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1.
J Geriatr Oncol ; 13(1): 74-81, 2022 01.
Article in English | MEDLINE | ID: mdl-34446378

ABSTRACT

BACKGROUND: Health related quality of life (HRQL) is an important outcome measure in geriatric oncology. Surgery is the main treatment for colorectal cancer (CRC) but has been associated with a loss of HRQL in older patients. This study aimed to identify determinants for a decreased HRQL at three months after CRC diagnosis. METHOD: This multi-centre observational cohort study (NCT04443816) included 273 patients aged ≥70 years diagnosed with non-metastatic CRC. A multi-domain frailty screening was performed in each patient. A decreased HRQL was defined as a mean difference ≥ 10 on the EORTC QLQ-C30 questionnaire between baseline and three months after CRC diagnosis. Determinants of a decreased HRQL were analysed using multivariable logistic regression. RESULTS: A decrease in HRQL occurred in 63 patients (23.1%). Non-surgical patients had the highest risk of decreased HRQL three months after diagnosis (adjusted odds ratio (OR) 6.4 (95% confidence interval (CI) 2.0-19.8)). The Charlson Comorbidity Index (CCI) (aOR 2.3 (95% (CI) 1.2-4.2)), the American Association of Anesthesiologists class (aOR 2.6 (95%CI 1.4-4.9)), impaired daily functioning (aOR 2.7 (95%CI 1.3-5.6)) and dependent living (aOR 1.9 (95%CI 1.1-4.5)) were associated with a decreased HRQL, mainly caused by non-surgical patients. In surgical patients, a major postoperative complication was a strong determinant of decreased HRQL and was associated with preoperative comorbidity and cognitive impairment (aOR 4.0 (95%CI 1.9-8.8)). CONCLUSION: Frailty characteristics are highly prevalent in older patients at time of CRC diagnosis but not strongly associated with a decreased HRQL after three months. Non-surgical patients and patients with major postoperative complications had the highest risk of decreased HRQL. Registered at clinicaltrials.gov trial number: NCT04443816.


Subject(s)
Colorectal Neoplasms , Frailty , Aged , Cohort Studies , Colorectal Neoplasms/surgery , Frailty/diagnosis , Frailty/epidemiology , Humans , Quality of Life , Surveys and Questionnaires
2.
Photochem Photobiol Sci ; 12(4): 690-5, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23128085

ABSTRACT

We present a novel manufacture route for silica-titania photocatalysts using the diatom microalga Pinnularia sp. Diatoms self-assemble into porous silica cell walls, called frustules, with periodic micro-, meso- and macroscale features. This unique hierarchical porous structure of the diatom frustule is used as a biotemplate to incorporate titania by a sol-gel methodology. Important material characteristics of the modified diatom frustules under study are morphology, crystallinity, surface area, pore size and optical properties. The produced biosilica-titania material is evaluated towards photocatalytic activity for NOx abatement under UV radiation. This research is the first step to obtain sustainable, well-immobilised silica-titania photocatalysts using diatoms.


Subject(s)
Silicon Dioxide/chemistry , Titanium/chemistry , Ultraviolet Rays , Air Pollution/prevention & control , Catalysis , Diatoms/chemistry , Diatoms/radiation effects , Diatoms/ultrastructure , Hydrolysis , Nitrogen Oxides/chemistry , Porosity
3.
Chemphyschem ; 13(18): 4251-7, 2012 Dec 21.
Article in English | MEDLINE | ID: mdl-23150192

ABSTRACT

Photocatalytic soot oxidation is studied on P25 TiO(2) as an important model reaction for self-cleaning processes by means of electron paramagnetic resonance (EPR) and Fourier transform infrared (FTIR) spectroscopy. Contacting of carbon black with P25 leads on the one hand to a reduction of the local dioxygen concentration in the powder. On the other hand, the weakly adsorbed radicals on the carbon particles are likely to act as alternative traps for the photogenerated conduction-band electrons. We find furthermore that the presence of dioxygen and oxygen-related radicals is vital for the photocatalytic soot degradation. The complete oxidation of soot to CO(2) is evidenced by in situ FTIR spectroscopy, no intermediate CO is detected during the photocatalytic process.


