bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation of Controllable Crystalline Nano-TiO2 by Homogeneous Hydrolysis
Authors: Liu Wei , Chen Ai-Ping , Lin Jia-Ping , Dai Zi-Ming , Qiu Wei , Liu Wei , Zhu Meng-Qin , Usuda Shouji 
Published: March 2004

Abstract
The crystal-form-controllable nanosize TiO2 was obtained using homogeneous hydrolysis method by the addition of toluene-p-sulfonic acid (TSA). Two processes of the rutile phase formation were proposed. The sample with 0.2 mole ratio of toluene-p-sulfonic acid was a mixed crystal of anatase and rutile, and characterised that the size of nano-crystalline was 19.5 nm for rutile, and 13.5 nm for anatase, the specific surface area was 72.7 m2/g, and the energy of band gap was 2.83 eV. The mechanism of development of rutile nanosize TiO2 was presented in homogeneous hydrolysis system with TSA.
Main Structural and Stereochemical Aspects of the Antiherpetic Activity of Nonahydroxyterphenoyl‐Containing C‐Glycosidic Ellagitannins
Authors: Quideau Stéphane , Varadinova Tatiana , Karagiozova Diana , Jourdes Michael , Pardon Patrick , Baudry Christian , Genova Petia , Diakov Theodore , Petrova Rozalina 
Published: March 2004

AbstractAntiherpetic evaluation of five nonahydroxyterphenoyl‐containing C‐glycosidic ellagitannins, castalagin (1), vescalagin (2), grandinin (3), roburin B (5), and roburin D (7), was performed in cultured cells against four HSV‐1 and HSV‐2 strains, two of which were resistant to Acyclovir. All five ellagitannins displayed significant anti‐HSV activities against the Acyclovir‐resistant mutants, but the monomeric structures 1–3 were more active than the dimers 5 and 7. Vescalagin (2) stands out among the five congeners tested as the most potent and selective inhibitor, with an IC50 value in the subfemtomolar range and a selectivity index 5×105 times higher than that of Acyclovir. Molecular modeling was used to provide a rationale for the surprisingly lower activity profile of its epimer castalagin (1). These ellagitannins have promising potential as novel inhibitors in the search for non‐nucleoside drugs active against Acyclovir‐resistant herpes viruses.
Two Pyrrolo[1,2‐a]azepine Type Alkaloids from Stemona collinsaeCraib: Structure Elucidations, Relationship to Asparagamine A, and a New Biogenetic Concept of Their Formation
Authors: Seger Christoph , Mereiter Kurt , Kaltenegger Elisabeth , Pacher Thomas , Greger Harald , Hofer Otmar 
Published: March 2004

AbstractThe alkaloids 1′,2′‐didehydrostemofoline (2) and 2′‐hydroxystemofoline (3) from Stemona collinsae Craib (Stemonaceae) were studied by X‐ray crystallography and NMR spectroscopy, and they are compared with the parent compound stemofoline (1). The X‐ray analysis of the CH2Cl2 solvate of 2′‐hydroxystemofoline (3) allowed the determination of the absolute configuration of this compound unequivocally, whereas optical rotation was used to infer the absolute configuration of 1′,2′‐didehydrostemofoline (2). Based on these results, it is shown that asparagamine A isolated from Asparagus racemosus Willd. (Asparagaceae) is identical to 1′,2′‐didehydrostemofoline obtained from S. collinsae Craib, and that the reported plant source of asparagamine A was most likely a Stemona species. In the context of the current investigations, a novel concept on the biosynthesis of Stemona alkaloids has been worked out and is presented here.
Complexity Analysis of Yeast Proteome Network
Authors: Bonchev Danail 
Published: March 2004

