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Allyl cellulose is an important intermediate for cellulose functionalization because of the high reactivity of the allyl group. In this work, a rapid allylation of cellulose with allyl bromide was realized under mild ambient conditions by using a cellulose solvent, tetra-n-butylphosphonium hydroxide aqueous solution, for the reaction medium. The allylation proceeded with a consecutive change in the state of the reaction system from the initial transparent liquid through a colloidal emulsion to the definitive suspension. The reaction conducted for 1 h yielded allyl cellulose showing a degree of substitution (DS) of ~ 2.0; virtually, however, the substitution to DS ≈ 1.9 was attained at the stage of 10 min elapsing. The reaction behavior was interpreted in terms of a model scheme proposed previously for cellulose benzylation using a similar reaction medium. The allyl products indexed with such a relatively high DS (> 1.8) were well soluble in various organic solvents. It was also shown that the present synthetic process gave rise to no serious degradation of the cellulose main chains nor cross-linking between the introduced allyl groups.

Visual hallucinations occur in individuals with paroxysmal neurological diseases, such as epilepsy and migraine, alcohol withdrawal, use of anticholinergic or hallucinogenic drugs, neurodegenerative diseases, focal brain injury, and schizophrenia spectrum disorders. In this review, I discuss the phenomenology and pathophysiology of the 11 clinical conditions associated with visual hallucinations and their related symptoms.

Mirror writing (MW) is the production of individual letters, words, or word strings in the reverse direction. Parkinson’s disease (PD) is a progressive neurodegenerative disorder, and high MW rates have been reported in patients with PD. Thus, the present study sought to identify the factors that cause MW in patients with PD. We examined the frequency of MW in patients with PD and investigated the area of the brain where such frequency inversely correlates with reduced regional cerebral metabolic rates of glucose (rCMRglc). We also examined whether this area satisfied the motor and visual monitoring hypotheses of MW that have been presented in previous studies. Thirty-six subjects with idiopathic PD and 23 healthy controls were included in the study. We asked the participants to write down words, numerals, and sentences from left to right using their dominant and non-dominant hands. Patients with PD underwent an 18F-fluorodeoxyglucose positron emission tomography scan to measure the rCMRglc. Neither the patients with PD nor the healthy subjects exhibited MW in the use of the right hand. In the use of the left hand, MW occurred in 15 of the 36 patients with PD, but in none of the healthy controls. The right intraparietal sulcus was identified as the area where rCMRglc was inversely correlated with the number of left–right reversed characters. Previous functional imaging studies have suggested that the right superior parietal cortex and intraparietal sulcus play an important role in recognizing left–right reversed letters. Therefore, dysfunction in the intraparietal sulcus may hinder the recognition of left–right reversed characters, resulting in MW. Consequently, our findings in patients with PD are consistent with the visual-monitoring hypothesis of MW.

Highlights • We assessed the perception of illusory contours in patients with PD. • PD patients showed difficulty in perceiving Kanizsa illusory figures. • Impaired perception of Kanizsa illusory figures was related to LOC hypometabolism., Neuroimaging evidence suggests that areas of the higher-order visual cortex, including the lateral occipital complex (LOC), are engaged in the perception of illusory contours; however, these findings remain unsubstantiated by human lesion data. Therefore, we assessed the presentation time necessary to perceive two types of illusory contours formed by Kanizsa figures or aligned line ends in patients with Parkinson's disease (PD). Additionally, we used 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) to measure regional cerebral glucose metabolism in PD patients. Although there were no significant differences in the stimulus durations required for perception of illusory contours formed by aligned line ends between PD patients and controls, PD patients required significantly longer stimulus durations for the perception of Kanizsa illusory figures. Difficulty in perceiving Kanizsa illusory figures was correlated with hypometabolism in the higher-order visual cortical areas, including the posterior inferior temporal gyrus. These findings indicate an association between dysfunction in the posterior inferior temporal gyrus, a region corresponding to a portion of the LOC, and impaired perception of Kanizsa illusory figures in PD patients.

