bluuebunny/crossref_metadata_2025_split huggingface dataset:
Excision is indicated for intraductal papilloma of the breast diagnosed on core needle biopsy
Authors: Jaffer Shabnam , Nagi Chandandeep , Bleiweiss Ira J. 
Published: April 2009

AbstractBACKGROUND:Although it has been accepted that intraductal papillomas with atypia or malignancy diagnosed on core needle biopsy require surgical excision, the management of pure intraductal papillomas has been controversial. Because some series reported a small but definite incidence of atypia or malignancy, whereas others claimed that radiologic follow‐up was adequate, this study evaluated results of excision of all pure intraductal papillomas diagnosed on core needle biopsy at this institution.METHODS:By using computerized pathology files from January of 2000 to December of 2004, 200 cases of intraductal papillomas on core needle biopsy were identified. Information regarding excision was available in 104 cases. All specimens were reviewed to confirm both the diagnoses as well as the presence of biopsy site changes in excision specimens, and the findings were correlated with radiologic data.RESULTS:The age of the patients ranged from 25 to 82 years (mean, 55.5). The diagnoses on excision were as follows: intraductal papillomas = 71 cases (68.3%), no residual intraductal papillomas = 16 (15.3%), atypical duct hyperplasia = 8 (7.7%), ductal carcinoma in situ = 6 (5.8%), and invasive carcinoma = 3 (2.9%). In cases with atypia or malignancy, these findings were adjacent to but not in the biopsy site. In cases with atypical duct hyperplasia or ductal carcinoma in situ, a spectrum of histologic changes ranging from florid to atypical duct hyperplasia (14 cases), to ductal carcinoma in situ (6 cases) were present, all involving intraductal papillomas.CONCLUSIONS:The upstage rate of pure intraductal papillomas on core needle biopsy to atypia or malignancy on excision was 16.4%. Because of sampling error and the close proximity of atypia or malignancy to the intraductal papillomas (suggesting precancerous potential), excision was recommended of these lesions diagnosed on core needle biopsy. Close radiologic‐pathologic correlation was important in the evaluation of these lesions. Cancer 2009. © 2009 American Cancer Society.
Change in health‐related quality of life of newly diagnosed cancer patients, cancer survivors, and controls*
Authors: Baker Frank , Denniston Maxine , Haffer Samuel C. , Liberatos Penny 
Published: April 2009

AbstractBACKGROUND:Data from the 1998 Health Outcomes Survey (HOS) of patients who were enrolled in Medicare managed care and follow‐up data from the 2000 HOS resurvey were analyzed to examine changes in health‐related quality of life (HRQOL) of newly diagnosed cancer patients, cancer survivors, and patients without cancer.METHODS:In 1998, the HOS was mailed to a random sample of 279,135 beneficiaries, and 167,096 respondents (60%) returned completed surveys. Those who were diagnosed with cancer (22,747) were frequency age‐matched to an equal number of patients with no cancer. In 2000, the HOS was mailed to the same cohort of beneficiaries. Complete data at both baseline and follow‐up were available on 16,850 individuals for inclusion in the current study.RESULTS:After 2 years, respondents who had been diagnosed with cancer at baseline continued to have lower scores on all but 3 scales of the 36‐item short‐form HRQOL measure. However, there was no evidence that they were declining any faster than or catching up with noncancer patients. Those who had been newly diagnosed with cancer since the baseline survey had lower mean scale scores than the no‐cancer group on all scales and lower mean scores than the cancer survivors on all subscales except Bodily Pain, Vitality, and Mental Health.CONCLUSIONS:This study demonstrated that, after 2 years, cancer survivors continued to have poorer HRQOL than the no‐cancer group. Newly diagnosed cancer patients had poorer quality of life than both the longer term cancer survivors and the no‐cancer group. Cancer 2009. Published 2009 by the American Cancer Society*.
Phase 1 trial of temozolomide plus irinotecan plus O6‐benzylguanine in adults with recurrent malignant glioma
Authors: Quinn Jennifer A. , Jiang Sara Xiaoyin , Reardon David A. , Desjardins Annick , Vredenburgh James J. , Gururangan Sridharan , Sampson John H. , McLendon Roger E. , Herndon James E. , Friedman Henry S. 
Published: April 2009

