Biomimetic nanodrug targets inflammation and suppresses YAP/TAZ to ameliorate atherosclerosis.

Atherosclerosis, a chronic inflammatory disease, is the primary cause of myocardial infarction and ischemic stroke. Recent studies have demonstrated that dysregulation of yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding domain (TAZ) contributes to plaque development, making YAP/TAZ potential therapeutic targets. However, systemic modulation of YAP/TAZ expression or activities risks serious off-target effects, limiting clinical applicability. To address the challenge, this study develops monocyte membrane-coated nanoparticles (MoNP) as a targeted delivery system for activated and inflamed endothelium lining the plaque surface. The MoNP system is used to deliver verteporfin (VP), aimed at inhibiting YAP/TAZ specifically within arterial regions prone to atherosclerosis. The results reveal that MoNP significantly enhance payload delivery to inflamed endothelial cells (EC) while avoiding phagocytic cells. When administered in mice, MoNP predominantly accumulate in intima of the atheroprone artery. MoNP-mediated delivery of VP substantially reduces YAP/TAZ expression, thereby suppressing inflammatory gene expression and macrophage infiltration in cultured EC and mouse arteries exposed to atherogenic stimuli. Importantly, this targeted VP nanodrug effectively decreases plaque development in mice without causing noticeable histopathological changes in major organs. Collectively, these findings demonstrate a lesion-targeted and pathway-specific biomimetic nanodrug, potentially leading to safer and more effective treatments for atherosclerosis.

Impact of asymmetric electrodes on ferroelectricity of sub-10 nm HZO thin films.

In this study, platinum (Pt) and tungsten (W), two materials with dissimilar coefficients of thermal expansion (CTE) and work functions (WF), are used as the top electrode (TE) and the bottom electrode (BE) in metal/ferroelectric/metal (MFM) structures to explore the ferroelectricity of hafnium zirconium oxide (HZO) with a thickness less than 10 nm. The electrical measurements indicate that a higher CTE mismatch between HZO and TE/BE is beneficial for enhancing the ferroelectric properties of nanoscale HZO thin films. The different WFs of TE and BE generate a built-in electric field in the HZO layer, leading to shifts in the hysteresis loops and the capacitance-voltage characteristics. The structural characterizations reveal that the preferred formation of the orthorhombic phase in HZO is dominated by the W BE. The device in which W is used as the TE and BE (the W/HZO/W MFM structure) presents the optimal ferroelectric performance of a high remanent polarization (2Pr= 55.2µC cm-2). The presence of tungsten oxide (WOx) at the W/HZO interfaces, as revealed by high-resolution transmission microscopy, is also responsible for the enhancement of ferroelectric properties. This study demonstrates the significant effects of different CTEs and WFs of TE and BE on the properties of ferroelectric HZO thin films.

Sharp Transformation across Morphotropic Phase Boundary in Sub-6 nm Wake-Up-Free Ferroelectric Films by Atomic Layer Technology.

Atomic layer engineering is investigated to tailor the morphotropic phase boundary (MPB) between antiferroelectric, ferroelectric, and paraelectric phases. By increasing the HfO2 seeding layer with only 2 monolayers, the overlying ZrO2 layer experiences the dramatic phase transition across the MPB. Conspicuous ferroelectric properties including record-high remanent polarization (2Pr ≈ 60 µC cm-2 ), wake-up-free operation, and high compatibility with advanced semiconductor technology nodes, are achieved in the sub-6 nm thin film. The prominent antiferroelectric to ferroelectric phase transformation is ascribed to the in-plane tensile stress introduced into ZrO2 by the HfO2 seeding layer. Based on the high-resolution and high-contrast images of surface grains extracted precisely by helium ion microscopy, the evolution of the MPB between tetragonal, orthorhombic, and monoclinic phases with grain size is demonstrated for the first time. The result indicates that a decrease in the average grain size drives the crystallization from the tetragonal to polar orthorhombic phases.

Lesion-specific suppression of YAP/TAZ by biomimetic nanodrug ameliorates atherosclerosis development.