CaCO3 mineralization was carried out using cellulose nanocrystal (CNC)/polymer composites wherein a chiral nematic structure of CNC assembly was immobilized in advance via a polymerization process of the precursory aqueous CNC/vinyl monomer lyotropics (7–11 wt% CNC in feed). Two series of polymer composites were prepared: CNC/poly(2-hydroxyethyl methacrylate) (PHEMA) and CNC/poly(2-hydroxyethyl methacrylate-co-acrylic acid) (P(HEMA-co-AA), HEMA:AA = 95:5–70:30 in mol). The mineralization was allowed to proceed solely by soaking the composite films in a salt solution containing Ca2+ and HCO3− under a low-basic condition (pH ≤ 9). Polymorphism of CaCO3 deposited inside the films was examined by X-ray diffractometry as a function of the soaking time (1–5 day) and also of the matrix composition. In the CNC/PHEMA series, the polymorphic form changed from amorphous calcium carbonate (ACC) (1-day soaking) to metastable crystalline vaterite (3-day soaking) and then to a mixture of vaterite and aragonite (5-day soaking). In the mineralization of the CNC/P(HEMA-co-AA) series, the formation of stable calcite was prominent besides minor appearance of vaterite. It was deduced that the mesofiller CNC and the AA unit in the vinyl polymer, both bearing an anionic group (-SO3− or -COO−), contributed to capturing Ca2+ to facilitate the CaCO3 deposition in the swollen film matrix. The pre-invested chiral nematic organization was kept in any of the mineralized films (dried); however, the helical pitch was appreciably reduced relative to that observed before the mineralization, attributable to the increase of ionic strength in the CNCs' surroundings accompanied by the wet process. Thermogravimetry showed that the mineralization definitely improved the thermal performance (heat/flame resistance) of the mesomorphic order-retaining CNC/polymer composites.

For new application of technical lignins as separator material for electric double-layer capacitor (EDLC), we tried first to prepare bipolyester film by melt-polycondensation of polyethylene glycol lignin (PEGL) and maleic anhydride. The EDLC assembled with this film, however, showed lower electrochemical performance than the reference EDLC with commercial cellulosic separator. Porous bipolyester film was then prepared and the resulting EDLC exhibited improved specific capacitance, but high intrinsic and charge transfer resistances. Non-porous terpolyester film was prepared next, using polyethylene glycol 500,000 to improve flexibility of the film, which might lower the resistances. This film was flexible enough and provided the resulting EDLC with superior electrochemical performance to the bipolyester film. EDLC with porous terpolyester film was finally prepared and showed the highest electrochemical performance, comparable to the reference EDLC. Porous morphology and flexibility were key factors to fabricate lignin-based self-standing film as separator material for high-performance EDLC.

An attempt was made to fabricate optically functional cellulosic–silica hybrid materials wherein a helically ordered mesomorphic structure of the cellulosic component was fixed. Cellulose 3-chlorophenylcarbamate (3Cl-CPC) and cellulose 4-chlorophenylcarbamate (4Cl-CPC) were synthesized by carbanilating reaction of cellulose with 3-chlorophenyl or 4-chlorophenyl isocyanate in a homogeneous solution system. The hydrophobic cellulose derivatives were examined for the solubility and liquid crystallinity in various solvents containing alkoxysilane as a main component. Concentrated (∼40 wt%) solutions of 3Cl-CPC in 3-aminopropyltrimethoxysilane (APTMS) and those of 4Cl-CPC in a mixed solvent of tetramethoxysilane (TMOS)/N,N-dimethylformamide (DMF)/dichloroacetic acid (DCA) formed a chiral nematic mesophase to impart vivid reflection colors. These liquid crystalline solutions were subjected to a sol–gel conversion process of the respective alkoxysilane components in moist air. In the process for the 4Cl-CPC lyotropic system, we utilized a "surface-coating solvent" consisting of TMOS/phenyltrimethoxysilane/DCA to facilitate the sol–gel reaction of TMOS and also to preserve the reflective coloration. Thereby a left-handed chiral nematic hybrid series of 4Cl-CPC–silica was successfully obtained as a monolithic glassy bulk showing iridescent colors. The 3Cl-CPC/APTMS lyotropics were readily converted into a colored solid form without any coating solution, resulting in production of a right-handed chiral nematic series of 3Cl-CPC–silica. Besides investigating the chiroptical characteristics of the liquid crystalline solutions and hybrids, we preliminarily tried separating a racemic compound into two enantiomers by open column chromatography using the cellulosic–silica hybrids as a filler material of the column.

