985 resultados para A even
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Preoperative progressive pneumoperitoneum (PPP) is a safe and effective procedure in the treatment of large incisional hernia (size > 10 cm in width or length) with loss of domain (LIHLD). There is no consensus in the literature on the amount of gas that must be insufflated in a PPP program or even how long it should be maintained. We describe a technique for calculating the hernia sac volume (HSV) and abdominal cavity volume (ACV) based on abdominal computerized tomography (ACT) scanning that eliminates the need for subjective criteria for inclusion in a PPP program and shows the amount of gas that must be insufflated into the abdominal cavity in the PPP program. Our technique is indicated for all patients with large or recurrent incisional hernias evaluated by a senior surgeon with suspected LIHLD. We reviewed our experience from 2001 to 2008 of 23 consecutive hernia surgical procedures of LIHLD undergoing preoperative evaluation with CT scanning and PPP. An ACT was required in all patients with suspected LIHLD in order to determine HSV and ACV. The PPP was performed only if the volume ratio HSV/ACV (VR = HSV/ACV) was a parts per thousand yen25% (VR a parts per thousand yen 25%). We have performed this procedure on 23 patients, with a mean age of 55.6 years (range 31-83). There were 16 women and 7 men with an average age of 55.6 years (range 31-83), and a mean BMI of 38.5 kg/m(2) (range 23-55.2). Almost all patients (21 of 23 patients-91.30%) were overweight; 43.5% (10 patients) were severely obese (obese class III). The mean calculated volumes for ACV and HSV were 9,410 ml (range 6,060-19,230 ml) and 4,500 ml (range 1,850-6,600 ml), respectively. The PPP is performed by permanent catheter placed in a minor surgical procedure. The total amount of CO(2) insufflated ranged from 2,000 to 7,000 ml (mean 4,000 ml). Patients required a mean of 10 PPP sessions (range 4-18) to achieve the desired volume of gas (that is the same volume that was calculated for the hernia sac). Since PPP sessions were performed once a day, 4-18 days were needed for preoperative preparation with PPP. The mean VR was 36% (ranged from 26 to 73%). We conclude that ACT provides objective data for volume calculation of both hernia sac and abdominal cavity and also for estimation of the volume of gas that should be insufflated into the abdominal cavity in PPP.
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Purpose: Hepatectomy remains a complex operation even in experienced hands. The objective of the present study was to describe our experience in liver resections, in the light of liver transplantation, emphasizing the indications for surgery, surgical techniques, complications, and results. Methods: The medical records of 53 children who underwent liver resection for primary or metastatic hepatic tumors were reviewed. Ultrasonography, computed tomographic (CT) scan, and needle biopsy were the initial methods used to diagnose malignant tumors. After neoadjuvant chemotherapy, tumor resectability was evaluated by another CT scan. Surgery was performed by surgeons competent in liver transplantation. As in liver living donor operation, vascular anomalies were investigated. The main arterial anomalies found were the right hepatic artery emerging from the superior mesenteric artery and left hepatic artery from left gastric artery. Hilar structures were dissected very close to liver parenchyma. The hepatic artery and portal vein were dissected and ligated near their entrance to the liver parenchyma to avoid damaging the hilar vessels of the other lobe. During dissection of the suprahepatic veins, the venous infusion was decreased to reduce central venous pressure and potential bleeding from hepatic veins and the vena cava. Results: Fifty-three children with hepatic tumors underwent surgical treatment, 47 patients underwent liver resections, and in 6 cases, liver transplantation was performed because the tumor was considered unresectable. There were 31 cases of hepatoblastoma, with a 9.6% mortality rate. Ten children presented with other malignant tumors-3 undifferentiated sarcomas, 2 hepatocellular carcinomas, 2 fibrolamellar hepatocellular carcinomas, a rhabdomyosarcoma, an immature ovarian teratoma, and a single neuroblastoma. These cases had a 50% mortality rate. Six children had benign tumors-4 mesenchymal hamartoma, 1 focal nodular hyperplasia, and a mucinous cystadenoma. All of these children had a favorable outcome. Hepatic resections included 22 right lobectomies, 9 right trisegmentectomies, 8 left lobectomies, 5 left trisegmentectomies, 2 left segmentectomies, and 1 case of monosegment (segment IV) resection. The overall mortality rate was 14.9%, and all deaths were related to recurrence of malignant disease. The mortality rate of hepatoblastoma patients was less than other malignant tumors (P = .04). Conclusion: The resection of hepatic tumors in children requires expertise in pediatric surgical practice, and many lessons learned from liver transplantation can be applied to hepatectomies. The present series showed no mortality directly related to the surgery and a low complication rate. (C) 2009 Elsevier Inc. All rights reserved.