Atherosclerosis, characterized by the buildup of lipid-rich plaque on the vessel wall, is the primary cause of myocardial infarction and ischemic stroke. Recent studies have demonstrated that dysregulation of yes-associated protein 1 (YAP) and transcriptional coactivator with PDZ-binding domain (TAZ) contributes to plaque development, making YAP/TAZ potential therapeutic targets. However, systemic modulation of YAP/TAZ expression or activities risks serious off-target effects, limiting clinical applicability. To address the challenge, this study develops monocyte membrane-coated nanoparticles (MoNP) as a drug delivery vehicle targeting activated endothelium lining the plaque surface and utilizes MoNP to deliver verteporfin (VP), a potent YAP/TAZ inhibitor, for lesion-specific treatment of atherosclerosis. The results reveal that MoNP significantly enhance payload delivery to inflamed endothelial cells (EC) while avoiding phagocytic cells, and preferentially accumulate in atherosclerotic regions. MoNP-mediated delivery of VP substantially reduces YAP/TAZ expression, suppressing inflammatory gene expression and macrophage infiltration in cultured EC and mouse arteries exposed to atherogenic stimuli. Importantly, this lesion-targeted VP nanodrug effectively decreases plaque development in mice without causing noticeable histopathological changes in major organs. Collectively, these findings demonstrate a plaque-targeted and pathway-specific biomimetic nanodrug, potentially leading to safer and more effective treatments for atherosclerosis.

Upper-Arm Photoplethysmographic Sensor with One-Time Calibration for Long-Term Blood Pressure Monitoring.

Wearable cuffless photoplethysmographic blood pressure monitors have garnered widespread attention in recent years; however, the long-term performance values of these devices are questionable. Most cuffless blood pressure monitors require initial baseline calibration and regular recalibrations with a cuffed blood pressure monitor to ensure accurate blood pressure estimation, and their estimation accuracy may vary over time if left uncalibrated. Therefore, this study assessed the accuracy and long-term performance of an upper-arm, cuffless photoplethysmographic blood pressure monitor according to the ISO 81060-2 standard. This device was based on a nonlinear machine-learning model architecture with a fine-tuning optimized method. The blood pressure measurement protocol followed a validation procedure according to the standard, with an additional four weekly blood pressure measurements over a 1-month period, to assess the long-term performance values of the upper-arm, cuffless photoplethysmographic blood pressure monitor. The results showed that the photoplethysmographic signals obtained from the upper arm had better qualities when compared with those measured from the wrist. When compared with the cuffed blood pressure monitor, the means ± standard deviations of the difference in BP at week 1 (baseline) were -1.36 ± 7.24 and -2.11 ± 5.71 mmHg for systolic and diastolic blood pressure, respectively, which met the first criterion of ≤5 ± ≤8.0 mmHg and met the second criterion of a systolic blood pressure ≤ 6.89 mmHg and a diastolic blood pressure ≤ 6.84 mmHg. The differences in the uncalibrated blood pressure values between the test and reference blood pressure monitors measured from week 2 to week 5 remained stable and met both criteria 1 and 2 of the ISO 81060-2 standard. The upper-arm, cuffless photoplethysmographic blood pressure monitor in this study generated high-quality photoplethysmographic signals with satisfactory accuracy at both initial calibration and 1-month follow-ups. This device could be a convenient and practical tool to continuously measure blood pressure over long periods of time.

A Heterostructured Graphene Quantum Dots/ß-Ga2O3 Solar-Blind Photodetector with Enhanced Photoresponsivity.

The superior optical and electronic characteristics of quasi-two-dimensional ß-Ga2O3 make it suitable for solar-blind (200-280 nm) photodetectors (PDs). The metal-semiconductor-metal (MSM) PDs commonly suffer from low photoresponsivity, slow response speed, and a narrow detection wavelength range despite their simple fabrication process. Herein, we report a high-performance MSM PD by integrating exfoliated ß-Ga2O3 flakes with zero-dimensional graphene quantum dots (GQDs), which exhibits the advantages of enhancing the photoresponsivity, shortening the photoresponse time, and stimulating a broad range of photon detection. The hybrid GQDs/ß-Ga2O3 heterostructure PD is sensitive to deep-ultraviolet (DUV) light (250 nm) with an ultrahigh responsivity (R of ∼2.4 × 105 A/W), a large detectivity (D* of ∼4.3 × 1013 Jones), an excellent external quantum efficiency (EQE of ∼1.2 × 108%), and a fast photoresponse (150 ms), which is superior to the bare ß-Ga2O3 PD. These improvements result from effective charge transfer due to the introduction of GQDs, which enhance the light absorption and the generation of electron-hole pairs. In addition, the hybrid GQDs/ß-Ga2O3 PD also exhibits better photoelectric performance than the bare ß-Ga2O3 PD at a 1000 nm wavelength. As a conclusion, the hybrid GQDs/ß-Ga2O3 DUV photodetector shows potential applications in commercial optoelectronic products and provides an alternative solution for the design and preparation of high-performance photodetectors.

