1,720,961 research outputs found
Is axillary dissection mandatory following a positive sentinel node biopsy?
No full textManagement of the axilla in breast cancer has evolved rapidly following the implementation of sentinel lymph node biopsy (SLNB). Histological examination of the sentinel node allows accurate prediction of the overall stage of the axilla in 97% of patients [1-5]. Following SLNB, approximately 25-30% of patients will be identified as having a positive biopsy [3,6,7]. Current guidance from the American Joint Committee on Cancer (A]CC) [8] classifies axillary lymph node tumour deposits from a breast primary as macro metastasis, micro metastasis or isolated tumour cells (ITC). ITCs are single cells or small clusters of cells no greater than 0.2 mm in largest dimension, in the presence of which the node is classified as negative. AJCC staging distinguishes between ITC-positive [pNO (i+)] and ITC-negative [pN0(i-)] nodes; however, in the absence of proven benefit of intervention for ITC, current guidelines suggest equivalent management of these two groups [8,9]. Metastasis within a sentinel lymph node (SLN) is, conventionally, an indication for axillary clearance. Increased early breast cancer detection, more rigorous sectioning protocols and use of techniques such as immunological staining have increased the frequency with which micro metastasis and ITC are identified in the absence of concomitant macrometastatic disease. Published guidelines currently suggest treating axillae with sentinel nodes positive for micro metastasis but not in cases with ITC alone [9]. Despite this, significant variation in practice still exists; some groups advocate surgical management whenever tumour material within the sentinel node is identified, regardless of size. Others suggest selective avoidance of completion axillary lymph node dissection (cALND) following identification of micrometastatic disease in low-risk patients [10]. This paper reviews the evidence for performing axillary lymph node dissection (ALND), the reported incidence of sentinel and associated non-sentinel lymph node metastasis, the methods employed in prediction of non-sentinel lymph node (NSLN) metastasis and whether alternative treatment strategies following positive SLNB might rationalise current surgical management. <br/
The role of the lymph node in the establishment of an adaptive immune response to vaccination
No full textFollicular T-helper (TFH) cells are a subpopulation of CD4+ lymphocytes, which within germinal centres, determine differentiation of B-cells into memory cells and antibody-secreting plasmacytes. TFH are therefore critical players in vaccine-induced immunity. Study of TFH has been limited, as they are thought to be tissue resident cells, which do not normally re-circulate. While accessing blood is straightforward, access to lymph node tissue responding to vaccine is very limited. Therefore data on functions of tissue-resident human TFH cells remains sparse.This thesis details establishment of an ethically approved peri-surgical window of opportunity study and development of novel tissue processing techniques and laboratory assays designed to overcome this hurdle. I randomized 42 consenting breast cancer patients due to undergo sentinel lymph node biopsy to be vaccinated with combined tetanus/diphtheria/polio vaccine ipsilateraly, contralateraly or not at all prior to surgery. A vaccine draining, non-sentinel node was studied in the context of vaccine-specific antibody and circulating lymphocyte response over the seven weeks following vaccination.Only lymph nodes draining the ipsilateral vaccine site were enriched for two CD4+derived populations; TFH (CD45RO+CXCR5+ICOS+PD1+) and pre-TFH (CD45RO+CXCR5+ICOS+PD1-). In blood, transient increases in absolute numbers of these same populations were observed one week following vaccination (mean-fold-increase: TFH = 6.3; P = 0.002. Pre-TFH = 4.0; P=0.002). In contrast a related population (CD45RO+CXCR5+ICOS-PD1+) showed no enrichment within vaccine-draining nodes or changes in circulating numbers post-vaccine.Total IgG, IgM and IgG1-4 isotype immunoglobulin vaccine response was assessed. Response correlated with predominant cell-type increase in blood: CD45RO+CXCR5+ICOS+PD1- were prevalent in slow-responders, correlating with increases in immunoglobulin-switched plasmablasts (r = 0.90; 95%CI 0.74-0.97. P<0.0001), whereas CD45RO+CXCR5+ICOS+PD1+ were prominent in fast-responders, associated with increasing unswitched plasmablasts (r = 0.79; 95%CI 0.51-0.90. P<0.0001) and plasma cells (r = 0.57; 95%CI 0.17-0.81. P = 0.007). Dichotomisation of response according TFH sub-population tallies with measurable B-cell antibody and blast changes following vaccination. This possibly reflects memory state, suggesting different roles of TFH and pre-TFH in primary and secondary responses. Further study of the function of TFH in lymphoid tissue-should focus on these two dynamic populations
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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