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Παρασκευή 25 Αυγούστου 2017
Scholar : Aphasiology, Volume 31, Issue 10, October 2017 is now available online on Taylor & Francis Online
Effects of different fertilizers on growth and nutrient uptake of Lolium multiflorum grown in Cd-contaminated soils
Abstract
This study aimed to explore the effects of different fertilizers and their combinations on growth and nutrient and Cd uptake of Lolium multiflorum. Compared with control treatment, chemical fertilizer, organic manure, and their conjunctions with biofertilizer increased shoot biomass. Biofertilizers were found to cause significant reductions in shoot biomass of plants grown in organic manure-treated and control soil. Decreased soil-available N and P and shoot N and K concentrations in biofertilizer amendment treatments indicated that plant growth and nutrient absorption might be negatively affected under nutrient deficiency conditions. Elevated shoot biomasses contributed to the highest shoot Cd contents in chemical fertilizer and chemical fertilizer + biofertilizer treatments among all treatments. But the maximum translocation efficiency occurred in biofertilizer + chemical fertilizer + organic manure treatment, followed by organic manure and chemical fertilizer + organic manure treatments. Based on the results, we can conclude that the application of only the biofertilizer Bacillus subtilis should be avoided in nutrient-limited soils. Chemical fertilizer application could benefit the amount of Cd in shoots, and organic manure application and its combinations could result in the higher translocation efficiency.
http://ift.tt/2walBeX
Goal Impact Influences The Evaluative Component of Performance Monitoring: Evidence From ERPs
Source:Biological Psychology
Author(s): Mario Carlo Severo, Wioleta Walentowska, Agnes Moors, Gilles Pourtois
Successful performance monitoring (PM) requires continuous assessment of context and action outcomes. Electrophysiological studies have reliably identified event-related potential (ERP) markers for evaluative feedback processing during PM: the Feedback-Related Negativity (FRN) and P3 components. The functional significance of FRN remains debated in the literature, with recent research suggesting that feedback's goal relevance can account for FRN (amplitude) modulation, apart from its valence or expectedness alone. Extending this account, the present study assessed whether graded differentiations in feedback's relevance or importance to one's goal (referred to as goal impact) would influence PM at the FRN (and P3) level. To this end, we ran a within-subject crossover design experiment in which 40 participants completed two standard cognitive control tasks (Go/No Go and Simon), while 64-channel electroencephalography was recorded. Critically, both tasks entailed similar reward processing but systematically varied in goal impact assignment (high vs. low), manipulated through their supposed diagnosticity for daily life functioning and activation of social comparison. ERP results showed that goal impact reliably modulated FRN in a general manner. Irrespective of feedback valence, it was overall less negative in the high compared to the low impact condition, suggesting a general decrease in feedback monitoring in the former compared to the latter condition. These findings lend support to the idea that PM is best conceived operating not solely based on motor cues, but is shaped by motivational demands.
http://ift.tt/2xi7GUf
Scholar : These new articles for Classroom Discourse are available online
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Relation between thoracic aortic inflammation and features of plaque vulnerability in the coronary tree in patients with non-ST-segment elevation acute coronary syndrome undergoing percutaneous coronary intervention. An FDG-positron emission tomography and optical coherence tomography study
Abstract
Purpose
To evaluate the relationship between aortic inflammation as assessed by 18F–fluorodeoxyglucose-positron emission tomography (18F–FDG-PET) and features of plaque vulnerability as assessed by frequency domain-optical coherence tomography (FD-OCT).
Methods
We enrolled 30 consecutive non-ST-segment elevation acute coronary syndrome patients undergoing percutaneous coronary intervention. All patients underwent three-vessel OCT before intervention and 18F–FDG-PET before discharge. Univariable and C-reactive protein (CRP)-adjusted linear regression analyses were performed between features of vulnerability [namely:lipid-rich plaques with and without macrophages and thin cap fibroatheromas (TCFA)] and 18F–FDG uptake in both ascending (AA) and descending aorta (DA) [measured either as averaged mean and maximum target-to-blood ratio (TBR) or as active slices (TBRmax ≥ 1.6)].
Results
Mean age was 62 years, and 26 patients were male. On univariable linear regression analysis TBRmean and TBRmax in DA was associated with the number of lipid-rich plaques (β = 4.22; 95%CI 0.05–8.39; p = 0.047 and β = 3.72; 95%CI 1.14–6.30; p = 0.006, respectively). TBRmax in DA was also associated with the number of lipid-rich plaques containing macrophages (β = 2.40; 95%CI 0.07–4.72; p = 0.044). A significant CRP adjusted linear association between the TBRmax in DA and the number of lipid-rich plaques was observed (CRP-adjusted β = 3.58; 95%CI -0.91-6.25; p = 0.01). TBRmax in DA showed a trend towards significant CRP-adjusted association with number of lipid-rich plaques with macrophages (CRP-adjusted β = 2.30; 95%CI -0.11-4.71; p = 0.06). We also observed a CRP-adjusted (β = 2.34; 95%CI 0.22–4.47; p = 0.031) linear association between the number of active slices in DA and the number of lipid-rich plaques. No relation was found between FDG uptake in the aorta and the number of TCFAs.
Conclusions
In patients with first NSTEACS, 18F–FDG uptake in DA is correlated with the number of OCT detected lipid-rich plaques with or without macrophages. This association may be independent from CRP values.
http://ift.tt/2wtAoUr
Influence of body mass index and type of low-level exercise on the side effect profile of regadenoson
Abstract
Purpose
Regadenoson, an A2A adenosine receptor pharmacologic stress agent for radionuclide myocardial perfusion imaging (MPI), is administered as a single, fixed dose. We studied the side effect profile of regadenoson combined with two types of low-level exercise, according to body mass index (BMI).
Methods
Three hundred and fifty-six patients (46.1% men, mean age 67.7±10.7 years, range 31–90 years) underwent regadenoson stress testing combined with low-level exercise. Subjects were classified according to BMI as normal, overweight, or obese, and the type of low-level exercise performed as walking on the treadmill (TE group, n=190) or forcefully swinging legs while sitting (SS group, n=166). Patients' demographics, medical history, clinical symptoms during stress, changes in ECG, oxygen saturation (SatO2), systolic blood pressure (SBP), and heart rate (HR) were evaluated.
Results
Groups were comparable (p=ns) with regard to cardiovascular risks factors. The incidence of side effects was similar across BMI (p=ns), although the TE patients showed improved profiles over those with SS exercise, with a significantly lower incidence of flushing, dizziness and nausea/gastrointestinal discomfort (12.9% vs. 28.4%; 19.9% vs. 33.4%; 11.4% vs. 19.2%, respectively; all p<0.05).
Regarding the hemodynamic response, we did not observe significant changes in SBP and HR after regadenoson administration across BMI categories. Comparing the TE and SS groups, no significant changes were observed in SBP, but there was a higher increase in HR in the TE group (p<0.05).
Conclusions
Regadenoson in combination with low-level exercise is safe and well tolerated over a wide range of BMI, with TE exercise showing a better side effect profile than SS.
http://ift.tt/2w9UyA9
The accuracy of 68 Ga-PSMA PET/CT in primary lymph node staging in high-risk prostate cancer
Abstract
Purpose
To assess the diagnostic accuracy of 68Ga-PSMA PET in predicting lymph node (LN) metastases in primary N staging in high-risk and very high-risk nonmetastatic prostate cancer in comparison with morphological imaging.
Methods
This was a multicentre trial of the Society of Urologic Oncology in Turkey in conjunction with the Nuclear Medicine Department of Cerrahpasa School of Medicine, Istanbul University. Patients were accrued from eight centres. Patients with high-risk and very high-risk disease scheduled to undergo surgical treatment with extended LN dissection between July 2014 and October 2015 were included. Either MRI or CT was used for morphological imaging. PSMA PET/CT was performed and evaluated at a single centre. Sensitivity, specificity and accuracy were calculated for the detection of lymphatic metastases by PSMA PET/CT and morphological imaging. Kappa values were calculated to evaluate the correlation between the numbers of LN metastases detected by PSMA PET/CT and by histopathology.
Results
Data on 51 eligible patients are presented. The sensitivity, specificity and accuracy of PSMA PET in detecting LN metastases in the primary setting were 53%, 86% and 76%, and increased to 67%, 88% and 81% in the subgroup with of patients with ≥15 LN removed. Kappa values for the correlation between imaging and pathology were 0.41 for PSMA PET and 0.18 for morphological imaging.
