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The production of reactive oxygen species (ROS) during and after the onset of an ischemic stroke induces neuronal cell death and severely damages brain function. Therefore, reducing ROS by administrating antioxidant compounds is a promising approach to improving ischemic symptoms. Alpha-mangostin (α-M) is an antioxidant compound extracted from the pericarp of the mangosteen fruit. Reportedly, α-M decreases neuronal toxicity in primary rat cerebral cortical neurons. In this study, we investigated the neuroprotective activity of α-M in both in vitro and in vivo assays. Pretreatment with α-M inhibited excessive cellular ROS production after oxygen-glucose deprivation/reoxygenation (OGD/R) in vitro using an SH-SY5Y (human neuroblastoma) cell line. In addition, α-M maintained mitochondrial membrane potential and suppressed mitochondrial-specific ROS production induced by OGD/R. Meanwhile, the low bioavailability of α-M due to its poor water solubility has been an insuperable obstruction impeding extensive investigations of the biological functions of α-M and its medical applications. To overcome this problem, we synthesized a cyclodextrin-based nanoparticle (CDNP) that is known to increase the loading efficiency and binding constant of α-M, compared with cyclodextrins themselves. This nano-formulated α-M (α-M/CDNP) was optimized for an in vivo ischemic stroke model. Our results indicated that α-M/CDNP (25 mg/kg/injection) reduced infarct volume and improved neurological behavior (p = 0.036 and p = 0.046, respectively). These in vivo results suggest that α-M appears to cross the blood-brain barrier (BBB) with the help of a nano-formulation with CDNP. Combining an in vitro BBB model and a physicochemical binding assay between α-M and albumin, it is speculated that α-M released from CDNP would interact with albumin during its prolonged circulation in the blood, and the resultant α-M/albumin complex may cross the BBB through the absorptive-mediated transcytosis pathway. These findings suggest the potential clinical application of α-M in ischemic stroke treatment.

Zwitterionic amino acid polymers (ZAPs) exhibit biocompatibility and recognition capability for amino acid transporters (AATs) overexpressed on cancer cells. They are potential cancer-targeting ligands in nanoparticle-based nanomedicines utilized in cancer chemotherapy. Here, a poly(glutamine methacrylate) (pGlnMA)-grafted core-crosslinked particle (pGlnMA-CCP) is prepared through the formation of nanoemulsions stabilized using amphiphilic block copolymers comprising pGlnMA as the hydrophilic block. The chain conformation of the grafted polymer and the particle structure of pGlnMA-CCP are precisely elucidated by dynamic light scattering, X-ray scattering, and transmission electron microscopy. pGlnMA-CCP demonstrates active cellular uptake and deep penetration behaviors for cancer cells and spheroids, respectively, via an AAT-mediated mechanism. The

Organic polymers are materials widely used in our daily lives, such as daily necessities, foods, and medicines. There have been reports recently that cross-linked polyacrylic acid (CL-PAA) can possibly cause serious lung disease. We investigated whether intratracheal instillation of CL-PAA causes pulmonary disorder in rats.Male F344 rats were administered low (0.2 mg/rat) and high (1.0 mg/rat) doses of CL-PAA intratracheally and were dissected 3 days, 1 week, 1 month, 3 months, and 6 months after exposure to examine inflammatory and fibrotic responses in the lungs. Only the high-dose specimens were subjected to ultrasonic dispersion treatment of the administered material.There was a dose-dependent increase in the total cell count, neutrophil count, neutrophil percentage, lactate dehydrogenase (LDH), surfactant protein D (SP-D), cytokine-induced neutrophil chemoattractant (CINC)-1 and CINC-2 values in bronchoalveolar lavage fluid (BALF) from 3 days to at least 3 months after intratracheal administration of CL-PAA. Heme oxygenase-1 (HO-1) in lung tissue was also persistently elevated from 3 days to 6 months after exposure. Alkaline phosphatase (ALP) in BALF was elevated at 3 days and 1 month after exposure only in the high-dose group. Histopathological findings in lung tissue showed inflammatory and fibrotic changes from 3 days after administration, and we observed obvious inflammatory changes for up to 3 months and fibrotic changes for up to 6 months.Intratracheal administration of CL-PAA induced persistent neutrophilic inflammation and fibrosis in the rats' lungs, suggesting that CL-PAA may have inflammogenic and fibrogenic effects.

