bluuebunny/crossref_metadata_2025 huggingface dataset:
1,4,7,10‐Tetraisoalkyltetracenes: Tuning of Solid‐State Optical Properties and Fluorescence Quantum Yields by Peripheral Modulation (Eur. J. Org. Chem. 16/2010)
Authors: Kitamura Chitoshi , Tsukuda Hideki , Yoneda Akio , Kawase Takeshi , Kobayashi Takashi , Naito Hiroyoshi
Published: May 2010

The cover picture shows 1,4,7,10‐tetraisoalkyltetracenes in the solid state under UV light irradiation and under natural light. The photophysical properties exhibit crystallochromy ranging from yellow to red and different fluorescence quantum yields depending on the length of the alkyl side chain. The isopropyl derivative achieved the highest quantum yield ever reported among tetracenes. Details are discussed in the article by C. Kitamura et al. on p. 3033 ff. The background of the cover picture is a night view of Himeji Castle, which is well known for its beauty and supposed resemblance to an egret (it was accorded UNESCO World Heritage Site status in 1993). The authors would like to thank Hiroko Kitamura for her help in designing the cover picture.
Biodegradable protein‐based films from plant resources: A review
Authors: Zhang Hongkang , Mittal Gauri
Published: May 2010

This review provides an overview of studies on the film‐forming properties of soy protein, wheat gluten and corn zein. Biodegradable films from these proteins have been investigated extensively. Casting is the most often used film‐forming method. Glycerol is added as plasticizer in many studies. The proteins are normally dissolved or dispersed in suitable solvents with plasticizers. The resulting solutions or dispersions form free standing films on a plate by casting the mixture and subsequent drying. Posttreatments such as coating, heating, and radiation are also employed to improve film properties. These protein films in general are water sensitive and lack mechanical strength but are good oxygen barriers. Further studies to improve the properties of the films for food packaging materials are also discussed. © 2010 American Institute of Chemical Engineers Environ Prog, 2010
Seismic vulnerability evaluation of RC moment frame buildings in moderate seismic zones
Authors: El Howary H. A. , Mehanny S. S. F.
Published: May 2010

A multi‐level seismic vulnerability assessment of reinforced concrete moment frame buildings located in moderate seismic zones (0.25g) is performed on a set of ductile versions of low‐ to mid‐rise two‐dimensional moment frames. The study is illustrated through application to comparative trial designs of two (4‐ and 8‐story) buildings adopting both space‐ and perimeter‐framed approaches. All frames are dimensioned as per the emerging version of the seismic design code in Egypt. These new seismic provisions are in line with current European norms for seismic design of buildings. Code‐compliant designs (CCD), as well as a proposed modified code design relaxing design drift demands for the investigated buildings, are examined to test their effectiveness and reliability. Applying nonlinear inelastic incremental dynamic analyses, fragility curves (FC) for the frames are developed corresponding to various code‐specified performance levels. Code preset lower and upper bounds on design acceleration and drift, respectively, are also addressed along with their implications, if imposed, on the frames seismic performance and vulnerability. Annual spectral acceleration hazard curves for the case study frames are also generated. Estimates for mean annual frequency (MAF) of exceeding various performance levels are then computed through an integration process of the data resulting from the FC with the site hazard curves. The study demonstrates that the proposed design procedure relaxing design drift demands delivers more economic building designs relative to CCDs, yet without risking the global safety of the structure. The relaxed design technique suggested herein, even though scoring higher, as expected by intuition, MAF of exceeding various code‐limiting performance levels expressed in terms of interstory drift ratios, still guarantees a reasonably acceptable actual margin against violating code limits for such levels. Copyright © 2010 John Wiley & Sons, Ltd.
Empowered or overpowered? Service use, needs, wants and demands in elderly patients with cognitive impairments
Authors: Wolfs Claire A. G. , de Vugt Marjolein E. , Verkaaik Mike , Verkade Paul‐Jeroen , Verhey Frans R. J.
Published: May 2010

Background

Examination of clinical practice reveals that current treatment options are often not sufficiently utilized by patients suffering from dementia or mild cognitive impairment.

Objective

This study aimed to investigate to what extent and in what way these patients utilize the available treatment options, as well as to identify factors and reasons that play a role in the non‐utilization of these options.

Methods

Semi‐structured interviews by telephone were held with the patients' caregivers.

Results

Counseling, medication, activities and home care were the options that were most frequently utilized by the 252 patients and caregivers who were included in the study. Group guidance and admissions were the main treatment categories that had not been utilized (although they were proposed). The most important reasons given were refusal by the patient and the fact that help was not necessary yet according to the caregiver. Burden of care and cognition were the most important factors in predicting which of the treatment options were not utilized.

Conclusions

Most patients and caregivers are not aware of the treatment options available to them. Awareness of these options is necessary to avoid situations in which patients and caregivers find themselves with their backs against the wall and the need for care support has become an acute necessity. Health care professionals should play an important role with regard to this empowerment. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis and Chemical Properties of Diacetylenes with Pyridinium and 4,4′‐Bipyridinium Groups
Authors: Yamaguchi Isao , Higashi Hideo , Kimura Shunsuke , Sato Moriyuki
Published: May 2010

