bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isolation of Rhenium and ReOx Species within ZSM5 Channels and their Catalytic Function in the Activation of Alkanes and Alkanols
Authors: Lacheen Howard S. , Cordeiro Paul J. , Iglesia Enrique 
Published: February 2007

AbstractSynthesis protocols, structures, and reactivity of Re–oxo species grafted onto HZSM5, and their subsequent conversion to Re‐clusters through contact with H2 or CH4 were studied by using Raman, infrared, and X‐ray absorption spectroscopies. Reactivity measurements by using alkane and alkanol reactants were also examined. Sublimation of Re2O7 at 723 K led to a stoichiometric exchange with each ReOx species replacing one proton. Raman features for Re2O7 disappeared during thermal treatment and Raman bands assigned to distorted‐tetrahedral Si‐OfReO3‐Al (Of: zeolite‐lattice oxygen atoms) species emerged; infrared bands for acidic OH groups in HZSM5 weakened concurrently. X‐ray absorption near‐edge and fine‐structure spectra detected the formation of distorted‐tetrahedral Re7+–oxo species during thermal treatment of Re2O7/HZSM5 mixtures in air, and their subsequent reduction to Re0 in H2 or CH4 to form encapsulated Re metal clusters similar in diameter (≈8 Å) to the channel intersections in ZSM5. Si‐OfReO3‐Al species in ReOxZSM5 catalyzed the oxidative conversion of C2H5OH to acetaldehyde, acetal, and ethyl acetate with very low selectivity to COx (<1 %). Unprecedented turnover rates were exhibited at temperatures much lower than previously found for ReOx–based catalysts, and without deactivation or sublimation processes ubiquitous in crystalline Re7+ compounds at temperatures required for catalysis. Encapsulated Re metal clusters formed by the reduction of Si‐OfReO3‐Al precursors led to CH4 pyrolysis and C3H8 dehydrocyclodimerization rates (per Re) that are higher than those previously reported for zeolite‐based catalysts. The rate of CH4 conversion to benzene, by using ReZSM5, was ≈30 % higher than that of the best reported catalysts, based on encapsulated MoCx clusters, whereas C2H4 and C6+ arene selectivities were similar. C3H8 activity and selectivity of ReZSM5 was significantly higher than that of GaZSM5, the best reported catalyst for these reactions. Reaction rates (per Re) were independent of the Re/Alf (Alf: aluminum framework) ratio for both Re and ReOx species. This is consistent with the uniform character of the structures formed during grafting of the ReOx species through sublimation and their ability to retain their homogeneity even after their reduction to encapsulated Re‐clusters.
Rearrangement of a (Dithiolato)platinum(II) Complex Formed by Reaction of Cyclic Disulfide 7,8‐Dithiabicyclo[4.2.1]nona‐2,4‐diene with a Platinum(0) Complex: Oxidation of the Rearranged (Dithiolato)platinum(II) Complex
Authors: Ishii Akihiko , Kashiura Satoshi , Hayashi Yuichi , Weigand Wolfgang 
Published: February 2007

AbstractReaction of the title bicyclic disulfide 16 with [(Ph3P)2Pt(η2‐C2H4)] (2) yielded the corresponding (dithiolato)platinum(II) complex 17 by oxidative addition. The initial product 17 isomerized at room temperature in a [1,5]‐sulfur rearrangement to give another (dithiolato)platinum(II) complex 18 in high isolated yield. Oxidation reactions of 18 with dimethyldioxirane (DMD) provided (sulfenato‐thiolato)platinum(II) 23, (sulfinato‐thiolato)platinum(II) 24, (sulfenato‐sulfinato)platinum(II) 25, and (disulfinato)platinum(II) 26 complexes, the structures of which were elucidated by NMR spectroscopy and X‐ray crystallography. The oxidation process took place regioselectively in the first step and chemoselectively in the second. The selectivities are discussed.
An Improved Catalyst System for the Iron‐Catalyzed Intermolecular Ring‐Expansion Reactions of Epoxides
Authors: Hilt Gerhard , Bolze Patrick , Harms Klaus 
Published: February 2007