AbstractBACKGROUND:The current study was a phase 1 clinical trial conducted with patients who had recurrent or progressive malignant glioma (MG). The trial was designed to determine the maximum tolerated dose (MTD) and toxicity of irinotecan (CPT‐11) when administered with temozolomide (TMZ) and O6‐benzylguanine (O6‐BG).METHODS:All 3 drugs, CPT‐11, TMZ, and O6‐BG, were administered on Day 1 of a 21‐day treatment. First, patients were treated with a 1‐hour bolus infusion of O6‐BG at a dose of 120 mg/m2 followed immediately by a 48‐hour continuous infusion of O6‐BG at a dose of 30 mg/m2/d. Second, within 60 minutes of the end of the 1‐hour bolus infusion of O6‐BG, TMZ was administered orally at a dose of 355 mg/m2. Third, 1 hour after administration of TMZ, CPT‐11 was infused over 90 minutes. Patients were accrued to 1 of 2 strata based on CYP3A1‐ and CYP3A4‐inducing antiepileptic drug (EIAED) use; dose escalation was conducted independently within these strata.RESULTS:Fifty‐five patients were enrolled. In both strata, the dose‐limiting toxicities were hematologic and included grade 4 neutropenia, febrile neutropenia, leukopenia, and/or thrombocytopenia. For Stratum 1 (EIAEDs), when TMZ was administered at a dose of 355 mg/m2, the MTD of CPT‐11 was determined to be 120 mg/m2. In contrast, for Stratum 2 (no EIAEDs), when TMZ was administered at a dose of 200 mg/m2, the MTD of CPT‐11 was determined to be 80 mg/m2.CONCLUSIONS:The authors believe that the results of the current study provide the foundation for a phase 2 trial of O6‐BG in combination with CPT‐11 and TMZ in patients with MG. Cancer 2009. © 2009 American Cancer Society.
Natural history, growth kinetics, and outcomes of untreated clinically localized renal tumors under active surveillance
Authors: Crispen Paul L. , Viterbo Rosalia , Boorjian Stephen A. , Greenberg Richard E. , Chen David Y. T. , Uzzo Robert G. 
Published: April 2009

AbstractBACKGROUND:The growth kinetics of untreated solid organ malignancies are not defined. Radiographic active surveillance (AS) of renal tumors in patients unfit or unwilling to undergo intervention provides an opportunity to quantify the natural history of untreated localized tumors. The authors report the radiographic growth kinetics of renal neoplasms during a period of surveillance.METHODS:The authors identified patients with enhancing renal masses who were radiographically observed for at least 12 months. Clinical and pathological records were reviewed to determine tumor growth kinetics and clinical outcomes. Tumor growth kinetics were expressed in terms of absolute and relative linear and volumetric growth.RESULTS:The authors identified 172 renal tumors in 154 patients under AS. Median tumor diameter and volume on presentation were 2.0 cm (mean, 2.5; range, 0.4‐12.0) and 4.18 cm3 (mean, 20.0; range, 0.033‐904). Median duration of follow‐up was 24 months (mean, 31; range, 12‐156). A significant association between presenting tumor size and proportional growth was noted, with smaller tumors growing faster than larger tumors. Thirty‐nine percent (68 of 173) of tumors underwent delayed intervention, and 84% (57 of 68) were pathologically malignant. Progression to metastatic disease was noted in 1.3% (2 of 154) of patients.CONCLUSIONS:The authors demonstrated the association between a tumor's volume and subsequent growth, with smaller tumors exhibiting significantly faster volumetric growth than larger tumors, consistent with Gompertzian kinetics. Surveillance of localized renal tumors is associated with a low rate of disease progression in the intermediate term, and suggests potential overtreatment biases in select patients. Cancer 2009. © 2009 American Cancer Society.
High‐dose chemotherapy and autologous hematopoietic progenitor cell rescue in children with recurrent medulloblastoma and supratentorial primitive neuroectodermal tumors
Authors: Butturini Anna M. , Jacob Mary , Aguajo Jennifer , Vander‐Walde Noam A. , Villablanca Judy , Jubran Rima , Erdreich‐Epstein Anat , Marachelian Araz , Dhall Girish , Finlay Jonathan L. 
Published: April 2009