Solution-Processed Organic Photodetectors with Renewable Materials.

An organic photodetector prepared by a simple solution method based on renewable citrus pectin with an optimized concentration of aluminum nitrate (AlC05) is introduced herein. The effects of different concentrations of aluminum nitrate on the morphology and optical properties were investigated through various characterization methods. An AlC concentration of 0.5 mg/mL was found to provide the highest on/off ratio and acceptable rise and decay times. Also, the optimized device (Al/AlC0.5/ITO) exhibited good stability and repeatability at a 0.1 V bias under 440 nm visible light. Based on these results, citrus pectin materials were successfully used to fabricate an organic photodetector with a simple and cost-efficient fabrication process, while taking into account environmental commitments.

Maintenance of HDACs and H3K9me3 Prevents Arterial Flow-Induced Venous Endothelial Damage.

The transition of flow microenvironments from veins to arteries in vein graft surgery induces "peel-off" of venous endothelial cells (vECs) and results in restenosis. Recently, arterial laminar shear stress (ALS) and oscillatory shear stress (OS) have been shown to affect the cell cycle and inflammation through epigenetic controls such as histone deacetylation by histone deacetylases (HDACs) and trimethylation on lysine 9 of histone 3 (H3K9me3) in arterial ECs. However, the roles of H3K9me3 and HDAC in vEC damage under ALS are not known. We hypothesized that the different responses of HDACs and H3K9me3 might cause vEC damage under the transition of venous flow to arterial flow. We found that arterial ECs showed high expression of H3K9me3 protein and were retained in the G0 phase of the cell cycle after being subjected to ALS. vECs became round under ALS with a decrease in the expression of H3K9me3, HDAC3, and HDAC5, and an increase in the expression of vascular cell adhesion molecule 1 (VCAM-1). Inhibition of HDACs activity by a specific inhibitor, phenylbutyrate, in arterial ECs caused similar ALS-induced inflammation and cell loss as observed in vECs. Activation of HDACs and H3K9me3 by ITSA-1, an HDAC activator, could prevent ALS-induced peel-off and reduced VCAM-1 expression in vECs. Moreover, shear stress modulates EC morphology by the regulation of focal adhesion kinase (FAK) expression. ITSA-1 or EGF could increase phosphorylated (p)-FAK expression in vECs under ALS. We found that perturbation of the activity of p-FAK and increase in p-FAK expression restored ALS-induced H3K9me3 expression in vECs. Hence, the abnormal mechanoresponses of H3K9me3 and HDAC in vECs after being subjected to ALS could be reversed by ITSA-1 or EGF treatment: this offers a strategy to prevent vein graft failure.

Impact of Top Electrodes on the Nonvolatile Resistive Switching Properties of Citrus Thin Films.

Natural citrus thin films on an indium tin oxide (ITO)/glass substrate were synthesized using the solution method for resistive random access memory (RRAM) applications. The results indicated that the citrus memory device possessed stable resistive switching behavior. For a clear understanding of the role of the interface reaction between the top metal electrode and the citrus film, we investigated the influences of various top electrode (TE) materials on the resistive switching in TE/citrus/ITO devices. In comparison with Au/citrus/ITO and Ti/citrus/ITO devices, the Al/citrus/ITO device can be reproduced with a DC voltage of more than 100 times while only showing a slight decrease in the ON/OFF ratio. In addition, the Al/citrus/ITO device exhibited a high ON/OFF ratio of over 104 and an outstanding uniformity, which was attributed to the fast formation of a native oxide layer (AlOx), as confirmed by the line scan analysis. This indicated that the interface layer, created by the redox reaction between the Al electrode and citrus film, played an important role in the resistive switching properties of TE/citrus/ITO structures. These findings can serve as design guidelines for future bio-based RRAM devices.

The effects of gait training using powered lower limb exoskeleton robot on individuals with complete spinal cord injury.

