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Rock-boring behavior is a common phenomenon among certain bivalve clams, yet the mechanisms enabling this capability remain elusive. This study delves into the microstructural and micromechanical properties of the shells and denticles of angelwing (Cyrtopleura costata), a rock-boring clam. X-ray Diffraction Analysis and Energy-dispersive Spectroscopy identify that angelwing shells are made of pure aragonite. Scanning Electron Microscope images reveal that angelwing shells are mostly made of submicrometer-thick lamellar sheets, which are packed closely forming crossed-lamellar groups. Nanoindentation tests yield Young's Moduli of 30-70GPa and hardness of 3-10GPa at different parts of the shells, making angelwing clam shells among the hardest biological materials. Further numerical simulations validate that the crossed-lamellar microstructure excels in withstanding external loads and safeguarding the integrity of the shell through minimized stress concentration. STATEMENT OF SIGNIFICANCE: Boring and drilling in rocks are important for construction, energy, and scientific exploration. Nature offers ideas for improving these techniques, as seen in the rock-boring angelwing clam. Our study focuses on the mechanical and micro-structural properties of the clam's shell, which help it bore into rocks. Through nanoindentation, we found that the clam's shell is one of the hardest and stiffest biological shells, a key factor in its boring ability. We also identified intricate shell structures that likely enhance its strength and resistance to mechanical stress. These findings highlight important bio-material traits that could inspire new, more efficient drilling technologies for human use., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Published by Elsevier Ltd.)

Diabetic wound treatment continues to be a significant clinical issue due to higher levels of oxidative stress, susceptibility to bacterial infections, and chronic inflammatory responses during healing. We rationally developed and synthesized an ultra-small carbon dots (C-dots) loaded with zinc single-atom nanozyme (Zn/C-dots) with the aim of promoting wounds healing by nanocatalytic treatment, especially targeting its complex pathological microenvironment. Zinc single atoms and C-dots form a dual catalytic system with higher enzymatic activity. Furthermore, the Zn/C-dots nanozyme effectively enters cells, accumulates at mitochondria, and removes excess ROS, protecting cells from oxidative stress damage and limiting the release of pro-inflammatory cytokines, hence reducing inflammation. Zinc can synergistically increase the antibacterial action of C-dots (the effective antibacterial rate of 100 µg/mL Zn/C-dots was above 90 %). Unlike traditional C-dots, Zn/C-dots can cause endothelial cell migration and the formation of new blood vessels. In vitro cytotoxicity, blood compatibility, and in vivo toxicity studies of Zn/C-dots show that they are biocompatible. We subsequently utilized the Zn/C-dots nanozymes to treat diabetic rats' chronic wounds for external use, combining them with ROS-responsive hydrogels to create an antioxidative system (H-Zn/C-dots). The hydrogels anchored the Zn/C-dots nanozymes to the wound, allowing for long-term treatment. The results revealed that H-Zn/C-dots can considerably reduce inflammation, accelerate angiogenesis, collagen deposition, and promote tissue remodeling at the diabetic wound site. After 14 days, the wound area had decreased to approximately 9.19 %, making it a potential treatment. STATEMENT OF SIGNIFICANCE: An ultra-small carbon dot with a zinc single-atom nanozyme was designed and manufactured. Zn/C-dots possess antibacterial, ROS-scavenging, and angiogenesis activities. In vivo, the multifunctional ROS-responsive hydrogel incorporating Zn/C-dots could speed up diabetic wound healing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

