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1.
Molecules ; 27(18)2022 Sep 19.
Article in English | MEDLINE | ID: mdl-36144870

ABSTRACT

Oxidized sucrose (OS) is a bio-based cross-linking agent with excellent biological safety and environmental non-toxicity. However, the precise structure of OS has not been elucidated owing to its structural complexity and low purity. Accordingly, in this study, complete chemical shift assignments were performed by applying various nuclear magnetic resonance techniques, which permitted the structural and quantitative characterization of the two main OS products, each of which contained four aldehyde groups. In addition, we investigated the use of OS as a cross-linking agent in the preparation of a hydrogel from carboxymethyl chitosan (CMC), one of the most popular polysaccharides for use in biomedical applications. The primary amine groups of CMC were immediately cross-linked with the aldehyde groups of OS to form hydrogels without the requirement for a catalyst. It was found that the degree of cross-linking could be easily controlled by the feed amount of OS during CMC hydrogel preparation and the final cross-linking degree affected the thermal, swelling, and rheological properties of the obtained hydrogel. The results presented in this study are therefore expected to be applicable in the preparation of fully carbohydrate-based hydrogels for medical and pharmaceutical applications.


Subject(s)
Chitosan , Hydrogels , Aldehydes , Amines , Chitosan/chemistry , Hydrogels/chemistry , Polysaccharides , Sucrose
2.
Circ J ; 85(3): 264-271, 2021 02 25.
Article in English | MEDLINE | ID: mdl-33431721

ABSTRACT

BACKGROUND: Coronary artery spasms (CASs), which can cause angina attacks and sudden death, have been recently reported during catheter ablation. The aim of the present study was to report the incidence, characteristics, and prognosis of CASs related to atrial fibrillation (AF) ablation procedures.Methods and Results:The AF ablation records of 22,232 patients treated in 15 Japanese hospitals were reviewed. CASs associated with AF ablation occurred in 42 of 22,232 patients (0.19%). CASs occurred during ablation energy applications in 21 patients (50%). CASs also occurred before ablation in 9 patients (21%) and after ablation in 12 patients (29%). The initial change in the electrocardiogram was ST-segment elevation in the inferior leads in 33 patients (79%). Emergency coronary angiography revealed coronary artery stenosis and occlusions, which were relieved by nitrate administration. No air bubbles were observed. A comparison of the incidence of CASs during pulmonary vein isolation between the different ablation energy sources revealed a significantly higher incidence with cryoballoon ablation (11/3,288; 0.34%) than with radiofrequency catheter, hot balloon, or laser balloon ablation (8/18,596 [0.04%], 0/237 [0%], and 0/111 [0%], respectively; P<0.001). CASs most often occurred during ablation of the left superior pulmonary vein. All patients recovered without sequelae. CONCLUSIONS: CASs related to AF ablation are rare, but should be considered as a dangerous complication that can occur anytime during the periprocedural period.


Subject(s)
Atrial Fibrillation , Catheter Ablation , Coronary Vasospasm , Pulmonary Veins , Atrial Fibrillation/epidemiology , Atrial Fibrillation/surgery , Catheter Ablation/adverse effects , Coronary Vasospasm/epidemiology , Coronary Vasospasm/etiology , Coronary Vessels/diagnostic imaging , Coronary Vessels/surgery , Humans , Incidence , Pulmonary Veins/surgery , Spasm , Treatment Outcome
3.
Biomacromolecules ; 21(2): 581-588, 2020 02 10.
Article in English | MEDLINE | ID: mdl-31749354

ABSTRACT

Nanofibrillated bacterial cellulose (NFBC) is produced by culturing a cellulose-producing bacterium under agitated aerobic conditions in a carboxymethylcellulose (CMC)-supplemented medium. Detailed structural analyses revealed that NFBC fiber widths varied with the degree of substitution of the CMC used, and zeta potential values decreased with the increment of CMC concentration in the medium. Transmission electron microscopy observation after immunostaining demonstrated that CMC molecules were present on the NFBC microfibril surfaces. We tested NFBC for utility as a binder for a display device that uses electrochromic (EC) material. Introduction of a quaternary ammonium group into the EC molecules enhanced their interactions with the negatively charged NFBC microfibrils. A casting process homogeneously adsorbed the EC molecules onto the surface of a transparent electrode with NFBC. A homogeneous color change was successfully observed upon applying an electric field, suggesting that NFBC could be used as a binder material for uniform surface adsorption.


