Dual Barrier Research Articles

Müller Glia Co-Regulate Barrier Permeability with Endothelial Cells in an Vitro Model of Hyperglycemia.

Diabetic retinopathy is a complex, microvascular disease that impacts millions of working adults each year. High blood glucose levels from Diabetes Mellitus lead to the accumulation of advanced glycation end-products (AGEs), which promote inflammation and the breakdown of the inner blood retinal barrier (iBRB), resulting in vision loss. This study used an in vitro model of hyperglycemia to examine how endothelial cells (ECs) and Müller glia (MG) collectively regulate molecular transport. Changes in cell morphology, the expression of junctional proteins, and the reactive oxygen species (ROS) of ECs and MG were examined when exposed to a hyperglycemic medium containing AGEs. Trans-endothelial resistance (TEER) assays were used to measure the changes in cell barrier resistance in response to hyperglycemic and inflammatory conditions, with and without an anti-VEGF compound. Both of the cell types responded to hyperglycemic conditions with significant changes in the cell area and morphology, the ROS, and the expression of the junctional proteins ZO-1, CX-43, and CD40, as well as the receptor for AGEs. The resistivities of the individual and dual ECs and MG barriers decreased within the hyperglycemia model but were restored to that of basal, normoglycemic levels when treated with anti-VEGF. This study illustrated significant phenotypic responses to an in vitro model of hyperglycemia, as well as significant changes in the expression of the key proteins used for cell-cell communication. The results highlight important, synergistic relationships between the ECs and MG and how they contribute to changes in barrier function in combination with conventional treatments.

Piezoelectric-Enhanced Nanocatalysts Trigger Neutrophil N1 Polarization against Bacterial Biofilm by Disrupting Redox Homeostasis.

Strategies of manipulating redox signaling molecules to inhibit or activate immune signals have revolutionized therapeutics involving reactive oxygen species (ROS). However, certain diseases with dual resistance barriers to the attacks by both ROS and immune cells, such as bacterial biofilm infections of medical implants, are difficult to eradicate by a single exogenous oxidative stimulus due to the diversity and complexity of the redox species involved. Here, this work demonstrates that metal-organic framework (MOF) nanoparticles capable of disrupting the bacterial ROS-defense system can dismantle bacterial redox resistance and induce potent antimicrobial immune responses in a mouse model of surgical implant infection by simultaneously modulating redox homeostasis and initiating neutrophil N1 polarization in the infection microenvironment. Mechanistically, the piezoelectrically enhanced MOF triggers ROS production by tilting the band structure and acts synergistically with the aurintricarboxylic acid loaded within the MOF, which inhibits the activity of the cystathionine γ-cleaving enzyme. This leads to biofilm structure disruption and antigen exposure through homeostatic imbalance and synergistic activation of neutrophil N1 polarization signals. Thus, this study provides an alternative but promising strategy for the treatment of antibiotic-resistant biofilm infections.

Migrant Women in the UK’s Digital Economy: The Elimination of Labour Market Barriers in the Digital Labour Market

This research paper delves into the complexities migrant women face within the UK labour market, with a specific focus on the digital economy’s role as both a barrier and a conduit for employment opportunities. Migrant women in the UK encounter dual barriers to labour market entry: systemic challenges rooted in migration and gender biases, and the digital divide that exacerbates access and inclusion issues within the burgeoning digital economy. Through an exploratory descriptive analysis, this study explores how digitalism—defined as the integration of digital technologies into economic and societal practices—circumvents traditional labour market entry barriers such as languages barriers. By setting out the grounds for a potential hypothesis and further research in the era of AI, this paper underlines how through the implementation of AI tools, traditional barriers such as language barriers are eliminated in the digital labour market.

One-step fabrication of robust PDMS-MWCNTs composite superhydrophobic coatings with hierarchical micro-nanostructures for anticorrosive applications

Superhydrophobic coatings hold considerable promise for safeguarding metals against corrosion. However, realizing coatings with excellent superhydrophobicity, mechanical strength and corrosion resistance remains a great challenge. In this study, a robust superhydrophobic surface was achieved through the laser processing of multi walled carbon nanotubes (MWCNTs)/polydimethylsiloxane (PDMS) coatings, resulting in a water contact angle (WCA) of approximately 165°. Notably, the coating demonstrated outstanding abrasion resistance in sandpaper abrasion, steel wool abrasion, and falling sand tests. The friction coefficient of the coating is only 0.25. In addition, the robust superhydrophobic coating also has good anti-corrosion. The lowest-frequency impedance value of the composite coatings increases seven orders of magnitude compared with that of carbon steel, and the corrosion inhibition efficiency (η) is 99.83 %. The outstanding corrosion resistance is primarily ascribed to the formation of a dual synergistic barrier by PDMS-MWCNTs, providing effective protection for carbon steel.

