bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pathologic T1 clear cell renal cell carcinoma: Insulin‐like growth factor‐I receptor expression and disease‐specific survival
Authors: Parker Alexander S. , Cheville John C. , Blute Michael L. , Igel Todd , Lohse Christine M. , Cerhan James R. 
Published: May 2004

AbstractBACKGROUNDA proportion of patients diagnosed with pathologic T1 (pT1) clear cell renal cell carcinoma (CC‐RCC) will experience disease progression and death after surgery, whereas the majority remain disease free. The authors conducted a case–cohort investigation to examine the association of insulin‐like growth factor I receptor (IGF‐IR) expression and disease‐specific survival in patients who underwent surgery for pT1 CC‐RCC.METHODSEligible patients included those diagnosed with solitary, nonfamilial pT1 CC‐RCC who underwent radical nephrectomy at the Mayo Clinic‐Rochester between 1970 and 2000 (n = 886 patients). Among this group, 136 patients died of CC‐RCC (cases). Archived tumor blocks were not available for 62 patients, leaving a final study group of 74 cases. Stratified, random sampling was used to select a cohort of at least 3 year‐matched controls (no CC‐RCC death) for each case (n = 263 patients). Detection of IGF‐IR was performed using a commercially available monoclonal antibody. Cox proportional hazards models were fit to assess the association between IGF‐IR expression and disease‐specific survival.RESULTSAfter adjustment for age, the risk of death from CC‐RCC was greater for patients who had tumors that stained positive for IGF‐IR compared with patients who had tumors that showed no IGF‐IR expression (hazard ratio [HR], 1.5; 95% confidence interval, [95% CI], 0.9–2.4). In a stratified analysis, the risk was stronger among patients who had high‐grade tumors (HR, 2.2; 95% CI, 1.1–4.3) compared with patients who had low‐grade tumors (HR, 0.7; 95% CI, 0.3–1.5). Multivariate adjustment for tumor size and histologic tumor necrosis attenuated the association among all patients (HR, 1.3; 95% CI, 0.8–2.1) but strengthened the association among patients with high‐grade tumors (HR, 2.7; 95% CI, 1.3–5.6).CONCLUSIONSThe current data suggest that IGF‐IR expression is associated with poor survival in patients who are diagnosed with early‐stage CC‐RCC, especially among those with high‐grade disease. Cancer 2004. © 2004 American Cancer Society.
The cost‐effectiveness of aspirin versus cyclooxygenase‐2‐selective inhibitors for colorectal carcinoma chemoprevention in healthy individuals
Authors: Hur Chin , Simon Lee S. , Gazelle G. Scott 
Published: May 2004

AbstractBACKGROUNDAspirin therapy is accepted widely for secondary prevention in patients with documented cardiovascular disease, but there is a growing trend among healthy individuals to use aspirin as primary chemoprevention for both cardiovascular and oncologic diseases. Accruing evidence suggests that cyclooxygenase‐2‐selective inhibitors (coxibs) may be effective for colorectal carcinoma (CRC) chemoprevention but would not provide the primary cardiac benefit of aspirin.METHODSA computer‐based Markov model simulated hypothetical cohorts of healthy men age 50 years who took either 325 mg of enteric‐coated aspirin daily or celecoxib at a dose of 400 mg twice a day. Patients in both cohorts could develop drug‐related complications that would lead to its discontinuation. The aspirin group also was modeled to have a decreased rate of coronary ischemic events; however, decreased CRC mortality was not modeled in either group based on the assumption that the two treatments were effective equally in this regard. Data sources included published literature and the Centers for Medicare and Medicaid Services. Endpoints used to compare the two strategies included quality‐adjusted life years (QALYs), mortality and complication rates, and cost. The analysis was from a societal perspective with a time horizon of 10 years from age 50 years. Extensive sensitivity analyses were performed.RESULTSAspirin therapy resulted in 0.03 more QALYs and cost $23,000 less than coxib therapy over a 10‐year period. Compared with the aspirin group, the coxib group had 3.877% more complications and 0.17% more deaths. Alternatively stated, coxib therapy resulted in 1 patient complication or death for every 26 or 588 patients treated with coxibs, respectively.CONCLUSIONSAssuming equal efficacy in CRC prevention over a 10‐year period, aspirin was both more effective and less costly than coxib therapy when used for primary chemoprevention of CRC. Cancer 2004; © 2004 American Cancer Society.
HIV infection of primary human T cells is determined by tunable thresholds of T cell activation
Authors: Oswald‐Richter Kyra , Grill Stacy M. , Leelawong Mindy , Unutmaz Derya 
Published: May 2004