Subject(s)
Soot/chemistry , Carbon/chemistry , Carbon Dioxide/chemistry , Carbon Monoxide/chemistry , Catalysis , Electron Spin Resonance Spectroscopy/methods , Electrons , Oxidation-Reduction , Oxygen/chemistry , Photochemical Processes , Spectroscopy, Fourier Transform Infrared/methods
4.
PLoS One ; 7(3): e32825, 2012.
Article in English | MEDLINE | ID: mdl-22442670

ABSTRACT

Small stationary diesel engines, like in generator sets, have limited emission control measures and are therefore responsible for 44% of the particulate matter (PM) emissions in the United States. The diesel exhaust composition depends on operating conditions of the combustion engine. Furthermore, the measurements are influenced by the used sampling method. This study examines the effect of engine loading and exhaust gas dilution on the composition of small-scale power generators. These generators are used in different operating conditions than road-transport vehicles, resulting in different emission characteristics. Experimental data were obtained for gaseous volatile organic compounds (VOC) and PM mass concentration, elemental composition and nitrate content. The exhaust composition depends on load condition because of its effect on fuel consumption, engine wear and combustion temperature. Higher load conditions result in lower PM concentration and sharper edged particles with larger aerodynamic diameters. A positive correlation with load condition was found for K, Ca, Sr, Mn, Cu, Zn and Pb adsorbed on PM, elements that originate from lubricating oil or engine corrosion. The nitrate concentration decreases at higher load conditions, due to enhanced nitrate dissociation to gaseous NO at higher engine temperatures. Dilution on the other hand decreases PM and nitrate concentration and increases gaseous VOC and adsorbed metal content. In conclusion, these data show that operating and sampling conditions have a major effect on the exhaust gas composition of small-scale diesel generators. Therefore, care must be taken when designing new experiments or comparing literature results.


Subject(s)
Electricity , Metals/analysis , Nitrates/analysis , Vehicle Emissions/analysis , Volatile Organic Compounds/analysis
5.
J Lab Autom ; 17(2): 134-43, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22357557

ABSTRACT

Photocatalytic activity can be studied by several methods, each with its own strengths and weaknesses. To study photocatalytic activity in an easy, user-friendly, and realistic way, a completely new setup has been built. The setup is modularly constructed around Fourier transform infrared spectroscopy (FTIR) spectroscopy at the heart of it, resulting in great versatility. Complementary software has been written for automatic control of the setup and for processing the generated data. Two pollutants, oil and n-octane, are tested to validate the performance of the setup. These validation experiments confirm the usefulness and added value of the setup in general and of the FTIR detection methodology as well. It becomes clear that a system of online measurements with good repeatability, accuracy, and user-friendliness has been created.


Subject(s)
Automation, Laboratory/methods , Catalysis , Photolysis , Spectroscopy, Fourier Transform Infrared/methods , Environmental Pollutants/metabolism , Octanes/metabolism , Oils/metabolism , Software
6.
Appl Microbiol Biotechnol ; 89(2): 303-14, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20878323

ABSTRACT

In this study, the microbial community characteristics in continuous lab-scale anaerobic reactors were correlated to reactor functionality using the microbial resource management (MRM) approach. Two molecular techniques, denaturing gradient gel electrophoresis (DGGE) and terminal-restriction fragment length polymorphism (T-RFLP), were applied to analyze the bacterial and archaeal communities, and the results obtained have been compared. Clustering analyses showed a similar discrimination of samples with DGGE and T-RFLP data, with a clear separation between the meso- and thermophilic communities. Both techniques indicate that bacterial and mesophilic communities were richer and more even than archaeal and thermophilic communities, respectively. Remarkably, the community composition was highly dynamic for both Bacteria and Archaea, with a rate of change between 30% and 75% per 18 days, also in stable performing periods. A hypothesis to explain the latter in the context of the converging metabolism in anaerobic processes is proposed. Finally, a more even and diverse bacterial community was found to be statistically representative for a well-functioning reactor as evidenced by a low Ripley index and high biogas production.


Subject(s)
Archaea/genetics , Archaea/metabolism , Bacteria/genetics , Bacteria/metabolism , Bioreactors/microbiology , Anaerobiosis , Archaea/chemistry , Archaea/isolation & purification , Bacteria/chemistry , Bacteria/isolation & purification , Denaturing Gradient Gel Electrophoresis , Polymorphism, Restriction Fragment Length
7.
Bioresour Technol ; 102(2): 592-9, 2011 Jan.
Article in English | MEDLINE | ID: mdl-20813520

ABSTRACT

Five different pre-treatments were investigated to enhance the solubilisation and anaerobic biodegradability of kitchen waste (KW) in thermophilic batch and continuous tests. In the batch solubilisation tests, the highest and the lowest solubilisation efficiency were achieved with the thermo-acid and the pressure-depressure pre-treatments, respectively. However, in the batch biodegradability tests, the highest cumulative biogas production was obtained with the pressure-depressure method. In the continuous tests, the best performance in terms of an acceptable biogas production efficiency of 60% and stable in-reactor CODs and VFA concentrations corresponded to the pressure-depressure reactor, followed by freeze-thaw, acid, thermo-acid, thermo and control. The maximum OLR (5 g COD L(-1) d(-1)) applied in the pressure-depressure and freeze-thaw reactors almost doubled the control reactor. From the overall analysis, the freeze-thaw pre-treatment was the most profitable process with a net potential profit of around 11.5 € ton(-1) KW.