Dihydroartemisinin Modulates Enteric Glial Cell Heterogeneity to Alleviate Colitis.

The precise mechanism underlying the therapeutic effects of dihydroartemisinin (DHA) in alleviating colitis remains incompletely understood. A strong correlation existed between the elevation of glial fibrillary acidic protein (GFAP)+/S100 calcium binding protein B (S100β)+ enteric glial cells (EGCs) in inflamed colonic tissues and the disruption of the intestinal epithelial barrier (IEB) and gut vascular barrier (GVB) observed in chronic colitis. DHA demonstrated efficacy in restoring the functionality of the dual gut barrier while concurrently attenuating intestinal inflammation. Mechanistically, DHA inhibited the transformation of GFAP+ EGCs into GFAP+/S100β+ EGCs while promoting the differentiation of GFAP+/S100β+ EGCs back into GFAP+ EGCs. Furthermore, DHA induced apoptosis in GFAP+/S100β+ EGCs by inducing cell cycle arrest at the G0/G1 phase. The initial mechanismis further validated that DHA regulates EGC heterogeneity by improving dysbiosis in colitis. These findings underscore the multifaceted therapeutic potential of DHA in ameliorating colitis by improving dysbiosis, modulating EGC heterogeneity, and preserving gut barrier integrity, thus offering promising avenues for novel therapeutic strategies for inflammatory bowel diseases.

A New Overflow Number for Analyzing and Designing Dual Rigid Barriers with Basal Clearance

A New Overflow Number for Analyzing and Designing Dual Rigid Barriers with Basal Clearance

Super-slippery silicone-based gel coating with a regenerative oil layer for long-term prevention of surface contamination

Polymer-based gel-type coatings, in which oil molecules are absorbed within polymer networks, have drawn attention as functional coatings to address fouling problems. However, surface drought caused by lubricant depletion limits the longevity of conventional gel-type coatings. In this study, a super-slippery long-chain entangled polydimethylsiloxane (LEP) gel that can self-regenerate a low-viscosity oil layer is proposed to enhance its long-term anti-fouling performance in both indoor and marine habitats. The proposed LEP gel coating can effectively prevent contamination from numerous liquids and protect aluminum surfaces from corrosion in seawater. Even when it was incubated with Porphyridium purpureum, marine red algae that readily stick to the surface, no biofilm was formed on the coated samples for 37 weeks. In field tests, no biological adhesion was observed on the coating surface which was applied to port structures and left for two summer months. This enhanced anti-contamination performance is mainly attributed to the dual protective barrier comprising the underlying polymer layer and regenerative oil layer. Due to special property of continuous self-regeneration of oil layer, the proposed LEP gel surface demonstrates much enhanced sustainability, compared to conventional gel-type coatings. Consequently, the long-term anti-contamination performance of the super-slippery LEP gel coating would pave the way for novel approach to its practical applications.

Wheat germ agglutinin modified mixed micelles overcome the dual barrier of mucus/enterocytes for effective oral absorption of shikonin and gefitinib.

The combination of shikonin (SKN) and gefitinib (GFB) can reverse the drug resistance of lung cancer cells by affecting energy metabolism. However, the poor solubility of SKN and GFB limits their clinical application because of low bioavailability. Wheat germ agglutinin (WGA) can selectively bind to sialic acid and N-acetylglucosamine on the surfaces of microfold cells and enterocytes, and is a targeted biocompatible material. Therefore, we created a co-delivery micelle system called SKN/GFB@WGA-micelles with the intestinal targeting functions to enhance the oral absorption of SKN and GFB by promoting mucus penetration for nanoparticles via oral administration. In this study, Caco-2/HT29-MTX-E12 co-cultured cells were used to simulate a mucus/enterocyte dual-barrier environment, and HCC827/GR cells were used as a model of drug-resistant lung cancer. We aimed to evaluate the oral bioavailability and anti-tumor effect of SKN and GFB using the SKN/GFB@WGA-micelles system. In vitro and in vivo experimental results showed that WGA promoted the mucus penetration ability of micelles, significantly enhanced the uptake efficiency of enterocytes, improved the oral bioavailability of SKN and GFB, and exhibited good anti-tumor effects by reversing drug resistance. The SKN/GFB@WGA-micelles were stable in the gastrointestinal tract and provided a novel safe and effective drug delivery strategy.