Diacetylenes (DAs) having a dipolar D‐π‐A structure (D=donor: amino group; π=π‐conjugation core; A=acceptor: pyridinium (Py) and bipyridinium (BPy) groups), i.e., 4 (APBPyDA) and 5 (APPyPyDA), or an A‐π‐A structure, i.e., 7 (DBPyDA) and 8 (PyDA(Cl)), were obtained by 1 : 1 and 1 : 2 reactions of 4,4′‐(buta‐1,3‐diyne‐1,4‐diyl)bis[benzenamine] (APDA; 3) with 1‐(2,4‐dinitrophenyl)‐1′‐hexyl‐4,4′‐bipyridinium bromide chloride (1 : 1 : 1) (1), 1‐(2,4‐dinitrophenyl)‐4‐(pyridin‐4‐yl)pyridinium chloride (2), or 1‐(2,4‐dinitrophenyl)pyridinium chloride (6) (Schemes 1 and 2). The anion‐exchange reactions of 8 with NaI and Li(TCNQ) (TCNQ−=2,2′‐(cyclohexa‐2,5‐diene‐1,4‐diylidene)bis[propanedinitrile] radical ion (1−)) yielded the corresponding I− and TCNQ− salts 9 (PyDA(I)) and 10 (PyDA(TCNQ)). Compounds 10 and 4 exhibited a UV/VIS absorption due to a charge transfer between the TCNQ− and the pyridinium groups and a strong solute–solvent interaction of a dipolar solute molecule in the polar environment, respectively. Compounds 8–10 exhibited photoluminescence in solution, whereas 4 and 7 did not because of the presence of the 4,4′‐bipyridinium quenching groups. Differential‐scanning‐calorimetry (DSC) measurements suggested that the DAs obtained in this study can be converted into poly(diacetylenes) by thermal polymerization.
First Total Synthesis of Mappain with a Prenylated and Geranylated Stilbene
Authors: Chakrapani Lakkoju , Jung Eun Mi , Lee Yong Rok
Published: May 2010

The first total synthesis of naturally occurring mappain has been achieved by a convergent sequence. The key strategy involved in the synthesis of mappain was a (E)‐stilbene formation by Horner–Wadsworth–Emmons reaction of the corresponding prenylated benzaldehyde with a geranylated benzyl phosphonate.
Formation and Decomposition of Diazo Ethers under Acidic Conditions. Effects of Ethanol Concentration, Acidity, and Temperature on the Ethanolysis of 4‐Methylbenzenediazonium Ions
Authors: Fernández‐Alonso Alejandra , Bravo‐Díaz Carlos
Published: May 2010

We investigated the effects of solvent composition, acidity, and temperature on the dediazoniation of 4‐methylbenzenediazonium (4MBD) ions in EtOH/H2O mixtures by employing a combination of spectrometric and chromatographic techniques. First‐order behavior is found in all solvent composition ranges. HPLC Analyses of the reaction mixtures indicate that three main dediazoniation products are formed depending on the particular experimental conditions. These are 4‐cresol (ArOH), 4‐phenetole (ArOEt), and toluene (ArH). At acidities (defined as −log [HCl])<2, the main dediazoniation products are the substitution products ArOH and ArOEt but upon decreasing the acidity, the reduction product ArH becomes predominant at the expense of ArOH and ArOEt, indicating that a turnover in the reaction mechanism takes place under acidic conditions. At any given EtOH content, the plot of kobs values against acidity is S‐shaped, the inflexion point depending upon the EtOH concentration and the temperature. Similar S‐shaped variations are found when plotting the dediazoniation–product distribution against the acidity. The acid dependence of the switch between the homolytic and heterolytic mechanisms suggests that the homolytic dediazoniation proceeds via transient diazo ethers, and this complex kinetic behavior can be rationalized by assuming two competitive mechanisms: i) the spontaneous heterolytic dediazoniation of 4MBD, and ii) an O‐coupling mechanism in which the EtOH molecules capture ArN$\rm{{_{2}^{+}}}$ to yield a highly unstable (Z)‐adduct which undergoes homolytic fragmentation initiating a radical process (Scheme). Analyses of the effects of temperature on the equilibrium constant for the formation of the diazo ether and on the rate of splitting of the diazo ether allowed the estimation of relevant thermodynamic parameters for the formation of diazo ethers derived from methylbenzenediazonium ions under acidic conditions.
Seven Novel Linear Polyketides from Xylaria sp. NCY2
Authors: Hu Zhi‐Yu , Li Yao‐Yao , Lu Chun‐Hua , Lin Ting , Hu Ping , Shen Yue‐Mao
Published: May 2010

Seven novel polyketides, namely, 1‐(xylarenone A)xylariate A (1), xylarioic acid B (2), xylariolide A (3), xylariolide B (4), xylariolide C (5), methyl xylariate C (6), and xylariolide D (7), together with the known one taiwapyrone (8), were isolated from the endophytic fungal strain Xylaria sp. NCY2 of Torreya jackii Chun. Their structures were elucidated by spectroscopic analyses, including 1D‐ and 2D‐NMR experiments, and on the basis of HR‐Q‐TOF mass spectrometry. Antitumor and antibacterial assays of compounds 1–8 were carried out, which show moderate activities.
Synthesis of Novel Polycyclic Indole‐Annulated Thiopyranocoumarin Derivatives via Domino Knoevenagel–Hetero‐Diels–Alder Reaction in Aqueous Media
Authors: Moghaddam Firouz Matloubi , Kiamehr Mostafa , Taheri Salman , Mirjafary Zohreh
Published: May 2010

An efficient synthesis of polycyclic indole derivatives is achieved via domino Knoevenagel–hetero‐Diels–Alder reaction of O‐acrylated salicylaldehyde derivatives with dihydroindole‐2‐thiones in H2O as solvent. The products are formed in good‐to‐excellent yields with high regio‐ and stereoselectivity.
An Efficient N‐Arylation of Heterocycles with Aryl‐, Heteroaryl‐, and Vinylboronic Acids Catalyzed by Copper Fluorapatite
Authors: Kantam Mannepalli Lakshmi , Venkanna Gopaladasu Tirupati , Kumar Kota Balaji Shiva , Subrahmanyam Vura Bala
Published: May 2010

N‐Arylation of N‐containing heterocycles, such as pyrazoles, imidazoles, and benzimidazoles with aryl‐, heteroaryl‐, and vinylboronic acids was efficiently carried out by copper fluorapatite (CuFAP) catalyst in MeOH at room temperature under base‐free conditions. The N‐arylated heterocycles were isolated in good‐to‐excellent yields.
Study of Lysozyme Glycation Reaction by Mass Spectrometry and NMR Spectroscopy
Authors: Maekawa Yukiko , Sugiura Makiko , Takeuchi Atsuko , Tomoo Koji , Ishida Toshimasa , Kamigauchi Miyoko
Published: May 2010

