bluuebunny/crossref_metadata_2025_split huggingface dataset:
Studies on mammary carcinogenesis induced by a heterocyclic amine, 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine, in mice and rats
Authors: Nagao Minako , Ushijima Toshikazu , Watanabe Naoko , Okochi Eriko , Ochiai Masako , Nakagama Hitoshi , Sugimura Takashi 
Published: August 2002

AbstractTen heterocyclic amines (HCAs) that are produced by heating amino acids, proteins, or proteinaceous food such as fish and meat were examined for carcinogenicity in rats and mice. Three of them, 2‐amino‐3‐methylimidazo[4,5‐f]quinoline (IQ), 2‐amino‐3,4‐dimethylimidazo[4,5‐f]quinoline (MeIQ), and 2‐amino‐1‐methyl‐6‐phenylimidazo[4,5‐b]pyridine (PhIP), have been shown to induce mammary cancer in female F344 and/or SD rats, but none of the HCAs induced mammary cancer in CDF1 mice. This report reviews our recent studies on mammary carcinogenesis of PhIP in various strains of mice and on the roles of genomic instability in the rat mammary carcinogenesis of PhIP. We demonstrated that the survival time from mammary adenocarcinomas was shorter in PhIP‐treated BALB/c mice than that in the untreated control, and with a significantly higher incidence in the C.B‐17 strain of mice compared with that of the control. To clarify mechanisms of mammary carcinogenesis, we examined genomic instability in rat mammary cancer induced by PhIP. Mammary cancers were induced in F344 × SD F1 rats harboring the lacI transgene, and two cell lines were established from two adenocarcinomas. They showed a greater than 10‐fold higher frequency of spontaneous mutations than that of the primary culture of normal mammary epithelial cells, in the lacI transgene and the hprt endogenous gene during cell replication. Nucleotide sequencing revealed that almost all types of mutations were increased, with a remarkable increase of A:T → C:G mutation. This genomic instability was not attributed either to alterations of mismatch‐repair enzymes or to p53. These mutational characteristics were also observed in the original tumors. Single‐nucleotide instability (SNI) might be implicated in the mammary cancer induced by PhIP. Environ. Mol. Mutagen. 39:158–164, 2002. © 2002 Wiley‐Liss, Inc.
Novel DNA repair alkyltransferase from Caenorhabditis elegans
Authors: Kanugula Sreenivas , Pegg Anthony E. 
Published: August 2002

AbstractO6‐Alkylguanine DNA‐alkyltransferase (AGT) is a widely distributed DNA repair protein that protects living organisms from endogenous and exogenous alkylation damage to DNA at the O6‐position of guanine. The search of the C. elegans genome database for an AGT protein revealed the presence of a protein (cAGT‐2) with some similarity to known AGTs in addition to the easily recognized cAGT‐1 protein. The predicted protein sequence of cAGT‐2 contains the amino acid sequence –ProCysHisPro– at the presumed active site of the protein, whereas all other known AGTs have –ProCysHisArg–. A truncated version of the cAGT‐2 protein was expressed in E. coli. This purified recombinant protein was able to repair O6‐methylguanine and O4‐methylthymine adducts in DNA in vitro and also reacted with the bulky benzyl adduct in O6‐benzylguanine. This fragment of cAGT‐2 (104 amino acids) is the smallest protein possessing AGT activity yet described. The full‐length cAGT‐2 protein (274 amino acids) totally lacks the N‐terminal domain present in all other known AGTs but has a long C‐terminal extension that has significant homology to histone 1C. Expression of cAGT‐2 in an E. coli strain lacking endogenous AGT activity provided modest but statistically significant resistance to the toxicity of N‐methyl‐N′‐nitro‐N‐nitrosoguanidine, confirming that cAGT‐2 is an alkyltransferase. Environ. Mol. Mutagen. 38:235–243, 2001. © 2001 Wiley‐Liss, Inc.
Constituents of the essential oil of cnidium officinale Makino, a Korean medicinal plant
Authors: Choi Hyang‐Sook , Kim Mie‐Soon Lee , Sawamura Masayoshi 
Published: August 2002

