			<td>Baltimore Therapeutic Equipment Company (BTE)</td>
			<td>Not Available - Online link provided in description</td>
			<td>Participant Positioning Chair is designed for assessment and treatment of the lower exteremeties. The chair is designed for multiple positions. <a href="https://www.btetech.com/product/primus/" target="_blank">https://www.btetech.com/product/primus/</a></td>
		</tr>
		<tr>
			<td>Primus RS</td>
			<td>Baltimore Therapeutic Equipment Company (BTE)</td>
			<td>Not Available - Online link provided in description</td>
			<td>Primus RS equipment captures and reports real time objective data in Isotonic, Isometric, and Isokinetic resistance modes - <a href="https://www.btetech.com/wp-content/uploads/BTE-Rehabilitation-Equipment-PrimusRS-Brochure-1.pdf" target="_blank">https://www.btetech.com/wp-content/uploads/BTE-Rehabilitation-Equipment-PrimusRS-Brochure-1.pdf</a></td>
		</tr>
	</tbody>
</table>

lower limb biomechanical analysis of healthy participants

Biomechanical analysis techniques are useful in the study of human movement. The aim of this study was to introduce a technique for the lower limb biomechanical assessment in healthy participants using commercially available systems. Separate protocols were introduced for the gait analysis and muscle strength testing systems. To ensure maximum accuracy for gait assessment, attention should be given to the marker placements and self-paced treadmill acclimatization time. Similarly, participant positioning, a practice trial, and verbal encouragement are three critical stages in muscle strength testing. The current evidence suggests that the methodology outlined in this article may be effective for the assessment of lower limb biomechanics.

The mean and standard deviation of the spatial-temporal, kinematics, and kinetic gait parameters are given in Table 2. MVIC data for all 30 participants are summarized in Table 3. A typical set of data for the left and right side of one participant showing graphical representation of gait parameters is provided in Figure 4 and Figure 5, respectively.
<p class="jove_content" fo:keep-together.w...

Watch this Scientific Journal Video about Lower Limb Biomechanical Analysis of Healthy Participants at JoVE.com

Lower Limb Biomechanical Analysis of Healthy Participants

This article introduces a comprehensive experimental methodology on two of the latest technologies available to measure the lower limb biomechanics of individuals.

Biomechanical analysis techniques are useful in the study of human movement. The aim of this study was to introduce a technique for the lower limb ...

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8.9K Views.  Bournemouth University. This article introduces a comprehensive experimental methodology on two of the latest technologies available to measure the lower limb biomechanics of individuals.

Video: Lower Limb Biomechanical Analysis of Healthy Participants

Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology

We describe an in vitro method to measure bladder smooth muscle contractility, and its use for investigating physiological and pharmacological properties of the smooth muscle as well as changes induced by pathology. This method provides critical information for understanding bladder function while overcoming major methodological difficulties encountered in in vivo experiments, such as surgical and pharmacological manipulations that affect stability and survival of the preparations, the use of human tissue, and/or the use of expensive chemicals. It also provides a way to investigate the properties of each bladder component (i.e. smooth muscle, mucosa, nerves) in healthy and pathological conditions.
The urinary bladder is removed from an anesthetized animal, placed in Krebs solution and cut into strips. Strips are placed into a chamber filled with warm Krebs solution. One end is attached to an isometric tension transducer to measure contraction force, the other end is attached to a fixed rod. Tissue is stimulated by directly adding compounds to the bath or by electric field stimulation electrodes that activate nerves, similar to triggering bladder contractions in vivo. We demonstrate the use of this method to evaluate spontaneous smooth muscle contractility during development and after an experimental spinal cord injury, the nature of neurotransmission (transmitters and receptors involved), factors involved in modulation of smooth muscle activity, the role of individual bladder components, and species and organ differences in response to pharmacological agents. Additionally, it could be used for investigating intracellular pathways involved in contraction and/or relaxation of the smooth muscle, drug structure-activity relationships and evaluation of transmitter release.
The in vitro smooth muscle contractility method has been used extensively for over 50 years, and has provided data that significantly contributed to our understanding of bladder function as well as to pharmaceutical development of compounds currently used clinically for bladder management.

This manuscript presents a simple, yet powerful, in vitro method for evaluating smooth muscle contractility in response to pharmacological agents or nerve stimulation. Main applications are drug screening and understanding tissue physiology, pharmacology,&#160;and pathology.

We describe an in vitro method to measure bladder smooth muscle contractility, and its use for investigating physiological and pharmacological properties ...

