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Silty mudstone is highly susceptible to the influence of hot and humid environments, leading to the deterioration of its mechanical properties presenting a geohazard and even resulting in geological disasters. Accurately characterizing the effects of bedding and water–rock interaction on the mechanical behaviour of silty mudstone is a crucial prerequisite for the protection and reinforcement of silty mudstone slopes. To this end, uniaxial compression tests and Brazilian splitting tests were conducted to examine the mechanical properties of bedded silty mudstone. Based on the test results, the effects of bedding angle and soaking time on mechanical properties such as tensile strength, uniaxial compressive strength and elastic modulus of bedded silty mudstone were revealed. The test results showed that the tensile strength increased exponentially with increasing bedding angle. The observed split failure patterns of bedded silty mudstone encompassed splitting–pulling damage, shear damage and splitting damage. The uniaxial compressive strength of silty mudstone exhibited a U-shaped variation with an increase in bedding angle. The specimen with a bedding angle of 45° had the lowest uniaxial compressive strength at 7.64 MPa. Furthermore, the elastic modulus of silty mudstone was positively correlated with the bedding angle. The failure patterns of bedded silty mudstone under uniaxial compression included splitting-tension damage, shear-slip damage and splitting-shear damage. The saturated tensile strength, uniaxial compressive strength and elastic modulus of bedded silty mudstone exhibited an exponential decrease with increasing soaking time. The test data confirmed the applicability of the Jaeger equation to the uniaxial compressive strength of bedded silty mudstone. Subsequently, a modified Hoek–Brown failure criterion was derived by combining fracture mechanics theory and test results and introducing a softening factor. The parameters A, D and m in the above failure criterion decreased exponentially with increasing soaking time and an empirical Hoek–Brown failure criterion considering the soaking time was established. Compared with previous theoretical models, this model is more adaptable to the actual engineering situation, which results in more accurate calculations. [ABSTRACT FROM AUTHOR]

Cancer stem cells (CSCs) are considered responsible for tumor initiation and chemoresistance. This study was aimed to investigate the possibility of targeting head neck squamous cell carcinoma (HNSCC) by NOTCH1 pathway inhibition and explore the synergistic effect of combining NOTCH inhibition with conventional chemotherapy. NOTCH1/HES1 elevation was found in human HNSCC, especially in tissue post chemotherapy and lymph node metastasis, which is correlated with CSCs markers. NOTCH1 inhibitor DAPT (GSI-IX) significantly reduces CSCs population and tumor self-renewal ability in vitro and in vivo. Flow cytometry analysis showed that NOTCH1 inhibition reduces CSCs frequency either alone or in combination with chemotherapeutic agents, namely, cisplatin, docetaxel, and 5-fluorouracil. The combined strategy of NOTCH1 blockade and chemotherapy synergistically attenuated chemotherapy-enriched CSC population, promising a potential therapeutic exploitation in future clinical trial.

Immunotherapy with immune checkpoint molecule-specific monoclonal antibody have obtained encouraging results from preclinical studies and clinical trials, which promoted us to explore whether this kind of immunotherapy could be applicable to head and neck squamous cell carcinoma (HNSCC). Lymphocyte activation gene-3 (LAG-3) is an immune checkpoint control protein that negatively regulates T cells and immune response. Here, using the human tissue samples, we report these findings that LAG-3 is overexpressed on tumor-infiltrating lymphocytes (TILs; p < 0.001) and its overexpression correlates with the high pathological grades, lager tumor size and positive lymph node status in human primary HNSCC. Survival analysis identifies LAG-3 as a prognostic factor independent of tumor size and pathological grades for primary HNSCC patients with negative lymph node status (p = 0.014). Study in immunocompetent genetically defined HNSCC mouse model reports that LAG-3 is upregulated on CD4+ T cells, CD8+ T cells and CD4+Foxp3+ regulatory T cells (Tregs). In vivo study, administration of LAG-3-specific antibody retards tumor growth in a way associated with enhanced systemic antitumor response by potentiating the antitumor response of CD8+ T cells and decreasing the population of immunosuppressive cells. Taken together, our results offer a preclinical proof supporting the immunomodulatory effects of LAG-3 and suggest a potential therapeutic target of immunotherapy for HNSCC.

