21 research outputs found

    Can dynamic imaging, using 18F-FDG PET/CT and CT perfusion differentiate between benign and malignant pulmonary nodules?

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    BACKGROUND: The aim of the study was to derive and compare metabolic parameters relating to benign and malignant pulmonary nodules using dynamic 2-deoxy-2-[fluorine-18]fluoro-D-glucose (18F-FDG) PET/CT, and nodule perfusion parameters derived through perfusion computed tomography (CT). PATIENTS AND METHODS: Twenty patients with 21 pulmonary nodules incidentally detected on CT underwent a dynamic 18F-FDG PET/CT and a perfusion CT. The maximum standardized uptake value (SUVmax) was measured on conventional 18F-FDG PET/CT images. The influx constant (Ki ) was calculated from the dynamic 18F-FDG PET/CT data using Patlak model. Arterial flow (AF) using the maximum slope model and blood volume (BV) using the Patlak plot method for each nodule were calculated from the perfusion CT data. All nodules were characterized as malignant or benign based on histopathology or 2 year follow up CT. All parameters were statistically compared between the two groups using the nonparametric Mann-Whitney test. RESULTS: Twelve malignant and 9 benign lung nodules were analysed (median size 20.1 mm, 9-29 mm) in 21 patients (male/female = 11/9; mean age ± SD: 65.3 ± 7.4; age range: 50-76 years). The average SUVmax values ± SD of the benign and malignant nodules were 2.2 ± 1.7 vs. 7.0 ± 4.5, respectively (p = 0.0148). Average Ki values in benign and malignant nodules were 0.0057 ± 0.0071 and 0.0230 ± 0.0155 min-1, respectively (p = 0.0311). Average BV for the benign and malignant nodules were 11.6857 ± 6.7347 and 28.3400 ± 15.9672 ml/100 ml, respectively (p = 0.0250). Average AF for the benign and malignant nodules were 74.4571 ± 89.0321 and 89.200 ± 49.8883 ml/100g/min, respectively (p = 0.1613). CONCLUSIONS: Dynamic 18F-FDG PET/CT and perfusion CT derived blood volume had similar capability to differentiate benign from malignant lung nodules

    Effects of fluoxetine on functional outcomes after acute stroke (FOCUS): a pragmatic, double-blind, randomised, controlled trial

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    Background Results of small trials indicate that fluoxetine might improve functional outcomes after stroke. The FOCUS trial aimed to provide a precise estimate of these effects. Methods FOCUS was a pragmatic, multicentre, parallel group, double-blind, randomised, placebo-controlled trial done at 103 hospitals in the UK. Patients were eligible if they were aged 18 years or older, had a clinical stroke diagnosis, were enrolled and randomly assigned between 2 days and 15 days after onset, and had focal neurological deficits. Patients were randomly allocated fluoxetine 20 mg or matching placebo orally once daily for 6 months via a web-based system by use of a minimisation algorithm. The primary outcome was functional status, measured with the modified Rankin Scale (mRS), at 6 months. Patients, carers, health-care staff, and the trial team were masked to treatment allocation. Functional status was assessed at 6 months and 12 months after randomisation. Patients were analysed according to their treatment allocation. This trial is registered with the ISRCTN registry, number ISRCTN83290762. Findings Between Sept 10, 2012, and March 31, 2017, 3127 patients were recruited. 1564 patients were allocated fluoxetine and 1563 allocated placebo. mRS data at 6 months were available for 1553 (99·3%) patients in each treatment group. The distribution across mRS categories at 6 months was similar in the fluoxetine and placebo groups (common odds ratio adjusted for minimisation variables 0·951 [95% CI 0·839–1·079]; p=0·439). Patients allocated fluoxetine were less likely than those allocated placebo to develop new depression by 6 months (210 [13·43%] patients vs 269 [17·21%]; difference 3·78% [95% CI 1·26–6·30]; p=0·0033), but they had more bone fractures (45 [2·88%] vs 23 [1·47%]; difference 1·41% [95% CI 0·38–2·43]; p=0·0070). There were no significant differences in any other event at 6 or 12 months. Interpretation Fluoxetine 20 mg given daily for 6 months after acute stroke does not seem to improve functional outcomes. Although the treatment reduced the occurrence of depression, it increased the frequency of bone fractures. These results do not support the routine use of fluoxetine either for the prevention of post-stroke depression or to promote recovery of function. Funding UK Stroke Association and NIHR Health Technology Assessment Programme

    Analysis of forging tool wear with the application of a measuring arm integrated with a laser scanner