AbstractTopological and compositional complexity of proteinprotein networks is assessed in a variety of ways making use of graph theory and information theory. The methodology used is borrowed from mathematical chemistry and includes complexity descriptors such as substructure count, overall connectivity, walk count, and information on various vertex distributions. The approach is applied to the (incomplete) proteome of Saccharomyces cerevisiae containing 232 protein complexes of a total of 1,440 proteins. The proteome network and each of its nine functional subsets of protein complexes are disconnected graphs, containing a number of noninteracting species and a major component. A weighted edge between two vertices in these graphs stands for the number of shared proteins between the respective complexes. The major component is a highly connected, ‘small‐world’ network, in which the average vertex distance between protein complexes does not exceed 2.2 (2.4 for the entire proteome), whereas the maximum distance does not exceed 4 (or 5 for the proteome). The vertex degree distribution in the major proteome component with 199 complexes follows the power law P(k)∼k−γ, with γ≈1.7. The analysis of the functional organization of the yeast proteome has shown that, for any pair of biological functions, there always exist many proteins that can perform both functions. The potential application of the quantitative proteome descriptors discussed includes quantitative relationships between the structure and biological action of dynamic protein complexes in changing environment, identification of targets for markers/drugs, as well as system analysis and comparative studies of proteomes.
Synthesis and Biological Evaluation of PaclitaxelThiocolchicine Hybrids
Authors: Danieli Bruno , Giardini Alessandra , Lesma Giordano , Passarella Daniele , Silvani Alessandra , Appendino Giovanni , Noncovich Alain , Fontana Gabriele , Bombardelli Ezio , Sterner Olov 
Published: March 2004

AbstractThe bifunctional taxoidcolchicinoid hybrids 6–8 were synthesized and evaluated in assays of cytotoxicity and tubulin assembly/disassembly. All compounds showed a high degree of cytotoxicity, but, while 6 and 7 behaved as bifunctional tubulin binders not unlike an equimolecular mixture of taxol and thiocolchicine, 8 was surprisingly devoid of tubulin activity, acting on a distinct and yet to identify molecular target.
Neoadjuvant radiochemotherapy of oral cavity and oropharyngeal cancer: evaluation of tumor response by ct differs from histopathologic response assessment in a significant fraction of patients
Authors: Klug Clemens , Keszthelyi David , Ploder Oliver , Sulzbacher Irene , Voracek Martin , Wagner Arne , Millesi Werner , Kornek Gabriele , Kainberger Franz , Kermer Christian , Selzer Edgar 
Published: March 2004

AbstractBackground.Our aim was to compare and assess the predictive value of CT and histopathologic grading of tumor regression at primary tumor sites in patients with squamous cell carcinoma of the oral cavity and oropharynx after neoadjuvant (preoperative) radiochemotherapy (RCT).Methods.We investigated 55 patients with carcinomas of the oral cavity and oropharynx who underwent RCT before curative surgery. Two blinded observers measured RCT‐induced reduction of tumor volume in pretherapeutic and posttherapeutic CT scans. Volume changes were compared with histopathologic findings obtained at surgery.Results.Histopathologic response evaluation revealed 31 complete remissions, 12 cases of partial response, and 12 nonresponders. We performed a logistic regression analysis to evaluate whether measured volume reduction could predict the likelihood of belonging to a certain response group. Taken together, we found 35 correct, 12 false‐negative, and seven false‐positive predictions.Conclusions.The extent of remission as assessed by CT scans 4 to 5 weeks after completion of neoadjuvant RCT leads to false predictions in a significant percentage of patients. © 2004 Wiley Periodicals, Inc. Head Neck 26: 224–231, 2004
Impact of magnetic resonance imaging versus CT on nasopharyngeal carcinoma: primary tumor target delineation for radiotherapy
Authors: Chung Na‐Na , Ting Lai‐Lei , Hsu Wei‐Chung , Lui Louis Tak , Wang Po‐Ming 
Published: March 2004

AbstractBackground.Our aim was to assess the capacity of CT versus MRI for delineating to the primary tumor extent of nasopharyngeal carcinoma (NPC) in treated patients.Methods.From December 1997 to April 2000, 258 patients with NPC were enrolled. We focused on the primary tumor extension and the discrepancy between CT and MRI. The delineation of tumor invasion was crucial for determination of the gross tumor volume (GTV) before radiation therapy.Results.A total of 104 patients (40.3%) had intracranial infiltration detected by MRI, whereas CT showed negative findings (p = 6.879 × 10−11). Once the pterygopalatine fossa was involved, the chance of intracranial invasion was increased (96.1%). The detectable percentage of pterygopalatine fossa involvement accompanying intracranial invasion was higher with MRI than with CT (96.1% vs 56.9%).Conclusions.More detailed information about T and N classification of NPC was provided by MRI than by CT, which led to better target delineation for radiotherapy. © 2004 Wiley Periodicals, Inc. Head Neck 26: 241–246, 2004
Unnecessary laryngeal irradiation in the IMRT era
Authors: Amdur Robert J. , Li Jonathan G. , Liu Chihray , Hinerman Russell W. , Mendenhall William M. 
Published: March 2004