Calix[4]resorcinarene derivatives such as C-undecylcalix[4]resorcinarene self-assemble into a hexameric capsule-like structure. This structure is expected in any apolar solvent, but we recently found a self-assembled octameric form of resorcinarene in toluene. To understand this unexpected form, we performed small-angle X-ray scattering (SAXS) measurements of the octameric self-assembly. In ab initio shape reconstruction and model fitting of the SAXS profile, a core-shell spherical structure resembling a reverse micelle was found in the octameric self-assembly. The shell and core were composed of alkyl chains and resorcinol moieties, respectively. We also evaluated the temperature dependence of the octameric self-assembly. Above 95 °C, the structure began directly decomposing into unimers, implying the partial cleavage of hydrogen bonds in the octamer core. Meanwhile, below 25 °C, the spherical structure of the octamer partially transformed to a cylindrical structure. This morphological transition could be understood by packing parameter theory, which is often applied to suspected micellar structures.

Poly(2-methoxyethyl acrylate) (PMEA) is known to exhibit excellent thromboresistance, i.e., hardly causing blood-clot formation on its surface. Hence, PMEA and its analogues have been commercially used for blood-contacting materials in medical devices. In this study, we investigated the conformation and solvation state of PMEA in mixtures of tetrahydrofuran (THF) and water with various water volume fractions (ϕwater) by viscosity, sedimentation equilibrium, small-angle X-ray scattering (SAXS), and dielectric relaxation measurements. We also comparatively investigated those of poly[2-(2-methoxyethoxy)ethyl methacrylate] (PMe2MA) and polystyrene (PS). For all of these, THF is a good solvent and water is a nonsolvent or poor solvent. PMe2MA and PMEA show equally good thromboresistance, while PS does not at all. The solution properties of PMe2MA and PMEA were found to be quite different from PS. There are clear attractive interactions (or correlation) between the PMEA chain (or PMe2MA) and the waters in the vicinity of the chain despite their water insolubility. These correlated waters give additional scattering and the angular dependence of SAXS was analyzed in terms of the hydration layer model that has been used in protein solution scattering. The hydration is related to increasing both the chain stiffness and excluded volume. These distinctive properties are likely related to the origin of its good thromboresistance.

Strong directional hydrogen bonds represent a suitable supramolecular force to drive the one-dimensional (1D) aqueous self-assembly of polymeric amphiphiles resulting in cylindrical polymer brushes. However, our understanding of the kinetics in these assembly processes is still limited. We here demonstrate that the obtained morphologies for our recently reported benzene tris-urea and tris-peptide conjugates are strongly pathway-dependent. A controlled transfer from solutions in organic solvents to aqueous environments enabled a rate-dependent formation of kinetically trapped but stable nanostructures ranging from small cylindrical or spherical objects (50 nm) to remarkably large fibers (2 μm). A detailed analysis of the underlying assembly mechanism revealed a cooperative nature despite the steric demands of the polymers. Nucleation is induced by hydrophobic interactions crossing a critical water content, followed by an elongation process due to the strong hydrogen bonds. These findings open an interesting new pathway to control the length of 1D polymer nanostructures.

Block copolymers are well recognized as excellent nanotools for delivering hydrophobic drugs. The formulation of such delivery nanoparticles requires robust characterization and clarification of the critical quality attributes correlating with the safety and efficacy of the drug before applying to regulatory authorities for approval. Static solution scattering from block copolymers is one such technique. This paper first outlines the theoretical background and current models for analyzing this scattering and then presents an overview of our recent studies on block copolymers. Block copolymers are used as nano-tools for delivering hydrophobic drugs. Their formulation requires robust characterization and clarification of the critical quality attributes correlating with the safety and efficacy. Static solution scattering from block copolymers is one such technique. This paper outlines the theoretical background and current models for analyzing this scattering and then presents an overview of our recent studies on block copolymers.

