Adsorption-Induced Dye Stability of Cationic Dyes on Clay Nanosheets

Rhodamine 6G (R6G) was adsorbed on smectite clays, a natural montmorillonite, a synthetic saponite, and synthetic hectorites, and the decolorization of the dyes upon visible light irradiation was examined for aqueous suspensions and cast films. Excellent dye stability was achieved when a natural montmorillonite was used. Apart from R6G, better photostability was also achieved when the tris(2,2'-bipyridine)ruthenium(II) complex was adsorbed on a natural montmorillonite. The excited state of the dye was quenched efficiently by the impurities in the natural montmorillonite. From the relationship between the excited-state quenching (as derived from photoluminescence quantum efficiency and photoluminescence intensity) and the decolorization rate constant, the quenching of the excited state of the dye adsorbed on the natural montmorillonite was proposed as the important mechanism for the stabilization of dyes upon photoirradiation.

Unsaturated Mn(II)-Centered [Mn(BDC)] n Metal-Organic Framework with Strong Water Binding Ability and Its Potential for Dehydration of an Ethanol/Water Mixture

An unsaturated Mn(II)-centered metal-organic framework was synthesized. The presence of an unsaturated Mn(II) center, together with a guest-responsive structural changing feature, plays a crucial role for strong binding with water, leading to its potential application for water/ethanol separation. In addition, the present framework is thermally stable up to 400 °C, which is beneficial for the regeneration process after adsorption.

Layered Silicates as a Possible Drug Carrier

The potential of layered silicates as drug carrier is overviewed. Due to their large surface area and expandable interlayer space to accommodate drug molecules, layered silicates have a potential as carrier of various molecules. In addition to the electrostatic interactions between negatively charged layered silicates and positively charged drug molecules, the organic modification of the surface of layered silicates has been applied to accommodate a variety of drug molecules not only cationic ones. The in vitro release experiment of the accommodated drug molecules has been reported under the acidic conditions. In order to discuss the future direction of layered silicates as drug carrier, materials' variation of layered silicates and their modification, and the reported stimuli-responsive hybrids based on layered silicates were introduced.

The IL-13/periostin/IL-24 pathway causes epidermal barrier dysfunction in allergic skin inflammation

BACKGROUND

Barrier dysfunction is an important feature of atopic dermatitis (AD) in which IL-4 and IL-13, signature type 2 cytokines, are involved. Periostin, a matricellular protein induced by IL-4 or IL-13, plays a crucial role in the onset of allergic skin inflammation, including barrier dysfunction. However, it remains elusive how periostin causes barrier dysfunction downstream of the IL-13 signal.

METHODS

We systematically identified periostin-dependent expression profile using DNA microarrays. We then investigated whether IL-24 downregulates filaggrin expression downstream of the IL-13 signals and whether IL-13-induced IL-24 expression and IL-24-induced downregulation of filaggrin expression are dependent on the JAK/STAT pathway. To build on the significance of in vitro findings, we investigated expression of IL-24 and activation of STAT3 in mite-treated mice and in AD patients.

RESULTS

We identified IL-24 as an IL-13-induced molecule in a periostin-dependent manner. Keratinocytes are the main IL-24-producing tissue-resident cells stimulated by IL-13 in a periostin-dependent manner via STAT6. IL-24 significantly downregulated filaggrin expression via STAT3, contributing to barrier dysfunction downstream of the IL-13/periostin pathway. Wild-type mite-treated mice showed significantly enhanced expression of IL-24 and activation of STAT3 in the epidermis, which disappeared in both STAT6-deficient and periostin-deficient mice, suggesting that these events are downstream of both STAT6 and periostin. Moreover, IL-24 expression was enhanced in the epidermis of skin tissues taken from AD patients.

CONCLUSIONS

The IL-13/periostin pathway induces IL-24 production in keratinocytes, playing an important role in barrier dysfunction in AD.

Immune-mediated acquired lecithin-cholesterol acyltransferase deficiency: A case report and literature review

BACKGROUND

Recessive inherited disorder lecithin-cholesterol acyltransferase (LCAT) deficiency causes severe hypocholesterolemia and nephrotic syndrome. Characteristic lipoprotein subfractions have been observed in familial LCAT deficiency (FLD) with renal damage.

