Hierarchical Emulsion Structure and Functionality Regulated by Coexisting Bicontinuous Microemulsion and Liquid Crystal Domains.

Since microemulsions are usually low viscosity fluids, enhanced rheological properties while maintaining their structure-derived functionality have long been desired from an industrial application point of view. However, for instance, it is practically difficult to thicken bicontinuous microemulsions (BCMEs) without perturbing their alternating domain structure or to emulsify oils using BCME having ultralow interfacial tension as an external phase. In this study, a methodology called a BCLC emulsification technique has been constructed to obtain oil-in-water emulsions stabilized by coexisting BCME and liquid crystal (LC) phases. The produced emulsions based on polyglyceryl-10 diisostearate, polyglyceryl-6 dicaprate, cetyl ethylhexanoate, and water are structurally scrutinized by means of small- and wide-angle X-ray scattering (SWAXS), freeze fracture transmission electron microscopy (FF-TEM), and scanning electron assisted dielectric microscopy (SE-ADM). The data provide experimental evidence that this methodology enables one to control the bending elasticity of the interfacial membranes and consequent long-range order of the BCME domains. Moreover, closely correlated with the interfacial membrane properties, submicrometer-sized fine oil droplets are supported by the LC networks and agglomerated into spongy or network-like phase-separation patterns. The resulting nonfluidic, jelly emulsions are particularly useful in cosmetics because of combined BCME-derived high cleansing performance and excellent usability owing to the enhanced viscosity. The thickening mechanisms are essentially different from those of common lamellar-gel-stabilized oil-in-water emulsions, which utilize crystalline lamellar gel networks as oil droplet stabilizers.

Direct observation of the effects of chemical fixation in MNT-1 cells: A SE-ADM and Raman study.

Aldehydes fixation was accidentally discovered in the early 20th century and soon became a widely adopted practice in the histological field, due to an excellent staining enhancement in tissues imaging. However, the fixation process itself entails cell proteins denaturation and crosslinking. The possible presence of artifacts, that depends on the specific system under observation, must therefore be considered to avoid data misinterpretation. This contribution takes advantage of scanning electron assisted-dielectric microscopy (SE-ADM) and Raman 2D imaging to reveal the possible presence and the nature of artifacts in unstained, and paraformldehyde, PFA, fixed MNT-1 cells. The high resolution of the innovative SE-ADM technique allowed the identification of globular protein clusters in the cell cytoplasm, formed after protein denaturation and crosslinking. Concurrently, SE-ADM images showed a preferential melanosome adsorption on the cluster's outer surface. The micron-sized aggregates were discernible in Raman 2D images, as the melanosomes signal, extracted through 2D principal component analysis, unequivocally mapped their location and distribution within the cells, appearing randomly distributed in the cytoplasm. Protein clusters were not observed in living MNT-1 cells. In this case, mature melanosomes accumulate preferentially at the cell periphery and are more closely packed than in fixed cells. Our results show that, although PFA does not affect the melanin structure, it disrupts melanosome distribution within the cells. Proteins secondary structure, conversely, is partially lost, as shown by the Raman signals related to α-helix, ß-sheets, and specific amino acids that significantly decrease after the PFA treatment.

Enhanced Removal of Photoresist Films through Swelling and Dewetting Using Pluronic Surfactants.

Organic photoresist coatings, primarily composed of resins, are commonly used in the electronics industry to protect inorganic underlayers. Conventional photoresist strippers, such as amine-type agents, have shown high removal performance but led to environmental impact and substrate corrosiveness. Therefore, this trade-off must be addressed. In this study, we characterized the removal mechanism of a photoresist film using a nonionic triblock Pluronic surfactant [poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)] in a ternary mixture of ethylene carbonate (EC), propylene carbonate (PC), and water. In particular, the removal dynamics determined by using a quartz crystal microbalance with dissipation monitoring was compared with those determined by performing confocal laser scanning microscopy and visual observation to analyze the morphology, adsorption mass, and viscoelasticity of the photoresist film. In the absence of the Pluronic surfactant, the photoresist film in the ternary solvent exhibited a three-step process: (i) film swelling caused by the penetration of a good solvent (EC and PC), (ii) formation of photoresist particles through dewetting, and (iii) particle aggregation on the substrate. This result was correlated to the Hansen solubility parameters. The addition of the Pluronic surfactant not only prevented photoresist aggregation in the third step but also promoted desorption from the substrate. This effect was dependent on the concentration of the Pluronic surfactant, which influenced diffusion to the interface between the photoresist and the bulk solution. Finally, we proposed a novel photoresist stripping mechanism based on the synergy between dewetting driven by an EC/PC-to-water mixture and adsorption by the Pluronic surfactant.