Synthesis of lipid-protein conjugates is one of the significant techniques in drug delivery systems of proteins; however, the intact conjugation of a lipid and protein is yet challenging due to the hydrophobicity of lipid molecules. In order to facilitate easy handling of the lipid moiety in conjugation, we have focused on a microbial transglutaminase (MTG) that can ligate specific lysine (K) and glutamine (Q) residues in lipopeptides and a protein of interest. As MTG substrates, monolipid- and dilipid-fused amphiphilic short lipopeptide substrates (lipid-G3S-RHK or lipid2-KG3S-RHK) were designed. These amphiphilic lipopeptides and a model protein (enhanced green fluorescent protein, EGFP) fused with LLQG (LQ-EGFP) were both water-soluble, and thus lipid-protein conjugates were efficiently obtained through the MTG reaction with a >80% conversion rate of LQ-EGFP even using cholesterol-G3S-RHK. In vitro cell adhesion and in vivo half-life stability of the successfully obtained lipid-protein conjugates were evaluated, showing that the monocholesterol-G3S-RHK modification of a protein gave the highest cell adhesion efficiency and longest half-life time by formation of a stable albumin/lipid-protein complex.

In cancer chemotherapy, core-cross-linked particles (CCPs) are a promising drug carrier due to their high structural stability in an

A β-1,3-glucan binding receptor called Dectin-1 is mainly expressed on antigen-presenting immunocytes. Dectin-1 may be a target molecule for receptor-mediated and active-targeting delivery of drugs to regulate or interfere with the immune system. Therapeutic oligonucleotides are one such drug of interest. To this end, we have been studying the complex of schizophyllan (SPG, one of the linear (1,3)-β-ᴅ-glucan family) with oligonucleotide and its delivery mechanism to the Dectin-1 expressing cells. There are at least six types of human Dectin-1 expressed on the cell surface (designated V-1, V-2, etc.), with V-1 having a complete carbohydrate recognition domain (CRD) and stalk, V-2 having a complete CRD but no stalk, and other variants having an incomplete CRD due to exon skipping. Our previous studies have shown that SPG binds only to V-1 and V-2. By contrast, SPG/oligonucleotide complexes bind both V-1 and V-2 more strongly than SPG itself and show a certain affinity, for other variants. As a continuing work, the present paper discusses the structure and nature of all human Dectin-1 variants expressed on the cellular surface. we found that (1) a new N-linked glycosylation site is present in some variants, (2) the glycosylation of Dectin-1 plays an important role in the fate of Dectin-1 and its localization in the cells, and (3) the glycosylation is related to the amount of ingestion of the complex. The present findings suggest that, in addition to V-1 and V-2, two other variants that are highly expressed at the plasma membrane and stabilized by the glycosylation may also be targets of the complex.

siRNA was complexed with a β-1,3-glucan schizophyllan and intravenously administrated into mice. The complexed siRNA escaped renal excretion and remained in the blood. The monocytes in spleen were ...

Three pathological grading systems advocated by Perzin/Szanto, Spiro, and van Weert are currently used for adenoid cystic carcinoma (AdCC). In these systems, the amount or presence of the solid tumor component in AdCC specimens is an important index. However, the “solid tumor component” has not been well defined. Salivary AdCC cases (N = 195) were collected after a central pathology review. We introduced a novel criterion for solid tumor component, minAmax (minor axis maximum). The largest solid tumor nest in each AdCC case was histologically screened, the maximum oval fitting the solid nest was estimated, and the length of the minor axis of the oval (minAmax) was measured. The prognostic cutoff for the minAmax was determined using training and validation cohorts. All cases were evaluated for the four grading systems, and their prognostic impact and interobserver variability were examined. The cutoff value for the minAmax was set at 0.20 mm. Multivariate prognostic analyses showed the minAmax and van Weert systems to be independent prognostic tools for overall, disease‐free, and distant metastasis‐free survival while the Perzin/Szanto and Spiro systems were selected for overall survival but not for disease‐free or distant metastasis‐free survival. The highest hazard ratio for overall survival (11.9) was obtained with the minAmax system. The reproducibility of the minAmax system (kappa coefficient of 0.81) was scored as very good while those of the other three systems were scored as moderate. In conclusion, the minAmax is a simple, objective, and highly reproducible grading system useful for prognostic stratification for salivary AdCC., The amount or presence of the solid tumor component is an important index for histopathological grading of adenoid cystic carcinoma. However, the “solid tumor component” has not been well defined. We introduced a novel objective criterion for solid tumor component, minAmax (minor axis maximum), and showed that the minAmax is a simple, objective, and highly reproducible grading system useful for prognostic stratification for salivary adenoid cystic carcinoma.