The Advanced Glycation End Products (AGEs) are the causative substances of lifestyle‐habit illness. To elucidate the glycation mechanism of the protein, the reaction of lysozyme with D‐glucose was analyzed by the fluorescence, TOF‐MS, and 13C‐NMR spectroscopy under the physiological condition. The fluorescence intensity of lysozyme in the glycation solution increased proportionally with a reaction time of ten weeks. The MALDI‐TOF‐MS spectra of the reaction solution after two weeks showed a peak at m/z 15066, which indicated the presence of a larger molecule than the native lysozyme (m/z 14331), and new peaks at m/z 30105 (dimer) and 45000 (trimer) were also observed. The spectral analysis supported the assumption of a continuous glycation reaction of D‐glucose with lysozyme and a 30% transformation of lysozyme to the dimeric form during ten weeks. The 13C‐NMR spectra of lysozyme showed six [13C]‐labeled signals by the glycation reaction with [13C]‐glucose after two weeks of reaction. The combined analysis of TOF‐MS and 13C‐NMR spectra uncovered that first products of the glycation reaction of lysozyme with D‐glucose can be observed already three hours after starting the reaction and that nine D‐glucose units are attached during ten weeks at 37°.
Tri‐ and Tetrasubstituted N‐Phthalimidoaziridines in 1,3‐Dipolar Cycloaddition Reactions
Authors: Ushkov Alexander V. , Kuznetsov Mikhail A. , Linden Anthony , Heimgartner Heinz
Published: May 2010

The thermal reactions of the 2,2,3‐trisubstituted N‐phthalimidoaziridine 1a with dimethyl acetylenedicarboxylate (DMAD), thioketones 4a–4d, and dimethyl azodicarboxylate (5) proceed even at room temperature leading to the five‐membered cycloadducts 2a, 6–8, and 12, respectively, with retention of the spatial arrangement of the aziridine substituents, in contrast to the expectation based on the conservation of orbital symmetry in concerted reactions. The analogous reactions of the tetrasubstituted phthalimidoaziridine 1b with thioketones at 40° lead to the 1,3‐thiazolidine derivatives 10 and 11 as mixtures of diastereoisomers. These unexpected results may be explained by either the isomerization of the intermediate azomethine ylides or a non‐concerted stepwise cycloaddition reaction of these ylides with the dipolarophiles. The structures of some adducts have been determined by X‐ray crystallography.
Insulin-like growth factor 2 (IGF-2) potentiates BMP-9-induced osteogenic differentiation and bone formation
Authors: Chen Liang , Jiang Wei , Huang Jiayi , He Bai-Cheng , Zuo Guo-Wei , Zhang Wenli , Luo Qing , Shi Qiong , Zhang Bing-Qiang , Wagner Eric R , Luo Jinyong , Tang Min , Wietholt Christian , Luo Xiaoji , Bi Yang , Su Yuxi , Liu Bo , Kim Stephanie H , He Connie J , Hu Yawen , Shen Jikun , Rastegar Farbod , Huang Enyi , Gao Yanhong , Gao Jian-Li , Zhou Jian-Zhong , Reid Russell R , Luu Hue H , Haydon Rex C , He Tong-Chuan , Deng Zhong-Liang
Published: May 2010

Efficient osteogenic differentiation and bone formation from mesenchymal stem cells (MSCs) should have clinical applications in treating nonunion fracture healing. MSCs are adherent bone marrow stromal cells that can self-renew and differentiate into osteogenic, chondrogenic, adipogenic, and myogenic lineages. We have identified bone morphogenetic protein 9 (BMP-9) as one of the most osteogenic BMPs. Here we investigate the effect of insulin-like growth factor 2 (IGF-2) on BMP-9-induced bone formation. We have found that endogenous IGF-2 expression is low in MSCs. Expression of IGF-2 can potentiate BMP-9-induced early osteogenic marker alkaline phosphatase (ALP) activity and the expression of later markers. IGF-2 has been shown to augment BMP-9-induced ectopic bone formation in the stem cell implantation assay. In perinatal limb explant culture assay, IGF-2 enhances BMP-9-induced endochondral ossification, whereas IGF-2 itself can promote the expansion of the hypertropic chondrocyte zone of the cultured limb explants. Expression of the IGF antagonists IGFBP3 and IGFBP4 leads to inhibition of the IGF-2 effect on BMP-9-induced ALP activity and matrix mineralization. Mechanistically, IGF-2 is further shown to enhance the BMP-9-induced BMPR-Smad reporter activity and Smad1/5/8 nuclear translocation. PI3-kinase (PI3K) inhibitor LY294002 abolishes the IGF-2 potentiation effect on BMP-9-mediated osteogenic signaling and can directly inhibit BMP-9 activity. These results demonstrate that BMP-9 crosstalks with IGF-2 through PI3K/AKT signaling pathway during osteogenic differentiation of MSCs. Taken together, our findings suggest that a combination of BMP-9 and IGF-2 may be explored as an effective bone-regeneration agent to treat large segmental bony defects, nonunion fracture, and/or osteoporotic fracture. © 2010 American Society for Bone and Mineral Research.
Dietary-induced serum phenolic acids promote bone growth via p38 MAPK/β-catenin canonical Wnt signaling
Authors: Chen Jin-Ran , Lazarenko Oxana P , Wu Xianli , Kang Jie , Blackburn Michael L , Shankar Kartik , Badger Thomas M , Ronis Martin JJ
Published: May 2010

