998 resultados para rocha de revestimento
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Helminthic diseases have a worldwide distribution. They affect billions of people in endemic areas and can result in serious clinical complications. Some parasites have a human gastrointestinal life cycle with resultant abdominal manifestations. However, the symptoms of helminthic diseases are usually nonspecific. Radiologic imaging, along with the identification of risk factors, may help narrow the differential diagnosis. To avoid diagnostic delays, radiologists should be familiar with the geographic distribution, transmission cycle, and characteristic and atypical manifestations of common helminthic diseases at abdominal imaging with radiography, computed tomography, magnetic resonance imaging, and ultrasonography. Awareness of the clinical, epidemiologic, and pathogenic characteristics of these diseases also may be helpful for narrowing the diagnosis when imaging features are nonspecific. (c) RSNA, 2010 . radiographics.rsna.org
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BACKGROUND: Therapeutic options for patients with advanced hepatocellular carcinoma (HCC) are limited. There is emerging evidence that the growth of cancer cells may be altered by very low levels of electromagnetic fields modulated at specific frequencies. METHODS: A single-group, open-label, phase I/II study was performed to assess the safety and effectiveness of the intrabuccal administration of very low levels of electromagnetic fields amplitude modulated at HCC-specific frequencies in 41 patients with advanced HCC and limited therapeutic options. Three-daily 60-min outpatient treatments were administered until disease progression or death. Imaging studies were performed every 8 weeks. The primary efficacy end point was progression-free survival >= 6 months. Secondary efficacy end points were progression-free survival and overall survival. RESULTS: Treatment was well tolerated and there were no NCI grade 2, 3 or 4 toxicities. In all, 14 patients (34.1%) had stable disease for more than 6 months. Median progression-free survival was 4.4 months (95% CI 2.1-5.3) and median overall survival was 6.7 months (95% CI 3.0-10.2). There were three partial and one near complete responses. CONCLUSION: Treatment with intrabuccally administered amplitude-modulated electromagnetic fields is safe, well tolerated, and shows evidence of antitumour effects in patients with advanced HCC. British Journal of Cancer (2011) 105, 640-648. doi:10.1038/bjc.2011.292 www.bjcancer.com Published online 9 August 2011 (C) 2011 Cancer Research UK
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alpha(5)beta(1) integrin from both wild-type CHO cells (CHO-K1) and deficient in proteoglycan biosynthesis (CHO-745) is post-translationally modified by glycosaminoglycan chains. We demonstrated this using [(35)S]sulfate metabolic labeling of the cells, enzymatic degradation, immunoprecipitation reaction with monoclonal antibody, fluorescence microscopy, and flow cytometry. The alpha(5)beta(1) integrin heterodimer is a hybrid proteoglycan containing both chondroitin and heparan sulfate chains. Xyloside inhibition of sulfate incorporation into alpha(5)beta(1) integrin also supports that integrin is a proteoglycan. Also. cells grown with xyloside adhered on fibronectin with no alteration in alpha(5)beta(1) integrin expression. However, haptotactic motility on fibronectin declined in cells grown with xyloside or chlorate as compared with controls. Thus, alpha(5)beta(1) integrin is a proteoglycan and the glycosaminoglycan chains of the integrin influence cell motility on fibronectin. Similar glycosylation of alpha(5)beta(1) integrin was observed in other normal and malignant cells, suggesting that this modification is conserved and important in the function of this integrin. Therefore, these glycosaminoglycan chains of alpha(5)beta(1) integrin are involved in cellular migration on fibronectin.
