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A heterocycle containing phosphorus, known as dialkyl‐2H‐1,2‐phosphasiliren‐3‐olate 2, is synthesized through the reaction of dialkylsilylene 1 and sodium phosphaethynolate (NaOCP) in a high yield at ambient conditions. The structure of 2 is determined by single‐crystal X‐ray diffraction and multinuclear NMR spectroscopy. The theoretical studies are identified two nucleophilic centres located on the phosphorus (P) and oxygen (O) atoms, respectively. According to WBIs and the crystal characterization analyses, both the C−P and C−O bonds in the C−Si‐P three‐membered ring have significant double bond character. Reactions involving R3SiCl and Me2SO4 with 2 at room temperature are also conducted at room temperature. The nucleophilic substitution reaction can also occur on oxygen atom of 2, and yield ring‐retaining products 3 and 4 a–4 c, respectively. When acyl chlorides are employed as electrophiles, the derivatives of (silylmethylidyne)phosphane, 6 a–6 c, are produced as a result of the substitution of the oxygen atom. [ABSTRACT FROM AUTHOR]

Pyroptosis is a recently defined form of immunogenic cell death that shows great promise in cancer immunotherapy. However, almost all small‐molecule pyroptosis‐inducing agents (PyAs) reported to date indiscriminately induce pyroptosis in multiple cell types, leading to off‐target pyroptotic death of normal and immune cells. One promising approach to addressing this biosafety issue is the design of conditionally activatable PyAs that specifically respond to disease biomarkers. Herein, a general solution for facilely tailoring and synthesizing activatable PyAs based on a newly developed class of photoactive PyAs, termed PyPSs, is reported. The unique structurally encoded properties of PyPSs, including endo reticulum targeting, hypoxia tolerance, and sensing properties, excitingly meet a demanding set of performance requirements for constructing conditionally activatable PyAs for cancer immunotherapy. Based on PyPS‐1 scaffold, hypoxia‐activatable PyPS‐NF as a proof‐of‐concept example is prepared, demonstrating specific hypoxia‐activated pyroptotic cell death and favorable immunotherapeutic efficacy of solid tumors. Herein, a general design strategy for tailoring activatable PyAs to precisely control GSDME‐mediated cell pyroptosis is established, with great potential to advance cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Background: Currently, many stemness-related signatures have been developed for gastric cancer (GC) to predict prognosis and immunotherapy outcomes. However, due to batch effects, these signatures cannot accurately analyze patients one by one, rendering them impractical in real clinical scenarios. Therefore, we aimed to develop an individualized and clinically applicable signature based on GC stemness. Methods: Malignant epithelial cells from single-cell RNA-Seq data of GC were used to identify stemness-related signature genes based on the CytoTRACE score. Using two bulk tissue datasets as training data, the enrichment scores of the signature genes were applied to classify samples into two subtypes. Then, using the identified subtypes as criteria, we developed an individualized stemness-related signature based on the within-sample relative expression orderings of genes. Results: We identified 175 stemness-related signature genes, which exhibited significantly higher AUCell scores in poorly differentiated GCs compared to differentiated GCs. In training datasets, GC samples were classified into two subtypes with significantly different survival times and genomic characteristics. Utilizing the two subtypes, an individualized signature was constructed containing 47 gene pairs. In four independent testing datasets, GC samples classified as high risk exhibited significantly shorter survival times, higher infiltration of M2 macrophages, and lower immune responses compared to low-risk samples. Moreover, the potential therapeutic targets and corresponding drugs were identified for the high-risk group, such as CD248 targeted by ontuxizumab. Conclusions: We developed an individualized stemness-related signature, which can accurately predict the prognosis and efficacy of immunotherapy for each GC sample. [ABSTRACT FROM AUTHOR]