Anti-adsorption Mechanism of Photoresist by Pluronic Surfactants: An Insight into Their Adsorbed Structure.

Photoresist stripping is the final step in the photolithography process that forms fine patterns for electronic devices. Recently, a mixture of ethylene carbonate (EC) and propylene carbonate (PC) has attracted attention as a new stripper based on its eco-friendliness and anti-corrosiveness. However, the EC/PC mixture causes re-adsorption of the photoresist during a process of subsequent water rinsing. In this study, we characterized the adsorption/desorption of the photoresist and a triblock Pluronic surfactant [poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)] as a blocking agent on an indium tin oxide (ITO) substrate. In addition, we evaluated the dispersion of photoresist particles. The photoresist polymer formed a thin and rigid adsorption layer on an ITO substrate in the EC/PC mixture. When water was injected into the EC/PC mixture and the photoresist solutions, the photoresist polymer aggregated and was then deposited on the substrate. In contrast, the addition of Pluronic surfactant F-68 (PEO79PPO30PEO79) into the EC/PC mixture remarkably decreased the residual amount of the photoresist on the ITO after water injection. This variation was attributed to the PEO blocks of F-68 extended to the solution phase, whereas the PPO blocks of F-68 functioned as anchors for adsorption onto the photoresist. Therefore, the F-68-adsorbed layer prevented interaction between the photoresist particles or the photoresist and the ITO surface, which provides potential for future applications as new stripping agents with high removal performance.

Structural analysis of melanosomes in living mammalian cells using scanning electron-assisted dielectric microscopy with deep neural network.

Melanins are the main pigments found in mammals. Their synthesis and transfer to keratinocytes have been widely investigated for many years. However, analysis has been mainly carried out using fixed rather than live cells. In this study, we have analysed the melanosomes in living mammalian cells using newly developed scanning electron-assisted dielectric microscopy (SE-ADM). The melanosomes in human melanoma MNT-1 cells were observed as clear black particles in SE-ADM. The main structure of melanosomes was toroidal while that of normal melanocytes was ellipsoidal. In tyrosinase knockout MNT-1 cells, not only the black particles in the SE-ADM images but also the Raman shift of melanin peaks completely disappeared suggesting that the black particles were really melanosomes. We developed a deep neural network (DNN) system to automatically detect melanosomes in cells and analysed their diameter and roundness. In terms of melanosome morphology, the diameter of melanosomes in melanoma cells did not change while that in normal melanocytes increased during culture. The established DNN analysis system with SE-ADM can be used for other particles, e.g. exosomes, lysosomes, and other biological particles.

Effect of polyols on membrane structures of liposomes: A study using small-angle X-ray scattering data and generalized indirect Fourier transformation.

This study aimed to evaluate the membrane structure of distearoylphosphatidylcholine (DSPC) liposomes dispersed in water containing various types of polyols with low molecular weight such as glycerin (Gly), 1,3-butandiol (BG), and propylene glycol (PG). To clarify the detailed membrane structure, generalized indirect Fourier transformation (GIFT) analysis, which provides information about the bilayer spacing, bilayer thickness, number of lamellar layers, and membrane flexibility, was applied to small-angle X-ray scattering (SAXS) data of the present system. The GIFT results showed that the bilayer thickness of the DSPC liposomes followed the order Gly>>BG>PG. In addition, the membrane flexibility estimated by the Caille parameter was in the order Gly>>BG>PG; this result was supported by the gel-liquid crystal phase transition temperature (Tc) obtained by differential scanning calorimetry (DSC). These results, together with the Raman spectra, suggest that BG and PG incorporated into the bilayers of DSPC liposomes result in the formation of an interdigitated lamellar structure.

Nanostructured fluids for polymeric coatings removal: Surfactants affect the polymer glass transition temperature.

