905 resultados para CORE NEEDLE BIOPSY
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Presentation at Open Repositories 2014, Helsinki, Finland, June 9-13, 2014
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Incidentally discovered adrenal masses, or adrenal incidentalomas, have become a common clinical problem owing to wide application of radiologic imaging techniques. This definition encompasses a heterogeneous spectrum of pathologic entities, including primary adrenocortical and medullary tumors, benign or malignant lesions, hormonally active or inactive lesions, metastases, and infections. Once an adrenal mass is detected, the clinician needs to address two crucial questions: is the mass malignant, and is it hormonally active? This article provides an overview of the diagnostic clinical approach and management of the adrenal incidentaloma. Mass size is the most reliable variable to distinguish benign and malignant adrenal masses. Adrenalectomy should be recommended for masses greater than 4.0 cm because of the increased risk of malignancy. Adrenal scintigraphy has proved useful in discriminating between benign and malignant lesions. Finally, fine-needle aspiration biopsy is an important tool in the evaluation of oncological patients and it may be useful in establishing the presence of metastatic disease. The majority of adrenal incidentalomas are non-hypersecretory cortical adenomas but an endocrine evaluation can lead to the identification of a significant number of cases with subclinical Cushing's syndrome (5-15%), pheochromocytoma (1.5-13%) and aldosteronoma (0-7%). The first step of hormonal screening should include an overnight low dose dexamethasone suppression test, the measure of urinary catecholamines or metanephrines, serum potassium and, in hypertensive patients, upright plasma aldosterone/plasma renin activity ratio. Dehydroepiandrosterone sulfate measurement may show evidence of adrenal androgen excess.
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The purpose of the present study was to validate the quantitative culture and cellularity of bronchoalveolar lavage (BAL) for the diagnosis of ventilator-associated pneumonia (VAP). A prospective validation test trial was carried out between 1992 and 1997 in a general adult intensive care unit of a teaching hospital. Thirty-seven patients on mechanical ventilation with suspected VAP who died at most three days after a BAL diagnostic procedure were submitted to a postmortem lung biopsy. BAL effluent was submitted to Gram staining, quantitative culture and cellularity count. Postmortem lung tissue quantitative culture and histopathological findings were considered to be the gold standard exams for VAP diagnosis. According to these criteria, 20 patients (54%) were diagnosed as having VAP and 17 (46%) as not having the condition. Quantitative culture of BAL effluent showed 90% sensitivity (18/20), 94.1% specificity (16/17), 94.7% positive predictive value and 88.8% negative predictive value. Fever and leukocytosis were useless for VAP diagnosis. Gram staining of BAL effluent was negative in 94.1% of the patients without VAP (16/17). Regarding the total cellularity of BAL, a cut-off point of 400,000 cells/ml showed a specificity of 94.1% (16/17), and a cut-off point of 50% of BAL neutrophils showed a sensitivity of 90% (19/20). In conclusion, BAL quantitative culture, Gram staining and cellularity might be useful in the diagnostic investigation of VAP.
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The objective of the present study was to determine the efficacy of detection of antigliadin immunoglobulins G and A (IgG and IgA) for the diagnosis of celiac disease in a developing country, since other enteropathies might alter the levels of these antibodies. Three groups were studied: 22 patients with celiac disease (mean age: 30.6 months), 61 patients with other enteropathies (mean age: 43.3 months), and 46 patients without enteropathies (mean age: 96.9 months). Antigliadin IgG and IgA ELISA showed sensitivity of 90.9 and 95.5%, respectively. With the hypothetical values of prevalence ranging from 1:500 to 1:2000 liveborns, the positive predictive value varied from 8.5 to 2.3% for IgG and from 4.8 to 1.1% for IgA. Considering the patients without enteropathies, specificity was 97.8 and 95.7% for IgG and IgA, respectively. In patients with other enteropathies, specificity was 82.0 and 84.1%, respectively. When patients with and without other enteropathies were considered as a whole, specificity was 88.8 and 91.6%, respectively. The specificity of positive IgG or IgA was 93.5% in children without enteropathies and 78.7% in the presence of other enteropathies. The negative predictive value for hypothetical prevalences varying from 1:500 to 1:2000 liveborns was 99.9%. Thus, even in developing countries where the prevalence of non-celiac enteropathies is high, the determination of serum antigliadin antibody levels is a useful screening test prior to the jejunal biopsy in the investigation of intestinal malabsorption.