AbstractPurpose.The purpose of this review is to address the issue of unnecessary irradiation of the normal larynx.Methods.We performed a literature review and dosimetry evaluation of intensity modulated radiotheraphy (IMRT) techniques.Results.Data suggest that matching conventional parallel opposed photon fields through adenopathy is a reasonable alternative to the common practice of unnecessarily irradiating the normal larynx to high doses. The dosimetry evaluation demonstrates that the laryngeal dose is much higher when the entire neck is included in the IMRT field as opposed to using a standard anterior low‐neck field below the level of the thyroid notch.Conclusions.Lateral opposed fields should not be extended to include the larynx to avoid matching fields through adenopathy. IMRT fields should not include the normal larynx when the laryngeal dose would be substantially lower with a technique that shields the larynx in an anterior low‐neck field. © 2004 Wiley Periodicals, Inc. Head Neck 26: 257–264, 2004
Mutation analysis of the apoptotic “death‐receptors” and the adaptors TRADD and FADD/MORT‐1 in osteosarcoma tumor samples and osteosarcoma cell lines
Authors: Dechant Markus J. , Fellenberg Jörg , Scheuerpflug Christian G. , Ewerbeck Volker , Debatin Klaus‐Michael 
Published: March 2004

AbstractApoptosis is a key mechanism of the organism that regulates embryogenesis and development, maintains homeostasis of the immune system and removes potentially hazardous cells. A dysregulation of apoptosis signaling may thus disturb the balance of cell survival and cell death, leading to the development of several diseases including cancer. In order to determine whether osteosarcomas display an increased frequency of genetic alterations that affect apoptosis signaling, we analyzed the death domains of the death receptor genes CD95/Fas/Apo1, TNFR1, DR3/Apo3/WSL‐1/LARD/TRAMP, DR5/TRAIL‐R2/TRICK2/KILLER, DR6 and the complete coding sequences of the death receptor gene DR4/TRAIL‐R1 and the genes of the adaptors TRADD and FADD/MORT‐1. The investigation included 15 osteosarcoma tumor samples, 3 osteosarcoma cell lines (SAOS‐2, HOS and MG63) and peripheral blood from 20 donors as controls. We were able to identify 4 different sequence variations within the DR4 gene located on exons 3, 4, 5 and 10 (death‐domain). No alterations have been detected in the other genes or exons investigated. Except the sequence variant affecting exon 4, the alterations were homozygous in 15% of the tumor samples and cell lines, whereas the same alterations found in the control group were heterozygous or even not detectable. Three out of 4 alterations are located in the receptor's extracellular cysteine rich domain, which contains the ligand binding area and 1 on exon 10 coding for the death‐domain. They may thus exert influence on ligand‐receptor interactions and subsequent apoptosis induction. Our findings suggest that homozygous genetic alterations within the DR4 gene may be implicated in the formation of osteosarcoma. © 2004 Wiley‐Liss, Inc.
Aberrant methylation of trail decoy receptor genes is frequent in multiple tumor types
Authors: Shivapurkar Narayan , Toyooka Shinichi , Toyooka Kiyomi O. , Reddy Jyotsna , Miyajima Kuniharu , Suzuki Makoto , Shigematsu Hisayuki , Takahashi Takao , Parikh Gunjan , Pass Harvey I. , Chaudhary Preet M. , Gazdar Adi F. 
Published: March 2004

