bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bladder Tumor Contains Higher N7-Methylguanine Levels in DNA than Adjacent Normal Bladder Epithelium
Authors: Saad Abir A. , O'Connor Peter J. , Mostafa Mostafa H. , Metwalli Nabila E. , Cooper Donald P. , Margison Geoffrey P. , Povey Andrew C. 
Published: April 2006

Abstract
Schistosoma haematobium–infected patients are more likely to develop bladder cancer and be more exposed to carcinogenic N-nitroso compounds than uninfected patients. As N7-methylguanine is a marker of exposure to methylating agents of this type, we have measured N7-methyldeoxyguanosine 3′-monophosphate (N7-MedGp) by 32P postlabeling. DNA was isolated from 42 paired normal and tumor tissue of Egyptians with bladder cancer. N7-MedGp was detected in DNA from 93% of the tumors and 74% of the normal bladder tissue samples. Adduct levels were highly variable and ranged from 0.04 to 6.4 and from 0.02 to 0.72 μmol/mol deoxyguanosine 3′-monophosphate (dGp) in tumor and normal DNA, respectively. N7-MedGp levels in normal and tumor DNA were highly correlated with one another (P = 0.007). The mean difference (95% confidence interval) in adduct levels between tumor and normal DNA was 0.21 (0.13-0.32) μmol/mol dGp and this was statistically significant (P &lt; 0.001). The adduct ratio (tumor DNA/normal DNA) varied between 0.2 and 136 (median, 4.6). N7-MedGp levels were not associated with gender, age, or the presence of schistosomiasis. However, lower N7-MedGp levels were found in normal DNA from individuals lacking the GSTM1 gene (P = 0.03) but not the GSTT1 gene or in subjects with the Ile105Val GSTP1 polymorphism. These results show that exposure to methylating agents is widespread and suggest that such exposure may play a role both in tumor initiation and progression. (Cancer Epidemiol Biomarkers Prev 2006;15(4):740–3)
Polymorphisms in Polycyclic Aromatic Hydrocarbon Metabolism and Conjugation Genes, Interactions with Smoking and Prostate Cancer Risk
Authors: Nock Nora L. , Liu Xin , Cicek Mine S. , Li Li , Macarie Flavius , Rybicki Benjamin A. , Plummer Sarah J. , MacLennan Gregory T. , Casey Graham , Witte John S. 
Published: April 2006

AbstractThe relationship between cigarette smoking and prostate cancer remains unclear. Any potential association may depend on the individuals' ability to metabolize and detoxify cigarette carcinogens—such as polycyclic aromatic hydrocarbons. To investigate this, we studied the association between prostate cancer and smoking, as well as the main and modifying effects of functional polymorphisms in genes that metabolize polycyclic aromatic hydrocarbons (CYP1A1 Ile462Val, microsomal epoxide hydrolase His139Arg) and detoxify reactive derivatives (GSTM1 null deletion, GSTT1 null deletion, GSTP1 Ile105Val and Ala114Val) using a family-based case-control design (439 prostate cancer cases and 479 brother controls). Within the entire study population, there were no main effects for smoking or any of the polymorphisms. However, the nondeleted GSTM1 allele was inversely associated with prostate cancer [odds ratio (OR), 0.50; 95% confidence interval (95% CI), 0.26-0.94] among men with less aggressive disease (Gleason score &lt; 7 and clinical tumor stage &lt; T2c) and positively associated (OR, 1.68; 95% CI, 1.01-2.79) with prostate cancer in men with more aggressive disease (Gleason score ≥ 7 or clinical tumor stage ≥ T2c). We also found a statistically significant negative multiplicative interaction between the GSTM1 nondeleted allele and heavy smoking (&gt; 20 pack-years) in the total study population (P = 0.01) and in Caucasians (P = 0.01). Among Caucasians, heavy smoking increased prostate cancer risk nearly 2-fold in those with the GSTM1 null genotype (OR, 1.73; 95% CI, 0.99-3.05) but this increased risk was not observed in heavy smokers who carried the GSTM1 nondeleted allele (OR, 0.95; 95% CI, 0.53-1.71). Our results highlight the importance of considering genetic modifiers of carcinogens when evaluating smoking in prostate cancer. (Cancer Epidemiol Biomarkers Prev 2006;15(4):765–61)
The Effect of Medicare Health Care Delivery Systems on Survival for Patients with Breast and Colorectal Cancer
Authors: Kirsner Robert S. , Ma Fangchao , Fleming Lora , Federman Daniel G. , Trapido Edward , Duncan Robert , Wilkinson James D. 
Published: April 2006