BACKGROUND: Powered exoskeleton can improve the mobility for people with movement deficits by providing mechanical support and facilitate the gait training. This pilot study evaluated the effect of gait training using a newly developed powered lower limb exoskeleton robot for individuals with complete spinal cord injury (SCI). METHODS: Two participants with a complete SCI were recruited for this clinical study. The powered exoskeleton gait training was 8 weeks, 1 h per session, and 2 sessions per week. The evaluation was performed before and after the training for (1) the time taken by the user to don and doff the powered exoskeleton independently, (2) the level of exertion perceived by participants while using the powered exoskeleton, and (3) the mobility performance included the timed up-and-go test, 10-m walk test, and 6-min walk test with the powered exoskeleton. The safety of the powered exoskeleton was evaluated on the basis of injury reports and the incidence of falls or imbalance while using the device. RESULTS: The results indicated that the participants were donning and doffing the powered lower limb exoskeleton robot independently with a lower level of exertion and walked faster and farther without any injury or fall incidence when using the powered exoskeleton than when using a knee-ankle-foot orthosis. Bone mineral densities was also increased after the gait training. No adverse effects, such as skin abrasions, or discomfort were reported while using the powered exoskeleton. CONCLUSIONS: The findings demonstrated that individuals with complete SCI used the powered lower limb exoskeleton robot independently without any assistance after 8 weeks of powered exoskeleton gait training. TRIAL REGISTRATION: Trial registration: National Taiwan University Hospital. TRIAL REGISTRATION NUMBER: 201210051RIB . Name of registry: Hui-Fen Mao. URL of registry: Not available. Date of registration: December 12th, 2012. Date of enrolment of the first participant to the trial: January 3rd, 2013.

Relevance of nerve conduction velocity in the assessment of balance performance in older adults with diabetes mellitus.

Purpose This study investigated the relationship between peripheral nerve conduction velocity (NCV) and balance performance in older adults with diabetes. Methods Twenty older adults with diabetes were recruited to evaluate the NCV of their lower limbs and balance performance. The balance assessments comprised the timed up and go (TUG) test, Berg balance scale (BBS), unipedal stance test (UST), multidirectional reach test (MDRT), maximum step length (MSL) test and quiet standing with eyes open and closed. The relationship between NCV and balance performance was evaluated by Pearson's correlation coefficients, and the balance performances of the diabetic patients with and without peripheral neuropathy were compared by using Mann-Whitney U tests. Results The NCV in the lower limbs exhibited a moderate to strong correlation with most of the balance tests including the TUG (r = -0.435 to -0.520, p < 0.05), BBS (r = 0.406-0.554, p < 0.05), UST (r = 0.409-0.647, p < 0.05) and MSL (r = 0.399-0.585, P < 0.05). In addition, patients with diabetic peripheral neuropathy had a poorer TUG (p < 0.05), BBS (p < 0.01), UST (p < 0.05) and MSL performance (p < 0.05) compared with those without peripheral neuropathy (p < 0.05). Conclusion Our findings revealed that a decline in peripheral nerve conduction in the lower limb is not only an indication of nerve dysfunction, but may also be related to the impairment of balance performance in patients with diabetes. Implications for Rehabilitation Nerve conduction velocity in the lower limbs of diabetic older adults showed moderate to strong correlations with most of the results of balance tests, which are commonly used in clinics. Decline in nerve conduction velocity of the lower limbs may be related to the impairment of balance control in patients with diabetes. Diabetic older adults with peripheral neuropathy exhibited greater postural instability than those without peripheral neuropathy.

Critical Assessment of the Important Residues Involved in the Dimerization and Catalysis of MERS Coronavirus Main Protease.

BACKGROUND: A highly pathogenic human coronavirus (CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), has emerged in Jeddah and other places in Saudi Arabia, and has quickly spread to European and Asian countries since September 2012. Up to the 1st October 2015 it has infected at least 1593 people with a global fatality rate of about 35%. Studies to understand the virus are necessary and urgent. In the present study, MERS-CoV main protease (Mpro) is expressed; the dimerization of the protein and its relationship to catalysis are investigated. METHODS AND RESULTS: The crystal structure of MERS-CoV Mpro indicates that it shares a similar scaffold to that of other coronaviral Mpro and consists of chymotrypsin-like domains I and II and a helical domain III of five helices. Analytical ultracentrifugation analysis demonstrated that MERS-CoV Mpro undergoes a monomer to dimer conversion in the presence of a peptide substrate. Glu169 is a key residue and plays a dual role in both dimerization and catalysis. The mutagenesis of other residues found on the dimerization interface indicate that dimerization of MERS-CoV Mpro is required for its catalytic activity. One mutation, M298R, resulted in a stable dimer with a higher level of proteolytic activity than the wild-type enzyme. CONCLUSIONS: MERS-CoV Mpro shows substrate-induced dimerization and potent proteolytic activity. A critical assessment of the residues important to these processes provides insights into the correlation between dimerization and catalysis within the coronaviral Mpro family.

