bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sesquiterpene Lactones from Daucus glaber
Authors: Sallam Amal A. , Hitotsuyanagi Yukio , Mansour El‐Sayed S. , Ahmed Atallah F. , Gedara Sahar , Fukaya Haruhiko , Takeya Koichi 
Published: January 2010

AbstractSix new sesquiterpene lactone esters, daucoguaianolactones A–F (1–6), and one new sesquiterpene lactone, daucoeudesmanolactone A (7) were isolated from the leaves and stems of Daucus glaber (Forssk.) Thell., along with the known sesquiterpene lactones talasins A and B and badkhysin. The structures of 1–6 were established on the basis of extensive 1D‐ and 2D‐NMR spectroscopic studies and that of 7 by X‐ray crystallography. Compounds 4, 7, and talasins A and B showed moderate cytotoxicity against P‐388 leukemia cells.
Two New Alkaloids from Stemona tuberosa
Authors: Zhong Ying , Gao Ying , Guo Qiu‐Ping , Li Wei‐Min 
Published: January 2010

AbstractTwo new alkaloids, named tuberostemoninol A (1) and tuberostemoninol B (2), along with the known compounds tuberostemoninol (3) and bisdehydroneotuberostemonine (4), were isolated from Stemona tuberosa Lour. The structures were elucidated by means of spectroscopic analyses, including 1D‐ and 2D‐NMR experiments. The four alkaloids 1–4 were analyzed by on‐line high‐performance liquid chromatography/electrospray‐ionization mass spectrometry (HPLC/ESI‐MS), and their fragmentation pathways were found to be similar. Compounds 1, 2, and 3 are isomers with the same molecular mass but which eluted at different retention times.
Stereoselective Total Synthesis of (11β)‐11‐Methoxycurvularin
Authors: Rajesh Karuturi , Suresh Vangaru , Selvam Jondoss Jon Paul , Babu Dokuburra Chanti , Venkateswarlu Yenamandra 
Published: January 2010

AbstractA simple and highly efficient stereoselective total synthesis of (11β)‐11‐methoxycurvularin (5), a polyketide natural product, was achieved. The synthesis commenced with a Cu‐mediated regioselective opening of (2S)‐2‐methyloxirane (6) and comprised a Keck asymmetric allylation and intramolecular Friedel–Crafts acylation as key steps (Scheme 2).
Secoiridoid Constituents from the Fruits of Ligustrum lucidum
Authors: Yang Nian‐Yun , Xu Xiao‐Hua , Ren Dong‐Chun , Duan Jin‐Ao , Xie Ning , Tian Li‐Juan , Qian Shi‐Hui 
Published: January 2010

AbstractFour new secoiridiod glucosides, p‐hydroxyphenethyl 7‐β‐D‐glucosideelenolic acid ester (1), 6′‐elenolylnicotiflorine (2), 6′′′‐acetylnicotiflorine (3), and oleoside 7‐ethyl 11‐methyl ester (4), as well as six known glucosides, nuezhenide (5), Gl‐3 (6), nicotiflorine (7), isonuezhenide (8), neonuezhenide (9), and oleoside 11‐methyl ester (10) were isolated from the fruits of Ligustrum lucidum. Their structures were elucidated by spectroscopic methods. Compound 4 was an artifact produced during extraction.
Conformational Studies of (±)‐11,12‐Didehydro‐11‐deoxycorynoline and (+)‐11,13‐Didehydro‐11‐deoxychelidonine, Hexahydrobenzo[c]phenanthridine‐Type Alkaloid Derivatives, by X‐Ray Crystal Structure and NMR Analyses
Authors: Kamigauchi Miyoko , Maekawa Yukiko , Tode Chisato , In Yasuko , Ishida Toshimasa 
Published: January 2010