Subject(s)
Methane/metabolism , Refuse Disposal/methods , Sewage/analysis , Anaerobiosis , Biodegradation, Environmental , Biofuels , Bioreactors/microbiology , Cost-Benefit Analysis , Hydrolysis , Kinetics , Refuse Disposal/economics , Solubility , Time Factors
8.
Gastrointest Endosc ; 71(1): 64-70, 70.e1, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19906368

ABSTRACT

BACKGROUND: EUS-guided FNA is currently advocated in lung cancer staging guidelines as an alternative for surgical staging to prove mediastinal metastases. To date, training requirements for chest physicians to obtain competency in EUS for lung cancer staging are unknown. OBJECTIVE: To test a training and implementation strategy for EUS for the diagnosis and staging of lung cancer. DESIGN: Prospective national multicenter implementation trial. Nine (chest) physicians from 5 hospitals participated in a dedicated EUS educational program (investigation of 50 patients) for the diagnosis and staging of lung cancer. EUS outcomes of trainees were compared with those of the training center. SETTING: Four general hospitals, the national cancer center (implementation centers), and a tertiary referral center (expert center). PATIENTS: This study involved 551 consecutive patients with (suspected) lung cancer, all candidates for surgical staging, who underwent EUS in 1 of the 5 implementation centers (n = 346) or the single expert center (n = 205). Surgical-pathological staging was the reference standard in case no mediastinal metastases were found. RESULTS: EUS had a sensitivity of 83% versus 82% and accuracy of 89% versus 88% for mediastinal nodal staging (implementation center vs expert center). Surgery was spared because of EUS findings in 51% versus 54% of patients. A single complication occurred in each group. LIMITATION: Surgical-pathological verification of mediastinal nodes was not available in all patients staged negative at EUS. CONCLUSION: Chest physicians who participate in a dedicated training and implementation program for EUS in lung cancer staging can obtain results similar to those of experts for mediastinal nodal staging.


Subject(s)
Carcinoma, Non-Small-Cell Lung/diagnostic imaging , Endosonography/methods , Lung Neoplasms/diagnostic imaging , Neoplasm Staging/methods , Aged , Biopsy, Fine-Needle , Carcinoma, Non-Small-Cell Lung/pathology , Female , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Prospective Studies
9.
Clin Cancer Res ; 14(19): 6259-63, 2008 Oct 01.
Article in English | MEDLINE | ID: mdl-18829506

ABSTRACT

PURPOSE: Surgical resection as part of a multimodality approach in malignant pleural mesothelioma (MPM) has a high morbidity and mortality. Because mediastinal lymph node (MLN) metastases are a negative prognostic factor, preoperative staging is of paramount importance. Transesophageal endoscopic ultrasound with real-time guided fine needle aspiration (EUS-FNA) enables accurate MLN staging in lung cancer. EXPERIMENTAL DESIGN: The feasibility and yield of EUS-FNA in MLN staging were prospectively analyzed in patients with presumed early-stage MPM considered for multimodality therapy. MLN reference pathology was defined by either pathologic staging or the formal demonstration of malignant cells by either EUS-FNA or mediastinoscopy. RESULTS: Thirty-two consecutive patients (81% males; median age, 61 years) with proven MPM underwent EUS-FNA. In 11 (34%) patients, a negative EUS-FNA or mediastinoscopy was not confirmed by surgical MLN dissection because of clinical deterioration or disease progression. In 21 (66%) patients, a formal pathology of the MLN was obtained and staging with EUS-FNA was positive in 4 (19%). Mediastinoscopy did not result in a greater yield of MLN metastasis as compared with EUS-FNA. Thoracotomy with complete lymph node dissection was done in 17 (81%). The overall prevalence of MLN metastasis was 24%, and the sensitivity of EUS-FNA was 80% (95% confidence interval, 28-99%) with a specificity of 100% (95% confidence interval, 79-100%). One patient had esophageal perforation related to EUS-FNA. CONCLUSIONS: EUS-FNA is feasible and sensitive for MLN staging in patients with MPM who are candidate for multimodality treatment. These data warrant further evaluation.