Primary progressive aphasia (PPA) is a neurological syndrome characterized by progressive language impairment. Various neurodegenerative disorders cause PPA. Dementia with Lewy bodies (DLB) is one known cause of PPA, and little is known about this association. Almost all published cases of PPA associated with DLB are the logopenic variant of PPA. Here, we describe the novel case of a patient with DLB presenting clinical features of the semantic variant PPA (svPPA). A 75-year-old woman was referred to our hospital with a 2-year history of progressive anomia and amnesia. Two months before admission, she had been experiencing visual hallucinations, and at the age of 60 years, she had venous infarction in the left temporal lobe, which she recovered from without any residual symptoms. Upon admission to our hospital, she displayed anomia, impaired single-word comprehension, and surface dyslexia with preserved repetition and speech production. These symptoms met the criteria for the diagnosis of svPPA. 123I-ioflupane single-photon emission computed tomography and 123I-meta-iodobenzylguanidine myocardial scintigraphy indicated DLB. Thus, she was administered donepezil, and this dramatically improved her symptoms. We hypothesize that the combination of DLB with the previous asymptomatic venous thrombosis in the left temporal lobe may have contributed to the “svPPA” in this patient. In conclusion, we show that PPA associated with DLB could be treated with donepezil, and we suggest that donepezil should be pursued as a treatment option for PPA., Highlights • Primary progressive aphasia is characterized by progressive language impairment. • We report a case of primary progressive aphasia and dementia with Lewy bodies. • MRI showed a previously found asymptomatic lesion in the left temporal lobe. • A cholinesterase inhibitor improved cognitive functions, including language. • Comorbidity disrupted the recovery of temporal lobe function and impaired language.

Anterior temporal lobectomy (ATL) is the most common surgical treatment for drug-resistant temporal lobe epilepsy (TLE). Right ATL has been reported to reduce facial memory ability in patients with TLE, as indicated by poor performance on the Warrington Recognition Memory Test for Faces (RMF), which is commonly used to evaluate visual memory in these patients. However, little is known about whether patients with TLE exhibit difficulties in identifying faces in daily life after ATL. The aim of this study was to investigate facial memory ability and self-awareness of face identification difficulties in patients with TLE after ATL. Sixteen patients with TLE after right ATL, 14 patients with TLE after left ATL, and 29 healthy controls were enrolled in this study. We developed the multiview face recognition test (MFRT), which comprises a learning phase (one or three frontal face images without external facial feature information) and a recognition phase (frontal, oblique, or noise-masked face images). Facial memory abilities were examined in all participants using the MFRT and RMF, and self-awareness of difficulties in face identification was evaluated using the 20-item prosopagnosia index (PI20), which has been widely used to assess developmental prosopagnosia. The MFRT performance in patients with TLE after ATL was significantly worse than that in healthy controls regardless of the resected side, whereas the RMF scores in patients with TLE were significantly worse than those in healthy controls only after right ATL. The MFRT performance in patients with TLE after both left and right ATL was more influenced by working memory load than that in healthy controls. The PI20 scores revealed that patients with TLE after left ATL were aware of their difficulties in identifying faces. These findings suggest that patients with TLE not only after right ATL but also after left ATL might have difficulties in face identification.