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OBJECTIVE. The objective of our study was to describe the T1 and T2 signal intensity characteristics of papillary renal cell carcinoma (RCC) and clear cell RCC with pathologic correlation. MATERIALS AND METHODS. Of 539 RCCs, 49 tumors (21 papillary RCCs and 28 clear cell RCCs) in 45 patients were examined with MRI. Two radiologists retrospectively and independently assessed each tumor`s T1 and T2 signal intensity qualitatively and quantitatively (i.e., the signal intensity [SI] ratio [tumor SI/renal cortex SI]). Of the 49 tumors, 37 (76%) were assessed for pathology features including tumor architecture and the presence of hemosiderin, ferritin, necrosis, and fibrosis. MRI findings and pathology features were correlated. Statistical methods included summary statistics and Wilcoxon`s rank sum test for signal intensity, contingency tables for assessing reader agreement, concordance rate between the two readers with 95% CIs, and Fisher`s exact test for independence, all stratified by RCC type. RESULTS. Papillary RCCs and clear cell RCCs had a similar appearance and signal intensity ratio on T1-weighted images. On T2-weighted images, most papillary RCCs were hypointense (reader 1, 13/21; reader 2, 14/21), with an average mean signal intensity ratio for both readers of 0.67 +/- 0.2, and none was hyperintense, whereas most clear cell RCCs were hyperintense (reader 1, 21/28; reader 2, 17/28), with an average mean signal intensity ratio for both readers of 1.41 +/- 0.4 (p < 0.05). A tumor T2 signal intensity ratio of <= 0.66 had a specificity of 100% and sensitivity of 54% for papillary RCC. Most T2 hypointense tumors exhibited predominant papillary architecture; most T2 hyperintense tumors had a predominant nested architecture (p < 0.05). CONCLUSION. On T2-weighted images, most papillary RCCs are hypointense and clear cell RCCs, hyperintense. The T2 hypointense appearance of papillary RCCs correlated with a predominant papillary architecture at pathology.
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Congenital anomalies of the inferior vena cava (IVC) call represent a difficult for abdominal surgeries, and the radiologist must be aware even of the less common of these anatomical variations. Preaortic iliac venous confluence, also known as marsupial vena cava, is a rare congenital anomaly of the development of the IVC in which the IVC or the left common iliac vein is located anterior to the aortic bifurcation or the right common iliac artery. We report 4 cases of marsupial vena cava detected on multidetector computed tomography examinations in asymptomatic patients and discuss that this congenital anomaly can be recognized more frequently with the use of this new technique based on thinner images.
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Introduction: Xenotransplantation and multivisceral transplantation are advanced therapeutic methods that still require a scientific basis. There are no experimental models of multivisceral transplantation available, particularly not the monitoring by endoscopy. Here, we describe the endoscopic features in a model of multivisceral xenotransplantation. Methods: The distal esophagus, stomach, intestine, colon, liver, pancreas, and the kidneys with a common vascular pedicle were harvested from rabbits and implanted in swine (group I, n = 9) or in rabbits (group II, n = 4). Endoscopy was performed in the stomach, jejunum, and ascending colon at four consecutive time points (immediate after surgery and 10, 90, and 180 min after reperfusion). Lesions were macroscopically graded as mild, moderate, and severe. Biopsies were taken following sacrifice at 180 min after reperfusion. Results: In group I, the stomach, jejunum, and colon manifested a progression of lesions with predominance of mild lesions after 10 min, mild to moderate lesions after 90 min, and moderate to severe lesions after 180 min. In animals from group II, endoscopy showed normal features at all time points after reperfusion. Histopathologic analysis confirmed the diagnosis of hyperacute rejection in group I. Grafts from group II animals presented normal or mild ischemic/reperfusion injury. Conclusion: All animals subjected to multivisceral xenotransplantation showed a progression of endoscopic lesions with time after transplantation, while animals subjected to allotransplantation showed no aberrations in endoscopy. We conclude that endoscopy is a useful tool in the assessment of hyperacute rejection of a xenograft.
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Background and Aim: Although prophylaxis with beta-blockers has been shown to decrease variceal pressure and wall tension in cirrhotic patients, this has not been demonstrated in non-cirrhotic portal hypertension caused by Schistosoma mansoni infection. Methods: Thirteen patients without history of previous gastrointestinal bleeding were included. All of them had high-risk esophageal varices at endoscopy. An endoscopic gauge and a high-frequency endoscopic ultrasonography miniprobe were used to assess transmural variceal pressure and wall tension before and after achieving beta-blockade with propranolol. Results: Baseline variceal pressure decreased from 13.3 +/- 3.5 to 8.2 +/- 2.0 mmHg (P < 0.0001) and wall tension from 500.2 +/- 279.8 to 274.0 +/- 108.3 mg.mm-1. The overall effect of propranolol on decreasing variceal pressure and wall tension expressed in percentage change in relation to baseline values was 35.7 +/- 18.4% and 35.9 +/- 26.7%, respectively (P = 0.9993). Conclusion: Propranolol significantly reduced variceal pressure and wall tension in schistosomiasis.
