1,721,026 research outputs found
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
Efficacy of polycationic peptides in preventing vascular graft infection due to Staphylococcus epidermidis.
No full textA rat model was used to investigate the efficacy of two polycationic peptides, ranalexin and buforin II, in the prevention of vascular prosthetic graft infection due to methicillin-resistant Staphylococcus epidermidis with intermediate resistance to glycopeptides. The in vitro activity of the peptides was compared with those of vancomycin and teicoplanin by MIC determination and time-kill study. Moreover, the efficacy of collagen-sealed peptide-soaked Dacron was evaluated in a rat model of graft infection. Graft infections were established in the dorsal subcutaneous tissue of 120 adult male Wistar rats. The in vivo study included a control group, one contaminated group that did not receive any antibiotic prophylaxis and four contaminated groups that received an antibiotic-soaked graft. Experiments demonstrated that the activities of buforin II and ranalexin were greater than those of vancomycin and teicoplanin. Particularly, rats with buforin II-coated Dacron grafts showed no evidence of staphylococcal infection while, for the rats with ranalexin-, vancomycin- and teicoplanin-coated Dacron grafts, the quantitative graft cultures demonstrated bacterial growth (1.9 x 10(2) +/- 0.6 x 10(2) cfu/mL, 6. 2 x 103 +/- 1.9 x 10(3) cfu/mL and 5.1 x 10(4) +/- 4.8 x 10(3) cfu/mL, respectively). The study demonstrated that the use of peptide-soaked Dacron graft can result in significant bacterial growth inhibition and indicates that these compounds may be potentially useful in prosthetic surgery
Valore prognostico dell'indice Apache II nell'impiego routinario preoperatorio in chirurgia generale maggiore
No full textThe authors examined the prognostic value, in daily preoperative practice, of Apache II scoring system in 187 patients undergoing elective or emergency major general surgery, and compared it with those of more traditional classification systems, such as the American Society of Anesthesiologists (ASA) classification system and the Weighted Scale of Operartive Risk (WSOR). Logistic regression analysis and ROC (Receiver Operating Characteristic) curve analysis confirmed Apache II system to have good predictive value for mortality and morbidity; it was superior to the examined traditional classification systems in prediction of outcome after surgery (area under curve 0.89 for the Apache II index, 0.78 for the ASA classification system 0.79 for the WSOR). The Apache II score deprived of the age points (area under curve 0.98) showed the same prognostic power of the complete score (area under curve 0.89), so age alone was not a significant variable in our experience. If used in daily practice the preoperative Apache II score may be used by clinicians to evaluate before surgery the risk of postoperative morbidity and death in major general surgery
Cationic peptides combined with betalactams reduce mortality from peritonitis in experimental rat model.
No full textThe efficacy of cationic peptides combined with betalactams was investigated in a peritonitis rat model. Intraabdominal sepsis was induced in adult Wistar rats via cecal ligation and single puncture. The study included eight drug-treated groups: each of them received intravenous polymyxin-E (1 mg/kg), buforin II (1 mg/kg), imipenem (20 mg/kg), amoxicillin-clavulanate (50 mg/kg), polymyxin-E (1 mg/kg) plus imipenem (20 mg/kg), or amoxicillin-clavulanate (50 mg/kg), and buforin II (1 mg/kg) plus imipenem (20 mg/kg), or amoxicillin-clavulanate (50 mg/kg). The study included an untreated control group that received intravenous isotonic sodium chloride solution. All compounds significantly reduced the lethality and the number of bacteria in abdominal fluid compared with saline treatment. Among compounds, imipenem showed the highest antimicrobial activity, while buforin II produced the highest reduction in plasma endotoxin and TNF-alpha levels. Overall, buforin II and imipenem association were the most effective therapeutic approach. Data presented here suggest the potential advantages of combining antimicrobial agents and compounds able to neutralize the biological effect of the endotoxin
[Vascular graft infection by Staphylococcus epidermidis: efficacy of various perioperative prophylaxis protocols in an animal model].
