Revision of the planthopper genus Nycheuma Fennah (Hemiptera,Fulgoromorpha, Delphacidae)

Chinese species in the genus Nycheuma Fennah, 1964a (Hemiptera: Fulgoromorpha: Delphacidae: Delphacinae: Delphacini) are revised to include three species: Nycheuma cognatum (Muir, 1917), Nycheuma dimorpha (Matsumura, 1910) and Nycheuma nilotica Linnavuori, 1973. Nycheuma coctum Yang, 1989 is placed in synonymy with Nycheuma nilotica Linnavuori, 1973. Nycheuma dimorpha (Matsumura, 1910) is newly recorded from China. The generic characteristics are redefined. The main morphological characters, male genitalia of 3 species are described or redescribed and illustrated. A key to Chinese species in the genus is provided.     

IFT52 plays an essential role in sensory cilia formation and neuronal sensory function in Drosophila

Cilia are microtubule-based, hair-like organelles involved in sensory function or motility, playing critical roles in many physiological processes such as reproduction, organ development, and sensory perception. In insects, cilia are restricted to certain sensory neurons and sperms, being important for chemical and mechanical sensing, and fertility. Although great progress has been made regarding the mechanism of cilia assembly, the formation of insect cilia remains poorly understand, even in the insect model organism Drosophila. Intraflagellar transport (IFT) is a cilia-specific complex that traffics protein cargos bidirectionally along the ciliary axoneme and is essential for most cilia. Here we investigated the role of IFT52, a core component of IFT-B, in cilia/flagellar formation in Drosophila. We show that Drosophila IFT52 is distributed along the sensory neuronal cilia, and is essential for sensory cilia formation. Deletion of Ift52 results in severe defects in cilia-related sensory behaviors. It should be noted that IFT52 is not detected in spermatocyte cilia or sperm flagella of Drosophila. Accordingly, ift52 mutants can produce sperms with normal motility, supporting a dispensable role of IFT in Drosophila sperm flagella formation. Altogether, IFT52 is a conserved protein essential for sensory cilia formation and sensory neuronal function in insects.     

Anti-cancer activities of tea epigallocatechin-3-gallate in breast cancer patients under radiotherapy

The purpose of this study was to test the hypothesis that administration of epigallocatechin-3-gallate (EGCG), a polyphenol present in abundance in widely consumed tea, inhibits cell proliferation, invasion, and angiogenesis in breast cancer patients. EGCG in 400 mg capsules was orally administered three times daily to breast cancer patients undergoing treatment with radiotherapy. Parameters related to cell proliferation, invasion, and angiogenesis were analyzed while blood samples were collected at different time points to determine efficacy of the EGCG treatment. Compared to patients who received radiotherapy alone, those given radiotherapy plus EGCG for an extended time period (two to eight weeks) showed significantly lower serum levels of vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), and reduced activation of metalloproteinase-9 and metalloproteinase-2 (MMP9/MMP2). Addition of sera obtained from patients treated with combination of radiotherapy and EGCG feeding for 2-8 weeks to in vitro cultures of highly-metastatic human MDA-MB-231 breast cancer cells resulted in the following significant changes: (1) suppression of cell proliferation and invasion; (2) arrest of cell cycles at the G0/G1 phase; (3) reduction of activation of MMP9/MMP2, expressions of Bcl-2/Bax, c-Met receptor, NF-κB, and the phosphorylation of Akt. MDA-MB-231 cells exposed to 5-10 μM EGCG also showed significant augmentation of the apoptosis inducing effects of γ-radiation, concomitant with reduced NF-κB protein level and AKT phosphorylation. These results provide hitherto unreported evidence that EGCG potentiated efficacy of radiotherapy in breast cancer patients, and raise the possibility that this tea polyphenol has potential to be a therapeutic adjuvant against human metastatic breast cancer.     