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The aim of this study was to determine the contribution of preoperative gastric secretory and hormonal response, to the appearance of Barrett`s esophagus in the esophageal stump following subtotal esophagectomy. Thirty-eight end-stage chagasic achalasia patients submitted to esophagectomy and cervical gastric pull-up were followed prospectively for a mean of 13.6 +/- 9.2 years. Gastric acid secretion, pepsinogen, and gastrin were measured preoperatively in 14 patients who have developed Barrett`s esophagus (Group I), and the results were compared to 24 patients who did not develop Barrett`s esophagus (Group II). In the group (I), the mean basal and stimulated preoperative gastric acid secretion was significantly higher than in the group II (basal: 1.52 vs. 1.01, p = 0.04; stimulated: 20.83 vs. 12.60, p = 0.01). Basal and stimulated preoperative pepsinogen were also increased at the Group I compared to Group II (Basal = 139.3 vs. 101.7, p = 0.02; stimulated = 186.0 vs. 156.5, p = 0.07. There was no difference in preoperative gastrin between the two groups. Gastritis was present during endoscopy in 57.1% of the Group I, while it was detected in 16.6% of the Group II, p = 0.014. Barrett`s esophagus in the esophageal stump was associated to high preoperative levels of gastric acid secretion, serum pepsinogen, and also gastritis in the transposed stomach.
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BACKGROUND & AIMS: There is controversy over whether coagulation status predicts bleeding caused by ulceration after esophageal varices band ligation (EVL). METHODS: EVL was performed for primary (n = 45) or secondary (n = 105) prophylaxis in 150 patients with cirrhosis (Child A, n = 74, 49%; Child B, n = 42, 28%; Child C, n = 34, 23%). International normalized ratio (INR) and platelet counts were assessed in all. In 92 patients, levels of factor V, fibrinogen, D-dimer, protein C and protein S, von Willebrand factor, and thromboelastography (TEG) were assessed. Platelet count < 50 x 10(3)/mm(3) and INR > 1.5 were considered high-risk cutoff for bleeding. Conversely, platelet count >= 50 x 10(3)/mm(3) with INR <= 1.5 were safe cutoffs. RESULTS: Overall, 11 patients (7.3%) had post-EVL ulcer bleeding. Bleeding occurred in S patients with Child A/B (4.3%) and 6 patients with Child C (17%) (P = .0174 for Child A/B versus Child C). Eight patients with bleeding were among the 110 below the cutoff for INR and platelet count, whereas only 3 of the patients with bleeding were among the 40 patients with purported high-risk values (P = 1.0). Among the 92 patients with expanded coagulation tests, bleeding occurred in S. There was no difference in any of the coagulation parameters, including overall TEG patterns, between patients who did and did nor bleed. CONCLUSIONS: Post-EVL ulcer bleeding was associated with Child C status but not with conventional or expanded coagulation indices in cirrhotic patients without renal failure or infection undergoing elective EVL. These results call into question the common use of prophylactic procoagulants in the elective setting.
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P>Achalasia surgical treatment alters the esophagogastric junction anatomy (cardiomyotomy plus fundoplication or esophagectomy and gastric pull-up), thus favoring a certain degree of gastroesophageal reflux. Gastric secretory and hormonal functioning is not completely known in chagasic patients. The aim of this study was to evaluate the gastric secretory and hormonal response in patients with end-stage chagasic achalasia compared with normal subjects. Gastric secretion and hormonal response were assessed by estimation of gastric acid secretion (GAS) in basal condition and after pentagastrin stimulation, basal serum gastrin, and serum pepsinogen (SP) in basal condition and after betazole hydrochloride (Histalog (R); Eli Lilly and Company, Indianapolis, IN, USA) stimulation in 27 patients with chagasic achalasia. The results were then compared with those of 24 normal subjects. In the chagasic group, the mean basal and stimulated GAS were significantly lower than in the control group (basal: 1.277 vs. 3.13, P = 0.002; stimulated: 15.9 vs. 35.8, P = 0.0001). Chagasic patients` SG levels showed a significantly higher basal value than the control group (83.3 vs. 36.8, P = 0.0001). There was a significant increase of SP after stimulation compared with the basal levels in both chagasic and control groups. Although the chagasic patients` SP values were higher than the controls, this difference was not statistically significant, either in basal and stimulated conditions (basal: 122.0 vs. 108.9, stimulated 120 min: 177.1 vs. 158.9). In patients with chronic Chagas` disease (ChD), although autonomic denervation does not suppress the strength of the gastric mucosal cells` secretory response to stimulation, it reduces GAS (parietal cell) without, however, affecting SP production (chief cells). On the other hand, the gastrin-producing cells have continuously been stimulated by low GAS.