AbstractThe X‐ray crystal analyses of the two 11‐deoxy‐didehydrohexahydrobenzo[c]phenanthridine‐type alkaloid derivatives 3 and 4, derived from (±)‐corynoline (1) and (+)‐chelidonine (2), established their structures as (±)‐(5bRS,12bRS)‐5b,12b,13,14‐tetrahydro‐5b,13‐dimethyl[1,3]benzodioxolo[5,6‐c]‐1,3‐dioxolo[4,5‐i]phenanthridine (3) and (+)‐rel‐(12bR)‐7,12b,13,14‐tetrahydro‐13‐methyl[1,3]benzodioxolo[5,6‐c]‐1,3‐dioxolo[4,5‐i]phenanthridine (4). The conformations of 3 and 4 in CDCl3 were determined on the basis of 1H‐ and 13C‐NMR spectroscopy.
Catalytic Performance of Ruthenium‐Supported Ionic‐Liquid Catalysts in Sustainable Synthesis of Macrocyclic Lactones
Authors: Hagiwara Hisahiro , Nakamura Tomomi , Okunaka Naotaro , Hoshi Takashi , Suzuki Toshio 
Published: January 2010

AbstractThirteen‐ to eighteen‐membered lactones were synthesized by ring‐closing olefin‐metathesis reactions of bis‐olefins with heterogeneous Grubbs‐supported ionic‐liquid catalysts (SILCs), in which homogeneous Grubbs catalysts were confined in pores of alumina with the aid of an ionic liquid. The Grubbs‐SILCs exhibited higher catalytic performance than their homogeneous counterparts and could be repeatedly recovered by simple filtration and re‐used several times.
Fibromyalgia—pathways and neurotransmitters
Authors: Stahl Stephen M. 
Published: January 2010

AbstractFibromyalgia is a syndrome of widespread chronic pain associated with sleep disorders, depressed mood, cognitive impairment and fatigue. Its etiology and pharmacopathology are poorly understood but it is thought to result from a dysfunction of central pain processing mechanisms leading to generalised pain sensitisation. Pain perception is the result of a bidirectional process of ascending and descending pathways. Nociceptive input from peripheral afferent neurons is sent via the dorsal horn of the spinal cord to the higher brain centres involved in pain perception. Some descending inhibitory projections to the spinal cord attenuate the nociceptive effects. Numerous neurotransmitters including serotonin, dopamine, noradrenaline and substance P are involved in these processes. In other neuronal pathways in the brain, the same neurotransmitters are involved in mood control, sleep regulation and cognitive function providing a neurochemical substrate for the wide range of symptoms seen in fibromyalgia. Attenuation of neuronal hyperactivity through ligands acting at the α2‐δ subunits of voltage‐dependent calcium channels and increased inhibitory activity of the descending pathways by inhibition of serotonin and noradrenaline reuptake are two mechanisms that are currently exploited by new medication for the treatment of fibromyalgia. Copyright © 2009 John Wiley & Sons, Ltd.
p16INK4a overexpression predicts translational active human papillomavirus infection in tonsillar cancer
Authors: Hoffmann Markus , Ihloff Anna Sophie , Görögh Tibor , Weise Jan B. , Fazel Asita , Krams Matthias , Rittgen Werner , Schwarz Elisabeth , Kahn Tomas 
Published: January 2010