Multi-interfaced Ni/C@RGO/PTFE composites for electromagnetic protection applications with high environmental stability and durability

To efficiently address the growing electromagnetic pollution problem, it is urgently required to research high-performance electromagnetic materials that can effectively absorb or shield electromagnetic waves. In addition, the stability and durability of electromagnetic materials in complex practical environments is also an issue that needs to be noticed. Therefore, the starting point for our problem-solving is how to endow magnetic/dielectric multi-interfaced composite materials with excellent electromagnetic protection capability and environmental stability. In this study, magnetic/dielectric multi-interfaced Ni/carbon@reduced graphene oxide/polytetrafluoroethylene (Ni/C@RGO/PTFE) composites were developed to utilize as excellent EWA (electromagnetic wave absorption) and EMI (electromagnetic interference) shielding materials. Due to their diverse heterogeneous interfaces, rich conductive networks, and multiple loss mechanisms, the Ni/C@RGO/PTFE composite exhibits an optimal reflection loss of −61.48 dB and an effective absorption bandwidth of 7.20 GHz, with a filler loading of 5 wt%. Furthermore, Ni/C@RGO/PTFE composite films have an optimal absorption effectiveness value of 9.50 dB and an absorption coefficient of 0.49. Moreover, Ni/C@RGO/PTFE can hold high EWA performance in various corrosive media and maintain more than 90% of EMI shielding effectiveness, which can be attributed to the carbon coating and PTFE matrix acting as dual protective barriers for the susceptible metal Ni, thus obviously improving the stability and durability of composites. Overall, this work presents an effective strategy for the growth of high-performance EWA and EMI shielding materials with outstanding environmental stability and durability, which have wide application prospects in the future.

Engineered liposomes targeting hepatic stellate cells overcome pathological barriers and reverse liver fibrosis

Dual pathological barriers, including capillarized liver sinusoidal endothelial cells (LSECs) and deposited extracellular matrix (ECM), result in insufficient drug delivery, significantly compromising the anti-fibrosis efficacy. Additionally, excessive reactive oxygen species (ROS) in the hepatic microenvironment are crucial factors contributing to the progression of liver fibrosis. Hence, hyaluronic acid (HA) modified liposomes co-delivering all-trans retinoic acid (RA) and L-arginine (L-arg) were constructed to reverse hepatic fibrosis. By exhibiting exceptional responsiveness to the fibrotic microenvironment, our cleverly constructed liposomes efficiently disrupted the hepatic sinus pathological barrier, leading to enhanced accumulation of liposomes in activated hepatic stellate cells (HSCs) and subsequent induction of HSCs quiescence. Specially, excessive ROS in liver fibrosis promotes the conversion of loaded L-arg to nitric oxide (NO). The ensuing NO serves to reestablish the fenestrae structure of capillarized LSECs, thereby augmenting the likelihood of liposomes reaching the hepatic sinus space. Furthermore, subsequent oxidation of NO by ROS into peroxynitrite activates pro-matrix metalloproteinases into matrix metalloproteinases, which further disrupts the deposited ECM barrier. Consequently, this NO-induced cascade process greatly amplifies the accumulation of liposomes within activated HSCs. More importantly, the released RA could induce quiescence of activated HSCs by significantly downregulating the expression of myosin light chain-2, thereby effectively mitigating excessive collagen synthesis and ultimately leading to the reversal of liver fibrosis. Overall, this integrated systemic strategy has taken a significant step forward in advancing the treatment of liver fibrosis.

Dual External Electron Injection Barrier Layers Enable High‐Performance Near‐Infrared Organic Photodetectors Realizing Real‐Time Heart Rate Monitoring

AbstractNear‐infrared organic photodetectors (NIR‐OPDs) play important roles in medical monitoring, bio‐imaging and night vision, etc. Among them, bulk heterojunction (BHJ)‐based photodiode type NIR‐OPDs exhibit extraordinary characteristics in photoresponse and photosensitivity. However, their dark current density (Jd) often increases severely as the bias voltage increases, which seriously reduces detection sensitivity for NIR light. Here, a novel structure of dual external electron injection barrier layers (DEBLs) composed of “m‐MTDATA/DPEPO:HAT‐CN” is proposed to overcome this challenge. For DEBLs, a barrier is established with high injection barrier and long effective injection barrier width to prevent external electrons injection under bias voltage for suppressing Jd (4.22 × 10−8 A cm−2 better than 1.47 × 10−5 A cm−2 of the traditional device at −2 V). More importantly, photo‐generated carriers have almost no loss through DEBLs. Therefore, high and stable detectivity (D*) over 1013 Jones are realized under 850 nm from 0 V to nearly −1 V and even far over 1012 Jones at −2 V. More strikingly, the structure of DEBLs is proven to be effective and universal in NIR‐OPDs and the device based on it successfully realize the real‐time heart rate monitoring of various human states, which exhibits great potential in human health monitoring.

