bluuebunny/crossref_metadata_2025_split huggingface dataset:
Induction of c‐fos and c‐jun protooncogenes expression by formaldehyde‐releasing and epoxy resin‐based root‐canal sealers in human osteoblastic cells
Authors: Huang Fu‐Mei , Hsieh Yih‐Shou , Tai Kuo‐Wei , Chou Ming‐Yung , Chang Yu‐Chao 
Published: August 2002

AbstractAn important requirement for a root‐canal sealer is biologic compatibility; most evaluations have focused on general toxicological and local tissue irritating properties. There is only scant information about mutagenicity or carcinogenicity testing for root‐canal sealer. It has been shown that c‐fos and c‐jun are induced rapidly by a variety of chemical and physical stimuli. Numerous works have extensively investigated the induction mechanisms of c‐fos and c‐jun protooncogenes by these agents; however, little is known about the induction of cellular signaling events and specific gene expression after cell exposure to root‐canal sealers. Therefore, we used osteoblastic cell line U2‐OS to examine the effect of zinc‐oxide eugenol‐based (N2 and Endomethasome), epoxy resin‐based (AH Plus), and calcium hydroxide‐based (Sealapex) root‐canal sealers on the expression of c‐fos and c‐jun protooncogenes to understand in more detail the molecular mechanisms of root‐canal sealer‐induced genotoxicity. The cytotoxicity decreased in an order of N2 > Endomethasome > AH Plus > Sealapex. In addition, N2, Endomethasome, and AH Plus rapidly induced c‐jun and c‐fos mRNA levels in cells. However, Sealapex did not induce c‐jun and c‐fos mRNA expression at detectable levels all time points. Taken together, persistent induction of c‐jun and c‐fos protooncogenes by formaldehyde‐releasing and epoxy resin‐based root‐canal sealers may be distributed systemically via apex to cause some unexpected adverse effects on human beings. These data should be taken into consideration when choosing a root‐canal sealer. © 2001 Wiley Periodicals, Inc. J Biomed Mater Res 59: 460–465, 2002
Reactivity of plasma‐sprayed wollastonite coating in simulated body fluid
Authors: Liu Xuanyong , Ding Chuanxian 
Published: August 2002

AbstractWe incubated wollastonite coatings prepared with plasma spraying in simulated body fluids for different periods to investigate the reactivity. The surface structures of wollastonite coatings immersed in simulated body fluids were analyzed with scanning electron microscopy, Auger electron spectroscopy, and transmission electron microscopy. The results showed a carbonate‐containing hydroxyapatite layer formed on the surface of a plasma‐sprayed wollastonite coating soaked in simulated body fluids, and a silica‐rich layer appeared on the surface of the coating before the formation of the carbonate‐containing hydroxyapatite layer. The formation mechanism of apatite on the coating surface could be explained in terms of the ionic exchange between H+ within simulated body fluids and Ca2+ in the coating, which resulted in an increase in the ionic activity product of the apatite in simulated body fluids and provided a specific surface with a lower interface energy to the formation of apatite nuclei. © 2001 Wiley Periodicals, Inc. J Biomed Mater Res 59: 259–264, 2002
Mapping of an origin of DNA replication near the transcriptional promoter of the human HPRT gene
Authors: Cohen Stephanie M. , Brylawski Bruna P. , Cordeiro‐Stone Marila , Kaufman David G. 
Published: August 2002

AbstractA quantitative PCR method was used to map a functional origin of DNA replication in the hypoxanthine‐guanine phosphoribosyltransferase (HPRT) gene in normal human fibroblasts. This PCR method measures the abundance of specific sequences in short fragments of newly replicated DNA from logarithmically growing cells. Quantitative measurements rely on synthetic molecules (competitors) that amplify with the same primer sets as the target molecules, but generate products of different sizes. This method was first utilized to determine the position of the replication origin near the lamin B2 gene (Giacca et al. [1994] Proc. Natl. Acad. Sci. U S A. 91:7119–7123). In the present study, primer sets were tested along a 16‐kb region near exon 1 of the HPRT gene. The most abundant fragment was found to be located in the first intron of HPRT, just downstream of the promoter and exon 1 of the gene, and approximately 3.5 kb upstream of a previously reported autonomously replicating sequence (Sykes et al. [1988] Mol. Gen. Genet. 212:301–309). J. Cell. Biochem. 85: 346–356, 2002. © 2002 Wiley‐Liss, Inc.
Intruder state avoidance multireference Møller–Plesset perturbation theory
Authors: Witek Henryk A. , Choe Yoong‐Kee , Finley James P. , Hirao Kimihiko 
Published: August 2002