AbstractTNF‐related apoptosis‐inducing ligand (TRAIL) selectively induces programmed cell death (apoptosis) in various cancer cells but not in normal cells. TRAIL is known to bind to 4 different receptors, 2 proapoptotic (DR4 and DR5), and 2 potentially antiapoptotic receptors lacking death domains (DcR1 and DcR2). Aberrant promoter methylation and resultant silencing of tumor suppressor genes play an important role in the pathogenesis of many tumor types. Recently aberrant methylation of TRAIL decoy receptors was reported in pediatric tumor cell lines and neuroblastomas. We examined the methylation and expression status of TRAIL receptor genes in cancers of breast, lung, mesothelioma, prostate, bladder, cervix, ovary, brain and in hematopoietic malignancies. Aberrant methylation of DcR1 or DcR2 was present in 70% of primary breast cancers, 31% of primary lung cancers, in 63% of primary malignant mesothelioma (MM), in 60% of prostate cancer, in 42% of bladder cancer, in 100% of cervical cancer, in 43% of ovarian cancer, in 41% of lymphoma, in 26% of leukemia and in 56% of multiple myeloma. Methylation of DR4 and DR5 was rare in all the tumor types examined. Methylation of all the 4 receptors was rare in non malignant tissues. In cell lines, aberrant methylation of DcR1 was present in 11 of 23 (48%) breast, 10 of 27 (37%) lung and 3 of 7 (43%) MM, whereas aberrant methylation of DcR2 was present in 17 of 23 (74%) breast, 13 of 27 (48%) lung and 5 of 7 (71%) MM. The concordance between loss of gene expression and aberrant methylation ranged from 70–100%. Treatment with 5‐aza‐2′‐deoxycytidine restored DcR1 and DcR2 expression in 9 methylated cell lines confirming that aberrant methylation was the cause for silencing of DcR1 and DcR2 expression. Our results demonstrate that DcR1 and DcR2 genes are frequently methylated in various tumor types, and that the role of decoy receptors in tumor pathogenesis needs to be re‐evaluated. © 2004 Wiley‐Liss, Inc.
Prevalence of the Y165C, G382D and 1395delGGA germline mutations of the MYH gene in Italian patients with adenomatous polyposis coli and colorectal adenomas
Authors: Gismondi Viviana , Meta Maurizio , Bonelli Luigina , Radice Paolo , Sala Paola , Bertario Lucio , Viel Alessandra , Fornasarig Mara , Arrigoni Arrigo , Gentile Mattia , Ponz de Leon Maurizio , Anselmi Luca , Mareni Cristina , Bruzzi Paolo , Varesco Liliana 
Published: March 2004

AbstractBiallelic germline mutations in the base excision repair gene MYH have been reported in patients with multiple colorectal adenomas and cancer and in sporadic FAP patients not showing a detectable APC germline mutation. In this study, the prevalence of the common Y165C and G382D germline variants of the MYH gene was examined in 70 FAP/AAPC patients with no detectable APC mutation and a family history compatible with recessive inheritance. In addition, 141 normal‐population adenoma patients (mean number of adenomas, 2.8; range, 1–9) and 52 clean colon controls were studied. The entire coding region of the MYH gene was analyzed in Y165C or G382D heterozygous patients. Since the same second mutational event (a 3 bp deletion in exon 14, 1395delGGA) was detected in 3 patients, the prevalence of this variant was also examined in all groups. In all, 14 of 70 patients in the FAP/AAPC group (20%; 95% CI = 11.7–31.6%) had biallelic germline MYH variants and 3 were heterozygotes (4.3%). None of the 141 normal‐population adenoma patients carried biallelic germline MYH variants (95% CI = 0.06–4.1%) and 3 were heterozygotes (2.1%). In the control group, no MYH variants were detected. These results indicated that MYH‐associated polyposis (MAP) is present in about 20% of Italian FAP/AAPC patients, in whom no germline APC mutation is detectable and showing a family history compatible with recessive inheritance, and in a small fraction of patients with colorectal adenomas in the general population. In addition, our data suggest that mutation 1395delGGA is a subpolymorphic MYH mutational event in some Caucasian populations. © 2004 Wiley‐Liss, Inc.
Breast cancer cells induce osteoclast formation by stimulating host IL‐11 production and downregulating granulocyte/macrophage colony‐stimulating factor
Authors: Morgan Hayley , Tumber Anthony , Hill Peter A. 
Published: March 2004

AbstractBreast cancer cells frequently metastasize to the skeleton, where they induce OCL formation and activity, resulting in extensive bone destruction. However, the mechanisms by which breast cancer cells mediate increased osteolysis remain unclear. To elucidate this point, we investigated how 3 human breast cancer cell lines, MDA‐MB‐231, MDA‐MB‐435 and MCF‐7, induce OCL formation using a murine osteoblast–spleen cell coculture system and compared their effects with a human colorectal cancer cell line, HCT‐15; a human lung cancer cell line, HT‐1080; and a normal human breast cell line, HME. The breast cancer cell lines supported OCL formation only when osteoblasts were present in spleen cell cocultures, whilst the non‐breast cancer cell lines and the normal breast cell line, HME, had no effect. Fractionation of BCCM by ultrafiltration established that osteoclastogenic activity was associated with factors having m.w. >3 kDa. Breast cancer cell lines produced primarily PTHrP, with lesser amounts of IL‐6, IL‐11 and TNF‐α. The effect of BCCM on OCL formation in osteoblast–spleen cell cocultures was partially prevented by a neutralising antibody to human PTHrP and completely prevented by a neutralising antibody to either murine IL‐11 or the murine IL‐11 receptor; neutralising antibodies to human IL‐6, IL‐11 or TNF‐α were without effect. BCCM or human PTHrP induced an increase in murine osteoblast IL‐11 mRNA and protein production, effects that were prevented in the presence of a neutralising antibody to human PTHrP. The osteoclastogenic activity of IL‐11 was mediated by enhancing osteoblast production of PGE2 effects, which were abrogated by an inhibitor of cyclooxygenase. PGE2 apparently enhanced OCL formation by downregulating GM‐CSF production by spleen cells since recombinant murine GM‐CSF inhibited OCL formation and a neutralising antibody to murine GM‐CSF blocked these inhibitory effects. We conclude that breast cancer cells induce OCL formation by stimulating osteoblastic production of IL‐11. The subsequent release of PGE2 followed by inhibition of GM‐CSF production by cells within the bone microenvironment plays an important part in mediating the effects of breast cancer cells on OCL formation and their resorptive activity. © 2004 Wiley‐Liss, Inc.
Functional evaluation of collagen fiber scaffolds for ACL reconstruction: Cyclic loading in proteolytic enzyme solutions
Authors: Caruso Andrea B. , Dunn Michael G. 
Published: March 2004