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Despite modern reanimation surgical techniques, facial paralysis presents with functional and aesthetic deficits. We evaluated facial symmetry after treating with botulinum toxin the healthy side of the face of 25 patients with long-standing facial paralysis who had previously been treated by surgical methods, with 6 months follow-up. Evaluation consisted of a clinical score, the two subscales of the Facial Disability Index, and surface electromyography. The mean botulinum toxin dose was 38 +/- A 5 U (range = 15-69 U). The clinical score showed significant reduction of asymmetry of 48.4% at 1 month and 16.8% after 6 months. The initial result was a consequence of reduced motion on the treated side combined with better motion on the paralyzed side. At 6 months, the treated side returned to basal scores. The residual effect seen in symmetry was due to an increase (18%) of motion in the paralyzed side. There was a significant decrease in the action potential of muscles on the nonparalyzed side 1 month post injection but completely reverted after 6 months. The Physical Function Index increased, but not significantly. The Social/Well-Being Function Index showed a significant increase at 6 months compared to pretreatment. The proposed treatment improved facial symmetry for up to 6 months. Even after the end of the clinical effect of the drug, the paralyzed side`s clinical score was 18% higher than pretreatment, with an increased quality of life.
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An experimental study of the effect of fuel stagnation temperature on mixing in a supersonic hydrogen-air flame is described, The combustor consisted of a constant-area rectangular duct with a centrally located fuel-injection strut that spanned the width. A high-enthalpy stream of air was supplied by a free-piston shock tunnel, and heated hydrogen fuel, supplied by a gun-tunnel, was injected into the freestream as a coflowing planar jet. The freestream total enthalpies were 5.6, 6.5, and 9 MJ/kg, and fuel stagnation temperatures were 300, 450, and 700 K, Raising the fuel stagnation temperature increased the fuel velocity to be near that of the airstream and resulted in a decrease in the mixing rate, Even as the fuel and air velocities became equal, significant mixing still occurred because of a large difference in density, Increasing the freestream enthalpy reduced the difference between the initial air temperature and the adiabatic flame temperature, which in turn reduced the heat addition, and subsequently, the amount of pressure rise in the duct.
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The steady-state resonance fluorescence spectrum of a two-level atom driven by a bichromatic field in a broadband squeezed vacuum is studied. When the carrier frequency of the squeezed vacuum is tuned to the frequency of the central spectral line, anomalous spectral features, such as hole burning and dispersive profiles, can occur at the central line. We show that these features appear for wider, and experimentally more convenient, ranges of the parameters than in the case of monochromatic excitation. ?he absence of a coherent spectral component at the central line makes any experimental attempt to observe these features much easier. We also discuss the general features of the spectrum. When the carrier frequency of the squeezed vacuum is tuned to the first odd or even sidebands, the spectrum is asymmetric and only the sidebands an sensitive to phase. For appropriate choices of the phase the linewidths or only the odd or even sidebands can be reduced. A dressed-stale interpretation is provided.
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A novel flow-tagging technique is presented which was employed to measure gas velocities in the free stream of a shock tube. This method is based on the laser spectroscopic techniques of Laser-Enhanced Ionisation (LEI) and Laser-Induced Fluorescence (LIF). The flow in the shock tube is seeded with small amounts of sodium, and LEI is used to produce a substantial depletion of neutral sodium atom concentration in a well-defined region of the flow, by using two wavelength-resonance excitation and subsequent collisional ionisation. At a specific time delay, single-laser-pulse planar LIF is utilised to produce a two-dimensional (2-D) inverse image of the depleted tagged region downstream of the flow. By measuring the displacement of the tagged region, free stream velocities in a shock tube were determined. Large variations in the concentration of sodium seeded into the flow were observed and even in the presence of these large variations accurate free-stream velocity measurements were obtained. The experimentally determined value for velocity compares very well with the predicted velocity.