Diet and nutritional status are critical factors that influences bone development. In this report we demonstrate that a mixture of phenolic acids found in the serum of young rats fed blueberries (BB) significantly stimulated osteoblast differentiation, resulting in significantly increased bone mass. Greater bone formation in BB diet–fed animals was associated with increases in osteoblast progenitors and osteoblast differentiation and reduced osteoclastogenesis. Blockade of p38 phosphorylation eliminated effects of BB on activation of Wnt signaling in preosteoblasts. Knocking down β-catenin expression also blocked the ability of serum from BB diet–fed rats to stimulate osteoblast differentiation in vitro. Based on our in vivo and in vitro data, we propose that the underlying mechanisms of these powerful bone-promoting effects occur through β-catenin activation and the nuclear accumulation and transactivation of TCF/LEF gene transcription in bone and in osteoblasts. These results indicate stimulation of molecular events leading to osteoblast differentiation triggered by P38 MAP kinase (MAPK)/β-catenin canonical Wnt signaling results in significant increases in bone growth in young rats consuming BB-supplemented diets. Liquid chromatography/mass spectrometry (LC/MS) characterization of the serum after BB feeding revealed a mixture of simple phenolic acids that may provide a basis for developing a new treatment to increase peak bone mass and delay degenerative bone disorders such as osteoporosis. © 2010 American Society for Bone and Mineral Research.
Melatonin protects against taurolithocholic‐induced oxidative stress in rat liver
Authors: Fuentes‐Broto Lorena , Miana‐Mena Francisco J. , Piedrafita Eduardo , Berzosa César , Martínez‐Ballarín Enrique , García‐Gil Francisco A. , Reiter Russel J. , García Joaquín J.
Published: May 2010

Cholestasis, encountered in a variety of clinical disorders, is characterized by intracellular accumulation of toxic bile acids in the liver. Furthermore, oxidative stress plays an important role in the pathogenesis of bile acids. Taurolithocholic acid (TLC) was revealed in previous studies as the most pro‐oxidative bile acid. Melatonin, a well‐known antioxidant, is a safe and widely used therapeutic agent. Herein, we investigated the hepatoprotective role of melatonin on lipid and protein oxidation induced by TLC alone and in combination with FeCl3 and ascorbic acid in rat liver homogenates and hepatic membranes. The lipid peroxidation products, malondialdehyde and 4‐hydroxyalkenals (MDA + 4‐HDA), and carbonyl levels were quantified as indices of oxidative damage to hepatic lipids and proteins, respectively. In the current study, the rise in MDA + 4‐HDA levels induced by TLC was inhibited by melatonin in a concentration‐dependent manner in both liver homogenates and in hepatic membranes. Melatonin also had protective effects against structural damage to proteins induced by TLC in membranes. These results suggest that the indoleamine melatonin may potentially act as a protective agent in the therapy of those diseases that involve bile acid toxicity. J. Cell. Biochem. 110: 1219–1225, 2010. Published 2010 Wiley‐Liss, Inc.
The transcriptional programme of contact‐inhibition
Authors: Küppers Monika , Ittrich Carina , Faust Dagmar , Dietrich Cornelia
Published: May 2010

Proliferation of non‐transformed cells is regulated by cell–cell contacts, which are referred to as contact‐inhibition. Vice versa, transformed cells are characterised by a loss of contact‐inhibition. Despite its generally accepted importance for cell‐cycle control, little is known about the intracellular signalling pathways involved in contact‐inhibition. Unravelling the molecular mechanisms of contact‐inhibition and its loss during tumourigenesis will be an important step towards the identification of novel target genes in tumour diagnosis and treatment. To better understand the underlying molecular mechanisms we identified the transcriptional programme of contact‐inhibition in NIH3T3 fibroblast using high‐density microarrays. Setting the cut off: ≥1.5‐fold, P ≤ 0.05, 853 genes and 73 cDNA sequences were differentially expressed in confluent compared to exponentially growing cultures. Importing these data into GenMAPP software revealed a comprehensive list of cell‐cycle regulatory genes mediating G0/G1 arrest, which was confirmed by RT‐PCR and Western blot. In a narrow analysis (cut off: ≥2‐fold, P ≤ 0.002), we found 110 transcripts to be differentially expressed representing 107 genes and 3 cDNA sequences involved, for example, in proliferation, signal transduction, transcriptional regulation, cell adhesion and communication. Interestingly, the majority of genes was upregulated indicating that contact‐inhibition is not a passive state, but actively induced. Furthermore, we confirmed differential expression of eight genes by semi‐quantitative RT‐PCR and identified the potential tumour suppressor transforming growth factor‐β (TGF‐β)‐1‐induced clone 22 (TSC‐22; tgfb1i4) as a novel protein to be induced in contact‐inhibited cells. J. Cell. Biochem. 110: 1234–1243, 2010. Published 2010 Wiley‐Liss, Inc.
p120‐catenin is a binding partner and substrate for Group B Pak kinases
Authors: Wong Lisa Epstein , Reynolds Albert B. , Dissanayaka Nadishani T. , Minden Audrey
Published: May 2010

Pak5 is a member of the Group B p21‐activated kinases, which are effectors of the Rho family GTPases Cdc42 and Rac. Pak5 has been shown to promote cytoskeletal reorganization, inducing filopodia formation and neurite outgrowth in neuroblastoma cells. In this study, we used affinity chromatography followed by SDS–PAGE and mass spectrometry to identify potential downstream effectors of Pak5. Using this approach, we isolated p120‐catenin (p120), a known regulator of cytoskeletal reorganization and Rho GTPases. Using co‐immunoprecipitation assays we found that p120 preferentially interacts with Pak5 among the Group B Paks. Results from immunofluorescence studies revealed that Pak5 and p120 co‐localize in cells. Both Pak5 and constitutively active Pak4, the founding member of the Group B Paks, directly phosphorylate p120 in vitro. The phosphorylation was shown by Western blot and immunofluorescence to take place specifically on serine 288. This study is the first report of an upstream serine/threonine kinase that phosphorylates p120. J. Cell. Biochem. 110: 1244–1254, 2010. Published 2010 Wiley‐Liss, Inc.
Beclin 1 self‐association is independent of autophagy induction by amino acid deprivation and rapamycin treatment
Authors: Adi‐Harel Shelly , Erlich Shlomit , Schmukler Eran , Cohen‐Kedar Sarit , Segev Oshik , Mizrachy Liat , Hirsch Joel A. , Pinkas‐Kramarski Ronit
Published: May 2010