Colorectal cancer (CRC) is one of the deadliest malignancies worldwide, ranking third in incidence and second in mortality. Remarkably, early stage localized CRC has a 5-year survival rate of over 90%; in stark contrast, the corresponding 5-year survival rate for metastatic CRC (mCRC) is only 14%. Compounding this problem is the staggering lack of effective therapeutic strategies. Beyond genetic mutations, which have been identified as critical instigators of CRC initiation and progression, the importance of epigenetic modifications, particularly DNA methylation (DNAm), cannot be underestimated, given that DNAm can be used for diagnosis, treatment monitoring and prognostic evaluation. This review addresses the intricate mechanisms governing aberrant DNAm in CRC and its profound impact on critical oncogenic pathways. In addition, a comprehensive review of the various techniques used to detect DNAm alterations in CRC is provided, along with an exploration of the clinical utility of cancer-specific DNAm alterations., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Dopamine is a small molecule inspired by the dopamine motif of mussel foot proteins, and PDA is formed by the self-polymerization of dopamine. Under the UV-irradiation，PDA would be oxidized by reactive oxygen species (ROS) which were produced by photocatalytic reactions on TiO 2 surfaces，thus regulating the adhesion behavior of endothelial cells (ECs) TiO 2 inhibited platelet (Plt) adhesion after UV exposure. Polydopamine (PDA)-TiO 2 micropatterns (P-PDA-TiO 2 ) were prepared by magnetron sputtering and photolithography. This micropatterns successfully achieves selective adhesion of Plt and ECs. The selective adhesion of ECs disappears after vacuum reduction. In contrast to conventional cell patterning strategies, P-PDA-TiO 2 can easily achieve pattern separation of ECs and Plts and provide a new concept for building complex blood-contacting devices., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In-stent restenosis (ISR) and late thrombosis, usually caused by excessive smooth muscle cell (SMC) proliferation and delayed endothelial layer repair, respectively, are the main risks for the failure of vascular stent implantation. For years, modification of stents with biomolecules that could selectively inhibit SMC proliferation and support endothelial cell (EC) growth had drawn extensive attention. However, the modulatory effect of these biomolecules faces the impact of oxidative stress, inflammation, and hyperlipidemia of the pathological vascular microenvironment, which is caused by the stent implantation injury and atherosclerosis lesions. Here, we modified stents with a natural and multi-functional flavonoid, baicalin (BCL), using poly-dopamine (PDA) coating technology to combat the harmful impact of the pathological microenvironment. Stent with an appropriate BCL immobilization density (approximately 2.03 μg/cm2) successfully supported ECs growth while inhibited SMC proliferation. Furthermore, baicalin-modified surfaces regulated the oxidative stress, inflammation, and high-lipid of the pathological microenvironment to inhibit endothelial dysfunction and the oxidized low-density lipoprotein (ox-LDL)-induced macrophage foam cells formation. In vivo results showed that baicalin-modified stents exhibited significant anti-ISR, anti-inflammatory, and endothelialization-promoting functions. Our study suggests that the multi-functional baicalin with pathological microenvironment-regulation (PMR) effect has potential use in the surface engineering of cardiovascular devices. STATEMENT OF SIGNIFICANCE: Empowering vascular stents with selective modulation of smooth muscle cells and endothelial cells by surface technology has become an important research direction for stent surface engineering. However, stent coatings that can furthermodulate the pathological microenvironment of blood vessels have been rarely reported. In this study, we constructed a multifunctional coating based on a flavonoid, baicalin, which can selectively modulate vascular wall cells and improve the pathological microenvironment. This study may provide a reference for developing advanced vascular stents., Competing Interests: Declaration of Competing Interest We declare that we have no financial and personal relationships with other people or organizations that can inappropriately influence our work. there is no professional or other personal interest of any nature or kind in any product, service and/or company that could be construed as influencing the position presented in, or the review of, the manuscript entitled., (Copyright © 2022. Published by Elsevier Ltd.)

