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Commercially valuable chenodeoxycholic acid (CDCA) was firstly developed from undesirable allo‐CDCA via multiple reactions: esterification, selective oxidation of C3‐hydroxy, the introduction of 1,4‐dien through IBX and TFA, the stereoselective hydrogenation by Pd/C under basic solution, deprotection, enzymatic reduction of C3‐carbonyl. During the process, highly selective oxidants were found to oxidize the C3‐hydroxy generating allo‐3‐keto bile acid which was used as substrates to investigate the dehydrogenation under IBX, and the possible hydrogenation mechanism under Pd/C had been proposed based on the crystal data. [ABSTRACT FROM AUTHOR]

Nine quinoline‐1,2,4‐triazine hybrids (5 a–5 i) were designed, synthesized, and subjected to evaluation as potential anti‐cancer agents. Structures validation of the synthesized analogues was accomplished through comprehensive analysis employing NMR, HRMS, and IR spectroscopy techniques. Furthermore, the molecular structures of compounds 5 a, 5 d and 5 h were authenticated via single crystal X‐ray diffraction. In an extensive screening process against the human pancreatic cancer PANC‐1 cell line utilizing the MTT assay, all quinoline‐1,2,4‐triazine hybrids (5 a–5 i) manifested significant anti‐proliferative activity. Compound 5 g demonstrated a significant anti‐proliferative effect with an IC50 value of 26.8 μM, similar to the positive control, 5‐Fu. Subsequent investigations revealed varying degrees of cell viability in MDA‐MB‐231, A549, and UM‐UC‐3 cell lines upon exposure to different concentrations of compound 5 g. These findings lead us to postulate that compound 5 g may impede the migration, invasion, and adhesion of PANC‐1 cells, similar to the effects observed with 5‐Fu. [ABSTRACT FROM AUTHOR]

Peroxisomal compartmentalization has emerged as a highly promising strategy for reconstituting intricate metabolic pathways. In recent years, significant progress has been made in the peroxisomes through harnessing precursor pools, circumventing metabolic crosstalk, and minimizing the cytotoxicity of exogenous pathways. However, it is important to note that in methylotrophic yeasts (e.g. Pichia pastoris), the abundance and protein composition of peroxisomes are highly variable, particularly when peroxisome proliferation is induced by specific carbon sources. The intricate subcellular localization of native proteins, the variability of peroxisomal metabolic pathways, and the lack of systematic characterization of peroxisome targeting signals have limited the applications of peroxisomal compartmentalization in P. pastoris. Accordingly, this study established a high‐throughput screening method based on β‐carotene biosynthetic pathway to evaluate the targeting efficiency of PTS1s (Peroxisome Targeting Signal Type 1) in P. pastoris. First, 25 putative endogenous PTS1s were characterized and 3 PTS1s with high targeting efficiency were identified. Then, directed evolution of PTS1s was performed by constructing two PTS1 mutant libraries, and a total of 51 PTS1s (29 classical and 22 noncanonical PTS1s) with presumably higher peroxisomal targeting efficiency were identified, part of which were further characterized via confocal microscope. Finally, the newly identified PTS1s were employed for peroxisomal compartmentalization of the geraniol biosynthetic pathway, resulting in more than 30% increase in the titer of monoterpene compared with when the pathway was localized to the cytosol. The present study expands the synthetic biology toolkit and lays a solid foundation for peroxisomal compartmentalization in P. pastoris. [ABSTRACT FROM AUTHOR]

Many kinds of medicinal ingredients occur in Cirsium lineare that have good clinical efficacy, conferring on this species its high medicinal development value. However, with a rapidly changing global climate, it is increasingly imperative to study the factors affecting the habitat distribution and survival of species. We predicted the current and future distribution areas of suitable habitats for C. lineare, analyzed the importance of environmental variables in influencing habitat shifts, and described the alterations to suitable habitats of C. lineare in different periods (modern, 2050s, and 2070s) and scenarios (RCP2.6, RCP4.5, and RCP8.5). The results show that, under the current climate, the total suitable area of C. lineare is about 2,220,900 km2, of which the highly suitable portion amounts to ca. 292,600 km2. The minimum temperature of the coldest month, annual precipitation, and mean daily temperature range are the chief environmental variables affecting the distribution of habitat for C. lineare. In the same period, with rising greenhouse gas emission concentrations, the total suitable area will increase. In general, under future climate change, the suitable habitat for C. lineare will gradually migrate to the west and north, and its total suitable area will also expand. The results of this experiment can be used for the conservation and management of the wild resources of C. lineare. We can choose suitable growth areas to protect the medicinal resources of C. lineare through in situ conservation and artificial breeding. [ABSTRACT FROM AUTHOR]