Subject(s)
Cellulose/chemistry , Nanocomposites/chemistry , Carboxymethylcellulose Sodium/chemistry , Color , Fluorescein/chemistry , Fluorescent Dyes/chemistry , Magnetic Resonance Spectroscopy , Microscopy, Electron, Transmission , Quaternary Ammonium Compounds/chemistry , Spectroscopy, Fourier Transform Infrared , Staphylococcus/metabolism , X-Ray Diffraction
4.
Biomacromolecules ; 18(10): 3432-3438, 2017 Oct 09.
Article in English | MEDLINE | ID: mdl-28876907

ABSTRACT

Nanofibrillated bacterial cellulose (NFBC) is produced by culturing a cellulose-producing bacterium (Gluconacetobacter intermedius NEDO-01) with rotation or agitation in medium supplemented with carboxymethylcellulose (CMC). Despite a high yield and dispersibility in water, the product immediately aggregates in organic solvents. To broaden its applicability, we prepared amphiphilic NFBC by culturing strain NEDO-01 in medium supplemented with hydroxyethylcellulose or hydroxypropylcellulose instead of CMC. Transmission electron microscopy analysis revealed that the resultant materials (HE-NFBC and HP-NFBC, respectively) comprised relatively uniform fibers with diameters of 33 ± 7 and 42 ± 8 nm, respectively. HP-NFBC was dispersible in polar organic solvents such as methanol, acetone, isopropyl alcohol, acetonitrile, tetrahydrofuran (THF), and dimethylformamide, and was also dispersible in poly(methyl methacrylate) (PMMA) by solvent mixing using THF. HP-NFBC/PMMA composite films were highly transparent and had a higher tensile strength than neat PMMA film. Thus, HP-NFBC has a broad range of applications, including as a filler material.


Subject(s)
Cellulose/analogs & derivatives , Gluconacetobacter/metabolism , Nanofibers/chemistry , Surface-Active Agents/chemistry , Acetone/chemistry , Alcohols/chemistry , Cellulose/biosynthesis , Polymethyl Methacrylate/chemistry , Solvents/chemistry
5.
Chem Pharm Bull (Tokyo) ; 64(10): 1484-1491, 2016.
Article in English | MEDLINE | ID: mdl-27725501

ABSTRACT

Polyethylenimine (PEI) is one of the most versatile non-viral vectors used in gene therapy, especially for delivering plasmid DNA to human cells. However, a good understanding of PEI binding to DNA, the fundamental basis for the functioning of PEI as a vector, has been missing in the literature. In this study, PEI (branched, 600 Da) binding to DNA was examined by isothermal titration calorimetry (ITC), quartz crystal microbalance (QCM) and a complementary set of analysis tools. We demonstrated that a separation between the binding heat and the condensation heat is needed and that the excluded site model should be used for PEI binding stage in the ITC analysis. The equilibrium constant for PEI binding to DNA was determined to be 2.5×105 M-1 from the ITC analysis, and as 2.3×105 M-1 from the QCM analysis. Additionally, we suggested that the 600 Da branched PEI binds to the major groove of DNA and the rearrangement of PEI on DNA may be difficult to occur because of the small dissociation rate. The binding analysis presented here can be employed to improve our understanding of the functioning of PEI and PEI-like non-viral vectors.


Subject(s)
DNA/chemistry , Polyethyleneimine/chemistry , Binding Sites , Calorimetry , Carbon-13 Magnetic Resonance Spectroscopy , Humans , Molecular Weight , Plasmids , Thermodynamics
6.
J Arrhythm ; 40(2): 333-341, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38586856