We synthesized lysine- and phenylalanine-based zwitterionic amino acid polymers (ZAPs) and evaluated their recognition capability for amino acid transporters (AATs), which are overexpressed on cancer cells as compared with normal cells. This study clearly demonstrates that ZAPs are internalized via AAT-mediated endocytosis with no cytotoxicity owing to their zwitterionic amino acid nature.

Controlling the particle structure of tumor-targeting nanomedicines in vivo remains challenging but must be achieved to control their in vivo fate and functions. Molecular bottlebrushes (MBs), where brush side chains are densely grafted from a main chain, have recently received attention as building blocks of polymer-based prodrugs because their rigid structure would be expected to demonstrate high structural stability in vivo. Here, we synthesized a poly(methacryloyloxyethyl phosphorylcholine) (pMPC)-grafted molecular bottlebrush (PCMB) conjugated with a cancer drug, doxorubicin (DOX), via an acid-cleavable hydrazone bond. A pMPC-based linear polymer (LP) conjugated with DOX was also prepared for comparison. We confirmed the lack of structural transition in the PCMB between before and after conjugation with DOX using small-angle light and X-ray scattering techniques, whereas the structure of LP was significantly influenced by DOX conjugation and transformed from a random-coil structure to a large agglomerate via hydrophobic interactions among DOXs. Although PCMB-DOX and LP-DOX showed comparable tissue permeability, pharmacokinetics, and ability to accumulate in tumor tissues, the antitumor efficacy of PCMB-DOX was better than that of LP-DOX. This was presumably due to the formation of LP-DOX agglomerates. The diffusion of cleaved DOX would be restricted in the hydrophobic core of the agglomerate, resulting in the DOX release at the tumor site being compromised. In contrast to LP-DOX, DOX release from PCMB-DOX was not compromised after accumulation in tumor tissues because it did not form such an agglomerate, resulting in the strong antitumor effect. We have demonstrated the potential of MBs as building blocks of drug carriers and believe that these findings can contribute to the design of polymer-based nanomedicines.

Alpha-mangostin (MGS) is a natural xanthone compound extracted from mangosteen pericarps. It has great potential as an excellent anticancer agent. However, the extremely low solubility of MGS in water seriously impedes its medical application. Previously, we found that cyclodextrin (CD)-based hyperbranched polymer nanoparticles (CDNPs) solubilize MGS by encapsulating it in the CD cavity and that their binding constants are 100 times higher than those of native CDs. Our findings suggested that CDNPs could be good carriers of MGS. Here, we prepared three types of CDNP from α-, β-, and ɣCDs and compared them in terms of MGS release and in vitro and in vivo anticancer efficacy. βCDNP/MGS demonstrated the greatest anticancer efficacy, while no efficacy was observed for the other CDNPs. MGS release from CDNPs/MGS can be explained by a model in which the slow and rapid modes are connected in series; before release, MGS must shift from the slow to the rapid mode. We assumed that the slow and rapid modes are related to the interior and surface CDs of CDNPs. βCDNP/MGS showed the slowest release in the slow mode. We assume that slow release in the slow mode is essential for MGS retention until the cancerous region is reached. We examined drug release behavior and anticancer efficacy of cyclodextrin-based nanoparticles (CDNPs) containing alpha-mangostin (MGS) in three different type of CDs (α-, β-, and γ-CD). βCDNP containing MGS demonstrated the best anticancer efficacy, while no efficacy was observed for the other CDNPs. Our findings suggested the anticancer efficacy might depend on the drug retention capability in which the interior and surface CDs in the CDNPs relate to the slow and rapid release modes, respectively. We assume the drug retention capability of slow release mode is important for performing the anticancer efficacy.

