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81.

Background

Seaweed polysaccharides are highly active natural substances having valuable applications. The present study was conducted to characterize the physico-chemical properties of sulphated polysaccharides from three Mediterranean brown seaweeds (Cystoseira sedoides, Cystoseira compressa and Cystoseira crinita) and to evaluate their anti-radical, anti-inflammatory and gastroprotective activities.

Methods

The different rates of neutral sugars, uronic acids, L-fucose and sulphate content were determined by colorimetric techniques. The different macromolecular characteristics of isolated fucoidans were identified by size exclusion chromatography equipped with a triple detection: multiangle light scattering, viscometer and differential refractive index detectors, (SEC/MALS/VD/DRI). Anti-inflammatory activity was evaluated, using the carrageenan-induced rat paw edema test in comparison to the references drugs Acetylsalicylate of Lysine and Diclofenac. The gastroprotective activity was determined using HCl/EtOH induced gastric ulcers in rats and to examine the antioxidant effect of fucoidans in the three species, the free radical scavenging activity was determined using 1,1-diphenyl-2-picrylhydrazyl.

Results

The pharmacological evaluation of the isolated fucoidans for their anti-inflammatory, and their gastroprotective effect established that these products from C. sedoides, C. compressa and C. crinita exhibited a significant anti-inflammatory activity at a dose of 50 mg/kg, i.p; the percentages of inhibition of the oedema were 51%, 57% and 58% respectively. And, at the same dose, these fucoidans from C. sedoides and C. compressa showed a significant decrease of the intensity of gastric mucosal damages compared to a control group by 68%, whereas, the fucoidan from C. crinita produced a less gastroprotective effect. Furthermore, the isolated fucoidans exhibited a radical scavenging activity.

Conclusion

The comparative study of fucoidans isolated from three species of the genus Cystoseira showed that they have similar chemicals properties and relatives anti-radical, anti-inflammatory and gastroprotective activities which are found to be promising.  相似文献   
82.
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Transvenous (transjugular) liver biopsy consists in taking a liver specimen through a needle introduced into the liver parenchyma from the lumen of a hepatic vein. This procedure was attempted 104 times in 98 patients in whom percutaneous needle liver biopsy was contraindicated because of massive ascites and/or bleeding tendency. A liver specimen was obtained in 100 out of these 104 attempts; the tissue specimens were unfragmented and large enough to allow correct evaluation of liver architecture in 57 biopsies. The procedure was followed by no or only minor complications in all our patients except one who suffered a fatal intraperitoneal hemorrhage in relation to perforation of liver capsule; perforation was due to an excessive front rotation applied to the needle, a maneuver which therefore must be avoided. It is concluded that transvenous liver biopsy is a workable, efficient, and acceptably safe procedure for obtaining liver specimens in patients with massive ascites and/or bleeding tendency.  相似文献   
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In December 2013, during a Zika virus (ZIKV) outbreak in French Polynesia, a patient in Tahiti sought treatment for hematospermia, and ZIKV was isolated from his semen. ZIKV transmission by sexual intercourse has been previously suspected. This observation supports the possibility that ZIKV could be transmitted sexually.Zika virus (ZIKV) is a mosquitoborne arbovirus in the family Flaviviridae, genus Flavivirus. It was first isolated in 1947 from a rhesus monkey in the Zika forest of Uganda (1). Sporadic human cases were reported from the 1960s in Asia and Africa. The first reported large outbreak occurred in 2007 on Yap Island, Federated States of Micronesia (2). The largest known ZIKV outbreak reported started in October 2013 in French Polynesia, South Pacific (3), a territory of France comprising 67 inhabited islands; an estimated 28,000 persons (11% of the population) sought medical care for the illness (4). The most common symptoms of Zika fever are rash, fever, arthralgia, and conjunctivitis. Most of the patients had mild disease, but severe neurologic complications have been described in other patients in French Polynesia (5).  相似文献   
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BackgroundRadial artery access has been shown to reduce mortality and bleeding events, especially in patients with acute coronary syndromes. Despite this, interventional cardiologists experienced in femoral artery access still prefer that route for percutaneous coronary intervention. Little is known regarding the merits of each vascular access in patients stratified by their risk of bleeding.MethodsPatients from the Global Leaders trial were dichotomized into low or high risk of bleeding by the median of the PRECISE-DAPT score. Clinical outcomes were compared at 30 days.ResultsIn the overall population, there were no statistical differences between radial and femoral access in the rate of the primary end point, a composite of all-cause mortality, or new Q-wave myocardial infarction (MI) (hazard ratio [HR] 0.70, 95% confidence interval [CI] 0.42-1.15). Radial access was associated with a significantly lower rate of the secondary safety end point, Bleeding Academic Research Consortium (BARC) 3 or 5 bleeding (HR 0.55, 95% CI 0.36-0.84). Compared by bleeding risk strata, in the high bleeding score population, the primary (HR 0.47, 95% CI 0.26-0.85; P = 0.012; Pinteraction = 0.019) and secondary safety (HR 0.57, 95% CI 0.35-0.95; P = 0.030; Pinteraction = 0.631) end points favoured radial access. In the low bleeding score population, however, the differences in the primary and secondary safety end points between radial and femoral artery access were no longer statistically significant.ConclusionsOur findings suggest that the outcomes of mortality or new Q-wave MI and BARC 3 or 5 bleeding favour radial access in patients with a high, but not those with a low, risk of bleeding. Because this was not a primary analysis, it should be considered hypothesis generating.  相似文献   
88.
Among protease inhibitors, atazanavir has not been associated with urolithiasis in clinical studies. We describe 11 cases of atazanavir-associated urolithiasis in patients with human immunodeficiency virus (HIV) infection. Patients with low water intake, high urinary pH, and a prior history of urinary stones may have a higher risk of atazanavir-associated urine crystallization.  相似文献   
89.
90.
OBJECTIVE: to compare the activities of antioxidative enzymes in erythrocytes between centenarians and a younger group of elderly subjects. DESIGN: cross-sectional study. SETTING: county of Funen, Denmark. SUBJECTS: 41 centenarians aged between 100 and 105 years and 52 community control subjects aged between 60 and 79 years. MEASUREMENTS: enzyme activities of superoxide dismutase (CuZn-SOD), glutathione peroxidase, catalase and glutathione reductase (GR) in erythrocytes. Functional capacity among the centenarians was evaluated by Katz' index of activities of daily living, the Physical Performance Test and Mini-Mental State Examination. RESULTS: the mean CuZn-SOD activity was significantly lower and the mean GR activity was significantly higher in centenarians than in the group of elderly people. The centenarians with the lowest cognitive and physical functional capacity and who did not survive at least 1 year after blood sampling tended to have the lowest CuZn-SOD activities. The range of GR activity was shifted toward higher values in the centenarian group than in the younger group and those centenarians having the best functional capacity tended to have the highest GR activity. CONCLUSIONS: CuZn-SOD activity is decreased in centenarians, probably because of reduced demand for the enzyme at lower metabolic rate and oxygen consumption. Subjects with high GR activity occur more frequently among centenarians than expected, possibly due to their better survival. The role of GR in disease prevention and as a predictor for longevity deserves to be further explored.  相似文献   
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