Autophagy, a process of self‐digestion of cellular constituents, regulates the balance between protein synthesis and protein degradation. Beclin 1 represents an important component of the autophagic machinery. It interacts with proteins that positively regulate autophagy, such as Vps34, UVRAG, and Ambra1, as well as with anti‐apoptotic proteins such as Bcl‐2 via its BH3‐like domain to negatively regulate autophagy. Thus, Beclin 1 interactions with several proteins may regulate autophagy. To identify novel Beclin 1 interacting proteins, we utilized a GST‐Beclin 1 fusion protein. Using mass spectroscopic analysis, we identified Beclin 1 as a protein that interacts with GST‐Beclin 1. Further examination by cross linking and co‐immunoprecipitation experiments confirmed that Beclin 1 self‐interacts and that the coiled coil and the N‐terminal region of Beclin 1 contribute to its oligomerization. Importantly, overexpression of vps34, UVRAG, or Bcl‐xL, had no effect on Beclin 1 self‐interaction. Moreover, this self‐interaction was independent of autophagy induction by amino acid deprivation or rapamycin treatment. These results suggest that full‐length Beclin 1 is a stable oligomer under various conditions. Such an oligomer may provide a platform for further protein–protein interactions. J. Cell. Biochem. 110: 1262–1271, 2010. Published 2010 Wiley‐Liss, Inc.
Induction of nucleolin translocation by acharan sulfate in A549 human lung adenocarcinoma
Authors: Joo Eun Ji , Yang Hui , Park Youmie , Park Nam Young , Toida Toshihiko , Linhardt Robert J. , Kim Yeong Shik
Published: May 2010

Acharan sulfate (AS), isolated from the giant African snail Achatina fulica, is a novel glycosaminoglycan, consisting primarily of the repeating disaccharide structure α‐D‐N‐acetylglucosaminyl (1 → 4) 2‐sulfoiduronic acid. AS shows anti‐tumor activity in vitro and in vivo. Despite this activity, AS is only weakly cytotoxic towards cancer cells. We examine the interactions between AS and cell‐surface proteins in an effort to explain this anti‐tumor activity. Using flow cytometry and affinity column chromatography, we confirm that AS has strong affinity to specific cell‐surface proteins including nucleolin (NL) in A549 human lung adenocarcinomas. Surprisingly, we found the translocation of NL from nucleus to cytoplasm under the stimulation of AS (100 µg/ml) in vitro. Also, as NL exits the nucleus, the levels of growth factors such as bFGF and signaling cascade proteins, such as p38, p53, and pERK, are altered. These results suggest that the communication between AS and NL plays a critical role on signal transduction in tumor inhibition. J. Cell. Biochem. 110: 1272–1278, 2010. Published 2010 Wiley‐Liss, Inc.
Protection against cellular stress by 25‐hydroxyvitamin D3 in breast epithelial cells
Authors: Peng Xinjian , Vaishnav Avani , Murillo Genoveva , Alimirah Fatouma , Torres Karen E.O. , Mehta Rajendra G.
Published: May 2010

25‐Hydroxyvitamin D3 (25(OH)D3) is a prohormone and a major vitamin D metabolite. The discovery of (25(OH)D3) 1α‐hydroxylase in many vitamin D target organs has yielded an increased interest in defining the role(s) of 25(OH)D3 in these tissues. The etiology of cancer appears to be complex and multi‐factorial. Cellular stress (e.g., DNA damage, hypoxia, oncogene activation) has been identified as one of the key factors responsible for initiating the carcinogenesis process. In this study, we investigated whether 25(OH)D3 protects breast epithelial cells from cellular stress using an established breast epithelial cell line MCF12F. To better elucidate the role of 25(OH)D3 in the stress response, we used multiple in vitro stress models including serum starvation, hypoxia, oxidative stress, and apoptosis induction. Under all these stress conditions, 25(OH)D3 (250 nmol/L) treatment significantly protected cells against cell death. Low‐serum stress induced p53 expression accompanied with downregulation of PCNA, the presence of 25(OH)D3 consistently inhibited the alteration of p53 and PCNA, suggesting that these molecules were involved in the stress process and may be potential target genes of 25(OH)D3. miRNA microarray analysis demonstrated that stress induced by serum starvation caused significant alteration in the expression of multiple miRNAs including miR182, but the presence of 25(OH)D3 effectively reversed this alteration. These data suggest that there is a significant protective role for 25(OH)D3 against cellular stress in the breast epithelial cells and these effects may be mediated by altered miRNA expression. J. Cell. Biochem. 110: 1324–1333, 2010. © 2010 Wiley‐Liss, Inc.
Counting the cyclocized polyphenacenes
Authors: Qian Jianguo , Zhang Fuji
Published: May 2010

In general the cyclocized polyphenacenes have a geometric nonplanar structure. This article gives an explicit expression of the counting formula for the two types of cyclocized polyphenacenes, viz., the belt‐type and Möbius type, respectively. The result implies that almost all the belt‐type cyclocized polyphenacenes, roughly speaking, are chiral if they are sufficiently large. The numerical results for these two types with the number of phenyl rings from 3 up to 18 are listed, as an example. © 2010 Wiley Periodicals, Inc. J Comput Chem 2010
An optimum strategy for solution chemistry using semiempirical molecular orbital method. II. Primary importance of reproducing electrostatic interaction in the QM/MM framework
Authors: Koyano Yoshiyuki , Takenaka Norio , Nakagawa Yukinori , Nagaoka Masataka
Published: May 2010