Remote Limb Ischemic Preconditioning:  A Neuroprotective Technique in Rodents

Sublethal ischemia protects tissues against subsequent, more severe ischemia through the upregulation of endogenous mechanisms in the affected tissue. Sublethal ischemia has also been shown to upregulate protective mechanisms in remote tissues. A brief period of ischemia (5-10 min) in the hind limb of mammals induces self-protective responses in the brain, lung, heart and retina. The effect is known as remote ischemic preconditioning (RIP). It is a therapeutically promising way of protecting vital organs, and is already under clinical trials for heart and brain injuries. This publication demonstrates a controlled, minimally invasive method of making a limb &#8211; specifically the hind limb of a rat &#8211; ischemic. A blood pressure cuff developed for use in human neonates is connected to a manual sphygmomanometer and used to apply 160 mmHg pressure around the upper part of the hind limb. A probe designed to detect skin temperature is used to verify the ischemia, by recording the drop in skin temperature caused by pressure-induced occlusion of the leg arteries, and the rise in temperature which follows release of the cuff. This method of RIP affords protection to the rat retina against bright light-induced damage and degeneration.

Remote ischemic preconditioning (RIP) is a method of conditioning tissues against damaging stress. We have established a method of remote ischemia at the hind limb, by inflating a sphygmomanometer cuff for 5-10 min. The neuroprotective capabilities of RIP have been demonstrated in a model of retinal degeneration in rodents.

Sublethal ischemia protects tissues against subsequent, more severe ischemia through the upregulation of endogenous mechanisms in the affected tissue. ...

Orthotopic Hind Limb Transplantation in the Mouse

In vivo animal model systems, and in particular mouse models, have evolved into powerful and versatile scientific tools indispensable to basic and translational research in the field of transplantation medicine. A vast array of reagents is available exclusively in this setting, including mono- and polyclonal antibodies for both diagnostic and interventional applications. In addition, a vast number of genotyped, inbred, transgenic, and knock out strains allow detailed investigation of the individual contributions of humoral and cellular components to the complex interplay of an immune response and make the mouse the gold standard for immunological research. 
Vascularized Composite Allotransplantation (VCA) delineates a novel field of transplantation using allografts to replace "like with like" in patients suffering traumatic or congenital tissue loss. This surgical methodological protocol shows the use of a non-suture cuff technique for super-microvascular anastomosis in an orthotopic mouse hind limb transplantation model. The model specifically allows for comparison between established paradigms in solid organ transplantation with a novel form of transplants consisting of various different tissue components. Uniquely, this model allows for the transplantation of a viable vascularized bone marrow compartment and niche that have the potential to exert a beneficial effect on the balance of immune acceptance and rejection. This technique provides a tool to investigate alloantigen recognition and allograft rejection and acceptance, as well as enables the pursuit of functional nerve regeneration studies to further advance this novel field of transplantation.

This novel model for orthotopic hind limb transplantation in the mouse, applying a non-suture cuff technique for super-microvascular anastomosis, provides a powerful tool for in&#160;vivo mechanistic immunological research related to vascularized composite allotransplantation (VCA).

In vivo animal model systems, and in particular mouse models, have evolved into powerful and versatile scientific tools indispensable to basic and ...

TRUE Gene Silencing: Screening of a Heptamer-type Small Guide RNA Library for Potential Cancer Therapeutic Agents

TRUE gene silencing (termed after tRNase ZL-utilizing efficacious gene silencing) is one of the RNA-directed gene silencing technologies, which utilizes an artificial small guide RNA (sgRNA) to guide tRNA 3&#8242; processing endoribonuclease, tRNase ZL, to recognize a target RNA. sgRNAs can be taken up by cells without any transfection reagents and can downregulate their target RNA levels and/or induce apoptosis in human cancer cells. We have screened an sgRNA library containing 156 heptamer-type sgRNAs for the effect on viability of human myeloma and leukemia cells, and found that 20 of them can efficiently induce apoptosis in at least one of the cancer cell lines. Here we present a protocol for screening of a heptamer-type sgRNA library for potential therapeutic drugs against blood cancers. The protocol includes how to construct the sgRNA library, how to assess the effect of each sgRNA on cell viability, and how to further evaluate the effective sgRNAs by flow cytometry. Around 2,000 hits would be expected to be obtained by screening the full-scale sgRNA library composed of 16,384 heptamers.

Here we present a protocol for screening of a heptamer-type sgRNA library for potential therapeutic drugs against blood cancers.

TRUE gene silencing (termed after tRNase ZL-utilizing efficacious gene silencing) is one of the RNA-directed gene silencing technologies, which utilizes ...