Background: As adequate support, virtual reality (VR) has been increasingly introduced into the classroom to help students learn a new language. However, empirical studies exploring the educational potential of using 360° spherical video‐based virtual reality (SVVR) in high‐school Chinese language classrooms are still lacking. Objectives: A mind mapping‐based SVVR learning system is proposed for international high‐school students' Chinese courses and examines its effects on improving Chinese learning achievements and perceptions among Grade 10 students who learn Chinese as a foreign language. Methods: This study adopted a quasi‐experiment design. Participants (N = 66) were assigned to one of three conditions: mind mapping‐based SVVR (MMBSVVR), conventional SVVR (CSVVR), or traditional lecturing (TL). Our mixed‐method approach employed pre‐and post‐tests to measure Chinese learning achievements, questionnaires to measure Chinese learning motivation, problem‐solving ability, and self‐efficacy, and semi‐structured interviews to further explore students' feelings and attitudes about Chinese courses in corresponding learning environments. Results and Conclusions: The results showed that the MMBSVVR classroom significantly improved high students' Chinese learning achievements in Chinese vocabulary and making sentence, problem‐solving ability, and self‐efficacy. Moreover, SVVR stimulates students' learning interest and class participation, and mind mapping provides students with a clear guide to arrange the knowledge. These findings help interpret the relationships between MMBSVVR and learning achievements, Chinese learning motivation, problem‐solving ability, and self‐efficacy in an international high school Chinese courses, thus providing insight on integrating MMBSVVR into existing classrooms. Lay Description: What is Already Known about this Topic: By creating fully immersive 3D environments, 360° spherical video‐based virtual reality (SVVR) in promoting language learning has been confirmed by many scholars with a focus on English language learning.Mind mapping effectively enables second language learners to review and retain new words in the target language meaningfully. Also, it can create a more vivid learning atmosphere through images and graphics and promote learners' memory and learning motivation. What This Paper Adds: A mind mapping‐based SVVR learning system has been developed with the support of the constructivism theory.A mind mapping‐based SVVR learning system is proposed to facilitate international students' Chinese learning performance in Chinese vocabulary acquisition and sentence construction.In addition to promoting international students' learning outcomes, the proposed approach indicated promising results in learning motivation, problem‐solving ability, and self‐efficacy. Implications for Practice and/or Policy: This study provides an evidence base for further research through the utilization of VR learning environments in Chinese language classrooms.This study advocates introducing SVVR technology in the Chinese learning classrooms to increase the learning context for international students. It is also worth encouraging scholars to design VR learning systems with different learning strategies.Due to the cognitive requirements of the Chinese language learning process, it is necessary to introduce mind maps in the SVVR learning system to assist students in constructing knowledge and combining prior and new knowledge to generate long‐term memory. [ABSTRACT FROM AUTHOR]

Taking supersaturation and heat transfer rate as evaluation indexes, two typical internal geometries of an oscillatory flow crystallizer (OFC) with circular‐orifice baffles (OFC‐COB) and smooth periodic constrictions (OFC‐SPC) were studied by numerical simulation. The results indicated that OFC‐SPC could provide a relatively high heat transfer rate, supersaturation, and similar or lower power density consumption, as well as a uniform flow field distribution without vortex dead zone. Further, a method to prejudge the supersaturation in oscillatory flow crystallizer is proposed, which would be good guidance to determining the operating parameters. [ABSTRACT FROM AUTHOR]

The article titled "Cover Feature: Synthesis and reactivity of a dialkyl-2H-1,2-phosphasiliren-3-olate" in the European Journal of Inorganic Chemistry showcases a traditional Chinese cultural symbol called Shuanglong Xizhu, which represents auspiciousness, majesty, and strength. The picture also celebrates the Chinese New Year, specifically the "Year of the Dragon," which is a symbol of China. The two dragons in the picture represent nucleophilic centers on the P and O atoms, respectively, and interact around a "pearl" formed from the substrates. The article provides more information on the molecular structure and can be found in the Research Article by L. Wang, Z. Li, and co-workers. [Extracted from the article]

The ageing of orchards is common in the apple planting process, which affects the yield and quality of apples, as well as the development of the apple industry and local economy. The investigation of soil properties is important to the improvement and soil management of aged apple orchards. In this study, we investigated the spatial distribution, correlation and clustering of soil properties (nutrients, pH, enzymes and microorganisms) in aged and non‐aged apple orchards, as well as soil microbial communities in aged orchards with and without biofertilizer (Bacillus mucilaginosus + N, P, K) in Luochuan, Loess Plateau. The results showed that most soil properties, except for pH and catalase activity, decreased gradually with depth of soil and were highest in the 0–40 cm layer in both the aged and non‐aged orchards. However, there were no obvious differences in the horizontal direction, especially in the aged orchards, indicating that the fertilizer application site was randomly located in the aged orchards. The significant correlations between soil nutrients and microbes, available phosphorus and tree age, and the clustering of orchards as aged and non‐aged groups by soil properties, indicated that soil properties should be monitored in a timely manner to assess fertilizer application and predict the ageing of orchards. Additionally, the biofertilizer might make the aged orchard soil tend to non‐ageing by increasing beneficial and reducing harmful microbes, which suggested that biofertilizers should be widely used in future fertilizer application management of aged orchards to delay ageing. [ABSTRACT FROM AUTHOR]