Eco-Friendly Fumed Nanosilica@Nanodiamond Hybrid Nanoparticles with Dual Sustainable Self-Healing and Barrier Anticorrosive Performances in Epoxy Coating.

Fumed nanosilica@nanodiamond attached by APTES [(3-aminopropyl) triethoxysilane], named FSiO2@sND, was examined as an efficient anticorrosive nanohybrid for epoxy coating. Compared with fumed nanosilica (FSiO2), nanodiamond (ND) moderated the hydrophilic nature of FSiO2@sND and offered additional functional groups to the nanohybrid, i.e., carboxylic groups of ND and functional groups of APTES, while retaining the eco-friendly nature of FSiO2 in the hybrid nanoparticle. The hybrid nanoparticle showed pH-sensitive release behavior in which APTES is released considerably in an alkaline medium, acting as an efficient corrosion inhibitor. A thorough electrochemical impedance spectroscopy (EIS) study of scratched coatings in a 3.5% NaCl solution disclosed that FSiO2@sND nanoparticles (at 0.33 wt % loading) conferred significant active/self-healing anticorrosion properties for the epoxy coatings, thanks to the release of APTES and the presence of carboxylic groups of ND taking part in forming a stable protective film on the substrate. Accordingly, epoxy/FSiO2@sND coatings showed a corrosion improvement efficiency of 138% at an optimum immersion time of 5 h, which was higher than the 96% improvement for epoxy/FSiO2 coating. Epoxy/FSiO2@sND intact coating showed much higher low-frequency impedance, i.e., 7.23 Ω·cm2, compared with epoxy/FSiO2 coating, i.e., 5.44 Ω·cm2, and neat epoxy coating, i.e., 5.71 Ω·cm2, after 22 weeks of immersion in salty solution. This result along with a detailed analysis of EIS data for intact coatings suggested that FSiO2@sND brought about strong barrier anticorrosive performance for epoxy coating. Such behavior was attributed to improved dispersion of nanohybrid in the epoxy matrix, enhanced cross-link density of the epoxy matrix, and improved coating/substrate adhesion caused by APTES and the carboxylic groups of ND.

Focus on podocytes: diabetic kidney disease and renal fibrosis - a global bibliometric analysis (2000-2024).

Diabetic kidney disease (DKD) is a common pathway to End-stage renal disease (ESRD). Podocytes are crucial due to their dual barrier functions in kidney diseases. Their role in renal fibrosis and DKD regulatory mechanisms is increasingly studied. However, bibliometric research in this field has not been explored. 1,250 publications from Jan. 1, 2000, to Feb. 16, 2024, were retrieved from the WoSCC database and analyzed by the Web of Science results analysis tool, VOSviewer, and CiteSpace. Our scrutiny reveals that authors Liu Youhua, Fogo Agnes B, and Zhao Yingyong have made substantial contributions to this domain. Notably, "Kidney International" has the highest volume of publications in this area. Furthermore, our analysis identifies ten co-citation clusters: DKD, IncRNA, reactive oxygen species, glomerulosclerosis, Poria cocos, glomerular diseases, fibroblasts, connective tissue growth factor, coagulation, and Wnt. Recent research accentuates keywords such as autophagy, TRPC6, ERS, epigenetics, and NLRP3 inflammasome as frequently occurring terms in this field. The prevailing research hotspot keywords include autophagy, biomarker, and exosomes. Through the utilization of bibliometric tools and knowledge graph analysis, we have undertaken a comprehensive review of the intricate nexus between podocytes in DKD and renal fibrosis. This study imparts valuable insights to scholars regarding the dynamic evolution of this association and delineates prospective research avenues in this pivotal realm.