OBJECTIVE: This study aimed to examine echolalia and its related symptoms and brain lesions in primary progressive aphasia (PPA). METHODS: Forty-five patients with PPA were included: 19 non-fluent/agrammatic variant PPA (nfvPPA), 5 semantic variant PPA, 7 logopenic variant PPA, and 14 unclassified PPA patients. We detected echolalia in unstructured conversations. An evaluation of language function and the presence of parkinsonism, grasp reflex, imitation behaviour, and disinhibition were assessed. We also measured regional cerebral blood flow (rCBF) using single-photon emission computed tomography. RESULTS: Echolalia was observed in 12 nfvPPA and 2 unclassified PPA patients. All patients showed mitigated echolalia. We compared nfvPPA patients with echolalia (echolalia group) to those without echolalia (non-echolalia group). The median age of the echolalia group was significantly lower than that of the non-echolalia group, and the echolalia group showed a significantly worse auditory comprehension performance than the non-echolalia group. In contrast, the performance of repetition tasks was not different between the two groups. The prevalence of imitation behaviour in the echolalia group was significantly higher than that in the non-echolalia group. The rCBFs in the bilateral pre-supplementary motor area and bilateral middle cingulate cortex in the echolalia group were significantly lower than those in the non-echolalia group. CONCLUSIONS: These findings suggest that echolalia is characteristic of nfvPPA patients with preserved repetition and impaired comprehension. Reduced inhibition of the medial frontal cortex with release activity of the anterior perisylvian area account for the emergence of echolalia.

Highlights • Pathological basis of primary progressive aphasia is heterogeneous. • Logopenic primary progressive aphasia can precede dementia with Lewy bodies (DLB). • Cholinesterase inhibitor can improve logopenic aphasia with DLB.

(Hydroxypropyl)cellulose (HPC) derivatives with butyryl (Bu) and heptafluorobutyryl (7FBu) substituents were prepared in various proportions of the Bu/7FBu groups and at a fixed total DS (DSBu + DS7FBu) of 3.0. Thermotropic liquid crystallinity of the derivatives (Bu7FBu-HPC) was investigated to specify the effect of the fluoroacylation on the mesophase behavior. Thermal transition data were collected using differential scanning calorimetry and polarized light microscopy. The Bu7FBu-HPC samples formed a chiral nematic phase between their glass transition and isotropization temperatures, Tg and Ti-a, respectively; these transition temperatures rose moderately as the 7FBu proportion increased (Tg = − 44 to − 27 °C and Ti-a = 158–190 °C for DS7FBu = 0.04–1.60). The structural property of the mesophase was examined at 70 °C by circular dichroism and other optical measurements. The chiral nematic pitch (P) sensitively increased with increasing 7FBu proportion, while the supramolecular helical arrangement remained right-handed. Selective light-reflection colors were observed for the samples of DS7FBu = 0.04–0.8, covering an entire spectrum range from violet to red. Temperature dependence of P was also examined for selected samples below Ti-a, and it was found to increase with increasing temperature; however, there was no indication of inversion in the handedness of the helical structure. Wide-angle X-ray diffractometry revealed that the increases of P responding to the increases in DS7FBu and temperature were attributable to the decrease of the twist angle between adjacent thin nematic layers.

Recently we developed a self-standing and flexible lignin-based polyester film (LPF) as a separator for electric double-layer capacitor (EDLC). However, the film showed very low mechanical strength. In this study, reinforcement of LPF was attempted with TEMPO-oxidized cellulose nanofiber (TOCN). Modulus of elasticity was remarkably increased with an increase in TOCN content. By 1% addition of TOCN, tensile strength at failure was also significantly increased with its flexibility maintained, resulting in the highest strain energy density among tested samples. Zero-span tensile test revealed that the improved tensile strength was caused by the TOCN strength. In addition, dynamic mechanical analysis and differential scanning calorimetry demonstrated that TOCN suppressed thermal deformation of LPF at elevated temperature. However, TOCN did not affect the tensile impact strength of the LPF. Finally, EDLC was assembled with the TOCN-reinforced LPF as a separator, hand-made electrodes with commercial activated carbon and conductive carbon black, and triethylmethylammonium tetrafluoroborate/propylene carbonate as an organic electrolyte. Although this EDLC showed higher specific capacitance than EDLC with commercial cellulosic separator as a reference, intrinsic and charge transfer resistances of this EDLC were much higher than those of the reference EDLC. By conversion of the LPF to porous film, the resistances were dramatically improved, and the specific capacitance was further enhanced. Consequently, LPF reinforced with 1% TOCN is a promising separator for EDLC.