Conclusions
PSMA PET/CT is superior to morphological imaging for the detection of metastatic LNs in patients with primary prostate cancer. Surgical dissection remains the gold standard for precise lymphatic staging.
http://ift.tt/2iwe8DG
Prognostic importance of lymph node-to-primary tumor standardized uptake value ratio in invasive squamous cell carcinoma of uterine cervix
Abstract
Purpose
Using integrated PET/CT, we evaluated the prognostic value of [18F]FDG uptake ratio between pelvic lymph node (LN) and primary tumor in invasive squamous cell carcinoma (SCCA) of the uterine cervix.
Methods
We retrospectively reviewed patients with International Federation of Gynecology and Obstetrics (FIGO) stages IB to IIA cervical SCCA who underwent preoperative [18F]FDG PET/CT scans. PET/CT parameters such as maximum standardized uptake value (SUV) of the primary cervical cancer (SUVcervix) and LN (SUVLN), and the LN-to-cervical cancer SUV ratio (SUVLN/SUVcervix) were assessed. Prognostic values of PET/CT-derived metabolic and volumetric variables and clinicopathology parameters were analyzed to predict progression-free survival (PFS) in regression analyses.
Results
Clinical data, treatment modalities, and results were reviewed for 103 eligible patients. Median post-surgical follow-up was 29 months (range, 6–89), and 19 (18.5%) patients experienced recurrence. Multivariate logistic regression analysis showed that SUVLN / SUVcervix > 0.1747(P = 0.048) was the independent risk factor of recurrence. Patient group categorized by SUVLN/SUVcervix showed significant difference in PFS (log-rank test, P < 0.001).
Conclusions
Preoperative SUVLN/SUVcervix measured by [18F]FDG PET/CT was significantly associated with recurrence, and has an incremental prognostic value for PFS in patients with cervical SCCA.
http://ift.tt/2ga6duQ
Metabolic volume performs better than SUVmax in the detection of left ventricular assist device driveline infection
Abstract
Purpose
A continuous-flow left ventricular assist device (LVAD) is a new and highly promising therapy in supporting end-stage heart failure patients, either bridging them to heart transplantation or as a destination therapy. Infection is one of the major complications associated with LVAD implants. 18F–FDG PET/CT has already been shown to be useful in the detection of LVAD infection. The goal of this study was to compare the diagnostic accuracy of different PET analysis techniques (visual grading versus SUVmax and metabolic volume).
Methods
We retrospectively analyzed 48 patients with implanted LVAD who underwent an 18F–FDG PET/CT that were either suspected to have a driveline or device infection or inflammation of unknown origin. PET/CT was analyzed qualitatively (visual grading) and quantitatively (SUVmax and metabolic volume) and matched to the final clinical diagnosis concerning driveline infection. The final diagnosis (standard of reference) was made at the end of clinically recorded follow-up or transplantation and included microbiological cultures of the driveline exit site and/or surgical samples, and clinical signs of infection despite negative cultures as well as recurrence of symptoms.
Results
Sensitivity, specificity, positive and negative predictive value were 87.5%, 79%, 81% and 86% for visual score, 87.5%, 87.5%, 87.5% and 87.5% for SUVmax and 96%, 87.5%, 88.5%, 95.5% for metabolic volume, respectively. ROC analysis revealed an AUC of .929 for SUVmax and .969 for metabolic volume. Both SUVmax and metabolic volume had a high detection rate of patients with driveline infection (21/24 = 91.5% true positive vs. 23/26 = 88.5% true positive, respectively). However, metabolic volume detected more patients without any infection correctly (1/22 = 4.5% false negative vs. 3/24 = 12.5% false negative).
Conclusions
18F–FDG PET/CT is a valuable tool for the diagnosis of LVAD driveline infection with high diagnostic accuracy. Particularly the use of the metabolic volume yields very high accuracy and performs slightly better than SUVmax.
http://ift.tt/2warV6e
Prediction of breast cancer recurrence using lymph node metabolic and volumetric parameters from 18 F-FDG PET/CT in operable triple-negative breast cancer
Abstract
Purpose
Triple-negative breast cancer has a poor prognosis. We evaluated several metabolic and volumetric parameters from preoperative 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) in the prognosis of triple-negative breast cancer and compared them with current clinicopathologic parameters.
Methods
A total of 228 patients with triple-negative breast cancer (mean age 47.0 ± 10.8 years, all women) who had undergone preoperative PET/CT were included. The PET/CT metabolic parameters evaluated included maximum, peak, and mean standardized uptake values (SUVmax, SUVpeak, and SUVmean, respectively). The volumetric parameters evaluated included metabolic tumor volume (MTV) and total lesion glycolysis (TLG). Metabolic and volumetric parameters were evaluated separately for tumor (T) and lymph nodes (N). The prognostic value of these parameters was compared with that of clinicopathologic parameters.
Results
All lymph node metabolic and volumetric parameters showed significant differences between patients with and without recurrence. However, tumor metabolic and volumetric parameters showed no significant differences. In a univariate survival analysis, all lymph node metabolic and volumetric parameters (SUVmax-N, SUVpeak-N, SUVmean-N, MTV-N, and TLG-N; all P < 0.001), T stage (P = 0.010), N stage (P < 0.001), and TNM stage (P < 0.001) were significant parameters. In a multivariate survival analysis, SUVmax-N (P = 0.005), MTV (P = 0.008), and TLG (P = 0.006) with TNM stage (all P < 0.001) were significant parameters.
Conclusions
Lymph node metabolic and volumetric parameters were significant predictors of recurrence in patients with triple-negative breast cancer after surgery. Lymph node metabolic and volumetric parameters were useful parameters for evaluating prognosis in patients with triple-negative breast cancer by 18F-FDG PET/CT, rather than tumor parameters.
http://ift.tt/2gaIA5I
Highlights of articles published in annals of nuclear medicine 2016
Abstract
This article is the first installment of highlights of selected articles published during 2016 in the Annals of Nuclear Medicine, an official peer-reviewed journal of the Japanese Society of Nuclear Medicine. A companion article highlighting selected articles published during 2016 in the European Journal of Nuclear Medicine and Molecular Imaging, which is the official peer-reviewed journal of the European Association of Nuclear Medicine, will also appear in the Annals Nuclear Medicine. This new initiative by the respective journals will continue as an annual endeavor and is anticipated to not only enhance the scientific collaboration between Europe and Japan but also facilitate global partnership in the field of nuclear medicine and molecular imaging.
http://ift.tt/2wa8oTc
Role of interim 18 F-FDG-PET/CT for the early prediction of clinical outcomes of Non-Small Cell Lung Cancer (NSCLC) during radiotherapy or chemo-radiotherapy. A systematic review
Abstract
Background
Non-Small Cell Lung Cancer (NSCLC) is characterized by aggressiveness and includes the majority of thorax malignancies. The possibility of early stratification of patients as responsive and non-responsive to radiotherapy with a non-invasive method is extremely appealing. The distribution of the Fluorodeoxyglucose (18F–FDG) in tumours, provided by Positron-Emission-Tomography (PET) images, has been proved to be useful to assess the initial staging of the disease, recurrence, and response to chemotherapy and chemo-radiotherapy (CRT).
Objectives
In the last years, particular efforts have been focused on the possibility of using ad interim 18F–FDG PET (FDGint) to evaluate response already in the course of radiotherapy. However, controversial findings have been reported for various malignancies, although several results would support the use of FDGint for individual therapeutic decisions, at least in some pathologies. The objective of the present review is to assemble comprehensively the literature concerning NSCLC, to evaluate where and whether FDGint may offer predictive potential.
Methods
Several searches were completed on Medline and the Embase database, combining different keywords. Original papers published in the English language from 2005 to 2016 with studies involving FDGint in patients affected by NSCLC and treated with radiation therapy or chemo-radiotherapy only were chosen.
Results
Twenty-one studies out of 970 in Pubmed and 1256 in Embase were selected, reporting on 627 patients.