Tumor metastasis and relapse mainly results in therapy failure and becomes a big challenge in oncology. Immunogenic cell death (ICD) of tumors mediated immunotherapy (IT) is attracting widely for solving that problem although achieving sufficient ICD and strong immune response is challenging for nanoparticles‐based cancer IT. Herein, a multifunctional polypeptide coordinate nanocomposite that possesses near infrared photothermia (PT) and responsive releases of nitric oxide (NO) and iron ions is constructed, which synergistically kills cancer cells and highly prohibits metastatic 4T1 cells invasion and migration by PT‐boosted NO release and ferroptosis (FT). Remarkably, triple FT‐NO‐PT treatment amplifies the ICD effects and outperforms combo/monotherapy FT‐PT and FT in cancer cells and tumors, which further activates dendritic cells maturation, and primed CD4+T and CD8+T cells immune responses and memory effects, playing four birds with one stone (i.e., FT‐NO‐PT‐IT). The PCSFG‐based FT‐NO‐PT not only fully eradicates 4T1 primary tumors, but also induces strong ICD, immune priming, and memory effects to reject rechallenged 4T1 tumors and inhibit malignant tumor metastasis, demonstrating synergistic amplified ICD effects with strong cell immunities and memory effects by a unified FT‐NO‐PT‐IT. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Diabetic wound healing is threatening worldwide and challenging in wound dressings. Aiming to inhibit heavy inflammation and bacterial infection in diabetic wounds, herein, we facilely construct a kind of NO‐releasing poly(L‐glutamic acid) (PGA) based graphene oxide (GO) hybrid hydrogel of HDGS at a lower solid percentage, presenting large microporous size of about 20 μm, mild photothermal conversion property, and good biocompatibility. Besides improving hemostasis performance, the less amount of GO endowed the hydrogel with near infrared (NIR) responsivity to control fast and pulsatile NO release for killing bacteria and inhibiting heavy inflammation to proheal diabetic wound, in which a broad spectrum of antibacterial activities toward killing S. aureus, E. coli and MRSA was achieved via a combined effect of photothermia and NO release. In vivo effective hemostasis was attained in a rat liver bleeding model with short hemostatic time of ~20 s and lower blood loss of 1.5%—2.0%. Moreover, the treatment of HDGS plus 4 times of mild NIR irradiation (10 min, 808 nm, 1 W/cm2 per time) performed superior full diabetic wound healing within 11—14 d, in which the regenerated skins were characteristic of thick epidermis/dermis, dense blood vessels, some hair follicles‐embedding, and high level of collagens. [ABSTRACT FROM AUTHOR]

Yeast cell factories have been increasingly employed for producing plant‐derived natural products. Unfortunately, the stability of plant natural product biosynthetic pathway genes, particularly when driven by the same sets of promoters and terminators, remains one of the biggest concerns for synthetic biology. Here we profile genomic loci flanked by essential genes as stable integration sites in a genome‐wide manner, for stable maintenance of multigene biosynthetic pathways in yeast. We demonstrate the application of our yeast integration platform in the construction of sanguinarine (24 expression cassettes) and ajmalicine (29 expression cassettes) de novo biosynthetic pathways for the first time. Moreover, we establish stable yeast cell factories that can produce 119.2 mg L−1 heteroyohimbine alkaloids (containing 61.4 mg L−1 ajmalicine) in shake flasks, representing the highest titer of monoterpene indole alkaloids (MIAs) ever reported and promising the complete biosynthesis of other high‐value MIAs (such as vinblastine) for biotechnological applications. [ABSTRACT FROM AUTHOR]

Stimuli‐responsive prodrug‐based nanoplatform with synergistic antitumor activity is of central importance to the development of promising nanomedicines for cancer therapy. Here, we describe a polydopamine‐drug conjugate nanocomposite (ZP‐PDA‐DOX) with targeted cancer photothermal‐chemotherapy (PTT‐CT), which constructed by a gradual copolymerization of dopamine (DA) and pH‐sensitive dopamine‐derived prodrug (DA‐DOX) into the porous channels of zeolite imidazolate frameworks‐8 (ZIF‐8), followed by PEGylation with amino‐terminated folic acid‐polyethylene glycol (NH2‐PEG‐FA) to acquire the high biocompatibility, specificity, and excellent tumor‐targeting property. The incorporation of polydopamine strengthened the stability and dispersion of ZIF‐8, and also conferred photothermal conversion effect. In the tumor acidic microenvironment, the acid‐labile hydrazone linker of DA‐DOX and ZIF‐8 promptly degraded to release activated DOX. Moreover, the generated hyperthermia due to the high photothermal conversion efficiency of PDA component could accelerate drug release, and simultaneously thermally ablate tumor tissue to maximize the DOX‐induced CT, which could also assist PTT to eradicate tumor cells. This study provides a promising strategy for targeted cancer PTT‐CT with synergistic anti‐tumor effect. [ABSTRACT FROM AUTHOR]

It is widely accepted that the retailer's use of strategic inventory can mitigate double marginalization and improve supply chain coordination. However, the recent literature of channel coordination only considers the effects of the retailer's strategic inventory, leaving the manufacturer's incentive to hold strategic inventory mostly unexplored. In reality, there are situations where the manufacturer's inventory can be observed or inferred by the retailer and hence affects the vertical interaction. In our two‐period dynamic model, we show that the manufacturer in equilibrium may carry a positive amount of inventory, which yields a significant impact on the equilibrium decisions and the supply chain players' profits. Specifically, we find that the manufacturer's use of strategic inventory commits a lower propensity to resume production in the second period, thereby encouraging the retailer to carry more strategic inventory at a higher wholesale price in the first period. The manufacturer's use of strategic inventory always hurts the retailer's profit but may enhance channel profit, consumer surplus, and social welfare. Moreover, we show that the manufacturer can earn an even higher profit by directly committing to no replenishment in the second period, observed in industries with longer production lead time and higher production setup costs. [ABSTRACT FROM AUTHOR]

Stimuli‐responsive polypeptide nanoassemblies exhibit great potentials for cancer nanomedicines because of desirable biocompatibility and biodegradability, unique secondary conformations, varying functionalities, and especially the stimuli‐enhanced therapeutic efficacy and reduced side effect. This review introduces the design and fabrication of stimuli‐responsive polypeptide nanoassemblies that exhibit endogenous stimuli (e.g., pH, reduction, reactive oxygen species, adenosine triphosphate and enzyme, etc.) and exogenous light stimuli (e.g., UV and near‐infrared light), which are biologically related or applied in the clinic. We also discuss the applications and prospects of those stimuli‐responsive polypeptide nanoassemblies that might overcome the biological barriers of cancer nanomedicines for in vivo administration. Much more effort is needed to accelerate the second‐generation stimuli‐responsive polypeptide nanomedicines for clinical transition and applications. This article is categorized under:Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease [ABSTRACT FROM AUTHOR]