HYPOTHESIS: Nanostructured fluids (NSFs) based on water, organic solvents and surfactants are a valid alternative to the use of neat unconfined organic solvents for polymer coatings removal in art conservation. The physico-chemical processes underpinning their cleaning effectiveness in terms of swelling/dewetting of polymer films were identified as key in this context. The role of surfactants on polymers' dewetting was considered to be mainly restricted to the lowering of interfacial tensions. However, recent experiments evidenced that surfactants have an important role in swelling polymer films. EXPERIMENTS: Five different amphiphiles were selected, namely: sodium dodecylsulfate, dimethyldodecyl amine oxide, hexaoxyethylene decyl ether (C9-11E6), pentadecaoxyethylene dodecyl ether (C12E15), and methyoxypentadecaoxyethylene dodecanoate (C11COE15CH3). They were combined with a carefully selected organic solvents' mixture (1-butanol/butanone/dimethyl carbonate) to formulate new NSFs, differing for the surfactant only, and used to perform cleaning tests on surfaces coated with Paraloid B72® and Primal AC33®. Here for the first time, polymer swelling induced by surfactants was quantified and correlated with the glass transition temperature of the two polymers by differential scanning calorimetry, before and after the exposure to the fluids. Confocal laser scanning microscopy and small-angle X-ray scattering provided additional insights on the interaction mechanism. FINDINGS: Nonionics were proven more efficient than zwitterionic/ionic amphiphiles in the polymer swelling, and, overall, methyoxy pentadecaoxyethylene dodecanoate resulted the most effective among the selected surfactants. A direct relation between the effect of surfactants on the polymers' glass transition temperature and cleaning capacity was established. This finding, fundamental to understand the interaction mechanism between NSFs and polymer coatings or paint layers, is key to achieve a selective, effective and complete removal of polymer coatings, as recently shown in the removal of vandalism and over-paintings from street art.

Contrast Variation Small-Angle Neutron Scattering Study of Solubilization of Perfumes in Cationic Surfactant Micelles.

Perfume solubilization is an important process in the production of commercial products such as beverages, foods, and cosmetics. In the present study, small-angle neutron scattering (SANS) experiments were performed to investigate the solubilization behavior of perfumes in cetyltrimethylammonium bromide (CTAB) micelles. The solubilization of linalool (LL) and l-menthol (MT), which are relatively hydrophilic perfumes, did not change the size of the CTAB micelles although the perfumes were incorporated in the micelles, as indicated by a decrease in scattering length density. On the other hand, the solubilization of d-limonene (LN), a hydrophobic perfume, led to the swelling of CTAB micelles. An internal contrast variation SANS study was performed by the deuteration of CTAB molecules to directly observe the perfumes in the micelles. The radius of d-CTAB micelles solubilizing LL or MT corresponds to that of h-CTAB, which indicates that these perfumes are accommodated in the palisade layers of the micelles and are homogeneously distributed in the micelles. On the other hand, LN formed small droplets, as indicated by the SANS profile, which implies the solubilization of LN molecules in the core of the CTAB micelles. We found that the relatively hydrophilic perfumes (LL and MT) show less impact on the sizes of the cationic micelles in comparison to nonionic micelles. Thus, the internal contrast variation method of SANS allowed the direct observation of the solubilization sites of perfumes with different hydrophilicity-hydrophobicity balances. This method is a powerful tool to determine the solubilization states that affect the solubilization capacity, volatilization, or release speed of perfumes.

Amino Acids and Their N-Acetylated Derivatives Maintain the Skin's Barrier Function.

The hydrocarbon-chain packing structure of intercellular lipids in the stratum corneum (SC) is critical to the skin's barrier function. We previously found that formation of V-shaped ceramide reduces the barrier function of skin. There are few agents, apart from ceramides and fatty acids that can improve the orthorhombic packing (Orth) ratio of the intercellular lipid packing structure. In this study, we investigated agents that directly increase the Orth ratio. We selected an intercellular lipid model consisting of ceramide, cholesterol, and palmitic acid and performed differential scanning calorimetry. We focused on natural moisturizing factor components in the SC, and therefore investigated amino acids and their derivatives. The results of our intercellular lipid model-based study indicate that N-acetyl-L-hydroxyproline (AHYP), remarkably, maintains the lamellar structure. We verified the effect of AHYP on the lamellar structure and hydrocarbon chain packing structure of intercellular lipids using time-resolved X-ray diffraction measurements of human SC. We also determined the direct physicochemical effects of AHYP on the Orth ratio of the hydrocarbon-chain packing structure. Hence, the results of our human SC study suggest that AHYP preserves skin barrier function by maintaining the hydrocarbon-chain packing structure of intercellular lipids via electrostatic repulsion. These findings will facilitate the development of skincare formulation that can maintain the skin's barrier function.