The adaptive changes in muscle coordination following lumbar spinal fusion.

Limited back motion and damage of paraspinal muscles after spinal fusion surgery may lead to abnormal compensatory movements of the body. Whether neuromuscular control changes after surgery remains unclear. The purpose of the study was to identify the muscle activation patterns employed before and after lumbar spinal fusion. Nineteen patients having low back pain and undergoing minimally invasive lumbar spinal fusion were evaluated at 1 day before and 1 month after fusion surgery. Nineteen matched healthy participants were recruited as controls. Patients' pain severity and daily activity functioning were recorded. All participants were instructed to perform forward reaching, and the muscle activities were monitored using surface electromyography (EMG) with sensors placed on both sides of their trunk and lower limbs. The muscle activation patterns were identified using the principal component analysis (PCA). All patients had significant improvements in pain intensity and daily activity functioning after surgery, but exhibited an adaptive muscle activation pattern during forward reaching movement compared with the controls. Significant loading coefficients in the dominant movement pattern (reflected in the first principal component) were observed in back muscles for controls whereas in leg muscles for patients, both pre- and postoperatively. Despite substantial improvements in pain intensity and daily activity functioning after surgery, the patients exhibited decreased paraspinal muscle activities and adaptive muscle coordination patterns during forward reaching. They appeared to rely mainly on their leg muscles to compensate for their insufficient paraspinal muscle function. Early intervention focusing on training paraspinal muscles should be considered after spinal fusion surgery.

Reduced intensity in gait-slip training can still improve stability.

Perturbation training with "free" slips (i.e., with long slip distance) has been able to successfully improve stability and to reduce the incidence of falls among older adults. Yet, it is unclear whether a highly constrained training with reduced slip distance (and hence training intensity) can achieve similar effects. The purpose of this study was to investigate whether short-distance slips could also improve the control of stability, and whether such improvements could be generalized to a novel, "free" slip. Thirty-six young subjects were randomly assigned to either one of the two training groups, which underwent seven training trials with constrained slips of either 12-cm or 18-cm in distance before encountering a novel, "free" slip (up to 150 cm) in the test trial; or the control group, which only experienced the same test trial of a novel, "free" slip. The results showed that while both training groups were able to significantly improve their control of stability in training; the 18-cm group had significantly better reactive control of stability than the 12-cm group. During the "free" slip, such advantage enabled the 18-cm group to exhibit significantly less balance loss incidence than 12-cm group (58.3 vs. 83.3%) and the controls (100%). These differences could be fully accounted for when we assume that the central nervous system directly controls slip velocity or slip distance during adaptation, whereby the level of similarity between training trials and the test trial governs the degree of generalization. The findings that low intensity training may still improve stability warrant further investigations among older adults.

A gene expression signature of epithelial tubulogenesis and a role for ASPM in pancreatic tumor progression.

BACKGROUND & AIMS: Many patients with pancreatic ductal adenocarcinoma (PDAC) develop recurrent or metastatic diseases after surgery, so it is important to identify those most likely to benefit from aggressive therapy. Disruption of tissue microarchitecture is an early step in pancreatic tumorigenesis and a parameter used in pathology grading of glandular tumors. We investigated whether changes in gene expression during pancreatic epithelial morphogenesis were associated with outcomes of patients with PDAC after surgery. METHODS: We generated architectures of human pancreatic duct epithelial cells in a 3-dimensional basement membrane matrix. We identified gene expression profiles of the cells during different stages of tubular morphogenesis (tubulogenesis) and of PANC-1 cells during spheroid formation. Differential expression of genes was confirmed by immunoblot analysis. We compared the gene expression profile associated with pancreatic epithelial tubulogenesis with that of PDAC samples from 27 patients, as well as with their outcomes after surgery. RESULTS: We identified a gene expression profile associated with tubulogenesis that resembled the profile of human pancreatic tissue with differentiated morphology and exocrine function. Patients with PDACs with this profile fared well after surgery. Based on this profile, we established a 6-28 gene tubulogenesis-specific signature that accurately determined the prognosis of independent cohorts of patients with PDAC (total n = 128; accuracy = 81.2%-95.0%). One gene, ASPM, was down-regulated during tubulogenesis but up-regulated in human PDAC cell lines and tumor samples; up-regulation correlated with patient outcomes (Cox regression P = .0028). Bioinformatic, genetic, biochemical, functional, and clinical correlative studies showed that ASPM promotes aggressiveness of PDAC by maintaining Wnt-ß-catenin signaling and stem cell features of PDAC cells. CONCLUSIONS: We identified a gene expression profile associated with pancreatic epithelial tubulogenesis and a tissue architecture-specific signature of PDAC cells that is associated with patient outcomes after surgery.