AbstractThe volatile flavour constituents of chunkung (Cnidium officinale Makino), isolated by simultaneous steam distillation–extraction, were investigated by capillary GC and GC–MS. Chunkung is a perennial plant of the Family Umbelliferae. This plant is characterized by its conspicuous oriental flavour and contains a copious amount of phthalides in the essential oil. Chunkung is one of the important folk medicines for counteracting a variety of diseases, and is particularly used as a traditional oriental medicine in the treatment of female genital inflammatory diseases. Sixty‐eight volatile flavour constituents, which make up 95.7% of the total volatile content of the oil, were detected in chunkung essential oil, which contained 25 hydrocarbons (15.9%), eight aldehydes (0.7%), 13 alcohols (11.5%), three ketones (0.5%), nine esters (1.4%), three oxides (0.4%), one acid (trace), five phthalides (64.8%) and one miscellaneous component (0.1%). cis‐Butylidene phthalide (33.2%) was the most abundant component followed by 3‐butyl phthalide (21.1%), cis‐3‐isobutylidene phthalide (10.1%) and terpinen‐4‐ol (8.5%). Copyright © 2001 John Wiley & Sons, Ltd.
Delivery risk and the hedging role of options
Authors: Lien Donald , Wong Kit Pong 
Published: August 2002

AbstractMultiple delivery specifications exist on nearly all commodity futures contracts. Sellers typically are
allowed to deliver any of several grades of the underlying commodity and at any of several locations. On the
delivery day, the futures price as such needs not converge to the spot price of the par‐delivery grade at
the par‐delivery location, thereby imposing an additional delivery risk on hedgers. This article derives
the optimal hedging strategy for a risk‐averse hedger in the presence of delivery risk. In particular, it
is shown that the hedger optimally uses options on futures for hedging purposes. This article provides a
rationale for the hedging role of options when futures markets allow for multiple delivery specifications.
© 2002 Wiley Periodicals, Inc. Jrl Fut Mark 22:339–354, 2002
t(1;3)(p36;p21) is a recurring therapy‐related translocation
Authors: Sato Yuko , Izumi Tohru , Kanamori Hirakazu , Davis Elizabeth M. , Miura Yasusada , Larson Richard A. , Le Beau Michelle M. , Ozawa Keiya , Rowley Janet D. 
Published: August 2002

AbstractChromosome bands 1p36 and 3p21 are known to be recurring breakpoints in therapy‐related (t‐) leukemia. We identified a recurring translocation, t(1;3)(p36;p21), in eight patients with various hematologic malignancies: three patients with ALL, one with chronic myelogenous leukemia (CML) in accelerated phase (AP), two with MDS, and two with AML(M3). Five of the eight patients had a history of chemotherapy, including alkylating agents in three, before the translocation was detected. In two of these five patients, the t(1;3)(p36;p21) emerged only at relapse or in the accelerated phase of CML. The karyotypes of the patients were complex, including −7 and structural abnormalities of 5q, 6q, 7q, 9p, and 11q23. Survival time varied among patients (25 days to more than 16 years). Using FISH with 13 1p35–36 cosmid probes (tel—FB12–CA5–G7–FD2–CB1–ED8–FD9–G32–AE3–G50–AD8–GG4–G43—cen), we delineated the 1p36 breakpoint in two patients with MDS and ALL as lying between FB12 and FD2 (between BAC47P3 and PAC963K15), with a small deletion near the breakpoint in both cases. In the patient with MDS, there was also a deletion at 3p21.3, as detected with the cosmid probe cosNRL9. The results of the present study suggest that t(1;3)(p36;p21) in hematologic diseases is associated with prior exposure to mutagens, including alkylating agents. © 2002 Wiley‐Liss, Inc.
Amplification of ribosomal RNA genes in acute myeloid leukemia
Authors: Fonatsch Christa , Nowotny Hadwiga , Pittermann‐Höcker Elisabeth , Streubel Berthold , Jäger Ulrich , Valent Peter , Büchner Thomas , Lechner Klaus 
Published: August 2002