AbstractBackground: Two of the most common types of health care delivery systems in the U.S. are fee-for-service (FFS) and managed care systems such as health maintenance organizations (HMO). Differences may exist in patient outcomes depending on the health care delivery system in which they are enrolled. We evaluated differences in the survival of patients with breast and colorectal cancer at diagnosis between the two Medicare health care delivery systems (FFS and HMO).Methods: We used a linkage of two national databases, the Medicare database from the Centers for Medicare and Medicaid Services, and the National Cancer Institute's Surveillance, Epidemiology, and End Results program database, to evaluate differences in demographic data, stage at diagnosis, and survival between breast and colorectal cancer over the period 1985 to 2001.Results: Medicare patients enrolled in HMOs were diagnosed at an earlier stage of diagnosis than FFS patients. HMO patients diagnosed with breast and colorectal cancer had improved survival, and these differences remained even after controlling for potential confounders (such as stage at diagnosis, age, race, socioeconomic status, and marital status). Specifically, patients enrolled in HMOs had 9% greater survival in hazards ratio if they had breast cancer, and 6% if they had colorectal cancer.Conclusions: Differences exist in survival among patients in HMOs compared with FFS. This is likely due to a combination of factors, including but not limited to, earlier stage at the time of diagnoses. (Cancer Epidemiol Biomarkers Prev 2006;15(4):769–73)
Emerging and Widening Colorectal Carcinoma Disparities Between Blacks and Whites in the United States (1975-2002)
Authors: Irby Kimberly , Anderson William F. , Henson Donald E. , Devesa Susan S. 
Published: April 2006

AbstractBackground: Colorectal carcinoma (CRC) is the fourth most common cancer diagnosed and the second most common cause of cancer death in the U.S. Incidence and mortality rates have decreased since the mid-1980s, although more among Whites than Blacks.Methods: To determine if these racial differences were changing over time, we examined CRC rates in the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program (1975-2002). Rates were stratified by gender, race, anatomic subsite, historic stage, and grade.Results: CRC rates were higher among men than women and higher among Blacks than Whites, with Black men having the highest rates during the latter years. Prior to the mid-1980s, male CRC rates were actually higher among Whites than Blacks; after which there was ethnic crossover with Black rates higher than White rates, and the gaps are widening. Proximal and transverse CRCs were more common and rectal cancers were less common among Blacks than Whites. Over time, rates for localized and regional stages increased among Blacks and decreased among Whites. Rates for distant stages declined for both racial groups, although less among Blacks. Black-to-White rate ratio for distant stage was ∼1.30. Notably, Blacks compared with Whites had lower grade tumors, despite higher stages and mortality rates.Conclusions: CRC racial disparities have emerged and widened for three decades. These temporal trends probably reflect complicated racial differences between screening practice patterns and etiologic factors. (Cancer Epidemiol Biomarkers Prev 2006;15(4):792–7)
Smoking and Overweight: Negative Prognostic Factors in Stage III Epithelial Ovarian Cancer
Authors: Kjærbye-Thygesen Anette , Frederiksen Kirsten , Høgdall Estrid V. , Glud Eva , Christensen Lise , Høgdall Claus K. , Blaakær Jan , Kjær Susanne K. 
Published: April 2006