AbstractHIV infection of primary human T cells requires T cell activation signals. However, how strength, duration, and quality of TCR signals affect susceptibility of resting human T cells to HIV infection remains poorly understood. We found that the same threshold and duration of antigen signals that lead to optimal T cell activation are required for HIV to progress beyond the level of reversetranscription within resting T cells. Remarkably, sustained cytokine signaling from the IL‐2 receptor following TCR triggering was critical in establishing productive infection. While blockade of TCR signaling pathways with inhibitors of the phosphatidylinositol 3‐kinase pathway caused a partial pre‐integration block, another inhibitor, rapamycin, completely suppressed the infection. In contrast, cyclosporin A or FK506, inhibitors of NFAT, failed to block infection if the T cells were pre‐activated. Collectively, these results bring to light significant parallels between successful HIV infection and optimal thresholds of T cell activation. Furthermore, our results underscore the critical role of IL‐2 signaling in establishing productive HIV infection. These findings have important implications for our understanding of the complex interplay of HIV with host factors induced upon T cell activation.
GSTM1, GSTT1, and GSTP1 genotypes and the genotoxicity of hydroquinone in human lymphocytes
Authors: Silva Maria do Céu , Gaspar Jorge , Duarte Silva Isabel , Faber Ana , Rueff José 
Published: May 2004

AbstractHydroquinone is a myelotoxin that is found in many foods and is also formed through the metabolism of benzene. Human exposure to benzene is associated with the development of myelodysplastic syndrome and acute myelogenous leukemia. Hydroquinone is genotoxic in several in vitro and in vivo test systems, inducing micronuclei (MN), sister‐chromatid exchange (SCE), and chromosomal aberrations. Glutathione S‐transferases (GSTs) are a superfamily of polymorphic enzymes involved in the conjugation of reactive chemical intermediates to soluble forms. These enzymes play a key role in the detoxification of endogenous and exogenous compounds, and the polymorphic genes GSTM1, GSTT1, and GSTP1 have been associated with the differential metabolism of several genotoxicants. In the present study, we have evaluated the effect of GSTM1, GSTT1, and GSTP1 polymorphisms on the frequency of MN and SCE induced by hydroquinone in human lymphocytes. Lymphocytes were obtained from 15 healthy non‐smoking donors, and their GSTM1, GSTT1, and GSTP1 genotypes determined. Treatment of cultures of the lymphocytes with hydroquinone significantly increased the overall frequencies of MN and SCE (P<0.0001). Individuals with the GSTM1 null genotype had a significantly higher frequency of MN compared with GSTM1‐present individuals (P=0.013); in contrast, the GSTM1 genotype had no effect on hydroquinone‐induced SCE frequency. The other polymorphisms did not significantly affect the frequencies of MN or SCE. These results suggest that GSTM1 is involved in the metabolic fate of hydroquinone and that polymorphisms in GSTM1 could be related to inter‐individual differences in DNA damage arising from the exposure to this compound. Environ. Mol. Mutagen. 43:258–264, 2004. © 2004 Wiley‐Liss, Inc.
Bacterial and mammalian‐cell genotoxicity of mixtures of chlorohydroxyfuranones, by‐products of water chlorination
Authors: Mäki‐Paakkanen Jorma , Komulainen Hannu , Kronberg Leif 
Published: May 2004