AbstractGene amplification is a relatively rare event in acute myeloid leukemia (AML). Double minutes (dmin) and homogeneously staining regions are well established phenomena as cytogenetic correlates of gene amplification. Recently, however, two additional mechanisms leading to gene amplification, i.e., segmental jumping translocations and formation of ring chromosomes, have been described. We report four patients with AML, in whom bone marrow cells exhibited amplifications of ribosomal RNA (rRNA) genes in the form of ring chromosomes or a hsr. In two patients, the MLL gene, and in one patient the CBFA2 gene were shown to be co‐amplified with rRNA genes. In two of the four patients, multiple copies of alpha‐satellite sequences of the centromeres 13 and 21, respectively, were also demonstrated. In three of the four patients, the clinical course was very aggressive, leading to death within 2–8 months. In these three patients, complex karyotype abnormalities were found, whereas the karyotype of Patient 4 was characterized only by supernumerary ring 21 chromosomes of different sizes and a trisomy 8 in half of the metaphases. Modes of origin and clinical significance of the amplification of rRNA genes are discussed. © 2001 Wiley‐Liss, Inc.
Dbest1, a drosophila homolog of human bestrophin, is not required for viability or photoreceptor integrity
Authors: Tavsanli Beril C. , Pappu Kartik S. , Mehta Sunil Q. , Mardon Graeme 
Published: August 2002

AbstractSummary: Best macular dystrophy (BMD) is an autosomal dominant human disease characterized by macular degeneration with juvenile onset (OMIM 153700). The disease is most often associated with mutations in Bestrophin, which encodes a novel protein with four putative transmembrane domains. However, complete loss‐of‐function mutations in Bestrophin have not been reported in humans or mice. We have identified three homologs of human Bestrophin in the Drosophila genome (dbest1‐3). The protein products of these three genes share significant homology to a 364 amino acid N‐terminal domain of human Bestrophin. We used P‐element mutagenesis to delete dbest1, which encodes a protein with the highest amino acid similarity to Bestrophin. Three independent dbest1 mutants were recovered from the mutagenesis screen. Homozygous null mutations in dbest1 do not significantly alter the viability or fertility of mutant flies. Moreover, dbest1 mutants have normal photoreceptor morphology and function. genesis 31:130–136, 2001. © 2001 Wiley‐Liss, Inc.
Successful targeting of mouse Y chromosome genes using a site‐directed insertion vector
Authors: Rohozinski Jan , Agoulnik Alexander I. , Boettger‐Tong Holly L. , Bishop Colin E. 
Published: August 2002

AbstractSummary: Gene targeting via homologous recombination in mouse ES cells is now a routine method for addressing gene function in vivo. Several hundred genes mapping to all autosomes and the X chromosome have been mutated and analyzed in this way. In contrast, despite repeated attempts in several laboratories, including our own, there have been no reports of successful targeting of mouse Y chromosome genes. We show here that this problem can be overcome through the use of insertional targeting, rather than the usual replacement strategy. Using this method we have successfully targeted the mouse Y located Dby (dead box Y) and Eif2s3y (elongation initiation factor) genes. In addition, as Y chromosome genes are transcribed in ES cells, successful targeting and disruption of gene expression can be easily confirmed by RTPCR analysis of selected clones. genesis 32:1–7, 2002. © 2002 Wiley‐Liss, Inc.
An X‐linked GFP transgene reveals unexpected paternal X‐chromosome activity in trophoblastic giant cells of the mouse placenta
Authors: Hadjantonakis Anna‐Katerina , Cox Liza L. , Tam Patrick P.L. , Nagy Andras 
Published: August 2002

AbstractSummary: A GFP transgene has been integrated on the proximal part of the mouse X chromosome just distal of Timp and Syn1. During development, this X‐linked GFP transgene exhibits widespread green fluorescence throughout the embryonic and adult life of male mice but displays mosaic expression in tissues as a result of X‐inactivation in females. In living female embryos, inactivation of the transgene is imprinted in extraembryonic regions and random in the embryo proper, demonstrating that this reporter is behaving in a similar fashion to the majority of X‐linked loci, and so provides a vital readout of X chromosome activity. This is observation is further supported in T16H/X female mice harboring the GFP transgene on the normal X chromosome where reporter inactivation is observed in somatic cells. The differential expression of GFP activity facilitates fluorescence activated cell sorting for the purification of GFP+ vs. GFP‐ cells from female embryonic tissues, thereby allowing access to populations of cells that have kept active a particular X chromosome. By tracking the activity of this X‐linked GFP transgene, we discovered that the primary and secondary giant cells of the X/X placenta maintain an active paternal copy of this transgene on the presumed silenced paternal X‐chromosome. This finding implies that the imprint on the paternal X chromosome may be relaxed in these trophectodermal derivatives. genesis 29:133–140, 2001. © 2001 Wiley‐Liss, Inc.
The winged helix/forkhead transcription factor Foxq1 regulates differentiation of hair in satin mice
Authors: Hong Hee‐Kyung , Noveroske Janice K. , Headon Denis J. , Liu Tong , Sy Man‐Sun , Justice Monica J. , Chakravarti Aravinda 
Published: August 2002