Oligo-deoxyadenylic acid (dAX) forms a novel 1:2 triple-helix with β-1,3-d-glucan schizophyllan (SPG). We found that dAX meticulously selects the most suitable length of SPG to bind; for example, dA30 only complexes with a short SPG chain having 30, 60, or 90 main-chain glucoses, and they can be easily isolated with each other. This study demonstrated such a novel stoichiometric complex formation by using gel permeation chromatography coupled with multi-angle light scattering and synchrotron small-angle X-ray scattering. These oligo-DNA/polysaccharide complexes can be used as a tool for delivering therapeutic oligonucleotides to immunocytes that express the β-1,3-d-glucan receptors. The present study provides a robust platform technique to characterize them in terms of modern regulatory science of nanomedicines, which is requisite to transfer drug candidates into clinical trial. Our findings are important for characterizing these complexes as well as for providing a new insight into nucleotide and saccharide chemistry.

N-(2-Hydroxypropyl)methacrylamide (HPMA)-based statistical copolymers bearing anticancer drugs have attracted attention for their efficacy in cancer treatments. However, controlling the size and morphology of aggregates of this type of polymer has been challenging and is far from being understood. In this study, small-angle X-ray scattering and asymmetric-flow field-flow fractionation with multiangle light scattering were used to investigate the structure of aggregates formed in aqueous solutions of HPMA-based statistical copolymers of different molecular weights with the model drug pyrene borne in different amounts. The analysis revealed that spherical objects (flower micelles) were formed by the assembly of pyrene moieties in low-molecular-weight copolymers, and the flower micelles connected linearly to form string-of-pearls assemblies (flower necklaces) in high-molecular-weight copolymers. The number of pyrene moieties per polymer chain likely dominates the size and morphology of the copolymer micelles. This study shows how to alter the aggregate structure by changing the molecular weight and composition of copolymers.

By introducing strong directed hydrogen bonds to an amphiphilic polymer, we demonstrate that phase transitions from spherical to cylindrical morphologies in aqueous solutions can significantly be s...

For designing nanoparticles as drug carriers, a covalently crosslinked structure is necessary for the structural stability in vivo. In this study, we prepared core crosslinked nanoparticles through the formation of nanoemulsions stabilized by poly(ethylene glycol) (PEG)-bearing surfactants. The structural characteristics of these particles were carefully evaluated using small-angle scattering techniques including dynamic, static, X-ray, and neutron scattering. The particles demonstrated high stability even in vivo, with the suppression of premature drug release owing to the crosslinked structure. Interestingly, the ability to retain encapsulated molecules was dependent on the molecular weight of PEG in vivo, presumably due to the difference in the crowding density of PEG chains at the outermost surface. This suggests that conferring structural stability via a core crosslinked structure is surely important, but we also need to consider controlling the crowding density of the hydrophilic polymer chains in the particle shell when designing drug carriers.

Owing to the low incidence of adenoid cystic carcinoma (AdCC), reliable survival estimates and prognostic factors remained unclarified. In this multi-institutional retrospective analysis, we collected 192 AdCC cases, and investigated the impact of clinicopathological factors on clinical outcomes of the patients. All AdCC cases were of salivary gland origin and were surgically treated with curative intent. Diagnoses of AdCC were validated by a central pathology review by expert pathologists. The 5-year overall survival (OS) and disease-free survival (DFS) rates were 92.5 and 50.0%, respectively. Treatment failure occurred in 89 patients (46%) with the distant failures in 65 (34%). Multivariate analysis indicated that pN2 and a pathologically positive surgical margin were independent prognostic factors for both OS and DFS. Histological grade III was an independent prognostic factor for OS. A primary site in the submandibular gland, pT3/4, pN1, and histological grade II were independent prognostic factors for DFS. Postoperative radiation therapy (PORT) improved the locoregional control (LRC) rate. Prophylactic neck dissection was not associated with a better OS or better LRC among patients with cN0. Facial nerve dissection did not improve clinical outcomes in parotid AdCC cases without facial nerve palsy. A higher TN classification, a pathologically positive surgical margin, and a higher histological grade were associated with a lower OS. PORT improved LRC rates but neck dissection failed to improve clinical outcomes in patients with cN0. As the distant metastasis was frequent, effective systemic therapy is imperative to improve the survival of AdCC patients.