Background: Despite Tricholoma matsutake has been used as natural health products with multiple medicinal properties, detailed information about its polyphenolic composition as sources of anti‐photoaging agents remains to be determined. Objective: To investigate the impact of polyphenols extracted from Tricholoma matsutake (TME) on Ultraviolet B (UVB)‐induced skin photoaging. Materials and Methods: Various factors of oxidative stress and inflammation as well as histological and immunohistochemical analysis in the mouse dorsal skin were determined after UVB radiation. Results: Topical administration with TME suppressed the UVB‐induced skin thickness, wrinkles and erythema, and increased skin collagen content. Furthermore, TME decreased reactive oxygen species (ROS) level, upregulated glutathione peroxidase (GSH‐Px), superoxide dismutase (SOD), catalase (CAT), and glucose‐6‐phosphate dehydrogenase (G6PDH) activities and inhibited the expression of IL‐1, IL‐6, IL‐8, and TNF‐α in mice irradiated with UVB. TME could reduce UVB‐induced p38 mitogen‐activated protein kinase (p38 MAPK) phosphorylation and effectively inhibited the activity of the transcriptional factor nuclear factor‐kappa B (NF‐κB), thereby reducing the cyclooxygenase‐2 (COX‐2) expression, which is an important mediator of inflammatory cascade leading to the inflammatory response. Conclusion: Our data demonstrated that TME had various beneficial effects on UVB‐induced skin photoaging due to its antioxidant and anti‐inflammatory activities, and it might be exploited as a promising natural product in skin care, anti‐photoaging and the therapeutic intervention of skin disorders related to both oxidative stress and inflammation. [ABSTRACT FROM AUTHOR]

Lycium barbarum have received an increasing popularity due to its powerful biological activity and medicinal use. However, the effect of Lycium barbarum on skin remains largely uncharacterized. The general purpose of this paper was to characterize the phenolic compounds in Lycium barbarum extract (LBE) using LC‐HRMS/QTOF method and to investigate whether topical administration of LBE can repair skin barrier dysfunction in mice. Our data demonstrated that LBE could not only decrease ROS level and matrix metalloproteinase expression, but also strengthen intrinsic antioxidant defense system including SOD, GSH‐Px and CAT, thereby resulting in increased skin collagen content and an improvement of UV‐induced skin erythema, thickness and wrinkles. Improved skin barrier functions were highly correlated with increased expression of filaggrin, involucrin and loricrin as well as antioxidant proteins such as Nrf2 and HO‐1 in UV‐irradiated mice, suggesting that LBE may be promising natural products at a lower cost for the topical application in the treatment of skin diseases with defective barrier function. [ABSTRACT FROM AUTHOR]

Mitochondrion is generally considered as the most promising subcellular organelle for compartmentalization engineering. Much progress has been made in reconstituting whole metabolic pathways in the mitochondria of yeast to harness the precursor pools (i.e., pyruvate and acetyl‐CoA), bypass competing pathways, and minimize transportation limitations. However, only a few mitochondrial targeting sequences (MTSs) have been characterized (i.e., MTS of COX4), limiting the application of compartmentalization engineering for multigene biosynthetic pathways in the mitochondria of yeast. In the present study, based on the mitochondrial proteome, a total of 20 MTSs were cloned and the efficiency of these MTSs in targeting heterologous proteins, including the Escherichia coli FabI and enhanced green fluorescence protein (EGFP) into the mitochondria was evaluated by growth complementation and confocal microscopy. After systematic characterization, six of the well‐performed MTSs were chosen for the colocalization of complete biosynthetic pathways into the mitochondria. As proof of concept, the full α‐santalene biosynthetic pathway consisting of 10 expression cassettes capable of converting acetyl‐coA to α‐santalene was compartmentalized into the mitochondria, leading to a 3.7‐fold improvement in the production of α‐santalene. The newly characterized MTSs should contribute to the expanded metabolic engineering and synthetic biology toolbox for yeast mitochondrial compartmentalization engineering. [ABSTRACT FROM AUTHOR]

Despite clinical applications of the first‐generation tissue adhesives and hemostats, the correlation among microstructure and hemostasis of hydrogels with wound healing is less understood and it is elusive to design high‐performance hydrogels to meet worldwide growing demands in wound closure, hemostasis, and healing. Inspired by the microstructure of extracellular matrix and mussel‐mimetic chemistry, two kinds of coordinated and covalent glycopolypeptide hydrogels are fabricated, which present tunable tissue adhesion strength (14.6–83.9 kPa) and microporous structure (8–18 µm), and lower hemolysis <1.5%. Remarkably, the microporous size mainly controls the hemostasis, and those hydrogels with larger pores of 16–18 µm achieve the fastest hemostasis of ≈14 s and the lowest blood loss of ≈6% than fibrin glue and others. Moreover, both biocompatibility and hemostasis affect wound healing performance, as assessed by hemolysis, cytotoxicity, subcutaneous implantation, and hemostasis and healing assays. Importantly, the glycopolypeptide hydrogel‐treated rat‐skin defect model achieves full wound closure and regenerates thick dermis and epidermis with some hair follicles on day 14. Consequently, this work not only establishes a versatile method for constructing glycopolypeptide hydrogels with tunable adhesion and microporous structure, fast hemostasis, and superior healing functions, but also discloses a useful rationale for designing high‐performance hemostatic and healing hydrogels. [ABSTRACT FROM AUTHOR]