For the purpose of executing direct dynamic and statistical calculation of chemical reactions in solution, we proposed an optimum strategy using semiempirical molecular orbital (MO) method with neglect of diatomic differential overlap (NDDO) approximation with specific solution reaction parameters (SSRPs), that is, the NDDO‐SSRP method. It has been further extended to develop the NDDO‐MAIS‐SSRP method, which is the NDDO‐SSRP method reinforced with the method adopted for intermolecular studies (MAIS), to correct the description of the intermolecular core–core repulsion interaction energy. In this strategy, the empirical parameters of the semiempirical MO method are optimized individually for a target chemically reacting molecular system by reference to the ab initio MO calculation data for a lot of instantaneous geometries on the potential energy surface near the reaction path. For demonstration, the NDDO‐MAIS‐SSRP method was applied, within the QM/MM framework, to a molecular cluster, that is, a couple of a QM solute NH3H2O molecule pair and a MM solvent H2O molecule. The NDDO‐MAIS‐SSRP method can reproduce the electrostatic energy in the region R > 4.0 Å, though the electrostatic energy shows large difference with those of MP2 level calculations in the region R < 4.0 Å in some cases. Both the NDDO‐SSRP and the NDDO‐MAIS‐SSRP methods could promise in the dynamical application to chemical reaction in solution (Takenaka et al., Chem Phys Lett 2010, 485, 119; Koyano et al., Bull Chem Soc Jpn, in press). © 2010 Wiley Periodicals, Inc. J Comput Chem 2010
The role of water in the proton transfer reaction mechanism in tryptophan
Authors: Vöhringer‐Martinez Esteban , Toro‐Labbé Alejandro
Published: May 2010

The role of water in the proton transfer mechanism between the carboxylic and the amino group in tryptophan was studied through the direct, intramolecular reaction in presence of a continuum and the single water molecule mediated, intermolecular reaction in vacuum and in presence of a continuum. The introduction of the continuum reduced the activation barriers for the proton transfer from the neutral form and stabilized the zwitterion in both cases. The reaction force and the reaction electronic flux along the intrinsic reaction coordinate allowed in combination with a Natural Bond Order Analysis a more detailed description of the influence of water on the reaction mechanism. Represented as a continuum model, water reduced the energy required for bond reorganization and did not alter the first part of the intermolecular reaction, characterized through the approximation of the water molecule to the functional groups of the amino acid and a polarization of the system. The absence of a water molecule in the intramolecular proton transfer with continuum changed the reaction coordinate to a reduction of the angle between the functional groups of the amino acid leaving the energy required for bond formation unaffected. Thus, the smaller activation barrier obtained in the direct intramolecular proton transfer with continuum model in comparison to the water mediated reaction, originates from the energetically more favorable angle reduction in comparison the approximation of a water molecule. © 2010 Wiley Periodicals, Inc. J Comput Chem 2010
Electronic structures and nonlinear optical properties of highly deformed halofullerenes C3v C60F18 and D3d C60Cl30
Authors: Tang Shu‐Wei , Feng Jing‐Dong , Qiu Yong‐Qing , Sun Hao , Wang Feng‐Di , Chang Ying‐Fei , Wang Rong‐Shun
Published: May 2010

Electronic structures and nonlinear optical properties of two highly deformed halofullerenes C3v C60F18 and D3d C60Cl30 have been systematically studied by means of density functional theory. The large energy gaps (3.62 and 2.61 eV) between the highest occupied and lowest unoccupied molecular orbitals (HOMOs and LUMOs) and the strong aromatic character (with nucleus‐independent chemical shifts varying from −15.08 to −23.71 ppm) of C60F18 and C60Cl30 indicate their high stabilities. Further investigations of electronic property show that C60F18 and C60Cl30 could be excellent electron acceptors for potential photonic/photovoltaic applications in consequence of their large vertical electron affinities. The density of states and frontier molecular orbitals are also calculated, which present that HOMOs and LUMOs are mainly distributed in the tortoise shell subunit of C60F18 and the aromatic [18] trannulene ring of C60Cl30, and the influence from halogen atoms is secondary. In addition, the static linear polarizability $ \left\langle \alpha \right\rangle $ and second‐order hyperpolarizability $ \left\langle \gamma \right\rangle $ of C60F18 and C60Cl30 are calculated using finite‐field approach. The values of $ \left\langle \alpha \right\rangle $ and $ \left\langle \gamma \right\rangle $ for C60F18 and C60Cl30 molecules are significantly larger than those of C60 because of their lower symmetric structures and high delocalization of π electrons. © 2010 Wiley Periodicals, Inc. J Comput Chem 2010
Prolonged survival and improved glycemia in BioBreeding diabetic rats after early sustained exposure to glucagon‐like peptide 1
Authors: Yanay Ofer , Moralejo Daniel , Kernan Kelly , Brzezinski Margaret , Fuller Jessica M. , Barton Randall W. , Lernmark Ake , Osborne William R.
Published: May 2010

Background

Type 1 diabetes (T1D) in both humans and BioBreeding (BB) rats is an autoimmune disease that results in complete destruction of islets and insulin dependency for life. Glucagon‐like peptide 1 (GLP‐1) promotes β cell proliferation and neogenesis and has a potent insulinotropic effect. We hypothesized that the expression of GLP‐1 before disease onset would increase islet mass, delay diabetes and prolong survival of BB rats.

Methods

Vascular smooth muscle cells retrovirally transduced to secrete GLP‐1 were seeded into TheraCyte™ encapsulation devices, implanted subcutaneously, and rats were monitored for diabetes.

Results

In untreated control rats, plasma GLP‐1 levels were 34.5–39.5 pmol/l, whereas, in treated rats, plasma levels were elevated, in the range 90–250.4 pmol/l. Hypoglycemia was not detected and this was anticipated from the glucose‐regulated action of GLP‐1. Diabetes onset (mean ± SEM) in untreated rats occurred at 56.5 ± 0.6 days (n = 6) and, in GLP‐1‐treated rats, was delayed until 76.4 ± 3.3 days (n = 5) (p < 0.001). After disease onset, untreated control rats showed a rapid weight loss and elevated blood glucose (>650 mg/dl) and did not survive beyond 11 days. At 5 days after diabetes onset, insulin‐secreting islets were absent in untreated rats. By contrast, treated rats maintained weight for up to 143 days of age and showed insulin‐secreting β cells.