Myeloid-derived suppressor cells (MDSCs) and tumor associated macrophages (TAMs) play key roles in the tumor immune suppressive network and tumor progression. However, precise roles of programmed death-1 (PD-1) in immunological functions of MDSCs and TAMs in head and neck squamous cell carcinoma (HNSCC) have not been clearly elucidated. In the present study, we show that PD-1 and PD-L1 levels were significantly higher in human HNSCC specimen than in normal oral mucosa. MDSCs and TAMs were characterized in mice and human HNSCC specimen, correlated well with PD-1 and PD-L1 expression. αPD-1 treatment was well tolerated and significantly reduced tumor growth in the HNSCC mouse model along with significant reduction in MDSCs and TAMs in immune organs and tumors. Molecular analysis suggests a reduction in the CD47/SIRPα pathway by PD-1 blockade, which regulates MDSCs, TAMs, dendritic cell as well as effector T cells. Hence, these data identify that PD-1/PD-L1 axis is significantly increased in human and mouse HNSCC. Adoptive αPD-1 immunotherapy may provide a novel therapeutic approach to modulate the micro- and macro-environment in HNSCC.

Bacteria are the causative agents of various infectious diseases; however, the anti‐tumor effect of some bacterial species has attracted the attention of many scientists. The human oral cavity is inhabited by abundant and diverse bacterial communities and some of these bacterial communities could play a role in tumor suppression. Therefore, it is crucial to find oral bacterial species that show anti‐tumor activity on oral cancers. In the present study, we found that a high abundance of Porphyromonas gingivalis, an anaerobic periodontal pathogen, in the tumor microenvironment (TME) was positively associated with the longer survival of patients with oral squamous cell carcinoma (OSCC). An in vitro assay confirmed that P. gingivalis accelerated the death of OSCC cells by inducing cell cycle arrest at the G2/M phase, thus exerting its anti‐tumor effect. We also found that P. gingivalis significantly decreased tumor growth in a 4‐nitroquinoline‐1‐oxide‐induced in situ OSCC mouse model. The transcriptomics data demonstrated that P. gingivalis suppressed the biosynthesis of mucin O‐glycan and other O‐glycans, as well as the expression of chemokines. Validation experiments further confirmed the downregulation of mucin‐1 (MUC1) and C‐X‐C motif chemokine 17 (CXCL17) expression by P. gingivalis treatment. Flow cytometry analysis showed that P. gingivalis successfully reversed the immunosuppressive TME, thereby suppressing OSCC growth. In summary, the findings of the present study indicated that the rational use of P. gingivalis could serve as a promising therapeutic strategy for OSCC. [ABSTRACT FROM AUTHOR]

Objectives: Our study elucidates the prognostic role of cluster of differentiation (CD) 24 expression in oral squamous cell carcinoma (OSCC) and determines whether targeting CD24 enhances the anti‐tumor immune response by inhibiting tumor‐associated macrophages (TAMs). Materials and Methods: The expression of CD24 and CD68 was analyzed immunohistochemically via tissue microarrays constructed using 56 cohorts of patients with OSCC and 20 control specimens. Further, CD24 was inhibited in an allograft squamous cell carcinoma (SCC) related mouse model with CD24mAb to determine the tumor volume and weight. Changes in immune cells such as TAMs and T cells in the tumor microenvironment (TME) were analyzed by Flow cytometry. The expression of CD4, CD8, and Ki67 was analyzed via immunohistochemistry. The inhibition of CD24 was confirmed by Western blot and immunohistochemistry. Results: CD24 was overexpressed in OSCC. High expression of CD24 indicated poor survival in patients with OSCC (p = 0.0334). CD24 expression was significantly correlated with CD68 (p = 0.0424). The inhibition of CD24 delayed tumor growth in vivo. A decrease in TAMs number and an increase in T cell number were confirmed, while the ability of tumor proliferation was impaired. Conclusion: Targeting CD24 could enhance anti‐tumor immune response by inhibiting TAMs. [ABSTRACT FROM AUTHOR]

Oral disease, as a class of diseases with very high morbidity, brings great physical and mental damage to people worldwide. The increasing burden and strain on individuals and society make oral diseases an urgent global health problem. Since the treatment of almost all oral diseases relies on materials, the rapid development of advanced materials and technologies has also promoted innovations in the treatment methods and strategies of oral diseases. In this review, we systematically summarized the application strategies in advanced materials and technologies for oral diseases according to the etiology of the diseases and the comparison of new and old materials. Finally, the challenges and directions of future development for advanced materials and technologies in the treatment of oral diseases were refined. This review will guide the fundamental research and clinical translation of oral diseases for practitioners of oral medicine. [ABSTRACT FROM AUTHOR]