AbstractA new perturbation approach is proposed that enhances the low‐order, perturbative convergence by modifying the zeroth‐order Hamiltonian in a manner that enlarges any small‐energy denominators that may otherwise appear in the perturbative expansion. This intruder state avoidance (ISA) method can be used in conjunction with any perturbative approach, but is most applicable to cases where small energy denominators arise from orthogonal‐space states—so‐called intruder states—that should, under normal circumstances, make a negligible contribution to the target state of interests. This ISA method is used with multireference Møller–Plesset (MRMP) perturbation theory on potential energy curves that are otherwise plagued by singularities when treated with (conventional) MRMP; calculation are performed on the 13Σ state of O2; and the 21Δ, 31Δ, 23Δ, and 33Δ states of AgH. This approach is also applied to other calculations where MRMP is influenced by intruder states; calculations are performed on the 3Πu state of N2, the 3Π state of CO, and the 21A′ state of formamide. A number of calculations are also performed to illustrate that this approach has little or no effect on MRMP when intruder states are not present in perturbative calculations; vertical excitation energies are computed for the low‐lying states of N2, C2, CO, formamide, and benzene; the adiabatic 1A1–3B1 energy separation in CH2, and the spectroscopic parameters of O2 are also calculated. Vertical excitation energies are also performed on the Q and B bands states of free‐base, chlorin, and zinc–chlorin porphyrin, where somewhat larger couplings exists, and—as anticipated—a larger deviation is found between MRMP and ISA‐MRMP. © 2002 Wiley Periodicals, Inc. J Comput Chem 10: 957–965, 2002
One‐factorizations of complete graphs with vertex‐regular automorphism groups
Authors: Bonisoli Arrigo , Labbate Domenico 
Published: August 2002

AbstractWe consider one‐factorizations of K2n possessing an automorphism group acting regularly (sharply transitively) on vertices. We present some upper bounds on the number of one‐factors which are fixed by the group; further information is obtained when equality holds in these bounds. The case where the group is dihedral is studied in some detail, with some non‐existence statements in case the number of fixed one‐factors is as large as possible. Constructions both for dihedral groups and for some classes of abelian groups are given. © 2002 John Wiley & Sons, Inc. J Combin Designs 10: 1–16, 2002
Cripto: A tumor growth factor and more
Authors: Adamson Eileen D. , Minchiotti Gabriella , Salomon David S. 
Published: August 2002

AbstractCripto, a growth factor with an EGF‐like domain, and the first member of the EGF‐CFC family of genes to be sequenced and characterized, contributes to deregulated growth of cancer cells. A role for Cripto in tumor development has been described in the human and the mouse. Members of the EGF‐CFC family are found only in vertebrates: CFC proteins in zebrafish, Xenopus, chick, mouse and human have been characterized and indicate some common general functions in development. Cripto expression was first found in human and mouse embryonal carcinoma cells and male teratocarcinomas, and was demonstrated to be over‐expressed in breast, cervical, ovarian, gastric, lung, colon, and pancreatic carcinomas in contrast to normal tissues where Cripto expression was invariably low or absent. Cripto may play a role in mammary tumorigenesis, since in vitro, Cripto induces mammary cell proliferation, reduces apoptosis, increases cell migration, and inhibits milk protein expression. This prediction is strengthened by observations of Cripto expression in 80% of human and mouse mammary tumors. At least three important roles for Cripto in development have created considerable interest, and each activity may be distinct in its mechanism of receptor signaling. One role is in the patterning of the anterior–posterior axis of the early embryo, a second is a crucial role in the development of the heart, and a third is in potentiating branching morphogenesis and modulating differentiation in the developing mammary gland. Whether these properties are functions of different forms of Cripto, different Cripto receptors or the distinct domains within this 15–38 kDa glycoprotein are examined here, but much remains to be revealed about this evolutionarily conserved gene product. Since all Cripto receptors have not yet been determined with certainty, future possible uses as therapeutic targets remain to be developed. Cripto is released or shed from expressing cells and may serve as an accessible marker gene in the early to mid‐progressive stages of breast and other cancers. Meanwhile some speculations on possible receptor complexes for Cripto signaling in mammary cells are offered here as a spur to further discoveries. J. Cell. Physiol. 190: 267–278, 2002. © 2002 Wiley‐Liss, Inc.
Evidence that the death receptor DR4 is a DNA damage‐inducible, p53‐regulated gene
Authors: Guan Baoxiang , Yue Ping , Clayman Gary L. , Sun Shi‐Yong 
Published: August 2002