AbstractThe causal role of human papillomaviruses (HPV) in squamous cell carcinogenesis of tonsillar cancers (TSCC) depends on the activity of the viral oncoproteins E6 and E7, leading to inactivation of the cellular tumor suppressor p53 and the retinoblastoma gene product pRb. Because of the negative feedback mechanisms, the pRb inactivation causes an increase of the inhibitor of the cyclin‐dependent kinases p16INK4a. In 39 TSCC specimens, genotyping based on the amplification of HPV DNA was carried out using PCR by applying HPV type‐specific oligonucleotides. Subsequently, amplicons were hybridised with fluorescence‐labeled complementary probes using the Southern blot technology. For HPV E6/E7 mRNA expression, Northern hybridization and RT‐PCR were performed, and for p16INK4a detection, immunohistochemistry was performed. With 21/39 (53%) HPV‐positives, the detection rate is within the range that can be expected in TSCC. The E6/E7 oncogene mRNA was detectable in 11 cases, 10 of which showed positive signals after p16INK4a staining. Albeit the small study group was investigated, the correlation of the HPV DNA status with the p16INK4a expression was of statistical significance (p = 0.02). Kaplan‐Meier estimations revealed better survival outcome for patients with HPV‐positive tumors with detectable E6/E7 mRNA and p16INK4a overexpression (p = 0.02, median observation time 29 months). As mRNA expression tests are not routinely available in many clinical diagnostic laboratories, and based on the high correlation of p16INK4a staining with HPV E6/E7 mRNA expression, in conclusion we suggest for a deeper exploration for the use of p16INK4a as a surrogate marker with the potential to impact the standard of care of HPV DNA‐positive head and neck carcinomas.
Tumors exposed to acute cyclic hypoxic stress show enhanced angiogenesis, perfusion and metastatic dissemination
Authors: Rofstad Einar K. , Gaustad Jon‐Vidar , Egeland Tormod A.M. , Mathiesen Berit , Galappathi Kanthi 
Published: January 2010

AbstractClinical studies have shown that patients with highly hypoxic primary tumors may have poor disease‐free and overall survival rates. Studies of experimental tumors have revealed that acutely hypoxic cells may be more metastatic than normoxic or chronically hypoxic cells. In the present work, causal relations between acute cyclic hypoxia and metastasis were studied by periodically exposing BALB/c nu/nu mice bearing A‐07 human melanoma xenografts to a low oxygen atmosphere. The hypoxia treatment consisted of 12 cycles of 10 min of 8% O2 in N2 followed by 10 min of air for a total of 4 hr, began on the first day after tumor cell inoculation and was given daily until the tumors reached a volume of 100 mm3. Twenty‐four hours after the last hypoxia exposure, the primary tumors were subjected to dynamic contrast‐enhanced magnetic resonance imaging for assessment of blood perfusion before being resected and processed for immunohistochemical examinations of microvascular density and expression of proangiogenic factors. Mice exposed to acute cyclic hypoxia showed increased incidence of pulmonary metastases, and the primary tumors of these mice showed increased blood perfusion, microvascular density and vascular endothelial growth factor‐A (VEGF‐A) expression; whereas, the expression of interleukin‐8, platelet‐derived endothelial cell growth factor and basic fibroblast growth factor was unchanged. The increased pulmonary metastasis was most likely a consequence of hypoxia‐induced VEGF‐A upregulation, which resulted in increased angiogenic activity and blood perfusion in the primary tumor and thus facilitated tumor cell intravasation and hematogenous transport into the general circulation.
CIITA‐driven MHC‐II positive tumor cells: Preventive vaccines and superior generators of antitumor CD4+ T lymphocytes for immunotherapy
Authors: Frangione Valeria , Mortara Lorenzo , Castellani Patrizia , De Lerma Barbaro Andrea , Accolla Roberto S. 
Published: January 2010