ABSTRACT

Background: His bundle pacing (HBP) and left bundle branch area pacing (LBBAP) emerge as better alternatives to right ventricular apical pacing (RVAP) in patients with bradycardia requiring permanent cardiac pacing. We aimed to compare the clinical outcomes of LBBAP, HBP, and RVAP in Japanese patients with bradycardia. Methods: A total of 424 patients who underwent successful pacemaker implantation (HBP, n = 53; LBBAP, n = 75; and RVAP, n = 296) were retrospectively enrolled in this study. The primary study endpoint was the cumulative incidence of heart failure hospitalization (HFH) during the follow-up. Results: The success rate for implantation was higher in the LBBAP group than in the HBP group (94.9% and 81.5%, respectively). Capture threshold increase >1V during the follow-up occurred in the HBP and RVAP groups (9.4% and 5.1%, respectively), while it did not in the LBBAP group. The cumulative incidence of HFH was significantly lower in the LBBAP group than the RVAP (adjusted hazard ratio, 0.12 [95% confidence interval: 0.02-0.86]; p = .034); it did not differ between the HBP and RVAP groups (adjusted hazard ratio, 0.48 [95% confidence interval: 0.17-1.34]; p = .16). Advanced age, mean percent right ventricular pacing (per 10% increase), left ventricular ejection fraction <50%, and RVAP were associated with HFH. Conclusions: Compared to RVAP and HBP, LBBAP appeared more feasible and effective in patients with bradycardia requiring permanent cardiac pacing.

7.
Jt Dis Relat Surg ; 35(3): 699-705, 2024 Aug 14.
Article in English | MEDLINE | ID: mdl-39189581

ABSTRACT

Dislocations of the fourth and fifth carpometacarpal joints (CMCJs) are rare and often misdiagnosed via radiography. Moreover, treatment strategies have not yet been standardized. Herein, we report a case of chronic dislocations of the fourth and fifth CMCJs with delayed diagnosis and successful treatment via ligament repair. A 29-year-old male patient who was initially diagnosed with contusion at another center following a fall on the stairs was referred to our hospital one month later due to persistent pain and swelling. Fourth and fifth CMCJ dislocations were diagnosed using radiography and computed tomography. Closed reduction attempts were unsuccessful, prompting open reduction. The operative findings included rupture of the dorsal carpometacarpal ligament and hamate cartilage injury. Using two mini anchors, the fourth and fifth dorsal carpometacarpal ligaments were repaired, and Kirschner-wire (K-wire) pinning was performed. The K-wire was extracted after four weeks. At the eight-month follow-up, the only remaining symptom was mild discomfort, and the range of motion and grip strength was fully recovered. Our findings highlight the difficulties in diagnosing CMCJ dislocation and suggest ligament repair as a treatment option for chronic cases of CMCJ dislocation.


Subject(s)
Carpometacarpal Joints , Joint Dislocations , Ligaments, Articular , Humans , Male , Carpometacarpal Joints/injuries , Carpometacarpal Joints/surgery , Carpometacarpal Joints/diagnostic imaging , Adult , Joint Dislocations/surgery , Joint Dislocations/diagnostic imaging , Ligaments, Articular/surgery , Ligaments, Articular/injuries , Chronic Disease , Bone Wires , Treatment Outcome , Range of Motion, Articular , Recovery of Function
8.
Cancers (Basel) ; 16(16)2024 Aug 08.
Article in English | MEDLINE | ID: mdl-39199574

ABSTRACT

Osteosarcoma (OS) is the most common primary bone tumor in children and adolescents. Prognosis is improving with advances in multidisciplinary treatment strategies, but the development of new anticancer agents has not, and improvement in prognosis for patients with pulmonary metastases has stalled. In recent years, the tumor microenvironment (TME) has gained attention as a therapeutic target for cancer. The immune component of OS TME consists mainly of tumor-associated macrophages (TAMs). They exhibit remarkable plasticity, and their phenotype is influenced by the TME. In general, surface markers such as CD68 and CD80 show anti-tumor effects, while CD163 and CD204 show tumor-promoting effects. Surface markers have potential value as diagnostic and prognostic biomarkers. The cytokines and chemokines produced by TAMs promote tumor growth and metastasis. However, the role of TAMs in OS remains unclear to date. In this review, we describe the role of TAMs in OS by focusing on TAM surface markers and the TAM-produced cytokines and chemokines in the TME, and by comparing their behaviors in other carcinomas. We found contrary results from different studies. These findings highlight the urgency for further research in this field to improve the stalled OS prognosis percentages.