Conclusion
Certainly, the lack of univocal PET parameters was identified as a major drawback, while standardization would be required for best practice. In any case, all these papers denoted FDGint as promising and a challenging examination for early assessment of outcomes during CRT, sustaining its predictivity in lung cancer.
http://ift.tt/2iwe9aI
Role of ICG- 99m Tc-nanocolloid for sentinel lymph node detection in cervical cancer: a pilot study
Abstract
Purpose
Sentinel lymph node biopsy (SLNB) can be used for nodal staging in early cervical cancer. For this purpose, the tracers most commonly used are radiotracers based on technetium. For the last decade, indocyanine green (ICG) has been used as a tracer for SLNB in other malignancies with excellent results and, more recently, a combination of ICG and a radiotracer has been shown to have the advantages of both tracers. The aim of this study was to evaluate the role of ICG-99mTc-nanocolloid in SLN detection in patients with cervical cancer.
Methods
This prospective study included 16 patients with cervical cancer. The hybrid tracer was injected the day (19–21 h) before surgery for planar and SPECT/CT lymphoscintigraphy. Blue dye was administered periorificially in 14 patients. SLNs were removed according to their distribution on lymphoscintigraphy and when radioactive, fluorescent and/or stained with blue dye. Nodal specimens were pathologically analysed for metastases including by immunochemistry.
Results
Lymphoscintigraphy and SPECT/CT showed drainage in all patients. A total of 69 SLNs were removed, of which 66 were detected by their radioactivity signal and 67 by their fluorescence signal. Blue dye identified only 35 SLNs in 12 of the 14 patients (85.7%). All patients showed bilateral pelvic drainage. Micrometastases were diagnosed in two patients, and were the only lymphatic nodes involved.
Conclusions
SLNB with ICG-99mTc-nanocolloid is feasible and safe in patients with early cervical cancer. This hybrid tracer provided bilateral SLN detection in all patients and a higher detection rate than blue dye, so it could become an alternative to the combined technique.
http://ift.tt/2iwe5I0
The potential of 223 Ra and 18 F-fluoride imaging to predict bone lesion response to treatment with 223 Ra-dichloride in castration-resistant prostate cancer
Abstract
Purpose
The aims of this study were to calculate bone lesion absorbed doses resulting from a weight-based administration of 223Ra-dichloride, to assess the relationship between those doses and corresponding 18F-fluoride uptake and to assess the potential of quantitative 18F-fluoride imaging to predict response to treatment.
Methods
Five patients received two intravenous injections of 223Ra-dichloride, 6 weeks apart, at 110 kBq/kg whole-body weight. The biodistribution of 223Ra in metastatic lesions as a function of time after administration as well as associated lesion dosimetry were determined from serial 223Ra scans. PET/CT imaging using 18F-fluoride was performed prior to the first treatment (baseline), and at week 6 immediately before the second treatment and at week 12 after baseline.
Results
Absorbed doses to metastatic bone lesions ranged from 0.6 Gy to 44.1 Gy. For individual patients, there was an average factor difference of 5.3 (range 2.5–11.0) between the maximum and minimum lesion dose. A relationship between lesion-absorbed doses and serial changes in 18F-fluoride uptake was demonstrated (r2 = 0.52). A log-linear relationship was demonstrated (r2 = 0.77) between baseline measurements of 18F-fluoride uptake prior to 223Ra-dichloride therapy and changes in uptake 12 weeks after the first cycle of therapy. Correlations were also observed between both 223Ra and 18F-fluoride uptake in lesions (r = 0.75) as well as between 223Ra absorbed dose and 18F-fluoride uptake (r = 0.96).
Conclusions
There is both inter-patient and intra-patient heterogeneity of absorbed dose estimates to metastatic lesions. A relationship between 223Ra lesion absorbed dose and subsequent lesion response was observed. Analysis of this small group of patients suggests that baseline uptake of 18F-fluoride in bone metastases is significantly correlated with corresponding uptake of 223Ra, the associated 223Ra absorbed dose and subsequent lesion response to treatment.
http://ift.tt/2ga6e1S
Scholar : Aging & Mental Health, Volume 21, Issue 11, November 2017 is now available online on Taylor & Francis Online
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Stationary phase-dependent accumulation of ectoine is an efficient adaptation strategy in Vibrio anguillarum against cold stress
Source:Microbiological Research, Volume 205
Author(s): Yue Ma, Qiyao Wang, Wensheng Xu, Xiaohong Liu, Xiating Gao, Yuanxing Zhang
The capability of cold-adaptation is a prerequisite of microorganisms that survive in an environment with frequent fluctuations in temperature. As a global causative agent of vibriosis in marine fish farming, Vibrio anguillarum can efficiently grow and proliferate under cold-stress conditions, which is 15°C lower than the optimal growth temperatures (25–30°C). Our data showed that V. anguillarum was able to synthesize ectoine de novo and that ectoine was essential for its growth under cold stress. Using 1H nuclear magnetic resonance spectroscopy and mutants lacking ectABC and proVWX (ectoine synthesis and transporter system genes, respectively), we confirmed that accumulation of this compatible solute occurs strictly at low temperatures and that the expression of ectA and proV is highly activated in the stationary growth phase. However, the synthesis of ectoine was repressed by exogenous choline (precursor of glycine betaine), suggesting that ectoine is an alternative compatible solute as a cold-stress protectant in V. anguillarum. Based on these results, we present possible scenarios of the synthesis and uptake of ectoine, which will facilitate the understanding of the molecular mechanism of V. anguillarum adaptation to cold environments and help improve freezing-dry processes for the V. anguillarum live vaccine.
http://ift.tt/2wLXaqu
Analysis of the Pho regulon in Streptomyces tsukubaensis
Source:Microbiological Research
Author(s): María Ordóñez-Robles, Fernando Santos-Beneit, Antonio Rodríguez-García, Juan F. Martín
Phosphate regulation of antibiotic biosynthesis in Streptomyces has been studied due to the importance of this genus as a source of secondary metabolites with biological activity. Streptomyces tsukubaensis is the main producer of tacrolimus (or FK506), an immunosuppressant macrolide that generates important benefits for the pharmaceutical market. However, the production of tacrolimus is under a negative control by phosphate and, therefore, is important to know the molecular mechanism of this regulation. Despite its important role, there are no reports about the Pho regulon in S. tsukubaensis. In this work we combined transcriptional studies on the response to phosphate starvation with the search for PHO boxes in the whole genome sequence of S. tsukubaensis. As a result, we identified a set of genes responding to phosphate starvation and containing PHO boxes that include common Pho regulon members but also new species-specific candidates. In addition, we demonstrate for the first time the functional activity of PhoP from S. tsukubaensis through complementation studies in a Streptomyces coelicolor ΔphoP strain. For this purpose, we developed an anhidrotetracycline inducible system that can be applied to the controlled expression of target genes.
http://ift.tt/2vlNcZd
Scholar : Environmental Claims Journal, Volume 29, Issue 3, July 3, 2017 is now available online on Taylor & Francis Online
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Inflammation and the chemical carcinogen benzo[a]pyrene: partners in crime
Publication date: Available online 24 August 2017
Source:Mutation Research/Reviews in Mutation Research
Author(s): Q. Shi, R.W.L. Godschalk, F.J.Van Schooten
Exposure to benzo[a]pyrene (B[a]P) is known to play a role in lung carcinogenesis and the underlying processes can be modified by the presence of inflammation. The inflammatory process can for instance enhance the concentration of reactive metabolites that bind to DNA and may also diminish DNA repair. Additionally, during the inflammatory process mediators are released that create a microenvironment which is suitable for further stimulation of cancer development. Various transcriptional pathways are activated by inflammation, including pathways that are mediated via nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), signal transducer and activator of transcription 3 (STAT-3), and hypoxia-inducible factor-1 (HIF-1). Crosstalk between these pathways and the aryl hydrocarbon receptor (AhR) occurs at multiple levels and thereby boosts B[a]P induced carcinogenesis. This review focuses on inflammatory mediators, including cytokines, chemokines and extracellular enzymes that modulate molecular events in B[a]P induced cancers.
http://ift.tt/2xiiotY
Reductive precipitation and removal of Cr(VI) from groundwaters by pipe flocculation-microfiltration
Abstract
Chromium (Cr(VI)) is a very toxic and carcinogenic element, which is widely present in groundwaters, mainly due to geogenic conditions. The limit of Cr(VI) in drinking water is expected to be reduced to 10 μg/L in both the USA and the European Union. Recent literature findings indicated that the most efficient process in reducing Cr(VI) levels to below 10 μg/L proved to be Cr(VI) reduction by Fe(II), by applying a molar ratio Fe(II)/Cr(VI) of around 9. In the present work, we investigated the reduction of Cr(VI) by Fe(II) in pipe flocculation reactors followed by filtration of insoluble products by microfiltration. The proposed technology involves re-circulation of a part of the sludge in the pipe reactors, in order to improve kinetics and efficiency of the process. The obtained results showed that with a Fe(II) dose of around 1 mg/L, Cr(VI) was reduced to below 10 μg/L, by even an initial concentration as high as 300 μg/L of Cr(VI), corresponding to a molar ratio Fe(II)/Cr(VI) of around 3, thus reducing the overall quantity of reductive reagents and of the produced sludge. This ratio was also confirmed by the XPS analysis, which also showed that Cr(VI) was reduced to Cr(III) and then precipitated either as Cr(OH)3 or associated with the produced iron oxides.
