849 resultados para High strain rate response


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Retroperitoneal fibrosis (RF) is a rare disease, typically with an insidious clinical course. The peak incidence is seen in patients 40 to 60 years of age and mostly in man. The characteristic finding in this disease is a periaortic fibrous mass that often surrounds the ureters. Although usually regarded as an obstructive uropathy, there has been growing recognition of the condition as a generalized disease. It may have a wide variety of manifestations including mediastinitis, thyroiditis and sclerosing cholangitis. The most common mode of presentation remains abdominal or flank pain with uremia, anemia and a high sedimentation rate. Although ultrasound and renal scintigraphy may contribute to the general evaluation of patients with RF, CT-scanner is the preferred imaging method. The multiplanar imaging capability of magnetic resonance may facilitate assessment of disease extent. The pathogenesis of the disease remains unknown. Steroids and, more recently tamoxifen, appear to be effective in the treatment of the RF. In most instances, RF does not lead to long-term morbidity or affect survival. The three cases of RF reported herein illustrate the varied mode of presentation and the response to the treatment.

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BACKGROUND: Neoadjuvant trials conducted using a double HER2 blockade with lapatinib and trastuzumab, combined with different paclitaxel-containing chemotherapy regimens, have shown high pathological complete response (pCR) rates, but at the cost of important toxicity. We hypothesised that this toxicity might be due to a specific interaction between paclitaxel and lapatinib. This trial assesses the toxicity and activity of the combination of docetaxel with lapatinib and trastuzumab. PATIENTS AND METHODS: Patients with stage IIA to IIIC HER2-positive breast cancer received six cycles of chemotherapy (three cycles of docetaxel followed by three cycles of fluorouracil, epirubicin, cyclophosphamide). They were randomised 1 : 1 : 1 to receive during the first three cycles either lapatinib (1000 mg orally daily), trastuzumab (4 mg/kg loading dose followed by 2 mg/kg weekly), or trastuzumab + lapatinib at the same dose. The primary end point was pCR rate defined as ypT0/is. Secondary end points included safety and toxicity. pCR rate defined as ypT0/is ypN0 was assessed as an exploratory analysis. In June 2012, arm A was closed for futility based on the results from other studies. RESULTS: From October 2010 to January 2013, 128 patients were included in 14 centres. The percentage of the 122 assessable patients with pCR in the breast, and pCR in the breast and nodes, was numerically highest in the lapatinib + trastuzumab group (60% and 56%, respectively), intermediate in the trastuzumab group (52% and 52%), and lowest in the lapatinib group (46% and 36%). Frequency (%) of the most common grade 3-4 toxicities in the lapatinib /trastuzumab/lapatinib + trastuzumab arms were: febrile neutropenia 23/15/10, diarrhoea 9/2/18, infection (other) 9/4/8, and hepatic toxicity 0/2/8. CONCLUSIONS: This study demonstrates a numerically modest pCR rate increase with double anti-HER2 blockade plus chemotherapy, but suggests that the use of docetaxel rather than paclitaxel may not reduce toxicity. CLINICALTRIALSGOV: NCT00450892.

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Background And Objectives: Isolated limb perfusion with TNF-alpha and melphalan (TM-ILP) is a limb salvage therapy for non-resectable soft tissue sarcomas (STS) of the extremities. It is indicated for patients for whom amputation or debilitating surgery is the only alternative. It can be used either as an exclusive therapy (in palliation) or as a neo-adjuvant treatment, followed by marginal resection of tumor remnants with minimal functional impairment. Methods: Between February 1992 and March 2006, 57 TM-ILPs were performed on 51 patients with 88% high grade and 84% advanced stage tumors. Results: Mean follow-up is 38.9 months (4-159, median 22 months). Twenty-one percent patients had significant early complications, with 3 major re-operations, and 23% suffered long-lasting complications. Complete response was observed in 25%, partial response in 42%, stable disease in 14% and progressive disease in 14%. Resection of the tumor remnants was possible in 65%. A complementary treatment was necessary in 31%, mostly radiation therapy. A local recurrence was observed in 35%, after a mean of 20.3 months (2-78), and distant relapse was seen in 45%, after a mean of 13.4 months (5-196). Mean Disease-free survival was 14.9 months, and overall 5-year-survival 43.5%. Amputation rate at 5 years was 24%. Conclusions: TM-ILP is a conservative treatment with a high complications rate, but it can be successful even for the most severe STS of extremities. As a consequence the limb can be spared from amputation or debilitating surgery on the long term in about 75% of patients