Accumulated evidence indicates that immune cell populations play pivotal roles in the process of tumor initiation, progression, recurrence, metastasis, and immune escape. Ferroptosis is a form of regulating cell death in the nexus between metabolism, redox biology, and human health. Ferroptosis is considered as a vital important event in HNSCC, but the underling mechanism of regulating immune cell populations remains poorly understood. Our tissue microarray study showed that patients with high expression of GPX4 were related to poor survival. Moreover, the expression of GPX4 has been negatively associated with immunogenic cell death‐related protein calreticulin in HNSCC tissue cohort. Further, RSL3 was used to induce ferroptosis in HNSCC xenograft of C3H/He mouse. We found that the occurrence of ferroptosis had significantly reduced the number of myeloid‐derived suppressor cells (MDSCs) and tumor‐associated M2‐like macrophages (M2 TAMs) in tumor microenvironment. Meanwhile, the tumor‐infiltrating CD4+ and CD8+ T cells were increased. And the calreticulin and HMGB1 may be potential candidate proteins improving the immunosuppressive tumor microenvironment. Taken together, our project suggests that ferroptosis can promote anti‐tumor immune response by reversing immunosuppressive microenvironment, indicating that ferroptosis inducer is a promising therapeutic strategy in HNSCC. [ABSTRACT FROM AUTHOR]

As a typical hallmark of solid tumors, hypoxia affects the effects of tumor radiotherapy, chemotherapy, and photodynamic therapy. Therefore, targeting the hypoxic tumor microenvironment (TME) is a promising treatment strategy for cancer therapy. Here, we prepared an Albumin Human Serum (HSA)-coated perfluorocarbon (PFC) carrying oxygen (PFC@O2) to minimize OSCC hypoxia. The results showed that PFC@O2 significantly downregulated the expression of HIF-1α and the number of M2-like macrophages in vitro. Furthermore, PFC@O2 effectively inhibited the growth of oral squamous cell carcinoma (OSCC) and reduced the proportion of negative immunoregulatory cells, including myeloid-derived suppressor cells (MDSCs) and M2-like macrophages of TME in a 4-nitroquinoline N-oxide (4NQO)-induced mouse model. Conversely, the infiltration of CD4+ and CD8+ T cells was significantly increased in TME, suggesting that the anti-tumor immune response was enhanced. However, we also found that hypoxia-relative genes expression was positively correlated with CD68+/CD163+ TAMs in human tissue specimens. In summary, PFC@O2 could effectively inhibit the progression of OSCC by alleviating hypoxia, which provides a practical basis for gas therapy and gas synergistic therapy for OSCC. [ABSTRACT FROM AUTHOR]

The urothermal reactions of Co(II)/Zn(II) salts with the diverse carboxylic acid and 1,3,5,-tris(1-imidazolyl)benzene(tib) ligands afforded three novel MOFs, namely, [Co3(tib)2(abdc)2(ox)]2·6H2O (1), [Co3O(tib)(abdc)2(DMI)]·2DMI·2H2O (2) and [Zn3I2(tib)2(napdc)2]·2DMI·2H2O (3), (H2abdc = 5-amino-1,3-benzenedicarboxylate, H2napdc = 1,4-naphthalene dicarboxylic acid and DMI = 1,3-dimethyl-2-imidazolidinone). In compounds 1 and 2, the Co(II) atoms are connected by polycarboxylate ligands to form two-dimensional (2D) layers that are pillared by tib ligands leading to the formation of 3D porous frameworks. In compound 3, the Zn(II) atoms are linked by tib ligands to form one-dimensional ribbon-like chains which are further connected by polycarboxylate ligands, making a 3D framework possible. Compound 1 can selectively adsorb unsaturated hydrocarbon molecules (C2H2 and C2H4) and saturated hydrocarbon molecules (C2H6 and CH4). Specifically, compound 1 has high IAST selectivity for acetylene and methane (0.50 : 0.50, v/v) at 273 K and 1 bar. DFT calculations reveal that the π-conjugated hexagonal carbon ring may be the primary adsorption site because there are π–π interactions between the unsaturated hydrocarbon molecules (C2H2 and C2H4) and the π-conjugated hexagonal carbon ring in the framework of compound 1. [ABSTRACT FROM AUTHOR]