http://ift.tt/2vbwMH4
Efficacy of Extended Adjuvant Therapy with Aromatase Inhibitors in Early Breast Cancer among Common Clinicopathologically-defined Subgroups: A Systematic Review and Meta-analysis
Source:Cancer Treatment Reviews
Author(s): Hadar Goldvaser, Ibrahim AlGorashi, Domen Ribnikar, Bostjan Seruga, Arnoud J. Templeton, Alberto Ocana, Eitan Amir
BackgroundRandomized controlled trials (RCTs) have shown improvements in breast cancer outcomes from extending treatment with aromatase inhibitors (AIs) beyond the initial 5 years after diagnosis. Consistency of this effect in common clinicopathologically defined subgroups was not been reported systematically.MethodsWe identified RCTs comparing extended AIs to placebo or no treatment using a systematic search of MEDLINE and a review of abstracts from key conferences between 2013 and 2016. Hazard ratios (HRs) and 95% confidence intervals (CI) for disease-free survival (DFS) were included in a meta-analysis using generic inverse variance and random effects modelling. Pre-specified subgroups included: age (<60 ±5 years versus ≥60 ±5 years), tumor size (>2cm versus ≤2cm), nodal status (positive versus negative), hormone receptor status (double versus single receptor expression) and receipt of adjuvant chemotherapy (yes versus no).ResultsSeven trials comprising 16,349 patients were analyzed. Overall, the effect of extended AIs was similar in all subgroups. Non-significantly greater effect sizes were seen in patients with larger tumors (HR for DFS 0.77 versus 0.88, p for difference=0.44), nodal involvement (HR=0.72 versus 0.83, p for difference=0.22), double hormone receptor expression (HR=0.68 versus 1.01, p for difference=0.31) and receipt of adjuvant chemotherapy (HR=0.71 versus 0.80, p for difference=0.51).ConclusionsExtended treatment with AIs is associated with similar relative improvements in DFS in all subgroups analyzed. The combination of greater effect size and higher absolute risk of recurrence in node positive and larger tumors will likely translate to higher absolute benefits from extended AIs in these groups.
http://ift.tt/2iuKhvp
Korean red ginseng (Panax ginseng) inhibits obesity and improves lipid metabolism in high fat diet-fed castrated mice
Publication date: Available online 24 August 2017
Source:Journal of Ethnopharmacology
Author(s): Soon Shik Shin, Michung Yoon
Ethnopharmacological relevanceKorean red ginseng (Panax ginseng C.A. Meyer, Araliaceae) has been historically used as a traditional drug for the prevention and treatment of most ageing-related diseases, such as obesity, dyslipidemia, diabetes, and cardiovascular disease. Elderly men with testosterone deficiency are strongly associated with many of the aforementioned metabolic diseases. The aim of this study was to determine the effects of ginseng on obesity and lipid metabolism in a mouse model of testosterone deficiency (castrated C57BL/6J mice).Materials and methodsThe effects of ginseng extract (GE) on obesity and lipid metabolism in high-fat diet (HFD)-fed castrated C57BL/6J mice were examined using hematoxylin and eosin staining, serum lipid analysis, and quantitative real-time polymerase chain reaction (PCR). The effects of GE, ginsenosides, and testosterone on adipogenesis were measured using Oil Red O staining, XTT assay, and real-time PCR.ResultsCompared with HFD mice, mice receiving HFD supplemented with GE (HFD-GE) for 8 weeks showed decreased body weight, adipose tissue mass, and adipocyte size without affecting food intake. Serum levels of triglycerides and total cholesterol were lowered in HFD-GE mice than in HFD mice. GE also markedly reduced HFD-induced hepatic lipid accumulation. Concomitantly, HFD-GE decreased mRNA expression of adipogenesis-related genes (SREBP-1C, PPARγ, FAS, SCD1, and ACC1) in visceral adipose tissues compared with HFD alone. Consistent with the in vivo data, GE and major active ginsenosides (Rb1 and Rg1) decreased lipid accumulation and mRNA expression of PPARγ, C/EBPα, and SCD1 in 3T3-L1 adipocytes compared with control. Similarly, testosterone also decreased lipid accumulation and mRNA levels of PPARγ, C/EBPα, and SCD1. These inhibitory effects were further increased by co-treatment of GE or ginsenosides with testosterone.ConclusionsOur results demonstrate that ginseng can inhibit obesity and dyslipidemia in HFD-fed castrated mice, possibly by inhibiting adipogenic gene expression. In addition, our results indicate that ginseng may act like testosterone to inhibit adipogenesis, suggesting that ginseng may be able to prevent obesity, hyperlipidemia, and hepatic steatosis in men with testosterone deficiency.
Graphical abstract
http://ift.tt/2wtkZ6A
Antioxidant, anti-inflammatory, antiproliferative and antimycobacterial activities of the essential oil of Psidium guineense Sw. and spathulenol
Publication date: Available online 24 August 2017
Source:Journal of Ethnopharmacology
Author(s): Kamilla Felipe do Nascimento, Flora Martinez Figueira Moreira, Joyce Alencar Santos, Candida Aparecida Leite Kassuya, Julio Henrique Rosa Croda, Claudia Andrea Lima Cardoso, Maria do Carmo Vieira, Ana Lúcia Tasca Góis Ruiz, Mary Ann Foglio, João Ernesto de Carvalho, Anelise Samara Nazari Formagio
Ethnopharmacological relevanceLeaves from Psidium guineense Sw. are used in popular medicine for the treatment of inflammatory disease. However, there is no scientific evidence demonstrating this activity.Aim of the studyTo evaluate the antioxidant, anti-inflammatory, antiproliferative and antimycobacterial activities of the essential oil of P. guineense and spathulenol (a major constituent). The study was conducted in part to provide evidence supporting the ethnobotanical use of the leaves of this species.Material and methodsThe essential oil (EOPG) was extracted from the leaves of P. guineense by hydrodistillation and analysed by gas chromatography-mass spectrometry (GC–MS). The major compound, spathulenol (PG-1), was isolated in a chromatographic column and characterized by nuclear magnetic resonance (NMR). EOPG and PG-1 were evaluated in vitro for antioxidant activity by DPPH, ABTS and MDA methods; anti-inflammatory potential was assessed using two models, including pleurisy and edema, in mice. The impact of EOPG and PG-1 on cell proliferation was determined via spectrophotometric quantification of the cellular protein content using a sulforhodamine B assay, and anti-Mycobacterium tuberculosis activity was determined using the REMA method.ResultsA total of 38 components were identified from the EOPG, with the sesquiterpenic alcohol spathulenol (PG-1) (80.7%) being the major constituent. EOPG and PG-1 exhibited the highest antioxidant activities in the DPPH and MDA system compared with reference standard, with IC50 values ranging from 26.13–85.60μg/mL. Oral administration of EOPG and PG-1 showed significant inhibition in the Cg-induced mice paw oedema and pleurisy model. The EOPG (GI50 = 0.89μg/mL) and PG-1 (GI50 = 49.30μg/mL) were particularly effective against the ovarian cancer cell line. Both showed moderate antimycobacterial activity.ConclusionFor the first time, this study demonstrated the antioxidant, anti-inflammatory, antiproliferative and antimycobacterial properties of the essential oil of P. guineense (leaves were collected in Dourados-MS) and spathulenol, collaborating the etnhopharmacologycal use of this plant due to its an anti-inflammatory effect.