AbstractDR4 (TRAIL‐R1), a member of the tumor necrosis factor receptor superfamily, is a cell surface receptor that triggers the apoptotic machinery upon binding to its ligand tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL). Although three other TRAIL receptors DR5, DcR1, and DcR2 are induced by DNA damage and are regulated by the wild‐type p53 tumor suppressor, it was not known whether these factors also affect DR4 expression. In this study, we found that DR4 expression is also enhanced by DNA damage whether induced by ionizing radiation or by chemotherapeutic agents. The induction was observed predominantly in cells containing wild‐type p53 and was similar to the regulation patterns of DR5 and Fas, two other members of the family which are known to be regulated by p53. Transfection of HPV 16 E6 gene into cells with wild‐type p53, which decreased the level of p53 protein, resulted in suppression of DR4 induction by DNA‐damaging agents. Conversely, introduction of exogenous wild‐type p53 through adenovirus infection has led to upregulation of endogenous DR4 in cells with mutant p53. Moreover, the transcription inhibitor actinomycin D abolished DNA‐damaging agent‐induced DR4 expression. Thus, DR4 appears to be a DNA damage‐inducible, p53‐regulated gene. © 2001 Wiley‐Liss, Inc.
Alterations in fatty acid composition and fluidity of cell membranes affect the accumulation of PCB congener 2,2′,5,5′‐tetrachlorobiphenyl by Ralstonia eutropha H850
Authors: Kim In Seon , Beaudette Lee A , Cassidy Michael B , Lee Hung , Trevors Jack T 
Published: August 2002

AbstractThe effect of alterations in fatty acid composition and fluidity of cell membranes on the accumulation of PCB congener 2,2′,5,5′‐tetrachlorobiphenyl (TeCB) by Ralstonia eutropha (formerly Alcaligenes eutrophus) H850 was studied. Cells of R eutropha H850 grown on either biphenyl or fructose were used. Significant increases in saturated fatty acid composition and decreases in membrane fluidity of bacteria grown on biphenyl at 28 °C were observed compared with those grown on fructose at 17 or 28 °C. The ratio of saturated fatty acids to unsaturated fatty acids and membrane fluidity of R eutropha H850 grown on biphenyl at 28 °C resembled those of cells grown on fructose at 37 °C. No inhibition effect of the uncoupler 2,4‐dinitrophenol (2,4‐DNP) on TeCB accumulation was observed, suggesting an energy‐independent mechanism for TeCB accumulation in cells of R eutropha H850. The amount of TeCB accumulated was considerably higher in R eutropha H850 grown on fructose at 17 and 28 °C than when grown on biphenyl at 28 °C. Similar amounts of TeCB accumulated in bacteria grown on biphenyl at 28 °C as compared with those grown on fructose at 37 °C. These results suggest the alterations in fatty acid composition and membrane fluidity of R eutropha H850 may affect the accumulation of TeCB.© 2002 Society of Chemical Industry
Decomposition of formic acid in a photocatalytic reactor with a parallel array of four light sources
Authors: Wang Shinpon , Shiraishi Fumihide , Nakano Katsuyuki 
Published: August 2002

AbstractThe performance of a photocatalytic reactor system with a parallel array of four 6 W blacklight blue fluorescent lamps (wavelength: 300–400 nm) was investigated, based on the decomposition of formic acid in an aqueous solution. An aqueous solution of formic acid (7.8–22.0 gm−3) was recirculated between the photocatalytic reactor and perfectly‐mixed flow container. The results show that the UV‐light that penetrated through the wall of a glass tube and then passed through the flowing liquid solution accelerated the photocatalytic reaction occurring on the neighboring glass tubes, which greatly contributed to an increase in the reactor activity. This confirms that the arrangement of several light sources in parallel which uses effectively a three‐dimensional space can lead to increased reactor activity and an increase in decomposition rates. A significant reduction in the reaction rate due to a film‐diffusional resistance in the vicinity of the titanium dioxide film was observed.© 2002 Society of Chemical Industry
Sonographic appearance of lipoma of the inferior vena cava
Authors: Chou Yi‐Hong , Chiou Hong‐Jen , Tiu Chui‐Mei , Chiang Jen‐Huey , Chang Cheng‐Yen , Yu Chun 
Published: August 2002