AbstractA considerable improvement is reported in the iron‐catalyzed ring‐expansion reactions of epoxides generating tetrahydrofuran derivatives by formal insertion of an alkene. Optimization of the catalyst system revealed that a preformed [Fe(salen)] complex minimizes the formation of polymerization side‐products so that increased yields of intermolecular reactions were obtained. However, more importantly, the scope of the reaction could also be enlarged considerably. The iron‐catalyzed ring‐expansion reaction can now be applied to some styrene oxide derivatives, acting as radical donors, as well as to a wide variety of acceptor‐substituted acyclic alkenes and cyclic dienes that act as radical acceptors. The use of unsymmetrical radical acceptors led to interesting questions concerning the regiochemistry of the reactions. The conservation of the stereochemistry of the starting materials in the products was investigated through a study of the reactions of E‐ and Z‐configured acceptor‐substituted double bonds. The reactions of fumaric and maleic esters were performed and the ratios of diastereomeric and regioisomeric products were determined.
Luminescent Nanocrystals for Nonenzymatic Glucose Concentration Determination
Authors: Wang Leyu , Li Yadong 
Published: February 2007

AbstractBy using a facile, wet‐chemical approach, luminescent LaF3:Ce3+/Tb3+ single‐crystal nanoparticles were prepared from nitrate and sodium fluoride precursors in a mixture of ethanol and ethylene glycol. These nanoparticles were functionalized with glucose. A novel fluorescence resonance energy transfer method for nonenzymatic glucose determination has been developed by using these glucose‐modified nanocrystals. Under the chosen conditions, concentrations of glucose between 0.5 and 25.0 mmol L−1 in aqueous solutions were successfully determined. Owing to their high luminescence and good dispersibility in water, these nanocrystals are also potential fluorescent biolabels for other biological and clinical applications, such as in fluorescence imaging and for immunoassays.
Coronary microvascular reactivity is only partially predicted by atherosclerosis risk factors or coronary artery disease in women evaluated for suspected ischemia: results from the NHLBI Women's Ischemia Syndrome Evaluation (WISE)
Authors: Wessel Timothy R. , Arant Christopher B. , McGorray Susan P. , Sharaf Barry L. , Reis Steven E. , Kerensky Richard A. , von Mering Gregory O. , Smith Karen M. , Pauly Daniel F. , Handberg Eileen M. , Mankad Sunil , Olson Marian B. , Johnson B. Delia , Bairey Merz C. Noel , Sopko George , Pepine Carl J. 
Published: February 2007

AbstractBackgroundAltered coronary reactivity is frequent in women with findings of myocardial ischemia without significant obstructive disease. This suggests a defect in coronary microvascular function. The adenosine‐related component of this altered reactivity has been described in male and mixed gender populations, while the factors influencing this component of coronary reactivity in symptomatic women have received limited attention. Accordingly, the relationship between adenosine‐related microvascular coronary reactivity and risk factors in symptomatic women evaluated for suspected ischemia remains uncertain.HypothesisAbnormal coronary microvascular reactivity to adenosine is predicted by atherosclerosis risk factors in women.MethodsAs part of the NHLBI‐sponsored Women's Ischemia Syndrome Evaluation (WISE), we investigated the relationship between risk factors and coronary microvascular reactivity as flow velocity reserve to intracoronary adenosine (CFVRAdo) in 210 women referred for angiography to evaluate suspected ischemia.ResultsUnivariate analyses identified associations between CFVRAdo and multiple risk conditions; however, after adjusting for age, none remained significant. The best multivariable model using combinations of risk conditions to predict CFVRAdo yielded an R2 of only 0.18.ConclusionsAmong women with suspected ischemia, risk factors account for <20% of observed variability in CFVRAdo. Therefore, other as yet unidentified factors must primarily account for coronary microvascular reactivity to adenosine. Copyright © 2007 Wiley Periodicals, Inc.
Cardiac Syncope in Pediatric Patients
Authors: Massin Martial M. , Malekzadeh‐milani Sophie , Benatar Avram 
Published: February 2007

AbstractObjectiveTo assess the epidemiology of cardiac syncope in children and evaluate the guidelines on its management.Material and methodsWe analyzed the etiology to syncope and diagnostic workup in consecutive pediatric patients presenting with syncope in our emergency departments or cardiac outpatient clinics between 1997 and 2005, and who were subsequently diagnosed as having cardiac syncope.ResultsA primary cardiac cause was identified in 11 syncopal patients presenting to the emergency room and 14 patients to the cardiac clinic: supraventricular tachyarrhythmia in 9, ventricular tachyarrhythmia in 10, pacemaker dysfunction in 2, and isolated cases of sick sinus syndrome, hypoxic spell, hypertrophic cardiomyopathy, and primary pulmonary hypertension. Some elements suggested potential cardiac disease as a cause of syncope in all cases. The resting electrocardiogram and the echocardiogram were interpreted as positive and relevant to the diagnosis in 17 and 3 patients, respectively. Exercise electrocardiogram and Holter recording provided diagnostic information previously not seen on the resting electrocardiogram in six and three patients, respectively. Three children have died and one child has neurological sequelae following resuscitation.ConclusionOur data support the premise that careful history taking with special focus on the events leading up to syncope, as well as a complete physical examination, can guide practitioners in discerning which syncopal children need further cardiac investigations. Copyright © 2007 Wiley Periodicals, Inc.
Spectral properties of a bifunctional PARACEST europium chelate: an intermediate for targeted imaging applications
Authors: Adair Christopher , Woods Mark , Zhao Piyu , Pasha Azhar , Winter Patrick M. , Lanza Gregory M. , Athey Phillip , Sherry A. Dean , Kiefer Garry E. 
Published: February 2007