Graphical abstract
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Identification of patients with localized Ewing sarcoma at higher risk for local failure: A report from the Children’s Oncology Group
Publication date: Available online 24 August 2017
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): Safia K. Ahmed, R. Lor Randall, Steven G. DuBois, William S. Harmsen, Mark Krailo, Karen J. Marcus, Katherine A. Janeway, David S. Geller, Joel I. Sorger, Richard B. Womer, Linda Granowetter, Holcombe E. Grier, Richard G. Gorlick, Nadia N.I. Laack
PurposeTo identify clinical and treatment variables associated with a higher risk of local failure in Ewing sarcoma patients treated on recent Children's Oncology Group protocols.Methods and MaterialsData for 956 patients treated with ifosfamide and etoposide based chemotherapy on INT-0091, INT-0154, and AEWS0031 were analyzed. Local treatment modalities were defined as surgery, definitive radiotherapy (RT), or surgery+radiation (S+RT). Five-year cumulative incidence of local failure was determined.ResultsThe local failure rate for the entire cohort was 7.3%, with a 3.9% rate for surgery, 15.3% for RT (p<0.01), and 6.7% for S+RT (p=0.12). The local failure incidence was 5.4% for extremity tumors, 13.2% for pelvis tumors (p<0.01), 5.3% for axial non-spine tumors (p=0.90), 9.1% for extraskeletal tumors (p=0.08), and 3.6% for spine tumors (p=0.49). The incidence of local failure was 14.8% for extremity tumors and 22.4% for pelvis tumors treated with RT, compared to 3.7% for extremity tumors and 3.9% for pelvis tumors treated with surgery (p≤0.01). There was no difference in local failure incidence by local treatment modality for axial non-spine, spine, and extraskeletal tumors. The local failure incidence was 11.9% in patients ≥18 years versus 6.7% in patients <18 years (p=0.02). Age ≥18 years (Hazard ratio 1.9, p=0.04) and treatment with RT (Hazard ratio 2.40, p<0.01) remained independent prognostic factors for higher local failure incidence on multivariate analysis. Tumor size (</≥ 8 centimeters) was available in 40% of patients and did not correlate with local failure incidence.ConclusionsLocal tumor control is excellent and similar between surgery and RT for axial non-spine, spine, and extraskeletal tumors. Age ≥18 years and use of RT, primarily for pelvis and extremity tumors, are associated with the highest risk of local failure. Further efforts should focus on improving outcomes for these patients.
Teaser
Our analysis of local tumor control outcomes in 956 Ewing sarcoma patients demonstrates age ≥18 years and use of definitive radiotherapy, primarily for pelvis and extremity tumors, are associated with the highest risk of local failure. Local tumor control is excellent and similar between surgery and definitive radiotherapy for axial non-spine, spine, and soft tissue extraskeletal tumors.http://ift.tt/2wtqan1
Radiotherapy deficiencies identified during on-site dosimetry visits by the IROC Houston QA Center
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): Stephen F. Kry, Lainy Dromgoole, Paola Alvarez, Jessica Leif, Andrea Molineu, Paige Taylor, David S. Followill
PurposeTo review the dosimetric, mechanical, and programmatic deficiencies most frequently observed during on-site visits of radiotherapy facilities by the Imaging and Radiation Oncology Core Houston office (IROC Houston).MethodsIROC Houston's findings between 2000 and 2014, including 409 institutions and 1020 linacs, were compiled. IROC Houston's on-site evaluation includes verification of absolute calibration (tolerance of ±3%), relative dosimetric review (tolerances of ±2% between TPS calculation and measurement), mechanical evaluation (including MLC and kV-MV evaluation against TG-142 tolerances), and general programmatic review (including institutional QA program versus TG-40 and TG-142).ResultsAn average of 3.1 deficiencies was identified at each institution visited, a number that has decreased slightly with time. The most common errors are tabulated, and include TG-40/TG-142 compliance (82% of institutions were deficient), small field size output factors (59% of institutions had errors ≥3%), and wedge factors (33% of institutions had errors ≥3%). Dosimetric errors of ≥10%, including in beam calibration, were seen at many institutions.ConclusionsThere is substantial room for improvement of both dosimetric and programmatic issues in radiotherapy, which should be a high priority for the medical physics community. Particularly relevant was suboptimal beam modeling in the treatment planning system and a corresponding failure to detect these errors by not including TPS data in the linac QA process.
Teaser
IROC Houston on-site visits of radiotherapy facilities includes an evaluation of beam calibration, relative dosimetry, mechanical checks, and other programmatic issues. The deficiencies identified over the past 15 years are compiled in this study, highlighting areas where problems are most often found (e.g., small field output factors, wedge factors, calibration, etc.). These areas should receive particular attention during beam modeling and machine QA by medical physicists to ensure optimal accuracy is achieved.http://ift.tt/2wa7ExD
Hospital quality factors influencing the mobility of patients for radical prostate cancer radiotherapy: a national population based study
Publication date: Available online 24 August 2017
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): Ajay Aggarwal, Daniel Lewis, Arunan Sujenthiran, Susan C. Charman, Richard Sullivan, Heather Payne, Malcolm Mason, Jan van der Meulen
IntroductionPatient choice policies have been introduced across publicly funded health systems to give patients more control over their care, and to encourage quality improvement amongst providers. To date we have no empirical evidence that patients requiring radiation treatment are prepared to travel to alternative more distant centres or the factors that influence this.Materials and MethodsWe present the results of a national cohort study using administrative hospital data for all 44,363 men who were diagnosed with prostate cancer and underwent radical radiotherapy in the English National Health Service between 2010 and 2014. Using geographic information systems we investigated the extent to which men choose to travel beyond ("bypass") their nearest radiotherapy centre and conditional logistic regression to estimate the effect of hospital and patient characteristics on this mobility.Results20.7% (n= 9,161) of men bypassed their nearest radiotherapy centre. Travel time had a very strong impact on where patients moved to for their treatment, but its effect was smaller for men who were younger, more affluent, and from rural areas (p for interaction always <0·001). Men were prepared to travel further to hospitals that offered hypofractionated prostate radiotherapy as their standard schedule (odds ratio 3.19, p<0.001), to large-scale radiotherapy units (odds ratio 1.56 P<0.001) and to hospitals that were early adopters of intensity modulated radiotherapy (odds ratio 1.37, p<0.001).ConclusionMen with prostate cancer are prepared to bypass their nearest radiotherapy centres. They are more likely to travel to larger established centres and those that offer innovative technology and more convenient radiotherapy schedules. Indicators, which accurately reflect the quality of radiotherapy delivered are needed to guide patients' choices for radiotherapy treatment. In their absence, patient mobility may negatively affect the efficiency and capacity of a regional or national radiotherapy service and offer perverse incentives for technology adoption.
Teaser
Using geographic information systems and econometric modelling we present the first national study evaluating the hospital quality factors that attract patients for radiotherapy treatment in health-care markets. We found that one in five men bypassed their nearest radiotherapy centre for treatment, especially those who were younger, and more affluent. In the absence of indicators reflecting treatment quality, centres that were early adopters of intensity modulated radiotherapy or that offered shorter hypofractionated treatment schedules were more attractive to patients.http://ift.tt/2wtAJGZ
Feasibility of pencil beam scanned Intensity Modulated Proton Therapy in breath-hold for locally-advanced non-small cell lung cancer
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): Jenny Gorgisyan, Per Munck af Rosenschold, Rosalind Perrin, Gitte F. Persson, Mirjana Josipovic, Maria Francesca Belosi, Svend Aage Engelholm, Damien C. Weber, Antony J. Lomax
PurposeThe feasibility of treating patients with locally-advanced non-small cell lung cancer (NSCLC) with pencil beam scanned intensity modulated proton therapy (IMPT) in breath-hold has been evaluated.Methods and MaterialsFifteen NSCLC patients previously treated to 66 Gy in 33 fractions with image-guided photon radiation therapy were included in this simulation study. In addition to a planning breath-hold CT scan prior to treatment start, six (median, range: 3-9) breath-hold CT scans per patient were acquired prospectively, throughout the course of the radiation therapy. Three field IMPT treatment plans were constructed based on the planning breath-hold CT scan and the 4D dose distributions were simulated, taking both the intra- and inter-fractional motion of the patient into account, in addition to the dynamic treatment delivery.ResultsThe median clinical target volume (CTV) V95% (the volume receiving 95% of the prescribed dose) was 99.8% and 99.7% for the planned and simulated dose distributions, respectively. For three patients (20%), the dose degradation was more than 5% and plan adjustment was needed. Dose degradation was significantly correlated to the change in water-equivalent path lengths (WEPL) (p<0.01) in terms of percentage of voxels with 3 mm undershoot on repeat CTs. The dose to the organs at risk was similar for planned and simulated dose distributions. Three or less breath-holds per field would be required for 12/15 patients, which is clinically feasible.ConclusionsFor 9/15 NSCLC patients, IMPT in breath-hold was both dosimetrically robust and feasible to deliver regarding the treatment time. Three patients would require plan adaption to meet the dosimetric criteria. WEPL is an indicator of plan robustness and should be considered for selection of patients for which the plan would require adaptation.