Conclusions

Sustained GLP‐1 expression delivered by encapsulated cells before diabetes onset in BB rats showed an improved clinical outcome, suggesting the potential for treating patients using long lasting GLP‐1 analogs. Copyright © 2010 John Wiley & Sons, Ltd.
10th international symposium on the synthesis and applications of isotopes and isotopically labelled compounds—new analytical methods Session 8, Wednesday, June 17, 2009
Authors: Clodfelter Dean , Rees Anthony
Published: May 2010

Abstract: Different methods for the analysis of radiolabelled compounds are discussed as well as their potential uses in a wide range of activities such as drug discovery and ultra low level background LSC in a salt mine. Copyright © 2010 John Wiley & Sons, Ltd.
Chirally dimorphic male genitalia in praying mantids (Ciulfina: Liturgusidae)
Authors: Holwell Gregory I. , Herberstein Marie E.
Published: May 2010

Although male polymorphisms occur widely in nature and have received considerable recent attention from studies of alternative mating strategies, male genital polymorphisms are less well known. Here, we describe a dimorphism in the orientation of the male genitalic complex of the praying mantid genus Ciulfina. Populations of Ciulfina species vary in the proportion of males with dextral (right‐oriented) and sinistral (left‐oriented) genitalia, ranging from directional asymmetry (single orientation only) to apparent antisymmetry (equal proportions of both orientations). The proportion of dextral males varied between species (C. baldersoni: 46%; C. rentzi: 24%; C. klassi: 100%; C. biseriata: 83%) and between populations. We used elliptic Fourier analysis to quantify shape and size variation between the genitalia of dextral and sinistral males and determined that the two forms were mirror images of one another in two species. We found that the level of mechanical reproductive isolation between heterospecific populations of opposite genital orientation was no greater than that between heterospecific populations with the same orientation or of mixed orientation. Genital orientation therefore did not influence premating isolation between these species, despite complete postmating isolation. The geographic proximity of populations to heterospecifics also showed no particular pattern with respect to genital orientation. These results suggest that reversible trait asymmetry in Ciulfina is not driven by reproductive isolation, and add to the growing evidence against the species isolation hypothesis for rapid genital evolution. J. Morphol. 271:1176–1184, 2010. © 2010 Wiley‐Liss, Inc.
Fragmentation behavior of Amadori‐peptides obtained by non‐enzymatic glycosylation of lysine residues with ADP‐ribose in tandem mass spectrometry
Authors: Fedorova Maria , Frolov Andrej , Hoffmann Ralf
Published: May 2010

Mono‐ and poly‐adenosine diphosphate (ADP)‐ribosylation are common post‐translational modifications incorporated by sequence‐specific enzymes at, predominantly, arginine, asparagine, glutamic acid or aspartic acid residues, whereas non‐enzymatic ADP‐ribosylation (glycation) modifies lysine and cysteine residues. These glycated proteins and peptides (Amadori‐compounds) are commonly found in organisms, but have so far not been investigated to any great degree. In this study, we have analyzed their fragmentation characteristics using different mass spectrometry (MS) techniques. In matrix‐assisted laser desorption/ionization (MALDI)‐MS, the ADP‐ribosyl group was cleaved, almost completely, at the pyrophosphate bond by in‐source decay. In contrast, this cleavage was very weak in electrospray ionization (ESI)‐MS. The same fragmentation site also dominated the MALDI‐PSD (post‐source decay) and ESI‐CID (collision‐induced dissociation) mass spectra. The remaining phospho‐ribosyl group (formed by the loss of adenosine monophosphate) was stable, providing a direct and reliable identification of the modification site via the b‐ and y‐ion series. Cleavage of the ADP‐ribose pyrophosphate bond under CID conditions gives access to both neutral loss (347.10 u) and precursor‐ion scans (m/z 348.08), and thereby permits the identification of ADP‐ribosylated peptides in complex mixtures with high sensitivity and specificity. With electron transfer dissociation (ETD), the ADP‐ribosyl group was stable, providing ADP‐ribosylated c‐ and z‐ions, and thus allowing reliable sequence analyses. Copyright © 2010 John Wiley & Sons, Ltd.
Supply‐side perspectives on ecotourism in Northern Thailand
Authors: Kontogeorgopoulos Nick , Chulikavit Kittinoot
Published: May 2010

This study provides a supply‐side perspective on ecotourism by exploring the ways in which travel agents and tour operators in Chiang Mai, Thailand conceptualise, prioritise and furnish ecotourism. Although travel agents and tour operators serve as crucial intermediaries between tourists and destinations, the ecotourism literature has largely ignored the ways in which retailers and suppliers of tourism experience approach and define ecotourism. Using quantitative data gathered from 300 travel agents and tour operators, this paper illustrates that the conceptualisation of ecotourism among agents and operators in Chiang Mai is expansive, flexible and, in some ways, internally contradictory. Copyright © 2010 John Wiley & Sons, Ltd.
Electrospun Mats from Styrene/Maleic Anhydride Copolymers: Modification with Amines and Assessment of Antimicrobial Activity
Authors: Ignatova Milena , Stoilova Olya , Manolova Nevena , Markova Nadya , Rashkov Iliya
Published: May 2010

New antimicrobial microfibrous electrospun mats from styrene/maleic anhydride copolymers were prepared. Two approaches were applied: (i) grafting of poly(propylene glycol) monoamine (Jeffamine® M‐600) on the mats followed by formation of complex with iodine; (ii) modification of the mats with amines of 8‐hydroxyquinoline or biguanide type with antimicrobial activity. Microbiological screening against S. aureus, E. coli and C. albicans revealed that both the formation of complex with iodine and the covalent attachment of 5‐amino‐8‐hydroxyquinoline or of chlorhexidine impart high antimicrobial activity to the mats. In addition, S. aureus bacteria did not adhere to modified mats.