9.
Gels ; 9(10)2023 Sep 29.
Article in English | MEDLINE | ID: mdl-37888359

ABSTRACT

Oxidized sucrose (OS) reacts with amino-group-containing polysaccharides, including chitosan, without catalyst, resulting in hydrogels entirely composed of carbohydrates. The presence of imine bonds with low structural stabilities and unreacted aldehydes in the structures of these hydrogels hinder their application as biomaterials. Therefore, herein, the chitosan hydrogels (CTSGs) obtained after the crosslinking of chitosan with OS were reduced using sodium borohydride to convert imine bonds to secondary amines and aldehydes to alcohols. The structures of CTSGs were comprehensively characterized using Fourier transform infrared and 13C nuclear magnetic resonance spectroscopies, and the results implied that the degree of crosslinking (CR) depended on the OS feed amount used during CTSG preparation. The properties of CTSGs were significantly dependent on CR; with an increase in CR, the thermal stabilities and dynamic moduli of CTSGs increased, whereas their swelling properties decreased. CTSGs exhibited antimicrobial properties against the gram-negative bacterium Escherichia coli, and their performances were also dependent on CR. The results indicated the potentials of CTSGs completely based on carbohydrates as antimicrobial hydrogels for various medical and pharmaceutical applications. We believe that this study will contribute to the development of hydrogels for application in the food, medical, and pharmaceutical fields.

10.
Carbohydr Polym ; 322: 121357, 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-37839833

ABSTRACT

Aureobasidium pullulans ß-(1 â†’ 3, 1 â†’ 6)-glucan (APG) has a high degree of ß-(1 â†’ 6)-glucosyl branching and a regular triple helical structure similar to that of schizophyllan. In this study, APG was carboxymethylated to different degrees of substitution (DS = 0.51, 1.0, and 2.0, denoted CMAPG 1-3, respectively) using a heterogeneous reaction. With increasing DS, the triple-helix structure drastically decreased and converted to a random coil structure in CMAPG 3. Further, aqueous solutions of CMAPG changed from pseudoplastic fluids to perfect Newtonian liquids with increasing DS, indicating that the intra- and intermolecular hydrogen bonds had been cleaved by the substituents to form a random coil structure. In addition, APG and CMAPG solutions exhibited scavenging ability against hydroxyl, organic, and sulfate radicals. It was also found that the carboxymethylation of APG drastically enhanced the organic radical scavenging ability. On the basis of the relationship between the DS and radical scavenging ability of the CMAPG samples, we believe hydroxyl and organic radicals were preferably scavenged by the donation of hydrogen atoms from the glucose rings and the methylene moieties of the carboxymethyl groups, respectively. Considering the obtained results, CMAPG and APG are expected to have applications in pharmaceuticals, functional foods, and cosmetics as antioxidant polysaccharides.


Subject(s)
Sizofiran , beta-Glucans , Glucans/chemistry , Antioxidants/pharmacology , Polysaccharides/chemistry , beta-Glucans/chemistry
11.
Gels ; 8(5)2022 May 20.
Article in English | MEDLINE | ID: mdl-35621619

ABSTRACT

To synthesize a biodegradable alternative to spherical polyacrylic acid absorbent resin, spherical hydrogel particles were prepared from carboxymethyl cellulose (CMC) dissolved in an aqueous solution, using ethylene glycol diglycidyl ether (EGDE) as a crosslinking agent. The effect of varying the initial CMC concentration and feed amount of EGDE on the shape, water absorbency, water-holding capacity, and enzyme degradability of the resultant CMC hydrogels was determined. The reaction solution was poured into fluid paraffin, and spherical hydrogel particles were obtained via the shear force from stirring. The shape and diameter of the spherical hydrogel particles in the swollen state depended on the CMC concentration. The spherical hydrogel particles obtained by increasing the amount of EGDE resulted in a decrease in absorbency. Additionally, all the spherical hydrogel particles were degraded by cellulase. Thus, spherical biodegradable hydrogel particles were prepared from CMC, and the particle size and water absorption of the hydrogel could be controlled in the range of 5-18 mm and 30-90 g·g-1 in the swollen state, respectively. As an alternative to conventional superabsorbent polymers, the spherical CMC hydrogels are likely to be useful in industrial and agricultural applications.

