1,720,957 research outputs found
Ruptured Achilles tendons show increased lectin stainability.
No full textPURPOSE:
To ascertain whether lectins could be a useful tool for investigation of the extracellular matrix of degenerated and normal tendons.
METHODS:
Hematoxylin-eosin-stained slides were assessed blindly using a semiquantitative grading scale for fiber structure, fiber arrangement, rounding of the nuclei, regional variations in cellularity, increased vascularity, decreased collagen stainability, hyalinization, and glycosaminoglycan, with a pathology score giving up to three marks per each of the above variables, with 0 being normal and 3 being maximally abnormal. For lectin staining with Aleuria aurantia, Canavalia ensiformis, Galanthus nivalis, Phaseolus vulgaris, Arachis hypogea, Sambucus nigra, and Triticum vulgaris, assessment of staining on a scale from 0 (no staining) to 5 (strong staining) was performed blindly.
RESULTS:
The mean pathology sum score of ruptured tendons (N = 14; average age 46.5 yr, range 29-61) was significantly greater than the mean pathology score of the control tendons of Achilles tendons from individuals with no known tendon pathology (N = 16; average age 62.5 yr, range 49-73) (pathology score: 18.5 +/- 3.2 vs 6.1 +/- 2.3). Four of the seven lectins used exhibited significantly positive results.
CONCLUSIONS:
Ruptured tendons were histologically significantly more degenerated than control tendons. Ruptured tendons showed different lectin staining properties than nonruptured ones. This difference may have resulted from posttranslational changes in the extracellular matrix producing alterations in the biochemistry of the tendon, which might interfer
Tenocytes from ruptured and tendinopathic achilles tendons produce greater quantities of type III collagen than tenocytes from normal achilles tendons. An in vitro model of human tendon healing.
No full textType I collagen is the main collagen in tendons; type III collagen is present in small amounts. Ruptured Achilles tendons contain a significantly greater proportion of type Ill collagen, which predisposes them to rupture. We used an in vitro model to determine whether tenocytes from Achilles tendons that were ruptured (N = 22), nonruptured (N = 7), tendinopathic (N = 12), and fetal (N = 8) show different behavior. Samples of Achilles tendon were digested with collagenase and the released tenocytes were collected. Primary tenocyte cultures were established and subsequently cultured onto glass coverslips. Once a confluent monolayer was obtained, the cell populations were "wounded" by scraping a pipette tip along the surface. The cultures were further incubated for either 1, 4, 8, 12, 16, or 24 hours, and production of types I and II collagen was assessed by immunostaining. In cultures from ruptured and tendinopathic tendons, there was increased production of type Ill collagen. Athletic participation places excess stress on the Achilles tendon, which could potentially lead to areas of microtrauma within the tendon. These areas may heal by the production of type III collagen, which is an abnormal healing response. Accumulation of such episodes of microtrauma could resuit in a critical point where the resistance of the tissue to tensile forces is compromised and tendon rupture occurs
ABO blood groups and achilles tendon rupture in the Grampian Region of Scotland.
No full textOBJECTIVE:
To test whether the association between blood groups and Achilles tendon rupture (ATR) reported in some Scandinavian countries and in Hungary was present in our region.
METHODS:
We studied 78 patients treated at Aberdeen Royal Infirmary from 1990 to 1996, and compared their distribution of ABO blood groups with that found in 24.501 blood donors typed at the Blood Transfusion Centre during the same period.
RESULTS:
Overall, 47 of 78 (60%) of patients with an Achilles tendon rupture belonged to blood group O, compared with 51% of the population as a whole. Only 22 (28%) of the Achilles tendon rupture patients belonged to blood group A, whereas 35% of the general population were members of this group (NS). The A/O ratio was 0.47 for the tendon rupture patients, compared with 0.68 for the general population (NS).
CONCLUSIONS:
We could not demonstrate any significant association between the proportions of ABO blood groups and ATR in the Grampian Region of Scotland. The findings in other studies could be due to peculiarities in the distribution of the ABO groups in genetically segregated populations
Changing incidence of Achilles tendon rupture in Scotland: a 15-year study.
No full textOBJECTIVE:
To determine the incidence of Achilles tendon rupture in Scotland from 1980 to 1995.
DESIGN:
Retrospective analysis of prospectively collected data.
SETTING:
Data were obtained from the National Health Service Information and Statistics Division and analyzed in terms of age- and gender-specific incidence rates and time trends by age group.
PARTICIPANTS:
A total of 4,201 patients with Achilles tendon ruptures occurring during the study period.
MAIN OUTCOME MEASURES:
Calculation of incidence and of seasonality.
RESULTS:
The overall incidence of Achilles tendon rupture increased from 4.7/100,000 in 1981 to 6/100,000 in 1994, with a peak in 1986. In men, the incidence rose from 6.3/100,000 to 7.3/100,000. In women, the increase in incidence was more pronounced, from 3/100,000 to 4.7/100,000. In men, peak incidence rate occurred in the 30- to 39-year age group, whereas in women, the peak age-specific incidence occurred in those aged 80 years and older, with a steady increase after age 60. There was no evidence of a seasonality effect in the rate of occurrence of Achilles tendon rupture. A bimodal distribution of age at time of Achilles tendon rupture was noted.
CONCLUSION:
There was a significant increase in the incidence of Achilles tendon rupture during the period from 1980 to 1995. This reflects the increased incidence of the injury noted in other Northern European countries
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
- …