AbstractLipomas of the major central veins are rare, and their sonographic features have rarely been reported. We report a case in which a lipoma of the inferior vena cava (IVC) was incidentally identified during liver sonography in a 68‐year‐old man. Sonography of the upper abdomen revealed coarsening of the liver echotexture, with a relatively small liver and atrophy of the right hepatic lobe. A 2‐cm hypoechoic hepatic nodule was visualized in segment IV. Sonography also showed a 2.2‐ × 1.8‐cm, highly echogenic, homogeneous nodule in the hepatic segment of the IVC at its junction with the right atrium. The lumen of the IVC was partially occluded. The CT and MRI appearances of the IVC lesion were consistent with a lipoma, which was not treated because there was no clinical evidence of obstruction. Histopathologic analysis following a sonographically guided biopsy of the liver nodule revealed hepatocellular carcinoma, which was treated by percutaneous ethanol injection. © 2001 John Wiley & Sons, Inc. J Clin Ultrasound 29:359–362, 2001.
Lymphatic function, lymphangiogenesis, and cancer metastasis
Authors: Swartz Melody A. , Skobe Mihaela 
Published: August 2002

AbstractThe lymphatic system serves as the primary route for the metastasis of many cancers and the extent of lymph node involvement is the most important indicator of tumor aggressiveness. Despite the apparent importance of the lymphatic vessels for tumor dissemination, it has remained unclear whether activation of lymphatic endothelial cells may affect tumor progression and metastasis and the molecular mechanisms of lymphangiogenesis are just beginning to be elucidated. This overview describes the unique structural and functional characteristics of the lymphatic vessels that render them particularly suitable for invasion by tumor cells and for their efficient transport to lymph nodes. Recent evidence indicates occurrence of tumor lymphangiogenesis and its correlation with metastasis. Molecular regulation of tumor lymphangiogenesis, its significance for tumor metastasis, and implications for cancer therapy are discussed. Microsc. Res. Tech. 55:92–99, 2001. © 2001 Wiley‐Liss, Inc.
Microscopic overview of crinoid regeneration
Authors: Candia Carnevali M. Daniela , Bonasoro Francesco 
Published: August 2002

AbstractCrinoids are well known for their striking regenerative potential and can rapidly and completely regenerate arms lost following self‐induced or traumatic amputation. Thus they provide a valuable experimental model for investigation of the regenerative process from the macroscopic to the molecular level. In these last years we have studied in detail the overall process of arm regeneration in the comatulid Antedon mediterranea. This phenomenon can be described on the whole as a typical blastemal regeneration in which new structures develop from migratory pluripotential, actively proliferating cells in the presence of presumptive regulatory factors. The overall process can be subdivided into three main phases: a repair phase, an early regenerative phase, and an advanced regenerative phase, whose crucial aspects are related to common fundamental mechanisms such as cell migration and proliferation, intervention of stem cells and/or dedifferentiated cells, contribution of putative growth factors, particularly in terms of specific neurally derived factors, and mechanisms of pattern formation. This article focuses on the main aspects of the phenomenon and gives a brief account of the most recent and relevant results. Our approach employs classical methods of light (LM) and electron (TEM and SEM) microscopy, immunocytochemistry, and histofluorescence on experimentally induced arm regenerations of standard or abnormal type obtained in significantly different experimental conditions, including extreme mutilations (explants) or exposure to pseudo‐estrogenic environmental contamination. Microsc. Res. Tech. 55:403–426, 2001. © 2001 Wiley‐Liss, Inc.
Genomic analysis of Hox clusters in the sea lamprey Petromyzon marinus
Authors: Irvine Steven Q. , Carr Janet L. , Bailey Wendy J. , Kawasaki Kazuhiko , Shimizu Nobuyoshi , Amemiya Chris T. , Ruddle Frank H. 
Published: August 2002

AbstractThe sea lamprey Petromyzon marinus is among the most primitive of extant vertebrates. We are interested in the organization of its Hox gene clusters, because, as a close relative of the gnathostomes, this information would help to infer Hox cluster organization at the base of the gnathostome radiation. We have partially mapped the P. marinus Hox clusters using phage, cosmid, and P1 artificial chromosome libraries. Complete homeobox sequences were obtained for the 22 Hox genes recovered in the genomic library screens and analyzed for cognate group identity. We estimate that the clusters are somewhat larger than those of mammals (roughly 140 kbp vs. 105 kbp) but much smaller than the single Hox cluster of the cephalochordate amphioxus (at more than 260 kb). We never obtained more than three genes from any single cognate group from the genomic library screens, although it is unlikely that our screen was exhaustive, and therefore conclude that P. marinus has a total of either three or four Hox clusters. We also identify four highly conserved non‐coding sequence motifs shared with higher vertebrates in a genomic comparison of Hox 10 genes. J. Exp. Zool. (Mol. Dev. Evol.) 294:47–62, 2002. © 2002 Wiley‐Liss, Inc.
Hox cluster organization in the jawless vertebrate Petromyzon marinus
Authors: Force Allan , Amores Angel , Postlethwait John H. 
Published: August 2002