Background: Exposure to urban particulate matter (UPM) has been studied as a cause of various health problems. Although the association between UPM and the respiratory tract has been well studied, further research is required to characterize the effects of UPM on the upper respiratory tract. We investigated the effects of UPM‐induced reactive oxygen species (ROS) production on cultured human nasal fibroblasts, as well as the protective effects of α‐lipoic acid (ALA) on ROS production and the underlying signaling pathways involved in ROS inhibition. Methods: Human turbinate tissue specimens were collected from 6 patients. The effects of UPM on the viability of cultured nasal fibroblasts were determined. A fluorescent malondialdehyde assay was used to measure ROS levels. Real‐time reverse transcription polymerase chain reaction was used to measure the messenger RNA levels of genes encoding Nrf2, the antioxidant response elements (AREs) (HO‐1, NQO1), and the proinflammatory cytokines (interleukin‐6 and interleukin‐8) before and after ALA treatment. Western blotting analyses were used to measure nuclear and cytosolic Nrf2 and AREs. Results: UPM reduced cell viability and increased ROS expression in nasal fibroblasts. ALA treatment decreased ROS production in UPM‐exposed fibroblasts via the Nrf2, HO‐1, and NQO‐1 pathways. Also, ALA treatment abrogated increases in the interleukin‐6 and ‐8 levels induced by UPM in nasal fibroblasts. Conclusion: UPM exposure resulted in increased ROS production in nasal fibroblasts. ALA treatment inhibited this increase via the Nrf2 pathway, suggesting that ALA may have a protective effect against rhinitis caused by ROS expression induced by exposure to UPM. [ABSTRACT FROM AUTHOR]

In order to develop original water soluble antagonists of X‐linked inhibitor of apoptosis protein (XIAP), a novel bicyclic scaffold was designed based on 8,5‐fused bicyclic lactam. During its preparation, a spontaneous rearrangement from 8,5‐ to 7,5‐fused bicyclic lactam was observed and confirmed by MS and NMR analyses, in particular the HMBC spectra. DFT calculations were performed to understand the corresponding mechanism. It was finally prevented through changing the reaction order in the synthesis route and a Smac mimetic with this core structure, ZJ‐1 was successfully obtained. The structure of this new bicyclic scaffold was well confirmed by HRMS and NMR (1H, 13C, NOESY) analyses. ZJ‐1 presented in addition a binding affinity to XIAP‐BIR3, nearly 6 times better than that of AVPI, similar to the reported SM‐128 in an in vitro fluorescence polarization (FP) assay. This preliminary result suggests that this new bicyclic scaffold could be very attractive in the development of novel anticancer agents targeting XIAP. Beautiful, strong: A potent XIAP‐BIR3 antagonist was prepared by modification of a synthetic strategy to prevent 8,5‐fused bicyclic lactam, 5 from spontaneous rearrangement to form the 7,5‐fused 5'. DFT calculations were performed to understand the corresponding mechanism. [ABSTRACT FROM AUTHOR]

Background: Exposure to urban particulate matter (UPM) has been linked to aggravation of various health problems. Although the effects of UPM on the lower respiratory tract have been extensively studied, more research is required on the impact of UPM on the upper respiratory tract and the underlying mechanisms. Thus, we investigated the cytotoxic effects of UPM on cultured human nasal fibroblasts, the underlying signaling pathways involved, and changes in cytokine levels. Methods: Human turbinate tissue specimens were collected during partial turbinectomies performed on 6 patients, and then cultured. The effect of UPM on nasal fibroblast viability was explored. Real‐time reverse transcription‐polymerase chain reaction was used to measure the mRNA levels of genes encoding cytokines and chemokines (interleukin [IL]‐4, IL‐6, IL‐8, and tumor necrosis factor‐α) before and after 24 hours of UPM treatment. Enzyme‐linked immunosorbent assays were employed to measure IL‐6 and IL‐8 levels. The status of the p38 and nuclear factor (NF)‐κB signaling pathways was analyzed by Western blotting. Results: UPM reduced cell viability in a dose‐dependent manner and increased IL‐6 and IL‐8 expression at both the mRNA and protein levels. UPM induced the phosphorylation of p38 and NF‐κB p65; inhibitors of the actions of these proteins repressed phosphorylation and the expression of IL‐6 and IL‐8. Conclusion: UPM induced IL‐6 and IL‐8 expression by fibroblasts via p38 and NF‐κB classical signaling, suggesting that UPM can induce or aggravate allergic and/or chronic rhinitis. [ABSTRACT FROM AUTHOR]

ABSTRACT: Stimuli‐responsive polypeptides are receiving much attention for drug delivery systems and tissue engineering scaffolds; however, it is challenging to construct multiple‐responsive polypeptides and one‐component polymeric hydrogels. Herein, a novel type of triple redox/temperature‐responsive diselenide‐containing poly(methoxydiethylene glycol‐ l‐glutamate) homopolypeptide was facilely synthesized by selenocystamine‐initiated ring‐opening polymerization in DMF at 30 °C, and their chemical structures and physical properties were fully characterized by means of 1H NMR, GPC, FT‐IR, WAXD, and CD. They self‐assembled into spherical micelles in aqueous solution, which possess a lower critical solution temperature, redox‐responsiveness inherited from diselenide bond, and the triple stimuli‐sensitive self‐assembly behaviors, as characterized by means of turbidity, DLS, TEM, and zeta potential measurements. The diselenide‐containing homopolypeptides formed supramolecular hydrogels at room temperature, exhibiting a thermal gel–sol transition. The rheological tests evidence that the mechanical modulus of the hydrogel is independent of angular frequency within 100 rad/s and at 25 °C, in which the storage modulus of G′ is order of magnitude greater than the loss modulus of G″, displaying a solid‐like elastic behavior. Moreover, the mechanical modulus of the hydrogel can be tuned by changing the chain length of the homopolypeptide, the 10‐mM 1,4‐dithiothreitol (DTT) reduction, and 1 mM H2O2 oxidation, respectively. Consequently, this work provides a simple strategy to fabricate triple‐stimuli responsive polypeptide micelles and one‐component hydrogels. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1067–1077 [ABSTRACT FROM AUTHOR]