Objective To identify the phenomenological features and neural correlates of visual illusions in Parkinson's disease (PD). Methods Ninety-three patients with PD were assessed via questionnaires regarding visual illusions and behavioral symptoms, and neuropsychological tests, motor assessments and 18-F fluorodeoxyglucose-positron emission tomography (FDG-PET) were performed. The relationship between visual illusions or hallucinations and regional cerebral glucose metabolism was investigated using partial least squares (PLS) correlation and conventional mass-univariate analyses. Results Kinetopsia, in which stationary objects are perceived as being in motion, and object misidentification illusions, in which objects are misperceived as different objects, were the most common types of visual illusions. Kinetopsia and object misidentification illusions were identified in 24 patients (25.8%) and 17 patients (18.3%), respectively. Eleven patients with kinetopsia and 9 patients with object misidentification illusions had visual hallucinations. Kinetopsia and visual hallucinations were associated with hypometabolism in the temporo-parietal cortices, whereas object misidentification illusions were associated with hypometabolism in the early visual cortex, as well as the temporo-parietal cortices. Conclusions Our findings suggest that kinetopsia and object misidentification illusions are the most common types of visual illusions in PD. Despite the phenomenological diversity of visual illusions and hallucinations in PD, all of these symptoms are associated with dysfunction of the temporo-parietal cortices, which support visual spatial processing, rather than dysfunction of the ventral temporo-occipital cortices, which supports visual object recognition.

Background and purposeWe previously reported the usefulness of iodine-123 metaiodobenzylguanidine (123I-MIBG) myocardial scintigraphy for differentiation of dementia with Lewy bodies (DLB) from Alzheimer’s disease (AD) in a cross-sectional multicentre study. The aim of this study was, by using reassessed diagnosis after 3-year follow-up, to evaluate the diagnostic accuracy of 123I-MIBG scintigraphy in differentiation of probable DLB from probable AD.MethodsWe undertook 3-year follow-up of 133 patients with probable or possible DLB or probable AD who had undergone 123I-MIBG myocardial scintigraphy at baseline. An independent consensus panel made final diagnosis at 3-year follow-up. Based on the final diagnosis, we re-evaluated the diagnostic accuracy of 123I-MIBG scintigraphy performed at baseline.ResultsSixty-five patients completed 3-year follow-up assessment. The final diagnoses were probable DLB (n=30), possible DLB (n=3) and probably AD (n=31), and depression (n=1). With a receiver operating characteristic curve analysis of heart-to-mediastinum (H/M) ratios for differentiating probable DLB from probable AD, the sensitivity/specificity were 0.77/0.94 for early images using 2.51 as the threshold of early H/M ratio, and 0.77/0.97 for delayed images using 2.20 as the threshold of delayed H/M ratio. Five of six patients who were diagnosed with possible DLB at baseline and with probable DLB at follow-up had low H/M ratio at baseline.ConclusionsOur follow-up study confirmed high correlation between abnormal cardiac sympathetic activity evaluated with 123I-MIBG myocardial scintigraphy at baseline and the clinical diagnosis of probable DLB at 3-year follow-up. Its diagnostic usefulness in early stage of DLB was suggested.Trial registration numberUMIN00003419.

