1,721,018 research outputs found
Skeletal Muscle Metabolism in Experimental Heart Failure
No full textWe studied
peripheral skeletal muscle metabolism in monocrotaline-treated rats. Two distinct groups emerged: a percentage
of the animals developed ventricular hypertrophy, with no signs of heart failure (compensated group), whilst
others, besides ventricular hypertrophy, developed the syndrome of congestive heart failure (CFH group). Oxidative
metabolism and redox cellular state were expressed in terms of creatine phosphate, purine (ATP, ADP and AMP)
and pyridine (NAD and NADH) nucleotides tissue content. Skeletal muscles with different metabolism were
studied: (a) Soleus (oxidative), (b) extensor digitorum longus (glycolytic) and tibialis anterior (oxidative and
glycolytic). The results showed that in CFH animals a decreased high-energy phosphates content occurs in the
soleus and extensor digitorum longus, but not in the tibialis anterior. In the soleus, ATP declined from 20.31±2.5
of control group to 9.55±0.61 lmol/g dry wt, while in the extensor digitorum longus ATP declined from
30.92±2.68 to 22.7±1.54 lmol/g dry wt. In both these muscles, a shift of NAD/NADH couple towards oxidation
was also observed (from 26.58±3.34 to 6.95±0.97 and from 18.88±3.43 to 10.57±1.61, respectively). These
alterations were more evident in the aerobic soleus muscle. On the contrary, no major changes occurred in
skeletal muscle metabolism of compensated animals. The results show that: (1) a decrease in muscle high-energy
phosphates occurs in CFH; (2) this is accompanied by a decrease of NAD/NADH couple suggesting an impairment
in oxygen utilization or availabilit
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
Effects of endotoxic shock on neuronal NOS and calcium transients in rat cardiac myocytes
No full textOBJECTIVE: The effects of endotoxic shock on transcriptional and translational pattern of nitric oxide synthase isoforms (NOSs) and cytoplasmic calcium were investigated. METHODS: Male SD rats injected with lipopolysaccharides or saline were sacrificed after 6 and 20 h. Cardiac myocytes were enzimatically isolated from the excised hearts and evaluated for: (1) expression of constitutive (e and n) and inducible (i) NOSs by RT-PCR; (2) NOSs protein levels by Western blot, enzymatic activities by a radioimmunometric assay and nitric oxide metabolites by spectrophotometry; (3) calcium transients by Indo-1 fluorescence. RESULTS: Increase in iNOS mRNA, and decrease in e and nNOS mRNAs were observed in cardiac myocytes isolated 6h after LPS injection with recovery to basal levels at 20 h. Significant down-regulation of e and nNOS protein levels (p < 0.01) and calcium-dependent activity (p < 0.05) were detected at 20 h. Serum TNF-alpha increased after 6 and 20 h (p < 0.05), whereas NO metabolites rose only after 20 h (p < 0.0001). The diastolic calcium increased 6 h from LPS injection (p < 0.0001) and remained significantly higher after 20 h. Calcium transients amplitude was not affected by LPS injection. CONCLUSIONS: Endotoxic shock stimulates iNOS and down-regulates expression of nNOS in purified cardiac myocytes, but endogenous NO production does not likely affect calcium transients
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
The Hip Functional Retrieval after Elective Surgery May Be Enhanced by Supplemented Essential Amino Acids.
No full textIt is not known whether postsurgery systemic inflammation and plasma amino acid abnormalities are still present during rehabilitation of individuals after elective hip arthroplasty (EHA). Sixty subjects (36 females; age 66.58 ± 8.37 years) were randomized to receive 14-day oral EAAs (8 g/day) or a placebo (maltodextrin). At admission to and discharge from the rehabilitation center, serum C-reactive protein (CRP) and venous plasma amino acid concentrations were determined. Post-EHA hip function was evaluated by Harris hip score (HHS) test. Ten matched healthy subjects served as controls. At baseline, all patients had high CRP levels, considerable reduction in several amino acids, and severely reduced hip function (HHS 40.78 ± 2.70 scores). After treatment, inflammation decreased both in the EAA group and in the placebo group. Only EAA patients significantly improved their levels of glycine, alanine, tyrosine, and total amino acids. In addition, they enhanced the rate of hip function recovery (HHS) (from baseline 41.8 ± 1.15 to 76.37 ± 6.6 versus baseline 39.78 ± 4.89 to 70.0 ± 7.1 in placebo one; p = 0.006). The study documents the persistence of inflammation and plasma amino acid abnormalities in post-EHA rehabilitation phase. EAAs enhance hip function retrieval and improve plasma amino acid abnormalities
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
- …