Synthesis and Antiproliferative Activities of Novel Substituted 5‐Anilino‐α‐Glucofuranose Derivatives

In order to find novel antitumor candidate agents with high efficiency and low toxicity, 14 novel substituted 5‐anilino‐α‐glucofuranose derivatives have been designed, synthesized and evaluated for antiproliferative activities in vitro. Their structures were characterized by NMR (¹H and ¹³C) and HR‐MS, and configuration (R/S) at C(5) was identified by two‐dimensional ¹H,¹H‐NOESY‐NMR spectrum. Their antiproliferative activities against human tumor cells were investigated by MTT assay. The results demonstrated that most of the synthesized compounds had antiproliferative effects comparable to the reference drugs gefitinib and lapatinib. In particular, (5R)‐5‐O‐(3‐chloro‐4‐{[5‐(4‐fluorophenyl)thiophen‐2‐yl]methyl}anilino)‐5‐deoxy‐1,2‐O‐(1‐methylethylidene)‐α‐glucofuranose ( 9da ) showed the most potent antiproliferative effects against SW480, A431 and A549 cells, with IC₅₀ values of 8.57, 5.15 and 15.24 μm , respectively. This work suggested 5‐anilino‐α‐glucofuranose as an antitumor core structure that may open a new way to develop more potent anti‐cancer agents.     

Mechanisms of Metabonomic for a Gateway Drug: Nicotine Priming Enhances Behavioral Response to Cocaine with Modification in Energy Metabolism and Neurotransmitter Level

Nicotine, one of the most commonly used drugs, has become a major concern because tobacco serves as a gateway drug and is linked to illicit drug abuse, such as cocaine and marijuana. However, previous studies mainly focused on certain genes or neurotransmitters which have already been known to participate in drug addiction, lacking endogenous metabolic profiling in a global view. To further explore the mechanism by which nicotine modifies the response to cocaine, we developed two conditioned place preference (CPP) models in mice. In threshold dose model, mice were pretreated with nicotine, followed by cocaine treatment at the dose of 2 mg/kg, a threshold dose of cocaine to induce CPP in mice. In high-dose model, mice were only treated with 20 mg/kg cocaine, which induced a significant CPP. ¹H nuclear magnetic resonance based on metabonomics was used to investigate metabolic profiles of the nucleus accumbens (NAc) and striatum. We found that nicotine pretreatment dramatically increased CPP induced by 2 mg/kg cocaine, which was similar to 20 mg/kg cocaine-induced CPP. Interestingly, metabolic profiles showed considerable overlap between these two models. These overlapped metabolites mainly included neurotransmitters as well as the molecules participating in energy homeostasis and cellular metabolism. Our results show that the reinforcing effect of nicotine on behavioral response to cocaine may attribute to the modification of some specific metabolites in NAc and striatum, thus creating a favorable metabolic environment for enhancing conditioned rewarding effect of cocaine. Our findings provide an insight into the effect of cigarette smoking on cocaine dependence and the underlying mechanism.     

酸雨背景下缙云山典型林分凋落物量和营养元素含量及其释放特征

选取缙云山针阔混交林、常绿阔叶林、楠竹林和灌木林作为研究对象,对4种林分的凋落物储量和营养元素释放量等进行观测,并应用室内模拟酸雨实验对4种林分凋落物进行淋溶模拟。结果表明:缙云山各林分现存凋落物厚度为1.4～4.5 cm,具有明显的分层结构;林分未分解U层、半分解S层和分解D层现存凋落物量分别为1.97～8.59、2.84～10.18和3.58～17.43 t·hm-2,林分年凋落物量为2.17～9.86 t·hm-2·a-1,凋落物总储量为14.21～32.42 t·hm-2,凋落物分解常数为0.15～0.31,林下凋落物分解95%时所需时间针阔混交林和楠竹林均在10年以上,凋落物分解速率比较缓慢;林下凋落物层营养元素含量以Ca、N为主,Fe、K、Mg次之;凋落物总的营养元素释放率表现为常绿阔叶林(0.80)>灌木林(0.72)>针阔混交林(0.50)>楠竹林(-0.17);与叶片相比,凋落物中N、K、Mn 3种营养元素含量明显降低;为探明酸雨影响营养元素循环的作用机理,对模拟酸雨的离子含量与凋落物淋滤液盐基离子含量进行了分析,其相关性大小表现为楠竹林(相关系数0.895)>针阔混交林(0.826)>灌木(0.700)>常绿阔叶林(0.699),楠竹林凋落物营养元素的淋滤受酸雨影响最大,常绿阔叶林受其影响最弱;推测在这一过程中以凋落物的吸附作用为主。     