Abstract
Objective: Smoking and overweight are associated with poorer prognosis in several cancer types. The prognostic effect of smoking and body mass index (BMI) on ovarian cancer is unknown.
Methods: Ovarian cancer cases were from the Danish MALOVA (MALignant OVArian cancer) study. Information on smoking status and BMI was obtained from a personal interview conducted closely after primary surgery. Cox regression models were used to estimate adjusted hazard ratios (HR) and 95% confidence intervals (95% CI) for ovarian cancer–specific death in relation to smoking variables and BMI.
Results: A total of 295 women with stage III epithelial ovarian cancer were identified and followed to death or for a median of 7.3 years (range, 5.4-9.5 years). Median survival time for normal-weight never smokers was 2.8 years (95% CI, 2.3-3.2) compared with 1.2 years (95% CI, 0.8-2.3) for overweight current smokers. Current smokers had a significantly increased risk of ovarian cancer death compared with never smokers in multivariate Cox analysis (HR, 1.65; 95% CI, 1.22-2.24). The negative effect of smoking diminished with increasing time since a former smoker had stopped smoking (HR, 0.89; 95% CI, 0.80-0.98 per 5 years since stop of smoking). Overweight women also had an increased risk of ovarian cancer death (HR, 1.83; 95% CI, 1.38-2.42) compared with normal-weight women.
Conclusion: Smoking at the time of diagnosis and premorbid overweight were negative prognostic factors for ovarian cancer–specific survival. The negative effect of smoking decreased with increasing time since stop of smoking. (Cancer Epidemiol Biomarkers Prev 2006;15(4):798–803)
Effects of Chemical Form of Selenium on Plasma Biomarkers in a High-Dose Human Supplementation Trial
Authors: Burk Raymond F. , Norsworthy Brooke K. , Hill Kristina E. , Motley Amy K. , Byrne Daniel W. 
Published: April 2006

Abstract
Intervention trials with different forms of selenium are under way to assess the effects of selenium supplements on the incidence of cancer and other diseases. Plasma selenium biomarkers respond to selenium administration and might be useful for assessing compliance and safety in these trials. The present study characterized the effects of selenium supplementation on plasma selenium biomarkers and urinary selenium excretion in selenium-replete subjects. Moderate (∼200 μg/d) to large (∼600 μg/d) selenium supplements in the forms sodium selenite, high-selenium yeast (yeast), and l-selenomethionine (selenomethionine) were administered. Subjects were randomized into 10 groups (placebo and three dose levels of each form of selenium). Plasma biomarkers (selenium concentration, selenoprotein P concentration, and glutathione peroxidase activity) were determined before supplementation and every 4 weeks for 16 weeks. Urinary selenium excretion was determined at 16 weeks. Supplementation with selenomethionine and yeast raised the plasma selenium concentration in a dose-dependent manner. Selenite did not. The increased selenium concentration correlated with the amount of selenomethionine administered. Neither glutathione peroxidase activity nor selenoprotein P concentration responded to selenium supplementation. Urinary selenium excretion was greater after selenomethionine than after selenite, with excretion after yeast being intermediate and not significantly different from either of the other two. We conclude that plasma selenium concentration is useful in monitoring compliance and safety of selenium supplementation as selenomethionine but not as selenite. Plasma selenium seems to reflect the selenomethionine content of yeast but not the other yeast selenium forms. As judged by urinary selenium excretion, selenium in the form of selenomethionine is better absorbed than selenite. (Cancer Epidemiol Biomarkers Prev 2006;15(4):804–10)
Static pressure–volume curves and body posture in severe chronic bronchitis
Authors: Mentzelopoulos S. D. , Sigala J. , Roussos C. , Zakynthinos S. G. 
Published: April 2006

Based on prior data, the current authors hypothesised that beneficial pronation effects on gas exchange and respiratory mechanics might be maximised in severely hyperinflated chronic bronchitis patients. The current authors also sought to elucidate underlying mechanisms and to determine whether pronation effects are reflected by postural changes in inspiratory pressure–volume (P–V) curve characteristics.A total of 16 mechanically ventilated patients (for 16–36 h) with chronic bronchitis exacerbation were studied in pre-prone semirecumbent (SREC), prone and post-prone SREC postures. Static respiratory system intrinsic positive end-expiratory pressure (PEEPi,rs) was >12 cmH2O. Haemodynamics, partitioned respiratory mechanics, gas exchange, and lung volumes were determined at zero external positive end-expiratory pressure. P–V curves were constructed from functional residual capacity.End-expiratory lung volume exceeded opening volume. Prone positionversuspre-prone SREC resulted in 20% reduced pressure at the lower inflection point (LIP) and 17% increased volume at the upper inflection point of the lung P–V curve, improved lung mechanics and volumes, oxygenation, and carbon dioxide arterial tension (Pa,CO2). In multiple linear regression, postural decreases in PEEPi,rsand additional lung resistance independently predicted postural decreases in lung LIP pressure andPa,CO2, respectively.In conclusion, in severely hyperinflated patients, pronation reduces lung lower inflection point pressure and increases lung upper inflection point volume. Pronation effects on ventilation homogeneity and carbon dioxide arterial tension are maximised, implying that pronation can be useful during early controlled ventilation.
Integrated care prevents hospitalisations for exacerbations in COPD patients
Authors: Casas A. , Troosters T. , Garcia-Aymerich J. , Roca J. , Hernández C. , Alonso A. , del Pozo F. , de Toledo P. , Antó J. M. , Rodríguez-Roisín R. , Decramer M. 
Published: April 2006