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    Praca dotyczy możliwości wykorzystania technik skanowania 3D do kontroli zmian geometrii warstwy wierzchniej narzędzi kuźniczych w oparciu o pomiar zmian geometrycznych odkuwek cyklicznie pobieranych z procesu. Do badań wytypowano proces kucia odkuwki pokrywy stosowanej jako uszczelniacz wału korbowego w samochodach ciężarowych. Szczegółowej analizie poddano zużywanie się narzędzia – wypełniacza, stosowanego w drugiej operacji kucia (w górnym zestawie narzędzi). Badania zostały podzielone na dwa etapy. Pierwszym etapem była analiza zużycia narzędzi na podstawie bezpośredniego skanowania ich powierzchni, a następnie opracowania krzywej zużycia – ubytku materiału w zależności od liczby odkuwek. W drugim etapie przeprowadzono skanowanie wybranej powierzchni cyklicznie pobieranych odkuwek i na tej podstawie dokonywano analizy postępującego przyrostu materiału, co jednocześnie stanowiło ubytek materiału na narzędziach. Następnie wyznaczono charakterystykę zmian geometrii odkuwek i porównano z krzywą zużycia dla narzędzi. Uzyskane analizy wykazały dużą zgodność, co wskazuje na możliwość wykorzystania pośredniej metody skanowania odwrotnego 3D (na podstawie pomiarów powierzchni odkuwek) do analizy zmian geometrii warstwy wierzchniej narzędzi kuźniczych, bez konieczności ich demontażu z agregatu kuźniczego. Zaproponowane przez autorów innowacyjne podejście do oceny aktualnego stanu narzędzia kuźniczego pozwala na podejmowanie decyzji o przedłużeniu bądź skróceniu czasu jego eksploatacji na podstawie rzeczywistego (bieżącego) zużycia, a nie na podstawie sztywno ustalonej trwałości (maksymalnej liczby wykonanych odkuwek). Wykazane w pracy wady i zalety opracowanej metody z wykorzystaniem skanowania 3D pozwalają na wydłużenie czasu eksploatacji oprzyrządowania kuźniczego, a tym samym na wymierne obniżenie kosztów produkcji.The study discusses the possibilities of the application of 3D scanning techniques to control the changes in the geometry of the forging tool surface layer on the basis of a measurement of the geometrical changes of the forgings periodically collected from the process. For the investigations, the process of producing a forging of a lid used as a crankshaft seal in motor trucks was selected. A detailed analysis was performed on the wear of the tool – a filler used in the second forging operation (in the upper tool set). The studies were divided into two stages. The first stage was an analysis of the tools’ wear based on direct scanning of their surface, followed by the elaboration of the wear curve – material loss depending on the number of forgings. The second stage involved scanning of the selected surface of the periodically collected forgings and, based on it, an analysis of the proceeding material growth, which simultaneously constituted a material loss on the tools. Next, the characteristics of the geometry change of the forgings were determined and compared with the wear curve for the tools. The obtained analyses were in a good agreement, which suggests the possibility of using the indirect method of 3D reverse scanning (based on the forging surface measurements) for the analysis of the geometry changes of the forging tool surface layer, without the necessity to disassemble the tools from the forging aggregate. The innovative approach to the assessment of the current state of a forging tool proposed by the authors makes it possible to make decisions about a prolongation or shortening of its operation time based on the actual (pre-sent) wear, rather than on the basis of a predetermined, hardcoded durability (maximal number of produced forgings). The pros and cons of the elaborated method with the use of 3D scanning presented in the paper make it possible to prolong the operation time of forging instrumentation, thus measurably lowering the production costs

    Oxidative stress and airway inflammation in severe exacerbations of COPD

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    Background: A study was undertaken to assess both oxidative stress and inflammation in the lungs of patients with chronic obstructive pulmonary disease (COPD) during severe and very severe exacerbations compared with those with stable COPD, healthy smokers, and non-smokers. Two sites within the lungs were compared: the large airways (in sputum) and the peripheral airways (by bronchoalveolar lavage (BAL)). Methods: BAL fluid cell numbers and levels of tumour necrosis factor (TNFα) and interleukin (IL)-8 were measured as markers of airway inflammation and glutathione (GSH) levels as a marker of antioxidant status. Nuclear translocation of the pro-inflammatory transcription factors nuclear factor-κB (NF-κB) and activator protein 1 (AP-1) were also measured by electromobility shift assay in BAL fluid leucocytes and lung biopsy samples. Results: Influx of inflammatory cells into the peripheral airways during exacerbations of COPD was confirmed. Increased IL-8 levels were detected in BAL fluid from patients with stable COPD compared with non-smokers and healthy smokers, with no further increase during exacerbations. In contrast, IL-8 levels in the large airways increased during exacerbations. GSH levels were increased in the BAL fluid of smokers (444%) and patients with stable COPD (235%) compared with non-smokers and were reduced during exacerbations (severe 89.2%; very severe 52.3% compared with stable COPD). NF-κB DNA binding in BAL leucocytes was decreased in healthy smokers compared with non-smokers (41.3%, n = 9, p<0.001) but did not differ in COPD patients, whereas AP-1 DNA binding was significantly decreased during exacerbations of COPD. Conclusion: There is evidence of increased oxidative stress in the airways of patients with COPD that is increased further in severe and very severe exacerbations of the disease. This is associated with increased neutrophil influx and IL-8 levels during exacerbations