Ionic complexes consisting of a mesogenic cholesterol derivative and 1-alkyl (Cn)-3-methylimidazolium (CnMim) (n = 6–18) were prepared from ethanol solutions containing an equimolar mixture of cholesterol hydrogen phthalate (CHP) and 1-Cn-3-methylimidazolium hydroxide; the imidazolium hydroxide was obtained by anion exchange of 1-Cn-3-methylimidazolium bromide. The complex samples, termed [CnMim][CHP], were examined to evaluate their thermal transition patterns. Excluding the two samples (n = 6, 8) that showed no definite ordered phase, the complexes with n ≥ 10 formed a cholesteric (n = 10, 12) or smectic (n = 14–18) mesophase in a considerably wide range of temperatures; this wide range reflects the additional thermotropic property of the salts of CnMim with longer alkyl chains. These fluid mesophases transformed into a mesomorphic vitreous solid without crystallization in a usual cooling process. For the glassy mesomorphic samples of selected complexes (n = 10, 18), the enthalpy relaxation behavior was followed as a function of the aging temperature and time, and the data were analyzed in terms of a Kohlrausch–Williams–Watts (KWW) type of stretched exponential equation. A very narrow distribution of relaxation times was observed for the “liquid crystalline glasses”, indicating the high uniformity of the relaxation mode. We prepared a series of ionic complexes, [CnMim][CHP] (n = 6–18), by neutralizing cholesterol hydrogen phthalate (CHP) with 1-alkyl (Cn)-3-methylimidazolium hydroxide ([CnMim][OH]) derived from [CnMim][Br]. The complexes of n ≥ 10 formed a thermotropic mesophase in each individual temperature range and solidified into a mesomorphic glass upon cooling, although two samples of n = 6 and 8 showed no ordered structure. Enthalpy relaxation behavior of the mesomorphic glasses (n = 10, 18) was also examined as a function of the aging temperature and time

A CaCO3 mineralization was carried out using a mesomorphic network system composed of ethyl cellulose (EC) and poly(acrylic acid) (PAA), to realize a polymer–inorganic hybrid invested with a chiroptical functionality and thermal and mechanical high-performances. The EC/PAA samples were prepared in colored film form from chiral nematic liquid crystals of EC in acrylic acid (AA) by polymerization and cross-linking of the solvent monomer AA. The mineralization was allowed to proceed in a batchwise operation by immersing and swelling the liquid-crystalline polymer films in an aqueous salt solution providing Ca2+, HCO3−, and additional Mg2+ ions. By varying the ionic condition (i.e., pH and Mg/Ca ratio) of the employed salt solution, calcite (Cal), aragonite (Ara), and solely amorphous CaCO3 (ACC) were separately deposited inside the EC/PAA matrices. Irrespective of the polymorphs of the incorporated CaCO3, the mineralized EC/PAA films (weight gain, ca. 20–28%) retained the original left-handed chiral nematic arrangement and exhibited a reflective color that was shifted to the red side relative to that of the corresponding nonmineralized films. It was also confirmed that the inorganic hybridization remarkably enhanced the thermal and thermomechanical properties of the optically functionalized EC/PAA films. In thermogravimetric analysis data above 300 °C, however, a significant difference was observed between the three sorts of hybrids with Cal, Ara, and ACC, respectively.

We propose a method for preparing magnetically anisotropic soft materials that includes chemical loading (in situ synthesis) of iron oxide nanoparticles in a matrix composed of κ-carrageenan (Car) and poly(vinyl alcohol) (PVA) followed by mechanical stretching of the hybrid in a wet process. Anionic Car was used to accommodate the iron oxide nanoparticles and was blended in advance with PVA, which has the ability of high orientation. Scanning electron microscopy revealed that the loaded granular iron oxide nanoparticles (50–100 nm) formed elliptical clusters upon stretching of the hybrid composite. Wide-angle X-ray diffraction measurements indicated that the PVA constituent was oriented in the draw direction. With the orientation of the composite matrix, the incorporated iron oxide nanoparticles gathered to form elliptical clusters. The drawn samples showed different amplitudes in the magnetization (M|| > M⊥) when measured in two setups in which the applied field was parallel (||) or perpendicular (⊥) to the draw direction. The specific responses of the drawn sheets to an external magnetic stimulus were visualized and were reasonably attributed to an effect of the magnetic anisotropy created by the preferred orientation of the nanoparticle aggregates. We prepared magnetically anisotropic soft materials by in situ synthesis of iron oxide nanoparticles in a matrix composed of κ-carrageenan and PVA followed by mechanical stretching of the hybrid in a wet process. With the orientation of the composite matrix, the incorporated iron oxide nanoparticles gathered to form elliptical clusters. The drawn samples showed different magnetizations depending on the direction of magnetic field application. The specific responses were macroscopically visualized and were attributed to the magnetic anisotropy created by the preferred orientation of the nanoparticle aggregates.