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Background: Subtotal esophagectomy and gastric pull-up with cervical anastomosis is the main treatment for advanced achalasia. This surgical technique has been associated to esophagitis and also Barrett`s epithelium following esophagectomy. Aim: To analyze late clinical, endoscopic, and pathologic findings in the esophageal stump (ES) mucosa after subtotal esophagectomy in patients treated for advanced chagasic achalasia. Methods: 101 patients submitted to esophagectomy and cervical gastroplasty were followed-up prospectively for a mean of 10.5 +/- 8.8 years. All patients underwent clinical, endoscopic and histopathological evaluation every 2 years. Gastric acid secretion was also assessed. Results: The incidence of esophagitis in the esophageal stump (45.9% at 1 year; 71.9% at 5 years, and 70.0% at 10 years follow-up); gastritis in the transposed stomach (20.4% at 1 year, 31.0% at 5 years, and 40.0% at 10 or more years follow-up), and the occurrence of ectopic columnar metaplasia and Barrett`s Esophagus in the ES (none until 1 year; 10.9% between 1 and 5 years; 29.5% between 5 and 10 years; and 57.5% at 10 or more years follow-up), all rose over time. Gastric acid secretion returns to its preoperative values 4 years postoperatively. Esophageal stump cancer was detected in the setting of chronic esophagitis in five patients: three squamous cell carcinomas and two adenocarcinomas. Conclusion: (1) Esophagitis and Barrett`s esophagus in the esophageal stump rose over time. (2) These mucosal alterations and the development of squamous cell carcinoma and adenocarcinoma are probably due to exposure to duodenogastric reflux, and progressively higher acid output in the transposed stomach.
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Background: Organ shortage impairs the proposition of multivisceral transplantation to treat multiple organ failure. Interspecies (xeno) transplantation is a valid solution for organ shortage; however, suitable models of this advance are lacking. We describe an effective model of multivisceral xenotransplantation to study hyperacute rejection. Methods: Under general anesthesia, we in block recovered the distal esophagus, stomach, small bowel, colon, liver, pancreas, spleen, and kidneys from donors and implanted heterotopically in the lower abdomen of recipients. Animals were divided into four groups: I-canine donor, swine recipient (n = 6); II - swine donor, canine recipient (n = 5); III-canine donor, canine recipient (n = 4); and IV-swine donor, swine recipient (n = 5). Groups I and 11 comprised experimental (xenotransplantation) and III and IV control groups (allotransplantation). During the experiment, we appraised recipient evolution and graft modification by sequential biopsy up to 3 h. At this time, we killed animals for autopsy (experimental end point). Results: We accomplished all experiments successfully. Every grafts attained customary appearance and convenient urine output immediately after unclamp. Around 15 min after reperfusion, xenografts achieved signs of progressive hyperacute rejection and absence of urine output. At the end of experiments we observed moderate to severe hyperacute rejection at small bowel, colon, mesenteric lymph node, liver, spleen, pancreas, and kidney, while stomach and esophagus achieved mild lesions. In contrast, allograft achieved normal or minimum ischemia/reperfusion injury and constant urine output. Conclusion: The present procedure assembles a simple and effective model to study multivisceral xenotransplantation and may ultimately spread researches toward hyperacute rejection.