Heterogeneous catalysts of bifunctionality offer improved process efficiency and enhanced product yield in multistep chemical transformations conducted in a consecutive manner. However, this has seldom been realized in coprecipitated catalysts owing to the complexity of the synthesis. By adjusting the synthesis protocol of an industrial methanol-synthesis catalyst as a model system, herein we demonstrate the bifunctional effect of Al2O3/Cu/ZnO catalysts to enable the direct production of dimethyl ether from synthesis gas with yields that are 2-3-fold higher than those obtained with their conventional counterparts, with a greater number of accessible Cu surface atoms and more Al2O3 acid sites existing at the external particle surface. This is achieved by preparing the fully developed Cu,Zn precursor of a specific structure with surface-decorated Al species. Our approach paves the way towards the rational design of multicomponent precipitated catalysts with tunable bifunctionality for practical cascade reactions. [ABSTRACT FROM AUTHOR]

BACKGROUND The biomass-fired power in China is mainly fueled by agro-residue, and is suffering the bottlenecks of feedstock supply, super heater corrosion and nutrient cycle. How to recycle the ash nutrient to farmland is crucial for ecological sustainability. This work investigated potassium recovery from the fly ash of a grate boiler firing agro-residue using leaching methods. RESULTS The studied ash contains a massive amount of fixed carbon (158.92 mg g−1) and little volatile matter (39.44 mg g−1). The unburnt carbon strongly decreases the concentration ( CK) in the leachate and recovery percentage ( RPK) of potassium nutrient by 17.6-24.1% and 9.0-18.8%, respectively. Calcination pretreatment in air at 500 °C for 30 min should be employed before leaching to remove the unburnt carbon. Mineralogy analysis shows that low-temperature pre-calcination (≤575 °C) does not affect potassium solubility. Under the optimal leaching of calcined ash in water with liquid-to-solid ratio 3 for 30 min at room temperature, CK in the leachate, dissolution percentage ( DPK) and recovery percentage ( RPK) of potassium element reached 17.21 g L−1, 82.0%, and 62.6%, respectively. CONCLUSIONS The fly ash from grate boilers firing agro-residue is much better than other marginal potash sources. This work is helpful to improve the technology of agro-residue fired power. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

ABSTRACT Increasing evidence suggests that olfactory impairment is associated with an increased risk of conversion from mild cognitive impairment (MCI) to Alzheimer's disease. This study was to explore how olfactory identification relates to white matter (WM) integrity, using diffusion tensor imaging (DTI) in individuals with amnestic MCI. DTI was performed from nineteen individuals with amnestic MCI (mean age: 69.95 ± 8.20 years). Olfactory identification was assessed using the Cross-Cultural Smell Identification Test (CC-SIT), a widely used test for odor identification involving a scratch and sniff test of 12 micro-encapsulated odorants. Cross-sectional voxel-wise analyses of relationships between CC-SIT scores and DTI indices were performed using Tract-Based Spatial Statistics. Higher CC-SIT scores were associated with lower mean, axial and radial diffusivities in areas such as the body and splenium of corpus callosum, frontal WM (lateral orbitofrontal, caudal middle frontal, precentral, left superior frontal, and right pars opercularis), right superior longitudinal fasciculus, anterior and superior corona radiata, and internal and external capsules, while CC-SIT scores were not significantly associated with fractional anisotropy across all MCI participants. In individuals with amnestic MCI, impaired olfactory identification is associated with alterations in WM integrity expressed as a lower diffusivities value. This cross-sectional preliminary study suggests that olfactory impairment contributes to WM microstructural alterations in individuals with amnestic MCI. © 2016 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 26, 270-276, 2016 [ABSTRACT FROM AUTHOR]

Inspired by sweet or sugar-coated bullets that are used for medications in clinics and the structure and function of biological melanin, a novel kind of sweet polydopamine nanoparticles and their anticancer drug doxorubicin loaded counterparts are prepared, which integrate an active targeting function, photothermal therapy, and chemotherapy into one polymeric nanocarrier. The oxidative polymerization of lactosylated dopamine and/or with dopamine are performed under mild conditions and the resulting sweet nanoparticles are thoroughly characterized. When exposed to an 808 nm continuous-wave diode laser, the magnitude of temperature elevation not only increases with the concentration of nanoparticles, but can also be tuned by the laser power density. The nanoparticles possess strong near infrared light absorption, high photothermal conversion efficiency, and good photostability. The nanoparticles present tunable binding with RCA120 lectin and a targeting effect to HepG2 cells, confirmed by dynamic light scattering, turbidity analysis, MTT assay, and flow cytometry. Importantly, the sweet nanoparticles give the lowest IC50 value of 11.67 μg mL−1 for chemo-photothermal therapy compared with 43.19 μg mL−1 for single chemotherapy and 67.38 μg mL−1 for photothermal therapy alone, demonstrating a good synergistic effect for the combination therapy. [ABSTRACT FROM AUTHOR]

Background & Aims Accurate assessment of liver fibrosis in patients with chronic hepatitis B ( CHB) is necessary not only to predict the long-term clinical course but also to determine an appropriate antiviral therapy scheme. Several noninvasive approaches - serum markers and elastography - have been proposed as alternatives for the histopathological analysis of liver biopsies. The aim of this study was to evaluate two ultrasound elastography methods ( ARFI and TE) and one biochemical test ( APRI), as well as their optimal linear combination, in the assessment of liver fibrosis in CHB. Methods Ninety five patients with CHB and 16 volunteers underwent ARFI, TE and APRI; and liver fibrosis was staged in the patients by a liver biopsy. An optimal linear combination of the three methods was developed, and its diagnostic performance was evaluated by a 10-fold cross-validation. Results The accuracy of the linear combination was 83.86% and 91.88% for significant fibrosis (≥F2) and cirrhosis (F4), respectively, higher than those obtained for ARFI (83.50%, 88.76%), TE (75.27%, 87.61%) and APRI (73.29% and 81.67%). The combination also increased the sensitivity and the negative predictive values for the diagnosis of significant fibrosis and cirrhosis. Conclusions The optimal linear combination algorithm is effective for noninvasive staging of liver fibrosis in CHB. However, linear combination has its own limitations; nonlinear methods may eventually reveal even clearer diagnostic results. [ABSTRACT FROM AUTHOR]