A series of fluorescent cellulose derivatives (AC-AET-DMANMs) with different degrees of substitution (DS) were successfully prepared. First, allyl cellulose (AC) was synthesized from cellulose in NaOH/urea aqueous solution, and then 2-aminoethanethiol (AET) was introduced onto the cellulose backbone via a thiol–ene click reaction. Finally, the fluorescent groups were introduced by the reaction of the AET-modified AC with 4-dimethylamine-1,8-naphthalic anhydride (DMANA). The structure and fluorescent properties of AC-AET-DMANMs were characterized by elemental analysis and FT-IR, 1H NMR, UV–vis, and fluorescence spectroscopy. AC-AET-DMANM with lower DSDMANM (referring to the DS of naphthalimide groups, ≤0.25) was soluble in DMSO. AC-AET-DMANM of DSDMANM ≤ 0.09 displayed stable fluorescence in DMSO and even in the solid state. The emission of AC-AET-DMANM in DMSO quantitatively and sensitively responded to 2,4,6-trinitrophenol (TNP) and 2,4-dinitrophenylhydrazine (DNH) by fluorescence quenching, and the limi...

We found a very fast benzylation of cellulose in a tetraalkyl-onium hydroxide solvent system, 47% tetra-n-butylphosphonium hydroxide aqueous solution. Benzyl cellulose (BC) with a degree of substitution (DS) above 2.5 was obtained within 10 min at ambient temperature (20–25 °C) using ∼9 mol equiv of benzyl bromide to the anhydroglucose unit. The highly efficient benzylation proceeded in the transiently stabilized emulsion state of the reaction system, and the product precipitated out as a solid sediment in the liquid medium. At 20 °C, the benzyl DS was 1.92 after 2 min, and reached 2.40 and 2.53 after 5 and 10 min, respectively. The reaction temperature had a negative correlation with the maximum DS in the explored range of 10–50 °C. No significant degradation of the cellulosic main chain was observed for highly substituted BCs (DS > 2.5). The solubility of BC in common organic solvents was also examined for products with various DSs.

CaCO

Magnetically anisotropic materials were fabricated in film form from cellulose nanocrystal (CNC)/ ι -carrageenan ( ι -Car) gelatinous composites (5–30 wt% CNC) via repeated “ in situ synthesis” of iron oxide nanoparticles therein and subsequent drawing of the inorganic–polysaccharide hybrids in a wet process. Basic magnetic properties of the film samples were examined by superconducting quantum interference device (SQUID) magnetometry. After three cycles of the in situ synthesis process, the saturation magnetization of as-dried (undrawn) hybrid samples reached a practically high value of 15 emu (g sample) −1 thereabout at 298 K, reflecting a remarkable capacity of ι -Car as a gel matrix for the iron oxide synthesis. The drawn samples showed different amplitudes in the magnetization ( M || > M ⊥ ) when measured in two setups where the applied field was parallel (||) or perpendicular (⊥) to the draw direction. The extent of the anisotropy was relatively higher at the composition of CNC/ ι -Car = 10/90 (w/w) than the other explored compositions, indicating that ∼10 wt% is an optimal concentration of CNC as orientation promoter in the drawing of such inorganic-hybridized ι -Car networks. Morphological observations were made for selected drawn hybrids by FE-SEM and atomic force/magnetic force microscopy. It was revealed that iron oxide nanoparticles (10–30 nm ϕ ) were assembled in a long larger aggregate (