AbstractIn our study, we have investigated whether tumors of distinct histological origin can be rejected if expressing CIITA‐driven MHC class II molecules. Moreover, we assessed whether antitumor lymphocytes generated by this approach could be used as an immunotherapeutic tool for established cancers. Stable CIITA‐transfectants of C51colon adenocarcinoma, RENCA renal adenocarcinoma, WEHI‐164 sarcoma as well as TS/A mammary adenocarcinoma were generated. Tumor cells transfectants were injected in vivo, and their growth kinetics and recipient's immune response were analyzed. Tumor rejection and/or retardation of growth was found for the first 3 CIITA‐transfected tumor cell lines and confirmed for TS/A‐CIITA. Animals rejecting CIITA‐transfected tumors acquired specific immunological memory as demonstrated by resistance to challenge with parental tumors. Adoptive cell transfer experiments demonstrated that tumor immunity correlates with the efficient priming of CD4+ T helper cells and the consequent activation of CD8+ T lymphocytes. T cells from TS/A‐vaccinated mice were used in an adoptive immunotherapy model of established tumors. The results showed the cure at early stages and significantly prolonged survival at later stages of tumor progression. Importantly, CD4+ T cells were clearly superior to CD8+ T cells in antitumor protective function. Interestingly, the protective phenotype was associated to both a Th1 and Th2 polarization of the immune effectors. These results establish the general application of our tumor vaccine model and disclose the additional application of this strategy for producing better lymphocyte effectors for adoptive antitumor immunotherapy.
Hormone replacement therapy and incidence of central nervous system tumours in the Million Women Study
Authors: Benson Victoria S. , Pirie Kirstin , Green Jane , Bull Diana , Casabonne Delphine , Reeves Gillian K. , Beral Valerie ,   for the Million Women Study Collaborators
Published: January 2010

AbstractWe examined the relation between the use of hormone replacement therapy (HRT) and the incidence of central nervous system (CNS) tumours in a large prospective study of 1,147,894 postmenopausal women. Women were aged 56.6 years on average at entry, and HRT use was recorded at recruitment and updated, where possible, about 3 years later. During a mean follow‐up of 5.3 years per woman, 1,266 CNS tumours were diagnosed, including 557 gliomas, 311 meningiomas and 117 acoustic neuromas. Compared with never users of HRT, the relative risks (RRs) for all incident CNS tumours, gliomas, meningiomas and acoustic neuromas in current users of HRT were 1.20 (95% CI: 1.05–1.36), 1.09 (95% CI: 0.89–1.32), 1.34 (95% CI: 1.03–1.75) and 1.58 (95% CI: 1.02–2.45), respectively, and there was no significant difference in the relative risks by tumour type (heterogeneity p = 0.2). In past users of HRT the relative risk was 1.07 (95% CI: 0.93–1.24) for all CNS tumours. Among current users of HRT, there was significant heterogeneity by the type of HRT with the users of oestrogen‐only HRT at higher risk of all CNS tumours than users of oestrogen–progestagen HRT (RR = 1.42, 95% CI: 1.21–1.67 versus RR = 0.97, 95% CI: 0.82–1.16) (heterogeneity p < 0.001). Among current users of oestrogen‐only and oestrogen–progestagen HRT, there was no significant heterogeneity by duration of use, hormonal constituent or mode of administration of HRT.
Tailoring the mechanical properties of 3D‐designed poly(glycerol sebacate) scaffolds for cartilage applications
Authors: Kemppainen Jessica M. , Hollister Scott J. 
Published: January 2010

AbstractMatching tissue engineering scaffold modulus to that of native tissue is highly desirable. Effective scaffold modulus can be altered through changes in base material modulus and/or scaffold pore architecture. Because the latter may be restricted by tissue in‐growth requirements, it is advantageous to be able to alter the base material modulus of a chosen scaffold material. Here, we show that the bulk modulus of poly(glycerol sebacate) (PGS) can be changed by varying molar ratios during prepolymer synthesis and by varying curing time. We go on to show that PGS can be used to create 3D designed scaffolds via solid freeform fabrication methods with modulus values that fall within the ranges of native articular cartilage equilibrium modulus. Furthermore, using base material modulus inputs, homogenization finite element analysis can effectively predict the tangent modulus of PGS scaffold designs, which provides a significant advantage for designing new cartilage regeneration scaffolds. Lastly, we demonstrate that this relatively new biomedical material supports cartilaginous matrix production by chondrocytes in vitro. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Moisture‐cured silicone–urethanes—Candidate materials for tissue engineering: A biocompatibility study in vitro
Authors: Mrówka P. , Kozakiewicz J. , Jurkowska A. , Sienkiewicz E. , Przybylski J. , Lewandowski Z. , Przybylski J. , Lewandowska‐Szumieł M. 
Published: January 2010