AbstractLarge‐scale gene amplifications may have facilitated the evolution of morphological innovations that accompanied the origin of vertebrates. This hypothesis predicts that the genomes of extant jawless fish, scions of deeply branching vertebrate lineages, should bear a record of these events. Previous work suggests that nonvertebrate chordates have a single Hox cluster, but that gnathostome vertebrates have four or more Hox clusters. Did the duplication events that produced multiple vertebrate Hox clusters occur before or after the divergence of agnathan and gnathostome lineages? Can investigation of lamprey Hox clusters illuminate the origins of the four gnathostome Hox clusters? To approach these questions, we cloned and sequenced 13 Hox cluster genes from cDNA and genomic libraries in the lamprey, Petromyzon marinus. The results suggest that the lamprey has at least four Hox clusters and support the model that gnathostome Hox clusters arose by a two‐round‐no‐cluster‐loss mechanism, with tree topology [(AB)(CD)]. A three‐round model, however, is not rigorously excluded by the data and, for this model, the tree topologies [(D(C(AB))] and [(C(D(AB))] are most parsimonious. Gene phylogenies suggest that at least one Hox cluster duplication occurred in the lamprey lineage after it diverged from the gnathostome lineage. The results argue against two or more rounds of duplication before the divergence of agnathan and gnathostome vertebrates. If Hox clusters were duplicated in whole‐genome duplication events, then these data suggest that, at most, one whole genome duplication occurred before the evolution of vertebrate developmental innovations. J. Exp. Zool. (Mol. Dev. Evol.) 294:30–46, 2002. © 2002 Wiley‐Liss, Inc.
Inbreeding in Littledale's whistling rat Parotomys littledalei
Authors: Pillay Neville 
Published: August 2002

AbstractDespite its rarity in nature, inbreeding is sometimes evident in species occupying ephemeral, unpredictable habitats, and which occur at low densities. One such species is Littledale's whistling rat, Parotomys littledalei, a murid rodent endemic to the south‐west arid region of South Africa. Using a captive population of P. littledalei, I studied mate choice for kin and nonkin, and the reproductive performance of inbred and outbred pairs. In choice tests, estrous females presented with either odors or actual males showed a preference for siblings or half‐siblings to unrelated males. Males did not discriminate between the odor of estrous kin and nonkin. In breeding studies, inbred (mother‐son; brother‐sister) and outbred (proven female and an unrelated young male and nonsiblings) pairs had a similar reproductive output, although the sex ratio favored males in inbred litters. The development of inbred young was indistinguishable from outbred young. The results indicate that female P. littledalei prefer to inbreed, but there are no apparent advantages to inbreeding over outbreeding. © 2002 Wiley‐Liss, Inc.
Expression of muscle‐specific myosin heavy chain and myosin light chain 1 in the electric tissue of Electrophorus electricus (L.) in comparison with other vertebrate species
Authors: Ayres Sá Lilian , Menezes Meiga Aurea , dos Santos Mermelstein Claudia 
Published: August 2002

AbstractMyosin light and heavy chains from skeletal and cardiac muscles and from the electric organ of Electrophorus electricus (L.) were characterised using biochemical and immunological methods, and compared with myosin extracted from avian, reptilian, and mammalian skeletal and cardiac muscles. The results indicate that the electric tissue has a myosin light chain 1 (LC1) and a muscle‐specific myosin heavy chain. We also show that monoclonal antibody F109‐12A8 (against LC1 and LC2) recognizes LC1 of myosin from human skeletal and cardiac muscles as well as those of rabbit, lizard, chick, and electric eel. However, only cardiac muscles from humans and rabbits have LC2, which is recognized by antibody F109‐16F4. The data presented confirm the muscle origin of the electric tissue of E. electricus. This electric tissue has a profile of LC1 protein expression that resembles the myosin from cardiac muscle of the eel more than that from eel skeletal muscle. This work raises an interesting question about the ontogenesis and differentiation of the electric tissue of E. electricus. J. Exp. Zool. 290:227–233, 2001. © 2001 Wiley‐Liss, Inc.