AbstractBACKGROUND:The role of myeloablative chemotherapy in children with recurrent medulloblastoma and supratentorial primitive neuroectodermal tumors (MB/ST‐PNET) is controversial, in particular in patients who develop recurrent disease after craniospinal radiotherapy.METHODS:In this retrospective analysis, the authors investigated the outcome of children with recurrent MB/ST‐PNET who were referred for myeloablative chemotherapy and autologous hematopoietic progenitor cell rescue at Childrens Hospital Los Angeles.RESULTS:Thirty‐three children were referred for myeloablative chemotherapy: Fourteen of those children were never transplanted because of pre‐transplant adverse events, and 19, including 6 without and 13 with previous irradiation, underwent transplant. Conditioning regimens included a backbone of thiotepa, which was given either in a single cycle or in multiple sequential cycles. The 3‐year post‐transplant event‐free survival rate in unirradiated versus previously irradiated children was 83% ± 15% versus 20% ± 12%, respectively (P = .04). One child who had never been exposed to radiotherapy died of toxicity; the other children received post‐transplant radiotherapy and remained disease free. Nine previously irradiated children experienced 4 toxic deaths and 6 tumor recurrences (1 patient had both): An interval of <1 year between initial radiotherapy and myeloablative chemotherapy predicted a greater risk of toxic death (P = .02), whereas a history of meningeal metastases at diagnosis and a poor response to the initial rescue therapy predicted a greater risk of post‐transplant recurrence (P = .03 and P = .08, respectively).CONCLUSIONS:Myeloablative doses of thiotepa‐based chemotherapy and radiotherapy were able to cure most children who had radiotherapy‐naive, chemoresponsive recurrences. Children who developed recurrences after craniospinal radiotherapy had poorer outcomes; however, cure was possible in those who had good prognostic features at presentation, chemoresponsive recurrences, and a long interval between initial radiotherapy and myeloablative chemotherapy. Cancer 2009. © 2009 American Cancer Society.
Quenched large deviations for random walk in a random environment
Authors: Yilmaz Atilla 
Published: April 2009

AbstractWe take the point of view of a particle performing random walk with bounded jumps on ℤd in a stationary and ergodic random environment. We prove the quenched large‐deviation principle (LDP) for the pair empirical measure of the so‐called environment Markov chain. By an appropriate contraction, we deduce the quenched LDP for the mean velocity of the particle and obtain a variational formula for the corresponding rate function. We propose an ansatz for the minimizer of this formula. When d = 1, we verify this ansatz and generalize the nearest‐neighbor result of Comets, Gantert, and Zeitouni to walks with bounded jumps. © 2009 Wiley Periodicals, Inc.
Experimental comparison of phase‐noise in cross‐coupled RC‐ and LC‐oscillators
Authors: Oliveira Luis Bica , Allam Ahmed , Filanovsky Igor M. , Fernandes Jorge R. , Verhoeven Chris J. M. , Silva Manuel M. 
Published: April 2009

AbstractRelaxation RC‐oscillators are notorious for their poor phase‐noise performance. However, there are reasons to expect a phase‐noise reduction in quadrature oscillators obtained by cross‐coupling two relaxation oscillators. We present measurements on 5 GHz oscillators, which show that in RC‐oscillators the coupling reduces both the phase‐noise and quadrature error, whereas in LC‐oscillators the coupling reduces the quadrature error, but increases the phase‐noise. A comparison using standard figures of merit indicates that quadrature RC‐oscillators may be a viable alternative to LC‐oscillators when area and cost are to be minimized. Copyright © 2009 John Wiley & Sons, Ltd.
A single‐stage phase‐shifted full‐bridge AC/DC converter with variable frequency control
Authors: Chiu Huang‐Jen , Lo Yu‐Kang , Lee Ting‐Peng , Chuang Ching‐Chun , Mou Shann‐Chyi 
Published: April 2009

AbstractThis letter presents a single‐stage soft‐switched full‐bridge AC/DC converter for low‐voltage/high‐current output applications. A phase‐shifted method with a variable frequency control is used to regulate the DC bus voltage and the output voltage of the single‐stage AC/DC converter. The proposed circuit topology and control scheme exhibit superior performances (i.e. high power factor, high‐efficiency, and ring‐free features). Correspondingly, a laboratory prototype, 500 W 5V/100A AC/DC converter, is implemented to verify the feasibility of the proposed design. Copyright © 2009 John Wiley & Sons, Ltd.
Capacity lower bound and energy efficiency of training‐based MIMO systems over correlated channels
Authors: Pang Jiyong , Li Jiandong , Jin Shan 
Published: April 2009