AbstractThis study was performed to verify the response of human bone‐derived cells (HBDCs) to moisture‐cured silicone–urethanes (mcSUUs) in vitro, as the first step toward using them as scaffolds for bone tissue engineering. Good surgical handling, tissue cavity filling, stable mechanical properties, and potentially improved oxygen supply to cells after implantation justify the investigation of these nondegradable elastomers. A set of various mcSUUs were obtained by moisture‐curing NCO‐terminated prepolymers, synthesized from oligomeric siloxane diols of two different oligosiloxane chain lengths, and two different diisocyanates (MDI and IPDI), using two different NCO/OH molar ratios. Dibutyltindilaurate (DBTL) or N‐dimethylethanolamine (N‐met) served as catalysts. After 7 days of culture, cell number, viability, and alkaline phosphatase (ALP) activity were determined, and after 21 days, cell viability and collagen production were determined. Material characteristics significantly influenced the cell response. The mcSUUs prepared with DBTL (widely used in the syntheses of biomaterials) were cytotoxic. The MDI‐based mcSUUs were significantly more favored by HBDCs than the IPDI‐based ones in all performed tests. MDI‐based material with low 2/1 NCO/OH and short chain length was the best support for cells, comparable with tissue‐culture polystyrene (with ALP activity even higher). HBDCs cultured on porous scaffolds from this mcSUU produced a tissue‐like structure in culture. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
In vivo outcomes of tissue‐engineered osteochondral grafts
Authors: Bal B. Sonny , Rahaman Mohamed N. , Jayabalan Prakash , Kuroki Keiichi , Cockrell Mary K. , Yao Jian Q. , Cook James L. 
Published: January 2010

AbstractTissue‐engineered osteochondral grafts have been synthesized from a variety of materials, with some success at repairing chondral defects in animal models. We hypothesized that in tissue‐engineered osteochondral grafts synthesized by bonding mesenchymal stem cell‐loaded hydrogels to a porous material, the choice of the porous scaffold would affect graft healing to host bone, and the quality of cell restoration at the hyaline cartilage surface. Bone marrow‐derived allogeneic mesenchymal stem cells were suspended in hydrogels that were attached to cylinders of porous tantalum metal, allograft bone, or a bioactive glass. The tissue‐engineered osteochondral grafts, thus created were implanted into experimental defects in rabbit knees. Subchondral bone restoration, defect fill, bone ingrowth‐implant integration, and articular tissue quality were compared between the three subchondral materials at 6 and 12 weeks. Bioactive glass and porous tantalum were superior to bone allograft in integrating to adjacent host bone, regenerating hyaline‐like tissue at the graft surface, and expressing type II collagen in the articular cartilage. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
Synthesis, in vitro hydroxyapatite forming ability, and cytocompatibility of strontium silicate powders
Authors: Zhang Meili , Zhai Wanyin , Lin Kaili , Pan Haobo , Lu William , Chang Jiang 
Published: January 2010

AbstractPhase‐pure strontium silicate (SrSiO3) powders were synthesized by chemical precipitation method. In vitro bioactivity of the powders were evaluated by examining the hydroxyapatite forming ability on their surface soaking simulated body fluid for various periods. The results showed that SrSiO3 could induce hydroxy carbonate apatite formation after soaking for 7 days. Both L929 and rabbit bone marrow stromal cells (rMSCs) were used to test the in vitro cytocompatibility of SrSiO3. L929 culture experiment showed that the ionic product of SrSiO3 did not exhibit cytotoxicity except at high ion concentrations (Si 3.75 mM and Sr 0.12 mM). Moreover, at certain ion concentrations (Si 1.87–0.12 mM and Sr 0.12–3.75 × 10−3 mM), the ionic product of SrSiO3 stimulated the proliferation of rMSCs. All the results indicated that SrSiO3 might be used as a new bioactive material for bone regeneration applications. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
Effect of stem preheating and precooling on residual stress formation at stem/cement interface for cemented hip implants
Authors: Madrala A. , Nuño N. 
Published: January 2010