Effect of Anionic Amphiphiles on the Morphology of Hexagonal Plate-like ZnO Particles.

Zinc oxide (ZnO) particles were synthesized in the presence of anionic surfactants (ASs). The effect of ASs on the morphology of the ZnO particles was investigated by using ASs with various alkyl chain lengths and changing the molar ratio of AS/ZnSO4. Hexagonal plate-like ZnO particles were formed in the presence of ASs. Adsorption of the AS on the c face of the ZnO crystals inhibited (promoted) crystal growth along the c-axis (ab-axis) direction. Increasing the molar ratio of AS/ZnSO4 decreased the particle thickness, owing to the resulting increase in the coverage of the c face with AS. The particle diameter of the hexagonal plate-like ZnO particles (the diagonal length of the hexagonal plate) increased with increasing alkyl chain length of AS as a result of the van der Waals interactions between the alkyl chains. The data indicate that the particle diameter and thickness can be controlled by fine-tuning the van der Waals interactions between the alkyl chains and the coverage of the c face of the ZnO particles with AS.

Selective removal of over-paintings from "Street Art" using an environmentally friendly nanostructured fluid loaded in highly retentive hydrogels.

HYPOTHESIS: The removal of over-paintings or graffiti is a priority for conservators and restorers. This operation is complex, especially when over-paintings lay on painted surfaces that must be preserved, as in the case of vandalism on street art, where the layers are usually chemically similar. Traditional methodologies often do not provide satisfactory results and pose health and eco-compatibility concerns. An alternative methodological approach based on an environmentally friendly nanostructured fluid loaded in a retentive hydrogel is here proposed. EXPERIMENTS: Six paints (based on vinyl, acrylic and alkyd polymers) were selected and studied by means of attenuated total reflection - Fourier transform infrared spectroscopy. The phase behavior of four alkyl carbonates (green, low-toxicity organic solvents) and a biodegradable nonionic surfactant in water was investigated with Small angle X-ray scattering (SAXS) in order to formulate a novel nanostructured cleaning system. The developed system, which also includes 2-butanol and an alkyl glycoside hydrotrope, was loaded in highly retentive hydrogels and tested in the selective removal of over-paintings from laboratory mockups and from real pieces of street art. FINDINGS: The selective and controlled removal of modern paints from substrates with similar chemical composition has been achieved using a specifically tailored NSF embedded in a retentive hydrogel. The proposed methodology and cleaning system provided excellent cleaning results, representing a new tool for the conservation of contemporary and, in particular, street art.

Phase Separation in Lipid Lamellae Result from Ceramide Conformations and Lateral Packing Structure.

Intercellular lipids in the stratum corneum protect the living body from invasion by allergens and pathogens, and also suppresses water evaporation within the body. It is important to understand how differences in the microstructure of intercellular lipids arise. This microstructure is affected by lipid composition. Studies using intercellular lipid models have reported the formation of two phases with different short lamellar periodicities. However, the details of the packing structure characteristics of the two phases observed in these intercellular lipid models are unclear. Our previous report revealed that different short periodicity phases coexist in the N-(α-hydroxyoctadecanoyl)-dihydrosphingosine (CER[ADS]), cholesterol (CHOL), and palmitic acid (PA) complex model. In this study, the characteristics of the packing structure of two phases with different short lamellar periodicities, which were observed in the intercellular lipid model (CER[ADS]/CHOL/PA) that we used previously, were adjusted for models with different lipid compositions. The characteristics of the packed and lamellar structures have been determined by temperature-scanning small-angle X-ray scattering and wide-angle X-ray diffraction measurements simultaneously. These differences in lamellar structure were thought to be caused by differences in ceramides (CER) conformation between the hairpin and the V-shape type. The lamellar structure of the V-shaped CER conformation has a low orthorhombic ratio. The above results suggest that an increase in the ratio of CER with the V-shaped structure causes the lamellar structure to have low orthorhombic ratio, thereby contributing to a decrease in the bilayer's barrier function.