In 1997, a study based on X-ray crystallography revealed that resorcinarenes adopt a hexameric capsule-like structure. The function of resorcinarenes has been discussed on the basis of this structure; however, our recent study showed that the hexamer may be only one of resorcinarenes' polymorphic members. Here, we present the solvent dependence of the aggregation number of

Ureido-modified poly(l-citrulline) (l-ornithine-co-l-citrulline denoted by PlOC) shows UCST-type phase separation behavior even under physiologically relevant conditions, which forms an α-helix structure above its phase separation temperature (Tp) but transforms into a solid-like aggregation composed of regular hexagonal packed cylinders below the Tp. This morphological transformation is characteristic of the phase separation behavior, but the mechanism behind it has remained incompletely understood. Here, we studied the phase separation behavior using small-angle X-ray scattering (SAXS) measurements. To analyze the SAXS data, we employed the modified unified model proposed previously, which decomposes the scattering profile into each structural element, such as the α-helices and their aggregation formed via hydrogen-bonding interactions between the ureido groups. The aggregation level is dependent on the temperature (T) and grouped into three classes: (1) mass-fractal aggregation composed of the α-helix (T > Tp), (2) spherical aggregation composed of the hexagonal packed cylinder (T < Tp), and (3) micro-order agglomeration formed by mutual fusion of the spherical aggregation, which appears as a solid-like aggregation. The SAXS analysis suggested that the transformation from the dispersed state as the α-helix to the agglomeration containing hierarchical structures occurs in a stepwise manner when the temperature falls below the Tp, which might also be transition behavior similar to the process of protein folding through folding intermediates.

Biocompatible polymers possessing antifouling properties for biomolecules are necessary to be combined with nanoparticles for cancer chemotherapy to improve their retention in blood and subsequent tumor accumulation. However, these properties simultaneously lead to poor affinity to cells, and low tumor tissue permeability subsequently, which is one of the major barriers in achieving efficient anticancer efficacy. To address this, we try to elucidate the tumor permeability of nanoparticles using molecular bottlebrushes (MBs) as model polymeric nanoparticles composed of various biocompatible polymers. An MB comprising nonionic poly[(ethylene glycol) methyl ether methacrylate] (PEGMA) shows no tumor permeability at all, whereas zwitterionic MBs composed of poly(phosphobetaine methacrylate), poly(sulfobetaine methacrylate), or poly(carboxybetaine methacrylate) penetrate deeply into tumor tissues. The carboxybetaine-based MBs showed an efficient cellular uptake into cancer cells while the other MBs did not, which enable them to penetrate into tumor tissues via the transcytosis pathway. Additionally, their permeability is based on intercellular or intracellular pathways, which might be related to the zwitterionic betaine properties that recognize protein transporters on cancer cells. Surprisingly, incorporating only 10 mol % of the zwitterionic betaine polymers into PEGMA-based MBs significantly enhances their tissue permeability. This platform technology enables us to redesign the PEG-based nanoparticles developed for cancer chemotherapy in clinical applications.

Antisense oligonucleotides (AS-ODNs) attach to mRNA in a sequence specific manner and eventually inhibit protein expression. The target mRNA locates in cytoplasm; therefore AS-ODNs must be delivere...