AbstractThe behavior of training‐based multiple‐input multiple‐output wireless communications over correlated channels is studied in the low signal‐to‐noise ratio (SNR) regime from an energy efficiency perspective. To start with, a relaxed but analytically more tractable capacity lower bound is derived where the impacts of channel spatial correlation are considered simply through the ranks of correlation matrices. It shows that, different from the independent and identically distributed case, the optimal training length no longer equals the number of transmit antennas but is just the same as the rank of transmit correlation matrix. Next, the bit energy requirements are analyzed based on the derived capacity lower bound. It shows that the minimum bit energy required for reliable communication is achieved at a nonzero SNR value below, which the bit energy grows to infinity with a zero‐approaching wideband slope. Flash training and transmission scheme is also studied and shown to improve the energy efficiency. In addition, the impacts of spatial correlation, channel coherence interval and antenna number on the energy efficiency are analyzed. It shows that stronger spatial correlation leads to less bit energy, i.e. higher‐energy efficiency. The minimum bit energy is achieved at lower SNR in a more correlated channel. Spatial correlation also helps to reduce the signal peakiness in the flash scheme. And larger coherence interval always improves energy efficiency at all SNR. Finally, the validity of the proposed results is verified by numerical simulations. Copyright © 2009 John Wiley & Sons, Ltd.
Mechanistic Information on CuII Metalation and Transmetalation of Chlorophylls
Authors: Orzeł Łukasz , van Eldik Rudi , Fiedor Leszek , Stochel Grażyna 
Published: April 2009

AbstractChlorophyll a and pheophytin a have been treated with various metal salts in solution. As a result, metallo derivatives of photosynthetic pigments were formed, or the chlorine ring was oxidized. These studies showed that both effects can be caused by CuII ions depending on the redox potential of its complexes formed in specific media. In this report the results of studies on metal insertion and exchange reactions are presented. According to the common use of the “acetate method” in the synthesis of metallotetrapyrroles, and the fact that acetates coordinated to CuII ions protect chlorophylls from oxidative degradation, CuII acetate monohydrate was selected as main reagent. The metalation and transmetalation processes were investigated with spectroscopic (UV/Vis absorption and emission) and kinetic (conventional and high‐pressure) techniques. It turned out that differences in solvent properties can significantly affect not only the rates (metalation), but also the course (transmetalation) of the reaction. The most pronounced effect was found for the transmetalation reaction in acetonitrile, which was terminated at the very initial stage. As shown elsewhere, some special agents/factors, such as excess of acetate, are required to facilitate the dissociation of Mg2+ and to push the reaction forward towards formation of the CuII derivative of chlorophyll. The mechanisms of two other reactions are proposed on the basis of the determined activation parameters, which correspond to the general mechanisms for metalation and transmetalation of tetrapyrroles with sitting‐atop and bimetallic intermediates, respectively. The bimetallic complex of chlorophyll in methanol is probably the most stable complex of this type observed ever. It confirms that spontaneous exchange of Mg2+ by CuII occurring in plants must result from specific conditions and/or involve contribution from other components of the photosystem.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Potentiometric, Spectroscopic and DFT Study of the VIVO Complexes Formed by Di(pyridin‐2‐yl) Ligands
Authors: Pisano Luisa , Kiss Dóra , Várnagy Katalin , Sanna Daniele , Micera Giovanni , Garribba Eugenio 
Published: April 2009