It is generally believed that the enhancement of phytoplankton appears only in shallow and intermediate depth seamounts, while the phenomenon has also been observed in some deep seamounts by satellites recently. To figure out what effect do deep seamounts have on phytoplankton and the relevant mechanisms, the phytoplankton biomass and community on the Kocebu Seamount (depth: 1198 m) were studied. The results showed that the average Chl a concentration of the seamount was 0.09 mg·m -3 , and the Chl a maximum layer was mainly located at 150 m, and picophytoplankton such as prochlorophytes and cyanobacteria were the dominant groups. High Chl a patches (>0.2 mg·m -3 ) were mainly distributed within 20 km of the peak, and both nitrate and orthophosphate were obviously uplifted at the peak. The physical data indicated the uplifted of nutrients could be caused by the internal tides, which generated by the interaction of topography and tide. This is the first time that the promotion of phytoplankton was observed in situ on a deep seamount, and this study expounded relevant mechanisms and suggested that the ecological functions of deep seamounts may have been previously neglected., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Five alkaloids, including two previously undescribed alkaloids, named forsyshiyanines A and B, attributable to the rare skeletons 4b,5,6,7,8,8a,9,10-octahydrobenzo[f]quinoline and (6,7-dihydro-5H-cyclopenta[c]pyridin-7-yl)methyl, respectively, along with three known ones (3-5), were isolated from the ripe fruits of Forsythia suspensa. The chemical structures including absolute configurations of two undescribed compounds were established using integrated spectroscopic techniques, electronic circular dichroism calculations, and single-crystal x-ray diffraction analysis. In vitro, five alkaloids showed anti-inflammatory activities, with the inhibition rates of the release of β-glucuronidase from polymorphonuclear leukocytes of rats being in the range 47.9%-56.0% at a concentration of 10 μM. Moreover, five compounds exhibited anti-viral activities against influenza A virus and respiratory syncytial virus, with IC 50 values in the range of 7.3-32.5 μM and EC 50 values in the range 3.7-14.1 μM., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Titanium dioxide (TiO 2 ) is a widely used biomaterial. It is a great challenge to confer antibacterial and antithrombotic properties to TiO 2 while maintaining its cell affinity. Here, we developed a new strategy to achieve the above goal by comprehensively controlling the chemical cues and geometrical cues of the surface of TiO 2 . Using colloidal etching technology and UV irradiation treatment, we obtained the photofunctionalized nano-micro-honeycomb structured TiO 2 . The honeycomb structured increased the photocatalytic activity of TiO 2 , which endowed TiO 2 with photo-induced superhydrophilicity to inhibit bacterial adhesion. The high photocatalytic activity also induced the strong photocatalytic oxidation of TiO 2 surface organic adsorbates to suppress fibrinogen and platelet attachment. In addition, owing to the micropore trapping-isolation effect on the bacteria and the nano-frames' contact guidance effect on the growth and spreading of platelet pseudopods, the honeycomb structure also shows a considerable inhibiting effect on bacterial and platelet adhesion. Therefore, due to the controlled chemical and geometrical cues' synergistic effect, the photo-functionalized TiO 2 honeycomb structure shows excellent bacterial-adhesion resistance and antithrombotic properties. More importantly, the photo-functionalized TiO 2 honeycomb did not inhibit the adhesion and growth of endothelial cells (ECs) after culturing for 3 d, indicating a good cell affinity that the traditional antifouling surfaces do not possess., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Objective: Securidaca inappendiculata is a medicinal plant frequently used in the treatment of inflammatory diseases in south China. In this study, we aimed to explore its bioactive constituent which contributes to the anti-inflammatory activity., Methods: Polyphenol-enriched and polyphenol-deprived fractions (PRF and PDF, respectively) were separated from the ethanolic extract by HPD300 macroporous resin-based method, and their anti-inflammatory activities were investigated on a lipopolysaccharide (LPS)-induced acute lung injury (ALI) model in rats. The possible mechanism of action in alleviating acute inflammation was studied using RAW264.7 cells., Results: Both Folin-Ciocalteu and 1 H nuclear magnetic resonance (NMR) analyses showed that polyphenolic content in PRF was approximately 10 times higher than that of PDF, and this observation reflected in their antioxidative capacities. PRF but not PDF significantly decreased the level of malondialdehyde, suppressed the expression of nicotinamide phosphoribosyltransferase (NAMPT) protein, and improved the severity of ALI in rats. PRF at 10 μg/mL effectively downregulated the expression of proteins NAMPT, HMGB1, TLR4, and p-p65, and scavenged the intracellular reactive oxygen species (ROS) in LPS-primed RAW264.7 cells. N -acetyl- L -cysteine exhibited similar inhibitory effects on ROS production and NAMPT-mediated TLR4/NF-κB activation in vitro , whereas nicotinamide mononucleotide antagonized all the changes induced by PRF during cotreatments., Conclusion: As an antioxidant, PRF exhibited potent anti-inflammatory activity under both in vivo and in vitro conditions by downregulating NAMPT and TLR4/NF-κB. Accordingly, polyphenols were identified as important bioactive constituents in S. inappendiculata targeting oxidative stress-sensitive pro-inflammatory pathways., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2021 Tianjin Press of Chinese Herbal Medicines. Published by ELSEVIER B.V.)