http://ift.tt/2w9MQpI
Recommendations for the optimal radiation dose in patients with primary cutaneous anaplastic large cell lymphoma: A report of the Dutch Cutaneous Lymphoma Group
Publication date: Available online 24 August 2017
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): Rutger C. Melchers, Rein Willemze, Laurien A. Daniëls, Karen J. Neelis, Marcel W. Bekkenk, Ellen R.M. de Haas, Barbara Horvath, Michelle M. van Rossum, Cornelus J.G. Sanders, Berit Velstra, Joep C.J.M. Veraart, Rachel E.J. Roach, Maarten H. Vermeer, Koen D. Quint
ObjectiveTo determine the optimal radiation dose for treatment of primary cutaneous anaplastic large cell lymphoma (C-ALCL) with solitary or localized, multifocal or recurrent skin lesions.Materials and MethodsIn this multicenter study, patients with C-ALCL, who had been treated with radiotherapy (RT) between 1984 and 2016, were retrieved from the Dutch registry of cutaneous lymphomas. Distinction was made between patients first presenting with solitary or localized (n=63), with multifocal skin lesions (n=6), and patients with a skin relapse (n=22). Radiation doses, treatment response and follow-up were evaluated. Radiation doses were categorized in low-dose (≤20 Gy), intermediate dose (21-39 Gy) and high-dose (≥40 Gy).Results61/63 (97%) patients presenting with solitary or localized skin lesions showed a complete response (CR). There were no differences in CR between low-dose (16/17), intermediate dose (15/15) and high-dose RT (30/31). After a median follow-up of 46 months, 30 of 63 (48%) patients had a relapse, but infield relapses were never observed. Six out of 6 (100%) patients initially presenting with multifocal skin lesions showed a CR (3/3 low-dose, 2/2 intermediate dose, 1/1 high-dose). After a median follow-up of 27 months, 3 of 6 patients had a relapse. Treatment of 33 skin relapses in 22 patients showed no differences in CR between low-dose (18/19), intermediate dose (6/6) and high-dose radiotherapy (8/8).In the last ten years there has been a decrease in radiation dose used in the treatment of C-ALCL. Treatment of multifocal and recurrent lesions with a dose of 8 Gy (2x4 Gy) resulted in CR of 17/18 lesions.ConclusionOur results show that a radiation dose of 20 Gy (8x2.5 Gy) is effective in patients presenting with solitary or localized skin lesions. For patients with multifocal skin lesions and patients with a skin relapse, a dose of 8 Gy (2x4 Gy) may be sufficient.
Teaser
Radiotherapy is the first choice of treatment in primary cutaneous anaplastic large cell lymphoma (C-ALCL), but the optimal dose has yet to be defined. Based on the evaluation of 114 radiation fields in 78 C-ALCL patients, we recommend a dose of 20 Gy for the initial treatment of solitary or localized skin lesions and a dose of 8 Gy for initial treatment of multifocal lesions and for recurrent lesions.http://ift.tt/2wtZO4s
Treatment-related non-contiguous radiologic changes in children with diffuse intrinsic pontine glioma treated with expanded irradiation fields and antiangiogenic therapy
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): Zoltan Patay, Thomas E. Merchant, Rosa Nguyen, Christopher R. Pierson, Arzu Onar-Thomas, Alberto Broniscer
Among 23 children with diffuse intrinsic pontine glioma who were treated with small-molecule inhibitors and expanded-field local RT, we observed a high incidence of non-contiguous treatment-related abnormalities (NCTRAs) in the brain. On the basis of their imaging features and patterns, we speculate that NCTRA development was secondary to synergistic steno-occlusive vascular effects induced by the combination of expanded clinical target volume RT, potent antiangiogenic therapy, young age, and in one case, possibly a genetic predisposition.
http://ift.tt/2wa782J
Unknown Primary Squamous Cell Carcinoma of the Neck
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): Kristen J. Otto, Jimmy J. Caudell
http://ift.tt/2wtBOP0
Imaging Findings within the first 12 months of Hepatocellular Carcinoma treated with Stereotactic Body Radiation Therapy (SBRT)
Source:International Journal of Radiation Oncology*Biology*Physics
Author(s): Mishal Mendiratta-Lala, Everett Gu, Dawn Owen, Kyle C. Cuneo, Latifa Bazzi, Theodore S. Lawrence, Hero K. Hussain, Matthew S. Davenport
PurposeTo correlate the imaging findings of treated hepatocellular carcinoma (HCC) post stereotactic body radiation therapy (SBRT) with explant pathology and alpha-fetoprotein (AFP) response.MethodsFrom 2007-2015, of 146 patients treated with liver SBRT for Barcelona Clinic Liver Cancer (BCLC) Stage A hepatocellular carcinoma, 10 were identified with inclusion criteria and hadregular interval follow up MRI/triple phase CT and explant pathology or declining AFP values for radiology-pathology response correlation. Reference standards for successful response were: >90% necrosis on explant pathology or pre-treatment AFP >75 ng/mL normalizing to <10 ng/mL within 1 year post-SBRT without other treatment. Subjects were treated with 24-50 Gy in 3-5 fractions. Multiphasic MRI or CT was performed at 3, 6, 9 and 12 months post-SBRT was compared to pre-treatment imaging by two expert radiologists. Descriptive statistics were calculated.ResultsThere were 10 subjects with 10 treated HCCs, classified as 3 OPTN 5a, 4 OPTN 5b, and 3 OPTN 5x. All had successfully treated HCCs, based on explant pathology or declining AFP. Four of 10 HCCs had persistent central arterial hyperenhancement 3-12 months post-SBRT; persistent washout was common up to 12 months (9/10). 9/10 treated HCCs exhibited decreased size at 12 months. Liver parenchyma adjacent to the lesion showed early (3-6 months) hyperemia followed by late (6-12 months) capsular retraction and delayed enhancement. No patient had a significant decline in liver function.ConclusionIn the absence of increasing size, persistent central arterial hyperenhancement and washout can occur within the first 12 months post-SBRT in successfully treated HCCs, and may not represent residual viable tumor. Liver parenchyma adjacent to the treated lesion showed inflammation followed by fibrosis, without significant change in hepatic function. Until a radiological signature of tumor control is determined, freedom from local progression appears to be the best measure of HCC control after SBRT
Teaser
In the absence of increasing size, persistent arterial hyperenhancement with washout can occur within the first 12 months post-SBRT in successfully treated HCCs, and should not be confused with residual tumor. Liver parenchyma adjacent to the treated lesion showed inflammation followed by fibrosis, without significant change in hepatic function. Until a radiological signature of tumor control is determined, freedom from local progression appears to be the best measure of HCC control after SBRT.http://ift.tt/2w9NJ1D
Πέμπτη 24 Αυγούστου 2017
In situ observation on temperature dependence of martensitic transformation and plastic deformation in superelastic NiTi shape memory alloy
Publication date: 15 November 2017
Source:Materials & Design, Volume 134
Author(s): Yao Xiao, Pan Zeng, Liping Lei, Yanzhi Zhang
In situ digital image correlation (DIC) and in situ X-ray diffraction (XRD) are applied to investigate the effect of temperature on martensitic transformation and plastic deformation in superelastic NiTi shape memory alloy. Via in situ DIC, two well-known deformation modes of NiTi are identified at various temperatures: (A) localized forward and reverse transformations with little residual strain (<1%); (B) localized forward transformation and homogenous reverse transformation with considerable residual strain (>1%). As temperature increases from 25°C to 120°C, the mechanical response of NiTi gradually transits from Type A to Type B. We verify that plastic strain accumulates concurrently as the traverse of the front of localized deformation band. Via in situ XRD observation, we conclude that it is material plasticity rather than retained martensite that plays a dominant role in the irreversibility of NiTi. The experimental results provide both macroscopic and lattice level scenarios to understand the temperature dependence of complicated thermomechanical coupling and plasticity in superelastic NiTi.