AbstractSummary: Satin (sa) homozygous mice have a silky coat with high sheen arising from structurally abnormal medulla cells and defects in differentiation of the hair shaft. We demonstrate that the winged helix/forkhead transcription factor, Foxq1 (Forkhead box, subclass q, member 1) is mutant in sa mice. An intragenic deletion was identified in the radiation‐induced satin mutant of the SB/Le inbred strain; a second allele, identified by an N‐ethyl‐N‐nitrosourea (ENU) mutagenesis screen, has a missense mutation in the conserved winged helix DNA‐binding domain. Homozygous mutants of the two alleles are indistinguishable. We show that Foxq1 is expressed during embryogenesis and exhibits a tissue‐restricted expression pattern in adult tissues. The hair defects appear to be restricted to the inner structures of the hair; consequently, Foxq1 has a unique and distinct function involved in differentiation and development of the hair shaft. Despite an otherwise healthy appearance, satin mice have been reported to exhibit suppressed NK‐cell function and alloimmune cytotoxic T‐cell function. We show instead that the immune defects are attributable to genetic background differences. genesis 29:163–171, 2001. © 2001 Wiley‐Liss, Inc.
Trisialoganglioside GT1b induces in vivo degeneration of nigral dopaminergic neurons: Role of microglia
Authors: Ryu Jae K. , Shin Won H. , Kim Jean , Joe Eun H. , Lee Yong B. , Cho Kyung G. , Oh Young J. , Kim Seung U. , Jin Byung K. 
Published: August 2002

AbstractWe recently showed that trisialoganglioside (GT1b) induces cell death of dopaminergic neurons in rat mesencephalic cultures (Chung et al., Neuroreport 12:611–614, 2001). The present study examines the in vivo neurotoxic effects of GT1b on dopaminergic neurons in the substantia nigra (SN) of Sprague‐Dawley rats. Seven days after GT1b injection into the SN, immunocytochemical staining of SN tissue revealed death of nigral neurons, including dopaminergic neurons. Additional immunostaining using OX‐42 and OX‐6 antibodies showed that GT1b‐activated microglia were present in the SN where degeneration of nigral neurons was found. Western blot analysis and double‐labeled immunohistochemistry showed that inducible nitric oxide synthase (iNOS) was expressed in the SN, where its levels were maximal at 8 h post‐GT1b injection, and that iNOS was localized exclusively within microglia. GT1b‐induced loss of dopaminergic neurons in the SN was partially inhibited by NG‐nitro‐L‐arginine methyl ester hydrochloride, an NOS inhibitor. Our results indicate that in vivo neurotoxicity of GT1b against nigral dopaminergic neurons is at least in part mediated by nitric oxide released from activated microglia. Because GT1b exists abundantly in central nervous system neuronal membranes, our data support the hypothesis that immune‐mediated events triggered by endogenous compounds such as GT1b could contribute to the initiation and/or the progression of dopaminergic neuronal cell death that occurs in Parkinson's disease. GLIA 38:15–23, 2002. © 2002 Wiley‐Liss, Inc.
Developmental changes of tau protein and mRNA in cultured rat brain oligodendrocytes
Authors: Gorath Michaela , Stahnke Thomas , Mronga Thomas , Goldbaum Olaf , Richter‐Landsberg Christiane 
Published: August 2002