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AIM: The aim of this study was to investigate the effect of an acute small ethanol (EtOH) dose (0.5 ml EtOH/kg fat-free mass, combined with carbohydrate) in a drink on endurance performance of trained cyclists. METHODS: Thirteen well-trained male cyclists took part in this study. A 60-min cycling endurance performance test (time trial) was performed in a calorimetric chamber after drinking an EtOH (30 +/- 1.8 ml) or a non-EtOH control (C) drink. RESULTS: Overall, EtOH induced a significant decrease in the average cycling power output (PO) (EtOH: 233 +/- 23 W versus C: 243 +/- 24 W, P < 0.01). The time course of mechanical PO showed an early decrease during the EtOH trial as compared to C (P < 0.01). Due to the lower PO, oxygen consumption, carbon dioxide production and glucose oxidation were significantly lower (P < 0.05) as compared to C. Relative to PO, heart rate response and ratings of perceived exertion (RPE) were increased by EtOH as compared to C (P < 0.05). In contrast, EtOH did not influence gross work efficiency, glycaemia and blood lactate concentration. CONCLUSIONS: These results show that the acute low dose of EtOH decreased endurance performance. An increase of cardio-vascular strain and psychobiological mechanisms may explain this decrease of endurance performance.

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Indoleamine 2,3-dioxygenase 1 (IDO1) is a key regulator of immune responses and therefore an important therapeutic target for the treatment of diseases that involve pathological immune escape, such as cancer. Here, we describe a robust and sensitive high-throughput screen (HTS) for IDO1 inhibitors using the Prestwick Chemical Library of 1200 FDA-approved drugs and the Maybridge HitFinder Collection of 14,000 small molecules. Of the 60 hits selected for follow-up studies, 14 displayed IC50 values below 20 μM under the secondary assay conditions, and 4 showed an activity in cellular tests. In view of the high attrition rate we used both experimental and computational techniques to identify and to characterize compounds inhibiting IDO1 through unspecific inhibition mechanisms such as chemical reactivity, redox cycling, or aggregation. One specific IDO1 inhibitor scaffold, the imidazole antifungal agents, was chosen for rational structure-based lead optimization, which led to more soluble and smaller compounds with micromolar activity.

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PURPOSE: Recurrent head and neck cancer is associated to a poor survival prognosis. A high toxicity rate is demonstrated when surgery and/or radiotherapy and/or chemotherapy are combined. Furthermore, the duration of treatment is often not ethically compatible with the expected survival (median survival<1year). Normal tissues tolerance limits the use of reirradiation and stereotactic body radiotherapy (SBRT) could offer precise irradiation while sparing healthy tissues. After completion of a feasibility study, results of a multicentric study (Lille, Nancy & Nice) using SBRT with cetuximab are reported. The aim of the study was to deliver non toxic short course SBRT (2weeks) in order to get the same local control as the one demonstrated with longer protocols. METHODS AND MATERIALS: Patients with inoperable recurrent, or new primary tumor in a previously irradiated area, were included (WHO<3). Reirradiation (RT) dose was 36Gy in six fractions of 6Gy to the 85% isodose line covering 95% of the PTV with 5 injections of concomitant cetuximab (CT). All patients had previous radiotherapy, 85% had previous surgery and 48% previous chemotherapy. RESULTS: Between 11/2007 and 08/2010, 60 were included (46 men and 14 women), 56 received CT+RT, 3 were not treated and 1 received only CT. Median age was 60 (42-87)) and all 56 patients had squamous carcinoma and received concomitant cetuximab. Mean time between previous radiotherapy and the start of SBRT was 38months. Cutaneous toxicity was observed for 41 patients. There was one toxic death from hemorrhage and denutrition. Median follow-up was 11.4months. At 3months, response rate was 58.4% (95% CI: 43.2-72.4%) and disease control rate was 91.7% (95% CI: 80.0-97.7%). The one-year OS rate was 47.5% (95% CI: 30.8-62.4). CONCLUSION: These results suggest that short SBRT with cetuximab is an effective salvage treatment with good response rate in this poor prognosis population with previously irradiated HNC. Treatment is feasible and, with appropriate care to limiting critical structure, acute toxicities are acceptable. This combination may be the reference treatment is this population.