AbstractPMMA polymerization is an exothermic phenomenon during which stresses and porosity are observed. An experimental model is devised to directly measure radial forces, to be converted to radial stresses, at the stem/cement interface, and temperatures at both interfaces during cement curing. The effects of stem and bone cement initial temperatures (preheating or precooling vs. room temperature) as well as mixing method (hand vs. vacuum mixing) and cement type (Simplex P vs. Palacos R) on radial stress and temperatures are investigated. Compressive radial residual stresses at the stem/cement interface are measured for hand mixed PMMA with preheated stem, with a maximum magnitude of 1.0 MPa. No radial residual stresses are observed when the stem is initially at room temperature or precooled, suggesting that during curing, bone cement can polymerize away from the stem/cement interface generating radial stress in tension or gaps. The results demonstrate the reverse direction of polymerization for preheated stems. Stem preheating significantly increases transient temperatures at the bone/cement interface and also the risk of bone thermal necrosis, because the exposure time to high temperature is prolonged. The results provide interfacial characteristics for accurate modeling of bone cement polymerization to better understand the debonding process of cemented hip prostheses. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
Preparation of chitosan scaffolds with a hierarchical porous structure
Authors: Ko Young‐Gwang , Kawazoe Naoki , Tateishi Tetsuya , Chen Guoping 
Published: January 2010

AbstractDevelopment of porous scaffolds with open surface pore structures is required for tissue engineering to deliver cells into the three‐dimensional spaces in the scaffolds and improve cell distribution. This study demonstrated a new type of funnel‐like chitosan sponge prepared using ice particulates as a template. The funnel‐like chitosan sponges had a hierarchical bilayer porous structure of a surface layer and an interconnected bulk porous layer. The top surface porous layer consisted mainly of large open pores. The bulk porous layer was beneath the large surface pores and consisted of small pores that were connected with the large surface pores. The large surface pores were dependent on the shape, dimension, and density of the embossing ice particulates, while the bulk pores were dependent on the freezing temperature. The large open surface pores and interconnected bulk pores in the funnel‐like chitosan sponges facilitated cell seeding and cell distribution from the surface into the inner bulk pores. Cells cultured in the funnel‐like chitosan sponges showed high viability, high proliferation, and homogenous tissue formation. Such funnel‐like chitosan sponges will be useful for tissue engineering. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010
Retracted: Push‐out bond strengths of two fiber post types bonded with different dentin bonding agents
Authors: Topcu Fulya Toksoy , Erdemir Ugur , Sahinkesen Gunes , Mumcu Emre , Yildiz Esra , Uslan Ibrahim 
Published: January 2010

AbstractThe following article from Journal of Biomedical Materials Research Part B: Applied Biomaterials, “Push‐out bond strengths of two fiber post types bonded with different dentin bonding agents” by Fulya Toksoy Topcu, Ugur Erdemir, Gunes Sahinkesen, Emre Mumcu, Esra Yildiz, and Ibrahim Uslan, published online on January 20, 2010, in Wiley Online Library (www.wiley onlinelibrary.com <http://www.wiley onlinelibrary.com>), DOI: 10.1002/jbm.b.31590, and in Volume 93(2), pp. 359–366, has been retracted by agreement between the authors, the journal Editor‐in‐Chief, Jeremy L. Gilbert, and Wiley Periodicals, Inc.While the hypothesis, materials and methods, and results of this work have not been called into question, the paper contained unattributed overlap with Akgungor G, Akkayan B. Influence of dentin bonding agents and polymerization modes on the bond strength between translucent fiber posts and three dentin regions within a post space. J Prosthet Dent. 2006 May;95(5):368–378.This error was not identified by the authors prior to publication and does not have a direct impact on the merits of the experimental work described.