Oral Biofilm Sampling for Microbiome Analysis in Healthy Children

Oral biofilm and its molecular analysis provide a basis for investigating various dental research and clinical questions. Knowledge of biofilm composition leads to a better understanding of cariogenic and periopathogenic mechanisms. Microbial changes taking place in the oral cavity during childhood are of interest for several reasons. The evolution of the child oral microbiota and shifts in its composition need to be analyzed further to understand and possibly prevent the onset of disease. At the same time, advanced knowledge of the natural composition of oral biofilm is needed. Early stages of caries-free permanent dentition with healthy gums provide a widely unaffected subgingival habitat that can serve as an in situ baseline for studying features of oral health and disease. Analysis of children's oral biofilm during different stages in life is thus an important theme in the field. Modern molecular analysis methods can provide comprehensive information about the bacterial diversity of such biofilms. To enable microbiota data comparison, it is important to standardize each step in the procedure for molecular data generation. This procedure spans from clinical sampling, Next Generation Sequencing (NGS), bioinformatic data processing, to taxonomic interpretation. One of the most critical factors here is biofilm sampling. Sampling in children is even more challenging in particular due to limited space in subgingival areas. We thus focus on the use of paper points for subgingival sampling. This article provides a detailed protocol for oral biofilm sampling of the subgingival sulcus, the mucosa, and saliva in children.

Changes in the oral microbiome throughout childhood are of growing interest. Comparison of different microbiome studies reveals a lack of standardized sampling protocols. Limited space makes sampling the sound subgingival sulcus of children challenging. Paper point sampling is presented here in detail as the method of choice for this area.

Oral biofilm and its molecular analysis provide a basis for investigating various dental research and clinical questions. Knowledge of biofilm composition ...

Assessment of the Efficacy of An Osteopathic Treatment in Infants with Biomechanical Impairments to Suckling

Breastfeeding can be challenging for mother-infant dyads experiencing biomechanical suckling difficulties. Although lactation consultants (LCs) all over the world have increased their skills in this field and can provide support to help position the infant at the breast, the impact of their intervention might be limited in the presence of stiff structures in the infants. Here we present a protocol for a randomized controlled trial to assess the efficacy of osteopathic treatment, coupled with lactation consultation, for infants&#39; biomechanical suckling difficulties. It proposes a set-up and a sequence of actions to ensure an optimal context for treatment, as well as a blinding of parents and LCs to the intervention. Data such as the infant&#39;s latch ability measured with the LATCH Assessment Tool, the mother&#39;s nipple pain with a visual analog scale (VAS), and the mother&#39;s perceptions are collected by LCs four times over a 10-day period. Osteopathic lesions are documented by the osteopath, using a standardized assessment grid. Structures of interest are coherent with the anatomical zones involved in latching onto the breast. This protocol also proposes a strategy to document systematically an osteopathic profile of infants with biomechanical suckling difficulties in their first weeks of life. The implementation of this protocol confirms its feasibility for osteopathic assessment and treatment and paves the way for future trials to further explore the efficacy of osteopathic techniques for infants with biomechanical suckling difficulties.

Osteopathy is an emerging field of clinical research. Here we present a protocol to assess the efficacy of an osteopathic intervention coupled with lactation consultation, in infants with biomechanical issues impeding breastfeeding.

Breastfeeding can be challenging for mother-infant dyads experiencing biomechanical suckling difficulties. Although lactation consultants (LCs) all over ...

Preclinical Model of Hind Limb Ischemia in Diabetic Rabbits

Peripheral vascular disease is a widespread clinical problem that affects millions of patients worldwide. A major consequence of peripheral vascular disease is the development of ischemia. In severe cases, patients can develop critical limb ischemia in which they experience constant pain and an increased risk of limb amputation. Current therapies for peripheral ischemia include bypass surgery or percutaneous interventions such as angioplasty with stenting or atherectomy to restore blood flow. However, these treatments often fail to the continued progression of vascular disease or restenosis or are contraindicated due to the overall poor health of the patient. A promising potential approach to treat peripheral ischemia involves the induction of therapeutic neovascularization to allow the patient to develop collateral vasculature. This newly formed network alleviates peripheral ischemia by restoring perfusion to the affected area. The most frequently employed preclinical model for peripheral ischemia utilizes the creation of hind limb ischemia in healthy rabbits through femoral artery ligation. In the past, however, there has been a strong disconnect between the success of preclinical studies and the failure of clinical trials regarding treatments for peripheral ischemia. Healthy animals typically have robust vascular regeneration in response to surgically induced ischemia, in contrast to the reduced vascularity and regeneration in patients with chronic peripheral ischemia. Here, we describe an optimized animal model for peripheral ischemia in rabbits that includes hyperlipidemia and diabetes. This model has reduced collateral formation and blood pressure recovery in comparison to a model with a higher cholesterol diet. Thus, the model may provide better correlation with human patients with compromised angiogenesis from the common co-morbidities that accompany peripheral vascular disease.

