247 research outputs found

    Motility-related protein-1 (MRP-1/CD9) expression can predict disease-free survival in patients with squamous cell carcinoma of the head and neck

    Get PDF
    CD9 is a transmembrane protein that has been implicated in cell adhesion, motility and proliferation, and numerous studies have demonstrated the prognostic value of its expression in different solid tumours. The purpose of this study is to determine the predictive value of CD9 in squamous cell carcinoma (SCC) of the head and neck. A total of 153 cases were examined for CD9 expression using immunohistochemistry applied on formalin-fixed, paraffin-embedded tissue. Cases were stratified in two categories depending on CD9 expression, as positive (>/=50% positive cells) or reduced (<50%). In all, 108 cases were positive for CD9 (85 cases with membranous, and 23 with both membranous and cytoplasmic staining) and 45 reduced expression. Reduced CD9 expression was significantly associated with high grade (P=0.0007) and lower disease-free survival (DFS) (P=0.017). The latter retained its significance in the multivariate analysis. When the 23 cases with both membranous and cytoplasmic patterns were studied as a separate subgroup, there were significant associations between CD9 expression and tumour grade (P=0.025) (95% CI 11-68), tumour stage (P=0.08) (95% CI 3.5-86) and the occurrence of any failure (P=0.083) (95% CI -1.7-57). Immunohistochemical CD9 expression proved to be an independent prognostic factor in SCC of the head and neck, and it may detect patients at a high risk of recurrence. In addition, the cytoplasmic pattern seems to have an even more significant value. However, this finding is limited to the small number of cases with this pattern

    Highly efficient catalysis of the Kemp elimination in the cavity of a cubic coordination cage.

    Get PDF
    The hollow cavities of coordination cages can provide an environment for enzyme-like catalytic reactions of small-molecule guests. Here, we report a new example (catalysis of the Kemp elimination reaction of benzisoxazole with hydroxide to form 2-cyanophenolate) in the cavity of a water-soluble M8L12 coordination cage, with two features of particular interest. First, the rate enhancement is among the largest observed to date: at pD 8.5, the value of kcat/kuncat is 2 × 10(5), due to the accumulation of a high concentration of partially desolvated hydroxide ions around the bound guest arising from ion-pairing with the 16+ cage. Second, the catalysis is based on two orthogonal interactions: (1) hydrophobic binding of benzisoxazole in the cavity and (2) polar binding of hydroxide ions to sites on the cage surface, both of which were established by competition experiments

    The Early Royal Society and Visual Culture

    Get PDF
    Recent studies have fruitfully examined the intersection between early modern science and visual culture by elucidating the functions of images in shaping and disseminating scientific knowledge. Given its rich archival sources, it is possible to extend this line of research in the case of the Royal Society to an examination of attitudes towards images as artefacts –manufactured objects worth commissioning, collecting and studying. Drawing on existing scholarship and material from the Royal Society Archives, I discuss Fellows’ interests in prints, drawings, varnishes, colorants, images made out of unusual materials, and methods of identifying the painter from a painting. Knowledge of production processes of images was important to members of the Royal Society, not only as connoisseurs and collectors, but also as those interested in a Baconian mastery of material processes, including a “history of trades”. Their antiquarian interests led to discussion of painters’ styles, and they gradually developed a visual memorial to an institution through portraits and other visual records.AH/M001938/1 (AHRC

    Long term survival following the detection of circulating tumour cells in head and neck squamous cell carcinoma

    Get PDF
    Background Techniques for detecting circulating tumor cells in the peripheral blood of patients with head and neck cancers may identify individuals likely to benefit from early systemic treatment. Methods Reconstruction experiments were used to optimise immunomagnetic enrichment and RT-PCR detection of circulating tumor cells using four markers (ELF3, CK19, EGFR and EphB4). This method was then tested in a pilot study using samples from 16 patients with advanced head and neck carcinomas. Results Seven patients were positive for circulating tumour cells both prior to and after surgery, 4 patients were positive prior to but not after surgery, 3 patients were positive after but not prior to surgery and 2 patients were negative. Two patients tested positive for circulating cells but there was no other evidence of tumor spread. Given this patient cohort had mostly advanced disease, as expected the detection of circulating tumour cells was not associated with significant differences in overall or disease free survival. Conclusion For the first time, we show that almost all patients with advanced head and neck cancers have circulating cells at the time of surgery. The clinical application of techniques for detection of spreading disease, such as the immunomagnetic enrichment RT-PCR analysis used in this study, should be explored further