Molecular profiling of prostatic acinar morphogenesis identifies PDCD4 and KLF6 as tissue architecture-specific prognostic markers in prostate cancer.

Histopathological classification of human prostate cancer (PCA) relies on the morphological assessment of tissue specimens but has limited prognostic value. To address this deficiency, we performed comparative transcriptome analysis of human prostatic acini generated in a three-dimensional basement membrane that recapitulates the differentiated morphological characteristics and gene expression profile of a human prostate glandular epithelial tissue. We then applied an acinar morphogenesis-specific gene profile to two independent cohorts of patients with PCA (total n = 79) and found that those with tumors expressing this profile, which we designated acini-like tumors, had a significantly lower risk of postoperative relapse compared with those tumors with a lower correlation (hazard ratio, 0.078; log-rank test P = 0.009). Multivariate analyses showed superior prognostic prediction performance using this classification system compared with clinical criteria and Gleason scores. We prioritized the genes in this profile and identified programmed cell death protein 4 (PDCD4) and Kruppel-like factor 6 (KLF6) as critical regulators and surrogate markers of prostatic tissue architectures, which form a gene signature that robustly predicts clinical prognosis with a remarkable accuracy in several large series of PCA tumors (total n = 161; concordance index, 0.913 to 0.951). Thus, by exploiting the genomic program associated with prostate glandular differentiation, we identified acini-like PCA and related molecular markers that significantly enhance prognostic prediction of human PCA.

Adaptive control reduces trip-induced forward gait instability among young adults.

A vital functional plasticity of humans is their ability to adapt to threats to posture stability. The purpose of this study was to investigate adaptation to repeated trips in walking. Sixteen young adults were recruited and exposed to the sudden (electronic-mechanical) release of an obstacle, 11-cm in height, in the path of over ground walking during the mid-to-late left swing phase. Although none of the subjects fell on the first of eight unannounced, consecutive trips, all of them had to rely on compensatory step with a step length significantly longer than their regular to reduce their instability. In the subsequent trials, they were able to rapidly make adaptive adjustments in the control of their center-of-mass (COM) stability both proactively and reactively (i.e., before and after hitting or crossing the obstacle), such that the need for taking compensatory step was substantially diminished. The proactive adaptations included a reduced forward COM velocity that lessened forward instability in mid-to-late stance and an elevated toe clearance that reduced the likelihood of obstacle contact. The reactive adjustments were characterized by improved trunk control (by reducing its forward rotation) and limb support (by increasing hip height), and reduced forward instability (by both the posterior COM shift and the reduction in its forward velocity). These findings suggest that young adults can adapt appropriately to repeated trip perturbations and to reduce trip-induced excessive instability in both proactive and reactive manners.

Sensitivity of plantar cutaneous sensation and postural stability.

BACKGROUND: Impaired plantar cutaneous sensation is often seen clinically and can lead to postural instability. It is not clear if the severity of such sensory loss would be associated with postural stability, and if such an association would be affected by sensory redundancy and task difficulty. The purpose of this study was to investigate the association of the degree of somatosensory loss and postural stability by experimentally induced somatosensory loss in healthy young adults. METHODS: Twenty-one healthy young adults performed four quiet standing tasks (normal or narrow base, and eyes open or closed) on a force platform under three somatosensory conditions induced by ischemic blocking of afferent conduction below the ankle, normal, partial loss and complete loss. Differences in the standing center of pressure motion between the three sensory loss conditions were compared. FINDINGS: There was a significant trend of greater center of pressure motion with increasing severity of sensory loss in all task conditions. The differences in the center of pressure motion between partial and total loss conditions were significant only in conditions where vision was removed and the support surface was narrow. INTERPRETATION: Increased severity of experimentally induced loss of plantar cutaneous sensitivity was associated with greater postural sway. Such an association was affected by the availability of visual input and the size of the support surface. Clinically for patients with somatosensory impairments of the foot, postural stability should be given special attention.