Herein, we report that genetically programmable fusion cellular vesicles (Fus‐CVs) displaying high‐affinity SIRPα variants and PD‐1 can activate potent antitumor immunity through both innate and adaptive immune effectors. Dual‐blockade of CD47 and PD‐L1 with Fus‐CVs significantly increases the phagocytosis of cancer cells by macrophages, promotes antigen presentation, and activates antitumor T‐cell immunity. Moreover, the bispecific targeting design of Fus‐CVs ensures better targeting on tumor cells, but less on other cells, which reduces systemic side effects and enhances therapeutic efficacies. In malignant melanoma and mammary carcinoma models, we demonstrate that Fus‐CVs significantly improve overall survival of model animals by inhibiting post‐surgery tumor recurrence and metastasis. The Fus‐CVs are suitable for protein display by genetic engineering. These advantages, integrated with other unique properties inherited from source cells, make Fus‐CVs an attractive platform for multi‐targeting immune checkpoint blockade therapy. [ABSTRACT FROM AUTHOR]

Background: This study aims to investigate the characteristic role of inhibitory receptor leukocyte‐associated immunoglobulin‐like receptor 1 (LAIR‐1) in oral squamous cell carcinoma (OSCC). Methods: The expressions of LAIR‐1 and other immune‐related molecules were detected in a human OSCC tissue microarray. LAIR‐1 expression difference among different clinicopathological parameters was analyzed. The correlations of LAIR‐1 with several immune‐related markers were assessed. Results: Compared with dysplasia and oral mucosa, the expression of LAIR‐1 was significantly upregulated in the stroma of OSCC, and its overexpression was correlated with advanced pathological grade. Overexpression of LAIR‐1 was significantly associated with tumor‐associated macrophage and myeloid‐derived suppressor cell markers (CD68, CD163; CD33, CD11b), indoleamine 2,3‐dioxygenase (IDO) and two immune checkpoints (B7‐H3 and VISTA). Conclusions: Overexpression of LAIR‐1 was associated with advanced pathological grade and correlated with immune suppressive features in OSCC. Further studies are required to identify the specific immunological role of LAIR‐1. [ABSTRACT FROM AUTHOR]

The adenosine‐induced immunosuppression hampers the immune response toward tumor cells and facilitates the tumor cells to evade immunosurveillance. CD73, an ecto‐5‐nucleotidase, is the ectoenzyme dephosphorylating extracellular AMP to adenosine. Here, using immunocompetent transgenic head and neck squamous cell carcinoma (HNSCC) mouse model, immune profiling showed high expression of CD73 on CD4+ and CD8+ T cells was associated with an “exhausted” phenotype. Further, treatment with anti‐CD73 monoclonal antibody (mAb) significantly blunted the tumor growth in the mouse model, and the blockade of CD73 reversed the “exhausted” phenotype of CD4+ and CD8+ T cells through downregulation of total expression of PD‐1 and CTLA‐4 on T cells. Whereas the population of CD4+CD73hi/CD8+CD73hi T cells expressed higher CTLA‐4 and PD‐1 as compared to untreated controls. In addition, the human tissue microarrays showed the expression of CD73 is upregulated on tumor infiltrating immune cells in patients with primary HNSCC. Moreover, CD73 expression is an independent prognostic factor for poor outcome in our cohort of HNSCC patients. Altogether, these findings highlight the immunoregulatory role of CD73 in the development of HNSCC and we propose that CD73 may prove to be a promising immunotherapeutic target for the treatment of HNSCC. [ABSTRACT FROM AUTHOR]