Preparation of Hexagonal Plate-like ZnO Single-crystal Particles in the Presence of Anionic Amphiphiles.

In this study, we synthesized ZnO particles using anionic amphiphiles as an additive. While the single-crystal particles prepared in the absence of such amphiphiles had a hexagonal rod-like shape, those fabricated using anionic amphiphilic molecules had a hexagonal plate-like shape. The anionic amphiphiles inhibited crystal growth in the c-axis direction of ZnO. This demonstrated that the anionic surfactants served as crystal-growth-directing agents, controlling the shape of the ZnO particles.

Nonionic Surfactants for the Cleaning of Works of Art: Insights on Acrylic Polymer Films Dewetting and Artificial Soil Removal.

The use of nanostructured fluids (NSFs), that is, micellar solutions and microemulsions, in art conservation is often associated with cleaning purposes as the removal of polymeric coatings and/or soil from artistic surfaces. In both cases, the use of NSFs grants significant improvements over the use of traditional cleaning techniques that employ neat unconfined organic solvents, water, or aqueous solutions. The study of the nature and properties of surfactants present in NSF formulations is important to boost the effectiveness of these systems in applicative contexts and in the search of innovative and highly performing amphiphiles. This work reports on the methoxy-pentadeca(oxyethylene) dodecanoate (MPD) surfactant in two different NSFs, whose utilization in conservation of cultural heritage is new. Its effectiveness is compared to the conventional nonionic amphiphiles used in conservation practice, as pentadeca(oxyethylene) dodecyl ether, for the cleaning of poly(ethyl methacrylate/methyl acrylate) 70:30, p(EMA/MA), and artificially soiled surfaces. The mechanism, through which NSFs interact with polymeric coatings or soiled surfaces, was investigated by confocal laser scanning microscopy, fluorescence correlation spectroscopy, photographic observation, contact angle, surface tension measurements, and small-angle X-ray scattering. The results highlighted the superior MPD's performance, both in inducing polymer removal and in detaching the soil from coated surfaces. At the microscale, the cleaning involves dewetting-like processes, where the polymer or the soil oily phase is detached from the surface and coalesce into separated droplets. This can be accounted by considering the different surface tensions and the different adsorption mechanisms of MPD with respect to ordinary nonionic surfactants (likely due to the methyl capping of the polar head chain and to the presence of the ester group between the hydrophilic and hydrophobic parts of the MPD surfactant molecule), showing how a tiny change in the surfactant architecture can lead to important differences in the cleaning capacity. Overall, this paper provides a detailed description of the mechanism and the kinetics involved in the NSFs cleaning process, opening new perspectives on simple formulations that are able to target at a specific substance to be removed. This is of utmost importance in the conservation of irreplaceable works of art.

Osteoblastic lysosome plays a central role in mineralization.

Mineralization is the most fundamental process in vertebrates. It is predominantly mediated by osteoblasts, which secrete mineral precursors, most likely through matrix vesicles (MVs). These vesicular structures are calcium and phosphate rich and contain organic material such as acidic proteins. However, it remains largely unknown how intracellular MVs are transported and secreted. Here, we use scanning electron-assisted dielectric microscopy and super-resolution microscopy for assessing live osteoblasts in mineralizing conditions at a nanolevel resolution. We found that the calcium-containing vesicles were multivesicular bodies containing MVs. They were transported via lysosome and secreted by exocytosis. Thus, we present proof that the lysosome transports amorphous calcium phosphate within mineralizing osteoblasts.

Leg Muscle Strength After Lateral Interbody Fusion Surgery Recovers Over Time After Temporary Muscle Weakness.