Dual barrier system against xenomitochondrial contamination in mouse embryos

Heteroplasmic mammalian embryos between genetically distant species fail to develop to term, preventing transmission of xenomitochondrial DNA to progeny. However, there is no direct evidence indicating the mechanisms by which species specificity of the mitochondrial genome is ensured during mammalian development. Here, we have uncovered a two-step strategy underlying the prevention of xenomitochondrial DNA transmission in mouse embryos harboring bovine mitochondria (mtB-M embryos). First, mtB-M embryos showed metabolic disorder by transient increase of reactive oxygen species at the 4-cell stage, resulting in repressed development. Second, trophoblasts of mtB-M embryos led to implantation failure. Therefore, we tested cell aggregation with tetraploid embryos to compensate for the placentation of mtB-M embryos. The 14 mtB-M embryos harboring bovine mtDNAs developed to term at embryonic day 19.5. Taken together, our results show that contamination of bovine mtDNA is prohibited by embryonic lethality due to metabolic disruption and failure of placentation, suggesting these represent xenomitochondrial elimination mechanisms in mammalian embryos.

Dual oil-resistant membranes based on metal-polyphenol networks and NiFe layered double hydroxides for sustainable oil-in-water emulsion separation

In this study, NiFe layered double hydroxides (LDHs) are embedded in metal-polyphenol networks (MPNs) composed of tannic acid and Ti to build dual oil-resistant barriers on the substrate. The prepared membrane shows 99.9 % oil removal due to the synergistic effect of the first barrier based on LDHs and the second barrier based on MPNs. It achieves an average flux of 4174 L m−2 h−1 bar−1 in the cross-flow separation of oil-in-water emulsions containing surfactants, which is 3.9 times higher than that of the pristine PVDF. In addition, it can treat complex emulsions, removing 99.22 % of methylene blue, 92.47 % of tetracycline hydrochloride and and 89.65 % of Cr (VI) from the emulsion while removing oil. It also shows good separation performance for actual emulsified wastewater from industrial processes. This research provides a new approach to the design of oil–water separation materials to achieve high oil resistance and continuous separation.

Ultrasound Nanobubble Coupling Agent for Effective Noninvasive Deep-Layer Drug Delivery.

Conventional coupling agents (such as polyvinylpyrrolidone, methylcellulose, and polyurethane) are unable to efficiently transport drugs through the skin's dual barriers (the epidermal cuticle barrier and the basement membrane barrier between the epidermis and dermis) when exposed to ultrasound, hindering deep and noninvasive transdermal drug delivery. In this study, nanobubbles prepared by the double emulsification method and aminated hyaluronic acid are crosslinked with aldehyde-based hyaluronic acid by dynamic covalent bonding through the Schiff base reaction to produce an innovative ultrasound-nanobubble coupling agent. By amplifying the cavitation effect of ultrasound, drugs can be efficiently transferred through the double barrier of the skin and delivered to deep layers. In an in vitro model of isolated porcine skin, this agent achieves an effective penetration depth of 728µm with the parameters of ultrasound set at 2W, 650kHz, and 50% duty cycle for 20min. Consequently, drugs can be efficiently delivered to deeper layers noninvasively. In summary, this ultrasound nanobubble coupling agent efficiently achieves deep-layer drug delivery by amplifying the ultrasonic cavitation effect and penetrating the double barriers, heralding a new era for noninvasive drug delivery platforms and disease treatment.

Life cycle analysis of common landfill final cover systems focusing on carbon neutrality

Carbon emissions from landfill construction and management have become a global concern. Life cycle analysis (LCA) has been widely used to assess the environmental impacts of engineered infrastructures over their lifetimes. LCA has also been applied to landfill leachate and gas management, but rarely to landfill final cover systems. This paper reports the results of an LCA of the following landfill final cover systems: compacted clay cover, geomembrane cover, cover with capillary effects (CCBE), dual capillary barrier cover, three-layer landfill cover system using natural soils, three-layer cover using recycled concrete aggregate (RCA) and biochar-amended three-layer landfill cover system using RCA. The LCA assessment of landfill cover considers the cost, carbon emissions and carbon sequestration during the production, construction and operation phases. The effects of landfill cover on global warming, freshwater eutrophication, terrestrial ecotoxicity, freshwater ecotoxicity, marine ecotoxicity and fossil resource scarcity are also evaluated. In addition, the sensitivities of cost and carbon emission to the use of electric-powered machines and transportation distance are analysed. It is revealed that the three-layer cover system using RCA and biochar has the lowest unit cost and carbon emission of all of the covers, up to 88 % and 66 % lower, respectively, than those of the other six covers. In addition, this cover system has the highest carbon sequestration rate, with a value of 47.9 kg CO2/(y·m2), four times higher than that of the compacted clay cover. Finally, this sustainable cover mitigates global warming and reduces adverse environmental impacts by up to 82 %. Therefore, the biochar amended three-layer cover system using RCA without geomembrane offers the greatest economic benefits, performs effectively in terms of the pursuit of carbon neutrality and promotes sustainable development.