The biodegradable polymeric nanomedicines that may be integrated with multi-stimuli-sensitivity to achieve triggered or on-demand drug release kinetics are challenging for polymer therapeutics and drug delivery systems. By controlling the structure transformation of one polypeptide- b-PEO copolymer, a novel multi-responsive polypeptide-based vesicle (polypeptidosome) presents the combined sensitivity of multiple physiological and clinic-related stimuli, and both morphology and size of the polypeptidosome are changed during the triggered process. The designer polypeptide has unique structures composed of 1) light-responsive o-nitrobenzyl groups, 2) oxidizable thioether linkers, 3) photo-caged redox thiol groups on parent poly(L-cysteine), and 4) tunable conformation, which enable the polypeptidosome to have a peculiar multi-response. The anticancer drug doxorubicin can be released in a controlled or on-off manner. The combination stimuli of UV irradiation and H2O2 oxidation induces a large effect and a lower IC50 of 3.80 μg doxorubicin (DOX) equiv/mL compared to 5.28 μg DOX equiv/mL of individual H2O2 trigger. [ABSTRACT FROM AUTHOR]

In this study, we apply flexible Fourier stationary unit root test proposed by Enders and Lee (2012) to assess the non-stationary properties of the per capita real gross domestic product ( GDP) for 32 African countries. We find that Fourier stationary unit root test has higher power than linear method if the true data-generating process of per capita real GDP is in fact a stationary nonlinear process of an unknown form with structural change using the low frequency components. We investigate the stationarity of per capita real GDP from the nonlinear point of view and provide robust evidence that clearly indicates that real output is well characterised by a nonlinear, mean-reverting process, namely Benin, Botswana, Burundi, Cameroon, Senegal, Sierra Leone and South Africa. Our evidence points that these seven countries are nonlinear stationary, implying that per capita real GDP follows a steady rate of growth, and policy innovations then have temporary effects. These results have important policy implications for African countries. [ABSTRACT FROM AUTHOR]

ABSTRACT Disulfide-centered star-shaped poly(ε-benzyloxycarbonyl- l-lysine)- b-poly(ethylene oxide) block copolymers (i.e., A2B4 type Cy-PZlys- b-PEO) were synthesized by the combination of ring-opening polymerization and thiol-yne chemistry. Their molecular structures and physical properties were characterized in detail by FTIR, 1H NMR, gel permeation chromatography, differential scanning calorimetry, wide-angle X-ray diffraction, and polarized optical microscope. Despite mainly exhibiting an α-helix conformation, the inner PZlys blocks within copolymers greatly prohibited the crystallinity of the outer PEO blocks and presented a liquid crystal phase transition behavior in solid state. These block copolymers Cy-PZlys- b-PEO self-assembled into nearly spherical micelles in aqueous solution, which had a hydrophobic disulfide-centered PZlys core surrounded by a hydrophilic PEO corona. As monitored by means of DLS and TEM, these micelles were progressively reduced to smaller micelles in 10 mM 1,4-dithiothreitol at 37 °C and finally became ones with a half size, demonstrating a reduction-sensitivity. Despite a good drug-loading property, the DOX-loaded micelles of Cy-PZlys- b-PEO exhibited a reduction-triggered drug release profile with an improved burst-release behavior compared with the linear counterpart. Importantly, this work provides a versatile strategy for the synthesis of the disulfide-centered star-shaped polypeptide block copolymers potential for intracellular glutathione-triggered drug delivery systems. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 2000-2010 [ABSTRACT FROM AUTHOR]

The three-dimensional coordination polymer poly[[bis(μ3-2-aminoacetato)di-μ-aqua-μ3-(naphthalene-1,5-disulfonato)-hexasilver(I)] dihydrate], {[Ag6(C10H6O6S2)(C2H4NO2)4(H2O)2]·2H2O} n, based on mixed naphthalene-1,5-disulfonate ( L1) and 2-aminoacetate ( L2) ligands, contains two AgI centres (Ag1 and Ag4) in general positions, and another two (Ag2 and Ag3) on inversion centres. Ag1 is five-coordinated by three O atoms from one L1 anion, one L2 anion and one water molecule, one N atom from one L2 anion and one AgI cation in a distorted trigonal-bipyramidal coordination geometry. Ag2 is surrounded by four O atoms from two L2 anions and two water molecules, and two AgI cations in a slightly octahedral coordination geometry. Ag3 is four-coordinated by two O atoms from two L2 anions and two AgI cations in a slightly distorted square geometry, while Ag4 is also four-coordinated by two O atoms from one L1 and one L2 ligand, one N atom from another L2 anion, and one AgI cation, exhibiting a distorted tetrahedral coordination geometry. In the crystal structure, there are two one-dimensional chains nearly perpendicular to one another (interchain angle = 87.0°). The chains are connected by water molecules to give a two-dimensional layer, and the layers are further bridged by L1 anions to generate a novel three-dimensional framework. Moreover, hydrogen-bonding interactions consolidate the network. [ABSTRACT FROM AUTHOR]

The Tup fragments of tubulysins were synthesized with a tandem reaction as the key step, and unexpected diastereoselectivity was observed in the first Grignard addition stage. The coupling of the enolate of a thiazolyl ketone with chiral sulfinimines furnished the backbone of the Tuv fragment with over 100:1 d.r. and high yield. Thus, tubulysin U and C-4 epi-tubulysin U were prepared in a highly selective and efficient manner. The results of the MTT assay furthermore indicated that C-4 epi-tubulysin U maintained significant growth inhibition activities against several cancer cell lines. [ABSTRACT FROM AUTHOR]