AbstractThe mechanical properties of anterior cruciate ligament (ACL) reconstruction scaffolds were evaluated after exposure to functional challenges in vitro: cyclic loading combined with various proteolytic enzymes. Scaffolds were prepared from collagen fibers that were uncrosslinked (UNXL), crosslinked with ultraviolet irradiation (UV), or 1‐ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide (EDC; 10 or 25 mM). Structural properties of scaffolds were determined following 1‐h exposure to saline, trypsin, or bacterial collagenase, with and without simultaneous cyclic tensile loading (0 to 50 g; 0.5 Hz) in vitro. The breaking load and stiffness of UNXL and UV crosslinked scaffolds were significantly reduced by exposure to either trypsin or collagenase. Cyclic loads interacted synergistically with enzymes, rendering UNXL scaffolds untestable and further decreasing the breaking load of UV crosslinked scaffolds by approximately 35%. In contrast, the breaking load and stiffness of EDC crosslinked scaffolds, which were greater than those of UNXL or UV crosslinked scaffolds, were virtually unaffected by the same load and enzyme treatments. These results suggest that EDC is more effective than UV for crosslinking and stabilizing load‐bearing collagen fiber ACL reconstruction scaffolds. Application of cyclic loads and enzymes may lead to development of physiologically relevant in vitro test methods for load‐bearing scaffolds. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 69A: 164–171, 2004
Effect of enamel matrix proteins on the periodontal connective tissue‐material interface after wound healing
Authors: Craig R. G. , Kallur S. P. , Inoue M. , Rosenberg P. A. , LeGeros R. Z. 
Published: March 2004

AbstractThe periodontal ligament has the potential to regenerate a complete periodontal connective tissue attachment, starting with the deposition of cementum, on pathologically exposed root surfaces as well as several materials including titanium oxide. However, most commonly used dental materials result in a fibrous encapsulation or a chronic inflammatory response after periodontal wound healing rather than the formation of a periodontal connective tissue attachment. Recently, an extract of porcine enamel matrix (Emdogain®, EMD) has been reported inductive of cementum formation in both in vivo and in vitro studies. The aim of this study was to determine the effect of EMD, when applied to materials previously reported not supportive of periodontal connective tissue formation, on the periodontal connective tissue‐material interface obtained with these materials in vivo. Bilateral osteotomies were performed on the mandible of a Yucatan minipig exposing the buccal root surface of four premolars. A series of four preparations were placed in each root surface that were subsequently filled with calcium hydroxide, gutta percha, mineral trioxide aggregate (MTA), or left unfilled. One side, in addition, received an application of EMD prior to surgical closure. A bioabsorbable surgical barrier membrane was placed over the osteotomy sites to exclude gingival connective tissue from the wound‐healing environment. The mucoperiosteal flaps were then readapted and sutured in position. The animal was euthanized 10 weeks after the procedure, block sections obtained and prepared for light microscopy. Results demonstrated complete regeneration of alveolar bone and periodontal ligament in all four teeth from the EMD‐treated side. Fibers from the periodontal ligament were observed to insert into a mineralized matrix consistent with cementum on all four root preparations. In contrast, massive root resorption without regeneration of alveolar bone was found on all teeth from the side not treated with EMD. The results of this pilot study suggest that the application of EMD to material surfaces that normally do not support periodontal connective tissue attachment formation can alter the type of periodontal connective tissue interface obtained with these materials. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 69A: 180–187, 2004