The tropical western Pacific, one of the most oligotrophic seas on Earth, has a large number of seamounts. In this sea, we hypothesize that although the presence of shallow seamounts can enhance phytoplankton biomass, they do not alter the phytoplankton community composition. The concentration and distribution of size-fractionated chlorophyll a (Chl a) on the C4 Seamount were measured, and the phytoplankton community was analyzed based on photosynthetic pigments. The results showed that the deep chlorophyll maximum (DCM) was located between 100 and 150 m and that picophytoplankton such as prochlorophytes and cyanobacteria (mainly Synechococcus) were the dominant groups, contributing approximately 85% of the Chl a. The integrated Chl a concentration above the seamount was significantly higher than that off the seamount, and most communities were enhanced near the peak. The physical, chemical, and biological coupling processes of the C4 Seamount support the classic hypothesis of the seamount effect. However, the relative contributions of different phytoplankton groups to Chl a were not significantly different between stations above and off the seamount, and the analysis of similarities among results also indicated that the community composition on the C4 Seamount did not differ significantly from that off the seamount. In addition, size-fractionated Chl a data from two nearby shallow seamounts also supported our hypothesis. More studies on the ecology of seamounts in the tropical western Pacific are required to further confirm and refine these results., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Five previously undescribed labdane diterpenoids, named Forsypensins A-E, were isolated from the fruits of Forsythia suspensa. The structures and relative configurations of the compounds were elucidated via extensive spectroscopic methods, and their absolute configurations were fully confirmed by single crystal X-ray diffraction analyses using Cu Kα radiation and electronic circular dichroism data. The five labdane diterpenoids showed in vitro anti-inflammatory activity in rat polymorphonuclear leukocytes, inhibiting the rates of β-glucuronidase release by 43.6%-49.2% at concentrations of 10 μM. The compounds also had anti-viral activity against influenza A (H1N1) virus and respiratory syncytial virus (RSV), with IC 50 values in the range 21.8-27.4 μM, and EC 50 values in the range 10.5-15.4 μM, respectively., Competing Interests: Declaration of competing interest The authors confirm that the contents of this article involve no conflicts of interest., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Eight labdane diterpenoids, including two new labdane diterpenoids, named forsyshiyanins A-B (2-3), along with six known ones (1, 4-8), were isolated from the fruits of Forsythia suspensa. The new structures including their absolute configurations were elucidated by extensive spectroscopic analyses, X-ray diffraction and computational calculation. In vitro, eight labdane diterpenoids showed anti-inflammatory activities, with the inhibition rates of release of β-glucuronidase from polymorphonuclear leukocytes of rats being in the range 46.8-51.0% at concentrations of 10 µM, as well as anti-viral activities against influenza A (H1N1) virus and respiratory syncytial virus (RSV), with the IC 50 values in the range 18.4-26.2 μM and EC 50 values in the range 10.5-14.4 μM, respectively., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest., (Copyright © 2020. Published by Elsevier Inc.)