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The objective of this work was to isolate strains of lactic acid bacteria with probiotic potential from the digestive tract of marine shrimp (Litopenaeus vannamei), and to carry out in vitro selection based on multiple characters. The ideotype (ideal proposed strain) was defined by the highest averages for the traits maximum growth velocity, final count of viable cells, and inhibition halo against nine freshwater and marine pathogens, and by the lowest averages for the traits duplication time and resistance of strains to NaCl (1.5 and 3%), pH (6, 8, and 9), and biliary salts (5%). Mahalanobis distance (D²) was estimated among the evaluated strains, and the best ones were those with the shortest distances to the ideotype. Ten bacterial strains were isolated and biochemically identified as Lactobacillus plantarum (3), L. brevis (3), Weissella confusa (2), Lactococcus lactis (1), and L. delbrueckii (1). Lactobacillus plantarum strains showed a wide spectrum of action and the largest inhibition halos against pathogens, both Gram-positive and negative, high growth rate, and tolerance to all evaluated parameters. In relation to ideotype, L. plantarum showed the lowest Mahalanobis (D²) distance, followed by the strains of W. confusa, L. brevis, L. lactis, and L. delbrueckii. Among the analyzed bacterial strains, those of Lactobacillus plantarum have the greatest potential for use as a probiotic for marine shrimp.

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Abstract:The objective of this work was to evaluate whether a canopy sensor is capable of estimating sugarcane response to N, as well as to propose strategies for handling the data generated by this device during the decision-making process for crop N fertilization. Four N rate-response experiments were carried out, with N rates varying from 0 to 240 kg ha-1. Two evaluations with the canopy sensor were performed when the plants reached average stalk height of 0.3 and 0.5 m. Only two experiments showed stalk yield response to N rates. The canopy sensor was able to identify the crop response to different N rates and the relationship of the nutrient with sugarcane yield. The response index values obtained from the canopy sensor readings were useful in assessing sugarcane response to the applied N rate. Canopy reflectance sensors can help to identify areas responsive to N fertilization and, therefore, improve sugarcane fertilizer management.

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Colorectal cancer (CRC) is the second leading cause of cancer-related death in developed countries. Early detection of CRC leads to decreased CRC mortality. A blood-based CRC screening test is highly desirable due to limited invasiveness and high acceptance rate among patients compared to currently used fecal occult blood testing and colonoscopy. Here we describe the discovery and validation of a 29-gene panel in peripheral blood mononuclear cells (PBMC) for the detection of CRC and adenomatous polyps (AP). Blood samples were prospectively collected from a multicenter, case-control clinical study. First, we profiled 93 samples with 667 candidate and 3 reference genes by high throughput real-time PCR (OpenArray system). After analysis, 160 genes were retained and tested again on 51 additional samples. Low expressed and unstable genes were discarded resulting in a final dataset of 144 samples profiled with 140 genes. To define which genes, alone or in combinations had the highest potential to discriminate AP and/or CRC from controls, data were analyzed by a combination of univariate and multivariate methods. A list of 29 potentially discriminant genes was compiled and evaluated for its predictive accuracy by penalized logistic regression and bootstrap. This method discriminated AP >1cm and CRC from controls with a sensitivity of 59% and 75%, respectively, with 91% specificity. The behavior of the 29-gene panel was validated with a LightCycler 480 real-time PCR platform, commonly adopted by clinical laboratories. In this work we identified a 29-gene panel expressed in PBMC that can be used for developing a novel minimally-invasive test for accurate detection of AP and CRC using a standard real-time PCR platform.