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Fructan:fructan fructosyltransferase (FFT) activity was purified about 300-fold from leaves of Lolium rigidura Gaudin by a combination of affinity chromatography, gel filtration, anion exchange and isoelectric focusing. The FFT activity was free of sucrose:sucrose fructosyltransferase and invertase activities. It had an apparent pI of 4.7 as determined by isoelectric focusing, and a molecular mass of about 50000 (gel filtration). The FFT activity utilized the trisaccharides 1-kestose and 6(G)-kestose as sole substrates, but was not able to use 6-kestose as sole substrate. The FFT activity was not saturated when assayed at concentrations of 1-kestose, 6(G)-kestose or (1,1)-kestotetraose of up to 400 mM The rate of reaction of the FFT activity was most rapid when assayed with 1-kestose and was less rapid when assayed with 6(G)-kestose, (1,1)-kestotetraose or (1,1,1)-kestopentaose. The FFT activity when assayed at a relatively high concentration of enzyme activity (approximately equivalent to about half the activity in crude extracts per gram fresh mass) did not synthesize fructan of degree of polymerization > 6, even during extended assays of up to 10 h. When assayed with a combination of 1-kestose and uniformly labelled [C-14]sucrose as substrates, the major reaction was the transfer of a fructosyl residue from 1-kestose to sucrose resulting in the re-synthesis of 1-kestose. Tetrasaccharide and 6(G)-kestose were also synthesized. When assayed with 6(G)-kestose and [C-14]sucrose as substrates, the major reaction of the FFT activity was the synthesis of tetrasaccharide. However, some synthesis of 1-kestose and re-synthesis of 6(G)-kestose also occurred. When 6, kestose was the sole substrate for the FFT activity, synthesis of tetrasaccharide was 2.7 to 3.4-fold slower than when 1-kestose was used as the sole substrate. Owing to differences in the fructan:sucrose fructosyltransferase activity of the FFT with each of the trisaccharides, net synthesis of tetrasaccharide by the FFT was altered significantly in the presence of sucrose. The magnitude of this effect depended on the concentration of the trisaccharides. In the presence of sucrose, 6(G)-kestose could be a substrate of equivalent importance to 1-kestose for synthesis of tetrasaccharide.
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The products formed by a fructan:fructan fructosyltransferase (FFT) activity purified from Lolium rigidum Gaudin were identified after gas chromatography-mass spectrometry of partially methylated alditol acetates, electrospray ionization-mass spectrometry and reversed-phase high-performance liquid chromatography. The FFT activity synthesized oligofructans up to degree of polymerization (DP) 6, but did not synthesize fructans of DP > 6 even when assayed with (1,1,1)-kestopentaose for up to 10 h. The FFT activity when assayed with 1-kestose or 6(G)-kestose synthesized fructan with fructosyl residues almost exclusively linked by beta-2,1-glycosidic linkages. When assayed with 1-kestose, the FFT activity synthesized tetrasaccharides and pentasaccharides with an internal glucosyl residue. The predominant tetrasaccharide was (1&6(G))-kestotetraose and the predominant pentasaccharide was (1&6(G),1)-kestopentaose. By comparison, tetrasaccharides and pentasaccharides extracted from L. rigidum also contained predominantly beta-2,1-glycosidic linked fructans with an internal glucosyl residue. The only exception was that one of the pentasaccharides contained beta-2,1- and beta-2,6-glycosidic linked fructosyl residues. This pentasaccharide was not synthesized by the FFT activity. The role of this FFT activity in formation of oligofructans in L. rigidum is discussed.
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Transport in bidisperse adsorbents is investigated here, while incorporating a two-dimensional model for adsorbate diffusion in the microparticles. The latter treatment permits consideration of the macropore concentration variation around the microparticle surface, and thereby predicts an adsorbate through-flux on the macroscopic coordinate. Such a through-flux has earlier been postulated in the literature, but with unrealistic mechanistic justification. The new model therefore resolves the existing ambiguity in this regard, and covers the entire spectrum of behaviour between microparticle and macropore diffusion control. Computational results show that if the macroscopic adsorbate flux, ignored in the conventional analysis, has a significant contribution to the total flux under macropore control conditions then it is always important even when the microparticle diffusion resistance is not negligible. The effect of various parameters such as relative microparticle size and isotherm heterogeneity on the uptake is also studied and discussed. (C) 1997 Elsevier Science Ltd.
