924 resultados para Equipment Failure Analysis
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Ischemia/reperfusion injury (IRI) is a leading cause of acute renal failure. The definition of the molecular mechanisms involved in renal IRI and counter protection promoted by ischemic pre-conditioning (IPC) or Hemin treatment is an important milestone that needs to be accomplished in this research area. We examined, through an oligonucleotide microarray protocol, the renal differential transcriptome profiles of mice submitted to IRI, IPC and Hemin treatment. After identifying the profiles of differentially expressed genes observed for each comparison, we carried out functional enrichment analysis to reveal transcripts putatively involved in potential relevant biological processes and signaling pathways. The most relevant processes found in these comparisons were stress, apoptosis, cell differentiation, angiogenesis, focal adhesion, ECM-receptor interaction, ion transport, angiogenesis, mitosis and cell cycle, inflammatory response, olfactory transduction and regulation of actin cytoskeleton. In addition, the most important overrepresented pathways were MAPK, ErbB, JAK/STAT, Toll and Nod like receptors, Angiotensin II, Arachidonic acid metabolism, Wnt and coagulation cascade. Also, new insights were gained about the underlying protection mechanisms against renal IRI promoted by IPC and Hemin treatment. Venn diagram analysis allowed us to uncover common and exclusively differentially expressed genes between these two protective maneuvers, underscoring potential common and exclusive biological functions regulated in each case. In summary, IPC exclusively regulated the expression of genes belonging to stress, protein modification and apoptosis, highlighting the role of IPC in controlling exacerbated stress response. Treatment with the Hmox1 inducer Hemin, in turn, exclusively regulated the expression of genes associated with cell differentiation, metabolic pathways, cell cycle, mitosis, development, regulation of actin cytoskeleton and arachidonic acid metabolism, suggesting a pleiotropic effect for Hemin. These findings improve the biological understanding of how the kidney behaves after IRI. They also illustrate some possible underlying molecular mechanisms involved in kidney protection observed with IPC or Hemin treatment maneuvers.
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Complexity in time series is an intriguing feature of living dynamical systems, with potential use for identification of system state. Although various methods have been proposed for measuring physiologic complexity, uncorrelated time series are often assigned high values of complexity, errouneously classifying them as a complex physiological signals. Here, we propose and discuss a method for complex system analysis based on generalized statistical formalism and surrogate time series. Sample entropy (SampEn) was rewritten inspired in Tsallis generalized entropy, as function of q parameter (qSampEn). qSDiff curves were calculated, which consist of differences between original and surrogate series qSampEn. We evaluated qSDiff for 125 real heart rate variability (HRV) dynamics, divided into groups of 70 healthy, 44 congestive heart failure (CHF), and 11 atrial fibrillation (AF) subjects, and for simulated series of stochastic and chaotic process. The evaluations showed that, for nonperiodic signals, qSDiff curves have a maximum point (qSDiff(max)) for q not equal 1. Values of q where the maximum point occurs and where qSDiff is zero were also evaluated. Only qSDiff(max) values were capable of distinguish HRV groups (p-values 5.10 x 10(-3); 1.11 x 10(-7), and 5.50 x 10(-7) for healthy vs. CHF, healthy vs. AF, and CHF vs. AF, respectively), consistently with the concept of physiologic complexity, and suggests a potential use for chaotic system analysis. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4758815]
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Background: A considerable number of metastatic colorectal cancer (mCRC) patients who progress on standard treatment with 5-fluorouracil (5FU), oxaliplatin, irinotecan and monoclonal antibodies, still have adequate performance status and desire further treatment. Mitomycin C (MMC) has been widely used in this context, and despite good tolerability, there are doubts regarding its true benefit. Methods: In order to assess the activity of MMC in the refractory mCRC setting, we retrospectively evaluated 109 heavily pre-treated patients who received MMC as single agent or in combination for mCRC at three different institutions in two countries. Results: Median patient's age was 54 years old, 57% were male and 94% had performance status ECOG 0 or 1. MMC was used in second line in 11%, third line in 38% and fourth line or beyond in 51% of patients. 58% received MMC combinations, mainly with capecitabine. Grade 3 or 4 toxicity was observed in 5% of patients and 6% required dose reductions. Median time to treatment failure (TTF) was 1.7 months with MMC and 3.6 months on the regimen prior to MMC, with a ratio between these TTF below 1 in 82% of patients. Median survival was only 4.5 months (95% confidence interval (CI) of 3.48-5.56). Conclusions: This retrospective data represent the largest reported series of unselected refractory mCRC patients treated with MMC. The median survival of 4.5 months is similar to the survival expected for best supportive care. This lack of activity strongly suggests that MMC should not be routinely used in refractory mCRC. (C) 2012 Elsevier Ltd. All rights reserved.