AbstractThis report describes a preliminary study to investigate the effect of structural variations in a bifunctional ligand being developed for targeted PARACEST applications. Utilizing Eu‐DOTA‐4AmCE as the functional PARACEST core, a nitro‐aromatic functionality was incorporated to provide the point for conjugation. This intermediate possesses a coordinated water proton signal at 57 ppm which upon saturation produces a 22% decrease in bulk water signal intensity using 10 mM agent. Curve fitting analysis of the CEST spectrum to an exchange model based upon modified Bloch equations gave an estimate of 687 ± 100 µs for the bound water lifetime (τm). Although substantially longer than the 382 µs observed for the parent chelate structure, this water exchange rate remains in the necessary window to produce a significant CEST effect. These findings demonstrate the need to recognize the influence of bifunctional linkers on water exchange rates in lanthanide complexes of this type and the potential for using this functionality as a means of fine‐tuning PARACEST performance. Copyright © 2007 John Wiley & Sons, Ltd.
Diagnosis and management of chronic myeloid leukemia
Authors: Kantarjian Hagop M. , Cortes Jorge , Guilhot Francçois , Hochhaus Andreas , Baccarani Michele , Lokey Lee 
Published: February 2007

AbstractBACKGROUND.The success of imatinib therapy for chronic myeloid leukemia (CML) has brought new challenges; these include optimizing disease monitoring, imatinib resistance, and use of novel, more potent tyrosine kinase inhibitors. Thus, there is a need to establish new best practices for CML management in the post‐imatinib era.METHODS.An internet‐based questionnaire, consisting of 26 multiple choice questions, was developed to assess hematologists' and oncologists' self‐reported treatment strategies for CML.RESULTS.Between November 2005 and January 2006, 956 eligible physicians responded to the survey; 727 from the US and 229 from Europe. Most US respondents (60%) practiced in the community setting, whereas European respondents were primarily academic (44%) and hospital‐based (40%). Physicians' responses were generally in line with current recommendations, although differences were identified. Confusion existed among respondents over optimal timing of treatment decisions, with a notable proportion of physicians focusing on a single timepoint rather than consistent monitoring, as currently advocated. Some respondents were unaware of new molecular monitoring techniques, when to monitor for BCR‐ABL mutations (and the impact on treatment decisions), and the benefit of new tyrosine kinase inhibitors.CONCLUSIONS.Responses to the survey suggest that treatment practices in some areas of CML management are not in line with current recommendations. Identified areas of need should be targeted in future educational activities for the CML community. Cancer 2007. © 2007 American Cancer Society.
Catheter‐related bloodstream infections in hematology
Authors: Worth Leon J. , Slavin Monica A. , Brown Graham V. , Black James 
Published: February 2007

AbstractCentral venous catheters are essential in the management of many malignant disorders, but catheter‐related bloodstream infections (CR‐BSIs) are significant complications in terms of morbidity, mortality, and healthcare expenditure. These outcome measures are useful for monitoring of infection control practice and the effect of preventive strategies. Unlike intensive care unit (ICU) populations, surveillance for CR‐BSIs in the hematology population is not standardized, despite the potential value of detecting changes in rate, etiology, and changes in risk for infective complications in association with increasingly intensive chemotherapeutic regimens in this immunocompromised population. Essential components of a successful surveillance strategy include selection of a health outcome of significance, definition of goals of the surveillance system, involvement of key stakeholders in planning and development, application of valid case definitions, allocation of resources and trained personnel, risk stratification, and use of appropriate statistical methods for analysis. These are discussed with reference to patients with hematologic malignancy, together with review of previous surveillance strategies in this population. Only when these issues are addressed can a surveillance strategy reliably assess trends and compare data, leading to improved patient outcomes and a reduction in healthcare expenditure for patients with hematologic malignancy. Cancer 2007. © 2007 American Cancer Society.
Association between pharmaceutical involvement and outcomes in breast cancer clinical trials
Authors: Peppercorn Jeffrey , Blood Emily , Winer Eric , Partridge Ann 
Published: February 2007

