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21.

Background

Liver stiffness evaluation (LSE) by Fibroscan is now widely used to assess liver fibrosis in chronic hepatitis C. Liver steatosis is a common lesion in chronic hepatitis C as in other chronic liver diseases, but its influence on LSE remains unclear. We aimed to precisely determine the influence of steatosis on LSE by using quantitative and precise morphometric measurements of liver histology.

Methods

650 patients with chronic hepatitis C, liver biopsy, and LSE were included. Liver specimens were evaluated by optical analysis (Metavir F and A, steatosis grading) and by computerized morphometry to determine the area (%, reflecting quantity) and fractal dimension (FD, reflecting architecture) of liver fibrosis and steatosis.

Results

The relationships between LSE and liver histology were better described using morphometry. LSE median was independently linked to fibrosis (area or FD), steatosis (area or FD), activity (serum AST), and IQR/LSE median. Steatosis area ≥4.0 % induced a 50 % increase in LSE result in patients with fibrosis area <9 %. In patients with IQR/LSE median ≤0.30, the rate of F0/1 patients misclassified as F ≥ 2 by Fibroscan was, respectively for steatosis area <4.0 and ≥4.0 %: 12.6 vs 32.4 % (p = 0.003). Steatosis level did not influence LSE median when fibrosis area was ≥9 %, and consequently did not increase the rate of F ≤ 3 patients misclassified as cirrhotic.

Conclusion

A precise evaluation of liver histology by computerized morphometry shows that liver stiffness measured by Fibroscan is linked to liver fibrosis, activity, and also steatosis. High level of steatosis induces misevaluation of liver fibrosis by Fibroscan.  相似文献   
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Individuals with high-level spinal cord injury (SCI) experience low blood pressure (BP) and cognitive impairments. Such dysfunction may be mediated in part by impaired neurovascular coupling (NVC) (i.e., cerebral blood flow responses to neurologic demand). Ten individuals with SCI >T6 spinal segment, and 10 age- and sex-matched controls were assessed for beat-by-beat BP, as well as middle and posterior cerebral artery blood flow velocity (MCAv, PCAv) in response to a NVC test. Tests were repeated in SCI after 10 mg midodrine (alpha1-agonist). Verbal fluency was measured before and after midodrine in SCI, and in the control group as an index of cognitive function. At rest, mean BP was lower in SCI (70±10 versus 92±14 mm Hg; P<0.05); however, PCAv conductance was higher (0.56±0.13 versus 0.39±0.15 cm/second/mm Hg; P<0.05). Controls exhibited a 20% increase in PCAv during cognition; however, the response in SCI was completely absent (P<0.01). When BP was increased with midodrine, NVC was improved 70% in SCI, which was reflected by a 13% improved cognitive function (P<0.05). Improvements in BP were related to improved cognitive function in those with SCI (r2=0.52; P<0.05). Impaired NVC, secondary to low BP, may partially mediate reduced cognitive function in individuals with high-level SCI.  相似文献   
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Hemodynamic instability in amniotic fluid embolism has previously been demonstrated only by right heart catheterization. We present detailed documentation obtained by echocardiography and cardiac catheterization of a 35-year-old woman who developed amniotic fluid embolism and died from severe left ventricular dysfunction and wide QRS complex tachycardia despite intensive medical therapy (inotropes) and mechanical (intraaortic balloon pump) support. © 1996 Wiley-Liss, Inc.  相似文献   
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Parasitology Research - Toxoplasmosis is a zoonosis of worldwide distribution. Currently, two drugs, pyrimethamine and sulfadiazine, are used as a reference in the treatment of toxoplasmosis, but...  相似文献   
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Background and study aimsHelicobacter pylori is the main cause of gastritis, gastroduodenal ulcers and gastric cancer. In the past two decades, the recommended treatment for its eradication as a first-line regimen is the standard triple therapy consisting of a proton pump inhibitor (PPI), amoxicillin and clarithromycin or metronidazole. However, the effectiveness of this traditional regime, which initially was 90%, progressively declined in many parts of the world and is currently 57–73%. The aim of this study was to evaluate whether the eradication rate with triple therapy with levofloxacin is superior as first-line therapy to that with treatment using clarithromycin in the population that attended as outpatients at the Hospital of Lídice.Patients and methodsWe designed a prospective study, with two groups of patients presenting dyspeptic symptoms, from October 2010 to October 2011, who underwent upper gastrointestinal endoscopy and whose biopsies were positive for infection with H. pylori. At the end, 81 patients were included in the order of biopsy result arrival to fill the quota of each group. The first group with 42 patients underwent triple therapy with clarithromycin and the second group with 39 patients underwent therapy with levofloxacin, amoxicillin and a PPI. The patients’ age ranged between 23 and 76 years, the average being 49.5. The predominant sex was female, at 72.84%. Both treatments lasted for 10 days and the patients were clinically re-evaluated 15 days after their conclusion and programmed for a second endoscopy to verify H. pylori eradication.ResultsAmong the 42 patients in the control group, there were 14 eradication failures with 33.33% resistance to clarithromycin. Among the 39 patients in the experimental group, two eradication failures with 5.13% resistance to levofloxacin were observed. The χ2 value was 6.96.ConclusionsTreatment with levofloxacin was more effective than conventional triple therapy. Triple therapy with levofloxacin can be implemented in populations where resistance to clarithromycin has been observed.  相似文献   
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Aims: Our aim was to develop an accurate, non‐invasive, blood‐test‐based method for identifying the main characteristics of liver fibrosis in non‐alcoholic fatty liver disease (NAFLD). Methods: Fibrosis was staged according to NASH‐CRN and Metavir systems in 226 patients with NAFLD. A fully automated algorithm measured the fractal dimension (FD) and the area of fibrosis (AOF). Independent predictors of diagnostic targets were determined using bootstrap methods. Results: (i) Development. Significant fibrosis defined by NASH‐CRN F≥2 was diagnosed by weight, glycaemia, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and prothrombin index [area under the receiver operating characteristic (AUROC)=0.867]; significant fibrosis defined by Metavir F≥2 was diagnosed by weight, age, glycaemia, AST, ALT, ferritin and platelets (FibroMeter AUROC=0.941, P<0.005). AOF was estimated by the combination of hyaluronic acid, glycaemia, AST, ALT, platelets and prothrombin index (aR2=0.530), while FD was estimated by hyaluronic acid, glycaemia, AST/ALT, weight and platelets (aR2=0.529). (ii) Evaluation. Although NASH‐CRN was a better system for fibrosis staging, Metavir staging was a better reference for blood test. Thus, the patient rate with predictive values≥90% by tests was 97.3% with Metavir reference vs. 66.5% with NASH‐CRN reference (P<10?3). FibroMeter showed a significantly higher AUROC than the NAFLD fibrosis score for significant fibrosis, but not for severe fibrosis or cirrhosis, with both staging systems. Relationships between fibrosis lesions were well reflected by blood tests, e.g., the correlation between histological area and FD of fibrosis (rs=0.971, P<10?3) was well reflected by the relationship between respective blood tests (rs=0.852, P<10?3). Conclusions: Different characteristics of fibrosis in NAFLD can be diagnosed and quantified by blood tests with excellent accuracy.  相似文献   
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