In this paper, the compound (E)‐N‐(3,5‐dimethylphenyl)‐2‐(3‐chlorobenzylidene)thiosemicarb‐azone was synthesized and characterized by elemental analysis, Fourier transform infrared (FT‐IR), 1H nuclear magnetic resonance (NMR), 13C NMR. The crystal structure was determined by single‐crystal X‐ray diffraction tool, indicating that the compound belongs to the orthorhombic crystal system of the Fdd2 space group, where a = 14.0472(12) Å, b = 57.148(4) Å, c = 7.9633(6) Å, the chemical formula is C16H16ClN3S, Mr = 317.83, V = 6392.7(9) Å3, Z = 16, Dc = 1.321 Mg/m3, F(000) = 2656, R = 0.0339, wR = 0.0903. Analysis of crystal data shows that the molecular conformation has good planarity. Hirshfeld surface and two‐dimensional (2D) fingerprints were used to analyze the intermolecular hydrogen bonds. In addition, a more comprehensive theoretical calculation studies were carried out on synthetic compound, such as potential energy surface (PES) scan, reduced density gradient (RDG), and independent gradient model (IGM) analysis, atoms in molecules (AIM) analysis, highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) and UV‐visible spectra analysis. The combination of experimental and theoretical data proved that non‐covalent bonds play a vital role in maintaining the stability of molecule. Finally, molecular docking was used to research the interaction between the synthetic compound and the receptor protein (4C2L). Meanwhile, the results obtained by in vitro antifungal assay indicated that the synthetic compound possesses the most remarkable inhibitory effect for Fusarium graminearum. [ABSTRACT FROM AUTHOR]

Two novel thiosemicarbazone derivatives (E)‐N‐(3,5‐dimethylphenyl)‐2‐(3‐methylbenzylidene)thiosemicar‐bazone (1) and (E)‐N‐(3,5‐dimethylphenyl)‐2‐(3‐fluorobenzylidene)thiosemicarbazone (2) had been synthesized and characterized by FT‐IR, nuclear magnetic resonance, and elemental analysis. Single crystal X‐ray diffraction analysis showed that compound 1 belongs to triclinic system in P‐1 space group and compound 2 belongs to monoclinic system in C2/c space group. It could be seen from the determined crystal structure that the central skeleton NNHC(S)NH of both thiosemicarbazone compounds have good planarity. Density functional theory (DFT) calculations were done using B3LYP/6‐31+G(d, p) basis set and the calculated results are in good agreement with the experimental data. In addition, the UV‐visible absorption spectrum was estimated based on TD‐DFT quantum chemistry calculations. Likewise, the simulated absorption spectrum is very consistent with the experimental data. Combining Hirshfeld surface analysis and molecular structure, it was found that the intermolecular hydrogen bond NH···SC constitutes central symmetric dimer S228. Through quantum chemical calculation, we investigated the reduced density gradient function and the independent gradient model, which provided a deeper insight into the intermolecular and intramolecular interaction force of the compounds. The frontier molecular orbital analysis and molecular electrostatic potential were also discussed by theoretical calculations. [ABSTRACT FROM AUTHOR]