A double tilting holder with high stability is essential for acquiring atomic-scale information by transmission electron microscopy (TEM), but the availability of such holders for in situ TEM studies under various external stimuli is limited. Here, we report a unique design of seal-bearing components that provides ultra-high stability and multifunctionality (including double tilting) in an in situ TEM holder. The seal-bearing subsystem provides superior vibration damping and electrical insulation while maintaining excellent vacuum sealing and small form factor. A wide variety of in situ TEM applications including electrical measurement, STM mapping, photovoltaic studies, and CL spectroscopy can be performed on this platform with high spatial resolution imaging and electrical sensitivity at the pA scale., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Four undescribed flavonoid alkaloids, as two pairs of enantiomers, were initially isolated as a racemate from the whole plant of Scutellaria moniliorrhiza. By means of chiral HPLC, four isomers, named scumonilines A-D, were successfully separated, and their chemical structures including absolute configurations were established by mass as well as NMR spectroscopy and CD technique. In vitro, four flavonoid alkaloids showed anti-inflammatory activities, with IC 50 values against the release of β-glucuronidase from polymorphonuclear leukocytes of rats being in the range 5.16-5.85 μΜ. Moreover, four compounds were evaluated for their inhibitory activities against aldose reductase, and gave IC 50 values in the range 2.29-3.03 μΜ., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Poly (N-isopropylacrylamide) (PNIPAAm) is a thermosensitive polymer with various biomedical applications. We examined molecular weight (MW)-dependent cytotoxicity of PNIPAAm. Our results indicated that low-MW PNIPAAm (degree of polymerization (DP)=35) is inherently toxic to cells. Moderate-MW PNIPAAms with their DP between 100 and 200 are non-cytotoxic. When cells are seeded on top of a polymer-coated surface, PNIPAAm with a higher MW (DP=400) shows non/low cytotoxicity, while when monolayer cells are exposed to the polymer solution, cell viability drops drastically. This may be due to lack of nutrient and oxygen rather than intrinsic toxicity of the polymer., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Objectives: Recent studies have suggested immunomodulatory and anti-inflammatory effects of cannabinoid receptor 2 (CB2R) activation, which is devoid of psychoactivity. We have demonstrated the expression of CB2R in synovial tissue from patients with rheumatoid arthritis (RA), and its specific activation shows inhibitory effects on fibroblast-like synoviocytes. However, it is still unclear whether selective activation of CB2R inhibits joint inflammation or protects joint damage in RA., Methods: A murine model of collagen-induced arthritis (CIA) was used to evaluate the therapeutic efficacy of HU-308, a selective CB2R agonist. The disease severity was evaluated by semi-quantitative scoring of joint swelling, histological assessment of joint inflammation and structure, and radiographic assessment of joint destruction by using digital plain radiographs and micro-CT scans. The concentrations of various isotypes of anti-collagen II antibodies in sera and the levels of cytokines in culture supernatants were determined by ELISA., Results: Compared with vehicle treatment, protective treatment with intraperitoneal injection of HU-308 (0.3-1.0 mg/kg) failed to decrease the incidence of the development of CIA, but it effectively suppressed the severity of the disease. In CIA mice, treatment with HU-308 significantly decreased joint swelling, synovial inflammation, and joint destruction, as well as serum levels of anti-collagen II antibodies. In vitro, HU-308 (1-10 μM) significantly suppressed the production of proinflammatory cytokines IL-6 and TNF-α from lipopolysaccharide-stimulated murine peritoneal macrophages with intact CB2R in dose-dependent manners. HU-308 failed to elicit any inhibitory effect of on lipopolysaccharide-stimulated macrophages from CB2R-knockout mice., Conclusions: Activation of CB2R by HU-308 has therapeutic potential for RA to suppress synovitis and alleviate joint destruction by inhibiting the production of autoantibodies and proinflammatory cytokines., (Copyright © 2014 Elsevier GmbH. All rights reserved.)