OBJECTIVE

We described a case of acquired LCAT deficiencies with literature review.

METHODS

The lipoprotein profiles examined by gel permeation-high-performance liquid chromatography (GP-HPLC) and native 2-dimensional electrophoresis before and after prednisolone (PSL) treatment.

RESULTS

Here we describe the case of a 67-year-old man with severely low levels of cholesterol. The serum LCAT activity was undetectable, and autoantibodies against it were detected. The patient developed nephrotic syndrome at the age of 70 years. Renal biopsy revealed not only membranous glomerulonephritis but also lesions similar to those seen in FLD. We initiated PSL treatment, which resulted in remission of the nephrotic syndrome. In GP-HPLC analysis, lipoprotein profile was similar to that of FLD although lipoprotein X level was low. Acquired LCAT deficiencies are extremely rare with only 7 known cases including ours. Patients with undetectable LCAT activity levels develop nephrotic syndrome that requires PSL treatment; cases whose LCAT activity levels can be determined may also develop nephrotic syndrome, but spontaneously recover.

CONCLUSION

Lipoprotein X may play a role in the development of renal impairment in individuals with FLD. However, the effect might be less significant in individuals with acquired LCAT deficiency.

Cardiovascular operation: A significant risk factor of arytenoid cartilage dislocation/subluxation after anesthesia

Background:

Arytenoid cartilage dislocation/subluxation is one of the rare complications following tracheal intubation, and there have been no reports about risk factors leading this complication. From our clinical experience, we have an impression that patients undergoing cardiovascular operations tend to be associated with this complication.

Aims:

We designed a large retrospective study to reveal the incidence and risk factors predicting the occurrence and to examine whether our impression is true.

Settings and Designs:

This was a retrospective study.

Methods:

We retrospectively studied 19,437 adult patients who were intubated by an anesthesiologist in our operation theater from 2002 to 2008. The tracheal intubation was performed by a resident anesthesiologist managing the patients. Only patients whose postoperative voice was disturbed more than 7 days were referred to the Department of Otorhinolaryngology-Head and Neck Surgery and examined using laryngostroboscopy by a laryngologist to diagnose arytenoid cartilage dislocation/subluxation. We evaluated age, sex, weight, height, duration of intubation, difficult intubation, and major cardiovascular operation as risk factors to lead this complication.

Statistical Analysis:

The data were analyzed by logistic regression analysis to assess factors for arytenoid cartilage dislocation/subluxation after univariate analyses using logistic regression analysis.

Results:

Our analysis indicated that difficult intubation (odds ratio: 12.1, P = 0.018) and cardiovascular operation (odds ratio: 9.9, P < 0.001) were significant risk factors of arytenoid cartilage dislocation/subluxation.

Conclusion:

The present study demonstrated that major cardiovascular operation is one of the significant risk factors leading this complication.

A case of feline gastrointestinal eosinophilic sclerosing fibroplasia limited to the mesentery

An entire, female, mixed‐breed cat of unknown age was presented with a 6‐week history of lethargy, anorexia and vomiting. There was an increase in the number of white blood cells in the blood, including neutrophils and eosinophils; moderate anaemia; ascites; and possible mesenteric peritonitis. Exploratory laparotomy revealed firm, multifocal small nodules in the mesentery. As the nodules were surgically unresectable, they were biopsied. Histologically, the nodules were composed of thin trabeculae of dense collagen fibres mixed with plump fibroblasts and numerous eosinophils, consistent with feline gastrointestinal eosinophilic sclerosing fibroplasia. Bacteria were not detected on histological examination of the nodules and cytology of the ascites. Remission of disease occurred following treatment with prednisolone and ciclosporin A for 22 days and antibiotics for 40 days. After remission, ciclosporin A was administered for 236 days and then discontinued. Eosinophilia also resolved after treatment with ciclosporin A. The cat is still alive and in good condition on day 689. This report describes what may be an atypical case of feline gastrointestinal eosinophilic sclerosing fibroplasia, lacking involvement of the gastrointestinal tract, and was apparently cured by treatment that involved ciclosporin A.