AbstractThe genotoxic responses of mixtures of four chlorohydroxyfuranones (CHFs), 3‐chloro‐4‐(dichloromethyl)‐5‐hydroxy‐2(5H)‐furanone (MX), 3,4‐dichloro‐5‐hydroxy‐2(5H)‐furanone (MCA), 3‐chloro‐ 4‐(chloromethyl)‐5‐hydroxy‐2(5H)‐furanone (CMCF) and 3‐chloro‐4‐methyl‐5‐hydroxy‐2(5H)‐furanone (MCF), were compared with the genotoxicity of the individual compounds. Genotoxicity was evaluated in the Salmonella reversion assay (Ames test), the in vitro Chinese hamster ovary (CHO) cell Hprt mutation assay, and in the CHO chromosome aberration test. When tested individually, the concentrations of the chemicals that were chosen for the mixtures induced no or only a modest increase in the genotoxic effects, and caused little or no cytotoxicity. In the Ames test, the genotoxic responses caused by the mixtures of CHFs did not follow simple additivity. Synergism was observed with strains TA97 and TA98, and antagonism with strain TA100. In the CHO/Hprt mutation assay, the mutagenic response of the mixtures was inconsistent, with near additivity seen with a mixture of CHFs that resulted in 12% cell survival. In contrast, the four CHFs together consistently caused more structural chromosome damage (mainly chromatid‐type breaks and exchanges) compared to the sum of net effects of the four CHFs tested alone. Also, a potentiating effect was consistently seen for the cytotoxicity of the CHF mixtures both in the CHO/Hprt mutation assay and the chromosome aberration test. The present results indicate that the genotoxic effects of CHF mixtures can be greater than additive. Such effects may be worth considering in the cancer risk assessment of chlorinated drinking water. Environ. Mol. Mutagen. 43:217–225, 2004. © 2004 Wiley‐Liss, Inc.
Cytogenetic biomonitoring of Indian women cooking with biofuels: Micronucleus and chromosomal aberration tests in peripheral blood lymphocytes
Authors: Musthapa M. Syed , Lohani Mohtashim , Tiwari Smita , Mathur Neeraj , Prasad Rajendra , Rahman Qamar 
Published: May 2004

AbstractIndia currently has the largest number of indoor air pollution–related health problems in the world, with three‐quarters of its households burning wood, cowdung, or crop residues (“traditional” biomass fuels) for cooking, and the remainder using kerosene and relatively clean‐burning liquefied petroleum gas (LPG). Combustion of these fuels produces various pollutants that may cause serious health effects in exposed populations. In this study, the micronucleus (MN) and chromosomal aberration (CA) assays were used to evaluate the relative amounts of DNA damage produced by the use of these cooking fuels. Cytogenetic evaluation of 179 female subjects showed a significant increase in both MN and CA frequency in blood lymphocytes from users of biomass‐fuels in comparison to lymphocytes from LPG users (used as a reference population). The relative MN and CA frequencies for the users of the various fuels decreased in the order cowdung > cowdung/wood ≥ wood > kerosene ≥ LPG. Further, the results indicated an effect of subject age, and the duration of exposure on the MN and CA frequencies in biomass fuel users. Age had no significant effects on the genotoxicity responses in subjects with ≤10 years of exposure to either biomass fuels or LPG, but in subjects using biomass fuels for >10 years, CA and MN frequencies were higher in older individuals (>30 years of age) than younger subjects. Regardless of age, subjects burning biomass fuels had higher MN and CA frequencies than LPG users only when exposures were of at least 5 years duration. These results indicate that burning biomass‐based fuels increases the frequency of cytogenetic alterations in blood lymphocytes of exposed populations, possibly because of exposure to the various noxious gases and toxic substances present in biomass fuels. These cytogenetic markers could be used in the field to assess the genotoxic consequences of burning various cooking fuels and for early detection of genetic abnormalities in people exposed to various pollutants and toxicants. Environ. Mol. Mutagen. 43:243–249, 2004. © 2004 Wiley‐Liss, Inc.
Effect of deletion of SOS‐induced polymerases, pol II, IV, and V, on spontaneous mutagenesis in Escherichia coli mutD5
Authors: Nowosielska Anetta , Janion Celina , Grzesiuk Elzbieta 
Published: May 2004