Genome-wide identification and phylogenetic analysis of Family-1 UDP glycosyltransferases in maize (Zea mays)

Family-1 UDP glycosyltransferases (UGTs) from plants transfer sugar moieties from activated sugar donors to a wide range of small molecules, and control many metabolic processes during plant growth and development. Here, we report a genome-wide analysis of maize that identified 147 Family-1 glycosyltransferases based on their conserved PSPG motifs. Phylogenetic analysis of these genes with 18 Arabidopsis UGTs and two rice UGTs clustered them into 17 groups (A–Q). The patterns of intron gain/loss events, as well as their positions within UGTs from the same group, further aided elucidation of their divergence and evolutionary relationships between UGTs. Expression analysis of the maize UGT genes using both online microarray data and quantitative real-time PCR verification indicates that UGT genes are widely expressed in various tissues and likely play important roles in plant growth and development. Our study provides useful information on the Family-1 UGTs in maize, and will facilitate their further characterization to better understand their functions.     

Theoretical study of the triangular bonding complex formed by carbon tetrabromide, a halide, and a solvent molecule in the gas phase

MP2(full)/aug-cc-pVDZ(-PP) computations predict that new triangular bonding complexes (where X^? is a halide and H–C refers to a protic solvent molecule) consist of one halogen bond and two hydrogen bonds in the gas phase. Carbon tetrabromide acts as the donor in the halogen bond, while it acts as an acceptor in the hydrogen bond. The halide (which commonly acts as an acceptor) can interact with both carbon tetrabromide and solvent molecule (CH₃CN, CH₂Cl₂, CHCl₃) to form a halogen bond and a hydrogen bond, respectively. The strength of the halogen bond obeys the order CBr₄???Cl^? > CBr₄???Br^? > CBr₄???I^?. For the hydrogen bonds formed between various halides and the same solvent molecule, the strength of the hydrogen bond obeys the order C-H???Cl^? > C-H???Br^? > C-H???I^?. For the hydrogen bonds formed between the same halide and various solvent molecules, the interaction strength is proportional to the acidity of the hydrogen in the solvent molecule. The diminutive effect is present between the hydrogen bonds and the halogen bond in chlorine and bromine triangular bonding complexes. Complexes containing iodide ion show weak cooperative effects.

Baicalein Inhibits Staphylococcus aureus Biofilm Formation and the Quorum Sensing System In Vitro

Biofilm formed by Staphylococcus aureus significantly enhances antibiotic resistance by inhibiting the penetration of antibiotics, resulting in an increasingly serious situation. This study aimed to assess whether baicalein can prevent Staphylococcus aureus biofilm formation and whether it may have synergistic bactericidal effects with antibiotics in vitro. To do this, we used a clinically isolated strain of Staphylococcus aureus 17546 (t037) for biofilm formation. Virulence factors were detected following treatment with baicalein, and the molecular mechanism of its antibiofilm activity was studied. Plate counting, crystal violet staining, and fluorescence microscopy revealed that 32 μg/mL and 64 μg/mL baicalein clearly inhibited 3- and 7-day biofilm formation in vitro. Moreover, colony forming unit count, confocal laser scanning microscopy, and scanning electron microscopy showed that vancomycin (VCM) and baicalein generally enhanced destruction of biofilms, while VCM alone did not. Western blotting and real-time quantitative polymerase chain reaction analyses (RTQ-PCR) confirmed that baicalein treatment reduced staphylococcal enterotoxin A (SEA) and α-hemolysin (hla) levels. Most strikingly, real-time qualitative polymerase chain reaction data demonstrated that 32 μg/mL and 64 μg/mL baicalein downregulated the quorum-sensing system regulators agrA, RNAIII, and sarA, and gene expression of ica, but 16 μg/mL baicalein had no effect. In summary, baicalein inhibited Staphylococcus aureus biofilm formation, destroyed biofilms, increased the permeability of vancomycin, reduced the production of staphylococcal enterotoxin A and α-hemolysin, and inhibited the quorum sensing system. These results support baicalein as a novel drug candidate and an effective treatment strategy for Staphylococcus aureus biofilm-associated infections.