Objectives/hypothesis: To evaluate the relationship between subjective symptoms of nasal obstruction and the corresponding nasal anatomical parameters using paranasal computed tomography (PNS CT). Study Design: Retrospective chart review at a tertiary referral center. Methods: We studied 277 patients who underwent evaluation by the Nasal Obstruction Symptom Evaluation scale and a visual analogue scale of nasal obstruction for preoperative evaluation; 197 patients with nasal obstruction who underwent septoplasty were enrolled in the study group, and 80 patients without nasal septal deviation and without nasal obstruction who underwent a trans-sphenoidal pituitary tumor operation were enrolled in the control group. A preoperative coronal CT image was used to calculate both nasal cavity cross-sectional areas and the septal deviation angle at the three levels (internal nasal valve, ostiomeatal unit [OMU], and choana). Results: Differences between the study group and the control group were found in all nasal anatomical parameters at the internal nasal valve, OMU, and choana. In the study group, subjective nasal obstruction symptoms were correlated with the septal deviation angle and the nasal cavity cross-sectional area at the OMU and the choana levels. However, there was no correlation between subjective symptoms of nasal obstruction and anatomical factors at the nasal valve level (P < .05). Conclusions: Coronal PNS CT revealed a relationship between subjective nasal obstructive symptoms and anatomical factors at the middle and posterior nasal levels, especially in patients complaining of stuffy nose. When septoplasty is performed, we must pay attention to correction of middle and posterior nasal septal deviation. [ABSTRACT FROM AUTHOR]

Objectives/Hypothesis To evaluate the relationship between subjective symptoms of nasal obstruction and the corresponding nasal anatomical parameters using paranasal computed tomography (PNS CT). Study Design Retrospective chart review at a tertiary referral center. Methods We studied 277 patients who underwent evaluation by the Nasal Obstruction Symptom Evaluation scale and a visual analogue scale of nasal obstruction for preoperative evaluation; 197 patients with nasal obstruction who underwent septoplasty were enrolled in the study group, and 80 patients without nasal septal deviation and without nasal obstruction who underwent a trans-sphenoidal pituitary tumor operation were enrolled in the control group. A preoperative coronal CT image was used to calculate both nasal cavity cross-sectional areas and the septal deviation angle at the three levels (internal nasal valve, ostiomeatal unit [OMU], and choana). Results Differences between the study group and the control group were found in all nasal anatomical parameters at the internal nasal valve, OMU, and choana. In the study group, subjective nasal obstruction symptoms were correlated with the septal deviation angle and the nasal cavity cross-sectional area at the OMU and the choana levels. However, there was no correlation between subjective symptoms of nasal obstruction and anatomical factors at the nasal valve level ( P < .05). Conclusions Coronal PNS CT revealed a relationship between subjective nasal obstructive symptoms and anatomical factors at the middle and posterior nasal levels, especially in patients complaining of stuffy nose. When septoplasty is performed, we must pay attention to correction of middle and posterior nasal septal deviation. Level of Evidence 3. [ABSTRACT FROM AUTHOR]

Thermosensitive diethylene glycol-derived poly( L-glutamate) homopolypeptides (i.e., poly- L-EG2-Glu) with different molecular weights (MW) ( Mn,GPC = 5380-32520) were synthesized via the ring-opening polymerization (ROP) of EG2- L-glutamate N-carboxyanhydride (EG2-Glu-NCA) in N, N-dimethylformamide solution at 50 °C. Their molecular structure, conformation transition, liquid crystal (LC) phase behavior, lower critical solution temperature (LCST) transition, and morphology evolution were thoroughly characterized by means of FTIR, 1H NMR, gel permeation chromatography, differential scanning calorimetry, wide angle X-ray diffraction, polarized optical microscope, transmission electron microscope, and dynamic light scattering. In solid state, the homopolypeptide poly- L-EG2-Glu presented a conformation transition from α-helix to β-sheet with increasing their MW at room temperature, while it mainly assumed an α-helix of 80-86% in aqueous solution. Poly- L-EG2-Glu showed a thermotropic LC phase with a transition temperature of about 100 °C in solid state, while it gave a reversible LCST transition of 34-36 °C in aqueous solution. The amphiphilic homopolypeptide poly- L-EG2-Glu self-assembled into nanostructures in aqueous solution, and their critical aggregation concentrations decreased with increasing MW. Interestingly, their morphology changed from spherical micelles to worm-like micelles, then to fiber micelles with increasing MW. This work provides a simple method for the generation of different nanostructures from a thermosensitive biodegradable homopolypeptide. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

Bioreducible and core-crosslinked hybrid micelles were for the first time fabricated from biodegradable and biocompatible trimethoxysilyl-terminated and disulfide-bond-linked block copolymers poly(ε-caprolactone)-S-S-poly(ethylene oxide), which were prepared by combining thiol-ene coupling reaction and ring-opening polymerization. The molecular structures, physicochemical, self-assembly, and bioreducible properties of these copolymers were thoroughly characterized by means of FTIR, 1H NMR, gel permeation chromatography, differential scanning calorimetry, wide-angle X-ray diffraction, dynamic light scattering (DLS), and transmission electron microscopy. The core-crosslinking sol-gel reaction was confirmed by 1H NMR, and the core-crosslinked hybrid micelles contained about 3 wt % of silica. The bioreducible property of both uncrosslinked and core-crosslinked micelles in 10 mM 1,4-dithiothreitol (DTT) solution was monitored by DLS, which demonstrated that the PEO corona gradually shedded from the PCL core. The anticancer doxorubicin drug-loaded micelles showed nearly spherical morphology compared with blank micelles, presenting a DTT reduction-triggered drug-release profile at 37 °C. Notably, the core-crosslinked hybrid micelles showed about twofold drug loading capacities and a half drug-release rate compared with the uncross-liked counterparts. This work provides a useful platform for the fabrication of bioreducible and core-crosslinked hybrid micelles potential for anticancer drug delivery system. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