Immobilization of the enzymes on nano-structured materials is a promising approach to enhance enzyme stabilization, activation and reusability. This study aimed to develop polystyrene fiber-enzyme assembles to catalyze model formaldehyde to methanol dehydrogenation reaction, which is an essential step for bioconversion of CO2 to a renewable bioenergy. We fabricated and modified electrospun polystyrene fibers, which showed high capability to immobilize dehydrogenase for the fiber-enzyme assembles. Results from evaluation of biochemical activities of the fiber-enzyme assemble showed that nitriation with the nitric/sulfuric acid ratio (v/v, 10:1) and silanization treatment delivered desirable enzyme activity and long-term storage stability, showing great promising toward future large-scale applications., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Treatment of human diseases at gene level is always limited by effective gene delivery vectors. In this study, we designed and developed an endosomal pH sensitive targeted gene delivery system, folic acid functionalized Schiff-base linked imidazole chitosan (FA-SLICS), for cancer therapy. The FA-SLICS is able to self-assemble plasmid DNA (pDNA) into nano-scaled polyplexes under a neutral condition and to release the loaded pDNA in the endosomal microenvironment due to the presence of pH sensitive Schiff-base moieties along chitosan backbones. The FA-SLICS has negligible cytotoxicity to normal cells (CHO), but displays slight toxicity to cancer cells (HeLa and HepG2). In addition, FA-SLICS can selectively and efficiently transfect FR (folate receptor) positive cells (HeLa cells) as a gene carrier. Therefore, the FA-SLICS should be a promising delivery vector in cancer gene therapy based on its cell targeting capability and intracellular microenvironment controlled delivery mechanism., (Copyright © 2014 Elsevier B.V. All rights reserved.)

One new eudesmane-type (1, named solajiangxin A) and two new eudesmane-related sesquiterpenoids (2-3, named solajiangxins B-C) were isolated from the whole plant of Solanum lyratum. Their structures were elucidated on the basis of integrated spectroscopic techniques. In vitro, three new sesquiterpenoids were found to show significant cytotoxicities against three human cancer lines (P-388, HONE-1 and HT-29), and gave ED50 values in the range of 1.9-3.7 μg/ml., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Three functionalized ionic liquids (ILs), tetrabutylammonium di(2-ethylhexyl)phosphate ([TBA][DEHP]), trioctylmethylammonium di(2-ethylhexyl)phosphate ([TOMA][DEHP]), and trihexyl(tetradecyl)phosphonium di(2-ethylhexyl)phosphate ([THTP][DEHP]), are synthesized and characterized. These ILs are used as DEHP-based ionic extractants and are investigated for rare earth elements (REEs) separation in 1-hexyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([C(6)mim][NTf(2)]) and diisopropylbenzene (DIPB) along with di(2-ethylhexyl)phosphoric acid (HDEHP). Solubilities of the DEHP-based ionic extractants in [C(6)mim][NTf(2)] are much better than that of HDEHP in [C(6)mim][NTf(2)]. We herein report the achievement of enhanced extractabilities and selectivities for separation of REEs using DEHP-based ionic extractants in [C(6)mim][NTf(2)]. This work highlights the potential of developing a comprehensive ionic liquid-based extraction strategy for REEs using ionic liquids as both extractant and diluent., (Copyright © 2011 Elsevier B.V. All rights reserved.)

In order to minimize the side effect of cancer chemotherapy, a novel galactosamine-mediated drug delivery carrier, galactosamine-conjugated albumin nanoparticles (GAL-AN), was developed for targeted liver cancer therapy. The albumin nanoparticles (AN) and doxorubicin-loaded AN (DOX-AN) were prepared by the desolvation of albumin in the presence of glutaraldehyde crosslinker. Morphological study indicated the spherical structure of these synthesized particles with an average diameter of around 200 nm. The functional ligand of galactosamine (GAL) was introduced onto the surfaces of AN and DOX-AN via carbodiimide chemistry to obtain GAL-AN and GAL-DOX-AN. Cellular uptake and kinetic studies showed that GAL-AN is able to be selectively incorporated into the HepG2 cells rather than AoSMC cells due to the existence of asialoglycoprotein receptors on HepG2 cell surface. The cytotoxicity, measured by MTT test, indicated that AN and GAL-AN are non-toxic and GAL-DOX-AN is more effective in HepG2 cell killing than that of DOX-AN. As such, our results implied that GAL-AN and GAL-DOX-AN have specific interaction with HepG2 cells via the recognition of GAL and asialoglycoprotein receptor, which renders GAL-AN a promising anticancer drug delivery carrier for liver cancer therapy., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Two new neo-clerodane diterpenoids have been isolated from the whole plant of Scutellaria barbata D. Don, and their structures were established by detailed spectral analyses as scutehenanine H (1) and 6-(2,3-epoxy-2-isopropyl-n-propoxyl)barbatin C (2). In vitro, the isolated two new compounds showed significant cytotoxic activities against three human cancer lines, and gave IC(50) values in the range OF 2.0-4.2 μΜ., (Copyright © 2010 Elsevier B.V. All rights reserved.)