An amphiphilic diblock copolymer (PChM-PNIPAM), composed of poly(cholesteryl 6-methacryloyloxy hexanoate) (PChM) and poly(N-isopropyl acrylamide) (PNIPAM) blocks, was prepared via reversible addition–fragmentation chain transfer radical polymerization. The PChM and PNIPAM blocks exhibited liquid crystalline behavior and a lower critical solution temperature (LCST), respectively. PChM-PNIPAM formed water-soluble polymer micelles in water below the LCST because of hydrophobic interactions of the PChM blocks. The PChM and PNIPAM blocks formed the core and hydrophilic shell of the micelles, respectively. With increasing temperature, the molecular motion of the pendant cholesteryl groups increased, and a liquid crystalline phase transition occurred from an amorphous state in the core. With further increases in temperature, the PNIPAM block in the shell exhibited the LCST and dehydrated. Hydrophobic interactions of the PNIPAM shells resulted in inter-micellar aggregation above the LCST.

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 × 10

We found dramatically increased binding between cyclodextrins (CDs) and alpha-mangostin (MGS) when CDs were incorporated into nanoparticles with polymerized epichlorohydrin. In this study, based on...

Background To assess the role of a central pathology review in the diagnosis of salivary gland adenoid cystic carcinoma (AdCC). Methods Surgically resected salivary gland tumors diagnosed as AdCC (n = 219) in 15 reference hospitals in Japan were subjected to a retrospective pathological re-evaluation. Results After the review, the AdCC diagnosis was revised in 21/219 cases (9.6%). The six benign tumors (2.7%) comprised five basal cell adenomas and one pleomorphic adenoma, and among these six patients, three received postoperative radiotherapy. The remaining 15 malignant tumors (6.8%) comprised nine basal cell adenocarcinomas and six other carcinomas. All revised basal cell adenoma/adenocarcinoma cases were of rare cribriform variants. Conclusions A significant proportion of AdCC pathology reports were revised after the central pathology review. It should be emphasized that the greatest attention should be paid in differentiating AdCC from cribriform variant basal cell adenoma/adenocarcinoma, which is very rare in salivary gland tumors.

Reinforcement of the in vivo structural stability of polymer-based nanoparticles such as polymeric micelles has been achieved via covalently crosslinked structures. Herein, we report new core crosslinked nanoparticles prepared via an o/w nanoemulsion composed of difunctional polymerizable oil monomers stabilized by a poly(ethylene glycol) (PEG)-bearing surfactant. The obtained PEG-tethered core crosslinked nanoparticles are named furry nanoparticles (f-NPs). The f-NPs’ structure was evaluated using light scattering (LS; both static SLS and dynamic DLS), small-angle X-ray scattering, and transmission electron microscopy. The f-NPs’ size could be easily controlled by changing the amount of oil monomer, which also affected dye loading and releasing behavior. Employing a disulfide-based oil monomer, we could endow the f-NPs with sensitivity to reduction, demonstrating destabilization in a reducing environment with a high glutathione level matching that in tumors. The structural stability of f-NPs in vivo was very high compared with that of a micellar system, resulting in prolonged circulation in the bloodstream. Interestingly, the in vivo stability might depend on the crowding density of PEG chains at the outermost surface, even though the structural stability was guaranteed by the crosslinked structure. This study demonstrates the promising synthesis of core crosslinked nanoparticles and their potential as drug carriers.

Polymeric micelles have been extensively studied as nanoscale drug carriers. Knowing how the encapsulation of drugs alters the micellar structure is one of the most important issues for the biomedical application of amphiphilic block copolymers. However, little is known so far about the structural changes that micelles undergo upon loading with water-insoluble guests. Herein, we investigate the micellar morphology of ABC triblock terpolymers after loading with various water-insoluble molecules (naphthalene and its derivatives as drug-equivalent model molecules). The triblock terpolymer features a poly(ethylene oxide) (PEO) block, a poly(allyl glycidyl ether) segment which has been functionalized with carboxylic acid moieties (PAGECOOH), and poly(tert-butyl glycidyl ether) (PtBGE) as a hydrophobic block. Structural analysis by small-angle X-ray scattering (SAXS) and cryogenic and conventional transmission electron microscopy (TEM) found that a morphological transition from spherical micelles to vesicles (polymersomes) was induced by loading the guest molecules at pH 4, whilst the spherical and prolate morphologies remained unchanged upon loading at pH 6 and 8. This study highlights the dynamics and morphological changes of polymeric micelles upon loading with guest molecules.