Distribution of substituents on the anhydroglucose unit of cellulose (at C2, C3 and C6 positions) is one of the important topics in the derivatization chemistry, but the regioselectivity control is generally difficult. In this report, we exemplified that cellulose acetates having a similar total degree of substitution (∼2.3) were obtained in the relevant derivatization but regioselectivity (C6 > C3 > C2, C2 > C6 > C3, C6 > C2 > C3, or C6 > C3=C2) by a simple one-pot reaction (25 °C; 3 h) with acetyl chloride or acetic anhydride in various ionic liquids (ILs). The order of the regional degree of substitution associated with the C2 and C3 positions was successfully correlated with the variation of anion species incident to the acetylating reagent-IL combination. In the use of acetyl chloride, the observed difference in the substituent distribution was attributable to whether a pre-reaction between the in-fed reagent and the anion moiety of the solvent IL was possible or not.

Background Sleep disturbances in Alzheimer disease (AD) may affect behavioral and psychological symptoms of dementia (BPSD). Our aim was to elucidate the associations between sleep disturbances and other BPSD at different stages of AD. Methods This investigation was part of a multicenter-retrospective study in Japan (J-BIRD). Eligible for final analyses were 684 AD patients. Global severity of dementia was estimated using the Clinical Dementia Rating (CDR) scale. BPSD were assessed using the Neuropsychiatric Inventory (NPI). We analyzed the relationships between sleep disturbances and BPSD at different stages of AD according to the CDR score. Results Among the 684 AD patients, 146 (21.3%) had sleep disturbances. Patients with very early AD (CDR 0.5) and sleep disturbances had significantly more BPSD than those without sleep disturbances, as indicated by the higher prevalence of the following four NPI items: anxiety, euphoria, disinhibition, and aberrant motor behavior. In AD at CDR 2, (moderate AD) only one NPI item (irritability) was affected, while none was affected at CDR 1 (mild AD) and 3 (severe AD). Multiple regression analyses were performed in those with AD having various CDR scores. At CDR 0.5, the presence of sleep disturbances was associated with a high total NPI score (β = 0.32, p

Visual impairment and visual hallucinations are diagnostic signposts of dementia with Lewy bodies (DLB). Visual impairment is easily explicable as a functional impairment that results from damage to the visual cortices, whereas there is currently no compelling explanations for the mechanisms of visual hallucinations and other false perceptions. Here, I review evidence regarding the phenomenology and mechanisms of false perceptions in DLB, and propose that false perceptions maybe behavioral consequence of aberrant cortical state caused by cholinergic insufficiency.

Background and Purpose— Apraxia of speech (AOS) is a motor speech disorder, which is clinically characterized by the combination of phonemic segmental changes and articulatory distortions. AOS has been believed to arise from impairment in motor speech planning/programming and differentiated from both aphasia and dysarthria. The brain regions associated with AOS are still a matter of debate. The aim of this study was to address this issue in a large number of consecutive acute ischemic stroke patients. Methods— We retrospectively studied 136 patients with isolated nonlacunar infarcts in the left middle cerebral artery territory (70.5±12.9 years old, 79 males). In accordance with speech and language assessments, the patients were classified into the following groups: pure form of AOS (pure AOS), AOS with aphasia (AOS-aphasia), and without AOS (non-AOS). Voxel-based lesion–symptom mapping analysis was performed on T2-weighted images or fluid-attenuated inversion recovery images. Using the Liebermeister method, group-wise comparisons were made between the all AOS (pure AOS plus AOS-aphasia) and non-AOS, pure AOS and non-AOS, AOS-aphasia and non-AOS, and pure AOS and AOS-aphasia groups. Results— Of the 136 patients, 22 patients were diagnosed with AOS (7 patients with pure AOS and 15 patients with AOS-aphasia). The voxel-based lesion–symptom mapping analysis demonstrated that the brain regions associated with AOS were centered on the left precentral gyrus. Conclusions— Damage to the left precentral gyrus is associated with AOS in acute to subacute stroke patients, suggesting a role of this brain region in motor speech production.