Graphical abstract
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Fabrication of poly (vinyl alcohol)/graphene nanocomposite foam based on solid state shearing milling and supercritical fluid technology
Publication date: 15 November 2017
Source:Materials & Design, Volume 134
Author(s): Pengju Liu, Wenhua Chen, Yingbin Jia, Shibing Bai, Qi Wang
Combining the nanocomposite and supercritical fluid (SCF) foaming technology develops an effective preparation method for new class of microcellular polymer nanocomposite foam, which has received much attention in both research and practice. In this paper, the poly (vinyl alcohol) (PVA)/graphene nanocomposites were successfully prepared at ambient temperature through the solid state shear milling technique, and made into foam material by using supercritical carbon dioxide as the physical blowing agent. The results indicated that graphene sheets were uniformly incorporated into the PVA matrix after milling, and graphene sheets did not reaggregate in the subsequent melting process. These well-dispersed PVA/graphene nanocomposites presented significant increases in tensile strength and thermal behavior compared to pure PVA. In the SCF foaming procedure, graphene sheets acted as the heterogeneous sites to facilitate the bubble nucleation process. More importantly, the embedded graphene sheets played an effective role of reinforcing the cell walls to stabilize the cellular structure during the cell growth stage, thus compressive properties of the nanocomposite foams were significantly enhanced. The bubbles tended to be elongated along the direction of CO2 decompression at a relatively high foaming temperature and with fast depressurization rate.
Graphical abstract
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Structure and properties of silkworm cocoon (Bombyx mori) treated by hot pressing
Publication date: 15 November 2017
Source:Materials & Design, Volume 134
Author(s): Tao Wang, Lanlan Chen, Lingmei Du, Tingting Shen, Fei Li, Lan Huang, Zhi Li, Dayang Wu
The silkworm cocoon has outstanding mechanical properties due to the specific composite structure. However, the individual cocoon is small and irregular in shape which dramatically hinders its application in artificial composites. Here, rectangular pieces of silkworm cocoons were cut and combined into large sheets by means of hot pressing. The structure and properties of compressed cocoon pieces were investigated. The thickness and porosity of pieces are significantly decreased at the high pressure, besides silk fibers are more deformed and bonded at high temperature cause of sericin's softening and fusion. Tensile strength and modulus are remarkably increased compared to those of the raw cocoon, and so do the interlayer bonding. The stable thermal property of the compressed cocoons demonstrates that compression at a high temperature has little harm to cocoons. Therefore, hot pressing is a practical way to build artificial cocoon composites for engineering applications.
Graphical abstract
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Effect of hatch length on the development of microstructure, texture and residual stresses in selective laser melted superalloy Inconel 718
Publication date: 15 November 2017
Source:Materials & Design, Volume 134
Author(s): Naresh Nadammal, Sandra Cabeza, Tatiana Mishurova, Tobias Thiede, Arne Kromm, Christoph Seyfert, Lena Farahbod, Christoph Haberland, Judith Ann Schneider, Pedro Dolabella Portella, Giovanni Bruno
In the present study, samples fabricated by varying the deposition hatch length during selective laser melting of nickel based superalloy Inconel 718 were investigated. Microstructure and texture of these samples was characterized using scanning electron microscopy, combined with electron back-scattered diffraction, and residual stress assessment, using neutron diffraction method. Textured columnar grains oriented along the sample building direction were observed in the shorter hatch length processed sample. A ten-fold increase in the hatch length reduced the texture intensity by a factor of two attributed to the formation of finer grains in the longer hatch length sample. Larger gradients of transverse residual stress in the longer hatch length sample were also observed. Along the build direction, compressive stresses in the shorter hatch length and negligible stresses for the longer hatch length specimen were observed. Changes to the temperature gradient (G) in response to the hatch length variation, influenced the G to growth rate (R) ratio and the product G×R, in agreement with the microstructures and textures formed. For the residual stress development, geometry of the part also played an important role. In summary, tailored isotropy could be induced in Inconel 718 by a careful selection of parameters during selective laser melting.
Graphical abstract
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Factors associated with routine childhood vaccine uptake and reasons for non-vaccination in India: 1998–2008
Source:Vaccine
Author(s): Mark Rohit Francis, Hanna Nohynek, Heidi Larson, Vinohar Balraj, Venkata Raghava Mohan, Gagandeep Kang, J. Pekka Nuorti
BackgroundDespite almost three decades of the Universal Immunization Program in India, a little more than half the children aged 12–23months receive the full schedule of routine vaccinations. We examined socio-demographic factors associated with partial-vaccination and non-vaccination and the reasons for non-vaccination among Indian children during 1998 and 2008.MethodsData from three consecutive, nationally-representative, District Level Household and Facility Surveys (1998–99, 2002–04 and 2007–08) were pooled. Multinomial logistic regression was used to identify individual and household level socio-demographic variables associated with the child's vaccination status. The mother's reported reasons for non-vaccination were analyzed qualitatively, adapting from a previously published framework.ResultsThe pooled dataset contained information on 178,473 children 12–23months of age; 53%, 32% and 15% were fully vaccinated, partially vaccinated and unvaccinated respectively. Compared with the 1998–1999 survey, children in the 2007–2008 survey were less likely to be unvaccinated (Adjusted Prevalence Odds Ratio (aPOR): 0.92, 95%CI=0.86–0.98) but more likely to be partially vaccinated (aPOR: 1.58, 95%CI=1.52–1.65). Vaccination status was inversely associated with female gender, Muslim religion, lower caste, urban residence and maternal characteristics such as lower educational attainment, non-institutional delivery, fewer antenatal care visits and non-receipt of maternal tetanus vaccination. The mother's reported reasons for non-vaccination indicated gaps in awareness, acceptance and affordability (financial and non-financial costs) related to routine vaccinations.ConclusionsPersisting socio-demographic disparities related to partial-vaccination and non-vaccination were associated with important childhood, maternal and household characteristics. Further research investigating the causal pathways through which maternal and social characteristics influence decision-making for childhood vaccinations is needed to improve uptake of routine vaccination in India. Also, efforts to increase uptake should address parental fears related to vaccination to improve trust in government health services as part of ongoing social mobilization and communication strategies.
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Vaccine exemptions and the kindergarten vaccination coverage gap
Source:Vaccine
Author(s): Philip J. Smith, Jana Shaw, Ranee Seither, Adriana Lopez, Holly A. Hill, Mike Underwood, Cynthia Knighton, Zhen Zhao, Megha Shah Ravanam, Stacie Greby, Walter A. Orenstein
BackgroundVaccination requirements for kindergarten entry vary by state, but all states require 2 doses of measles containing vaccine (MCV) at kindergarten entry.ObjectiveTo assess (i) national MCV vaccination coverage for children who had attended kindergarten; (ii) the extent to which undervaccination after kindergarten entry is attributable to parents' requests for an exemption; (iii) the extent to which undervaccinated children had missed opportunities to be administered missing vaccine doses among children whose parent did not request an exemption; and (iv) the vaccination coverage gap between the "highest achievable" MCV coverage and actual MCV coverage among children who had attended kindergarten.MethodsA national survey of 1465 parents of 5–7year-old children was conducted during October 2013 through March 2014. Vaccination coverage estimates are based provider-reported vaccination histories. Children have a "missed opportunity" for MCV if they were not up-to-date and if there were dates on which other vaccines were administered but not MCV. The "highest achievable" MCV vaccination coverage rate is 100% minus the sum of the percentages of (i) undervaccinated children with parents who requested an exemption; and (ii) undervaccinated children with parents who did not request an exemption and whose vaccination statuses were assessed during a kindergarten grace period or period when they were provisionally enrolled in kindergarten.ResultsAmong all children undervaccinated for MCV, 2.7% were attributable to having a parent who requested an exemption. Among children who were undervaccinated for MCV and whose parent did not request an exemption, 41.6% had a missed opportunity for MCV. The highest achievable MCV coverage was 98.6%, actual MCV coverage was 90.9%, and the kindergarten vaccination gap was 7.7%.ConclusionVaccination coverage may be increased by schools fully implementing state kindergarten vaccination laws, and by providers assessing children's vaccination status at every clinic visit, and administering missed vaccine doses.