Lung cancer is one of the greatest threats to human health, and is initially detected and attacked by the immune system through tumor‐reactive T cells. The aim of this study was to determine the basic characteristics and clinical significance of the peripheral blood T‐cell receptor (TCR) repertoire in patients with advanced lung cancer. To comprehensively profile the TCR repertoire, high‐throughput sequencing was used to identify hypervariable rearrangements of complementarity determining region 3 (CDR3) of the TCR β chain in peripheral blood samples from 64 advanced lung cancer patients and 31 healthy controls. We found that the TCR repertoire differed substantially between lung cancer patients and healthy controls in terms of CDR3 clonotype, diversity, V/J segment usage, and sequence. Specifically, baseline diversity correlated with several clinical characteristics, and high diversity reflected a better immune status. Dynamic detection of the TCR repertoire during anticancer treatment was useful for prognosis. Both increased diversity and high overlap rate between the pre‐ and post‐treatment TCR repertoires indicated clinical benefit. Combination of the diversity and overlap rate was used to categorize patients into immune improved or immune worsened groups and demonstrated enhanced prognostic significance. In conclusion, TCR repertoire analysis served as a useful indicator of disease development and prognosis in advanced lung cancer and may be utilized to direct future immunotherapy. What's new? T cells are essential players in the anti‐cancer immune response. Characterization of the T‐cell receptor (TCR) repertoire is a promising method for assessing tumor activity, directing therapy, and predicting prognosis; however, the importance of the TCR repertoire in lung cancer is unclear. This sequencing analysis found that the peripheral blood TCR repertoire of patients with advanced lung cancer was significantly different from that of healthy individuals. The peripheral blood TCR repertoire correlated with several clinical characteristics and patient immune status. Dynamic TCR repertoire analysis served as a useful indicator of disease development and may be utilized to direct future immunotherapy. [ABSTRACT FROM AUTHOR]

The synthesis of polyurea via the addition of carbon dioxide (CO2) to a diamine of 4,7,10‐trioxa‐1,13‐tridecanediamine (TOTDDA) was investigated by using organic and inorganic base catalysts. It was found that 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) was the most active among the catalysts examined. The influence of CO2 pressure, temperature, and reaction time was examined for the DBU‐catalyzed polyurea synthesis. The reaction mixture was analyzed by in situ high‐pressure attenuated total reflectance Fourier‐transform infrared spectroscopy (ATR‐FTIR) under reaction conditions, and possible reaction mechanisms, in which DBU can activate both CO2 and TOTDDA, were proposed. Physicochemical properties of polyurea materials synthesized were examined by several techniques. In addition, the catalytic performance of DBU was further examined for the addition of CO2 to other different diamine compounds. [ABSTRACT FROM AUTHOR]

BACKGROUND: Plant viral diseases cause tremendous decreases in yield and quality. Natural polycyclic compounds such as those containing carbocycles are often very important lead compounds for drug and pesticide development. Tricyclic spiranoid lactones with 5A5B6C‐ring fusion topologies possess various bioactivities. In this study, 33 new 5A5B6C tricyclic spirolactones were rationally designed, synthesized, characterized and evaluated for antiviral activities. RESULT: These compounds showed no apparent toxicity against Italian honeybees up to 2.73 µg bee−1. Spirolactones 14, 16, 19, 23 and 28 at a concentration of 100 µg mL−1 inactivated 90% of tobacco mosaic virus (TMV) infection, making these compounds much more potent than the positive controls. Significantly, compound 19 displayed the best inactivation activity causing inhibition of up to 98%. CONCLUSION: The results of the bioassays and QSAR studies indicated that the carbon‐containing cyclic moiety was the antiviral pharmacophore, and derivative 19, which showed the best inactivation activity, could emerge as a potential antiviral agent against TMV. In vitro capsid protein (CP) assembly and TMV assembly inhibition determinations indicated that these compounds induced crosslinking in the TMV and prevented its uncoating, which was a putative new mode of action for TMV inactivation. © 2018 Society of Chemical Industry Plant viruses often drastically damage crops and cause serious reductions in crop yield and quality. To control viral damage, this article designed and synthesized a series of 5A5B6C tricyclic spirolactones for evaluation of anti‐viral potencies. Bioassays indicated that 5A5B6C fused tricyclic spirolactone was an effective antivirus lead compound deserving of future studies and a QSAR model was developed to explain and predict the activity of these compounds. It is the first time we discovered its anti‐TMV activity. Moreover, to find its mode of action, molecular biological studies were conducted. The results proved that these compounds prevented the uncoating of TMV, which was a putative novel mode of action for plant virus control. [ABSTRACT FROM AUTHOR]