Hospital admissions due to chronic obstructive pulmonary disease (COPD) exacerbations have a major impact on the disease evolution and costs. The current authors postulated that a simple and well-standardised, low-intensity integrated care intervention can be effective to prevent such hospitalisations.Therefore, 155 exacerbated COPD patients (17% females) were recruited after hospital discharge from centres in Barcelona (Spain) and Leuven (Belgium). They were randomly assigned to either integrated care (IC; n = 65; age mean±sd70±9 yrs; forced expiratory volume in one second (FEV1) 1.1±0.5 L, 43% predicted) or usual care (UC; n = 90; age 72±9 yrs; FEV11.1±0.05 L, 41% pred). The IC intervention consisted of an individually tailored care plan upon discharge shared with the primary care team, as well as accessibility to a specialised nurse case manager through a web-based call centre.After 12 months’ follow-up, IC showed a lower hospitalisation rate (1.5±2.6versus2.1±3.1) and a higher percentage of patients without re-admissions (49versus31%) than UC without differences in mortality (19versus16%, respectively).In conclusion, this trial demonstrates that a standardised integrated care intervention, based on shared care arrangements among different levels of the system with support of information technologies, effectively prevents hospitalisations for exacerbations in chronic obstructive pulmonary disease patients.
High ICAM-1 gene expression in pulmonary fibroblasts of COPD patients: a reflection of an enhanced immunological function
Authors: Zandvoort A. , van der Geld Y. M. , Jonker M. R. , Noordhoek J. A. , Vos J. T. W. M. , Wesseling J. , Kauffman H. F. , Timens W. , Postma D. S. 
Published: April 2006

Chronic obstructive pulmonary disease (COPD) is characterised by destruction of extracellular matrix (ECM) in parenchymal areas, whereas the bronchial walls can show fibrosis. In addition, an extensive inflammatory process is observed. CD8+ T-cells, located throughout the lung, and epithelial cells in centrally located airways, produce cytokines involved in the inflammatory process. These cytokines may influence the present fibroblasts, the key effectors in the defective ECM repair and maintenance in COPD.The current authors explored the effects of the cytokine microenvironment on cell–cell interaction gene expression in pulmonary fibroblasts of controls (n = 6), and Global Initiative for Chronic Obstructive Lung Disease stage II (n = 7) and stage IV (n = 7) COPD patients. The current authors simulated thein vivomicroenvironment using supernatants of CD3/CD28 stimulated CD8+ T-cells isolated from peripheral blood of COPD patients, supernatant of a bronchial-epithelial cell line, or a combination of both.The present data show that fibroblasts of chronic obstructive pulmonary disease patients display an altered response to the cytokine microenvironment, depending on both the disease stage and the central or peripheral location in the lung. Especially adhesion-related genes are upregulated in fibroblasts of chronic obstructive pulmonary disease patients, which can indicate a more pronounced role of fibroblasts in the inflammatory process in chronic obstructive pulmonary disease, possibly resulting in reduced function as effectors of extracellular matrix repair.
COPD is associated with increased mortality in patients with community-acquired pneumonia
Authors: Restrepo M. I. , Mortensen E. M. , Pugh J. A. , Anzueto A. 
Published: April 2006