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Aim: The renin-angiotensin-aldosterone system (RAAS) has dual pathways to angiotensin II production; therefore, multiple blockages may be useful in heart failure. In this study, we evaluated the short-term haemodynamic effects of aliskiren, a direct renin inhibitor, in patients with decompensated severe heart failure who were also taking angiotensin-converting enzyme ( ACE) inhibitors. Materials and methods: A total of 16 patients (14 men, two women, mean age: 60.3 years) were enrolled in the study. The inclusion criteria included hospitalisation due to decompensated heart failure, ACE inhibitor use, and an ejection fraction < 40% (mean: 21.9 +/- 6.7%). The exclusion criteria were: creatinine > 2.0 mg/dl, cardiac pacemaker, serum K+ > 5.5 mEq/l, and systolic blood pressure < 70 mmHg. Patients either received 150 mg/d aliskiren for 7 days (aliskiren group, n = 10) or did not receive aliskiren (control group, n = 6). Primary end points were systemic vascular resistance and cardiac index values. Repeated-measures analysis of variance (ANOVA) was used to assess variables before and after intervention. A two-sided p-value < 0.05 was considered statistically significant. Results: Compared to pre-intervention levels, systemic vascular resistance was reduced by 20.4% in aliskiren patients, but it increased by 2.9% in control patients (p = 0.038). The cardiac index was not significantly increased by 19.0% in aliskiren patients, but decreased by 8.4% in control patients (p = 0.127). No differences in the pulmonary capillary or systolic blood pressure values were observed between the groups. Conclusion: Aliskiren use reduced systemic vascular resistance in patients with decompensated heart failure taking ACE inhibitors.
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Introduction. Patients with terminal heart failure have increased more than the available organs leading to a high mortality rate on the waiting list. Use of Marginal and expanded criteria donors has increased due to the heart shortage. Objective. We analyzed all heart transplantations (HTx) in Sao Paulo state over 8 years for donor profile and recipient risk factors. Method. This multi-institutional review collected HTx data from all institutions in the state of Sao Paulo, Brazil. From 2002 to 2008 (6 years), only 512 (28.8%) of 1777 available heart donors were accepted for transplantation. All medical records were analyzed retrospectively; none of the used donors was excluded, even those considered to be nonstandard. Results. The hospital mortality rate was 27.9% (n = 143) and the average follow-up time was 29.4 +/- 28.4 months. The survival rate was 55.5% (n = 285) at 6 years after HTx. Univariate analysis showed the following factors to impact survival: age (P = .0004), arterial hypertension (P = .4620), norepinephrine (P = .0450), cardiac arrest (P = .8500), diabetes mellitus (P = .5120), infection (P = .1470), CKMB (creatine kinase MB) (P = .8694), creatinine (P = .7225), and Na+ (P = .3273). On multivariate analysis, only age showed significance; logistic regression showed a significant cut-off at 40 years: organs from donors older than 40 years showed a lower late survival rates (P = .0032). Conclusions. Donor age older than 40 years represents an important risk factor for survival after HTx. Neither donor gender nor norepinephrine use negatively affected early survival.
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OBJECTIVES: In this study, we aimed to determine the complications of standard surgical treatments among patients over 75 years in a high-volume urologic center. METHODS: We analyzed 100 consecutive patients older than 75 years who had undergone transurethral prostatic resection of the prostate or open prostatectomy for treatment of benign prostatic hyperplasia from January 2008 to March 2010. We analyzed patient age, prostate volume, prostate-specific antigen level, international prostatic symptom score, quality of life score, urinary retention, co-morbidities, surgical technique and satisfaction with treatment. RESULTS: Median age was 79 years. Forty-eight patients had undergone transurethral prostatic resection of the prostate, and 52 had undergone open prostatectomy. The median International Prostatic Symptom Score was 20, the median prostate volume was 83 g, 51% were using an indwelling bladder catheter, and the median prostate-specific antigen level was 5.0 ng/ml. The most common comorbidities were hypertension, diabetes and coronary disease. After a median follow-up period of 17 months, most patients were satisfied. Complications were present in 20% of cases. The most common urological complication was urethral stenosis, followed by bladder neck sclerosis, urinary fistula, late macroscopic hematuria and persistent urinary incontinence. The most common clinical complication was myocardial infarction, followed by acute renal failure requiring dialysis. Incidental carcinoma of the prostate was present in 6% of cases. One case had urothelial bladder cancer. CONCLUSIONS: Standard surgical treatments for benign prostatic hyperplasia are safe and satisfactory among the elderly. Complications are infrequent, and urethral stenosis is the most common. No clinical variable is associated with the occurrence of complications.