Abstract: Ultimate pH (pHu) is a major determinant factor of meat quality. In this study, we investigated the effects of pHu on the muscle antioxidant capacity, and the relationship between pHu and muscle antioxidant capacity of pigs. A total of 137 pigs from three pig breeds with the same feeding condition were slaughtered and used to measure the pHu, superoxide dismutase (SOD), glutathione peroxidase (GSH‐PX), total antioxidant capacity (T‐AOC), and malondialdehyde (MDA) content, and gene expression of SOD1 and GPX4. Loins from 137 pigs of three breeds were classified based on pHu into three groups: low (L‐pH: ≤5.50), intermediate (I‐pH: 5.51‐5.90), and high (H‐pH: ≥5.91). A majority of loins (47.5%–52%) were classified into the intermediate group. The results suggested that the pHu value was correlated with the activity of SOD, GSH‐PX, T‐AOC, and MDA, and gene expression of SOD1 and GPX4 in all pigs. In addition, our results also indicated a linear relationship between the pHu value and antioxidant traits. The pHu value accounted for 23%–40% of the variation in the antioxidant traits. These results suggested that increased pHu reduce the lipid peroxidation, and also indicated that pHu may be a key factor explaining the variation in the activity of antioxidant enzymes and gene expression in pork loins. [ABSTRACT FROM AUTHOR]

An external-cavity diode laser for 1550-nm wavelength is reported with ultra-low noise, high power coupled to a fiber, and fast tunability. These characteristics enable the generation of an optical frequency comb in a silica micro-resonator with a single-soliton state. Neither an optical amplifier nor a modulator is used in the experiment. This demonstration greatly simplifies the soliton generation setup and represents a significant step forward to a fully integrated soliton comb system. [ABSTRACT FROM AUTHOR]

Subset heterogeneity of the mononuclear phagocyte system ( MPS) is controlled by defined transcriptional networks and programs; however, the dynamic establishment of programs that control broad, orchestrated expression of transcription factors ( TFs) during the progression of monocyte-into-phagocyte ( MP) differentiation remains largely unexplored. By using chromatin immunoprecipitation assays, we show the extensive trimethylation of histone H3 lysine 4 (H3K4me3) as well as histone H3 lysine 27 (H3K27me3) occupancy with broad footprints at the promoters of MP differentiation-related TFs, such as HOXA and FOXO genes, KLF4, IRF8 and others. The rapid repression of HOXA genes was closely associated with the MP differentiation program. H3K4me3 participates in regulating HOXA genes at mild and terminal differentiation periods, while H3K27me3 maintains low-level expression of HOXA genes at phagocytic maintenance periods. Furthermore, the reprogramming of H3K27me3 plays a major role in the up-regulation of KLF4 and FOXO genes during MP differentiation. Importantly, the pharmacological inhibition of H3K4me3 and/or H3K27me3 strikingly promotes the differentiation programs of THP-1 and K562 cells. Together, these findings elucidate mechanisms crucial to the dynamic establishment of epigenetic memory, which is central to the maintenance of the MP differentiation blockade. [ABSTRACT FROM AUTHOR]

Telomeres generally consist of short repeats of minisatellite DNA sequences and are useful in chromosome identification and karyotype analysis. To date, telomeres have not been characterized in the economically important brown seaweed Saccharina japonica, thus its full cytogenetic research and genetic breeding potential has not been realized. Herein, the tentative sequence of telomeres in S. japonica was identified by PCR amplification with primers designed based on the Arabidopsis-type telomere sequence ( TTTAGGG)n, which was chosen out of three possible telomeric repeat DNA sequences typically present in plants and algae. After PCR optimization and cloning, sequence analysis of the amplified products from S. japonica genomic DNA showed that they were composed of repeat units, ( TTTAGGG)n, in which the repeat number ranged from 15 to 63 ( n = 46). This type of repeat sequence was verified by a Southern blot assay with the Arabidopsis-type telomere sequence as a probe. The digestion of S. japonica genomic DNA with the exonuclease Bal31 illustrated that the target sequence corresponding to the Arabidopsis-type telomere sequence was susceptible to Bal31 digestion, suggesting that the repeat sequence was likely located at the outermost ends of the kelp chromosomes. Fluorescence in situ hybridizations with the aforementioned probe provided the initial cytogenetic evidence that the hybridization signals were principally localized at both ends of S. japonica chromosomes. This study indicates that the telomeric repeat of the kelp chromosomes is ( TTTAGGG)n which differs from the previously reported ( TTAGGG)n sequence in Ectocarpus siliculosus through genome sequencing, thereby suggesting distinct telomeres in brown seaweeds. [ABSTRACT FROM AUTHOR]

