1,720,959 research outputs found
Involvement Of Mitochondria In Diclofenac – And Ibuprofen- Induced Hepatotoxicity
Get PDFDiclofenac and ibuprofen are commonly used non-steroidal anti-inflammatory drugs
(NSAIDs) in the treatment of rheumatic diseases. However, these drugs are known
to cause hepatotoxicity in patients. Recent in vitro studies indicated that the
hepatotoxic effects of these NSAIDs are related to their ability to induce apoptosis
by targeting the mitochondria. This study was carried out to investigate and to
compare possible liver perturbation following diclofenac and ibuprofen
administration to rats. Male Sprague-Dawley rats (n=144) were treated with 3mg/kg,
5mg/kg and 1Omg/kg diclofenac and ibuprofen in normal saline, intraperitonealJy at
500~I/rat/day for 15 days. The control group was administered with saline in a
similar manner. Four rats from each group were euthanised every 3 consecutive
days. While 200mg/kg diclofenac and ibuprofen-treated rats (n=4) were euthanised
following a single dose 10 hours post-treatment. Upon euthanisation, the livers were
removed and cleaned with normal saline. A section across the right lobe was taken
and fixed in 10% (v/v %) formal saline and 4% (v/v) glutaraldehyde for light (H&E staining and TUNEL assay) and transmission electron microscopy, respectively. The
remaining samples were kept under -80°C for Western blotting analysis. The three
mg/kg diclofenac administered group at day 15 showed significant presence of
microvesicles and lymphocytic infiltration. The five mg/kg diclofenac-treated rats
revealed significant presence of microvesicles, lymphocytic and neutrophilic
infiltrations at day 15. Liver sections obtained from rats administered with 10 mg/kg
diclofenac showed significant presence of microvesic1es, mild lymphocytic and
neutrophilic infiltration and inflammation. The five mg/kg and 10mg/kg ibuprofeninjected
rats showed significant presence of microvesicles and mild focal
lymphocytic and neutrophilic infiltrations. These observations were mainly seen
around central veins (CVs). In TUNEL assay, 5mg/kg and IOmg/kg diclofenac and
IOmg/kg ibuprofen administered rats, showed apoptotic cells around the CVs at day
15. Ultrastructural study revealed swollen and ruptured mitochondrial membranes in
rats treated with 5mg/kg diclofenac, 10mg/kg diclofenac and 10mg/kg ibuprofen on
day 15. Western blotting analysis showed constant expression of cytochrome c in
liver homogenate and mitochondrial fraction on day 3,6,9, 12 and 15. However no
cytochrome c expression was detected in the cytosolic fraction. In 200 mg/kg
diclofenac and ibuprofen-treated rats, cytochrome c was detected in all 3 fractions;
homogenate, mitochondrial and cytosol. The expression of cytochrome c is higher
density in the cytosol from rats administered with diclofenac when compared to the
expression in cytosol from rats treated with ibuprofen. It can be concluded that
diclofenac is probably more potent in inducing changes in mitochondrial membrane
leading to apoptosis. However, at therapeutic dosage both drugs did not induce
prominent alteration in the mitochondria and the hepatocytes in general
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
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
Morphological alteration in mitochondria following diclofenac and ibuprofen administration.
Get PDFThis study was conducted to identify and to compare the mitochondrial morphological alterations in livers of rats treated with various doses of diclofenac and ibuprofen. Hundred and forty-four male Sprague Dawley rats were dosed with 3, 5 and 10 mg kg-1 diclofenac and ibuprofen in saline via intraperitoneal injection for 15 days. The control group was administered with saline in a similar manner. Four rats were euthanised every 3 days until day 15. While 200 mg kg-1 diclofenac and ibuprofen-treated rats (n = 4) were euthanized 10 h post-treatment. The livers were removed, cleaned and a section across the right lobe was taken and fixed in 4% (v/v) glutaraldehyde for electron microscopy analysis and the remaining samples were kept at -80°C for Western blot analysis. Five milligram per kilogram and 10 mg kg-1 diclofenac-administered rats for 15 days revealed the presence of enlarged mitochondria, irregular and ruptured mitochondrial membranes. While rats administered with 10 mg kg-1 ibuprofen also showed the presence of mitochondria with irregular membrane structure and ruptured membranes. Western blotting analysis of mitochondrial fractions revealed the expression of cytochrome c in all samples and complete absence of cytochrome c expression in the cytosolic fraction of all samples after day 15. Analysis in 200 mg kg -1 diclofenac and ibuprofen-treated groups, revealed expression of cytochrome c in both mitochondrial and cytosolic fractions. This observation indicates that both diclofenac and ibuprofen may alter the morphology of mitochondria, leading to cytochrome c release into the cytosol. Further studies needs to be conducted to investigate on the activity of the mitochondria following both treatments
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