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PURPOSE: To evaluate the effect of inspiratory muscle training (IMT) on cardiac autonomic modulation and on peripheral nerve sympathetic activity in patients with chronic heart failure (CHF). METHODS: Functional capacity, low-frequency (LF) and high-frequency (HF) components of heart rate variability, muscle sympathetic nerve activity inferred by microneurography, and quality of life were determined in 27 patients with CHF who had been sequentially allocated to 1 of 2 groups: (1) control group (with no intervention) and (2) IMT group. Inspiratory muscle training consisted of respiratory exercises, with inspiratory threshold loading of seven 30-minute sessions per week for a period of 12 weeks, with a monthly increase of 30% in maximal inspiratory pressure (PImax) at rest. Multivariate analysis was applied to detect differences between baseline and followup period. RESULTS: Inspiratory muscle training significantly increased PImax (59.2 +/- 4.9 vs 87.5 +/- 6.5 cmH(2)O, P = .001) and peak oxygen uptake (14.4 +/- 0.7 vs 18.9 +/- 0.8 mL.kg(-1).min(-1), P = .002); decreased the peak ventilation (V. E) +/- carbon dioxide production (V-CO2) ratio (35.8 +/- 0.8 vs 32.5 +/- 0.4, P = .001) and the (V) over dotE +/-(V) over dotCO(2) slope (37.3 +/- 1.1 vs 31.3 +/- 1.1, P = .004); increased the HF component (49.3 +/- 4.1 vs 58.4 +/- 4.2 normalized units, P = .004) and decreased the LF component (50.7 +/- 4.1 vs 41.6 +/- 4.2 normalized units, P = .001) of heart rate variability; decreased muscle sympathetic nerve activity (37.1 +/- 3 vs 29.5 +/- 2.3 bursts per minute, P = .001); and improved quality of life. No significant changes were observed in the control group. CONCLUSION: Home-based IMT represents an important strategy to improve cardiac and peripheral autonomic controls, functional capacity, and quality of life in patients with CHF.
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Current methods for quality control of sugar cane are performed in extracted juice using several methodologies, often requiring appreciable time and chemicals (eventually toxic), making the methods not green and expensive. The present study proposes the use of X-ray spectrometry together with chemometric methods as an innovative and alternative technique for determining sugar cane quality parameters, specifically sucrose concentration, POL, and fiber content. Measurements in stem, leaf, and juice were performed, and those applied directly in stem provided the best results. Prediction models for sugar cane stem determinations with a single 60 s irradiation using portable X-ray fluorescence equipment allows estimating the % sucrose, % fiber, and POL simultaneously. Average relative deviations in the prediction step of around 8% are acceptable if considering that field measurements were done. These results may indicate the best period to cut a particular crop as well as for evaluating the quality of sugar cane for the sugar and alcohol industries.
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The objective of this study was to evaluate the push-out bond strength of fiberglass resin reinforced bonded with five ionomer cements. Also, the interface between cement and dentin was inspected by means of SEM. Fifty human canines were chose after rigorous scrutiny process, endodontically treated and divided randomly into five groups (n = 3) according to cement tested: Group I – Ionoseal (VOCO), Group II – Fugi I (GC), Group III – Fugi II Improved (GC), Group IV – Rely X Luting 2 (3M ESPE), Group V – Ketac Cem (3M ESPE). The post-space was prepared to receive a fiberglass post, which was tried before cementation process. No dentin or post surface pretreatment was carried out. After post bonding, all roots were cross-sectioned to acquire 3 thin-slices (1 mm) from three specific regions of tooth (cervical, medium and apical). A Universal test machine was used to carry out the push-out test with cross-head speed set to 0.5mm/mim. All failed specimens were observed under optical microscope to identify the failure mode. Representative specimens from each group was inspected under SEM. The data were analyzed by Kolmogorov-Smirnov and Levene’s tests and by two-way ANOVA, and Tukey’s port hoc test at a significance level of 5%. It was compared the images obtained for determination of types of failures more occurred in different levels. SEM inspection displayed that all cements filled the space between post and dentin, however, some imperfections such bubles and voids were noticed in all groups in some degree of extension. The push-out bond strength showed that cement Ketac Cem presented significant higher results when compared to the Ionoseal (P = 0.02). There were no statistical significant differences among other cements.