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Dissolving cellulose is the first main step in preparing novel cellulosicmaterials. Since cellulosic fibres cannot be easily dissolved in water-based solvents, fibres were pretreated with ethanol-acid solution prior to the dissolution. Solubility and changes on the surface of the fibres were studied with microscopy and capillary viscometry. After the treatment, the cellulose fibres were soluble in alkaline urea-water solvent. The nature of this viscous solution was studied rheologically. Cellulose microspheres were prepared by extruding the alkaline cellulose solution through the needle into an acidic medium. By altering the temperature and acidity of the mediumit was possible to adjust the specific surface area and pore sizes of themicrospheres. A typical skin-core structure was found in all samples. Microspheres were oxidised in order to introduce anionic carboxylic acid groups (AGs). Anionic microspheres are more hydrophilic; their water-uptake increased 25 times after oxidation and they could swell almost to their original state (88%) after drying and shrinking. Swelling was studied in simulated physiological environments, corresponding to stomach acid and intestines (pH 1.2-7.4). Oxidised microspheres were used as a drug carriers. They demonstrated a highmass uniformity, which would enable their use for personalised dosing among different patients, including children. The drug was solidified in microspheres in amorphous form. This enhanced solubility and could be used for more challenging drugs with poor solubility. The pores of themicrospheres also remained open after the drug was loaded and they were dried. Regardless of the swelling, the drug was released at a constant rate in all environments.
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Due to various advantages such as flexibility, scalability and updatability, software intensive systems are increasingly embedded in everyday life. The constantly growing number of functions executed by these systems requires a high level of performance from the underlying platform. The main approach to incrementing performance has been the increase of operating frequency of a chip. However, this has led to the problem of power dissipation, which has shifted the focus of research to parallel and distributed computing. Parallel many-core platforms can provide the required level of computational power along with low power consumption. On the one hand, this enables parallel execution of highly intensive applications. With their computational power, these platforms are likely to be used in various application domains: from home use electronics (e.g., video processing) to complex critical control systems. On the other hand, the utilization of the resources has to be efficient in terms of performance and power consumption. However, the high level of on-chip integration results in the increase of the probability of various faults and creation of hotspots leading to thermal problems. Additionally, radiation, which is frequent in space but becomes an issue also at the ground level, can cause transient faults. This can eventually induce a faulty execution of applications. Therefore, it is crucial to develop methods that enable efficient as well as resilient execution of applications. The main objective of the thesis is to propose an approach to design agentbased systems for many-core platforms in a rigorous manner. When designing such a system, we explore and integrate various dynamic reconfiguration mechanisms into agents functionality. The use of these mechanisms enhances resilience of the underlying platform whilst maintaining performance at an acceptable level. The design of the system proceeds according to a formal refinement approach which allows us to ensure correct behaviour of the system with respect to postulated properties. To enable analysis of the proposed system in terms of area overhead as well as performance, we explore an approach, where the developed rigorous models are transformed into a high-level implementation language. Specifically, we investigate methods for deriving fault-free implementations from these models into, e.g., a hardware description language, namely VHDL.
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A 42-year-old male complaining of thoracic spine pain was admitted to the hospital for evaluation. An X-ray and computer tomography of the thoracic spine showed spondylodiscitis of the L3 lumbar and L2-L3 intervertebral disk. The tuberculin skin test (PPD) was strongly positive. A radioscopy-guided fine needle aspirate of the affected area was cultured but did not reveal the cause of the disease. Two biopsy attempts failed to reveal the cause of the disease by culturing or by acid-fast-resistant staining (Ziehl Neelsen) of the specimens. A third biopsy also failed to detect the infectious agent by using microbiological procedures, but revealed the presence of a 245-bp amplicon characteristic of the Mycobacterium tuberculosis complex after PCR of the sample. The result demonstrates the efficacy of PCR for the identification of M. tuberculosis in situations in which conventional diagnosis by culturing techniques or direct microscopy is unable to detect the microorganism. Following this result the patient was treated with the antituberculous cocktail composed by rifampicin, pirazinamide and isoniazid during a six-month period. At the end of the treatment the dorsalgia symptoms had disappeared.
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Sentinel lymph node biopsy (SLNB) is an appropriate method for the evaluation of axillary status in cases of early breast cancer. We report our experience in treating cases evaluated using SLNB. We analyzed a total of 1192 cases assessed by means of SLNB from July 1999 to December 2007. SLNB processing was successfully completed in 1154 cases with the use of blue dye or radiolabeled 99mTc-Dextran-500, or both. Of these 1154 patients, 857 were N0(i-) (no regional lymph node metastasis, negative immunohistochemistry, IHC), 96 were N0(i+) (no regional lymph node metastasis histologically, positive IHC, no IHC cluster greater than 0.2 mm) and 201 were N1mi (greater than 0.2 mm, none greater than 2.0 mm). Most of the tumors (70%) were invasive ductal carcinomas and tumors were staged as T1 in 770 patients (65%). A total of 274 patients underwent SLNB and axillary dissections up to April 2003. The inclusion criteria were tumor size equal to or less than 3 cm in diameter, no clinically palpable axillary lymph nodes, no neoadjuvant therapy. In 19 cases, the SLN could not be identified intraoperatively. A false-negative rate of 11% and a negative predictive value of 88.2% were obtained for the 255 assessable patients. The overall concordance between SLNB and axillary lymph node status was 92%. SLNB sensitivity for nodes was 81% and specificity was 100%. The higher sensitivity, specificity, accuracy, and lower false-negative rates of SLNB suggest that this method may be an appropriate alternative to total axillary dissection in early breast cancer patients.