Abstract: A major challenge for traditional cancer therapy, including surgical resection, chemoradiotherapy, and immunotherapy, is how to induce tumor cell death and leverage the host immune system at the same time. Here, a myeloid‐derived suppressor cell (MDSC) membrane‐coated iron oxide magnetic nanoparticle (MNP@MDSC) to overcome this conundrum for cancer therapy is developed. In this study, MNP@MDSC demonstrates its superior performance in immune evasion, active tumor‐targeting, magnetic resonance imaging, and photothermal therapy (PTT)‐induced tumor killing. Compared with red blood cell membrane‐coated nanoparticles (MNPs@RBC) or naked MNPs, MNP@MDSCs are much more effective in active tumor‐targeting, a beneficial property afforded by coating MNP with membranes from naturally occurring MDSC, thus converting the MNP into “smart” agents that like to accumulate in tumors as the source MDSCs. Once targeted to the tumor microenvironment, MNPs@MDSC can act as a PTT agents for enhanced antitumor response by inducing immunogenic cell death, reprogramming the tumor infiltrating macrophages, and reducing the tumor's metabolic activity. These benefits, in combination with the excellent biocompatibility and pharmacological kinetics characteristics, make MNP@MDSC a promising, multimodal agent for cancer theranostics. [ABSTRACT FROM AUTHOR]

Biomimetic cell-membrane-camouflaged nanoparticles with desirable features have been widely used for various biomedical applications. However, the current research focuses on single cell membrane coating and using multiple cell membranes for nanoparticle functionalization is still challenging. In this work, platelet (PLT) and leukocyte (WBC) membranes are fused, PLT-WBC hybrid membranes are coated onto magnetic beads, and then their surface is modified with specific antibodies. The resulting PLT-WBC hybrid membrane-coated immunomagnetic beads (HM-IMBs) inherit enhanced cancer cell binding ability from PLTs and reduce homologous WBC interaction from WBCs, and are further used for highly efficient and highly specific isolation of circulating tumor cells (CTCs). By using spiked blood samples, it is found that, compared with commercial IMBs, the cell separation efficiency of HM-IMBs is improved to 91.77% from 66.68% and the cell purity is improved to 96.98% from 66.53%. Furthermore, by using the HM-IMBs, highly pure CTCs are successfully identified in 19 out of 20 clinical blood samples collected from breast cancer patients. Finally, the robustness of HM-IMBs is verified in downstream CTC analysis such as the detection of PIK3CA gene mutations. It is anticipated that this novel hybrid membrane coating strategy will open new possibilities for overcoming the limitations of current theranostic platforms. [ABSTRACT FROM AUTHOR]

SRC family kinases (SFKs), a group of nonreceptor tyrosine kinases, modulate multiple cellular functions, such as cell proliferation, differentiation and metabolism. SFKs display aberrant activity in progressive stages of human cancers. However, the precise role of SFKs in the head and neck squamous cell carcinoma (HNSCC) signaling network is far from clear. In this study, we found that the inhibition of SFKs activity by dasatinib effectively reduced the tumor size and population of MDSCs in the HNSCC mouse model. Molecular analysis indicates that phosphorylation of LYN, rather than SRC, was inhibited by dasatinib treatment. Next, we analyzed LYN expression by immunostaining and found that it was overexpressed in the human HNSCC specimens. Moreover, LYN expression in stromal cells positively correlated with myeloid-derived suppressor cells (MDSCs) makers CD11b and CD33 in human HNSCC. The dual positive expression of LYN in epithelial and stromal cells (EPI+ SRT+) was associated with unfavorable overall survival of HNSCC patients. These findings indicate that SFKs may be a potential target for an effective immunotherapy of HNSCC by decreasing MDSCs and moreover, LYN will have an impact on such therapeutic strategy. [ABSTRACT FROM AUTHOR]

T-cell immunoglobulin mucin 3 ( TIM3) contributes to immune suppression during progression of many cancers, but the precise role of TIM3 in head and neck squamous cell carcinoma ( HNSCC) is not clearly understood. In this study, we report that TIM3 expression was significantly up-regulated in patients with HNSCC and associated with lymph node metastasis. Additionally, TIM3 expression was increased in patients with recurrent HNSCC and patients with preradiotherapy or prechemotherapy. We also characterized CD8+ T cells and CD11b+ CD33+ myeloid-derived suppressor cells ( MDSCs) in human HNSCC, and found that their expression was positively correlated with TIM3 expression. To determine the underlying mechanism of TIM3 in immune response during HNSCC progression, we utilized the Tgfbr1/Pten 2c KO HNSCC mouse model with TIM3 overexpression. Treatment with anti- TIM3 monoclonal antibody effectively suppressed tumor growth through restoring effector T-cell function by targeting CD4+ TIM3+ cells and CD8+ TIM3+ cells and decreasing MDSCs. Our findings demonstrate TIM3 expression in patients with HNSCC and suggest anti- TIM3 immunotherapy as a novel therapeutic approach for effective treatment of HNSCC. [ABSTRACT FROM AUTHOR]