Subject(s)
Endosonography/methods , Esophagus/diagnostic imaging , Esophagus/pathology , Mesothelioma/diagnostic imaging , Mesothelioma/diagnosis , Neoplasm Staging/instrumentation , Pleural Neoplasms/diagnostic imaging , Pleural Neoplasms/diagnosis , Adult , Aged , Biopsy, Fine-Needle , Disease Progression , Female , Humans , Lymphatic Metastasis/pathology , Male , Mesothelioma/pathology , Middle Aged , Neoplasm Staging/methods , Pleural Neoplasms/pathology , Prognosis , Sensitivity and Specificity
10.
Biomark Med ; 2(3): 253-89, 2008 Jun.
Article in English | MEDLINE | ID: mdl-20477414

ABSTRACT

Colorectal cancer (CRC) is the third most common cancer worldwide. Successful treatment is heavily dependent on tumor stage at the time of detection, but unfortunately CRC is often only detected in advanced stages. New biomarkers in the form of genes or proteins that can be used for diagnosis, prognostication, follow-up, and treatment selection and monitoring could be of great benefit for the management of CRC. Furthermore, proteins could prove valuable new targets for therapy. Therefore, clinical proteomics has gained a lot of scientific interest in this regard. To get an overall insight into the extent to which this research has contributed to a better management of CRC, we give a comprehensive overview of the results of proteomics research on CRC, focusing on expression proteomics, in other words, protein profiling studies. Furthermore, we evaluate the potential of the discriminating proteins identified in this research for clinical use as biomarkers for (early) diagnosis, prognosis and follow-up of CRC or as targets for new therapeutic regimens.

12.
Biomark Insights ; 3: 375-385, 2008 Jul 02.
Article in English | MEDLINE | ID: mdl-19578519

ABSTRACT

Colorectal cancer (CRC) is the second most common cause of cancer-related death in Europe and its prognosis is largely dependent on stage at diagnosis. Currently, there are no suitable tumour markers for early detection of CRC. In a retrospective study we previously found discriminative CRC serum protein profiles with surface enhanced laser desorption ionisation-time of flight mass spectrometry (SELDI-TOF MS). We now aimed at prospective validation of these profiles. Additionally, we assessed their applicability for follow-up after surgery and investigated tissue protein profiles of patients with CRC and adenomatous polyps (AP). Serum and tissue samples were collected from patients without known malignancy with an indication for colonoscopy and patients with AP and CRC during colonoscopy. Serum samples of controls (CON; n = 359), patients with AP (n = 177) and CRC (n = 73), as well as tissue samples from AP (n = 52) and CRC (n = 47) were analysed as described previously. Peak intensities were compared by non-parametric testing. Discriminative power of differentially expressed proteins was assessed with support vector machines (SVM). We confirmed the decreased serum levels of apolipoprotein C-1 in CRC in the current population. No differences were observed between CON and AP. Apolipoprotein C-I levels did not change significantly within 1 month post-surgery, although a gradual return to normal levels was observed. Several proteins differed between AP and CRC tissue, among which a peak with similar mass as apolipoprotein C-1. This peak was increased in CRC compared to AP. Although we prospectively validated the serum decrease of apolipoprotein C-1 in CRC, serum protein profiles did not yield SVM classifiers with suitable sensitivity and specificity for classification of our patient groups.

13.
Gastrointest Endosc ; 61(6): 671-8, 2005 May.
Article in English | MEDLINE | ID: mdl-15855970

ABSTRACT

BACKGROUND: Light-induced fluorescence endoscopy (LIFE) may improve the detection of high-grade dysplasia (HGD) and early stage cancer (EC) in Barrett's esophagus (BE). The aim of this study was to compare LIFE with standard endoscopy (SE) in a randomized crossover study. METHODS: Fifty patients with BE underwent SE and LIFE in a randomized sequence (4 to 6-week interval between procedures). The two procedures were performed by two different endoscopists who were blinded to the findings of the other examination. Targeted biopsy specimens were taken from detected lesions, followed by random biopsy specimens with a 2-cm interval, 4-quadrant protocol. Biopsy specimens were routinely evaluated and subsequently reviewed by a single, blinded expert GI pathologist. RESULTS: Targeted biopsy specimens had a sensitivity for the diagnosis of HGD/EC of 62% (8/13) for both techniques. The overall sensitivity (all biopsy specimens) was 85% for SE and 69% for LIFE (p = 0.69). All targeted biopsy specimens had a positive predictive value (PPV) for HGD/EC of 41% for SE and 28% for LIFE (p = 0.40); autofluorescence-targeted biopsy specimens had a PPV of 13%. False-positive lesions had a significantly higher rate of acute inflammation than random biopsy specimens. CONCLUSIONS: In this study, LIFE did not improve the detection of HGD or EC in patients with BE compared with SE.


Subject(s)
Barrett Esophagus/pathology , Carcinoma/pathology , Esophageal Neoplasms/pathology , Esophagoscopy/methods , Fluorescence , Precancerous Conditions/pathology , Video Recording , Biopsy , Cross-Over Studies , False Positive Reactions , Female , Follow-Up Studies , Humans , Male , Middle Aged , Prospective Studies , Reproducibility of Results , Sensitivity and Specificity
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