    Analysis of the Forming Process of Energy-Absorbing Elements made from 7000 Series High-Strength Aluminum Alloy

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    The paper covers the research on the process of solutionizing of 7075 aluminum alloy in cold tools during the stamping of a high-strength structural element (B-pillar’s base). For technological reasons, in order to obtain high strength parameters of the 7075 alloy, it is necessary to carry out a solutionization process, which allows to obtain dispersion strengthening during ageing process. Properly performed heat treatment of the alloy increases the strength of the material to approx. 600 MPa. The combination of the process of solutionization with simultaneous shaping is aimed at improving and simplifying technological operations of aluminum alloy stamping, shortening the duration of the manufacturing process and reducing production costs. The manufactured lower part of the B-pillar will be used for the verification of the validity of the developed method. During the experiment, a series of stamping tests were carried out, in which the lubricants, pressure and position of the upper and lower blankholders were the variables. The obtained results allow to estimate the influence of the cooling conditions on the strength of the drawpieces obtained after the process of artificial ageing. In order to verify and analyse the results more quickly, a numerical simulation was carried out

    Helicobacter pylori infection in North-East Poland between 1996 and 2011 on the base of histological examination

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    Purpose: The aim of the study was to conduct a 15- year (1996-2011) observations on the frequency of Helicobacter pylori stomach infection in patients having performed gastroscopy in the Endoscopy Unit District Hospital of Białystok, Poland Materials and methods: Out of the 27421 patients who underwent a gastroscopy in 1996-1997, 2000- 2001, 2005-2006, and 2010-2011 years were selected 4216 subjects who had performed histological examination of gastric mucosal specimens for H. pylori infection. The mucosal specimens after placed in buffered formalin, were subjected to standard histological procedure, and stained with hematoxylineosin and Giemsa. Results: Stomach infection with H. pylori was 73.36% (1996-1997), 48.60% (2000-2001), 33.61% (2005-2006) and 32.30% (2010-2011); only between the last two 2-year intervals the difference was not significant. Conclusions: The results of current study indicate on steadily declining stomach infection with H. pylori. Keywords: Helicobacter pylori, histology, gastric mucos

    Buparlisib with thoracic radiotherapy and its effect on tumour hypoxia: A phase I study in patients with advanced non-small cell lung carcinoma

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    Background Pre-clinically, phosphoinositide 3-kinase (PI3K) inhibition radiosensitises tumours by increasing intrinsic radiosensitivity and by reducing tumour hypoxia. We assessed whether buparlisib, a class 1 PI3K inhibitor, can be safely combined with radiotherapy in patients with non-small cell lung carcinoma (NSCLC) and investigated its effect on tumour hypoxia. Methods This was a 3 + 3 dose escalation and dose expansion phase I trial in patients with advanced NSCLC. Buparlisib dose levels were 50 mg, 80 mg and 100 mg once daily orally for 2 weeks, with palliative thoracic radiotherapy (20 Gy in 5 fractions) delivered during week 2. Tumour hypoxic volume (HV) was measured using 18F-fluoromisonidazole positron-emission tomography–computed tomography at baseline and following 1 week of buparlisib. Results Twenty-one patients were recruited with 9 patients evaluable for maximum tolerated dose (MTD) analysis. No dose-limiting toxicity was reported; therefore, 100 mg was declared the MTD, and 10 patients received this dose in the expansion phase. Ninety-four percent of treatment-related adverse events were ≤grade 2 with fatigue (67%), nausea (24%) and decreased appetite (19%) most common per patient. One serious adverse event (grade 3 hypoalbuminaemia) was possibly related to buparlisib. No unexpected radiotherapy toxicity was reported. Ten (67%) of 15 patients evaluable for imaging analysis were responders with 20% median reduction in HV at the MTD. Conclusion This is the first clinical trial to combine a PI3K inhibitor with radiotherapy in NSCLC and investigate the effects of PI3K inhibition on tumour hypoxia. This combination was well tolerated and PI3K inhibition reduced hypoxia, warranting investigation into whether this novel class of radiosensitisers can improve radiotherapy outcomes
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