    Monsters, Laws of Nature, and Teleology in Late Scholastic Textbooks

    Get PDF
    In the period of emergence of early modern science, ‘monsters’ or individuals with physical congenital anomalies were considered as rare events which required special explanations entailing assumptions about the laws of nature. This concern with monsters was shared by representatives of the new science and Late Scholastic authors of university textbooks. This paper will reconstruct the main theses of the treatment of monsters in Late Scholastic textbooks, by focusing on the question as to how their accounts conceived nature’s regularity and teleology. It shows that they developed a naturalistic teratology in which, in contrast to the naturalistic explanations usually offered by the new science, finality was at central stage. This general point does not impede our noticing that some authors were closer to the views emerging in the Scientific Revolution insofar as they conceived nature as relatively autonomous from God and gave a relevant place to efficient secondary causation. In this connection, this paper suggests that the concept of the laws of nature developed by the new science –as exception-less regularities—transferred to nature’s regularity the ‘strong’ character that Late Scholasticism attributed to finality and that the decline of the Late Scholastic view of finality played as an important concomitant factor permitting the transformation of the concept of laws of nature

    Exciting new advances in oral cancer diagnosis: avenues to early detection

    Get PDF
    The prognosis for patients with oral squamous cell carcinoma remains poor in spite of advances in therapy of many other malignancies. Early diagnosis and treatment remains the key to improved patient survival. Because the scalpel biopsy for diagnosis is invasive and has potential morbidity, it is reserved for evaluating highly suspicious lesions and not for the majority of oral lesions which are clinically not suspicious. Furthermore, scalpel biopsy has significant interobserver and intraobserver variability in the histologic diagnosis of dysplasia. There is an urgent need to devise critical diagnostic tools for early detection of oral dysplasia and malignancy that are practical, noninvasive and can be easily performed in an out-patient set-up. Diagnostic tests for early detection include brush biopsy, toluidine blue staining, autofluorescence, salivary proteomics, DNA analysis, biomarkers and spectroscopy. This state of the art review critically examines these tests and assesses their value in identifying oral squamous cell carcinoma and its precursor lesions

    Arterial pressure changes monitoring with a new precordial noninvasive sensor

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Recently, a cutaneous force-frequency relation recording system based on first heart sound amplitude vibrations has been validated. A further application is the assessment of Second Heart Sound (S2) amplitude variations at increasing heart rates. The aim of this study was to assess the relationship between second heart sound amplitude variations at increasing heart rates and hemodynamic changes.</p> <p>Methods</p> <p>The transcutaneous force sensor was positioned in the precordial region in 146 consecutive patients referred for exercise (n = 99), dipyridamole (n = 41), or pacing stress (n = 6). The curve of S2 peak amplitude variation as a function of heart rate was computed as the increment with respect to the resting value.</p> <p>Results</p> <p>A consistent S2 signal was obtained in all patients. Baseline S2 was 7.2 ± 3.3 m<it>g</it>, increasing to 12.7 ± 7.7 m<it>g </it>at peak stress. S2 percentage increase was + 133 ± 104% in the 99 exercise, + 2 ± 22% in the 41 dipyridamole, and + 31 ± 27% in the 6 pacing patients (p < 0.05). Significant determinants of S2 amplitude were blood pressure, heart rate, and cardiac index with best correlation (R = .57) for mean pressure.</p> <p>Conclusion</p> <p>S2 recording quantitatively documents systemic pressure changes.</p

    Insertion and translocation of proteins into and through membranes

    Get PDF
    AbstractIn prokaryotic and eukaryotic organisms proteins are efficiently sorted to reach their final destinations in a whole range of subcellular compartments. Targeting is mediated by Hydrophobie signal sequences or hydrophilic targeting sequences depending upon the compartment, these sequences being often processed. Proteins cannot be translocated through a membrane in a tightly folded stage, they must have a loose conformation, the so-called ‘translocation competent state’, which is usually kept through interactions with chaperones. In addition to these cytosolic receptor-like components, receptors are also present on the target membranes. Depending upon the organelles and organisms, two different energy sources have been identified, energy rich phosphate bonds (ATP and GTP) and a potential across the target membrane. Besides the signal peptides various classes of signals have been identified to account for topologies of membrane proteins. Protein secretion in bacterial organisms has been extensively studied. Various classes of proteins use different strategies some of these may also be used in eukaryotic cells
    corecore