Distribution Control-Oriented Intercalation of a Cationic Metal Complex into Layered Silicates Modified with Organosulfonic-Acid Moieties

A layered sodium silicate, octosilicate (Na₂Si₈O₁₇· nH₂O), was modified with an organosulfonic-acid moiety (sulfonated propyl (SPr) group, sulfonated phenethyl (SPhE) group, or sulfonated p-trifluoromethylphenyl (STFPh) group) for use as a host material to accommodate a cationic guest, tris(2,2'-bipyridine)ruthenium(II) cation ([Ru(bpy)₃]²⁺). The organosulfonic-acid moiety was bound to the silicate layer via a reaction of an alkylammonium-exchanged octosilicate with a silane coupling agent, and subsequent treatment (oxidation or sulfonation) of the bound organosilyl groups; the surface densities of the organosulfonic-acid moiety were varied by controlling the added amount of silane coupling agents. Adsorption of [Ru(bpy)₃]²⁺ onto surface-modified octosilicates was conducted to find that some surface-modified octosilicates successfully adsorbed [Ru(bpy)₃]²⁺ in the interlayer space (intercalation), while other surface-modified octosiliates did not. In addition, the UV-vis absorption and the luminescence indicate that intercalated [Ru(bpy)₃]²⁺ diffused in the interlayer and that the distribution of the time-averaged location varied depending on the kind and amount of the organosulfonic-acid moieties. Thus, the kind and surface density of the organosulfonic-acid moiety, which correlates to the interactions between the group and the guest species, the volume of free nanospace for adsorption and motion of guests, and the swelling properties, are the key factors not only for the intercalation ability but also for the dynamics of the guest in the interlayer space.

Classification of Acceleration Waveforms during Walking by Wavelet Transform

In this study we have attempted to classify the acceleration signal, while walking both at horizontal level, and upstairs and downstairs, using wavelet analysis. The acceleration signal close to the body’s center of gravity was measured while the subjects walked in a corridor and up and down a stairway. The data for four steps were analyzed and the Daubecies 3 wavelet transform was applied to the sequential data. The variables to be discriminated were the waveforms related to levels -4 and -5. The sum of the square values at each step was compared at levels -4 and -5. Downstairs walking could be discriminated from other types of walking, showing the largest value for level -5. Walking at horizontal level was compared with upstairs walking for level -4. It was possible to discriminate the continuous dynamic responses to walking by the wavelet transform.

Standard morphology of the oral commissure and changes resulting from reconstruction for defects involving the commissure

The aim of this study was to characterize the standard morphology of the oral commissure and to describe the changes after reconstruction in patients with through-and-through cheek defects involving the oral commissure. Indices for the morphological analyses of the commissure were derived from examinations of 50 normal Japanese volunteers. Ten patients with full-thickness cheek defects involving the commissure were then evaluated. All of these patients underwent free flap reconstruction with vermilion advancement flaps from the remaining vermilion. The morphology of the commissure with the mouth closed was classified based on the point of entrance of the vermilion into the oral cavity. In normal volunteers, the commissure pattern consisting of the entrance of the upper vermilion into the oral cavity before the lower vermilion and just prior to forming the oral commissure was considered to be the standard. However, in the reconstructed cases, there was an increase in the pattern in which the lower vermilion enters the oral cavity before the upper vermilion for the remaining commissure postoperatively, especially when the lower lip defects were greater than those of the upper lip. It is important to refer not only to the standard morphology of the commissure, but also to the changes according to the extent of resection and the method of reconstruction.

Control of the optical properties of cadmium selenide nanoparticles using magadiite

The preparation of cadmium selenide nanoparticles in the interlayer space of magadiite, a layered sodium silicate, modified with the cetyltrimethylammonium cation was studied. The preparation was based on the formation of cadmium selenide by the reaction between the cetyltrimethylammonium modified magadiite and an aqueous mixture of cadmium sulfate and sodium selenosulfite at room temperature. The resulting hybrids were characterized by XRD, FT-IR, HRTEM, TG-DTA, as well as UV-visible and photoluminescence spectroscopy. The expansion of the interlayer spaces as well as TG-DTA results indicated the presence of the cetyltrimethylammonium cation and cadmium selenide in the hybrids. The HRTEM images showed the presence of cadmium selenide in the diameter range of 2-3 nm in the interlayer space of magadiite. The luminescence intensity of the cadmium selenide varied depending on the particle size, which was controlled by the loading amount of cadmium selenide precursor.