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We analyzed the effect of a 6-week aerobic exercise training program on the in vivo macrophage reverse cholesterol transport (RCT) in human cholesteryl ester transfer protein (CETP) transgenic (CETP-tg) mice. Male CETP-tg mice were randomly assigned to a sedentary group or a carefully supervised exercise training group (treadmill 15 m/min, 30 min sessions, five sessions per week). The levels of plasma lipids were determined by enzymatic methods, and the lipoprotein profile was determined by fast protein liquid chromatography (FPLC). CETP activity was determined by measuring the transfer rate of (14)C-cholesterol from HDL to apo-B containing lipoproteins, using plasma from CETP-tg mice as a source of CETP. The reverse cholesterol transport was determined in vivo by measuring the [(3)H]-cholesterol recovery in plasma and feces (24 and 48 h) and in the liver (48 h) following a peritoneal injection of [(3)H]-cholesterol labeled J774-macrophages into both sedentary and exercise trained mice. The protein levels of liver receptors were determined by immunoblot, and the mRNA levels for liver enzymes were measured using RT-PCR. Exercise training did not significantly affect the levels of plasma lipids or CETP activity. The HDL fraction assessed by FPLC was higher in exercise-trained compared to sedentary mice. In comparison to the sedentary group, a greater recovery of [(3)H]-cholesterol from the injected macrophages was found in the plasma, liver and feces of exercise-trained animals. The latter occurred even with a reduction in the liver CYP7A1 mRNA level in exercised trained animals. Exercise training increased the liver LDL receptor and ABCA-1 protein levels, although the SR-BI protein content was unchanged. The RCT benefit in CETP-tg mice elicited by exercise training helps to elucidate the role of exercise in the prevention of atherosclerosis in humans.
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Background: Progression and long-term renal outcome of lupus nephritis (LN) in male patients is a controversial subject in the literature. The aim of this study was to evaluate the influence of male gender on the renal outcome of LN. Methods: All male (M) LN patients who fulfilled American College of Rheumatology lupus criteria and who were referred for a kidney biopsy from 1999 to 2009 were enrolled in the study. Subjects with end-stage renal disease at baseline, or follow-up time below 6 months, were excluded. Cases were randomly matched to female (F) patients according to the class of LN, baseline estimated glomerular filtration rate (eGFR, Modification of Diet in Renal Disease simplified formula) and follow-up time. Treatment was decided by the clinical staff based on usual literature protocols. The primary endpoint was doubling of serum creatinine and/or end-stage renal disease. The secondary endpoint was defined as a variation of glomerular filtration rate (GFR) per year (Delta GFR/y index), calculated as the difference between final and initial eGFR adjusted by follow-up time for each patient. Results: We included 93 patients (31 M : 62 F). At baseline, M and F patients were not statistically different regarding WHO LN class (II 9.7%, IV 71%, V 19.3%), eGFR (M 62.4 +/- 36.4 ml/min/1.73 m(2) versus F 59.9 +/- 32.7 ml/min/1.73 m(2)), follow-up time (M 44.2 +/- 27.3 months versus F 39.9 +/- 27.9 months), and 24-hour proteinuria (M 5.3 +/- 4.6 g/day versus F 5.2 +/- 3.0 g/day), as well as age, albumin, C3, antinuclear antibody, anti-DNA antibody and haematuria. There was no difference in the primary outcome (M 19% versus F 13%, log-rank p = 0.62). However, male gender was significantly associated with a worse renal function progression, as measured by Delta GFR/y index (beta coefficient for male gender -12.4, 95% confidence interval -22.8 to -2.1, p = 0.02). The multivariate linear regression model showed that male gender remained statistically associated with a worse renal outcome even after adjustment for eGFR, proteinuria, albumin and C3 complement at baseline. Conclusion: In our study, male gender presented a worse evolution of LN (measured by an under GFR recovering) when compared with female patients with similar baseline features and treatment. Factors that influence the progression of LN in men and sex-specific treatment protocols should be further addressed in new studies. Lupus (2011) 20, 561-567.
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Background Brazil has one of the highest stroke mortality rates in the world, these rates are most endemic in the poor. We verified the prevalence of stroke in a deprived neighbourhood in the city of Sao Paulo, Brazil and compared it with other surveys worldwide. Methods A questionnaire with six questions concerning limb and facial weakness, articulation, sensory disturbances, impaired vision, and past diagnosis of stroke was completed door-to-door in a well-defined area of 15 000 people. Questionnaires were considered positive when a participant answered two or more questions about stroke symptoms or the presence of stroke being confirmed by a physician, or at least three questions in the positive, even if not confirmed by a doctor. Results Of the 4496 individuals over 35-years old living in the area, 243 initially screened positive for stroke. The age-adjusted prevalence rate for men was 4 center dot 6% (95% confidence interval 3 center dot 5-5 center dot 7). For women, the prevalence rate was 6 center dot 5% (95% confidence interval 5 center dot 5-7 center dot 5); when considering only one question, the rate was 4 center dot 8% (95% confidence interval 3 center dot 9-5 center dot 7). The most commonly reported symptoms were limb weakness and sensory disturbances. Hypertension and heart disease were the conditions most commonly associated with previous stroke. Conclusion Stroke prevalence rates were higher in this poor neighbourhood compared with other surveys.