We describe a surgical procedure used to induce peripheral ischemia in rabbits with hyperlipidemia and diabetes. This surgery acts as a preclinical model for conditions experienced in peripheral artery disease in patients. Angiography is also described as a means to measure the extent of introduced ischemia and recovery of perfusion.

Peripheral vascular disease is a widespread clinical problem that affects millions of patients worldwide. A major consequence of peripheral vascular ...

The Lower Body Positive Pressure Treadmill for Knee Osteoarthritis Rehabilitation

Here, based on a clinician&rsquo;s point-of-view, we propose a two-model lower body positive pressure (LBPP) protocol (walking and squatting models) in addition to a clinical, functional assessment methodology, including details for further encouragement of the development of non-drug surgical intervention strategies in knee osteoarthritis patients. However, we only present the effect of LBPP training in improvement of pain and knee function in one patient through three-dimensional gait analysis. The exact, long-term effects of this approach should be explored in future studies.

Here, based on a clinician&#8217;s point-of-view, we propose a two-model lower body positive pressure (LBPP) protocol (walking and squatting models) in addition to a clinical, functional assessment methodology, including details for further encouragement of the development of non-drug surgical intervention strategies in knee osteoarthritis patients. However, we only present the effect of LBPP training in improvement of pain and knee function in one patient through three-dimensional gait analysis. The exact, long-term effects of this approach should be explored in future studies.

Here, based on a clinician&rsquo;s point-of-view, we propose a two-model lower body positive pressure (LBPP) protocol (walking and squatting models) in ...

Virtual Prism Adaptation Therapy: Protocol for Validation in Healthy Adults

Hemispatial neglect is a common impairment after stroke. It is associated with poor functional and social outcomes. Therefore, an adequate intervention is imperative for the successful management of hemispatial neglect. However, the clinical use of various interventions is limited in real clinical practice. Prism adaptation therapy is one of the most evidence-based rehabilitation modalities to treat hemispatial neglect. To overcome any possible shortcoming that may occur with prism therapy, we developed a new system using immersive virtual reality and depth-sensing camera to create a virtual prism adaptation therapy (VPAT). To validate the VPAT system, we designed an experimental protocol investigating the behavioral errors and changes in cortical activation via the VPAT system. Cortical activation was measured by functional near infrared spectroscopy (fNIRS). The experiment consisted of four phases. All four included clicking, pointing or rest applied to right-handed healthy people. Clicking versus pointing was used for investigating the cortical region related with the gross motor task, and pointing with VPAT versus pointing without VPAT was used for investigating the cortical region associated with visuospatial perception. The preliminary results from four healthy participants showed that pointing errors by the VPAT system was similar to the conventional prism adaptation therapy. Further analysis with more participants and fNIRS data, as well as a study in patients with stroke may be required.

This experimental protocol demonstrates the use of virtual prism adaptation therapy (VPAT) in healthy adults and the association between VPAT and functional near infrared spectroscopy to determine the effect of VPAT on cortical activation. Results suggest that VPAT may be feasible and could induce similar behavioral adaptation as conventional prism adaptation therapy.

Hemispatial neglect is a common impairment after stroke. It is associated with poor functional and social outcomes. Therefore, an adequate intervention is ...

On-Site Sampling and Extraction of Brain Tumors for Metabolomics and Lipidomics Analysis

Despite the variety of tools available for cancer diagnosis and classification, methods that enable fast and simple characterization of tumors are still in need. In recent years, mass spectrometry has become a method of choice for untargeted profiling of discriminatory compound as potential biomarkers of a disease. Biofluids are generally considered as preferable matrices given their accessibility and easier sample processing while direct tissue profiling provides more selective information about a given cancer. Preparation of tissues for the analysis via traditional methods is much more complex and time-consuming, and, therefore, not suitable for fast on-site analysis. The current work presents a protocol combining sample preparation and extraction of small molecules on-site, immediately after tumor resection. The sampling device, which is of the size of an acupuncture needle, can be inserted directly into the tissue and then transported to the nearby laboratory for instrumental analysis. The results of metabolomics and lipidomics analyses demonstrate the capability of the approach for the establishment of phenotypes of tumors related to the histological origin of the tumor, malignancy, and genetic mutations, as well as for the selection of discriminating compounds or potential biomarkers. The non-destructive nature of the technique permits subsequent performance of routinely used tests e.g., histological tests, on the same samples used for SPME analysis, thus enabling attainment of more comprehensive information to support personalized diagnostics.

The manuscript presents on-site sampling of human brain tumors with solid phase microextraction followed by their biochemical profiling towards the discovery of biomarkers.

Despite the variety of tools available for cancer diagnosis and classification, methods that enable fast and simple characterization of tumors are still ...