Angiogenesis, a marker of cancer development, affects response to radiotherapy sensibility. This preclinical study aims to understand the receptor tyrosine kinase-mediated angiogenesis in head neck squamous cell carcinoma (HNSCC). The receptor tyrosine kinase activity in a transgenic mouse model of HNSCC was assessed. The anti-tumorigenetic and anti-angiogenetic effects of cetuximab-induced epidermal growth factor receptor (EGFR) inhibition were investigated in xenograft and transgenic mouse models of HNSCC. The signaling transduction of Notch1 and hypoxia-inducible factor-1α (HIF-1α) was also analyzed. EGFR was overexpressed and activated in the Tgfbr1/Pten deletion (2cKO) mouse model of HNSCC. Cetuximab significantly delayed tumor onset by reducing tumor angiogenesis. This drug exerted similar effects on heterotopic xenograft tumors. In the human HNSCC tissue array, increased EGFR expression correlated with increased HIF-1α and micro vessel density. Cetuximab inhibited tumor-induced angiogenesis in vitro and in vivo by significantly downregulating HIF-1α and Notch1. EGFR is involved in the tumor angiogenesis of HNSCC via the HIF-1α and Notch1 pathways. Therefore, targeting EGFR by suppressing hypoxia- and Notch-induced angiogenesis may benefit HNSCC therapy. [ABSTRACT FROM AUTHOR]

Based on (6, 0) zigzag carbon nanotubes (ZCNTs), a Stone–Wales defect ring ([5.7]3) is constructed at one end of the ZCNTs, forming a novel nanostructure [5.7]3ZCNT. The introduction of [5.7]3 breaks the centrosymmetry of the nanotube and remarkably changes electronic and magnetic properties of the nanotube. Unlike the (6, 0)ZCNT which has an open-shell singlet ground state, the [5.7]3ZCNT has a closed-shell singlet ground state with a large dipole moment, polarizability, and first hyperpolarizability. Interestingly, the [5.7]3ZCNT itself has a donor–π–acceptor framework, in which the Stone–Wales defect ring serves as an electron donor (D) while the zigzag nanotube works as an electron acceptor (A) and a conjugated bridge (π). Moreover, increasing both the tube diameter and tube length could enhance second-order nonlinear optical (NLO) responses, with the former being more effective than the latter. [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Quantum Chemistry is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For unusual e@CF ( I, D, and D) cage structures with two excess electrons, it is reported that not only the lone pair in singlet state but also two single excess electrons in triplet state can be encapsulated inside the CF cages to form single molecular solvated dielectrons. The interesting relationship between the shape of the cage and the spin state of the system has revealed that ground states are singlet state for spherical shaped e@CF ( I) and triplet states for short capsular shaped e@CF ( D) and long capsular shaped e@CF ( D), which shows a spin evolution from the singlet to triplet state with the deformation of the cage from spherical to capsular shape. For these excess electron systems, the three ground state structures have large vertical electron detachment energies (VDEs (I) of 1.720-2.283 eV and VDEs (II) of 3.959-5.288 eV), which shows their stabilities and suggests that the large CF cage is the efficient container of excess electrons. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011 [ABSTRACT FROM AUTHOR]

Copyright of International Journal of Quantum Chemistry is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

At various levels of theory, singlet and triplet potential energy surfaces (PESs) of Si2CO, which has been studied using matrix isolation infrared spectroscopy, are investigated in detail. A total of 30 isomers and 38 interconversion transition states are obtained at the B3LYP/6-311G(d) level. At the higher CCSD(T)/6-311+G(2d)//QCISD/6-311G(2d)+ZPVE level, the global minimum 11 (0.0 kcal/mol) corresponds to a three-membered ring singlet O-cCSiSi (1A′). On the singlet PES, the species 12 (0.2 kcal/mol) is a bent SiCSiO structure with a 1A′ electronic state, followed by a three-membered ring isomer Si-cCSiO (1A′) 13 (23.1 kcal/mol) and a linear SiCOSi 14 (1Σ+) (38.6 kcal/mol). The isomers 11, 12, 13, and 14 possess not only high thermodynamic stabilities, but also high kinetic stabilities. On the triplet PES, two isomers 31 (3B2) (18.8 kcal/mol) and 37 (3A″) (23.3 kcal/mol) also have high thermodynamic and kinetic stabilities. The bonding natures of the relevant species are analyzed. The similarities and differences between C3O, C3S, SiC2O, and SiC2S are discussed. The present results are also expected to be useful for understanding the initial growing step of the CO-doped Si vaporization processes. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009 [ABSTRACT FROM AUTHOR]