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Background: To investigate the association between cardiovascular risk-factor profile and migraine in the elderly, we evaluated a population sample of ageing men and women (65 years or more) living in a low-income area in the city of Sao Paulo, Brazil. Patients and Methods: We investigated migraine status and cardiovascular profile from a baseline of 1450 participants (65-102 years of age) of the Sao Paulo Ageing & Health Study (SPAH), a longitudinal population-based study with low-income elderly in Brazil. The following age and sex-adjusted cardiovascular risk factors were analyzed: blood pressure, pulse pressure, serum total and high-density lipoprotein cholesterol, body mass index, smoking, history of hypertension, diabetes and the 10-year risk of myocardial infarction or coronary heart disease death based on the Framingham Risk Score. Results: The overall prevalence of migraine was 11.4%, and it was 3 times more frequent among women than men (15.3% vs 5.4%; P < 0.0001). Migraineurs were younger than non-migraineurs (mean age 70.6 years vs 72.1 years; P = 0.001, respectively). There was no statistically significant difference regarding the cardiovascular risk-factor profile after adjustment for age and sex among migraineurs and non-migraineurs. Only a decrease in the risk of hypertension among women (OR 0.58; 95% CI 0.38-0.90; P = 0.01) was also observed even after adjustment for age. Conclusions: Overall, we did not find a worse cardiovascular risk profile among elderly migraineurs. An inverse association between hypertension and migraine in women warrants further investigation.
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Background and objectives Fibroblast growth factor 23 (FGF-23) has emerged as a new factor in mineral metabolism in chronic kidney disease (CKD). An important regulator of phosphorus homeostasis, FGF-23 has been shown to independently predict CKD progression in nondiabetic renal disease. We analyzed the relation between FGF-23 and renal outcome in diabetic nephropathy (DN). Design, setting, participants, & measurements DN patients participating in a clinical trial (enalapril+placebo versus enalapril+losartan) had baseline data collected and were followed until June 2009 or until the primary outcome was reached. Four patients were lost to follow-up. The composite primary outcome was defined as death, doubling of serum creatinine, and/or dialysis need. Results At baseline, serum FGF-23 showed a significant association with serum creatinine, intact parathyroid hormone, proteirturia, urinary fractional excretion of phosphate, male sex, and race. Interestingly, FGF-23 was not related to calcium, phosphorus, 25OH-vitamin D, or 24-hour urinary phosphorus. Mean follow-up time was 30.7 +/- 10 months. Cox regression showed that FGF-23 was an independent predictor of the primary outcome, even after adjustment for creatinine clearance and intact parathyroid hormone (10 pg/ml FGF-23 increase = hazard ratio, 1.09; 95% CI, 1.01 to 1.16, P = 0.02). Finally, Kaplan-Meier analysis showed a significantly higher risk of the primary outcome in patients with FGF-23 values of >70 pg/ml. Conclusions FGF-23 is a significant independent predictor of renal outcome in patients with macroalbuminuric DN. Further studies should clarify whether this relation is causal and whether FGF-23 should be a new therapeutic target for CKD prevention. Clin J Am Soc Nephrol 6: 241-247, 2011. doi: 10.2215/CJN.04250510
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The spatial and temporal association of muscle-specific tropomyosin gene expression, and myofibril assembly and degradation during metamorphosis is analyzed in the gastropod mollusc. Haliotis rufescens. Metamorphosis of tile planktonic larva to the benthic juvenile includes rearrangement and atrophy of specific larval muscles, and biogenesis of the new juvenile muscle system. The major muscle of the larva - the larval retractor muscle - reorganizes at metamorphosis, with two suites of cells having different fates. The ventral cells degenerate, while the dorsal cells become part of the developing juvenile mantle musculature. Prior to these changes in myofibrillar structure, tropomyosin mRNA prevalence declines until undetectable in the ventral cells, while increasing markedly in the dorsal cells. In the foot muscle and right shell muscle, tropomyosin mRNA levels remain relatively stable, even trough myofibril content increases. In a population of median mesoderm cells destined to form de novo the major muscle of the juvenile and adult (the columellar muscle), tropomyosin expression is initiated at 45 h after induction of metamorphosis. Myofibrillar filamentous actin is not detected in these cells until about 7 days later. Given that patterns of tropomyosin mRNA accumulation in relation to myofibril assembly and disassembly differ significantly among the four major muscle systems examined, we suggest that different regulatory mechanisms, probably operating at both transcriptional and post-transcriptional levels, control the biogenesis and atrophy of different larval and postlarval muscles at metamorphosis.