AbstractOligodendrocytes elaborate an extensive network of multibranched processes and flat membranous sheets. Microtubules (MT) participate in the elaboration and stabilization of myelin‐forming processes and are essential for cellular sorting processes. Microtubule‐associated proteins (MAPs) are involved in the regulation and stabilization of the dynamic MT network. It has been shown previously that oligodendrocytes express the MAP tau, a phosphoprotein most abundant in neurons of the CNS. In this article, we demonstrate for the first time that oligodendrocytes contain all six tau isoforms, and that tau mRNA and protein expression is developmentally regulated. Immunoblot analysis reveals that tau protein is more abundant, and mature isoforms are more prominent at later stages of development. During the first week of culture maturation, a marked decrease in phosphorylation is observable. Using an RT‐PCR approach, we can show that oligodendrocytes express small amounts of exon 3 containing isoforms and that during culture maturation, tau mRNA splice products with 3 MT‐binding domains (3R) decrease and mRNA with 4 MT‐binding domains (4R) increase. In situ hybridization study demonstrates that tau mRNA is present in precursor cells and in mature oligodendrocytes. Tau mRNA is actively transported into the cellular processes, is specifically present in the primary and some of the secondary processes, enriched at the turning and branching points and the growing tips, and often appears as small patches. Hence, localized tau translation at specific sites in the cellular extensions might contribute to the regulation of MT stability during process formation, early axonal contact establishment, and myelination. GLIA 36:89–101, 2001. © 2001 Wiley‐Liss, Inc.
Measuring the opinions of memory clinic users: patients, relatives and general practitioners
Authors: van Hout H. P. J. , Vernooij‐Dassen M. J. F. J. , Hoefnagels W. H. L. , Grol R. P. T. M. 
Published: August 2002

AbstractBackgroundThe opinions of memory clinic users are important to assess the value of memory clinics.ObjectiveTo measure the quality of care of an outpatient memory clinic for the elderly as perceived by patients, their relatives and general practitioners (GPs).MethodsAn observational study was conducted to measure the opinions of the users of a typical outpatient memory clinic. Opinions on five aspects were measured: (1) communication of the results, (2) provision of diagnostic information, (3) attitude of the clinicians, (4) usefulness of the medical assessment, and (5) information and advice to relatives. Patients and relatives were both interviewed with a dementia care satisfaction questionnaire. The GPs' opinions were derived with a self‐constructed questionnaire.ResultsOn 105 consecutive assessments, 101 opinions of GPs, 81 of caregivers and 31 of patients were recorded. Positive opinions were recorded on the way the results were communicated, the usefulness of the assessment and attitude of the clinicians. In contrast to GPs and relatives, patients were less positive about the clarity of the diagnostic information received. Both relatives and GPs were negative on information and advice to relatives.ConclusionsPatients, caregivers and GPs had positive opinions about the diagnostic value of the memory clinic. Quality improvement could focus on the clarity of the diagnostic information for patients and on better advice to relatives. Copyright © 2001 John Wiley & Sons, Ltd.
Influence of EEG electrodes on the BOLD fMRI signal
Authors: Bonmassar Giorgio , Hadjikhani Nouchine , Ives John R. , Hinton Denise , Belliveau John W. 
Published: August 2002

AbstractMeasurement of the EEG during fMRI scanning can give rise to image distortions due to magnetic susceptibility, eddy currents or chemical shift artifacts caused by certain types of EEG electrodes, cream, leads, or amplifiers. Two different creams were tested using MRS and T2* measurements, and we found that the one with higher water content was superior. This study introduces an index that quantifies the influence of EEG equipment on the BOLD fMRI signal. This index can also be used more generally to measure the changes in the fMRI signal due to the presence of any type of device inside (or outside) of the field of view (e.g., with fMRI and diffuse optical tomography, infrared imaging, transcranial magnetic stimulation, ultrasound imaging, etc.). Quantitative noise measurements are hampered by the normal variability of functional activation within the same subject and by the different slice profiles obtained when inserting a subject multiple times inside a MR imaging system. Our measurements account for these problems by using a matched filtering of cortical surface maps of functional activations. The results demonstrate that the BOLD signal is not influenced by the presence of EEG electrodes when using a properly constructed MRI compatible recording cap. Hum. Brain Mapping 14:108–115, 2001. © 2001 Wiley‐Liss, Inc.
An international survey of the use and effectiveness of modern manufacturing practices
Authors: Clegg C. W. , Wall T. D. , Pepper K. , Stride C. , Woods D. , Morrison D. , Cordery J. , Couchman P. , Badham R. , Kuenzler C. , Grote G. , Ide W. , Takahashi M. , Kogi K. 
Published: August 2002

AbstractWe describe a survey of the use and effectiveness of 12 manufacturing practices. The survey was administered to a random, stratified sample of companies with 150 or more employees in the United Kingdom, Australia, Japan, and Switzerland, yielding a total sample of 898 companies. We report findings on the extent of use of the practices, when they were introduced, their predicted future use, their effectiveness, and the correlates of their use and effectiveness. The data are examined for differences by country of location and country of ownership, as well as by industrial sector. © 2002 Wiley Periodicals, Inc.