Precise Synthesis of Well-Defined Inorganic-Organic Hybrid Particles

Synthesis of hybrid particles toward precisely designed hierarchical nanoarchitectures is summarized. In order to satisfy the demands for a variety of materials' performances, the selection of materials, composition and synthesis is carefully done. Flow reactors are one of the useful synthetic means to prepare hybrid materials, especially those with hierarchically and precisely designed multi-components hybrid particles, owing to the efficient mixing and heat exchange in the reactor as well as its connectable (both parallel and sequential) feature. In this review article, after the summary of the preparation of hybrids based on oxides and organics through conventional batch reactors, the application of flow reactors to the preparation of various hybrid particles is introduced to highlight the present status and future possibility of the flow reactor synthesis.

Mechanochemical methods for the preparation of intercalation compounds, from intercalation to the formation of layered double hydroxides

Mechanochemical methods (solid–solid reactions under ambient conditions or solvent free synthesis) are useful for the preparation of intercalation compounds.

Size-Controlled Synthesis of Anatase in a Mesoporous Silica, SBA-15

The preparation of anatase in the cylindrical mesopore of SBA-15 (pore size of 8 nm) was done by the impregnation of tetraisopropyl orthotitanate and its subsequent crystallization. The impregnation was done without a solvent. Hydrolysis and condensation were promoted by the HCl vapor to encapsulate a larger amount of titanium oxo species in the mesopore and to suppress the desorption of the titanium oxo species during crystallization to anatase. After the reaction, the shape of the N₂ adsorption isotherm changed significantly, indicating the decrease of the Brunauer-Emmett-Teller surface area from 743 to 283 m²/g and of the pore volume from 1.27 to 0.26 cm³/g, respectively. After the crystallization to anatase, the TiO₂ content in the product was estimated to be 62 mass %, filling 30% of the pore volume of SBA-15. The homogeneous distribution of titanium in the SBA-15 sample was confirmed by elemental mapping based on scanning electron microscopy/energy-dispersive X-ray spectrometry. The crystal size of the anatase was determined to be ca. 8.1 nm, which is consistent with the pore size of the used SBA-15 (8.0 nm, derived from the Barrett-Joyner-Halenda analysis of the nitrogen adsorption isotherm). The zeta potential measurements showed the absence of anatase as isolated particles or on the surface of SBA-15 particles. All of these characterizations confirmed the successful size-controlled synthesis of anatase in the mesopore of SBA-15.

Deposition of a titania layer on spherical porous silica particles and their nanostructure-induced vapor sensing properties

A titania-stearic acid hybrid layer was deposited onto well-defined silica-hexadecyltrimethylammonium hybrid spherical particles with 854 nm size to obtain nanoporous particles with a useful hierarchical core-shell structure. The deposition of a 35 nm-thick titania layer was confirmed by transmission electron microscopy. The core-shell particles were washed with acidic ethanol (solvent extraction) and calcined at 550 °C for 5 h to remove the template, resulting in the formation of nanoporous titania coated nanoporous silica spherical particles, which have a bimodal pore size distribution attributed to the hierarchical porous core and porous shell structure. The nanoporous titania coated particles exhibited an unusual crystal phase transition; only anatase was present even after the calcination at 1000 °C for 1 h. This would be due to the interfacial bonding between the core silica and the shell titania, preventing the crystal phase transition from anatase to rutile. On the other hand, the direct calcination of the titania-stearic acid coated particles without solvent extraction led to a shell composed of both anatase and rutile. The transformation to rutile could be caused by the strong exothermic reaction during the oxidative decomposition of the occluded stearic acid. Furthermore, the intense exothermic reaction induced the formation of a yolk-shell structure, which played a role in the sensitive/selective sensing properties for acetic acid when the yolk-shell particles were coated onto a nanomechanical Membrane-type Surface stress Sensor (MSS).