12.
Nanomaterials (Basel) ; 12(3)2022 Feb 04.
Article in English | MEDLINE | ID: mdl-35159882

ABSTRACT

Nanofibrillated bacterial cellulose (NFBC), a type of cellulose nanofiber biosynthesized by Gluconacetobacter sp., has extremely long (i.e., high-aspect-ratio) fibers that are expected to be useful as nanofillers for fiber-reinforced composite resins. In this study, we investigated a composite of NFBC and poly(methyl methacrylate) (PMMA), a highly transparent resin, with the aim of improving the mechanical properties of the latter. The abundant hydroxyl groups on the NFBC surface were silylated using 3-(methacryloyloxy)propyltrimethoxysilane (MPTMS), a silane coupling agent bearing a methacryloyl group as the organic functional group. The surface-modified NFBC was homogeneously dispersed in chloroform, mixed with neat PMMA, and converted into PMMA composites using a simple solvent-casting method. The tensile strength and Young's modulus of the composite increased by factors of 1.6 and 1.8, respectively, when only 0.10 wt% of the surface-modified NFBC was added, without sacrificing the maximum elongation rate. In addition, the composite maintained the high transparency of PMMA, highlighting that the addition of MPTMS-modified NFBC easily reinforce PMMA. Furthermore, interactions involving the organic functional groups of MPTMS were found to be very important for reinforcing PMMA.

13.
ACS Omega ; 7(13): 10890-10900, 2022 Apr 05.
Article in English | MEDLINE | ID: mdl-35415377

ABSTRACT

We report that the polymerization of cyclodextrin (CD) with epichlorohydrin (ECH) dramatically increases the binding constant of CD to vanillin, from 55 to 8.4 × 103 M-1, by approximately 100 times, as determined by diffusion ordered spectroscopy (DOSY)-1H NMR. The binding constant increased with an increase of the ECH content of the polymer, although ECH polymers without CDs showed no affinity at all, suggesting that the hydrophobicity of the ECH network outside of CDs helps to enhance the binding. This increased binding constant allows CD-ECH polymers to increase the drug loading ratio, which may be one of the most critical issues for drug delivery systems.

14.
Carbohydr Polym ; 298: 120110, 2022 Dec 15.
Article in English | MEDLINE | ID: mdl-36241327

ABSTRACT

Aqueous sodium hydroxide solution is one of the simplest and most environmentally friendly solvents of cellulose. Regenerated cellulose/glucomannan blends were prepared from an aqueous sodium hydroxide solution, and the mechanical properties and structure of the blends were investigated. In addition, the noodle-shaped blends were sensory evaluated as food materials. The blends exhibited porous structures, which corresponded with high water and oil absorption. The strength and modulus of the blends were markedly low, probably due to the highly porous structure. The viscoelastic measurement indicated that cellulose and glucomannan existed in a rubbery state under wet conditions. The blends had a good oral sensation, probably derived from the remarkable porous structure, high water content, low strength and modulus, and rubbery state in wet conditions. The sensory evaluation suggested that the noodle-shaped blends can be used as a food material with a texture similar to capellini pasta.


Subject(s)
Cellulose , Water , Cellulose/chemistry , Mannans , Sodium Hydroxide/chemistry , Solvents/chemistry , Water/chemistry
15.
Cureus ; 14(7): e27424, 2022 Jul.
Article in English | MEDLINE | ID: mdl-36051722

ABSTRACT

Objective The Graf method is the most widely used ultrasonographic method for evaluating developmental dysplasia of the hip (DDH), and it relies on a set standard plane. However, no previous reports have discussed the detailed anatomical location of the plane. The aim of this study was to evaluate the exact anatomical position of Graf's standard plane in the pelvis and to ascertain the correlation between this position and pelvic morphology in children without abnormal pelvic morphology. Methods We retrospectively assessed the pelvic CT data of 32 children (64 hips) aged three to five years without abnormal pelvic morphology and measured the pelvic winging and acetabular anteversion and coverage. We defined the coronal plane that passed through the center of the bilateral femoral head as plane A. We determined that Graf's standard plane could be approximated by rotating plane A until the outer wall of the ilium was parallel to the sagittal plane, and we defined this as plane A'. AA' was defined as the angle from plane A to plane A' on the sagittal plane. The anterior rotational angle (clockwise, viewing from the right side) was measured as the positive AA'. Moreover, we measured the pelvic rotation, acetabular anteversion, and acetabular coverage and evaluated the correlation between AA' and these morphological parameters. Results The average AA' was -8.27° and AA' had a significant correlation with acetabular anteversion (Spearman's ρ=0.40**, p<0.01). Conclusions We found that Graf's standard plane, as determined by the CT scan, tilts slightly posteriorly. This information may be useful in improving the ease of ultrasonographic examination of DDH.