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Animal models of intervertebral disc degeneration play an important role in clarifying the physiopathological mechanisms and testing novel therapeutic strategies. The objective of the present study is to describe a simple animal model of disc degeneration involving Wistar rats to be used for research studies. Disc degeneration was confirmed and classified by radiography, magnetic resonance and histological evaluation. Adult male Wistar rats were anesthetized and submitted to percutaneous disc puncture with a 20-gauge needle on levels 6-7 and 8-9 of the coccygeal vertebrae. The needle was inserted into the discs guided by fluoroscopy and its tip was positioned crossing the nucleus pulposus up to the contralateral annulus fibrosus, rotated 360° twice, and held for 30 s. To grade the severity of intervertebral disc degeneration, we measured the intervertebral disc height from radiographic images 7 and 30 days after the injury, and the signal intensity T2-weighted magnetic resonance imaging. Histological analysis was performed with hematoxylin-eosin and collagen fiber orientation using picrosirius red staining and polarized light microscopy. Imaging and histological score analyses revealed significant disc degeneration both 7 and 30 days after the lesion, without deaths or systemic complications. Interobserver histological evaluation showed significant agreement. There was a significant positive correlation between histological score and intervertebral disc height 7 and 30 days after the lesion. We conclude that the tail disc puncture method using Wistar rats is a simple, cost-effective and reproducible model for inducing disc degeneration.
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The Banff classification was introduced to achieve uniformity in the assessment of renal allograft biopsies. The primary aim of this study was to evaluate the impact of specimen adequacy on the Banff classification. All renal allograft biopsies obtained between July 2010 and June 2012 for suspicion of acute rejection were included. Pre-biopsy clinical data on suspected diagnosis and time from renal transplantation were provided to a nephropathologist who was blinded to the original pathological report. Second pathological readings were compared with the original to assess agreement stratified by specimen adequacy. Cohen's kappa test and Fisher's exact test were used for statistical analyses. Forty-nine specimens were reviewed. Among these specimens, 81.6% were classified as adequate, 6.12% as minimal, and 12.24% as unsatisfactory. The agreement analysis among the first and second readings revealed a kappa value of 0.97. Full agreement between readings was found in 75% of the adequate specimens, 66.7 and 50% for minimal and unsatisfactory specimens, respectively. There was no agreement between readings in 5% of the adequate specimens and 16.7% of the unsatisfactory specimens. For the entire sample full agreement was found in 71.4%, partial agreement in 20.4% and no agreement in 8.2% of the specimens. Statistical analysis using Fisher's exact test yielded a P value above 0.25 showing that - probably due to small sample size - the results were not statistically significant. Specimen adequacy may be a determinant of a diagnostic agreement in renal allograft specimen assessment. While additional studies including larger case numbers are required to further delineate the impact of specimen adequacy on the reliability of histopathological assessments, specimen quality must be considered during clinical decision making while dealing with biopsy reports based on minimal or unsatisfactory specimens.
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Microparticles obtained by complex coacervation were crosslinked with glutaraldehyde or with transglutaminase and dried using freeze drying or spray drying. Moist samples presented Encapsulation Efficiency (%EE) higher than 96%. The mean diameters ranged from 43.7 ± 3.4 to 96.4 ± 10.3 µm for moist samples, from 38.1 ± 5.36 to 65.2 ± 16.1 µm for dried samples, and from 62.5 ± 7.5 to 106.9 ± 26.1 µm for rehydrated microparticles. The integrity of the particles without crosslinking was maintained when freeze drying was used. After spray drying, only crosslinked samples were able to maintain the wall integrity. Microparticles had a round shape and in the case of dried samples rugged walls apparently without cracks were observed. Core distribution inside the particles was multinuclear and homogeneous and core release was evaluated using anhydrous ethanol. Moist particles crosslinked with glutaraldehyde at the concentration of 1.0 mM.g-1 protein (ptn), were more efficient with respect to the core retention compared to 0.1 mM.g-1 ptn or those crosslinked with transglutaminase (10 U.g-1 ptn). The drying processes had a strong influence on the core release profile reducing the amount released to all dry samples