Upon extending a hydrophobic polymer chain from the end of a preceding hydrophilic chain in aqueous solutions, the resultant block copolymers may eventually undergo self-assembly. Further chain propagation continues in the newly formed hydrophobic polymer rich domain. This process is often referred to as polymerization-induced self-assembly (PISA). Its kinetics are determined by the polymerization and the micelle formation/growth, which may influence each other, possibly leading to a highly complex process of structural development. In this study, we examined PISA in aqueous solution on the reversible addition fragmentation chain transfer (RAFT) dispersion polymerization of poly(N-acryloylmorpholine)-b-poly(N-acryloylthiomorpholine). Using in situ small-angle X-ray scattering (SAXS) and nuclear magnetic resonance spectroscopy (NMR), the polymerization and micelle formation were observed. In the analysis, because the time scale of the micelle formation/growth is much shorter than that of the polymerization, the polymerization and micelle fomarion/growth can be decoupled. Thus, these were separately analyzed in depth, and a combination of the kinetics of RAFT polymerization and the simple scaling theory of the micellar structures can quantitatively describe the overall micellar structural development during PISA. This study provides an unprecedented insight into the processes underlying PISA and deepens our quantitative understanding of it.

α-Mangostin (MGS), an anti-cancer compound, is a xanthone derivative and is extracted from the pericarps of mangosteen. MGS exhibits a variety of bioactivities, such as antioxidant, cytotoxic, anti-inflammatory, and antibacterial effects, as well as anticancer activity. However, MGS has not been approved for clinical use because of its poor bioavailability. There have been many efforts to solve this problem by use of drug carriers. Cyclodextrins (CDs) are well known as nontoxic and biodegradable drug carriers and can encapsulate MGS. In this study, we prepared CD-based nanoparticles (CDNPs) by a polyaddition reaction using epichlorohydrin and characterized them by dynamic light scattering and static light scattering coupled with fractionation. The encapsulation of MGS into CDNPs was examined, and we found that the loading ratio of MGS for CDNPs is much higher than that for CDs themselves. The cytotoxicity of the CDNP/MGS complex was examined, indicating the potential of CDNP as a carrier of MGS. In this study, we synthesized and characterized cyclodextrin-based nanoparticles (CDNPs) by polyaddition reactions using epichlorohydrin and three different type of CDs (α-, β-, and γ-CD). We found that cyclodextrin tended to cover surface of our nanoparticles; while epichlorohydrin network enlarged when weight ratio of epichlorohydrin/cyclodextrin increased. Our CDNPs demonstrated a very high loading ratio against α-mangostin (MGS), and getting close to 1:1 ratio.

We demonstrated that polypod-like structured DNA, composed of 3-8 kinds of oligodeoxynucleotides (ODNs), exhibit accelerated cellular uptake depending on their structural properties. The biological activities, including immunostimulation and unwanted adverse effects of ODNs depend on their sequences. Therefore, as the number of different types of ODNs within a polypod-like structured DNA increases, the possible risks and concerns regarding its future clinical applications also increase. To minimize this risk and to explore the relationship between structural properties and cellular uptake, we designed Tet(id12), a tetrapod-like structured DNA with 12 identical palindrome sequences in the center of ODNs, and compared it with other tetrapod-like structures without palindrome sequences, symmetric Tet(sym) and asymmetric Tet(asym12). The thermal stability analysis of Tet(id12) revealed a two-step dissociation process. Polyacrylamide gel electrophoresis, small-angle X-ray scattering profile, and the Guinier plot also revealed that the conformation of Tet(id12) was close to that of Tet(sym). No significant differences were observed between Tet(id12) and others in terms of cellular uptake. These results indicate that ODNs with palindrome sequences can be used to design polypod-like structured DNAs without significant changes to their physicochemical and biological properties, although their thermal stability is somewhat different from the ones without palindrome sequences.