AbstractThe E. coli dnaQ gene encodes the ϵ subunit of DNA polymerase III (pol III) responsible for the proofreading activity of this polymerase. The mutD5 mutant of dnaQ chronically expresses the SOS response and exhibits a mutator phenotype. In this study we have constructed a set of E. coli AB1157 mutD5 derivatives deleted in genes encoding SOS‐induced DNA polymerases, pol II, pol IV, and pol V, and estimated the frequency and specificity of spontaneous argE3→Arg+ reversion in exponentially growing and stationary‐phase cells of these strains. We found that pol II exerts a profound effect on the specificity of spontaneous mutation in exponentially growing cells. Analysis of growth‐dependent Arg+ revertants in mutD5 polB+ strains revealed that Arg+ revertants were due to tRNA suppressor formation, whereas those in mutD5 ΔpolB strains arose by back mutation at the argE3 ochre site. In stationary‐phase bacteria, Arg+revertants arose mainly by back mutation, regardless of whether they were proficient or deficient in pol II. Our results also indicate that in a mutD5 background, the absence of pol II led to increased frequency of Arg+ growth‐dependent revertants, whereas the lack of pol V caused its dramatic decrease, especially in mutD5 ΔumuDC and mutD5 ΔumuDC ΔpolB strains. In contrast, the rate of stationary‐phase Arg+revertants increased in the absence of pol IV in the mutD5 ΔdinB strain. We postulate that the proofreading activity of pol II excises DNA lesions in exponentially growing cells, whereas pol V and pol IV are more active in stationary‐phase cultures. Environ. Mol. Mutagen. 43:226–234, 2004. © 2004 Wiley‐Liss, Inc.
Hprt mutant frequencies in splenic T‐cells of male F344 rats exposed by inhalation to propylene
Authors: Walker Dale M. , Seilkop Steven K. , Scott Bobby R. , Walker Vernon E. 
Published: May 2004

AbstractPropylene is a major industrial intermediate and atmospheric pollutant to which humans are exposed by inhalation. In this study, 6‐week‐old male F344 rates were exposed to 0, 200, 2000, or 10,000 ppm propylene by inhalation for 4 weeks (6 h/day, 5 days/week), and mutant frequencies were determined in the Hprt gene of splenic T‐lymphocytes. Twenty milligrams of cyclophosphamide monohydrate (CPP)/kg bw, given on the penultimate day of propylene exposure, was used as a positive control mutagen. Rats (n = 8/group) were necropsied for isolation of T‐cells 8 weeks after the last dose, a sampling time that produced peak spleen Hprt mutant frequencies (Mfs) in a preliminary mutant manifestation study using CCP treatment. Hprt Mfs were measured via the T‐cell cloning assay, which was performed without knowledge of the animal treatment groups. Mean Hprt Mfs were significantly increased over control values (mean Mf = 5.24 ± 1.55 (SD) × 10−6) in CPP‐treated rats (10.37 ± 4.30 × 10−6, P = 0.007). However, Hprt Mfs in propylene‐exposed rats were not significantly increased over background, with mean Mfs of 4.90 ± 1.84 × 10−6 (P = 0.152), 5.05 ± 3.70 × 10−6 (P = 0.895), and 5.95 ± 2.49 ×10−6 (P = 0.500) for animals exposed to 200, 2000, or 10,000 ppm propylene, respectively. No significant increase in F344 rat or B6C3F1 mouse cancer incidence was reported in the National Toxicology Program carcinogenicity studies of propylene across this same exposure range. Taken together, these findings support the conclusion that inhalation exposure of rats to propylene does not cause mutations or cancer. Environ. Mol. Mutagen. 43:265–272, 2004. © 2004 Wiley‐Liss, Inc.
Use of RNA‐arbitrarily‐primed PCR to detect the induction of gene expression in freshwater bivalves (Unio tumidus) transplanted into the Moselle River
Authors: Rodius François , Hammer Claude , Vasseur Paule 
Published: May 2004