Fast zinc-ion storage enabled by hydrophobic alkyl chains via reducing dual diffusion barriers

Vanadium-based aqueous zinc-ion batteries (AZIBs) represent a highly promising solution for large-scale energy storage applications. For fast zinc-ion storage within the V2O5 cathode and mitigating its structural degradation, hydrophobic alkyl chains are pre-intercalated into V2O5. In particular, the synthesized tetraethylammonium pre-intercalated V2O5 (TEAVO) delivers a remarkable capacity of 470.9 mA h g–1 a 0.2 A g–1, especially excellent rate capability of 307.8 mA h g−1 at 10 A g–1 over 5,000 cycles (98.3 % capacity retention). Thorough investigations elucidate the multiple roles of the alkyl chains, including the inhibition of H2O insertion, facilitation of Zn2+ desolvation, and suppression of vanadium dissolution fundamentally. The combination of ex/in-situ characterizations and density functional theory (DFT) calculations has also unraveled the dual roles of the alkyl chains in reducing Zn2+ diffusion barriers. Notably, the diffusion barriers governing the entire Zn2+ insertion process have been determined for the first time at least for TEAVO. This pioneering work presents novel insights into the organic pre-intercalation, and sheds light on the advancement of AZIBs technology.

Self-perception of dual career barriers and athletic identity in student-athletes with disabilities according to disability type and level of professionalization

The objective of this study was to analyze the perceived barriers to dual career success and athletic identity of student-athletes according to disability type and level of professionalization. The final sample consisted of 203 student-athletes with disabilities from five European countries. The questionnaires used were ESTPORT, EBBS and AIMS. Depending on disability type, it was found that student-athletes with hearing and physical impairment showed the highest difficulty in reconciling sports and studies (p = 0.001); that student-athletes with a hearing impairment showed the highest score in the barrier ‘the cost of education is high’ (p = 0.023); that student-athletes with a physical impairment had the highest scores in the barrier ‘Exercise tires me’ (p = 0.013); that student-athletes with cerebral palsy showed the highest scores in the barrier ‘I do not have enough university/educational institution support’ (p = 0.014) and ‘Exercise facilities do not have convenient timetables for me’ (p = 0.001). Depending on sports professionalization level, semi-professional student-athletes showed the highest values in the barrier ‘the university/educational institution is far from my training center’ (p = 0.040); while professional student-athletes had the highest score in the barrier ‘exercise takes too much time from family responsibilities’ (p = 0.034). In most of the variables related to identity as athletes, professional student-athletes showed the highest values, followed by semi-professional athletes (p = 0.043- < 0.001). In conclusion, the self-perception of barriers is quite relevant, with differences arising from disability type and level of professionalization, whereas the identity as an athlete is only different according to the level of professionalization.

Contention en gériatrie : le retard de la France

Passive physical restraint methods in geriatrics were defined at the start of this century, accompanied by recommendations relating to their use and more recently by legislation. Despite the frequency of these measures of restraint, there are few French publications on this subject. It seems that this practice varies according to the geriatric establishments and prevails in hospital more than in nursing home. The most widespread method is the dual barrier on the bed, as well as in hospital than in nursing home. To this should be added restraint provided by the premises themselves, intended to secure access to a facility, found in 90% of residences for the dependent elderly, and also medication. Passive physical restraint, mainly implemented to prevent falls, has however clearly shown its deleterious effects, particularly in the USA where it is thought to be responsible for 1/1000 deaths in nursing homes, although when it is absent there appears to be no increased risk of falls. Medication-based restraint is more readily used to sedate in case of disruptive behaviors (agitation, aggressiveness) although no clear data is available to date. Restraint provided by the premises themselves, used preventively in case of wandering and straying, is nevertheless a deprivation of freedom, and seems to concern the majority of geriatric facilities today. In the absence of legislation to regulate more clearly these practices, the present authors discuss the need for ethical reflection before the implementation of measures of restraint, whatever their nature, and they propose certain ideas on possible methods for passive physical restraint: raising awareness among caregivers and family members who often call for these measures, the existence of alternative measures, and the delaying of implementation as long as possible and/or sequentially.