AbstractThe coordinating properties of a series of di(pyridin‐2‐yl) derivatives towards the VIVO2+ ion have been studied through the combined application of potentiometric and spectroscopic (electronic absorption and EPR spectroscopies) methods. In particular, di(pyridin‐2‐yl)amine (DPA), di(pyridin‐2‐yl)methane (DPM), di(pyridin‐2‐yl) ketone (DPK), di(pyridin‐2‐yl)methanol (DPMO), 2‐acetylpyridine (2‐AP) and 2‐hydroxymethylpyridine (2‐HMP), and two amino acid derivatives of di(pyridin‐2‐yl)methylamine (DPMA), namely N‐glycyl‐DPMA and N‐histidyl‐DPMA, have been examined. The stability constants of proton and VIVO complexes (logβ) were measured at 25 °C and at a constant ionic strength of 0.2 M (KCl). The results show that the simple di(pyridin‐2‐yl) derivatives having only pyridine nitrogen atoms form mono‐chelated species with the (Npyr, Npyr) donor set, whereas those provided with carbonyl or hydroxy groups form mono‐ and bis‐chelated complexes with (Npyr, CO) or (Npyr, O–) coordination. The square pyramidal species with 2×(Npyr, O–) coordination exists in equilibrium with the octahedral isomer, which has an axially bound water molecule and is characterized by an anomalously low value of the 51V hyperfine coupling constant along the z‐axis (Az). DFT calculations were used to optimize the geometry of the complexes and to predict the Az values measured in the EPR spectra for the penta‐ and hexacoordinate complexes formed by DPK, DPMO, 2‐AP and 2‐HMP and for the [VOLH–1]+ and[VOLH–2] species formed by the amino acid derivatives of DPMA. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Dependence of DNA double strand break repair pathways on cell cycle phase in human lymphoblastoid cells
Authors: Takashima Yoshio , Sakuraba Mayumi , Koizumi Tomoko , Sakamoto Hiroko , Hayashi Makoto , Honma Masamitsu 
Published: April 2009

AbstractDNA double‐strand breaks (DSBs) are usually repaired by nonhomologous end‐joining (NHEJ) or homologous recombination (HR). NHEJ is thought to be the predominant pathway operating in mammalian cells functioning in all phases of the cell cycle, while HR works in the late‐S and G2 phases. However, relative contribution, competition, and dependence on cell cycle phases are not fully understood. We previously developed a system to trace the fate of DSBs in the human genome by introducing the homing endonuclease I‐SceI site into the thymidine kinase (TK) gene of human lymphoblastoid TK6 cells. Here, we use this system to investigate the relative contribution of HR and NHEJ for repairing I‐SceI‐induced DSBs under various conditions. We used a novel transfection system, Amaxa™ nucleofector, which directly introduces the I‐SceI expression vector into cell nuclei. Approximately 65% of transfected cells expressed the I‐SceI enzyme and over 50% of the cells produced a single DSB in the genome. The relative contribution of NHEJ and HR for repairing the DSB was ∼100:1 and did not change with transfection efficiency. Cotransfection with KU80‐siRNA significantly diminished KU80 protein levels and decreased NHEJ activity, but did not increase HR. We also investigated HR and NHEJ in synchronized cells. The HR frequency was 2–3 times higher in late‐S/G2 phases than in G1, whereas NHEJ was unaffected. Even in late‐S/G2 phases, NHEJ remained elevated relative to HR. Therefore, NHEJ is the major pathway for repairing endonuclease‐induced DSBs in mammalian cells even in late‐S/G2 phase, and does not compete with HR. Environ. Mol. Mutagen. 2009. © 2009 Wiley‐Liss, Inc.
The functional significance of centrosomes in mammalian meiosis, fertilization, development, nuclear transfer, and stem cell differentiation
Authors: Schatten Heide , Sun Qing‐Yuan 
Published: April 2009

AbstractCentrosomes had been discovered in germ cells and germ cells continue to provide excellent but also challenging material in which to study complex centrosomal dynamics. The present review highlights the importance of centrosomes for meiotic spindle integrity and the susceptibility of meiotic spindle centrosomes to aging and drugs or toxic agents which may be associated with female infertility, aneuploidy, and developmental abnormalities. We discuss cell and molecular aspects of centrosomes during fertilization, a critical stage in which centrosomes play crucial roles in precisely organizing the sperm aster that allows apposition of male and female genomes followed by formation of the zygote aster that is important for the formation of the bipolar spindle apparatus during cell division. Development of an embryo involves sequential cell divisions in which centrosomes play a critical role in establishing asymmetry that allows differentiation of cells and targeted signal transductions for the developing embryo. Asymmetric centrosome dynamics are also critical for stem cell division to maintain one daughter cell as a stem cell while the other daughter cell undergoes centrosome growth in preparation for differentiation. This review also discusses the complex interactions of somatic cell centrosomes with the recipient oocyte in reconstructed (cloned) embryos in which centrosome remodeling is crucial to fulfill functions that are carried out by the zygote centrosome in fertilized eggs. We close our discussion with a look at centrosome dysfunctions and implications for male fertility and assisted reproduction. Environ. Mol. Mutagen. 2009. © 2009 Wiley‐Liss, Inc.