AbstractRNA‐arbitrarily‐primed PCR (RAP‐PCR) can be used to detect changes in gene expression in organisms for which only minimal genomic information is available. In this study, RAP‐PCR was used to detect modification of mRNA expression in the freshwater bivalve Unio tumidus, a mussel commonly used as a sentinel species in field studies. RNA expression was analyzed in the digestive glands of mussels from a control pond and in mussels transplanted into two sites on the Moselle River. The analysis identified a product in all animals exposed to sediments at the river station located downstream of a heavily populated area. This product was not present in animals exposed at the upstream station or at the control site. The additional PCR product was cloned and sequenced, and specific oligonucleotides for the sequence were designed to amplify cDNAs from control and transplanted mussels. A signal was obtained only with the cDNAs from animals exposed at the downstream station, confirming that the variation detected by RAP‐PCR corresponds to an increase of gene expression. Chemical analysis of sediments from the control and river sites indicated that the levels of several potential pollutants were similar at the three locations and below currently accepted pollution thresholds. Our results indicate that RAP‐PCR is a sensitive technique that can be applied in field studies to identify modifications in the gene expression of bioindicator species. This approach can complement chemical, biochemical and population studies to assess the impact of human activity on the ecological quality of aquatic systems. Environ. Mol. Mutagen. 43:209–216, 2004. © 2004 Wiley‐Liss, Inc.
DNA damage in peripheral blood lymphocytes of individuals residing near a wastewater drain and using underground water resources
Authors: Gandhi Gursatej , Kumar Naresh 
Published: May 2004

AbstractMahal is a linear village settlement situated about 0.5 km from an open waste‐water drain, the Tung Dhab drain, which carries effluents from local industrial sites. Villagers generally have a low‐to‐middle socio‐economic status and use ground water or a combination of ground water and tap water for drinking and for their other daily activities. The land in and around Mahal is used for agriculture and is irrigated by water from the Tung Dhab. The drain water contains heavy metals, and there is a possibility that these and other contaminants may reach the ground water table of Mahal and thereby compromise the health of the residents. The comet assay was performed on peripheral blood lymphocytes from Mahal villagers and revealed statistically significant increases in DNA damage as compared to a control group that does not use ground water. DNA damage was also significantly related to the age of the villagers and to the length of residence in the village. In the absence of other environmental exposures, it is concluded that the elevated DNA damage in the villagers is a consequence of continuous utilization of contaminated ground water. Environ. Mol. Mutagen. 43:235–242, 2004. © 2004 Wiley‐Liss, Inc.
Activity of topoisomerase inhibitors daunorubicin, idarubicin, and aclarubicin in the Drosophila Somatic Mutation and Recombination Test
Authors: Lehmann Mauricio , Vilar Knulp de Souza Prudente , Franco Aline , Reguly Maria Luíza , de Andrade Heloísa Helena Rodrigues 
Published: May 2004

AbstractAnthracyclines have been widely used as anticancer drugs against different types of human cancers. The present study evaluated the mutagenic and recombinagenic properties of two anthracycline topoisomerase II (topo II) poisons, daunorubicin (DNR) and idarubicin (IDA), as well as the related topo II catalytic inhibitor aclarubicin (ACLA), using the wing Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster. The three anthracyclines were positive in this bioassay, producing mainly mitotic homologous recombination. The results for spot‐size distribution and recombinagenic activity indicate that recombinational DNA damage accounts for ∼91, 86, and 62% of DNR, IDA, and ACLA genotoxicity, respectively. Besides being a catalytic inhibitor of topo II, ACLA is also a topoisomerase I (topo I) poison. This dual topo I and II inhibitory effect, associated with its DNA‐intercalating activity, could contribute to the activity of ACLA in the SMART assay. Environ. Mol. Mutagen. 43:250–257, 2004. © 2004 Wiley‐Liss, Inc.
Beitrag zum Vorkommen der Chromgelben Kratertrüffel – Pachyphloeus citrinusBerk. & Br. (Ascomycetes)
Authors: Hensel G. , Huth M. 
Published: May 2004