(27)Al MAS and 3QMAS NMR have been used to study Al(2)O(3)/TiO(2) catalyst supports synthesized via excess-solution impregnation and surface sol-gel methods. Temperature and alumina loading level strongly affect chemical states of aluminum oxide species observed. Surface cations, Al(H2O)6(3+), a surface alumina monolayer, and disordered transitional aluminas (multilayers) and alpha-alumina, coexist on the TiO(2) surface. Chemical shift and quadrupole coupling constants are reported for the major species identified in 3QMAS experiments. Gold particle catalysts prepared from supports calcined at 500 degrees C have optimum catalytic activity in CO oxidation, and smallest gold particle size for supports, which show maximum monolayer type octahedral alumina on the titania surface., (Copyright 2010 Elsevier Inc. All rights reserved.)

N-maleoylchitosan (NMCS) is a biocompatible derivative of chitosan, but its solubility in water is dependent on the degree of maleoyl substitution. In this study, the NMCS sample with a maleoyl substitution degree of 70% was synthesized by the reaction of maleic anhydride and the amino groups of chitosan. The resulting NMCS can be ready to dissolve in water over a wide pH range (from 2 to 9). The aggregation behavior of NMCS in aqueous media was studied by steady-state fluorescence spectroscopy, viscometric, field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). The critical aggregation concentration (CAC) of NMCS in water is found to be 0.05-0.06mg/mL. With increasing NMCS concentration to approximately 0.5mg/mL, which is 10 times of the CAC, NMCS molecules self-assemble to fiber-like aggregates with an averaged diameter of approximately 2.5microm and length of more than 100microm. The driving force for the aggregation is attributed to the hydrophobic interaction as evident from isothermal titration calorimetry (ITC) study. These fiber-like aggregates might have potential applications in tissue engineering scaffold.

The preparation of sulfur-containing aryl and heteroaryl vinyl co-monomers via Suzuki-Miyaura cross-coupling between the corresponding mercaptomethyl arylboronates and in situ-generated vinyl bromides is described. Surface enhanced Raman scattering (SERS) studies of the target compounds on gold nanoparticles confirmed their potential as spectroscopic tags in the fabrication of SERS-encoded polymers for combinatorial screening and biomedical diagnostics.

Fe(3)O(4) nanoparticles were stabilized using different functional polysaccharides, such as chitosan (CS), O-carboxymethylchitosan (OCMCS) and (N-succinyl-O-carboxymethylchitosan (NSOCMCS) to improve their bioactivity. The release profile and the in vitro cancer cell inhibition activity of camptothecin (CPT) loaded polysaccharide modified Fe(3)O(4) nanoparticles were systematically studies. The particle size and size distribution of CPT-loaded polysaccharide modified Fe(3)O(4) nanoparticles were found to be strongly dependent on polysaccharide character. Such polysaccharide character could also affect CPT adsorption efficiency, CPT release behavior and bovine serum albumin (BSA) unspecific binding capacity. After 24 h incubation of 7721 cancer cells with CPT-loaded polysaccharide modified Fe(3)O(4) nanoparticles, significant changes in cell morphology could be discernible from phase contrast microscopy. Cytotoxicity assay showed these polysaccharide modified Fe(3)O(4) nanoparticles did not exhibit noteworthy cytotoxicity against 7721, however, the in vitro inhibition rate of CPT-loaded polysaccharide modified Fe(3)O(4) nanoparticles against 7721 liver cancer cell increased significantly in comparison with that of CPT-free drug.