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Liquid, Injectable, Hydrophobic and Biodegradable Polymers as Drug Delivery Vehicles
Authors: Amsden Brian G.
Published: May 2010

New delivery approaches to achieve minimally invasive, sustained and local release of drugs are needed for more effective treatment of conditions such as cancer and ischemia. Hydrophobic, biodegradable, liquid injectable polymers possess a number of potential advantages for this purpose. This review examines various approaches that have been explored for the preparation of these types of polymers, their ability to control the release of various drugs ranging from low‐molecular‐weight hydrophobic compounds to protein therapeutics, and finally their degradation rates and the tissue response to them upon implantation.

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Correlation between Composition, Structure and Properties of Poly(lactic acid)/Polyadipate‐Based Nano‐Biocomposites
Authors: Martino Verónica P. , Ruseckaite Roxana A. , Jiménez Alfonso , Averous Luc
Published: May 2010

Poly(lactic acid) plasticized with 15 and 20 wt.‐% of polyadipate was melt‐blended with different amounts of an O‐MMT (1–5 wt.‐%) to prepare nano‐biocomposites. The effect of plasticizer and nanofiller contents on the morphology and on thermal, mechanical and barrier properties of PLA‐based nano‐biocomposites was evaluated in order to understand their structure‐properties relationships. The oxygen transmission rate was notably reduced (around 45%) with increasing amount of clay due to an increased tortuosity. However, for clay concentrations above 3 wt.‐%, a significant detriment in ductile properties could also be observed. For a given amount of nanofiller, the increasing plasticizer concentration improved the clay dispersion through the polymeric matrix.

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Chemistry on Electrospun Polymeric Nanofibers: Merely Routine Chemistry or a Real Challenge?
Authors: Agarwal Seema , Wendorff Joachim H. , Greiner Andreas
Published: May 2010

Nanofiber‐based non‐wovens can be prepared by electrospinning. The chemical modification of such nanofibers or chemistry using nanofibers opens a multitude of application areas and challenges. A wealth of chemistry has been elaborated in recent years on and with electrospun nanofibers. Known methods as well as new methods have been applied to modify the electrospun nanofibers and thereby generate new materials and new functionalities. This Review summarizes and sorts the chemistry that has been reported in conjunction with electrospun nanofibers. The major focus is on catalysis and nanofibers, enzymes and nanofibers, surface modification for biomedical and specialty applications, coatings of fibers, crosslinking, and bulk modifications. A critical focus is on the question: what could make chemistry on or with nanofibers different from bulk chemistry?

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Block Copolymer Micelles with Near Infrared Metal Phthalocyanine Dyes for Laser Induced Writing
Authors: Acharya Himadri , Yoon Bokyung , Park Youn Jung , Bae Insung , Park Cheolmin
Published: May 2010

A route has been developed to disperse metal‐containing phthalocyanine dyes in a non‐polar medium based on amphiphilic block copolymer micelles of poly[styrene‐block‐(4‐vinylpyridine)] (PS‐b‐P4VP) and poly[styrene‐block‐(acrylic acid)] (PS‐b‐PAA) copolymers. Polar P4VP and PAA efficiently encapsulate cobalt(II), manganese(II), and nickel(II) phthalocyanine dyes by axial coordination of nitrogen and µ‐oxo bridged dimerization with the transition metals, respectively. Good dispersion of the dyes is confirmed by the linear enhancement of Q‐bands in UV–vis absorption spectra with dye concentration. A thin monolayered PS‐b‐P4VP micelle film that contained a nickel(II) phthalocyanine dye which efficiently adsorbs a laser beam on a localized area to generate a local heat higher than the glass transition temperatures of both blocks. One‐dimensional laser writing on the dye‐containing film allows the fabrication of a few submicrometer wide line patterns in which the self‐assembled nanostructure of the block copolymer is modified by the directional heat arising from laser scanning.

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Organoboron Polymers for Photovoltaic Bulk Heterojunctions
Authors: Cataldo Sebastiano , Fabiano Simone , Ferrante Francesco , Previti Francesco , Patanè Salvatore , Pignataro Bruno
Published: May 2010

We report on the application of three‐coordinate organoboron polymers, inherently strong electron acceptors, in flexible photovoltaic (PV) cells. Poly[(1,4‐divinylenephenylene)(2,4,6‐triisopropylphenylborane)] (PDB) has been blended with poly(3‐hexylthiophene‐2,5‐diyl) (P3HT) to form a thin film bulk heterojunction (BHJ) on PET/ITO substrates. Morphology may be modulated to give a high percentage of domains (10–20 nm in size) allowing exciton separation. The photoelectric properties of the BHJs in devices with aluminium back electrodes were imaged by light beam induced current (LBIC) and light beam induced voltage (LBIV) techniques. Open circuit voltages, short circuit currents and overall external quantum efficiencies obtained are among the highest reported for all‐polymer PV cells.

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Facile Synthesis and Polymerization of 2,6‐Difluoro‐2′‐sulfobenzophenone for Aromatic Proton Conducting Ionomers with Pendant Sulfobenzoyl Groups
Authors: Jutemar Elin Persson , Takamuku Shogo , Jannasch Patric
Published: May 2010

The lithium salt of 2,6‐difluoro‐2′‐sulfobenzophenone was conveniently synthesized in one‐pot by reacting 2,6‐difluorophenyllithium with 2‐sulfobenzoic acid cyclic anhydride in THF at −70 °C whereafter the product crystallized out of solution. A poly(arylene ether) and a poly(arylene sulfide) were prepared by polycondensation reactions to demonstrate the reactivity and efficacy of this new monomer to produce sulfonated high‐molecular weight aromatic polymers for fuel cell proton‐exchange membranes. This work demonstrated that organolithium chemistry may offer versatile and straightforward pathways to new functional monomers with fluorine atoms activated for nucleophilic aromatic substitution reactions.

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