169,766 research outputs found
Arachidonic acid mediates calcium influx induced by basic fibroblast growth factor in Balb-c 3T3 fibroblasts
No full textThe inward current activated by bradikinin in Balb-c 3T3 fibroblasts and its relationship to fibroblast growth factor activated currents
No full textHepatitis C virus infection and clonal B-cell expansion
No full textThe striking association between hepatitis C virus (HCV) infection and the so-called "essential" mixed cryoglobulinemia (MC) has led to the hypothesis that HCV plays a major role in the production of cryoglobulins. Analysis of soluble and cryoprecipitable immune complexes shows that the hepatitis C virion is bound to IgM bearing the WA cross-idiotype (XId). The production of WA XId IgM seems to be the result of chronic stimulation by HCV of a population of WA XId + CD5 + B cells. It is possible that the reactivity of WA XId IgM does not initially include rheumatoid factor (RF) activity, which may be acquired secondarily from mutational events accompanying a probably T-cell independent B cell proliferation. Type II MC is a benign proliferation that progresses to malignancy in a minority of patients. This is consistent with the concept that malignancy progression involves the accumulation of multiple mutations of proto-oncogenes and tumor suppressor genes that are facilitated by chronic antigenic stimulation. The recent demonstration of HCV in hyperplastic reactive lymphoadenopathy and in the neoplastic lymph nodes of patients with MC strengthens the putative role played by HCV in lymphomagenesis. A fuller understanding of the virus-related mechanisms of lymphoproliferation in MC patients would contribute significantly to the development of therapeutic strategies
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Calcium signals induced by extracellular application of NAADP in developing neurons and glial cells
No full textMitomycin C in highly myopic eyes - Author reply
No full textOphthalmology. 2005 Feb;112(2):208-18; discussion 219.
Mitomycin C modulation of corneal wound healing after photorefractive keratectomy in highly myopic eyes.
Gambato C, Ghirlando A, Moretto E, Busato F, Midena E.
SourceRefractive Surgery Service and Antimetabolite Therapy Research Unit, Department of Ophthalmology, University of Padova, Padova, Italy.
Abstract
PURPOSE: To evaluate the role of topical mitomycin C in corneal wound healing (CWH) after photorefractive keratectomy (PRK) in highly myopic eyes.
DESIGN: Prospective, double-masked, randomized clinical trial.
PARTICIPANTS: Seventy-two eyes of 36 patients affected by high (>7 diopters) myopia.
METHODS: In each patient, one eye was randomly assigned to PRK with intraoperative topical 0.02% mitomycin C application, and the fellow eye was treated with a placebo. Postoperatively, mitomycin C-treated eyes received artificial tears (3 times daily, tapered in 3 months), whereas the fellow eye was treated with fluorometholone sodium 2% and artificial tears (3 times daily, tapered in 3 months).
MAIN OUTCOME MEASURES: Uncorrected visual acuity (UCVA) and best-corrected visual acuity (BCVA), contrast sensitivity, manifest refraction, and biomicroscopy. Contrast sensitivity was determined using the Pelli-Robson chart. Corneal confocal microscopy documented CWH.
RESULTS: Mean follow-up was 18 months (range, 12-36). No side effects or toxic effects were documented. At 12-month follow-up examination, UCVAs (logarithm of the minimum angle of resolution) were 0.4+/-0.48 and 0.5+/-0.53 (P = .03) in mitomycin C-treated eyes and corticosteroid-treated eyes, respectively. At 1 year, corneal haze developed in 20% of corticosteroid-treated eyes, versus 0% of mitomycin C-treated eyes. At 12, 24, and 36 months, corneal confocal microscopy showed activated keratocytes and extracellular matrix significantly more evident in untreated eyes (Ps = 0.004, 0.024, and 0.046, respectively).
CONCLUSION: Topical intraoperative application of 0.02% mitomycin C can reduce haze formation in highly myopic eyes undergoing PRK.
Comment in
Ophthalmology. 2006 Feb;113(2):357; author reply 357-8
Hydrophilic/hydrophobic features of TiO2 nanoparticles as a function of crystal phase, surface area and coating, in relation to their potential toxicity in peripheral nervous system
No full textImmunohistochemical detection of hepatitis C virus-related proteins in liver tissue
No full textOBJECTIVE:
Hepatitis C virus (HCV)-associated antigens (Ags) are hard to detect and poorly defined in liver tissue, and are of uncertain interpretation. The failure of immunohistochemistry in HCV infection may be due to the affinity of specific antisera, the levels of Ags in infected tissues, the labile and unstable expression of antigenic determinants, and the use of fixatives that may alter or destroy viral epitopes. Strategies to optimize all stages of tissue specimen processing have therefore been devised in the liver biopsies of patients with acute and chronic hepatitis, and those with hepatocellular carcinoma (HCC).
METHODS:
HCV-Ags were detected with a two-stage indirect immunostaining procedure on unfixed cryostat liver sections from 7 acute and 23 chronic HCV-infected patients, and from 4 patients with HCV-associated HCC. A mixture of monoclonal antibodies directed to structural and non-structural HCV-related proteins were used as the primary reagents.
RESULTS:
HCV-Ags in 50-70% of the hepatocytes were found in all seven acute hepatitis patients compared with < or = 20% hepatocytes (P < 0.05) in 10 out of 23 patients (43.5%) with chronic hepatitis. Immunoreactive signals appeared as diffuse or coarse granular deposits in the cytoplasm only. The nuclei were unstainable. No clear membranous pattern was found, although fine granular, submembranous accumulation in distinct areas of the cytoplasm was observed. In acute hepatitis, HCV-Ag positive hepatocytes were distributed in the lobules in direct relation to the areas of necrosis and inflammatory cell accumulation, whereas in chronic hepatitis the immunoreactive cells were not clearly related to the necrotic foci. HCV-Ag immunodeposits were demonstrated in all patients with HCC. The immunoreactive signal in neoplastic cells was primarily located in the cytoplasm and rarely in the nuclei. As compared with the non-neoplastic zones, neoplasia demonstrated a significantly higher specific signal.
CONCLUSIONS:
Immunohistology is a powerful tool for the identification of HCV-related proteins in liver tissue. Sensitivity was significantly enhanced by the use of fresh-frozen tissues, which presumably preserve their HCV antigen structure, and by a mixture of monoclonal antibodies directed against HCV-related proteins, possibly on account of the separate access of each probe to different target proteins. The demonstration of HCV infection in hepatocyte cytoplasm indicates that this is the primary site of HCV replication, while its presence in malignant cells suggests that the virus could be substantially involved in the pathogenesis of HCC
Dispelling the Myths Behind First-author Citation Counts
No full textWe 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
A Multi-Language Comparison of Influences on Author Verification using Character N-Grams
No full textWe create a new multi-language corpus for author verification based on Wikipedia talkpages, and evaluate the influence that differences in topic and time have on character n-gram author profiles. Topic alignment between two texts is found to increase author verification precision, and an authors writing style is found to change over time, but not more significantly after 3 years than after 1 year.Information ArchitectureWISElectrical Engineering, Mathematics and Computer Scienc
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