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Abstract Introduction Noninvasive ventilation (NIV), as a weaning-facilitating strategy in predominantly chronic obstructive pulmonary disease (COPD) mechanically ventilated patients, is associated with reduced ventilator-associated pneumonia, total duration of mechanical ventilation, length of intensive care unit (ICU) and hospital stay, and mortality. However, this benefit after planned extubation in patients with acute respiratory failure of various etiologies remains to be elucidated. The aim of this study was to determine the efficacy of NIV applied immediately after planned extubation in contrast to oxygen mask (OM) in patients with acute respiratory failure (ARF). Methods A randomized, prospective, controlled, unblinded clinical study in a single center of a 24-bed adult general ICU in a university hospital was carried out in a 12-month period. Included patients met extubation criteria with at least 72 hours of mechanical ventilation due to acute respiratory failure, after following the ICU weaning protocol. Patients were randomized immediately before elective extubation, being randomly allocated to one of the study groups: NIV or OM. We compared both groups regarding gas exchange 15 minutes, 2 hours, and 24 hours after extubation, reintubation rate after 48 hours, duration of mechanical ventilation, ICU length of stay, and hospital mortality. Results Forty patients were randomized to receive NIV (20 patients) or OM (20 patients) after the following extubation criteria were met: pressure support (PSV) of 7 cm H2O, positive end-expiratory pressure (PEEP) of 5 cm H2O, oxygen inspiratory fraction (FiO2) ≤ 40%, arterial oxygen saturation (SaO2) ≥ 90%, and ratio of respiratory rate and tidal volume in liters (f/TV) < 105. Comparing the 20 patients (NIV) with the 18 patients (OM) that finished the study 48 hours after extubation, the rate of reintubation in NIV group was 5% and 39% in OM group (P = 0.016). Relative risk for reintubation was 0.13 (CI = 0.017 to 0.946). Absolute risk reduction for reintubation showed a decrease of 33.9%, and analysis of the number needed to treat was three. No difference was found in the length of ICU stay (P = 0.681). Hospital mortality was zero in NIV group and 22.2% in OM group (P = 0.041). Conclusions In this study population, NIV prevented 48 hours reintubation if applied immediately after elective extubation in patients with more than 3 days of ARF when compared with the OM group. Trial Registration number ISRCTN: 41524441.
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CONTEXT: About 9% of the Brazilian population has gallstones and the incidence increases significantly with aging. The choledocholithiasis is found around 15% of these patients, and a third to half of these cases presented as asymptomatic. Once the lithiasis in the common bile duct is characterized through intraoperative cholangiography, the laparoscopic surgical exploration can be done through the transcystic way or directly through choledochotomy. OBJECTIVE: To evaluate the results and outcomes of the laparoscopic treatment of common bile duct lithiasis. METHODS: Seventy consecutive patients were evaluated. They prospectively underwent the treatment of the lithiasis in the common bile duct and the exploration ways were compared according to the following parameters: criteria on their indication, success in the clearance, surgical complications. It was verified that about ½ of the choledocholithiasis carriers did not show any expression of predictive factors (clinical antecedents of jaundice and/or acute pancreatitis, compatible sonographic data and the pertaining lab tests). The laparoscopic exploration through the transcystic way is favored when there are no criteria for the practice of primary choledochotomy, which are: lithiasis in the proximal bile duct, large (over 8 mm) or numerous calculi (multiple calculosis). RESULTS: The transcystic way was employed in about 50% of the casuistic and the choledochotomy in about 30%. A high success rate (around 80%) was achieved in the clearance of the common bile duct stones through laparoscopic exploration. The transcystic way, performed without fluoroscopy or choledochoscopy, attained a low rate of success (around 45%), being 10% of those by transpapilar pushing of calculi less than 3 mm. The exploration through choledochotomy, either primary or secondary, if the latter was performed after the transcystic route failure, showed high success rate (around 95%). When the indication to choledochotomy was primary, the necessity for choledochoscopy through choledochotomy to help in the removal of the calculi was 55%. However, when choledochotomy was performed secondarily, in situations where the common bile duct diameter was larger than 6 mm, the use of choledochoscopy with the same purpose involved about 20% of the cases. There was no mortality in this series. CONCLUSION: The laparoscopic exploration of the common bile duct was related to a low rate of morbidity. Therefore, the use of laparoscopy for the treatment of the lithiasis in the common bile duct depends on the criteria for the choice of the best access, making it a safe procedure with very good results.