ABSTRACT Overexposure to manganese (Mn) has been known to disrupt neurotransmitter release in the brain. However, the underlying mechanisms of Mn exposure on neurotransmitter vesicle release are still unclear. The current study investigated whether the protein expression and their interaction of SNARE complex associated proteins were the media between Mn exposure and neurotransmitter vesicle fusion disorders. After the neurons were respectively exposed to Mn (0-200 μM) for 0, 6, 12, 18, 24 h, there were different degrees of cell injury in neurons. According to the results, Mn exposures in subsequent experiments were restricted to concentrations of 100 μM for 0, 6, 12, 18, 24 h. Mn was found to down-regulate the expression of SNAP-25 and up-regulate the expression of VAMP-2 in cultured neurons. Moreover, the interaction of Munc 18 and Syntaxin increased significantly in response to Mn treatment for 18-24h, and the interaction of VAMP-2 and Synaptophysin increased first and then decreased. FM1-43-labeled synaptic vesicles also provided evidence that the treatment with Mn resulted in neurotransmitter vesicle fusion increasing first and then decreasing, which was consistent with the 80 kDa protein levels of SNARE complexes. The findings clearly demonstrated that Mn induced the disorders of neurotransmitter vesicle release via disturbing the protein expression and their interaction of SNARE complex associated proteins. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 705-716, 2017. [ABSTRACT FROM AUTHOR]

A series of novel polymeric cationic surfactants based on low molecular weight chitosan (LWCS) and 3-chloro-2-hydroxypropyl dimethyl dehydroabietyl ammonium chloride (CHPDMDHA), LWCS- g-CHPDMDHA, were obtained by the grafting modification of LWCS with CHPDMDHA as grafting agent. The structure of LWCS- g-CHPDMDHA was confirmed by FT-IR and H NMR, and the degree of quaternizing substitution (DS) of LWCS- g-CHPDMDHA was determined according to the results of elemental analysis. The aggregation behavior and surface activities of LWCS- g-CHPDMDHA in aqueous solution were investigated by transmission electron microscopy (TEM) and determination of surface tension, respectively. The experimental results showed that the DS and molecular weight ( M) of LWCS have significant influence on the critical micelle concentrations (CMC) and the surface tensions at the CMC ( γ). The shape of aggregates changed with the variation of concentration of LWCS- g-CHPDMDHA in aqueous solution. When the LWCS- g-CHPDMDHA was utilized as an emulsifier, the increase of DS of LWCS- g-CHPDMDHA and M of LWCS were favorable for improving the stability of emulsions composed of water and benzene. [ABSTRACT FROM AUTHOR]

A new form of induced transparency enabled by dynamical tunneling coupling of continuous chaos and discrete regular modes in a slightly deformed optical microcavity is demonstrated experimentally. An optical beam is focused on the cavity boundary and tuned on resonance with a high-Q mode, which leads to destructive interference for the excitation of chaotic field and induces a transparency in the transmission. The experimental results are in excellent agreement with a model based on quantum scattering theory. This tunneling-induced transparency is accompanied by extremely steep normal dispersion, and holds great potential in slow light and enhanced nonlinear interactions. [ABSTRACT FROM AUTHOR]

Free-radical initiated grafting of maleic anhydride (MAH)/polyfunctional acrylate (PFA) multimonomer system onto polypropylene (PP) via reactive extrusion was studied. The effects of PFA and initiator concentration on the grafting reaction were investigated. It was shown that PFA as a comonomer could greatly enhance MAH grafting degree, which increased monotonically as the molar ratio of PFA to MAH increased. The rheology test demonstrated that the viscosity of grafted PP was also promoted as more PFA was used. The formation of branched structure during the grafting process was proved by oscillatory shear rheological analysis. The mechanism of grafting in the presence of PFA was discussed, suggesting PFA had higher reactivity with PP macroradicals than MAH and therefore forming stabilized macroradicals, thus resulting in depression of β-scission and favoring the formation of branched structure. Higher initiator concentration gave higher MAH grafting degree but more severe degradation. The mechanical properties of the grafted PP were comparable with those of unmodified PP. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