STUDY DESIGN: Case-control study. OBJECTIVE: The objective of this study was to reveal the changes of leg muscle strength after lateral interbody fusion (LIF). SUMMARY OF BACKGROUND DATA: Muscle trauma and damage to intermuscular nerves due to dissection of the psoas are recognized perioperative complications of LIF. Although reduced leg strength is temporary in many cases, the underlying changes have not been studied in detail. METHODS: Leg muscle strength was measured quantitatively before LIF surgery and 1 week, 2 weeks, 3 weeks, 4 weeks, 8 weeks, and 12 weeks after surgery (n=38). Reduced muscle strength was defined as <80% of the preoperative measurement. The psoas position (PP%) was calculated from axial T2-weighted magnetic resonance images and compared with the degree of psoas and quadriceps muscle strength reduction at 1 week after surgery on the approach side. Twenty cases that underwent a posterior lumbar approach (posterior group) acted as controls. RESULTS: The proportion of patients with reduced psoas muscle strength 1 week after LIF was 60.5% on the approach side and 39.5% on the healthy side, versus 30.0% in the posterior group. The corresponding results for the quadriceps were 34.2%, 39.5%, and 25.0%, respectively. All cases had strength improvement on the approach side by 12 weeks postsurgery in the psoas and by 4 weeks postsurgery for the quadriceps. Psoas muscle strength and quadriceps strength at 1 week after surgery were correlated (ρ=0.57, P<0.001). There was a low inverse correlation between PP% and quadriceps strength at 1 week (ρ=-0.31, P<0.001). CONCLUSIONS: Muscle strength declined in both the psoas and quadriceps muscle groups after LIF; however, the effect was temporary and strength recovered over time. Reduced postoperative quadriceps muscle strength may relate the position of the psoas muscle via increased irritation of the lumbar plexus during the splitting maneuver.

Ion fluctuations and intermembrane interactions in the aqueous dispersions of a dialkylchain cationic surfactant studied using dielectric relaxation spectroscopy and small- and wide-angle X-ray scattering.

A dialkylchain cationic surfactant forms the so-called α-gel in water showing virtually no fluidity, which is transformed into a highly fluidic dispersion upon addition of a small amount of salt. This intriguing phenomenon is utilized in household industries. However, the underlying mechanisms remain unclear. Here, we use dielectric relaxation spectroscopy (DRS) and simultaneous small- and wide-angle X-ray scattering (SWAXS) to shed light on this issue. We find that an excess amount of CaCl2 induces an α-gel-to-multi-lamellar vesicle (MLV) transition accompanied by a marked increase of the reservoir volume fraction. This resembles an unbound lamellar-to-bound lamellar transition that cannot be explained without invoking a weak long-ranged electrostatic attraction. The DRS data provide evidence that the counterions fluctuate both vertically and laterally at the interface, whose relaxation amplitudes sharply depend on a percolating state of an aqueous phase. The strikingly small bulk-water amplitude is likely to reflect depolarizing electric fields induced by the MLV architecture, along with genuine hydration effects. The modified Caillé approach to the SAXS intensities reveals sensitive salt-concentration dependent membrane-membrane interactions. The least undulating membranes are formed at a salt concentration of ca. 10 mmol L-1. Above 25 mmol L-1, where small surface separation (<2.5 nm) is attained, far more undulating membranes than those predicted by the Helfrich interaction are produced. This suggests that the hydration forces, generally believed to induce strong short-range repulsion, do not suppress the membrane undulation fluctuations.

Facet Joint Osteoarthritis Affects Spinal Segmental Motion in Degenerative Spondylolisthesis.

STUDY DESIGN: This is a retrospective clinical case series (case-control study). OBJECTIVE: To clarify the influence of facet joint osteoarthritis (FJOA) on the pathology of degenerative spondylolisthesis (DS) using in vivo 3-dimensional image analysis. SUMMARY OF BACKGROUND DATA: There are no radical treatments to prevent progression of DS in patients with lumbar spinal canal stenosis associated with DS. Therefore, an effective treatment method based on the pathology of DS should be developed. PATIENTS AND METHODS: In total, 50 patients with lumbar spinal canal stenosis involving L4/5 who underwent dynamic computed tomography were divided into 2 groups: with DS [spondylolisthesis (Sp) group; 12 male, 14 female; mean age, 74 y]; and without DS (non-Sp group; 15 male, 9 female; mean age, 70 y). Degeneration of the intervertebral disk and FJOA at L4/5 were evaluated using magnetic resonance imaging. Disk and intervertebral foramen heights, the distance between the craniocaudal edges of the facet joint, and the interspinous distance were measured on dynamic computed tomographic images. Also, in vivo 3-dimensional segmental motion was evaluated using the volume merge method. RESULTS: There were no significant differences in degenerative findings for the intervertebral disk; however, progressive FJOA was detected in the Sp group. Dynamic changes in the distance between the craniocaudal edges of the facet joints were significantly larger in the Sp group. CONCLUSIONS: In this study, progressive FJOA and larger segmental motion in the distance between the craniocaudal edges of the facet joints were found in the Sp group. We clarified for the first time that DS involves ligament laxity due to FJOA that affects spinal segmental motion in vivo. We consider that a treatment method based on FJOA would be useful for treating patients with DS. LEVEL OF EVIDENCE: Level IV.