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Aim: Bevacizumab is a monoclonal antibody directed against the vascular endothelial growth factor (VEGF). The previous phase II trial ABIGAIL (Reck, 2010) suggested circulating VEGF as a prognostic, but not predictive, biomarker for patients (pts) with non-small cell lung cancer (NSCLC) treated with bevacizumab. We prospectively measured VEGF in the multicenter phase II trial SAKK19/09 (NCT01116219). Methods: SAKK19/09 enrolled 77 evaluable patients (pts) with previously untreated, advanced nonsquamous NSCLC and EGFR wild type. Pts received 4 cycles of cisplatin 75mg/m2 (or carboplatin AUC5), pemetrexed 500mg/m2 and bevacizumab 7.5mg/kg, followed by maintenance therapy with pemetrexed and bevacizumab until progression by RECIST1.1. Follow-up CT scans were performed every 6 weeks until week 54 and every 12 weeks thereafter. Baseline EDTA blood samples were sent by same-day courier to the central laboratory for centrifugation, aliquoting, and freezing. Upon completion of enrollment, aliquots were thawed, and VEGF quantification was performed centrally using Luminex® Performance Assay Human Base Kit A (R&D Systems, Abingdon, UK). The mean value was used to stratify pts into two groups (low versus high VEGF). Best response rate assessed by RECIST1.1 (CR + PR versus SD + PD). Results: Clinical results of the SAKK19/09 trial were reported previously (Gautschi, 2013). Baseline plasma VEGF was detectable in 71 of 77 (92%) evaluable patients treated with chemotherapy and bevacizumab. The mean value was 74.9 pg/ml, the median 47.5 pg/ml, and the range 3.55 to 310 pg/ml. Using the mean as a predefined cutoff value, 50 patients had low VEGF levels and 21 patients had high VEGF levels. High VEGF was significantly associated with shorter PFS (4.1 vs 8.3 months, HR = 2.56; 95%CI: 1.43- 4.57; p = 0.0015) and OS (8.7 vs 17.5 months, HR = 2.67; 95% CI: 1.37-5.20; p = 0.0041), but not with best response rate ( p = 0.2256). Conclusions: Consistent with the ABIGAIL trial, circulating VEGF was prognostic, but not predictive for response, in the current trial. Further work is ongoing to identify potentially predictive biomarkers for bevacizumab, using comprehensive proteomic analyses. Disclosure: S.I. Rothschild: I received honoraria for the participation in advisory boards from Eli Lilly and Roche and for presentations at scientific symposiums sponsored by Roche; O. Gautschi: Honoraria for advisory boards of Eli Lilly and Roche; R. Cathomas: Advisory board member: Eli Lilly. All other authors have declared no conflicts of interest.

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The effect of the local environment on the energetic strain within small (SiO)N rings (with N=2,3) in silica materials is investigated via periodic model systems employing density functional calculations. Through comparison of the energies of various nonterminated systems containing small rings in strained and relatively unstrained environments, with alpha quartz, we demonstrate how small ring strain is affected by the nature of the embedding environment. We compare our findings with numerous previously reported calculations, often predicting significantly different small-ring strain energies, leading to a critical assessment of methods of calculating accurate localized ring energies. The results have relevance for estimates of the strain-induced response (e.g., chemical, photo, and radio) of small silica rings, and the propensity for them to form in bulk glasses, thin films, and nanoclusters.

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Large scale preparation of hybrid electrical actuators represents an important step for the production of low cost devices. Interfacial polymerization of polypyrrole in the presence of multi-walled carbon nanotubes represents a simple technique in which strong interaction between components is established, providing composite materials with potential applications as actuators due to the synergistic interaction between the individual components, i.e., fast response of carbon nanotubes, high strain of polypyrrole, and diversity in the available geometry of resulting samples.