16.
J Arrhythm ; 38(5): 730-735, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36237858

ABSTRACT

Introduction: The long-term performance of leadless pacemaker (LPM) has not been well evaluated. Methods: Between September 2017 and January 2021, 929 consecutive patients who underwent pacemaker implantation were grouped according to the types of pacemakers: LPM (LPM group, n = 368) and conventional pacemaker (PM group, n = 561). Results: The median follow-up duration was 1.7 years (interquartile range 0.8-2.6 years). Hospitalization rate for heart failure in the LPM group was 9.3%, 15.6%, and 21.6% at 1, 2, 3 years, respectively. The LPM group had a significantly higher adjusted heart failure hospitalization risk than the PM group [hazard ratio (HR) 1.70, 95% confidence interval (CI) 1.09-2.64, p = .01]. More patients with symptomatic bradycardia caused by sinus node dysfunction (SND) in the LPM group (n = 150) were admitted to the hospital for heart failure compared to those in the PM group (n = 219) (HR 2.02, 95%CI 1.04-3.90, p = .03), whereas no significant difference was observed between the two groups in the patients with bradycardia caused by atrial fibrillation (LPM group, n = 71; PM group, n = 18) or atrioventricular block (LPM group, n = 147; PM group, n = 324). Conclusions: Patients who received LPM implantation had greater hospitalization risk for heart failure, compared to those who received conventional pacemaker implantation. The increased risk was mainly attributed to patients with SND.

17.
Carbohydr Res ; 519: 108624, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35749901

ABSTRACT

Glycopolypeptide-immobilized particulates exhibit high binding selectivities and affinities for several analytes. However, to date, the conditions for the synthesis of glycopolypeptide-immobilized particulates have not been optimized and the application of these particulates as carriers for affinity chromatography has not been reported. Accordingly, herein, as a model compound for determining the optimal conditions for the immobilization of an artificial glycopolymer on hexyl-containing hybrid silica particulates (HSPs), the glycopolypeptide poly [GlcNAcß1,4GlcNAc-ß-NHCO-(CH2)5NH-/CH3(CH2)9NH-/γ-PGA] (3) containing multivalent chitobiose moieties and multivalent decyl groups with a γ-polyglutamic acid backbone was synthesized. Immobilization of 3 on HSPs under each condition was evaluated by a lectin-binding assay using wheat germ (Triticum vulgaris) agglutinin (WGA), which is an N-acetylglucosamine-binding lectin. As a result, the optimal immobilization conditions for HSPs at 25 mg/mL were obtained at dimethyl sulfoxide (DMSO) concentration of reaction solvent in the range of 1(DMSO):9(water) to 4(DMSO):6(water) and a compound 3 concentration in the range of 125 nM-1250 nM. Furthermore, the influence of the alkyl group structure introduced into glycopolypeptide for imparting hydrophobicity to it on the immobilization of glycopolypeptide on HSPs was investigated. As a result of comparing three types, poly [GlcNAcß1,4GlcNAc-ß-NHCO-(CH2)5NH-/γ-PGA] (1) with no alkyl group, poly [GlcNAcß1,4GlcNAc-ß-NHCO-(CH2)5NH-/CH3(CH2)4NH-/γ-PGA] (2) with a pentyl group, and 3 with a decyl group, 3 showed the best immobilization efficiency on HSPs. Finally, 1 mg 3-immobilized HSPs prepared under the optimum conditions adsorbed approximately 7.5 µg WGA in a structure-specific manner. We also achieved a simple WGA purification from raw wheat germ extract as a practical example using 3-immobilized HSPs. We believe that in the future, these glycopolypeptide-immobilized particulates will be used not only for the purification of plant lectins, but also as specific adsorbents for various lectins-like substances such as in vivo lectins, pathogenic viruses, and toxin proteins.