No full textA rat model was used to investigate the efficacy of levofloxacin, cefazolin and teicoplanin in the prevention of vascular prosthetic graft infection. Graft infections were established in the subcutaneous tissue of 300 male Wistar rats by implantation of Dacron prostheses followed by topical inoculation with methicillin-susceptible and methicillin-resistant S. epidermidis. The study included a group without contamination, two contaminated groups without prophylaxis, two contaminated groups with intraperitoneal levofloxacin prophylaxis (10 mg/kg), two contaminated groups with intraperitoneal cefazolin prophylaxis (30 mg/kg), two contaminated groups with intraperitoneal teicoplanin prophylaxis (10 mg/kg) and six contaminated groups with rifampin-soaked graft and intraperitoneal levofloxacin, cefazolin or te- icoplanin prophylaxis. The grafts were removed after 7 days and evaluated by quantitative culture. The efficacy of levofloxacin against the methicillin- susceptible strain did not differ from that of cefazolin or teicoplanin. Levofloxacin showed slight less efficacy than teicoplanin against the methicillin-resistant strain. The levofloxacin-rifampin combination proved to be similarly effective to the rifampin-teicoplanin combination and more effective than the rifampin-cefazolin combination against both strains. The rifampin-levofloxacin combination may be useful for the prevention of late-appearing vascular graft infections caused by S. epidermidis because it takes advantage of the good anti-staphylococcal activity of both drugs
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
Effect of mono-dose intraperitoneal cecropins in experimental septic shock
No full textOBJECTIVE:
To investigate the efficacy of three cecropins, cecropin A, cecropin B, and cecropin P1, in preventing lethality in a rat model of septic shock.
DESIGN:
Prospective, randomized, controlled animal study.
SETTING:
Research laboratory in a university hospital.
SUBJECTS:
Adult male Wistar rats.
INTERVENTIONS:
Rats were given an intraperitoneal injection of 2 x 10(10) colony forming units of Escherichia coli, with the exception of the uninfected control group (C0). Animals were randomized to receive, immediately after bacterial challenge, intraperitoneally isotonic sodium chloride solution (untreated control group C1), 1 mg/kg cecropin A (group 2), 1 mg/kg cecropin B (group 3), 1 mg/kg cecropin P1 (group 4), 20 mg/kg imipenem (group 5), or 60 mg/kg piperacillin (group 6). Each group included 15 animals.
MEASUREMENTS AND MAIN RESULTS:
We measured bacterial growth (quantitative agar culture) in abdominal exudate and plasma, endotoxin and tumor necrosis factor-alpha concentration in plasma, and mortality. Results were evaluated at 48 hrs after inoculation. Cecropins, piperacillin, and imipenem significantly reduced the lethality and the number of E. coli in abdominal fluid compared with saline treatment. In addition, cecropin B significantly decreased the lethality compared with piperacillin treatment. Finally, only cecropins significantly reduced plasma endotoxin concentration.
CONCLUSIONS:
Mono-dose cecropin treatment prevents bacterial growth, endotoxemia, and mortality in rats with septic shock. Cecropin B was the most effective compound in reducing all variables measured
Glyoxalase II and glutathione levels in rat liver mitochondria during cold storage in Euro-Collins and University of Wisconsin solutions
No full textTherapeutic efficacy of the polymyxin-like peptide ranalexin in an experimental model of endotoxemia.
No full textBACKGROUND:
A rat model was used to investigate the efficacy of a polycationic peptide, the polymyxin-like ranalexin, in the prevention of lethality in a rat model of septic shock. The effect of ranalexin was compared with those of polymyxin B and imipenem.
METHODS:
Adult male Wistar rats (weight range: 250-300 g) were used for all the experiments. The study included five groups: an uninfected control group C(0), an untreated control group C(1), and three drug-treated groups that received 1 mg/kg ranalexin (group 2), 20 mg/kg imipenem (group 3), and 3 mg/kg polymyxin B (group 4). Rats, with the exception of the uninfected control group (C(0)), were given an intraperitoneal injection of 2 x 10(10) colony-forming units of Escherichia coli. Each group included 15 animals. Bacterial growth in abdominal exudate and plasma; endotoxin and tumor necrosis factor alpha (TNF-alpha) concentrations in plasma, and mortality were evaluated.
RESULTS:
Results were evaluated 48 h after inoculation. Ranalexin, imipenem, and polymyxin B significantly reduced the lethality (survival was 93.3, 80.0, and 93.3%, respectively) and the growth of E. coli both in abdominal fluid and plasma compared with saline treatment. Ranalexin showed higher antimicrobial activity than polymyxin B and imipenem and, at the same time, exhibited an antiendotoxin activity similar to that of polymyxin B (< or =0.015 EU/mL). Finally, ranalexin and polymyxin B significantly reduced plasma TNF-alpha levels (< or =4 pg/mL).
CONCLUSION:
Monodose ranalexin treatment prevents bacterial growth, endotoxemia, and mortality in rats with septic shock
- …