AbstractEs wird über das Vorkommen von Pachyphloeus citrinus in Deutschland und Europa berichtet. Ökologie und Phänologie werden diskutiert. Als Basis für eine weitere Bearbeitung werden die deutschen Funde zusammengestellt. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vier neue Arten aus den Gattungen Leucoagaricus und Leucocoprinus mit bräunlichen bis rußfarbigen Tönungen in den Hutfarben
Authors: Mohr P. , Ludwig E. 
Published: May 2004

AbstractVier neue Arten aus den Gattungen Leucoagaricus und Leucocoprinus werden beschrieben und gegen bekannte ähnliche Arten abgegrenzt. Leucoagaricus fuligineodiscus P.Mohr & E.Ludwig sp. nova stammt aus Brandenburg im östlichen Teil Deutschlands. Die anderen drei Arten, Leucoagaricus atroalbus P.Mohr & R.M.Dähncke sp. nova, L. brunneosquamulosus P.Mohr & R.M.Dähncke sp. nova und Leucocoprinus canariensis P.Mohr & R.M.Dähncke sp. nova, wurden auf La Palma, Kanarische Inseln (Spanien) gefunden. Leucocoprinus mauritianus (Henn.) P.Mohr wird neu kombiniert, Leucocoprinus heinemannii Migliozzi var. melanotrichoides P.Mohr neu aufgestellt. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hygrocybe rigelliae (Velen.) E.Ludwig comb. nov. und Hygrocybe roseascens sp. nova, eine nahestehende Art aus der Untergattung Cuphophyllus (Agaricales, Hygrophoraceae, Tricholomataceae)
Authors: Ludwig E. 
Published: May 2004

AbstractDie Literatur zu Hygrophorus rigelliae Velen. wird diskutiert, die Art wird zu Hygrocybe umkombiniert. Eine eng verwandte, neue Spezies – Hygrocybe roseascens – mit (nach Entwässerung) auffallenden rosa Tönen auf dem teilweise schuppigen Hut, 1–4‐sporigen Basidien und kleinen, (sub)globosen Sporen wird beschrieben. Die Unterschiede zu anderen Arten werden diskutiert. Eine Tafel mit Habituszeichnungen und den mikroskopischen Merkmalen wird beigegeben. Eine Farbtafel der neuen Art wird im Band III meines Pilzkompendiums veröffentlicht werden, steht aber bereits jetzt im Internet unter http://www.pabb‐web.de (“Pilzbilder”) zur Verfügung. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Bestimmungshilfen für einige europäische Rindenhelmlinge
Authors: Miersch J. , Hardtke H.‐J. , Rönsch P. 
Published: May 2004

AbstractDie Bestimmung von rindenbewohnenden Helmlingsarten (Mycena) ist schwierig. In publizierten Bestimmungsschlüsseln müssen zuerst die Sektionen und danach die Arten nach Mikromerkmalen erfasst werden. Um diese Schwierigkeiten zu überwinden, beschreiben wir für rindenbewohnende Helmlinge zwei Schlüssel, in denen mit Hilfe relativ einfacher Merkmale – wie Lamellenanheftung am Stiel, Hutfarben, Sporenform und Gestalt der Cheilozystiden, – 12 bis16 Arten erkannt werden können. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Periconiellaspecies occurring on ferns
Authors: Braun U. 
Published: May 2004

AbstractPericoniellaspecies occurring on ferns are discussed, described and illustrated.Periconiella lygodiisp. nova is validated, and the speciesP. benkertiisp. nova andP. rhachidicolasp. nova are introduced. A key is also provided to the species occurring on ferns. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)