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Mitochondrial DNA (mtDNA) population data for forensic purposes are still scarce for some populations, which may limit the evaluation of forensic evidence especially when the rarity of a haplotype needs to be determined in a database search. In order to improve the collection of mtDNA lineages from the Iberian and South American subcontinents, we here report the results of a collaborative study involving nine laboratories from the Spanish and Portuguese Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) and EMPOP. The individual laboratories contributed population data that were generated throughout the past 10 years, but in the majority of cases have not been made available to the scientific community. A total of 1019 haplotypes from Iberia (Basque Country, 2 general Spanish populations, 2 North and 1 Central Portugal populations), and Latin America (3 populations from Sao Paulo) were collected, reviewed and harmonized according to defined EMPOP criteria. The majority of data ambiguities that were found during the reviewing process (41 in total) were transcription errors confirming that the documentation process is still the most error-prone stage in reporting mtDNA population data, especially when performed manually. This GHEP-EMPOP collaboration has significantly improved the quality of the individual mtDNA datasets and adds mtDNA population data as valuable resource to the EMPOP database (www.empop.org). (C) 2010 Elsevier Ireland Ltd. All rights reserved.
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One hundred forty-two women with polycystic ovary syndrome (PCOS) with an average body mass index (BMI) of 29.1 kg/m(2) and average age of 25.12 years were studied. By BMI, 30.2% were normal, 38.0% were overweight and 31.6% were obese. Thirty-one eumenorrheic women matched for BMI and age, with no evidence of hyperandrogenism, were recruited as controls. The incidence of dyslipidemia in the PCOS group was twice that of the Control group (76.1% versus 32.25%). The most frequent abnormalities were low high-density lipoprotein cholesterol (HDL-C; 57.6%) and high triglyceride (TG) (28.3%). HDL-C was significantly lower in all subgroups of women with PCOS when compared to the subgroups of normal women. No significant differences were seen in the total cholesterol (p = 0.307), low-density lipoprotein cholesterol (LDL-C; p = 0.283) and TGs (p = 0.113) levels among the subgroups. An independent effect on HDL-C was detected for glucose (p = 0.004) and fasting insulin (p = 0.01); on TG for age (p = 0.003) and homeostatic model assessment insulin resistance (p = 0.03) and on total cholesterol and LDL-C for age (p = 0.02 and p = 0.033, respectively). In conclusion, dyslipidemia is common in women with PCOS, mainly due to low HDL-C levels. BMI has a significant impact on this abnormality.
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Objective: To clarify whether the metabolism of triglyceride-rich lipoproteins and lipid transfer to high-density lipoprotein (HDL) are altered in patients with polycystic ovary syndrome (PCOS). Design: Case control study. Setting: Endocrinology clinics. Patient(s): Eight normal-weight (NW) and 15 obese (013) patients with PCOS were compared with 10 NW and 10 Ob women without PCOS paired for age and body mass index. Intervention(s): Determination of triglyceride-rich lipoprotein metabolism and lipid transfer to HDL. Main Outcome Measure(s): Participants were injected triglyceride-rich emulsions labeled with (14)C-cholesteryl esters and (3)H-triglycerides and the fractional clearance rate (FCR, in min(-1)) of labels was determined. Lipid transfer from artificial nanoemulsions to HDL was performed by incubating radioactively labeled lipid nanoemulsions with plasma during 1 hour, followed by radioactive counting of HDL-containing supernatant after chemical precipitation. Result(s): Lipolysis estimated by triglyceride FCR was equal in PCOS groups (NW = 0.043 +/- 0.032, Ob = 0.033 +/- 0.009) and respective controls (NW = 0.039 +/- 0.015, Ob = 0.044 +/- 0.019). However, the remnant removal as estimated by cholesteryl ester FCR was reduced in both PCOS groups (NW = 0.005 +/- 0.006, Ob = 0.005 +/- 0.005) compared with controls (NW = 0.016 +/- 0.006, Ob = 0.011 +/- 0.072). Lipid transfer rates were not different among groups, but triglyceride transfer rates were positively correlated with homeostasis model assessment estimate of insulin resistance in PCOS. Conclusion(s): PCOS patients showed decreased removal of atherogenic remnants even when fasting glucose was <100 mg/dL. This reinforces the usefulness of the measures taken to prevent cardiovascular events in PCOS patients. (Fertil Steril (R) 2010;93:1948-56. (C)2010 by American Society for Reproductive Medicine.)