1,720,961 research outputs found
Favorable Vascular Actions of Angiotensin-(1-7) in Human Obesity
No full textObese patients have vascular dysfunction related to impaired insulin-stimulated vasodilation and increased endothelin-1-mediated vasoconstriction. In contrast to the harmful vascular actions of angiotensin (Ang) II, the angiotensinconverting enzyme 2 product Ang-(1-7) has shown to exert cardiovascular and metabolic benefits in experimental models through stimulation of the Mas receptor. We, therefore, examined the effects of exogenous Ang-(1-7) on vasodilator tone and endothelin-1-dependent vasoconstriction in obese patients. Intra-arterial infusion of Ang-(1-7) (10 nmol/min) resulted in significant increase in unstimulated forearm flow (P=0.03), an effect that was not affected by the Mas receptor antagonist A779 (10 nmol/min; P>0.05). In the absence of hyperinsulinemia, however, forearm flow responses to graded doses of acetylcholine and sodium nitroprusside were not different during Ang-(1-7) administration compared with saline (both P>0.05). During infusion of regular insulin (0.15 mU/kg per minute), by contrast, endothelium-dependent vasodilator response to acetylcholine was significantly enhanced by Ang-(1-7) (P=0.04 versus saline), whereas endothelium-independent response to sodium nitroprusside was not modified (P=0.91). Finally, Ang-(1-7) decreased the vasodilator response to endothelin A receptor blockade (BQ-123; 10 nmol/min) compared with saline (6±1% versus 93±17%; P<0.001); nitric oxide inhibition by l-N-monomethylarginine (4 uÎ1⁄4mol/min) during concurrent endothelin A antagonism resulted in similar vasoconstriction in the absence or presence of Ang-(1-7 Ang-(1-7) (P=0.69). Our findings indicate that in obese patients Ang-(1-7) has favorable effects not only to improve insulin-stimulated endotheliumdependent vasodilation but also to blunt endothelin-1-dependent vasoconstrictor tone. These findings provide support for targeting Ang-(1-7) to counteract the hemodynamic abnormalities of human obesity
Polyvinylidene Fluoride Mesh (PVDF, DynaMesh®-IPOM) in The Laparoscopic Treatment of Incisional Hernia: A Prospective Comparative Trial versus Gore® ePTFE DUALMESH® Plus.
No full textBACKGROUND:
Laparoscopic approach is now generally accepted for the treatment of incisional hernia. The ideal mesh is still to be found. The aim of this study is to compare the well-known Gore® DUALMESH® Plus (WL Gore & Associates, Flagstaff, AZ) to a new prosthesis, the DynaMesh®-IPOM (FEG Textiltechnik GmbH, Aachen, Germany), to clinically verify its potential benefits in the laparoscopic treatment of incisional hernia.
MATERIALS AND METHODS:
Comparing the results of the laparoscopic treatment of two groups of patients affected by incisional hernia using Gore® DUALMESH® Plus and DynaMesh®-IPOM.
RESULTS:
There were 45 females and 31 males, with age variable from 21 to 84 years of age. The two groups were well matched for age (median age 60 years for group A and 57.6 years for group B-p=0.44) and sex (28F and 17M group A and 13 F and 18 M group B-p=0.008), while median BMI resulted slightly higher in group B (26.12 group A and 29.74 group B-p=0.001). The median size of the defect was similar in the two groups (87.5 mm group A and 83.4 mm for group B-p=0.83), while the median operating time was slightly longer in group A (77 min group A and 67 min group B-p=0.44). No difference in the length of hospital stay was evidenced between the two groups (3.19 days for group A and 3 days for group B-p=0.74). Time to return to physical activity was similar between the two groups (13.46 days for group A and 12.7 days for group B-p=0.32). Minor complications occurred in 15 cases (19.7%): seromas (7 cases), prolonged ileus (6 cases), and hemoperitoneum (2 cases), without significant difference in the incidence of such complications in the two groups. Five recurrences (6.5% of cases) occurred. No differences in the recurrence rate was noted between the two groups (3 cases/7% for group A and 2 cases/6% for group B-p=00.7).
CONCLUSIONS:
DynaMesh®-IPOM proved to be a safe and effective mesh for the laparoscopic repair of incisional hernia even when compared to DUALMESH® Plus
Short-term effects of laparoscopic adjustable gastric banding versus Roux-en-Y gastric bypass
No full textOBJECTIVE Bariatric surgery has been shown to have important long-term metabolic effects resulting in enhanced insulin sensitivity and improved glucose tolerance in patients with type 2 diabetes. The contribution of reduced caloric intake to these beneficial effects of surgery remains unclear. The aim of this study was to compare the shortterm effects (1 week) of bariatric surgical procedures with a very low caloric intake (VLCI) on insulin sensitivity (IS) and insulin secretion (ISR) in nondiabetic obese subjects. RESEARCH DESIGN AND METHODS Twenty obese patients without diabetes (BMI 44.260.7 kg/m2) were admitted to the clinic for 1 week. At baseline and 1 week after VLCI (600 kcal/day), subjects received a hyperinsulinemic-euglycemic clamp with tracer infusion to quantify endogenous glucose production (EGP), lipolysis (rate of appearance of glycerol [RaGlycerol]), peripheral insulin sensitivity (insulin-stimulated glucose disposal [M value] divided by the steady-state plasma insulin concentration [M/I]), hepatic insulin sensitivity (Hep-IS [= 1/(EGP · insulin)]), and adipose insulin sensitivity (Adipo-IS [= 1/(RaGlycerol · insulin)]). An intravenous glucose bolus was administered at the end of the insulin clamp to measure ISR and β-cell function (disposition index [DI]). Approximately 3 months later, patients were admitted for laparoscopic adjustable gastric banding (LAGB) (n = 10) or Roux-en-Y gastric bypass (RYGB) (n = 10), and were restudied 1 week after surgery under the same caloric regimen (600 kcal/day). RESULTS After 1 week of VLCI, patients lost 2.1 kg without significant changes in Hep-IS, Adipo-IS, M/I, or DI. RYGB and LAGB led to greater weight loss (5.5 and 5.2 kg, respectively) and to significant improvement in Hep-IS, EGP, and lipolysis. Only RYGB improved Adipo-IS and M/I. No change in ISR or DI was observed in either surgical group. CONCLUSIONS Bariatric surgery improves IS within 1 week. These metabolic effects were independent of caloric intake and more pronounced after RYGB compared with LAGB
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
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
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
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