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A method using Liquid Phase Microextraction for simultaneous detection of citalopram (CIT), paroxetine (PAR) and fluoxetine (FLU), using venlafaxine as internal standard, in plasma by high performance liquid chromatography with fluorescence detection was developed. The linearity was evaluated between 5.0 and 500 ng mL-1 (r > 0.99) and the limit of quantification was 2.0, 3.0 and 5.0 ng mL-1 for CIT, PAR and FLU, respectively. Therefore, it can be applied to therapeutic drug monitoring, pharmacokinetics or bioavailability studies and its advantages are that it necessary relatively inexpensive equipment and sample preparation techniques.
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The oregano is a plant, rich in essential oil and very used as spice in the preparation of foods. The objective of this paper was to analyze the viability of irrigation for oregano in Presidente Prudente, São Paulo state, Brazil, including economic risk factors, their effect on irrigation total cost, as well as the different pumping kinds. The Monte Carlo simulation was utilized to study the economic factors: fixed cost, labor, maintenance, pumping and water. The use of irrigation for the oregano in the region of Presidente Prudente is indicated because of its economic feasibility and the reduced risks. The average values of the benefit/cost for all water depths tested were higher than 1, indicating viability. The use of irrigation promoted lower risks compared to the non irrigated crop. The micro irrigation system presented greater sensitivity to changes of prices of the equipment associated to the variation of the useful life of the system. The oregano selling price was the most important factor involved in annual net profit. The water cost was the factor of lesser influence on the total cost. Due to the characteristic of high drip irrigation frequency there was no difference between the tariffs based in use hour of electric energy classified as green and blue, which are characterized by applying different rates on the energy consumption and demand according to the hours of day and times of the year. For the studied region it was recommended drip irrigation water management of oregano with the daily application of 100% of pan evaporation Class A using electric motor with tariffs blue or green.
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The purpose of the present study was to evaluate in vivo the failure rate of metallic brackets bonded with two orthodontic composites. Nineteen patients with ages ranging from 10.5 to 38.7 years needing corrective orthodontic treatment were selected for study. The enamel surfaces from second premolars to second premolars were treated with Transbond Plus-Self Etching Primer (3M Unitek). Next, 380 orthodontic brackets were bonded on maxillary and mandibular teeth, as follows: 190 with Transbond XT composite (3M Unitek) (control) and 190 with Transbond Plus Color Change (3M Unitek) (experimental) in contralateral quadrants. The bonded brackets were light cured for 40 s, and initial alignment archwires were inserted. Bond failure rates were recorded over a six-month period. At the end of the evaluation, six bond failures occurred, three for each composite. Kaplan-Meyer method and log-rank test (Mantel-Cox) was used for statistical analysis, and no statistically significant difference was found between the materials (p=0.999). Both Transbond XT and Transbond Plus Color Change composites had low debonding rates over the study period.
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CONTEXT: Interstitial pregnancy is a rare form of ectopic pregnancy for which the best therapeutic course of action has yet to be determined. Surgical intervention entails a high risk of hemorrhage due to the great vascularization of the cornual region of the uterus. Case descriptions facilitate the analysis of results and aid clinicians in determining the most appropriate course of action in these situations. CASE REPORT: In a patient with an ultrasound diagnosis of interstitial pregnancy, clinical treatment using methotrexate was chosen. However, after one week, there was a marked decline in the serum level of the β subunit of chorionic gonadotropin hormone, although an ultrasound examination revealed embryonic cardiac activity. A second dose of the chemotherapy was administered. Embryonic cardiac activity persisted 48 hours later. Video laparoscopy was performed to achieve right-side cornual resection, which resulted in satisfactory resolution of the case.