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Evaluation of the RumiWatchSystem for measuring grazing behaviour of cows
Source:Journal of Neuroscience Methods
Author(s): J. Werner, L. Leso, C. Umstatter, J. Niederhauser, E. Kennedy, A. Geoghegan, L. Shalloo, M. Schick, B. O'Brien
Feeding behaviour is an important parameter of animal performance, health and welfare, as well as reflecting levels and quality of feed available. Previously, sensors were only used for measuring animal feeding behaviour in indoor housing systems. However, sensors such as the RumiWatchSystem can also monitor such behaviour continuously in pasture-based environments. Therefore, the aim of this study was to validate the RumiWatchSystem to record cow activity and feeding behaviour in a pasture-based system. The RumiWatchSystem was evaluated against visual observation across two different experiments. The time duration per hour at grazing, rumination, walking, standing and lying recorded by the RumiWatchSystem was compared to the visual observation data in Experiment 1. Concordance Correlation Coefficient (CCC) values of CCC=0.96 for grazing, CCC=0.99 for rumination, CCC=1.00 for standing and lying and CCC=0.92 for walking were obtained. The number of grazing and rumination bouts within one hour were also analysed resulting in Cohen's Kappa (κ)=0.62 and κ=0.86 for grazing and rumination bouts, respectively. Experiment 2 focused on the validation of grazing bites and rumination chews. The accordance between visual observation and automated measurement by the RumiWatchSystem was high with CCC=0.78 and CCC=0.94 for grazing bites and rumination chews, respectively. These results indicate that the RumiWatchSystem is a reliable sensor technology for observing cow activity and feeding behaviour in a pasture based milk production system, and may be used for research purposes in a grazing environment.
http://ift.tt/2xijlSP
Effects of a combination of 3,4-methylenedioxymeth amphetamine and caffeine on real time stimulated dopamine release in the rat striatum: studies using fast cyclic voltammetry
Source:Journal of Neuroscience Methods
Author(s): J.J. O'Connor, K.M. O'Boyle, J.P. Lowry
It is well documented that caffeine exacerbates the hyperthermia associated with acute exposure to 3,4-methylenedioxymethamphetamine (MDMA) in rats. Previous reports have also indicated that MDMA-related enhancement of dopamine release is exacerbated in the presence of caffeine. In the present study we have examined whether the effects of MDMA on real-time stimulated dopamine release in the absence of uptake inhibition are accentuated in the presence of caffeine. Isolated striatal slices from adult male Wistar rats were treated acutely with MDMA, caffeine, or a combination, and their effects on single and 5pulse stimulated dopamine release monitored using the technique of fast cyclic voltammetry. Caffeine at 10 or 100μM had no significant effect on single pulse stimulated dopamine release. However 100μM caffeine caused a significant peak increase in 5pulse stimulated dopamine release. Both 1 and 30μM MDMA gave rise to a significant increase in both single and 5-pulse dopamine release and reuptake. A combination of 100μM caffeine and 1 or 30μM MDMA did not significantly enhance the effects of MDMA on single or 5pulse dopamine release and reuptake when compared to that applied alone. Utilizing single action potential dependent dopamine release, these results do not demonstrate a caffeine-enhanced MDMA-induced dopamine release.
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Development of a head-mounted wireless microstimulator for deep brain stimulation in rats
Source:Journal of Neuroscience Methods
Author(s): Felix Fluri, Thomas Mützel, Michael K. Schuhmanna, Miloš Krstić, Heinz Endres, Jens Volkmann
BackgroundCommercial neurostimulators for clinical use are effective in patients; however they are too large and prohibitively expensive for preclinical studies. Thus, there is an urgent need of a small inexpensive and wireless microstimulator which is fully programmable in frequency, pulse width and amplitude for rodent experiments.New methodsRats were subjected to a photothrombotic stroke of the right sensorimotor cortex and a microelectrode was implanted in the right mesencephalic locomotor region. The microstimulator was connected with the head plug of the rat. Three different stimulation frequencies were applied and different stimulating amplitudes were chosen. Under these conditions, gait velocity and locomotor behavior of six rats were examined on a beam.ResultsThe head-mounted microstimulator allowed freedom in all motor activities performed spontaneously by the tested rats. Increasing either the frequency or the stimulating amplitude increased gait velocity and ameliorated locomotor behavior after stroke.Comparison with existing methodsOther devices for DBS in rodents must be implanted under the skin or worn in an animal jacket on the back by the tested rat. Some available systems require even a tethering of the tested animal via a cable to an external stimulation system, which limits the freedom of movement.ConclusionHere, we present a freely programmable microstimulator including DBS-typical stimulating parameters. The lightweight device is connected by a simple plug to the head allowing full freedom of movement and exchange of batteries for long-term experiments. The design of this stimulator is suitable for sophisticated behavior tests requiring balance and skilled walking.
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Metabolic, Epigenetic, and Transgenerational Effects of Gut Bacterial Choline Consumption
Publication date: Available online 24 August 2017
Source:Cell Host & Microbe
Author(s): Kymberleigh A. Romano, Ana Martinez-del Campo, Kazuyuki Kasahara, Carina L. Chittim, Eugenio I. Vivas, Daniel Amador-Noguez, Emily P. Balskus, Federico E. Rey
Choline is an essential nutrient and methyl donor required for epigenetic regulation. Here, we assessed the impact of gut microbial choline metabolism on bacterial fitness and host biology by engineering a microbial community that lacks a single choline-utilizing enzyme. Our results indicate that choline-utilizing bacteria compete with the host for this nutrient, significantly impacting plasma and hepatic levels of methyl-donor metabolites and recapitulating biochemical signatures of choline deficiency. Mice harboring high levels of choline-consuming bacteria showed increased susceptibility to metabolic disease in the context of a high-fat diet. Furthermore, bacterially induced reduction of methyl-donor availability influenced global DNA methylation patterns in both adult mice and their offspring and engendered behavioral alterations. Our results reveal an underappreciated effect of bacterial choline metabolism on host metabolism, epigenetics, and behavior. This work suggests that interpersonal differences in microbial metabolism should be considered when determining optimal nutrient intake requirements.
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Teaser
The gut microbiota is a dynamic metabolic organ associated with host health and disease phenotypes. Romano, Martinez-del Campo et al. report that choline-consuming gut bacteria reduce the bioavailability of this essential nutrient and deplete methyl-donor metabolites, resulting in alterations to host epigenetic programming and increased susceptibility to metabolic disease.http://ift.tt/2gaTmsx
An Oxidative Central Metabolism Enables Salmonella to Utilize Microbiota-Derived Succinate
Publication date: Available online 24 August 2017
Source:Cell Host & Microbe
Author(s): Luisella Spiga, Maria G. Winter, Tatiane Furtado de Carvalho, Wenhan Zhu, Elizabeth R. Hughes, Caroline C. Gillis, Cassie L. Behrendt, Jiwoong Kim, Daniela Chessa, Helene L. Andrews-Polymenis, Daniel P. Beiting, Renato L. Santos, Lora V. Hooper, Sebastian E. Winter
The mucosal inflammatory response induced by Salmonella serovar Typhimurium creates a favorable niche for this gut pathogen. Conventional wisdom holds that S. Typhimurium undergoes an incomplete tricarboxylic acid (TCA) cycle in the anaerobic mammalian gut. One change during S. Typhimurium-induced inflammation is the production of oxidized compounds by infiltrating neutrophils. We show that inflammation-derived electron acceptors induce a complete, oxidative TCA cycle in S. Typhimurium, allowing the bacteria to compete with the microbiota for colonization. A complete TCA cycle facilitates utilization of the microbiota-derived fermentation product succinate as a carbon source. S. Typhimurium succinate utilization genes contribute to efficient colonization in conventionally raised mice, but provide no growth advantage in germ-free mice. Mono-association of gnotobiotic mice with Bacteroides, a major succinate producer, restores succinate utilization in S. Typhimurium. Thus, oxidative central metabolism enables S. Typhimurium to utilize a variety of carbon sources, including microbiota-derived succinate.
Graphical abstract
Teaser
Spiga et al. show that during colonization of the intestinal lumen, the enteric pathogen S. Typhimurium performs a complete TCA cycle. This oxidative central metabolism enables S. Typhimurium to utilize the microbiota-derived fermentation product succinate as a nutrient and to compete with the microbiota for colonization of the intestinal tract.http://ift.tt/2gatehA
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Ειδοποίηση Μελετητή:[ ωτα ] [HTML] Gender, identity and material: Film screening C Brand - 2017 ftypM4V *M4V M4A mp42isom*a┌moovlmvhd...
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Publication date: September 2017 Source: Free Radical Biology and Medicine, Volume 110 Author(s): Lucía Fernández-del-Río, Anish Nag, Elen...