Three neo-clerodane diterpenoids, named barbatins A-C (1-3), and the neo-clerodane diterpenoid nicotinyl ester, named scutebarbatine B (4), were isolated from the whole plant of Scutellaria barbata D. Don. Their structures were elucidated by spectroscopic analyses (UV, IR, HRFAB-MS, 1D NMR and 2D NMR). In vitro, compounds 1-4 showed significant cytotoxic activities against three human cancer lines, namely, HONE-1 nasopharyngeal, KB oral epidermoid carcinoma, and HT29 colorectal carcinoma cells, with IC50 values in the range 3.5-8.1 microM.

The effects of salt with different valences (NaCl, CaCl2 and CrCl3) on the aggregation of O-carboxylmethylchitosan (OCMCS) in dilute aqueous solution were investigated using viscometry, dynamic laser light scattering (DLS) and atomic force microscopy (AFM). With increasing OCMCS concentration beyond a critical aggregation concentration (cac) of approximately 0.045 g/l, the aggregation of OCMCS appears in solution. The driving forces of the OCMCS aggregation are intermolecular hydrogen bond, hydrophobic interaction and electrostatic repulsion. The OCMCS aggregation behavior strongly depends on the valence of salt. When NaCl is added, the aggregate size increases with NaCl concentration. When CaCl2 or CrCl3 is added to a given OCMCS concentration, there exists a critical concentration each of Ca2+ and Cr3+. Before the critical concentration, the aggregates decrease in size with increasing salt concentration due to the intra-aggregate complexation; while after the critical concentration, the size of the aggregates increases with salt concentration due to the inter-aggregate complexation. Moreover, the effect of Cr3+ on the OCMCS aggregation is greater than that of Ca2+. The formation of the intra-aggregate complexation is found to be a kinetic process and the aggregate size decreases with time; the formation of the inter-aggregate complexation is also kinetic where the aggregate size increases with time. The aggregates dominated by the intra-aggregate complexation are small, compact and spherical, while the aggregates dominated by the inter-aggregate complexation show the big, compact and spherical morphology.

O-Carboxymethylchitosan (OCMCS) is a kind of biocompatible derivatives of chitosan whose water solubility is strongly dependent on the degree of carboxymethylation. The OCMCS with 100 carboxymethyl groups and 75 amino groups per 100 anhydroglucosamine units of OCMCS was synthesized by the reaction of chitosan and monochloroacetic. When OCMCS was dissolved in water, its solution was neutral and OCMCS behaved like a weak polyanionic polyeclectrolyte because most of carboxylic groups were not dissociated in neutral aqueous solution. The aggregation behavior of OCMCS in aqueous solution was studied by surface tensiometry, steady-state fluorescence spectroscopy and viscometry. The critical aggregation concentration (cac) of OCMCS was determined to be between 0.042 mg/ml and 0.050 mg/ml. The possible aggregation mechanism of OCMCS in water was elucidated.

Five Diels-Alder type adducts, named guangsangons F, G, H, I, and J, along with two known compounds, mulberrofuran J and kuwanon J, were isolated from Morus macroura Miq. Their structures were determined by means of spectroscopic analyses and chemical methods. These compounds were regarded biogenetically as Diels-Alder type adducts of dehydroprenylphenols and chalcone derivatives, and (1)H NMR variable temperature experiments suggested that they all existed as an equilibrium mixture of conformational isomers in solution. Among the isolated new compounds, guangsangons H, I, and J displayed potent antioxidant activities and moderate anti-inflammatory activities.

Silica gels believed to be grafted with dithioacetal derivatives were recently used for Hg(II) extraction, and were found to selectively remove 94-100% of Hg(2+) ions from metal ion mixtures. The current studies with one derivative suggest that the functional group in the Hg(II) removal is the mercapto (SH) ligand. The dithioacetal group in (ClCOCH(2)S)(2)CHPh (2) was hydrolyzed during its reaction with amine (O)(3)Si(CH(2))(3)NH(2) (3) grafted on silica gel to give the mercapto ligand (O)(3)Si(CH(2))(3)NHCOCH(2)SH (4). The silica gel grafted with the mercapto ligand 4 selectively removed Hg(2+) ions with reported high capacities.