Small Angle X-ray Scattering and Electron Spin Resonance Spectroscopy Study on Fragrance Infused Cationic Vesicles Modeling Scent-Releasing Fabric Softeners.

Industrially relevant systems for household and personal-care products often involve a large number of components. Such multiple component formulations are indispensable and effective for functionalization of the products, but may simultaneously provide more complex structural features compared to those in ideal systems comprising a smaller number of highly pure substances. Using cryogenic transmission electron microscopy (cryo-TEM), small angle X-ray scattering (SAXS), and electron spin resonance (ESR) spectroscopy, we have investigated effects of fragrance-incorporation into cationic vesicles on their bilayer structures and membrane-membrane interactions. Cationic vesicles were prepared from TEQ surfactant, whose major component was di(alkyl fatty ester) quaternary ammonium methosulfate, and fragrance components, l-menthol, linalool, and d-limonene, were infused into the vesicle membranes to model scent-releasing fabric softeners. The cryo-TEM images confirm formation of multilamellar vesicles (MLVs). Generalized indirect Fourier transformation (GIFT) analysis of the SAXS intensities based on the modified Caillé structure factor model reveals that incorporation of a more hydrophobic fragrance component leads to a more pronounced increase of the surface separation (water layer thickness). Furthermore, the fragrance-infused systems show longer-range order of the bilayer correlations and enhanced undulation fluctuation of the membranes than those in the TEQ alone system. The spin-label ESR results indicate different restricted molecular motions in the TEQ bilayers depending on the labeled position and their marked changes upon addition of the fragrance components, suggesting different mixing schemes and solubilization positions of the fragrance molecules in the TEQ bilayers. The present data have demonstrated how the infused fragrance molecules having different hydrophobicity and molecular architectures into the cationic vesicles affect the membrane structures and the intermembrane interactions, which may provide useful information for precisely controlling a fragrance-releasing property.

Effect of three-dimensional rotational deformity correction in surgery for adult degenerative scoliosis using lumbar lateral interbody fusion and posterior pedicle screw fixation.

INTRODUCTION: Corrective surgery for adult degenerative scoliosis using lateral interbody fusion (LIF) and additional posterior fixation is an efficient procedure. However, it is unclear how this procedure affects rotational deformity correction. Therefore, the goal of the present study was to use three-dimensional (3D) images, taken during surgery, to investigate rotational deformity correction in the treatment of adult degenerative scoliosis using LIF and posterior fixation using a pedicle screw system. METHODS: The subjects were 12 females who were treated using LIF and posterior fixation for adult degenerative scoliosis. The patients had a mean age of 72 (65-76) years. 3D images were acquired before surgery, after LIF, and after additional posterior fixation. Rotational angles of the upper vertebra with respect to the lower vertebra of each fixed segment were measured in 3 planes. Correction factors for rotational deformity were investigated after LIF and additional posterior fixation. RESULTS: There were significant improvements in radiographical parameters for global spinal balance. The correction angles per segment were 4.7° for lateral bending, 6.9° for lordosis, and 4.5° for axial rotation. LIF was responsible for correction of four-fifths of lateral bending and axial rotation, and two-thirds of lordotic changes. CONCLUSIONS: Lateral bending, axial rotational deformities, and lordosis were primarily corrected by LIF. Further lordosis correction was achieved using additional posterior fixation. These results indicate that corrective surgery for adult degenerative scoliosis using these procedures is effective for rotational deformity correction and leads to an ideal global spinal alignment.