The elongation finite-field method is applied to calculate (hyper)polarizabilities of polyimides PMDA/DMDB, PMDA/ODA, and PMDA/TFDB. The nonlinear optical (NLO) properties of planar structures of three polyimides are compared to those of their twist structures. It is found that all α and γ values of the planar structures are larger than the corresponding values of the twist structures, which may be attributed to the fact that π-conjugation of twist structures is decreased compared with the planar structures. All β values of planar and twist structures oscillate regularly along with elongating the chain. Moreover, effect of two side-groups -CH3 and -CF3 on the NLO properties of PMDA/DMDB and PMDA/TFDB is investigated. [ABSTRACT FROM AUTHOR]

The structures, spectroscopies, and stabilities of the doublet Si2NO radical are explored at the density functional theory (DFT) and ab initio levels. Seventeen isomers are located, connected by 26 interconversion transition states. At the CCSD(T)/6-311+G(2df)//QCISD/6-311G(d)+ZPVE level, three low-lying isomers are predicted, that is, one bent species SiNSiO 3 (5.1 kcal/mol) containing the important Si&tbond;N triple bonding and two four-membered ring isomers including cyclic cSiNSiO 1 (0.0) with Si&bond;Si cross-bonding with C2v symmetry and puckered cSiNSiO 1′ (11.9) with divalent carbene character. Three low-lying isomers 1, 1′, and 3 have reasonable kinetic stabilities and might be observable either experimentally or astrophysically. The possible formation strategies of 1, 1′, and 3 in laboratory and in space are discussed in detail. The calculated vibrational frequencies and possible formation processes of 3 are consistent with recent experimental observations. In light of the fact that no cyclic nitrogen-containing species have been detected in space, two cyclic isomers 1 and 1′ could be promising candidates. Furthermore, the bonding nature of three isomers 1, 1′, and 3 is analyzed. The calculated results are also compared with those of the analogue C2NO radical. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007 [ABSTRACT FROM AUTHOR]

Abstract: The structures, energetics, spectroscopies, and stabilities of the doublet PC2S radical are explored at density functional theory and ab initio levels. Seven minimum isomers are located connected by 20 interconversion transition states. At the CCSD(T)/6-311+G(2df)//QCISD/6-311G(d)+ZPVE level, the lowest-lying isomer is a linear form PCCS 1 whose structure mainly resonates between and with the former bearing somewhat more weight. The species 1 is predicted to possess great kinetic stability about 50kcal/mol. Additionally, two high-lying isomers, i.e. bent CCPS 2 (52.0) and bent CCPS 2′ (54.9), are also stabilized by the considerable barriers of 21.0 and 18.1kcal/mol, respectively. Interestingly, the isomers 2 and 2′ can be easily converted to each other, both of them could coexist. All the three isomers should be experimentally or astrophysically observable. The bonding natures of the isomers 1, 2, and 2′ are analyzed. Their molecular properties including adiabatic ionization potentials and adiabatic electronic affinities are determined at the higher levels G3//B3LYP and G3(MP2)//B3LYP. The calculated results are compared with those of the analogues NC2S and NC2O. Possible formation strategies of the isomers 1, 2, and 2′ in laboratory and in space are also discussed. The present PC2S work represents the first detailed potential energy survey of the PC n S (n>1) series and can provide useful information for future laboratory and interstellar identification of various PC2S isomers. [Copyright &y& Elsevier]