AbstractBACKGROUND.Since 1992, pharmaceutical industry support has surpassed National Institutes of Health funding for clinical research in the United States. In this study, the authors sought to evaluate the impact of this shift in funding from public to private sponsors on the nature of published breast cancer clinical research.METHODS.All published breast cancer clinical trials from 2003, 1998, and 1993 were reviewed from 10 select English‐language medical journals to evaluate pharmaceutical involvement over time and the association between sponsorship, trial design, and results. Clinical studies that reported disease‐specific outcomes from medical therapy for breast cancer were eligible for analysis. Pharmaceutical involvement was defined as reported pharmaceutical industry funding, provision of drug, and/or authorship for each publication.RESULTS.In total, 140 eligible studies were identified, including 45 studies that were published in 1993, 39 studies that were published in 1998, and 56 studies that were published in 2003. Among those, 67 publications (48%) reported pharmaceutical industry involvement, 36 publications (26%) had at least ≥1 pharmaceutical industry author, And 100 publications (71%) were considered positive. Pharmaceutical involvement was identified in 44% of the studies published in 1993, in 38% of the studies published in 1998, and in 58% of the studies published in 2003. Pharmaceutical authorship was reported in 22% of the 1993 studies, in 21% of the 1998 studies, and in 34% of the 2003 studies. For studies that were published in 2003, those that reported pharmaceutical involvement were more likely to be positive (84% vs 54%; P = .02; Fisher exact test), to be single‐arm studies (66% vs 33%; P = .03), and to evaluate metastatic disease (72% vs 46%; P = .06).CONCLUSIONS.Pharmaceutical involvement in published clinical breast cancer research may affect study design, focus, and results. Further research is warranted, including analysis of unpublished studies, to evaluate the impact of increasing pharmaceutical industry involvement on clinical research. Cancer 2007;109:. © 2007 American Cancer Society.
Patient variables that predict atypical cytology by nipple duct lavage
Authors: Bushnaq Zinaida I. , Ashfaq Raheela , Leitch A. Marilyn , Euhus David 
Published: February 2007

AbstractBACKGROUND.Nipple duct lavage (NDL) may be useful for breast cancer risk stratification. Published guidelines recommend that women with a 5‐year Gail risk ≥1.7% should consider undergoing lavage for any fluid‐yielding ducts, but it is not known whether increased breast cancer risk or nipple fluid production predict lavage atypia.METHODS.One hundred fifty women unselected for breast cancer risk underwent NDL with cannulation of all nipple aspirate fluid (NAF)‐producing ducts and at least 1 dry duct. This resulted in 516 lavage samples. The rate of cytologic atypia was compared for NAF‐positive ducts and NAF‐negative ducts and for women with 5‐year Gail risks ≥1.7% and <1.7%. Ducts from breasts with cancer (N = 113) were excluded from the analysis.RESULTS.The cytologic atypia rate was similar for the 240 NAF‐producing ducts (19%) and the 163 dry ducts (15%; P = .36). No significant differences were observed when atypia was categorized as mild (13% vs 10%; P = .63) or marked (6% vs 4%; P = .53). Among the 83 patients who were unaffected by breast cancer, atypia was diagnosed in 15 of 44 patients (34%) with a 5‐year Gail risk <1.7% and in 11 of 39 patients (28%) with a 5‐year Gail risk ≥1.7% (P = .74).CONCLUSIONS.Neither NAF production nor 5‐year Gail risk predicted lavage atypia. Limiting NDL to fluid‐producing ducts in women with a 5‐year Gail risk ≥1.7% significantly reduced the sensitivity of the test for population screening. Cancer 2007. © 2007 American Cancer Society.
A prospective study of the impact of nasopharyngeal cancer and radiotherapy on the psychosocial condition of Chinese patients
Authors: Lee Peter W. H. , Kwan Tracy T. C. , Kwong Dora L. W. , Sham Jonathan S. T. , Pow Edmond H. N. , McMillan Anne S. , Au Gordon K. H. 
Published: February 2007