Histone lysine acetylation, normally associated with euchromatin and active genes, is regulated by different families of histone acetyltransferases (HATs). A single Plasmodium falciparum MYST (PfMYST) HAT was expressed as a long and a short version in intraerythrocytic stages. Whereas the recombinant PfMYST expressed in prokaryotes and insect cells did not show HAT activity, recombinant PfMYST purified from the parasites exhibited a predilection to acetylate histone H4 in vitro at K5, K8, K12 and K16. Tagging PfMYST with the green fluorescent protein at the C-terminus showed that PfMYST protein was localized in both the nucleus and cytoplasm. Consistent with the importance of H4 acetylation in var gene expression, PfMYST was recruited to the active var promoter. Attempts to disrupt PfMYST were not successful, suggesting that PfMYST is essential for asexual intraerythrocytic growth. However, overexpression of the long, active or a truncated, non-active version of PfMYST by stable integration of the expression cassette in the parasite genome resulted in changes of H4 acetylation and cell cycle progression. Furthermore, parasites with PfMYST overexpression showed changes in sensitivity to DNA-damaging agents. Collectively, this study showed that PfMYST plays important roles in cellular processes such as gene activation, cell cycle control and DNA repair. [ABSTRACT FROM AUTHOR]

Three new triterpenoids, turrapubesols A–C (1–3), and one new sesquiterpenoid, 1α,4α-dihydroxyeudesman-11-ene (4), along with 12 known terpenoids were isolated from Turraea pubescens. The structures of the terpenoids were established on the basis of extensive spectroscopic analyses and by a chemical transformation. The previous assignment of the NMR data for guaidiol (5) was corrected. Some of the triterpenoids exhibited cytotoxicity against the P-388 cell line. [ABSTRACT FROM AUTHOR]

Seventeen Daphniphyllum alkaloids, including two new pentacyclic alkaloids, yuzuric acid (1) and daphnezomic acid (2), and 15 known ones, were isolated from the fruits of Daphniphyllum oldhamii. The structures and configuration of the two new alkaloids were determined on the basis of spectroscopic methods, especially 2D NMR techniques. [ABSTRACT FROM AUTHOR]

Three new alkaloids, N-hydroxypaxdaphnine B (1), 21-O-acetylpaxdaphnine B (2), and methyl 17-hydroxyhomodaphniphyllate (3), were isolated from the fresh fruits of Daphniphyllum macropodum, together with six known alkaloids. Their structures were established on the basis of extensive spectroscopic and mass-spectrometric analyses in combination with chemical transformations. [ABSTRACT FROM AUTHOR]

Two new lignan glycosides, lanicepsides A and B (1 and 2), along with the eight known compounds 3–6, epipinoresinol, syringin, ethyl caffeate, and 5,6,7-trihydroxy-4′-methoxyflavone, including sesquiterpene lactones, lignans, and a flavone, were isolated from the ethanol extract of Saussurea laniceps. Their structures were determined by spectroscopic methods especially 1D- and 2D-NMR techniques. [ABSTRACT FROM AUTHOR]

Three new natural products, the taraxastane-type triterpenoid 1, the azafluorene-based constituent 2-hydroxyonychine (2), and the diterpenoid nemoralisin (3) were isolated from the EtOH extract of Polyalthia nemoralis, along with five known compounds. The structures of the new compounds were established by in-depth spectroscopic and mass-spectrometric analyses, as well as by chemical transformation. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented regarding the premature infants' stability after being transported from tertiary to secondary level centres in Melbourne, Australia.

In the cation of the title compound, C15H17N3O+·PF6−, the dihedral angle between the mean planes of the quinoline and imidazole groups is 78.02 (7)°. In the crystal structure, π–π stacking interactions, with a ring centroid separation of 3.752 (2) Å, link the molecules into centrosymmetric dimers. In addition, weak intermolecular C—H...F and C—H...O interactions help to stabilize the crystal structure. The F atoms of the anion are disordered over two sites in a ratio of approximately 0.86:0.14. [ABSTRACT FROM AUTHOR]