Subject(s)
Lectins , Silicon Dioxide , Acetylglucosamine , Dimethyl Sulfoxide , Hydrophobic and Hydrophilic Interactions , Lectins/chemistry , Water , Wheat Germ Agglutinins
18.
Food Chem (Oxf) ; 5: 100119, 2022 Dec 30.
Article in English | MEDLINE | ID: mdl-35845152

ABSTRACT

Bee pollen, a beehive product collected from flowers by honeybees, contains over 250 biological substances, and has attracted increasing attention as a functional food. However, commercial bee pollen products are often multifloral, and samples from different countries vary significantly. There is no universal standard for objective quality assessment of bee pollen based on its chemical composition. Here, we report metabolomic analysis of 11 bee pollen samples from Spain, China, and Australia for quality control. The characteristics of the samples depend on the sucrose, nucleoside, amino acid, and flavanol concentrations. Bee pollen samples from Spain and Australia had higher sucrose and adenosine concentrations, whereas those from China had higher trigonelline, uridine, and cytidine concentrations. Interestingly, acetic acid was only detected in samples from China. These components can be used to identify the country of origin. The obtained profiles of the samples will contribute to universal standard development for bee pollen products.

19.
ACS Omega ; 6(49): 34107-34114, 2021 Dec 14.
Article in English | MEDLINE | ID: mdl-34926958

ABSTRACT

To improve the water dispersibility of cellulose nanofibers without deteriorating the physical properties, it is necessary to develop methods that can selectively modify fiber surfaces. Herein, the reaction conditions for carboxymethylation of the surface of nanofibrillated bacterial cellulose were optimized using chloroacetic acid as an etherification agent. Carboxymethylation in a high-concentration alkaline solution (>5 wt %) in the presence of isopropanol caused the mercerization and carboxymethylation of not only the nanofiber surface but also the cellulose crystals within the nanofiber, resulting in nanofiber swelling and an increase in fiber width. In contrast, with a dilute alkaline aqueous solution (3 wt %), the nanofiber surface was successfully carboxymethylated without changing the inner structure. Furthermore, the morphology was not affected by the carboxymethylation reaction, and no fiber swelling occurred under these reaction conditions. When the substitution reaction proceeded only on the nanofiber surface, the maximum degree of substitution (i.e., the average number of carboxymethyl groups substituted per anhydroglucose residue in cellulose) was 0.091. After surface modification, the nanofibers became more negatively charged, which improved the dispersibility in water through electrostatic repulsion, resulting in a drastic increase in the transparency of the nanofiber dispersion. This method provides a general approach for the surface modification of cellulose nanofibers to increase water dispersibility.

20.
Brain Nerve ; 73(1): 89-93, 2021 Jan.
Article in Japanese | MEDLINE | ID: mdl-33361516

ABSTRACT

Lenticulostriate artery (LSA) aneurysm is relatively rare, and the need for surgical intervention is controversial. Here, we report a case of ruptured LSA aneurysm which was accompanied by familial Mediterranean fever (FMF). A 45-year-old woman with a history of FMF presented with sudden onset of headache and vertigo. Computed tomography revealed hemorrhage in the right caudate nucleus and lateral ventricles. Digital subtraction angiography revealed a fusiform aneurysm (3mm) at the distal site of medial LSA. Observation was selected, and the aneurysm gradually decreased and eventually disappeared on the 105th day from the onset. This was the first report describing an LSA aneurysm associated with FMF. It suggests that such aneurysms could be treated conservatively with close radiological follow-up.


Subject(s)
Aneurysm, Ruptured , Basal Ganglia Cerebrovascular Disease , Familial Mediterranean Fever , Intracranial Aneurysm , Subarachnoid Hemorrhage , Aneurysm, Ruptured/complications , Aneurysm, Ruptured/diagnostic imaging , Aneurysm, Ruptured/surgery , Cerebral Angiography , Female , Humans , Intracranial Aneurysm/complications , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/therapy , Intracranial Hemorrhages , Middle Aged
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