1,720,970 research outputs found
Estrogen induced expansion of the growth fraction in receptor negative human breast cancer.
No full textThe feasibility of a cytokinetic chemotherapy based on estrogenic recruitment has been evaluated in 5 patients, affected by locally advanced breast cancer with low or absent receptor content. Tumor proliferative activity was evaluated by the thymidine labeling index (TLI) and the primer-dependent alpha DNA polymerase assay (PDP-LI) which gives an in vitro estimation of tumor growth fraction. The patients have been treated with diethylstilbestrol (DES) 1 mg/die. for 3 days, followed by FAC (5-Fluorouracil 600 mg/m2, Adriamycin 50 mg/m2, Cytoxan 600 mg/m2) i.v. on day 4 q. 21 days. Radical surgery was performed after 3 DES-FAC regimens. Tumor biopsies for evaluation of tumor proliferative activity were performed immediately before and after DES and 24 h after chemotherapy. Our results demonstrate that DES was able to induce an increase in TLI in 3/5 of the patients while the PDP-LI was significantly increased in 5/5 of the patients; subsequent chemotherapy induced a sharp decrease in tumor proliferation. These results provide the rationale for the design of cytokinetic regimens where chemotherapy is administered at the time of estrogen induced tumor cell recruitment
Evaluation of growth fractions with monoclonal antibodies to human alpha-DNA polymerase.
No full textWe have established and partially characterized a panel of monoclonal antibodies against alpha-DNA polymerase. One of the hybridomas, clone 5F, has been exploited for cell kinetic studies on three colon cancer cell lines, LOVO, SW 620, and SW 403, which are endowed with different growth patterns and differentiation status. By an immunoperoxidase method, we could demonstrate the specific intranuclear localization of alpha-DNA polymerase during the exponential phase of in vitro growth and contrast it with the diffuse distribution of the enzyme throughout the cytoplasm during the resting state. The percentage of intranuclear staining positive cells, evaluated at successive time points of in vitro growth, changed from 75 to 95\% (assayed on Days 3 and 7) to 15 to 25\% in confluent and resting populations assayed on Days 12 to 14. In agreement with the assumption that the enzyme moves from nucleus to cytoplasm after entering quiescence, alpha-DNA polymerase was still present in the cytoplasm or in the cytoplasmic perinuclear area of cells in resting phase cultures. Comparisons between traditional kinetic parameters (thymidine labeling index and primer-dependent alpha-DNA polymerase) and proliferative state determined by the monoclonal antibody supported the feasibility of this approach to define the proportion of actively proliferating elements in a tumor cell population. Moreover, parallel flow cytometric analysis performed on Days 5 and 14 of continuous culture showed fluctuations of alpha-DNA polymerase content in relation to exponential and steady-state phases, with a significant increase in the amount of alpha-DNA polymerase in actively proliferating populations and a progressive reduction of the enzyme as the cultures entered the resting stage
Chemotherapy following estrogen-induced expansion of the growth fraction of human breast cancer.
No full textWe have evaluated the feasibility of a cytokinetically oriented regimen based on the induction of cell recruitment by diethylstilbestrol (DES) in locally advanced human breast cancer. Tumor proliferative activity was evaluated by the thymidine labeling index and the primer-dependent alpha-DNA polymerase labeling index, which gives an in vitro estimation of the growth fraction. Sixteen previously untreated patients received DES (1 mg daily for 3 days) followed by FAC [5-fluorouracil (600 mg/m2): Adriamycin (50 mg/m2): Cytoxan (600 mg/m2)] i.v. on day 4 every 21 days. Radical surgery was delayed to allow for three DES-FAC regimens in responsive patients. Proliferative activity on tumor biopsies was evaluated immediately before and after treatment with DES, 24 h after chemotherapy and, in nine patients, at the time of radical surgery. DES was able to induce a significant increase in thymidine labeling index in 8 of 16 patients, while the primer-dependent alpha-DNA polymerase labeling index was significantly increased in 13 of 16 tumors, independently of their estrogen receptor content. Subsequently administered chemotherapy induced an early decrease in tumor proliferation. In the nine patients submitted to surgery after three DES plus FAC courses, the average thymidine labeling index and primer-dependent alpha-DNA polymerase labeling index were 27.8 and 73\% of the pretreatment values. Our preliminary results provide the rationale for the design of new therapeutic schemes in which antitumor drugs are given at the time of estrogen-induced tumor cell recruitment. Further extended studies are required to establish whether induction of tumor cell recruitment will actually translate into appreciable improvement of the clinical response to chemotherapy
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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