AbstractBACKGROUND.Radiotherapy (RT) promises optimistic results in the treatment of nasopharyngeal cancer (NPC). The objective of the current study was to map out prospectively the impact of NPC and RT on patients from diagnosis to 1 year posttreatment.METHODS.For this study, 67 Chinese patients (46 men and 21 women) with newly diagnosed stage I or II NPC who received primary RT were recruited. Physical and psychosocial adjustments were measured by using the Rotterdam Symptom Checklist, Beck Anxiety Inventory, Beck Depression Inventory, Perceived Stress Scale, and the 36‐item Short‐Form Health Survey (SF‐36). Semistructured clinical interviews were conducted at bimonthly intervals from pre‐RT to 1 year post‐RT.RESULTS.Physical and psychosocial adjustments were poorest from pre‐RT to the end of RT. Rapid improvements in all areas were noted in the first 2 months post‐RT and reached a plateau at around the 6th month. At 1 year, except for physical symptoms and perceived stress, patient measures recovered to their pre‐RT levels. At 1 year, patients had more physical complaints (P < .001) but less perceived stress (P = .002). The percentage of patients who expressed fear of dying dropped from 28% pre‐RT to 2% at 1 year. However, patients who expressed “fear of the worst happening” increased from 51% pre‐RT to 57% at 1 year.CONCLUSIONS.Different periods in treatment of NPC imposed different psychosocial demands on patients. The current results indicated that the period from diagnosis to 2‐month post‐RT was a high‐risk period both physically and emotionally. After treatment, most patients showed resilience despite persistent side effects of RT and successfully resumed their pretreatment level of functioning by the end of the year. Despite resuming a normal or near‐normal living, patients still noted a subdued fear of recurrence. Cancer 2007. © 2007 American Cancer Society.
Osteopenia and cancer in children and adolescents
Authors: Sala Alessandra , Barr Ronald D. 
Published: February 2007

AbstractThe attainment of a satisfactory peak bone mass, which is accomplished largely by the end of adolescence, is the best protection against excessive bone mineral loss in late adulthood. Factors that influence this process include age, race, sex, body size, pubertal status, diet, physical activity, and other lifestyle elements. Cancer and its treatment in children and teenagers adversely impact bone mineralization. In particular, chemotherapy (especially glucocorticosteroids and methotrexate) and cranial irradiation (apparently by reducing growth hormone secretion and by causing hypogonadotropic hypogonadism) interfere with normal bone turnover. Resorption often exceeds formation, resulting in net bone mineral loss and providing a rational basis for the use of antiresorptive drugs. Such osteopenia may be symptomatic, with pain and abnormal gait, and increases the risk of fractures several fold. The disorder is compounded by reduced physical activity, so programs to reduce this deficit are of measurable benefit. All of those engaged in the care of children and adolescents with cancer have an opportunity to improve the bone health of these young people and to limit their risk of developing osteoporosis and fragility fractures in adult life. Cancer 2007;. © 2007 American Cancer Society.
High incidence of hepatitis B virus infection in B‐cell subtype non‐Hodgkin lymphoma compared with other cancers
Authors: Wang Feng , Xu Rui‐hua , Han Bing , Shi Yan‐xia , Luo Hui‐yan , Jiang Wen‐qi , Lin Tong‐yu , Huang Hui‐qiang , Xia Zhong‐jun , Guan Zhong‐zhen 
Published: February 2007

AbstractBACKGROUND.The authors investigated the prevalence of hepatitis B virus (HBV) infection by using serologic markers in non‐Hodgkin lymphoma (NHL) compared with other types of cancers in Chinese patients.METHODS.In this case‐control study, HBV and other hepatitis markers were compared between a study group and a control group. The study group included 587 patients with NHL (age range, 16–86 years), and the control group included 1237 patients (age range, 16–89 years) who were diagnosed with other cancers except liver cancer. An enzyme‐linked immunosorbent assay was used to test serum samples from both groups for HBV markers and other hepatitis markers.RESULTS.Logistic regression analysis showed that there was a higher prevalence of HBV infection in patients with the B‐cell subtype of NHL (30.2%) than in patients with other cancers (14.8%; odds ratio [OR], 2.6; 95% confidence interval [95% CI], 2.0–3.4); however, in patients with the T‐cell subtype of NHL, the HBV infection rate (19.8%) was similar to that among patients with other cancers (OR, 1.2; 95% CI, 0.8–1.8). A significant difference in HBV prevalence was found between B‐cell and T‐cell NHL (OR, 2.3; 95% CI, 1.4–3.6). In the patients with B‐cell NHL, those who were infected with HBV had a significantly earlier disease onset (9.5 years) than those who were not infected with HBV.CONCLUSIONS.The current results demonstrated that patients with B‐cell NHL, but not patients with T‐cell NHL, had a higher prevalence of HBV infection. HBV infection was associated with a significantly earlier disease onset (P < .001), a finding that suggested the possibility that HBV may play an etiologic role in the induction of B‐cell NHL. Cancer 2007. © 2007 American Cancer Society.