Dendron-like poly(ε-benzyloxycarbonyl- L-lysine)/linear poly(ethylene oxide) block copolymers (i.e., Dm-PZLys- b-PEO, m = 0 and 3; Dm are the propargyl focal point poly(amido amine) dendrons having 2m primary amine groups) were for the first time synthesized by combining ring-opening polymerization (ROP) of ε-benzyloxycarbonyl- L-lysine N-carboxyanhydride (Z-Lys-NCA) and click chemistry, where Dm-PZLys homopolypeptides were click conjugated with azide-terminated PEO. Their molecular structures and physical properties were characterized in detail by FTIR, 1H NMR, gel permeation chromatography, differential scanning calorimetry, polarized optical microscopy, and wide angle X-ray diffraction. Both homopolypeptides and copolymers presented a liquid crystalline phase transition for PZLys block, and the transition was irreversible. Moreover, the degree of crystallinity of PEO block within linear copolymers decreased from 96.2% to 20.4% with increasing PZLys composition, whereas that within dendritic copolymers decreased to zero. The secondary conformation of PZLys progressively changed from β-sheet to α-helix with increasing the chain length. These copolymers self-assembled into spherical nanoparticles in aqueous solution, and the anticancer drug doxorubicin-loaded nanoparticles gave a similar morphology compared with their blank counterparts. The drug-loaded nanoparticles showed a triphasic drug-release profile at aqueous pH 7.4 or 5.5 and 37 °C and sustained a longer drug-release period for about 2 months. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 [ABSTRACT FROM AUTHOR]

Dendron-like/dendron-like poly(ε-caprolactone)- b-poly(γ-benzyl- L-glutamate) block copolymers with asymmetrical topology (PCL [ABSTRACT FROM AUTHOR]

Whether administration of total alkaloids from Commelina communis L. (TAC) reduces lung damage in influenza virus-infected mice was investigated. Compared with untreated mice, significantly less severe damage was found in the lungs of mice administered TAC at 8 mg/kg per day for 6 days. TAC significantly decreased viral loads in the lungs. The concentrations of IFN-γ in the serum of TAC-treated mice were significantly lower than those of virus control mice at 4 and 6 days post-infection. The results indicate that TAC imparted partial protection to the mice by reducing pulmonary viral loads and limiting lesions in the lungs. [ABSTRACT FROM AUTHOR]

Cocaine use may cause coronary artery spasm and acute myocardial ischaemia/infarction. However, its effects on ATP-sensitive K+ (KATP) channel, an ion channel responsible for ischaemic preconditioning, remain unknown. In isolated rat ventricular myocytes with whole-cell experiments, cocaine can reverse action potential shortening and increased K+ current caused by the openers of ATP-sensitive K+ (KATP) channels. In inside-out patches, cocaine applied to intracellular surface suppressed KATP-channel activity in a concentration-dependent manner with an IC50 value of 9.2 μM; however, it did not modify the single-channel conductance of this channel. The change in the kinetic behaviour of KATP channels caused by cocaine is primarily the result of an increase in mean closed time and a decrease in mean open time. Cocaine-induced inhibition of KATP channels is independent of change in intracellular ATP concentrations. In heart-derived H9c2 cells, cocaine is also capable of suppressing KATP-channel activity. The present study provides evidence that cocaine can produce a depressant action on KATP channels in cardiac myocytes, and thus disturb ischaemic preconditioning in clinical settings. [ABSTRACT FROM AUTHOR]

The Boredetella pertussis wlbD gene product is a putative uridine- 5-diphosphate N-acetylglucosamine (UDP-G1cNAc) 2' -epimerase involved in Band A lipopolysaccharide biosynthesis. The wlbD gene is homologous to Escherichia coli rffE (32% identical), an established UDP-G1cNAc 2'-epimerase that is involved in enterobacterial common antigen (ECA) formation. The structure of the rffE protein reveals an unexpected role for a bound sodium ion in orientating a substrate-binding a-helix in the enzyme active site. Whilst key active- site residues in rffE are present in the wlbD sequence, the sodium- binding residues outside the active site are absent. This raises questions about the modulation of enzyme activity in these two enzymes. The wlbD gene from B. pertussis has been cloned and overexpressed in E. coli and the resulting protein has been purified to homogeneity. In the current study, crystals of the mutant Gln339Arg wlbD enzyme have been obtained by sitting-drop vapour diffusion. Uncomplexed Gln339Arg and UDP-G1cNAc complex data sets have been collected in-house on a rotating-anode generator to 2.1 A. Combined, the data sets identify the space group as P212121, with unit-cell parameters a = 78, b = 91, c = 125 Å, α = β = γ = 90°. The asymmetric unit contains two monomers and 53% solvent. [ABSTRACT FROM AUTHOR]

Zn anodes in aqueous zinc‐ion batteries chronically suffer from pernicious side reactions and ineluctable dendrite growth, resulting in inadequate reversibility and suboptimal Coulombic efficiency (CE) and impeding commercialization. Herein, a multifunctional metal–organic coordination polymer layer (FAZ) is constructed on the zinc anode surface (FAZ@Zn) utilizing a simple self‐assembly strategy. The zincophilic FAZ interfacial layer with a high Zn2+ transfer number and low nucleation barrier effectively facilitates the de‐solvation process, supports the rapid transport of zinc ions, and contributes to the preferential growth of Zn (002) crystal planes, enabling dendrite‐free Zn deposition. Furthermore, the FAZ layer, as an interfacial pH regulating layer, effectively inhibits the direct contact between Zn and active water molecules, lowering the severity of side reactions. Consequently, the FAZ@Zn anode furnishes an eminent cycle stability over 6900 h, with a low polarization voltage at 1 mA cm−2 and 1 mA h cm−2 and a boosted CE of 99.88% over 4100 cycles. More encouragingly, when coupled with Na2V6O16·3H2O, the FAZ@Zn anode enables the full cell to deliver satisfactory rate performance and a 97% capacity retention over 1600 cycles. This work provides a simple strategy for the effective preparation of highly reversible zinc anodes for high‐performance aqueous zinc‐ion batteries. [ABSTRACT FROM AUTHOR]