Patients with chronic obstructive pulmonary disease (COPD) who develop community-acquired pneumonia (CAP) may experience worse clinical outcomes. However, COPD is not included as a distinct diagnosis in validated instruments that predict mortality in patients with CAP. The aim of the present study was to evaluate the impact of COPD as a comorbid condition on 30- and 90-day mortality in CAP patients. A retrospective observational study was conducted at two hospitals. Eligible patients had a discharge diagnosis and radiological confirmation of CAP.Among 744 patients with CAP, 215 had a comorbid diagnosis of COPD and 529 did not have COPD. The COPD group had a higher mean pneumonia severity index score (105±32versus87±34) and were admitted to the intensive care unit more frequently (25versus18%). After adjusting for severity of disease and processes of care, CAP patients with COPD showed significantly higher 30- and 90-day mortality than non-COPD patients.Chronic obstructive pulmonary disease patients hospitalised with community-acquired pneumonia exhibited higher 30- and 90-day mortality than patients without chronic obstructive pulmonary disease. Chronic obstructive pulmonary disease should be evaluated for inclusion in community-acquired pneumonia prediction instruments.
The efficacy of bosentan in inoperable chronic thromboembolic pulmonary hypertension: a 1-year follow-up study
Authors: Hughes R. J. , Jais X. , Bonderman D. , Suntharalingam J. , Humbert M. , Lang I. , Simonneau G. , Pepke-Zaba J. 
Published: April 2006

The treatment of choice for chronic thromboembolic pulmonary hypertension (CTEPH) is pulmonary endarterectomy (PEA). However, many patients develop a severe progressive small vessel pulmonary arteriopathy that is inaccessible to surgical intervention and is associated with poor survival. The purpose of the present study was to evaluate the medium-term efficacy and safety of the dual endothelin receptor antagonist, bosentan, in inoperable CTEPH.Forty-seven patients with inoperable CTEPH (distal disease or persistent pulmonary hypertension following PEA) underwent evaluation after 1 yr of bosentan therapy. Outcomes included assessment of 6-min walk test (6MWT), haemodynamics and World Health Organization functional classification. Monitoring of serious adverse effects and changes in therapy was undertaken.Patients showed sustained improvements in 6MWT (49±8 m), functional classification, cardiac index (+0.2±0.07 L·min-1·m-2) and total pulmonary resistance (-139±42 dyn·s·cm-5). Those patients with persisting pulmonary hypertension following PEA showed the greatest improvement. One-yr survival was 96%, and bosentan was well tolerated with only one patient developing deranged liver function.Although all patients with chronic thromboembolic pulmonary hypertension should be considered for pulmonary endarterectomy, bosentan provides an alternative medical therapy to improve function and delay the progression of this devastating disease in those in whom surgery is not suitable.
Binary and ternary liquid metal—steam cycles for high-efficiency coal power stations
Authors: Angelino G , Invernizzi C 
Published: April 2006

Since in the use of coal the direct recourse to combined cycles is impractical, binary alkali metal steam cycles are recognized as an interesting and feasible option. Past attempts to employ metal vapour conversion cycles for power generation are surveyed. After selecting potassium and cesium as possible candidate fluids, the binary cycle is optimized taking as variables the top temperature, the number of condensation levels of the metal vapour cycle, and the characteristics of the bottoming steam cycle. At vaporization temperatures in the range of 750—850 °C, metal vapour cycle efficiencies of about 20—24 per cent and binary cycle efficiencies of 57—61 per cent seem achievable. A survey of available building materials in the steel and in the super-alloy class showed that top temperatures of 800–850 °C could be reached with state-of-the-art alloys. Metal vapour turbines are recognized as a key issue of binary plant design in that exhaust volume flows are very large even for a moderate turbine capacity. For a double flow solution, limiting turbine dimensions to those of existing 1500 r/min steam low pressure stages leads to metal vapour turbine capacity of 120 MW for potassium and 170 MW for cesium. Assuming that in the future, better materials will be available allowing alkali metal vaporization temperatures in the range of 1400–1500 °C, a ternary solution is proposed which employs lithium, potassium, and steam as working fluids. At 1450 °C top temperature, a cycle efficiency in excess of 70 per cent is attained.