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The objective of this thesis was to identify the effects of different factors on the tension and tension relaxation of wet paper web after high-speed straining. The study was motivated by the plausible connection between wet web mechanical properties and wet web runnability on paper machines shown by previous studies. The mechanical properties of wet paper were examined using a fast tensile test rig with a strain rate of 1000%/s. Most of the tests were carried out with laboratory handsheets, but samples from a pilot paper machine were also used. The tension relaxation of paper was evaluated as the tension remaining after 0.475 s of relaxation (residual tension). The tensile and relaxation properties of wet webs were found to be strongly dependent on the quality and amount of fines. With low fines content, the tensile strength and residual tension of wet paper was mainly determined by the mechanical interactions between fibres at their contact points. As the fines strengthen the mechanical interaction in the network, the fibre properties also become important. Fibre deformations caused by the mechanical treatment of pulp were shown to reduce the mechanical properties of both dry and wet paper. However, the effect was significantly higher for wet paper. An increase of filler content from 10% to 25% greatly reduced the tensile strength of dry paper, but did not significantly impair wet web tensile strength or residual tension. Increased filler content in wet web was shown to increase the dryness of the wet web after the press section, which partly compensates for the reduction of fibrous material in the web. It is also presumable that fillers increase entanglement friction between fibres, which is beneficial for wet web strength. Different contaminants present in white water during sheet formation resulted in lowered surface tension and increased dryness after wet pressing. The addition of different contaminants reduced the tensile strength of the dry paper. The reduction of dry paper tensile strength could not be explained by the reduced surface tension, but rather on the tendency of different contaminants to interfere with the inter-fibre bonding. Additionally, wet web strength was not affected by the changes in the surface tension of white water or possible changes in the hydrophilicity of fibres caused by the addition of different contaminants. The spraying of different polymers on wet paper before wet pressing had a significant effect on both dry and wet web tensile strength, whereas wet web elastic modulus and residual tension were basically not affected. We suggest that the increase of dry and wet paper strength could be affected by the molecular level interactions between these chemicals and fibres. The most significant increases in dry and wet paper strength were achieved with a dual application of anionic and cationic polymers. Furthermore, selectively adding papermaking chemicals to different fibre fractions (as opposed to adding chemicals to the whole pulp) improved the wet web mechanical properties and the drainage of the pulp suspension.

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Tämän diplomityön tavoitteena oli suunnitella miehistönkuljetusajoneuvon runko. Rungosta suunniteltiin mahdollisimman hyvin energiaa absorboiva. Rakenne toteutettiin kennora-kenteena. Suunnittelussa sovellettiin koneensuunnittelun periaatteiden lisäksi energiaa ab-sorboivien rakenteiden suunnittelun periaatteita. Myös valmistustekniset näkökohdat otet-tiin huomioon. Rakenteessa hyödynnettiin Ruukki Oy:n Ramor 500 suojausterästä sekä OPTIM 500 MC terästä. Lisäksi erilaisten täyteaineiden käyttöä tutkittiin. Suunnittelun työkaluna käytettiin epälineaarista elementtimenetelmää, koska energiaa ab-sorboivien rakenteiden suunnittelussa on otettava huomioon materiaalien epälineaarinen käyttäytyminen. Rakenteen suunnittelu jakaantui viiteen vaiheeseen. Aluksi rakenteeseen kohdistuvat kuormitukset laskettiin elementtimenetelmän avulla. Esisuunnittelussa lasket-tiin plastisuusteorian avulla alustavasti tarvittavat materiaalipaksuudet. Tämän jälkeen ra-kenteen ydingeometria optimoitiin mahdollisimman hyvin energiaa absorboivaksi. Opti-moinnissa hyödynnettiin elementtimenetelmää. Seuraavassa vaiheessa varmistettiin raken-teen globaalit ominaisuudet. Lopuksi rakenteen kestävyyttä tarkasteltiin elementtimene-telmällä. Runko ei mallien mukaan kestänyt siltä vaadittuja kuormitustapauksia. Mallin kaikki ole-tukset pidettiin varmalla puolella. Reunaehdot oletettiin todellisuutta jäykemmiksi. Myös-kään materiaalin venymänopeudesta johtuvaa lujittumista ei otettu huomioon. Koska mii-naräjähdys on monimutkainen tapahtuma, rungon todellinen kestävyys joudutaan ar-viomaan räjähdystesteillä. Elementtimallien perusteella voidaan kuitenkin sanoa, että ener-giaa absorboiva ajoneuvon runko on mahdollista toteuttaa kennorakenteena. Lisäksi voi-daan todeta, että elementtimenetelmää sopii työvälineeksi tämän tyyppisten rakenteiden suunnitteluun.

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This paper describes an electronic transducer for multiphase flow measurement. Its high sensitivity, good signal to noise ratio and accuracy are achieved through an electrical impedance sensor with a special guard technique. The transducer consists of a wide bandwidth and high slew rate differentiator where the lead inductance and stray capacitance effects are compensated. The sensor edge effect is eliminated by using a guard electrode based on the virtual ground potential of the operational amplifier. A theoretical modeling and a calibration method are also presented. The results obtained seem to confirm the validity of the proposed technique.