Cell membrane coating nanotechnology, which endows nanoparticles with unique properties, displays excellent translational potential in cancer diagnosis and therapy. However, the preparation and evaluation of these cell membrane‐coated nanoparticles are based on cell lines and cell‐line‐based xenograft mouse models. The feasibility of cell membrane‐camouflaged nanomaterials is tested in a preclinical setting. Head and neck squamous cell carcinoma (HNSCC) patient‐derived tumor cell (PDTC) membranes are coated onto gelatin nanoparticles (GNPs) and the resulting PDTC@GNPs show efficient targeting to homotypic tumor cells and tissues in patient‐derived xenograft (PDX) models. When the donor‐derived cell membrane of PDTC@GNPs matched those of the host cells, significant targeting capability is observed. In contrast, mismatch between the donor and host results in weak targeting. Furthermore, it is demonstrated that autologous separation and administration of cellular membranes and anticancer cisplatin (Pt)‐loaded PDTC@GNPs, respectively, lead to almost complete tumor ablation in a subcutaneous model and effectively inhibit tumor recurrence in a postsurgery model. The work presented here reinforces the translation of these biomimetic nanoparticles for clinical applications and offers a simple, safe, and effective strategy for personalized cancer treatment. [ABSTRACT FROM AUTHOR]

Cell membrane–based nanosystems with desirable characteristics have been studied extensively for many therapeutic applications. However, current research has focused on single cell membrane, and multifunctional fused membrane materials from different membrane types are still rare. Herein, a platelet–cancer stem cell (CSC) hybrid membrane‐coated iron oxide magnetic nanoparticle (MN) {[CSC‐P]MN} is presented for the first time for the enhanced photothermal therapy of head and neck squamous cell carcinoma (HNSCC). Inherited from the original source cells, the platelet membrane shows immune evading ability due to the surface marker comprising a number of "don't eat me" signals, and the CSC membrane has homotypic targeting capabilities due to the specific surface adhesion molecules. The [CSC‐P]MNs possess superior characteristics for immune evasion, active cancer targeting, magnetic resonance imaging, and photothermal therapy. Compared with single cell membrane–coated MNs, [CSC‐P]MNs exhibit prolonged circulation times and enhanced targeting abilities. Moreover, the [CSC‐P]MNs exhibit a superior photothermal ability that provides excellent HNSCC tumor growth inhibition, particularly in an immunocompetent Tgfbr1/Pten conditional double knockout HNSCC mouse model that contains a more complex tumor microenvironment that is similar to the human HNSCC microenvironment. Collectively, this biomimetic multimembrane‐coated nanoplatform may provide enhanced antitumor efficacy in the complex tumor microenvironment. A natural cancer stem cell‐platelet hybrid mimic membrane is collected from tumor‐bearing mice and further used for magnetic nanoparticle coating. The obtained biomimetic nanoparticles are then injected into the same mice for magnetic resonance imaging and photothermal therapy. The work presents a novel design strategy for personalized cancer theranostics. [ABSTRACT FROM AUTHOR]

Objective Materials and Methods Results Conclusions Ferroptosis has been defined as a novel form of regulated cell death characterized by iron‐dependent lipid peroxidation. Manganese has been used to induce ferroptosis in cancer cells recently. This study aims to investigate whether manganese can induce ferroptosis in oral squamous cell carcinoma (OSCC) and the underlying biological mechanisms.Cancer cells with or without manganese treatment were analyzed by RNA‐sequencing to identify ferroptosis‐related genes. Next, the activation of YAP/TAZ/ACSL4‐ferroptosis signaling pathway was detected. Bioinformatic analysis and immunofluorescence assay were used to explore the phase separation of YAP/TAZ. Finally, specimens of OSCC patients were applied to analyze the clinical significance of YAP/TAZ/ACSL4.RNA‐sequencing analysis showed the ferroptosis‐related genes and YAP/TAZ were upregulated after manganese treatment. The results of immunofluorescence, ELISA, western blotting, etc. further confirmed that manganese‐induced ferroptosis depends on YAP/TAZ/ACSL4 signaling pathway. Moreover, the activation of ACSL4 was achieved by YAP/TAZ phase separation. The survival analysis in OSCC specimen suggested that the higher level of YAP/TAZ‐ACSL4 axis expression indicates longer survival.Manganese induces YAP/TAZ phase separation and subsequent ACSL4 activation via YAP/TAZ nuclear translocation, which facilitates ferroptosis of OSCC. Then YAP/TAZ‐ACSL4 axis can be used as a potential prognostic predictor of OSCC patients. [ABSTRACT FROM AUTHOR]